Battery cell shell and battery cell

Abstract

The invention relates to the technical field of energy storage equipment, in particular to a battery cell shell and a battery cell, and the battery cell shell comprises an anti-explosion valve, a sealing ring, a shell body and a press fitting piece. The anti-explosion valve is provided with a weak part, and the sealing ring is arranged on the edge of the anti-explosion valve in a sleeving mode in the circumferential direction The shell body is provided with a first side wall provided with a first anti-explosion through hole, the press-fitting piece is provided with a second anti-explosion through hole, the press-fitting piece is riveted to the first side wall, the anti-explosion valve is clamped between the press-fitting piece and the first side wall, and at least part of the sealing ring is clamped between the press-fitting piece and the first side wall in the circumferential direction so that the press-fitting piece can be in sealed butt joint with the first side wall. The projection of the weak part towards the first side wall is located in the first anti-explosion through hole, and the projection of the weak part towards the press fitting piece is located in the second anti-explosion through hole. The battery cell comprises a battery cell top cover, a pole group and the battery cell shell, the battery cell top cover hermetically covers the opening of the battery cell shell to form a shell of the battery cell, and the pole group is arranged in the shell. The battery cell can prevent the anti-explosion valve and the shell body from deforming, and the process yield is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage devices, and particularly to a cell housing and a cell. Background Art

[0002] Setting an explosion-proof valve on a cell can effectively improve the safety of the cell. An explosion-proof valve made of pure aluminum can effectively ensure the accuracy of the bursting pressure. However, due to the relatively soft pure aluminum material, when the explosion-proof valve is welded to the cell housing, the explosion-proof valve is prone to deformation, and the stability of its bursting pressure depends on the quality of the welding process. Therefore, the use of an explosion-proof valve made of pure aluminum has high requirements for the welding process and low process yield, which is not conducive to mass production.

[0003] Meanwhile, in the prior art, the position of the explosion-proof valve is generally set on the cell top cover. However, since the cell top cover is located at one end of the cell in the length direction, the path for gas to reach the explosion-proof valve is relatively long, which is not conducive to improving the safety of the cell. Setting the explosion-proof valve on the side wall of the cell housing can shorten the exhaust path and improve the safety performance. However, compared with the top cover, the wall thickness of the side wall of the cell housing is smaller, and in order to arrange the explosion-proof valve, an opening needs to be made on the side wall of the cell housing, and the structural strength at the opening is further reduced. Therefore, the structure of the cell housing at the welding position of the explosion-proof valve is weak, and welding is likely to cause deformation of the housing, resulting in rubbing of the electrode assembly during shell insertion, affecting the subsequent assembly and use of the cell. Summary of the Invention

[0004] An object of the present invention is to provide a cell housing that can prevent deformation of the explosion-proof valve and the housing body and improve the process yield.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] Provide a cell housing, including:

[0007] An explosion-proof valve having a weak part;

[0008] A sealing ring sleeved around the edge of the explosion-proof valve in the circumferential direction;

[0009] A housing body having a first side wall, and a first explosion-proof through hole is opened on the first side wall;

[0010] A pressing member having a second explosion-proof through hole, the pressing member is riveted to the first side wall, the explosion-proof valve is clamped between the pressing member and the first side wall, and at least part of the sealing ring is clamped between the pressing member and the first side wall in the circumferential direction to make the pressing member and the first side wall in sealed butt joint, and the projection of the weak part towards the first side wall is located in the first explosion-proof through hole, and the projection of the weak part towards the pressing member is located in the second explosion-proof through hole.

[0011] Optionally, the end face of the sealing ring facing the first side wall has a first protruding ring and a second protruding ring arranged coaxially. The second protruding ring is disposed around the first protruding ring. The first protruding ring covers the end face of the explosion-proof valve facing the first side wall. The first protruding ring is partially clamped between the first side wall and the press-fitting member. The second protruding ring is clamped between the press-fitting member and the first side wall.

[0012] Optionally, along the axial direction of the sealing ring, the second protruding ring protrudes more than the first protruding ring.

[0013] Optionally, along the axial direction of the sealing ring, the height h of the part where the second protruding ring protrudes more than the first protruding ring is less than or equal to 0.3 mm.

[0014] Optionally, the sealing ring has a connected inner ring and outer ring. The inner ring wraps the edge of the explosion-proof valve. The outer ring is clamped between the first side wall and the press-fitting member. The compression thickness T2 of the outer ring satisfies 0.35 mm ≤ T2 ≤ 0.6 mm.

