CN218005111U

CN218005111U - Battery and electronic equipment

Info

Publication number: CN218005111U
Application number: CN202222119394.5U
Authority: CN
Inventors: 胡贤飞; 王楠楠; 彭冲; 李俊义
Original assignee: Zhuhai Cosmx Battery Co Ltd
Current assignee: Zhuhai Cosmx Battery Co Ltd
Priority date: 2022-08-12
Filing date: 2022-08-12
Publication date: 2022-12-09
Anticipated expiration: 2032-08-12

Abstract

The invention provides a battery and electronic equipment, wherein the battery comprises a battery cell and a shell, the shell comprises a shell for wrapping the battery cell and a sealing edge for sealing the shell, and the sealing edge is positioned on one side of the shell in the width direction; the lug is electrically connected with the battery cell and extends to the outside of the shell from the sealed edge; the projection of the sealed edge on the end face of the pole lug extending out of the shell does not exceed the projection of the pole lug extending out of the end face of the shell. The shell comprises the shell and the sealing edge, and the sealing edge is positioned on one side of the shell in the width direction.

Description

Battery and electronic equipment

Technical Field

The invention relates to the technical field of lithium ion batteries, in particular to a battery and electronic equipment.

Background

The lithium ion battery has the advantages of high energy density, long cycle life, small self-discharge, no memory effect and the like, and has received wide attention and application since commercialization. With the rapid development of new energy industries, the rapid development of lithium ion batteries is also driven. In addition to the higher requirements for the safety performance of the lithium ion battery, the market also has higher and higher requirements for the energy density of the lithium ion battery, which promotes the development of the lithium ion battery towards high volume and high mass density.

At present, most consumer lithium ion batteries adopt an aluminum-plastic film as a battery shell, and compared with hard shell shells such as stainless steel, the aluminum-plastic film shell has the following advantages:

(1) The lithium ion battery adopts the aluminum-plastic film as the shell, and when thermal management is out of control or puncture occurs, the aluminum-plastic film shell can provide a buffer space for the battery cell, and the battery cell generates bulging deformation, finally only generates heat or smoke, but does not generate combustion and explosion;

(2) The battery adopting the aluminum plastic film as the shell has the advantages that the weight is 40% lighter than that of a steel shell battery with the same weight, and the energy density is higher;

(3) The electrochemical performance is good, the service life is long, the internal resistance of the battery adopting the aluminum plastic film as the shell is small, the self-consumption of the battery can be greatly reduced, and the cycle life of the battery can be prolonged.

Although there are many advantages to adopt the aluminum-plastic film as the battery case, when the battery is packaged, the aluminum-plastic film needs to be punched to form an upper case and a lower case, the upper case and the lower case are spliced to form a case, the top seal formed after the upper case and the lower case are spliced is horizontally packaged, and two sides of the case are side sealed, that is, side sealing edges along the two sides of the case are formed on the case, and the side sealing edges can increase the volume of the battery and lose the energy density; in addition, the aluminum-plastic film is generally formed by punching a pit, so that the periphery of the aluminum-plastic film extends to form a pit-shaped structure with a certain depth, but the thickness of the formed part is not uniform, the corner of the shell is easy to break, and great potential safety hazards are brought.

Disclosure of Invention

The invention aims to solve the problem that the side sealing edge of the existing battery shell influences the energy density of a battery.

In order to solve the above problems, a first aspect of the present invention provides a battery, including a battery core and a casing;

the shell comprises a shell wrapping the battery cell and an edge sealing for sealing the shell, and the edge sealing is positioned on one side of the shell in the width direction;

the lug is electrically connected with the battery cell and extends to the outside of the shell from the sealed edge;

the projection of the seal edge on the end face of the lug extending out of the shell does not exceed the projection of the lug extending out of the end face of the shell.

Further, the width of the seal edge does not exceed the width of the shell.

Furthermore, the end face of the tab extending out of the shell is a top end face, the shell further has a bottom end face and a side face located between the top end face and the bottom end face, and the bottom end face and the side face enclose to form a containing cavity for containing the battery core.

