Battery monomer, battery and electric device

Abstract

The utility model is suitable for the technical field of batteries, and provides a single battery, a battery and a power utilization device, the power utilization device comprises the single battery or the battery, the battery comprises the single battery, and the single battery comprises an electrode assembly, a shell and an end cover; the shell comprises a shell body and an end structure arranged at the end, in the first direction, of the shell body, at least part of the electrode assembly is arranged in the shell body, a groove is formed in the peripheral wall of the end structure, the groove wall of the groove forms a bent part, and the first direction is perpendicular to the circumferential direction of the groove; at least part of the end cover and at least part of the electrode assembly are respectively arranged at two opposite ends of the bending part along the first direction; the battery monomer further comprises a reinforcing piece which is at least partially arranged on the bending part, and / or the structural strength of the bending part is greater than that of the shell body. Therefore, the problem of mutual pulling of the bending parts can be improved, and the problem that fatigue cracks or even fractures are generated on the bending parts can be further improved.

Description

Technical Field

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

[0002] In the related art, a battery cell may include a shell, an end cap, and an electrode assembly. At least part of the electrode assembly is disposed in the shell, and the end cap is disposed at the end of the shell and encapsulates the electrode assembly together with the shell. The outer peripheral wall of the shell is recessed to form a groove, so that the inner peripheral wall of the shell protrudes to form a bent portion to limit the electrode assembly and the end cap.

[0003] In some cases, the two walls of the bent portion facing each other along the first direction are prone to relative movement, so that the bent portions pull each other, resulting in fatigue cracks or even fractures. That is, the portion of the housing at the groove is at risk of fatigue cracks or even fractures. Utility Model Content

[0004] In view of the above problems, the embodiments of the present application provide a battery cell, a battery and an electrical device, which can improve the technical problem that the part of the shell at the groove has the risk of fatigue cracks or even breakage.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, including:

[0006] Electrode assembly;

[0007] The shell comprises a shell body and an end structure arranged at an end of the shell body along a first direction, at least part of the electrode assembly is arranged in the shell body, an outer peripheral wall of the end structure is provided with a groove arranged along the circumferential direction, the groove wall of the groove constitutes a bent portion arranged in a bent direction, and the first direction is perpendicular to the circumferential direction of the groove;

[0008] An end cap, at least a portion of the end cap and at least a portion of the electrode assembly are respectively disposed at two opposite ends of the bent portion along the first direction;

[0009] Wherein, the battery cell further includes a reinforcement member at least partially disposed at the bent portion, and / or the structural strength of the bent portion is greater than the structural strength of the shell body.

[0010] The battery cell provided in the embodiment of the present application is provided with at least one of the following two solutions: the first is to provide at least part of the reinforcement member at the bending portion; the second is to provide the structural strength of the bending portion to be greater than the structural strength of the shell body, so that the difficulty of the relative movement of the two walls of the bending portion relative to each other along the first direction can be increased, thereby reducing the amplitude of the relative movement of the two walls of the bending portion relative to each other along the first direction, so as to improve the problem of mutual pulling of the two walls of the bending portion relative to each other along the first direction, and further improve the problem of fatigue cracks or even fractures of the bending portion. That is, the risk of fatigue cracks or even fractures of the part of the shell at the groove can be reduced, so as to improve the reliability of the battery cell.

[0011] In some embodiments, the bending portion includes a first wall and a second wall opposite to each other along a first direction, and a connecting portion connecting the first wall and the second wall; the first wall and the second wall are respectively bent relative to the connecting portion;

[0012] A reinforcement member is provided at least one of a connection point between the first wall and the connection part, a connection point between the second wall and the connection part, and the connection part.

[0013] In this way, the structural strength of the bending portion can be enhanced, and the problem of fatigue cracks or even fractures of the bending portion can be improved.

[0014] In some embodiments, the connecting portion, the first wall, and the second wall are respectively provided with reinforcement members.

[0015] In this way, the difficulty of relative movement of the two walls of the bending portion along the first direction can be increased, thereby effectively improving the mutual pulling problem of the two walls of the bending portion along the first direction, and further improving the problem of fatigue cracks or even fractures of the bending portion.

[0016] In some embodiments, the reinforcement member includes a first reinforcement member, at least a portion of which is disposed on an inner wall of the groove;

[0017] And / or, the reinforcement member includes a second reinforcement member, and at least a portion of the second reinforcement member is arranged on the outer wall of the bending portion away from the groove.

[0018] Such an arrangement makes it very flexible to arrange the reinforcement member on the bending portion.

[0019] In some embodiments, the end structure further includes a third wall, which is connected to the end of the bend portion away from the shell body along the first direction and at least partially surrounds at least part of the outer periphery of the end cover, and part of the reinforcement is disposed on the third wall.

[0020] By arranging a reinforcement on the third wall, so that both the bending portion and the third wall of the end structure are provided with reinforcements, the overall structural strength of the end structure can be improved. This can improve the problem of mutual pulling between the two walls opposite to each other along the first direction of the bending portion, and further improve the problem of fatigue cracks or even breakage of the bending portion.

[0021] In some embodiments, the reinforcement member includes a first reinforcement member, a portion of which is disposed on an outer wall of the third wall;

[0022] And / or, the reinforcement member includes a second reinforcement member, and a portion of the second reinforcement member is disposed on the inner wall of the third wall.

[0023] Such an arrangement makes it very flexible to arrange the reinforcement member on the third wall.

[0024] In some embodiments, the reinforcement member satisfies the following relationship:

[0025] 0<T2 / T1≤5;

[0026] Among them, T1 is the wall thickness of the shell body, and T2 is the wall thickness of the reinforcement.

[0027] By adopting the above technical solution, the wall thickness of the reinforcement can be within a reasonable range, so that the reinforcement has a greater structural strength to improve the structural strength of the bending portion without occupying too much space in the battery cell, thereby enabling the battery cell to have a better energy density.

[0028] In some embodiments, 0.2≤T2 / T1<2.

[0029] Such a configuration allows the reinforcement to have a larger wall thickness, thereby having a greater structural strength, thereby effectively improving the structural strength of the bent portion, thereby improving the problem of mutual pulling of the bent portions, and further improving the problem of fatigue cracks or even fractures of the bent portions. In addition, the wall thickness of the reinforcement is within a reasonable range, and will not occupy too much space in the battery cell, thereby enabling the battery cell to have a better energy density.

[0030] In some embodiments, at least a portion of the bending portion has a wall thickness greater than that of the shell body, and / or at least a portion of the bending portion is made of a material different from that of the shell body.