[0015] Optionally, the sealing ring has an inner ring. The cross-section of the inner ring is a C-shaped structure. The opening of the C-shaped structure faces the explosion-proof valve, and the C-shaped structure wraps the edge of the explosion-proof valve.

[0016] Optionally, a first sinking groove and a second sinking groove are formed on the end face of the press-fitting member facing the first side wall. The second sinking groove is formed at the bottom of the first sinking groove. The second explosion-proof through hole is formed at the bottom of the second sinking groove. The sealing ring has a connected inner ring and outer ring. The inner ring wraps the edge of the explosion-proof valve. The inner ring is located in the second sinking groove. The outer ring is clamped between the first side wall and the bottom of the first sinking groove.

[0017] Optionally, the first side wall has a riveting post. The riveting post passes through the riveting hole of the press-fitting member and is riveted to the press-fitting member. The riveting post is welded to the press-fitting member.

[0018] Optionally, the thickness T1 of the explosion-proof valve at the position where the weak part is not provided satisfies T1 ≥ 0.5 mm.

[0019] Another object of the present invention is to provide an electric core capable of preventing deformation of the explosion-proof valve and the shell body and improving the process yield.

[0020] To achieve this object, the present invention adopts the following technical solutions:

[0021] Provide an electric core, including an electric core top cover, a pole group, and the above-mentioned electric core shell. The electric core top cover is hermetically covered at the opening of the electric core shell to form the outer shell of the electric core. The pole group is arranged inside the outer shell.

[0022] Advantages of the present invention:

[0023] The present invention provides an electric core housing, which includes an explosion-proof valve, a sealing ring, a housing body and a pressing member. Among them, the explosion-proof valve has a weak part, and the sealing ring is sleeved around the edge of the explosion-proof valve along the circumferential direction. The housing body has a first side wall, and a first explosion-proof through hole is formed in the first side wall. A second explosion-proof through hole is formed in the pressing member, and the pressing member is riveted to the first side wall. The explosion-proof valve is clamped between the pressing member and the first side wall, and at least part of the sealing ring is clamped between the pressing member and the first side wall along the circumferential direction, so that the pressing member and the first side wall are hermetically butted. The projection of the weak part towards the first side wall is located in the first explosion-proof through hole, and the projection of the weak part towards the pressing member is located in the second explosion-proof through hole. This electric core housing presses the explosion-proof valve on the electric core housing through the pressing member, ensures the firm installation of the explosion-proof valve by riveting the pressing member on the electric core housing, and then ensures the hermetic butt joint between the pressing member and the electric core housing through the sealing ring, thus completely replacing the process of welding the explosion-proof valve. Since there is no need to weld the explosion-proof valve anymore, the problems of deformation of the explosion-proof valve and the housing body are fundamentally solved, thereby improving the manufacturing yield of the electric core.

[0024] The present invention also provides an electric core, which includes an electric core top cover, a pole group and the above-mentioned electric core housing. The electric core top cover is hermetically covered at the opening of the electric core housing to form the outer shell of the electric core, and the pole group is arranged inside the outer shell. This electric core can prevent the deformation of the explosion-proof valve and the housing body and improve the manufacturing yield. Description of the drawings

[0025] Figure 1 is a schematic structural diagram of the electric core housing provided by the embodiment of the present invention from the first perspective;

[0026] Figure 2 is an exploded view of the electric core housing provided by the embodiment of the present invention;

[0027] Figure 3 is a schematic structural diagram of the electric core housing provided by the embodiment of the present invention from the second perspective;

[0028] Figure 4 is Figure 3 the A-A cross-sectional view in

[0029] Figure 5 is Figure 4 the enlarged view at B in

[0030] Figure 6 is a schematic structural diagram of the pressing member provided by the embodiment of the present invention;

[0031] Figure 7 is a schematic structural diagram of the sealing ring provided by the embodiment of the present invention;

[0032] Figure 8It is an assembly schematic diagram of an explosion-proof valve, a sealing ring and a press-fitting part provided by an embodiment of the present invention;

[0033] Figure 9 is Figure 8 the C-C cross-sectional view in

[0034] Figure 10 is Figure 9 the enlarged view at position D in

[0035] In the figure:

[0036] 1. Explosion-proof valve;

[0037] 2. Sealing ring; 21. Inner ring; 211. First protruding ring; 22. Outer ring; 221. Second protruding ring; 23. Connecting ring;

[0038] 3. Shell body; 31. First side wall; 311. First explosion-proof through hole; 312. Riveting post; 313. Limiting groove;

[0039] 4. Press-fitting part; 41. Second explosion-proof through hole; 42. First sink; 43. Second sink; 44. Riveting hole; 45. Riveting sink. Detailed implementation manners

[0040] Before explaining any embodiment of the present application in detail, it should be understood that the present application is not limited to the structural details and component arrangements described in the following description or shown in the above drawings.

