Battery cell, battery and electric device

Abstract

The invention discloses a battery monomer, a battery and an electric device. A battery cell includes a case (20), a first electrode terminal (30), an electrode assembly (10), and a first insulating member (50). The shell (20) comprises a first wall (20b) and a second wall (20c) surrounding the periphery of the first wall (20b). The first electrode terminal (30) is provided on the first wall (20b). The electrode assembly (10) includes an electrode body (11) and a first tab (12) extending from an end of the electrode body (11) facing the first wall (20b) and electrically connected to the first electrode terminal (30). The first insulating component (50) comprises a first insulating main body (51) and a first limiting part (52), at least part of the first insulating main body (51) is located between the first wall (20b) and the electrode main body (11), the first limiting part (52) protrudes out of the first insulating main body (51), and at least part of the first limiting part (52) is located between the second wall (20c) and the electrode main body (11).

Description

Battery cells, batteries, and electrical devices Technical Field

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

[0002] Battery cells are widely used in electronic devices such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric boats, electric toy cars, electric toy boats, electric toy airplanes and power tools, etc.

[0003] How to improve the reliability of battery cells is a research direction in battery technology.

[0004] Summary of the Invention

[0005] The present application provides a battery cell, a battery, and an electrical device, which can improve reliability.

[0006] In a first aspect, an embodiment of the present application provides a battery cell comprising a housing, a first electrode terminal, an electrode assembly, and a first insulating member. The housing comprises a first wall and a second wall surrounding the outer periphery of the first wall. The first electrode terminal is disposed on the first wall. The electrode assembly comprises an electrode body and a first tab, the first tab extending from one end of the electrode body facing the first wall and electrically connected to the first electrode terminal. The first insulating member comprises a first insulating body and a first limiting portion, at least a portion of the first insulating body being located between the first wall and the electrode body, the first limiting portion protruding from the first insulating body, and at least a portion of the first limiting portion being located between the second wall and the electrode body.

[0007] When the battery cell is subjected to external impact, the first insulating body and the first limiting portion can limit the vibration of the electrode body in multiple directions, thereby reducing the tension on the first tab, reducing the risk of the first tab tearing, and improving the reliability of the battery cell. Furthermore, the first insulating body and the first limiting portion also provide insulation, reducing the risk of the first wall and the second wall connecting the positive and negative poles of the electrode body, thereby improving reliability.

[0008] In some embodiments, the battery cell further includes a pressure relief mechanism disposed on the second wall; along the thickness direction of the pressure relief mechanism, the pressure relief mechanism does not overlap with the first stopper. In the event of thermal runaway in the battery cell, high-temperature substances released from the electrode body can be discharged through the pressure relief channel formed by the pressure relief mechanism. The first stopper does not overlap with the pressure relief mechanism, thereby reducing the first stopper's barrier to high-temperature substances and improving pressure relief efficiency.

[0009] In some embodiments, the thickness of the first limiting portion is 0.1 mm to 1.5 mm. Limiting the thickness of the first limiting portion to greater than or equal to 0.1 mm increases the strength of the first limiting portion, reduces deformation of the first limiting portion under impact with the electrode body, increases the gap between the electrode body and the second wall, and improves the reliability of the battery cell. Limiting the thickness of the first limiting portion to less than or equal to 1.5 mm reduces the volume and weight of the first limiting portion, improves space utilization, and increases the energy density of the battery cell.

[0010] In some embodiments, the first insulating body and the first limiting portion are formed integrally to improve the connection strength between the first insulating body and the first limiting portion and to simplify the assembly process of the first insulating member.

[0011] In some embodiments, the first wall and the electrode body are arranged along a first direction. The electrode body has a dimension L1 along the first direction, and the portion of the first stop located between the second wall and the electrode body has a dimension L2 along the first direction, where L2 is smaller than L1. The first stop can have a smaller dimension than the electrode body in the first direction to save space and improve energy density.

[0012] In some embodiments, the battery cell further includes a first connector connecting the electrode body and the first stopper. The first connector limits relative movement between the first stopper and the electrode body. When the battery cell is subjected to an external impact, the first connector can restrain the electrode body, reduce the force applied to the first tab, and reduce the risk of tearing the first tab.

[0013] In some embodiments, the first connecting member includes a first connecting portion connected to the electrode body and a second connecting portion connected to the first limiting portion, and the first connecting member is used to limit the relative movement of the first limiting portion and the electrode body.

[0014] In some embodiments, the first connecting member comprises an adhesive tape, which is small in size and easy to assemble.

[0015] In some embodiments, the housing includes a third wall, the first wall and the third wall are arranged opposite each other along a first direction, and the second wall connects the first wall and the third wall. The battery cell also includes a second electrode terminal disposed on the third wall, and the electrode assembly includes a second electrode tab, which extends from an end of the electrode body facing the third wall and is electrically connected to the second electrode terminal. The battery cell also includes a second insulating member, the second insulating member including a second insulating body and a second limiting portion, at least a portion of the second insulating body is located between the third wall and the electrode body, the second limiting portion protrudes from the second insulating body, and at least a portion of the second limiting portion is located between the second wall and the electrode body.

[0016] When the battery cell is subjected to external impact, the second insulating body and the second limiting portion can limit the vibration of the electrode body in multiple directions, thereby reducing the tension on the second tab, reducing the risk of the second tab tearing, and improving the reliability of the battery cell. In addition, the second insulating body and the second limiting portion also provide insulation, reducing the risk of the third wall and the second wall connecting the positive and negative poles of the electrode body, thereby improving reliability.

[0017] In some embodiments, the second insulating body is provided with a through hole, through which the second tab passes and is connected to the second electrode terminal. The second insulating body can support the second tab, reducing the risk of the second tab being inserted backwards into the electrode body and improving reliability.

[0018] In some embodiments, the battery cell further includes a third insulating member, at least partially located between the third wall and the second insulating body, connecting the third wall and the second insulating body. The provision of the third insulating member further improves insulation and reliability. The third insulating member secures the second insulating member to the third wall, thereby enhancing its stability.

[0019] In some embodiments, the first limiting portion and the second limiting portion are spaced apart along the first direction to reduce the risk of interference between the first limiting portion and the second limiting portion.

[0020] In some embodiments, in the first direction, the size of the electrode body is L1, the portion of the first limiter located between the electrode body and the second wall is L2, and the portion of the second limiter located between the electrode body and the second wall is L3; wherein 0.2≤(L2+L3) / L1≤0.8. (L2+L3) / L1 is limited to greater than or equal to 0.2 to increase the area where the electrode body is constrained, reduce the vibration amplitude of the electrode body, reduce the risk of tab tearing, and improve the reliability of the battery cell. (L2+L3) / L1 is limited to less than or equal to 0.8 to reduce the space occupied by the first and second limiters and improve the energy density of the battery cell.

[0021] In some embodiments, the housing includes a shell, a first end cap, and a second end cap. The shell has a first opening and a second opening at both ends along a first direction. The first end cap is connected to the shell and covers the first opening, and the second end cap is connected to the shell and covers the second opening. The first end cap is a first wall, the shell is a second wall, and the second end cap is a third wall.

[0022] In some embodiments, the housing includes a shell and a first end cap, wherein one end of the shell has a first opening, and the first end cap is connected to the shell and covers the first opening. The first end cap is a first wall.

[0023] In some embodiments, the first insulating member includes two first limiting portions, each located on opposite sides of the electrode body. The two first limiting portions can limit the electrode body from two sides to reduce movement of the electrode body within the housing and reduce the risk of tearing of the first tab.

[0024] In some embodiments, the first wall is located on one side of the electrode body along the first direction, and the first stop is located on one side of the electrode body along the second direction. In the third direction, both ends of the first stop do not extend beyond the electrode body. The first, second, and third directions are perpendicular to each other. In the third direction, the first stop and the electrode body share space, thereby improving space utilization and increasing energy density.

[0025] In some embodiments, the first wall is located on one side of the electrode body along the first direction. The electrode body includes two first outer surfaces disposed opposite each other along the second direction and two second outer surfaces disposed opposite each other along the third direction. The area of ​​the first outer surface is smaller than the area of ​​the second outer surface. The first direction, the second direction, and the third direction are perpendicular to each other. The first stop is located between the first outer surface and the second wall.