[0031] By adopting at least one of the two solutions that the wall thickness of at least part of the bending portion is greater than the wall thickness of the shell body, and the material of at least part of the bending portion is different from the material of the shell body, the structural strength of the bending portion can be made greater than the structural strength of the shell body. In this way, the difficulty of relative movement of the two walls of the bending portion relative to each other along the first direction can be increased to reduce the amplitude of relative movement, thereby improving the problem of the two walls of the bending portion relative to each other along the first direction pulling each other, reducing the risk of fatigue cracks or even fractures in the part of the shell at the groove, and improving the reliability of the battery cell.

[0032] In some embodiments, the bend satisfies the following relationship:

[0033] 0<T3 / T1≤5;

[0034] Among them, T1 is the wall thickness of the shell body, and T3 is the wall thickness of the bending part.

[0035] By adopting the above technical solution, the wall thickness of the bending portion can be within a reasonable range, so that the bending portion will not occupy too much space in the battery cell while having a certain structural strength, thereby allowing the battery cell to have a better energy density.

[0036] In some embodiments, 0<T3 / T1≤2.

[0037] Such an arrangement allows the wall thickness of the bent portion to be within a reasonable range, so that the bent portion will not occupy too much space in the battery cell while having a certain structural strength, thereby allowing the battery cell to have a better energy density.

[0038] In some embodiments, 1.1≤T3 / T1.

[0039] By such an arrangement, the wall thickness of the bending portion is greater than the wall thickness of the shell body. Compared with the shell body, the structural strength of the bending portion can be greater, which can increase the difficulty of relative movement of the two walls of the bending portion opposite to each other along the first direction, that is, improve the pulling problem of the two walls of the bending portion opposite to each other along the first direction, and further improve the problem of fatigue cracks or even fractures of the bending portion.

[0040] In some embodiments, the end structure also includes a third wall, which is connected to the end of the bending portion along the first direction away from the shell body, and at least partially surrounds at least part of the outer periphery of the end cover. The wall thickness of the bending portion and the wall thickness of the third wall are both greater than the wall thickness of the shell body.

[0041] In this way, compared with the solution in which only the wall thickness of the bending portion is greater than the wall thickness of the shell body, there is no need to strictly position the portion with increased wall thickness, that is, there is no need to divide the bending portion in advance, which can simplify the processing operation of increasing the wall thickness of the bending portion.

[0042] In some embodiments, the end structure also includes a third wall, which is connected to the end of the bending portion along the first direction away from the shell body, and at least partially surrounds at least part of the outer periphery of the end cover. The material of the bending portion and the material of the third wall are different from the material of the shell body.

[0043] In this way, compared with the solution in which only the structural strength of the bending portion is greater than the structural strength of the shell body, there is no need to strictly position the portion with increased structural strength, that is, there is no need to divide the bending portion in advance. In this way, the bending portion and the third wall can be made of the same material, which can simplify the processing operation of the battery cell.

[0044] In a second aspect, an embodiment of the present application provides a battery, including a battery cell.

[0045] The battery provided in the embodiment of the present application, by adopting the battery cell involved above, can reduce the risk of fatigue cracks or even breakage of the portion of the shell at the groove, thereby improving the reliability of the battery cell and further improving the reliability of the battery.

[0046] In a third aspect, an embodiment of the present application provides an electrical device, including a battery cell or a battery.

[0047] The electrical device provided in the embodiment of the present application, by adopting the battery cell or battery involved above, can reduce the risk of fatigue cracks or even breakage of the shell portion at the groove, thereby improving the reliability of the battery cell and further improving the reliability of the electrical device.

[0048] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0050] Figure 1 A schematic diagram of a vehicle provided for some embodiments of the present application;

[0051] Figure 2 An exploded schematic diagram of a battery provided in some embodiments of the present application;

[0052] Figure 3A three-dimensional schematic diagram of a battery cell provided in some embodiments of the present application;

[0053] Figure 4 for Figure 3 Section view along AA;

[0054] Figure 5 for Figure 4 The enlarged view of point B in the middle;

[0055] Figure 6 A cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0056] Figure 7 for Figure 6 Enlarged view of point C in the middle;

[0057] Figure 8 A cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0058] Fig. 9 for Figure 8 The enlarged view of point D in the middle;

[0059] Fig.10 A cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0060] Fig.11 for Fig.10 Enlarged view of point E in the middle;

[0061] Fig.12 A cross-sectional view of a battery cell provided for some other embodiments of the present application;

[0062] Fig.13 for Fig.12 Enlarged view of point F in the middle.

[0063] Among them, the reference numerals in the figure are:

[0064] 1000-vehicle; 100-battery; 200-controller; 300-motor; 10-battery cell; 20-casing; 201-accommodation space; 21-first part; 22-second part; 11-electrode assembly; 12-shell; 1201-groove; 121-shell body; 122-end structure; 1221-bending portion; 12211-first wall; 12212-second wall; 12213-connecting portion; 1222-third wall; 13-end cover; 14-reinforcement; 14a-first reinforcement; 14b-second reinforcement; T1-wall thickness of shell body; T2-wall thickness of reinforcement; T3-wall thickness of bending portion; Z-first direction; Y-circumferential direction. DETAILED DESCRIPTION

[0065] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0066] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0067] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0068] In the description of the present application, "plurality" means more than two, and unless otherwise clearly and specifically defined, "more than two" includes two. Accordingly, "multiple groups" means more than two groups, including two groups.

[0069] In the description of this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0070] In the description of this application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, in this application, the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0071] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0072] In the related art, a battery cell may include a housing, an end cap and an electrode assembly. At least a portion of the electrode assembly is disposed in the housing, and the end cap is disposed at an end of the housing and encapsulates the electrode assembly together with the housing.

[0073] In some cases, the outer peripheral wall of the shell is recessed to form a groove, so that the inner peripheral wall of the shell protrudes to form a bent portion to limit the electrode assembly and the end cap. It can be understood that the groove wall of the groove constitutes a bent portion. Specifically, the end cap is arranged at the end of the shell along the first direction, and at least part of the electrode assembly and at least part of the end cap are respectively limited at opposite ends of the bent portion along the first direction.

[0074] During use, the battery cell will experience multiple charge and discharge cycles, causing the internal air pressure of the battery cell to fluctuate, thereby squeezing the bending structure; when the battery cell is in a vibrating condition, the electrode assembly, end cap and other structures will squeeze the bending structure. As a result, the two walls of the bending part that are opposite to each other along the first direction are prone to relative movement, causing the bending parts to pull each other, resulting in fatigue cracks or even fractures. That is, the part of the shell at the groove is at risk of fatigue cracks or even fractures.

