Battery cell cover plate, battery cell, and battery pack

Abstract

A battery cell cover plate, a battery cell, and a battery pack. The battery cell cover plate comprises a cover plate body (1), and an explosion-proof valve (2) and an energy absorption part which are disposed on the cover plate body (1); the energy absorption part and the explosion-proof valve (2) are spaced apart from each other, and the energy absorption part is used for dissipating the stress at the explosion-proof valve (2). According to the battery cell cover plate, the energy absorption part is disposed on the cover plate body (1), to absorb and dissipate the stress at the explosion-proof valve (2) when a battery cell deforms abnormally due to pressing, vibration or another condition, thereby avoiding cracking of the explosion-proof valve (2) due to stress concentration so that the explosion-proof valve (2) has better reliability, and reducing the risk of liquid leakage of the battery cell due to cracking of the explosion-proof valve (2) to the maximum extent.

Description

Battery cover, battery cell and battery pack

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application with application number CN202322557196.1 and title “Battery cell cover, battery cell and battery pack” filed with the Patent Office of China on September 19, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the technical field of lithium battery manufacturing, and in particular to a battery cell cover plate. It also relates to a battery cell provided with the battery cover plate, and a battery pack having the battery cell. Background Art

[0004] The battery pack of a new energy vehicle typically consists of several cells, each of which has at least one cover (also called a cover plate or end cap) to protect the electrolyte inside the cell from leaking. Specifically, if the chemical reaction within the cell is not functioning properly, such as in the event of overcharging or discharging, or excessive temperature, extreme pressure will be generated within the battery pack, which can easily lead to battery explosion.

[0005] To prevent this situation from occurring, battery packs usually solve this problem by adding an explosion-proof valve on the top cover. The explosion-proof valve can reduce the risk of battery explosion during use by controlling the pressure threshold generated by the battery cell during charging or discharging. For example, when the internal pressure is too high, the explosion-proof valve will automatically pop out to release the internal pressure of the battery cell to prevent an explosion.

[0006] However, existing battery cell explosion-proof valves are prone to cracking due to stress concentration when subjected to large forces, such as vibration, impact, and expansion force. This can cause the explosion-proof valve to open prematurely and fail, ultimately causing the battery cell to leak and reducing product safety quality.

[0007] Application Contents

[0008] In view of this, the present application proposes a battery cell cover that can reduce the risk of cracking and leakage of the explosion-proof valve.

[0009] In a first aspect, the present application provides a battery cell cover, comprising a cover body, and an explosion-proof valve and an energy-absorbing portion provided on the cover body;

[0010] The energy absorbing portion is spaced apart from the explosion-proof valve, and is used to dissipate stress at the explosion-proof valve.

[0011] Beneficial effect: By arranging an energy-absorbing part on the cover body, when the battery cell is abnormally deformed due to extrusion or vibration, the energy-absorbing part can absorb and dissipate the stress at the explosion-proof valve, thereby avoiding the explosion-proof valve from cracking due to stress concentration, making the explosion-proof valve more reliable, and thus minimizing the risk of leakage of the battery cell due to cracking of the explosion-proof valve.

[0012] In an optional embodiment, the energy absorbing portion includes an energy absorbing groove spaced apart from the explosion-proof valve, and the energy absorbing groove extends along the width direction of the cover plate body.

[0013] In an optional embodiment, the cross-section of the energy absorption groove is rectangular or V-shaped.

[0014] Beneficial effects: an energy-absorbing groove extending along the width direction of the cover plate body is provided, and the cross section of the energy-absorbing groove is rectangular or V-shaped, which has a simple structure and is convenient for manufacture and arrangement.

[0015] In an optional embodiment, in the length direction of the cover body, the ratio of the spacing dimension between the energy absorption groove and the explosion-proof valve to the thickness dimension of the cover body is between 1:1 and 2; in the width direction of the cover body, the ratio of the spacing dimension between the energy absorption groove and any edge of the cover body to the thickness dimension of the cover body is between 1:1 and 2.

