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 a shell body, an anti-explosion valve and a heat dissipation piece. Wherein a reinforcing boss is arranged on the first side wall of the shell body, and an anti-explosion through hole is formed in the middle of the reinforcing boss. The anti-explosion valve is arranged at the anti-explosion through hole to block the anti-explosion through hole, and the anti-explosion valve is welded to the reinforcing boss. And the heat dissipation piece is positioned at a back groove of the reinforcing boss. The structural strength of the shell body around the explosion-proof valve can be effectively enhanced by arranging the reinforcing boss, deformation of the shell body is prevented, heat dissipation can be enhanced by arranging the heat dissipation piece at the position of the groove in the back face, and the situation that deformation of the shell body is aggravated due to welding heat accumulation is further relieved. Due to the fact that the deformation problem is relieved, the welding difficulty can be reduced accordingly, and the welding yield is improved. The invention also provides a battery cell which comprises a pole group and the battery cell shell, and the pole group is positioned in the shell body. The battery cell can help to solve the problem of deformation and improve the welding yield of the explosion-proof valve.

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 the cell can effectively improve the safety of the cell. 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 housing is smaller, and in order to arrange the explosion-proof valve, an opening needs to be made on the housing, and the structural strength at the opening is further reduced. Therefore, the housing structure at the welding position of the explosion-proof valve is weak, and welding is likely to cause deformation of the housing, affecting the subsequent assembly and use of the cell. Moreover, the heat generated by welding the explosion-proof valve to the housing cannot be quickly dissipated, and the high-temperature environment will further exacerbate the deformation of the housing. The above problems will also lead to corresponding improvement in the welding process requirements, reduction in the production yield, increase in production costs, and reduction in production efficiency. Summary of the Invention

[0003] An object of the present invention is to provide a cell housing that can help solve the deformation problem and improve the welding yield of the explosion-proof valve.

[0004] To achieve this purpose, the present invention adopts the following technical solutions:

[0005] Provide a cell housing, including:

[0006] A housing body, on the first side wall of the housing body, there is a reinforcing boss, and an explosion-proof through hole is opened in the middle of the reinforcing boss;

[0007] An explosion-proof valve, the explosion-proof valve is arranged at the explosion-proof through hole to block the explosion-proof through hole, and the explosion-proof valve is welded to the reinforcing boss;

[0008] A heat dissipation member, the heat dissipation member is located at the back groove of the reinforcing boss.

[0009] Optionally, a limiting groove is opened on the protruding end face of the reinforcing boss, the explosion-proof through hole is opened at the bottom of the limiting groove, and the explosion-proof valve is located in the limiting groove.

[0010] Optionally, the thickness L of the reinforcing boss at the position where the limiting groove is not opened satisfies L > 0.8 mm;

[0011] And / or, the thickness K of the bottom of the limiting groove satisfies K > 0.3 mm.

[0012] Optionally, the explosion-proof valve is welded to the reinforcing boss along its circumferential direction to form a welded annular area. The heat dissipation member is in an annular sheet structure, and the projection of the welded annular area on the plane where the heat dissipation member is located completely falls within the heat dissipation member.

[0013] Optionally, the area S1 of the surface with the largest area of the annular sheet structure and the surface area S2 of the welded annular area satisfy S1 / S2≥0.35, and / or, S1 / S2≤0.7.

[0014] Optionally, the heat dissipation member is in an annular sheet structure, the annular sheet structure is attached to the bottom of the back groove, the thickness of the annular sheet structure is T, and the depth of the back groove is H, satisfying: H / T≥1, and / or, T>0.4mm.

[0015] Optionally, the heat dissipation member has a welding part, the welding part has a first layer and a second layer arranged in a stacked manner. The material of the first layer is the same as that of the first side wall, the first layer is welded to the first side wall, and the thermal conductivity of the material of the second layer is greater than that of the material of the first layer.

[0016] Optionally, both ends of the heat dissipation member in the length direction have the welding part.

[0017] Optionally, the first side wall is one of the two side walls of the shell body opposite to each other in its own width direction, and the reinforcing boss is located in the middle of the first side wall.