[0075] Based on the above considerations, the embodiments of the present application provide a battery cell, a battery, and an electrical device. By setting at least part of the reinforcement at the bending portion, and / or setting the structural strength of the bending portion to be greater than the structural strength of the shell body, the difficulty of the relative movement of the two walls of the bending portion relative to each other along the first direction can be increased, thereby reducing the amplitude of the relative movement of the two walls of the bending portion relative to each other along the first direction, so as to improve the problem of mutual pulling of the two walls of the bending portion relative to each other along the first direction, and further improve the problem of fatigue cracks or even fractures of the bending portion. That is, the risk of fatigue cracks or even fractures in the part of the shell at the groove can be reduced, so as to improve the reliability of the battery cell.

[0076] In some embodiments, the battery cells involved in the embodiments of the present application can be used in electrical devices that use battery cells or batteries as power sources, and the batteries involved in the embodiments of the present application can be used in electrical devices that use batteries as power sources.

[0077] The electrical devices involved in the embodiments of the present application may be, but are not limited to, mobile phones, tablets, laptops, electric toys, electric tools, battery cars, vehicles, ships, spacecraft, and the like. Among them, electric toys may include fixed or mobile electric toys, for example, game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like. According to the power source, the vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like. According to the drive mode, the vehicle may be a front-wheel drive vehicle, a rear-wheel drive vehicle, or a four-wheel drive vehicle.

[0078] In other embodiments, the battery cells and batteries involved in the embodiments of the present application may also be used in energy storage devices, wherein the energy storage devices may be energy storage containers, energy storage cabinets, and the like.

[0079] The battery involved in the embodiment of the present application can be a single physical module including one or more battery cells to provide higher voltage and capacity. When there are multiple battery cells, the multiple battery cells are connected in series, in parallel or in hybrid connection through a busbar component. Hybrid connection means that multiple battery cells are connected in both series and in parallel.

[0080] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module. As an example, the multiple battery cells may be fixed by cable ties or the like to form a battery module. As an example, the multiple battery cells may also be fixed by end plates, side plates, or the like to form a battery module.

[0081] In other embodiments, the battery may be a battery pack, which may include a box and a battery cell. As an example, the battery cell may be directly accommodated in the box. As an example, the battery cell may also be formed into a battery module first and then accommodated in the box.

[0082] The battery cell involved in the embodiments of the present application refers to the smallest unit for storing and outputting electric energy. The battery cell may be a secondary battery or a primary battery. The battery cell may be, but is not limited to, a metal battery, a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery. The battery cell may be cylindrical, flat, rectangular, or in other shapes.

[0083] For ease of description, the embodiments of the present application are described using an electrical device as a vehicle as an example.

[0084] In some embodiments, see Figure 1 , Figure 1Schematic diagram of a vehicle 1000 provided for some embodiments of the present application. The above-mentioned battery 100 is disposed inside the vehicle 1000, and the battery 100 can be disposed at the bottom, head, or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000, for example, the battery 100 can be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for the starting, navigation, and working power requirements of the vehicle 1000 during driving.

[0085] In some embodiments, the battery 100 can be used not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0086] In some embodiments, see Figure 2 , Figure 2 The exploded view of the battery 100 provided in some embodiments of the present application. The battery 100 may include a housing 20 and a plurality of battery cells 10. The housing 20 is a structure having a receiving space 201 inside, and the receiving space 201 of the housing 20 is used to receive the battery cells 10.

[0087] The box body 20 may adopt a variety of structures. In some embodiments, the box body 20 may include a first portion 21 and a second portion 22, which cover each other and define the above-mentioned accommodation space 201. Figure 2 , the first part 21 can be a hollow structure with an opening at one end, the second part 22 is a plate-like structure, and the second part 22 covers the open side of the first part 21, so that the first part 21 and the second part 22 jointly define the above-mentioned accommodation space 201. Alternatively, the first part 21 and the second part 22 can both be hollow structures with an opening at one end, and the open side of the first part 21 covers the open side of the second part 22, so that the first part 21 and the second part 22 jointly define the above-mentioned accommodation space 201. Among them, the box body 20 composed of the first part 21 and the second part 22 can be of various shapes, such as a cylinder, a cuboid, etc.

[0088] In some embodiments, see Figure 2, multiple battery cells 10 can be connected in series, in parallel or in a mixed connection to form a whole, and then the whole formed by the multiple battery cells 10 is directly accommodated in the above-mentioned accommodation space 201 of the box body 20. In other embodiments, multiple battery cells 10 can also be connected in series, in parallel or in a mixed connection first, and arranged and fixed to form a battery module, and the battery module is accommodated in the above-mentioned accommodation space 201 of the box body 20. In some other embodiments, multiple battery cells 10 can also be connected in series, in parallel or in a mixed connection first, and arranged and fixed to form multiple battery modules, and multiple battery modules are then connected in series, in parallel or in a mixed connection to form a whole, and accommodated in the above-mentioned accommodation space 201 of the box body 20.

[0089] In some embodiments, the box 20 of the battery 100 can be used as part of the chassis structure of the vehicle 1000. For example, part of the box 20 can become at least a part of the chassis of the vehicle 1000, or part of the box 20 can become at least a part of the cross beam and longitudinal beam of the vehicle 1000.

[0090] In some embodiments, please refer to Figure 3 and Figure 4 , Figure 3 A three-dimensional schematic diagram of a battery cell 10 provided in some embodiments of the present application, Figure 4 for Figure 3 A cross-sectional view along AA. The battery cell 10 may include an electrode assembly 11 .

[0091] The electrode assembly 11 is a component in the battery cell 10 where electrochemical reactions occur. The electrode assembly 11 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and a separator is provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the main body of the electrode assembly 11, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute a pole ear. The pole ear of the positive electrode sheet is the positive pole ear, and the pole ear of the negative electrode sheet is the negative pole ear. The positive pole ear and the negative pole ear can be located together at one end of the main body or respectively at two opposite ends of the main body.

[0092] In the battery cell 10 , the number of the electrode assembly 11 may be one or more.

[0093] In some cases, the electrode assembly 11 may also be referred to as a bare cell, a wound body, a laminated body, etc.

[0094] In some embodiments, the battery cell 10 may further include an electrolyte, which plays a role in conducting ions between the positive electrode plate and the negative electrode plate. The electrolyte involved in the embodiments of the present application may be liquid, gel or solid.

[0095] In some embodiments, please refer to Figure 3 and Figure 4 The battery cell 10 may further include a shell 12 and an end cap 13 , which are components for jointly defining an internal environment of the battery cell 10 , and the internal environment defined by the shell 12 and the end cap 13 is used to accommodate the electrode assembly 11 and the electrolyte.

[0096] The shell 12 and the end cap 13 may be independent components. Specifically, the shell 12 has an opening, and the end cap 13 is disposed at the opening of the shell 12 to define the internal environment of the battery cell 10 together with the shell 12, and to isolate the internal environment of the battery cell 10 from the external environment. Alternatively, the shell 12 and the end cap 13 may also be an integrated structure. Specifically, a common connection surface may be formed between the end cap 13 and the shell 12 before the electrode assembly 11 is placed in the shell. When the electrode assembly 11 needs to be packaged after the electrode assembly 11 is placed in the shell, the end cap 13 covers the shell 12.