Further, the top end face, the bottom end face and the side face are of an integral structure, and/or the top end face, the bottom end face and the side face are the same in thickness.

Further, the thickness of the corner of the outer shell is the same as the thickness of the outer shell, and the corner of the outer shell is the intersection area of the top end surface of the outer shell and the side surface of the outer shell, and the intersection area of the bottom end surface of the outer shell and the side surface of the outer shell.

Further, the shell comprises an impermeable layer and a reinforcing layer which are sequentially stacked, wherein the impermeable layer is arranged inside the shell.

Furthermore, the anti-seepage layer is a plastic material layer, and the reinforcing layer is a metal material layer attached to the outer surface of the anti-seepage layer.

Further, the shell also comprises an insulating protection layer, and the insulating protection layer is arranged on the outer surface of the reinforcing layer.

Further, a tab glue is arranged on the tab, and the tab glue is connected with the impermeable layer in a sealing mode.

A second aspect of the invention provides an electronic device comprising at least one battery according to any of the first aspects.

According to the battery and the electronic equipment provided by the invention, the shell comprises the shell and the seal edge, the seal edge is positioned on one side of the width direction of the shell, compared with the seal edge positioned on one side of the width direction of the shell and the two sides of the length direction of the shell in the prior art, the space volume occupied by the seal edge for the battery can be reduced, the installation space occupied by the battery is saved, the energy density of the battery is improved, the projection of the seal edge on the end face of the lug extending out of the shell is not more than that of the lug extending out of the end face of the shell, and the energy density of the battery can be further improved.

Drawings

Fig. 1 is a schematic front view of a battery according to the novel embodiment of the present invention;

fig. 2 is a schematic top view of a battery according to the novel embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a housing according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a process for manufacturing a battery according to an embodiment of the invention.

Description of reference numerals:

100-a housing; 101-a housing; 102-edge sealing; 110-a first tab; 120-a second tab; 130-an airbag; 140-corner;

1011-barrier layer; 1012-reinforcing layer; 1013-insulating protective layer.

Detailed Description

The technical scheme of the invention is clearly and thoroughly described in the following with reference to the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. Further, in the description of the present invention, "at least one" means one or more unless specifically limited otherwise.

In the description of the present specification, the term "on the basis of the above-described embodiments" means that a specific feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one preferred embodiment or preferred example of the present invention. Throughout this specification, the schematic representations of the terms used above do not necessarily refer to the same implementation or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

As shown in fig. 1 to 2, the present embodiment provides a battery, which includes a battery core, a casing 100, and tabs;

the casing 100 includes a casing 101 for wrapping the battery cell and a sealing edge 102 for sealing the casing 101, where the sealing edge 102 is located on one side of the casing 101 in the width direction (i.e., the y-axis direction in fig. 1);

the tab is electrically connected with the battery cell and extends from the sealed edge 102 to the outside of the shell 100;

the projection of the seal edge 102 on the end surface of the tab extending out of the housing 101 does not exceed the projection of the tab extending out of the end surface of the housing 101, that is, the width of the seal edge 102 does not exceed the width of the housing 101.

In this embodiment, the casing 100 includes shell 101 and banding 102, banding 102 is located one side of the width direction of shell 101, with banding 102 among the prior art not only be located one side of the width direction of shell 101, still be located the length direction's of shell 101 both sides and compare, can reduce the space volume that banding 102 occupy the battery, save the installation space that the battery occupied, promote the energy density of battery, and banding 102 is no longer than the terminal surface that the utmost point ear extends shell 101 at the projection that utmost point ear extends the terminal surface of shell 101, can further promote the energy density of battery.