[0018] Another object of the present invention is to provide an electric core, which can help solve the problem of deformation of the shell body and improve the welding yield of the explosion-proof valve.

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

[0020] Provide an electric core, including a pole group and the above-mentioned electric core shell, and the pole group is located inside the shell body.

[0021] The beneficial effects of the present invention:

[0022] The present invention provides an electric core shell, including a shell body, an explosion-proof valve and a heat dissipation member. Among them, a reinforcing boss is provided on the first side wall of the shell body, and an explosion-proof through hole is opened in the middle of the reinforcing boss. The explosion-proof valve is arranged at the explosion-proof through hole to block the explosion-proof through hole, and the explosion-proof valve is welded to the reinforcing boss. The heat dissipation member is located at the back groove of the reinforcing boss. By providing the reinforcing boss, the structural strength of the shell body around the explosion-proof valve can be effectively enhanced, preventing the shell body from deforming. And by providing the heat dissipation member at the back groove, heat dissipation can be enhanced, further alleviating the aggravation of the deformation of the shell body caused by the accumulation of welding heat. Since the deformation problem is alleviated, the welding difficulty can be reduced accordingly, and the welding yield is improved.

[0023] The present invention also provides a battery core, comprising a pole group and the above-mentioned battery core shell, wherein the pole group is located in the shell body. The battery core helps to solve the deformation problem and can improve the welding yield of the explosion-proof valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is an exploded view of a battery cell housing provided by an embodiment of the present invention;

[0025] Figure 2 is a schematic structural diagram of a shell body provided by an embodiment of the present invention;

[0026] Figure 3 is a schematic structural diagram of a battery cell housing provided by an embodiment of the present invention;

[0027] Figure 4 yes Figure 3 Middle AA section view;

[0028] Figure 5 yes Figure 4 The enlarged view of point B in the middle;

[0029] Figure 6 is a schematic structural diagram of a heat sink provided by an embodiment of the present invention;

[0030] Figure 7 yes Figure 6 Middle CC section view;

[0031] Figure 8 It is a schematic diagram of the structure of a battery cell provided by an embodiment of the present invention.

[0032] In the figure:

[0033] 1. Shell body; 11. First side wall; 12. Strengthening boss; 121. Protruding end surface; 122. Limiting groove; 1221. Explosion-proof through hole; 123. Back groove;

[0034] 2. Explosion-proof valve; 3. Heat dissipation component; 31. Welding part; 311. First layer; 312. Second layer;

[0035] 10. Welding annular area; 100. Battery cell shell; 200. Battery cell top cover. DETAILED DESCRIPTION

[0036] Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the above drawings.

[0037] In this application, the terms "comprise", "include", "have" or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising 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 apparatus. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising that element.

[0038] In this application, the term "and / or" describes the relationship between associated objects and indicates that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, in this application, the character " / " generally indicates that the objects before and after are in an "and / or" relationship.

[0039] In this application, the terms "connect", "combine", "couple", "mount" may be direct connections, combinations, couplings or mounts, or may be indirect connections, combinations, couplings or mounts. 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 each connected to at least one intermediate member, and these two parts or components are connected through the intermediate member. In addition, "connect" and "couple" are not limited to physical or mechanical connections or couplings and may include electrical connections or couplings.

[0040] 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 stated 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, etc. associated with a particular value. Such terms should also be considered to disclose a range defined by the absolute values of two endpoints. Relative terms may refer to a plus or minus a certain percentage (such as 1%, 5%, 10% or more) of the indicated value. A numerical value without the use of a relative term should also be disclosed as a particular value having a tolerance. 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) from the indicated angle.

[0041] In this application, those of ordinary skill in the art will understand that the functions performed by a component may be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by a part may also be performed by one part, one component, or a combination of multiple parts.

[0042] In this application, the orientation terms such as "upper", "lower", "left", "right", "front", and "back" 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 component is connected "above" or "below" another component, it can not only be directly connected "above" or "below" another component, but also be indirectly connected "above" or "below" another component through an intermediate component. It should also be understood that the orientation terms such as the upper side, the lower side, the left side, the right side, the front side, and the back side not only represent the positive orientation, but can also be understood as the side orientation. For example, the lower side can include directly below, lower left, lower right, lower front, and lower back, etc.

