Battery case and battery cell

Abstract

The invention belongs to the technical field of batteries, and discloses a battery shell and a single battery, the battery shell comprises a first wall body and a second wall body, the first wall body is provided with an explosion-proof hole, the explosion-proof hole is located in the middle of the first wall body in a first direction, the thickness of the first wall body is T1, the second wall body is adjacent to the first wall body, and the thickness of the second wall body is T1. The edge, connected with the first wall body, of the second wall body extends in the first direction, a first convex rib is arranged on the inner wall of the second wall body, extends in the first direction and is located in the middle of the second wall body in the first direction, the distance between the side, facing the first wall body, of the first convex rib and the inner wall of the first wall body is W, W / T1 is smaller than or equal to 10, and W is larger than or equal to 10. When the anti-explosion hole is punched in the first wall body and the anti-explosion valve is welded to the anti-explosion hole, the probability that the area, close to the anti-explosion hole, of the second wall body deforms is low.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a battery case and a battery cell. Background Art

[0002] The battery case is a basic component of the battery and is a carrier for accommodating the electrode group and assembling structures such as a battery cover plate, electrode posts, and explosion-proof valves. Therefore, the battery case needs to have a certain strength and stiffness. In the existing battery field, in order to pursue the lightweight of the battery, the battery case is generally thin, which can reduce the weight of the battery.

[0003] However, the thinner battery case sacrifices stiffness, resulting in the easy deformation of the battery case. Especially when punching an explosion-proof hole on the wall of the battery case (hereinafter, the wall with the punched explosion-proof hole is simply referred to as the explosion-proof wall), the adjacent wall (hereinafter, this wall is simply referred to as the adjacent wall) adjacent to the explosion-proof wall is prone to concave deformation, thereby reducing the dimensional accuracy of the punching; after welding the explosion-proof valve at the explosion-proof hole with low dimensional accuracy, there is likely to be a gap between the edge of the explosion-proof valve and the edge of the explosion-proof hole, reducing the sealing performance between the explosion-proof valve and the explosion-proof wall (i.e., reducing the welding yield of the explosion-proof valve); in addition, when welding the explosion-proof valve at the explosion-proof hole, the adjacent wall is prone to thermoplastic deformation, and the deformed adjacent wall applies stress to the explosion-proof wall, causing the edge of the explosion-proof hole to deform, further reducing the dimensional accuracy of the explosion-proof hole and expanding the gap between the edge of the explosion-proof valve and the edge of the explosion-proof hole, further reducing the sealing performance between the explosion-proof valve and the explosion-proof wall.

[0004] Therefore, it is urgent to propose a battery case and a battery cell to solve the above technical problems. Summary of the Invention

[0005] The first object of the present invention is to provide a battery case that can improve the structural strength of the area of the second wall adjacent to the explosion-proof hole, and thus, when punching the explosion-proof hole on the first wall and welding the explosion-proof valve to the explosion-proof hole, the probability of deformation of the area of the second wall adjacent to the explosion-proof hole can be reduced.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] A battery case, comprising:

[0008] A first wall, on which an explosion-proof hole is provided. The explosion-proof hole is located in the middle of the first wall in the first direction, and the thickness of the first wall is T1;

[0009] The second wall body is disposed adjacent to the first wall body. The edge of the second wall body connected to the first wall body extends in the first direction. A first rib is provided on the inner wall of the second wall body. The first rib extends in the first direction and is located in the middle of the second wall body in the first direction. The distance between the side of the first rib facing the first wall body and the inner wall of the first wall body is W, and W / T1 ≤ 10.

[0010] Optionally, W / T1 > 3.3.

[0011] Optionally, the thickness of the first wall body is greater than the thickness of the second wall body.

[0012] Optionally, the thickness of the second wall body is T2, and the thickness of the first rib protruding from the inner wall of the second wall body is H2, (T2 + H2) / T2 ≥ 1.3.

[0013] Optionally, (T2 + H2) / T2 < 1.6.

[0014] Optionally, a convex rib structure is provided on the first wall body. The convex rib structure is located at the edge of the explosion-proof hole and at least partially on the side of the explosion-proof hole facing the second wall body.

[0015] Optionally, the convex rib structure surrounds the explosion-proof hole and forms a limiting area on the outer periphery of the explosion-proof hole. The limiting area is used to limit the position of the stamping positioning block.

