Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device. A battery cell includes: a case; the electrode assembly is located in the shell and comprises an electrode main body and a tab, the electrode main body comprises a first end face and a second end face which are oppositely arranged in the first direction and a side face connected between the first end face and the second end face, and the tab is connected to the electrode main body and extends out of at least one of the first end face and the second end face; the heat conduction assembly comprises an insulating part and a heat conduction part, at least part of the insulating part forms a containing cavity, the heat conduction part is arranged in the containing cavity, the insulating part at least covers the side face, and the heat conduction part comprises a first heat conduction piece which is arranged on at least part of the side face and is in heat conduction connection with the side face. The thermal conductivity of the heat conduction piece is larger than that of the insulating piece and that of the shell.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery cell, a battery device, and an electrical device. Background Art

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

[0003] However, during actual operation of a battery cell, if its internal temperature is too high or too low, it will have an adverse effect on the service life and performance of the battery cell. Utility Model Content

[0004] In view of the above problems, the present application provides a battery cell, a battery device and an electrical device, which can enhance the thermal conductivity between the electrode assembly inside the battery cell and the external environment to balance the internal temperature of the battery cell and improve the performance and service life of the battery cell.

[0005] In the first aspect, the present application provides a battery cell, comprising: a shell; an electrode assembly, located in the shell, the electrode assembly including an electrode body and a tab, the electrode body including a first end face and a second end face arranged opposite to each other in a first direction, and a side surface connected between the first end face and the second end face, the tab is connected to the electrode body and extends out of at least one of the first end face and the second end face; a heat-conducting assembly, comprising an insulating member and a heat-conducting member, the insulating member forming a receiving cavity in at least a partial area, the heat-conducting member being arranged in the receiving cavity, the insulating member at least covering the side surface, the heat-conducting member including a first heat-conducting plate, the first heat-conducting plate being arranged on at least a portion of the side surface and being heat-conductingly connected to the side surface, the thermal conductivity of the heat-conducting member being greater than the thermal conductivity of the insulating member and the thermal conductivity of the shell.

[0006] In the embodiment of the present application, the battery cell includes a shell, an electrode assembly and a heat-conducting assembly. The electrode assembly is located inside the shell, and the shell provides accommodation and protection for the electrode assembly. The electrode assembly includes an electrode body and a pole ear. The electrode body includes a first end face and a second end face arranged opposite to each other in a first direction, and a side surface connected between the first end face and the second end face. The electrode body forms a loop with the pole ear extending from the first end face and / or the second end face and an external component. The heat-conducting assembly includes an insulating part and a heat-conducting part. The insulating part at least covers the side surface. The insulating part is insulated from the shell and at least part of the electrode assembly. The insulating part can replace at least part of the Mylar film to reduce the preparation cost of the battery cell, reduce the thickness of the battery cell, and improve the energy density of the battery cell. The insulating part is at least partially An accommodating cavity is formed in different areas, and a heat conductive member is arranged in the accommodating cavity. The heat conductive member and the electrode body can be insulated by the insulating member, and the heat conductive member and the electrolyte can be isolated by the insulating member to improve the incompatibility problem between the heat conductive member and the electrolyte. The thermal conductivity of the heat conductive member is greater than the thermal conductivity of the insulating member and the thermal conductivity of the shell. The heat conductive member includes a first heat conductive plate, which is arranged on at least part of the side and is heat-conductively connected to the side. The first heat conductive plate is used to reduce the thermal resistance of the electrode body at its side, improve the temperature uniformity of the electrode body at its side, and improve the rate of heat exchange between the electrode body at its side and the external environment, so as to balance the internal temperature of the battery cell and improve the problem that the performance and service life of the battery cell are adversely affected by the internal temperature of the battery cell being too high or too low.

[0007] In some embodiments, the tab extends from the first end surface, and the insulating member covers the second end surface and side surfaces of the electrode body.

[0008] In the technical solution of the embodiment of the present application, the insulating part covers the second end face and side surface of the electrode body to insulate the shell and the electrode assembly, and there is no need to set a Mylar film, which helps to reduce the cost of preparing the battery cell, and can reduce the thickness of the battery cell and improve the energy density of the battery cell.

[0009] In some embodiments, the side includes two first side surfaces and two second side surfaces, the two first side surfaces are arranged opposite to each other in the second direction, the two second side surfaces are arranged opposite to each other in the third direction, the first direction, the second direction and the third direction intersect with each other, the area of ​​the first side surface is greater than the area of ​​the second side surface, the insulating member includes a first insulating portion, the first insulating portion includes a main body portion and a bending portion connected to each other, the main body portion and the bending portion are connected, the main bodies of the two first insulating portions are respectively arranged on the two first side surfaces, the two bending portions are respectively arranged on the two second side surfaces, and the first thermal conductive sheet is arranged on at least one of the main body portion and the bending portion.

[0010] In the technical solution of the embodiment of the present application, the first insulating part includes a main body part and a bending part that are connected to each other, the main body part and the bending part are connected, the main bodies of the two first insulating parts are respectively arranged on the two first side surfaces, and the two bending parts are respectively arranged on the two second side surfaces to achieve insulation of the electrode assembly on its circumferential side surface and the shell, and the first thermal conductive sheet is arranged on at least one of the main body part and the bending part to improve the thermal conductivity rate at the first side surface and / or second side surface of the electrode assembly.

[0011] In some embodiments, a first through hole is provided through the first insulating portion, and the first through hole and the accommodating cavity are spaced apart.

[0012] In the technical solution of the embodiment of the present application, a first through hole is provided through the first insulating part so that the electrolyte can infiltrate the electrode assembly through the first through hole. The first through hole and the accommodating cavity are spaced apart to avoid contact between the electrolyte and the first thermal conductive plate.

[0013] In some embodiments, a first avoidance hole is provided through the first heat conducting plate, the first insulating portion covers the inner wall of the first avoidance hole, a first through hole is provided through the first insulating portion, and the first through hole is located in the first avoidance hole.

[0014] In the technical solution of the embodiment of the present application, a first avoidance hole is provided through the first thermal conductive sheet, and a first through hole is provided through the first insulating portion. The first through hole is located in the first avoidance hole so that the electrolyte can penetrate into the electrode assembly through the first through hole and the first avoidance hole. The first insulating portion covers the inner wall of the first avoidance hole to avoid contact between the electrolyte and the first thermal conductive sheet and to keep the first thermal conductive sheet and the electrode assembly insulated.