[0026] During the charging process of a battery cell, the electrode body expands. When the electrode body expands, the deformation of the first outer surface is small. Positioning the first limiting portion between the first outer surface and the second wall can reduce the expansion force on the first limiting portion and reduce its deformation. When the electrode body expands, the second outer surface deforms significantly. Positioning the first limiting portion away from the second outer surface can reduce the risk of the first limiting portion squeezing the second outer surface, reduce stress concentration on the second outer surface, reduce the risk of electrode fracture and ion precipitation, and improve the reliability of the battery cell.

[0027] In some embodiments, the first wall is located on one side of the electrode body along the first direction. The second wall includes two first sub-walls, two second sub-walls and four bent walls, the two first sub-walls are arranged oppositely along the second direction, the two second sub-walls are arranged oppositely along the third direction, each bent wall connects the first sub-wall and the second sub-wall, and the first direction, the second direction and the third direction are perpendicular to each other. In the second direction, the first limiting portion is located between the first sub-wall and the electrode body, and the first limiting portion does not overlap with the bent wall. The bent wall can disperse stress and reduce the risk of shell rupture. The first limiting portion does not overlap with the bent wall, thereby reducing the risk of the first limiting portion deforming when squeezed by the electrode body.

[0028] In some embodiments, the area of ​​the second sub-wall is larger than the area of ​​the first sub-wall. In some embodiments, the area of ​​the second sub-wall is larger than the area of ​​the first end cap, and the area of ​​the second sub-wall is larger than the area of ​​the second end cap.

[0029] In some embodiments, the electrode body includes a straight region and a bent region, with the bent region located on one side of the straight region and the first tab connected to the straight region. A first stopper is located on the side of the bent region away from the straight region. The first stopper can constrain the bent region, reducing deformation of the bent region during the charge and discharge processes of the battery cell.

[0030] In some embodiments, a first recess is provided on the side of the first stopper facing the bending zone, and a portion of the bending zone is accommodated in the first recess. The provision of the first recess can increase the area of ​​the portion of the first stopper that can contact the bending zone, thereby enabling the first stopper to more effectively restrain the bending zone and reduce deformation of the bending zone.

[0031] In some embodiments, the first limiting portion surrounds the electrode body, and can limit the electrode body from the periphery, thereby reducing vibration of the electrode body and improving the reliability of the battery cell.

[0032] In a second aspect, an embodiment of the present application provides a battery comprising a plurality of battery cells provided by any embodiment of the first aspect.

[0033] In a third aspect, an embodiment of the present application provides an electrical device, which includes a battery provided by any embodiment of the second aspect, and the battery is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. 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 the drawings without creative work.

[0035] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0036] FIG2 is a schematic diagram of an explosion of a battery provided in some embodiments of the present application;

[0037] FIG3 is a schematic diagram of the three-dimensional structure of a battery cell provided in some embodiments of the present application;

[0038] FIG4 is a schematic cross-sectional view of a battery cell provided in some embodiments of the present application;

[0039] FIG5 is a schematic diagram of an electrode assembly of a battery cell provided in some embodiments of the present application;

[0040] FIG6 is a schematic cross-sectional view taken along the AA direction in FIG5 ;

[0041] FIG7 is a schematic structural diagram of a first end cover assembly of a battery cell provided in some embodiments of the present application;

[0042] FIG8 is a schematic side view of a partial structure of a battery cell provided in some embodiments of the present application;

[0043] FIG9 is an enlarged schematic diagram of FIG4 at the circle B;

[0044] FIG10 is an enlarged schematic diagram of the circle C in FIG4;

[0045] FIG11 is an enlarged schematic diagram of the circle D in FIG4 ;

[0046] FIG12 is a schematic structural diagram of a second insulating member provided in some embodiments of the present application;

[0047] FIG13 is another schematic cross-sectional view of a battery cell provided by some embodiments of the present application;

[0048] FIG14 is an enlarged schematic diagram of the circle frame of FIG13;

[0049] FIG15 is a schematic cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0050] FIG16 is a schematic cross-sectional view of a battery cell provided in some other embodiments of the present application.

[0051] Description of the accompanying drawings: 1. vehicle; 2. battery; 3. controller; 4. motor; 5. housing; 5a. first housing portion; 5b. second housing portion; 5c. storage space; 6. battery cell; 10. electrode assembly; 10a. positive electrode sheet; 10b. negative electrode sheet; 10c. separator; 11. electrode body; 111. first outer surface; 112. second outer surface; 11a. straight region; 11b. bending region; 12. first electrode tab; 13. second electrode tab; 20. housing; 20a. first wall; 20b. second wall; 20c. third wall; 21. housing; 211. first opening; 212. second opening; 213. first sub-wall; 214. second sub-wall; 215. bending wall; 22. first end cap; 23. second end cap; 30. first electrode terminal; 40. second electrode terminal; 50. First insulating member; 51. First insulating body; 52. First limiting portion; 521. First recess; 60. Pressure relief mechanism; 70. First connecting piece; 701. First connecting portion; 702. Second connecting portion; 71. Second connecting piece; 80. Second insulating member; 81. Second insulating body; 811. Through hole; 82. Second limiting portion; 90. Third insulating member; X, second direction; Y, third direction; Z, first direction. DETAILED DESCRIPTION

[0052] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0053] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0054] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0055] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0056] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0057] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0058] The term "plurality" used in this application refers to two or more (including two).

[0059] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0060] Battery cells may include but are not limited to lithium-ion battery cells, sodium-ion battery cells, sodium-lithium-ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium-sulfur battery cells, magnesium-ion battery cells, nickel-hydrogen battery cells, nickel-cadmium battery cells, lead-acid battery cells, etc.

[0061] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc. There is no special limitation in this application.

[0062] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0063] 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.

[0064] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are housed in the case.

[0065] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0066] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0067] A battery cell generally consists of an electrode assembly, a casing, and electrode terminals. The electrode assembly is housed within the casing, and the electrode terminals are located within the casing. The electrode assembly includes tabs, which are electrically connected to the electrode terminals. The electrode terminals can be used to electrically connect the electrode assembly to circuits outside the battery cell to enable charging or discharging of the battery cell.

[0068] When a battery cell is subjected to external impact, the electrode assembly may vibrate inside the casing, thereby pulling the tabs, causing the risk of tab tearing and affecting the reliability of the battery cell.

[0069] In view of this, an embodiment of the present application provides a technical solution, which limits the electrode assembly by arranging an insulating component in the shell, thereby reducing the vibration of the electrode assembly when the battery cell is subjected to external impact, reducing the risk of tab tearing, and improving the reliability of the battery cell.

[0070] The technical solutions described in the embodiments of the present application are applicable to electrical devices using batteries.

[0071] Electrical devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may include fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles may include pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0072] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0073] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application.

[0074] As shown in FIG1 , a battery 2 is provided inside the vehicle 1. The battery 2 may be provided at the bottom, head, or tail of the vehicle 1. The battery 2 may be used to power the vehicle 1. For example, the battery 2 may serve as an operating power source for the vehicle 1.

[0075] The vehicle 1 may further include a controller 3 and a motor 4 . The controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of the vehicle 1 during startup, navigation, and driving.

[0076] In some embodiments of the present application, the battery 2 can not only serve as the operating power source of the vehicle 1, but also serve as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0077] FIG2 is a schematic diagram of an explosion of a battery provided in some embodiments of the present application.

[0078] As shown in FIG. 2 , the battery 2 includes a housing 5 and a battery cell 6 , and the battery cell 6 is accommodated in the housing 5 .

[0079] The housing 5 is used to accommodate the battery cells 6 and can have various structures. In some embodiments, the housing 5 can include a first housing portion 5a and a second housing portion 5b. The first housing portion 5a and the second housing portion 5b overlap each other and together define a storage space 5c for accommodating the battery cells 6. The second housing portion 5b can be a hollow structure with one end open. The first housing portion 5a is a plate-like structure, and the first housing portion 5a overlaps the open side of the second housing portion 5b to form the housing 5 with the storage space 5c. The first housing portion 5a and the second housing portion 5b can also both be hollow structures with one end open. The open side of the first housing portion 5a overlaps the open side of the second housing portion 5b to form the housing 5 with the storage space 5c. Of course, the first housing portion 5a and the second housing portion 5b can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0080] In order to improve the sealing performance after the first box body 5a and the second box body 5b are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 5a and the second box body 5b.

[0081] Assuming that the first box body portion 5a covers the top of the second box body portion 5b, the first box body portion 5a can also be called an upper box cover, and the second box body portion 5b can also be called a lower box body.

