Battery monomer and preparation method thereof, battery, power utilization device and energy storage device

Abstract

The embodiment of the invention provides a battery monomer and a preparation method thereof, a battery, a power utilization device and an energy storage device. The insulation performance in the battery monomer can be improved. The battery cell includes: a housing; an electrode assembly, which is accommodated in the housing; the electrode terminal is arranged on the shell; the connecting component is used for connecting the electrode terminal and the electrode assembly, and at least part of the surface, facing the shell, of the connecting component is provided with a first insulating part.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of batteries, and more specifically, to a battery cell and a preparation method thereof, a battery, an electrical device, and an energy storage device. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. In this case, electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] An insulating structure is often required in a battery cell to reduce the possibility of internal short circuits in the battery cell. The insulation performance inside the battery cell is an important factor in measuring the reliability of the battery. Therefore, how to improve the insulation performance inside the battery cell is still a problem that needs to be solved. Summary of the invention

[0004] The embodiments of the present application provide a battery cell and a preparation method thereof, a battery, an electrical device, and an energy storage device, which can improve the insulation performance inside the battery cell.

[0005] In a first aspect, a battery cell is provided, comprising: a shell; an electrode assembly, the electrode assembly being accommodated in the shell; an electrode terminal, the electrode terminal being arranged on the shell; a connecting member, the connecting member being used to connect the electrode terminal and the electrode assembly, and a first insulating portion being arranged on at least a portion of the surface of the connecting member facing the shell.

[0006] In the embodiment of the present application, the first insulating part can achieve insulation between the connecting member and the shell, and can reduce the possibility of the shell being charged through the electrical connection between the connecting member and the electrode assembly when the distance between the connecting member and the shell is small, thereby improving the reliability of the battery cell. On the other hand, when the connecting member and the shell are pre-assembled together, it is difficult to set the insulating component after the connecting member and the shell are pre-assembled. Therefore, the first insulating part can also reduce the difficulty of setting the insulating component between the connecting member and the shell, and improve the processing efficiency of the battery cell.

[0007] In some embodiments, the connecting member includes a first connecting portion connected to the electrode assembly, and the first insulating portion includes a first insulating layer, which is disposed on a surface of the first connecting portion facing away from the electrode assembly.

[0008] The distance between the first connection part and the outer shell of the battery cell is relatively close. In the absence of the first insulating layer, the first connection part and the outer shell are easily in contact, causing the outer shell to be charged. Therefore, the first insulating layer can achieve insulation between the connection member and the outer shell, reduce the possibility of the outer shell being charged, and thus improve the reliability of the battery cell.

[0009] In some embodiments, a second insulating portion is disposed on at least a portion of the surface of the first connecting portion that faces the electrode assembly.

[0010] The second insulating portion can provide insulation for the connecting member on the side of the first insulating portion facing the electrode assembly, thereby improving the insulating performance of the first connecting portion of the connecting member.

[0011] In some embodiments, the second insulating portion is disposed on an edge of a surface of the first connecting portion facing the electrode assembly, and a portion of the surface of the first connecting portion facing the electrode assembly where the second insulating portion is not disposed is connected to a tab of the electrode assembly.

[0012] In this way, the edge area of ​​the first connection portion can be insulated and protected, thereby reducing the possibility that the edge area of ​​the first connection portion contacts the shell and causes the shell to be charged.

[0013] In some embodiments, the first connecting portion has a first surface, which connects the surface of the first connecting portion facing the electrode assembly and the surface of the first connecting portion facing away from the electrode assembly; the first insulating portion includes a second insulating layer, which is disposed on at least a portion of the first surface.

[0014] Providing a second insulating layer on the first surface can allow the surface of the first connection portion facing the outer shell of the battery cell to cover as much of the insulating structure as possible, thereby improving the insulation performance of the first connection portion and improving the reliability of the battery cell.

[0015] In some embodiments, the second insulating layer is connected to at least one of the first insulating layer and the second insulating portion.

[0016] This can not only improve the insulation performance at the corner of the first connection part, but also increase the adhesion of the first insulating layer, the second insulating layer and the second insulating part on the surface of the first connection part, improve the insulation performance of the corresponding part on the first connection part, and thus improve the reliability of the battery cell. When the second insulating layer is connected to the first insulating layer and the second insulating part, the creepage distance between the first connection part and the housing can be increased, reducing the possibility of short circuit between the first connection part and the housing.

[0017] In some embodiments, a surface of the shell facing the electrode lug of the electrode assembly has a convex portion, and the second insulating layer is disposed between a side wall of the convex portion and the first connecting portion.

[0018] The second insulating layer can reduce the possibility of the first connecting portion being charged due to contact with the side wall of the protrusion, improve the insulation performance of the battery cell, and thus improve the reliability of the battery cell.

[0019] In some embodiments, the connecting member includes a second connecting portion, the second connecting portion is bent relative to the first connecting portion, and the second connecting portion is connected to the electrode terminal.

[0020] The second connection portion can make the position of the electrode terminal more flexible, thereby making the internal structure arrangement of the battery cell more flexible.

[0021] In some embodiments, the first insulating portion includes a third insulating layer, and at least a portion of a surface of the second connecting portion that faces away from the electrode assembly is provided with the third insulating layer.

[0022] The third insulating layer can play an insulating role between the second connecting portion and the shell of the battery cell, reduce the possibility that the second connecting portion guides electrical energy to the shell of the battery cell, and improve the insulation performance of the battery cell.

[0023] In some embodiments, the outer shell includes an end cap and a shell, the end cap covers the opening of the shell; the battery cell includes: an insulating component, at least a portion of the insulating component is arranged between the shell and the connecting component, and at least a portion of the third insulating layer is arranged between the second connecting portion and the insulating component.

[0024] The third insulating layer can further play an insulating role between the connecting member and the insulating member, increase the insulating effect between the second connecting portion and the housing, and thus improve the reliability of the battery cell.

[0025] In some embodiments, the insulating member includes a first groove, and at least a portion of the third insulating layer is received in the first groove.

[0026] The third insulating layer can provide insulation between the connecting member and the shell, increase the creepage distance between the shell and the connecting member, reduce the possibility of the connecting member and the shell being connected due to polarization of the insulating member, and improve the reliability of the battery cell. At the same time, the first groove can reduce the space occupied by the third insulating layer and improve the energy density.

[0027] In some embodiments, the second connecting portion has a second surface, which connects the surface of the second connecting portion facing the electrode assembly and the surface of the second connecting portion facing away from the electrode assembly; the first insulating portion includes a fourth insulating layer, which covers at least a portion of the second surface.

[0028] The fourth insulating layer can cover as much of the insulating structure as possible on the surface of the second connecting portion, thereby improving the insulating performance of the second connecting portion and improving the reliability of the battery cell.

[0029] In some embodiments, a third insulating portion is disposed on at least a portion of the surface of the second connecting portion that faces the electrode assembly.

[0030] The third insulating part can provide insulation for the second connecting part on the side of the second connecting part facing the electrode assembly, thereby reducing the possibility that the surface of the electrode assembly facing the second connecting part contacts the second connecting part and becomes conductive.

[0031] In some embodiments, the fourth insulating layer is connected to at least one of the third insulating layer and the third insulating portion.

[0032] This can not only improve the insulation performance at the corners between different surfaces of the second connection part, but also increase the adhesion of the third insulation layer, the fourth insulation layer and the third insulation part on the surface of the second connection part, improve the insulation performance of the corresponding part on the second connection part, and thus improve the reliability of the battery cell. When the fourth insulation layer is connected to the third insulation layer and the third insulation part, the creepage distance between the second connection part and the shell can be increased, and the possibility of conduction between the second connection part and the shell can be reduced.

[0033] In some embodiments, the connecting member includes a first connecting portion, a second connecting portion and a third connecting portion, the first connecting portion is connected to the electrode assembly, the second connecting portion is connected to the electrode terminal, and the third connecting portion is bent and connects the first connecting portion and the second connecting portion.

[0034] The third connection portion can connect the first connection portion and the second connection portion extending in different directions, so that the electrode assembly and the battery cell respectively located on two intersecting planes can be electrically connected, thereby improving the flexibility of the internal structure arrangement of the battery cell.

[0035] In some embodiments, the first insulating portion includes a fifth insulating layer, and at least a portion of a surface of the third connecting portion that is away from the electrode assembly is provided with the fifth insulating layer.

[0036] The fifth insulating layer can provide insulation for the connecting member on the side of the third connecting portion facing the shell, thereby achieving insulation between the third connecting portion and the shell and reducing the possibility of the shell being charged.

[0037] In some embodiments, the third connecting portion has a third surface, which connects the surface of the third connecting portion facing the electrode assembly and the surface of the third connecting portion facing away from the electrode assembly; the first insulating portion includes a sixth insulating layer, and the sixth insulating layer is disposed on at least a portion of the third surface.

[0038] The sixth insulating layer can cover as much of the insulating structure as possible on the surface of the third connecting portion facing the outer shell of the battery cell, which can improve the insulating performance of the third connecting portion and the reliability of the battery cell.

[0039] In some embodiments, a fourth insulating portion is disposed on at least a portion of the surface of the third connecting portion facing the electrode assembly.

[0040] The fourth insulating portion can provide insulation for the surface of the third connecting portion facing the electrode assembly, so as to reduce the possibility of electrical connection between the electrode assembly and the third connecting portion.

[0041] In some embodiments, the sixth insulating layer is connected to at least one of the fifth insulating layer and the fourth insulating portion.

[0042] This not only improves the insulation performance at the corners between different surfaces of the third connecting part, but also increases the adhesion of the fifth insulating layer, the sixth insulating layer and the fourth insulating part on the surface of the third connecting part, improves the insulation performance of the corresponding parts on the third connecting part, thereby improving the reliability of the battery cell.

[0043] In some embodiments, a second insulating portion is provided on at least a portion of the surface of the first connecting portion facing the electrode assembly, a third insulating portion is provided on at least a portion of the surface of the second connecting portion facing the electrode assembly, and a fourth insulating portion is provided on at least a portion of the surface of the third connecting portion facing the electrode assembly, and the first insulating portion, the second insulating portion, the third insulating portion and the fourth insulating portion are integrally formed.

[0044] On the one hand, this can improve the adhesion of the first insulating part, the second insulating part, the third insulating part and the fourth insulating part on the connecting member, reduce the connection gap between the insulating parts in different regions on the connecting member, and improve the connection strength between the insulating parts in different regions on the connecting member. On the other hand, the first insulating part, the second insulating part, the third insulating part and the fourth insulating part can be integrally formed by injection molding or the like, thereby improving assembly efficiency.

[0045] In some embodiments, the housing includes an end cap and a shell, the end cap covers an opening of the shell, and the electrode terminal is disposed on the shell.

[0046] Providing the electrode terminal on the shell is beneficial to the integration of the electrode terminal and the shell, and is beneficial to improving the stability of the electrode terminal on the shell.

[0047] In some embodiments, the shell includes a first wall and a second wall adjacent to each other, the electrode terminal is disposed on the first wall, and a pole ear is disposed on a side of the electrode assembly facing the second wall.

[0048] This structure can make the positions of the electrode terminals and the tabs more flexible, and can be set according to different needs. At the same time, the bending shape of the connecting member is also conducive to the electrical connection of the electrode terminals and the tabs at different positions, making the internal structure arrangement of the battery cell more flexible.

[0049] In some embodiments, the end cap is connected to the first wall and to the second wall, the projection area of ​​the end cap in a direction perpendicular to the thickness of the end cap is larger than the projection area of ​​the first wall in a direction perpendicular to the thickness of the first wall, and the projection area of ​​the end cap in a direction perpendicular to the thickness of the end cap is larger than the projection area of ​​the second wall in a direction perpendicular to the thickness of the second wall.

