Battery cell shell and battery cell

Abstract

The utility model discloses a battery cell shell and a battery cell, an accommodating space is limited in the battery cell shell, the accommodating space can be used for mounting a roll core with arc-shaped corner parts at two ends, at least one group of groove pair is formed in the inner wall of the battery cell shell, the groove pair comprises two grooves which are spaced and oppositely arranged, and the two grooves are arranged in the accommodating space. And the inner wall surface of each groove is an arc-shaped surface so as to support the corner part of the roll core. The battery cell shell disclosed by the utility model can improve the supporting property of the roll cell, is convenient to implement, and can ensure the utilization rate of the accommodating space and the capacity of the battery cell.

Description

Technical Field

[0001] The present application relates to the field of battery cell technology, and more specifically, to a battery cell shell and a battery cell. Background Art

[0002] The square wound sodium battery cell has a corner R part after hot pressing, which results in the R part having no support during the subsequent charging and discharging process. There is residual stress with nowhere to release, which accumulates over a long period of time and causes sodium precipitation, leading to cycle attenuation and increased safety risks. The existing aluminum shells on both sides cannot provide effective support for the R part due to the corner gap left at the R part position.

[0003] The existing technology mostly uses a support member that is separate from the shell and inserted between the winding core and the inner wall of the shell. However, the separate support member requires additional mold development during the research and development process, and during the production process, the support member needs to be installed in the shell and fixed before the bare battery cell is put into the shell. The process is complicated, and an extra step is added. In addition, an extra separate material in the production process will increase the complexity. Therefore, the battery shell of the existing technology is relatively complicated in many links such as research and development, management, and production. Utility Model Content

[0004] One object of the present application is to provide a battery cell casing that can at least solve the technical problems of the prior art of using separate support members to support the winding core, which leads to complex manufacturing and high costs.

[0005] Another object of the present application is to provide a battery cell, comprising the above-mentioned battery cell shell.

[0006] In order to achieve the above objectives, this application provides the following technical solutions.

[0007] According to the battery cell shell of the first aspect embodiment of the present application, a receiving space is defined within the battery cell shell, and the receiving space can be used to install a winding core with arc-shaped corner portions at both ends. The inner wall of the battery cell shell has at least one set of groove pairs, and the groove pairs include two spaced-apart and oppositely arranged grooves, and the inner wall surface of each groove is an arc-shaped surface to support the corner portion.

[0008] Optionally, the battery cell housing includes: a first side plate and a second side plate, which are oppositely arranged in a first direction; a third side plate and a fourth side plate, which are oppositely arranged in a second direction, and the third side plate and the fourth side plate are respectively connected to the first side plate and the second side plate, and any one of the third side plate and the fourth side plate has the groove opening towards the other; a bottom plate, the bottom plate, the first side plate, the second side plate, the third side plate and the fourth side plate enclose the accommodation space, and the first side plate, the second side plate, the third side plate and the fourth side plate enclose an open end communicating with the accommodation space; a cover plate, the cover plate is installed at the open end, the cover plate and the bottom plate are oppositely arranged in a third direction and are used to close the accommodation space, and the groove extends in the direction from the bottom plate to the cover plate.

[0009] Optionally, in the direction from the bottom plate to the cover plate, the third side plate and / or the fourth side plate includes: a first surface having the groove; a second surface connected to the outer edge of the open end; a third surface respectively connected to the first surface and the second surface, the first surface is located on one side of the second surface close to the center line of the accommodation space, and the third surface and the first surface and the second surface cooperate to form a stepped portion, and the third surface is a stepped surface.

[0010] Optionally, in the direction from the bottom plate to the cover plate, the length of the groove is A h , the length of the third side plate or the fourth side plate provided with the groove is W h , 0.5 ≤ A h / W h ≤ 0.98.

[0011] Optionally, A h / W h is 0.95.

[0012] Optionally, the thickness of the bottom plate is T1, in the second direction, the distance between the first surface and the second surface is T2, the thickness of the third side plate or the fourth side plate provided with the second surface on the battery cell housing is T3, the cover plate is provided with an explosion-proof valve, the maximum pressure that the explosion-proof valve can withstand is P1, the maximum pressure that the connection position between the outer periphery of the cover plate and the open end can withstand is P2, and the maximum pressure that the third side plate or the fourth side plate provided with the second surface can withstand is P3, where, T2 ≤ T3 < T1, T2 is [0.4T1, 0.75T1], and P1 < P2 ≤ P3.

[0013] Optionally, the third side plate and / or the fourth side plate is a hollow structure.

[0014] Optionally, the first side panel, the second side panel, the third side panel, the fourth side panel and the bottom panel are connected as an integral piece.

