Battery cell and preparation method therefor, battery, electric device, and energy storage device

Abstract

Embodiments of the present application provide a battery cell and a preparation method therefor, a battery, an electric device, and an energy storage device, capable of improving the insulation performance of the interior of the battery cell. The battery cell comprises: a casing; an electrode assembly, the electrode assembly being accommodated in the casing; an electrode terminal, the electrode terminal being arranged on the casing; and a connecting member, the connecting member being used for connecting the electrode terminal and the electrode assembly, and at least part of the surface of the connecting member facing the casing being provided with a first insulating part.

Description

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

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202311434115.7, filed on October 31, 2023, entitled “Battery Cell and Preparation Method thereof, Battery, Electrical Device, Energy Storage Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] 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

[0004] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. In this context, electric vehicles, due to their energy-saving and environmentally friendly advantages, have become a crucial component of the industry's sustainable development. Battery technology, in turn, is a crucial factor in the development of electric vehicles.

[0005] An insulation 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 remains a problem that needs to be solved.

[0006] Summary of the Invention

[0007] 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.

[0008] 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 provided on at least a portion of the surface of the connecting member facing the shell.

[0009] In the embodiments of the present application, the first insulating portion provides insulation between the connecting member and the outer shell. This reduces the likelihood of the outer shell becoming electrically charged through the electrical connection between the connecting member and the electrode assembly when the distance between the connecting member and the outer shell is small, thereby improving the reliability of the battery cell. Furthermore, when the connecting member and the outer shell are pre-assembled, it is difficult to install insulating components afterward. Therefore, the first insulating portion also reduces the difficulty of installing insulating components between the connecting member and the outer shell, thereby improving the processing efficiency of the battery cell.

[0010] 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 disposed on a surface of the first connecting portion facing away from the electrode assembly.

[0011] The first connecting portion is relatively close to the outer shell of the battery cell. Without the first insulating layer, the first connecting portion and the outer shell are likely to come into contact, causing the outer shell to become electrically charged. Therefore, the first insulating layer insulates the connecting member from the outer shell, reducing the possibility of the outer shell becoming electrically charged, thereby improving the reliability of the battery cell.

[0012] 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.

[0013] 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.

[0014] In some embodiments, the second insulating portion is disposed on the edge of the surface of the first connecting portion facing the electrode assembly, and the portion of the surface of the first connecting portion facing the electrode assembly where the second insulating portion is not disposed is connected to the tab of the electrode assembly.

[0015] 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.

[0016] 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.

[0017] Providing a second insulating layer on the first surface allows the surface of the first connection portion facing the battery cell housing to cover as much of the insulating structure as possible, thereby improving the insulation performance of the first connection portion and the reliability of the battery cell.

[0018] In some embodiments, the second insulating layer is connected to at least one of the first insulating layer and the second insulating portion.

[0019] This not only improves the insulation performance at the corners of the first connecting portion, but also increases the adhesion of the first insulating layer, second insulating layer, and second insulating portion to the surface of the first connecting portion, improving the insulation performance of the corresponding portions of the first connecting portion, thereby enhancing the reliability of the battery cell. When the second insulating layer is connected to both the first insulating layer and the second insulating portion, the creepage distance between the first connecting portion and the housing is increased, reducing the possibility of a short circuit between the first connecting portion and the housing.

[0020] In some embodiments, a surface of the housing facing the tab of the electrode assembly has a convex portion, and the second insulating layer is provided between a side wall of the convex portion and the first connecting portion.

[0021] 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, thereby improving the insulation performance of the battery cell and thus improving the reliability of the battery cell.

[0022] 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.

[0023] The second connecting portion can make the position of the electrode terminal more flexible, thereby making the internal structure arrangement of the battery cell more flexible.

[0024] 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 facing away from the electrode assembly is provided with the third insulating layer.

[0025] 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.

[0026] In some embodiments, the outer shell includes an end cover and a shell, the end cover covers the opening of the shell; the battery cell includes: an insulating member, at least a portion of the insulating member is arranged between the shell and the connecting member, and at least a portion of the third insulating layer is arranged between the second connecting portion and the insulating member.

[0027] The third insulating layer can further play an insulating role between the connecting member and the insulating member, thereby increasing the insulation effect between the second connecting portion and the housing, thereby improving the reliability of the battery cell.

[0028] 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.

[0029] The third insulating layer provides insulation between the connecting member and the outer shell while increasing the creepage distance between the outer shell and the connecting member. This reduces the possibility of the insulating member being polarized and causing electrical conduction between the connecting member and the outer shell, thereby improving the reliability of the battery cell. Furthermore, the first groove reduces the space occupied by the third insulating layer, thereby increasing energy density.

[0030] 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.

[0031] The fourth insulating layer can cover the surface of the second connecting portion with as much of the insulating structure as possible, thereby improving the insulating performance of the second connecting portion and the reliability of the battery cell.

[0032] In some embodiments, a third insulating portion is provided on at least a portion of the surface of the second connecting portion facing the electrode assembly.

[0033] The third insulating portion can provide insulation for the second connecting portion on the side of the second connecting portion facing the electrode assembly, reducing the possibility that the surface of the electrode assembly facing the second connecting portion contacts the second connecting portion and becomes conductive.

[0034] In some embodiments, the fourth insulating layer is connected to at least one of the third insulating layer and the third insulating portion.

[0035] This not only improves the insulation performance at the corners between different surfaces of the second connecting portion, but also increases the adhesion of the third insulating layer, fourth insulating layer, and third insulating portion to the surface of the second connecting portion, improving the insulation performance of the corresponding portions of the second connecting portion, thereby enhancing the reliability of the battery cell. When the fourth insulating layer is connected to the third insulating layer and the third insulating portion, the creepage distance between the second connecting portion and the housing is increased, reducing the possibility of electrical conduction between the second connecting portion and the housing.

[0036] In some embodiments, the connecting member includes a first connecting portion, a second connecting portion, and a third connecting portion, wherein 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.

[0037] 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.

[0038] In some embodiments, the first insulating portion includes a fifth insulating layer, and at least a portion of the surface of the third connecting portion facing away from the electrode assembly is provided with the fifth insulating layer.

[0039] 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.

[0040] 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, which is arranged on at least a portion of the third surface.

[0041] 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, thereby improving the insulating performance of the third connecting portion and the reliability of the battery cell.

[0042] In some embodiments, a fourth insulating portion is provided on at least a portion of the surface of the third connecting portion facing the electrode assembly.

[0043] 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.

[0044] In some embodiments, the sixth insulating layer is connected to at least one of the fifth insulating layer and the fourth insulating portion.

[0045] 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, and thus improves the reliability of the battery cell.

[0046] 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. The first insulating portion, the second insulating portion, the third insulating portion and the fourth insulating portion are formed as one piece.