[0082] In the battery 2, there can be one or more battery cells 6. If there are multiple battery cells 6, the multiple battery cells 6 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections within the multiple battery cells 6. The multiple battery cells 6 can be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 6 can be housed within the housing 5. Alternatively, multiple battery cells 6 can be first connected in series, in parallel, or in a hybrid connection to form a battery module, and then the multiple battery modules can be connected in series, in parallel, or in a hybrid connection to form a single unit and housed within the housing 5.

[0083] Figure 3 is a schematic diagram of the three-dimensional structure of a battery cell provided in some embodiments of the present application; Figure 4 is a schematic diagram of a cross-sectional view of a battery cell provided in some embodiments of the present application; Figure 5 is a schematic diagram of an electrode assembly of a battery cell provided in some embodiments of the present application; and Figure 6 is a schematic diagram of a cross-sectional view of Figure 5 taken along the AA direction.

[0084] 3 to 6 , an embodiment of the present application provides a battery cell 6 , which includes a housing 20 and an electrode assembly 10 , wherein the electrode assembly 10 is accommodated in the housing 20 .

[0085] The electrode assembly 10 includes a positive electrode and a negative electrode. During the charge and discharge process of the battery cell 6, active ions (e.g., lithium ions) are intercalated and released between the positive and negative electrodes. Optionally, the electrode assembly 10 also includes a separator disposed between the positive and negative electrodes. The separator can reduce the risk of short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0086] The housing 20 is used to encapsulate the electrode assembly 10 and the electrolyte and other components. The housing 20 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0087] In some embodiments, the positive electrode includes a positive electrode sheet 10 a . The positive electrode sheet 10 a may include a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector.

[0088] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material layer is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0089] In some embodiments, the negative electrode includes a negative electrode sheet 10 b . The negative electrode sheet 10 b may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector.

[0090] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0091] In some embodiments, the electrode assembly 10 further includes a separator 10c, which is used to separate the positive electrode 10a from the negative electrode 10b. The separator 10c can reduce the risk of short circuit between the positive and negative electrodes while allowing active ions to pass through.

[0092] In some embodiments, the separator 10c includes a separator. The separator of the present application can be any known porous separator with good chemical stability and mechanical stability.

[0093] In some embodiments, the electrode assembly 10 includes one or more electrode units. The electrode units include a positive electrode sheet 10a, a negative electrode sheet 10b, and a separator 10c, which insulates the positive electrode sheet 10a from the negative electrode sheet 10b. As an example, the electrode units can be bare cells.

[0094] In some examples, there is one electrode unit; alternatively, there are multiple electrode units, and the multiple electrode units are stacked.

[0095] In some embodiments, the shape of the electrode assembly 10 can be cylindrical, flat, or polygonal.

[0096] In some embodiments, the shape of the electrode unit can be cylindrical, flat, or polygonal.

[0097] In some embodiments, the housing 20 includes a shell 21 and an end cover. The shell 21 has an opening, and the end cover is used to cover the opening.

[0098] The housing 21 is a component used to cooperate with the end cover to form an internal cavity of the battery cell 6. The formed internal cavity can be used to accommodate the electrode assembly 10, electrolyte and other components.

[0099] The housing 21 and the end cap can be independent components. For example, an opening can be provided on the housing 21, and the end cap can be closed at the opening to form an internal cavity of the battery cell 6.

[0100] The housing 21 can have various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the housing 21 can be determined according to the specific shape and size of the electrode assembly 10. The housing 21 can be made of various materials, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, aluminum-plastic film, steel-plastic film, etc.

[0101] The shape of the end cap can be adapted to the shape of the housing 21 to fit the housing 21. The material of the end cap can be the same as or different from the material of the housing 21. Optionally, the end cap can be made of a material with a certain hardness and strength (e.g., copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.). In this way, the end cap is less likely to deform when subjected to compression or collision, thereby providing the battery cell 6 with higher structural strength and improved reliability.

[0102] The end cover is connected to the housing 21 by welding, bonding, clamping or other means.

[0103] The housing 21 may be open at one end or at both ends. In some examples, the housing 21 may be a structure with an open end, and an end cap is provided and covers the housing 21 .

[0104] In other examples, the housing 21 may also be a structure with openings on both sides, with two end caps provided, each of which covers the two openings of the housing 21. Specifically, the housing 21 has a first opening 211 and a second opening 212 at both ends, and the two end caps are a first end cap 22 and a second end cap 23. The first end cap 22 is connected to the housing 21 and covers the first opening 211, and the second end cap 23 is connected to the housing 21 and covers the second opening 212.

[0105] In some embodiments, the electrode unit is a wound structure. For example, the positive electrode sheet 10a and the negative electrode sheet 10b are both strip-shaped structures, and the positive electrode sheet 10a, the separator 10c, and the negative electrode sheet 10b are wound into a wound structure.

[0106] In some embodiments, the electrode unit is a laminate structure.

[0107] As an example, a plurality of positive electrode sheets 10 a and a plurality of negative electrode sheets 10 b may be provided, and the plurality of positive electrode sheets 10 a and the plurality of negative electrode sheets 10 b may be alternately stacked.

[0108] As an example, a plurality of positive electrode sheets 10 a may be provided, and the negative electrode sheet 10 b may be folded to form a plurality of stacked folded segments, with one positive electrode sheet 10 a sandwiched between adjacent folded segments.

[0109] As an example, the positive electrode sheet 10 a and the negative electrode sheet 10 b are both folded to form a plurality of stacked folded sections.

[0110] In some embodiments, the electrode assembly 10 includes an electrode body 11, a first electrode tab 12, and a second electrode tab 13. The first electrode tab 12 and the second electrode tab 13 have opposite polarities. The first electrode tab 12 and the second electrode tab 13 can be led out from the same end of the electrode body 11, or from opposite ends of the electrode body 11.

[0111] As an example, the electrode body 11 may include a portion of the positive electrode current collector coated with a positive electrode active material layer, a positive electrode active material layer, a portion of the negative electrode current collector coated with a negative electrode active material layer, a negative electrode active material layer, and a separator 10c. The active material in the positive electrode active material layer and the active material in the negative electrode active material layer are used to electrochemically react with the electrolyte and the like to generate a charge and discharge process.

[0112] One of the first electrode tab 12 and the second electrode tab 13 is a positive electrode tab, and the other is a negative electrode tab. For example, the positive electrode tab may be the portion of the positive electrode current collector not coated with the positive electrode active material layer, and the negative electrode tab may be the portion of the negative electrode current collector not coated with the negative electrode active material layer.

[0113] As an example, the positive electrode tab includes a plurality of stacked aluminum foils, and the negative electrode tab includes a plurality of stacked copper foils.

[0114] In some embodiments, the first electrode tab 12 is a die-cut electrode tab or a flattened electrode tab, and the second electrode tab 13 is a die-cut electrode tab or a flattened electrode tab.

[0115] In some embodiments, there may be one or more first electrode tabs 12 .

[0116] In some embodiments, the electrode assembly 10 includes a plurality of stacked electrode units, each of which includes a main body, a first electrode tab 12, and a second electrode tab 13 extending from the main body. The main body may include a portion of the positive electrode current collector coated with a positive electrode active material layer, the positive electrode active material layer, a portion of the negative electrode current collector coated with a negative electrode active material layer, the negative electrode active material layer, and a separator 10c.

[0117] The electrode body 11 includes a main body portion of a plurality of electrode units.

[0118] In some embodiments, the battery cell 6 is provided with electrode terminals, which can be used to electrically connect the electrode assembly 10 to a circuit outside the battery cell 6 to enable charging and discharging of the electrode assembly 10 .

[0119] In some embodiments, the battery cell 6 has an electrode terminal, the first tab 12 is electrically connected to the electrode terminal, and the second tab 13 is electrically connected to the housing 20. The housing 20 and the electrode terminal can serve as two electrodes of the battery cell 6 electrically connected to an external circuit.

[0120] In other embodiments, the battery cell 6 includes a first electrode terminal 30 and a second electrode terminal 40 disposed in the housing 20 . The first electrode terminal 30 is electrically connected to the first electrode tab 12 , and the second electrode terminal 40 is electrically connected to the second electrode tab 13 .

[0121] As an example, the first electrode terminal 30 and the second electrode terminal 40 are located on the same side of the electrode body 11 , and the first electrode tab 12 and the second electrode tab 13 extend from the same end of the electrode body 11 .

[0122] As an example, the first electrode terminal 30 and the second electrode terminal 40 are respectively located on the same side of the electrode body 11 , the first electrode tab 12 extends from one end of the electrode body 11 facing the first electrode terminal 30 , and the second electrode tab 13 extends from one end of the electrode body 11 facing the second electrode terminal 40 .

