CN120357043A

CN120357043A - Battery cell, packaging method thereof, packaging system, solid-state battery and hot-melt resin material

Info

Publication number: CN120357043A
Application number: CN202510833226.8A
Authority: CN
Inventors: 汪齐; 牟丽莎; 范天驰; 杜长虹; 吴振豪
Original assignee: Chongqing Changan Automobile Co Ltd
Current assignee: Chongqing Changan Automobile Co Ltd
Priority date: 2025-06-20
Filing date: 2025-06-20
Publication date: 2025-07-22

Abstract

The application relates to the technical field of solid-state batteries and discloses an electric core, which comprises a lamination structure and a packaging structure, wherein the lamination structure comprises a negative pole piece and a positive pole piece which are alternately overlapped, a solid electrolyte layer is arranged between the adjacent positive pole piece and the negative pole piece, a sheet layer gap is formed on the peripheral side of the lamination structure, the packaging structure comprises a filling part and a penetrating part, the filling part is arranged in the sheet layer gap, and the penetrating part extends from the filling part to penetrate into the sheet layer. The arrangement of the penetrating part ensures the interface combination effect of the packaging structure and the sheet layer of the lamination structure, improves the combination strength, and the active material area of the penetrating part penetrating the electrode sheet improves cohesive force and has certain deformation capacity so as to adapt to the forming pressure of the lamination battery core and the volume change of the active material, and avoid the generation of new edge stress caused by the separation contact and overlarge deformation of the packaging structure and the sheet layer, thereby improving the performance of the solid-state battery. The application also discloses a packaging method, a packaging system, a solid-state battery and a hot-melt type resin material.

Description

Battery cell, packaging method thereof, packaging system, solid-state battery and hot-melt resin material

Technical Field

The application relates to the technical field of solid-state batteries, in particular to a battery cell, a packaging method and a packaging system thereof, a solid-state battery and a hot-melt resin material.

Background

Extremely high energy density, high multiplying power, high safety, long service life, wide temperature range and low cost are targets that power batteries are always pursued, and along with the rapid development of new energy automobiles, traditional lithium ion batteries using liquid electrolytes are gradually unable to meet the requirements of the market on battery performance, and development of next-generation battery technologies is urgently needed. The solid electrolyte used in the solid battery has higher mechanical strength, and the electrolyte consumption and interface side reaction are far less than those of the liquid battery, so that the solid electrolyte has remarkable advantages in the aspects of energy density, safety, service life, climate adaptability and the like. Because of solid-solid contact among the components, the interface impedance is large, and the solid-state battery needs to be pressurized and densified during manufacturing. Conventional winding processes are difficult to accommodate with huge forming pressures, and lamination processes based on rolling or isostatic pressing are currently the first choice for solid state batteries.

In the solid-state battery lamination process, positive and negative pole pieces with equal size can be subjected to pole piece dislocation under the influence of insufficient precision of lamination equipment, and the pole piece dislocation easily causes the risk of short circuit caused by lithium precipitation at the edge of a negative electrode in the charging and discharging process of the battery. To solve this problem, the area of the negative electrode sheet is generally designed to be slightly larger than the area of the positive electrode sheet so that the negative electrode can completely cover the positive electrode (i.e., overhang design). However, because the positive and negative electrode plates are unequal, when larger forming pressure (such as isostatic pressure or rolling pressure) is applied, residual partial stress concentration at the edge of the electrode plates is easy to induce, the edge of the electrolyte membrane is broken under the action of shearing force, so that the edge contact of the positive and negative electrode plates is caused to generate internal short circuit, the manufacturing yield of the battery is reduced, and the yield is more remarkable particularly when a multi-laminated solid-state battery cell is manufactured. For the lamination of solid-state batteries overhang and the isostatic process yield problem, a corresponding study has been carried out on the short-circuit prevention solid-state batteries by a person skilled in the art.

At present, aiming at the problem that the anode and cathode contact and further cause battery short circuit in the solid-state battery assembly process of the anode overhang area, filling substances in gaps corresponding to the anode overhang area are mostly adopted for packaging and supporting so as to avoid the collapse of the anode overhang area in the solid-state battery assembly process, but in the actual research and development process, the fact that the existing packaging and supporting structure of the overhang area is subjected to stress deformation and size shrinkage in the lamination cell isostatic pressing process is found, so that the deformation/shrinkage amplitude of the pole piece and the packaging and supporting structure is inconsistent, the packaging and supporting structure is partially debonded, even the whole piece is separated from the edge of the pole piece, the yield of a cell cannot be effectively improved, and the performance of a subsequent battery is even affected.

It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the application and thus may include information that does not form the prior art that is already known to those of ordinary skill in the art.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview, and is intended to neither identify key/critical elements nor delineate the scope of such embodiments, but is intended as a prelude to the more detailed description that follows.

The embodiment of the disclosure provides a battery cell, a packaging method and a packaging system thereof, a solid-state battery and a hot-melt resin material, so as to solve the problems that a sheet layer gap packaging structure of the traditional laminated battery cell is easy to debond, even the whole sheet is easy to fall off from the edge of a pole piece, and the yield and the subsequent performance of the battery are influenced.

In some embodiments, the battery cell comprises a lamination structure, wherein the lamination structure comprises a negative electrode plate and a positive electrode plate which are alternately overlapped, a solid electrolyte layer is arranged between the adjacent positive electrode plate and the negative electrode plate, a peripheral side surface of the lamination structure forms a sheet gap, a packaging structure comprises a filling part and a penetrating part, the filling part is arranged in the sheet gap of the lamination structure, the penetrating part is a part which extends from the filling part to the inside of a sheet around the sheet gap, and the penetrating depth of the penetrating part is greater than or equal to 1 mu m.

In some embodiments, the packaging method of the battery cell comprises the steps of stacking a positive electrode plate, a negative electrode plate and a solid electrolyte layer in sequence to obtain a laminated structure, wherein a sheet gap is formed on the peripheral side surface of the laminated structure, packaging materials are arranged in the sheet gap of the laminated structure to obtain the battery cell with the packaging structure, and the packaging materials can permeate into the inside of the sheet layer around the sheet gap to form a permeation part.

In some embodiments, the solid-state battery comprises the battery cell, or the battery cell obtained by the battery cell packaging method.

In some embodiments, the packaging system of the battery cell comprises a fluid material precise coating device, a transmitting and positioning module, a scanning module, a control unit, a slicing processing and coating parameter design of the contour three-dimensional model, wherein the transmitting and positioning module is used for overturning a lamination structure of a finished lamination to the vertical direction and then transmitting the lamination structure to a working area of the fluid material precise coating device, the scanning module is used for scanning contour entity data of a side surface to be printed of the lamination structure arranged in the working area of the fluid material precise coating device, the control unit is used for obtaining the contour three-dimensional model according to the contour entity data, the slicing processing is carried out on the contour three-dimensional model, the coating information is obtained, and the fluid material precise coating device receives the coating information of the control unit and is used for arranging the melted packaging material heated to a preset temperature on the side surface to be printed of the lamination structure arranged in the working area according to the coating information.

In some embodiments, the hot-melt resin material is used as an encapsulating material of the encapsulating structure of the battery cell, or used as an encapsulating material in the encapsulating method of the battery cell, or used as an encapsulating material of a 3D printing device of the encapsulating system of the battery cell, and comprises, by mass, 40-80 parts of a matrix resin, 5-10 parts of a compatibilizer, 0-3 parts of a coupling agent and 0-60 parts of an inorganic filler, wherein the matrix resin comprises a polymer containing one or more polar functional groups of an ester group, a carboxyl group, an anhydride group, an amide group, an amino group, a hydroxyl group and an epoxy group.

In some embodiments, the solid-state battery comprises the battery cell, the battery cell obtained by packaging the battery cell by the packaging method of the battery cell, or the battery cell obtained by packaging the battery cell by the packaging system of the battery cell.

The battery cell, the packaging method, the packaging system, the solid-state battery and the hot melt type resin material provided by the embodiment of the disclosure can realize the following technical effects:

In the battery cell of the embodiment of the disclosure, the packaging structure comprises the filling part arranged in the sheet gap of the lamination structure, and the penetration part penetrating into the sheet layer around the sheet gap, and the arrangement of the penetration part ensures the interface bonding effect of the packaging structure and the sheet layer of the lamination structure, improves the bonding strength of the packaging structure and the sheet layer, and the penetration part penetrates into the active material region of the electrode sheet to improve cohesive force and have certain deformability so as to adapt to the forming pressure of the lamination battery cell and the volume change of the active material (including the forming pressure and the volume change caused by charging and discharging), thereby avoiding the separation contact of the packaging structure and the sheet layer (electrode sheet and/or solid electrolyte layer), and particularly solving the problem that the separation contact of the packaging structure and the sheet layer is caused by overlarge sheet layer deformation in the isostatic pressing forming process of the solid-state battery to form new edge stress. That is, the battery cell of the embodiment of the disclosure breaks through the technical limitation of the existing sheet gap packaging structure, the packaging material permeates into the electrode material region through design, although the theoretical calculation has small energy loss (generally controlled within 1%), the bonding strength of the packaging structure and the lamination structure is improved, detachment cannot occur, particularly detachment cannot occur after the isostatic compaction process of the solid-state battery, the battery yield is improved, and meanwhile, the utilization rate of the electrode active material and the performance of the solid-state battery can be improved.

The battery cell packaging method disclosed by the embodiment of the disclosure has more practicability, can use continuous coating pole pieces, is compatible with overhang designs and sizes of positive pole pieces and negative pole pieces and the like, can simplify the edge short-circuit prevention treatment of a single pole piece into the edge short-circuit prevention packaging of a lamination structure, and greatly reduces the manufacturing process difficulty, period and cost of the battery.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which like reference numerals refer to similar elements, and in which:

Fig. 1 is a schematic structural diagram of a battery cell according to an embodiment of the present disclosure;

FIG. 2 is a schematic view of a partially enlarged structure of another cell provided by an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of another battery cell provided in an embodiment of the present disclosure;

Fig. 4 is a schematic structural diagram of another battery cell provided in an embodiment of the present disclosure;

Fig. 5 is a flow chart of a method for packaging a battery cell according to an embodiment of the disclosure;

fig. 6 is a flowchart of another method for packaging a battery cell according to an embodiment of the disclosure;

FIG. 7 is a schematic view of a heat press apparatus according to an embodiment of the present disclosure;

fig. 8 is a schematic structural diagram of a battery cell packaging system according to an embodiment of the disclosure;

fig. 9a is a cross-sectional scanning electron micrograph of a cell of example 1 of the present disclosure;

FIG. 9b is an EDS elemental analysis photograph of a cross-section of a cell of example 1 of the present disclosure;

fig. 10a is a cross-sectional scanning electron micrograph of a cell of comparative example 5 of the present disclosure;

FIG. 10b is a photograph of an EDS elemental analysis of a cross-section of a cell of comparative example 5 of the present disclosure;

fig. 11a and 11b are schematic diagrams showing the package structure of the battery cell of comparative example 5 of the present disclosure in a deformed or detached state;

Fig. 12 is a charge-discharge graph of the battery cells of example 1 and comparative example 1 of the present disclosure;

fig. 13 is a graph of the cycling performance of the un-shorted cells of example 1 and comparative example 1 of the present disclosure.

Reference numerals:

10. Lamination structure, 11, negative pole piece, 111, negative pole active material layer, 112, negative pole current collector layer, 1121, burr, 1122, pole piece edge defect, 12, solid electrolyte layer, 13, positive pole piece, 131, positive pole active material layer, 132, positive current collector layer, 1301, dislocation bulge, 1302, dislocation dent, 20, packaging structure, 21, filling part, 210, penetrating part, 22, cladding part;

30. 31 parts of hot press device, 310 parts of heating plate, 311 parts of heating groove, 32 parts of vibration structure and 32 parts of pressing plate;

41. fluid material precise coating equipment 42, a scanning module 43 and a control unit.

Detailed Description

So that the manner in which the features and techniques of the disclosed embodiments can be understood in more detail, a more particular description of the embodiments of the disclosure, briefly summarized below, may be had by reference to the appended drawings, which are not intended to be limiting of the embodiments of the disclosure. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may still be practiced without these details. In other instances, well-known structures and devices may be shown simplified in order to simplify the drawing.

The terms first, second and the like in the description and in the claims of the embodiments of the disclosure and in the above-described figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the disclosure described herein are, for example, capable of understanding the embodiments of the disclosure described herein. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion.

In the embodiments of the present disclosure, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are used primarily to better describe embodiments of the present disclosure and embodiments thereof and are not intended to limit the indicated device, element, or component to a particular orientation or to be constructed and operated in a particular orientation. Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in the embodiments of the present disclosure will be understood by those of ordinary skill in the art in view of the specific circumstances.