[0016] Optionally, the number of the first wall bodies and the second wall bodies is two each. The two first wall bodies are disposed opposite to each other in the third direction. The two second wall bodies are disposed opposite to each other in the second direction. The first direction, the second direction, and the third direction are perpendicular to each other in pairs. Each end of each second wall body in the third direction is connected to a first wall body. Two first ribs are provided on each second wall body. The two first ribs on the same second wall body are respectively arranged in groups with a first wall body. In the third direction, the distance between the side of the first rib in the same group facing the first wall body and the inner wall of the first wall body is W.

[0017] Optionally, a second rib is further provided on the second wall body.

[0018] The second object of the present invention is to provide a battery cell, which can improve the welding yield of the explosion-proof valve.

[0019] To achieve this purpose, the present invention adopts the following technical solutions:

[0020] The battery cell includes a pole group and the above-mentioned battery case. The housing mechanism is provided with a receiving cavity, and the pole group is arranged in the receiving cavity.

[0021] The beneficial effects of the present invention:

[0022] The battery case provided by the present invention is provided with a first rib extending in the first direction on the inner wall of the second wall body. The first rib is located in the middle of the second wall body in the first direction. The explosion-proof hole is located in the middle of the first wall body in the first direction. And, the thickness of the first wall body is T1, and the distance between the side of the first rib facing the first wall body and the inner wall of the first wall body is W, where W / T1 ≤ 10, so that the distance between the first rib and the first wall body is relatively small. This structural design effectively improves the structural strength of the area of the second wall body close to the explosion-proof hole. Furthermore, when stamping the explosion-proof hole on the first wall body and welding the explosion-proof valve to the explosion-proof hole, the probability of deformation in the area of the second wall body close to the explosion-proof hole can be reduced. Furthermore, the dimensional accuracy of the explosion-proof hole can be improved, achieving the effect of improving the sealing performance between the explosion-proof valve and the first wall body, and improving the welding yield of the explosion-proof valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is an exploded structural schematic diagram of the battery case provided by the present invention;

[0024] Figure 2 is a structural schematic diagram of the battery case provided by the present invention;

[0025] Figure 3 is Figure 2 a cross-sectional view taken along the E-E direction of

[0026] Figure 4 is Figure 2 a first cross-sectional view taken along the F-F direction of

[0027] Figure 5 is Figure 2 a second cross-sectional view taken along the F-F direction of

[0028] Figure 6 is Figure 5 a partial enlarged view of A in

[0029] Figure 7 is Figure 2 a third cross-sectional view taken along the F-F direction of

[0030] Figure 8 is Figure 7 a partial enlarged view of B in

[0031] Figure 9 is a structural schematic diagram of the battery cell provided by the present invention.

[0032] In the figure:

[0033] D1, the first direction; D2, the second direction; D3, the third direction;

[0034] 10, battery case; 20, cover plate; 30, accommodation cavity; 31, opening; 40, stamping positioning block;

[0035] 100. First wall body; 110. Explosion-proof hole; 120. Convex rib structure; 121. Convex rib group; 1211. Convex rib; 1212. Limiting area; 200. Second wall body; 211. First convex rib; 220. Second convex rib; 230. Deformable area; 231. First deformation area; 232. Second deformation area; 300. Explosion-proof valve. Detailed implementation manners

[0036] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that, for the sake of convenience of description, only the parts related to the present invention are shown in the drawings, rather than all the structures.

[0037] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0038] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or may include that the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "above", and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "below", and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0039] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meanings.

[0040] This embodiment provides a battery case, which can improve the structural strength of the area of the second wall body close to the explosion-proof hole, and thus can reduce the probability of deformation of the area of the second wall body close to the explosion-proof hole when stamping the explosion-proof hole on the first wall body and when welding the explosion-proof valve to the explosion-proof hole.

[0041] Specifically, as Figures 1 to 6 shown, the battery case 10 includes a first wall body 100 and a second wall body 200. Among them, an explosion-proof hole 110 is provided on the first wall body 100. The explosion-proof hole 110 is located in the middle of the first wall body 100 in the first direction D1. An explosion-proof valve 300 is welded at the explosion-proof hole 110. The thickness of the first wall body 100 is T1. The second wall body 200 is adjacent to the first wall body 100. The edge of the second wall body 200 connected to the first wall body 100 extends along the first direction D1. A first rib 211 is provided on the inner wall of the second wall body 200. The first rib 211 extends along the first direction D1, and the first rib 211 is located in the middle of the second wall body 200 in the first direction D1. The distance between the side of the first rib 211 facing the first wall body 100 and the inner wall of the first wall body 100 is W, and W / T1≤10. Exemplarily, W / T1 can be 10, 8.5 or 7, etc.