The shell 101 is provided with a top end face, a bottom end face and a side face located between the top end face and the bottom end face, the end face, extending out of the shell, of each lug is of an integrated structure, the top end face, the bottom end face and the side face are the same in thickness, the bottom end face and the side face are enclosed to form a cavity with an opening, the shell is of an open-ended structure before sealing, the top ends of the side faces (namely the sides of the side faces, far away from the bottom end face) are in butt joint, the top end face and the sealing edge 102 are formed after bending and sealing, the top end face and the sealing edge 102 are integrally formed, the sealing edge 102 is located on the side, far away from the side face, the top end face, the bottom end face and the side face are enclosed to form a closed accommodating cavity, and the battery cell is accommodated in the accommodating cavity. Therefore, the shell 101 is of an integral structure, the corners of the shell 101 are integrally formed, pit punching is not needed, the corners of the shell 101 are uniform in thickness, and potential safety hazards of battery leakage caused by the fact that the corners of the shell 101 are prone to cracking are reduced.

The shape of the casing 101 is identical to that of the battery cell, so that the shape of the accommodating cavity for accommodating the battery cell in the casing 101 is identical to that of the battery cell, which is beneficial to improving the proportion of the battery cell and improving the capacity of the battery.

The thickness of the corner 140 of the casing 101 is the same as the thickness of the casing 101, that is, the thickness of the corner 140 of the casing 101 is the same as the thickness of each surface (including the top end surface, the bottom end surface and the side surface) of the casing 101, so that the thickness of each position of the casing 101 can be uniform, compared with an aluminum plastic film casing, the risk of corner 140 corner crack of the casing 101 can be greatly reduced, and the safety of the battery can be improved, and the thickness of the corner 140 of the casing 101 is the same as the thickness of each surface of the casing 101, which is beneficial to improving the overall strength of the casing 101 and improving the protection performance of the casing 101.

Here, the corner 140 of the housing 101 refers to an area where the top end surface and the side surface of the housing 101 meet, and an area where the bottom end surface and the side surface of the housing 101 meet.

Referring to fig. 3, the housing 101 is integrally formed, and the housing 101 includes a barrier layer 1011 and a reinforcing layer 1012 which are sequentially stacked, and the barrier layer 1011 is disposed inside the housing 101. Therefore, the outer shell 101 comprises the impermeable layer 1011 and the reinforcing layer 1012, the reinforcing layer 1012 can improve the structural strength of the outer shell 101, improve the overall strength of the outer shell 101, and reduce the risk that the outer shell 101 is low in strength and is easily pierced by foreign matters

The barrier layer 1011 is located the inboard of shell 101, and barrier layer 1011 has better barrier property, and can wear-resisting, anti chemical corrosion, and has high insulating nature, better heat resistance, ageing resistance, can prevent revealing of electrolyte, guarantees the security of battery. On the basis of the above embodiment, the material of the anti-seepage layer 1011 is plastic, the integrally formed housing 101 can be obtained by injection molding the anti-seepage layer 1011 made of plastic, and the plastic material can be polyamide-66 (nylon 66), polypropylene Plastic (PP), polyethylene Plastic (PE), or the like. Preferably, the material of the impermeable layer 1011 is Polypropylene Plastic (PP), and the PP is a thermoplastic material, which is resistant to electrolyte, suitable in packaging temperature and not easy to deform, and can enable the side surface of the housing 101 to be butted and then sealed by hot melting to form the top end surface and the sealing edge 102.

Since the anti-seepage layer 1011 is integrally formed by injection molding, a person skilled in the art can increase or reduce the thickness of the anti-seepage layer 1011 according to the size and the dimension of the battery to adjust the thickness of the outer shell 101, and compared with the case adopting an aluminum plastic film as the shell, the thickness of the outer shell 101 in the embodiment can be adjusted to better match with batteries of different sizes and dimensions. Specifically, barrier 1011's thickness can set up to 20um to 50um, for example, barrier 1011's thickness can set up to 20um, 40um or 50um, when guaranteeing that can be better separation electrolyte, control thickness to reduce the space volume of shell 101, reduce the volume and the weight of battery, increase the energy density of battery, improve the performance of battery.