[0097] Among them, Figure 3 and Figure 4 As shown, the number of the end cap 13 can be one, and the end cap 13 is disposed at one end of the housing 12. Alternatively, the number of the end cap 13 can also be two, and the two end caps 13 are disposed at opposite ends of the housing 12 respectively.

[0098] The shell 12 may be cylindrical, square, or other shapes, which may be determined according to the specific shape and size of the electrode assembly 11. In addition, the shell 12 and the end cap 13 may be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, or the like.

[0099] Please also read Figures 3 to 13 , and combined with other drawings. Among them, Figure 5 for Figure 4 Enlarged view of point B in the middle. Figure 6 The cross-sectional view of the battery cell 10 provided in some other embodiments of the present application is as follows: Figure 7 for Figure 6 Enlarged view of point C in the middle. Figure 8 The cross-sectional view of the battery cell 10 provided in some embodiments of the present application is as follows: Fig. 9 for Figure 8 Enlarged view of point D in the middle. Fig.10 A cross-sectional view of a battery cell 10 provided in some further embodiments of the present application, Fig.11 for Fig.10 Enlarged view of point E in the middle. Fig.12 A cross-sectional view of a battery cell 10 provided in some other embodiments of the present application, Fig.13 for Fig.12Enlarged view at F in the figure. The battery cell 10 provided in the embodiment of the present application includes an electrode assembly 11, a shell 12 and an end cover 13. The shell 12 includes a shell body 121 and an end structure 122, and the end structure 122 is arranged at the end of the shell body 121 along the first direction Z. At least a portion of the electrode assembly 11 is arranged in the shell body 121, and the outer peripheral wall of the end structure 122 is provided with a groove 1201, and the groove 1201 is arranged along the circumferential direction Y. The groove wall of the groove 1201 constitutes a bending portion 1221, and the bending portion 1221 is bent. The first direction Z is perpendicular to the circumferential direction Y of the groove 1201. At least a portion of the end cover 13 and at least a portion of the electrode assembly 11 are respectively located at opposite ends of the bending portion 1221 along the first direction Z. In addition, the battery cell 10 also includes at least one of the following two schemes:

[0100] First, as Figures 3 to 9 As shown, the battery cell 10 further includes a reinforcement member 14 , at least a portion of which is disposed at the bending portion 1221 .

[0101] Second, if Figures 10 to 13 As shown, the structural strength of the bending portion 1221 is greater than the structural strength of the shell body 121 .

[0102] The shell body 121 refers to the main part of the shell 12, and the shell body 121 can be used to accommodate the electrode assembly 11. The end structure 122 refers to the structure of the end of the shell 12 along the first direction Z, which is a partial structure of the shell 12. The end structure 122 is arranged at the end of the shell 12 along the first direction Z.

[0103] Please continue reading Figures 3 to 13 As shown in the figure, and in combination with other figures. The end cap 13 is arranged at the end of the shell 12, specifically, the end cap 13 is arranged at the end structure 122. Based on this, the shell body 121, the end structure 122 and the end cap 13 are used to jointly define the internal space of the battery cell 10, so that the shell body 121, the end structure 122 and the end cap 13 jointly encapsulate the electrode assembly 11.

[0104] Among them, Figures 3 to 13 As shown, when the number of the end caps 13 is one, the number of the end structure 122 is one, and the end structure 122 is disposed at one end of the shell body 121 along the first direction Z, and the end cap 13 is also disposed at one end of the shell body 12 along the first direction Z, specifically, the end cap 13 is disposed at the end structure 122. When the number of the end caps 13 is two, the number of the end structures 122 is two, and the two end structures 122 are respectively disposed at the opposite ends of the shell body 121 along the first direction Z, and the two end caps 13 are also respectively disposed at the opposite ends of the shell body 12 along the first direction Z, specifically, the two end caps 13 are respectively disposed at the two end structures 122 in a one-to-one correspondence.

[0105] The outer peripheral wall of the end structure 122 is provided with a groove 1201, so that the groove 1201 surrounds the outer peripheral wall of the end structure 122. The surrounding direction of the groove 1201 around the outer peripheral wall of the end structure 122 is the setting direction of the groove 1201, that is, the circumferential direction Y of the groove 1201. Specifically, as Figures 3 to 13 As shown, a groove 1201 is provided on the outer peripheral wall of the end structure 122 in the first direction Z, and the groove 1201 surrounds the outer peripheral wall of the shell 12 . Specifically, the groove 1201 surrounds the outer peripheral wall of the shell 12 .

[0106] The first direction Z refers to the arrangement direction of the shell body 121 and the end structure 122. In some cases, the first direction Z may be a height direction or a length direction of the battery cell 10.

[0107] As an example, see Figures 3 to 13 The battery cell 10 is generally cylindrical. The outer peripheral wall of the end structure 122 around the first direction Z is provided with a groove 1201, which is generally annular and surrounds the outer peripheral wall of the end structure 122 around the first direction Z. The circumferential direction defined by the circle where the groove 1201 is located is the circumferential direction Y of the groove 1201, and the circumferential direction Y of the groove 1201 is perpendicular to the first direction Z. For ease of understanding, Figures 4 to 13 , the radial direction of the groove 1201 is shown, as indicated by the arrow X.

[0108] Please continue reading Figures 3 to 13 The outer peripheral wall of the end structure 122 is concavely arranged to form a groove 1201, and the groove wall of the groove 1201 forms a bent portion 1221. It can be understood that the end structure 122 includes a bent portion 1221, and the bent portion 1221 is bent to form a groove 1201 arranged along the circumferential direction Y on the outer peripheral wall of the end structure 122.

[0109] At least a portion of the electrode assembly 11 is located at one end of the bending portion 1221 along the first direction Z, and at least a portion of the end cover 13 is located at the other end of the bending portion 1221 along the first direction Z, so that at least a portion of the electrode assembly 11 and at least a portion of the end cover 13 are respectively limited to the opposite ends of the bending portion 1221 along the first direction Z.

[0110] The reinforcement member 14 is a component used to strengthen the structural strength of the bending portion 1221. At least part of the reinforcement member 14 is disposed on the bending portion 1221, which can increase the difficulty of relative movement of two walls of the bending portion 1221 opposite to each other along the first direction Z, that is, improve the problem of mutual pulling of the two walls of the bending portion 1221 opposite to each other along the first direction Z, thereby improving the problem of fatigue cracks or even fractures of the bending portion 1221.