[0042] Based on the above design, the battery case 10 is provided with a first rib 211 extending along the first direction D1 on the inner wall of the second wall body 200. The first rib 211 is located in the middle of the second wall body 200 in the first direction D1. The explosion-proof hole 110 is located in the middle of the first wall body 100 in the first direction D1. And the thickness of the first wall body 100 is T1. The distance between the side of the first rib 211 facing the first wall body 100 and the inner wall of the first wall body 100 is W, and W / T1≤10, so that the distance between the first rib 211 and the first wall body 100 is small. This structural design effectively improves the structural strength of the area of the second wall body 200 close to the explosion-proof hole 110 (hereinafter referred to as the easily deformed area 230). Thus, when stamping the explosion-proof hole 110 on the first wall body 100 and when welding the explosion-proof valve 300 to the explosion-proof hole 110, the probability of deformation of the area of the second wall body 200 close to the explosion-proof hole 110 can be reduced. Furthermore, the dimensional accuracy of the explosion-proof hole 110 can be improved, achieving the effect of improving the sealing performance between the explosion-proof valve 300 and the first wall body 100, and improving the welding yield of the explosion-proof valve 300.

[0043] Furthermore, W / T1>3.3. W / T1 can be 3.5, 5 or 6.6, etc. As Figure 3As shown, the above-mentioned deformable area 230 can be roughly divided into a first deformation area 231 and a second deformation area 232. Among them, the first deformation area 231 is closer to the first wall 100 than the second deformation area 232. Setting the ratio of W to T1 to be greater than 3.3 can avoid the problem that the distance between the first rib 211 and the first wall 100 is too small (i.e., the W value is too small). If the W value is too small, the first rib 211 can only significantly improve the structural strength of the first deformation area 231, and the effect of the first rib 211 on improving the structural strength of the second deformation area 232 is small. When punching the explosion-proof hole 110 on the first wall 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the second deformation area 232 is prone to deformation. Similarly, if the W value is too large (i.e., W / T1 is too large), the first rib 211 can only significantly improve the structural strength of the second deformation area 232, and the effect of the first rib 211 on improving the structural strength of the first deformation area 231 is small. When punching the explosion-proof hole 110 on the first wall 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the first deformation area 231 is prone to deformation. Therefore, when 3.3 < W / T1 ≤ 10, the first rib 211 can not only effectively improve the structural strength of the first deformation area 231, but also effectively improve the structural strength of the second deformation area 232, reducing the probability of the overall concave deformation of the deformable area 230 and providing guarantee for the welding yield of the explosion-proof valve 300.

[0044] Optionally, as Figure 6 shown, the thickness of the second wall 200 is T2, and the thickness of the first rib 211 protruding from the inner wall of the second wall 200 is H2, (T2 + H2) / T2 ≥ 1.3. Exemplarily, (T2 + H2) / T2 can be 1.3, 1.35 or 1.5, etc., ensuring that the first rib 211 protrudes from the inner wall of the second wall 200 by a certain thickness, so that the first rib 211 has sufficient structural strength to play a reliable supporting role for the deformable area 230, further reducing the probability of deformation problems in the deformable area 230.

[0045] Furthermore, (T2 + H2) / T2 < 1.6. Exemplarily, (T2 + H2) / T2 can be 1.55, 1.4 or 1.45, etc., ensuring that on the basis that the first rib 211 has sufficient supporting effect on the deformable area 230, the thickness of the first rib 211 protruding from the surface of the second wall 200 is reduced as much as possible, which can improve the utilization rate of the internal space of the battery case 10 and reduce the weight of the battery case 10, achieving the effect of improving the energy density of the battery cell, and can also reduce the production raw materials of the battery case 10 and lower the production cost.

[0046] Optionally, the thickness of the first wall 100 is greater than that of the second wall 200, that is, T1 is greater than T2, so that the first wall 100 has higher structural strength. When stamping the explosion-proof hole 110 on the first wall 100, the probability of deformation in the edge area of the explosion-proof hole 110 can be reduced, the dimensional accuracy of the explosion-proof hole 110 can be improved, and thus the welding yield of the explosion-proof valve 300 can be increased.

[0047] In this embodiment, T1≥1mm. Exemplarily, T1 can be 1mm, 1.5mm, 2mm, etc., to ensure that the first wall 100 has sufficient structural strength. T2≥0.5mm, and T2 can be 0.5mm, 1mm, 1.3mm, etc., to ensure that the second wall 200 has sufficient structural strength.