[0015] In some embodiments, the electrode tab extends from the first end face, and the insulating member also includes a second insulating portion, which is arranged between the second end face of the electrode body and the shell, and the second insulating portion is insulated from the shell and the second end face of the electrode assembly, and the main bodies of the two first insulating portions are respectively connected to the two sides of the second insulating portion.

[0016] In the technical solution of the embodiment of the present application, the insulating part also includes a second insulating part arranged between the second end face of the electrode body and the shell, and the main bodies of the two first insulating parts are respectively connected to the two sides of the second insulating part, thereby reducing the difficulty of aligning the second insulating part and the first insulating part, and reducing the difficulty of matching the insulating part and the electrode assembly.

[0017] In some embodiments, the heat conducting member includes a second heat conducting sheet, and the second heat conducting sheet is disposed on the second insulating portion.

[0018] In the technical solution of the embodiment of the present application, the heat conducting member includes a second heat conducting sheet arranged on the second insulating portion to improve the heat conduction rate at the second end surface.

[0019] In some embodiments, a second through hole is provided through the second insulating portion, and the second through hole and the accommodating cavity are spaced apart.

[0020] In the technical solution of the embodiment of the present application, a second through hole is provided through the second insulating part so that the electrolyte can infiltrate the electrode assembly through the second through hole. The second through hole and the accommodating cavity are spaced apart to avoid contact between the electrolyte and the second thermal conductive plate.

[0021] In some embodiments, a second avoidance hole is provided through the second heat conducting plate, the second insulating portion covers the inner wall of the second avoidance hole, a second through hole is provided through the second insulating portion, and the second through hole is located in the second avoidance hole.

[0022] In the technical solution of the embodiment of the present application, a second avoidance hole is provided through the second thermal conductive sheet, and a second through hole is provided through the second insulating portion. The second through hole is located in the second avoidance hole so that the electrolyte can penetrate into the electrode assembly through the second through hole and the second avoidance hole. The second insulating portion covers the inner wall of the second avoidance hole to prevent the electrolyte from contacting the second thermal conductive sheet and to keep the second thermal conductive sheet and the electrode assembly insulated.

[0023] In some embodiments, a plurality of electrode assemblies are provided, and the plurality of electrode assemblies are stacked along the second direction. The insulating member further includes a middle insulating portion, which is provided between the electrode bodies of adjacent electrode assemblies. The middle insulating portion and the second insulating portion are connected to each other. The first thermal conductive plate includes an intermediate thermal conductive plate, which is provided in the middle insulating portion.

[0024] In the technical solution of the embodiment of the present application, the middle insulating part is arranged between adjacent electrode bodies to insulate the adjacent electrode bodies, the middle insulating part and the second insulating part are connected to each other to improve the insulation reliability of the middle insulating part, and the intermediate heat conducting plate is arranged in the middle insulating part to improve the thermal conductivity between adjacent electrode bodies.

[0025] In some embodiments, the first thermally conductive sheet and the second thermally conductive sheet are connected to each other.

[0026] In the technical solution of the embodiment of the present application, the heat conducting member includes a second heat conducting plate arranged on the second insulating part, and the first heat conducting plate and the second heat conducting plate are connected to each other so that the heat between adjacent electrode assemblies can be transferred to the second heat conducting plate through the first heat conducting plate, and exchange heat with the external environment, thereby improving the thermal conductivity rate of the heat conducting assembly.

[0027] In some embodiments, a bending portion is connected to both sides of the main body in the third direction, and the two bending portions of the two first insulating portions and located on the same side of the electrode assembly extend toward each other in the second direction.

[0028] In the technical solution of the embodiment of the present application, the main body is connected to a bending portion on both sides of the third direction, and the two bending portions of the two first insulating portions and located on the same side of the electrode assembly extend toward each other in the second direction. The joint of the two bending portions is located on the second side surface, and the first side surface with a larger area can be provided with a larger area of ​​a thermal conductive layer to improve the thermal conductivity of the thermal conductive assembly.

[0029] In some embodiments, the two bending portions extend toward each other in the second direction, and the two bending portions at least partially overlap in the third direction.

[0030] In the technical solution of the embodiment of the present application, the two bent portions extend toward each other in the second direction, and the two bent portions at least partially overlap in the third direction to improve the insulation reliability of the first insulating portion between the electrode assembly and the shell.

[0031] In some embodiments, the shell includes an opening in a first direction, the battery cell also includes a top cover assembly, the top cover assembly covers the opening and is connected to the tab, and at least one main body extends from the first end surface in the first direction and is connected to the top cover assembly.

[0032] In the technical solution of the embodiment of the present application, at least one main body portion extends from the first end surface in a first direction and is connected to the top cover assembly. The top cover assembly plays a role in positioning and fixing the heat-conducting assembly, thereby improving the stability of the heat-conducting assembly in the shell.

[0033] In some embodiments, a dimension L3 of the main body extending from the first end surface in the first direction is ≥2 mm.

[0034] In the technical solution of the embodiment of the present application, when the above conditions are met, the connection reliability between the heat conducting component and the top cover component is improved.

[0035] In some embodiments, a minimum distance between an orthographic projection of the heat conducting member in the thickness direction of the heat conducting assembly and an edge of an orthographic projection of the insulating member in the thickness direction of the heat conducting assembly is greater than or equal to 2 mm.

[0036] In the technical solution of the embodiment of the present application, the minimum distance from the edge of the orthographic projection of the heat conducting part in the thickness direction of the heat conducting component to the orthographic projection of the insulating part in the thickness direction of the heat conducting component is greater than or equal to 2 mm, so that there is a sufficient plastic sealing area between the heat conducting part and the edge of the insulating part to improve the sealing reliability of the accommodating cavity.

[0037] In some embodiments, the thickness D3 of the thermal conductor satisfies 40 μm≤D3≤180 μm.

[0038] In the technical solution of the embodiment of the present application, when the above conditions are met, it can not only improve the problem that the battery cell volume is too large and the energy density is reduced due to the heat conductor being too thick, but also improve the problem that the heat conductor is easily damaged due to being too thin.

[0039] In some embodiments, the insulating member includes two sub-insulating layers, which are stacked and connected to each other to form a receiving cavity. The thickness D1 of the sub-insulating layer satisfies 5 μm≤D1≤100 μm.

[0040] In the technical solution of the embodiment of the present application, when the above conditions are met, it can not only improve the problem that the sub-insulating layer is too thick, resulting in a large volume of the battery cell and reduced energy density, but also improve the problem that the sub-insulating layer is too thin and easily damaged.

[0041] In some embodiments, the insulation comprises polyethylene or polypropylene or polyimide or polyester resin.