[0015] Optionally, the inner wall surface of the battery cell shell has a plurality of protrusions, and two adjacent protrusions are spaced apart and distributed. Each protrusion is provided with a groove segment, and a plurality of the groove segments form one groove.

[0016] According to the second aspect of the present application, the battery cell includes: a battery cell shell, which is any of the battery cell shells described above; a winding core, which is installed in the battery cell shell, and the winding core and the battery cell shell are insulated and connected.

[0017] According to the embodiment of the present application, the inner wall of the battery cell shell is provided with at least one pair of grooves, and the groove pair includes two spaced-apart grooves, which can not only support the corners of the core when the core expands, thereby alleviating the problem of lithium deposition at the corners; but also ensure the volume of the core, increase the capacity of the battery cell, simplify the assembly process, and improve assembly efficiency.

[0018] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0020] Figure 1 is a schematic diagram of the three-dimensional structure of a battery cell according to an embodiment of the present application;

[0021] Figure 2 is a partial exploded view of a battery cell according to one embodiment of the present application;

[0022] Figure 3 is a schematic diagram of a partial structure of a battery cell casing according to an embodiment of the present application;

[0023] Figure 4 is a schematic diagram of a partial structure of a battery cell casing according to another embodiment of the present application;

[0024] Figure 5 is a schematic diagram of a partial structure of a battery cell casing according to yet another embodiment of the present application;

[0025] Figure 6 is a schematic diagram of a partial structure of a battery cell housing at one angle according to an embodiment of the present application;

[0026] Figure 7is a partial structural schematic diagram of a battery cell housing according to an embodiment of the present application from another angle;

[0027] Figure 8 It is a partially enlarged view of a battery cell casing according to an embodiment of the present application.

[0028] Figure Numbers

[0029] Cell housing 100; receiving space 101; groove 102; groove section 103; open end 104; protrusion 105;

[0030] First side plate 10; second side plate 20; third side plate 30; fourth side plate 40; bottom plate 50; cover plate 60; first surface 71; second surface 72; third surface 73; blue film 80; explosion-proof valve 90;

[0031] Winding core 200; corner portion 201. DETAILED DESCRIPTION

[0032] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0033] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0034] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0035] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0036] It should be noted that similar reference numerals and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further discussed in subsequent figures. The battery cell housing 100 according to an embodiment of the present application is described in detail below with reference to the accompanying figures.

[0037] like Figures 1 to 8As shown, according to an embodiment of the present application, a receiving space 101 is defined within the cell shell 100. The receiving space 101 can be used to install a core 200 with arc-shaped corner portions 201 at both ends. The inner wall of the cell shell 100 is provided with at least one set of groove pairs, and the groove pairs include two grooves 102 spaced apart and arranged oppositely. For example, a core 200 has a corner portion 201 at each of its left and right ends, and each set of groove pairs includes two grooves 102 spaced apart and arranged oppositely. The corner portion 201 at the left end of the core 200 corresponds to one groove 102, and the corner portion 201 at the right end of the core 200 corresponds to the other groove 102. The inner wall surface of each of the grooves 102 is an arc-shaped surface to support the corner portion 201. In other words, each groove 102 corresponds to a corner portion 201 of the core 200, and at least a portion of the inner wall surface of the groove 102 supports the expanded corner portion 201.

[0038] In other words, a receiving space 101 is formed in the cell casing 100 according to an embodiment of the present application, and the receiving space 101 can be used to accommodate the winding core 200. A plurality of grooves 102 are provided on the inner wall of the cell casing 100. The depth of the grooves 102 can extend along the wall thickness direction of the cell casing 100, and the length direction of the grooves 102 can be consistent with the extension direction of the corner portion 201 of the winding core 200. One groove 102 is provided on the inner wall of one side of the cell casing 100, and another groove 102 is provided on the inner wall of the other side. The two grooves 102 spaced apart and arranged oppositely can form a group of groove pairs. For example, two inner walls of the cell casing 100 are spaced apart along a first direction, and two inner walls are spaced apart along a second direction. In the second direction, two grooves 102 spaced apart and arranged oppositely can form a group of groove pairs. For another example, the inner wall of the cell housing 100 includes a left inner wall and a right inner wall, each of which has a groove 102. The opening of the groove 102 on the left inner wall faces the position of the right inner wall, and the opening of the groove 102 on the right inner wall faces the position of the left inner wall. The groove 102 on the left inner wall and the groove 102 on the right inner wall can form a groove pair. Moreover, the number of groove pairs is not limited in this embodiment, that is, the groove pairs can be one or more groups. For example, multiple groups of groove pairs are arranged in sequence along the thickness direction of the cell housing 100. Each group of groove pairs can correspond to one winding core 200, and multiple groups of groove pairs can correspond to multiple winding cores 200.