[0050] When the area of ​​the end cover is large, the connecting member is connected to the electrode terminal at the portion corresponding to the first wall and to the electrode assembly at the portion corresponding to the second wall. In this case, the portion of the connecting member that may contact the end cover is smaller, and insulation between the connecting member and the end cover can be achieved through fewer insulating structures.

[0051] In some embodiments, the melting point of the first insulating portion is greater than or equal to 100°C.

[0052] In this way, the influence of the welding process between the connecting member and the electrode assembly on the first insulating part can be effectively reduced, thereby achieving good insulation between the first insulating part and the first connecting part and improving the reliability of the battery cell.

[0053] In a second aspect, a battery is provided, comprising the battery cell described in any of the above embodiments.

[0054] In a third aspect, an electrical device is provided, comprising the battery cell described in any one of the above embodiments or the battery described in any one of the above embodiments, wherein the battery cell or the battery is used to provide electrical energy to the electrical device.

[0055] In a fourth aspect, an energy storage device is provided, comprising the battery cell described in any one of the above embodiments or the battery described in any one of the above embodiments.

[0056] In a fifth aspect, a method for preparing a battery cell is provided, comprising: setting a first insulating portion on the surface of a connecting member; connecting one end of the connecting member to an electrode terminal provided on a shell and positioning the first insulating portion between the shell and the connecting member; and connecting the other end of the connecting member to an electrode assembly.

[0057] By providing a first insulating portion on the surface of the connecting member before the connecting member is connected to the electrode terminal and to the electrode assembly, the method for preparing a battery cell provided in an embodiment of the present application can reduce the difficulty of providing the first insulating portion between the connecting member and the outer shell. At the same time, the first insulating portion can provide better insulation performance between the connecting member and the outer shell, thereby improving the reliability of the battery cell.

[0058] In some embodiments, the connecting member includes a first connecting portion, a second connecting portion, and a third connecting portion, the first connecting portion is connected to the electrode assembly, the second connecting portion is connected to the electrode terminal, and the third connecting portion connects the first connecting portion and the second connecting portion.

[0059] The third connection portion can enable the electrode assembly and the battery cell respectively located on two intersecting planes to be electrically connected, thereby improving the flexibility of the internal structure arrangement of the battery cell.

[0060] In some embodiments, the method includes: forming the first insulating part, the second insulating part, the third insulating part and the fourth insulating part on the surface of the connecting member in an integrated manner, and making the second insulating part located between the electrode assembly and the first connecting part, the third insulating part located between the electrode assembly and the second connecting part, and the fourth insulating part located between the electrode assembly and the third connecting part.

[0061] In this way, when the connecting member is in a state of being assembled, insulation between the surface of the connecting member facing the electrode assembly and the electrode assembly can be achieved, thereby improving the insulation performance of the battery cell.

[0062] In some embodiments, the outer shell includes an end cap and a shell, and the method includes: when one end of the connecting member is connected to an electrode terminal provided on the outer shell and the first insulating portion is located between the outer shell and the connecting member, and the other end of the connecting member is connected to the electrode assembly, the end cap is closed over the opening of the shell.

[0063] The electrode assembly can be placed into the accommodating space inside the shell through the opening of the shell, and the end cover can be covered with the opening of the shell. Specifically, the connection between the end cover and the shell can be sealed by welding or the like, so that the outer shell formed by the end cover and the shell is as sealed as possible, which is beneficial to improving the reliability of the battery cell.

[0064] In some embodiments, the shell includes a side wall and a bottom wall, the bottom wall is opposite to the opening, and connecting one end of the connecting member to an electrode terminal provided on the shell and positioning the first insulating portion between the shell and the connecting member includes: connecting one end of the connecting member to an electrode terminal provided on the shell and positioning the first insulating portion between the side wall and the connecting member.

[0065] In this way, the first insulating part can provide a better insulation effect inside the battery cell, thereby improving the reliability of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without paying creative work.

[0067] Figure 1 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0068] Figure 2 It is a schematic diagram of the structure of a battery provided in an embodiment of the present application.

[0069] Figure 3 It is a schematic diagram of the structure of a battery cell provided in an embodiment of the present application.

[0070] Figure 4 yes Figure 3 Schematic diagram of the cross-sectional structure of the battery cell along the AA direction.

[0071] Figure 5 yes Figure 4 Schematic diagram of the enlarged structure of the T part in the middle.

[0072] Figure 6 It is a structural schematic diagram of a connecting component provided in an embodiment of the present application.

[0073] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure of the structure along the BB direction.

[0074] Figure 8 yes Figure 6 Schematic diagram of the structure in another perspective.

[0075] Fig. 9 It is a structural schematic diagram of another connecting component provided in an embodiment of the present application.

[0076] Fig.10 yes Figure 5The enlarged structural schematic diagram of part D and the structural schematic diagram of part D without the second insulating layer.

[0077] Fig.11 yes Figure 8 Schematic diagram of the cross-sectional structure of the structure along the CC direction.

[0078] Fig.12 yes Fig. 9 Schematic diagram of the cross-sectional structure of the structure along the FF direction.

[0079] Fig.13 yes Figure 5 Schematic diagram of the enlarged structure of part G in the middle.

[0080] Fig.14 yes Figure 7 Schematic diagram of the enlarged structure of part E.

[0081] Fig.15 This is a method for preparing a battery cell provided in an embodiment of the present application.

[0082] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0083] The following detailed description and drawings of the embodiments of the present application are used to illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0084] In the description of the present application, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicating the orientation or positional relationship, are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not strictly perpendicular, but within the tolerance range. "Parallel" is not strictly parallel, but within the tolerance range. All technical and scientific terms used in the present application have the same meaning as those generally understood by technicians in the technical field of the present application; the terms used in the present application and in the specification of the application are only for the purpose of describing specific embodiments, and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0085] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0086] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0087] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist, and B exists. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0088] The term "multiple" as used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple sheets" refers to more than two sheets (including two sheets).

[0089] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0090] In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, lithium metal batteries or magnesium-ion batteries, etc., and the embodiments of the present application do not limit this. Battery cells may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present application do not limit this.

[0091] 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. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0092] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as the positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. The negative electrode collector not coated with the negative electrode active material layer serves as the negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, lithium metal or lithium alloy, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. The material of the isolation film may be polypropylene (PP) or polyethylene (PE), etc. In addition, the electrode assembly in the embodiment of the present application includes but is not limited to a winding structure or a laminated structure.

[0093] Insulation areas are usually set in battery cells, especially in the parts where electrical connections are made inside the battery cells. It is even more necessary to reasonably set insulation areas to reduce the possibility of internal short circuits in the battery cells or charging of the outer shell. For example, the connecting member can achieve electrical connection between the electrode lugs and the electrode terminals of the electrode assembly, and the part where the connecting member contacts the outer shell of the battery cell needs to be affixed with insulating tape to achieve insulation between the connecting member and the outer shell, reducing the possibility of charging of the outer shell of the battery cell.

[0094] However, with the development of the manufacturing process of battery cells, the preparation of battery cells is increasingly tending towards high integration. In one manufacturing process of battery cells, the connecting components of the battery cells are pre-connected to the outer shell of the battery cells. In the subsequent assembly process, there is hardly enough operating space between the connecting components and the outer shell to affix insulating tape to the connecting components. The connecting components can easily conduct the electrical energy generated by the electrode assembly to the outer shell, causing the outer shell of the battery cell to be charged, thus affecting the reliability of the battery cell.

[0095] In view of this, an embodiment of the present application provides a battery cell, in which at least a portion of the surface of the connecting member of the battery cell facing the outer shell is provided with a first insulating portion. Even if the connecting member is pre-connected with the outer shell of the battery cell, when the battery cell is assembled, the first insulating portion can also achieve insulation between the connecting member and the outer shell, thereby reducing the possibility of the outer shell being charged, thereby improving the reliability of the battery cell.

[0096] The technical solutions described in the embodiments of the present application are applicable to various battery-powered electrical equipment. Electrical equipment may be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may be fuel vehicles, gas vehicles, or new energy vehicles, and new energy vehicles may be 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 include but are not limited to the above-mentioned electrical equipment.

[0097] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0098] like Figure 1As shown, it is a structural schematic diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 90, a controller 80 and a battery 10 may be arranged inside the vehicle 1. The controller 80 is used to control the battery 10 to supply power to the motor 90. For example, a battery 10 may be arranged at the bottom, front or rear of the vehicle 1. The battery 10 may be used to supply power to the vehicle 1. For example, the battery 10 may be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1. In another embodiment of the present application, the battery 10 may not only be used as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0099] In order to meet different power requirements, the battery may include multiple battery cells, wherein the multiple battery cells may be connected in series, in parallel, or in a hybrid connection, wherein the hybrid connection refers to a mixture of series and parallel connections. The battery may also be referred to as a battery pack. Optionally, multiple battery cells may be connected in series, in parallel, or in a hybrid connection to form a battery module, and multiple battery modules may be connected in series, in parallel, or in a hybrid connection to form a battery. In other words, multiple battery cells may be directly connected to form a battery, or may be first connected to form a battery module, and then the battery module may be connected to form a battery.

[0100] For example, Figure 2 The schematic diagram of the structure of a battery 10 according to an embodiment of the present application is shown. The battery 10 may include at least one battery module 200. The battery module 200 includes a plurality of battery cells 20. The battery 10 may also include a box 11, the inside of the box 11 is a hollow structure, and the plurality of battery cells 20 are accommodated in the box 11. Figure 2 A possible implementation of the box 11 of the embodiment of the present application is shown, such as Figure 2 As shown, the box body 11 may include two parts, which are respectively referred to as a first part 111 and a second part 112, and the first part 111 and the second part 112 are buckled together. The shapes of the first part 111 and the second part 112 may be determined according to the shape of the battery module 200 combination, and at least one of the first part 111 and the second part 112 has an opening. For example, Figure 2 As shown, the first part 111 and the second part 112 can both be hollow rectangular parallelepipeds and each has only one open face, the opening of the first part 111 and the opening of the second part 112 are arranged opposite to each other, and the first part 111 and the second part 112 are interlocked to form a box body 11 with a closed chamber.

[0101] For example, different from Figure 2As shown, only one of the first part 111 and the second part 112 may be a hollow cuboid with an opening, while the other may be in the shape of a plate to cover the opening. For example, here, the second part 112 is a hollow cuboid with only one face as an opening face, and the first part 111 is in the shape of a plate. Then, the first part 111 covers the opening of the second part 112 to form a box 11 with a closed chamber, which can be used to accommodate multiple battery cells 20. Multiple battery cells 20 are connected in parallel, in series, or in a mixed combination and placed in the box 11 formed by the first part 111 and the second part 112 being buckled together.

[0102] Optionally, the battery 10 may also include other structures, which are not described one by one here. For example, the battery 10 may also include a busbar component, which is used to realize electrical connection between multiple battery cells 20, such as parallel connection, series connection, or mixed connection. Specifically, the busbar component can realize electrical connection between the battery cells 20 by connecting the electrode terminals of the battery cells 20. Further, the busbar component can be fixed to the electrode terminals of the battery cells 20 by welding. The electrical energy of multiple battery cells 20 can be further led out through the conductive structure through the box body 11.

[0103] According to different power requirements, the number of battery cells 20 in the battery module 200 can be set to any value. Multiple battery cells 20 can be connected in series, parallel or mixed to achieve a larger capacity or power. Since the number of battery cells 20 included in each battery 10 may be large, in order to facilitate installation, the battery cells 20 are grouped and each group of battery cells 20 constitutes a battery module 200. The number of battery cells 20 included in the battery module 200 is not limited and can be set according to requirements. The battery 10 may include multiple battery modules 200, which can be connected in series, parallel or mixed.

