CN218472239U - Turnover sheet component, battery cover plate assembly and battery - Google Patents

Abstract

The utility model discloses a reversing sheet assembly, a battery cover assembly and a battery. The reversing sheet assembly comprises: a reversing sheet; a base, the base is sealed and connected with the reversing sheet to form an accommodation space; an elastic member, the elastic The elastic member is arranged in the accommodating space and abuts between the turning piece and the base, and the elastic member is adapted to be deformed at a predetermined temperature so that the turning piece moves to the side away from the base Flip. The heat generated when the battery is overcharged is used to heat the elastic member in the storage space, so that the elastic force generated by the elastic member pushes the flip piece upward, thereby conducting the first pole and the second pole, and interrupting the charging by triggering the fuse .

Description

Flip sheet assembly, battery cover plate assembly and battery

technical field

The utility model relates to the technical field of a cover plate assembly, in particular to a reversing sheet assembly, a cover plate assembly and a battery.

Background technique

Overcharging of lithium-ion batteries may cause bursting, fire, explosion and other hazards. In this regard, the general solution is to install explosion-proof valves and other safety devices on the battery, such as current short-circuit devices. The explosion-proof valve can be opened when the internal pressure of the battery is too high to release the battery pressure; other safety devices such as the current short circuit device can use the flip plate to realize overcharge safety protection. When the battery is turned over, the reversing piece will be turned upwards, thereby short-circuiting the battery, and then stopping charging the battery. Therefore, the inversion sheet needs high battery internal pressure caused by overcharging and gas production inside the battery to cause inversion to function.

However, the amount of gas produced inside the battery changes with the degree of overcharge and temperature of the battery. The higher the degree of overcharge, the higher the temperature, the greater the amount of gas produced, and the greater the internal pressure of the battery. When the internal pressure of the battery reaches the pressure that can activate the safety device, the internal temperature of the battery may already be very high, resulting in the inability to prevent further reaction of the internal materials of the battery at high temperature and the subsequent thermal runaway of the battery and other safety problems.

Utility model content

The utility model aims at at least solving one of the technical problems existing in the prior art. For this reason, the utility model proposes a reversing piece assembly, the first reversing piece can be turned over under the action of the elastic member, so that the first pole and the second pole can be electrically connected, so that when it is in an overcharged state cause the battery to terminate charging.

The utility model also provides a battery cover plate assembly.

The utility model further proposes a battery.

According to the embodiment of the first aspect of the utility model, the flipping piece assembly includes: a flipping piece; a base, the base is sealed and connected with the turning piece to form an accommodation space; an elastic member, the elastic piece is arranged in the accommodation space And abutted between the turning piece and the base, the elastic member is adapted to be deformed at a predetermined temperature, so that the turning piece turns over to a side away from the base.

According to the turning plate assembly of the embodiment of the present invention, the heat generated when the battery is overcharged is used to heat the elastic member in the accommodation space, so that the elastic force generated by the elastic member pushes the turning plate to turn upwards, thereby short-circuiting the battery. In this process, the flipper assembly does not need to rely on the battery internal pressure generated by battery overcharging to operate, but by sensing the heat generated by battery overcharging, the flipper flips under the action of the elastic force of the elastic member in the accommodating space. When it is in a relatively low overcharge state, the battery can be terminated to charge, avoiding further reaction of the internal materials of the battery at high temperature and subsequent safety problems such as battery thermal runaway, which effectively improves the charging safety.

According to some embodiments of the present invention, the elastic member includes: a hot-melt part and an elastic part, the hot-melt part wraps outside the elastic part, and the hot-melt part is suitable for melting at a predetermined temperature.

According to some embodiments of the present utility model, the maximum distance between the opposing surfaces of the base and the turning piece is h, and h satisfies the relation: 1mm≤h≤10mm.

According to some embodiments of the present utility model, a first abutment post is provided on a side of the turning piece away from the base.

According to some embodiments of the present utility model, the base is a heat conducting base.

The battery cover assembly according to the second aspect of the present invention includes: a first pole, a second pole and the flipper assembly, and the polarity of the second pole is opposite to that of the first pole , the flipping piece is electrically connected to the first pole, and is suitable for being electrically connected to the second pole at a predetermined temperature.