In addition, the terms "disposed," "connected," "secured" and "affixed" are to be construed broadly. For example, the term "coupled" may be a fixed connection, a removable connection, or a unitary construction, may be a mechanical connection, or an electrical connection, may be a direct connection, or may be an indirect connection via an intermediary, or may be an internal communication between two devices, elements, or components. The specific meaning of the above terms in the embodiments of the present disclosure may be understood by those of ordinary skill in the art according to specific circumstances.

The term "plurality" means two or more, unless otherwise indicated.

In the embodiment of the present disclosure, the character "/" indicates that the front and rear objects are an or relationship. For example, A/B represents A or B.

The term "and/or" is an associative relationship that describes an object, meaning that there may be three relationships. For example, A and/or B, represent A or B, or three relationships of A and B.

It should be noted that, without conflict, the embodiments of the present disclosure and features of the embodiments may be combined with each other.

As shown in fig. 1 to 4, the embodiment of the present disclosure provides a battery cell, which includes a lamination structure 10 and a packaging structure 20, wherein the lamination structure 10 includes a negative electrode tab 11 and a positive electrode tab 13 that are alternately stacked, a solid electrolyte layer 12 is disposed between adjacent positive electrode tab 13 and negative electrode tab 11, and a peripheral side of the lamination structure 10 forms a sheet gap. The package structure 20 includes a filling portion 21 and a penetration portion 210, the filling portion 21 is disposed in a sheet gap of the lamination structure 10, the penetration portion 210 is a portion extending from the filling portion 21 to penetrate into a sheet inside of a periphery of the sheet gap, and a penetration depth of the penetration portion 210 is greater than or equal to 1 μm.

In the battery core of the embodiment of the disclosure, the packaging structure includes, besides the filling portion 21 disposed in the sheet gap of the lamination structure 10, a penetration portion 210 penetrating into the sheet layer around the sheet gap, where the penetration portion 210 is disposed to ensure the interface bonding effect between the packaging structure 20 and the sheet layer of the lamination structure 10, improve the bonding strength between the packaging structure and the sheet layer, and the active material region of the penetration portion penetrates into the electrode sheet to promote cohesive force and have a certain deformation capability, so as to adapt to the molding pressure of the lamination battery core and the volume change of the active material (including the volume change caused by the molding pressure and charge and discharge), and avoid the new edge stress generated due to the separation contact and the overlarge deformation of the packaging structure and the sheet layer (the electrode sheet and/or the solid electrolyte layer), thereby improving the performance of the solid-state battery.

In the battery cell of the embodiment of the disclosure, the bonding strength of the packaging structure and the sheet layer of the lamination structure reaches 1.2MPa or more. The first-cycle discharge specific capacity of the solid-state battery obtained by the battery cell assembly of the embodiment of the disclosure can be improved.

In the battery cell of the embodiment of the present disclosure, "inside the sheet layer" refers to inside the positive electrode sheet, the negative electrode sheet, and the solid electrolyte layer, more specifically, the positive electrode active material layer, the negative electrode active material layer, and the solid electrolyte layer.

In the battery cell of the embodiment of the present disclosure, the filling rate of the package structure 20 to the sheet layer gap is greater than or equal to 60%. Optionally, the filling rate is greater than or equal to 70%. Optionally, the filling rate is greater than or equal to 80%. Optionally, the filling rate is greater than or equal to 90%.

The battery cell of the embodiment of the disclosure is a laminated battery cell and can be used as a battery cell of a solid-state battery. Alternatively, lamination stack 10 includes one or more lamination units, each lamination unit including one negative electrode sheet 11, one solid electrolyte layer 12, and one positive electrode sheet 13 stacked in sequence. When the lamination stack 10 includes a plurality of lamination units, the positive electrode tab 13 of one lamination unit is stacked with the negative electrode tab of an adjacent lamination unit through the solid electrolyte layer. That is, the lamination stack 10 is arranged and stacked in such a manner that the anode electrode sheet 11/solid electrolyte layer 12/cathode electrode sheet 13/solid electrolyte layer 12/anode electrode sheet 11/solid electrolyte layer 12/cathode electrode sheet 13/. In general, electrode tabs on both surfaces of the lamination stack 10 are negative electrode tabs 11, which is of course not limited thereto.

In the battery cell of the embodiment of the disclosure, the sheet layer comprises a pole piece (a positive pole piece and a negative pole piece) and a solid electrolyte layer, and the sheet layer gap is a gap formed between the pole pieces or between the pole pieces and the solid electrolyte layer. The gaps of the sheet layers are different according to the size design of the pole pieces. Optionally, the sheet voids include dislocation voids and/or overhang voids, where the anode electrode sheet, the solid electrolyte layer, and the cathode electrode sheet are caused to be misaligned when stacked, and typically, the equally sized cathode electrode sheet and the anode electrode sheet are not aligned when stacked (see fig. 3). The equi-sized design generally refers to the equal area of the active material region. The overhang void is an overhang void (i.e., overhang void) corresponding to a overhang region formed by the negative electrode tab beyond at least one side of the negative electrode tab in the circumferential direction, in which case the negative electrode tab is designed to be larger than the positive electrode tab such that at least one side of the negative electrode tab in the circumferential direction exceeds a overhang region formed by the positive electrode tab (see fig. 1 and 4). The dislocation space and/or the overhang space extend inward of the lamination structure 10 with respect to the outer contour of the periphery of the lamination structure 10, have a certain depth (see depth shown as d1 in fig. 2), and easily cause a problem of short circuit of the battery cells due to concentration of stress under molding pressure when assembling the solid-state battery, thereby reducing the manufacturing yield and performance uniformity of the battery cells. The package structure 20 fills the dislocation gaps and/or the overhang gaps, so that the problem that the cell short circuit is easily caused by stress concentration of the sheet gaps under forming pressure can be solved, meanwhile, the package structure also has a penetration part 210 penetrated into the sheet layers around the sheet gaps, the arrangement of the penetration part 210 ensures the interface bonding effect of the package structure 20 and the sheet layers of the lamination structure 10, and the bonding strength of the package structure and the sheet layers is improved.

In the battery cell of the embodiment of the disclosure, the penetrating portion 210 of the packaging structure 20 penetrates into the sheet layer around the sheet layer gap of the lamination structure 10, for example, the penetrating portion 210 penetrates into the active material of the positive electrode sheet around the sheet layer gap and the active material of the solid electrolyte layer and the negative electrode sheet (see fig. 2), so that, in theory, the packaging material penetrating into the sheet layer can cause the positive electrode sheet 13 to lose part of the theoretical capacity, however, in practical application, the setting of the penetrating portion 210 can not only improve the bonding strength of the packaging structure and the lamination structure, improve the yield of the battery cell, but also greatly improve the practical playing capacity of the battery cell capacity, and improve the first-ring specific capacity and the cycle performance of the battery, thereby improving the battery performance.

In some embodiments, the penetration depth d2 of the penetration portion 210 is greater than or equal to 1 μm. The theoretical capacity loss and the actual capacity improvement are balanced by controlling the penetration depth, so that the battery performance can be improved. Optionally, the penetration depth of the penetration portion is greater than or equal to 1 μm and less than or equal to 300 μm. Optionally, the penetration depth of the penetration portion is greater than or equal to 10 μm and less than or equal to 300 μm. Optionally, the penetration depth of the penetration portion is greater than or equal to 50 μm and less than or equal to 300 μm. Optionally, the penetration depth of the penetration portion is greater than or equal to 100 μm and less than or equal to 300 μm. Optionally, the penetration depth of the penetration portion is greater than or equal to 150 μm and less than or equal to 300 μm. Optionally, the penetration depth of the penetration portion is greater than or equal to 200 μm and less than or equal to 250 μm. By controlling the penetration depth of the penetration part, the theoretical capacity loss is controlled, and the battery performance can be better improved while the bonding strength is ensured to provide the yield of the battery core.

In some embodiments, the penetration portion comprises less than or equal to 1% of the electrode sheet area. That is, the penetration area of the penetration portion occupies 1% or less of the electrode sheet area. In this embodiment, the theoretical capacity loss and the actual capacity improvement are balanced by controlling the penetration percentage of the penetration portion, so that the battery performance can be improved. Optionally, the penetration area of the penetration portion accounts for less than or equal to 0.8% of the electrode sheet area. In this embodiment, the area (or the infiltration area) of the infiltration portion is calculated by taking the infiltration depth of the infiltration portion as one of the multipliers, for example, taking the positive electrode sheet as an example, and the infiltration area of the infiltration portion is the product of the infiltration depth of the infiltration portion and the peripheral length of the positive electrode sheet.

Optionally, the penetration depth d2 of the penetration portion is less than or equal to 300 μm, and the penetration area of the penetration portion accounts for less than or equal to 1% of the electrode sheet area.

The battery cell of the embodiment of the disclosure is more suitable for large-size battery cells. It can be understood that the larger the size of the battery core is, the smaller the ratio of the penetration depth/penetration area of the penetration part relative to the electrode pole piece area is, the smaller the theoretical capacity loss is, however, the bonding strength of the packaging structure and the lamination structure is not affected, the yield of the battery core is improved, the actual capacity of the battery core capacity is greatly improved, the first-circle specific capacity and the cycle performance of the battery are improved, and the battery performance is further improved.

In some embodiments, as shown in fig. 1 and 4, the packaging structure 20 further includes a cladding portion 22, where the cladding portion 22 is connected with the filling portion 21 and wraps around the peripheral side surface of the lamination structure 10. The battery cell peripheral side end face is wrapped, the defects of the electrode plate edge defect, the foil burrs, the defects left in the former working procedure section such as the misaligned lamination and the like are overcome, and the whole-surrounding type outer frame packaging design protects the environment inside the battery cell, can accommodate the volume change in the battery cell operation process and improves the yield and the battery cell safety performance of the battery cell in an omnibearing manner. For example, the coating portion 22 can coat burrs 1121 and pole piece edge defects 1122 on the negative electrode current collector layer 112, as shown in fig. 4, and misalignment protrusions 1301 and misalignment recesses 1302, etc. generated when the lamination is misaligned. The burrs are easy to pierce through electrolyte membranes, so that micro short circuit is generated due to contact of positive and negative electrodes, self discharge of the battery and deterioration of electrochemical performance are caused, and in terms of safety, the local current density at the micro short circuit exceeds 100A/cm ² (far exceeding 1-5A/cm ² of normal charge and discharge), heat can be rapidly accumulated, and thermal runaway of the battery is caused when the local current density is severe.

In the cell of the embodiment of the present disclosure, the package structure 20 is obtained by disposing the package material into the sheet voids. The packaging material used for the packaging structure 20 may be the same material or different materials. For example, in the case where the package structure 20 includes the filling portion 21, the penetrating portion 210, and the covering portion 22, the filling portion 21 and the penetrating portion 210 are made of the same material, and the covering portion 22 is made of different materials. It will be appreciated that the filling portion 21 and the penetrating portion 210 need to be filled into the sheet voids, and that a potting material having a certain permeability needs to be used to ensure that the potting material can enter the sheet voids and penetrate into the sheet. While the wrapping portion 22 wraps the peripheral side surface of the lamination stack 10, a sealing material having no permeability may be used.

Optionally, the packaging material used for the packaging structure 20 is the same material. The packaging process can be completed in one step, and the packaging process is simplified.

In some embodiments, the encapsulation material of the encapsulation structure 20 comprises an insulating material, i.e. a non-conductive material, e.g. the encapsulation material is selected from one or a combination of several of an oxide, a polymer, a thermoplastic polymer and a composite material.

In some embodiments, the encapsulation material of the encapsulation structure 20 includes a resin material whose penetration ability can vary according to temperature. In general, the higher the heating temperature of the resin material, the better its flow properties and the better its permeability. The flow and permeability of the resin material can be adjusted by controlling the heating temperature of the resin material. Alternatively, the encapsulating material includes a resin material whose penetrability is positively correlated with temperature, that is, the higher the temperature (heating temperature), the better the flow property of the resin material, and the higher the penetrability, whereas the lower the temperature (heating temperature), the worse the flow property of the resin material, and the weaker the penetrability.

In some embodiments, the encapsulation material of the encapsulation structure 20 comprises a hot melt resin material.

In some embodiments, the encapsulation material of encapsulation structure 20 includes a polymer that includes one or more polar functional groups of an ester group (-COO-), a carboxyl group (-COOH), an anhydride group (-C (O) OC (O) -), an amide group (-NHCO-), an amino group (-NH ₂), a hydroxyl group (-OH), an epoxy group (-CH (O) CH-), and the like. In this embodiment, the polymer may be an insulating material, a resin material, or the like, and is not limited as long as it has at least one of the above polar functional groups. The polymer containing the specific polar functional group can further improve the permeability of the packaging material, more effectively penetrate into the inside of the sheet layer, contact and permeate with substances (such as active substances, binders and the like of the sheet layer) in the sheet layer, and improve the bonding strength of the packaging structure.

