WO2019192204A1

WO2019192204A1 - Cap assembly for battery, and battery

Info

Publication number: WO2019192204A1
Application number: PCT/CN2018/119008
Authority: WO
Inventors: 王生义; 姬国庆
Original assignee: 广东微电新能源有限公司
Priority date: 2018-04-02
Filing date: 2018-12-03
Publication date: 2019-10-10
Also published as: CN208111494U

Abstract

Provided are a cap assembly for a battery, and a battery. The cap assembly comprises a first cap body and a second cap body, with the first cap body and the second cap body being attached to each other and in electrical connection. A cavity is formed between the first cap body and the second cap body; the first cap body is provided with a protruding portion protruding in a direction away from the cavity and a vent hole in communication with the cavity; a through hole that is in communication with the cavity is arranged in the second cap body; a sealing member is arranged in the through hole; and the second cap body is configured to be connected to a cell.

Description

Cap assembly for battery and battery

Technical field

The present application relates to the field of energy storage devices, and more particularly, to a cap assembly for a battery and a battery.

Background technique

Existing cylindrical batteries typically include a cap and a housing. The cap acts as an electrode for the battery. The cap is insulated from the housing of the battery. In order to protect the battery, it is usually necessary to connect a PCM (protection unit). Conductive vias for electrical connections are provided on the PCM's circuit board. A conductor such as a nickel piece is welded to the cap. The cap is connected to the conductive via through a nickel sheet. In assembly, first, the cap is assembled to the housing and the current collector of the battery is electrically connected to the cap. Then, one end of the nickel piece was welded to the cap, and the other end of the nickel piece was passed through the conductive via. Finally, the other end of the nickel piece is soldered in the conductive via.

However, when the nickel piece is welded to the cap, assembly deviation usually occurs, and the other end of the conductor cannot be accurately passed through the conductive via at the time of automatic production, and the yield of the battery is low. Existing caps are not conducive to automation, mass production.

Therefore, it is necessary to provide a technical solution to solve the above technical problems.

Application content

It is an object of the present application to provide a new technical solution for a cap assembly for a battery.

According to one aspect of the present application, a cap assembly for a battery is provided. The cap assembly includes a first cover body and a second cover body, the first cover body and the second cover body are attached together, and are electrically connected to each other, in the first cover body and the second cover body Forming a cavity inside, the first cover body is provided with a convex portion protruding in a direction away from the cavity and a vent hole communicating with the cavity, and the second cover body is provided with A through hole communicating with the cavity, a seal is disposed in the through hole, and the second cover is configured to be connected to the battery.

Optionally, the first cover body and the convex portion are integrally formed.

Optionally, the first cover body includes a first edge portion and a first center portion protruding from the first edge portion, and the protrusion portion is disposed at the first center portion.

Optionally, a through hole and the vent hole are disposed in the first central portion, and further includes an L-shaped bent piece, one edge of the L-shaped bent piece passes through the through hole to form the a raised portion, and the other side is located inside the first central portion, and the other side is fixedly coupled to the first central portion.

Optionally, a through hole and the vent hole are disposed in the first central portion, and further includes a rivet, the rivet includes a stem and a cap connected to one end of the stem, the stem is from the The inner side of the first central portion is outwardly passed through the through hole to form the convex portion, and the cap portion is fixed inside the first central portion.

Optionally, the second cover body includes a second edge portion and a second center portion protruding from the second edge portion, the through hole is disposed at the second center portion, the first edge And the second edge portion are fitted together, the first central portion and the second central portion are disposed opposite to each other, and the cavity is formed between the first central portion and the second central portion body.

Optionally, a heat sensitive material is disposed at a portion where the first cover body and the second cover body are in contact with each other.

Optionally, the seal is a ball that snaps into the through hole and forms a seal.

Optionally, the method further includes an insulating ring sleeved on an edge of the first cover and an edge of the second cover, the insulating ring being away from the first cover in the second cover One side forms a ring stop.

According to another aspect of the present application, a battery is provided. The battery includes a housing, a battery core, and the cap assembly provided by the present application, the housing has a cylindrical structure, the battery core is disposed in the cylindrical structure, and the cap assembly is disposed at An open end of the housing, one electrode of the battery core is electrically connected to the second cover.

Optionally, the housing is electrically connected to another electrode of the battery core, and a pole piece is protruded on the housing.

One technical effect of the present application is that the first cover body is provided with a convex portion. The boss is convexly disposed at a set position of the first cover. The set position allows the projection to be accurately inserted into the conductive via of the PCM when the battery is mounted. In this way, the position of the boss can be more fixed, avoiding soldering the conductor connected to the PCM after the battery assembly is completed. This makes it easy to connect the battery to the PCM and adapt to the mass production of the battery.

Other features and advantages of the present application will become apparent from the following detailed description of the exemplary embodiments.