[0123] In some embodiments, the battery cell 6 is a cylindrical battery cell or a square battery cell 6 .

[0124] Figure 7 is a structural schematic diagram of the first end cover assembly of the battery cell provided in some embodiments of the present application; Figure 8 is a side view schematic diagram of a partial structure of the battery cell provided in some embodiments of the present application; and Figure 9 is an enlarged schematic diagram of circle B in Figure 4.

[0125] 3 to 9 , an embodiment of the present application provides a battery cell 6, which includes a housing 20, a first electrode terminal 30, an electrode assembly 10, and a first insulating member 50. The housing 20 includes a first wall 20a and a second wall 20b surrounding the outer circumference of the first wall 20a. The first electrode terminal 30 is disposed on the first wall 20a. The electrode assembly 10 includes an electrode body 11 and a first electrode tab 12, the first electrode tab 12 extending from one end of the electrode body 11 facing the first wall 20a and electrically connected to the first electrode terminal 30. The first insulating member 50 includes a first insulating body 51 and a first limiting portion 52, at least a portion of the first insulating body 51 is located between the first wall 20a and the electrode body 11, the first limiting portion 52 protrudes from the first insulating body 51, and at least a portion of the first limiting portion 52 is located between the second wall 20b and the electrode body 11.

[0126] As an example, the first wall 20a and the second wall 20b can be integrally formed, for example, the first wall 20a and the second wall 20b are two walls of the housing 21. Alternatively, the first wall 20a and the second wall 20b are independently formed and connected by welding, clamping, bonding, or other processes. For example, the first wall 20a can be an end cap, and the second wall 20b can be the housing 21 or a portion of the housing 21.

[0127] As an example, the second wall 20b is disposed around the first wall 20a and may be in a cylindrical structure. Alternatively, the second wall 20b may be in a square cylindrical structure or a cylindrical structure.

[0128] The first tab 12 can be directly connected to the first electrode terminal 30 to electrically connect the first tab 12 to the first electrode terminal 30; for example, the first tab 12 is welded to the first electrode terminal 30. Alternatively, the first tab 12 is connected to the first electrode terminal 30 through other conductive structures (such as an adapter) to achieve electrical connection between the first tab 12 and the first electrode terminal 30.

[0129] The first insulating body 51 and the first limiting portion 52 can be integrally formed, for example, by injection molding. Alternatively, the first insulating body 51 and the first limiting portion 52 can be formed independently and connected by bonding, clamping, or welding.

[0130] The first insulating body 51 may be entirely located between the first wall 20 a and the electrode body 11 , or only a portion thereof may be located between the first wall 20 a and the electrode body 11 .

[0131] As an example, the first insulating body 51 may be connected to the first wall 20a. For example, the first insulating body 51 may be bonded to the first wall 20a, or the first insulating body 51 may be indirectly connected to the first wall 20a through other components.

[0132] As an example, the first insulating body 51 may or may not be in contact with the electrode body 11. Alternatively, the first insulating body 51 abuts against the electrode body 11.

[0133] There may be one or more first limiting portions 52 . As an example, there may be more than one first limiting portion 52 , and the first limiting portions 52 are spaced apart along the circumference of the electrode body 11 .

[0134] As an example, the first limiting portion 52 protrudes from a side of the first insulating body 51 facing away from the first wall 20 a.

[0135] The first limiting portion 52 may separate a portion of the second wall 20 b from the electrode body 11 , or may separate the entire second wall 20 b from the electrode body 11 .

[0136] The first limiting portion 52 may be connected to the electrode body 11 or may be provided independently of the electrode body 11 .

[0137] When the battery cell 6 is subjected to an external impact, the first insulating body 51 and the first limiting portion 52 can limit the vibration of the electrode body 11 in multiple directions, thereby reducing the tension on the first tab 12, reducing the risk of the first tab 12 tearing, and improving the reliability of the battery cell 6. In addition, the first insulating body 51 and the first limiting portion 52 can also provide insulation, reducing the risk of the first wall 20a and the second wall 20b connecting the positive and negative poles of the electrode body 11, thereby improving reliability.

[0138] In some embodiments, the battery cell 6 further includes a pressure relief mechanism 60 disposed on the housing 20. When a short circuit or overcharge occurs, the pressure relief mechanism 60 is activated to release the internal pressure of the battery cell 6 to the outside, thereby reducing the risk of explosion or fire of the battery cell 6.

[0139] The pressure relief mechanism 60 may be provided on the first wall 20 a or the second wall 20 b .

[0140] The pressure relief mechanism 60 is a component or element that is activated to release internal gas when the internal pressure or temperature of the battery cell 6 reaches a predetermined threshold. This threshold value varies depending on the design requirements. This threshold value may depend on the material of one or more of the positive electrode sheet 10a, negative electrode sheet 10b, electrolyte, and separator 10c in the battery cell 6.

[0141] The pressure relief mechanism 60 may take the form of an explosion-proof valve, an air valve, a pressure relief valve, or a safety valve, and may specifically be a pressure-sensitive element or structure. Specifically, when the internal pressure of the battery cell 6 reaches a predetermined threshold, the pressure relief mechanism 60 actuates, or a weak area within the pressure relief mechanism 60 ruptures, thereby forming an opening or passage through which the internal pressure can be released. Alternatively, the pressure relief mechanism 60 may be a temperature-sensitive element or structure. Specifically, when the internal temperature of the battery cell 6 reaches a predetermined threshold, the pressure relief mechanism 60 actuates, thereby forming an opening or passage through which the internal pressure can be released.

[0142] The "activation" mentioned in this application refers to the action of the pressure relief mechanism 60 or its activation to a certain state, thereby allowing the internal pressure of the battery cell 6 to be released. The action produced by the pressure relief mechanism 60 may include, but is not limited to: at least a portion of the pressure relief mechanism 60 is ruptured, broken, torn or opened, etc. When the pressure relief mechanism 60 is actuated, the high-temperature and high-pressure substances inside the battery cell 6 will be discharged outward from the actuated part as exhaust. In this way, the pressure of the battery cell 6 can be relieved under controllable pressure, thereby avoiding potential more serious accidents.

[0143] The emissions from the battery cells 6 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode sheets, separator fragments, high-temperature and high-pressure gases generated by the reaction, flames, and the like.

[0144] In some embodiments, the pressure relief mechanism 60 is disposed on the second wall 20b.

[0145] In some examples, the pressure relief mechanism 60 and the second wall 20b are independently formed components, and the two can be connected by welding, bonding or other means. Alternatively, the pressure relief mechanism 60 and the second wall 20b can be formed integrally.

[0146] In some embodiments, along the thickness direction of the pressure relief mechanism 60 , the pressure relief mechanism 60 does not overlap with the first limiting portion 52 .

[0147] When thermal runaway occurs in the battery cell 6, high-temperature substances released from the electrode body 11 can be discharged through the pressure relief channel formed by the pressure relief mechanism 60. The first limiter 52 does not overlap with the pressure relief mechanism 60, thereby reducing the first limiter 52's resistance to high-temperature substances and improving pressure relief efficiency.

[0148] In some embodiments, the thickness of the first limiting portion 52 is 0.1 mm to 1.5 mm. Optionally, the thickness of the first limiting portion 52 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, or 1.5 mm.

[0149] In this embodiment of the present application, the thickness of the first limiting portion 52 is limited to greater than or equal to 0.1 mm to increase the strength of the first limiting portion 52, reduce deformation of the first limiting portion 52 under the impact of the electrode body 11, increase the gap between the electrode body 11 and the second wall 20b, and improve the reliability of the battery cell 6. In this embodiment of the present application, the thickness of the first limiting portion 52 is limited to less than or equal to 1.5 mm to reduce the volume and weight of the first limiting portion 52, improve space utilization, and increase the energy density of the battery cell 6.

[0150] In some embodiments, the thickness of the first limiting portion 52 is 0.2 mm-0.8 mm.

[0151] In some embodiments, the first insulating body 51 and the first limiting portion 52 are integrally formed to improve the connection strength between the first insulating body 51 and the first limiting portion 52 and to simplify the assembly process of the first insulating member 50 .

[0152] In some embodiments, the first wall 20 a and the electrode body 11 are arranged along a first direction Z. Exemplarily, the first direction Z is parallel to a thickness direction of the first wall 20 a.