[0039] Among them, the receiving space 101 can be used to install a core 200 with curved corners 201 at both ends, and the groove 102 corresponds to the corner 201 of the battery cell. During the battery cell cycle, when the corner 201 of the core 200 expands, at least a portion of the inner wall surface of the groove 102 fits with the outer surface of the corner 201, thereby supporting the curved corner 201 and alleviating the problem of lithium deposition at the corner 201. Optionally, when the inner wall surface of the groove 102 completely fits with the outer surface of the corner 201, the curvature of the groove can be the same as the radius of the corner 201 of the core 200, so that the corner 201 of the core 200 installed in the receiving space 101 can be completely fitted with the inner wall surface of the groove 102.

[0040] For ease of explanation, the curved corner 201 of the core 200 can be defined as an R-corner, which can be supported by the groove 102. A groove pair includes two grooves 102, each groove 102 corresponding to an R-corner of the core 200, that is, the total number of grooves 102 is the same as the number of R-corners of the core 200.

[0041] It is understood that the groove 102 is part of the cell housing 100 and is directly formed on the inner wall of the cell housing 100. That is, the thickness of one portion of the inner wall of the cell housing 100 is greater than the thickness of another portion, thereby forming the groove 102. The thickness of the cell housing 100 can be in the direction from the external space to the interior of the receiving space 101.

[0042] In this embodiment, the recess 102 can be formed on the inner wall of the cell housing 100 by stamping, stretching, or injection molding. For example, the cell housing 100 with the recess 102 can be integrally molded by casting molten aluminum, which simplifies the manufacturing process and improves its integrity. For example, if the cell housing 100 is made of aluminum, during manufacturing, the inner portion of the aluminum housing can be stretched to form an integrated curved structure at the side corresponding to the rounded portion of the winding core 200, thereby forming the recess 102. By providing the recess 102 on the inner wall of the cell housing 100, i.e., the recess 102 is an integral part of the cell housing 100, this not only avoids the impact on the effective volume of the housing space 101 caused by the use of a separate support structure, but also improves the integrity of the cell housing 100 and simplifies the assembly process. Furthermore, compared to existing solutions that utilize separate support members, the cell housing 100 of this embodiment reduces the number of structural components, saves mold costs, reduces the complexity of the manufacturing process, and saves steps during the shell insertion process, thus saving costs in multiple aspects such as R&D, management, and manufacturing.

[0043] It can be seen that according to the embodiment of the present application, the battery cell shell 100 forms a groove 102 belonging to the battery shell 100 during the processing process. The groove 102 can be used to provide strong support to the corner portion 201 of the winding core 200 during the charging and discharging process, thereby preventing the battery cell from being unable to restrain the corner portion 201 on both sides during the charging and discharging process due to the gap between the corner portions 201, thereby improving the cycle performance and safety of the battery cell.

[0044] Therefore, according to the embodiment of the present application, the inner wall of the battery cell shell 100 is provided with at least one group of groove pairs, and the groove pair includes two spaced-apart and oppositely arranged grooves 102, which can not only support the corner portion 201 of the core 200 when the core 200 expands, thereby alleviating the problem of lithium deposition at the corner; but also ensure the volume of the core 200, increase the battery cell capacity, simplify the assembly process, and improve assembly efficiency.

[0045] According to one embodiment of the present application, Figures 2 to 4 As shown, the battery cell housing 100 includes: a first side plate 10, a second side plate 20, a third side plate 30, a fourth side plate 40, a bottom plate 50 and a cover plate 60, the first side plate 10 and the second side plate 20 are arranged opposite to each other in the first direction, the third side plate 30 and the fourth side plate 40 are arranged opposite to each other in the second direction, the third side plate 30 and the fourth side plate 40 are connected to the first side plate 10 and the second side plate 20 respectively, and any one of the third side plate 30 and the fourth side plate 40 has a groove 10 opening toward the other 2, the bottom plate 50, the first side plate 10, the second side plate 20, the third side plate 30, and the fourth side plate 40 enclose a receiving space 101. The first side plate 10, the second side plate 20, the third side plate 30, and the fourth side plate 40 enclose an open end 104 communicating with the receiving space 101. The cover plate 60 is mounted on the open end 104. The cover plate 60 is disposed opposite the bottom plate 50 in the third direction. The cover plate 60 is used to enclose the receiving space 101. The groove 102 extends from the bottom plate 50 toward the cover plate 60. The pair of grooves on the inner wall of the battery cell housing 100 may include two grooves 102 spaced apart and distributed in the second direction.