[0048] Optionally, as Figure 7 and Figure 8 shown, a rib structure 120 is provided on the first wall 100. The rib structure 120 is located at the edge of the explosion-proof hole 110, and at least part of the rib structure 120 is located on the side of the explosion-proof hole 110 facing the second wall 200. The setting of the rib structure 120 can improve the structural strength of the edge area of the explosion-proof hole 110, especially the structural strength of the area of the explosion-proof hole 110 facing the second wall 200. When stamping the explosion-proof hole 110, the deformation of the area of the explosion-proof hole 110 facing the second wall 200 can be reduced, and further the pulling force on the first wall 100 in the area of the explosion-proof hole 110 facing the second wall 200 can be reduced, and the probability of deformation of the easily deformed area 230 of the first wall 100 can be reduced.

[0049] Further, as Figure 4 、 Figure 7 and Figure 8 shown, the rib structure 120 surrounds the explosion-proof hole 110 and forms a limiting area 1212 on the outer periphery of the explosion-proof hole 110. The limiting area 1212 is used to define the position of the stamping positioning block 40. When stamping the explosion-proof hole 110 on the first wall 100, first clamp the stamping positioning block 40 in the limiting area 1212 to determine the stamping position, and then stamp out the explosion-proof hole 110 in the limiting area 1212. This structural design realizes the precise positioning of the stamping position of the explosion-proof hole 110 and has the effect of improving the position accuracy of the explosion-proof hole 110.

[0050] In this embodiment, the rib structure 120 includes two ribs 1211, and the two ribs 1211 are symmetrically arranged about the axis of the explosion-proof hole 110. A limiting area 1212 is formed between the two ribs 1211. When stamping the explosion-proof hole 110, just clamp the stamping positioning block 40 between the two ribs 1211.

[0051] In another embodiment, the rib structure 120 includes an annular rib 1211 disposed around the outer periphery of the explosion-proof hole 110. The inner region of the annular rib 1211 is the limiting region 1212. When stamping the explosion-proof hole 110, the stamping positioning block 40 can be clamped within the annular rib 1211.

[0052] In yet another embodiment, the rib structure 120 includes more than three ribs 1211, such as three ribs 1211, four ribs 1211, or more ribs 1211. The more than three ribs 1211 are spaced apart along the circumferential direction of the explosion-proof hole 110 (which can be evenly spaced or unevenly spaced). The region formed by enclosing the more than three ribs 1211 is the limiting region 1212. When stamping the explosion-proof hole 110, the stamping positioning block 40 can be clamped within the limiting region 1212.

[0053] Optionally, the number of the first wall bodies 100 and the second wall bodies 200 is two each. The two first wall bodies 100 are disposed opposite to each other along the third direction D3, and the two second wall bodies 200 are disposed opposite to each other along the second direction D2. The first direction D1, the second direction D2, and the third direction D3 are perpendicular to each other pairwise. Each end of each second wall body 200 in the third direction D3 is connected to a first wall body 100 respectively. That is, the battery case 10 in this embodiment has two explosion-proof holes 110, and an explosion-proof valve 300 is welded at each explosion-proof hole 110. Moreover, the two explosion-proof valves 300 are respectively located on the opposite sides of the battery case 10 in the third direction D3. When the gas pressure inside the battery case 10 reaches the bursting value of the explosion-proof valve 300, the high-pressure gas inside the battery case 10 can be discharged from the two explosion-proof valves 300 respectively, which not only shortens the gas flow path but also increases the gas discharge positions, having the effect of improving the exhaust efficiency. In this embodiment, the number of the second wall bodies 200 is two, and two first ribs 211 are provided on each second wall body 200. The two first ribs 211 on the same second wall body 200 are respectively grouped with a first wall body 100. In the third direction D3, the distance between the side of the first rib 211 of the same group facing the first wall body 100 and the inner wall of the first wall body 100 is W, ensuring the sealing performance between each explosion-proof valve 300 and the corresponding first wall body 100. Taking... Figure 3 shown as an example, in Figure 3A second wall body 200, two first wall bodies 100, and two first ribs 211 are shown. Among them, the two first wall bodies 100 are arranged oppositely in the third direction D3, and the two first ribs 211 are arranged oppositely in the third direction D3. The first wall body 100 located above and the first rib 211 located above form a group, and the first wall body 100 located below and the first rib 211 located below form a group. In the same group, the distance between the side of the first rib 211 facing the first wall body 100 and the inner wall of the first wall body 100 is W. After the electrode group (not shown in the figure) is installed in the accommodation cavity 30, the two first ribs 211 grouped with the same first wall body 100 can cooperate with each other in the second direction D2 to clamp the electrode group and prevent the electrode group from moving in the second direction D2. In addition, after the electrode group is installed in the accommodation cavity 30, the first rib 211 can separate the electrode group from the second wall body 200, forming a gap between the second wall body 200 and the electrode group, increasing the gas flow channel in the battery case 10. When the explosion-proof valve 300 explodes and exhausts gas, it is beneficial to achieve the effect of rapid exhaust.