[0041] In the present application, the terms "include", "comprise", "have" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0042] In the present application, the term "and / or" is a relationship description of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the present application, the character " / " generally represents an "and / or" relationship between the associated objects before and after.

[0043] In this application, the terms "connected", "combined", "coupled", and "mounted" can be direct connections, combinations, couplings, or mountings, or can be indirect connections, combinations, couplings, or mountings. Among them, by way of example, a direct connection means that two parts or components are connected together without the need for an intermediate member, and an indirect connection means that two parts or components are respectively connected to at least one intermediate member, and these two parts or components are connected through the intermediate member. In addition, "connected" and "coupled" are not limited to physical or mechanical connections or couplings, and can include electrical connections or couplings.

[0044] In this application, those of ordinary skill in the art will understand that relative terms used in connection with a quantity or condition (such as "about", "approximately", "substantially", etc.) are intended to include the recited value and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances resulting from manufacturing, assembly, use in relation to a particular value, etc. Such terms should also be considered to disclose a range defined by the absolute values of two endpoints. A relative term may refer to a plus or minus a certain percentage (such as 1%, 5%, 10% or more) of the indicated value. Numerical values without the use of relative terms should also be disclosed as having tolerances. In addition, when expressing a relative angular positional relationship (such as substantially parallel, substantially perpendicular), "substantially" may refer to a plus or minus a certain number of degrees (such as 1 degree, 5 degrees, 10 degrees or more) based on the indicated angle.

[0045] In this application, those of ordinary skill in the art will understand that the functions performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0046] In this application, the directional terms such as "upper", "lower", "left", "right", "front", "rear", etc. are described based on the orientation and positional relationship shown in the drawings, and should not be construed as a limitation on the embodiments of this application. In addition, in the context, it should also be understood that when it is mentioned that one element is connected "above" or "below" another element, it can not only be directly connected "above" or "below" another element, but also be indirectly connected "above" or "below" another element through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, rear side, etc. not only represent the positive direction, but can also be understood as the side direction. For example, below can include directly below, lower left, lower right, front lower, and rear lower, etc.

[0047] Setting an explosion-proof valve on the battery cell can effectively improve the safety of the battery cell, and the explosion-proof valve made of pure aluminum can effectively ensure the accuracy of the bursting pressure. However, due to the relatively soft pure aluminum material, when the explosion-proof valve is welded to the outer shell of the battery cell, the explosion-proof valve is prone to deformation, and the stability of its bursting pressure depends on the quality of the welding process. Therefore, the explosion-proof valve made of pure aluminum has high requirements for the welding process and low process yield, which is not conducive to mass production.

[0048] At the same time, in the prior art, the position of the explosion-proof valve is generally set on the top cover of the battery cell. However, since the top cover of the battery cell is located at one end of the length direction of the battery cell, the path for the gas to reach the explosion-proof valve is relatively long, which is not conducive to improving the safety of the battery cell. Setting the explosion-proof valve on the side wall of the battery cell housing can shorten the exhaust path and improve the safety performance. However, compared with the top cover, the wall thickness of the side wall of the battery cell housing is smaller, and in order to arrange the explosion-proof valve, an opening needs to be made on the side wall of the battery cell housing, and the structural strength at the opening is further reduced. Therefore, the structure of the battery cell housing at the welding position of the explosion-proof valve is weak, and welding is likely to cause deformation of the housing, resulting in rubbing of the electrode group during shell insertion, affecting the subsequent assembly and use of the battery cell.

[0049] Therefore, this embodiment provides a battery cell housing to solve the above problems. The battery cell housing can prevent the explosion-proof valve 1 and the housing body 3 from deforming and improve the process yield.

[0050] As Figures 1 - 10 shown, the battery cell housing of this embodiment includes an explosion-proof valve 1, a sealing ring 2, a housing body 3, and a pressing member 4. Among them, the explosion-proof valve 1 has a weak part, and the sealing ring 2 is sleeved around the edge of the explosion-proof valve 1 in the circumferential direction. Optionally, the housing body 3 is formed by processes such as extrusion and high-frequency welding and has good structural strength. The housing body 3 has a first side wall 31, and a first explosion-proof through hole 311 is opened on the first side wall 31. A second explosion-proof through hole 41 is opened on the pressing member 4, and the pressing member 4 is riveted to the first side wall 31. The explosion-proof valve 1 is clamped between the pressing member 4 and the first side wall 31, and the sealing ring 2 is at least partially clamped between the pressing member 4 and the first side wall 31 in the circumferential direction, so that the pressing member 4 and the first side wall 31 are in sealed butt joint. The projection of the weak part facing the first side wall 31 is located in the first explosion-proof through hole 311, and the projection of the weak part facing the pressing member 4 is located in the second explosion-proof through hole 41. Optionally, in this embodiment, the first side wall 31 is located at one end of the housing body 3 along its own width direction.