[0043] Setting an explosion-proof valve on the battery cell can effectively improve the safety of the battery cell. 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 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 housing is smaller, and in order to arrange the explosion-proof valve, an opening needs to be made on the housing, and the structural strength at the opening is further reduced. Therefore, the structure of the housing at the welding position of the explosion-proof valve is weak, and welding is likely to cause deformation of the housing, affecting the subsequent assembly and use of the battery cell. Moreover, the heat generated by welding the explosion-proof valve to the housing cannot be dissipated quickly, and the high-temperature environment will further exacerbate the deformation of the housing. The above problems will also lead to a corresponding increase in the requirements for the welding process, a decrease in the production yield, an increase in the production cost, and a decrease in the production efficiency.

[0044] Therefore, this embodiment provides a battery cell housing 100, which can help solve the deformation problem and improve the welding yield of the explosion-proof valve 2.

[0045] As Figure 1 - Figure 7 shown, the battery cell housing 100 of this embodiment includes a housing body 1, an explosion-proof valve 2, and a heat dissipation member 3. Among them, a reinforcing boss 12 is provided on the first side wall 11 of the housing body 1, and an explosion-proof through hole 1221 is opened in the middle of the reinforcing boss 12. The explosion-proof valve 2 is arranged at the explosion-proof through hole 1221 to block the explosion-proof through hole 1221, and the explosion-proof valve 2 is welded to the reinforcing boss 12. The heat dissipation member 3 is located at the back groove 123 of the reinforcing boss 12. By providing the reinforcing boss 12, the structural strength of the housing body 1 around the explosion-proof valve 2 can be effectively enhanced, preventing the housing body 1 from deforming. By providing the heat dissipation member 3 at the back groove 123, heat dissipation can be enhanced, further alleviating the aggravation of the deformation of the housing body 1 caused by the accumulation of welding heat. Since the deformation problem is alleviated, the welding difficulty can be reduced accordingly, and the welding yield is improved.

[0046] Optionally, a limiting groove 122 is provided on the protruding end face 121 of the reinforcing boss 12, and an explosion-proof through hole 1221 is provided at the bottom of the limiting groove 122. The explosion-proof valve 2 is located in the limiting groove 122, which is convenient for positioning during the assembly of the explosion-proof valve 2. Optionally, in this embodiment, the reinforcing boss 12 is located on the outer wall surface of the first side wall 11, that is, the protruding end face 121 faces the outside of the battery cell.

[0047] As Figure 5 shown, optionally, the thickness L of the part of the reinforcing boss 12 where the limiting groove 122 is not provided satisfies L > 0.8 mm. When the thickness L of the part of the reinforcing boss 12 where the limiting groove 122 is not provided is less than or equal to 0.8 mm, the reinforcing effect of the reinforcing boss 12 on the structure is not good, and the housing body 1 still deforms after welding the explosion-proof valve 2. And the limiting groove 122 is provided in the middle of the protruding end face 121, that is, the limiting groove 122 does not fit the edge of the protruding end face 121, so that it can be ensured that along the circumferential direction of the explosion-proof valve 2, there is a part with a thickness of L around the explosion-proof valve 2 everywhere on the reinforcing boss 12, so as to block the deformation caused by welding from extending in any direction, and it can be ensured that the first side wall 11 and the adjacent side walls do not deform. Optionally, the centers of the reinforcing boss 12, the limiting groove 122, the explosion-proof through hole 1221 and the explosion-proof valve 2 coincide.

[0048] Optionally, the thickness K of the bottom of the limiting groove 122 satisfies K > 0.3 mm. Similarly, since the thickness of the welding area of the explosion-proof valve 2 is generally in the range of 0.4 mm - 0.5 mm, when the thickness K of the bottom of the limiting groove 122 is less than or equal to 0.3 mm, its own structural strength is insufficient to support the explosion-proof valve 2, and even when the internal pressure of the battery cell is too high, the bottom of the limiting groove 122 is prone to deformation. Moreover, when the thickness K of the bottom of the limiting groove 122 is less than or equal to 0.3 mm, since the explosion-proof valve 2 cannot protrude from the limiting groove 122, the thickness of the reinforcing boss 12 around the explosion-proof valve 2 will be less than or equal to 0.8 mm, thus affecting the deformation blocking effect.