[0054] It should be noted that Figure 3 Only examples of two deformable regions 230 on the same second wall body 200 are given. In practical applications, the two deformable regions 230 on the same second wall body 200 can be arranged at intervals, intersecting, or overlapping each other.

[0055] The battery case 10 provided in this embodiment is generally rectangular in structure. As Figure 1 shown, the two first wall bodies 100 are arranged oppositely in the third direction D3, and the two second wall bodies 200 are arranged oppositely in the second direction D2. The two first wall bodies 100 and the two second wall bodies 200 enclose an accommodation cavity 30 with an opening 31. The first direction D1, the second direction D2, and the third direction D3 are perpendicular to each other in pairs. Of course, in other implementation schemes, the battery case 10 can also be other shapes, such as a pentagonal prism shape or a hexagonal prism shape, etc.

[0056] As Figure 5As shown, in this embodiment, the ridge 1211 is located on the side of the first wall body 100 facing the accommodating cavity 30, that is, the ridge 1211 is protruded from the inner wall of the first wall body 100, and the two first wall bodies 100 have a total of four ridges 1211, and the four ridges 1211 are grouped in pairs to form two groups of ridge groups 121. In the same group of ridge groups 121, the two ridges 1211 are arranged opposite to each other in the third direction D3. After the pole group is inserted into the accommodating cavity 30, the two ridges 1211 in the same group of ridge groups 121 can cooperate with each other to clamp the pole group to prevent the pole group from moving in the third direction D3. In this embodiment, two groups of ridge groups 121 are provided, and the two groups of ridge groups 121 are distributed along the second direction D2, so that the pole group can be clamped at two positions in the second direction D2, thereby improving the limiting effect on the pole group, so that the battery cell has higher safety. In addition, the ridge 1211 is arranged on the side of the first wall 100 facing the accommodating cavity 30, so that a gap is formed between the first wall 100 and the electrode group, which increases the gas flow channel in the battery shell 10, and is conducive to achieving a quick exhaust effect when the explosion-proof valve 300 explodes to exhaust.

[0057] Alternatively, if Figure 1 , Figure 3 and Figure 4 As shown, the second wall 200 is further provided with a second rib 220 to further enhance the structural strength of the second wall 200 and further reduce the probability of deformation of the second wall 200, especially the probability of deformation in the middle area of ​​the second wall 200.

[0058] Furthermore, the second rib 220 is located on the side of the second wall 200 facing the accommodating cavity 30, and the thickness of the second rib 220 protruding from the second wall 200 is equal to the thickness of the first rib 211 protruding from the second wall 200. The friction force between the second rib 220 and the pole group can improve the limiting effect of the pole group and further prevent the pole group from moving in the accommodating cavity 30.

[0059] In this embodiment, the number of the second ribs 220 is two, which can reduce the weight and volume of the battery shell 10 as much as possible and improve the utilization rate of the internal space of the battery shell 10, thereby achieving the effect of improving the energy density of the battery cell.

[0060] Furthermore, the two second ribs 220 on the two second walls 200 are arranged opposite to each other in the second direction D2, so that the two second ribs 220 can cooperate with each other to clamp the pole group in the second direction D2, thereby improving the limiting effect on the pole group in the second direction D2.

[0061] In this embodiment, the first rib 211, the second rib 220, and the rib 1211 all extend along the first direction D1, and the dimensions of the first rib 211, the second rib 220, and the rib 1211 in the first direction D1 are equal, so as to reduce the production difficulty, improve the production efficiency, and reduce the production cost.

[0062]

[0063] Table 1 provides six groups of examples and five groups of comparative examples. The material of the battery case 10 in the six groups of examples and the five groups of comparative examples is imported aluminum alloy MXF2. The length (dimension in the first direction D1) of the explosion-proof valve 300 is 65 mm, and the width (dimension in the second direction D2) of the explosion-proof valve 300 is 15 mm. The welding power for welding the explosion-proof valve 300 to the explosion-proof hole 110 is 1050 W.