[0111] The battery cell 10 provided in the embodiment of the present application is provided with at least one of the following two solutions: the first is to provide at least a portion of the reinforcement 14 at the bending portion 1221; the second is to provide the structural strength of the bending portion 1221 to be greater than the structural strength of the shell body 121, so that the difficulty of the relative movement of the two walls of the bending portion 1221 relative to each other along the first direction Z can be increased, thereby reducing the amplitude of the relative movement of the two walls of the bending portion 1221 relative to each other along the first direction Z, so as to improve the mutual pulling problem of the two walls of the bending portion 1221 relative to each other along the first direction Z, and further improve the problem of fatigue cracks or even fractures of the bending portion 1221. That is, the risk of fatigue cracks or even fractures of the part of the shell 12 at the groove 1201 can be reduced, so as to improve the reliability of the battery cell 10.

[0112] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9 , and in combination with other drawings. The bending portion 1221 includes a first wall 12211, a second wall 12212 and a connecting portion 12213. The first wall 12211 and the second wall 12212 are arranged opposite to each other along the first direction Z, and the connecting portion 12213 connects the first wall 12211 and the second wall 12212. The first wall 12211 and the second wall 12212 are bent relative to the connecting portion 12213. At least one of the connection between the first wall 12211 and the connecting portion 12213, the connection between the second wall 12212 and the connecting portion 12213, and the connecting portion 12213 is provided with a reinforcement member 14.

[0113] The first wall 12211 and the second wall 12212 are two solid walls of the bending portion 1221 that are opposite to each other along the first direction Z. The first wall 12211 , the second wall 12212 and the connecting portion 12213 enclose a groove 1201 .

[0114] One end of the first wall 12211 away from the connecting portion 12213 is connected to the shell body 121. At least part of the electrode assembly 11 is located at one end of the first wall 12211 away from the second wall 12212 along the first direction Z, and at least part of the end cover 13 is located at one end of the second wall 12212 away from the first wall 12211 along the first direction Z, so that at least part of the electrode assembly 11 and at least part of the end cover 13 are respectively limited to the opposite ends of the bending portion 1221 along the first direction Z.

[0115] It should be noted that, in some cases, the first wall 12211 and the second wall 12212 are prone to relative movement, which may cause fatigue cracks or even breakage at the connection between the first wall 12211 and the connecting portion 12213, at the connection between the second wall 12212 and the connecting portion 12213, and at the connecting portion 12213.

[0116] By providing the reinforcing member 14 at least one of the connection between the first wall 12211 and the connection portion 12213, the connection between the second wall 12212 and the connection portion 12213, and the connection portion 12213, the relative movement between the first wall 12211 and the second wall 12212 can be increased, and the problem of fatigue cracks or even fractures of the two opposite walls of the bending portion 1221 along the first direction Z can be improved. That is, the risk of fatigue cracks or even fractures of the part of the housing 12 at the groove 1201 can be reduced, so as to improve the reliability of the battery cell 10.

[0117] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9 , and in combination with other drawings. The connecting portion 12213, the first wall 12211 and the second wall 12212 are respectively provided with reinforcement members 14.

[0118] There are multiple reinforcing members 14, which are spaced apart on the connecting portion 12213, the first wall 12211 and the second wall 12212. Alternatively, one reinforcing member 14 can be disposed on the first wall 12211, the second wall 12212 and the connecting portion 12213 at the same time.

[0119] By providing the reinforcing members 14 on the connecting portion 12213, the first wall 12211 and the second wall 12212, the overall structural strength of the bent portion 1221 can be improved, thereby effectively improving the problem of mutual pulling of the bent portion 1221, and further improving the problem of fatigue cracks or even fractures of the bent portion 1221. That is, the risk of fatigue cracks or even fractures of the housing 12 at the groove 1201 can be reduced, thereby improving the reliability of the battery cell 10.

[0120] In some embodiments, please refer to Figure 4 , Figure 5 , Figure 8 and Fig. 9 , and in combination with other drawings. The reinforcement member 14 includes a first reinforcement member 14a, and at least a portion of the first reinforcement member 14a is disposed on the inner wall of the groove 1201 .

[0121] It can be understood that there is at least one reinforcement member 14. When there is one reinforcement member 14, the reinforcement member 14 is a first reinforcement member 14a; when there are multiple reinforcement members 14, at least one reinforcement member 14 among the multiple reinforcement members 14 is a first reinforcement member 14a.

[0122] In some embodiments, please refer to Figures 6 to 9, and in combination with other drawings. The reinforcement member 14 includes a second reinforcement member 14b, and at least a portion of the second reinforcement member 14b is disposed on the outer wall of the bending portion 1221 away from the groove 1201 .

[0123] It can be understood that the number of the reinforcement member 14 is at least one. When the number of the reinforcement member 14 is one, the reinforcement member 14 is the second reinforcement member 14b; when the number of the reinforcement member 14 is multiple, at least one reinforcement member 14 among the multiple reinforcement members 14 is the second reinforcement member 14b.

[0124] It should be noted that the number of the reinforcement member 14 is at least one. All reinforcement members 14 may be first reinforcement members 14a, such as Figure 4 and Figure 5 As shown, at least part of the first reinforcement member 14a is disposed on the inner wall of the groove 1201; all reinforcement members 14 may also be second reinforcement members 14b, such as Figure 6 and Figure 7 As shown, at least part of the second reinforcement member 14b is disposed on the outer wall of the bending portion 1221 away from the groove 1201; when there are multiple reinforcement members 14, part of the reinforcement members 14 can also be the first reinforcement member 14a, and part of the second reinforcement member 14b can be the second reinforcement member 14b, such as Figure 8 and Fig. 9 As shown, at least a portion of the first reinforcement member 14 a is disposed on the inner wall of the groove 1201 , and at least a portion of the second reinforcement member 14 b is disposed on the outer wall of the bending portion 1221 away from the groove 1201 .

[0125] Such an arrangement makes it possible to flexibly arrange the reinforcement member 14 on the bending portion 1221 .

[0126] It should be supplemented here that at least one of the connection between the first wall 12211 and the connection part 12213, the connection between the second wall 12212 and the connection part 12213, and the connection part 12213 may be provided with a first reinforcement 14a, and at least one of the connection between the first wall 12211 and the connection part 12213, the connection between the second wall 12212 and the connection part 12213, and the connection part 12213 may also be provided with a second reinforcement 14b.

[0127] As an example, Figure 8 and Fig. 9 As shown, the first reinforcement member 14a is disposed on the connecting portion 12213 , the first wall 12211 and the second wall 12212 , and the second reinforcement member 14b is also disposed on the connecting portion 12213 , the first wall 12211 and the second wall 12212 .