[0047] On the one hand, this can improve the adhesion of the first, second, third, and fourth insulating portions to the connecting member, reduce the connection gaps between insulating components in different areas of the connecting member, and improve the connection strength between insulating components in different areas of the connecting member. On the other hand, the first, second, third, and fourth insulating portions can be integrally formed through methods such as injection molding, improving assembly efficiency.

[0048] 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.

[0049] 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.

[0050] 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 tab is disposed on a side of the electrode assembly facing the second wall.

[0051] This structure allows for greater flexibility in the positioning of the electrode terminals and tabs, allowing them to be positioned according to varying needs. The curved shape of the connecting member also facilitates electrical connection between the electrode terminals and tabs at different locations, further flexibly arranging the internal structure of the battery cell.

[0052] In some embodiments, the end cap is connected to the first wall and to the second wall, the projected area of ​​the end cap in the direction perpendicular to the thickness of the end cap is larger than the projected area of ​​the first wall in the direction perpendicular to the thickness of the first wall, and the projected area of ​​the end cap in the direction perpendicular to the thickness of the end cap is larger than the projected area of ​​the second wall in the direction perpendicular to the thickness of the second wall.

[0053] When the area of ​​the end cover is large, the connecting member is connected to the electrode terminal at the part corresponding to the first wall and to the electrode assembly at the part corresponding to the second wall. Then, the part of the connecting member that may be in contact with the end cover is smaller, and insulation between the connecting member and the end cover can be achieved through fewer insulating structures.

[0054] In some embodiments, the melting point of the first insulating portion is greater than or equal to 100°C.

[0055] This can effectively reduce the impact of the welding process between the connecting member and the electrode assembly on the first insulating part, thereby achieving good insulation between the first insulating part and the first connecting part, and improving the reliability of the battery cell.

[0056] In a second aspect, a battery is provided, comprising the battery cell described in any one of the above embodiments.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] In some embodiments, the connecting member includes a first connecting portion, a second connecting portion, and a third connecting portion, wherein 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.

[0062] 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.

[0063] 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.

[0064] In this way, when the connecting member is in a fully assembled state, insulation can be achieved between the surface of the connecting member facing the electrode assembly and the electrode assembly, thereby improving the insulation performance of the battery cell.

[0065] 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 the electrode terminal provided on the outer shell and the first insulating part 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 covered with the opening of the shell.

[0066] 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 a sealed structure as much as possible, which is beneficial to improving the reliability of the battery cell.

[0067] 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 the electrode terminal provided on the shell and positioning the first insulating part between the shell and the connecting member includes: connecting one end of the connecting member to the electrode terminal provided on the shell and positioning the first insulating part between the side wall and the connecting member.

[0068] 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

[0069] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0070] FIG1 is a schematic structural diagram of a vehicle provided in an embodiment of the present application.

[0071] FIG2 is a schematic structural diagram of a battery provided in an embodiment of the present application.

[0072] FIG3 is a schematic structural diagram of a battery cell provided in an embodiment of the present application.

[0073] FIG4 is a schematic cross-sectional structural diagram of the battery cell along the AA direction in FIG3 .

[0074] FIG5 is an enlarged structural diagram of the T portion in FIG4 .

[0075] FIG6 is a schematic structural diagram of a connecting component provided in an embodiment of the present application.

[0076] FIG7 is a schematic cross-sectional view of the structure in FIG6 along the BB direction.

[0077] FIG8 is a schematic structural diagram of the structure in FIG6 from another perspective.

[0078] FIG9 is a schematic structural diagram of another connecting member provided in an embodiment of the present application.

[0079] FIG10 is an enlarged structural schematic diagram of portion D in FIG5 and a structural schematic diagram of portion D without the second insulating layer.

[0080] FIG11 is a schematic cross-sectional view of the structure in FIG8 along the CC direction.

[0081] FIG12 is a schematic diagram of the cross-sectional structure of the structure in FIG9 along the FF direction.

[0082] FIG13 is an enlarged structural diagram of portion G in FIG5 .

[0083] FIG14 is an enlarged structural diagram of portion E in FIG7 .

[0084] FIG15 is a method for preparing a battery cell provided in an embodiment of the present application.

[0085] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0086] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0087] In the description of this application, it should be noted that the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicating directions or positional relationships, are used solely for the purpose of facilitating the description of this application and simplifying the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limiting this application. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Perpendicular" does not mean perpendicular in the strict sense, but rather within the tolerance range. "Parallel" does not mean parallel in the strict sense, but rather within the tolerance range. All technical and scientific terms used in this application have the same meanings as those commonly understood by those skilled in the art to which this application belongs. The terms used in this application and in the specification of the application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including," "having," and any variations thereof in the specification and claims of this application and the accompanying drawings are intended to cover non-exclusive inclusions.

[0088] 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.

[0089] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0090] The term "and / or" in this application simply describes an association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists, A and B exist, and B exists. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0091] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0092] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0093] In this 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 this application do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0094] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. A battery generally includes a casing that encloses one or more battery cells. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0095] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive electrode collector. The uncoated positive electrode collector protrudes from the coated positive electrode collector, and the uncoated positive electrode collector serves as the positive electrode tab. For lithium-ion batteries, for example, the positive electrode current collector can be made of 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 current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative electrode collector. The uncoated negative electrode collector protrudes from the coated negative electrode collector, and the uncoated negative electrode collector serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be made of carbon, silicon, lithium metal, or a lithium alloy. To ensure that high current can pass without melting, the positive electrode tabs are multiple and stacked together, and the negative electrode tabs are multiple and stacked together. The separator can be made of polypropylene (PP) or polyethylene (PE). In addition, the electrode assembly in the embodiments of the present application includes but is not limited to a wound structure or a laminated structure.

[0096] Insulation areas are typically provided within battery cells, especially where electrical connections occur. This is particularly important to minimize the possibility of internal short circuits or live battery casings. For example, while a connecting member electrically connects the tabs of an electrode assembly to the electrode terminals, the contact area between the connecting member and the battery cell casing requires insulating tape to insulate the connection and reduce the possibility of live battery casings.

[0097] 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, thereby affecting the reliability of the battery cell.

[0098] In view of this, an embodiment of the present application provides a battery cell, in which a first insulating portion is provided on at least a portion of the surface of the connecting member of the battery cell facing the outer shell. Even if the connecting member is pre-connected to the outer shell of the battery cell, when the battery cell is assembled, the first insulating portion can achieve insulation between the connecting member and the outer shell, reducing the possibility of the outer shell being charged, thereby improving the reliability of the battery cell.

[0099] The technical solutions described in the embodiments of the present application are applicable to various battery-powered electrical devices. Electrical devices may be vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may be fuel vehicles, gas vehicles, or new energy vehicles. 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 devices.

[0100] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0101] As shown in Figure 1, it is a structural schematic diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 90, a controller 80 and a battery 10 can be provided 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 can be provided at the bottom, front or rear of the vehicle 1. The battery 10 can be used to power the vehicle 1. For example, the battery 10 can 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 of the vehicle 1 during startup, navigation and operation. In another embodiment of the present application, the battery 10 can not only serve 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.