[0064] In Example 1, the thickness H1 of the rib 1211 protruding from the surface of the first wall 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall 200 is 0.15 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1 mm, the thickness T1 of the first wall 100 is 1 mm, the thickness T2 of the second wall 200 is 0.5 mm, the distance W between the side of the first rib 211 facing the first wall 100 and the side of the first wall 100 facing the first rib 211 is 3.5 mm, W / T1 is 3.5, (T2 + H2) / T2 is 1.3. After stamping the explosion-proof hole 110 on the first wall 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no out-of-tolerance concave occurs in the easily deformable area 230 of the second wall 200 (that is, the amount of depression of the easily deformable area 230 of the second wall 200 towards the accommodating cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0065] In Embodiment 2, the thickness H1 of the rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall body 200 is 0.18 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1.1 mm, the thickness T1 of the first wall body 100 is 1.2 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first rib 211 is 4 mm, W / T1 is 3.33, (T2 + H2) / T2 is 1.36. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no out-of-tolerance concave occurs in the deformable area 230 of the second wall body 200 (that is, the amount of depression of the deformable area 230 of the second wall body 200 towards the accommodation cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0066] In Embodiment 3, the thickness H1 of the rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall body 200 is 0.2 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1.1 mm, the thickness T1 of the first wall body 100 is 1.2 mm, the thickness T2 of the second wall body 200 is 0.55 mm, the distance W between the side of the first rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first rib 211 is 4.5 mm, W / T1 is 3.75, (T2 + H2) / T2 is 1.36. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no out-of-tolerance concave occurs in the deformable area 230 of the second wall body 200 (that is, the amount of depression of the deformable area 230 of the second wall body 200 towards the accommodation cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0067] In Embodiment 4, the thickness H1 of the rib 1211 protruding from the surface of the first wall 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall 200 is 0.23 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1.2 mm, the thickness T1 of the first wall 100 is 1 mm, the thickness T2 of the second wall 200 is 0.55 mm, the distance W between the side of the first rib 211 facing the first wall 100 and the side of the first wall 100 facing the first rib 211 is 4.8 mm, W / T1 is 4.8, (T2 + H2) / T2 is 1.42. After stamping the explosion-proof hole 110 on the first wall 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no excessive concave occurs in the deformable area 230 of the second wall 200 (that is, the amount of depression of the deformable area 230 of the second wall 200 towards the accommodating cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0068] In Embodiment 5, the thickness H1 of the rib 1211 protruding from the surface of the first wall 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall 200 is 0.25 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1.2 mm, the thickness T1 of the first wall 100 is 1.3 mm, the thickness T2 of the second wall 200 is 0.6 mm, the distance W between the side of the first rib 211 facing the first wall 100 and the side of the first wall 100 facing the first rib 211 is 5 mm, W / T1 is 3.85, (T2 + H2) / T2 is 1.42. After stamping the explosion-proof hole 110 on the first wall 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no excessive concave occurs in the deformable area 230 of the second wall 200 (that is, the amount of depression of the deformable area 230 of the second wall 200 towards the accommodating cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0069] In Embodiment 6, the thickness H1 of the rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall body 200 is 0.35 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1.2 mm, the thickness T1 of the first wall body 100 is 1.3 mm, the thickness T2 of the second wall body 200 is 0.6 mm, the distance W between the side of the first rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first rib 211 is 13 mm, W / T1 is 10, (T2 + H2) / T2 is 1.58. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, no out-of-tolerance concave occurs in the deformable area 230 of the second wall body 200 (that is, the amount of depression of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is less than 0.4 mm), the punching accuracy of the explosion-proof hole 110 is greater than 98%, and both the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 meet the technical requirements.

[0070] In Comparative Example 1, the thickness H1 of the rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first rib 211 protruding from the surface of the second wall body 200 is 0.2 mm, the width (dimension in the second direction D2) L of the rib 1211 is 1 mm, the thickness T1 of the first wall body 100 is 1 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first rib 211 is 1.5 mm, W / T1 is 1.5, (T2 + H2) / T2 is 1.4. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the amount of depression of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is greater than 0.4 mm (that is, out-of-tolerance concave occurs), the punching accuracy of the explosion-proof hole 110 is less than 98%, and the comprehensive yield rate of the helium leak detection test of the welded explosion-proof valve 300 (that is, the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 is lower than 96%.