DRAWINGS

The accompanying drawings, which are incorporated in FIG

1 is a cross-sectional view of a cap in accordance with an embodiment of the present application.

2 is a bottom view of a first cover in accordance with an embodiment of the present application.

Figure 3 is a cross-sectional view taken along line A-A of Figure 2;

4 is an L-shaped bent piece in accordance with an embodiment of the present application.

FIG. 5 is a schematic structural view of another first cover according to an embodiment of the present application.

Figure 6 is a view of another angle of Figure 5.

Figure 7 is a cross-sectional view of a battery in accordance with one embodiment of the present application.

FIG. 8 is a schematic structural view of a battery according to an embodiment of the present application.

Description of the reference signs:

11: first cover; 12: second cover; 13: cavity; 14: raised portion; 16: ball; 18: first edge portion; 19: first central portion; 20: venting hole; : L-shaped bent piece; 21a: first: 21b: second side; 21c: notch; 22: second edge portion; 23: second central portion; 24: insulating ring; 25: annular retaining wall; Housing; 27: pole piece; 29: positive current collector; 30: negative current collector; 31: battery; 32: insulating sheet.

detailed description

Various exemplary embodiments of the present application will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components and steps, numerical expressions and numerical values set forth in the embodiments are not intended to limit the scope of the application.

The following description of the at least one exemplary embodiment is merely illustrative and is in no way

Techniques and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques and devices should be considered as part of the specification.

In all of the examples shown and discussed herein, any specific values are to be construed as illustrative only and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that similar reference numerals and letters indicate similar items in the following figures, and therefore, once an item is defined in one figure, it is not required to be further discussed in the subsequent figures.

In accordance with an embodiment of the present application, a cap assembly for a battery is provided. The cap is located on the end face of the battery to seal the battery. For example, the cap forms at least one of a positive electrode and a negative electrode of the battery.

As shown in FIG. 1, the cap assembly includes a first cover 11 and a second cover. The first cover 11 and the second cover 12 are attached together and are electrically connected. For example, the first cover 11 and the second cover 12 are parallel or approximately parallel to each other. Both the first cover 11 and the second cover 12 have a flat structure. The edge of the first cover 11 and the edge of the second cover 12 are in contact with each other to form an electrical connection. It is also possible that the other parts of the two covers are in contact with each other.

The first cover 11 and the second cover 12 are each made of a conductor. For example, metal, conductive glass, and the like. Preferably, the first cover 11 and the second cover 12 are made of a copper alloy, an aluminum alloy or stainless steel.

A cavity 13 is formed inside the first cover 11 and the second cover 12. A boss portion 14 that protrudes away from the cavity 13 is provided on the first cover body 11. The cavity 13 may be a space having a receiving function or a gap between the two covers.

The boss 14 is made of a conductor. For example, the raised portion 14 is in the form of a sheet, a needle, or other shape that facilitates insertion. Those skilled in the art can make settings according to actual needs.

A vent hole 20 communicating with the cavity 13 is provided on the first cover 11. Those skilled in the art can set the shape and size of the venting holes 20 according to actual needs.

A through hole communicating with the cavity 13 is provided on the second cover 12. The through hole is for connecting the inside of the battery to the cavity 13. A seal is provided in the through hole. When the air pressure in the battery exceeds a set value, for example, 2 atmospheres, the seal is broken or the seal is released from the through hole, thereby releasing the gas into the cavity 13, thereby reducing the explosion due to excessive air pressure inside the battery. risk. The gas inside the battery can be directly released into the external space through the vent hole 20, which further reduces the risk of explosion of the battery.

In the embodiment of the present application, the first cover 11 is provided with a convex portion 14. The boss portion 14 is protruded from the set position of the first cover 11 . This set position allows the boss 14 to be accurately inserted into the conductive via of the PCM when the battery is mounted. In this way, the position of the boss 14 can be more fixed, avoiding soldering the conductor connected to the PCM after the battery assembly is completed. This makes it easy to connect the battery to the PCM and adapt to the mass production of the battery.

In one example, the first cover 11 and the raised portion 14 are integrally formed. For example, as shown in FIGS. 2-3, the first cover 11 is made of a metal plate. The boss portion 14 is punched out by press forming, and the vent hole 20 is formed at a portion where the boss portion 14 originally. In this way, the processing of the first cover 11 becomes easy.

In one example, as shown in FIGS. 2-3, the first cover 11 includes a first edge portion 18 and a first central portion that protrudes from the first edge portion 18. The boss portion 14 is provided at the first center portion 19. The first cover 11 is attached to the second cover 12, and a cavity 13 is formed between the first central portion 19 and the central portion of the second cover 12. The raised portion 14 protrudes from the first central portion 19.