[0051] This battery cell housing presses the explosion-proof valve 1 on the battery cell housing through the pressing member 4, ensures the firm installation of the explosion-proof valve 1 by riveting the pressing member 4 to the battery cell housing, and then ensures the sealed butt joint between the pressing member 4 and the battery cell housing through the sealing ring 2, which can completely replace the process of welding the explosion-proof valve 1. Since there is no longer a need to weld the explosion-proof valve 1, the problem of deformation of the explosion-proof valve 1 and the housing body 3 is fundamentally solved, thereby improving the process yield of the battery cell.

[0052] AsFigure 5 and Figure 7 As shown in Figure 7 , optionally, the end face of the sealing ring 2 facing the first side wall 31 has a first protruding ring 211 and a second protruding ring 221 arranged coaxially. The second protruding ring 221 is disposed around the first protruding ring 211. The first protruding ring 211 covers the end face of the explosion-proof valve 1 facing the first side wall 31. The first protruding ring 211 is partially clamped between the first side wall 31 and the press-fitting member 4, and the second protruding ring 221 is clamped between the press-fitting member 4 and the first side wall 31.

[0053] Optionally, the sealing ring 2 has a connected inner ring 21 and outer ring 22. The inner ring 21 wraps the edge of the explosion-proof valve 1, and the outer ring 22 is clamped between the first side wall 31 and the press-fitting member 4. That is, the inner ring 21 has the first protruding ring 211, and the outer ring 22 has the second protruding ring 221. The compression thickness T2 of the outer ring 22 satisfies 0.35 mm ≤ T2 ≤ 0.6 mm. When the compression thickness T2 of the outer ring 22 is less than 0.35 mm, the sealing effect here is poor, which will cause leakage at the explosion-proof valve 1 and affect the yield of the battery cell. However, when the compression thickness T2 of the outer ring 22 is greater than 0.6 mm, the reaction force received by the press-fitting member 4 is too large, which is not conducive to the riveting and fixing of the press-fitting member 4, and the cost of the sealing ring 2 will increase.

[0054] Optionally, the sealing ring 2 has an inner ring 21. The cross-section of the inner ring 21 is a C-shaped structure. The opening of the C-shaped structure faces the explosion-proof valve 1, and the C-shaped structure wraps the edge of the explosion-proof valve 1. The C-shaped structure has a first protruding ring 211, a covering ring, and a third protruding ring connected in sequence. Among them, the covering ring is located outside the explosion-proof valve 1 along its radial direction, and the third protruding ring is located on the side of the explosion-proof valve 1 facing the press-fitting member 4. The inner ring 21 of the C-shaped structure can ensure firm fixation with the explosion-proof valve 1, and the explosion-proof valve 1 is not easily displaced and separated from the inner ring 21.

[0055] Optionally, the sealing ring 2 has a connecting ring 23. The connecting ring 23 is used to connect the inner ring 21 and the outer ring 22. That is, the inner circumferential wall of the connecting ring 23 is connected to the outer wall of the inner ring 21, and the outer circumferential wall of the connecting ring 23 is connected to the inner wall of the outer ring 22. The thickness of the connecting ring 23 is less than the thickness of the outer ring 22, and the connecting ring 23 does not contact the first side wall 31. Therefore, the connecting ring 23 does not have a sealing effect and is only used to connect the inner ring 21 and the outer ring 22.

[0056] Optionally, a first sinking groove 42 and a second sinking groove 43 are provided on the end face of the press-fit member 4 facing the first side wall 31. The second sinking groove 43 is provided at the bottom of the first sinking groove 42, and the second explosion-proof through hole 41 is provided at the bottom of the second sinking groove 43. The inner ring 21 of the sealing ring 2 is located in the second sinking groove 43, the outer ring 22 is clamped between the first side wall 31 and the bottom of the first sinking groove 42, and the connecting ring 23 is also located at the first sinking groove 42. That is, at both ends of the outer ring 22 along the axial direction of the sealing ring 2, one end is the second protruding ring 221, which abuts against the first side wall 31, and the other end abuts against the bottom of the first sinking groove 42. At both ends of the inner ring 21 along the axial direction of the sealing ring 2, one end is the first protruding ring 211, which abuts against the first side wall 31, and the other end abuts against the bottom of the second sinking groove 43. By providing the first sinking groove 42 and the second sinking groove 43 with a height difference on the press-fit member 4, the maximum thickness of the outer ring 22 can be made smaller than the maximum thickness of the inner ring 21. On the one hand, the inner ring 21 needs to wrap the explosion-proof valve 1 and requires a certain thickness. On the other hand, the outer ring 22 does not need to have the same thickness as the inner ring 21, thus saving the material cost of the sealing ring 2.