[0042] In the technical solution of the embodiment of the present application, the insulating member includes polyethylene or polypropylene or polyimide or polyester resin to improve the insulation reliability of the insulating member.

[0043] In some embodiments, the thermal conductor includes graphite or graphene or carbon nanotubes.

[0044] In the technical solution of the embodiment of the present application, the heat conducting member includes graphite, graphene or carbon nanotubes, and the thermal conductivity of the heat conducting component is improved by using the graphite, graphene or carbon nanotube thermal conductive materials.

[0045] In some embodiments, the thermal conductivity k of the heat conducting member satisfies k>500 W / (m·K).

[0046] In the technical solution of the embodiment of the present application, when the thermal conductivity k of the heat conducting member meets the above conditions, the heat conducting component has sufficient thermal conductivity to conduct the heat of the electrode body.

[0047] In a second aspect, an embodiment of the present application provides a battery device comprising a battery cell according to any one of the embodiments of the first aspect.

[0048] In a third aspect, an embodiment of the present application provides an electrical device, comprising the battery device of the embodiment of the second aspect described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0050] Figure 1 is a structural schematic diagram of a vehicle provided in one embodiment of the present application;

[0051] Figure 2 is a structural diagram of a battery device provided in one embodiment of the present application;

[0052] Figure 3 This is a schematic structural diagram of a battery module provided in one embodiment of the application;

[0053] Figure 4 is an exploded view of a battery cell provided in one embodiment of the present application;

[0054] Figure 5 This is a schematic structural diagram of an electrode assembly of a battery cell provided in one embodiment of the present application;

[0055] Figure 6 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0056] Figure 7 yes Figure 6 Cross-sectional view at AA in the middle;

[0057] Figure 8 is an exploded view of a battery cell provided in another embodiment of the present application;

[0058] Figure 9 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0059] Figure 10 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0060] Figure 11 This is an expanded view of a thermally conductive component of a battery cell provided in one embodiment of the present application;

[0061] Figure 12 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0062] Figure 13 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0063] Figure 14 This is a partial structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0064] Figure 15 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0065] Figure 16This is a partial structural diagram of a heat-conducting component of a battery cell provided in another embodiment of the present application;

[0066] Figure 17 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0067] Figure 18 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0068] Figure 19 This is a partial structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0069] Figure 20 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0070] Figure 21 This is a partial structural diagram of a heat-conducting component of a battery cell provided in another embodiment of the present application;

[0071] Figure 22 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application;

[0072] Figure 23 This is an expanded view of a thermally conductive component of a battery cell provided in one embodiment of the present application.

[0073] Reference numerals:

[0074] 1. Vehicle; 101. Motor; 102. Controller; 2. Battery device; 201. Battery module; 202. Case; 2021. First case; 2022. Second case;

[0075] 3. Battery cells;

[0076] 4. Shell; 41. Opening;

[0077] 5. Electrode assembly; 51. Tab; 52. Electrode body; 521. First end surface; 522. Second end surface; 523. Side surface; 5231. First side surface; 5232. Second side surface;

[0078] 6. Top cover assembly;

[0079] 8. Thermal conductive component; 815. First through hole; 821. Second through hole;

[0080] 84. Thermal conductor; 85. Insulating member; 851. Accommodating cavity; 852. First insulating portion; 8521. Main body; 8522. Bend portion; 853. Second insulating portion; 854. Middle insulating portion; 855. Sub-insulating layer; 841. First thermally conductive sheet; 842. Second thermally conductive sheet; 8414. First avoidance hole; 8421. Second avoidance hole; 856. Plastic sealing area; 8411. Middle thermally conductive sheet; 8412. End thermally conductive sheet; 8413. Side thermally conductive sheet.

[0081] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0082] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0083] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0084] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the embodiments of the present application.

[0085] In addition, the technical terms "first," "second," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. In the description of the embodiments of the present application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0086] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0087] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0088] Currently, market developments indicate that battery applications are becoming increasingly widespread. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0089] During the use of battery cells, the temperature difference between the inside and outside is too large, resulting in a decrease in the performance and service life of the battery cells.

[0090] The reason for the above problems is that the internal temperature of the battery cell cannot be quickly transmitted to the outside world, and its internal temperature accumulates and rises, and the electrode assembly is prone to lithium deposition due to excessive temperature; and in a low temperature environment, the external environment is also difficult to heat the electrode assembly, resulting in the battery cell having a capacity and pulse performance reduction due to the low temperature, affecting the performance of the battery cell.

[0091] Based on the above problems, an embodiment of the present application provides a battery cell, which includes a shell, an electrode assembly and a heat-conducting assembly. The electrode assembly is located inside the shell, and the shell provides accommodation and protection for the electrode assembly. The electrode assembly includes an electrode body and a tab. The electrode body includes a first end face and a second end face arranged opposite to each other in a first direction, and a side surface connected between the first end face and the second end face. The electrode body forms a loop with an external component through the tab extending from the first end face and / or the second end face. The heat-conducting assembly includes an insulating member and a heat-conducting member. The insulating member covers at least the side face and is insulated from the shell and at least part of the electrode assembly. The insulating member can replace at least part of the Mylar film to reduce the preparation cost of the battery cell, reduce the thickness of the battery cell, and improve the energy density of the battery cell. At least part of the insulating part forms a receiving cavity, and the heat conductive part is arranged in the receiving cavity. The insulating part can insulate the heat conductive part and the electrode body, and can isolate the heat conductive part and the electrolyte through the insulating part to improve the incompatibility problem between the heat conductive part and the electrolyte. The thermal conductivity of the heat conductive part is greater than the thermal conductivity of the insulating part and the thermal conductivity of the shell. The heat conductive part includes a first heat conductive plate, which is arranged on at least part of the side and is heat-conductively connected to the side. The first heat conductive plate is used to reduce the thermal resistance of the electrode body at its side, improve the temperature uniformity of the electrode body at its side, and improve the rate of heat exchange between the electrode body at its side and the external environment, so as to balance the internal temperature of the battery cell and improve the problem that the performance and service life of the battery cell are adversely affected by the internal temperature of the battery cell being too high or too low.

[0092] The technical solutions described in the embodiments of the present application are applicable to battery devices and electrical devices using battery devices.

[0093] Electrical devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may include fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles may include pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0094] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0095] The battery cells may be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc., and the present invention does not limit this. The battery cells may be cylindrical, flat, rectangular, or other shapes, and the present invention does not limit this.