[0049] As Figure 3 and Figure 5 shown, optionally, the explosion-proof valve 2 is welded to the reinforcing boss 12 along its circumferential direction to form a welding annular region 10. The heat dissipation member 3 is an annular sheet structure, and the projection of the welding annular region 10 on the plane where the heat dissipation member 3 is located completely falls within the heat dissipation member 3 to ensure that the path for the welding heat to be transferred to the heat dissipation member 3 is the shortest, which is beneficial to improving the heat dissipation efficiency.

[0050] Optionally, the surface with the largest area of the annular sheet structure is the Figure 6 annular surface shown in, and this annular surface adheres to the bottom of the back groove 123, and the area of this annular surface is S1. The surface of the welding annular region 10 is the Figure 3The annular surface shown, the area of the annular surface is S2. S1 and S2 satisfy S1 / S2≥0.35. When the ratio of S1 to S2 is less than 0.35, that is, the surface of the largest area of the heat dissipation member 3 is too large, or the surface of the welding annular region 10 is too small. And since the size of the surface of the largest area of the heat dissipation member 3 is limited by the dimensions of the first side wall 11 and the back groove 123 and cannot be too large, only the surface of the welding annular region 10 can be reduced, which easily leads to problems such as poor welding and unqualified sealing performance.

[0051] Optionally, S1 / S2≤0.7. When the ratio of S1 to S2 is greater than 0.7, that is, the difference between the two is small. When the surface area of the welding annular region 10 is certain, the size of the surface of the largest area of the heat dissipation member 3 is insufficient, which will affect the heat dissipation effect of the heat dissipation member 3, and the heat cannot be dissipated in time, and the problem of deformation of the shell body 1 cannot be completely solved.

[0052] As Figure 5 and Figure 7 shown, optionally, the heat dissipation member 3 is an annular sheet structure, the annular sheet structure is attached to the bottom of the back groove 123, the thickness of the annular sheet structure is T, and the depth of the back groove 123 is H, satisfying: H / T≥1, that is, the heat dissipation member 3 needs to be completely located within the back groove 123, and there should be no protruding positions, otherwise the heat dissipation member 3 will interfere with the insertion of the electrode group into the shell, causing problems such as scraping and damage to the electrode group.

[0053] Optionally, the thickness T of the annular sheet structure is >0.4 mm to ensure that the thickness of the heat dissipation member 3 is sufficient. If the thickness of the annular sheet structure is too small, on the one hand, it will increase the processing difficulty, and on the other hand, it is not conducive to the structural strength of the heat dissipation member 3. The heat dissipation member 3 is thermally deformed and does not adhere to the bottom of the back groove 123, which will also affect the heat dissipation effect of the heat dissipation member 3.

[0054] As Figure 7 shown, optionally, the heat dissipation member 3 has a welding portion 31, the welding portion 31 has a first layer 311 and a second layer 312 arranged in a stacked manner. The material of the first layer 311 is the same as that of the first side wall 11. The first layer 311 is attached to the bottom of the back groove 123, and the first layer 311 is welded to the first side wall 11. Welding with the same material has better welding quality. Optionally, the materials of the first layer 311 and the shell body 1 are both aluminum. The thermal conductivity coefficient of the material of the second layer 312 is greater than that of the material of the first layer 311 to improve the thermal conduction and heat dissipation efficiency of the heat dissipation member 3 when the thickness of the heat dissipation member 3 is certain. Optionally, the material of the second layer 312 is copper, and the thermal conductivity coefficient of copper is greater than that of aluminum.

[0055] Optionally, both ends of the heat dissipation member 3 in the length direction are provided with welding portions 31 to ensure that the heat dissipation member 3 is firmly welded to the housing body 1. Optionally, the remaining part of the heat dissipation member 3 is made of copper to improve the heat dissipation efficiency of the heat dissipation member 3 as much as possible while ensuring that the heat dissipation member 3 is firmly connected to the housing body 1.