[0102] To meet different power requirements, a battery can include multiple battery cells, which can be connected in series, parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections. A battery can also be referred to as a battery pack. Alternatively, multiple battery cells can be connected in series, parallel, or in a hybrid configuration to form a battery module, which can then be connected in series, parallel, or in a hybrid configuration to form a battery. In other words, multiple battery cells can be directly connected to form a battery, or they can be first connected to form battery modules, which can then be connected to form a battery.

[0103] For example, FIG2 shows a schematic structural diagram of a battery 10 according to an embodiment of the present application. 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 housing 11 having a hollow interior and housing the plurality of battery cells 20. FIG2 shows a possible implementation of the housing 11 according to an embodiment of the present application. As shown in FIG2 , the housing 11 may include two parts, referred to herein as a first part 111 and a second part 112, which are snap-fitted together. The shapes of the first part 111 and the second part 112 may be determined based on the shape of the battery module 200 assembly. At least one of the first part 111 and the second part 112 may have an opening. For example, as shown in FIG2 , the first part 111 and the second part 112 may each be a hollow cuboid with only one open face. The opening of the first part 111 and the opening of the second part 112 are arranged opposite each other, and the first part 111 and the second part 112 snap-fit ​​together to form the housing 11 having a closed chamber.

[0104] For another example, unlike that shown in Figure 2, only one of the first portion 111 and the second portion 112 may be a hollow rectangular parallelepiped with an opening, while the other may be a plate-shaped structure to cover the opening. For example, assuming that the second portion 112 is a hollow rectangular parallelepiped with only one open face, and the first portion 111 is a plate-shaped structure, the first portion 111 covers the opening of the second portion 112 to form a case 11 having a closed chamber, which can be used to accommodate multiple battery cells 20. The multiple battery cells 20 are connected in parallel, series, or in a mixed combination and then placed in the case 11 formed by the first portion 111 and the second portion 112 being fastened together.

[0105] Optionally, the battery 10 may also include other structures, which will not be described in detail here. For example, the battery 10 may also include a busbar component, which is used to achieve electrical connection between multiple battery cells 20, such as parallel connection, series connection, or mixed connection. Specifically, the busbar component can achieve electrical connection between the battery cells 20 by connecting the electrode terminals of the battery cells 20. Furthermore, the busbar component can be fixed to the electrode terminals of the battery cells 20 by welding. The electrical energy of the multiple battery cells 20 can be further led out through the conductive structure through the box body 11.

[0106] Depending on 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 in a mixed manner to achieve a larger capacity or power. Since the number of battery cells 20 included in each battery 10 may be large, for ease of 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 in a mixed manner.

[0107] Figure 3 shows a battery cell 20 provided in an embodiment of the present application. Figure 4 is a cross-sectional view of a portion of the battery cell 20 shown in Figure 3 along the AA direction. Figure 5 is an enlarged schematic diagram of the structure of the T portion in Figure 4. As shown in Figures 3 to 5, the battery cell 20 includes a housing 21, an electrode assembly 22, electrode terminals 23, and a connecting member 24. In this embodiment of the present application, the length of the battery cell can range from 300 mm to 800 mm, and the height can range from 50 mm to 250 mm.

[0108] The electrode assembly 22 is accommodated in the housing 21 , and the electrode terminal 23 is provided in the housing 21 . The connecting member 24 is used to connect the electrode terminal 23 and the electrode assembly 22 . A first insulating portion 31 is provided on at least a portion of the surface of the connecting member 24 facing the housing 21 .

[0109] 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 shaped according to the shape of the one or more electrode assemblies 22. For example, the outer shell 21 may be a rectangular parallelepiped, a cube, or a cylinder. The outer shell 21 may include a housing 210 and end caps 213. The housing 210 may be a hollow structure with an opening at at least one end. The shape of the end caps 213 may be adapted to the shape of the housing 210. The end caps 213 are used to cover the openings of the housing 210, so that the outer shell 211 isolates the internal environment of the battery cell 20 from the external environment. If the housing 210 is a hollow structure with an opening at one end, a single end cap 213 may be provided. Conversely, if the housing 210 is a hollow structure with openings at opposite ends, two end caps 213 may be provided, with the two end caps 213 respectively covering the openings at the ends of the housing 210. The shapes of the housing 210 and the end cap 213 complement each other. For example, as shown in FIG3 , the housing 210 may be a rectangular parallelepiped structure, and the end cap 213 may be a rectangular plate-shaped structure that matches the housing 210. For ease of explanation, this application uses the outer shell 21 as an example of a rectangular parallelepiped. The end cap 213 is connected to the housing 210 to form a closed cavity that accommodates the electrode assembly 22. The housing 210 is filled with an electrolyte, such as an electrolyte solution.

[0110] The electrode assembly 22 is the component within the battery cell 20 where the electrochemical reaction occurs. The electrode assembly 22 can be cylindrical, rectangular, or similar. If the electrode assembly 22 is cylindrical, the housing 210 can also be cylindrical. If the electrode assembly 22 is rectangular, the housing 210 can also be rectangular. For any electrode assembly 22, the electrode assembly 22 can include at least two tabs, each of which can include at least one positive tab and at least one negative tab. The positive tab can be formed by stacking portions of the positive electrode sheets that are not coated with the positive active material layer, while the negative tab can be formed by stacking portions of the negative electrode sheets that are not coated with the negative active material layer.

[0111] The housing 21 may also be provided with electrode terminals 23, which are used to electrically connect to the electrode assembly 22 to output electrical energy from the battery cell 20. The battery cell 20 may include at least two electrode terminals 23. 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, FIG3 only shows that one electrode terminal 23 is provided on one wall of the housing 21. In some embodiments, the other electrode terminal 23 may be provided on a wall opposite to the wall; in some embodiments, it may also be provided on a wall intersecting with the wall; in some embodiments, it may also be provided on the wall.

[0112] The connecting member 24, also known as a current collecting member, is disposed between the housing 21 and the electrode assembly 22 and is used to electrically connect the electrode assembly 22 to the electrode terminal 23. The positive electrode tabs of one or more electrode assemblies 22 are connected to the positive electrode terminal via one connecting member 24, and the negative electrode tabs of one or more electrode assemblies 22 are connected to the negative electrode terminal via another connecting member 24. The connecting member 24 and the tabs can be connected by laser welding or ultrasonic welding.

[0113] The first insulating portion 31 is disposed between the connecting member 24 and the housing 21 , as shown in FIG. 4 and FIG. 5 .