[0153] In some embodiments, the electrode body 11 has a dimension L1 along the first direction Z, and the portion of the first limiting portion 52 located between the second wall 20b and the electrode body 11 has a dimension L2 along the first direction Z, where L2 is smaller than L1. The first limiting portion 52 can have a smaller dimension than the electrode body 11 in the first direction Z to save space and improve energy density.

[0154] In some embodiments, the first insulating body 51 abuts against the electrode body 11 along the first direction Z. The first insulating body 51 can limit vibration of the electrode body 11 in the first direction Z, reducing the risk of tearing of the first electrode tab 12 .

[0155] In some embodiments, the battery cell 6 further includes a first connector 70 , which connects the electrode body 11 and the first limiting portion 52 .

[0156] The first limiting portion 52 may be connected to the electrode body 11 via one first connecting member 70 , or may be connected to the electrode body 11 via a plurality of first connecting members 70 .

[0157] The first connector 70 limits the relative movement between the first limiting portion 52 and the electrode body 11 . When the battery cell 6 is subjected to external impact, the first connector 70 can restrain the electrode body 11 , reduce the force applied to the first tab 12 , and reduce the risk of the first tab 12 tearing.

[0158] In some embodiments, the first connecting member 70 includes a first connecting portion 701 connected to the electrode body 11 and a second connecting portion 702 connected to the first limiting portion 52 . The first connecting member 70 is used to limit the relative movement between the first limiting portion 52 and the electrode body 11 .

[0159] As an example, the first connection portion 701 may be connected to the electrode body 11 by welding, bonding or other means, and the second connection portion 702 may be connected to the first limiting portion 52 by welding, bonding, clamping or other means.

[0160] In some embodiments, the first connection portion 701 is located on a side of the first limiting portion 52 away from the electrode body 11. When installing the first connector 70, there is no need to insert the first connector 70 between the electrode body 11 and the first limiting portion 52, thereby reducing assembly difficulty.

[0161] In some embodiments, the first connecting member 70 comprises adhesive tape, which is small in size and easy to assemble.

[0162] In some embodiments, the housing 20 includes a shell 21 and a first end cover 22. One end of the shell 21 has a first opening 211. The first end cover 22 is connected to the shell 21 and covers the first opening 211. The first end cover 22 is a first wall 20a.

[0163] Exemplarily, the first end cover 22 is welded to the housing 21 .

[0164] In some embodiments, the battery cell 6 includes a first end cap assembly, a housing 21, and an electrode assembly 10. The first end cap assembly includes a first end cap 22, a first insulating member 50, and a first electrode terminal 30. The first electrode terminal 30 is insulated and disposed on the first end cap 22. The first insulating member 50 is disposed on a side of the first end cap 22 facing the electrode assembly 10.

[0165] Exemplarily, the first insulating member 50 is snap-connected to the first end cover 22 .

[0166] Exemplarily, the battery cell 6 can be assembled according to the following steps: connecting the first electrode tab 12 of the electrode assembly 10 to the first electrode terminal 30; bonding the first connector 70 to the first limiting portion 52 and the electrode body 11 of the electrode assembly 10; installing the electrode assembly 10 into the shell 21; and welding the first end cover 22 and the shell 21.

[0167] The first connecting member 70 can connect the electrode body 11 to the first limiting portion 52. During the process of the electrode assembly 10 being put into the shell or the transportation of the electrode assembly 10, the first insulating component 50 can restrain the electrode body 11 through the first connecting member 70, limit the relative movement between the electrode body 11 and the first insulating component 50, reduce the force on the first pole ear 12, and reduce the risk of the first pole ear 12 tearing.

[0168] 10 is an enlarged schematic diagram of the circle C in FIG. 4 ; FIG. 11 is an enlarged schematic diagram of the circle D in FIG. 4 ; and FIG. 12 is a structural schematic diagram of a second insulating member provided in some embodiments of the present application.

[0169] 8 to 12 , in some embodiments, the housing 20 includes a third wall 20 c , the first wall 20 a and the third wall 20 c are oppositely disposed along the first direction Z, and the second wall 20 b connects the first wall 20 a and the third wall 20 c .

[0170] As an example, the third wall 20c and the second wall 20b can be integrally formed, for example, the third wall 20c and the second wall 20b are two walls of the housing 21. Alternatively, the third wall 20c and the second wall 20b are independently formed and connected by welding, clamping, bonding, or other processes. For example, the third wall 20c can be an end cap, and the second wall 20b can be the housing 21 or a portion of the housing 21.

[0171] In some embodiments, the battery cell 6 further includes a second electrode terminal 40 , and the electrode assembly 10 further includes a second electrode tab 13 . The second electrode terminal 40 is electrically connected to the second electrode tab 13 .

[0172] The second tab 13 can be directly connected to the second electrode terminal 40 to electrically connect the second tab 13 to the second electrode terminal 40; for example, the second tab 13 is welded to the second electrode terminal 40. Alternatively, the second tab 13 is connected to the second electrode terminal 40 through other conductive structures (such as an adapter) to achieve electrical connection between the second tab 13 and the second electrode terminal 40.

[0173] In some embodiments, the first electrode tab 12 and the second electrode tab 13 have opposite polarities. Correspondingly, the first electrode terminal 30 and the second electrode terminal 40 have opposite polarities. One of the first electrode terminal 30 and the second electrode terminal 40 is a positive terminal, and the other is a negative terminal.

[0174] In some embodiments, the battery cell 6 further includes a second electrode terminal 40 disposed on the third wall 20 c , and the electrode assembly 10 includes a second electrode tab 13 extending from one end of the electrode body 11 facing the third wall 20 c and electrically connected to the second electrode terminal 40 .

[0175] In some embodiments, the battery cell 6 also includes a second insulating component 80, the second insulating component 80 includes a second insulating body 81 and a second limiting portion 82, at least a portion of the second insulating body 81 is located between the third wall 20c and the electrode body 11, the second limiting portion 82 protrudes from the second insulating body 81, and at least a portion of the second limiting portion 82 is located between the second wall 20b and the electrode body 11.

[0176] The second insulating body 81 and the second limiting portion 82 can be integrally formed, for example, by injection molding. Alternatively, the second insulating body 81 and the second limiting portion 82 can be formed independently and connected by bonding, clamping, or welding.

[0177] The second insulating body 81 may be entirely located between the third wall 20 c and the electrode body 11 , or only a portion thereof may be located between the third wall 20 c and the electrode body 11 .

[0178] As an example, the second insulating body 81 may be connected to the third wall 20c. For example, the second insulating body 81 may be bonded to the third wall 20c, or the second insulating body 81 may be indirectly connected to the third wall 20c through other components.

[0179] As an example, the second insulating body 81 may or may not be in contact with the electrode body 11. Optionally, the second insulating body 81 abuts against the electrode body 11.

[0180] There may be one or more second limiting portions 82 . As an example, there may be more than one second limiting portion 82 , and the plurality of second limiting portions 82 are spaced apart along the circumferential direction of the electrode body 11 .

[0181] As an example, the second limiting portion 82 protrudes from a side of the second insulating body 81 facing away from the third wall 20 c.

[0182] The second limiting portion 82 may separate a portion of the second wall 20 b from the electrode body 11 , or may separate the entire second wall 20 b from the electrode body 11 .

[0183] The second limiting portion 82 may be connected to the electrode body 11 or may be provided independently of the electrode body 11 .

[0184] When the battery cell 6 is subjected to an external impact, the second insulating body 81 and the second limiting portion 82 can limit the vibration of the electrode body 11 in multiple directions, thereby reducing the tension on the second electrode tab 13, reducing the risk of the second electrode tab 13 tearing, and improving the reliability of the battery cell 6. In addition, the second insulating body 81 and the second limiting portion 82 can also provide insulation, reducing the risk of the third wall 20c and the second wall 20b connecting the positive and negative poles of the electrode body 11, thereby improving reliability.

[0185] In some embodiments, along the thickness direction of the pressure relief mechanism 60 , the pressure relief mechanism 60 does not overlap with the second limiting portion 82 , thereby reducing the obstruction of the second limiting portion 82 to high-temperature substances and improving the pressure relief efficiency.

[0186] In some embodiments, the thickness of the second limiting portion 82 is 0.1 mm to 1.5 mm. Optionally, the thickness of the second limiting portion 82 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, or 1.5 mm.

[0187] In some embodiments, the thickness of the second limiting portion 82 is 0.2 mm-0.8 mm.

[0188] In some embodiments, the thickness of the first limiting portion 52 is equal to the thickness of the second limiting portion 82 .

