Housing and battery cell

Abstract

The utility model relates to battery technical field discloses shell and electric core. Shell, include: multiple side walls, multiple side walls are connected head to tail in proper order to enclose and form the accommodating cavity, form transition fillet at the connecting place of two adjacent side walls and set up the avoidance slot at transition fillet, the avoidance slot is at least by the surface recess of transition fillet's side to the accommodating cavity, along the radial direction of transition fillet, the wall thickness between the groove wall of the avoidance slot and the side of transition fillet away from the accommodating cavity is t0, wherein, one of two adjacent side walls is first side wall and the other is second side wall, along the wall thickness direction of first side wall, the bottom of avoidance slot is located between the inner wall and the outer wall of first side wall, the wall thickness of second side wall is t2, the value range of t0 is: 0.3mm <= t0 <= t2. While guaranteeing that there is no interference between pole group and shell, it is favorable to promote the energy density of electric core, and still has enough structural strength after setting up the avoidance slot of shell.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to the casing and the battery cell. Background Technology

[0002] A battery cell includes a housing, a cover assembly, and electrode assemblies. The electrode assemblies are located inside the housing, and the cover assembly covers the open end of the housing. In existing battery cells, the junctions between adjacent walls inside the housing are typically rounded for transition. To prevent interference between the corners formed at the junctions of different surfaces of the electrode assemblies and the rounded corners inside the housing, which could damage the electrode assemblies, a support plate is usually placed between at least one wall of the housing and the electrode assemblies to increase the distance between them. However, because the support plate occupies space inside the housing, it reduces the size of the electrode assemblies, thus reducing the energy density of the battery cell. Therefore, existing battery cells cannot simultaneously achieve both no interference between the electrode assemblies and the housing and a high energy density. Utility Model Content

[0003] In view of this, the present invention provides a housing and a battery cell to solve the problem that the battery cell cannot simultaneously achieve no interference between the electrode assembly and the housing and have a high energy density.

[0004] In a first aspect, this utility model provides a housing, comprising: multiple sidewalls connected end-to-end to form a receiving cavity; a transition fillet is formed at the junction of two adjacent sidewalls, and a clearance groove is provided at the transition fillet; the clearance groove is formed by at least the surface of the transition fillet facing the receiving cavity; along the radial direction of the transition fillet, the wall thickness between the side of the transition fillet away from the receiving cavity and the groove wall of the clearance groove is t0; wherein, one of the two adjacent sidewalls is a first sidewall and the other is a second sidewall; along the wall thickness direction of the first sidewall, the bottom of the clearance groove is located between the inner and outer walls of the first sidewall; the wall thickness of the second sidewall is t2, and the value range of t0 is: 0.3 mm ≤ t0 ≤ t2.

[0005] Beneficial effects: By setting clearance grooves at the connection points of two adjacent sidewalls on the casing, and with the clearance grooves located inside the casing, a clearance space is formed at the transition fillet position at the connection point of the two adjacent sidewalls to avoid interference with the edge of the electrode assembly. This allows the electrode assembly to avoid interference with the transition fillet without adding side plates or reducing the size of the electrode assembly itself during assembly. This ensures no interference between the electrode assembly and the casing, while improving the utilization rate of the internal space of the cell, which is beneficial to increasing the energy density of the cell. At the same time, by limiting the wall thickness t0 of the part of the casing corresponding to the clearance groove to no greater than the wall thickness t2 of the second sidewall and no less than 0.3 mm, it can be ensured that the clearance groove can provide effective clearance for the electrode assembly, avoiding interference between the electrode assembly and the casing, and ensuring smooth processing and forming of the casing. It can also ensure that the casing still has sufficient structural strength after setting the clearance groove, thereby ensuring the safety of the cell.

[0006] In one optional embodiment, the wall thickness t2 of the second sidewall is in the range of 0.5 mm ≤ t2 ≤ 1.5 mm.

[0007] Beneficial effects: It can ensure that the second sidewall has sufficient structural strength, thereby ensuring the safety of the battery cell, and can also avoid excessive weight of the casing, which is conducive to reducing costs and improving the energy density of the battery cell.

[0008] In one optional embodiment, the groove wall of the clearance groove includes a first arc-shaped surface and a connecting surface. The first arc-shaped surface is connected to the inner wall of the second side wall, and the connecting surface is connected between the first arc-shaped surface and the inner wall of the first side wall. The connecting surface has a first side connected to the inner wall of the first side wall and a second side connected to the first arc-shaped surface. Along a direction perpendicular to the inner wall of the second side wall, the distance from the first side to the inner wall of the second side wall is L1, and the distance from the second side to the inner wall of the second side wall is L2, wherein L1≥L2.

[0009] Beneficial effects: By setting the groove wall of the clearance groove to include at least a first arc-shaped surface and a connecting surface, the first arc-shaped surface is adapted to the transition fillet, and the distance from the connection position of the connecting surface and the inner wall of the first side wall to the second side wall is greater than the distance from the connection position of the connecting surface and the first arc-shaped surface to the second side wall, the opening of the clearance groove gradually expands towards the receiving cavity, which facilitates the processing and forming of the clearance groove, and can increase the size of the clearance groove, maximize the clearance space, and reduce the risk of interference between the pole group and the transition fillet.

[0010] In one optional embodiment, the connecting surface is set at an angle to the inner wall of the first sidewall, and the angle between the extended surface of the connecting surface and the inner wall of the first sidewall is θ. The first sidewall is a large surface of the shell, wherein 10°≤θ≤90°; or, the first sidewall is a narrow surface of the shell, wherein 25°≤θ≤90°.

[0011] Beneficial effects: When the first sidewall is a large surface of the shell, by limiting the angle between the extended surface of the connecting surface and the inner wall of the first sidewall to a value within the range of 10° to 90°, it is possible to ensure that the clearance groove can be formed smoothly, improving the shell forming yield, and also to ensure that the first sidewall has sufficient support area for the electrode group, improving the stability of the electrode group, thereby improving the vibration and shock resistance of the cell; or, when the first sidewall is a narrow surface of the shell, by limiting the angle between the extended surface of the connecting surface and the inner wall of the narrow surface of the shell to a value within the range of 25° to 90°, it is possible to ensure that the clearance groove can be formed smoothly, improving the shell forming yield, and also to ensure that the first sidewall has sufficient support area for the electrode group, improving the stability of the electrode group, thereby improving the vibration and shock resistance of the cell.