[0046] That is, in this embodiment, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40, the bottom panel 50, and the cover panel 60 may enclose a cell housing 100 and a receiving space 101. Furthermore, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40, and the bottom panel 50 may enclose an open end 104, which communicates with the receiving space 101. After the winding core 200 is installed in the receiving space 101 through the open end 104, the receiving space 101 may be closed by the cover panel 60. For example, the first side panel 10 and the second side panel 20 may be large and symmetrically arranged; the third side panel 30 and the fourth side panel 40 may be narrow and symmetrically arranged. Thus, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40, and the closed bottom panel 50 may form a semi-enclosed housing having an open end 104 at the top.

[0047] The first side panel 10 and the second side panel 20 are spaced apart and arranged opposite to each other in a first direction, and the third side panel 30 and the fourth side panel 40 are spaced apart and arranged opposite to each other in a second direction. The third side panel 30 and the fourth side panel 40 are respectively connected to the first side panel 10 and the second side panel 20. In other words, one end of the third side panel 30 can be connected to the first side panel 10, and the other end of the third side panel 30 can be connected to the second side panel 20. Similarly, one end of the fourth side panel 40 can be connected to the first side panel 10, and the other end of the fourth side panel 40 can be connected to the second side panel 20. The first side panel 10, the second side panel 20, the third side panel 30, and the fourth side panel 40 can enclose a receiving space 101 with both ends open. The bottom panel 50 can be located at one end of the receiving space 101, and the cover panel 60 can be located at the other end of the receiving space 101. The bottom panel 50 and the cover panel 60 can be arranged opposite to each other in the third direction. For example, the first side panel 10 and the second side panel 20 are spaced apart and arranged oppositely in the front-to-back direction, the third side panel 30 and the fourth side panel 40 are spaced apart and arranged oppositely in the left-to-right direction, and the cover panel 60 and the bottom panel 50 are spaced apart and arranged oppositely in the top-to-bottom direction. That is, the first side panel 10 has a rear inner wall, the second side panel 20 has a front inner wall, the third side panel 30 has a left inner wall, and the fourth side panel 40 has a right inner wall. Optionally, any two of the first, second, and third directions are perpendicular to each other. For example, the first direction is the X-axis direction, the second direction is the Y-axis direction, and the third direction is the Z-axis direction. By restricting the first, second, and third directions, it is advantageous to prepare a battery cell housing 100 of a specific shape, such as a rectangular battery cell housing 100.

[0048] In addition, either the third side panel 30 or the fourth side panel 40 has a groove 102 that opens toward the other. For example, the left inner wall has a groove 102, and the right inner wall has a groove 102. When the core 200 is installed in the receiving space 101 through the open end 104, the left end of the core 200 can be inserted into the groove 102 of the left inner wall, and the right end of the core 200 can be inserted into the groove 102 of the right inner wall. In addition, both the left and right ends of the core 200 have an arc-shaped corner portion 201, and the outer surface of the corner portion 201 can be connected to the arc-shaped inner wall surface of the groove 102, thereby supporting the corner portion 201. In addition, by providing a pair of grooves, the core 200 can be inserted into the groove 102 along the extension direction of the groove 102, which improves the assembly efficiency of the core 200 and is not easy to shift.

[0049] In this embodiment, the cell housing 100 is primarily composed of a first side panel 10, a second side panel 20, a third side panel 30, a fourth side panel 40, a bottom panel 50, and a cover panel 60. The shape of the cell housing 100 is roughly the same as the outer contour of most current cell casings, making it compatible with most commercially available winding cores 200, expanding its applicability. Furthermore, the grooves 102 are directly formed on the inner walls of the third and fourth side panels 30, 40, facilitating machining of the grooves 102 and ensuring the effective volume of the housing space 101, thereby increasing the cell capacity.

[0050] In some specific embodiments of this application, such as Figure 8 As shown, in the direction from the bottom plate 50 to the cover plate 60, the third side plate 30 and / or the fourth side plate 40 include: a first surface 71, a second surface 72 and a third surface 73, the first surface 71 has a groove 102, the second surface 72 is connected to the outer edge of the open end 104, the third surface 73 is connected to the first surface 71 and the second surface 72 respectively, the first surface 71 is located on the side of the second surface 72 close to the center line of the receiving space 101, the third surface 73 cooperates with the first surface 71 and the second surface 72 respectively to form a step portion, and the third surface 73 is a step surface.

[0051] That is to say, in this embodiment, the third side panel 30 alone may include the first surface 71, the second surface 72 and the third surface 73, the fourth side panel 40 alone may include the first surface 71, the second surface 72 and the third surface 73, or the third side panel 30 and the fourth side panel 40 may include the first surface 71, the second surface 72 and the third surface 73 respectively.

