Battery cell and battery

Abstract

The utility model relates to the technical field of batteries, in particular to a single battery and a battery. The battery monomer comprises a shell, a cover plate and a battery cell assembly, the shell comprises a bottom wall and a plurality of side walls surrounding the bottom wall, two end parts, far away from the bottom wall, of at least one group of two side walls positioned on two opposite sides are oppositely bent to form two bent parts respectively, the cover plate is arranged on an opening of the shell, and the battery cell assembly is arranged on the cover plate. An accommodating cavity is formed in an enclosed area among the cover plate, the plurality of side walls and the bottom wall; and the battery core assembly is arranged in the accommodating cavity. The single battery and the battery can prevent welding laser from easily irradiating the battery core assembly in the welding process.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to battery cells and batteries. Background Art

[0002] During the assembly process of the cover plate and the shell of the square shell battery, the cover plate and the inner cavity of the shell are of the same size. After the cover plate is aligned with the top opening of the shell, laser welding is performed with the top parallel to the overlapping gap area. Due to the gap between the cover plate and the shell, the welding laser can easily penetrate into the shell through the gap and damage the internal battery cell components. How to prevent the welding laser from easily irradiating the battery cell components during welding is a technical problem that needs to be solved in this field. Utility Model Content

[0003] In view of this, the present application provides a battery cell and a battery, which can prevent the welding laser from easily irradiating the battery cell components during the welding process.

[0004] In a first aspect, the present application provides a battery cell, comprising: a shell, comprising a bottom wall and a plurality of side walls arranged around the bottom wall, wherein at least one group of two side walls located on opposite sides are bent toward each other at two ends away from the bottom wall to form two bent portions respectively, and a plurality of ends of the plurality of side walls away from the bottom wall are enclosed to form a shell opening; a cover plate, arranged on the shell opening, the enclosed area between the cover plate, the plurality of side walls and the bottom wall forming a accommodating cavity; and a battery cell assembly, arranged in the accommodating cavity.

[0005] In combination with the first aspect, in a possible implementation, the number of the side walls is four, one pair of the oppositely arranged side walls are provided with the bending portion, and the other pair of oppositely arranged side walls are not provided with the bending portion, and the side walls without the bending portion are provided with connecting portions at both ends of the side away from the bottom wall, and the edges of the connecting portions are connected to the adjacent side walls provided with the bending portion; wherein the connecting portion is a notch structure or a folded edge structure.

[0006] In combination with the first aspect, in a possible implementation, the bending portions are provided on a plurality of the side walls, connecting portions are provided at both ends of the bending portions on a side away from the bottom wall, and the edges of the connecting portions of adjacent bending portions are connected; wherein the connecting portion is a notch structure or a folded edge structure.

[0007] In combination with the first aspect, in a possible implementation, the bending angle of the bending portion relative to a preset surface is a first angle θ1, and the first angle θ1 is any value between 5° and 85°; wherein the preset surface represents a plane perpendicular to the bottom wall.

[0008] In combination with the first aspect, in a possible implementation, a projection size of the bending portion on a preset surface is any value between 1 mm and 6 mm; wherein the preset surface represents a plane perpendicular to the bottom wall.

[0009] In combination with the first aspect, in a possible implementation manner, the thickness of the bent portion is less than or equal to the thickness of the side wall except the bent portion.

[0010] In combination with the first aspect, in a possible implementation, the side end surface of the cover plate includes a cover plate mating surface and a sunken surface that are connected to each other, the cover plate mating surface is used to dock with the end surface of the bending portion, and the sunken surface is located on the side of the cover plate mating surface facing the bottom wall.

[0011] In combination with the first aspect, in a possible implementation manner, the cover plate mating surface and the sunken surface form a second angle θ2, and the second angle θ2 is any value between 95° and 180°.

[0012] In combination with the first aspect, in a possible implementation, the cover plate mating surface includes a first mating surface and a second mating surface, one end of the second mating surface is connected to the first mating surface, and the end of the second mating surface away from the first mating surface is connected to the sunken surface, at least part of the first mating surface is connected to the top end surface of the bending portion away from the bottom wall, and at least part of the second mating surface is connected to the side wall surface of the bending portion adjacent to the top end surface; wherein, the second mating surface forms a third angle θ3 with the sunken surface, and the third angle θ3 is any value between 95° and 175°.

[0013] In a second aspect, the present application provides a battery, comprising the aforementioned battery cell.