[0012] In one optional embodiment, the groove wall of the clearance groove further includes a planar area, which is connected between the first arcuate surface and the connecting surface, and the planar area is parallel to the inner wall of the first sidewall.

[0013] Beneficial effects: By adding a planar area between the first arc-shaped surface and the connecting surface, the area occupied by the clearance groove on the first side wall is increased, which further ensures that the clearance groove can provide effective clearance space for the electrode group, and facilitates the processing and forming of the clearance groove. It can also reduce the stress concentration problem during the shell forming process, avoid the risk of deformation or cracking caused by excessive local stress, and thus improve the safety of the battery cell.

[0014] In one alternative embodiment, the thickness of the first sidewall is t along the wall thickness direction of the first sidewall, and the distance between the planar region and the outer wall of the first sidewall is t1, wherein 0.3≤t1 / t≤0.95.

[0015] Beneficial effects: It can ensure that the first sidewall has sufficient structural strength to prevent the shell from tearing and ensure the safety of the battery cell. It can also provide sufficient clearance space for the electrode group in the clearance slot, avoid interference between the electrode group and the transition radius of the shell, and ensure normal assembly and use of the battery cell.

[0016] In one optional implementation, the value of t1 is in the range of: t1≥0.3 mm; And / or, the range of t is: 0.8 mm ≤ t ≤ 2 mm.

[0017] Beneficial effects: By limiting t1 to greater than or equal to 0.3 mm, the casing 10 can be guaranteed to have sufficient structural strength to prevent casing tearing and ensure the safety of the battery cell; And / or, by limiting t to a value within the range of 0.8 mm to 2 mm, it is possible to ensure that the casing 10 has sufficient strength to protect the internal structure of the battery cell, while also controlling the overall weight and volume of the battery cell, which is beneficial to improving the energy density of the battery cell and achieving miniaturization.

[0018] In one optional embodiment, the intersection line of the extended surface of the inner wall of the first sidewall and the extended surface of the inner wall of the second sidewall extends along the Z direction, the clearance groove extends along the Z direction, and the size of the planar area is L in the direction perpendicular to the Z direction within the planar area, wherein 0≤L≤10 mm. And / or, the connecting surface and the planar area are connected by a second arc-shaped surface.

[0019] Beneficial effects: By limiting the width of the planar area to between 0 and 10 mm, it is possible to avoid the clearance slot occupying too much space on the first sidewall, thereby ensuring that the first sidewall has sufficient support area for the electrode group, improving the stability of the electrode group, and thus improving the overall performance of the cell. And / or, by setting a second arc-shaped surface between the planar area and the connecting surface, a smooth transition is achieved between the connecting surface and the planar area, avoiding sharp corners, effectively alleviating stress concentration at the junction of the connecting surface and the planar area, thereby significantly enhancing the fatigue resistance of the shell, preventing deformation or even cracking of the shell during manufacturing or use, and improving the safety of the shell.

[0020] In one optional implementation, the radius of the first arcuate surface is R, where 0.5 mm ≤ R ≤ 4 mm; And / or, the connecting surface is connected to the inner wall of the first sidewall via a third arc-shaped surface.

[0021] Beneficial effects: By limiting R to a value within the range of 0.5 mm to 4 mm, it is possible to ensure that the clearance slot has a suitable opening size, providing sufficient clearance space for the edge of the pole group and avoiding interference damage between the pole group and the transition fillet. At the same time, it is possible to avoid the clearance slot occupying too much space, ensuring that the first sidewall has sufficient support area for the pole group, improving the stability of the pole group, and thus improving the overall performance of the cell. And / or, by providing a third arc-shaped surface between the connecting surface and the inner wall of the first sidewall for a smooth transition, sharp corners are avoided at the connection between the connecting surface and the inner wall of the first sidewall, preventing sharp corners from cutting the electrode assembly, thereby improving the safety performance of the battery cell.

[0022] Secondly, this utility model also provides a battery cell, comprising: the aforementioned housing; and an electrode assembly disposed within a receiving cavity of the housing. Since the battery cell includes the housing and has the same effects as the housing, it will not be described further here. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a battery cell before the improvement. Figure 2 for Figure 1 A cross-sectional view along the CC direction; Figure 3 for Figure 2 A magnified view of part A in the diagram; Figure 4 This is a schematic diagram of the structure of a shell according to an embodiment of the present utility model; Figure 5 for Figure 4 The cross-sectional view of the shell shown; Figure 6 This is a partially enlarged cross-sectional view of a shell according to an embodiment of the present utility model; Figure 7 This is a partially enlarged cross-sectional view of another shell according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures: 10. Housing; 11. Sidewall; 111. First sidewall; 1111. First inner wall; 1112. First outer wall; 112. Second sidewall; 12. Transition fillet; 13. Clearance groove; 14. Receiving cavity; 131. First arc-shaped surface; 132. Connecting surface; 133. Planar area; 134. Second arc-shaped surface; 135. Third arc-shaped surface; 136. Fourth arc-shaped surface; 20. Electrode assembly; 21. Insulating film; 30. Cover plate assembly; 40. Side plate. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0027] like Figures 1 to 3As shown, the housing 10 of a conventional blade battery cell (a cell with openings at both ends) is typically surrounded by four sidewalls 11. A transition fillet 12 is formed at the intersection of adjacent sidewalls 11. The four sidewalls 11 include two large surfaces facing each other along the X direction and two narrow surfaces facing each other along the Y direction. To avoid interference between the electrode and the transition fillet 12, which could damage the electrode, a side plate 40 is typically provided at least inside the narrow surface. The side plate 40 is supported between the electrode assembly and the narrow surface of the housing. However, the side plate 40 occupies internal space in the housing, reducing the size of the electrode assembly and affecting the improvement of the cell's energy density. Furthermore, unlike prismatic cells, blade cells have a longer dimension along the Z direction. When the electrode assembly 20 is assembled into the housing 10, interference can easily occur between the insulating film 21 wrapped around the outside of the electrode assembly 20 and the transition fillet 12 of the housing, leading to a decrease in yield. In other words, existing battery technologies struggle to simultaneously achieve both no interference between the electrode assembly and the housing and a high energy density. The X, Y, and Z directions are as follows: Figures 1 to 5 As shown by the middle arrow, the X, Y, and Z directions intersect in pairs.