In one example, the first central portion 19 is provided with a through hole and a vent hole 20. The cap assembly also includes an L-shaped bent piece 21. One side of the L-shaped bent piece 21 passes through the through hole to form the convex portion 14, and the other side is located inside the first center portion 19. The other side is fixedly connected to the first central portion 19.

For example, as shown in FIGS. 4-6, the L-shaped bent piece 21 is stamped from sheet metal, and includes a first side 21a and a second side 21b joined together. The metal sheet is selected from the group consisting of aluminum, copper, nickel, steel, gold, silver, magnesium, and alloys of the above various elements.

Among them, the first side 21a passes through the flat through hole from the inner side of the first center portion 19, thereby forming the boss portion 14. The inner side is the side close to the second cover 12. The second side 21b is located inside the first center portion 19 and is fixed to the first center portion 19. For example, the second side 21b is fixedly coupled to the first center portion 19 by laser welding, electric resistance welding, ultrasonic welding or the like.

Two vent holes 20 are provided in the first central portion 19. The two venting holes 20 can also serve as a gripping point for grasping the first cover body 11 to facilitate automatic feeding of the first cover body 11 and to switch between different stations. A notch 21c for escaping the two vent holes 20 is also provided on the second side 21b. Thus, the L-shaped bent piece does not hinder the release of gas inside the battery.

In this example, the first side 21a and the second side 21b have a set angle. The second side 21b is fixed to the first central portion 19, and the first side 21a does not need to be machined, so that the structure of the first side 21a is not affected, so that the position of the first side 21a is more accurate.

In one example, the cap assembly also includes a rivet. The rivet includes a stem and a cap attached to one end of the stem. The stem protrudes outward from the inner side of the first center portion 19 through the through hole to form the boss portion 14. The cap portion is fixed to the inner side of the first center portion 19. For example, the cap portion is welded inside the first center portion 19. In this way, the position of the boss 14 can also be ensured to be more precise.

The shape of the cap portion may be a mushroom head shape, a circle shape, a square shape, a triangle shape, a hexagon shape, or the like. The material of the rivet is selected from the group consisting of aluminum, copper, nickel, steel, gold, silver, magnesium, and alloys of the above various elements. Those skilled in the art can make settings according to actual needs.

In one example, as shown in FIG. 1, the second cover 12 includes a second edge portion 22 and a second central portion 23 that protrudes from the second edge portion 22. The through hole is provided in the second center portion 23. The first edge portion 18 and the second edge portion 22 are fitted together, and the first central portion 19 and the second central portion 23 are disposed opposite each other, and a cavity 13 is formed between the first central portion 19 and the second central portion 23. In this way, the volume of the cavity 13 is larger, and the air pressure inside the battery can be more effectively buffered.

Preferably, a heat sensitive material is provided at a portion where the first cover 11 and the second cover 12 are bonded to each other. For example, a heat sensitive material is disposed between the first edge portion 18 and the second edge portion 22. When the battery is short-circuited, overcharged, over-discharged, and the ambient temperature rises or falls, the current of the battery increases. When the internal temperature rises, the resistance of the heat-sensitive material increases, reducing the magnitude of the current, thereby protecting the battery.

For example, the heat sensitive material includes an alloy material of Mo-Co-Ni-Cu or the like which can increase the electrical resistance of the cap assembly when the ambient temperature is too high.

The heat sensitive material may also be BaTiO ₃ , SnO-SbO or the like, and the above material can increase the electrical resistance of the cylindrical current collector when the ambient temperature is too low.

The heat sensitive material is not limited to the above, and those skilled in the art can select according to actual needs.

Thermally sensitive materials can further improve the safety of the battery. The heat-sensitive material and the PCM form a double protection of the battery, so that even if one of them fails, the other can effectively protect the battery.

The heat sensitive material may be coated on at least one of the first edge portion 18 and the second edge portion 22. The heat sensitive material may be applied locally or over the entire annular surface. It is also possible to apply different types of heat sensitive materials to different parts of the annular surface so that the battery can be protected if the temperature is too high or too low.

In one example, the seal is a ball 16. For example, as shown in FIG. 1, the ball 16 is made of a hard material such as a steel ball, a copper ball, or an aluminum ball. The ball 16 is caught in the through hole and is interference-fitted with the through hole to form a seal. The ball 16 faces the venting opening 20. When the pressure inside the battery is too high, the ball 16 is ejected from the through hole to release the pressure.

In other examples, the ball 16 can also be fabricated from materials such as rubber, silicone, plastic, and the like. The above materials can also act as a pressure relief.

In one example, the cap assembly further includes an insulating ring 24 that is sleeved over the edge of the first cover 11 and outside of the edge of the second cover 12. The insulating ring 24 forms an annular retaining wall 25 on a side of the second cover 12 remote from the first cover 11. For example, as shown in FIG. 1, an insulating ring 24 is sleeved on the outer side of the first edge portion 18 and the second edge portion 22. For example, the insulating ring 24 is made of a material such as plastic, rubber or silica gel by injection molding. Insulation ring 24 is used to insulate between housing 26 of the battery and the cap assembly.

