WO2022206951A1

WO2022206951A1 - Battery cover plate, battery, and preparation method for battery

Info

Publication number: WO2022206951A1
Application number: PCT/CN2022/084799
Authority: WO
Inventors: 杨昆仑; 李正冬; 陈志勇
Original assignee: 广东微电新能源有限公司
Priority date: 2021-04-02
Filing date: 2022-04-01
Publication date: 2022-10-06
Also published as: CN113013526A; CN113013526B

Abstract

Provided are a battery and a preparation method for the battery. A battery cover plate (1) comprises: a cover plate (11), a first through hole (111) running through the cover plate (11) in a thickness direction of the cover plate (11); a base (121), at least a part of the base (121) being located in the first through hole (111), and an insulating member (13) being provided between the base (121) and the cover plate (11); a second through hole (123) running through the base (121) in a thickness direction of the base (121); and a cap (122), at least a part of the cap (122) being located in the second through hole (123) and detachably connected to the base (121), and the cap (122) and the base (121) are in a separated state, the second through hole (123) serving as a liquid injection hole.

Description

Battery cover, battery, and method for preparing battery

This application claims the priority of the Chinese patent application filed on April 2, 2021 with the application number 202110362208.8 and the application title is "battery cover plate, battery and method for preparing battery", the entire contents of which are incorporated by reference in in this application.

technical field

The present disclosure relates to the technical field of batteries, and in particular, to a battery cover plate, a battery having the battery cover plate, and a method for preparing the battery.

Background technique

Lithium-ion battery is a large-capacity, high-power battery, which is mainly used in small devices, such as lithium-ion batteries can be applied to mobile phones. Lithium-ion batteries are generally composed of a battery cover plate assembly, a battery tank, an electrolyte, and a battery core wound by positive and negative electrode sheets and separator paper.

The battery cover is provided with an opening, and the opening is provided with a cap. The cap is used as an electrode of the battery to draw out the current. At the same time, an additional through hole needs to be provided on the battery cover as a liquid injection hole. Therefore, the battery assembly process in the prior art is cumbersome and the battery The strength of the cover plate is low.

SUMMARY OF THE INVENTION

An object of the present disclosure is to provide a battery cover plate, a battery having the battery cover plate, and a preparation method of the battery.

According to a first aspect of the present disclosure, a battery cover is provided. The battery cover includes:

a cover plate, wherein the cover plate penetrates along the thickness direction to form a first through hole;

a base, at least a part of the base is located in the first through hole, an insulating member is arranged between the base and the cover plate; the base passes through the base along the thickness direction to form a second through hole;

a cap, at least a part of the cap is located in the second through hole and is detachably connected to the base, and when the cap is separated from the base, the second through hole is used as a liquid injection hole.

Optionally, a connecting portion is provided between the base and the cap.

Optionally, an inner thread is formed on the inner wall of the second through hole, an outer thread is formed on at least a part of the outer wall of the cap, and the base and the cap are threadedly connected.

Optionally, the cap is embedded in the second through hole, and a sealing film is provided between the cap and the base.

Optionally, the insulator is provided on the inner peripheral surface of the first through hole, and at least one of the two ends of the insulator extends outward along the radial direction of the first through hole and covers the surface of the cover.

Optionally, along the axial direction of the first through hole, the insulating member further includes an insulating support arm;

An accommodating groove is formed along the thickness direction of the cover plate, and the insulating support arm is embedded in the accommodating groove.

Optionally, the base includes a first base and a second base connected to the first base;

The first base is connected to the cover plate, and the second base penetrates the first through hole.

Optionally, a first connecting surface is formed on a side of the first base close to the second base, a second connecting surface is formed on a side of the second base close to the first base, and the The first connecting surface and the second connecting surface are oppositely arranged and connected;

Along the radial direction of the first through hole, the size of the first connection surface is larger than the size of the second connection surface, and the first connection surface is arranged above the tab for electrically connecting with the tab. connect.

Optionally, the insulating member is disposed on the inner peripheral surface of the first through hole, and the upper end of the insulating member extends outward along the radial direction of the first through hole and covers the outer surface of the cover plate.