[0096] The battery device 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 device referred to in this application may include a battery module or battery pack. A battery pack generally includes a casing for enclosing one or more battery cells. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0097] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes 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, with the positive active material layer coated on the surface of the positive current collector. The positive current collector includes a positive current collector portion and a positive electrode tab connected to the positive current collector portion. The positive current collector portion is coated with the positive active material layer, while the positive electrode tab is not coated with the positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, which is coated on the surface of the current collector. The negative current collector includes a negative current collecting portion and a negative electrode tab connected to the negative current collecting portion. The negative current collecting portion is coated with the negative active material layer, while the negative tab is not coated with the negative active material layer. The negative current collector can be made of copper, and the negative active material layer includes a negative active material, which can be carbon or silicon, for example. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene).

[0098] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the battery devices and electrical equipment described above, but can also be applied to all battery devices including a box and electrical equipment using the battery devices. However, for the sake of simplicity, the following embodiments are explained using electric vehicles as an example.

[0099] Please refer to Figure 1 , Figure 1A schematic structural diagram of a vehicle 1 provided for some embodiments of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 2 is provided inside the vehicle 1, and the battery device 2 may be provided at the bottom, head or tail of the vehicle 1. The battery device 2 may be used to power the vehicle 1, for example, the battery device 2 may serve as an operating power source for the vehicle 1. The vehicle 1 may further include a controller 102 and a motor 101, and the controller 102 is used to control the battery to power the motor 101, for example, for starting, navigating and operating power requirements of the vehicle 1 during driving.

[0100] In some embodiments of the present application, the battery device 2 can serve not only 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 .

[0101] Figure 2 A schematic structural diagram of a battery device according to an embodiment of the present application is shown.

[0102] The battery device 2 mentioned in the embodiment of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells 3, and the multiple battery cells 3 are connected in series, parallel or mixed via a busbar.

[0103] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells 3 .

[0104] As an example, the battery cell assembly may be a battery module 201, wherein the battery module 201 is formed by arranging and fixing a plurality of battery cells 3 to form an independent module. As an example, the battery module 201 may be formed by bundling the plurality of battery cells 3 with a cable tie.

[0105] In some embodiments, the battery device may be a battery pack, which includes a case 202 and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case 202 .

[0106] As an example, the battery cell assembly may be a battery module 201 , and the battery cell assembly may be accommodated in the box 202 by fixing the battery module 201 in the box.

[0107] As an example, the battery cell assembly may also be housed in the box body 202 by directly fixing the plurality of battery cells 3 to the box body 202 .

[0108] As an example, housing 202 may include a first housing 2021 and a second housing 2022. The first housing 2021 and the second housing 2022 engage to form an enclosed space within housing 202 for accommodating battery cell assemblies. Enclosed here means covered or closed, and can be either sealed or unsealed. First housing 2021 may be a top cover or a bottom plate.

[0109] As an example, the box body 202 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body 202 to accommodate the battery cell assembly.

[0110] In some embodiments, the box 202 can be used as part of the chassis structure of the vehicle. For example, part of the box 202 can become at least a part of the floor of the vehicle, or part of the box 202 can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0111] Figure 3 A schematic structural diagram of a battery module 201 according to an embodiment of the present application is shown.

[0112] In some embodiments, as Figure 2 and Figure 3 As shown, there are multiple battery cells 3, which are first connected in series, in parallel, or in series to form a battery module 201. The multiple battery modules 201 are then connected in series, in parallel, or in series to form a whole, and are accommodated in a box 202.

[0113] The multiple battery cells 3 in the battery module 201 can be electrically connected via a busbar component to achieve parallel connection, series connection, or mixed connection of the multiple battery cells 3 in the battery module 201 .

[0114] Figure 4 : is an exploded view of a battery cell provided in one embodiment of the present application. Battery cell 3 refers to the smallest unit that constitutes a battery device. Figure 4 The battery cell 3 includes a top cover assembly 6, a shell 4 and an electrode assembly 5.

[0115] The electrode assembly 5 is a component in the battery cell 3 where electrochemical reactions occur. One or more electrode assemblies 5 may be contained in the shell 4. The electrode assembly 5 is mainly formed by winding or stacking electrode sheets, which are divided into positive electrode sheets and negative electrode sheets, and a separator is usually provided between the positive electrode sheets and the negative electrode sheets. The parts of the positive electrode sheets and the negative electrode sheets with active materials constitute the electrode body 52, and the parts of the positive electrode sheets and the negative electrode sheets without active materials each constitute the electrode tab 51. The positive electrode tab and the negative electrode tab may be located together at one end of the electrode body 52 or respectively at both ends of the electrode body 52. ​​During the charge and discharge process of the battery cell 3, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 51 connects the electrode terminals to form a current loop.

[0116] The electrode assembly 5 may be a wound structure, a laminated structure, or a mixed structure of wound and laminated structures.

[0117] In some embodiments, the electrode assembly 5 is a wound structure in which the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0118] In some embodiments, the electrode assembly 5 has a laminated structure. As an example, multiple positive and negative electrode sheets can be provided, and the multiple positive and negative electrode sheets can be alternately stacked. Multiple separators can be provided and respectively disposed between any adjacent positive or negative electrode sheets. Alternatively, the separators can be provided continuously and folded between any adjacent positive or negative electrode sheets.

[0119] In some embodiments, the shape of the electrode assembly 5 can be cylindrical, flat, or polygonal.

[0120] In some embodiments, the electrode assembly 5 is provided with tabs, which can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0121] The battery cell 3 may include a shell. The shell 4 is a component used to cooperate with the top cover assembly 6 to form an internal environment of the battery cell 3, wherein the internal environment formed can be used to accommodate the electrode assembly 5, the electrolyte (not shown in the figure) and other components. The shell 4 can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell) or an aluminum-plastic film, etc. In some embodiments, the shell 4 can be a sealed structure or a non-sealed structure. As an example, when the shell 4 is a non-sealed structure, the shell 4 plays a role in protecting the electrode assembly 5, and a sealing bag is further included between the shell 4 and the electrode assembly 5, which is used to encapsulate the electrode assembly and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film. When the shell 4 is a sealed structure, it is used to encapsulate components such as the electrode assembly 5 and the electrolyte.

[0122] As an example, the battery cell 3 can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, and a polygonal battery. The polygonal battery is, for example, a hexagonal battery, etc. There is no special limitation in this application.

[0123] The housing 4 and the top cover assembly 6 can be separate components. One or more openings 41 can be provided on the housing 4, and one or more top cover assemblies 6 cover the openings 41 to form the internal environment of the battery cell 3. Alternatively, the top cover assembly 6 and the housing 4 can be integrated. Optionally, the top cover assembly 6 and the housing 4 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 4 needs to be enclosed, the top cover assembly 6 can be used to cover the housing 4.