Alternatively, the encapsulation material of the encapsulation structure 20 includes a resin material having a penetration ability of one or more polar functional groups capable of being changed according to temperature, such as an ester group (-COO-), a carboxyl group (-COOH), an acid anhydride group (-C (O) OC (O) -), an amide group (-NHCO-), an amino group (-NH ₂), a hydroxyl group (-OH), and an epoxy group (-CH (O) CH-), etc.

Alternatively, the encapsulation material of the encapsulation structure 20 includes a hot melt resin material containing one or more polar functional groups of an ester group (-COO-), a carboxyl group (-COOH), an acid anhydride group (-C (O) OC (O) -), an amide group (-NHCO-), an amino group (-NH ₂), a hydroxyl group (-OH), an epoxy group (-CH (O) CH-), and the like.

In some embodiments, the encapsulation material of the encapsulation structure 20 includes one or more of ethylene vinyl acetate copolymer (EVA), ethylene ethyl acrylate copolymer (EEA), polyethylene terephthalate (PET), and ethylene acrylic acid copolymer (EAA).

The insulating material, the resin material, the polymer and other packaging materials can be independently used, and when the packaging material is used, the packaging material is heated and melted to form fluid so that the fluid has certain permeability, and the molten packaging material is arranged in a sheet gap and partially penetrates into the sheet layer to be solidified into a packaging structure. The setting mode is not limited, and can be coating, pouring and the like.

The packaging materials such as the insulating material, the resin material, the polymer and the like can also be compounded with other auxiliary additives to form a composite packaging material so as to improve the packaging effect.

In some embodiments, the encapsulating material of the encapsulation structure 20 further includes auxiliary additives including one or more of a compatibilizer, coupling agent, surfactant, and inorganic filler. Wherein, the types of the compatibilizer, the coupling agent, the surfactant and the inorganic filler are not limited, and the following relevant contents can be referred to.

In some embodiments, the encapsulation material further comprises an auxiliary additive, wherein the mass percentage of the auxiliary additive is 20% -60%. The dosage of the auxiliary additive is controlled, and the packaging effect is ensured. Optionally, the mass percentage of the auxiliary additive is 20% -50%. Optionally, the mass percentage of the auxiliary additive is 20% -40%. Optionally, the mass percentage of the auxiliary additive is 20% -30%. When the auxiliary additives are plural, the proportion of each auxiliary additive is not limited.

Alternatively, when the auxiliary additive includes an organic additive such as a compatibilizer, a coupling agent, a surfactant, or the like, the organic additive includes a polymer containing one or more polar functional groups of an ester group, a carboxyl group, an acid anhydride group, an amide group, an amino group, a hydroxyl group, and an epoxy group. The organic additive containing the specific polar functional group can further improve the permeability of the encapsulation material and more effectively penetrate into the interior of the sheet.

For example, compatibilizers include, but are not limited to, maleic anhydride grafted polyolefin (MAH-g-PO/PP/PE), epoxy modified polyolefin, and the like, and coupling agents include, but are not limited to, gamma-aminopropyl triethoxysilane, and the like.

The embodiment of the disclosure provides a hot melt resin material, which comprises, by mass, 40-80 parts of matrix resin, 5-10 parts of a compatibilizer, 1-3 parts of a coupling agent and 0-60 parts of an inorganic filler. Wherein the matrix resin comprises a polymer comprising one or more polar functional groups of ester groups, carboxyl groups, anhydride groups, amide groups, amino groups, hydroxyl groups, and epoxy groups.

The melting point of the hot melt resin material is 60-100 ℃, the melt index is 200-400 g/10 min, the melt viscosity is 2000-12000 mPa.s, and the contact angle with the surface of the battery pole piece is less than or equal to 60 degrees.

The hot-melt resin material of the embodiment of the disclosure has adjustable fluidity, permeability and mechanical strength after solidification after melting, can be reshaped under the action of temperature and/or vibration, enhances the interaction with active substances, binders and the like in the pole pieces of the lamination structure 10, improves interface contact, and promotes the binding force with the foil and the active substance material region. Meanwhile, the contact angle between the hot melt resin material and the surface of the battery pole piece is less than or equal to 60 degrees, the gap of the pole piece can be rapidly spread and filled, the hot melt resin material can more easily permeate into the inside of the pole piece layer, contact permeation with substances (such as active substances, adhesive and the like of the pole piece) in the pole piece layer is realized, and the bonding strength of the packaging structure is improved.

The hot melt resin material of the embodiments of the present disclosure may be obtained by mixing the components and heating to a melting point to a fluid state when in use, so as to provide fluidity and permeability.

In some embodiments, the matrix resin is selected from one or more of ethylene vinyl acetate copolymer (EVA), ethylene ethyl acrylate copolymer (EEA), polyethylene terephthalate (PET), and ethylene acrylic acid copolymer (EAA). In this embodiment, the type of matrix resin is better for surface contact between the positive and negative electrode active materials and the polymer binder, and is easier to permeate and form stable contact.

Alternatively, the matrix resin is 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts or 80 parts, or any part in the range of 40 to 80 parts by weight.

In some embodiments, the compatibilizer is selected from one or more of maleic anhydride grafted polyolefin (MAH-g-PP/PE), epoxy modified polyolefin, and polypropylene grafted polystyrene (PP-g-PS). In this embodiment, the type of compatibilizer is better for the surface contact of the positive and negative electrode active materials and the polymer binder, and is easier to permeate to form a stable contact.

Optionally, the compatibilizer is 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts, or any part in the range of 5-10 parts by weight.

In some embodiments of the hot melt resin material, the coupling agent comprises a silane coupling agent. Optionally, the silane coupling agent is selected from one or more of gamma-aminopropyl triethoxysilane, vinyl trimethoxysilane and vinyl triethoxysilane. In this example, the silane coupling agent has relatively high chemical stability to the solid electrolyte, and does not cause a significant decrease in ionic conductivity of the electrolyte.

In some embodiments, the hot melt resin material comprises a titanate coupling agent. Alternatively, the titanate coupling agent is selected from isopropyl triisostearate titanate and/or isopropyl dioleate acyloxytitanate. In this example, the titanate coupling agent has relatively high chemical stability to the solid electrolyte, and does not cause a significant decrease in ionic conductivity of the electrolyte.

Optionally, the coupling agent is 1 part, 2 parts or 3 parts, or any part in the range of 1-3 parts by weight.

Optionally, the compatibilizer and/or coupling agent is selected from polymers containing one or more polar functional groups of ester groups, carboxyl groups, anhydride groups, amide groups, amino groups, hydroxyl groups, and epoxy groups. The compatibilizer and/or coupling agent containing the specific polar functional group can further improve the permeability of the packaging material and more effectively penetrate into the interior of the sheet. For example, compatibilizers include, but are not limited to, maleic anhydride grafted polyolefin (MAH-g-PO/PP/PE), epoxy modified polyolefin, and the like, and coupling agents include, but are not limited to, gamma-aminopropyl triethoxysilane, and the like.

In some embodiments, the inorganic filler is selected from one or more of barium sulfate, titanium white, talc, bentonite, quartz sand, alumina, calcium carbonate, glass frit, zinc oxide. In this embodiment, the inorganic filler can increase the strength and filling ability of the hot melt resin material, and the inorganic filler of this embodiment can also better contact the surfaces of the positive and negative electrode active materials and the polymer binder, and is easier to penetrate to form a stable contact.

In some embodiments, the particle size of the inorganic filler is 20-50 nm, and the inorganic filler is one or more selected from barium sulfate, titanium white, talcum powder, bentonite, quartz sand, alumina, calcium carbonate, glass powder and zinc oxide.

Optionally, the inorganic filler comprises alumina nanoparticles with a particle size of 20-50 nm.

Optionally, the inorganic filler is 1-60 parts by weight. Alternatively, the inorganic filler is 1 part, 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 50 parts or 60 parts, or any part in the range of 1 to 60 parts.

Optionally, the hot melt resin material comprises, by weight, 50-80 parts of matrix resin, 6-10 parts of compatibilizer, 2-3 parts of coupling agent and 10-50 parts of inorganic filler.

Optionally, the hot melt resin material comprises, by weight, 60-80 parts of matrix resin, 8-10 parts of compatibilizer, 2-3 parts of coupling agent and 10-30 parts of inorganic filler.

Optionally, the hot melt resin material comprises, by weight, 70 parts of a matrix resin, 10 parts of a compatibilizer, 3 parts of a coupling agent and 17 parts of an inorganic filler.

In the battery cell of the embodiment of the present disclosure, the package structure 20 is obtained by curing a package material. The permeability of the encapsulating material is positively correlated with the heating temperature of the encapsulating material, i.e. the higher the heating temperature, the better the flowability of the encapsulating material and the better the permeability.

In the battery cell of the embodiment of the present disclosure, specific structures and compositions of the negative electrode tab 11, the solid electrolyte layer 12, and the positive electrode tab 13 are not limited, and are determined according to actual conditions.

Alternatively, one negative electrode tab 11 includes a negative electrode active material layer 111 and a negative electrode current collector layer 112, the negative electrode active material layer 111 being disposed on the negative electrode current collector layer 112. Wherein, one or both sides of the negative electrode current collector layer 112 are covered with a negative electrode active material layer 111, which is determined according to actual requirements.

In the present embodiment, the anode current collector layer 112 is generally composed of a metal material. Optionally, the material of the negative electrode current collector layer 112 includes copper foil. The thickness of the negative electrode current collector layer 112 may be controlled to be 6-10 μm, and optionally, the thickness of the negative electrode current collector layer 112 is 6-8 μm. Optionally, the negative electrode current collector layer 112 includes a copper foil having a thickness of 6 to 10 μm.

The anode active material layer 111 is not limited and is determined according to actual demands. Alternatively, the anode active material layer 111 includes an anode active material and other additive materials including one or more composites of pure silicon material, graphite material, carbon material, silicon carbon material, and silicon oxygen material.

Optionally, a negative electrode tab includes a negative electrode active material layer. That is, the anode tab of the present embodiment is composed of only the anode active material layer 111, and the anode active material layer 111 is designed to reversibly contain and release lithium ions and can function as external conduction, and the anode current collector layer 112 is not required to provide a conduction function. At this time, the anode active material layer 111 is composed of one or more compounds of conductive materials such as lithium metal and carbon material.

Alternatively, one positive electrode tab 13 includes a positive electrode active material layer 131 and a positive electrode current collector layer 132, and the positive electrode active material layer 131 is disposed on the positive electrode current collector layer 132. One or both sides of the positive electrode current collector layer 132 are covered with a positive electrode active material layer 131, which is determined according to actual requirements.

In the present embodiment, the positive electrode current collector layer 132 is generally composed of a metal material. Optionally, the material of the positive electrode current collector layer 132 includes aluminum foil. The thickness of the positive electrode current collector layer 132 may be controlled to be 6 to 20 μm, and optionally, the thickness of the positive electrode current collector layer 132 is 10 to 20 μm. Optionally, the positive electrode current collector layer 132 includes an aluminum foil having a thickness of 10 to 20 μm.

Optionally, the positive electrode active material layer 131 is composed of one or more compounds of lithium cobaltate, lithium nickelate, lithium manganese oxide, lithium manganate, lithium-rich manganese base, lithium iron phosphate, lithium nickel cobalt aluminate, lithium nickel cobalt manganate, lithium iron phosphate, lithium vanadium phosphate, sulfur, lithium sulfide, and sulfur iodide as a main component.

In the battery cell of the embodiment of the present disclosure, the solid electrolyte layer 12 connects the anode active material layer 111 and the cathode active material layer 131 to each other, providing a role of lithium ion transport. The solid electrolyte layer 12 is obtained by compounding one or more of sulfide electrolyte, oxide electrolyte, polymer electrolyte, and halide electrolyte. Preferably, the solid electrolyte layer 12 is a sulfide electrolyte selected from one or a combination of several of lithium phosphorus chlorosulfide, lithium phosphorus bromosulfide, lithium phosphorus iodized sulfide, lithium phosphorus silicon sulfide, lithium phosphorus aluminum sulfide, lithium phosphorus germanium sulfide, lithium phosphorus boron sulfide, lithium phosphorus sulfide, lithium silicon sulfide, and lithium silicon indium sulfide.

Referring to fig. 5, an embodiment of the disclosure provides a method for packaging a battery cell, including the following steps:

S110, stacking the positive electrode plate, the negative electrode plate and the solid electrolyte layer in the sequence of the positive electrode plate, the solid electrolyte layer, the negative electrode plate and the solid electrolyte layer to obtain a lamination structure, wherein a sheet gap is formed on the peripheral side surface of the lamination structure.

And S120, setting an encapsulation material in the sheet gap of the lamination structure to obtain the battery core with the encapsulation structure, wherein the encapsulation material can permeate into the sheet layer around the sheet gap to form a permeation part.