[0104] Figure 3 A battery cell 20 provided in an embodiment of the present application is shown. Figure 4 yes Figure 3 A cross-sectional view of a portion of the structure of the battery cell 20 along the AA direction, Figure 5 yes Figure 4 The enlarged structural diagram of the T part in FIG. Figures 3 to 5 As shown, the battery cell 20 includes a housing 21, an electrode assembly 22, an electrode terminal 23 and a connecting member 24. In the embodiment of the present application, the length of the battery cell may be in the range of 300 mm to 800 mm, and the height may be in the range of 50 mm to 250 mm.

[0105] The electrode assembly 22 is accommodated in the housing 21, and the electrode terminal 23 is disposed in the housing 21. The connecting member 24 is used to connect the electrode terminal 23 and the electrode assembly 22, and at least a portion of the surface of the connecting member 24 facing the housing 21 is provided with a first insulating portion 31.

[0106] The battery cell 20 may include an outer shell 21 and one or more electrode assemblies 22, wherein the outer shell 21 may have multiple walls. The outer shell 21 of the battery cell 20 may be determined according to the shape of the one or more electrode assemblies 22 after being combined. For example, the outer shell 21 may be a cuboid, a cube, or a cylinder. The outer shell 21 may include a shell 210 and an end cap 213. The shell 210 may be a hollow structure with an opening formed at least at one end, and the shape of the end cap 213 may be adapted to the shape of the shell 210. The end cap 213 is used to cover the opening of the shell 210 so that the outer shell 21 isolates the internal environment of the battery cell 20 from the external environment. If the shell 210 is a hollow structure with an opening formed at one end, the end cap 213 may be provided as one; otherwise, if the shell 210 is a hollow structure with openings formed at opposite ends, the end cap 213 may be provided as two, and the two end caps 213 respectively cover the openings at both ends of the shell 210. The shapes of the shell 210 and the end cap 213 cooperate with each other. For example, as Figure 3 As shown, the housing 210 may be a rectangular parallelepiped structure, and the end cap 213 may be a rectangular plate-shaped structure adapted to the housing 210. For ease of description, the present application takes the housing 21 as a rectangular parallelepiped as an example. The end cap 213 is connected to the housing 210 to form a closed cavity for accommodating the electrode assembly 22, and the housing 210 is filled with an electrolyte, such as an electrolyte.

[0107] The electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs. The electrode assembly 22 may be a cylinder, a cuboid, etc. If the electrode assembly 22 is a cylindrical structure, the housing 210 may also be a cylindrical structure. If the electrode assembly 22 is a cuboid structure, the housing 210 may also be a cuboid structure. For any electrode assembly 22, the electrode assembly 22 may include at least two tabs, and the at least two tabs may include at least one positive tab and at least one negative tab. The positive tab may be formed by stacking a portion of the positive electrode sheet that is not coated with the positive active material layer, and the negative tab may be formed by stacking a portion of the negative electrode sheet that is not coated with the negative active material layer.

[0108] The housing 21 may also be provided with an electrode terminal 23, which is used to electrically connect to the electrode assembly 22 to output the electrical energy of the battery cell 20. The battery cell 20 may include at least two electrode terminals 23, and in some embodiments, the two electrode terminals 23 may be a positive electrode terminal and a negative electrode terminal, respectively. The at least two electrode terminals 23 may be provided on the same wall or different walls of the battery cell 20, for example, Figure 3It is shown that only one electrode terminal 23 is arranged on one of the walls of the outer shell 21. In some embodiments, another electrode terminal 23 can be arranged on a wall opposite to the wall; in some embodiments, it can also be arranged on a wall intersecting with the wall; in some embodiments, it can also be arranged on the wall.

[0109] The connection member 24 may also be referred to as a current collecting member, and is disposed between the housing 21 and the electrode assembly 22, and is used to electrically connect the electrode assembly 22 and the electrode terminal 23. The positive electrode tabs of one or more electrode assemblies 22 are connected to the positive electrode terminal through one connection member 24, and the negative electrode tabs of one or more electrode assemblies 22 are connected to the negative electrode terminal through another connection member 24. The connection member 24 and the tabs may be connected by laser welding or ultrasonic welding.

[0110] The first insulating portion 31 is disposed between the connecting member 24 and the housing 21. Figure 4 and Figure 5 shown.

[0111] In some embodiments, a portion of the surface of the connecting member 24 facing the housing 21 is provided with a first insulating portion 31. Specifically, the surface of the connecting member 24 can be divided into a connection area and a non-connection area, the connection area includes an area where the connecting member 24 is connected to the electrode terminal 23 or the electrode assembly 22, and the non-connection area includes an area other than the connection area. On the surface of the connecting member 24 facing the housing 21, the connection area of ​​the connecting member 24 is connected to the electrode terminal 23, and at least part of the non-connection area is provided with a first insulating portion 31. For example, on the surface of the connecting member 24 facing the housing 21, the first insulating portion 31 can be provided in a portion of the non-connection area that is closer to the housing 21; for another example, on the surface of the connecting member 24 facing the housing 21, the non-connection area can be provided with the first insulating portion 31.

[0112] In some embodiments, the surface of the connection member 24 facing the housing 21 is provided with a first insulating portion 31. In this case, the connection member 24 may have a through hole arranged opposite to the electrode terminal 23, and the electrode terminal 23 may be electrically connected to the connection member 24 by connecting to the side wall of the through hole.

[0113] In the embodiment of the present application, the first insulating portion 31 can achieve insulation between the connecting member 24 and the housing 21, and can reduce the possibility of the housing 21 being charged through the electrical connection between the connecting member 24 and the electrode assembly 22 when the distance between the connecting member 24 and the housing 21 is small, thereby improving the reliability of the battery cell 20. On the other hand, when the connecting member 24 and the housing 21 are pre-assembled together, it is difficult to set the insulating component after the connecting member 24 and the housing 21 are pre-assembled. Therefore, the first insulating portion 31 can also reduce the difficulty of setting the insulating component between the connecting member 24 and the housing 21, thereby improving the processing efficiency of the battery cell 20.

[0114] According to some embodiments of the present application, the connecting member 24 includes a first connecting portion 241 connected to the electrode assembly 22 , and the first insulating portion 31 includes a first insulating layer 311 , which is disposed on a surface of the first connecting portion 241 facing away from the electrode assembly 22 .

[0115] like Figure 4 and Figure 5 As shown, the first connection portion 241 is connected to the electrode assembly 22. Specifically, in the thickness direction of the first connection portion 241, the surface of the first connection portion 241 facing the electrode assembly 22 is electrically connected to the electrode tab of the electrode assembly 22, and the surface of the first connection portion 241 facing away from the electrode assembly 22 is provided with a first insulating layer 311. In the embodiment of the present application, the thickness direction of the first connection portion 241 may refer to the width direction Y of the battery cell 20.

[0116] In the embodiment of the present application, the length direction X of the battery cell 20 refers to the direction indicated by the longest side of the battery cell 20, the thickness direction Z of the battery cell 20 refers to the direction indicated by the shortest side of the battery cell 20, and the width direction Y of the battery cell 20 refers to the direction indicated by the side of the battery cell 20 whose length is between the longest side and the shortest side of the battery cell 20. That is, the dimension of the battery cell 20 in the length direction X is greater than the dimension of the battery cell 20 in the width direction Y, and the dimension of the battery cell 20 in the width direction Y is greater than the dimension of the battery cell 20 in the thickness direction Z.

[0117] exist Figure 5 In the illustrated structure, the first connection portion 241 is disposed opposite to a wall of the housing 21 of the battery cell 20 , and the first insulating layer 311 is disposed between the wall and the first connection portion 241 .

[0118] In some embodiments, the wall opposite to the first connection portion 241 may be a side wall of the battery cell 20 . In this case, during assembly, it is difficult for there to be enough space between the side wall and the connecting member 24 for the connecting member 24 to adhere to the insulating structure. Therefore, the first insulating layer 311 may be pre-set on the surface of the connecting member 24 .

[0119] The distance between the first connection part 241 and the outer shell 21 of the battery cell 20 is relatively close. In the case where the first insulating layer 311 is not provided, the first connection part 241 and the outer shell 21 are easily in contact, so that the outer shell 21 is charged. Therefore, the first insulating layer 311 can achieve insulation between the connection member 24 and the outer shell 21, reduce the possibility of the outer shell 21 being charged, and thus improve the reliability of the battery cell 20.

[0120] According to some embodiments of the present application, a second insulating portion 32 is disposed on at least a portion of the surface of the first connecting portion 241 facing the electrode assembly 22 .

[0121] Figure 6 is a schematic structural diagram of a connecting member 24 provided in an embodiment of the present application, Figure 7 yes Figure 6 A cross-sectional view of the connecting member 24 along the BB direction, Figure 8 yes Figure 6 A schematic diagram of the structure in another perspective. Fig. 9 2 is a schematic diagram of another structure of the connecting member 24. Figures 6 to 9 As shown, at least a portion of the surface of the first connection portion 241 facing the electrode assembly 22 is provided with a second insulating portion 32 .

[0122] In some embodiments, the surface of the first connection portion 241 facing the electrode assembly 22 may include a portion connected to the electrode lug of the electrode assembly 22, that is, a connection area of ​​the first connection portion 241, and a portion not connected to the electrode lug of the electrode assembly 22, that is, a non-connection area of ​​the first connection portion 241, and at least a portion of the non-connection area of ​​the first connection portion 241 may be provided with a second insulating portion 32. This provides space for the electrical connection between the electrode assembly 22 and the connecting member 24, and also enables the insulation performance of the first connection portion 241 to be achieved in as large a range as possible.

[0123] The second insulating portion 32 can provide insulation for the connecting member 24 on the side of the first insulating portion 31 facing the electrode assembly 22 , thereby improving the insulation performance of the first connecting portion 241 of the connecting member 24 .

[0124] According to some embodiments of the present application, the second insulating portion 32 is arranged at the edge of the surface of the first connecting portion 241 facing the electrode assembly 22, and the portion of the surface of the first connecting portion 241 facing the electrode assembly 22 where the second insulating portion 32 is not arranged is connected to the electrode lug of the electrode assembly 22.

[0125] The edge of the first connection portion 241 facing the surface of the electrode assembly 22 may refer to the edge of the first connection portion 241 arranged in the thickness direction Z of the battery cell 20 and in the length direction X of the battery cell 20, and the second insulating portion 32 may be provided in a region of at least one edge of the first insulating portion 31. For example, Figure 8 As shown, the second insulating portion 32 may be provided only in a region of at least one edge of the first connecting portion 241 arranged along the length direction X of the battery cell 20. Fig. 9 As shown, the second insulating portion 32 may be disposed in all edge regions of the first connecting portion 241 .

[0126] In this way, the edge area of ​​the first connection portion 241 can be insulated and protected, thereby reducing the possibility that the edge area of ​​the first connection portion 241 contacts the housing 210 and causes the housing 210 to be charged.

[0127] According to some embodiments of the present application, the first connecting portion 241 has a first surface, which connects the surface of the first connecting portion 241 facing the electrode assembly 22 and the surface of the first connecting portion 241 facing away from the electrode assembly 22; the first insulating portion 31 includes a second insulating layer 312, and the second insulating layer 312 is arranged on at least a portion of the first surface.