[0028] The following is combined Figures 4 to 7 The following describes embodiments of the present invention.

[0029] According to an embodiment of the present invention, a housing is provided, comprising: a plurality of sidewalls 11 connected end to end to form a receiving cavity 14, a transition fillet 12 is formed at the connection between two adjacent sidewalls 11, and a relief groove 13 is provided at the transition fillet 12, the relief groove 13 being formed by at least the surface of the transition fillet 12 facing the receiving cavity 14 being recessed, and the wall thickness between the side of the transition fillet 12 away from the receiving cavity 14 and the groove wall of the relief groove 13 along the radial direction of the transition fillet 12 is t0; wherein, one of the two adjacent sidewalls 11 is a first sidewall 111 and the other is a second sidewall 112, and the bottom of the relief groove 13 is located between the inner wall and the outer wall of the first sidewall 111 along the wall thickness direction of the first sidewall 111; the wall thickness of the second sidewall 112 is t2, and the value range of t0 is: 0.3 mm ≤ t0 ≤ t2.

[0030] It should be noted that a transition fillet 12 is formed at the connection between any two adjacent sidewalls 11, and the clearance groove 13 at least covers the entire surface of the transition fillet 12 facing the receiving cavity 14; the inner wall of the first sidewall 111 refers to the wall surface of the first sidewall 111 facing the receiving cavity 14 (i.e., the first inner wall 1111), and the outer wall of the first sidewall 111 refers to the wall surface of the first sidewall 111 facing away from the receiving cavity 14 (i.e., the first outer wall 1112). The bottom of the clearance groove 13 is located between the first inner wall 1111 and the first outer wall 1112; the bottom of the clearance groove 13 refers to the position on the groove wall of the clearance groove 13 that is farthest from the inner wall of the first sidewall 111 along the wall thickness direction of the first sidewall 111, such as... Figures 6 to 7 The position indicated by "P" in the middle.

[0031] It should be noted that t0 is the residual thickness of the housing 10 after removing the clearance groove 13. Since the bottom of the clearance groove 13 along the wall thickness direction of the first side wall 111 is located between the inner and outer walls of the first side wall 111, and the wall thickness of the first side wall 111 is t, then t0 must be less than t. The side of the first side wall 111 facing the receiving cavity 14 forms a support platform for the pole assembly 20. When the pole assembly 20 abuts against the inner wall of the first side wall 111 (i.e., the first inner wall 1111), the side of the pole assembly 20 can be located in the clearance groove 13, avoiding... The side interferes with the transition fillet 12. Meanwhile, since t0≤t2, the lowest point of the clearance groove 13 along the wall thickness direction of the second side wall 112 is located between the inner and outer walls of the second side wall 112, or flush with the inner wall of the second side wall 112, to avoid affecting the setting of the pole group. If t0 is greater than t2, the shell 10 is more difficult to form, and the setting of the clearance groove 13 loses its meaning of avoiding the pole group 20, and cannot form an effective clearance space. The pole group 20 will still interfere with the position of the transition fillet 12. If t0 is less than 0.3 mm, the structural strength of the shell 10 at the transition fillet 12 will be significantly reduced, making it difficult to withstand various stresses in subsequent use. This can easily lead to deformation or even cracking of the shell 10, affecting the normal use and safety of the battery cell.

[0032] In the battery cell of this embodiment, by providing a clearance groove 13 at the connection point of two adjacent sidewalls 11 on the housing 10, and with the clearance groove 13 located inside the housing 10, a clearance space is formed at the transition fillet 12 at the connection point of the two adjacent sidewalls 11 to avoid the edge of the electrode group 20. This allows the electrode group 20 to avoid interference with the transition fillet 12 during assembly without adding a side plate 40 or reducing the size of the electrode group itself. This ensures no interference between the electrode group 20 and the housing 10, while improving the utilization rate of the internal space of the battery cell and improving the energy density of the battery cell. At the same time, by limiting the wall thickness t0 of the portion of the housing 10 corresponding to the clearance groove 13 to be no greater than the wall thickness t2 of the second sidewall 112 and no less than 0.3 mm, it can be ensured that the clearance groove 13 can provide effective clearance for the electrode group 20, avoiding interference between the electrode group 20 and the housing 10, and ensuring that the housing 10 can be smoothly processed and formed. It can also ensure that the housing 10 still has sufficient structural strength after the clearance groove 13 is provided, thereby ensuring the safety of the battery cell.

[0033] It should be noted that the shell 10 has X, Y, and Z directions that intersect each other in pairs; preferably, the X, Y, and Z directions intersect perpendicularly in pairs. Specifically, the X, Y, and Z directions are as follows: Figure 4 As shown by the middle arrow, a rectangular coordinate system is formed.

[0034] Preferably, such as Figures 4 to 5 As shown, Figure 5 for Figure 4 The cross-sectional view of the casing along the XY plane shown indicates that there are four sidewalls 11. Each sidewall 11 includes two large casing surfaces arranged opposite each other along the thickness direction (Y direction) of the battery cell, and two narrow casing surfaces arranged opposite each other along the width direction (X direction) of the battery cell. The dimensions of the large casing surfaces and the narrow casing surfaces along the length direction (Z direction) of the battery cell are equal. The dimension of the large casing surface along the X direction is greater than the dimension of the narrow casing surface along the Y direction, that is, the area of ​​the large casing surface is greater than the area of ​​the narrow casing surface. One of the first sidewall 111 and the second sidewall 112 is a large casing surface and the other is a narrow casing surface. Optionally, the first sidewall 111 is a large casing surface and the second sidewall 112 is a narrow casing surface, or the first sidewall 111 is a narrow casing surface and the second sidewall 112 is a large casing surface.

[0035] It should be noted that the cross-section of the shell 10 in the XY plane is quadrilateral. Figure 6 , Figure 7 All of these are enlarged schematic diagrams of one of the four corners of the quadrilateral on the cross section of the shell 10 along the XY plane.