In the method for packaging the battery cell, the positive electrode plate, the negative electrode plate and the solid electrolyte layer are stacked according to a specific sequence to obtain a lamination structure, and then packaging materials are arranged in a sheet gap of the lamination structure. Compared with the existing method requiring insulation treatment on a single sheet (such as a positive electrode sheet), the battery cell packaging method disclosed by the embodiment of the invention has more practicability, can use continuous coating electrode sheets, is compatible with overhang designs and sizes of positive electrode sheets and negative electrode sheets and the like, can simplify the edge short-circuit prevention treatment of the single electrode sheet into edge short-circuit prevention packaging of a lamination structure, and greatly reduces the manufacturing process difficulty, period and cost of the battery.

In the method for packaging a battery cell in the embodiment of the present disclosure, in step S110, the positive electrode sheet, the solid electrolyte layer, and the negative electrode sheet may be obtained by conventional methods, which is not limited herein. The sizes of the positive pole piece and the negative pole piece can be designed to be equal in size, or the design that at least one side of the circumference of the negative pole piece is larger than overhang of the positive pole piece.

In step S120, the manner in which the encapsulating material is provided in the sheet voids of the lamination structure is not limited as long as the encapsulating paste can be provided in the sheet voids and penetrate into the peripheral sheets thereof. In some embodiments, disposing the encapsulation material into the sheet voids of the lamination structure includes disposing the encapsulation material into the sheet voids of the lamination structure using a 3D printing method, a potting method, or a filling method.

Optionally, the encapsulation material is printed and arranged into the sheet gaps of the lamination structure by adopting a 3D printing method. Compared with other modes, the cell edge packaging of the laminated solid-state battery is performed through a 3D printing technology, the deposited material quantity can be accurately controlled, and when the packaging material is introduced into the peripheral side surface of the laminated structure and the sheet gaps, a proper amount of the packaging material can be accurately conveyed according to the requirements of different positions. Meanwhile, the non-contact 3D printing manufacturing technology can not cause mechanical damage to the polar plate. In addition, the 3D printing method can construct a supporting structure in the micron-sized gap, so that the filling rate of the interlayer gap and the packaging material can be effectively ensured to penetrate into the inside of the sheet gap and the peripheral sheet of the sheet gap, and the problem of edge stress concentration in the solid-state cell pressurizing manufacturing or high-voltage operation process is more effectively solved. In addition, the 3D printing method has high processing efficiency and high material utilization rate, and can solve the problems of permeability and overflow prevention of the fluid packaging material in the printing process. In the embodiment of the disclosure, the 3D printing method is not limited, and the printing path, the printing parameters, and the like are set according to actual situations.

In some embodiments, disposing an encapsulation material into the sheet voids of the lamination structure in step S120 includes disposing a first permeable encapsulation material into the sheet voids of the lamination structure to obtain a first lamination structure having a first encapsulation layer, wherein the first encapsulation layer has a penetration portion penetrating into the sheet layer around the sheet void and a first filling portion located in the sheet void, and a thickness of the first filling portion is less than a depth of the sheet void. And arranging a second permeable packaging material in the sheet gap of the first lamination structure, and obtaining a second packaging layer outside the first packaging layer to obtain the packaging lamination structure, wherein the outer surface of the second packaging layer is level with the peripheral side surface of the lamination structure, or the second packaging layer protrudes out of the peripheral side surface of the lamination structure and forms a coating part for coating the peripheral side surface of the lamination structure, and the permeability of the second permeable packaging material is smaller than that of the first permeable packaging material.

The cell packaging method of this embodiment is defined as a dynamic regulation packaging method, firstly, a first permeable packaging material with better permeability is adopted for filling, so that the packaging material can infiltrate into the peripheral sheet layers of the sheet layer gaps, and then a second permeable packaging material with low permeability is adopted to continuously and completely fill the sheet layer gaps, so that the depth of the packaging material infiltrated into the sheet layer can be controlled controllably, the interface bonding effect of deep penetration is ensured, and the edge overflow defect is avoided, so that the compact pore-free packaging structure 20 is formed.

In this embodiment, the first permeable sealing material and the second permeable sealing material may be the same material or different materials. For example, the first and second permeable sealing materials are both made of the aforementioned hot melt resin materials.

The penetrability of the first and second penetrable sealing materials may be achieved by heating the materials, i.e., the first and second penetrable sealing materials employ a resin material whose penetrability (flowability) can vary depending on the temperature. Optionally, the first permeable encapsulation material is an encapsulation material heated to a first temperature, and the second permeable encapsulation material is an encapsulation material heated to a second temperature, the first temperature being greater than the second temperature. In this embodiment, the first temperature and the second temperature are selected from temperature values within a melting point range of the encapsulation material. Optionally, the first temperature is selected from a first sub-temperature range near the high temperature end of the melting point range of the encapsulation material, and the second temperature is selected from a second sub-temperature range near the low temperature end of the melting point range of the encapsulation material. The first sub-temperature range and the second sub-temperature range may have a partial overlap.

Optionally, the first permeable packaging material is obtained by heating the hot-melt resin material to 80-100 ℃, and/or the first permeable packaging material is obtained by heating the hot-melt resin material to 60-85 ℃. The hot-melt resin material is heated to a melting point to be melted into a fluid.

In the dynamic regulation packaging method of the embodiment, the regulation of the permeability of the packaging material is involved in the packaging process, for example, the regulation of the permeability of the packaging material is realized by regulating the temperature, so that a device/equipment capable of regulating the discharging temperature can be used for packaging.

Optionally, a 3D printing method or a pouring method is used to dynamically regulate the packaging method. In this embodiment, a 3D printing device or a glue filling machine is used to perform a dynamic adjustment and encapsulation method.

In an example, a 3D printing device is used to set an encapsulation material into the sheet gaps of the lamination structure through a 3D printing method, so as to perform a dynamic regulation encapsulation method. The 3D printing apparatus may employ a 3D printing apparatus including one discharge head (e.g., a single-head 3D printing apparatus) or a plurality of discharge heads (e.g., a multi-head 3D printing apparatus). Optionally, a multi-nozzle 3D printing device is used for setting packaging materials in the sheet gaps of the lamination structure to perform dynamic regulation packaging, wherein a first material outlet head (a first printing head) is used for outputting the first permeable packaging materials, and a second material outlet head (a second printing head) is used for outputting the second permeable packaging materials. In the 3D printing process, a printing path and printing parameters (e.g., printing speed, layer height, line width, printhead aperture, etc.) are determined according to the depth and width of the sheet gap and the actual conditions of the encapsulation material, etc., and are not limited. For example, the printing speed is 25 to 45 mm/s, the layer height is 10 to 30 μm, and the line width is 80 to 120 μm.

In the 3D dynamic adjustment packaging method in this embodiment, the printing paths of the first permeable packaging material and the second permeable packaging material may be the same or different. Optionally, the print path of the first permeable encapsulation material is a loop-shaped track and the print path of the second permeable encapsulation material is a straight track.

In another example, a potting machine is used to set a potting material into the sheet voids of the lamination stack by a potting method to dynamically regulate the potting method. The glue-pouring machine can adopt a glue-pouring machine comprising one discharging head (for example, a single-nozzle glue-pouring machine) or a plurality of discharging heads (for example, a multi-nozzle glue-pouring machine). Optionally, a multi-nozzle glue filling machine is adopted to set packaging materials in the sheet gaps of the lamination structure for dynamic regulation and control packaging, wherein a first material outlet head (a first glue outlet needle head) is used for outputting the first permeable packaging materials, and a second material outlet head (a second glue outlet needle head) is used for outputting the second permeable packaging materials. In the pouring process, pouring parameters (such as pouring speed, discharging amount, discharging head aperture and the like) are determined according to the depth and width of the sheet gap, the packaging material and other practical conditions, and are not limited.

Different discharge heads adopt different heating temperatures, the discharge heads are matched with a printing path to rotate, different discharge heads can be connected with different charging barrels, packaging materials with different formulas can be arranged in different charging barrels, the high-permeability hot-melt resin discharge heads are connected for printing/pouring at the initial use, the connection strength between the packaging structure and the edge of the battery cell is enhanced, the discharge heads connected with the low-permeability and low-fluidity hot-melt resin materials are used for processing at the subsequent use, and the casting of the edge is avoided.

In some embodiments, disposing the encapsulation material into the ply-voids of the lamination structure in step S120 includes disposing the encapsulation material into the ply-voids of the lamination structure layer by layer. In this embodiment, a layered arrangement mode is adopted, so that the thickness and uniformity of the packaging structure can be conveniently controlled. The present embodiment can be performed by employing a 3D printing method or a priming method.

The layered arrangement mode of the embodiment can be combined with the dynamic regulation and control packaging method, that is, the arrangement of the first permeable packaging material and the second permeable packaging material respectively adopts the layered arrangement mode of the embodiment.

Optionally, the packaging material comprises packaging material with permeability positively correlated with temperature, and the packaging material is arranged in the sheet gaps of the lamination structure, wherein the packaging material is arranged layer by layer in the sheet gaps of the lamination structure, and the heating temperature of the packaging material is reduced from the inner layer to the outer layer. The present embodiment can be performed by employing a 3D printing method or a priming method. In this embodiment, the heat-fusible material is heated at a higher temperature or a higher-permeability heat-fusible material is used to improve fluidity to better fill the voids and the permeable material areas when the peripheral side of the laminated cell (i.e., lamination structure) is printed for the first time, and the heat-fusible material is heated at a lower temperature or a lower-permeability heat-fusible material is used to reduce fluidity to prevent overflow when printing in a thickened manner. Namely, by adopting a dynamic temperature adjustment cell packaging method, the penetration of the packaging structure 20 into the sheet layer can be better realized, and the fluidity of the packaging material is adjusted and controlled by heating temperature, so that the penetration capacity is adjusted, the penetration depth of the penetration part 210 can be controllably adjusted, and the improvement of the battery performance is ensured.

In the method for packaging the battery cell, in step S120, the method further comprises the steps of obtaining permeation information capable of reflecting permeation conditions of the packaging material while setting the packaging material into a sheet gap of the lamination structure, and adjusting the permeation capacity of the packaging material according to the permeation information. In this embodiment, the self-adaptive regulation and control of the permeability (fluidity) of the packaging material is realized by feeding back the permeation condition of the packaging material in real time, so that the permeation depth of the packaging material can be effectively controlled, and further, the improvement of the battery performance is ensured.

Optionally, the infiltration information capable of reflecting the infiltration of the first permeable encapsulation material includes infrared imaging image information. The embodiment is matched with infrared imaging to monitor the flowing state and path of the packaging material (hot melt resin material) in real time, and dynamically adjusts the heating temperature.

In the packaging method of the embodiment of the disclosure, in the process of setting the packaging material in the sheet layer gap, the packaging material begins to cool and solidify, and after packaging is completed, the packaged lamination structure (the lamination structure provided with the packaging material) is continuously placed for a period of time, and solidified and molded, so as to obtain the battery cell with the packaging structure.

In some embodiments, step S120, after disposing the encapsulation material into the void region of the lamination stack, further comprises the step of subjecting the lamination stack with the encapsulation material disposed therein to a heat press process. In the embodiment, the lamination structure provided with the packaging material is subjected to hot-pressing treatment so as to strengthen the combination of the packaging material (for example, hot-melt resin material) and the pole piece edge cavity, refill microscopic pits (such as cracks smaller than 5 μm) on the surface of the pole piece, reduce the interfacial void ratio, and meanwhile, by adding the hot-pressing step, the contact of each solid-solid interface in the battery core can be improved, and the poor contact interface is repaired, so that the problem of lithium dendrite growth is relieved, the ion transmission path is shortened and the like. The autoclave treatment of the present embodiment may be defined as a secondary curing treatment.

Optionally, the hot pressing of the lamination structure provided with the packaging material comprises placing the lamination structure provided with the packaging material on a heating plate with a first preset temperature and processing the first preset time. The thermocompression process of this embodiment is described as a first thermocompression process in which the pressure is the self pressure of the lamination structure in which the encapsulation material is provided.

Optionally, the lamination structure provided with the packaging material is subjected to hot pressing treatment, which comprises the steps of placing the lamination structure provided with the packaging material on a heating plate with a first preset temperature, applying vibration, and treating for a second preset time. The autoclave treatment of this example was noted as a second autoclave treatment.

Optionally, the lamination structure provided with the packaging material is subjected to hot pressing treatment, which comprises the steps of placing the lamination structure provided with the packaging material on a heating plate with a first preset temperature, applying pressure and treating for a second preset time. The autoclave treatment of this embodiment is described as a third autoclave treatment.

Optionally, the lamination structure provided with the packaging material is subjected to hot pressing treatment, which comprises the steps of placing the lamination structure provided with the packaging material on a heating plate with a first preset temperature, applying pressure and vibration, and treating for a second preset time. The autoclave treatment of this example was noted as a fourth autoclave treatment.