[0189] In some embodiments, the second insulating body 81 and the second limiting portion 82 are integrally formed to improve the connection strength between the second insulating body 81 and the second limiting portion 82 and to simplify the assembly process of the second insulating member 80 .

[0190] In some embodiments, the second insulating body 81 has a through hole 811, through which the second tab 13 passes and is connected to the second electrode terminal 40. The second insulating body 81 can support the second tab 13, reducing the risk of the second tab 13 being inserted into the electrode body 11, thereby improving reliability.

[0191] In some embodiments, the second insulating body 81 is opposite to the electrode body 11 along the first direction Z. The first insulating body 51 and the second insulating body 81 may constrain the electrode body 11 from both sides of the first direction Z.

[0192] In some examples, the battery cell 6 further includes a second connector 71 , which connects the electrode body 11 and the second limiting portion 82 .

[0193] The second connector 71 limits the relative movement between the second limiting portion 82 and the electrode body 11 . When the battery cell 6 is subjected to external impact, the second connector 71 can restrain the electrode body 11 , reduce the force exerted on the second tab 13 , and reduce the risk of the second tab 13 tearing.

[0194] In some embodiments, the second connecting member 71 includes adhesive tape.

[0195] In some embodiments, the battery cell 6 further includes a third insulating member 90 , at least a portion of which is located between the third wall 20 c and the second insulating body 81 , and the third insulating member 90 connects the third wall 20 c and the second insulating body 81 .

[0196] The third insulating member 90 can be connected to the second insulating body 81 by bonding, clamping or other means. The third insulating member 90 can be connected to the three walls by bonding, clamping or other means.

[0197] The third insulating member 90 can further improve the insulation effect and enhance the reliability. The third insulating member 90 can fix the second insulating member 80 to the third wall 20 c, thereby enhancing the stability of the second insulating member 80 .

[0198] In some embodiments, the first limiting portion 52 and the second limiting portion 82 are spaced apart along the first direction Z to reduce the risk of interference between the first limiting portion 52 and the second limiting portion 82 .

[0199] In some embodiments, in the first direction Z, the size of the electrode body 11 is L1, the portion of the first limiting portion 52 located between the electrode body 11 and the second wall 20b is L2, and the portion of the second limiting portion 82 located between the electrode body 11 and the second wall 20b is L3. 0.2≤(L2+L3) / L1≤0.8.

[0200] Optionally, (L2+L3) / L1 is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 or 0.8.

[0201] In this embodiment of the present application, (L2 + L3) / L1 is limited to greater than or equal to 0.2 to increase the area where the electrode body 11 is constrained, reduce the vibration amplitude of the electrode body 11, reduce the risk of tab tearing, and improve the reliability of the battery cell 6. In this embodiment of the present application, (L2 + L3) / L1 is limited to less than or equal to 0.8 to reduce the space occupied by the first limit portion 52 and the second limit portion 82, thereby increasing the energy density of the battery cell 6.

[0202] In some embodiments, L2 is equal to L3.

[0203] In some embodiments, L2 is ≥ 2 mm. Optionally, L2 is 2 mm, 3 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, or 20 mm.

[0204] In some embodiments, L2 ≥ 5 mm.

[0205] In some embodiments, L3 is ≥ 2 mm. Optionally, L3 is 2 mm, 3 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, or 20 mm.

[0206] In some embodiments, L3 ≥ 5 mm.

[0207] In some embodiments, the housing 20 includes a shell 21, a first end cap 22, and a second end cap 23. The shell 21 has a first opening 211 and a second opening 212 at both ends along the first direction Z. The first end cap 22 is connected to the shell 21 and covers the first opening 211. The second end cap 23 is connected to the shell 21 and covers the second opening 212. The first end cap 22 is a first wall 20a, the shell 21 is a second wall 20b, and the second end cap 23 is a third wall 20c.

[0208] Exemplarily, the second end cover 23 is welded to the housing 21 .

[0209] In some embodiments, the battery cell 6 includes a first end cap assembly, a second end cap assembly, a second insulating member 80, a housing 21, and an electrode assembly 10. The first end cap assembly includes a first end cap 22, a first insulating member 50, and a first electrode terminal 30. The first electrode terminal 30 is insulated and disposed on the first end cap 22. The first insulating member 50 is disposed on the side of the first end cap 22 facing the electrode assembly 10. The first end cap assembly includes a second end cap 23, a third insulating member 90, and a second electrode terminal 40. The second electrode terminal 40 is insulated and disposed on the second end cap 23. The third insulating member 90 is disposed on the side of the second end cap 23 facing the electrode assembly 10.

[0210] For example, the battery cell 6 can be assembled according to the following steps:

[0211] Step (100): Connecting the first tab 12 of the electrode assembly 10 to the first electrode terminal 30 of the first end cap assembly;

[0212] Step (200): bonding the first connecting member 70 to the first limiting portion 52 and the electrode body 11 of the electrode assembly 10;

[0213] Step (300): Pass the second electrode tab 13 through the through hole 811 of the second insulating body 81 of the second insulating member 80, and make the second insulating body 81 abut against the electrode body 11;

[0214] Step (400): bonding the second connecting member 71 to the second limiting portion 82 and the electrode body 11 of the electrode assembly 10;

[0215] Step (500): inserting the second insulating member 80 and the electrode body 11 into the housing 21 through the first opening 211 of the housing 21, and extending the second electrode tab 13 from the second opening 212;

[0216] Step (600): Connecting the second electrode tab 13 to the second electrode terminal 40 of the second end cap assembly;

[0217] Step (700): welding the first end cover 22 and the housing 21;

[0218] Step (800): bend the second electrode tab 13 and clamp the third insulating member 90 of the second end cap assembly to the second insulating member 80;

[0219] Step (900) is to weld the second end cover 23 and the housing 21.

[0220] Step (600) and step (700) are performed in no particular order.

[0221] Since the first connecting member 70 connects the electrode body 11 to the first limiting portion 52, and the second connecting member 71 connects the electrode body 11 to the second limiting portion 82, in step (500) or in the transportation process before step (500), the first insulating member 50 can restrain the electrode body 11 through the first connecting member 70, limiting the relative movement between the electrode body 11 and the first insulating member 50, and the second insulating member 80 is connected to the electrode body 11 and is not easy to fall off from the electrode body 11.

[0222] The second insulating body 81 of the second insulating member 80 can block the second electrode tab 13 during the bending process, thereby reducing the risk of the second electrode tab 13 being inserted into the electrode body 11 and improving reliability.

[0223] In some embodiments, the first insulating member 50 , the second insulating member 80 , and the third insulating member 90 are all made of plastic.

[0224] FIG13 is another schematic cross-sectional view of a battery cell provided in some embodiments of the present application; FIG14 is an enlarged schematic view of the circle frame of FIG13 .

[0225] 9 , 13 , and 14 , in some embodiments, the first insulating member 50 includes two first limiting portions 52, which are located on opposite sides of the electrode body 11. The two first limiting portions 52 can limit the electrode body 11 from both sides to reduce movement of the electrode body 11 within the housing 20 and reduce the risk of tearing of the first tab 12.

[0226] As an example, the two first limiting portions 52 are respectively located on two sides of the electrode body 11 along the second direction X.

[0227] As an example, the second direction X is perpendicular to the first direction Z.

[0228] As an example, the thickness direction of the pressure relief mechanism is parallel to the second direction X.

[0229] In some embodiments, the first limiting portion 52 is in the shape of a flat plate.

[0230] In some embodiments, the second limiting portion is in the shape of a flat plate.

[0231] In some embodiments, the battery cell 6 includes two first connectors 70, which respectively connect the two first limiting portions 52 to the electrode body 11. In alternative embodiments, the battery cell 6 includes one first connector 70, which connects the two first limiting portions 52 to the electrode body 11. For example, the first connector 70 surrounds the electrode body 11 for at least one cycle.

[0232] In some embodiments, the second insulating member 80 includes two second limiting portions 82 , and the two second limiting portions 82 are respectively located on opposite sides of the electrode body 11 .

[0233] As an example, the two second limiting portions 82 are respectively located on two sides of the electrode body 11 along the second direction X.

[0234] In some embodiments, the battery cell 6 includes two second connectors 71 , and the two second connectors 71 respectively connect the two second limiting portions 82 to the electrode body 11 .