[0057] Optionally, as Figure 10 shown, along the axial direction of the sealing ring 2, the second protruding ring 221 protrudes more than the first protruding ring 211. Figure 10 H1, H2, and h are marked in

[0058] where H1 is the overall thickness of the outer ring 22, and T2 is the difference between H1 and the depression depth of the first sinking groove 42. H2 is the vertical distance between the plane where the first protruding ring 211 is located and the bottom of the first sinking groove 42, and h is the difference between H1 and H2. The second protruding ring 221 protruding more than the first protruding ring 211 means that H1 is greater than H2 and h is greater than 0. That is, the second protruding ring 221 mainly bears the pressure from the first side wall 31 and the press-fit member 4, which can not only ensure the sealed docking between the first side wall 31 and the press-fit member 4, but also avoid the situation that the first protruding ring 211 is over-pressurized and the edge of the explosion-proof valve 1 is deformed and blasted unstably due to excessive force.

[0059] Optionally, the thickness T1 at the position where the explosion-proof valve 1 is not provided with a weak part satisfies T1 ≥ 0.5 mm to ensure the structural strength of the explosion-proof valve 1 and prevent its edge from being deformed by pressure.

[0060] Optionally, there is a riveting post 312 on the first side wall 31. The riveting post 312 passes through the riveting hole 44 of the press-fitting part 4 and is riveted to the press-fitting part 4, and the riveting post 312 is welded to the press-fitting part 4. That is, by adding a welding step on the basis of riveting, the connection strength between the press-fitting part 4 and the first side wall 31 can be further improved. And since the welding area is limited to the riveting post 312, compared with directly welding the explosion-proof valve 1 on the first side wall 31, welding on the riveting post 312 can greatly reduce the welding area and reduce the welding heat, thereby avoiding affecting the first side wall 31.

[0061] Optionally, a riveting sink 45 is provided around the riveting hole 44 of the press-fitting part 4. The riveting sink 45 faces the outside of the battery cell, and the deformed part of the riveting post 312 is located in the riveting sink 45.

[0062] Optionally, in order to facilitate assembly and positioning, a limiting groove 313 is provided on the first side wall 31. Part of the press-fitting part 4 is located in the limiting groove 313, and the riveting post 312 is located at the bottom of the limiting groove 313.

[0063] In addition, it should be noted that although the drawings only show that along the length direction of the explosion-proof valve 1, both outer ends 22 of the sealing ring 2 are clamped between the first side wall 31 and the bottom of the first sink 42. In fact, along the circumferential direction of the sealing ring 2, all parts of the outer ring 22 are clamped between the first side wall 31 and the bottom of the first sink 42, and all parts of the inner ring 21 also have part of them clamped between the first side wall 31 and the bottom of the second sink 43. Therefore, along the circumferential direction of the first explosion-proof through hole 311, there is two-stage sealing everywhere between the first side wall 31 and the press-fitting part 4.

[0064] In order to verify the effect of the battery cell housing in solving the deformation problems of the housing body 3 and the explosion-proof valve 1, this embodiment provides a set of test data as shown in Table 1 and Table 2 below. Table 1 lists the dimensions of the battery cell housings of six groups of examples, and Table 2 lists the dimensions of the battery cell housings of five groups of comparative examples. The similarities of the battery cell housings of the six groups of examples and the five groups of comparative examples include: the material of the explosion-proof valve 1 is MXF2, the material of the press-fitting part 4 is three-series aluminum, the material of the sealing ring 2 is fluororubber, which has good high-temperature resistance, the thickness H1 of the outer ring 22 is 0.9 mm, and the thickness H3 of the first protruding ring 211 of the inner ring 21 covering the explosion-proof valve 1 is 0.35 mm.