Optionally, the cover plate, the base and the insulating member are integrally formed.

According to a second aspect of the present disclosure, there is provided a battery. The battery includes: a casing and the battery cover described in the first aspect;

An opening is formed on one side of the casing, the battery cover plate covers the opening, and the cover plate is welded with the casing.

Optionally, when the battery cover covers the opening, at least a part of the base extends into the casing.

According to a third aspect of the present disclosure, a method for manufacturing a battery is provided. The method includes the steps:

a casing is provided, and the casing is provided with an electric core;

A battery cover is provided, the cover is welded with the casing, and the base is isolated from the cover by an insulating member;

The electrolyte is injected into the casing through the second through hole on the base;

A cap is arranged in the second through hole to seal the battery.

Optionally, before the step of injecting electrolyte into the casing through the second through hole on the base, the method further includes:

The positive ear of the battery cell is welded to the base, and the negative electrode ear of the battery core is welded to the cover plate or the casing.

Weld the negative lug of the battery cell with the cover plate or the shell;

After the step of disposing the cap in the second through hole to seal the battery, the method further includes:

Weld the positive lug of the cell to the cap.

Beneficial effects of the present disclosure: A battery cover plate provided by the present disclosure includes a cover plate, an insulating member, a base and a cap. The base and the cap are detachably connected, and the electrolyte is injected through the second upper through hole of the base when the cap and the base are not assembled. Compared with the prior art, the battery cover plate of this example does not need to separately open through holes on the cover plate as liquid injection holes, which improves the strength of the battery cover plate.

Other features of the present disclosure and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1 is a schematic diagram of an internal structure of a battery according to an embodiment of the present disclosure.

FIG. 2 is a schematic structural diagram of the combination of the cover plate and the casing of the battery of the present disclosure.

FIG. 3 is a schematic structural diagram of the combination of the base and the cover plate of the battery of the present disclosure.

FIG. 4 is a schematic structural diagram of the battery shown in FIG. 1 .

FIG. 5 is a schematic diagram showing the internal structure of a battery according to still another embodiment of the present disclosure.

FIG. 6 is a schematic structural diagram of the battery shown in FIG. 5 .

FIG. 7 is a schematic structural diagram of a battery cover plate of the battery shown in FIG. 5 .

FIG. 8 is a schematic diagram showing the internal structure of a battery according to still another embodiment of the present disclosure.

FIG. 9 is a schematic structural diagram of the battery shown in FIG. 8 .

Description of reference numbers:

1. Battery cover; 11. Cover; 111, First through hole; 12, Metal terminal; 121, Base; 122, Cap; 123, Second through hole; 124, Sealing film; 13, Insulator; 131 , insulating arm; 2, shell; 3, cell; 31, tab; 1211, first base; 1212, second base.

Detailed ways

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the disclosure, its application or uses in any way.

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

In all examples shown and discussed herein, any specific values should be construed as illustrative only and not limiting. Accordingly, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further discussion in subsequent figures.

According to one embodiment of the present disclosure, a battery cover is provided. Referring to FIGS. 1-9 , the battery cover 1 includes: a cover 11 , a base 121 , a cap 122 and an insulating member 13 .

A first through hole 111 is formed through the cover plate 11 along its thickness direction. At least a part of the base 121 is located in the first through hole 111 . An insulating member 13 is disposed between the base 121 and the cover 11 . A second through hole 123 is formed through the base 121 along its thickness direction. At least a part of the cap 122 is located in the second through hole 123 and is detachably connected to the base 121 . When the cap 122 is separated from the base 121, the second through hole 123 is used as a liquid injection hole.