[0036] In one embodiment, the wall thickness t2 of the second sidewall 112 ranges from 0.5 mm to 1.5 mm. Further combining... Figures 5 to 7As shown, in a cross-section perpendicular to the Z direction, the first sidewall 111 extends along a first direction, and the second sidewall 112 extends along a second direction. The wall thickness of the second sidewall 112 refers to the thickness of the second sidewall 112 along the first direction, where the first direction refers to... Figure 6 and Figure 7 The first direction indicated by the middle arrow, the second direction refers to... Figure 6 and Figure 7 The "second direction" indicated by the middle arrow is perpendicular to the first direction. When the second sidewall 112 is a narrow surface of the shell, the first direction is parallel to the X direction and the second direction is parallel to the Y direction. When the second sidewall 112 is a large surface of the shell, the first direction is parallel to the Y direction and the second direction is parallel to the X direction.

[0037] It should be noted that if t2 is less than 0.5 mm, the second sidewall 112 is too thin, resulting in insufficient structural strength. During the assembly of the electrode assembly 20 or subsequent use of the battery cell, the second sidewall 112 may deform or even crack due to insufficient pressure or stress, thus affecting the normal use and safety of the battery cell. If t2 is greater than 1.5 mm, although the structural strength of the second sidewall 112 is guaranteed, it increases the overall weight and cost of the battery cell and is also detrimental to improving the energy density of the battery cell. Therefore, by limiting the wall thickness of the second sidewall 112 to the range of 0.5 mm to 1.5 mm, it is possible to ensure that the second sidewall 112 has sufficient structural strength, thereby ensuring the safety of the battery cell, while also avoiding excessive weight of the casing 10, which is beneficial for reducing costs and improving the energy density of the battery cell.

[0038] Optionally, the value of t2 is any one of 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, or a value between any two of these values.

[0039] In one embodiment, the wall of the clearance groove 13 includes a first arcuate surface 131 and a connecting surface 132. The first arcuate surface 131 is connected to the inner wall of the second side wall 112, and the connecting surface 132 is connected between the first arcuate surface 131 and the inner wall of the first side wall 111. The connecting surface 132 has a first side connected to the inner wall of the first side wall 111 and a second side connected to the first arcuate surface 131. Along a direction perpendicular to the inner wall of the second side wall 112, the distance from the first side to the inner wall of the second side wall 112 is L1, and the distance from the second side to the inner wall of the second side wall 112 is L2, wherein L1≥L2. By setting the groove wall of the clearance groove 13 to include at least a first arc-shaped surface 131 and a connecting surface 132, the first arc-shaped surface 131 is adapted to the transition fillet 12, and the distance from the connection position of the connecting surface 132 and the inner wall of the first side wall 111 to the second side wall 112 is greater than the distance from the connection position of the connecting surface 132 and the first arc-shaped surface 131 to the second side wall 112, the opening of the clearance groove 13 gradually expands towards the receiving cavity 14, which facilitates the processing and shaping of the clearance groove 13, and can increase the size of the clearance groove 13, maximize the clearance space, and reduce the risk of interference between the pole group 20 and the transition fillet 12.

[0040] Preferably, the first arcuate surface 131 is smoothly connected to the inner wall of the second sidewall 112; alternatively, the connecting surface 132 is directly or indirectly connected to the inner wall of the first sidewall 111; the connecting surface 132 is directly or indirectly connected to the first arcuate surface 131.

[0041] In one embodiment, the connecting surface 132 is set at an angle to the inner wall of the first sidewall 111, and the angle between the extended surface of the connecting surface 132 and the inner wall of the first sidewall 111 is θ. It should be noted that the connecting surface 132 is planar or inclined, with a simple structure and easy processing and forming. The extended surface of the connecting surface 132 refers to the portion of the plane containing the connecting surface 132 extending into the receiving cavity 14 of the housing.

[0042] In one embodiment, the first sidewall 111 is the large surface of the shell, where 10°≤θ≤90°. It should be noted that the large surface of the shell is the sidewall 11 with a larger area on the shell 10. After the clearance groove 13 is provided, the side of the large surface of the shell facing the receiving cavity 14 forms a support platform for the support pole assembly 20. The smaller the angle θ between the extended surface of the connecting surface 132 and the inner wall of the first sidewall 111, the gentler the slope of the connecting surface 132. The closer the intersection of the connecting surface 132 and the inner wall of the first sidewall 111 is to the center of the first sidewall 111, the smaller the support surface of the support platform for supporting the pole assembly 20. If θ is less than 10°, the included angle is too small, resulting in an insufficient inner wall area of ​​the first sidewall 111, which affects the support effect of the first sidewall 111 on the electrode group 20. The stability of the electrode group 20 is poor, and the vibration and shock resistance of the battery cell is poor. If θ is greater than 90°, the connecting surface 132 is inclined away from the center of the first sidewall 111, which causes the opening of the relief groove 13 to gradually shrink towards the receiving cavity 14. The relief groove 13 cannot provide effective relief space for the edge of the electrode group 20, and the processing is more difficult, resulting in a lower shell forming yield, and it may even be impossible to form successfully.

[0043] Therefore, when the first sidewall 111 is the large surface of the shell, by limiting the angle between the extended surface of the connecting surface 132 and the inner wall of the first sidewall 111 to be within the range of 10° to 90°, it can ensure that the clearance groove 13 can be formed smoothly, improve the shell forming yield, and ensure that the first sidewall 111 has sufficient support area for the electrode group 20, improve the stability of the electrode group 20, and thus improve the vibration and shock resistance of the battery cell.

[0044] Optionally, the value of θ is any one of 10°, 20°, 30°, 45°, 50°, 60°, 70°, 80°, 85°, 90° or a value between any two of them.

[0045] In other embodiments, the first sidewall 111 is a narrow face of the housing, where 25°≤θ≤90°. It should be noted that the narrow face of the housing is the sidewall 11 with a smaller area on the housing 10. With the narrow face and the clearance groove 13, the side of the narrow face facing the receiving cavity 14 forms a support platform for the electrode assembly 20. To ensure that the narrow face of the housing can provide sufficient support area for the electrode assembly 20, the minimum angle between the extended surface of the connecting surface 132 and the inner wall of the narrow face of the housing should be greater than the angle between the extended surface of the connecting surface 132 and the inner wall of the large surface of the housing. If θ is less than 25°, the inner wall area of ​​the narrow face of the housing will be too small, affecting the support effect of the narrow face of the housing on the electrode assembly 20, resulting in poor stability of the electrode assembly 20 and poor vibration and shock resistance of the battery cell. Therefore, when the first sidewall 111 is a narrow surface of the shell, by limiting the angle between the extended surface of the connecting surface 132 and the inner wall of the narrow surface of the shell to be within the range of 25° to 90°, it can ensure that the clearance groove 13 can be formed smoothly, improve the shell forming yield, and ensure that the first sidewall 111 has sufficient support area for the electrode group 20, improve the stability of the electrode group 20, and thus improve the vibration and shock resistance of the battery cell.