[0235] In some embodiments, the first wall 20a is located on one side of the electrode body 11 along the first direction Z, and the first stopper 52 is located on one side of the electrode body 11 along the second direction X. In the third direction Y, both ends of the first stopper 52 do not extend beyond the electrode body 11. The first direction Z, the second direction X, and the third direction Y are perpendicular to each other. In the third direction Y, the first stopper 52 and the electrode body 11 share space, thereby improving space utilization and increasing energy density.

[0236] For example, after the first end cap assembly and the electrode assembly 10 are assembled, the electrode body 11 can be placed on the side of the conveyor belt along the third direction Y; at this time, the first limiting portion 52 is spaced from the conveyor belt, and the first limiting portion 52 does not need to bear the gravity of the electrode body 11, thereby reducing the risk of relative movement between the first limiting portion 52 and the electrode body 11 along the third direction Y.

[0237] In some embodiments, in the third direction Y, both ends of the second limiting portion 82 do not extend beyond the electrode body 11 .

[0238] In some embodiments, in the third direction Y, the size of the first limiting portion 52 is equal to the size of the second limiting portion 82 .

[0239] In some embodiments, the dimension of the first limiting portion 52 along the third direction Y is less than or equal to the dimension of the electrode body 11 along the third direction Y. Optionally, the dimension of the first limiting portion 52 along the third direction Y is 0.6 to 0.95 times the dimension of the electrode body 11 along the third direction Y.

[0240] In some embodiments, the dimension of the second limiting portion 82 along the third direction Y is less than or equal to the dimension of the electrode body 11 along the third direction Y. Optionally, the dimension of the second limiting portion 82 along the third direction Y is 0.6 to 0.95 times the dimension of the electrode body 11 along the third direction Y.

[0241] In some embodiments, the first wall 20a is located on one side of the electrode body 11 along the first direction Z. The electrode body 11 includes two first outer surfaces 111 arranged opposite each other along the second direction X and two second outer surfaces 112 arranged opposite each other along the third direction Y. The area of ​​the first outer surface 111 is smaller than the area of ​​the second outer surface 112. The first direction Z, the second direction X, and the third direction Y are perpendicular to each other. The first stopper 52 is located between the first outer surface 111 and the second wall 20b.

[0242] During the charging process of the battery cell 6, the electrode body 11 expands. When the electrode body 11 expands, the deformation of the first outer surface 111 is relatively small. Positioning the first limiting portion 52 between the first outer surface 111 and the second wall 20b can reduce the expansion force exerted on the first limiting portion 52 and thus reduce its deformation. When the electrode body 11 expands, the deformation of the second outer surface 112 is relatively large. Positioning the first limiting portion 52 away from the second outer surface 112 can reduce the risk of the first limiting portion 52 squeezing the second outer surface 112, thereby reducing stress concentration on the second outer surface 112, lowering the risk of electrode fracture and ion precipitation, and improving the reliability of the battery cell 6.

[0243] In some embodiments, the second outer surface 112 is generally planar.

[0244] In some embodiments, at least a portion of the first outer surface 111 is arc-shaped.

[0245] In some embodiments, the first outer surface 111 and the second outer surface 112 are formed on the isolation member 10 c .

[0246] In some embodiments, at least a portion of the first connector 70 is bonded to the first outer surface 111 . Alternatively, the first connector 70 is not bonded to the second outer surface 112 .

[0247] In some embodiments, at least a portion of the second connecting member 71 is bonded to the first outer surface 111 . Alternatively, the second connecting member 71 is not bonded to the second outer surface 112 .

[0248] In some embodiments, the positive electrode sheet 10 a and the negative electrode sheet 10 b of the electrode assembly 10 are stacked along the third direction Y.

[0249] In some embodiments, the battery cell 6 is a square-shell battery cell.

[0250] In some embodiments, the first wall 20a is located on one side of the electrode body 11 along the first direction Z. The second wall 20b includes two first sub-walls 213, two second sub-walls 214, and four bent walls 215. The two first sub-walls 213 are arranged opposite each other along the second direction X, and the two second sub-walls 214 are arranged opposite each other along the third direction Y. Each bent wall 215 connects the first sub-walls 213 and the second sub-walls 214. The first direction Z, the second direction X, and the third direction Y are perpendicular to each other. In the second direction X, the first limiter 52 is located between the first sub-wall 213 and the electrode body 11, and the first limiter 52 does not overlap with the bent walls 215.

[0251] The bent wall 215 can disperse stress and reduce the risk of rupture of the housing 20. The first limiting portion 52 does not overlap with the bent wall 215, thereby reducing the risk of the first limiting portion 52 being deformed when squeezed by the electrode body 11.

[0252] In some embodiments, in the second direction X, the second limiting portion 82 is located between the first sub-wall 213 and the electrode body 11 , and the second limiting portion 82 does not overlap with the bent wall 215 .

[0253] In some embodiments, in the third direction Y, the size of the first sub-wall 213 is larger than the size of the first limiting portion 52 , and the size of the first sub-wall 213 is larger than the size of the second limiting portion 82 .

[0254] In some embodiments, when the battery cell 6 is placed sideways, that is, when the second direction X is parallel to the vertical direction, the first limiting portion 52 and the second limiting portion 82 can also support the electrode body 11, reducing the risk of the bending wall 215 squeezing the electrode body 11.

[0255] In some embodiments, the inner surface of the bent wall 215 is an arc surface, and the radius of the arc surface is greater than the thickness of the first limiting portion 52 .

[0256] FIG15 is a schematic cross-sectional view of a battery cell provided in some other embodiments of the present application.

[0257] 15 , in some embodiments, the electrode body 11 includes a straight region 11 a and a bent region 11 b , the bent region 11 b is located on one side of the straight region 11 a , and the first electrode tab is connected to the straight region 11 a .

[0258] The flat region 11a is a region of the electrode assembly 10 having a flat structure. In the flat region 11a, the positive electrode sheets 10a and the negative electrode sheets 10b are arranged substantially flat. For example, the surface of each layer of the positive electrode sheets 10a and the surface of each layer of the negative electrode sheets 10b in the flat region 11a are substantially planar.

[0259] The bending region 11b is a region of the electrode assembly 10 having a bent structure. Both the positive electrode sheet 10a and the negative electrode sheet 10b are bent in the bending region 11b. For example, the portion of the positive electrode sheet 10a located in the bending region 11b is generally bent into an arc shape, and the portion of the negative electrode sheet 10b located in the bending region 11b is generally bent into an arc shape.

[0260] In some embodiments, the first limiting portion 52 is located on a side of the bending region 11b away from the straight region 11a. The first limiting portion 52 can constrain the bending region 11b and reduce deformation of the bending region 11b during the charge and discharge process of the battery cell 6.

[0261] In some embodiments, the second limiting portion 82 is located on a side of the bending region 11 b away from the straight region 11 a .

[0262] In some embodiments, the first connecting member 70 and the second connecting member 71 are both connected to the bending region 11 b .

[0263] In some embodiments, a first recess 521 is defined on a side of the first limiting portion 52 facing the bending region 11 b , and the bending region 11 b is at least partially accommodated in the first recess 521 .

[0264] By providing the first recess 521 , the area of ​​the portion of the first limiting portion 52 that can contact the bending zone 11 b can be increased, so that the first limiting portion 52 can more effectively restrain the bending zone 11 b and reduce deformation of the bending zone 11 b.

[0265] In some embodiments, the first concave portion 521 is a contoured concave portion corresponding to the shape of the bending region 11 b .

[0266] In some embodiments, a second recess is provided on a side of the second limiting portion 82 facing the bending area 11 b , and a portion of the bending area 11 b is accommodated in the second recess.

[0267] FIG16 is a schematic cross-sectional view of a battery cell provided in some other embodiments of the present application.

[0268] As shown in FIG16 , in some embodiments, the first limiting portion 52 surrounds the electrode body 11. The first limiting portion 52 can limit the electrode body 11 from the periphery, reduce vibration of the electrode body 11, and improve the reliability of the battery cell 6.

[0269] In some embodiments, the battery cells 6 are cylindrical battery cells.

[0270] In some embodiments, the second limiting portion surrounds the electrode body 11 .

[0271] According to some embodiments of the present application, the present application further provides a battery comprising a plurality of battery cells 6 according to any one of the above embodiments.

[0272] According to some embodiments of the present application, the present application further provides an electrical device comprising a battery cell 6 according to any of the above embodiments, the battery cell 6 being used to provide electrical energy to the electrical device. The electrical device may be any of the aforementioned devices or systems using the battery cell 6.

[0273] 3 to 14 , an embodiment of the present application provides a battery cell 6 , which includes a housing 21 , an electrode assembly 10 , a first end cap assembly, a second end cap assembly, a second insulating member 80 , a first connector 70 , and a second connector 71 .