[0114] In some embodiments, a portion of the surface of the connecting member 24 facing the outer shell 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 the area where the connecting member 24 is connected to the electrode terminal 23 or the electrode assembly 22, and the non-connection area includes the area other than the connection area. On the surface of the connecting member 24 facing the outer shell 21, the connection area of ​​the connecting member 24 is connected to the electrode terminal 23, and at least a portion of the non-connection area is provided with the first insulating portion 31. For example, on the surface of the connecting member 24 facing the outer shell 21, the first insulating portion 31 can be provided in the portion of the non-connection area that is closer to the outer shell 21; for another example, on the surface of the connecting member 24 facing the outer shell 21, the non-connection area can be provided with the first insulating portion 31.

[0115] 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 can be electrically connected to the connection member 24 by connecting with the side wall of the through hole.

[0116] In the embodiment of the present application, the first insulating portion 31 can provide insulation between the connecting member 24 and the outer shell 21. This can reduce the possibility of the outer shell 21 becoming electrically 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 outer shell 21 is small, thereby improving the reliability of the battery cell 20. Furthermore, when the connecting member 24 and the outer shell 21 are pre-assembled, it is difficult to install an insulating component after the connecting member 24 and the outer shell 21 are pre-assembled. Therefore, the first insulating portion 31 can also reduce the difficulty of installing an insulating component between the connecting member 24 and the outer shell 21, thereby improving the processing efficiency of the battery cell 20.

[0117] According to some embodiments of the present application, the connecting member 24 includes a first connecting portion 241 , which is connected to the electrode assembly 22 , and the first insulating portion 31 includes a first insulating layer 311 , which is arranged on the surface of the first connecting portion 241 facing away from the electrode assembly 22 .

[0118] As shown in Figures 4 and 5, 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 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.

[0119] 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 and shortest sides of the battery cell 20. In other words, 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.

[0120] In the structure shown in FIG. 5 , 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 .

[0121] In some embodiments, the wall opposite to the first connection portion 241 may be the side wall of the battery cell 20. In this case, during assembly, it is difficult for there to be sufficient 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.

[0122] The first connecting portion 241 is relatively close to the outer shell 21 of the battery cell 20. Without the first insulating layer 311, the first connecting portion 241 and the outer shell 21 are likely to come into contact, causing the outer shell 21 to become electrically charged. Therefore, the first insulating layer 311 provides insulation between the connecting member 24 and the outer shell 21, reducing the possibility of the outer shell 21 becoming electrically charged, thereby improving the reliability of the battery cell 20.

[0123] 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 .

[0124] Figure 6 is a schematic diagram of the structure of a connecting member 24 provided in an embodiment of the present application, Figure 7 is a cross-sectional view of the connecting member 24 in Figure 6 along the BB direction, Figure 8 is a schematic diagram of the structure of Figure 6 from another perspective, and Figure 9 is a schematic diagram of the structure of another connecting member 24. As shown in Figures 6 to 9, a second insulating portion 32 is provided on at least a portion of the surface of the first connecting portion 241 that faces the electrode assembly 22.

[0125] In some embodiments, the surface of the first connection portion 241 facing the electrode assembly 22 may include a portion connected to the tab of the electrode assembly 22, i.e., a connection area of ​​the first connection portion 241, and a portion not connected to the tab of the electrode assembly 22, i.e., a non-connection area of ​​the first connection portion 241. 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, while also enabling the insulation performance of the first connection portion 241 to be achieved over the largest possible range.

[0126] 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 .

[0127] 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.

[0128] The edge of the surface of the first connecting portion 241 facing the electrode assembly 22 may refer to the edge of the first connecting portion 241 aligned 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, as shown in FIG8 , the second insulating portion 32 may be provided only in a region of at least one edge of the first connecting portion 241 aligned in the length direction X of the battery cell 20. For another example, as shown in FIG9 , the second insulating portion 32 may be provided in regions of all edges of the first connecting portion 241.

[0129] 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.

[0130] 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.

[0131] The first connection portion 241 may be a plate having a certain thickness. The first surface may refer to the surface between the surface of the first connection portion 241 facing the electrode assembly 22 and the surface of the first connection portion 241 facing away from the electrode assembly 22 that reflects 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. In some embodiments, the first surface may also be perpendicular to the length direction X of the battery cell 20.

[0132] A second insulating layer 312 is provided on at least a portion of the first surface. Figures 8 and 9 illustrate a situation where the entire first surface is covered by the second insulating layer 312. Figures 8 and 9 only illustrate the second insulating layer 312, not the first surface. It is 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 may be provided on only a portion of the first surface. For example, the second insulating layer 312 may be provided on a portion of the first surface that is likely to come into contact with the housing 210 or the end cap 213.

[0133] Providing the second insulating layer 312 on the first surface allows the surface of the first connection portion 241 facing the housing 21 of the battery cell 20 to be covered with the insulating structure as much as possible, thereby improving the insulation performance of the first connection portion 241 and improving the reliability of the battery cell 20.

[0134] 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 .

[0135] In some embodiments, the second insulating layer 312 can be connected to the first insulating layer 311. As shown in Figures 6 and 7, the corner between the surface of the first connecting 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.

[0136] In some embodiments, the second insulating layer 312 can be connected to the second insulating portion 32 , as shown in Figures 8 and 9 , and the corners of the surface of the first connecting portion 241 facing the electrode assembly 22 and the first surface can be insulated by the connection between the second insulating layer 312 and the second insulating portion 32 .

[0137] In some embodiments, the second insulating layer 312 can be simultaneously connected to the first insulating layer 311 and to the second insulating portion 32, so that the first insulating layer 311, the second insulating layer 312 and the second insulating portion 32 can be connected into 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 corners 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, thereby improving the insulation performance of the corresponding parts on the first connection portion 241, thereby improving the reliability of the battery cell 20.

[0138] This not only improves the insulation performance at the corners of the first connection portion 241, but also increases the adhesion of the first insulating layer 311, the second insulating layer 312, and the second insulating portion 32 to the surface of the first connection portion 241, thereby improving the insulation performance of the corresponding portions of the first connection portion 241 and thus enhancing the reliability of the battery cell 20. When the second insulating layer 312 is connected to both the first insulating layer 311 and the second insulating portion 32, the creepage distance between the first connection portion 241 and the housing 210 is increased, reducing the possibility of a short circuit between the first connection portion 241 and the housing 210.

[0139] 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 provided between a sidewall 2141 of the protrusion 214 and the first connecting portion 241 .

[0140] As shown in Figures 3 and 4, the protrusion 214 protrudes from the surface of the outer shell 21 facing the interior of the battery cell 20 into the interior of the battery cell 20, and the side wall 2141 of the protrusion 214 forms a certain angle with the top wall of the protrusion 214. Specifically, the protrusion 214 can protrude from the surface of the shell 210 facing the tab of the electrode assembly 22. The protrusion 214 forms a recess on the surface of the shell 210 facing away from the interior of the battery cell 20. The accommodation space formed by the bottom wall and side walls of the recess can generally be used to accommodate internal battery structures, such as thermal management components. Inside the battery cell 20, the side wall 2141 of the protrusion 214 is relatively close to the first connecting portion 241. When the battery cell 20 is shaken by external force, the first connecting portion 241 can easily contact the protrusion 214, causing the shell 210 of the battery cell 20 to become charged.