The reinforcing layer 1012 is positioned on the outer surface of the impermeable layer 1011, and the reinforcing layer 1012 is arranged on the outer surface of the impermeable layer 1011, so that not only can sharp objects be prevented from puncturing the impermeable layer 1011, but also the whole housing 101 can have better structural strength and is not easy to bulge and deform. In addition to the above embodiments, the material of the reinforcing layer 1012 is a metal material layer, and the metal in the metal material layer can be selected from aluminum alloy, nickel alloy, chromium alloy, copper alloy, stainless steel, and the like. The reinforcement layer 1012 may be attached to the outer surface of the reinforcement layer 1012 by electroless plating, evaporation, thermal compounding, vacuum sputtering, laser pulsing, vacuum deposition, ion plating, and the like.

Those skilled in the art can set the thickness of the reinforcing layer 1012 according to actual conditions, specifically, the thickness of the reinforcing layer 1012 can be set to 5um to 50um, for example, the thickness of the reinforcing layer 1012 can be set to 5um, 15um or 35um, and while ensuring that the housing 101 has better structural strength, the thickness is controlled to reduce the spatial volume of the housing 101, reduce the volume and weight of the battery, increase the energy density of the battery, and improve the performance of the battery.

The housing 101 further comprises an insulating protection layer 1013, the insulating protection layer 1013 is disposed on an outer surface of the reinforcement layer 1012, that is, the housing 101 is formed by the stacked impermeable layer 1011, the reinforcement layer 1012 and the insulating protection layer 1013, the impermeable layer 1011 and the insulating protection layer 1013 are respectively located on two opposite side surfaces of the reinforcement layer 1012, and the insulating protection layer 1013 can perform insulating protection on the battery cell, so as to prevent the battery from being in contact with external electronic components to cause short circuit, which is beneficial to improving the insulation performance and the use safety of the battery. In addition to the above embodiments, the insulating protection layer 1013 is made of an insulating material, and the insulating material may be made of an insulating material such as nylon or polyurethane.

Those skilled in the art can set the thickness of the insulating protection layer 1013, specifically, the thickness of the insulating protection layer 1013 may be set to 5um to 20um, for example, the thickness of the insulating protection layer 1013 may be set to 5um, 10um or 18um, and while ensuring that the housing 101 has better insulation, the thickness is controlled to reduce the spatial volume of the housing 101, reduce the volume and weight of the battery, increase the energy density of the battery, and improve the performance of the battery.

In this embodiment, the sealing edge 102 and the outer shell 101 are integrally formed, so that the material of the sealing edge 102 is the same as that of the outer shell 101, that is, the sealing edge 102 is also formed by an impermeable layer, a reinforcing layer and an insulating protective layer which are stacked, and the impermeable layer and the insulating protective layer are respectively located on two opposite side surfaces of the reinforcing layer.

The seal 102 comprises a top edge to be connected to the tab and side edges to be connected to the lateral faces of the casing 101, the top and side edges of the seal 102 being rounded excessively, thus avoiding the two corners at the top of the seal 102 being relatively sharp.

The battery further includes a first tab 110 and a second tab 120, wherein the polarities of the first tab 110 and the second tab 120 are opposite, specifically, the first tab 110 may be a positive tab, and may also be a negative tab, and correspondingly, the second tab 120 may also be a negative tab, and may also be a positive tab. The first tab 110 and the second tab 120 mainly function to guide the current collected on the battery cell outward.

The first tab 110 and the second tab 120 may each have one end connected to the battery cell, and the other end extending out of the casing 101 and located outside the casing 101, specifically, the first tab 110 and the second tab 120 may extend from the same side of the casing 101, that is, the first tab 110 and the second tab 120 may be located at the same side of the battery, and the first tab 110 and the second tab 120 may also extend from different sides of the casing 101, that is, the first tab 110 and the second tab 120 may be located at different sides of the battery, but in order to reduce the space volume of the battery, improve the energy density of the battery, shorten the migration distance of active lithium ions, and reduce the resistance of the battery cell, based on the above embodiment, the first tab 110 and the second tab 120 are located at the same side of the casing 101, specifically, the first tab 110 and the second tab 120 are both connected to the top end surface of the battery cell, that is, the top end surface of the battery cell is a side surface of the cell close to the top end surface of the casing 101, and the first tab 110 and the second tab 120 penetrate out of the casing 101 and are located outside the casing 101.