Specifically, as shown in FIG. 2 , the cover plate 11 is provided with a first through hole 111 , and the first through hole 111 penetrates along the thickness direction of the cover plate 11 . At least a part of the base 121 is located in the first through hole 111 , that is to say, the base 121 may be entirely disposed in the first through hole 111 , or may be partially disposed in the first through hole 111 . In the case where at least a part of the base 121 is located in the first through hole 111, an insulating member 13 is provided between the base 121 and the cover 11. The insulating member 13 isolates the base 121 and the cover 11, and the insulating member 13 avoids the The seat 121 is in direct contact with the cover plate 11 . When the battery cover plate 1 is applied to a battery, the base 121 and the cover plate 11 are isolated by the insulating member 13 , so as to avoid the short circuit of the battery caused by the contact between the base 121 and the cover plate 11 . In one embodiment, the material of the cover plate 11 is a metal material. For example, the material of the cover plate 11 can be selected from a steel material or an aluminum material.

Referring to FIG. 3 , a second through hole 123 is formed on the base 121 , and the second through hole 123 penetrates along the thickness direction of the base 121 . At least a part of the cover cap 122 is located in the second through hole 123 , that is, the cover cap 122 may be completely located in the second through hole 123 , or may be partially located in the second through hole 123 .

The cap 122 and the base 121 are detachably connected, so the cap 122 and the base 121 can be in a mutually assembled state or in a separated state.

When the cap 122 and the base 121 are in a separated state, the electrolyte is injected through the second through hole 123 . At this time, the second through hole 123 serves as a liquid injection hole. For example, when the battery cover plate 1 is applied to a battery, the cap 122 is not covered on the second through hole 123 , and electrolyte is injected into the battery through the second through hole 123 . After the electrolyte is injected into the battery through the second through hole 123, the cap 122 is assembled with the base 121 through the second through hole 123 to seal the battery. to seal the battery.

When the cap 122 and the base 121 are in an assembled state, the cap 122 and the base 121 constitute the metal terminal 12 . The metal terminals 12 may all be located in the first through holes 111 , or may be partially located in the first through holes 111 . The metal terminal 12 serves as the lead-out terminal of the battery electrode.

In an optional embodiment, two first through holes 111 may be formed on the cover plate 11, and the two first through holes 111 are arranged at intervals; the battery cover plate includes two metal terminals 12, and the two metal terminals 12 are respectively is located in the first through hole 111 . At this time, the battery cover plate 1 can be used for batteries whose positive and negative electrodes are located on the same side. In one embodiment, the material of the cap 122 and the material of the base 121 may both be made of metal, or one of them may be made of metal, and the other may be made of rubber.

Thus, the battery cover plate 1 according to the embodiment of the present disclosure includes the cover plate 11 , the insulating member 13 , the base 121 and the cap 122 . The base 121 and the cap 122 are detachably connected, and the electrolyte is injected through the second through hole 123 on the base 121 when the cap 122 and the base 121 are not assembled. Compared with the prior art, the battery cover plate 1 of this example does not need to be provided with a separate injection hole, and the base 121 and the cap 122 as the electrode lead-out end are connected in a detachable connection manner. When the cap 122 and the base 121 are not assembled, The electrolyte is injected through the second through holes 123 on the base 121 . The battery cover plate 1 provided by the embodiment of the present disclosure has a simple structure and is easy to assemble. The battery cover plate 1 of this example does not need to separately open through holes on the cover plate 11 as liquid injection holes, which improves the strength of the battery cover plate 1 .

In an optional embodiment, a connecting portion is provided between the base 121 and the cap 122 .

For example, the base 121 and the cap 122 are detachably connected through the connecting portion. In one example, the cap 122 can be assembled with the base 121 through the connecting portion to form a metal terminal 12, and the metal terminal 12 can be used as a lead-out end of the battery electrode. For example, the cap 122 can be detached from the base 121 through the connecting portion, and the electrolyte is injected into the battery through the second through hole 123 .

In an optional embodiment, as shown in FIG. 1 and FIG. 5 , an inner thread is formed on the inner wall of the second through hole 123 , an outer thread is formed on at least a part of the outer wall of the cap 122 , and the base 121 and the cap 122 are screwed together.

In this embodiment, the base 121 and the cap 122 are detachably connected through screw connection. Further, in order to strengthen the sealing between the base 121 and the cap 122 , sealant is applied on the external thread formed on the outer wall of the base 121 , and/or the internal thread formed on the inner wall of the second through hole 123 Apply sealant.