[0141] The second insulating layer 312 is disposed between the sidewall 2141 of the protrusion 214 and the first connecting portion 241. Specifically, the second insulating layer 312 is disposed at a location where the first connecting portion 241 is easily in contact with the protrusion 214. As shown in FIG4 , the second insulating layer 312 is disposed on a portion of the first surface of the first connecting portion 241 that faces the sidewall of the protrusion 214.

[0142] The second insulating layer 312 can reduce the possibility of charging due to the contact between the first connection portion 241 and the sidewall 2141 of the protrusion 214 , thereby improving the insulation performance of the battery cell 20 and thus improving the reliability of the battery cell 20 .

[0143] According to some embodiments of the present application, the connection member 24 includes a second connection portion 242 , which is bent relative to the first connection portion 241 and connected to the electrode terminal 23 .

[0144] As shown in Figures 3 to 9, 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 can be connected to the electrode terminal 23. In some embodiments, the second connection portion 242 can have a through-hole disposed opposite the electrode terminal 23, with at least a portion of the electrode terminal 23 accommodated in the through-hole. The electrode terminal 23 can then be electrically connected to the electrode terminal 23 via the sidewalls of the through-hole and / or the surface of the second connection portion 242 surrounding the through-hole.

[0145] 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.

[0146] The second connection portion 242 can make the position of the electrode terminal 23 more flexible, thereby making the internal structure arrangement of the battery cell 20 more flexible.

[0147] According to some embodiments of the present application, the first insulating portion 31 includes a third insulating layer 313 , and the third insulating layer 313 is provided on at least a portion of the surface of the second connecting portion 242 facing away from the electrode assembly 22 .

[0148] 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.

[0149] In some embodiments, a third insulating layer 313 is provided on at least a portion of the surface of the second connecting portion 242 facing away from the electrode assembly 22. Specifically, the third insulating layer 313 can be provided on at least a portion of the non-connection region of the surface of the second connecting portion 242 facing away from the electrode assembly 22. For example, as shown in FIG5 , the third insulating layer 313 is provided on a portion of the surface of the second connecting portion 242 facing away from the electrode assembly 22, and is disposed opposite a wall of the housing 210 of the battery cell 20, such as the first wall 211.

[0150] The third insulating layer 313 can insulate between the second connecting portion 242 and the housing 210 of the battery cell 20 , thereby reducing the possibility that the second connecting portion 242 conducts electrical energy to the housing 210 of the battery cell 20 and improving the insulation performance of the battery cell 20 .

[0151] According to some embodiments of the present application, the outer shell 21 includes an end cap 213 and a housing 210, wherein the end cap 213 covers the opening of the housing 210. The battery cell 20 also includes an insulating member 25, at least a portion of the insulating member 25 is disposed between the housing 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.

[0152] The outer shell 21 of the battery cell 20 may include a housing 210 and end caps 213. The housing 210 may be a hollow structure with an opening at least at one end, and the shape of the end caps 213 may be compatible with the shape of the housing 210. The end caps 213 are used to cover the opening of the housing 210, so that the housing 21 isolates the internal environment of the battery cell 20 from the external environment. If the housing 210 is a hollow structure with an opening at one end, a single end cap 213 may be provided. Conversely, if the housing 210 is a hollow structure with openings at opposite ends, two end caps 213 may be provided, one for each end opening of the housing 210. The shapes of the housing 210 and the end caps 213 complement each other. For example, as shown in FIG3 , the housing 210 may be a rectangular parallelepiped structure, and the end caps 213 may be rectangular plate-shaped structures that match the housing 210. For ease of illustration, this application uses 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 . The housing 210 is filled with an electrolyte, such as an electrolyte solution.

[0153] The insulating member 25 is a structure within the battery cell 20 that electrically isolates the outer shell 21 of the battery cell 20 from other structures within 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. The insulating member 25 can insulate the outer shell 21 from 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 insulate the electrode terminal 23 from the outer shell 21.

[0154] In the embodiment of the present application, as shown in FIG5 , 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 projections of the insulating member 25 and the electrode terminal 23 perpendicular to the length direction X of the battery cell 20 cover the second connection portion 242, the entire third insulating layer 313 may be disposed between the second connection portion 242 and the insulating member 25.

[0155] Accordingly, a certain amount of 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 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 the third insulating layer 313 to accommodate the third insulating layer 313; for another example, grooves may be provided at positions of the insulating member 25 opposite the third insulating layer 313 and at positions of the second connecting portion 242 opposite the third insulating layer 313, respectively, with these grooves together forming an accommodation space for the third insulating layer 313.

[0156] The third insulating layer 313 can further play an insulating role between the connecting member 24 and the insulating member 25 , thereby increasing the insulation effect between the second connecting portion 242 and the housing 21 , thereby improving the reliability of the battery cell 20 .

[0157] 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 .

[0158] As shown in Figures 5 to 10, 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.

[0159] In some embodiments, the thickness of the insulating member 25 is generally greater than the thickness of the second connecting 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 connecting portion 242. At the same time, it can also make the thickness of the second connecting portion 242 more uniform, thereby improving the conductive effect of the second connecting portion 242.

[0160] 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 shell 21. The creepage distance refers to the shortest path between two conductive components or between a conductive component and the equipment protection interface measured along the insulating surface. In this embodiment of the present application, the creepage distance between the second connecting portion 242 and the shell 21 refers to the shortest path between the second connecting portion 242 and the shell 21 that can be conducted through the insulating member 25.

[0161] Specifically, as shown in FIG10 , FIG10 (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. FIG10 (b) shows a case where the 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 points PQ-M'-N. The distance of the broken line segment of the points PQ-M'-N is greater than the distance between the points MN. When the insulating member 25 is polarized and exhibits a charged phenomenon, the charged area on the insulating member 25 can be kept away from the inner wall of the housing 21, thereby reducing the possibility of the housing 21 being charged.

[0162] 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.

[0163] The third insulating layer 313 provides insulation between the connecting member 24 and the outer shell 21 while increasing the creepage distance between the outer shell 21 and the connecting member 24. This reduces the possibility of electrical polarization of the insulating member 25, which could lead to electrical conduction between the connecting member 24 and the outer shell 21, thereby improving the reliability of the battery cell 20. Furthermore, the first groove 251 reduces the space occupied by the third insulating layer 313, thereby increasing energy density.

[0164] 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.

[0165] The second connection portion 242 may be a plate having a certain thickness. The second surface 244 may refer to the 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 reflects 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. 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 the end surface of the second connection portion 242 in the width direction Y of the battery cell 20.