According to some embodiments of the present invention, the battery cover assembly further includes: an electrical connector, the electrical connector is disposed at one end of the second pole and is electrically connected to the second pole, so The electrical connector is electrically connected to the flipping piece at a predetermined temperature.

According to some embodiments of the present utility model, a second abutment column is formed on a side of the electrical connector facing the turning piece.

According to some embodiments of the present invention, the battery cover plate assembly further includes: a cover plate and an insulating plate, the insulating plate is arranged on one side of the cover plate, and the first pole is arranged on the cover The plate is electrically connected to the cover plate, the electrical connector is arranged on the cover plate and electrically connected to the cover plate, and the second pole is arranged on the insulating plate.

The battery according to the embodiment of the third aspect of the present invention includes: a casing, a battery cell and the battery cover assembly, the casing has an accommodating cavity and an opening communicating with the accommodating cavity, and the cell is arranged in the In the accommodating cavity, the battery cover plate assembly is set on the opening.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present utility model will become apparent and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is a schematic structural view of a battery cover assembly according to an embodiment of the present invention;

Fig. 2 is a partial schematic diagram A in Fig. 1;

Fig. 3 is a schematic structural diagram of an elastic member according to an embodiment of the present invention.

Reference signs:

100. Battery cover assembly;

10. Turning piece assembly; 11. Base; 12. Turning piece; 121. First abutment column; 13. Elastic member; 131. Hot-melt part; 132. Elastic part; 14. Accommodating space;

20. First pole; 30. Second pole; 40. Electrical connector; 41. Second abutting pole; 50. Cover plate; 60. Insulation plate.

Detailed ways

Embodiments of the utility model are described in detail below, and the embodiments described with reference to the accompanying drawings are exemplary, and embodiments of the utility model are described in detail below.

Referring to Fig. 1-Fig. 3, the flipper assembly 10 according to the embodiment of the present invention is described below. The utility model proposes a battery cover assembly 100 having the above-mentioned flipper assembly 10, and the utility model further proposes A battery with the battery cover assembly 100 described above.

As shown in FIG. 1 and FIG. 3 , the flipper assembly 10 of the embodiment of the present invention includes: a flipper 12, a base 11 and an elastic member 13, and the base 11 is sealed with the flipper 12 to form an accommodation space 14, that is, the The flipper assembly 10 can act when the battery is overcharged, such as by electrically connecting the first pole 20 and the second pole 30 to form a short circuit in an external circuit, triggering a fuse to interrupt charging. Specifically, the turning piece assembly 10 includes a turning piece 12 and a base 11, and the base 11 is sealingly engaged with the turning piece 12 to form an accommodating space 14. The overturning piece 12 can be overturned towards the side of the accommodation space 14 (ie upward in the figure) when the side away from the base 11 receives a predetermined pressure, so as to electrically connect the first pole 20 and the second pole 30 .

Wherein, the predetermined pressure can be generated by the elastic member 13. The elastic member 13 is arranged in the accommodating space 14 and abuts between the turning piece 12 and the base 11. The elastic piece 13 is suitable for deformation at a predetermined temperature, so that the turning piece 12 Flip to the side away from the base 11. That is, the heat generated when the battery is overcharged causes the elastic member 13 to deform, thereby causing the flipping plate 12 to flip over, thereby making the first pole 20 and the second pole 30 electrically conductive, causing the battery to form a short circuit in the external circuit, and then triggering the fuse Interrupting charging can make the battery stop working in a lower overcharge state, which can better improve the safety of battery overcharge.

In addition, in the preferred embodiment shown in the figure, the reversing piece 12 can be formed as a revolving body structure. Therefore, the reversing in the present invention mainly refers to the deformation or displacement of the reversing piece 12 relative to its initial state, so as to trigger related control. For example, the turnover piece 12 can be set to be elastically deformable in directions away from the base 11, so that it can be elastically deformed into the accommodating space 14 in the initial state, and can be elastically deformed away from the accommodating space 14 after the compression spring recovers. The orientation of the receiving space 14 is convex (turned over).