[0046] Optionally, the value of θ is any one of 25°, 30°, 40°, 45°, 50°, 60°, 70°, 80°, 85°, 90° or a value between any two of them.

[0047] In other embodiments, the connecting surface 132 may also be an arc-shaped surface, so that the surface of the relief groove 13 transitions smoothly, avoiding stress concentration that could cause the casing to deform or crack, thereby further improving the safety and reliability of the battery cell.

[0048] It should be noted that the second sidewall 112 and the first sidewall 111 are connected by a transition fillet 12. The clearance groove 13 can be provided only on the transition fillet 12, that is, the clearance groove 13 is formed by the inner wall of the transition fillet 12; or the clearance groove 13 can be provided to extend beyond the transition fillet 12, that is, the clearance groove 13 is formed by the transition fillet 12 and a portion of the first sidewall 111 near the transition fillet 12.

[0049] In one embodiment, the wall of the clearance groove 13 further includes a planar region 133, which connects the first arcuate surface 131 and the connecting surface 132, and is parallel to the inner wall of the first side wall 111. It should be noted that the planar region 133 is tangentially disposed to the first arcuate surface 131, and the position where the planar region 133 connects to the first arcuate surface 131 is the bottommost point of the clearance groove 13 along the wall thickness direction of the first side wall 111. The plane containing the planar region 133 is located between the inner and outer walls of the first side wall 111. By adding a planar region 133 between the first arcuate surface 131 and the connecting surface 132, the area occupied by the clearance groove 13 on the first side wall 111 is increased, further ensuring that the clearance groove 13 can provide effective clearance space for the electrode assembly 20, and facilitating the processing and forming of the clearance groove 13. It also reduces stress concentration during the shell forming process, avoiding the risk of deformation or breakage caused by excessive local stress, thereby improving the safety of the battery cell.

[0050] In one embodiment, along the wall thickness direction of the first sidewall 111, the thickness of the first sidewall 111 is t, and the distance between the planar region 133 and the outer wall of the first sidewall 111 is t1, where 0.3 ≤ t1 / t ≤ 0.95. Further combining... Figure 7 As shown, the wall thickness direction of the first sidewall 111 refers to... Figure 7 The "second direction" indicated by the middle arrow means that the wall thickness direction of the first sidewall 111 is perpendicular to the wall thickness direction of the second sidewall 112. The distance between the planar region 133 and the outer wall of the first sidewall 111 is the position where the thickness of the first sidewall 111 is the smallest. If t1 / t is less than 0.3, the distance between the planar region 133 and the outer wall of the first sidewall 111 is too small, the pressure resistance of the shell 10 is insufficient, it is easy to tear, and it affects the electrical safety. If t1 / t is greater than 0.95, the distance between the planar region 133 and the outer wall of the first sidewall 111 is too small, so the depth of the clearance groove 13 on the first sidewall 111 is too small, which cannot provide enough clearance space for the electrode group 20. It may still cause interference between the electrode group 20 and the transition fillet 12 of the shell, affecting the normal assembly and use of the battery cell. Therefore, by limiting t1 / t to a value within the range of 0.3 to 0.95, it is possible to ensure that the first sidewall 111 has sufficient structural strength to prevent the casing from tearing and ensure the safety of the battery cell, while also allowing the clearance groove 13 to provide sufficient clearance space for the pole group 20, avoiding interference between the pole group 20 and the transition fillet 12 of the casing 10, and ensuring normal assembly and use of the battery cell.

[0051] Optionally, the value of t1 / t is any one of 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95 or a value between any two values.

[0052] In one embodiment, the value of t1 is in the range of t1 ≥ 0.3 mm. If t1 is less than 0.3 mm, the distance between the planar region 133 and the outer wall of the first sidewall 111 is too small, resulting in insufficient structural strength and pressure resistance of the casing 10 at that location, making it prone to tearing and affecting electrical safety. Therefore, by limiting t1 to be greater than or equal to 0.3 mm, it is possible to ensure that the casing 10 has sufficient structural strength, prevent casing tearing, and ensure the safety of the battery cell.

[0053] In one embodiment, the value of t ranges from 0.8 mm to 2 mm. t represents the thickness of the first sidewall 111. If t is less than 0.8 mm, the thickness of the first sidewall 111 is too small, resulting in poor structural strength and insufficient overall strength of the casing 10. This makes the casing prone to deformation or even breakage during cell manufacturing or use, severely impacting the cell's safety and lifespan. If t is greater than 2 mm, while it enhances the strength of the casing 10, it also increases the weight of the casing 10, thereby increasing the overall weight and volume of the cell, which is detrimental to improving the cell's energy density and miniaturization. Therefore, by limiting t to a value between 0.8 mm and 2 mm, it is possible to ensure that the casing 10 has sufficient strength to protect the internal structure of the cell while controlling the overall weight and volume of the cell, which is beneficial for improving the cell's energy density and achieving miniaturization.

[0054] Optionally, the value of t is any one of 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, or a value between any two of these values.

[0055] In one embodiment, the dimension of the planar region 133 along the direction perpendicular to the inner wall of the second sidewall 112 is L, where 0 ≤ L ≤ 10 mm. It should be noted that a clearance groove 13 is integrally provided at the intersection of two adjacent sidewalls 11. The clearance groove 13 extends along the Z direction, and the direction perpendicular to the inner wall of the second sidewall 112 is the first direction. L is the dimension of the planar region 133 along the first direction, i.e., L is the width of the planar region 133. Specifically, when the first sidewall 111 is the large surface of the shell, L is the dimension of the planar region 133 along the X direction; when the first sidewall 111 is the narrow surface of the shell, L is the dimension of the planar region 133 along the Y direction. When L equals 0, it indicates that no planar region 133 is provided (e.g., ...). Figure 6(As shown); if L is greater than 10 mm, the size of the planar region 133 is too large, and the clearance groove 13 occupies too much space on the first sidewall 111 along the first direction, resulting in too small an inner wall area on the first sidewall 111 for supporting the electrode group 20, affecting the support effect of the first sidewall 111 on the electrode group 20, and causing poor stability of the electrode group 20. Therefore, by limiting the width of the planar region 133 to between 0 and 10 mm, it is possible to avoid the clearance groove 13 occupying too much space on the first sidewall 111, thereby ensuring that the first sidewall 111 has sufficient support area for the electrode group 20, improving the stability of the electrode group 20, and thus improving the overall performance of the cell.