[0124] In some embodiments, the electrode terminal 61 can be provided on the top cover assembly 6 or on the housing 4, and the electrode terminal 61 is electrically connected to the tab 51. The electrode terminal 61 can be directly connected to the tab 51 or indirectly connected to the tab 51 through the adapter 7.

[0125] See also Figure 5 、 Figure 6 、 Figure 7 and Figure 8 , Figure 5 This is a schematic structural diagram of an electrode assembly of a battery cell provided in one embodiment of the present application; Figure 6 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 7 yes Figure 6 Cross-sectional view at AA in the middle; Figure 8 This is an exploded view of a battery cell provided in another embodiment of the present application.

[0126] First, as Figures 4 to 8 As shown, the present application provides a battery cell 3, which includes a shell 4, an electrode assembly 5 and a heat-conducting assembly 8. The electrode assembly 5 is located in the shell 4, and the electrode assembly 5 includes an electrode body 52 and a tab 51. The electrode body 52 includes a first end face 521 and a second end face 522 arranged opposite to each other in a first direction X, and a side face 523 connected between the first end face 521 and the second end face 522. The tab 51 is connected to the electrode body 52 and extends out of at least one of the first end face 521 and the second end face 522; the heat-conducting assembly 8 includes an insulating member 85 and a heat-conducting member 84. At least a portion of the insulating member 85 forms a receiving cavity 851. The heat-conducting member 84 is disposed in the receiving cavity 851. The insulating member 85 at least covers the side face 523. The heat-conducting member 84 includes a first heat-conducting sheet 841. The first heat-conducting sheet 841 is disposed on at least a portion of the side face 523 and is thermally connected to the side face 523. The thermal conductivity of the heat-conducting member 84 is greater than the thermal conductivity of the insulating member 85 and the shell 4.

[0127] In the embodiment of the present application, the battery cell 3 includes a shell 4, an electrode assembly 5 and a heat-conducting assembly 8. The electrode assembly 5 is located inside the shell 4. The shell 4 provides accommodation and protection for the electrode assembly 5. The electrode assembly 5 includes an electrode body 52 and a pole ear 51. The electrode body 52 includes a first end face 521 and a second end face 522 arranged opposite to each other in a first direction X, and a side face 523 connected between the first end face 521 and the second end face 522. The electrode body 52 forms a loop with an external component through the pole ear 51 extending from the first end face 521 and / or the second end face 522. The heat-conducting assembly 8 includes an insulating member 85 and a heat-conducting member 84. The insulating member 85 at least covers the side face 523. The insulating member 85 is insulated from the shell 4 and at least part of the electrode assembly 5. The insulating member 85 can replace at least part of the Mylar film to reduce the preparation cost of the battery cell 3, reduce the thickness of the battery cell 3, and improve the energy density of the battery cell 3. The insulating member 85 at least A accommodating cavity 851 is formed in a partial area, and a heat conducting member 84 is arranged in the accommodating cavity 851. The heat conducting member 84 and the electrode body 52 can be insulated by the insulating member 85, and the heat conducting member 84 and the electrolyte can be isolated by the insulating member 85 to improve the incompatibility problem between the heat conducting member 84 and the electrolyte. The thermal conductivity of the heat conducting member 84 is greater than the thermal conductivity of the insulating member 85 and the thermal conductivity of the shell 4. The heat conducting member 84 includes a first heat conducting plate 841, which is arranged on at least a portion of the side surface 523 and is thermally connected to the side surface 523. The first heat conducting plate 841 is used to reduce the thermal resistance of the electrode body 52 at its side surface 523, improve the temperature uniformity of the electrode body 52 at its side surface 523, and improve the rate of heat exchange between the electrode body 52 at its side surface 523 and the external environment, so as to balance the internal temperature of the battery cell 3 and improve the problem that the performance and service life of the battery cell 3 are adversely affected by the internal temperature of the battery cell 3 being too high or too low.

[0128] The electrode body 52 is formed by winding or stacking a separator, a positive electrode sheet 5241, and a negative electrode sheet 5242. The tabs 51 include a positive tab and a negative tab, each of which extends from the first end face 521 or the second end face 522, or one of which extends from the first end face 521 and the other from the second end face 522.

[0129] Exemplarily, the battery cell 3 also includes a top cover assembly 6 connected to the pole ear 51, the shell 4 includes an end opening 41 close to the first end face 521 or the second end face 522 in the first direction X, the top cover assembly 6 covers the opening 41, the positive pole ear and the negative pole ear extend from the first end face 521 or the second end face 522 and are connected to the top cover assembly 6; or the shell 4 includes two openings 41 opposite to each other along the first direction X, the two top cover assemblies 6 respectively cover the two openings 41, the positive pole ear and the negative pole ear respectively extend from the first end face 521 and the second end face 522 and are connected to the top cover assembly 6.

[0130] Exemplarily, the first direction X is the height direction of the electrode assembly 5 .

[0131] The first heat conducting sheet 841 is thermally connected to the side surface 523 of the electrode body 52 , and heat can be conducted between the first heat conducting sheet 841 and the side surface 523 of the electrode body 52 through the insulating member 85 .

[0132] During the operation of the battery cell 3, the heat generated by the electrode body 52 can be transferred to the external environment through the heat-conducting component 8, thereby improving the problem of damage to the electrode body 52 caused by excessive temperature; or in a low-temperature environment, the heat-conducting component 8 can conduct external heat to the electrode body 52 to heat the electrode assembly 5.

[0133] Optionally, the battery device 2 includes a heat exchange mechanism, the outer shell of the battery cell 3 is thermally connected to the heat exchange mechanism, the heat conducting component 8 can conduct heat between the heat exchange mechanism and the electrode assembly 5, and the heat exchange mechanism can import or export heat to the heat conducting component 8.

[0134] For example, the heat exchange mechanism may be provided on a water-cooling plate or a phase-change heat sink on the outer surface of the battery cell 3 or in a cavity containing a heat exchange medium.

[0135] For example, the insulating member 85 may be made of PP or PI (polyimide) or PET (polyethylene terephthalate), etc. The thermal conductive member 84 may be made of graphite, graphene, or carbon nanotubes, etc.