[0166] At least a portion of the second surface 244 is provided with a fourth insulating layer 314. For example, the fourth insulating layer 314 may be provided on a portion of the second surface 244 that is likely to come into contact with the housing 210 or the end cap 213. Figures 8 and 9 illustrate a case where only a portion of the second surface 244 is covered with the fourth insulating layer 314. In some embodiments, the entire second surface 244 may be covered with the fourth insulating layer 314.

[0167] The fourth insulating layer 314 can cover as much of the surface of the second connection portion 242 as possible with the insulating structure, thereby improving the insulation performance of the second connection portion 242 and the reliability of the battery cell 20 .

[0168] According to some embodiments of the present application, a third insulating portion 33 is provided on at least a portion of the surface of the second connection portion 242 facing the electrode assembly 22 .

[0169] 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 .

[0170] 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.

[0171] In some embodiments, the end surface of the electrode assembly 22 facing the first connection part 241 may contact the second connection part 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 part 242 may contact the second connection part 242 and generate an electrical connection. Therefore, the third insulating part 33 can achieve insulation between the electrode assembly 22 and the second connection part 242.

[0172] 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.

[0173] 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 .

[0174] In an 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.

[0175] In some embodiments, the fourth insulating layer 314 can be connected to the third insulating layer 313. As shown in Figure 6, the corner between the surface of the second connecting portion 242 facing away from the electrode assembly 22 and the second surface 244 can be insulated by the connection between the second insulating layer 312 and the first insulating layer 311.

[0176] In some embodiments, the fourth insulating layer 314 can be connected to the third insulating portion 33. As shown in Figures 8 and 9, the corner between the surface of the second connecting 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.

[0177] In some embodiments, the fourth insulating layer 314 can be simultaneously connected to the third insulating layer 313 and the third insulating portion 33, so that the fourth insulating layer 314, the third insulating layer 313 and the third insulating portion 33 can be connected into a whole, forming a bending structure from the surface of the second connection portion 242 facing away from the electrode assembly 22 to the second surface 244, and then to the surface of the second connection portion 242 facing the electrode assembly 22. Furthermore, a structure that circles the second connection portion 242 can also be formed, which can not only improve the insulation performance at the corners between different surfaces of the second connection portion 242, but also increase the adhesion of the third insulating layer 313, the fourth insulating layer 314 and the third insulating portion 33 on the surface of the second connection portion 242, thereby improving the insulation performance of the corresponding parts on the second connection portion 242, thereby improving the reliability of the battery cell 20.

[0178] This not only improves the insulation performance at the corners between different surfaces of the second connecting portion 242, but also increases the adhesion of the third insulating layer 313, the fourth insulating layer 314, and the third insulating portion 33 to the surface of the second connecting portion 242, thereby improving the insulation performance of the corresponding portions of the second connecting portion 242 and thus enhancing 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 portion 33, the creepage distance between the second connecting portion 242 and the housing 210 is increased, reducing the possibility of electrical continuity between the second connecting portion 242 and the housing 210.

[0179] 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.

[0180] As shown in Figures 5 to 10, the first connecting portion 241 and the second connecting portion 242 can extend in different directions. If the connecting member 24 is bent as a whole, the first connecting portion 241 and the second connecting portion 242 can be connected via a third connecting portion 243. In some embodiments, the third connecting portion 243 can be a plate in the shape of an arc. Specifically, the third connecting portion 243 can be in the shape of an arc in the cross-section AA shown in Figures 3 and 4. In some embodiments, the third connecting portion 243 can also be a plate of other shapes, such as a flat plate, and can form a certain angle with the first connecting portion 241 and the second connecting portion 242, respectively, thereby connecting the first connecting portion 241 and the second connecting portion 242 extending in different directions.

[0181] 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.

[0182] 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 provided on at least a portion of the surface of the third connecting portion 243 facing away from the electrode assembly 22 .

[0183] As shown in Figures 4 to 9, 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.

[0184] In some embodiments, the fifth insulating layer 315 can 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 can be connected in an integrally formed manner. This allows the insulating layers of different portions to be tightly covered on the surface of the connecting member 24, reducing the possibility of gaps between the insulating layers of different portions and improving the insulation performance of the connecting member 24.

[0185] The fifth insulating layer 315 can provide insulation for the connecting member 24 on the side of the third connecting portion 243 facing the housing 21 , thereby achieving insulation between the third connecting portion 243 and the shell 210 and reducing the possibility of the housing 21 being charged.

[0186] According to some embodiments of the present application, the third connecting portion 243 has a third surface, which 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; 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.

[0187] The third connection portion 243 has a certain thickness. The third surface may refer to a surface between a surface of the third connection portion 243 facing the electrode assembly 22 and a surface of the third connection portion 243 facing away from the electrode assembly 22 that reflects 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.

[0188] In a battery cell 20, the third surface is typically relatively close to the end cap 213 or the bottom wall of the housing 210 of the battery cell 20. Therefore, a sixth insulating layer 316 may be provided on at least a portion of the third surface. Figures 6 to 9 illustrate a case where the entire third surface is covered by the sixth insulating layer 316. Figures 6 to 9 only illustrate the sixth insulating layer 316 and not the third surface. It is 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 likely to come into contact with the housing 210 or the end cap 213.

[0189] 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 .

[0190] According to some embodiments of the present application, 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 .

[0191] 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 part 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.

[0192] 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 .

[0193] 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 .

[0194] In an 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.

[0195] In some embodiments, the sixth insulating layer 316 can be connected to the fifth insulating layer 315. As shown in Figure 6, the corner between the surface of the third connecting 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.

[0196] In some embodiments, the sixth insulating layer 316 can be connected to the fourth insulating portion 34 , as shown in Figures 8 and 9 , and the corners of the surface of the third connecting 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 .

[0197] In some embodiments, the sixth insulating layer 316 can be simultaneously connected to the fifth insulating layer 315 and the fourth insulating part 34, so that the sixth insulating layer 316, the fifth insulating layer 315 and the fourth insulating part 34 can be connected into a whole, forming a bending structure from the surface of the third connection part 243 facing away from the electrode assembly 22 to the third surface, and then to the surface of the third connection part 243 facing the electrode assembly 22. Furthermore, a structure that circles the third connection part 243 can also be formed, which can not only improve the insulation performance at the corners between different surfaces of the third connection 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 connection part 243, thereby improving the insulation performance of the corresponding parts on the third connection part 243, thereby improving the reliability of the battery cell 20.

[0198] 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, thereby improving the insulation performance of the corresponding parts on the third connection part 243, thereby improving the reliability of the battery cell 20.

[0199] 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 formed as one piece.

[0200] 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 insulating components on the connecting member 24 after the connecting member 24 is connected to the electrode assembly 22 or the electrode terminal 23.

[0201] 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 to the connecting member 24, reduce the connection gaps between insulating components in different areas of the connecting member 24, and improve the connection strength between insulating components in different areas of 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 other methods, thereby improving assembly efficiency.

[0202] 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 .