[0014] The battery cell and battery provided in the embodiments of the present application include a shell, a cover plate and a cell assembly, the shell includes a bottom wall and a plurality of side walls arranged around the bottom wall, at least one group of two side walls located on opposite sides are bent toward each other at two ends away from the bottom wall to form two bent portions respectively, and in the process of welding the bent portion and the edge of the cover plate using a welding laser, the welding laser is irradiated along the bending direction of the bent portion, so that the side wall with the bent portion enables the irradiation direction of the welding laser to be aligned with the bent portion, and is obliquely arranged relative to the side wall or the cover plate, that is, the irradiation direction of the welding laser does not need to be perpendicular to the side wall or the cover plate for irradiation, that is, the irradiation direction of the welding laser has a certain degree of freedom, so it is difficult for the welding laser to penetrate the gap between the cover plate and the side wall to enter the accommodating cavity and irradiate the cell assembly, thereby avoiding the welding laser from damaging the cell assembly and optimizing the safety performance of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1Shown is a schematic structural diagram of a battery cell provided in one embodiment of the present application.

[0016] Figure 2 Shown is a schematic structural diagram of a shell provided in one embodiment of the present application.

[0017] Figure 3 Shown is a schematic diagram of the folding process of the bending portion provided in one embodiment of the present application.

[0018] Figure 4 Shown is a schematic diagram of the folding process of the bending portion provided in another embodiment of the present application.

[0019] Figure 5 The figure is a schematic structural diagram of a connection portion in a folded edge shape provided by an embodiment of the present application.

[0020] Figure 6 Shown is a partial schematic diagram of another embodiment of the present application in which the connecting portion is in a folded edge shape.

[0021] Figure 7 Shown is a partial schematic diagram of another embodiment of the present application in which the connecting portion is in a folded edge shape.

[0022] Figure 8 Shown is a partial schematic diagram of another embodiment of the present application in which the connecting portion is in a folded edge shape.

[0023] Fig. 9 Shown is a partial structural schematic diagram of a battery cell provided in one embodiment of the present application.

[0024] Fig.10 Shown is a partial structural schematic diagram of a battery cell provided in another embodiment of the present application.

[0025] Fig.11 Shown is a partial structural schematic diagram of a battery cell provided in another embodiment of the present application.

[0026] Fig.12 Shown is a partial structural schematic diagram of a battery cell provided in another embodiment of the present application.

[0027] Figure markings: 1-shell; 101-bottom wall; 102-side wall; 103-bending portion; 1031-top end surface; 1032-side end surface; 104-shell opening; 105-connecting portion; 2-cover plate; 201-cover plate mating surface; 2011-first mating surface; 2012-second mating surface; 202-sunk surface; 203-accommodating cavity; 3-preset surface. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] Exemplary battery cells are as follows:

[0030] Figure 1 Shown is a schematic structural diagram of a battery cell provided in one embodiment of the present application. Figure 2 The present application provides a battery cell. In one embodiment, as shown in FIG. Figure 1 and Figure 2 As shown, the battery cell comprises a shell 1, a cover plate 2 and a cell assembly. The shell 1 comprises a bottom wall 101 and a plurality of side walls 102 arranged around the bottom wall 101, at least one set of two side walls 102 located on opposite sides are bent towards each other at two ends away from the bottom wall 101 to form two bent portions 103 respectively, and the plurality of ends of the plurality of side walls 102 away from the bottom wall 101 are enclosed to form a shell opening 104. The cover plate 2 is arranged on the shell opening 104, and the enclosed area between the cover plate 2, the side walls 102 and the bottom wall 101 forms a receiving cavity 203, and the cell assembly is arranged in the receiving cavity 203.

[0031] When this embodiment is used, during the welding process of the side wall 102 and the cover plate 2, a welding laser is used to weld the bent portion 103 to the edge of the cover plate 2, and the welding laser is irradiated along the bending direction of the bent portion 103. In this way, the side wall 102 with the bent portion 103 enables the irradiation direction of the welding laser to be aligned with the bent portion 103, and is obliquely arranged relative to the side wall 102 or the cover plate 2, that is, the irradiation direction of the welding laser does not need to be perpendicular to the side wall 102 or the cover plate 2 for irradiation, that is, the irradiation direction of the welding laser has a certain degree of freedom, so it is difficult for the welding laser to penetrate the gap between the cover plate 2 and the side wall 102 into the accommodating cavity 203 and irradiate the battery cell assembly, thereby avoiding the welding laser from damaging the battery cell assembly and optimizing the safety performance of the battery single body.