[0128] The first connection portion 241 may be a plate having a certain thickness, and the first surface may refer to a surface between a surface of the first connection portion 241 facing the electrode assembly 22 and a surface of the first connection portion 241 facing away from the electrode assembly 22 that can reflect the thickness of the first connection portion 241. In some embodiments, the first surface may be perpendicular to the thickness direction Z of the battery cell 20, and in some embodiments, the first surface may also be perpendicular to the length direction X of the battery cell 20.

[0129] At least a portion of the first surface is provided with a second insulating layer 312, Figure 8 and Fig. 9 The illustrated embodiment shows a situation where the first surface is completely covered by the second insulating layer 312 . Figure 8 and Fig. 9 Only the second insulating layer 312 is shown, and the first surface is not shown. It can be understood that the surface of the first connecting portion 241 covered by the second insulating layer 312 is the first surface. In some embodiments, the second insulating layer 312 can be provided only on a portion of the first surface. For example, the second insulating layer 312 can be provided on a portion of the first surface that is easily in contact with the housing 210 or the end cover 213.

[0130] Providing the second insulating layer 312 on the first surface can make the surface of the first connection portion 241 facing the housing 21 of the battery cell 20 cover the insulating structure as much as possible, which can improve the insulation performance of the first connection portion 241 and improve the reliability of the battery cell 20.

[0131] According to some embodiments of the present application, the second insulating layer 312 is connected to at least one of the first insulating layer 311 and the second insulating portion 32 .

[0132] In some embodiments, the second insulating layer 312 may be connected to the first insulating layer 311, such as Figure 6 and Figure 7 As shown, the corner between the surface of the first connection portion 241 facing away from the electrode assembly 22 and the first surface can be insulated by the connection between the second insulating layer 312 and the first insulating layer 311 .

[0133] In some embodiments, the second insulating layer 312 may be connected to the second insulating portion 32, such as Figure 8 and Fig. 9 As shown, the surface of the first connection portion 241 facing the electrode assembly 22 and the corner of the first surface can be insulated by the connection between the second insulating layer 312 and the second insulating portion 32 .

[0134] In some embodiments, the second insulating layer 312 can be connected to the first insulating layer 311 and the second insulating portion 32 at the same time, so that the first insulating layer 311, the second insulating layer 312 and the second insulating portion 32 can be connected as a whole, forming a bending structure from the surface of the first connection portion 241 facing away from the electrode assembly 22 to the first surface, and then to the surface of the first connection portion 241 facing the electrode assembly 22. This can not only improve the insulation performance at the corner of the first connection portion 241, but also increase the adhesion of the first insulating layer 311, the second insulating layer 312 and the second insulating portion 32 on the surface of the first connection portion 241, improve the insulation performance of the corresponding part on the first connection portion 241, and thus improve the reliability of the battery cell 20.

[0135] This can not only improve the insulation performance at the corner of the first connection part 241, but also increase the adhesion of the first insulating layer 311, the second insulating layer 312 and the second insulating part 32 on the surface of the first connection part 241, improve the insulation performance of the corresponding part on the first connection part 241, and thus improve the reliability of the battery cell 20. When the second insulating layer 312 is connected to the first insulating layer 311 and the second insulating part 32, the creepage distance between the first connection part 241 and the housing 210 can be increased, reducing the possibility of the first connection part 241 and the short circuit.

[0136] According to some embodiments of the present application, the surface of the housing 21 facing the tab of the electrode assembly 22 has a protrusion 214 , and a second insulating layer 312 is disposed between a side wall 2141 of the protrusion 214 and the first connecting portion 241 .

[0137] like Figure 3 and Figure 4 As shown, the convex portion 214 protrudes from the surface of the outer shell 21 facing the inside of the battery cell 20 to the inside of the battery cell 20, and the side wall 2141 of the convex portion 214 is at a certain angle to the top wall of the convex portion 214. Specifically, the convex portion 214 can protrude from the surface of the shell 210 facing the pole ear of the electrode assembly 22. The convex portion 214 forms a recess on the surface of the shell 210 facing away from the inside of the battery cell 20, and the accommodation space formed by the bottom wall and the side wall of the recess can usually be used to accommodate the internal structure of the battery, such as a thermal management component. Inside the battery cell 20, the side wall 2141 of the convex portion 214 is relatively close to the first connecting portion 241. When the battery cell 20 is shaken by an external force, it is easy for the first connecting portion 241 to contact the convex portion 214, causing the shell 210 of the battery cell 20 to be charged.

[0138] The second insulating layer 312 is disposed between the side wall 2141 of the protrusion 214 and the first connection portion 241. Specifically, the second insulating layer 312 is disposed at a position where the first connection portion 241 is easily in contact with the protrusion 214. Figure 4 As shown, a second insulating layer 312 is disposed on a portion of the first surface of the first connection portion 241 that faces the side wall of the protrusion 214 .

[0139] The second insulating layer 312 can reduce the possibility of the first connection portion 241 being charged due to contact with the side wall 2141 of the protrusion 214 , improve the insulation performance of the battery cell 20 , and thus improve the reliability of the battery cell 20 .

[0140] According to some embodiments of the present application, the connection member 24 includes a second connection portion 242 , the second connection portion 242 is bent relative to the first connection portion 241 , and the second connection portion 242 is connected to the electrode terminal 23 .

[0141] like Figures 3 to 9 As shown, the second connection portion 242 is connected to the electrode terminal 23. In some embodiments, the surface of the second connection portion 242 facing the housing 21 may be connected to the electrode terminal 23. In some embodiments, the second connection portion 242 may have a through hole arranged opposite to the electrode terminal 23, and at least a portion of the electrode terminal 23 is accommodated in the through hole. Then, the electrode terminal 23 can realize electrical connection between the second connection portion 242 and the electrode terminal 23 through the side wall of the through hole and / or the surface of the second connection portion 242 around the through hole.

[0142] In some embodiments, the second connection portion 242 and the first connection portion 241 are located on different planes. For example, the plane where the second connection portion 242 is located may have a certain angle with the plane where the first connection portion 241 is located, and the first connection portion 241 and the second connection portion 242 form a bent shape as a whole.

[0143] The second connection portion 242 can make the location of the electrode terminal 23 more flexible, thereby making the internal structure arrangement of the battery cell 20 more flexible.

[0144] According to some embodiments of the present application, the first insulating portion 31 includes a third insulating layer 313 , and at least a portion of the surface of the second connecting portion 242 facing away from the electrode assembly 22 is provided with the third insulating layer 313 .

[0145] The second connection portion 242 may include a portion connected to the electrode terminal 23, i.e., a connection area of ​​the second connection portion 242, and a portion not connected to the electrode terminal 23, i.e., a non-connection area of ​​the second connection portion 242. At least a portion of the non-connection area of ​​the second connection portion 242 may be provided with an insulating structure.

[0146] In some embodiments, at least a portion of the surface of the second connection portion 242 facing away from the electrode assembly 22 is provided with a third insulating layer 313. Specifically, at least a portion of the non-connection area of ​​the surface of the second connection portion 242 facing away from the electrode assembly 22 may be provided with the third insulating layer 313. Figure 5 As shown, the third insulating layer 313 is disposed on a portion of the surface of the second connecting portion 242 away from the electrode assembly 22 , and is disposed opposite to a wall of the housing 210 of the battery cell 20 , such as the first wall 211 .

[0147] The third insulating layer 313 can play an insulating role between the second connection portion 242 and the shell 210 of the battery cell 20 , reduce the possibility that the second connection portion 242 guides electrical energy to the shell 210 of the battery cell 20 , and improve the insulation performance of the battery cell 20 .

[0148] According to some embodiments of the present application, the housing 21 includes an end cap 213 and a shell 210, and the end cap 213 covers the opening of the shell 210. The battery cell 20 also includes an insulating member 25, at least a portion of the insulating member 25 is disposed between the shell 210 and the connecting member 24, and at least a portion of the third insulating layer 313 is disposed between the second connecting portion 242 and the insulating member 25.

[0149] The outer shell 21 of the battery cell 20 may include a shell 210 and an end cap 213. The shell 210 may be a hollow structure with an opening formed at least at one end, and the shape of the end cap 213 may be compatible with the shape of the shell 210. The end cap 213 is used to cover the opening of the shell 210 so that the outer shell 21 can isolate the internal environment of the battery cell 20 from the external environment. If the shell 210 is a hollow structure with an opening formed at one end, one end cap 213 may be provided; differently, if the shell 210 is a hollow structure with openings formed at two opposite ends, two end caps 213 may be provided, and the two end caps 213 respectively cover the openings at both ends of the shell 210. The shapes of the shell 210 and the end cap 213 match each other, for example, Figure 3 As shown, the housing 210 may be a rectangular parallelepiped structure, and the end cap 213 may be a rectangular plate-shaped structure adapted to the housing 210. For ease of description, the present application takes the housing 21 as a rectangular parallelepiped as an example. The end cap 213 is connected to the housing 210 to form a closed cavity for accommodating the electrode assembly 22, and the housing 210 is filled with an electrolyte, such as an electrolyte.

[0150] The insulating member 25 is a structure inside the battery cell 20 for electrically isolating the outer shell 21 of the battery cell 20 from other structures inside the battery cell 20. For example, in the embodiment of the present application, the connecting member 24 is electrically connected to the electrode terminal 23, and the insulating member 25 is at least partially disposed between the housing 210 and the connecting member 24, and the insulating member 25 can achieve insulation between the outer shell 21 and the connecting member 24. At least a portion of the insulating member 25 can be disposed between the electrode terminal 23 and the outer shell 21 to achieve insulation between the electrode terminal 23 and the outer shell 21.

[0151] In the embodiments of the present application, Figure 5 As shown, at least a portion of the third insulating layer 313 is disposed between the second connection portion 242 and the insulating member 25. In some embodiments, when the projection of the insulating member 25 and the electrode terminal 23 in the length direction X perpendicular to the battery cell 20 covers the second connection portion 242, the third insulating layer 313 may be entirely disposed between the second connection portion 242 and the insulating member 25.

[0152] Accordingly, a certain accommodation space may be provided between the insulating member 25 and the connecting member 24 to accommodate the third insulating layer 313. For example, a groove may be provided at a position of the insulating member 25 opposite to the third insulating layer 313 to accommodate the second insulating layer 312; for another example, a groove may be provided at a position of the second connecting portion 242 opposite to the third insulating layer 313 to accommodate the third insulating layer 313; for another example, grooves may be provided at a position of the insulating member 25 opposite to the third insulating layer 313 and at a position of the second connecting portion 242 opposite to the third insulating layer 313, respectively, and the grooves of the two grooves together form an accommodation space for accommodating the third insulating layer 313.

[0153] The third insulating layer 313 can further play an insulating role between the connecting member 24 and the insulating member 25 , and increase the insulation effect between the second connecting portion 242 and the housing 21 , thereby improving the reliability of the battery cell 20 .

[0154] According to some embodiments of the present application, the insulating member 25 includes a first groove 251 , and at least a portion of the third insulating layer 313 is received in the first groove 251 .

[0155] like Figures 5 to 10 As shown, a first groove 251 can be set on the surface of the insulating member 25 facing the second connection part 242, the third insulating layer 313 extends along the surface of the second connection part 242, and the portion of the third insulating layer 313 set between the insulating member 25 and the second connection part 242 extends into the first groove 251.

[0156] In some embodiments, the thickness of the insulating member 25 is generally greater than the thickness of the second connection portion 242. Providing the first groove 251 on the insulating member 25 can reduce the impact on the structural strength of the insulating member 25 and the second connection portion 242. At the same time, the thickness of the second connection portion 242 can be made more uniform, thereby improving the conductive effect of the second connection portion 242.