In the first to fourth hot pressing processes, the first preset temperature may be such that the encapsulation material is softened again to have a certain fluidity. It is understood that the heating plate is provided with a heating groove, and the groove body of the heating groove is consistent with the outer contour of the lamination structure provided with the packaging material. The lamination structure of the packaging material is arranged in the heating tank, so that the lamination structure can be limited on the inner wall of the tank body of the heating tank, namely, the sliding dislocation of the sheet layer can be avoided when pressure is applied, and the packaging material softened by reheating can be prevented from flowing out of the gap of the sheet layer. Optionally, the first preset temperature is greater than or equal to T _min and less than or equal to T ', T' =t _min+δ×（T_max-T_min, where T _max is an upper limit value of the melting point range of the packaging material, T _min is a lower limit value of the melting point range of the packaging material, and the value range of δ is [0,1/3]. The specific value of delta is determined according to the melting point range of the packaging material, namely, the first preset temperature is the lower limit value of the melting point range of the packaging material or a certain temperature higher than the lower limit value, so that the packaging material is softened and has certain fluidity. Alternatively, δ is 0, 1/5, 1/4, or 1/3, etc.

Optionally, the first preset temperature is 60 ℃ to 70 ℃. Optionally, the first preset temperature is 60 ℃.

Optionally, the first preset time is 20 s-60 s. Optionally, the first preset time is 20 s-50 s. The first preset time is 20 s-40 s. The first preset time is 30s.

Optionally, a hot press device is used to perform hot press treatment on the lamination structure provided with the packaging material, as shown in fig. 7, and a hot press device 30 includes a heating plate 31 and a pressing plate 32, a heating groove 310 is provided on the heating plate 31, and a groove cavity of the heating groove 310 is consistent with an outer contour of the lamination structure provided with the packaging material. The pressurizing plate 32 is movably disposed above the heating plate 31, and the pressurizing plate 32 can be fastened to the heating plate 31 to pressurize the lamination structure placed in the heating slot 310.

Optionally, the bottom of the heating tank 310 is provided with a buffer structure. Flexible support is provided for the lamination stack provided with encapsulation material placed in the heating tank 310, protecting the lamination stack. In this embodiment, the buffer structure may be a buffer pad, for example, a buffer pad having elastic deformability such as a rubber pad, a silicone pad, or a latex pad. Or may be a supporting plate structure connected to the bottom wall of the heating tank 310 through a damping member, which may be a spring.

Optionally, the pressing surface of the pressing plate 32 is provided with a pressing convex surface adapted to the shape of the heating slot 310 for directly pressing the lamination stack placed in the heating slot 310.

Optionally, a pressure sensor is provided on the pressure plate 32 to feed back in real time the pressure applied to the lamination stack. Ensuring that the proper pressure is applied. Alternatively, the pressure sensor is provided on a pressing convex surface provided on the pressing surface of the pressing plate 32.

During hot pressing, proper pressure is applied to promote the flowing filling of the packaging material, promote the interaction between the packaging material and active substances, adhesive and the like in the pole piece, and improve the binding force.

Alternatively, the means of applying pressure may include applying a constant pressure, or applying a gradient pressure.

Optionally, the constant pressure is selected from 0.3-0.5 MPa.

Alternatively, the gradient pressure is applied in such a way that the pressure gradient increases. Optionally, the gradient pressure is in a pressure range of 0.3-3 MPa. Optionally, applying the gradient pressure comprises applying a low pressure of 0.3-0.5 MPa for a first preset time, and then increasing the pressure to a high pressure of 1-3 MPa for the first preset time.

During hot pressing, vibration is increased, the encapsulation material is further induced to permeate to the edge pore of the electrode plate in a positioning way, the adhesion strength of an interface is increased, and the problem of breakage and material dropping caused by uneven stress of an edge material area is avoided. Optionally, the vibration comprises vibration having a frequency of 10-50 Hz and an amplitude of less than or equal to 50 μm, with the vibration applied.

Alternatively, in the case of applying vibrations, the vibrations include gradient step vibrations. In this embodiment, the gradient step vibration is applied in such a manner that the vibration frequency gradient increases. Optionally, in this embodiment, the gradient step-by-step vibration ranges from 20 Hz to 2000 Hz, and the gradient step-by-step vibration is performed by increasing the frequency from low to high.

Optionally, applying gradient step-by-step vibration includes treating the first preset time under low frequency vibration of 20 Hz to 50 Hz, and then treating the first preset time under high frequency vibration of 500Hz to 2000 Hz.

Optionally, the thermo-compression device 30 further comprises a vibrating structure 311 for applying vibrations to the lamination stack provided on the heating plate 31. The vibration structure form is not limited, and the vibration structure 311 is provided to the heating plate 31 to apply vibration to the lamination stack placed in the heating slot 310.

Alternatively, the vibration structure 311 includes a flexible vibration plate, which is disposed in the heating groove of the heating plate 31, or the heating plate 31 is disposed on the flexible vibration plate. The flexible vibration disk includes a vibration disk having a buffer structure on a disk surface. The output vibration is soft, and the lamination structure is protected.

Optionally, the flexible vibration disk comprises a flexible disk body and a vibration element, wherein a vibration output end of the vibration element is arranged on the flexible disk body to output vibration to the flexible disk body, and a buffer structure is arranged on the disk surface of the flexible disk body. In this embodiment, the vibration element is an element capable of outputting micro-vibrations such as small amplitude/small vibration frequency, for the vibration output object being a laminated cell structure.

Alternatively, the vibration element includes an electromagnetic vibration table, a piezoelectric vibrator, a spring vibration device, a pneumatic vibrator, a hydraulic vibrator, an ultrasonic device, or the like. The vibrating elements are capable of outputting micro-vibrations.

Alternatively, the cushioning structure of the disk surface of the flexible disk may be a cushioning pad, for example, a rubber pad, a silicone pad, a latex pad, or the like having elastic deformability. Or may be a supporting plate structure connected to the bottom wall of the heating tank 310 through a damping member, which may be a spring.

Optionally, performing hot pressing treatment on the lamination structure provided with the packaging material, wherein the hot pressing treatment comprises the steps of applying low pressure of 0.3-0.5 MPa and low-frequency vibration of 20-50 Hz to the lamination structure provided with the packaging material to treat the lamination structure for a first preset time, and then boosting the lamination structure to high pressure of 1-3 MPa and high-frequency vibration of 500-2000 Hz to treat the lamination structure for the first preset time.

In an example, as shown in fig. 6, a 3D printing temperature regulation packaging method includes:

S210, stacking the positive electrode plate, the negative electrode plate and the solid electrolyte layer in the sequence of the positive electrode plate, the solid electrolyte layer, the negative electrode plate and the solid electrolyte layer to obtain a lamination structure, wherein a sheet gap is formed on the peripheral side surface of the lamination structure.

S220, vertically arranging the lamination structure in a printing area of the 3D printing equipment in a mode that the side surface to be printed faces upwards;

S230, acquiring contour entity data of a side surface to be printed of the lamination structure, acquiring a contour three-dimensional model according to the contour entity data, slicing the contour three-dimensional model, planning a path and designing printing parameters to obtain printing information;

s240, the 3D printing equipment prints and sets the melted packaging material heated to the preset temperature on the side to be printed according to the printing information and the heating temperature of the packaging material, and completes packaging and printing of the side to be printed of the lamination structure, so that the lamination structure provided with the packaging material is obtained.

In this embodiment, the side to be printed of the lamination structure is one side of the peripheral sides of the lamination structure, and the steps are repeated to print packages one by one, so as to complete the package of the lamination structure.

In step S230 of the present embodiment, the physical contour data of the side to be printed includes data capable of representing the key structural nodes such as the edges, the slices, and the slice gaps of the side to be printed. Optionally, acquiring the physical contour data of the side to be printed of the lamination structure comprises adopting a high-precision visual scanner or a three-dimensional scanner to scan the side to be printed of the lamination structure, and simultaneously combining the physical parameters of the lamination structure to acquire the physical contour data of the side to be printed. Wherein lamination stack physical parameters include the size of the lamination stack, the number of lamination layers, etc. The sides of the lamination stack are not flush with the sheet gaps, and thus the solid profile data comprises three-dimensional solid data.

In step S230, a contour three-dimensional model is obtained according to the contour entity data, which comprises the steps of importing entity contour data of a side to be printed into three-dimensional modeling software for modeling to obtain the contour three-dimensional model. The three-dimensional modeling software is not limited, for example MeshLab, blender, etc., and the entity profile data can be processed in the modeling process, including removing noise, filling holes, optimizing grids, etc., without limitation.

Optionally, in step S230, the three-dimensional model of the contour is sliced by slicing software, where the slicing software generates printing information according to the shape, size and printing parameters of the model. The printing parameters include print layer height, packing density, print speed, printhead temperature, print bed temperature, etc. The printing information includes a printing path that determines a moving track of the print head, and printing parameters including a printing speed, an extrusion amount of material, a printing layer height, a material heating temperature, a print head temperature, and the like. Wherein the print path is output in the form of a G-code instruction recognizable by the 3D printing apparatus.

Optionally, slicing software includes Cura, prusaSlicer, etc.

It will be appreciated that the peripheral side of the lamination stack comprises 4 sides of different direction, each side being the side to be encapsulated.

Optionally, the solid contour data of the side to be printed acquired in the step S230 is the solid contour data of the side to be printed currently facing upwards in the step S220, and the printing path acquired in the step S230 is the printing path of the side to be printed currently facing upwards, and the 3D printing temperature regulation packaging method further includes repeating the steps S220 to S240, packaging and printing the sides to be printed of the lamination structure one by one, completing packaging of the lamination structure, and obtaining the packaging lamination structure. In the embodiment, in step S220, when packaging is performed for different sides to be printed, the upward side to be printed needs to be adjusted. For example, the lamination stack is rotated so that the side to be printed faces upward.

Optionally, the solid profile data of the side to be printed acquired in step S230 is solid profile data of the entire peripheral side of the lamination structure in step S210, and the print paths acquired in step S230 are print paths of all the side to be printed of the entire peripheral side. And when packaging the different sides to be printed, adjusting the current side to be printed to face upwards. For example, the lamination stack is rotated so that the side to be printed faces upward.

Optionally, in step S240, the method further comprises regulating and controlling the heating temperature of the packaging material. Specifically, the simultaneous regulation of the heating temperature of the packaging material comprises the steps of regulating the heating temperature of the packaging material according to the acquired permeation information capable of reflecting the permeation condition of the packaging material and regulating the heating temperature of the packaging material according to the permeation information. In this embodiment, the penetration condition of the packaging material is fed back in real time, so that the self-adaptive regulation and control of the heating temperature (i.e., penetration capability and fluidity) of the packaging material is realized, the penetration depth of the packaging material can be effectively controlled, and further, the improvement of the battery performance is ensured.

In some embodiments, the 3D printing temperature regulation packaging method further comprises the step of performing hot pressing treatment on the lamination structure provided with the packaging material, wherein the step of performing hot pressing treatment is performed on the lamination structure. In this embodiment, the related content of the autoclave is referred to the related content, and will not be described herein.

In the method for packaging the battery cell according to the embodiments of the present disclosure, after packaging is completed, for example, after step S240 or step S250, a lamination structure provided with a packaging material may be further subjected to compression processing, for example, isostatic pressing, so that each of the sheets in the lamination structure is connected by pressing.

In the packaging method of the embodiment of the disclosure, the lamination structure is arranged in the 3D printing equipment, and the operation of placing the printed lamination structure provided with the packaging material in the hot pressing device can be completed manually or determined according to actual conditions by the automatic conveying device.

Referring to fig. 8, an embodiment of the disclosure provides a system for packaging a battery cell, where the method for packaging a battery cell in any of the foregoing embodiments includes:

The fluid material precision coating apparatus 41. The fluid material precision coating apparatus 41 includes a 3D printing apparatus or a glue dispenser.

A transfer and positioning module (not shown) for transferring the lamination stack completed to the working area of the fluid material precision coating apparatus 41 after turning the lamination stack to the vertical. Here, the working area refers to an area where coating is performed, for example, a printing area of a 3D printing apparatus, a priming area of a glue dispenser.

A scanning module 42 for scanning contour entity data of a side to be printed of a lamination structure provided at a working area of the fluid material precision coating apparatus 41;

A control unit 43 that obtains a contour three-dimensional model from the contour entity data, performs slicing processing on the contour three-dimensional model, performs path planning and coating parameter (e.g., printing parameter) design, and obtains coating information (e.g., printing path and printing parameter);

The fluid material precision coating apparatus 41 receives coating information (e.g., printing path and printing parameters) of the control unit 43, and sets (e.g., prints or infuses) the melted encapsulation material heated to a preset temperature on the side to be printed of the lamination structure located in the working area according to the coating information, so that the encapsulation material can infiltrate into the inside of the sheet layer around the sheet layer gap to form an infiltrated part. Thereby forming the package structure 20 on the peripheral side of the lamination stack 10.