The first tab 110 and the second tab 120 are both provided with tab glue, and the tab glue is hermetically connected with the impermeable layer of the shell 101 so as to seal the gap between the shell and the tab and ensure the sealing performance of the battery.

The tab glue is insulating glue, and the tab glue is fused with the impermeable layer 1011 of the shell 101 through heat sealing, so that the tab glue is hermetically connected with the shell 101.

To illustrate the improvement of the overall strength of the battery by the housing 101, this embodiment shows a control experiment, which includes three experimental groups and a control group, wherein the control group and the experimental group have the same size and other variables except the setting of the housing 101, and the control group and the experimental group are specifically set as follows:

experimental group 1: the housing 101 is formed by a barrier layer 1011, a reinforcing layer 1012 and an insulating protection layer 1013 which are stacked, the barrier layer 1011 and the insulating protection layer 1013 are respectively positioned on two opposite side surfaces of the reinforcing layer 1012, the barrier layer 1011 is a PP layer, the reinforcing layer 1012 is an aluminum alloy layer, and the insulating protection layer 1013 is a nylon layer;

experimental group 2: the casing 101 is formed by a seepage-proof layer 1011, a reinforcing layer 1012 and an insulating protection layer 1013 which are arranged in a laminated manner, wherein the seepage-proof layer 1011 and the insulating protection layer 1013 are respectively arranged on two opposite side surfaces of the reinforcing layer 1012, the seepage-proof layer 1011 is a PP layer, the reinforcing layer 1012 is a nickel alloy layer, and the insulating protection layer 1013 is a nylon layer;

experimental group 3: the housing 101 is formed by a barrier layer 1011, a reinforcing layer 1012 and an insulating protection layer 1013 which are stacked, the barrier layer 1011 and the insulating protection layer 1013 are respectively positioned on two opposite side surfaces of the reinforcing layer 1012, the barrier layer 1011 is a PP layer, the reinforcing layer 1012 is a chromium alloy layer, and the insulating protection layer 1013 is a nylon layer;

control group: the case 101 is formed of only an aluminum plastic film.

The batteries prepared in the above groups were subjected to heat-seal strength and tensile strength tests to obtain test results as shown in Table 1

TABLE 1 Strength profiles of the experimental and control groups

Categories	Heat seal Strength/MPa	Tensile strength/MPa
			Experimental group 1	2.27	68
Experimental group 2	2.3	80
			Experimental group 3	2.5	86
Control group	2.2	65

As can be seen from table 1, in the present embodiment, by forming the case 101 by using the barrier layer 1011, the reinforcement layer 1012, and the insulating protection layer 1013 which are stacked, the heat seal strength and the tensile strength of the entire battery can be improved, which is advantageous for improving the entire strength of the battery.

A second aspect of the present invention provides an electronic device comprising a battery as shown in the first aspect. For example, the electronic device may include the battery shown in the first aspect, and the electronic device may also include a plurality of batteries shown in the first aspect, and if the electronic device includes a plurality of batteries shown in the first aspect, the battery housings are connected in series and/or in parallel to each other to form a battery module and are used in the electronic device.

The electronic equipment of this embodiment includes the battery, this battery includes casing and electric core, casing 100 includes shell 101 and banding 102, banding 102 is located one side of the width direction of shell 101, banding 102 is located the both sides of shell 101 length direction among the prior art and compares, can reduce the spatial volume that the banding took the battery, save the installation space that the battery took, promote the energy density of battery, and banding 102 does not exceed the terminal surface that the utmost point ear extended shell 101 at the projection that utmost point ear extended shell 101's terminal surface, can further promote the energy density of battery.