[0052] Among them, a groove 102 is provided on the first surface 71, and the extension direction of the groove 102 can be from the base plate 50 to the cover plate 60, for example, extending in the direction from bottom to top. Moreover, the extension directions of the second surface 72 and the first surface 71 are roughly the same, and both can extend in the direction from the base plate 50 to the cover plate 60.

[0053] Furthermore, the first surface 71 is located on a side of the second surface 72 that is closer to the centerline of the receiving space 101. That is, along the wall thickness direction of the battery case 100, the first surface 71 and the second surface 72 can be spaced apart and arranged, and the first surface 71 is closer to the interior of the battery case 100. Along the wall thickness direction of the battery case 100, one end of the third surface 73 is connected to the first surface 71, and the other end of the third surface 73 is connected to the second surface 72. That is, the third surface 73 can serve to connect the first surface 71 and the second surface 72.

[0054] In addition, the third surface 73 cooperates with the first surface 71 and the second surface 72 to form a stepped portion. The third surface 73 is a stepped surface, that is, the third surface 73 can extend generally along the wall thickness direction of the battery cell casing 100. For example, the first surface 71 and the second surface 72 extend from bottom to top, respectively, and the third surface 73 extends from left to right.

[0055] It should be noted that because the extended length of the groove 102 is shorter than the length of the third side panel 30 or the fourth side panel 40 in which the groove 102 is provided, for example, in the vertical direction, the length of the groove 102 is shorter than the length of the third side panel 30, and a gap exists between the open end 104 and the third surface 73. After the winding core 200 is installed in the groove 102, one end of the winding core 200 aligns with the bottom panel 50, while the other end of the winding core 200 aligns with the cover panel 60, with a height difference between the open end 104 and the core 200. This allows space for plastic, tabs, and other components to be placed on the top of the winding core 200.

[0056] For ease of explanation, Figure 3 As shown, the length of the groove 103 can be defined as H1, and the depth of the receiving space 101 can be defined as H2. Here, the groove and depth of the groove 103 refer to the direction from the bottom plate 50 to the open end 104. Due to the presence of the step, there is a difference ΔH between H1 and H2, ΔH = H2 - H1, and the ΔH range is 4mm to 12mm. Since the end of the winding core 200 can be flush with or lower than the end of the groove 103, interference between the groove 103 and the lower plastic of the cover plate 60 and the bottom support plate can be avoided.

[0057] In this embodiment, a step portion can be formed by matching the first surface 71, the second surface 72 and the third surface 73, so that there is a height difference between the end of the groove 102 and the open end 104, and space can be reserved for plastic, tabs, etc. at the top of the core 200.

[0058] According to one embodiment of the present application, the length of the groove 102 in the direction from the bottom plate 50 to the cover plate 60 is A. hThe length of the third side plate 30 or the fourth side plate 40 provided with the groove 102 is W h , 0.5≤A h / W h ≤0.98. For example, a groove 102 is provided on the third side plate 30, and the third side plate 30 and the groove 102 extend from bottom to top respectively, and the length of the groove 102 is A h , the length of the third side plate 30 is W h , 0.5≤A h / W h ≤0.98. In this embodiment, by setting 0.5≤A h / W h ≤0.98, for example, A h :W h The ratio is any one of 0.5, 0.6, 0.7, 0.8, 0.85, 0.9, 0.95 or 0.98, etc., or a range between any two of them.

[0059] Preferably, A h / W h The ratio is 0.95, at this time the groove 102 has the best support strength for the arc-shaped corner portion 201 of the winding core 200. In addition, when A h / W h When the ratio decreases, the weight energy density of the battery cell will be improved. At the same time, in some battery cells with a smaller expansion force of the core 200, the groove 102 can still provide a good support effect. For example, in some battery cells, due to the large size of the large surface, when the core 200 expands, the strength of the large surface to restrict the core 200 is greater. Therefore, the expansion force at the R corner is relatively weak, and then A h / W h The ratio can be smaller and can be set to 0.5, 0.6, 0.7, 0.8, etc. or a range between any two of them. When the large surface area of ​​the battery cell is small, when the winding core 200 expands, the expansion force of the corner portion 201 is large; therefore, it is necessary to set A h / W h The ratio is set to a relatively large value, such as 0.8, 0.9, 0.95, etc. or a range between any two of them. h / W h The larger the ratio, the better the support of the groove 102 on the R angle of the core 200, and the greater the expansion force that the R angle withstands.