[0065] Table 1

[0066]

[0067]

[0068] Table 2

[0069]

[0070] For each key dimension parameter of the battery cell housing of the six groups of examples in Table 1 above, they all meet the above more optimal value ranges. For example, the height h of the part where the second protruding ring 221 protrudes more than the first protruding ring 211, that is, the value of H1 - H2 in the table is greater than 0 and less than or equal to 0.3 mm. The compression thickness T2 of the outer ring 22 all satisfies 0.35 mm ≤ T2 ≤ 0.6 mm, and the thickness T1 of the explosion-proof valve 1 is all 0.5 mm. After testing, the explosion-proof valve 1 and the housing body 3 of the battery cell housings of these six groups have not deformed. It is not easy for the electrode group to be scratched when inserted into the housing. The anti-pushing ability and anti-twisting ability of the pressing part 4 both meet the quality requirements. The airtightness detection at the explosion-proof valve 1 is qualified, and the bursting value of the explosion-proof valve 1 also meets the requirements. It can be seen that using the pressing part 4 to fix the explosion-proof valve 1 can completely solve the deformation problem of the explosion-proof valve 1 and the housing body 3 caused by welding, and by meeting the above more optimal value ranges, the connection strength of the explosion-proof valve 1 and the airtightness at the explosion-proof valve 1 can be ensured to meet the technical requirements.

[0071] In the battery cell housing of Comparative Example 1 in Table 2 above, the first protruding ring 211 protrudes more than the second protruding ring 221, and the protruding height is 0.07 mm. After testing, the explosion-proof valve 1 of this group of battery cell housings is deformed at the position where it contacts the sealing ring 2, that is, the inner ring 21 is under excessive pressure from the first side wall 31 and the pressing part 4, resulting in the deformation of the explosion-proof valve 1 due to force. Although the anti-pushing ability and anti-twisting ability of the pressing part 4 of this group of battery cell housings both meet the quality requirements, that is, the explosion-proof valve 1 is firmly connected at the first side wall 31, the yield rates of the helium detection and bursting value detection of the explosion-proof valve 1 are both lower than 99%, and the appearance of the explosion-proof valve 1 does not meet the quality requirements. It can be seen that even if the thickness H1 of the outer ring 22 remains unchanged, and the first protruding ring 211 only protrudes a very small height more than the second protruding ring 221, it is sufficient to affect the shape of the explosion-proof valve 1.

[0072] In the battery cell housing of Comparative Example 2 in Table 2 above, the height by which the first protruding ring 211 protrudes more than the second protruding ring 221 is further increased, and the protruding height is 0.1 mm. After testing, the explosion-proof valve 1 of this group of battery cell housings is deformed at the position where it contacts the sealing ring 2, that is, the inner ring 21 is under excessive pressure from the first side wall 31 and the pressing part 4, resulting in the deformation of the explosion-proof valve 1 due to force. Although the anti-pushing ability and anti-twisting ability of the pressing part 4 of this group of battery cell housings still meet the quality requirements, that is, the explosion-proof valve 1 is firmly connected at the first side wall 31, the yield rates of the helium detection and bursting value detection of the explosion-proof valve 1 are also both lower than 99%, and the appearance of the explosion-proof valve 1 does not meet the quality requirements.

[0073] In Comparative Example 3 in Table 2 above, the height by which the first protruding ring 211 of the battery cell housing protrudes more than the second protruding ring 221 is further increased, and the protruding height is 0.15 mm. After testing, it is found that the explosion-proof valve 1 of this group of battery cell housings is deformed at the position where it contacts the sealing ring 2, that is, the pressure on the inner ring 21 from the first side wall 31 and the pressing member 4 is further increased, resulting in more serious deformation of the explosion-proof valve 1 under force. Although the anti-pushing ability and anti-torsion ability of the pressing member 4 of this group of battery cell housings still meet the quality requirements, that is, the explosion-proof valve 1 is firmly connected at the first side wall 31, the yield rates of helium leak detection and bursting value detection of the explosion-proof valve 1 are both lower than 99%, and the appearance of the explosion-proof valve 1 does not meet the quality requirements.

[0074] In Comparative Example 4 in Table 2 above, the compression thickness T2 of the outer ring 22 of the sealing ring 2 of the battery cell housing is less than 0.35 mm, and the compression thickness T2 of the outer ring 22 of this group of battery cell housings is 0.3 mm. After testing, it is found that the explosion-proof valve 1 of this group of battery cell housings is deformed at the position where it contacts the sealing ring 2, that is, the compression thickness of the outer ring 22 is insufficient and cannot withstand the pressure from the first side wall 31 and the pressing member 4, so that the inner ring 21 is under excessive force and the explosion-proof valve 1 is deformed under force. Although the anti-pushing ability and anti-torsion ability of the pressing member 4 of this group of battery cell housings still meet the quality requirements, that is, the explosion-proof valve 1 is firmly connected at the first side wall 31, the helium leak detection yield rate of the explosion-proof valve 1 is lower than 97%, and the appearance of the explosion-proof valve 1 does not meet the quality requirements. It can be seen that even if the second protruding ring 221 protrudes more than the first protruding ring 211, when the compression thickness of the second protruding ring 221 is insufficient, the inner ring 21 is still under excessive pressure, so that the explosion-proof valve 1 is deformed under force, affecting the sealed contact between the explosion-proof valve 1 and the sealing ring 2 and causing a leakage risk here.