[0016] In an optional embodiment, in the length direction of the cover body, the width dimension of the opening of the energy absorption groove is 1 / 2 of the distance dimension between the energy absorption groove and the explosion-proof valve; in the thickness direction of the cover body, the depth dimension of the energy absorption groove is 1 / 4 of the distance dimension between the energy absorption groove and the explosion-proof valve.

[0017] Beneficial effect: The groove range and groove size of the energy absorption groove can be controlled within a reasonable range, so that the battery cover can reduce the stress on the explosion-proof valve and the risk of cracking of the explosion-proof valve without affecting the normal pop-up of the explosion-proof valve when the internal pressure of the battery cell is too high, thereby making the battery cell more reliable in installation and use.

[0018] In an optional embodiment, there are two energy absorption grooves; in the length direction of the cover plate body, the two energy absorption grooves are respectively located on both sides of the explosion-proof valve.

[0019] Beneficial effect: Energy absorption grooves are provided on both sides of the explosion-proof valve in the length direction of the cover body, which is conducive to the consistent energy absorption effect on both sides of the explosion-proof valve, and avoids the explosion-proof valve from failing due to uneven force on both sides when the pressure inside the battery cell is too high.

[0020] In an optional embodiment, the energy absorbing portion is provided on the outer side of the cover plate body, and a reinforcing rib is provided on the inner side of the cover plate body, and the reinforcing rib is provided close to the energy absorbing portion.

[0021] Beneficial effect: The setting of the reinforcing ribs ensures the strength of the battery cover while being able to absorb the abnormal deformation of the explosion-proof valve.

[0022] In an optional embodiment, the reinforcing rib is formed by protruding from the inner side wall of the cover body, and the ratio of the protruding size of the reinforcing rib to the depth size of the energy absorption groove is between 1:1 and 2; and / or, in the thickness direction of the cover body, the reinforcing rib is arranged opposite to the energy absorption part.

[0023] Beneficial effect: The reinforcement ribs are arranged corresponding to the energy absorbing portion, and the ratio of the protruding size thereof to the depth size of the energy absorbing groove is between 1:1 and 2, which can enhance the structural reinforcement effect of the cover plate body.

[0024] In a second aspect, the present application provides a battery cell, in which the battery cell cover as described above is provided.

[0025] In a third aspect, the present application provides a battery pack comprising the above-mentioned battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0027] FIG1 is a schematic diagram of the overall structure of a cell cover according to an embodiment of the present application;

[0028] Figure 2 is an enlarged view of point A in Figure 1;

[0029] FIG3 is a cross-sectional view taken along line BB in FIG1 ;

[0030] FIG4 is an enlarged view of point C in FIG3 ;

[0031] FIG5 is a schematic structural diagram of a V-shaped energy absorption groove according to an embodiment of the present application;

[0032] Explanation of the accompanying symbols: 1. Cover plate body; 2. Explosion-proof valve; 3. Energy absorption groove; 4. Reinforcement rib. DETAILED DESCRIPTION

[0033] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0034] Example 1

[0035] This embodiment relates to a battery cell cover plate, which can absorb and dissipate the stress at the explosion-proof valve 2 when the battery cell is abnormally deformed due to extrusion or vibration, thereby preventing the explosion-proof valve 2 from cracking due to stress concentration, thereby minimizing the risk of battery cell leakage due to cracking of the explosion-proof valve 2.

[0036] As shown in Figure 1, the cell cover of this embodiment includes a cover body 1, an explosion-proof valve 2, and an energy-absorbing portion disposed on the cover body 1. The energy-absorbing portion is spaced apart from the explosion-proof valve 2 and is used to dissipate stress at the explosion-proof valve 2.