[0060] According to an embodiment of the present application, the thickness of the bottom plate 50 is T1. In the second direction, the distance between the first surface 71 and the second surface 72 is T2. That is to say, the distance between the extension surfaces of the first surface 71 and the second surface 72 is T2; the thickness of the second surface 72 provided on the battery cell housing 100 is T3. That is to say, the distance between the outer surface of the third side plate 30 or the fourth side plate 40 provided with the second surface 72 and the second surface 72 is T3; an explosion-proof valve 90 is provided on the cover plate 60, the maximum pressure that the explosion-proof valve can withstand is P1, the maximum pressure that the connection position between the outer periphery of the cover plate 60 and the open end 104 can withstand is P2, and the maximum pressure that the third side plate 30 or the fourth side plate 40 provided with the second surface 72 can withstand is P3. Among them, T2≤T3<T1, T2 is [0.4T1, 0.75T1], and P1<P2≤P3. For example, T2 is 0.4T1, 0.45T1, 0.5T1, 0.55T1, 0.6T1, 0.65T1, 0.7T1 or 0.75T1, etc.

[0061] For the convenience of description, the third side plate 30 provided with the groove 102 is taken as an example for illustration below. The third side plate 30 includes a base body and a support portion provided on the base body, and the third side plate 30 is an integral part. The groove 102 is provided on the support portion. The outer surface of the base body is the outer surface of the battery cell housing 100, and the inner surface of the base body includes the second surface 72. The distance between the outer surface of the third side plate 30 and the second surface 72 is T3. The inner surface of the support portion is the inner surface of the groove 102, and the thickness of the support portion is the distance T2 between the extension surfaces of the first surface 71 and the second surface 72. It should be noted that the distance here refers to the distance along the thickness direction of the third side plate 30.

[0062] In addition, by defining T2≤T3<T1, T2 is [0.4T1, 0.75T1], and P1<P2≤P3, not only can the structural strength be guaranteed, but it can also be ensured that the setting of the groove 102 is not likely to affect the normal valve opening of the battery cell. In addition, since the groove 102 is an arc-shaped groove, in the width direction of the groove 102, the thickness of the third side plate 30 corresponding to the middle part of the groove 102 is smaller, and the thickness of the third side plate 30 corresponding to the end part of the groove 102 is larger, which can form a structure similar to a reinforcing rib. This not only improves the structural strength, but also can correspondingly improve the explosion-proof ability of the third side plate 30, so that it is not easy to crack at the position of the third side plate 30 provided with the groove 102 under corresponding safety tests (such as overcharge, thermal runaway, short circuit, extrusion and other safety tests), thereby improving the safety of the battery cell.

[0063] In some specific embodiments of the present application, the third side plate 30 and / or the fourth side plate 40 are hollow structures. That is, either the third side plate 30 alone can be a hollow structure, or the fourth side plate 40 alone can be a hollow structure, or both the third side plate 30 and the fourth side plate 40 can be hollow structures. In this embodiment, by adopting a hollow structure design, the weight of the battery cell housing 100 can be reduced, thereby ensuring the weight energy density of the battery cell. The provided groove 102 can support the corner portion 201 of the winding core 200 while alleviating problems such as lithium and sodium deposition at the corner portion 201 caused by the expansion of the winding core 200 during the battery cell cycle.

[0064] According to one embodiment of the present application, Figure 5 As shown, the inner wall surface of the cell housing 100 has multiple protrusions 105, with adjacent protrusions 105 spaced apart from each other. Each protrusion 105 is provided with a groove segment 103, and multiple groove segments 103 form a groove 102. For example, from top to bottom, the inner wall surface of the cell housing 100 has two protrusions 105, which are spaced apart from each other in the vertical direction. Each protrusion 105 has a groove segment 103 distributed from top to bottom, and two groove segments 103 form a groove 103.

[0065] That is to say, the integrated groove 102 can be divided into multiple groove segments 103, and the arc-shaped inner wall of each groove segment 103 can support the corner portion 201. The opening of the groove segment 103 has little effect on the weight of the battery cell shell 100, and the provision of the groove segment 103 can reduce the difficulty of producing the battery cell shell 100.

[0066] Furthermore, the number of protrusions 105 is not limited and can be one or more. For example, the thicker the cell housing 100 is, the greater the number of protrusions 105. Furthermore, the arrangement of the protrusions 105 is also not limited. Preferably, adjacent protrusions 105 are evenly spaced apart to improve the uniformity of the supporting force distribution.

[0067] The relationship between the groove section 103 and the groove 102 will be described in detail below by taking a groove 102 on the first surface 71 of the third side plate 30 as an example.