Continuing to refer to Fig. 2, the turning piece 12 can be formed with a concave cavity on the side facing the base 11 and has a profile similar to the base 11, and the base 11 is covered and connected to the opening of the concave cavity, thus in the concave cavity A receiving space 14 is formed in the cavity. With such an arrangement, the sealing engagement between the base 11 and the turning piece 12 can be easily realized and the accommodation space 14 suitable for accommodating the elastic member 13 can be formed. Wherein, the base 11 can be connected to the opening of the concave cavity of the turning piece 12 by means such as welding, riveting, mechanical fit or glue.

Thus, the heat generated when the battery is overcharged is used to heat the elastic member 13 in the accommodating space 14, so that the elastic force generated by the elastic member 13 pushes the turning piece 12 to turn upwards, thereby conducting the first pole 20 and the second pole. Column 30, charging is interrupted by tripping the fuse. In this process, the reversing sheet assembly 10 does not need to rely on the battery internal pressure generated by the battery overcharge to operate, but senses the heat generated by the battery overcharging, and under the elastic force of the elastic member 13 in the accommodating space 14, the reversing sheet 12 flips, the battery can be terminated when it is in a low overcharge state, avoiding further reaction of the internal materials of the battery at high temperature and subsequent safety problems such as battery thermal runaway, which effectively improves the charging safety.

Referring to FIG. 3 , the elastic member 13 includes: a hot-melt portion 131 and an elastic portion 132 , the hot-melt portion 131 is wrapped around the elastic portion 132 , and the hot-melt portion 131 is suitable for melting at a predetermined temperature. Wherein, the elastic member 13 is a low-melting-point plastic and a compression spring sealed therein, and the melting point of the low-melting-point plastic is 50-100° C., for example, the low-melting-point plastic is polycaprolactone plastic (PCL plastic) or ethylene-vinyl acetate copolymer plastic One or more of materials such as (EVA plastic), preferably PCL plastic. In this way, the lower the melting point of the low-melting point plastic, the earlier it can be melted, so that the short circuit between the first pole 20 and the second pole 30 is earlier, which reduces the degree of overcharging and improves the safety of battery overcharging.

Wherein, the bottom and the top of the compression spring are respectively in contact with the upper surface of the base 11 and the lower surface of the turning plate 12. There is no special requirement for the compression spring. When the low melting point plastic melts and loses the binding force to the compression spring, the compression spring can stretch normally. And push the turning piece 12 to turn over and get final product.

Referring to FIG. 2 , the maximum distance between the opposing surfaces of the base 11 and the turning piece 12 is h, and h satisfies the relation: 1mm≤h≤10mm. Due to the limited layout space of the power battery, the flipper assembly 10 of the present utility model should not occupy a large space, so the distance between the upper surface of the base 11 and the lower surface of the flipper 12 should be as small as possible. In a certain space, the smaller the elastic member 13 is, the smaller the extension length will be, which will affect the turning over of the turning piece 12. In this way, the distance between the upper surface of the base 11 and the lower surface of the turning piece 12 cannot be too small. For example, in the preferred embodiment shown in the drawings, the distance between the lower surface of the base 11 and the upper surface of the turnover piece 12 changes with the change of their respective surface contours, and the distance between the two is the largest at the bottommost position of the accommodating space 14, It can be set to 3mm-7mm.

For this reason, the maximum distance between the surfaces of the base 11 and the turnover piece 12 facing each other can be set to 1mm-10mm.

Wherein, as shown in FIG. 2 , a first abutting column 121 is provided on a side of the turning piece 12 away from the base 11 . That is, on the side of the turning piece 12 away from the base 11, that is, on the side of the upper surface of the turning piece 12, a first abutment column 121 may be formed, so that after the turning piece 12 is turned over, it can be easily connected with the electrical connection as described later. The abutment of member 40 (shown in conjunction with Figures 1 and 2) triggers the fuse to interrupt charging.

As mentioned above, the reversing piece 12 can be set to be electrically connected to the first pole 20 and the second pole 30 of the power battery after being turned over, so that it can be made of a conductive material, such as a metal material that is easily deformed elastically, such as Aluminum or stainless steel.