[0075] In Comparative Example 5 in Table 2 above, the compression thickness T2 of the outer ring 22 of the sealing ring 2 of the battery cell housing is further reduced, and the compression thickness T2 of the outer ring 22 of this group of battery cell housings is 0.2 mm. After testing, it is found that the explosion-proof valve 1 of this group of battery cell housings is deformed even more at the position where it contacts the sealing ring 2. The reason is still that the compression thickness of the outer ring 22 is insufficient and cannot withstand the pressure from the first side wall 31 and the pressing member 4, so that the inner ring 21 is under excessive force and the explosion-proof valve 1 is deformed under force. Although the anti-pushing ability and anti-torsion ability of the pressing member 4 of this group of battery cell housings still meet the quality requirements, that is, the explosion-proof valve 1 is firmly connected at the first side wall 31, the helium leak detection yield rate of the explosion-proof valve 1 is further reduced and has dropped below 95%, and the appearance of the explosion-proof valve 1 does not meet the quality requirements even more. It can be seen that when the compression thickness of the second protruding ring 221 is insufficient, the probability of the explosion-proof valve 1 being deformed under force is relatively high.

[0076] In Comparative Example 6 in Table 2 above, the height h of the part where the second protruding ring 221 of the battery cell housing protrudes more than the first protruding ring 211 is greater than 0.3 mm, specifically 0.4 mm. The thickness of the first protruding ring 211 of this group of battery cell housings is too small, and the structural strength is insufficient and it is easy to be deformed by force. Moreover, due to the insufficient supporting force of the inner ring, the explosion-proof valve will be subjected to greater force and the explosion-proof valve will be deformed, resulting in poor assembly consistency between the explosion-proof valve and the sealing ring and a low sealing yield. After testing, the airtightness detection yield of this group of battery cell housings is lower than 97%.

[0077] In Comparative Example 7 in Table 2 above, the compression thickness T2 of the outer ring 22 of the battery cell housing is greater than 0.6 mm, and T2 is specifically 0.7 mm. The compression thickness of the outer ring 22 of this group of battery cell housings is too thick, it is difficult to position during riveting and press-fitting, and the compression reaction force is too large and it is easy to push open the riveting position of the press-fitting part 4, resulting in quality problems. After testing, the yield of this group of battery cell housings is lower than 95%.

[0078] It can be seen that when the battery cell housing meets the above more optimal value range, that is, the height h of the part where the second protruding ring 221 protrudes more than the first protruding ring 211, that is, the values of H1 - H2 in the table are all greater than 0 and less than or equal to 0.3 mm, the compression thickness T2 of the outer ring 22 all satisfies 0.35 mm ≤ T2 ≤ 0.6 mm, and the thickness T1 at the position where the explosion-proof valve 1 is not provided with a weak part is all greater than or equal to 0.5 mm, the airtightness at the explosion-proof valve 1 of the battery cell housing can meet the technical requirements. Moreover, there will be no deformation in the housing body 3 and the explosion-proof valve 1 of the battery cell housing, it is not easy to scrape when the electrode group is inserted into the housing, the anti-pushing ability and anti-twisting ability of the press-fitting part 4 also meet the quality requirements, the bursting value of the explosion-proof valve 1 also meets the requirements, and the overall yield of the battery cell will be greatly improved.

[0079] This embodiment also provides a battery cell, including a battery cell top cover, an electrode group, and the above-mentioned battery cell housing. The battery cell top cover is hermetically covered at the opening of the battery cell housing to form the outer shell of the battery cell, and the electrode group is arranged inside the outer shell. This battery cell can prevent the explosion-proof valve 1 and the housing body 3 from deforming and improve the process yield.