According to the packaging system of the embodiment, automatic transmission between the lamination process of the lamination structure and the 3D printing equipment is realized by arranging the transmission and positioning module, and automation of the packaging system is realized. The specific configuration of the transfer and positioning module is not limited, and for example, the transfer and positioning module includes a robot.

Optionally, the transfer and positioning module comprises a manipulator, the manipulator end comprising a flexible clamp for clamping the lamination stack. The flexible clamp is a clamp with a buffer structure arranged on the clamping surface. Alternatively, the cushioning structure may be a cushioning pad, for example, a rubber pad, a silicone pad, a latex pad, or the like having elastic deformability. The lamination structure is protected by a certain buffering force in the clamping process.

Optionally, the flexible clamp is rotatable relative to the body of the manipulator. Under the condition that the manipulator main body is not moved, the flexible clamp rotates to realize the rotation of the lamination structure, so that different sides to be printed of the lamination structure are adjusted to face upwards in the packaging procedure of the packaging method. In the present embodiment, the manner in which the flexible jig can be rotated with respect to the robot is not limited.

Alternatively, the scanning module 42 employs a high-precision vision scanner.

In the battery cell packaging system of the present embodiment, the coating information obtained by the control unit 43 includes a coating path and coating parameters. Alternatively, the control unit 43 may be configured to perform the aforementioned step S230 to obtain the print information including the print path and the print parameters.

In some embodiments, the fluid material precise coating device 41 comprises a 3D printing device, the coating information obtained by the control unit 43 comprises a printing path and printing information, the printing information comprises one or more of a loop track and/or a straight track, a line width of 80-120 mu m, a layer height of 5-20 mu m, a printing speed of 25-45 mm/s, a heating temperature in a melting point range of the packaging material, and a printing head temperature of 1-50 ℃ higher than the heating temperature;

optionally, when the encapsulating material is the hot-melt resin material, the heating temperature in the printed information is 60-100 ℃.

Optionally, when the foregoing dynamic regulation packaging manner is implemented by the electrical core packaging system, the heating temperature includes a first heating temperature and a second heating temperature, where the first heating temperature is greater than the second heating temperature, and the first heating temperature is a heating temperature of the first permeable packaging material, and the second heating temperature is a heating temperature of the second permeable packaging material. For example, the first heating temperature is selected from 80 ℃ to 100 ℃, and the second heating temperature is selected from 60 ℃ to 100 ℃.

Optionally, when the foregoing dynamic regulation packaging manner is implemented by the electrical core packaging system, the printing information may further include a printing temperature curve, and according to the printing temperature curve, the heating temperature and the corresponding printhead temperature are synchronously adjusted.

In some embodiments, the packaging system of the battery cell further comprises a hot pressing device (as shown in fig. 7), wherein the hot pressing device is used for performing hot pressing treatment on the lamination structure provided with the packaging material, and the conveying and positioning module is further used for conveying the printed lamination structure provided with the packaging material to the hot pressing device for performing hot pressing treatment.

In some embodiments, the transmitting and positioning module is further configured to transmit the packaged battery cell with the packaging structure to a subsequent process.

It will be appreciated that the robot end of the transfer and positioning module may also include suction cups, and that after the lamination is encapsulated, the encapsulated lamination may be picked up and transferred using a pick-up end such as a suction cup. And the conveying is convenient.

In some embodiments, the packaging system of the battery cell further comprises an infrared scanning device, wherein the infrared scanning device is used for performing infrared imaging scanning monitoring on the gap of the sheet layer while setting the packaging material in the gap of the sheet layer of the lamination structure so as to obtain infrared imaging image information, and can reflect permeation information of the permeation condition of the packaging material.

Specific embodiments are given below to specifically illustrate the battery cell, the packaging method, the packaging system, the solid-state battery and the hot-melt resin material according to the embodiments of the present disclosure, so as to more clearly illustrate the technical problems, the technical solutions and the beneficial effects that the present application solves. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses.

The examples are not to be construed as limiting the specific techniques or conditions described in the literature in this field or as per the specifications of the product. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

Example 1

A battery cell includes a lamination structure and a package structure. The lamination structure comprises alternately stacked negative pole pieces and positive pole pieces, and a solid electrolyte layer is arranged between the adjacent positive pole pieces and negative pole pieces, wherein at least one side of the circumference of the negative pole pieces exceeds the positive pole pieces to form overhang areas, and the circumferential side surface of the lamination structure forms a suspension gap corresponding to overhang areas. The packaging structure comprises a filling part, a penetrating part and a coating part, wherein the filling part is arranged in a suspension gap of the lamination structure, the penetrating part extends to penetrate into a part in the sheet layer around the suspension gap by the filling part, and the coating part is connected with the filling part and coats the peripheral side surface of the lamination structure.

Referring to fig. 1 and 2, the battery cell of embodiment 1 includes a plurality of lamination units, and both surfaces of the lamination structure 10 are negative electrode tabs.

In the battery cell of embodiment 1, the package structure is formed by filling the suspension gap with the molten hot-melt resin material and partially penetrating into the sheet layer to be solidified. The hot melt resin material comprises, by mass, 70 parts of matrix resin, 10 parts of compatibilizer, 3 parts of coupling agent and 17 parts of inorganic filler, wherein the matrix resin is ethylene-vinyl acetate copolymer (EVA), the compatibilizer is maleic anhydride grafted polyolefin (MAH-g-PP/PE), the silane coupling agent is gamma-aminopropyl triethoxysilane, and the inorganic filler is alumina nanoparticles of 20-50 nm. The melting point of the hot melt resin material is 60-100 ℃, the melt index is 200-400 g/10 min, the melt viscosity is 2000-12000 mPa.s, and the contact angle between the hot melt resin material and the surface of a battery pole piece is less than or equal to 60 degrees.

In this example 1, for the subsequent solid-state battery assembly and battery performance test, the following negative electrode tab, positive electrode tab, and solid-state electrolyte layer were specifically employed.

The negative electrode plate is prepared from a negative electrode active material layer by adopting a wet process, wherein the negative electrode active material layer comprises micron silicon, PVDF, VGCF=95:3:2, a negative electrode current collector layer adopts copper foil with the thickness of 6-10 mu m, and the size of the negative electrode plate is 152 mm multiplied by 152 mm. Wherein PVDF is polyvinylidene fluoride, VGCF is vapor grown carbon fiber.

The positive electrode plate is prepared by adopting a dry process, the positive electrode active material layer is composed of NCM (negative electrode metal) LPSCl:SP (polytetrafluoroethylene) and PTFE=85:10:3:2 in mass ratio, and the positive electrode current collector layer is made of aluminum foil with the thickness of 10-20 mu m. The size of the positive electrode sheet was 148 mm ×148: 148 mm. Wherein the NCM material is nickel cobalt lithium manganate material, LPSCl solid electrolyte is sulfur silver germanium ore type electrolyte, SP is conductive carbon black, and PTFE is polytetrafluoroethylene.

The solid electrolyte layer is sulfide electrolyte and is selected from one or a combination of a plurality of lithium phosphorus chlorine sulfur, lithium phosphorus bromine sulfur, lithium phosphorus iodine sulfur, lithium phosphorus silicon sulfur, lithium phosphorus aluminum sulfur, lithium phosphorus germanium sulfur, lithium phosphorus boron sulfur, lithium phosphorus sulfur, lithium silicon sulfur and lithium silicon indium sulfur.

The battery cell of the embodiment 1 is packaged by adopting a 3D temperature regulation packaging method, and the packaging method comprises the following steps:

The lamination operation comprises the steps of superposing a positive electrode plate, a negative electrode plate and a solid electrolyte layer in sequence by adopting a 6 positive electrode 7 negative design, and obtaining a lamination structure, wherein the circumference of the negative electrode plate respectively exceeds a overhang area formed by the positive electrode plate, a overhang area corresponding overhanging gap is formed on the circumferential side surface of the lamination structure, and the width of a overhang area is 2mm.

And vertically arranging the lamination structure in a printing area of the 3D printing equipment in a mode that the side to be printed faces upwards.

And (3) constructing a printing path, namely adopting a high-precision visual scanner (the precision is +/-5 mu m) to perform visual scanning on the side surface to be printed of the lamination structure, identifying the gap position of the lamination (the width of the gap of the lamination is about 200-300 mu m), and simultaneously combining physical parameters of the lamination structure (including the size of the lamination structure and the lamination layer number) to obtain the physical contour data of the side surface to be printed. And importing the solid contour data of the side to be printed into three-dimensional modeling software for modeling to obtain a contour three-dimensional model. Slicing the three-dimensional contour model by slicing software, wherein the slicing software generates printing information according to the shape, the size and the printing parameters of the model. The printing information includes a printing path and printing parameters, and the printing path includes a moving track of the printing head, printing speed of the printing parameters, extrusion amount of the material, printing layer height, material heating temperature, printing head temperature, and the like. Wherein the moving track comprises a loop track, a straight track and the like.

And (3) printing and packaging, namely, the 3D printing equipment adopts a non-contact type hot melting nozzle (aperture 100 mu m) according to printing information and the heating temperature of packaging materials, sets the printing temperature to be 85 ℃ (namely, the heating temperature of the packaging materials), sets the initial extrusion pressure to be 0.4 MPa, fills the sheet gap along the side surface of the lamination structure according to a planned printing path and printing parameters (such as a circular track or a straight track, a line width of 80-120 mu m and a layer height of 20 mu m, and the printing speed of 25-45 mm/s), dynamically adjusts the extrusion pressure and the path according to a model design until the sheet gap is filled, and finally forms a coating layer (namely, the thickness of a coating part) with the thickness of 40 mu m on one side surface of the lamination structure to finish packaging of one side surface of the lamination structure. And rotating the lamination structure to enable the side to be printed to face upwards, repeating the steps, and packaging the side to be printed of the lamination structure one by one to obtain the lamination structure provided with the packaging material.

The lamination is transferred to a hot press device 30 (shown in fig. 7), a pressure of 0.4 MPa is applied, heating is carried out at 60 ℃ for 30 s, a vibration structure 311 (for example, the frequency is 30 Hz, the amplitude is 30 μm) is synchronously started, resin permeation is promoted, the lamination is continuously pressurized to 2MPa after completion, the vibration structure 311 is adjusted to a high-frequency operation mode (for example, 2 kHz), and hot pressing is continuously carried out at a high frequency for 30 s.

And (5) finishing hot-pressing treatment and cooling to obtain the battery cell.

The packaging method of this embodiment 1 may employ a packaging system as shown in fig. 8.

Fig. 9a is a cross-sectional scanning electron micrograph of the cell of this example 1, and fig. 9b is an EDS elemental analysis photograph of the cross-section of the cell of this example 1. As can be seen from FIGS. 9a and 9b, the penetration depth of the molten resin material reaches 200 μm to 300. Mu.m. The slice void filling rate is 91.5% by CT tomography. The interface binding force of the resin and the pole piece is 1.2 MPa (compared with the traditional dipping process of 0.7 MPa) measured by a tensile force tester, the packaged battery cell is tested for 24h under the pressure of 20 MPa, and the edge of the pole piece has no crack.

In the cell of this example 1, the positive electrode sheet size 148 mm ×148 mm, the maximum penetration depth was 300 μm, and assuming complete loss of capacity of the penetrated positive electrode portion, the single layer failure area was 177.6 mm ², accounting for 0.81% of the total area of the single layer positive electrode. The theory capacity exertion decline is only 0.81% even the glue solution permeates into the pole piece, and is far less than the improvement of the actual exertion capacity of the packaging structure to the battery core capacity, and the failure area occupation ratio can be further declined along with the increase of the electrode size, so that the embodiment of the disclosure is particularly suitable for large-size battery cores. Therefore, the penetration of the hot-melt packaging material into the internal substances of the sheet layer, especially the active substances of the sheet and the solid electrolyte layer, is improved through the measures of material design, vibration assistance and the like, so that the stability of the packaging structure is greatly improved.

In this embodiment 1, the processing time of the 3D printing package is less than 1 min, the processing time of the single cell is 10min (including printing and hot pressing treatment), the efficiency of the traditional pole piece-by-piece processing technology is improved by more than 3 times, the material utilization rate is up to 95%, compared with the traditional spraying technology, the material utilization rate is only 60% -70%, the gradient viscosity is difficult to control and the materials are quickly switched in the traditional spraying and dipping technology, so that the permeability and the field forming anti-overflow performance are both considered.

Example 2

In comparison with example 1, in the battery cell of example 2, the dimensions of the negative electrode sheet and the positive electrode sheet are the same, no overhang area is designed, and the circumferential side of the lamination structure forms a dislocation space due to misalignment of the electrode sheets. Wherein, the size of the negative pole piece is 148 mm multiplied by 148 mm, and the size of the positive pole piece is 148 mm multiplied by 148 mm. The remaining steps and parameters were the same as in example 1.