[0274] The housing 21 has a first opening 211 and a second opening 212 at both ends along the first direction Z. At least a portion of the electrode assembly 10 is accommodated in the housing 21 .

[0275] The first end cap assembly includes a first end cap 22 , a first insulating member 50 and a first electrode terminal 30 . The first end cap 22 covers the first opening 211 . The first electrode terminal 30 is insulated and disposed on the first end cap 22 . The first insulating member 50 is disposed on a side of the first end cap 22 facing the electrode assembly 10 .

[0276] The first end cap assembly includes a second end cap 23 , a third insulating member 90 and a second electrode terminal 40 . The second end cap 23 covers the second opening 212 . The second electrode terminal 40 is insulated and disposed on the second end cap 23 . The third insulating member 90 is disposed on a side of the second end cap 23 facing the electrode assembly 10 .

[0277] The electrode assembly 10 includes an electrode body 11, a first electrode tab 12 and a second electrode tab 13. The first electrode tab 12 and the second electrode tab 13 have opposite polarities. The first electrode tab 12 extends from one end of the electrode body 11 facing the first end cover 22 and is electrically connected to the first electrode terminal 30. The second electrode tab 13 extends from one end of the electrode body 11 facing the first end cover 22 and is electrically connected to the second electrode terminal 40.

[0278] The first insulating member 50 includes a first insulating body 51 and two first stoppers 52. At least a portion of the first insulating body 51 is located between the first end cap 22 and the electrode body 11. The first insulating body 51 is fixed to the first end cap 22 and abuts against the electrode body 11. The first stoppers 52 protrude from the side of the first insulating body 51 facing away from the first end cap 22. The two first stoppers 52 are located on either side of the electrode body 11 along a second direction X, which is perpendicular to the first direction Z. In the second direction X, at least a portion of the first stoppers 52 is located between the housing 21 and the electrode body 11.

[0279] The second insulating member 80 includes a second insulating body 81 and two second stoppers 82. At least a portion of the second insulating body 81 is located between the third insulating member 90 and the electrode body 11. The second insulating body 81 is fixed to the third insulating member 90 and abuts against the electrode body 11. The second stoppers 82 protrude from the side of the second insulating body 81 facing away from the second end cap 23. The two second stoppers 82 are located on either side of the electrode body 11 along the second direction X. In the second direction X, at least a portion of the second stoppers 82 is located between the housing 21 and the electrode body 11.

[0280] In the first direction Z, the first limiting portion 52 and the second limiting portion 82 are spaced apart from each other.

[0281] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0282] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, comprising: a housing comprising a first wall and a second wall surrounding a periphery of the first wall; a first electrode terminal, disposed on the first wall; an electrode assembly comprising an electrode body and a first electrode tab, wherein the first electrode tab extends from one end of the electrode body facing the first wall and is electrically connected to the first electrode terminal; as well as The first insulating component includes a first insulating body and a first limiting portion, at least a portion of the first insulating body is located between the first wall and the electrode body, the first limiting portion protrudes from the first insulating body, and at least a portion of the first limiting portion is located between the second wall and the electrode body. 2 . The battery cell according to claim 1 , further comprising a pressure relief mechanism disposed on the second wall; along a thickness direction of the pressure relief mechanism, the pressure relief mechanism does not overlap with the first limiting portion.

3. The battery cell according to claim 1 or 2, wherein: The thickness of the first limiting portion is 0.1 mm-1.5 mm.

4. The battery cell according to any one of claims 1 to 3, wherein: The first insulating body and the first limiting portion are formed integrally.

5. The battery cell according to any one of claims 1 to 4, wherein: The first wall and the electrode body are arranged along a first direction; The size of the electrode body along the first direction is L1, and the size of a portion of the first limiting portion located between the second wall and the electrode body along the first direction is L2, which is smaller than L1. 6 . The battery cell according to claim 1 , further comprising a first connector connecting the electrode body and the first limiting portion.

7. The battery cell according to claim 6, wherein: The first connecting member includes a first connecting portion connected to the electrode body and a second connecting portion connected to the first limiting portion. The first connecting member is used to limit relative movement between the first limiting portion and the electrode body.

8. The battery cell according to claim 6 or 7, wherein: The first connecting member includes an adhesive tape.

9. The battery cell according to any one of claims 1 to 8, wherein: The housing includes a third wall, the first wall and the third wall are arranged opposite to each other along a first direction, and the second wall connects the first wall and the third wall; The battery cell further includes a second electrode terminal disposed on the third wall, and the electrode assembly includes a second electrode tab extending from one end of the electrode body facing the third wall and electrically connected to the second electrode terminal; The battery cell also includes a second insulating component, which includes a second insulating body and a second limiting portion, at least a portion of the second insulating body is located between the third wall and the electrode body, the second limiting portion protrudes from the second insulating body, and at least a portion of the second limiting portion is located between the second wall and the electrode body.

10. The battery cell according to claim 9, wherein: The second insulating body is provided with a through hole, and the second electrode tab passes through the through hole and is connected to the second electrode terminal.

11. The battery cell according to claim 9 or 10, wherein: The battery cell further includes a third insulating member, at least a portion of which is located between the third wall and the second insulating body, and the third insulating member connects the third wall and the second insulating body.

12. The battery cell according to any one of claims 9 to 11, wherein: The first limiting portion and the second limiting portion are spaced apart along the first direction.

13. The battery cell according to any one of claims 9 to 12, wherein: In the first direction, the size of the electrode body is L1, the portion of the first limiting portion located between the electrode body and the second wall is L2, and the portion of the second limiting portion located between the electrode body and the second wall is L3; Among them, 0.2≤(L2+L3) / L1≤0.

8.

14. The battery cell according to any one of claims 9 to 13, wherein: The housing includes a shell, a first end cover and a second end cover. The shell has a first opening and a second opening at both ends along the first direction. The first end cover is connected to the shell and covers the first opening. The second end cover is connected to the shell and covers the second opening. The first end cover is the first wall, the shell is the second wall, and the second end cover is the third wall.

15. The battery cell according to any one of claims 1 to 13, wherein: The housing comprises a shell and a first end cover, one end of the shell has a first opening, and the first end cover is connected to the shell and covers the first opening; The first end cover is the first wall.

16. The battery cell according to any one of claims 1 to 15, wherein: The first insulating component includes two first limiting portions, and the two first limiting portions are respectively located on two opposite sides of the electrode body.

17. The battery cell according to any one of claims 1 to 16, wherein: The first wall is located on one side of the electrode body along the first direction, and the first limiting portion is located on one side of the electrode body along the second direction; In the third direction, both ends of the first limiting portion do not extend beyond the electrode body; The first direction, the second direction, and the third direction are perpendicular to each other.

18. The battery cell according to any one of claims 1 to 17, wherein: The first wall is located on one side of the electrode body along the first direction; The electrode body includes two first outer surfaces arranged opposite to each other along a second direction and two second outer surfaces arranged opposite to each other along a third direction, the area of ​​the first outer surface is smaller than the area of ​​the second outer surface, and the first direction, the second direction and the third direction are perpendicular to each other; The first limiting portion is located between the first outer surface and the second wall.

19. The battery cell according to any one of claims 1 to 18, wherein: The first wall is located on one side of the electrode body along the first direction; The second wall includes two first sub-walls, two second sub-walls, and four bent walls, wherein the two first sub-walls are arranged opposite to each other along the second direction, and the two second sub-walls are arranged opposite to each other along the third direction. Each bent wall connects the first sub-wall and the second sub-wall, and the first direction, the second direction, and the third direction are perpendicular to each other. In the second direction, the first limiting portion is located between the first sub-wall and the electrode body, and the first limiting portion does not overlap with the bending wall.

20. The battery cell according to any one of claims 1 to 19, wherein: The electrode body includes a straight area and a bent area, the bent area is located on one side of the straight area, and the first electrode tab is connected to the straight area; The first limiting portion is located on a side of the bending area away from the straight area.

21. The battery cell according to claim 20, wherein: A first recess is provided on a side of the first limiting portion facing the bending area, and a portion of the bending area is accommodated in the first recess.

22. The battery cell according to any one of claims 1 to 15, wherein: The first limiting portion surrounds the electrode body.

23. A battery comprising a plurality of battery cells according to any one of claims 1 to 22.

24. An electrical device comprising the battery according to claim 23, wherein the battery is used to provide electrical energy.

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