[0136] Optionally, the heat conducting member 84 is arranged in the accommodating cavity 851, and the area of ​​the heat conducting member 84 matches the area of ​​the accommodating cavity 851. The area of ​​the accommodating cavity 851 can be smaller than the area of ​​the insulating member 85. The heat conducting member 84 contacts the cavity wall of the accommodating cavity 851, and the accommodating cavity 851 serves to limit the heat conducting member 84.

[0137] Optionally, the heat conducting member 84 may be plate-shaped or mesh-shaped, and for example, a mesh-shaped heat conducting member or one or more spaced plate-shaped heat conducting members are provided in the accommodating cavity 851. The heat conducting member 84 may be rectangular, circular, or diamond-shaped, for example.

[0138] Illustratively, multiple first heat conducting sheets 841 are spaced apart in the accommodating cavity 851 , which can conduct heat from the side surface 523 through the first heat conducting sheets 841 with a larger area, while reducing the overall size of the heat conducting member 84 and lowering the manufacturing cost of the battery cell 3 .

[0139] Optionally, during the operation of the electrode assembly 5, the temperature of the end of the electrode body 52 close to the pole ear 51 is relatively higher, and the temperature of the end away from the pole ear 51 is relatively lower. The first heat conductive plate 841 arranged on the side 523 of the electrode body 52 can conduct and balance the temperature of the electrode assembly 5 in the first direction X.

[0140] Optionally, in the first direction X, the accommodating cavity 851 and the first heat conducting sheet 841 extend to both ends of the electrode body 52 .

[0141] Optionally, the accommodating cavity 851 and the first thermally conductive sheet 841 cover the entire side surface 523 of the electrode body 52 to improve the thermal conductivity of the thermally conductive assembly 8. Optionally, an insulating member 85 covers the entire side surface 523. The insulating member 85 serves to insulate the electrode assembly 5 and the housing 4. The insulating member 85 can replace part or all of the Mylar film, so that the battery cell 3 is provided with a smaller Mylar film or no Mylar film is required, thereby reducing the production cost of the battery cell 3, reducing the thickness of the battery cell 3, and improving the energy density of the battery cell 3.

[0142] Exemplarily, the tabs 51 extend from both ends of the electrode body 52 in the first direction X, and the insulating member 85 covering the side surface 523 can completely replace the Mylar film.

[0143] It should be noted that the heat conductor 84 is located inside the insulating member 85 and is covered by the insulating member 85 . In order to conveniently illustrate the position of the heat conductor 84 in the drawings, the shadow on the insulating member 85 is used to represent the heat conductor 84 .

[0144] Optionally, the insulating member 85 is provided with a accommodating cavity 851 with an opening at one end, the heat conductive member 84 is arranged in the accommodating cavity 851, and is bonded or welded to the opening of the insulating member 85 so that the heat conductive member 84 is located in a sealed accommodating cavity 851; or the two ends of the insulating member 85 are folded in half, the heat conductive member 84 is located between the two ends of the insulating member 85, and the two ends of the insulating member 85 are bonded or welded together so that the heat conductive member 84 is located in a sealed accommodating cavity 851; or the insulating member 85 includes two sub-insulating layers 855 arranged opposite to each other, and the edges of the two sub-insulating layers 855 are bonded or welded so that the heat conductive member 84 is located in a sealed accommodating cavity 851.

[0145] Optionally, an adhesive layer is provided on the side of the insulating member 85 facing the electrode body 52 to bond the heat conducting component 8 to the electrode body 52. ​​For example, the adhesive layer can be an insulating colloid to enhance the insulation performance of the heat conducting component 8 and the electrode assembly 5.

[0146] Optionally, the insulating member 85 and the Mylar film are connected to each other, and the insulating member 85 and the Mylar film jointly cover the second end face 522 and the side face 523 of the electrode body 52, or the insulating member 85 and the Mylar film jointly cover the side face 523 of the electrode body 52. ​​The combination of the Mylar film and the insulating member 85 is used to achieve insulation between the electrode body 52 and the shell 4, which helps to reduce the size of the Mylar film and reduce the preparation cost of the battery cell 3, and helps to reduce the thickness of the battery cell 3 and improve the energy density of the battery cell 3.

[0147] The side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232. The two first side surfaces 5231 are arranged opposite to each other in the second direction Y, and the two second side surfaces 5232 are arranged opposite to each other in the third direction Z. The first direction X, the second direction Y and the third direction Z intersect with each other, and the area of ​​the first side surface 5231 is greater than the area of ​​the second side surface 5232.

[0148] The insulating member 85 and the Mylar film are connected by bonding or welding. The specific dimensions of the insulating member 85 and the Mylar film can be flexibly designed. For example, the insulating member 85 covers the first side surface 5231 and the second end surface 522, and the Mylar film covers the second side surface 5232; or the insulating member 85 covers the side surface 523, and the Mylar film covers the second end surface 522.

[0149] See also Figure 9 , Figure 9 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0150] In some embodiments, as Figure 5 and Figure 9 As shown, the electrode tab 51 extends out of the first end surface 521 , and the insulating member 85 covers the second end surface 522 and the side surface 523 of the electrode body 52 .

[0151] In these embodiments, the insulating member 85 covers the second end face 522 and the side face 523 of the electrode body 52 to insulate the shell 4 and the electrode assembly 5, and no Mylar film is required, which helps to reduce the segmented preparation cost of the battery cell 3, and can reduce the thickness of the battery cell 3 and improve the energy density of the battery cell 3.

[0152] In the embodiment of the present application, the housing 4 and the electrode assembly 5 are insulated by an insulating member 85, and a Mylar film is not required, or the insulating member 85 replaces at least part of the Mylar film. The thermal conductivity of the insulating member 85 and the Mylar film is similar, so in the embodiment of the present application, replacing the Mylar film with the insulating member 85 does not significantly affect the heat dissipation of the electrode assembly 5; a heat conductor 84 is provided within the insulating member 85, and the thermal conductivity of the heat conductor 84 is greater than the thermal conductivity of the Mylar film. Therefore, compared with the case where the insulating member 85 or the Mylar film is provided between the electrode assembly 5 and the housing 4, the heat conductor 84 is provided between the electrode assembly 5 and the housing 4. The heat conductor 84 can improve the heat conduction rate between the electrode assembly 5 and the external environment, that is, the heat conduction efficiency between the electrode assembly 5 and the external environment can be improved by the heat conductor 84.

[0153] The thermal conductivity of the heat conducting assembly 8 can be measured by heat flow method, hot plate method, hot wire method, etc. When performing thermal conductivity test on the heat conducting assembly 8, the test sample of the heat conducting assembly 8 should include a heat conducting member 84 and an insulating member 85 covering the outer surface of the heat conducting member 84.