[0056] Optionally, the first side wall 11 is one of the two side walls of the housing body 1 arranged oppositely in its own width direction, and the reinforcing boss 12 is located in the middle of the first side wall 11 to ensure the shortest exhaust path and improve the safety of the battery cell.

[0057] To verify whether the battery cell housing 100 designed above can prevent the deformation of the housing body 1 while ensuring the welding yield of the explosion-proof valve 2, this embodiment provides a set of experimental data for corroboration. Table 1 below lists the size parameters of the battery cell housings 100 of six groups of examples, and Table 2 lists the size parameters of the battery cell housings 100 of five groups of comparative examples. These eleven groups of battery cell housings 100 have some identical configurations. For example, the material of their explosion-proof valves 2 is MXF2, the length of the explosion-proof valve 2 is 68 mm, the width is 15 mm, the groove depth H of the back groove 123 is 0.8 mm, and the housing body 1 is formed by stamping.

[0058] Table 1

[0059] Category Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 L (mm) 1 1 1 1 1 1 H (mm) 0.8 0.8 0.8 0.8 0.8 0.8 T (mm) 0.5 0.55 0.6 0.65 0.7 0.8 H / T 1.60 1.45 1.33 1.23 1.14 1.00 <![CDATA[S1(mm 2 )]]> 408.60 408.60 408.60 408.60 408.60 408.60 <![CDATA[S2(mm 2 )]]> 142.5 167.6 195.4 238.2 259.7 287.2 S2 / S1 0.35 0.41 0.48 0.58 0.64 0.70

[0060] Table 2

[0061] Category Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 L (mm) 1 1 1 1 0.8 H (mm) 0.8 0.8 0.8 0.8 0.8 T (mm) 0.4 0.45 0.85 0.9 0.7 H / T 2.00 1.78 0.94 0.89 1.14 <![CDATA[S1(mm 2 )]]> 408.60 408.60 408.60 408.60 408.60 <![CDATA[S2(mm 2 )]]> 135.30 298.10 259.70 259.7 259.7 S2 / S1 0.33 0.73 0.64 0.64 0.64

[0062] The six groups of battery cell housings 100 of Examples 1 to 6 all meet the above-mentioned better size range. The thickness L at the place where the limiting groove 122 is not provided on the reinforcing boss 12 all satisfies L > 0.8 mm. The area S1 of the surface with the largest area of the heat dissipation member 3 and the surface area S2 of the welding annular region 10 satisfy S1 / S2 ≥ 0.35 and S1 / S2 ≤ 0.7. The thickness T of the heat dissipation member 3 and the groove depth H of the back groove 123 satisfy: H / T ≥ 1 and T > 0.4 mm. There is no abnormal concave deformation at the welding position of the explosion-proof valve 2 on the housing body 1 of these six groups of battery cell housings 100. Abnormal concave deformation is deformation with a concave depth less than 0.4 mm. The welding quality of the explosion-proof valve 2 meets the technical requirements, the helium leak detection results are all normal, there is no air leakage problem, and the welding yield reaches 100%. It can be seen that the battery cell housing 100 that meets the above design dimensions can completely solve the problem of deformation of the housing body 1 while ensuring the welding yield of the explosion-proof valve 2 and improve the quality of the battery cell.

[0063] The ratio of the area S1 of the largest-area surface of the heat dissipation member 3 of the battery cell housing 100 of Comparative Example 1 to the surface area S2 of the welding annular region 10 is 0.33, that is, S1 / S2 < 0.35. Due to the limitation of the sizes of the first side wall 11 and the reinforcing boss 12, the area S1 of the largest-area surface of the heat dissipation member 3 of the battery cell housing 100 cannot be too large. Therefore, for the battery cell housing 100 of this group, the surface area S2 of the welding annular region 10 is only 135.3 mm 2 , and the value of S2 is too small, resulting in insufficient welding quality. After detecting this group of battery cell housings 100, it is found that there is no over-tolerance concave deformation at the welding position of the explosion-proof valve 2 on the housing body 1 of this group of battery cell housings 100. Over-tolerance concave deformation refers to the deformation with an inner concave depth greater than 0.4 mm. However, the effective welding penetration depth of the explosion-proof valve 2 of this battery cell housing 100 is insufficient, there is a problem of false welding, the welding quality is unstable, helium leak detection shows air leakage, and the overall yield is less than 98%.