[0071] In Comparative Example 2, the thickness H1 of the convex rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first convex rib 211 protruding from the surface of the second wall body 200 is 0.18 mm, the width (dimension in the second direction D2) L of the convex rib 1211 is 1 mm, the thickness T1 of the first wall body 100 is 1 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first convex rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first convex rib 211 is 1.8 mm, W / T1 is 1.8, (T2 + H2) / T2 is 1.36. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the depression amount of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is greater than 0.4 mm (i.e., an out-of-tolerance concave occurs), the punching accuracy of the explosion-proof hole 110 is less than 98%, and the comprehensive yield of the helium leak detection test of the welding of the explosion-proof valve 300 (i.e., the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 is lower than 96%.

[0072] In Comparative Example 3, the thickness H1 of the convex rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first convex rib 211 protruding from the surface of the second wall body 200 is 0.2 mm, the width (dimension in the second direction D2) L of the convex rib 1211 is 1 mm, the thickness T1 of the first wall body 100 is 1.2 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first convex rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first convex rib 211 is 3 mm, W / T1 is 2.5, (T2 + H2) / T2 is 1.4. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the depression amount of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is greater than 0.4 mm (i.e., an out-of-tolerance concave occurs), the punching accuracy of the explosion-proof hole 110 is less than 98%, and the comprehensive yield of the helium leak detection test of the welding of the explosion-proof valve 300 (i.e., the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 is lower than 96%.

[0073] In Comparative Example 4, the thickness H1 of the convex rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first convex rib 211 protruding from the surface of the second wall body 200 is 0.13 mm, the width (dimension in the second direction D2) L of the convex rib 1211 is 1 mm, the thickness T1 of the first wall body 100 is 1.2 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first convex rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first convex rib 211 is 4 mm, W / T1 is 3.33, (T2 + H2) / T2 is 1.26. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the depression amount of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is greater than 0.4 mm (i.e., there is an out-of-tolerance concave), the punching accuracy of the explosion-proof hole 110 is less than 98%, and the comprehensive yield rate of the helium leak detection test of the welded explosion-proof valve 300 (i.e., the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 is lower than 96%.

[0074] In Comparative Example 5, the thickness H1 of the convex rib 1211 protruding from the surface of the first wall body 100 is 0.35 mm, the thickness H2 of the first convex rib 211 protruding from the surface of the second wall body 200 is 0.2 mm, the width (dimension in the second direction D2) L of the convex rib 1211 is 1 mm, the thickness T1 of the first wall body 100 is 1.2 mm, the thickness T2 of the second wall body 200 is 0.5 mm, the distance W between the side of the first convex rib 211 facing the first wall body 100 and the side of the first wall body 100 facing the first convex rib 211 is 13.5 mm, W / T1 is 11.25, (T2 + H2) / T2 is 1.4. After stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the depression amount of the deformable area 230 of the second wall body 200 towards the accommodating cavity 30 is greater than 0.4 mm (i.e., there is an out-of-tolerance concave), the punching accuracy of the explosion-proof hole 110 is less than 98%, and the comprehensive yield rate of the helium leak detection test of the welded explosion-proof valve 300 (i.e., the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 is lower than 96%.

[0075] In summary, when 3.3 < W / T1 ≤ 10, 1.3 ≤ (T2 + H2) / T2 < 1.6, T2 ≥ 0.5 mm, and T1 ≥ 1 mm, after stamping the explosion-proof hole 110 on the first wall body 100 and welding the explosion-proof valve 300 at the explosion-proof hole 110, the deformable area 230 of the second wall body 200 does not have an out-of-tolerance concave, the punching accuracy of the explosion-proof hole 110 is greater than 98%, and the helium leak detection test of the welded explosion-proof valve 300 (i.e., the sealing test between the explosion-proof valve 300 and the second wall body 200) and the appearance inspection of the battery case 10 can meet the technical requirements.

[0076] It should be noted that the punching accuracy of the above explosion-proof hole 110 refers to the sum of the dimensional accuracy and the position accuracy of the explosion-proof hole 110.

[0077] The battery case 10 provided in this embodiment can be made by using relatively mature stamping, stretching and extrusion processes in the art. Moreover, when stamping the explosion-proof hole 110, the probability of deformation of the easily deformable area 230 of the second wall body 200 is relatively low. When welding the explosion-proof valve 300 to the explosion-proof hole 110, the probability of deformation of the easily deformable area 230 of the second wall body 200 is relatively low, which provides a strong guarantee for the welding yield of the explosion-proof valve 300 and is conducive to realizing the automated batch production of the battery case 10.