[0157] The third insulating layer 313 is arranged between the connecting member 24 and the insulating member 25 to increase the creepage distance between the connecting member 24 and the inner wall of the outer shell 21. The creepage distance refers to the shortest path between two conductive components or between a conductive component and the protective interface of the equipment measured along the insulating surface. In this embodiment of the present application, the creepage distance between the second connecting portion 242 and the outer shell 21 refers to the shortest path between the second connecting portion 242 and the outer shell 21 that can be conducted through the insulating member 25.

[0158] Specifically, Fig.10 As shown, Fig.10 (a) shows a case where the third insulating layer 313 is not provided between the connecting member 24 and the insulating member 25. In this case, the creepage distance between the connecting member 24 and the wall of the housing 21 is the distance between the points MN; Fig.10 (b) shows the case where a third insulating layer 313 is provided between the connecting member 24 and the insulating member 25. In this case, the creepage distance between the connecting member 24 and the wall of the housing 21 is the distance of the broken line segment of the point PQ-M'-N. The distance of the broken line segment of the point PQ-M'-N is greater than the distance between the points MN. When the insulating member 25 is polarized and charged, the charged area on the insulating member 25 can be kept away from the inner wall of the housing 21, reducing the possibility of the housing 21 being charged.

[0159] The third insulating layer 313 can provide insulation performance between the connecting member 24 and the shell 21 while increasing the creepage distance on the insulating member 25 between the shell 21 and the connecting member 24, reducing the possibility of the insulating member 25 being polarized and causing conduction between the connecting member 24 and the shell 21, thereby improving the reliability of the battery cell 20.

[0160] The third insulating layer 313 can provide insulation between the connecting member 24 and the housing 21, while increasing the creepage distance between the housing 21 and the connecting member 24, reducing the possibility of the insulating member 25 being polarized and causing the connecting member 24 and the housing 21 to be conductive, thereby improving the reliability of the battery cell 20. At the same time, the first groove 251 can reduce the space occupied by the third insulating layer 313 and improve the energy density.

[0161] According to some embodiments of the present application, the second connecting portion 242 has a second surface 244, which connects the surface of the second connecting portion 242 facing the electrode assembly 22 and the surface of the second connecting portion 242 facing away from the electrode assembly 22; the first insulating portion 31 includes a fourth insulating layer 314, which covers at least a portion of the second surface 244.

[0162] The second connection portion 242 may be a plate having a certain thickness, and the second surface 244 may refer to a surface between the surface of the second connection portion 242 facing the electrode assembly 22 and the surface of the second connection portion 242 facing away from the electrode assembly 22 that can reflect the thickness of the second connection portion 242. In some embodiments, the second surface 244 may be perpendicular to the thickness direction Z of the battery cell 20, and in some embodiments, the second surface 244 may also be perpendicular to the width direction Y of the battery cell 20. For example, the second surface 244 may include an end surface of the second connection portion 242 in the width direction Y of the battery cell 20.

[0163] The fourth insulating layer 314 is disposed on at least a portion of the second surface 244 . For example, the fourth insulating layer 314 may be disposed on a portion of the second surface 244 that is easily in contact with the housing 210 or the end cover 213 . Figure 8 and Fig. 9 The illustrated example shows that only a portion of the second surface 244 is covered with the fourth insulating layer 314. In some embodiments, the second surface 244 may be entirely covered with the fourth insulating layer 314.

[0164] The fourth insulating layer 314 can cover as much of the insulating structure as possible on the surface of the second connection portion 242 , which can improve the insulation performance of the second connection portion 242 and improve the reliability of the battery cell 20 .

[0165] According to some embodiments of the present application, a third insulating portion 33 is disposed on at least a portion of the surface of the second connection portion 242 facing the electrode assembly 22 .

[0166] The third insulating portion 33 is used to provide insulation between the surface of the second connecting portion 242 facing the electrode assembly 22 and the electrode assembly 22 .

[0167] In some embodiments, considering that the side of the electrode assembly 22 facing the second connecting portion 242 has an isolation film that can achieve insulation, the third insulating portion 33 may not be provided on the portion of the surface of the second connecting portion 242 facing the electrode assembly 22 that is opposite to the isolation film of the electrode assembly 22. This allows the battery cell 20 to have a larger space inside for setting the electrode assembly 22.

[0168] In some embodiments, the end surface of the electrode assembly 22 facing the first connection portion 241 may contact the second connection portion 242. Specifically, when the battery cell 20 is subjected to external forces such as shaking or impact, the portion of the end surface close to the second connection portion 242 may contact the second connection portion 242 to generate an electrical connection, so that the third insulating portion 33 can achieve insulation between the electrode assembly 22 and the second connection portion 242.

[0169] The third insulating portion 33 can provide insulation for the second connecting portion 242 on the side of the second connecting portion 242 facing the electrode assembly 22 , thereby reducing the possibility that the surface of the electrode assembly 22 facing the second connecting portion 242 contacts the second connecting portion 242 and becomes conductive.

[0170] According to some embodiments of the present application, the fourth insulating layer 314 is connected to at least one of the third insulating layer 313 and the third insulating portion 33 .

[0171] In the embodiment of the present application, the third insulating layer 313 is arranged on the surface of the second connecting portion 242 facing away from the electrode assembly 22, the third insulating portion 33 is arranged on the surface of the second connecting portion 242 facing the electrode assembly 22, and the fourth insulating layer 314 is arranged on the second surface 244 on the second connecting portion 242. The fourth insulating layer 314 can be connected to the third insulating layer 313, or the fourth insulating layer 314 can be connected to the third insulating portion 33, or the fourth insulating layer 314 can be connected to the third insulating layer 313 and the third insulating portion 33 at the same time.

[0172] In some embodiments, the fourth insulating layer 314 may be connected to the third insulating layer 313. Figure 6 As shown, the corner between the surface of the second connection portion 242 facing away from the electrode assembly 22 and the second surface 244 can be insulated by connecting the second insulating layer 312 with the first insulating layer 311 .

[0173] In some embodiments, the fourth insulating layer 314 may be connected to the third insulating portion 33. Figure 8 and Fig. 9As shown, the corner between the surface of the second connection portion 242 facing the electrode assembly 22 and the second surface 244 can be insulated by the connection between the fourth insulating layer 314 and the third insulating portion 33 .

[0174] In some embodiments, the fourth insulating layer 314 can be connected to the third insulating layer 313 and the third insulating part 33 at the same time, so that the fourth insulating layer 314, the third insulating layer 313 and the third insulating part 33 can be connected as a whole to form a bending structure from the surface of the second connection part 242 facing away from the electrode assembly 22 to the second surface 244, and then to the surface of the second connection part 242 facing the electrode assembly 22. Furthermore, a structure that wraps around the second connection part 242 can also be formed, which can not only improve the insulation performance at the corners between different surfaces of the second connection part 242, but also increase the adhesion of the third insulating layer 313, the fourth insulating layer 314 and the third insulating part 33 on the surface of the second connection part 242, thereby improving the insulation performance of the corresponding parts on the second connection part 242, thereby improving the reliability of the battery cell 20.

[0175] In this way, not only can the insulation performance at the corners between different surfaces of the second connection part 242 be improved, but also the adhesion of the third insulating layer 313, the fourth insulating layer 314 and the third insulating part 33 on the surface of the second connection part 242 can be increased, and the insulation performance of the corresponding part on the second connection part 242 can be improved, thereby improving the reliability of the battery cell 20. When the fourth insulating layer 314 is connected to the third insulating layer 313 and the third insulating part 33, the creepage distance between the second connection part 242 and the housing 210 can be increased, and the possibility of the second connection part 242 and the housing 210 being conductive can be reduced.

[0176] According to some embodiments of the present application, the connecting member 24 includes a first connecting portion 241, a second connecting portion 242 and a third connecting portion 243, the first connecting portion 241 is connected to the electrode assembly 22, the second connecting portion 242 is connected to the electrode terminal 23, and the third connecting portion 243 is bent and connects the first connecting portion 241 and the second connecting portion 242.

[0177] like Figures 5 to 10 As shown, the first connection portion 241 and the second connection portion 242 can extend in different directions, and the connection member 24 is bent as a whole, and the first connection portion 241 and the second connection portion 242 can be connected by the third connection portion 243. In some embodiments, the third connection portion 243 can be a circular arc-shaped plate. Specifically, the third connection portion 243 is Figure 3 and Figure 4In some embodiments, the third connection portion 243 may also be a plate of other shapes, such as a flat plate, and form a certain angle with the first connection portion 241 and the second connection portion 242, respectively, so as to connect the first connection portion 241 and the second connection portion 242 extending in different directions.

[0178] The third connection portion 243 can connect the first connection portion 241 and the second connection portion 242 extending in different directions, so that the electrode assembly 22 and the battery cell 20 respectively located on two intersecting planes can be electrically connected, thereby improving the flexibility of the internal structure arrangement of the battery cell 20.

[0179] According to some embodiments of the present application, the first insulating portion 31 includes a fifth insulating layer 315 , and the fifth insulating layer 315 is disposed on at least a portion of the surface of the third connecting portion 243 facing away from the electrode assembly 22 .

[0180] like Figures 4 to 9 As shown, the fifth insulating layer 315 can extend along the surface of the third connecting portion 243 that is away from the electrode assembly 22. For example, if the cross-section of the third connecting portion 243 on the plane formed by the width direction Y and the length direction of the battery cell 20 is an arc shape, then the cross-section of the fifth insulating layer 315 on the same plane is also an arc shape.

[0181] In some embodiments, the fifth insulating layer 315 may be connected to the first insulating layer 311 and the third insulating layer 313. For example, the first insulating layer 311, the third insulating layer 313 and the fifth insulating layer 315 may be connected in an integrated manner. In this way, the insulating layers of different parts may be covered on the surface of the connecting member 24 in a relatively tight manner, reducing the possibility of gaps between the insulating layers of different parts and improving the insulating performance of the connecting member 24.

[0182] The fifth insulating layer 315 can provide insulation for the connecting member 24 on the side of the third connecting portion 243 facing the outer shell 21 , thereby achieving insulation between the third connecting portion 243 and the housing 210 , and reducing the possibility of the outer shell 21 being charged.

[0183] According to some embodiments of the present application, the third connecting portion 243 has a third surface, and the third surface connects the surface of the third connecting portion 243 facing the electrode assembly 22 and the surface of the third connecting portion 243 away from the electrode assembly 22; the first insulating portion 31 includes a sixth insulating layer 316, and the sixth insulating layer 316 is arranged on at least a portion of the third surface.

[0184] The third connection portion 243 has a certain thickness, and the third surface may refer to a surface between the surface of the third connection portion 243 facing the electrode assembly 22 and the surface of the third connection portion 243 facing away from the electrode assembly 22 that can reflect the thickness of the third connection portion 243. In some embodiments, the third surface may be perpendicular to the thickness direction Z of the battery cell 20.

[0185] In the battery cell 20, the third surface is usually close to the end cover 213 of the battery cell 20 or the bottom wall of the housing 210, so the sixth insulating layer 316 may be provided on at least part of the third surface. Figures 6 to 9 The figure shows a situation where the third surface is completely covered by the sixth insulating layer 316 . Figures 6 to 9 Only the sixth insulating layer 316 is shown, and the third surface is not shown. It can be understood that the surface of the third connecting portion 243 covered by the sixth insulating layer 316 is the first surface. In some embodiments, the sixth insulating layer 316 may be provided only on a portion of the third surface. For example, the sixth insulating layer 316 may be provided on a portion of the third surface that is easily in contact with the housing 210 or the end cap 213.

[0186] The sixth insulating layer 316 can cover as much of the insulating structure as possible on the surface of the third connection portion 243 facing the housing 21 of the battery cell 20 , thereby improving the insulation performance of the third connection portion 243 and the reliability of the battery cell 20 .