[0032] It should be noted that the “plurality” mentioned herein can be understood as four or more, that is, the number of the side walls 102 can be four, five, six, etc.

[0033] In one embodiment, Figure 3 The figure shows a schematic diagram of the folding process of the bending portion provided by an embodiment of the present application. Figure 2 and Figure 3As shown, there are four side walls 102, one pair of oppositely arranged side walls 102 is provided with bending portions 103, and the other pair of oppositely arranged side walls 102 is not provided with bending portions 103, and the side walls 102 without bending portions 103 are provided with connecting portions 105 at both ends of the side away from the bottom wall 101, and the edges of the connecting portions 105 are connected to the adjacent side walls 102 provided with the bending portions 103.

[0034] In one embodiment, the connection portion 105 may be a notch structure or a folded edge structure, which can tightly connect the bent portion 103 to the side wall 102 without the bent portion 103. Specifically, Figure 4 FIG. 1 is a schematic diagram of the folding process of the bending portion 103 provided in another embodiment of the present application. Figure 3 and Figure 4 As shown, the connecting portion 105 may be a notch structure. Figure 5 The figure is a schematic structural diagram of a connection portion in a folded edge shape provided by an embodiment of the present application. Figure 6 The figure is a schematic structural diagram of another embodiment of the present application in which the connecting portion is in a folded edge shape. Figure 7 Shown is a partial schematic diagram of another embodiment of the present application in which the connecting portion is in a folded edge shape. Figure 8 FIG. 1 is a partial schematic diagram of another embodiment of the present application in which the connecting portion is in a folded shape. Figures 5 to 8 As shown, the connection portion 105 may be a folded edge structure. The connection portion 105 being a notch structure or a folded edge structure is described in detail below.

[0035] like Figure 3 As shown, in one embodiment, there are four side walls 102, two opposite side walls 102 are provided with bending portions 103, and the other two opposite side walls 102 are not provided with bending portions 103. The side walls 102 not provided with the bending portions 103 are provided with connecting portions 105, and the connecting portions 105 are notch structures, and the connecting portions 105 are used to dock with the bending portions 103. The connecting portions 105 with notch structures can be considered as notch structures formed by removing a piece from the side walls 102 not provided with the bending portions 103, so that the bending portions 103 can dock with the connecting portions 105 of the side walls 102 not provided with the bending portions 103 after being bent, so that the bending portions 103 and the side walls 102 not provided with the bending portions 103 are tightly connected to form a sealing structure, thereby improving the sealing performance of the battery cell.

[0036] like Figure 4As shown, there are four side walls 102, and each of the four side walls 102 is provided with a bending portion 103. The two ends of the bending portion 103 away from the bottom wall 101 are provided with connecting portions 105, and the edges of the connecting portions 105 of adjacent bending portions 103 are connected. Each connecting portion 105 is a notch structure, which can align the edges of adjacent bending portions 103, so that the adjacent bending portions 103 are tightly connected to form a sealing structure, thereby improving the sealing of the battery cell.

[0037] It should be noted that when the number of side walls 102 is greater than four, the multiple side walls 102 are provided with a bending portion 103 or one group of relatively arranged side walls 102 is provided with the aforementioned bending portion 103, and the connecting portion 105 is a notch structure. For the specific structure and beneficial effects, please refer to the relevant content when the number of the aforementioned side walls 102 is four, and no further details will be given here.

[0038] like Figure 5 As shown, there are four side walls 102, and bending portions 103 are provided on all four side walls 102. Connecting portions 105 are provided at both ends of the bending portions 103 away from the bottom wall 101, and the edges of the connecting portions 105 of adjacent bending portions 103 are connected. Each connecting portion 105 is a folded edge structure, that is, the connecting portion 105 between adjacent bending portions 103 is bent (the specific bending direction will be introduced later). In this way, the edges between adjacent bending portions 103 can be tightly connected, and the four side walls 102 are an integrated structure, so as to form a sealing structure with better sealing performance, thereby improving the sealing of the battery cell.