[0037] Specifically, in this embodiment, as an exemplary structure, still as shown in Figure 1 , the energy absorbing portion includes an energy absorbing groove 3 spaced apart from the explosion-proof valve 2 . The groove 3 extends along the width of the cover plate body 1 (the width direction shown in Figure 1 ). Furthermore, the cross-section of the groove 3 is preferably rectangular or V-shaped. This results in a simple structure, facilitating fabrication and deployment.

[0038] Here, when the cross section of the energy absorbing groove 3 is set to be V-shaped, compared with a rectangular shape, it can not only absorb the abnormal deformation of the explosion-proof valve, but also reduce the processing process.

[0039] Taking into account the structural strength requirements of the cover body 1, in this embodiment, as shown in Figure 2, as a preferred implementation form, in the length direction of the cover body 1 (the length direction shown in Figure 1), the ratio of the spacing dimension D1 between the energy absorption groove 3 and the explosion-proof valve 2 to the thickness dimension D3 of the cover body 1 is between 1:1 and 2, specifically 1:1, 1:1.5 or 1:2.

[0040] At the same time, in the width direction of the cover body 1, the ratio of the spacing dimension D2 between the energy absorption groove 3 and any edge of the cover body 1 to the thickness dimension D3 of the cover body 1 is between 1:1 and 2, specifically 1:1, 1:1.5 or 1:2.

[0041] Furthermore, as a preferred embodiment, as shown in conjunction with FIG2 and FIG4 , in this embodiment, the width dimension b of the opening of the energy-absorbing groove 3 in the length direction of the cover body 1 is 1 / 2 of the distance dimension D1 between the energy-absorbing groove 3 and the explosion-proof valve 2. In the thickness direction of the cover body 1, the depth dimension c of the energy-absorbing groove 3 is 1 / 4 of the distance dimension D1 between the energy-absorbing groove 3 and the explosion-proof valve 2.

[0042] The advantage of such a setting is that the groove range and groove size of the energy absorption groove 3 can be controlled within a reasonable range, so that the battery cell cover can reduce the stress on the explosion-proof valve 2 and reduce the risk of cracking of the explosion-proof valve 2 without affecting the normal pop-up of the explosion-proof valve 2 when the internal pressure of the battery cell is too high, so that the battery cell has better installation and use reliability.

[0043] It can be understood that in this embodiment, since the spacing dimension D2 between the energy absorption groove 3 and the two edges of the cover body 1 in the width direction of the cover body 1 is the same as the ratio of the thickness dimension D3 of the cover body 1, the length dimension a of the energy absorption groove 3 is equal to the difference between the width dimension of the battery cell cover and 2*D2.

[0044] In addition, in this embodiment, as a preferred implementation form, there are two energy absorption grooves 3, and in the length direction of the cover body 1, the two energy absorption grooves 3 are respectively located on both sides of the explosion-proof valve 2. This can facilitate the energy absorption effect on both sides of the explosion-proof valve 2 to be consistent, and avoid the explosion-proof valve 2 from failing when the pressure inside the battery cell is too high due to uneven force on both sides.

[0045] In addition, in this embodiment, as a preferred implementation, as shown in Figure 3, the energy-absorbing portion is disposed on the outside of the cover body 1, and reinforcing ribs 4 are provided on the inside of the cover body 1, located close to the energy-absorbing portion. The provision of reinforcing ribs 4 ensures the strength of the cell cover while allowing the energy-absorbing portion to absorb abnormal deformation of the explosion-proof valve 2.

[0046] Furthermore, in this embodiment, as a preferred implementation form, as still shown in Figure 4, in the thickness direction of the cover body 1, the reinforcing rib 4 is arranged opposite the energy absorbing part. At the same time, as a preferred implementation form, the reinforcing rib 4 is formed by the protrusion of the inner wall of the cover body 1, and the ratio of the height dimension of the reinforcing rib 4 to the depth dimension c of the energy absorbing groove 3 is between 1:1 and 2, specifically 1:1, 1:1.5 or 1:2.

[0047] It is understandable that the arrangement of the reinforcing rib 4 corresponding to the energy absorbing portion and the ratio of its protruding dimension d to the depth dimension c of the energy absorbing groove 3 being between 1:1 and 2 can both enhance the structural reinforcement effect of the cover plate body 1 .