Specifically, in this embodiment, the second through hole 123 is a threaded hole, and the base 121 and the cap 122 are injected with electrolyte through the threaded hole before the assembly is completed. After the electrolyte is injected through the threaded hole, the cap 122 is threadedly connected to the base 121 . In this example, the connecting portion includes an internal thread and an external thread.

In an optional embodiment, the connecting portion may also be a magnetic component. For example, a first magnetic component is provided on the inner wall of the second through hole 123, and a second magnetic component is provided on the outer wall of the cover cap 122, and the base 121 and the cover cap 122 are detachable through the first magnetic component and the second magnetic component. connect.

In an optional embodiment, as shown in FIG. 8 , the cap 122 is embedded in the second through hole 123 , and a sealing film 124 is disposed between the cap 122 and the base 121 .

In one embodiment, the second through hole 123 is a stepped hole, the stepped hole includes a first hole and a second hole communicating with the first hole, and the radial dimension of the first hole is larger than the radial dimension of the second hole size, the cap is secured in the first hole. Specifically, the second through hole 123 is sealed through the cap 122 by means of heat sealing. For example, a sealing film 124 can be used for heat sealing at the step, and the second through hole 123 is blocked by the cap 122 .

In another embodiment, the base 121 and the cap 122 are connected through an interference fit. Specifically, a sealing film is provided on the inner peripheral surface of the second through hole 123 , the cap 122 is embedded in the second through hole 123 , and the sealing film 124 is located between the cap 122 and the base 121 at this time. Wherein, a sealing film is provided at the connection between the cap 122 and the base 121 , which improves the sealing performance of the cap 122 and the base 121 . On the other hand, a sealing film is provided at the connection between the cap 122 and the base 121 to improve the connection strength of the cap 122 and the base 121 .

In a specific embodiment, the sealing film 124 is a PP composite film. At least the contact portion of the base 121 and the cap 122 is sealed with a PP composite film.

The base 121 and the cap 122 are detachably sealed. When the base 121 and the cap 122 are in a separated state, the electrolyte is injected through the second through hole 123 . When the base 121 and the cap 122 are in an assembled state, the base 121 and the cap 122 are sealedly connected.

It should be noted that the detachable connection method between the base 121 and the cap includes, but is not limited to, screw connection, thermocompression connection, or interference fit connection.

Optionally, as shown in FIG. 1 , FIG. 5 and FIG. 8 , the insulating member 13 is provided on the inner peripheral surface of the first through hole 111 , and at least one of the two ends of the insulating member 13 is along the The first through hole 111 extends radially outward and covers a surface of the cover plate 11 .

In one example, the insulating member 13 is disposed on the inner peripheral surface of the first through hole 111 , and the insulating member 13 includes opposite ends. The opposite ends include an upper end and a lower end. At least one of the upper end and the lower end extends outward along the radial direction of the first through hole 111 and covers a surface of the cover plate.

In one embodiment, as shown in FIG. 1 , the insulating member 13 is provided on the inner peripheral surface of the first through hole 111 , and both ends of the insulating member 13 extend outward along the radial direction of the first through hole 111 respectively and cover the cover The upper and lower surfaces of the board 11 .

For example, in FIG. 1 , the base 121 includes a first base and a second base connected to the first base. The first base is a cylindrical structure. The second base is located at the lower end of the first base and extends out of the first through hole 111 . The second base extends outward along the radial direction of the first through hole 111 to cover the outer surface of the insulating member 13 and does not exceed the edge of the insulating member 13 . For example, the first base and the second base are integrally formed to form the base 121 .

The cap 122 includes a first cap body and a second cap body connected with the first cap body. The first cap body is a cylindrical structure, and the first cap body is connected to the base 121 through the second through hole 123 . The second cap body is located on the upper side of the first cap body and extends out of the first through hole 111 . The second cap body extends outward along the radial direction of the first through hole 111 to cover the outer surface of the insulating member 13 and does not exceed the edge of the insulating member 13 . For example, the first cap body and the second cap body are integrally formed to form the cap 122 .