[0203] As shown in Figures 3 to 5, the housing 210 of the battery cell 20 can be a hollow structure with an opening. The housing 210 includes multiple walls that enclose a storage space. The housing 210 can have an opening at one end, and the battery cell 20 can include an end cap 213 to cover the opening. In some embodiments, the housing 210 can have openings at both ends, and the battery cell 20 can include two end caps 213, one for covering the two end openings of the housing 210. The shape of the housing 210 can be determined based on the shape of the one or more electrode assemblies 22 after assembly. For example, the housing 210 can be a hollow rectangular parallelepiped, a cube, or a cylinder, with at least one surface of the housing 210 having an opening to allow the one or more electrode assemblies 22 to be placed within the housing 210. For example, when the housing 210 is a hollow rectangular parallelepiped or a cube, one of the planes of the housing 210 is an open surface, i.e., the plane has no walls, allowing the inside and outside of the housing 210 to communicate. When the housing 210 is a hollow cylinder, the end surface of the housing 210 is an open surface, that is, the end surface has no wall, so that the inside and outside of the housing 210 are connected. The end cap 213 can be a wall covering the opening and connected to the housing 210. The end cap 213 is sealed to the housing 210 to form a closed cavity for accommodating the electrode assembly 22.

[0204] 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, FIG3 shows only one electrode terminal 23 disposed on one wall of the housing 21. In some embodiments, the other electrode terminal 23 may be disposed on a wall opposite to the wall; in some embodiments, it may be disposed on a wall intersecting with the wall; and in some embodiments, it may be disposed on the wall.

[0205] The arrangement of the electrode terminal 23 in the housing 210 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 .

[0206] According to some embodiments of the present application, the housing 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 tab is disposed on the side of the electrode assembly 22 facing the second wall 212 .

[0207] As shown in Figures 3 to 5, the housing 210 may include side walls and a bottom wall. The bottom wall is opposite the opening of the housing 210, that is, opposite the end cap 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 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.

[0208] The first wall 211 and the second wall 212 are connected. The electrode terminal 23 is provided on the first wall 211 and is electrically connected to the connecting member 24. 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 tab facing the second wall 212.

[0209] This structure allows for greater flexibility in the positioning of the electrode terminals 23 and the tabs, allowing for the placement of the electrode terminals 23 and the tabs to be tailored to meet varying needs. Furthermore, the curved shape of the connecting member 24 facilitates electrical connection between the electrode terminals 23 and the tabs at different locations, further flexibly arranging the internal structure of the battery cell 20.

[0210] 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, and the projection area of ​​the end cover 213 in the direction perpendicular to the thickness of the end cover 213 is larger than the projection area of ​​the first wall 211 in the direction perpendicular to the thickness of the first wall 211, and the projection area of ​​the end cover 213 in the direction perpendicular to the thickness of the end cover 213 is larger than the projection area of ​​the second wall 212 in the direction perpendicular to the thickness of the second wall 212.

[0211] The shell 210 of the battery cell 20 may include a first wall 211 and a second wall 212. In some embodiments, the side walls of the shell 210 include 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.

[0212] The end cover 213 can be approximately a flat plate-shaped structure, and the projected area of ​​the end cover 213 in the 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 projected area of ​​the first wall 211 in the direction perpendicular to the thickness of the end cover 213 is the area of ​​the first wall 211, and the projected area of ​​the second wall 212 in the direction perpendicular to the thickness of the end cover 213 is the area of ​​the second wall 212.

[0213] 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 multiple first walls 211, the area of ​​the end cap 213 can 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 multiple second walls 212, the area of ​​the end cap 213 can be greater than the area of ​​each second wall 212. In some embodiments, the area of ​​the end cap 213 can be greater than both the area of ​​the first wall 211 and the area of ​​the second wall 212.

[0214] When the area of ​​the end cover 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. Then, the portion of the connecting member 24 that may be in contact with the end cover 213 is smaller, and insulation between the connecting member 24 and the end cover 213 can be achieved through fewer insulating structures.

[0215] 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.

[0216] The connecting member 24 and the tab of the electrode assembly 22 are typically connected by laser welding. Therefore, the insulating component on the surface of the connecting member 24 must maintain its original state even under the high temperatures generated by welding to provide reliable insulation performance. In some embodiments, a melting point of the first insulating portion 31 greater than 100°C can effectively reduce the impact of the welding process on the first insulating portion 31, thereby achieving good insulation between the first insulating portion 31 and the first connecting portion 241, and improving the reliability of the battery cell 20. In some embodiments, the material of the first insulating portion 31 can be FPA, polypropylene (PP), etc.

[0217] 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.

[0218] 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 , where K satisfies 1 mm ≤ K ≤ 5 mm.

[0219] As shown in Figures 5 to 10, in the embodiment of the present application, the second connecting portion 242 can extend in the width direction Y of the battery cell 20. The portion of the fourth insulating layer 314 located between the second connecting portion 242 and the insulating member 25 in the width direction Y of the battery cell 20 has a dimension 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 meeting the above numerical range can effectively increase the creepage distance between the second connecting portion 242 and the outer shell 21, making the outer shell 21 less susceptible to electrical charge. This also reduces the possibility of the second insulating layer 312 interfering with the connection between the second connecting portion 242 and the electrode terminal 23.

[0220] According to some embodiments of the present application, a distance L1 from the edge of the connecting member 24 to the 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.

[0221] Figure 11 is a schematic cross-sectional view of the structure of the connecting member 24, the first insulating portion 31, and the second insulating portion 32 in Figure 8 along the CC direction, and Figure 12 is a schematic cross-sectional view of the structure of the connecting member 24, the first insulating portion 31, and the second insulating portion 32 in Figure 9 along the FF direction. As shown in Figures 11 and 12, the portion of the second insulating portion 32 provided 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, the dimension of the second connecting portion 242 in a direction perpendicular to the edge of the first connecting portion 241 is L1. L1 satisfies 1mm≤L1≤5mm. For example, L1 can be 1mm, 2mm, 2.2mm, 3mm, 3.6mm, 4mm, 4.2mm, 5mm, etc. When L1 satisfies the above numerical range, the adhesion of the first insulating portion 31 and the second insulating portion 32 to the connecting member 24 can be effectively increased, so that the first insulating portion 31 and the second insulating portion 32 are not easily detached from the connecting member 24 , thereby providing better insulation performance for the battery cell 20 .

[0222] 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 , where S satisfies 0.1 mm ≤ S ≤ 1 mm.

[0223] The electrode assembly 22 is generally formed by winding or stacking a positive electrode sheet, a negative electrode sheet, and a separator. The tab extends from one surface of the electrode assembly 22 and protrudes from the surface.