In this example, the annular barrier wall 25 projects toward the cell 31 adjacent to the battery. When assembling the cap, it is necessary to weld the current collector of the cell 31 (e.g., the positive current collector 29) to the second cover 12 of the cap. Normally, the cathode current collector 29 protrudes from the cell 31. When the welding is performed, the cathode current collector 29 needs to be positioned with the second lid body 12. The annular retaining wall 25 can form a stop for the current collector and form an isolation between the current collector and the housing 26. Thus, the current collector can be effectively prevented from coming into contact with the casing 26 of the battery, and the contact position of the current collector with the second cover 12 can be made more accurate.

According to another embodiment of the present application, a battery is provided. As shown in Figures 7-8, the battery includes a housing 26, a battery cell 31, and a cap assembly provided herein. The housing 26 has a cylindrical structure. The battery cell 31 is disposed within the cylindrical structure. A cap assembly is disposed at the open end of the housing 26. One electrode of the battery cell 31 is electrically connected to the second cover body 12. An insulating sheet 32 is disposed between the upper and lower ends of the battery cell 31 and the casing.

In one example, both ends of the housing 26 are open ends. A cap assembly is provided for each of the two open ends, one of which serves as a positive electrode and the other as a negative electrode.

In one example, the housing 26 is electrically coupled to the other electrode of the cell 31. For example, the housing 26 has a cylindrical structure that is open at one end. A cap assembly is provided at the open end. The second housing 26 of the cap assembly is electrically coupled to the positive current collector 29. The anode current collector 30 is electrically connected to the housing 26. Thus, the cap assembly acts as the positive pole of the battery and the housing 26 acts as the negative pole of the battery. In this example, the battery further includes a pole piece 27 projecting from the housing 26. The pole piece 27 and the boss portion 14 can be electrically connected to the PCM or other external device by plugging, which makes the installation of the battery easy.

Although the specific embodiments of the present application have been described in detail by way of example, those skilled in the art should understand that the above examples are only for the purpose of illustration and not limitation. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the application. The scope of the application is defined by the appended claims.

Claims

A cap assembly for a battery, comprising: a first cover body and a second cover body, wherein the first cover body and the second cover body are attached together, and the two are electrically connected, in the a cover body and a cavity of the second cover body form a cavity, and the first cover body is provided with a convex portion protruding in a direction away from the cavity and a vent hole communicating with the cavity. A through hole communicating with the cavity is disposed on the second cover body, and a sealing member is disposed in the through hole, and the second cover body is configured to be connected to the battery core.
The cap assembly of claim 1 wherein said first cover and said raised portion are integrally formed.
The cap assembly according to claim 2 or 3, wherein the first cover body includes a first edge portion and a first center portion protruding from the first edge portion, the boss portion being Provided in the first central portion.
The cap assembly according to any one of claims 1 to 3, wherein the first central portion is provided with a through hole and the vent hole, and further includes an L-shaped bent piece, the L One side of the bent piece passes through the through hole to form the convex portion, and the other side is located inside the first central portion, and the other side is fixedly connected to the first central portion .
A cap assembly according to any one of claims 1 to 4, wherein a through hole and the vent hole are provided in the first central portion, further comprising a rivet, the rivet including a stem and a cap portion connected to one end of the stem, the stem being outwardly passed out from the inner side of the first center portion via the through hole to form the boss portion, the cap portion being fixed at the The inner side of the first center portion is described.
The cap assembly according to any one of claims 1 to 5, wherein the second cover body includes a second edge portion and a portion protruding from the second edge portion a second central portion, the through hole is disposed at the second central portion, the first edge portion and the second edge portion are fitted together, and the first central portion and the second central portion are The back is disposed to form the cavity between the first central portion and the second central portion.
The cap assembly according to any one of claims 1 to 6, wherein a heat sensitive material is provided at a portion where the first cover and the second cover are bonded to each other.
A cap assembly according to any of claims 1-7, wherein the seal is a ball that snaps into the through hole and forms a seal.
The cap assembly according to any one of claims 1 to 8, further comprising an insulating ring sleeved on an edge of the first cover and an outer side of the edge of the second cover, The insulating ring forms an annular barrier wall on a side of the second cover that is away from the first cover.
A battery comprising a housing, a battery core, and a cap assembly according to any one of claims 1 to 9, the housing having a cylindrical structure, the battery core being disposed at the In the cylindrical structure, the cap assembly is disposed at an open end of the housing, and one electrode of the battery is electrically connected to the second cover.
A battery according to claim 10, wherein said housing is electrically connected to the other electrode of said battery cell, and a pole piece is protruded from said housing.