In yet another embodiment, as shown in FIGS. 3 and 6 , the insulating member 13 is provided on the inner peripheral surface of the first through hole 111 , and the upper end of the insulating member 13 extends outward along the radial direction of the first through hole 111 and Cover the upper surface of the cover plate 11 .

For example, in FIG. 8 , the base 121 includes a first base and a second base connected to the first base. The first base is a cylindrical structure, the lower end of the first base protrudes out of the first through hole 111 by a predetermined distance, and the lower end of the first base is used for connecting with the tab. Since the lower end of the first base extends out of the first through hole 111 , and the lower end of the first base extending out of the first through hole 111 is connected to the tab, there is a predetermined gap between the tab drawn from the cell and the cover plate 11 . The predetermined distance between the two can prevent the tabs from contacting the cover plate 11 . Therefore, the lower surface of the cover plate 11 in this example is not covered with an insulating member.

The second base of the base 121 is located at the upper end of the first base, the second base extends along the radial direction of the first through hole 111 and covers a part of the outer surface of the insulating member 13 and does not exceed the edge of the insulating member 13 .

The first base and the second base of the base 121 are both provided with through holes, wherein the through hole opened on the first base communicates with the through hole opened on the second base to form a second through hole 123 . In this embodiment, the second through holes 123 are stepped holes. The cap 122 is covered on the stepped hole, wherein the upper surface of the cap 122 is flush with the upper surface of the second base. In this embodiment, the cap 122 is a columnar structure.

In an optional embodiment, as shown in FIG. 5 , along the axial direction of the first through hole 111 , the insulating member 13 further includes an insulating support arm 131 , and the cover plate 11 is along the thickness direction of the cover plate 11 . An accommodating groove is formed, and the insulating support arm 131 is embedded in the accommodating groove.

For example, an insulating support arm 131 is provided on the insulating member 13, and the insulating support arm 131 is connected with the cover plate 11, which improves the connection area between the insulating member 13 and the cover plate 11, thereby enhancing the connection strength between the insulating member 13 and the cover plate 11. . In one embodiment, the disposing direction of the insulating support arm 131 is perpendicular to the extending direction of the insulating member 13 .

In an optional embodiment, as shown in FIGS. 1 , 5 and 8 , the base 121 includes a first base 1211 and a second base 1212 connected to the first base 1211 . The first base 1211 is connected to the cover plate 11 , and the second base 1212 penetrates through the first through hole 111 . For example, the radial dimension of the first base 1211 is larger than the radial dimension of the second base 1212 , the first base 1211 can be connected to the upper surface of the cover plate 11 , and the first base 1211 and the upper surface of the cover plate 11 are An insulating member 13 is arranged between them. This example improves the connection reliability between the base 121 and the cover 11 .

In one embodiment, as shown in FIGS. 5 and 7 , a first connecting surface is formed on the side of the first base 1211 close to the second base 1212 , and the second base 1212 is close to the first base 1212 . A second connecting surface is formed on one side of the base 1211 , and the first connecting surface and the second connecting surface are oppositely disposed and connected.

Along the radial direction of the first through hole 111 , the size of the first connection surface is larger than the size of the second connection surface, and the first connection surface is disposed above the pole tab 31 for connecting with the pole. The ears 31 are electrically connected.

Specifically, as shown in FIG. 3 and FIG. 5 , the first base 1211 and the second base 1212 are formed by integral molding. The first base 1211 and the second base 1212 respectively define through holes, and the through holes opened on the first base 1211 and the through holes opened on the second base 1212 communicate with each other to form a second through hole 123 .

The first base 1211 has a T-shaped structure, the lower end of the first base 1211 protrudes out of the first through hole 111 , and the lower end of the first base 1211 protrudes by a predetermined distance.

The second base 1212 has a trapezoidal structure, wherein the length of the upper base of the second base 1212 is greater than the length of the lower base of the second base 1212 .