[0056] Optionally, the value of L is any one of 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, or a value between any two of these values.

[0057] In one embodiment, the connecting surface 132 and the planar region 133 are connected by a second arcuate surface 134 (e.g., Figure 7 (As shown). By providing a second arc-shaped surface 134 between the planar area 133 and the connecting surface 132, a smooth transition is achieved between the connecting surface 132 and the planar area 133, avoiding sharp corners. This effectively alleviates the stress concentration phenomenon at the junction of the connecting surface 132 and the planar area 133, thereby significantly enhancing the fatigue resistance of the shell 10, preventing deformation or even cracking of the shell 10 during manufacturing or use, and improving the safety of the shell 10.

[0058] In other embodiments, the clearance groove 13 does not have a flat area 133, and the connecting surface 132 and the first arc-shaped surface 131 are connected by a fourth arc-shaped surface 136 (e.g., Figure 6 As shown in the figure, similarly, the fourth arc surface 136 enables a smooth transition between the connecting surface 132 and the first arc surface 131, avoiding sharp corners and effectively alleviating the stress concentration phenomenon at the junction of the connecting surface 132 and the second arc surface 134. This significantly enhances the fatigue resistance of the shell 10, prevents the shell 10 from deforming or even breaking during manufacturing or use, and improves the safety of the shell 10.

[0059] In one embodiment, the radius of the first arc-shaped surface 131 is R, where 0.5 mm ≤ R ≤ 4 mm. If R is less than 0.5 mm, the radius of the first arc-shaped surface 131 is too small, making the clearance groove 13 difficult to process, and the opening size of the clearance groove 13 is too small, which cannot provide sufficient clearance space for the edge of the pole group 20, and there is still a risk of the pole group being damaged due to interference with the transition fillet 12; if R is greater than 4 mm, the radius of the first arc-shaped surface 131 is too large, causing the clearance groove 13 to occupy too much space in the first sidewall 111, which reduces the inner wall area of ​​the first sidewall 111 used to support the pole group 20, affecting the support effect of the first sidewall 111 on the pole group 20, and the stability of the pole group 20 deteriorates. Therefore, by limiting R to a value within the range of 0.5 mm to 4 mm, it is possible to ensure that the clearance groove 13 has a suitable opening size, providing sufficient clearance space for the edge of the pole group 20 and avoiding interference damage between the pole group 20 and the transition fillet 12, while also preventing the clearance groove 13 from occupying too much space, ensuring that the first sidewall 111 has sufficient support area for the pole group 20, improving the stability of the pole group 20, and thus improving the overall performance of the cell.

[0060] Optionally, the value of R is any one of 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, or a value between any two of these values.

[0061] In one embodiment, the connecting surface 132 and the inner wall of the first sidewall 111 are connected by a third arc-shaped surface 135. By providing a third arc-shaped surface 135 between the connecting surface 132 and the inner wall of the first sidewall 111 for a smooth transition, sharp corners are avoided at the connection between the connecting surface 132 and the inner wall of the first sidewall 111, preventing sharp corners from cutting the electrode assembly 20, thereby improving the safety performance of the battery cell.

[0062] According to an embodiment of the present invention, another aspect provides a battery cell, comprising: the aforementioned housing 10 and an electrode assembly 20, wherein the electrode assembly is disposed in a receiving cavity 14 of the housing 10. Optionally, the battery cell is a lithium-ion battery cell.

[0063] In one embodiment, the housing 10 has an open end at at least one end along the Z direction, and the battery cell further includes a cover plate assembly 30, which covers the open end of the housing 10 to close the housing 10. The cover plate assembly includes a cover plate body, which is welded to the side wall 11 of the housing 10. The cover plate body has a terminal hole, through which a terminal is inserted. The terminal is electrically connected to the tab on the electrode group 20. An insulating sealing structure is provided between the terminal and the cover plate body to ensure the insulation between the terminal and the cover plate body.

[0064] Hereinafter, the effects of different values of the wall thickness t0 between the side of the transition fillet 12 on the casing 10 facing away from the accommodating cavity 14 and the groove wall of the escape groove 13 and the wall thickness t2 of the second side wall 112 on the performance of the battery cell are verified in different cases. Specifically, whether the casings of the battery cells in different examples and comparative examples can be successfully molded is recorded, and a pressure resistance test is performed on the battery cells assembled with the molded casings. The test process is as follows: after clamping the casing, the interior of the casing is inflated until the pressure reaches 1.2 MPa, the pressure is maintained for at least 30 s, and then air tightness detection is performed (requirement for leak rate standard: ≤10^-7 Pa·m 3 / s), a battery cell with a leak rate less than or equal to 10^-7Pa·m 3 / s is qualified (OK), and a battery cell with a leak rate greater than 10^-7 Pa·m 3 / s is unqualified (NG). 10 battery cells are used for testing in each group of examples and comparative examples, and the number of qualified battery cells in the pressure resistance test is recorded.

[0065] 1) When the first side wall 111 is a large surface of the casing, t2 is the wall thickness of the narrow surface of the casing, and the test results of the examples and comparative examples are shown in Table 1.

[0066] Table 1

[0067] It can be seen from Table 1 that for the battery cells of Examples 1-1 to 1-14, the values of t0 are all within the range of 0.3 mm≤t0≤t2 defined in the present application, and the values of t2 are all within the range of 0.5 mm to 1.5 mm defined in the present application. The molding yield of the casing in each example is ≥99%, and the pressure resistance tests of 10 battery cells in each example are all qualified (OK), that is, the molding yield of the casing is high, indicating that the performance of the battery cell is good; while for the battery cell of Comparative Example 1-1, the value of t0 is 0.2 mm, which is less than 0.3 mm and is not within the range defined in the present application, and only 5 of the 10 tested battery cells pass the pressure resistance test, so the pressure resistance test of this group of comparative battery cells is NG.