[0064] The ratio of the area S1 of the largest-area surface of the heat dissipation member 3 of the battery cell housing 100 of Comparative Example 2 to the surface area S2 of the welding annular region 10 is 0.73, that is, S1 / S2 > 0.7. The size of the heat dissipation member 3 of this group is insufficient, and the heat dissipation effect is not good. After detecting this group of battery cell housings 100, it is found that the welding quality of the explosion-proof valve 2 of this group of battery cell housings 100 meets the technical requirements, the helium leak detection results are all normal, and there is no air leakage problem. However, the housing body 1 of this group of battery cell housings 100 has over-tolerance concave deformation at the welding position of the explosion-proof valve 2, the appearance of the battery cell housing 100 is abnormal, the resistance of the electrode group entering the housing is large, and there is a risk of scratching the inner insulating film, and the quality of the battery cell is not good. However, compared with the battery cell housing 100 in the prior art without the reinforcing boss 12 and the heat dissipation member 3, the deformation depth of the battery cell housing 100 of Comparative Example 2 is smaller and the deformation area is smaller. Therefore, the deformation problem is alleviated to some extent.

[0065] The ratio of the thickness T of the heat dissipation member 3 of the battery cell housing 100 of Comparative Example 3 to the groove depth H of the back groove 123 is 0.94, that is, H / T is less than 1. After detecting this group of battery cell housings 100, it is found that there is no over-tolerance concave deformation at the welding position of the explosion-proof valve 2 on the housing body 1 of this group of battery cell housings 100, and the welding quality of its explosion-proof valve 2 meets the technical requirements, and the helium leak detection results are all normal, and there is no air leakage problem. However, since the heat dissipation member 3 protrudes from the back groove 123, that is, the heat dissipation member 3 protrudes into the inner cavity of the housing body 1, there are problems such as the heat dissipation member 3 scratching the electrode group and scratching the inner insulating film when the electrode group enters the housing.

[0066] For the cell housing 100 of Comparative Example 4, the ratio of the thickness T of the heat dissipation member 3 to the groove depth H of the back groove 123 is 0.89, that is, H / T is further reduced. After detecting this group of cell housings 100, it is found that the shell body 1 of this group of cell housings 100 does not show excessive concave deformation at the welded explosion-proof valve 2, and the welding quality of its explosion-proof valve 2 meets the technical requirements, and the helium leak detection results are all normal, and there is no air leakage problem. However, since the heat dissipation member 3 protrudes from the back groove 123, that is, the heat dissipation member 3 protrudes into the inner cavity of the shell body 1, when the electrode group is inserted into the shell, problems such as the heat dissipation member 3 scratching the electrode group and the inner insulating film being scratched occur, and the proportion of problems is higher than that of Comparative Example 3.

[0067] For the cell housing 100 of Comparative Example 5, the thickness L of the reinforcing boss 12 where the limiting groove 122 is not opened is 0.8 mm, that is, the thickness of the reinforcing boss 12 around the welding annular region 10 is insufficient, its structural strength is insufficient, and its effect of blocking deformation is not good. After detecting this group of cell housings 100, it is found that the shell body 1 of this group of cell housings 100 shows excessive concave deformation at the welded explosion-proof valve 2, and due to the influence of the deformation, the welding yield of the explosion-proof valve 2 of this group of cell housings 100 is lower than 98%.

[0068] This embodiment also provides a battery cell, including an electrode group and the above-mentioned cell housing 100, and the electrode group is located inside the shell body 1. The battery cell further includes a cell top cover 200, and the cell top cover 200 is covered at the opening at one end of the cell housing 100 along its own length direction, and the cell top cover 200 is hermetically connected to the cell housing 100.