The first connection surface formed at the lower end of the first base 1211 is connected to the second connection surface formed at the upper bottom of the second base 1212 . Since the size of the first connecting surface is larger than the size of the second connecting surface along the radial direction of the first through hole 111 , after the first base 1211 and the second base 1212 are connected, the In the radial direction of the through hole 111 , the first connection surface is formed with an extension surface relative to the second connection surface.

When the battery cover plate 1 is applied to a battery, the battery includes a casing 2 and a battery cell 3 disposed inside the casing 2 . The battery core 3 leads out the tab 31 , and the extension surface is located above the tab 31 and is electrically connected to the tab 31 , for example, the extension surface is welded with the tab 31 . Because the extension surface is pressed above the tabs 31, the displacement of the tabs 31 along the height direction of the battery is restricted, the tabs 31 are prevented from contacting with the cover plate 11, and the short-circuit phenomenon of the battery is prevented.

In an optional embodiment, as shown in FIG. 5 , the insulating member 13 is provided on the inner peripheral surface of the first through hole 111 , and the upper end of the insulating member 13 is along the length of the first through hole 111 . It extends radially outward and covers the outer surface of the cover plate 11 .

Due to the specific structural design of the base 121, the first connecting surface formed at the lower end of the first base 1211 of the base 121 can be pressed on the tab 31, which limits the displacement of the tab 31 along the height direction of the battery and avoids the tab 31 is in contact with the cover plate 11, thereby preventing the short circuit of the battery.

Therefore, in this example, the insulating member 13 is provided on the inner peripheral surface of the first through hole 111 , and the insulating member 13 includes an upper end and a lower end that are arranged opposite to each other, and only the upper end of the insulating member 13 needs to be along the radial direction of the first through hole 111 . It extends and covers the outer surface of the cover plate, so as to avoid the battery short circuit caused by the direct contact between the base 121 and the cover plate 11 .

In an optional embodiment, the cover plate 11 , the base 121 and the insulating member 13 are integrally formed.

For example, the cover plate 11 , the base 121 and the insulating member 13 are integrally formed by injection molding. The cover plate 11, the base 121 and the insulating member 13 are integral structural members. The assembly process of the battery cover plate 1 in this example is simple and convenient for users to operate. In an example, when the battery cover 1 is applied to a battery, the integrated structure composed of the cover 11 , the base 121 and the insulating member 13 is first connected to the battery case 2 . Then, the electrolyte is injected through the second through holes 123 formed on the base 121 . Finally, the cap 122 is set on the second through hole 123 to seal the battery.

In an optional embodiment, the material of the base 121 is the same as the material of the cap 122 .

For example, both the base 121 and the cap 122 can be made of aluminum. The material of the base 121 is the same as the material of the cap 122, and the base 121 and the cap 122 can be used as the same electrode to lead out the battery current. For example, the base 121 and the cap 122 can both act as positive electrodes to draw battery current. For example, the battery cover plate 1 is applied to the battery, and the positive electrode ear of the battery cell 3 is welded to the base 121 or the positive electrode ear of the battery cell 3 is welded to the cap 122 .

According to one embodiment of the present disclosure, a battery is provided. Referring to FIGS. 1-9 , the housing 2 and the battery cover 1 described in the first aspect are included. An opening is formed on one side of the casing 2 , the battery cover plate 1 covers the opening, and the cover plate 11 is welded to the casing 2 .

For example, the housing 2 includes side walls, the side walls are enclosed in the circumferential direction of the housing 2 , and the side walls are enclosed in a cylindrical shape or in a cubic structure. At least one end of the casing 2 forms an opening, and the battery cover 1 closes the opening.

In a specific embodiment, the housing 2 includes a side wall and a bottom wall, wherein the side wall and the bottom wall are integrally formed. The end of the casing 2 opposite to the bottom wall forms an opening, and the battery cover plate 1 closes the opening.

The cover plate 11 and the casing 2 can be connected by laser welding or resistance welding.

In an optional embodiment, the material of the cover plate 11 is the same as the material of the casing 2 .