[0068] In conclusion, for the case where the first side wall 111 is a large surface of the casing, when the wall thickness t0 between the side of the transition fillet 12 facing away from the accommodating cavity 14 and the groove wall of the escape groove 13 and the wall thickness t2 of the narrow surface of the casing satisfy the relational expression 0.3 mm≤t0≤t2, and t2 is within the range of 0.5 mm to 1.5 mm, it can ensure that the casing is molded smoothly, has high structural strength, and ensures the safety of the battery cell.

[0069] 2) When the first side wall 111 is a narrow surface of the casing, t2 is the wall thickness of the large surface of the casing, and the test results of the examples and comparative examples are shown in Table 2.

[0070] Table 2

[0071] As can be seen from Table 2, for the cells of Examples 2-1 to 2-14, the value of t0 is within the range of 0.3 mm ≤ t0 ≤ t2 as defined in this application, and the value of t2 is within the range of 0.5 mm to 1.5 mm as defined in this application. The shell molding yield of each set of examples is ≥99%, and the withstand voltage test of 10 cells in each set of examples is qualified (OK), that is, the shell molding yield is high, indicating that the performance of the cells is good. However, for the cell of Comparative Example 2-1, the value of t0 is 0.2 mm, which is less than 0.3 mm and is not within the range defined in this application. Only 5 of the 10 cells tested are qualified for withstand voltage test, so the withstand voltage test of this set of comparative example cells is NG.

[0072] In summary, for the case where the first sidewall 111 is a narrow surface of the shell, when the wall thickness t0 between the side of the transition fillet 12 away from the receiving cavity 14 and the groove wall of the clearance groove 13, and the wall thickness t2 of the large surface of the shell satisfy the relationship 0.3 mm≤t0≤t2, and when t2 is taken in the range of 0.5 mm to 1.5 mm, the shell can be formed smoothly and has high structural strength, thus ensuring the safety of the battery cell.

[0073] The following examples and comparative examples verify the impact of different values ​​of θ on the performance of the battery cell. Specifically, the success of the casing formation for the battery cells in different examples and comparative examples is recorded, and vibration and shock tests are conducted on the battery cells assembled from the formed casings.

[0074] 1) When the first sidewall 111 is the large surface of the shell, the test results of the embodiment and the comparative example are shown in Table 3.

[0075] Table 3

[0076] As shown in Table 3, for the cells of Examples 3-1 to 3-9, the value of θ is within the range of 10° to 90° as defined in this application. The test results show that the shell molding yield is ≥99%, and the cell vibration and shock test is passed, indicating that the shell molding yield is high, the impact resistance is good, and the requirements are met. However, for the cell of Comparative Example 3-1, the value of θ is 5°, which is less than 10° and is not within the range defined in this application. The area of ​​the first sidewall supporting the electrode group is small, meaning that the area of ​​the inner wall of the large surface of the shell is small, which cannot provide stable support for the electrode group. It is not recommended for use. For the cell of Comparative Example 3-2, the value of θ is 100°, which is greater than 90° and is not within the range defined in this application. The shell cannot be molded and it is not recommended for use.

[0077] In summary, when the first side wall 111 is the large surface of the casing, if the angle between the extended plane of the connecting surface 132 and the inner wall of the large surface of the casing is in the range of 10° to 90°, on the basis that the relief groove 13 can ensure the smooth forming of the casing 10, it can further ensure that the large surface of the casing has a sufficient supporting area for the electrode assembly 20, improve the stability of the electrode assembly 20, and guarantee the vibration and impact resistance of the battery cell.

[0078] 2) When the first side wall 111 is a narrow surface of the casing, the test results of the examples and comparative examples are shown in Table 4.

[0079] Table 4

[0080] It can be seen from Table 4 that, for the battery cells of Examples 4-1 to 4-9, the values of θ are all within the range of 25° to 90° defined in the present application. The test results show that the molding yield of the casing is ≥99%, and the vibration and impact test of the battery cell is passed, that is, the molding yield of the casing is high, the impact resistance is good, which meets the requirements; while for the battery cell of Comparative Example 4-1, the value of θ is 5°, which is less than 10° and not within the range defined in the present application, the area of the electrode assembly supporting surface of the first side wall is small, that is, the area of the inner wall of the narrow surface of the casing is small, which cannot stably support the electrode assembly, so it is not recommended; for the battery cell of Comparative Example 4-2, the value of θ is 100°, which is larger than 90° and not within the range defined in the present application, the casing cannot be molded, so it is not recommended.

[0081] In summary, when the first side wall 111 is a narrow surface of the casing, if the angle between the extended plane of the connecting surface 132 and the inner wall of the narrow surface of the casing is in the range of 25° to 90°, on the basis that the relief groove 13 can ensure the smooth forming of the casing 10, it can further ensure that the narrow surface of the casing has a sufficient supporting area for the electrode assembly 20, improve the stability of the electrode assembly 20, and guarantee the vibration and impact resistance of the battery cell.

[0082] In the following, the influence of different values of t1 / t on the performance of the battery cell is verified by examples and comparative examples in different cases. Specifically, pressure resistance tests are performed on the battery cells of different examples and comparative examples, and the test process is as follows: after clamping the casing, inflate the interior of the casing until the pressure reaches 1.2 MPa, hold the pressure for at least 30 s, and then perform air tightness detection (required leak rate standard: ≤10^-7 Pa·m3 / s). A battery cell with a leak rate less than or equal to 10^-7 Pa·m3 / s during the air tightness detection is qualified (OK), while a battery cell with a leak rate greater than 10^-7 Pa·m3 / s is unqualified (NG). 10 battery cells are used for testing in each of the examples and comparative examples, and the number of qualified battery cells in the pressure resistance test is recorded.

[0083] 1) When the first sidewall 111 is the large surface of the shell, t is the wall thickness of the large surface of the shell, and t1 is the vertical distance between the planar area 133 and the outer wall of the large surface of the shell. The test results of the embodiment and the comparative example are shown in Table 5.