[0154] By combining the insulating member 85 and the heat conducting member 84 , the insulating member 85 can achieve insulation between the electrode body 52 and the shell 4 , while also achieving insulation between the heat conducting member 84 and the electrode body 52 , and isolating the heat conducting member 84 from the electrolyte.

[0155] The insulating member 85 covers the second end surface 522 and side surface 523 of the electrode body 52. ​​The insulating member 85 can replace the Mylar film, eliminating the need for a separate Mylar film for the battery cell 3. The dimensions of the thermal conductor 84 within the accommodating cavity 851 can be customized. For example, the thermal conductor 84 covers at least one of the first side surface 5231, the second side surface 5232, and the second end surface 522 to enhance the thermal conductor 84's ability to conduct heat between the electrode assembly 5 and the external environment.

[0156] See also Figure 10 、 Figure 11 and Figure 12 , Figure 10 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 11 This is an expanded view of a thermally conductive component of a battery cell provided in one embodiment of the present application; Figure 12 Schematic diagram of the structure of a heat-conducting component of a battery cell provided in one embodiment of the present application.

[0157] In some embodiments, as Figure 5 、 Figures 10 to 12As shown, the side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232, the two first side surfaces 5231 are arranged opposite to each other in the second direction Y, and the two second side surfaces 5232 are arranged opposite to each other in the third direction Z, the first direction X, the second direction Y and the third direction Z intersect each other, the area of ​​the first side surface 5231 is greater than the area of ​​the second side surface 5232, the insulating member 85 includes a first insulating portion 852, the first insulating portion 852 includes a main body portion 8521 and a bending portion 8522 connected to each other, the main body portion 8521 and the bending portion 8522 are connected, the main body portions 8521 of the two first insulating portions 852 are respectively arranged on the two first side surfaces 5231, and the two bending portions 8522 are respectively arranged on the two second side surfaces 5232, and the first heat conducting plate 841 is arranged on at least one of the main body portion 8521 and the bending portion 8522.

[0158] In these embodiments, the first insulating part 852 includes a main body part 8521 and a bending part 8522 that are connected to each other, the main body part 8521 and the bending part 8522 are connected, the main bodies of the two first insulating parts 852 are respectively arranged on the two first side surfaces 5231, and the two bending parts 8522 are respectively arranged on the two second side surfaces 5232 to achieve insulation of the electrode assembly 5 on its peripheral side surface and the shell 4, and the first thermal conductive sheet 841 is arranged on at least one of the main body part 8521 and the bending part 8522 to improve the thermal conductivity rate at the first side surface 5231 and / or the second side surface 5232 of the electrode assembly 5.

[0159] The first heat conducting sheet 841 may be disposed on at least one of the main body portion 8521 and the bent portion 8522 .

[0160] In the same shell 4 , the insulating member 85 includes two first insulating portions 852 , and the two first insulating portions 852 , which are arranged opposite to each other, cover at least a portion of the outer circumferential surface of the electrode assembly 5 .

[0161] like Figure 11 As shown, the first insulating part 852 includes a main body part 8521 and a bending part 8522 that are interconnected. The main body part 8521 and the bending part 8522 are integrally formed to improve the structural strength of the first insulating part 852. There is a fold line between the main body part 8521 and the bending part 8522. The main body part 8521 covers the first side surface 5231, and the bending part 8522 is bent along the fold line and covers the second side surface 5232, or the main body part 8521 and the bending part 8522 are prepared separately, and the main body part 8521 and the bending part 8522 are bonded or welded together.

[0162] The first insulating portion 852 includes a main body 8521 and a bent portion 8522 connected to one end of the main body 8521 in the third direction Z. The main body 8521 covers a first side surface 5231 of the electrode assembly 5. One end of the bent portion 8522 is connected to the main body 8521, and the other end extends along the second direction Y toward the main body 8521 of another first insulating portion 852. The bent portion 8522 is connected to two main bodies 8521, or the bent portion 8522 and the main body 8521 are spaced apart and connected by a Mylar film.

[0163] Alternatively, the first insulating part 852 includes a main body part 8521 and a bending part 8522 connected to the two ends of the main body part 8521 in the third direction Z, the main body part 8521 covers the first side surface 5231 of the electrode assembly 5, and the bending parts 8522 of the two oppositely arranged first insulating parts 852 extend relative to each other in the second direction Y and are connected to each other, or the bending parts 8522 of the two oppositely arranged first insulating parts 852 extend relative to each other in the second direction Y, and the two bending parts 8522 are connected by a Mylar film.

[0164] Optionally, in the same shell 4 , the insulating member 85 includes two first insulating portions 852 , which are integrally formed and surround the outer peripheral surface of the electrode assembly 5 .

[0165] Optionally, the main body 8521 covers the first side surface 5231 of the electrode assembly 5 , and the bent portion 8522 covers the second side surface 5232 of the electrode assembly 5 , so that the first insulating portion 852 can reliably insulate the electrode assembly 5 and the shell 4 .

[0166] Optionally, the heat conducting member 84 is provided on the entire main body portion 8521 or the bending portion 8522 ; or a plurality of heat conducting members 84 are provided at intervals on the main body portion 8521 or the bending portion 8522 .

[0167] Optionally, a plurality of electrode assemblies 5 are provided, the main body 8521 is provided between the shell 4 and the first side surface 5231 closest to the shell 4 , and the bending portion 8522 is provided on one or more second side surfaces 5232 .

[0168] See also Figure 13 and Figure 14 , Figure 13 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 14 This is a partial structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application.

[0169] In some embodiments, as Figure 13 and Figure 14 As shown, a first through hole 815 is provided through the first insulating portion 852 , and the first through hole 815 and the accommodating cavity 851 are spaced apart.

[0170] In these embodiments, a first through hole 815 is provided through the first insulating portion 852 so that the electrolyte can penetrate the electrode assembly 5 through the first through hole 815 . The first through hole 815 and the accommodating cavity 851 are spaced apart to avoid contact between the electrolyte and the first thermal conductive plate 841 .

[0171] The accommodating cavity (not shown) is provided in a portion of the first insulating portion 852, the first thermally conductive sheet 841 is provided in the accommodating cavity 851, and the first through-hole 815 extends through another portion of the first insulating portion 852. The first through-hole 815 and the accommodating cavity 851 are not connected. Thus, when the electrolyte penetrates the electrode assembly 5 through the first through-hole 815, the electrolyte does not enter the accommodating cavity 851 and contact the first thermally conductive sheet 841, and the insulating member 85 can still maintain the insulation between the first thermally conductive sheet 841 and the electrode assembly 5. The specific shape and size of the first through-hole 815 can be designed voluntarily. For example, the first through-hole 815 is a circular hole or a rectangular hole.