For example, the cover plate 11 and the case 2 are made of steel, the cover plate 11 and the case 2 can be used as the lead end of the same electrode of the battery, and the base 121 and the cap 122 can be used as the lead end of the other electrode of the battery. For example, the battery cell 3 includes a positive electrode lug and a negative electrode lug, wherein the positive electrode lug is electrically connected to the base 121 or the cap 122, and the negative electrode lug is electrically connected to the shell cover 11 or the casing 2 to ensure normal use of the battery.

In an optional embodiment, as shown in FIG. 5 , in a state where the battery cover 1 covers the opening, at least a part of the base 121 extends into the interior of the casing 2 .

For example, the base 121 includes a first base 1211 and a second base 1212 , wherein the second base 1212 extends to the inside of the casing 2 , which further improves the sealing between the battery cover 1 and the casing 2 .

According to an embodiment of the present disclosure, a method for preparing a battery is provided, and the method includes the following steps:

A casing 2 is provided, and the battery core 3 is arranged in the casing 2;

The battery cover 1 is provided, the cover 11 is welded with the casing 2 and the base 121 and the cover 11 are isolated by the insulating member 13;

The electrolyte is injected into the casing 2 through the second through hole 123 on the base 121;

The cap 122 is disposed in the second through hole 123 to seal the battery.

Specifically, a casing 2 is provided, and the material of the casing 2 can be made of steel. The housing 2 is formed with an accommodating cavity, and the battery cells 3 are located in the accommodating cavity.

Weld the cover plate 11 to the housing 2 . A first through hole 111 is formed through the cover plate 11 along its thickness direction, and the base 121 is located in the first through hole 111 ; In a preferred embodiment, the cover plate 11 , the insulating member 13 and the base 121 are integrally formed to form an integral structural member. The one-piece structure is covered on the casing 2 .

Then, the electrolyte is injected into the casing 2 through the second through holes 123 formed on the base 121 .

Finally, the cap 122 is sealedly connected to the base 121 through the second through hole 123 .

Since the cap 122 and the base 121 are detachably connected, compared with the prior art, the battery cover plate 1 of this example does not need to separately open through holes on the cover plate 11 as liquid injection holes, which improves the strength of the battery cover plate 1 . On the other hand, the cover plate 11 and the base 121 are detachably connected, so that the electrolyte solution can be replenished into the casing 2 easily.

On the other hand, in this example, the cover plate 11 and the casing 2 are welded first, and then the electrolyte is injected into the casing 2 through the second through hole 123 formed on the base 121 . In the prior art, during the assembling process of the battery, the electrolyte solution is injected into the casing first, and then the battery cover plate and the casing are welded. Compared with the prior art, this example changes the assembly sequence of the battery, so as to avoid the high temperature generated during the welding of the casing and the cover plate from affecting the properties of the electrolyte injected first.

Optionally, before the step of injecting electrolyte into the casing 2 through the second through hole 123 on the base 121, the method further includes:

The positive tab of the battery cell 3 is welded to the base 121 , and the negative electrode tab of the battery cell 3 is welded to the cover plate 11 or the casing 2 .

Specifically, the battery cell 3 includes a positive electrode lug and a negative electrode lug. The base 121 serves as the lead-out end of the positive electrode, and the cover plate 11 or the case 2 serves as the lead-out end of the negative electrode. The positive terminal of the battery cell 3 can be welded to the base 121 , the negative terminal of the battery core 3 can be welded to the cover plate 11 or the casing 2 , and then the second pass through the base 121 The hole 123 injects the electrolyte into the casing 2 .

Weld the negative lug of the battery cell 3 to the cover plate 11 or the casing 2;

After the step of disposing the cap 122 in the second through hole 123 to seal the battery, the method further includes:

Weld the positive tab of the battery cell 3 to the cap 122 .

Specifically, the base 121 and the cap 122 draw current as the same pole of the battery. In this example, the cap 122 is welded to the positive lug of the battery cell 3 .