[0039] In one embodiment, there are four side walls 102, of which two opposite side walls 102 are provided with bending portions 103, and the other two opposite side walls 102 are not provided with bending portions 103. The two ends of the side wall 102 not provided with the bending portion 103 away from the bottom wall 101 are provided with connecting portions 105, and the edges of the connecting portions 105 are connected to the adjacent side walls 102 provided with the bending portions 103. Each connecting portion 105 is a folded edge structure, that is, the connecting portion 105 between adjacent bending portions 103 is bent, so that the edges between adjacent bending portions 103 can be closely connected, and the four side walls 102 are an integrated structure, so as to form a sealing structure with better sealing performance, thereby improving the sealing performance of the battery cell.

[0040] It should be noted that when the number of side walls 102 is greater than four, the multiple side walls 102 are provided with a bending portion 103 or one group of relatively arranged side walls 102 is provided with the aforementioned bending portion 103, and the connecting portion 105 is a folded edge structure. For the specific structure and beneficial effects, please refer to the relevant content when the number of the aforementioned side walls 102 is four, and no further details will be given here.

[0041] like Figure 6 As shown, taking one of the connecting parts 105 as an example, Figure 6 The connecting portion 105 is a folded edge structure, which is an inward folding structure, that is, the connecting portion 105 between adjacent bent portions 103 is bent toward the shell opening 104 or toward the accommodating cavity 203, so that the inward folded portion of the connecting portion 105 is located in the shell opening 104 or the accommodating cavity 203. In this way, under the premise of ensuring the tight connection between adjacent bent portions 103, the inward folded portion of the connecting portion 105 will not affect the subsequent laser welding, which can effectively ensure the flatness of the laser welding point and improve the welding quality.

[0042] like Figure 7 and Figure 8 As shown, taking one of the connecting parts 105 as an example, Figure 7 and Figure 8 The connection portion 105 in the embodiment is a folded edge structure, which is an outward folded structure, that is, the connection portion 105 between adjacent bent portions 103 is bent in a direction away from the housing opening 104 or away from the accommodating cavity 203, and the outward folded portion of the connection portion 105 is located outside the housing 1. Before laser welding, the outward folded portion of the connection portion 105 can be welded to the outside of the bent portion 103 to prevent the outward folded portion of the connection portion 105 from affecting the subsequent laser welding quality.

[0043] It should be noted that Figure 7 and Figure 8 The difference is that Figure 7 The folded parts of the middle connecting part 105 are all welded to the outside of one of the bent parts 103. Figure 8 The middle connecting portion 105 is divided into two parts by the outward folded portion, which are respectively welded to the outer sides of the two adjacent bending portions 103. Figure 7 or Figure 8 The outward folding structure shown.

[0044] Fig. 9 FIG. 1 is a partial structural diagram of a battery cell provided by an embodiment of the present application. Fig. 9 As shown, the bending angle of the bending portion 103 relative to the preset surface 3 (a plane perpendicular to the bottom wall 101) is a first angle θ1, and the first angle θ1 is any value between 5° and 85°. It should be understood that if the first angle θ1 is too small, then the height direction ( Fig. 9The distance in the direction indicated by the arrows C and D in the middle (in the direction indicated by the arrows C and D) is long, resulting in an excessive distance between the battery cell assembly in the accommodating cavity 203 and the cover plate 2, which wastes the space of the accommodating cavity 203 and reduces the space utilization rate; if the first angle θ1 is too large, the bent portion 103 will intrude more into the accommodating cavity 203, and it is easy to interfere with the battery cell assembly in the accommodating cavity 203, affecting the safety performance of the battery cell assembly. Therefore, the value range of the first angle θ1 is limited to 5° to 85°, so that it can avoid wasting the space of the accommodating cavity 203 and prevent the bent portion 103 from interfering with the battery cell assembly in the accommodating cavity 203.

[0045] In one embodiment, the first angle θ1 may be 5°, 50°, 85°, etc.

[0046] In one embodiment, the projection size of the bending portion 103 on the preset surface 3 (a plane perpendicular to the bottom wall 101) is any value between 1 mm and 6 mm. It should be understood that if the projection size of the bending portion 103 on the preset surface 3 is too long, then the height direction ( Fig. 9 If the distance in the direction indicated by arrows C and D in the middle is too long, the distance between the battery cell assembly in the accommodating cavity 203 and the cover plate 2 is too large, which wastes the space of the accommodating cavity 203 and reduces the space utilization rate; if the projection size of the bent portion 103 on the preset surface 3 is too short, the bent portion 103 will invade the accommodating cavity 203 more, and it is easy to interfere with the battery cell assembly in the accommodating cavity 203, affecting the safety performance of the battery cell assembly. Therefore, the value range of the projection size of the bent portion 103 on the preset surface 3 is limited to 1mm to 6mm, so that it can avoid wasting the space of the accommodating cavity 203 and prevent the bent portion 103 from interfering with the battery cell assembly in the accommodating cavity 203.