Wherein, the base 11 may be a heat conduction base 11 . That is, during the charging process, the reversing plate 12 is usually installed towards the inside of the battery, and the heat generated by charging is mainly transferred to the accommodating space 14 through the base 11, so it can be selected to have relatively good thermal conductivity. For example, it can be made of aluminum It is made of metal such as stainless steel or stainless steel, so as to achieve good thermal conductivity at a low cost, and ensure that the generated heat can be transferred to the elastic member 13 in the accommodation space 14 in time under the overcharged state.

Of course, it is also possible to open a through hole on the second turning piece 12 so that when the battery is overcharged, the high-temperature gas inside the battery enters the accommodating space 14, and the hot-melt part 131 can also be melted by the high-temperature gas, thereby realizing a compression spring. release.

The flipper assembly 10 described above can be applied to the battery cover assembly 100 to act when the battery is in a relatively low overcharged state to terminate charging of the battery.

As shown in FIG. 1 , the battery cover plate assembly 100 of the second embodiment of the present invention includes: a first pole 20 , a second pole 30 and a reversing piece assembly 10 , a reversing piece 12 and a first pole 20 It is electrically connected, and is suitable for being electrically connected with the second pole 30 at a predetermined temperature. Wherein, the flipping sheet assembly 10 is installed so that the flipping sheet 12 is electrically connected to the first pole 20 in the initial state, and when the elastic member 13 in the accommodation space 14 is partially melted by heat, the flipping sheet 12 is turned upside down and connected to the second pole. 30, so that the first pole 20 and the second pole 30 are electrically connected, so that the external circuit of the battery forms a short circuit, triggering the fuse to interrupt charging, so that the power battery can be terminated when it is in a low overcharge state. , to avoid safety issues such as further reaction of battery internal materials at high temperature and subsequent battery thermal runaway, which effectively improves charging safety.

It can be understood that the reversing sheet assembly 10 of the present utility model can also terminate battery charging in other ways, such as setting a switch that can control the start and stop of charging at the position opposite to the reversing sheet 12, so as to trigger the switch after the reversing sheet 12 is turned over. while terminating battery charging, etc.

Wherein, as shown in FIG. 1 and FIG. 2 , the battery cover plate assembly 100 also includes: an electrical connector 40 , the electrical connector 40 is arranged at one end of the second pole 30 and is electrically connected to the second pole 30 , and electrically connected to the second pole 30 . The member 40 is electrically connected to the flipping piece 12 at a predetermined temperature. In this way, the electrical connector 40 is an electrical conductor, that is, a part of the electrical connector 40 can be electrically connected to the second pole 30, and can be electrically connected to the electrical connector 40 after the flipping piece 12 is flipped, so that it can pass through the flipping piece. 12 and the electrical connector 40 electrically connect the first pole 20 and the second pole 30 together, so as to realize the short circuit of the battery cover plate assembly 100 .

Wherein, one of the limiting protrusion and the limiting groove is set on the second pole 30, and the other one of the limiting protrusion and the limiting groove is set on the electrical connector 40, and the limiting protrusion The limit fit between the protrusion and the limit groove, so that the electrical connection between the electrical connector 40 and the second pole 30 can be realized through the limit fit between the limit protrusion and the limit groove.

And, referring to FIG. 2 , a second abutment post 41 is formed on a side of the electrical connector 40 facing the turning piece 12 . In this way, the second abutting post 41 facing the flipping piece 12 is set on the electrical connector 40, and the first abutting post 121 and the second abutting post 41 are oppositely arranged, so that when the flipping piece 12 is turned over, the first abutting post 41 121 and the second abutting column 41 can abut against each other, so as to realize the electrical connection between the turning piece 12 and the electrical connector 40 . Moreover, the second abutting post 41 is provided on the electrical connector 40, so that the turning stroke of the turning piece 12 can be reduced, that is, when the turning piece 12 is turned over, the turning piece 12 can directly abut against the second abutting post 41 .