[0048] The battery cell cover of this embodiment, by providing an energy-absorbing portion on the cover body 1, can absorb and dissipate the stress at the explosion-proof valve 2 when the battery cell is abnormally deformed due to extrusion or vibration, thereby avoiding the explosion-proof valve 2 from cracking due to stress concentration, making the explosion-proof valve 2 more reliable, and thus minimizing the risk of battery cell leakage due to cracking of the explosion-proof valve 2.

[0049] Example 2

[0050] This embodiment relates to a battery cell, in which the battery cell cover plate of the first embodiment is provided. This embodiment also relates to a battery pack provided with the battery cell.

[0051] The battery cell and battery pack of this embodiment, by providing the battery cell cover plate of the first embodiment, can reduce the risk of leakage of the battery cell due to cracking of the explosion-proof valve 2 and have better safety.

[0052] Although the embodiments of the present application have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations shall fall within the scope defined by the appended claims. Industrial Applicability

[0053] By providing an energy-absorbing portion on the cover body, when the battery cell is abnormally deformed due to extrusion or vibration, the energy-absorbing portion can absorb and dissipate the stress at the explosion-proof valve, thereby preventing the explosion-proof valve from cracking due to stress concentration. This makes the explosion-proof valve more reliable, thereby minimizing the risk of leakage of the battery cell due to cracking of the explosion-proof valve.

Claims

1. A battery cover, characterized in that: It comprises a cover plate body, and an explosion-proof valve and an energy absorbing part arranged on the cover plate body; The energy absorbing part is spaced apart from the explosion-proof valve, and the energy absorbing part is used to dissipate stress at the explosion-proof valve.

2. The cell cover according to claim 1, characterized in that: The energy absorbing portion includes an energy absorbing groove spaced apart from the explosion-proof valve, and the energy absorbing groove is extended along the width direction of the cover plate body.

3. The cell cover plate according to claim 2, characterized in that: The cross section of the energy absorbing groove is rectangular or V-shaped.

4. The cell cover plate according to claim 3, characterized in that: In the length direction of the cover plate body, the ratio of the spacing dimension between the energy absorbing groove and the explosion-proof valve to the thickness dimension of the cover plate body is between 1:1 and 2; In the width direction of the cover plate body, the ratio of the spacing dimension between the energy absorbing groove and any edge of the cover plate body to the thickness dimension of the cover plate body is between 1:1 and 2.

5. The cell cover plate according to claim 4, characterized in that: In the length direction of the cover plate body, the width dimension of the opening of the energy absorption groove is 1 / 2 of the distance dimension between the energy absorption groove and the explosion-proof valve; In the thickness direction of the cover plate body, the depth dimension of the energy absorption groove is 1 / 4 of the distance dimension between the energy absorption groove and the explosion-proof valve.

6. The cell cover plate according to claim 2, characterized in that: There are two energy absorption grooves; In the length direction of the cover plate body, the two energy absorbing grooves are respectively located on both sides of the explosion-proof valve.

7. The cell cover according to any one of claims 2 to 6, characterized in that: The energy absorbing part is arranged on the outer side of the cover plate body, and a reinforcing rib is arranged on the inner side of the cover plate body, and the reinforcing rib is arranged close to the energy absorbing part.

8. The cell cover plate according to claim 7, characterized in that: The reinforcing rib is formed by protruding from the inner side wall of the battery cover, and the ratio of the protruding dimension of the reinforcing rib to the depth dimension of the energy absorption groove is between 1:1 and 2; and / or, In the thickness direction of the cover plate body, the reinforcing rib is arranged opposite to the energy absorbing portion.

9. A battery cell, characterized in that: The battery cell is provided with a battery cell cover according to any one of claims 1 to 8.

10. A battery pack, characterized in that: Comprising the battery cell as claimed in claim 9.

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