Fig. 4 is a schematic diagram of a process for manufacturing a battery according to the present embodiment, and fig. 4 is a schematic diagram of a battery with a sealed edge 102 not shown, where fig. 4A is a schematic diagram of a battery structure before an airbag is cut off, and fig. 4B is a schematic diagram of a battery structure after an airbag is cut off. In a specific embodiment, as shown in fig. 4, the battery is manufactured as follows:

firstly, adding a negative electrode active substance, a conductive agent, a binder and a dispersing agent into a stirring tank according to a certain mass ratio for mixing, adding deionized water for dispersing to prepare negative electrode active slurry with appropriate solid content (for example, the negative electrode active slurry with the solid content of 40-45%), coating the negative electrode active slurry on a negative electrode current collector through coating equipment, drying at the temperature of 100 ℃, rolling, cutting, carrying out laser cleaning to form a polar lug groove, and welding a nickel polar lug to obtain a negative electrode piece.

And then, adding the positive electrode active substance, the conductive agent and the binder into a stirring tank according to a certain mass ratio for mixing (for example, mixing lithium cobaltate, the conductive agent and polyvinylidene fluoride according to the mass ratio of 97: 1.5), adding N-methylpyrrolidone (NMP) to adjust into positive electrode active slurry after mixing is finished, coating the positive electrode active substance on the surface of a positive electrode current collector through coating equipment, drying at 120 ℃, cleaning by using a scraper after drying, washing out the welding position of a positive electrode lug, compacting by using a roller press, and welding an aluminum lug to obtain the positive electrode piece.

After preparing the pole pieces, sequentially stacking the positive pole piece, the diaphragm and the negative pole piece together to be wound to form a roll core, using an integrally formed PP packaging bag with an opening structure at the top as an impermeable layer 1011, placing the roll core in the PP packaging bag, packaging the top of the PP packaging bag, arranging one end of each of the positive pole lug 110 and the negative pole lug 120 outside the PP packaging bag, arranging an air bag 130 integrally formed with the PP packaging bag between the positive pole lug 110 and the negative pole lug 120, plating a layer of metal alloy (such as nickel alloy or chromium alloy) on the outer surface of the PP packaging bag as a reinforcing layer 1012, arranging a layer of nylon on the surface of the metal alloy layer as an insulating protection layer 1013, performing processes of secondary packaging and the like after injecting, aging, forming and cutting off the air bag 130 to obtain the battery, and finally testing the electrochemical performance of the battery.

Among other things, bladder 130 is suitable for storing gases generated during aging and formation, and requires cutting after formation, which are not exhibited in the final finished battery structure.

In addition, the structure, function and operation principle of the housing are described in detail in the first embodiment, and are not described herein again.

Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.

Claims

1. The battery is characterized by comprising a battery core, a tab and a shell;

the shell comprises a shell wrapping the battery cell and a sealing edge sealing the shell, and the sealing edge is positioned on one side of the shell in the width direction;

2. The battery of claim 1, wherein the seal has a width that does not exceed a width of the housing.

3. The battery of claim 1, wherein the end surface of the tab extending out of the housing is a top end surface, the housing further has a bottom end surface and a side surface between the top end surface and the bottom end surface, and the bottom end surface and the side surface enclose a containing cavity for containing the battery cell.

4. The battery of claim 3, wherein the top end face, the bottom end face, and the side face are of unitary construction and/or the top end face, the bottom end face, and the side face are the same thickness.

5. The battery of claim 3, wherein the thickness of the corner of the housing is the same as the thickness of the housing, and the corner of the housing is an area where the top end surface of the housing meets the side surface of the housing and an area where the bottom end surface of the housing meets the side surface of the housing.

6. The cell defined in claim 1, wherein the outer casing includes a barrier layer and a reinforcing layer disposed in this order, the barrier layer being disposed inside the outer casing.

7. The cell defined in claim 6, wherein the barrier layer is a layer of plastic material and the reinforcement layer is a layer of metal material attached to an outer surface of the barrier layer.

8. The battery of claim 6, wherein the housing further comprises an insulating protective layer disposed on an outer surface of the reinforcement layer.

9. The battery of claim 6, wherein the tab is provided with tab glue, and the tab glue and the impermeable layer are hermetically connected.

10. An electronic device comprising at least one battery according to any one of claims 1 to 9.