Referring to fig. 3, the cell structure of this embodiment 2 is shown in fig. 3, and the package structure is mainly used for wrapping burrs generated in the die cutting process of the negative electrode current collector layer 112 or the positive electrode current collector layer 132, or filling dislocation gaps generated in the misaligned lamination process, and penetrating and improving bonding strength to the sheet layer to prevent separation of the insulating layer and the cell under high pressure.

Example 3

Compared with the embodiment 1, the difference is that, in the battery cell of the embodiment 2, the positive electrode plate and the negative electrode plate adopt the electrode plates with obvious defects, and the battery cell is assembled, and typical electrode plate defects such as burrs generated by die cutting of a current collector are formed, the electrode plate edge defects are electrode plate edge material shortage or electrode plate edge cracks, the thickness of the electrode plate edge is uneven so that local pressure distribution is unbalanced during pressurization, the electrode plate is warped or broken, the current density distribution of the edge area is uneven due to discontinuous coating, the polarization phenomenon is accelerated by the local high-current area, the charging and discharging efficiency is influenced, the lithium dendrite is possibly generated, and the internal short circuit is also possibly caused by the local exposure of the current collector. The remaining steps and parameters were the same as in example 1.

In this embodiment 3, the battery cells are assembled by using the electrode sheets with obvious defects, and meanwhile, obvious lamination misalignment defects are set in the lamination process section, other processes are consistent with the normal battery cells, and the packaging structure is used for filling the dislocation protrusions 1301 and the dislocation recesses 1302 generated by the misalignment of the lamination, wrapping the burrs 1121 of the current collector and filling the edge defects 1122 of the electrode sheets, so that the survival rate of the solid battery cells is greatly improved, and the production yield and the performance consistency of the battery cells are improved.

Example 4

In contrast to example 1, in the 3D temperature-controlled packaging method for a battery cell of example 4, a dual-needle 3D printing apparatus was used, the dual-needle 3D printing apparatus having two needles with independent temperature control, a first needle (aperture 150 μm) connected to a high-permeability resin cartridge, a formulation of EVA: MAH-g-PP/PE: γ -aminopropyl triethoxysilane: alumina=70:10:3:17 (same as the hot melt resin material of example 1), a heating temperature of 95 ℃ to 85 ℃, a gradient decreasing temperature, an extrusion pressure of 0.6 MPa to 0.3 MPa, a print path of a sheet gap was a loop trace, a line width of 120 μm, a layer height of 20 μm, a print speed of 45 mm/s, a second needle (aperture 100 μm) connected to a low-fluidity resin cartridge, a heating temperature of 85 ℃ to 75 ℃ gradient decreasing temperature before the formulation, an extrusion pressure constant of 0.3 MPa, a coating print path trace was a linear trace, a line width of 80 μm, and a print speed of 20 μm at a layer height of 34 μm. The remaining steps and parameters were the same as in example 1.

The packaging method of the battery cell of the embodiment 4 adopts a dual-print head (i.e. dual-needle) step-by-step printing strategy, realizes the cooperative optimization of cavity depth filling and surface high-precision forming through different permeabilities and liquidity of packaging materials at different heating temperatures, shows that the gap filling rate of a slice layer reaches 99.2 percent (higher than 91.5 percent of the single-needle scheme of the embodiment 1) through CT (computed tomography), and the interface binding force test reaches 1.8 MPa (50 percent higher than the single-needle scheme of the embodiment 1).

Example 5

In comparison with example 4, the cell in example 5 was encapsulated with ethylene-vinyl acetate copolymer (EVA). The remaining steps and parameters were the same as in example 4.

In the method for packaging the battery cell in embodiment 5, a dual-print head (i.e. dual-needle) step-by-step printing strategy is adopted, and the cooperative optimization of cavity depth filling and surface high-precision molding is realized through the different permeabilities and liquidity of the packaging materials at different heating temperatures.

Comparative example 1

Unlike example 1, after lamination is completed, the lamination structure of example 1 is directly transferred to a subsequent assembly process such as isostatic pressing without performing the process steps of printing encapsulation and thermocompression treatment of the lamination structure. The remaining steps and parameters were the same as in example 1.

Comparative example 2

Unlike example 2, after lamination is completed, the lamination structure of example 1 is directly transferred to a subsequent assembly process such as isostatic pressing without performing the process steps of printing encapsulation and thermocompression treatment of the lamination structure. The remaining steps and parameters were the same as in example 2.

Comparative example 3

Unlike example 3, after lamination is completed, the lamination structure of example 1 is directly transferred to the subsequent isostatic pressing and other processes without performing the process steps of printing encapsulation and thermocompression treatment of the lamination structure. The remaining steps and parameters were the same as in example 3.

Comparative example 4

Unlike example 1, after lamination is completed, the lamination structure provided with the encapsulating material obtained by printing and encapsulation is directly cooled and solidified, and then transferred to a subsequent assembly process such as isostatic pressing, without performing the process of the thermocompression treatment of example 1. The remaining steps and parameters were the same as in example 1.

Comparative example 5

Unlike example 1, in the print packaging step, an ethylene-vinyl acetate copolymer (EVA) was used as the hot-melt resin material, and the printing temperature was set to 70 ℃. The remaining steps and parameters were the same as in example 1.

In comparative example 5, an ethylene-vinyl acetate copolymer (EVA) was directly used as an encapsulation material, and no compounding was performed. Fig. 10a is a cross-sectional scanning electron micrograph of the cell of comparative example 5, and fig. 10b is an EDS elemental analysis photograph of the cross-section of the cell of this comparative example 5. As can be seen from fig. 10a and 10b, the package structure formed by EVA packaging and the lamination structure sheet (active material layer) have continuous and straight boundaries, and almost no element diffusion is generated at the interface, only mechanical stacking contact is formed, and the measured interface bonding strength is only 0.5 MPa, and the weaker bonding mode and interface bonding force are likely to be unable to resist the volumetric deformation stress of the battery in the isostatic pressing process or the charge-discharge process, thus forming the problems like deformation, falling-off, etc. of the package structure similar to those of fig. 11a and 11 b.

The above-described battery cells of examples 1 to 5 and comparative examples 1 to 5 were assembled to obtain solid-state batteries, and charge and discharge tests were performed with a charge and discharge interval of 2.1 to 4.3V, a test temperature of 30 ℃, test results shown in table 1 (0.1C cycle), and obtained charge and discharge test performance data shown in table 1.

TABLE 1

The results of the above examples and comparative examples show that the solid-state battery having the package structure can effectively avoid the short circuit of the battery during the press assembly and the press operation, and the yields of the battery cells of examples 1 and 2 added with the package structure are high, while the yields of the battery cells of comparative examples 1 and 2 are very low. Fig. 12 is a charge-discharge curve of the cell in example 1 and comparative example 1, and fig. 13 is a performance of the cell in example 1 and comparative example 1, and it can be seen that the cell performance is poor even if no short circuit is found in the manufacturing process, and the survival rate is low after the cycle, which means that some cells still have short circuits due to edge stress in the cycle, and the capacity performance is poor in the subsequent charge-discharge cycle, which is also caused by micro short circuit in the battery.

Taking example 1 as an example, the yield of the battery cell is improved (from 34% to 75% of comparative example 1) by the 3D printing packaging method, and the single average manufacturing cost of the battery cell is directly reduced by 41%. The annual production 1 GWh solid-state battery production line is used for measurement (single-cell nominal capacity 205 Wh is reduced, the yield is 4,878,049), the production cost per unit cell is reduced by more than 6 hundred million yuan according to the average price of the cell, the yield is improved by 41 percent, the annual production cost is reduced by more than 6 hundred million yuan corresponding to the year, and the 100-week cycle survival rate is 94 percent compared with 64 percent of the comparative example 1 from the aspect of performance evaluation, so that the maintenance cost brought by prolonging the service life of the battery is reduced by 35 to 40 percent.

The embodiment 3 and the comparative example 3 all select the defective pole piece for assembling the battery cell, the battery cell of the comparative example 3 is basically completely invalid, and the battery cell processed in the embodiment 3 can improve the yield of the defective battery cell to 22%, namely, the embodiment of the disclosure solves the problem of the edge defect of part of the pole piece through the insulation packaging of the edge, and plays an important role in improving the yield of the whole pole piece and the yield of the battery cell in the actual production process.

Compared with the embodiment 1, the comparative example 4 lacks a secondary curing hot-pressing step, one of the purposes of the step is to strengthen filling of a cavity by a hot-melting material and avoid incomplete filling of a part of the cavity, the other is to strengthen contact between an insulating structure and the edge of an original bare semi-finished battery cell, and the penetration of resin on the side surface of the battery cell is enhanced by hot pressing and vibration, so that the connection strength of the insulating structure and the battery cell is improved, and the other is to synchronously improve contact of other solid interfaces of the battery cell and repair defects of partial poor contact or surface cracks by high-frequency micro vibration. From the experimental results, although the secondary curing hot-pressing step is lack, the secondary curing hot-pressing step can play a good role in preventing short circuits in the initial cell manufacturing stage, and the initial cell manufacturing yield is still high, as the circulation is carried out, the volume change and other stress of the solid-state cell can possibly cause the falling of an insulating structure, so that the edge short circuit prevention measures are lost, and the survival rate of the cell after the circulation is reduced. From the aspect of electrical performance data, the capacity of the battery core can be improved to a small extent through high-frequency micro-vibration to exert the performance.

Through the detailed explanation of the embodiment of the application, the edge short-circuit prevention packaging method for the solid-state battery provided by the application can be clearly recognized, and the key problem of edge short circuit of the solid-state battery, which is caused by overhang design in the design level, is solved radically and efficiently and accurately. The method solves the core problem, and simultaneously fully considers various defects possibly left in the previous working procedures of pole piece manufacture, lamination and the like, such as the defects of the edge of the pole piece, burrs generated by the edge of the foil, misalignment generated in the lamination process and the like, and effectively compensates the defects through reasonable and efficient packaging design. Meanwhile, the hot-melt material provided by the embodiment has excellent high permeability, can quickly and fully permeate into each fine part at the edge of the battery core, is tightly combined with the structure of the battery core, and effectively relieves the stress generated in the battery in the actual running process of the solid-state battery by utilizing the elastic characteristic of the resin material, so that the risk of performance degradation or damage of the battery caused by the stress problem is greatly reduced. Through practical verification, the method remarkably improves the yield of the battery cell manufacturing, has excellent performance in the aspect of battery cell performance, and further enhances the stability, safety and service life of the battery cell. In summary, the embodiments of the present application achieve excellent technical effects in solving overhang short-circuit key problems, making up for defects in previous processes, relieving operation stress, and improving manufacturing yield and cell performance.

In the embodiment of the disclosure, the method for judging the yield of the battery cells is that the open circuit voltage is matched with a design value of +/-0.05V, and the direct current internal resistance is equal to or less than 5% of the battery cells with the same type.

In the examples of the present disclosure, the melting point of a hot melt type resin material was measured using Differential Scanning Calorimetry (DSC), the melt index was measured using a melt index meter, and the viscosity of the material at 180 ℃ was measured using a rotational viscometer as the melt viscosity of the material. The contact angle was measured using a high temperature contact angle meter at 90 ℃.

The design capacity of the cells of examples 1-5 of the presently disclosed embodiments is 5 Ah.

In the embodiment of the disclosure, the step of assembling the battery cell into the solid-state battery comprises isostatic pressing, tab welding and final packaging. Wherein, the isostatic pressure parameter in the assembly process is 500MPa and 15min, and the other assembly processes adopt conventional operation.

The above description and the drawings illustrate embodiments of the disclosure sufficiently to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. Moreover, the terminology used in the present application is for the purpose of describing embodiments only and is not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a," "an," and "the" (the) are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this disclosure is meant to encompass any and all possible combinations of one or more of the associated listed. Furthermore, when used in the present disclosure, the terms "comprises," "comprising," and/or variations thereof, mean that the recited features, integers, steps, operations, elements, and/or components are present, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Without further limitation, an element defined by the phrase "comprising one..+ -." does not exclude the presence of additional identical elements in a process, method or apparatus comprising said element. In this context, each embodiment may be described with emphasis on the differences from the other embodiments, and the same similar parts between the various embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method sections disclosed in the embodiments, the description of the method sections may be referred to for relevance.

Those of skill in the art will appreciate that the elements and steps of the examples described in connection with the embodiments disclosed herein can be implemented as electronic hardware, or as a combination of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. The skilled artisan may use different methods for each particular application to achieve the described functionality, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than that disclosed in the description, and sometimes no specific order exists between different operations or steps. For example, two consecutive operations or steps may actually be performed substantially in parallel, they may sometimes be performed in reverse order, which may be dependent on the functions involved. Each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Claims

1. A kind of electric core, characterized by comprising the following steps:

the laminated structure comprises a negative pole piece and a positive pole piece which are alternately overlapped, and a solid electrolyte layer is arranged between the adjacent positive pole piece and the negative pole piece;

the packaging structure comprises a filling part and a penetrating part, wherein the filling part is arranged in a sheet gap of the lamination structure, the penetrating part is a part which extends from the filling part to penetrate into the interior of a sheet around the sheet gap, and the penetrating depth of the penetrating part is larger than or equal to 1 mu m.