[0224] The stacking direction of the positive electrode sheets and the negative electrode sheets 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. The stacking area and the bending area are sequentially connected to form a waist-shaped electrode assembly 22. The arrangement direction of the electrode sheets in the stacking area is the stacking direction of the positive electrode sheets and the negative electrode sheets. In some embodiments, the electrode assembly 22 is stacked by stacking, for example, a continuous electrode sheet can be stacked with multiple cut electrode sheets, or multiple cut positive electrode sheets can be stacked with multiple cut negative electrode sheets. The arrangement direction of the stacked electrode sheets is the stacking direction of the positive electrode sheets and the negative electrode sheets.

[0225] In the embodiment of the present application, the tab of the electrode assembly 22 is connected to the first connecting portion 241, and the surface of the electrode assembly 22 is opposite to the first connecting 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 connecting portion 241 is S shown in Figure 13, wherein Figure 13 is an enlarged structural schematic diagram of part G in Figure 5. S satisfies 0.1mm≤S≤1mm. For example, S can be 0.1mm, 0.2mm, 0.26mm, 0.3mm, 0.mm, 0.4mm, 0.5mm, 0.58mm, 0.6mm, 0.7mm, 0.8mm, 0.83mm, 0.9mm, 1mm, etc. S meeting the above numerical range can reduce the possibility of interference between the electrode assembly 22 and the second insulating portion 32, and at the same time, it can also insulate and protect the third connecting portion 243 as much as possible.

[0226] 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.

[0227] FIG14 is an enlarged structural diagram of portion E in FIG7 . As shown in FIG14 , in some embodiments, the first insulating portion 31 may be a film having a uniform thickness. The thickness of the first insulating portion 31 may be referred to as H1 in FIG12 . H1 satisfies 0.2 mm ≤ H1 ≤ 0.8 mm. For example, H1 may be 0.2 mm, 0.26 mm, 0.3 mm, 0.1 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 allows the first insulating portion 31 to provide good insulation between the first connecting portion 241 and the outer shell 21 while not occupying excessive internal space of the battery cell 20.

[0228] Similarly, the thickness of the second insulating portion 32 is H2, and H2 can satisfy 0.2 mm ≤ H2 ≤ 0.8 mm. For example, H2 can be 0.2 mm, 0.26 mm, 0.3 mm, 0.0 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 can also be within the above range.

[0229] An embodiment of the present application further provides a battery, comprising the battery cell 20 provided in any of the above embodiments.

[0230] An embodiment of the present application further provides an electrical device, comprising the battery provided in any of the above embodiments, wherein the battery is used to provide electrical energy to the electrical device.

[0231] An embodiment of the present application also provides an energy storage device, comprising the battery provided in any of the above embodiments.

[0232] The present embodiment further provides a method 400 for preparing a battery cell 20, which is used to prepare the battery cell 20 provided by any of the above embodiments. Specifically, as shown in FIG15 , the method 400 includes at least the following steps.

[0233] 410. A first insulating portion 31 is provided on the surface of the connecting member 24;

[0234] 420. Connect one end of the connecting member 24 to the electrode terminal 23 provided on the housing 21 and position the first insulating portion 31 between the housing 21 and the connecting member 24.

[0235] 430 . Connect the other end of the connecting member 24 to the electrode assembly 22 .

[0236] In the method for preparing the battery cell 20 , the first insulating portion 31 may be provided on the surface of the connecting member 24 . Specifically, when the connecting member 24 is assembled, the first insulating portion 31 may be provided on at least a portion of the surface of the connecting member 24 facing the housing 21 .

[0237] 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.

[0238] The other end of the connecting member 24 is connected to the electrode assembly 22. The surface of the connecting member 24 connected to the electrode assembly 22 is provided with a first insulating portion 31, and one end of the connecting member 24 is connected to the electrode terminal 23. In other words, 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 outer casing 21 of the battery cell 20 is already provided with the first insulating portion 31, eliminating the need to further provide an insulating structure on the surface of the connecting member 24 after the connection with the electrode terminal 23 and the electrode assembly 22 is completed.

[0239] By providing 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 providing 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.

[0240] 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.

[0241] The first connection portion 241 and the second connection portion 242 can extend in different directions, and the connecting member 24 is bent as a whole. The first connection portion 241 and the second connection portion 242 can be connected via the third connection portion 243. The third connection portion 243 can electrically connect the electrode assembly 22 and the battery cell 20, which are respectively located on two intersecting planes, thereby improving the flexibility of the internal structure arrangement of the battery cell 20.

[0242] 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.

[0243] A second insulating portion 32, a third insulating portion 33, and a fourth insulating portion 34 may also be provided on the surface of the connecting member 24. During the process of connecting the connecting member 24 to the electrode terminal 23 and 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.

[0244] In this way, when the connecting member 24 is in a fully assembled state, insulation can be achieved between the surface of the connecting member 24 facing the electrode assembly 22 and the electrode assembly 22 , thereby improving the insulation performance of the battery cell 20 .

[0245] According to some embodiments of the present application, the housing 21 includes an end cap 213 and the housing 210. The method 400 further includes: with one end of the connecting member 24 connected to the electrode terminal 23 provided on the housing 21, with the first insulating portion 31 positioned between the housing 21 and the connecting member 24, and with the other end of the connecting member 24 connected to the electrode assembly 22, closing the opening of the housing 210 with the end cap 213.

[0246] 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 can be covered with 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.

[0247] According to some embodiments of the present application, the housing 210 includes a side wall and a bottom wall, the bottom wall being opposite to the opening. Step 420 may specifically include: connecting one end of the connecting member 24 to the electrode terminal 23 provided on the outer shell 21 and positioning the first insulating portion 31 between the side wall and the connecting member 24.

[0248] 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, making it 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 provided on the outer shell 21, the first insulating part 31 is provided between the side wall of the shell 210 and the connecting member 24, so that the first insulating part 31 can provide a better insulation effect inside the battery cell 20, thereby improving the reliability of the battery cell 20.

[0249] An embodiment of the present application provides a battery cell 20, which includes an outer shell 21, an electrode assembly 22, an electrode terminal 23, and a connecting member 24. The outer shell 21 includes a shell 210 and an end cap 213. The shell 210 includes a first wall 211 and a second wall 212 that intersect each other. The electrode terminal 23 is disposed on the first wall 211. The 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 disposed between the electrode assembly 22 and the second wall 212. The second connecting portion 242 is connected to the electrode terminal 23 and is disposed between the first wall 211 and the electrode assembly 22. The third connecting portion 243 connects the first connecting portion 241 and the second connecting portion 242.

[0250] At least a portion of the surface of the connecting 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 .

[0251] 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.

[0252] 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 and the surface of the second connecting portion 242 facing away from the electrode assembly 22.

[0253] The surface of the third connecting part 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 part 34, wherein the third surface connects the surface of the third connecting part 243 facing the electrode assembly 22 and the surface of the third connecting part 243 facing away from the electrode assembly 22.

[0254] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection 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 housing includes a first wall and a second wall adjacent to each other, the electrode terminal is disposed on the first wall, A pole ear is arranged on one side of the pole 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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