[0128] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9The end structure 122 further includes a third wall 1222, which is connected to the end of the bending portion 1221 away from the shell body 121 along the first direction Z, at least part of the third wall 1222 is arranged around at least part of the outer periphery of the end cover 13, and part of the reinforcement member 14 is arranged on the third wall 1222.

[0129] The third wall 1222 refers to a solid wall of the end structure 122 .

[0130] Specifically, the third wall 1222 and the shell body 121 are spaced apart from each other along the first direction Z. The first wall 12211 is connected to the shell body 121 , and the second wall 12212 is connected to the third wall 1222 .

[0131] By providing the third wall 1222, the end cover 13 can be provided on the third wall 1222, so that the end cover 13 can be provided on the shell 12. In addition, by providing the reinforcement member 14 on the third wall 1222, the bending portion 1221 of the end structure 122 and the third wall 1222 are both provided with the reinforcement member 14, so that the overall structural strength of the end structure 122 can be improved, so that the problem of the two walls of the bending portion 1221 that are opposite to each other along the first direction Z can be improved, and further the problem of fatigue cracks or even fractures of the bending portion 1221 can be improved.

[0132] In some embodiments, please refer to Figure 5 and Fig. 9 , and in combination with other drawings. The reinforcement member 14 includes a first reinforcement member 14a, and a portion of the first reinforcement member 14a is disposed on the outer wall of the third wall 1222.

[0133] It can be understood that there is at least one reinforcement member 14. When there is one reinforcement member 14, the reinforcement member 14 is a first reinforcement member 14a; when there are multiple reinforcement members 14, at least one reinforcement member 14 among the multiple reinforcement members 14 is a first reinforcement member 14a.

[0134] In some embodiments, please refer to Figure 7 and Fig. 9 , and in combination with other drawings. The reinforcement member 14 includes a second reinforcement member 14 b , and a portion of the second reinforcement member 14 b is disposed on the inner wall of the third wall 1222 .

[0135] It can be understood that the number of the reinforcement member 14 is at least one. When the number of the reinforcement member 14 is one, the reinforcement member 14 is the second reinforcement member 14b; when the number of the reinforcement member 14 is multiple, at least one reinforcement member 14 among the multiple reinforcement members 14 is the second reinforcement member 14b.

[0136] It should be noted that the number of the reinforcement member 14 is at least one. All reinforcement members 14 may be first reinforcement members 14a, such as Figure 4 and Figure 5 As shown, part of the first reinforcement member 14a is disposed on the outer wall of the third wall 1222; all reinforcement members 14 may also be second reinforcement members 14b, such as Figure 6 and Figure 7 As shown, part of the second reinforcement member 14b is disposed on the inner wall of the third wall 1222; when the number of reinforcement members 14 is multiple, part of the reinforcement members 14 can also be the first reinforcement member 14a, and part of the second reinforcement member 14b can be the second reinforcement member 14b, such as Figure 8 and Fig. 9 As shown, part of the first reinforcement member 14 a is disposed on the outer wall of the third wall 1222 , and part of the second reinforcement member 14 b is disposed on the inner wall of the third wall 1222 .

[0137] It should be further explained that when the battery cell 10 includes the first reinforcement 14a, the first reinforcement 14a may be disposed only on the inner wall of the groove 1201, or only on the outer wall of the third wall 1222, or partially on the inner wall of the groove 1201 and partially on the outer wall of the third wall 1222. When the battery cell 10 includes the second reinforcement 14b, the second reinforcement 14b may be disposed only on the outer wall of the groove 1201, or only on the inner wall of the third wall 1222, or partially on the outer wall of the groove 1201 and partially on the inner wall of the third wall 1222.

[0138] Such an arrangement makes it very flexible to arrange the reinforcement member 14 on the third wall 1222 .

[0139] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9 , and in combination with other drawings. The battery cell 10 includes a first reinforcement member 14 a , and the first reinforcement member 14 a is disposed on the inner wall of the groove 1201 and the outer wall of the third wall 1222 .

[0140] By adopting the above technical solution, the first reinforcement member 14a can be firstly arranged on the outer peripheral wall of the shell 12, and then the shell 12 is processed with the groove 1201, so that the end structure 122 is formed with the groove 1201. At this time, the first reinforcement member 14a can be directly arranged on the inner wall of the groove 1201 and the outer wall of the third wall 1222. In this way, there is no need to strictly position the first reinforcement member 14a, so that the setting operation of the first reinforcement member 14a on the shell 12 is very simple, and thus the processing operation of the battery cell 10 is very simple.

[0141] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9, and in combination with other drawings. The battery cell 10 includes a second reinforcement member 14 b , and the second reinforcement member 14 b is disposed on the outer wall of the groove 1201 and the inner wall of the third wall 1222 .

[0142] By adopting the above technical solution, the second reinforcement member 14b can be firstly arranged on the inner peripheral wall of the shell 12, and then the shell 12 is processed with the groove 1201, so that the end structure 122 is formed with the groove 1201. At this time, the second reinforcement member 14b can be directly arranged on the outer wall of the groove 1201 and the inner wall of the third wall 1222. In this way, there is no need to strictly position the second reinforcement member 14b, so that the setting operation of the second reinforcement member 14b on the shell 12 is very simple, and thus the processing operation of the battery cell 10 is very simple.

[0143] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9 , and in combination with other drawings. The reinforcement member 14 satisfies the following relationship:

[0144] 0<T2 / T1≤5;

[0145] Wherein, T1 is the wall thickness of the shell body 121 , and T2 is the wall thickness of the reinforcement member 14 .

[0146] Among them, T2 / T1 can specifically be 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, etc.

[0147] It can be understood that when the reinforcement member 14 includes the first reinforcement member 14a, the wall thickness of the first reinforcement member 14a can be T2. When the reinforcement member 14 includes the second reinforcement member 14b, the wall thickness of the second reinforcement member 14b can be T2.

[0148] By adopting the above technical solution, the wall thickness of the reinforcement 14 can be within a reasonable range, so that the reinforcement 14 has a greater structural strength to improve the structural strength of the bending portion 1221, and will not occupy too much space in the battery cell 10, thereby allowing the battery cell 10 to have a better energy density.

[0149] In some embodiments, 0.2≤T2 / T1<2.

[0150] Among them, T2 / T1 can specifically be 0.2, 0.5, 0.8, 1, 1.2, 1.5, 1.7, 1.9, etc.

[0151] Such a configuration allows the reinforcement member 14 to have a larger wall thickness and greater structural strength, thereby effectively improving the structural strength of the bent portion 1221, improving the problem of the bent portions 1221 pulling each other, and further improving the problem of fatigue cracks or even fractures of the bent portions 1221. In addition, the wall thickness of the reinforcement member 14 is within a reasonable range and does not occupy too much space in the battery cell 10, thereby allowing the battery cell 10 to have a better energy density.