[0047] Fig.10 Shown is a partial structural schematic diagram of a battery cell provided in another embodiment of the present application. Fig.11 FIG. 1 is a partial structural diagram of a battery cell provided by another embodiment of the present application. Figures 9 to 11 As shown, the side end surface of the cover plate 2 includes a cover plate mating surface 201 and a sunken surface 202. The cover plate mating surface 201 is used to butt with the end surface of the bent portion 103, and the sunken surface 202 is located on the side of the cover plate mating surface 201 facing the bottom wall 101. It should be understood that when laser welding is performed on the cover plate mating surface 201 and the end surface of the bent portion 103, the sunken surface 202 located below the cover plate mating surface 201 can block the welding laser to a certain extent, so that the welding laser cannot face the battery cell assembly directly, thereby avoiding laser leakage and causing ablation and short circuit of the battery cell assembly.

[0048] like Fig. 9 and Fig.10As shown, specifically, the cover plate mating surface 201 and the sunken surface 202 form a second angle θ2, and the second angle θ2 is any value between 95° and 180°. It should be understood that if the second angle θ2 is too small, the sunken surface 202 may interfere with the bent portion 103, affecting the tight connection between the bent portion 103 and the cover plate mating surface 201, and affecting the overall sealing of the battery cell 1. Therefore, the value range of the second angle θ2 is limited to 95° to 180°, so that the interference between the sunken surface 202 and the bent portion 103 can be avoided.

[0049] In one embodiment, the second angle θ2 may be selected to be 95°, 150°, 180°, etc.

[0050] like Fig. 9 As shown, in actual applications, the second angle θ2 between the cover mating surface 201 and the sunken surface 202 is preferably in the range of 95° to 175°. In this way, the sunken surface 202 has a better blocking effect on the welding laser, and can effectively block the incident path of the welding laser, so that the welding laser cannot be directly facing the battery cell assembly, avoiding laser leakage and causing ablation and short circuit of the battery cell assembly.

[0051] In one embodiment, if Fig.10 As shown, the cover mating surface 201 and the sunken surface 202 can also be 180°, that is, the cover mating surface 201 and the sunken surface 202 can be located in the same plane. Compared with the solution in which the cover mating surface 201 and the sunken surface 202 are at an obtuse angle, the processing is simpler and the production efficiency is higher.

[0052] In one embodiment, if Fig.11 As shown, the cover plate mating surface 201 includes a first mating surface 2011 and a second mating surface 2012, one end of the second mating surface 2012 is connected to the first mating surface 2011, and the end of the second mating surface 2012 away from the first mating surface 2011 is connected to the sunken surface 202, at least part of the first mating surface 2011 is connected to the top end surface 1031 of the bending portion 103 away from the bottom wall 101, and at least part of the second mating surface 2012 is connected to the side end surface 1032 in the bending portion 103 adjacent to the top end surface 1031.

[0053] It should be noted that part of the top end surface 1031 and the side end surface 1032 of the bending portion 103 is clamped at the right angle where the first mating surface 2011 and the second mating surface 2012 intersect, which can improve the connection stability between the bending portion 103 and the cover plate mating surface 201.

[0054] It should be understood that since the sunken surface 202 is connected to the end of the second mating surface 2012 away from the first mating surface 2011, the sunken surface 202 is located on the side of the second mating surface 2012 facing the bottom wall 101, which can block the welding laser. Fig.11 As shown, the second mating surface 2012 and the sunken surface 202 form a third angle θ3, and the third angle θ3 is any value between 95° and 175°. In this way, the sunken surface 202 has a better blocking effect on the welding laser, and can effectively block the incident path of the welding laser, so that the welding laser cannot directly hit the battery cell assembly, causing laser leakage and causing ablation and short circuit of the battery cell assembly.

[0055] In one embodiment, the angle between the first mating surface 2011 and the second mating surface 2012 may be a right angle, an acute angle, an obtuse angle, etc.

[0056] In one embodiment, the third angle θ3 may be selected to be 95°, 150°, 175°, etc.

[0057] Fig.12 This is a partial structural diagram of a battery cell provided by another embodiment of the present application. Fig.12 As shown, the thickness of the bending portion 103 is smaller than the thickness of the side wall 102 except the bending portion 103 , so that the bending portion 103 is more likely to bend, thereby improving the working efficiency of bending the bending portion 103 .