[0068] From bottom to top, a groove 102 is divided into n groove segments 103. Assuming the length of the third side plate 30 is W h , the length of a single groove segment 103 is A hi , where i is a positive integer from 1 to n, for example, A h1 、A h2 、A h3Represent the length of the first groove segment, the second groove segment and the third groove segment respectively. In addition, the lengths of adjacent groove segments 103 can be the same or different, which is not limited here. The total length of the groove 102 is set to A h , at this time A h =A h1 +A h2 +A h3 +……+A hn . A h / W h The ratio of can be any one of 0.2, 0.30, 0.40, 0.50 or the range between any two of them. In addition, 0.5≤A h / W h ≤0.98, no further details are given here.

[0069] According to one embodiment of the present application, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40, and the bottom panel 50 are connected as an integral part, which may be an integrated part connected and combined into one piece or an integrally formed part formed by injection molding, casting, stretching, etc. In this embodiment, by connecting the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40, and the bottom panel 50 as an integral part, the structural stability can be improved.

[0070] In some specific embodiments of the present application, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40 and the bottom panel 50 are made of the same material, and the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40 and the bottom panel 50 are formed into an integrally formed part. For example, the integrally formed part can be formed by stamping, stretching or injection molding, which can simplify the manufacturing process and improve the integrity. For example, the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40 and the bottom panel 50 are respectively aluminum parts, and the first side panel 10, the second side panel 20, the third side panel 30, the fourth side panel 40 and the bottom panel 50 can form a semi-enclosed aluminum shell with an open end 104 at the top. For another example, during the manufacturing process, an integral arc structure is formed inside the aluminum shell during the stretching process at the R portion position of the side corresponding to the winding core 200, that is, a groove 102 is formed.

[0071] According to one embodiment of the present application, Figure 1As shown, the cell housing 100 is rectangular in shape, and multiple pairs of grooves are arranged sequentially along the thickness direction of the cell housing 100. For example, the cell housing 100 is rectangular in shape, the first side panel 10 and the second side panel 20 are spaced apart and arranged oppositely in the front-to-back direction, the third side panel 30 and the fourth side panel 40 are spaced apart and arranged oppositely in the left-to-right direction, the cover panel 60 and the bottom panel 50 are spaced apart and arranged oppositely in the top-to-bottom direction, and the height of the third side panel 30 and the fourth side panel 40 is less than the width of the first side panel 10 and the second side panel 20. In this case, the thickness direction of the cell housing 100 is the front-to-back direction, and the depth direction of the accommodating space 101 is the top-to-bottom direction.

[0072] In this embodiment, multiple groove pairs are arranged sequentially along the thickness direction of the cell casing 100. For example, four groove pairs are included, specifically divided into a first groove pair, a second groove pair, a third groove pair, and a fourth groove pair. From bottom to top, the first groove pair, the second groove pair, the third groove pair, and the fourth groove pair are sequentially arranged. The end of each groove 102 is connected to the open end 104, meaning that the user can insert the four winding cores 200 into the corresponding grooves 102 through the open end 104. By adopting a rectangular shape for the cell casing 100 and sequentially arranging multiple groove pairs along the thickness direction of the cell casing 100, the design not only conforms to the outer contour of most current cell casings, but also allows for the simultaneous assembly of multiple winding cores 200.

[0073] like Figure 1 and Figure 2 As shown, the present application also discloses a battery cell, comprising: a battery cell housing 100 and a winding core 200. The battery cell housing 100 is the battery cell housing 100 of any of the above embodiments. The winding core 200 is installed in the battery cell housing 100, and the winding core 200 and the battery cell housing 100 are insulated and connected. The winding core 200 can be formed by winding a positive electrode sheet, a negative electrode sheet, and a separator.

[0074] Since the battery cell of the embodiment of the present application includes the battery cell shell 100 of any of the above embodiments, and the battery cell shell 100 of the embodiment of the present application has the advantages of improving the stability of the core 200 and ensuring the volume of the core 200, the battery cell of the embodiment of the present application also has the same advantages, such as large battery cell capacity, etc., which will not be elaborated here.

[0075] In some specific embodiments of the present application, the outer surface of the core 200 is covered with an insulating layer. For example, the outer surface of the core 200 is also wrapped with a Mylar film or an insulating film. That is to say, the core 200 and the battery cell housing 100 can be insulated and connected by coating the outer surface of the core 200 with an insulating layer, which has the advantages of being easy to implement and taking up little space. Optionally, the bottom of the core 200 can be pasted with a PP board, which is easy to operate and has strong stability. Optionally, the tabs on the core 200 are installed in the space between the step portion and the open end 104. Optionally, the cover plate 60 is designed with an explosion-proof valve, a pole, a lower plastic, etc. Optionally, as Figure 1 and Figure 2 As shown, the outside of the battery is also wrapped with a blue film 80.