[0152] In some embodiments, please refer to Figures 10 to 13 , and combined with other drawings. The structural strength of the bending portion 1221 is greater than the structural strength of the shell body 121, and at least one of the following two solutions can be adopted:

[0153] First, the wall thickness of at least a portion of the bending portion 1221 is greater than the wall thickness of the shell body 121 .

[0154] Based on this, the bending portion 1221 has a greater wall thickness than the shell body 121 to have a greater structural strength. In this way, the difficulty of relative movement of the two walls of the bending portion 1221 along the first direction Z can be increased, that is, the pulling problem of the bending portion 1221 is improved, and then the problem of fatigue cracks or even fractures of the bending portion 1221 is improved.

[0155] The second type is that the material of at least a portion of the bending portion 1221 is different from the material of the shell body.

[0156] Based on this, the structural strength of the material of at least part of the bending portion 1221 is greater than the structural strength of the material of the shell body, so that the structural strength of the bending portion 1221 is greater than the structural strength of the shell body 121. For example, the shell body 121 is made of aluminum, and the material of the bending portion 1221 is steel. In this way, the difficulty of relative movement of the two walls of the bending portion 1221 relative to each other along the first direction Z can be increased, that is, the problem of mutual pulling of the two walls of the bending portion 1221 relative to each other along the first direction Z can be improved, thereby improving the problem of fatigue cracks or even fractures of the bending portion 1221.

[0157] By adopting at least one of the two solutions that the wall thickness of at least part of the bending portion is greater than the wall thickness of the shell body, and the material of at least part of the bending portion is different from the material of the shell body, the structural strength of the bending portion can be made greater than the structural strength of the shell body. In this way, the difficulty of relative movement of the two walls of the bending portion relative to each other along the first direction can be increased to reduce the amplitude of relative movement, thereby improving the problem of the two walls of the bending portion relative to each other along the first direction pulling each other, reducing the risk of fatigue cracks or even fractures in the part of the shell at the groove, and improving the reliability of the battery cell.

[0158] In some embodiments, please refer to Figure 5 , Figure 7and Fig. 9 , and in combination with other drawings. The bending portion 1221 satisfies the following relationship:

[0159] 0<T3 / T1≤5;

[0160] Wherein, T1 is the wall thickness of the shell body 121 , and T3 is the wall thickness of the bending portion 1221 .

[0161] Among them, T3 / T1 can specifically be 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, etc.

[0162] It can be understood that T3 can be greater than T1, or less than or equal to T1.

[0163] By adopting the above technical solution, the wall thickness of the bending portion 1221 can be within a reasonable range, so that the bending portion 1221 will not occupy too much space of the battery cell 10 while having a certain structural strength, thereby allowing the battery cell 10 to have a better energy density.

[0164] In some embodiments, 0<T3 / T1≤2.

[0165] Among them, T3 / T1 can specifically be 0.5, 0.8, 1, 1.2, 1.5, 1.7, 1.9, 2, etc.

[0166] Such an arrangement allows the wall thickness of the bending portion 1221 to be within a reasonable range, so that the bending portion 1221 will not occupy too much space of the battery cell 10 while having a certain structural strength, thereby allowing the battery cell 10 to have a better energy density.

[0167] In some embodiments, please refer to Figure 5 , Figure 7 and Fig. 9 , and in combination with other drawings. 1.1≤T3 / T1.

[0168] Among them, T3 / T1 can specifically be 1.1, 1.3, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, etc.

[0169] By configuring in this way, the wall thickness of the bending portion 1221 is greater than the wall thickness of the shell body 121. Therefore, compared with the shell body 121, the structural strength of the bending portion 1221 can be greater, which can increase the difficulty of relative movement of the two walls of the bending portion 1221 opposite to each other along the first direction Z, that is, improve the pulling problem of the two walls of the bending portion 1221 opposite to each other along the first direction Z, and further improve the problem of fatigue cracks or even breakage of the bending portion 1221.

[0170] It should be noted here that, in at least one of the following two cases, that is, the battery cell 10 further includes a reinforcement 14 and the material of the bending portion 1221 is different from the material of the shell body 121, the wall thickness of the bending portion 1221 may be greater than the wall thickness of the shell body 121, or may be less than the wall thickness of the shell body 121, or may even be equal to the wall thickness of the shell body 121.

[0171] In some embodiments, see Fig.11 , and in combination with other drawings. The end structure 122 further includes a third wall 1222, the third wall 1222 is connected to the end of the bending portion 1221 away from the shell body 121 along the first direction Z, and at least part of the third wall 1222 is arranged around at least part of the outer periphery of the end cover 13. In addition, the wall thickness of the bending portion 1221 and the wall thickness of the third wall 1222 are both greater than the wall thickness of the shell body 121.

[0172] By adopting the above technical solution, when designing the shell 12, the wall thickness of the end of the shell 12 along the first direction Z (that is, the end structure 122) can be increased, and then the shell 12 is processed with the groove 1201. After the groove 1201 is formed, the part with increased wall thickness can constitute the bending part 1221 and the third wall 1222, so that the wall thickness of the bending part 1221 and the wall thickness of the third wall 1222 are both greater than the wall thickness of the shell body 121, thereby improving the pulling problem of the two opposite walls of the bending part 1221 along the first direction Z, and further improving the problem of fatigue cracks or even fractures of the bending part 1221. In this way, compared with the solution in which only the wall thickness of the bending part 1221 is greater than the wall thickness of the shell body 121, there is no need to strictly position the part with increased wall thickness, that is, there is no need to divide the bending part 1221 in advance, which can simplify the processing operation of increasing the wall thickness of the bending part 1221.

[0173] In some embodiments, see Fig.13 , and in combination with other drawings. The end structure 122 further includes a third wall 1222, the third wall 1222 is connected to the end of the bending portion 1221 away from the shell body 121 along the first direction Z, and at least part of the third wall 1222 is disposed around at least part of the outer periphery of the end cover 13. In addition, the material of the bending portion 1221 and the material of the third wall 1222 are different from the material of the shell body 121.

[0174] By setting the material of the bending portion 1221 and the material of the third wall 1222 to be different from the material of the shell body 121, the bending portion 1221 and the third wall 1222 can be made of a material with a greater structural strength than the shell body 121, so that the structural strength of the bending portion 1221 and the structural strength of the third wall 1222 are respectively greater than the structural strength of the shell body 121. In this way, the pulling problem of the two opposite walls of the bending portion 1221 along the first direction Z can be improved, and then the problem of fatigue cracks or even fractures of the bending portion 1221 can be improved.