[0187] According to some embodiments of the present application, a fourth insulating portion 34 is disposed on at least a portion of the surface of the third connecting portion 243 facing the electrode assembly 22 .

[0188] In the battery cell 20, the third connecting portion 243 does not need to be electrically connected to the electrode assembly 22 or the electrode terminal 23. However, during the actual use of the battery cell 20, the side of the third connecting portion 243 facing the electrode assembly 22 is easily in contact with the electrode assembly 22 and becomes charged. Therefore, a fourth insulating portion 34 is provided on at least a portion of the surface of the third connecting portion 243 facing the electrode assembly 22 to improve the insulation performance between the third connecting portion 243 and the electrode assembly 22.

[0189] The fourth insulating portion 34 can provide insulation for the surface of the third connecting portion 243 facing the electrode assembly 22 , so as to reduce the possibility of electrical connection between the electrode assembly 22 and the third connecting portion 243 .

[0190] According to some embodiments of the present application, the sixth insulating layer 316 is connected to at least one of the fifth insulating layer 315 and the fourth insulating portion 34 .

[0191] In the embodiment of the present application, the fifth insulating layer 315 is arranged on the surface of the third connecting portion 243 facing away from the electrode assembly 22, the fourth insulating portion 34 is arranged on the surface of the third connecting portion 243 facing the electrode assembly 22, and the sixth insulating layer 316 is arranged on the third surface on the third connecting portion 243. The sixth insulating layer 316 can be connected to the fifth insulating layer 315, or the sixth insulating layer 316 can be connected to the fourth insulating portion 34, or the sixth insulating layer 316 can be connected to the fifth insulating layer 315 and the fourth insulating portion 34 at the same time.

[0192] In some embodiments, the sixth insulating layer 316 may be connected to the fifth insulating layer 315. Figure 6 As shown, the corner between the surface of the third connection portion 243 facing away from the electrode assembly 22 and the third surface can be insulated by the connection between the sixth insulating layer 316 and the fifth insulating layer 315 .

[0193] In some embodiments, the sixth insulating layer 316 may be connected to the fourth insulating portion 34. Figure 8 and Fig. 9 As shown, the corner between the surface of the third connection portion 243 facing the electrode assembly 22 and the third surface can be insulated by the connection between the sixth insulating layer 316 and the fourth insulating portion 34 .

[0194] In some embodiments, the sixth insulating layer 316 can be connected to the fifth insulating layer 315 and the fourth insulating part 34 at the same time, so that the sixth insulating layer 316, the fifth insulating layer 315 and the fourth insulating part 34 can be connected as a whole to form a bending structure from the surface of the third connecting part 243 facing away from the electrode assembly 22 to the third surface, and then to the surface of the third connecting part 243 facing the electrode assembly 22. Furthermore, a structure that circles the third connecting part 243 can also be formed, which can not only improve the insulation performance at the corners between different surfaces of the third connecting part 243, but also increase the adhesion of the fifth insulating layer 315, the sixth insulating layer 316 and the fourth insulating part 34 on the surface of the third connecting part 243, improve the insulation performance of the corresponding parts on the third connecting part 243, and thus improve the reliability of the battery cell 20.

[0195] This not only improves the insulation performance at the corners between different surfaces of the third connection part 243, but also increases the adhesion of the fifth insulating layer 315, the sixth insulating layer 316 and the fourth insulating part 34 on the surface of the third connection part 243, and improves the insulation performance of the corresponding parts on the third connection part 243, thereby improving the reliability of the battery cell 20.

[0196] According to some embodiments of the present application, a second insulating portion 32 is provided on at least a portion of the surface of the first connecting portion 241 facing the electrode assembly 22, a third insulating portion 33 is provided on at least a portion of the surface of the second connecting portion 242 facing the electrode assembly 22, and a fourth insulating portion 34 is provided on at least a portion of the surface of the third connecting portion 243 facing the electrode assembly 22. The first insulating portion 31, the second insulating portion 32, the third insulating portion 33 and the fourth insulating portion 34 are integrally formed.

[0197] In some embodiments, the first insulating part 31, the second insulating part 32, the third insulating part 33 and the fourth insulating part 34 can be prepared by an injection molding process. Specifically, the first insulating part 31, the second insulating part 32, the third insulating part 33 and the fourth insulating part 34 can be formed on the surface of the connecting member 24 by the injection molding process, so that the connecting member 24, the first insulating part 31, the second insulating part 32, the third insulating part 33 and the fourth insulating part 34 are assembled as a whole with other components in the battery cell 20, without the need to stick the insulating part on the connecting member 24 after the connection between the connecting member 24 and the electrode assembly 22 or the electrode terminal 23 is completed.

[0198] On the one hand, this can improve the adhesion of the first insulating portion 31, the second insulating portion 32, the third insulating portion 33 and the fourth insulating portion 34 on the connecting member 24, reduce the connection gap between the insulating parts in different regions on the connecting member 24, and improve the connection strength between the insulating parts in different regions on the connecting member 24. On the other hand, the first insulating portion 31, the second insulating portion 32, the third insulating portion 33 and the fourth insulating portion 34 can be integrally formed by injection molding or the like, thereby improving assembly efficiency.

[0199] According to some embodiments of the present application, the housing 21 includes an end cap 213 and a shell 210 , the end cap 213 covers an opening of the shell 210 , and the electrode terminal 23 is disposed in the shell 210 .

[0200] like Figures 3 to 5As shown, the shell 210 of the battery cell 20 may be a hollow structure with an opening, and the shell 210 includes a plurality of walls, which enclose a receiving space. The shell 210 may have an opening at one end, and the battery cell 20 may include an end cap 213 for covering the opening; in some embodiments, the shell 210 may have openings at both ends, and the battery cell 20 may include two end caps 213, which are respectively used to cover the openings at both ends of the shell 210. The shape of the shell 210 may be determined according to the shape of one or more electrode assemblies 22 after being combined. For example, the shell 210 may be a hollow cuboid, a cube or a cylinder, and at least one surface of the shell 210 has an opening so that one or more electrode assemblies 22 can be placed in the shell 210. For example, when the shell 210 is a hollow cuboid or a cube, one of the planes of the shell 210 is an open surface, that is, the plane does not have a wall body so that the inside and outside of the shell 210 are connected. When the shell 210 is a hollow cylinder, the end surface of the shell 210 is an open surface, that is, the end surface has no wall so that the inside and outside of the shell 210 are connected. The end cover 213 can be a wall covering the opening and connected to the shell 210. The end cover 213 is sealed and connected to the shell 210 to form a closed cavity for accommodating the electrode assembly 22.

[0201] In some embodiments, the electrode terminal 23 may be disposed on the housing 210. Specifically, the positive electrode terminal and the negative electrode terminal may be disposed on the same wall or different walls of the housing 210. For example, Figure 3 It is shown that only one electrode terminal 23 is arranged on one of the walls of the outer shell 21. In some embodiments, another electrode terminal 23 can be arranged on a wall opposite to the wall; in some embodiments, it can also be arranged on a wall intersecting with the wall; in some embodiments, it can also be arranged on the wall.

[0202] The electrode terminal 23 is disposed on the housing 210 , which is beneficial to the integration of the electrode terminal 23 and the housing 210 , and is beneficial to improving the stability of the electrode terminal 23 on the housing 210 .

[0203] According to some embodiments of the present application, the shell 210 includes a first wall 211 and a second wall 212 adjacent to each other, the electrode terminal 23 is disposed on the first wall 211 , and a pole ear is disposed on one side of the electrode assembly 22 facing the second wall 212 .

[0204] like Figures 3 to 5As shown, the housing 210 may include a side wall and a bottom wall, and the bottom wall is opposite to the opening of the housing 210, that is, the bottom wall is opposite to the end cover 213. The area of ​​the bottom wall is greater than the area of ​​the first wall 211, and the area of ​​the bottom wall may also be greater than the area of ​​the second wall 212. In some embodiments, the first wall 211 and the second wall 212 may both be the side walls of the housing 210; in some embodiments, the first wall 211 and the second wall 212 may be the side wall and the bottom wall of the housing 210, respectively.

[0205] The first wall 211 is connected to the second wall 212, the electrode terminal 23 is disposed on the first wall 211, and is electrically connected to the connecting member 24, and the tabs of the electrode assembly 22 extend toward the second wall 212 and are electrically connected to the same connecting member 24. In other words, the connecting member 24 is bent inside the battery cell 20, and connects the electrode terminal 23 on the first wall 211 and the tabs toward the second wall 212.

[0206] This structure can make the positions of the electrode terminals 23 and the tabs more flexible, and can be set according to different requirements. At the same time, the bending shape of the connecting member 24 is also conducive to the electrical connection of the electrode terminals 23 and the tabs at different positions, making the internal structure arrangement of the battery cell 20 more flexible.

[0207] According to some embodiments of the present application, the end cover 213 is connected to the first wall 211 and to the second wall 212, the projection area of ​​the end cover 213 in a direction perpendicular to the thickness of the end cover 213 is larger than the projection area of ​​the first wall 211 in a direction perpendicular to the thickness of the first wall 211, and the projection area of ​​the end cover 213 in a direction perpendicular to the thickness of the end cover 213 is larger than the projection area of ​​the second wall 212 in a direction perpendicular to the thickness of the second wall 212.

[0208] The shell 210 of the battery cell 20 may include a first wall 211 and a second wall 212. In some embodiments, the side wall of the shell 210 includes the first wall 211 and the second wall 212, and the end cover 213 may be connected to the first wall 211 and the second wall 212 at the same time when the shell 210 is covered.

[0209] The end cover 213 can be approximately a flat plate-shaped structure, and the projection area of ​​the end cover 213 in a direction perpendicular to the thickness of the end cover 213 is the area of ​​the end cover 213; similarly, the first wall 211 and the second wall 212 can also be approximately a flat plate-shaped structure, and the projection area of ​​the first wall 211 in a direction perpendicular to the thickness of the end cover 213 is the area of ​​the first wall 211, and the projection area of ​​the second wall 212 in a direction perpendicular to the thickness of the end cover 213 is the area of ​​the second wall 212.

[0210] In some embodiments, the area of ​​the end cap 213 is greater than the area of ​​the first wall 211. Specifically, when the battery cell 20 includes a plurality of first walls 211, the area of ​​the end cap 213 may be greater than the area of ​​each first wall 211. In some embodiments, the area of ​​the end cap 213 is greater than the area of ​​the second wall 212. Specifically, when the battery cell 20 includes a plurality of second walls 212, the area of ​​the end cap 213 may be greater than the area of ​​each second wall 212. In some embodiments, the area of ​​the end cap 213 may be greater than both the area of ​​the first wall 211 and the area of ​​the second wall 212.

[0211] When the area of ​​the end cap 213 is large, the connecting member 24 is connected to the electrode terminal 23 at the portion corresponding to the first wall 211 and is connected to the electrode assembly 22 at the portion corresponding to the second wall 212. In this case, the portion of the connecting member 24 that may be in contact with the end cap 213 is relatively small, and insulation between the connecting member 24 and the end cap 213 can be achieved with fewer insulating structures.

[0212] According to some embodiments of the present application, the melting point of the first insulating part 31 is greater than or equal to 100° C.

[0213] The connecting member 24 and the pole ear of the electrode assembly 22 are usually connected by laser welding, so the insulating component on the surface of the connecting member 24 needs to be able to maintain its original state under the high temperature generated by welding to provide reliable insulation performance. In some embodiments, the melting point of the first insulating part 31 is greater than 100°C, which can effectively reduce the impact of the welding process of the connecting member 24 and the pole ear of the electrode assembly 22 on the first insulating part 31, thereby achieving good insulation between the first insulating part 31 and the first connecting part 241, and improving the reliability of the battery cell 20. In some embodiments, the material of the first insulating part 31 can be FPA, polypropylene (polypropylene, PP), etc.