[0084] Table 5

[0085] As shown in Table 5, for the cells of Examples 5-1 to 5-11, the value of t1 / t is within the range of 0.3 to 0.95 as defined in this application. The withstand voltage test of all 10 cells in each example is qualified (OK), indicating that the cell performance is good. However, for the cell of Comparative Example 5-1, the value of t1 / t is 0.2, which is less than 0.3 and not within the range defined in this application. Only 5 out of the 10 tested cells passed the withstand voltage test, so the withstand voltage test of this comparative example cell is not good. For the cell of Comparative Example 5-2, the value of t1 / t is 1, which is greater than 0.95 and not within the range defined in this application. The clearance groove 13 has no flat area 133 and connecting surface 132, and does not have the function of preventing interference between the electrode group and the transition fillet 12 of the shell, or the effect is weak. It is not recommended to use it.

[0086] In summary, when the first sidewall 111 is the large surface of the casing, when t1 / t is taken within the range of 0.3 to 0.95 as defined in this application, it can ensure that the large surface of the casing has sufficient pressure resistance to prevent the casing from tearing and ensure the safety of the battery cell. At the same time, it can also provide sufficient clearance space for the electrode group 20 in the clearance groove 13, avoid interference between the electrode group 20 and the transition fillet 12 of the casing 10, and ensure the normal assembly and use of the battery cell.

[0087] 2) When the first sidewall 111 is the narrow surface of the shell, t is the wall thickness of the large surface of the shell, and t1 is the vertical distance between the planar area 133 and the outer wall of the narrow surface of the shell. The test results of the embodiment and the comparative example are shown in Table 6.

[0088] Table 6

[0089] As shown in Table 6, for the cells of Examples 6-1 to 6-11, the value of t1 / t is within the range of 0.3 to 0.95 as defined in this application. The withstand voltage test of all 10 cells in each example is qualified (OK), indicating that the cell performance is good. However, for the cell of Comparative Example 6-1, the value of t1 / t is 0.2, which is less than 0.3 and not within the range defined in this application. Only 5 of the 10 cells tested are qualified for withstand voltage test, so the withstand voltage test of this comparative example cell is not good. For the cell of Comparative Example 6-2, the value of t1 / t is 1, which is greater than 0.95 and not within the range defined in this application. The clearance groove 13 has no flat area 133 and connecting surface 132, and does not have the function of preventing interference between the transition fillet 12 of the electrode group and the shell, or the effect is weak. It is not recommended to use it.

[0090] In summary, when the first sidewall 111 is a narrow surface of the casing, when t1 / t is taken within the range of 0.3 to 0.95 as defined in this application, it can ensure that the narrow surface of the casing has sufficient pressure resistance to prevent the casing from tearing and ensure the safety of the battery cell. At the same time, it can also provide sufficient clearance space for the electrode group 20 in the clearance groove 13, avoid interference between the electrode group 20 and the transition fillet 12 of the casing 10, and ensure the normal assembly and use of the battery cell.

[0091] Unless otherwise stated, the values ​​and test methods of the parameters mentioned in this application can be determined using commonly used test methods in the art, such as using an electric vibration table to perform vibration tests on the battery cell. Unless otherwise stated, the test temperature for each parameter is 25°C.

[0092] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A housing, characterized in that, include: Multiple sidewalls are connected end to end to form a receiving cavity. A transition fillet is formed at the connection between two adjacent sidewalls, and a relief groove is provided at the transition fillet. The relief groove is formed by the recess of the surface of the transition fillet facing the receiving cavity. Along the radial direction of the transition fillet, the wall thickness between the side of the transition fillet away from the receiving cavity and the groove wall of the relief groove is t0. Wherein, one of the two adjacent sidewalls is a first sidewall and the other is a second sidewall, and along the wall thickness direction of the first sidewall, the bottom of the clearance groove is located between the inner wall and the outer wall of the first sidewall; The thickness of the second sidewall is t2, and the range of t0 is: 0.3 mm ≤ t0 ≤ t2.

2. The housing according to claim 1, characterized in that, The wall thickness t2 of the second sidewall has a range of 0.5 mm ≤ t2 ≤ 1.5 mm.

3. The housing according to claim 1, characterized in that, The clearance groove wall includes a first arc-shaped surface and a connecting surface. The first arc-shaped surface is connected to the inner wall of the second side wall. The connecting surface is connected between the first arc-shaped surface and the inner wall of the first side wall. The connecting surface has a first side connected to the inner wall of the first side wall and a second side connected to the first arc-shaped surface. Along a direction perpendicular to the inner wall of the second side wall, the distance from the first side to the inner wall of the second side wall is L1, and the distance from the second side to the inner wall of the second side wall is L2, where L1 ≥ L2.

4. The housing according to claim 3, characterized in that, The connecting surface is set at an angle to the inner wall of the first sidewall, and the angle between the extended surface of the connecting surface and the inner wall of the first sidewall is θ. The first sidewall is a large surface of the shell, wherein 10°≤θ≤90°; or, the first sidewall is a narrow surface of the shell, wherein 25°≤θ≤90°.

5. The housing according to claim 3, characterized in that, The wall of the clearance groove also includes a planar area, which is connected between the first arc-shaped surface and the connecting surface, and the planar area is parallel to the inner wall of the first side wall.

6. The housing according to claim 5, characterized in that, Along the wall thickness direction of the first sidewall, the thickness of the first sidewall is t, and the distance between the planar region and the outer wall of the first sidewall is t1, where 0.3≤t1 / t≤0.

95.

7. The housing according to claim 6, characterized in that, The range of values ​​for t1 is: t1 ≥ 0.3 mm; And / or, the range of t is: 0.8 mm ≤ t ≤ 2 mm.

8. The housing according to claim 5, characterized in that, The intersection line of the extended surface of the inner wall of the first sidewall and the extended surface of the inner wall of the second sidewall extends along the Z direction, the clearance groove extends along the Z direction, and the size of the planar area is L in the direction perpendicular to the Z direction within the planar area, where 0≤L≤10 mm. And / or, the connecting surface and the planar area are connected by a second arc-shaped surface.

9. The housing according to any one of claims 5 to 8, characterized in that, The radius of the first arc-shaped surface is R, where 0.5 mm ≤ R ≤ 4 mm; And / or, the connecting surface is connected to the inner wall of the first sidewall via a third arc-shaped surface.

10. A battery cell, characterized in that, include: The housing according to any one of claims 1 to 9; The pole assembly is disposed in the receiving cavity of the housing.

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