[0058] In one embodiment, the thickness of the bending portion 103 may also be equal to the thickness of the side wall 102 except the bending portion 103. In this way, compared with the solution in which the thickness of the bending portion 103 is less than the thickness of the side wall 102 except the bending portion 103, the strength of the bending portion 103 can be ensured to be basically the same as the strength of the side wall 102 except the bending portion 103, which is beneficial to ensuring the overall structural strength of the shell 1.

[0059] An exemplary battery is as follows:

[0060] The present application provides a battery, which includes the aforementioned battery cell and has all the functions of the aforementioned battery cell. The beneficial effects of the battery can refer to the beneficial effects of the aforementioned battery cell.

[0061] In one embodiment, the battery may include a battery module or a battery pack.

[0062] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0063] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0064] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0065] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features of this utility model.

[0066] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: A shell (1) comprises a bottom wall (101) and a plurality of side walls (102) arranged around the bottom wall (101), wherein two ends of at least one group of two side walls (102) located on opposite sides away from the bottom wall (101) are bent towards each other to form two bent portions (103) respectively, and a plurality of ends of the plurality of side walls (102) away from the bottom wall (101) are surrounded to form a shell opening (104); a cover plate (2) disposed on the shell opening (104), wherein the enclosed area between the cover plate (2), the plurality of side walls (102) and the bottom wall (101) forms a receiving cavity (203); and The battery cell assembly is arranged in the accommodating cavity (203).

2. The battery cell according to claim 1, characterized in that: The number of the side walls (102) is four, wherein a pair of the side walls (102) arranged opposite to each other are provided with the bending portion (103), and the other pair of the side walls (102) arranged opposite to each other are not provided with the bending portion (103), and the two ends of the side walls (102) not provided with the bending portion (103) away from the bottom wall (101) are provided with connecting portions (105), and the edges of the connecting portions (105) are connected to the adjacent side walls (102) provided with the bending portion (103); Wherein, the connecting portion (105) is a notch structure or a folded edge structure.

3. The battery cell according to claim 1, characterized in that: The plurality of side walls (102) are each provided with the bending portion (103), and connecting portions (105) are provided at both ends of the bending portion (103) on a side away from the bottom wall (101), and the edges of the connecting portions (105) of adjacent bending portions (103) are connected; Wherein, the connecting portion (105) is a notch structure or a folded edge structure.

4. The battery cell according to claim 1, characterized in that: The bending angle of the bending portion (103) relative to the preset surface (3) is a first angle θ1, and the first angle θ1 is any value between 5° and 85°; wherein the preset surface represents a plane perpendicular to the bottom wall (101).

5. The battery cell according to claim 1, characterized in that: The projection size of the bent portion (103) on the preset surface (3) is any value between 1 mm and 6 mm; wherein the preset surface represents a plane perpendicular to the bottom wall (101).

6. The battery cell according to claim 1, characterized in that: The thickness of the bent portion (103) is less than or equal to the thickness of the side wall (102) other than the bent portion (103).

7. The battery cell according to any one of claims 1 to 6, characterized in that: The side end surface of the cover plate (2) comprises a cover plate mating surface (201) and a sunken surface (202) which are connected to each other, the cover plate mating surface (201) being used to butt joint with the end surface of the bent portion (103), and the sunken surface (202) being located on the side of the cover plate mating surface (201) facing the bottom wall (101).

8. The battery cell according to claim 7, characterized in that: The cover plate matching surface (201) and the sunken surface (202) form a second angle θ2, and the second angle θ2 is any value between 95° and 180°.

9. The battery cell according to claim 7, characterized in that: The cover plate mating surface (201) comprises a first mating surface (2011) and a second mating surface (2012), one end of the second mating surface (2012) is connected to the first mating surface (2011), and one end of the second mating surface (2012) away from the first mating surface (2011) is connected to the sunken surface (202), at least part of the first mating surface (2011) is connected to the top end surface (1031) of the bending portion (103) away from the bottom wall (101), and at least part of the second mating surface (2012) is connected to the side end surface (1032) of the bending portion (103) adjacent to the top end surface; The second mating surface (2012) and the sunken surface (202) form a third angle θ3, and the third angle θ3 is any value between 95° and 175°.

10. A battery, characterized in that: include: A battery cell as claimed in any one of claims 1 to 9.

Images