[0214] In some embodiments, the melting point of the second insulating portion 32 may be greater than or equal to 100° C., for example, 100° C., 120° C., 200° C., 250° C., 300° C., 380° C., 400° C., 500° C., etc. The material of the second insulating portion 32 may specifically be soluble polytetrafluoroethylene (FPA), polypropylene (PP), polyvinyl chloride, etc.

[0215] According to some embodiments of the present application, a portion of the fourth insulating layer 314 located between the second connection portion 242 and the insulating member 25 has a size K in the width direction Y of the battery cell 20 , and K satisfies 1 mm≤K≤5 mm.

[0216] like Figures 5 to 10As shown, in the embodiment of the present application, the second connection portion 242 can extend in the width direction Y of the battery cell 20, and the size of the portion of the fourth insulating layer 314 located between the second connection portion 242 and the insulating member 25 in the width direction Y of the battery cell 20 is K. K satisfies 1mm≤K≤5mm, for example, K can be 1mm, 1.3mm, 2mm, 2.4mm, 3mm, 3.2mm, 4mm, 4.5mm, 5mm, etc. K satisfies the above numerical range, which can effectively increase the creepage distance between the second connection portion 242 and the housing 21, making the housing 21 less likely to be charged. At the same time, this can also reduce the possibility of the second insulating layer 312 interfering with the connection between the second connection portion 242 and the electrode terminal 23.

[0217] According to some embodiments of the present application, a distance L1 from the edge of the connecting member 24 to one end of the second insulating portion 32 disposed at the edge of the first connecting portion 241 away from the edge of the connecting member 24 satisfies 1 mm ≤ L1 ≤ 5 mm.

[0218] Fig.11 yes Figure 8 A schematic cross-sectional structure diagram of the connecting member 24, the first insulating portion 31 and the second insulating portion 32 along the CC direction, Fig.12 yes Fig. 9 The schematic cross-sectional structure diagram of the connecting member 24, the first insulating portion 31 and the second insulating portion 32 along the FF direction. Fig.11 and Fig.12 As shown, the portion of the second insulating portion 32 disposed at the edge of the first connecting portion 241 can extend from the edge of the first connecting portion 241 along the surface of the first connecting portion 241 facing the electrode assembly 22. In some embodiments, in a direction perpendicular to the edge of the first connecting portion 241, the size of the second connecting portion 242 is L1. L1 satisfies 1mm≤L1≤5mm, for example, L1 can be 1mm, 2mm, 2.2mm, 3mm, 3.6mm, 4mm, 4.2mm, 5mm, etc. L1 satisfying the above numerical range can effectively increase the adhesion of the first insulating portion 31 and the second insulating portion 32 on the connecting member 24, so that the first insulating portion 31 and the second insulating portion 32 are not easy to fall off from the connecting member 24, thereby providing better insulation performance for the battery cell 20.

[0219] According to some embodiments of the present application, in the thickness direction of the first connection portion 241 , a distance S is provided between an end of the fourth insulating layer 314 close to the electrode assembly 22 and a surface of the electrode assembly 22 facing the first connection portion 241 , and S satisfies 0.1 mm≤S≤1 mm.

[0220] The electrode assembly 22 is generally formed by winding or stacking a positive electrode sheet, a negative electrode sheet, and a separator, and the electrode tab extends from one surface of the electrode assembly 22 and protrudes from the surface.

[0221] The stacking direction of the positive electrode sheet and the negative electrode sheet is the thickness direction of the end cap 213. In some embodiments, the electrode assembly 22 is stacked by winding, and the wound electrode assembly 22 includes a stacking area and a bending area, and the stacking area and the bending area are sequentially connected to form a waist-shaped electrode assembly 22, and the arrangement direction of the electrode sheets in the stacking area is the stacking direction of the positive electrode sheet and the negative electrode sheet. In some embodiments, the electrode assembly 22 is stacked by stacking, for example, a continuous electrode sheet can be stacked with a plurality of cut electrode sheets, or a plurality of cut positive electrode sheets can be stacked with a plurality of cut negative electrode sheets, and the arrangement direction of the stacked electrode sheets is the stacking direction of the positive electrode sheet and the negative electrode sheet.

[0222] In the embodiment of the present application, the electrode tab of the electrode assembly 22 is connected to the first connection portion 241, and the surface of the electrode assembly 22 is opposite to the first connection portion 241. The distance between the end of the fourth insulating layer 314 close to the electrode assembly 22 and the surface of the electrode assembly 22 facing the first connection portion 241 is Fig.13 The S shown is Fig.13 for Figure 5 Schematic diagram of the enlarged structure of the G part in FIG. S satisfies 0.1 mm ≤ S ≤ 1 mm, for example, S can be 0.1 mm, 0.2 mm, 0.26 mm, 0.3 mm, 0.mm, 0.4 mm, 0.5 mm, 0.58 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.83 mm, 0.9 mm, 1 mm, etc. S satisfies the above numerical range to reduce the possibility of interference between the electrode assembly 22 and the second insulating portion 32, and at the same time, the third connecting portion 243 can be insulated and protected as much as possible.

[0223] According to some embodiments of the present application, the thickness of the first insulating portion 31 is H1, and H1 satisfies 0.2 mm≤H1≤0.8 mm.

[0224] Fig.14 yes Figure 7 The enlarged structural diagram of part E is shown in FIG. Fig.14 As shown, in some embodiments, the first insulating portion 31 may be a film with uniform thickness, and the thickness of the first insulating portion 31 may refer to Fig.12H1 in the embodiment. H1 satisfies 0.2 mm ≤ H1 ≤ 0.8 mm. For example, H1 may be 0.2 mm, 0.26 mm, 0.3 mm, 0.mm, 0.4 mm, 0.42 mm, 0.5 mm, 0.58 mm, 0.6 mm, 0.7 mm, 0.8 mm, etc. The thickness of the first insulating portion 31 within this range can make the first insulating portion 31 play a good insulating role between the first connecting portion 241 and the housing 21, and will not occupy too much internal space of the battery cell 20.

[0225] Similarly, the thickness of the second insulating portion 32 is H2, and H2 may satisfy 0.2 mm ≤ H2 ≤ 0.8 mm. For example, H2 may be 0.2 mm, 0.26 mm, 0.3 mm, 0.mm, 0.4 mm, 0.42 mm, 0.5 mm, 0.58 mm, 0.6 mm, 0.7 mm, 0.8 mm, etc. Similarly, the thickness of the third insulating portion 33 and the fourth insulating portion 34 may also be within the above value range.

[0226] An embodiment of the present application further provides a battery, comprising the battery cell 20 provided in any of the above embodiments.

[0227] An embodiment of the present application further provides an electrical device, comprising a battery provided by any of the above embodiments, and the battery is used to provide electrical energy to the electrical device.

[0228] An embodiment of the present application also provides an energy storage device, comprising a battery provided by any of the above embodiments.

[0229] The present application also provides a method 400 for preparing a battery cell 20, which is used to prepare the battery cell 20 provided in any of the above embodiments. Fig.15 As shown, the method 400 includes at least the following steps.

[0230] 410. Disposing a first insulating portion 31 on a surface of the connecting member 24;

[0231] 420. Connect one end of the connecting member 24 to the electrode terminal 23 provided on the housing 21 and locate the first insulating portion 31 between the housing 21 and the connecting member 24;

[0232] 430 . Connect the other end of the connecting member 24 to the electrode assembly 22 .

[0233] In the method for preparing the battery cell 20 , the first insulating portion 31 may be disposed on the surface of the connecting member 24 . Specifically, when the connecting member 24 is in an assembled state, the first insulating portion 31 may be disposed on at least a portion of the surface of the connecting member 24 facing the housing 21 .

[0234] The connecting member 24 provided with the first insulating portion 31 is connected to the electrode terminal 23. Specifically, the electrode terminal 23 is provided on the outer shell 21 of the battery cell 20, and the connecting member 24 is provided inside the battery cell 20. The surface of the connecting member 24 provided with the first insulating portion 31 is facing the outer shell 21 of the battery cell 20. When the connecting member 24 is in this state, one end of the connecting member 24 is connected to the electrode terminal 23. Then, the first insulating portion 31 is already provided between the connecting member 24 and the outer shell 21, and there is no need to provide an additional structure for insulation on the surface of the connecting member 24.

[0235] The other end of the connecting member 24 is connected to the electrode assembly 22, wherein the surface of the connecting member 24 connected to the electrode assembly 22 is provided with the first insulating portion 31 and one end of the connecting member 24 is connected to the electrode terminal 23. That is, when the connecting member 24 is connected to the electrode terminal 23 and the electrode assembly 22, the surface of the connecting member 24 facing the housing 21 of the battery cell 20 is already provided with the first insulating portion 31, and there is no need to provide a structure for insulation on the surface of the connecting member 24 after completing the connection with the electrode terminal 23 and the connection with the electrode assembly 22.

[0236] By setting a first insulating portion 31 on the surface of the connecting member 24 before the connecting member 24 is connected to the electrode terminal 23 and to the electrode assembly 22, the method for preparing the battery cell 20 provided in the embodiment of the present application can reduce the difficulty of setting the first insulating portion 31 between the connecting member 24 and the outer shell 21. At the same time, the first insulating portion 31 can provide better insulation performance between the connecting member 24 and the outer shell 21, thereby improving the reliability of the battery cell 20.

[0237] According to some embodiments of the present application, the connecting member 24 includes a first connecting portion 241, a second connecting portion 242 and a third connecting portion 243, the first connecting portion 241 is connected to the electrode assembly 22, the second connecting portion 242 is connected to the electrode terminal 23, and the third connecting portion 243 connects the first connecting portion 241 and the second connecting portion 242.

[0238] The first connection portion 241 and the second connection portion 242 may extend in different directions, and the connection member 24 is bent as a whole, so the first connection portion 241 and the second connection portion 242 may be connected via the third connection portion 243. The third connection portion 243 may enable the electrode assembly 22 and the battery cell 20 respectively located on two intersecting planes to be electrically connected, thereby improving the flexibility of the internal structure arrangement of the battery cell 20.

[0239] According to some embodiments of the present application, method 400 also includes: forming a first insulating part 31, a second insulating part 32, a third insulating part 33 and a fourth insulating part 34 on the surface of the connecting member 24 in an integrated manner, and making the second insulating part 32 located between the electrode assembly 22 and the first connecting part 241, the third insulating part 33 located between the electrode assembly 22 and the second connecting part 242, and the fourth insulating part 34 located between the electrode assembly 22 and the third connecting part 243.

[0240] The surface of the connecting member 24 may further be provided with a second insulating portion 32, a third insulating portion 33 and a fourth insulating portion 34. In the process of connecting the connecting member 24 to the electrode terminal 23 and connecting the connecting member 24 to the electrode assembly 22, the second insulating portion 32 is located between the electrode assembly 22 and the first connecting portion 241, the third insulating portion 33 is located between the electrode assembly 22 and the second connecting portion 242, and the third insulating portion 33 is located between the electrode assembly 22 and the second connecting portion 242. In the embodiment of the present application, the second insulating portion 32, the third insulating portion 33 and the fourth insulating portion 34 are all provided on the surface of the connecting member 24 facing the electrode assembly 22.

[0241] In this way, when the connection member 24 is in a fully assembled state, insulation can be achieved between the surface of the connection member 24 facing the electrode assembly 22 and the electrode assembly 22 , thereby improving the insulation performance of the battery cell 20 .