In addition, as shown in FIG. 1 , the battery cover plate assembly 100 also includes: a cover plate 50 and an insulating plate 60 , the insulating plate 60 is arranged on one side of the cover plate 50 , the first pole 20 is arranged on the cover plate 50 , and the second One pole 20 is electrically connected to the cover plate 50 , the electrical connector 40 is disposed on the cover plate 50 , and the flipper assembly 10 is electrically connected to the cover plate 50 , and the second pole 30 is disposed on the insulating plate 60 . Wherein, the cover plate 50 is covered on the top of the insulating plate 60, and the flipper assembly 10 is electrically connected to the cover plate 50, and since the cover plate 50 is electrically connected to the first pole 20, the flipper assembly 10 and the cover plate can be realized in this way. Electrical connection between 50. Moreover, the second pole 30 is disposed on the insulating plate 60, so that the second pole 30 and the first pole 20 are insulated from each other.

Wherein, in the above embodiments, the first pole 20 and the second pole 30 are located on the same side, that is, the first pole 20 and the second pole 30 are arranged on the same battery cover plate assembly 100 .

Of course, the first pole 20 and the second pole 30 can also be arranged at both ends of the battery. Specifically, the flipper assembly 10 is electrically connected to the cover plate 50 at one end, wherein the cover plate 50 at one end is connected to the cover plate 50 at the other end through the casing, and the cover plate 50 at the other end is electrically connected to the first pole 20 In this way, the selective electrical connection of the first pole 20 and the second pole 30 can be realized through the cover plate 50 at both ends of the battery, the shell, the flip assembly 10 and the electrical connector 40 .

The battery in the embodiment of the third aspect of the utility model includes: a housing, a battery cell and a battery cover assembly 100, the housing has a housing cavity and an opening communicating with the housing cavity, the battery core is arranged in the housing cavity, and the battery cover plate assembly The 100 cover is arranged at the opening. Wherein, the battery cell is arranged in the casing, and the battery cell and the battery cover plate assembly 100 are arranged oppositely, so that the high temperature generated when the battery is overcharged can be directly transmitted to the flipper assembly 10, thereby melting the hot-melt part 131, so that The elastic part 132 generates an elastic force and abuts against the turning piece 12, so that the turning piece 12 is turned over and then electrically connects the first pole 20 and the second pole 30 through the turning piece 12, the electrical connector 40 and the cover plate 50, thereby Short-circuit the battery to realize the anti-overcharge function of the battery.

The short-circuit device provided by the utility model will be further described in detail below through specific experiments as examples and in conjunction with the accompanying drawings.

Embodiment 1: Both the turning piece 12 and the base 11 are made of aluminum metal. The distance between the upper surface of the base 11 and the lower surface of the turning piece 12 is 3mm. The elastic member 13 is a PCL plastic and a compression spring sealed therein. The base 11 adopts a cylindrical base 11 . The way of connecting and fixing the turning piece 12 and the base 11 is glued. In this way, the flip sheet assembly 10A1 is produced.

Lithium cobalt oxide is used as the positive electrode active material to make the positive electrode sheet, graphite is used as the negative electrode active material to make the negative electrode sheet, and the ceramic diaphragm is used as the diaphragm, the flip sheet assembly 10A1 is assembled into the cover plate 50, and the new lithium ion battery S10 is packaged by liquid injection.

Embodiment 2: Both the turning piece 12 and the base 11 are made of aluminum metal. The distance between the upper surface of the base 11 and the lower surface of the turning piece 12 is 5mm. The elastic member 13 is a PCL plastic and a compression spring sealed therein. The base 11 adopts a truncated round bottom. The way of connecting and fixing the turning piece 12 and the base 11 is glued. In this way, the flip sheet assembly 10A2 is produced.

Lithium cobaltate is used as the positive electrode active material to make the positive electrode sheet, graphite is used as the negative electrode active material to make the negative electrode sheet, and the ceramic diaphragm is used as the diaphragm, the flip sheet assembly 10A2 is assembled into the cover plate 50, and the new lithium ion battery S20 is packaged by liquid injection.