[0175] With such arrangement, the material of the bending portion 1221 and the material of the third wall 1222 can be designed to be the same and greater than the material of the shell body 121. In this way, when designing the shell 12, the material of the end portion of the shell 12 along the first direction Z (that is, the end structure 122) can be designed to be different from the shell body 121, and then the shell 12 is processed with the groove 1201. After the groove 1201 is formed, the end portion of the shell 12 along the first direction Z can constitute the bending portion 1221 and the third wall 1222, so that the material of the bending portion 1221 and the material of the third wall 1222 are different from the material of the shell body 121, and the structural strength of the bending portion 1221 and the structural strength of the third wall 1222 can be respectively greater than the material of the shell body 121. Thus, compared with the solution where only the structural strength of the bending portion 1221 is greater than the structural strength of the shell body 121 , there is no need to strictly position the portion with increased structural strength, that is, there is no need to divide the bending portion 1221 in advance, which can simplify the processing operation of the battery cell 10 .

[0176] See also Figure 2 , and in combination with other drawings. The battery 100 provided in the embodiment of the present application includes a battery cell 10. The battery cell 10 in this embodiment is the same as the battery cell 10 in the previous embodiment. For details, please refer to the relevant description of the battery cell 10 in the previous embodiment, which will not be repeated here.

[0177] The battery 100 provided in the embodiment of the present application, by adopting the battery cell 10 involved above, can reduce the risk of fatigue cracks or even breakage of the portion of the shell 12 at the groove 1201, thereby improving the reliability of the battery cell 10 and further improving the reliability of the battery 100.

[0178] See also Figure 1 The electric device provided in the embodiment of the present application includes a battery cell 10 or a battery 100. The battery cell 10 and the battery 100 in the present embodiment are the same as the battery cell 10 and the battery 100 in the previous embodiment. For details, please refer to the relevant description of the battery cell 10 and the battery 100 in the previous embodiment, which will not be repeated here.

[0179] The electrical device provided in the embodiment of the present application, by adopting the battery cell 10 or battery 100 involved above, can reduce the risk of fatigue cracks or even breakage in the portion of the shell 12 at the groove 1201, thereby improving the reliability of the battery cell 10 and further improving the reliability of the electrical device.

[0180] As one of the embodiments of this application, Figures 3 to 5As shown, the battery cell 10 includes an electrode assembly 11, a shell 12, an end cover 13 and a reinforcement member 14. The shell 12 includes a shell body 121 and an end structure 122, and the end structure 122 is arranged at the end of the shell body 121 along the first direction Z. At least part of the electrode assembly 11 is arranged in the shell body 121. The outer peripheral wall of the end structure 122 is provided with a groove 1201, and the groove wall of the groove 1201 constitutes a bending portion 1221. The end structure 122 also includes a third wall 1222. The shell body 121 is connected to one end of the bending portion 1221 along the first direction Z, and the third wall 1222 is connected to one end of the bending portion 1221 away from the shell body 121 along the first direction Z. At least part of the third wall 1222 is arranged around at least part of the outer periphery of the end cover 13, and the end cover 13 is arranged on the third wall 1222. In the first direction Z, at least part of the electrode assembly 11 and at least part of the end cap 13 are respectively located at opposite ends of the bending portion 1221. Part of the reinforcement 14 is disposed at the bending portion 1221, and specifically at the inner wall of the groove 1201. Part of the reinforcement 14 is disposed at the outer wall of the third wall 1222.

[0181] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: Electrode assembly; A shell, comprising a shell body and an end structure arranged at an end of the shell body along a first direction, wherein at least a portion of the electrode assembly is arranged in the shell body, an outer peripheral wall of the end structure is provided with a groove arranged along a circumferential direction, a groove wall of the groove constitutes a bent portion arranged in a bent direction, and the first direction is perpendicular to the circumferential direction of the groove; an end cap, at least a portion of the end cap and at least a portion of the electrode assembly being respectively disposed at two opposite ends of the bent portion along the first direction; Wherein, the battery cell further includes a reinforcement member at least partially disposed on the bent portion, and / or the structural strength of the bent portion is greater than the structural strength of the shell body.

2. The battery cell according to claim 1, characterized in that: The bending portion includes a first wall and a second wall opposite to each other along the first direction, and a connecting portion connecting the first wall and the second wall; the first wall and the second wall are respectively bent relative to the connecting portion; The reinforcing member is provided at least one of a connection point between the first wall and the connection portion, a connection point between the second wall and the connection portion, and the connection portion.

3. The battery cell according to claim 2, characterized in that: The connecting portion, the first wall and the second wall are respectively provided with the reinforcing member.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The reinforcement member includes a first reinforcement member, at least a portion of which is disposed on an inner wall of the groove; And / or, the reinforcement member includes a second reinforcement member, at least a portion of which is disposed on an outer wall of the bending portion away from the groove.

5. The battery cell according to any one of claims 1 to 4, characterized in that: The end structure also includes a third wall, which is connected to the end of the bending portion away from the shell body along the first direction and at least partially surrounds at least a portion of the outer circumference of the end cover, and part of the reinforcement is arranged on the third wall.

6. The battery cell according to claim 5, characterized in that: The reinforcement member includes a first reinforcement member, a portion of which is disposed on the outer wall of the third wall; And / or, the reinforcement member includes a second reinforcement member, and a portion of the second reinforcement member is arranged on the inner wall of the third wall.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The reinforcement member satisfies the following relationship: 0<T2 / T1≤5; Wherein, T1 is the wall thickness of the shell body, and T2 is the wall thickness of the reinforcement.

8. The battery cell according to claim 7, characterized in that: 0.2≤T2 / T1<2.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The wall thickness of at least a portion of the bent portion is greater than the wall thickness of the shell body, and / or the material of at least a portion of the bent portion is different from that of the shell body.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The bending portion satisfies the following relationship: 0<T3 / T1≤5; Wherein, T1 is the wall thickness of the shell body, and T3 is the wall thickness of the bending portion.

11. The battery cell according to claim 10, characterized in that: 0<T3 / T1≤2.

12. The battery cell according to claim 10 or 11, characterized in that: 1.1≤T3 / T1.

13. The battery cell according to any one of claims 1 to 12, characterized in that: The end structure also includes a third wall, which is connected to the end of the bending portion away from the shell body along the first direction and at least partially surrounds at least part of the outer circumference of the end cover. The wall thickness of the bending portion and the wall thickness of the third wall are both greater than the wall thickness of the shell body.

14. The battery cell according to any one of claims 1 to 13, characterized in that: The end structure also includes a third wall, which is connected to the end of the bending portion away from the shell body along the first direction and at least partially surrounds at least part of the outer circumference of the end cover. The material of the bending portion and the material of the third wall are different from the material of the shell body.

15. A battery, characterized in that: Comprising a battery cell according to any one of claims 1-14.

16. An electrical device, characterized in that: Comprising a battery cell according to any one of claims 1 to 14; or comprising a battery according to claim 15.

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