[0242] According to some embodiments of the present application, the housing 21 includes an end cap 213 and a housing 210. The method 400 further includes: when one end of the connecting member 24 is connected to the electrode terminal 23 disposed on the housing 21 and the first insulating portion 31 is located between the housing 21 and the connecting member 24, and the other end of the connecting member 24 is connected to the electrode assembly 22, the end cap 213 covers the opening of the housing 210.

[0243] The electrode assembly 22 can be placed into the accommodating space inside the shell 210 through the opening of the shell 210, and the end cover 213 covers the opening of the shell 210. Specifically, the connection between the end cover 213 and the shell 210 can be sealed by welding or the like, so that the outer shell 21 formed by the end cover 213 and the shell 210 is as sealed as possible, which is beneficial to improving the reliability of the battery cell 20.

[0244] According to some embodiments of the present application, the housing 210 includes a side wall and a bottom wall, and the bottom wall is opposite to the opening. Step 420 may specifically include: connecting one end of the connecting member 24 to the electrode terminal 23 disposed on the housing 21 and positioning the first insulating portion 31 between the side wall and the connecting member 24 .

[0245] In the embodiment of the present application, the surface area of ​​the connecting member 24 opposite to the side wall of the shell 210 is larger and the distance to the shell 210 is closer, so it is easier to contact the shell 210 and make the shell 210 charged. Therefore, in the process of connecting one end of the connecting member 24 to the electrode terminal 23 arranged on the outer shell 21, the first insulating part 31 is arranged between the side wall of the shell 210 and the connecting member 24, so that the first insulating part 31 can provide better insulation effect inside the battery cell 20, thereby improving the reliability of the battery cell 20.

[0246] The embodiment of the present application provides a battery cell 20, which includes a shell 21, an electrode assembly 22, an electrode terminal 23 and a connecting member 24. The shell 21 includes a shell 210 and an end cap 213, the shell 210 includes a first wall 211 and a second wall 212 intersecting each other, the electrode terminal 23 is arranged on the first wall 211, and the electrode tab of the electrode assembly 22 is located on the side of the electrode assembly 22 facing the second wall 212. The connecting member 24 includes a first connecting portion 241, a second connecting portion 242 and a third connecting portion 243, the first connecting portion 241 is connected to the electrode assembly 22 and is arranged between the electrode assembly 22 and the second wall 212, the second connecting portion 242 is connected to the electrode terminal 23 and is arranged between the first wall 211 and the electrode assembly 22, and the third connecting portion 243 connects the first connecting portion 241 and the second connecting portion 242.

[0247] At least a portion of the surface of the connection member 24 facing the housing 21 is provided with a first insulating portion 31 , which includes a first insulating layer 311 , a second insulating layer 312 , a third insulating layer 313 , a fourth insulating layer 314 , a fifth insulating layer 315 and a sixth insulating layer 316 .

[0248] The surface of the first connecting portion 241 facing away from the electrode assembly 22 is provided with a first insulating layer 311, the first surface is provided with a second insulating layer 312, and the surface facing the electrode assembly 22 is provided with a second insulating portion 32, wherein the first surface connects the surface of the first connecting portion 241 facing the electrode assembly 22 and the surface of the first connecting portion 241 facing away from the electrode assembly 22.

[0249] The surface of the second connecting portion 242 facing away from the electrode assembly 22 is provided with a third insulating layer 313, the second surface 244 is provided with a fourth insulating layer 314, and the surface facing the electrode assembly 22 is provided with a third insulating portion 33, wherein the second surface 244 connects the surface of the second connecting portion 242 facing the electrode assembly 22 with the surface of the second connecting portion 242 facing away from the electrode assembly 22.

[0250] The surface of the third connecting portion 243 facing away from the electrode assembly 22 is provided with a fifth insulating layer 315, the third surface is provided with a sixth insulating layer 316, and the surface facing the electrode assembly 22 is provided with a fourth insulating portion 34, wherein the third surface connects the surface of the third connecting portion 243 facing the electrode assembly 22 and the surface of the third connecting portion 243 facing away from the electrode assembly 22.

[0251] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A battery cell, characterized in that: include: shell; an electrode assembly, the electrode assembly being accommodated in the housing; an electrode terminal, the electrode terminal being disposed on the housing; A connecting member is used to connect the electrode terminal and the electrode assembly, and a first insulating portion is provided on at least a portion of the surface of the connecting member facing the shell.

2. The battery cell according to claim 1, characterized in that: The connecting member includes a first connecting portion connected to the electrode assembly, and the first insulating portion includes a first insulating layer disposed on a surface of the first connecting portion facing away from the electrode assembly.

3. The battery cell according to claim 2, characterized in that: A second insulating portion is disposed on at least a portion of the surface of the first connecting portion that faces the electrode assembly.

4. The battery cell according to claim 3, characterized in that: The second insulating portion is arranged at an edge of the surface of the first connecting portion facing the electrode assembly, and a portion of the surface of the first connecting portion facing the electrode assembly where the second insulating portion is not arranged is connected to a tab of the electrode assembly.

5. The battery cell according to claim 3 or 4, characterized in that: The first connecting portion has a first surface, and the first surface connects a surface of the first connecting portion facing the electrode assembly and a surface of the first connecting portion facing away from the electrode assembly; The first insulating portion includes a second insulating layer, and the second insulating layer is disposed on at least a portion of the first surface.

6. The battery cell according to claim 5, characterized in that: The second insulating layer is connected to at least one of the first insulating layer and the second insulating portion.

7. The battery cell according to claim 5 or 6, characterized in that: A surface of the housing facing the electrode tab of the electrode assembly has a convex portion, and the second insulating layer is disposed between a side wall of the convex portion and the first connecting portion.

8. The battery cell according to any one of claims 2 to 7, characterized in that: The connecting member includes a second connecting portion, the second connecting portion is bent relative to the first connecting portion, and the second connecting portion is connected to the electrode terminal.

9. The battery cell according to claim 8, characterized in that: The first insulating portion includes a third insulating layer, and at least a portion of a surface of the second connecting portion that faces away from the electrode assembly is provided with the third insulating layer.

10. The battery cell according to claim 9, characterized in that: The housing comprises an end cover and a shell, wherein the end cover covers an opening of the shell; The battery cell comprises: An insulating member, at least a portion of which is disposed between the shell and the connecting member, and at least a portion of the third insulating layer is disposed between the second connecting portion and the insulating member.

11. The battery cell according to claim 10, characterized in that: The insulating member includes a first groove, and at least a portion of the third insulating layer is received in the first groove.

12. The battery cell according to any one of claims 8 to 11, characterized in that: The second connecting portion has a second surface, and the second surface connects a surface of the second connecting portion facing the electrode assembly and a surface of the second connecting portion facing away from the electrode assembly; The first insulating portion includes a fourth insulating layer covering at least a portion of the second surface.

13. The battery cell according to any one of claims 8 to 12, characterized in that: A third insulating portion is disposed on at least a portion of the surface of the second connecting portion that faces the electrode assembly.

14. The battery cell according to claim 13, characterized in that: The fourth insulating layer is connected to at least one of the third insulating layer and the third insulating portion.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The connecting member includes a first connecting portion, a second connecting portion and a third connecting portion, the first connecting portion is connected to the electrode assembly, the second connecting portion is connected to the electrode terminal, and the third connecting portion is bent and connects the first connecting portion and the second connecting portion.

16. The battery cell according to claim 15, characterized in that: The first insulating portion includes a fifth insulating layer, and at least a portion of a surface of the third connecting portion that is away from the electrode assembly is provided with the fifth insulating layer.

17. The battery cell according to claim 15 or 16, characterized in that: The third connection portion has a third surface, and the third surface connects a surface of the third connection portion facing the electrode assembly and a surface of the third connection portion facing away from the electrode assembly; The first insulating portion includes a sixth insulating layer, and the sixth insulating layer is disposed on at least a portion of the third surface.

18. The battery cell according to any one of claims 15 to 17, characterized in that: A fourth insulating portion is disposed on at least a portion of the surface of the third connecting portion facing the electrode assembly.

19. The battery cell according to claim 18, characterized in that: The sixth insulating layer is connected to at least one of the fifth insulating layer and the fourth insulating portion.

20. The battery cell according to any one of claims 15 to 19, characterized in that: A second insulating portion is provided on at least a portion of the surface of the first connecting portion facing the electrode assembly, a third insulating portion is provided on at least a portion of the surface of the second connecting portion facing the electrode assembly, and a fourth insulating portion is provided on at least a portion of the surface of the third connecting portion facing the electrode assembly. The first insulating portion, the second insulating portion, the third insulating portion and the fourth insulating portion are integrally formed.

21. The battery cell according to any one of claims 1 to 20, characterized in that: The housing includes an end cover and a shell, the end cover covers an opening of the shell, and the electrode terminal is arranged on the shell.

22. The battery cell according to claim 21, characterized in that: The shell includes a first wall and a second wall adjacent to each other, the electrode terminal is arranged on the first wall, and a pole ear is arranged on a side of the electrode assembly facing the second wall.

23. The battery cell according to claim 22, characterized in that: The end cap is connected to the first wall and to the second wall, the projection area of ​​the end cap in a direction perpendicular to the thickness of the end cap is larger than the projection area of ​​the first wall in a direction perpendicular to the thickness of the first wall, and the projection area of ​​the end cap in a direction perpendicular to the thickness of the end cap is larger than the projection area of ​​the second wall in a direction perpendicular to the thickness of the second wall.

24. The battery cell according to any one of claims 1 to 23, characterized in that: The melting point of the first insulating portion is greater than or equal to 100° C.

25. A battery, characterized in that: include: A battery cell according to any one of claims 1 to 24.

26. An electrical device, characterized in that: include: The battery cell according to any one of claims 1 to 24 or the battery according to claim 25, wherein the battery cell or the battery is used to provide electrical energy to the electrical device.

27. An energy storage device, characterized in that: include: A battery cell according to any one of claims 1 to 24 or a battery according to claim 25.

28. A method for preparing a battery cell, characterized in that: include: Disposing a first insulating portion on a surface of the connecting member; Connecting one end of the connecting member to an electrode terminal disposed on the housing and positioning the first insulating portion between the housing and the connecting member; The other end of the connecting member is connected to the electrode assembly.

29. The method according to claim 28, characterized in that The connection member includes a first connection portion, a second connection portion, and a third connection portion, the first connection portion is connected to the electrode assembly, the second connection portion is connected to the electrode terminal, and the third connection portion connects the first connection portion and the second connection portion.

30. The method according to claim 29, characterized in that The method comprises: The first insulating part, the second insulating part, the third insulating part and the fourth insulating part are formed on the surface of the connecting member in an integrated manner, so that the second insulating part is located between the electrode assembly and the first connecting part, the third insulating part is located between the electrode assembly and the second connecting part, and the fourth insulating part is located between the electrode assembly and the third connecting part.

31. The method according to any one of claims 28 to 30, characterized in that The housing comprises an end cover and a shell, The method comprises: When one end of the connecting member is connected to the electrode terminal provided on the shell and the first insulating portion is located between the shell and the connecting member, and the other end of the connecting member is connected to the electrode assembly, the end cap covers the opening of the shell.

32. The method according to claim 31, characterized in that The housing comprises a side wall and a bottom wall, wherein the bottom wall is opposite to the opening. The step of connecting one end of the connecting member to an electrode terminal disposed on the housing and locating the first insulating portion between the housing and the connecting member comprises: One end of the connection member is connected to an electrode terminal provided on the housing, and the first insulating portion is located between the side wall and the connection member.

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