[0080] The explosion-proof valve 1 is no longer provided on the cell top cover of the cell, but is provided on the shell body 3 of the cell housing. When the cell undergoes thermal runaway, the path for valve opening and gas exhaust is shorter, so the cell has higher safety performance. Moreover, the cell adopts a design of using a press-fit part 4 to fix the explosion-proof valve 1, which can effectively improve the influence of welding on the explosion-proof valve 1, improve the product yield, and only need to rivet and weld the press-fit part 4 to the shell body 3 to fix the explosion-proof valve 1, eliminating the high-difficulty process step of welding the explosion-proof valve 1 to the first side wall 31. In the past, if the welding of the explosion-proof valve 1 was poor, the shell body 3 and the explosion-proof valve 1 had to be scrapped together. However, if the explosion-proof valve 1 is assembled poorly in the cell housing, the explosion-proof valve 1 can be replaced separately, and other components are not affected, which can reduce costs. At the same time, the cell housing is convenient for platform-based design and production, which can further improve production efficiency and reduce production costs. Through a more optimized size design, the cell can achieve a significant improvement in the yield of the cell manufacturing process.

[0081] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent replacements, 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. Battery cell housing, characterized in that, Comprising: An explosion-proof valve (1) having a weak part; A sealing ring (2) sleeved circumferentially at the edge of the explosion-proof valve (1); A housing body (3) having a first side wall (31) with a first explosion-proof through hole (311) formed therein; A press-fitting member (4) having a second explosion-proof through hole (41) formed therein, the press-fitting member (4) being riveted to the first side wall (31), the explosion-proof valve (1) being clamped between the press-fitting member (4) and the first side wall (31), and the sealing ring (2) being at least partially clamped circumferentially between the press-fitting member (4) and the first side wall (31) so that the press-fitting member (4) is in sealing butt joint with the first side wall (31), the projection of the weak part towards the first side wall (31) being located within the first explosion-proof through hole (311), and the projection of the weak part towards the press-fitting member (4) being located within the second explosion-proof through hole (41).

2. The cell housing according to claim 1, characterized in that The end face of the sealing ring (2) facing the first side wall (31) has a first protruding ring (211) and a second protruding ring (221) arranged coaxially, the second protruding ring (221) being arranged around the first protruding ring (211), the first protruding ring (211) covering the end face of the explosion-proof valve (1) facing the first side wall (31), and the first protruding ring (211) being partially clamped between the first side wall (31) and the press-fitting member (4), and the second protruding ring (221) being clamped between the press-fitting member (4) and the first side wall (31).

3. The cell housing according to claim 2, characterized in that, Axially along the sealing ring (2), the second protruding ring (221) protrudes more than the first protruding ring (211).

4. The cell housing according to claim 3, characterized in that, Axially along the sealing ring (2), the height h of the part where the second protruding ring (221) protrudes more than the first protruding ring (211) is less than or equal to 0.3 mm.

5. The battery cell housing according to any one of claims 1-4, characterized in that, The sealing ring (2) has an inner ring (21) and an outer ring (22) connected to each other, the inner ring (21) wrapping the edge of the explosion-proof valve (1), and the outer ring (22) being clamped between the first side wall (31) and the press-fitting member (4), and the compression thickness T2 of the outer ring (22) satisfies 0.35 mm ≤ T2 ≤ 0.6 mm.

6. The cell housing according to any one of claims 1-4, characterized in that, The sealing ring (2) has an inner ring (21), and the cross-section of the inner ring (21) is a C-shaped structure, the opening of the C-shaped structure facing the explosion-proof valve (1), and the C-shaped structure wrapping the edge of the explosion-proof valve (1).

7. The cell housing according to any one of claims 1-4, characterized in that, On the end face of the press-fitting part (4) facing the first side wall (31), a first sunk groove (42) and a second sunk groove (43) are formed. The second sunk groove (43) is formed at the bottom of the first sunk groove (42). The second explosion-proof through hole (41) is formed at the bottom of the second sunk groove (43). The sealing ring (2) has a connected inner ring (21) and outer ring (22). The inner ring (21) wraps the edge of the explosion-proof valve (1). The inner ring (21) is located in the second sunk groove (43). The outer ring (22) is clamped between the first side wall (31) and the bottom of the first sunk groove (42).

8. The battery cell housing according to any one of claims 1-4, characterized in that, On the first side wall (31), there is a riveting post (312). The riveting post (312) passes through the riveting hole (44) of the press-fitting part (4) and is riveted to the press-fitting part (4). The riveting post (312) is welded to the press-fitting part (4).

9. The cell housing according to any one of claims 1-4, characterized in that, The thickness T1 of the explosion-proof valve (1) at the position where the weak part is not provided satisfies T1≥0.5 mm.

10. The battery cell is characterized in that, It includes a battery cell top cover, a pole group, and the battery cell housing according to any one of claims 1-9. The battery cell top cover is hermetically covered at the opening of the battery cell housing to form the outer shell of the battery cell. The pole group is arranged inside the outer shell.

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