[0069] In the battery cell provided in this embodiment, the explosion-proof valve 2 is no longer arranged on the cell top cover 200, but on the shell body 1 of the cell housing 100. When the battery cell is thermally out of control, the path of opening the valve for exhaust is shorter, which is beneficial to improving the safety performance of the battery cell. Moreover, by adopting a boss structure at the explosion-proof through hole 1221 of the shell body 1, the mechanical strength at the explosion-proof through hole 1221 can be enhanced, and the deformation of the shell body 1 caused by welding can be alleviated. And by adding the heat dissipation member 3 at the back groove 123, the heat dissipation effect can be achieved without affecting the assembly of the electrode group, and the deformation problem of the shell body 1 caused by welding heat can be further alleviated. By adopting a more optimized design scheme, that is, the thickness L of the reinforcing boss 12 where the limiting groove 122 is not opened satisfies L>0.8 mm, the area S1 of the surface with the largest area of the heat dissipation member 3 and the surface area S2 of the welding annular region 10 satisfy S1 / S2≥0.35 and S1 / S2≤0.7, and the thickness T of the heat dissipation member 3 and the groove depth H of the back groove 123 satisfy H / T≥1 and T>0.4 mm, the cell housing 100 can completely solve the problem of shell deformation caused by welding and improve the process yield of the battery cell.

[0070] 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 implementation manners here. Any modifications, equivalent substitutions, improvements, etc. 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. The battery cell housing, characterized in that, Comprising: A shell body (1), on the first side wall (11) of the shell body (1) there is a reinforcing boss (12), and in the middle of the reinforcing boss (12) there is an explosion-proof through hole (1221); An explosion-proof valve (2), the explosion-proof valve (2) is arranged at the explosion-proof through hole (1221) to block the explosion-proof through hole (1221), and the explosion-proof valve (2) is welded to the reinforcing boss (12); A heat dissipation member (3), the heat dissipation member (3) is located at the back groove (123) of the reinforcing boss (12).

2. The cell housing according to claim 1, wherein, On the protruding end face (121) of the reinforcing boss (12) there is a limiting groove (122), at the bottom of the limiting groove (122) there is the explosion-proof through hole (1221), and the explosion-proof valve (2) is located in the limiting groove (122).

3. The cell housing according to claim 2, characterized in that, The thickness L of the part of the reinforcing boss (12) where the limiting groove (122) is not opened satisfies L > 0.8 mm; And / or, the thickness K of the bottom of the limiting groove (122) satisfies K > 0.3 mm.

4. The cell housing according to claim 1, wherein The explosion-proof valve (2) is welded to the reinforcing boss (12) along its circumferential direction to form a welded annular area (10), the heat dissipation member (3) is an annular sheet structure, and the projection of the welded annular area (10) on the plane where the heat dissipation member (3) is located completely falls within the heat dissipation member (3).

5. The cell housing according to claim 4, characterized in that, The area S1 of the surface with the largest area of the annular sheet structure and the surface area S2 of the welded annular area (10) satisfy S1 / S2 ≥ 0.35, and / or, S1 / S2 ≤ 0.

7.

6. The cell housing according to any one of claims 1-5, characterized in that, The heat dissipation member (3) is an annular sheet structure, the annular sheet structure adheres to the bottom of the back groove (123), the thickness of the annular sheet structure is T, and the depth of the back groove (123) is H, satisfying: H / T ≥ 1, and / or, T > 0.4 mm.

7. The cell housing according to any one of claims 1-5, characterized in that, The heat dissipation member (3) has a welding part (31), the welding part (31) has a first layer (311) and a second layer (312) arranged in a stacked manner, the material of the first layer (311) is the same as the material of the first side wall (11), the first layer (311) is welded to the first side wall (11), and the thermal conductivity of the material of the second layer (312) is greater than the thermal conductivity of the material of the first layer (311).

8. The cell housing according to claim 7, wherein, Both ends of the heat dissipation member (3) along the length direction have the welding part (31).

9. The cell housing according to any one of claims 1-5, characterized in that, The first side wall (11) is one of the two side walls of the shell body (1) arranged oppositely along its own width direction, and the reinforcing boss (12) is located in the middle of the first side wall (11).

10. The battery cell is characterized in that, Comprising a pole group and a battery cell housing according to any one of claims 1-9, the pole group is located inside the shell body (1).

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