2. The cell of claim 1, wherein the cell comprises a plurality of conductive traces,

The penetration depth of the penetration portion is greater than or equal to 1 μm and less than or equal to 300 μm, or the penetration depth of the penetration portion is greater than or equal to 10 μm and less than or equal to 300 μm, or the penetration depth of the penetration portion is greater than or equal to 50 μm and less than or equal to 300 μm, or the penetration depth of the penetration portion is greater than or equal to 100 μm and less than or equal to 300 μm, or the penetration depth of the penetration portion is greater than or equal to 150 μm and less than or equal to 300 μm, or the penetration depth of the penetration portion is greater than or equal to 200 μm and less than or equal to 250 μm, and/or

The area percentage of the electrode plate occupied by the penetrating part is less than or equal to 1 percent.

3. The cell of claim 1, wherein the cell comprises a plurality of conductive traces,

The packaging material of the packaging structure comprises insulating material, and/or

The encapsulating material of the encapsulating structure comprises a resin material with permeability capable of changing according to temperature, and/or

The packaging material of the packaging structure comprises a hot melt resin material and/or

The encapsulating material of the encapsulating structure includes a polymer containing one or more polar functional groups of ester groups, carboxyl groups, anhydride groups, amide groups, amino groups, hydroxyl groups, and epoxy groups.

4. The cell of claim 3, wherein the cell,

The encapsulating material further comprises auxiliary additives including one or more of a compatibilizer, a coupling agent, a surfactant, and an inorganic filler, and/or

The packaging material also comprises auxiliary additives, wherein the mass percentage of the auxiliary additives is 20% -60%.

5. The cell according to any one of claim 1 to 4, wherein,

The sheet layer gap comprises a dislocation gap generated by dislocation when the negative electrode sheet, the solid electrolyte layer and the positive electrode sheet are overlapped and/or a overhang gap corresponding to a overhang area formed by at least one side of the circumference of the negative electrode sheet exceeding the positive electrode sheet, and/or

The packaging structure further comprises a coating part, wherein the coating part is connected with the filling part and coats the peripheral side surface of the lamination structure.

6. A method of packaging a cell as claimed in any one of claims 1 to 5, comprising:

Stacking the positive electrode plate, the negative electrode plate and the solid electrolyte layer in the sequence of the positive electrode plate, the solid electrolyte layer, the negative electrode plate and the solid electrolyte layer to obtain a lamination structure, wherein a sheet gap is formed on the peripheral side surface of the lamination structure;

And arranging an encapsulation material in the sheet gap of the lamination structure to obtain the battery core with the encapsulation structure, wherein the encapsulation material can permeate into the sheet layer at the periphery of the sheet gap to form a permeation part.

7. The method of packaging of claim 6, wherein disposing packaging material into the sheet voids of the lamination stack comprises:

and setting packaging materials in the sheet gaps of the lamination structure by adopting a 3D printing method, a pouring method or a filling method.

8. The method of claim 6, wherein providing the encapsulation material into the sheet voids of the lamination structure to obtain an encapsulated lamination structure comprises:

Arranging a first permeable packaging material in a sheet gap of the laminated structure to obtain a first laminated structure with a first packaging layer, wherein the first packaging layer is provided with a penetration part penetrating into the sheet layer around the sheet gap and a first filling part positioned in the sheet gap, and the thickness of the first filling part is smaller than the depth of the sheet gap;

And arranging a second permeable packaging material in the sheet gap of the first lamination structure, and obtaining a second packaging layer outside the first packaging layer to obtain the packaging lamination structure, wherein the outer surface of the second packaging layer is level with the peripheral side surface of the lamination structure, or the second packaging layer protrudes out of the peripheral side surface of the lamination structure and forms a coating part for coating the peripheral side surface of the lamination structure, and the permeability of the second permeable packaging material is smaller than that of the first permeable packaging material.

9. The packaging method of claim 8, wherein the packaging method comprises the steps of,

The first and second permeable sealing materials are made of resin material with permeability capable of changing according to temperature, and/or

And setting packaging materials in the sheet gap area of the lamination structure by adopting a 3D printing method, a filling method or a filling method, or setting the packaging materials in the gap area of the lamination structure by adopting multi-head 3D printing equipment or a multi-head glue filling machine, wherein a first discharging head is used for outputting a first permeable packaging material, and a second discharging head is used for outputting a second permeable packaging material.

10. The method according to any one of claims 6 to 9, wherein the encapsulating material comprises an encapsulating material having a permeability which is positively dependent on temperature, and wherein the encapsulating material is arranged in the sheet voids of the laminate structure, comprises arranging the encapsulating material layer by layer in the sheet voids of the laminate structure, and wherein the heating temperature of the encapsulating material decreases from the inner layer to the outer layer.

11. The encapsulation method according to any one of claims 6 to 9, further comprising, while disposing an encapsulation material into the sheet voids of the lamination structure:

Acquiring permeation information capable of reflecting the permeation condition of the packaging material;

the penetration capacity of the encapsulation material is adjusted according to the penetration information.

12. The method of claim 11, wherein the infiltration information reflecting the infiltration of the first permeable encapsulation material comprises infrared imaging image information.

13. The method of packaging according to any one of claims 6 to 9, further comprising the step of subjecting the lamination stack provided with the encapsulating material to a heat press treatment after disposing the encapsulating material into the void region of the lamination stack.

14. The packaging method of claim 13, wherein the thermo-compression process is performed on the lamination structure provided with the packaging material, comprising:

placing the lamination structure with the packaging material on a heating plate with a first preset temperature for a first preset time, or

The lamination stack provided with the encapsulation material is placed on a heating plate at a first preset temperature and pressure and/or vibration is applied for a second preset time.

15. The packaging method of claim 14, wherein the packaging method comprises the steps of,

In the case of pressure application, the means for applying pressure include applying a constant pressure, or applying a gradient pressure, or

In the case of applying pressure, the pressure includes a constant pressure of 0.3 to 0.5MPa, or the pressure includes a gradient pressure in the range of 0.3 to 3MPa, or

In the case of vibration, a constant pressure or a gradient pressure is applied, or

In the case of applying vibrations, the vibrations include vibrations having a frequency of 10 to 50 Hz and an amplitude of less than or equal to 50 μm, or vibrations include gradient step-wise vibrations in a frequency range of 20 to 2000 Hz.

16. The packaging method according to any one of claims 6 to 9, wherein a 3D printing method is used to provide packaging material into the sheet void region of the lamination structure, to obtain a 3D printing temperature regulation packaging method, comprising:

Vertically arranging the lamination structure in a printing area of the 3D printing equipment in a mode that the side to be printed faces upwards;

the method comprises the steps of obtaining contour entity data of a side surface to be printed of a lamination structure, obtaining a contour three-dimensional model according to the contour entity data, slicing the contour three-dimensional model, planning a path and designing printing parameters to obtain printing information;

And the 3D printing equipment prints the packaging material on the side to be printed according to the printing information and the heating temperature of the packaging material, and finishes packaging printing of the side to be printed of the lamination structure, so that the lamination structure provided with the packaging material is obtained.

17. A system for packaging a battery cell, for implementing the method for packaging a battery cell according to any one of claims 6 to 16, comprising:

a fluid material precision coating device;

the conveying and positioning module is used for conveying the lamination structure completed with lamination to a working area of the fluid material precise coating equipment after overturning the lamination structure to be vertical;

The scanning module is used for scanning outline entity data of a side surface to be printed of the lamination structure arranged in the working area of the fluid material precision coating equipment;

The control unit is used for obtaining a contour three-dimensional model according to the contour entity data, slicing the contour three-dimensional model, planning a path and designing coating parameters to obtain coating information;

the fluid material precision coating equipment receives the coating information of the control unit, and sets the melted packaging material heated to the preset temperature on the side surface to be printed of the lamination structure in the working area according to the coating information, so that the packaging material can permeate into the inner part of the sheet layer around the gap of the sheet layer to form a permeation part.

18. The cell packaging system of claim 17, further comprising:

The hot pressing device comprises a heating plate and a pressing plate, wherein a heating groove is arranged on the heating plate, the groove cavity of the heating groove is consistent with the outer contour of the lamination structure provided with the packaging material, the pressing plate is movably arranged above the heating plate, the pressing plate can be buckled on the heating plate to press the lamination structure placed in the heating groove, and/or the heating plate is provided with a pressing plate which is fixedly connected with the heating plate, and the pressing plate is fixedly connected with the heating plate

The hot press device also comprises a vibration structure for applying vibration to the lamination structure arranged on the heating plate, or the vibration structure comprises a flexible vibration plate arranged in the heating groove of the heating plate or the heating plate is arranged on the flexible vibration plate, and/or

And the infrared scanning equipment is used for carrying out infrared imaging scanning monitoring on the gap of the sheet layer when the packaging material is arranged in the gap of the sheet layer of the lamination structure so as to acquire infrared imaging image information and reflect the penetration information of the penetration condition of the packaging material.

19. The system for packaging a battery cell of claim 17,

The coating information includes a coating path and coating parameters, and/or

The fluid material precision coating equipment comprises a 3D printing equipment or a glue filling machine, and/or

The fluid material precise coating equipment comprises 3D printing equipment, wherein the coating information obtained by the control unit comprises a printing path and printing information, the printing information comprises one or more of a circular track and/or a linear track, the line width is 80-120 mu m, the layer height is 5-20 mu m, the printing speed is 25-45 mm/s, the heating temperature is within the melting point range of the packaging material, and the temperature of a printing head is 1-50 ℃ higher than the heating temperature;

When the thermal melting type resin material as claimed in claim 21 or 22 is used as the packaging material, the heating temperature in the printed information is 60-100 ℃.

20. The system for packaging a battery cell of claim 18,

When the packaging system of the battery cell is used for realizing the packaging method of the battery cell comprising the claim 8, the heating temperature in the printed information comprises a first heating temperature and a second heating temperature, wherein the first heating temperature is higher than the second heating temperature;

When the thermal melting type resin material according to claim 21 or 22 is used as the packaging material, the first heating temperature is selected from 80 ℃ to 100 ℃, and the second heating temperature is selected from 60 ℃ to 100 ℃.

21. A hot-melt type resin material characterized by being an encapsulating material of the encapsulating structure of the cell according to any one of claims 1 to 5, or an encapsulating material in the encapsulating method of the cell according to any one of claims 6 to 16, or an encapsulating material for use as a fluid material precision coating of the encapsulating system of the cell according to any one of claims 17 to 20;

The hot melt resin material comprises, by mass, 40-80 parts of matrix resin, 5-10 parts of a compatibilizer, 0-3 parts of a coupling agent and 0-60 parts of an inorganic filler, wherein the matrix resin comprises a polymer containing one or more polar functional groups of ester groups, carboxyl groups, acid anhydride groups, amide groups, amino groups, hydroxyl groups and epoxy groups.

22. The hot-melt resin material according to claim 21, wherein,

The hot-melt resin material has at least one of a melting point of 60-100 ℃, a melt index of 200-400 g/10 min, a melt viscosity of 2000-12000 mPa.s, a contact angle with the surface of a battery pole piece of less than or equal to 60 degrees, and/or

The matrix resin comprises one or more of ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polyethylene terephthalate and ethylene-acrylic acid copolymer, and/or

The compatibilizer and/or coupling agent is selected from polymers containing one or more polar functional groups of ester group, carboxyl group, anhydride group, amide group, amino group, hydroxyl group and epoxy group, and/or

The compatibilizer comprises one or more of maleic anhydride grafted polyolefin, epoxy modified polyolefin, polypropylene grafted polystyrene, and/or

The coupling agent comprises a silane coupling agent, and/or

The coupling agent comprises one or more of gamma-aminopropyl triethoxysilane, vinyl trimethoxy silane and vinyl triethoxysilane, and/or

The coupling agent comprises titanate coupling agent, and/or

The coupling agent comprises isopropyl triisostearate titanate and/or isopropyl dioleate acyloxy titanate, and/or

The inorganic filler comprises one or more of barium sulfate, titanium pigment, talcum powder, bentonite, quartz sand, aluminum oxide, calcium carbonate, glass powder and zinc oxide, and/or

Alumina nano particles with the particle size of 20-50 nm of inorganic filler.

23. A solid-state battery characterized by comprising a cell according to any one of claims 1 to 5, a cell obtained by encapsulation using the encapsulation method of a cell according to any one of claims 6 to 16, or a cell obtained by encapsulation using the encapsulation system of a cell according to any one of claims 17 to 20.