[0078] This embodiment also provides a battery cell, as Figure 9 shown. The battery cell includes a pole group (not shown in the figure), a cover plate 20, and the above-mentioned battery case 10. The housing mechanism is provided with a receiving cavity 30 with an opening 31. The pole group is arranged in the receiving cavity 30, and the cover plate 20 seals the opening 31. By using the above-mentioned battery case 10 for this battery cell, when stamping the explosion-proof hole 110 on the first wall body 100 and when welding the explosion-proof valve 300 to the explosion-proof hole 110, the probability of deformation problems in the area of the second wall body 200 close to the explosion-proof hole 110 (i.e., the easily deformable area 230) can be reduced. Furthermore, the dimensional accuracy of the explosion-proof hole 110 can be improved, achieving the effect of improving the sealing performance between the explosion-proof valve 300 and the first wall body 100, and improving the welding yield of the explosion-proof valve 300.

[0079] Compared with setting the explosion-proof valve 300 on the cover plate 20 at the end of the battery case 10, in this embodiment, the explosion-proof valve 300 is arranged on the battery case 10. When the explosion-proof valve 300 bursts open for exhaust, the path of the gas in the battery case 10 flowing to the explosion-proof valve 300 is shorter, which is conducive to quickly discharging the high-pressure gas in the battery case 10 and has the effect of improving the use safety of the battery cell.

[0080] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A battery case, characterized in that: include: A first wall body (100), wherein an explosion-proof hole (110) is provided on the first wall body (100), the explosion-proof hole (110) is located in the middle of the first wall body (100) in a first direction (D1), and the thickness of the first wall body (100) is T1; A second wall body (200), the second wall body (200) is arranged adjacent to the first wall body (100), the edge connecting the second wall body (200) and the first wall body (100) extends along the first direction (D1), a first convex rib (211) is provided on the inner wall of the second wall body (200), the first convex rib (211) extends along the first direction (D1), and the first convex rib (211) is located in the middle of the second wall body (200) in the first direction (D1), and the distance between the first convex rib (211) facing the first wall body (100) and the inner wall of the first wall body (100) is W, and W / T1≤10.

2. The battery case according to claim 1, characterized in that: W / T1>3.

3.

3. The battery case according to claim 1, characterized in that: The thickness of the first wall (100) is greater than the thickness of the second wall (200).

4. The battery case according to any one of claims 1 to 3, characterized in that: The thickness of the second wall (200) is T2, the thickness of the first convex rib (211) protruding from the inner wall of the second wall (200) is H2, and (T2+H2) / T2≥1.

3.

5. The battery case according to claim 4, characterized in that: (T2+H2) / T2<1.

6.

6. The battery case according to any one of claims 1 to 3, characterized in that: A ridge structure (120) is provided on the first wall (100), the ridge structure (120) is located at the edge of the explosion-proof hole (110), and at least part of the ridge structure (120) is located on a side of the explosion-proof hole (110) facing the second wall (200).

7. The battery case according to claim 6, characterized in that: The convex ridge structure (120) is arranged around the explosion-proof hole (110) and forms a limiting area (1212) on the periphery of the explosion-proof hole (110), wherein the limiting area (1212) is used to limit the position of the punching positioning block (40).

8. The battery case according to any one of claims 1 to 3, characterized in that: The number of the first wall body (100) and the number of the second wall body (200) are both two, the two first wall bodies (100) are arranged opposite to each other along a third direction (D3), and the two second wall bodies (200) are arranged opposite to each other along a second direction (D2), the first direction (D1), the second direction (D2) and the third direction (D3) are perpendicular to each other, and each of the second wall bodies (200) is connected to one of the first wall bodies (100) at two ends in the third direction (D3), and each of the second wall bodies (200) is provided with two first convex ribs (211), and the two first convex ribs (211) on the same second wall body (200) are arranged in a group with one of the first wall bodies (100), and in the third direction (D3), the distance between the side of the first convex ribs (211) in the same group facing the first wall body (100) and the inner wall of the first wall body (100) is W.

9. The battery case according to claim 8, characterized in that: The second wall (200) is also provided with a second convex rib (220).

10. A battery cell, characterized in that: The battery shell (10) comprises a pole group and any one of claims 1 to 9, wherein the shell structure is provided with a receiving cavity (30), and the pole group is arranged in the receiving cavity (30).

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