In this example, the battery cell 3 includes a positive electrode lug and a negative electrode lug. The cap 122 serves as the lead-out end of the positive electrode, and the cover plate 11 or the case 2 serves as the lead-out end of the negative electrode.

Before the step of injecting the electrolyte into the casing 2 through the second through hole 123 on the base 121 , the negative terminal of the battery cell 3 is welded to the cover plate 11 or the casing 2 .

After the step of disposing the cap 122 in the second through hole 123 to seal the battery, the positive tab of the battery cell 3 is welded to the cap 122 by a laser disposed outside the casing 2 .

While some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art will appreciate that the above examples are provided for illustration only, and are not intended to limit the scope of the present disclosure. Those skilled in the art will appreciate that modifications may be made to the above embodiments without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

A battery cover, characterized in that, comprising:

a cover plate, wherein the cover plate penetrates along the thickness direction to form a first through hole;

a base, at least a part of the base is located in the first through hole, an insulating member is arranged between the base and the cover plate; the base passes through the base along the thickness direction to form a second through hole;

a cap, at least a part of the cap is located in the second through hole and is detachably connected to the base, and when the cap is separated from the base, the second through hole is used as a liquid injection hole.
The battery cover according to claim 1, wherein a connecting portion is provided between the base and the cap.
The battery cover plate according to claim 1 or 2, wherein an inner thread is formed on an inner wall of the second through hole, an outer thread is formed on an outer wall of at least a part of the cap, and the base and the The caps are screwed together.
The battery cover plate according to claim 1, wherein the cap is embedded in the second through hole, and a sealing film is provided between the cap and the base.
The battery cover plate according to claim 1, wherein the insulating member is provided on the inner peripheral surface of the first through hole, and at least one of the two ends of the insulating member is along the first through hole. The holes extend radially outward and cover the surface of the cover plate.
The battery cover plate according to claim 5, wherein, along the axial direction of the first through hole, the insulating member further comprises an insulating support arm;

An accommodating groove is formed along the thickness direction of the cover plate, and the insulating support arm is embedded in the accommodating groove.
The battery cover according to claim 1, wherein the base comprises a first base and a second base connected to the first base;

The first base is connected to the cover plate, and the second base penetrates the first through hole.
The battery cover plate according to claim 7, wherein a first connecting surface is formed on a side of the first base close to the second base, and the second base is close to the first base A second connection surface is formed on one side, and the first connection surface and the second connection surface are oppositely arranged and connected;

Along the radial direction of the first through hole, the size of the first connection surface is larger than the size of the second connection surface, and the first connection surface is arranged above the tab for electrically connecting with the tab. connect.
The battery cover plate according to claim 8, wherein the insulating member is disposed on the inner peripheral surface of the first through hole, and the upper end of the insulating member extends toward the radial direction of the first through hole. Outwardly extends and covers the outer surface of the cover plate.
The battery cover plate according to claim 1, wherein the cover plate, the base and the insulating member are integrally formed.
A battery, characterized in that it comprises a casing and the battery cover plate according to any one of claims 1-10;

An opening is formed on one side of the casing, the battery cover plate covers the opening, and the cover plate is welded with the casing.
The battery according to claim 11, wherein at least a part of the base extends into the casing when the battery cover covers the opening.
A preparation method of a battery, characterized in that the method comprises the steps:

A casing is provided, and the battery core is arranged in the casing;

A battery cover is provided, the cover is welded with the casing, and the base is isolated from the cover by an insulating member;

The electrolyte is injected into the casing through the second through hole on the base;

A cap is arranged in the second through hole to seal the battery.
The method according to claim 13, wherein before the step of injecting electrolyte into the casing through the second through hole on the base, the method further comprises:

The positive ear of the battery cell is welded to the base, and the negative electrode ear of the battery core is welded to the cover plate or the casing.
The method according to claim 13, wherein before the step of injecting electrolyte into the casing through the second through hole on the base, the method further comprises:

Weld the negative lug of the battery cell with the cover plate or the shell;

After the step of disposing the cap in the second through hole to seal the battery, the method further includes: welding the positive electrode ear of the battery cell to the cap.