Embodiment 3: Both the turning piece 12 and the base 11 are made of aluminum metal. The distance between the upper surface of the base 11 and the lower surface of the turning piece 12 is 7mm. The elastic member 13 is a PCL plastic and a compression spring sealed therein. The base 11 adopts a cylindrical bottom. The way of connecting and fixing the turning piece 12 and the base 11 is glued. In this way, the flip sheet assembly 10A3 is produced.

Lithium cobaltate is used as the positive electrode active material to make the positive electrode sheet, graphite is used as the negative electrode active material to make the negative electrode sheet, and the ceramic diaphragm is used as the diaphragm, the flip sheet assembly 10A3 is assembled into the cover plate 50, and the new lithium ion battery S30 is packaged by liquid injection.

Comparative Example 1: The battery sample DS10 was fabricated according to the method in Example 1, except that the flipping sheet 12 used was a traditional flipping sheet 12 .

The DS10 battery using the traditional flip 12 fuses the external circuit fuse in the 40th minute, so that the charging is terminated. However, due to the high degree of overcharging, the internal short circuit of the battery is serious. As the internal reaction of the battery continues to occur, the heat and gas production of the battery The accumulation continued, and finally the explosion-proof valve opened in the 46th minute, and a fire exploded in the 47th minute. However, for the S10 battery using the reversible sheet 12, due to the rapid rise of the internal temperature of the battery during overcharging, the elastic member 13PCL plastic in the sealed space of the reversible sheet 12 melts, and the stretching of the compressed spring pushes the reversible sheet 12 to turn over, making the battery outside the circuit in 24 minutes. A short circuit blows the fuse and terminates charging.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial ", "radial", "circumferential" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, which are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying No device or element must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the invention.

In the description of this specification, references to the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific examples," or "some examples" are intended to mean that the implementation Specific features, structures, materials or characteristics described in an embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and modifications, the scope of the present invention is defined by the claims and their equivalents.

Claims (10)

1. A turn-over sheet assembly, characterized in that, comprising: Flip sheet; a base, and the base is sealingly connected with the turning piece to form an accommodating space; an elastic member, the elastic member is arranged in the accommodating space and abuts between the turning piece and the base, and the elastic member is adapted to be deformed at a predetermined temperature so that the turning piece moves away from One side of the base is turned over. 2. The turning plate assembly according to claim 1, wherein the elastic member comprises: a hot-melt part and an elastic part, the hot-melt part is wrapped around the outside of the elastic part, and the hot-melt part is suitable for Melts at a predetermined temperature. 3 . The turning plate assembly according to claim 1 , wherein the maximum distance between the surfaces of the base and the turning plate facing each other is h, and h satisfies the relation: 1mm≤h≤10mm. 4 . The turning plate assembly according to claim 1 , wherein a first abutting post is provided on a side of the turning plate facing away from the base. 5. The turning plate assembly according to claim 1, wherein the base is a heat conducting base. 6. A battery cover assembly, characterized in that it comprises: first pole; a second pole opposite in polarity to the first pole; The flipping sheet assembly according to any one of claims 1-5, wherein the flipping sheet is electrically connected to the first pole, and is adapted to be electrically connected to the second pole at a predetermined temperature. 7. The battery cover assembly according to claim 6, further comprising: an electrical connector, the electrical connector is arranged at one end of the second pole and is electrically connected to the second pole. connected, the flipping piece is electrically connected to the electrical connector at a predetermined temperature. 8 . The battery cover assembly according to claim 7 , wherein a second abutment post is formed on a side of the electrical connector facing the flipping piece. 9. The battery cover plate assembly according to claim 6, further comprising: a cover plate and an insulating plate, the insulating plate is arranged on one side of the cover plate, and the first pole is arranged on The cover plate is electrically connected with the cover plate, the flipping plate assembly is arranged on the cover plate and electrically connected with the cover plate, and the second pole is arranged on the insulating plate. 10. A battery, characterized in that it comprises: a housing, the housing having a receiving cavity and an opening communicating with the receiving cavity; an electric core, the electric core is arranged in the accommodating cavity; The battery cover assembly according to any one of claims 6-9, wherein the battery cover assembly covers the opening.

Images