[0076] In summary, according to the battery cell shell 100 of the embodiment of the present application, by setting a pair of grooves on the inner wall of the battery cell shell 100, not only can the support for the core 200 be improved, but also the volume of the core 200 can be guaranteed, thereby ensuring the capacity of the battery cell.

[0077] Although some specific embodiments of the present application have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A battery cell housing (100), characterized in that: The battery cell shell (100) defines a receiving space (101) therein, and the receiving space (101) can be used to install a winding core (200) having arc-shaped corner portions (201) at both ends. The inner wall of the battery cell shell (100) is provided with at least one pair of grooves, and the pair of grooves includes two grooves (102) that are spaced apart and arranged opposite to each other, and the inner wall surface of each groove (102) is an arc-shaped surface to support the corner portion (201).

2. The battery cell housing (100) according to claim 1, characterized in that include: A first side plate (10) and a second side plate (20), wherein the first side plate (10) and the second side plate (20) are arranged opposite to each other in a first direction; a third side plate (30) and a fourth side plate (40), the third side plate (30) and the fourth side plate (40) being arranged opposite to each other in a second direction, the third side plate (30) and the fourth side plate (40) being connected to the first side plate (10) and the second side plate (20) respectively, and either one of the third side plate (30) and the fourth side plate (40) having the groove (102) opening toward the other; a bottom plate (50), wherein the bottom plate (50), the first side plate (10), the second side plate (20), the third side plate (30) and the fourth side plate (40) enclose the receiving space (101); and the first side plate (10), the second side plate (20), the third side plate (30) and the fourth side plate (40) enclose an open end (104) communicating with the receiving space (101); A cover plate (60) is installed on the open end (104), the cover plate (60) is arranged opposite to the base plate (50) in a third direction, and is used to close the receiving space (101), and the groove (102) extends in a direction from the base plate (50) to the cover plate (60).

3. The battery cell housing (100) according to claim 2, characterized in that In the direction from the bottom plate (50) to the cover plate (60), the third side plate (30) and / or the fourth side plate (40) include: a first surface (71), wherein the first surface (71) has the groove (102); a second surface (72) connected to an outer edge of the open end (104); A third surface (73), the third surface (73) is connected to the first surface (71) and the second surface (72) respectively, the first surface (71) is located on the side of the second surface (72) close to the center line of the receiving space (101), the third surface (73) cooperates with the first surface (71) and the second surface (72) to form a step portion, and the third surface (73) is a step surface.

4. The battery cell housing (100) according to claim 3, characterized in that: In the direction from the bottom plate (50) to the cover plate (60), the length of the groove (102) is A h The length of the third side plate (30) or the fourth side plate (40) provided with the groove (102) is W h , 0.5≤A h / W h ≤0.

98.

5. The battery cell housing (100) according to claim 4, characterized in that: A h / W h is 0.

95.

6. The battery cell housing (100) according to claim 3, characterized in that: The thickness of the bottom plate (50) is T1. In the second direction, the distance between the first surface (71) and the second surface (72) is T2. The thickness of the second surface (72) provided on the battery cell housing (100) is T3. The cover plate (60) is provided with an explosion-proof valve (90). The maximum pressure that the explosion-proof valve can withstand is P1. The maximum pressure that the connection position between the outer periphery of the cover plate (60) and the open end (104) can withstand is P2. The maximum pressure that the third side plate (30) or the fourth side plate (40) provided with the second surface (72) can withstand is P3. Wherein, T2 ≤ T3 < T1, T2 is within the range of [0.4T1, 0.75T1], and P1 < P2 ≤ P3.

7. The battery cell housing (100) according to claim 2, characterized in that The third side plate (30) and / or the fourth side plate (40) is a hollow structure.

8. The battery cell housing (100) according to any one of claims 2 to 7, characterized in that: The first side plate (10), the second side plate (20), the third side plate (30), the fourth side plate (40) and the bottom plate (50) are connected as an integral part.

9. The battery cell housing (100) according to claim 1, characterized in that: The inner wall surface of the battery cell housing (100) has a plurality of protrusions (105). Two adjacent protrusions (105) are spaced apart. Each protrusion (105) is provided with a groove section (103). The plurality of groove sections (103) form a groove (102).

10. A battery cell, characterized in that: Comprising: A battery cell housing (100), wherein the battery cell housing (100) is the battery cell housing (100) according to any one of claims 1-9; A wound core (200), wherein the wound core (200) is installed in the battery cell housing (100), and the wound core (200) is insulatedly connected to the battery cell housing (100).

Images