[0172] Exemplarily, the insulating member 85 is molded to form the accommodating cavity 851 , and the first through hole 815 can be disposed in the molding area 856 , or the first through hole 815 can be disposed on a side of the molding area 856 away from the accommodating cavity.

[0173] See also Figure 15 and Figure 16 , Figure 15 This is a partial structural diagram of a heat-conducting component of a battery cell provided in another embodiment of the present application; Figure 16 It is a partial structural diagram of a heat-conducting component of a battery cell provided in another embodiment of the present application.

[0174] In some embodiments, as Figure 15 and Figure 16 As shown, a first avoidance hole 8414 is provided through the first heat conducting plate 841 , the first insulating portion 852 covers the inner wall of the first avoidance hole 8414 , a first through hole 815 is provided through the first insulating portion 852 , and the first through hole 815 is located in the first avoidance hole 8414 .

[0175] In these embodiments, a first avoidance hole 8414 is provided through the first thermal conductive sheet 841, and a first through hole 815 is provided through the first insulating portion 852. The first through hole 815 is located in the first avoidance hole 8414 so that the electrolyte can penetrate into the electrode assembly 5 through the first through hole 815 and the first avoidance hole 8414. The first insulating portion 852 covers the inner wall of the first avoidance hole 8414 to prevent the electrolyte from contacting the first thermal conductive sheet 841 and to keep the first thermal conductive sheet 841 and the electrode assembly 5 insulated.

[0176] A first avoidance hole 8414 is provided on the first heat conducting sheet 841, and a first through-hole 815 is provided on the first insulating portion 852. The first through-hole 815 is located within the first avoidance hole 8414, or in other words, the orthographic projection of the first avoidance hole 8414 in the thickness direction of the insulating member 85 is located within the first through-hole 815. This allows the electrolyte to penetrate the electrode assembly 5 through the first through-hole 815 and the first avoidance hole 8414. The first insulating portion 852 covers the inner wall of the first avoidance hole 8414 and is used to isolate the electrolyte passing through the first through-hole 815 from contact with the inner wall of the first avoidance hole 8414. Furthermore, the first insulating portion 852 insulates the electrode assembly 5 from the inner wall of the first avoidance hole 8414. The shape and size of the first avoidance hole 8414 can be designed arbitrarily. For example, the first avoidance hole 8414 is a circular hole or a rectangular hole.

[0177] Optionally, the first avoidance hole 8414 and the first through hole 815 have the same shape to better match the two. Exemplarily, the first avoidance hole 8414 and the first through hole 815 are both circular holes.

[0178] Exemplarily, the first insulating part 852 is plastic-sealed to form a accommodating cavity 851, the first heat-conducting plate 841 is accommodated in the accommodating cavity, part of the first insulating part 852 is plastic-sealed and connected to the first avoidance hole 8414, the first through hole 815 passes through the plastic-sealed area 856, and the first through hole 815 and the inner wall of the first avoidance hole 8414 are spaced apart by the plastic-sealed area 856.

[0179] See also Figure 17 , Figure 17 Schematic diagram of the structure of a heat-conducting component of a battery cell provided in one embodiment of the present application.

[0180] In some embodiments, as Figure 5 、 Figure 9 and Figure 17 As shown, the electrode ear 51 extends out of the first end face 521, and the insulating member 85 also includes a second insulating portion 853, which is arranged between the second end face 522 of the electrode body 52 and the shell 4. The second insulating portion 853 is insulated from the shell 4 and the second end face 522 of the electrode assembly 5, and the main body portions 8521 of the two first insulating portions 852 are respectively connected to the two sides of the second insulating portion 853.

[0181] In these embodiments, the insulating part 85 also includes a second insulating part 853 arranged between the second end face 522 of the electrode body 52 and the shell 4, and the main body 8521 of the two first insulating parts 852 are respectively connected to the two sides of the second insulating part 853, thereby reducing the difficulty of aligning the second insulating part 853 and the first insulating part 852, and reducing the difficulty of matching the insulating part 85 and the electrode assembly 5.

[0182] Optionally, the second insulating part 853 and the first insulating part 852 are bonded or welded to facilitate adjustment of the sizes of the second insulating part 853 and the first insulating part 852; or the second insulating part 853 and the first insulating part 852 are integrally formed to reduce the seams of the insulating part 85 and improve the structural stability of the insulating part 85.

[0183] Optionally, the second insulating portion 853 and the first insulating portion 852 are integrally formed, the second insulating portion 853 covers the second end face 522, and then the main body portion 8521 is bent and covers the first side face 5231 of the electrode assembly 5, and then the bent portion 8522 is bent and covers the second side face 5232 of the electrode assembly 5.

[0184] Optionally, a plurality of electrode assemblies 5 are provided, and the second insulating portion 853 is provided along the first direction X between one or more electrode assemblies 5 and the shell 4 .

[0185] In some embodiments, as Figure 9 and Figure 17 As shown, the heat conducting member 84 includes a second heat conducting plate 842 , and the second heat conducting plate 842 is disposed on the second insulating portion 853 .

[0186] In these embodiments, the heat conducting member 84 includes a second heat conducting sheet 842 disposed on the second insulating portion 853 to improve the heat conduction rate at the second end surface 522 .

[0187] Optionally, the orthographic projection of the second heat conducting sheet 842 in the first direction X covers the second end surface 522 of the electrode assembly 5; or there are multiple electrode assemblies 5, and the orthographic projection of the second heat conducting sheet 842 in the first direction X covers the second end surfaces 522 of multiple electrode assemblies 5.

[0188] For example, the size and shape of the second heat conducting plate 842 can be designed independently, and the second heat conducting plate 842 is rectangular or elliptical.

[0189] See also Figure 18 and Figure 19 , Figure 18 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 19 This is a partial structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application.

[0190] In some embodiments, as Figures 17 to 19 As shown, a second through hole 821 is provided through the second insulating portion 853 , and the second through hole 821 and the accommodating cavity 851 are spaced apart.

[0191] In the technical solution of the embodiment of the present application, a second through hole 821 is provided through the second insulating part 853 so that the electrolyte can infiltrate the electrode assembly 5 through the second through hole 821. The second through hole 821 and the accommodating cavity 851 are spaced apart to avoid contact between the electrolyte and the second thermal conductive plate 842.

[0192] The accommodating cavity 851 is disposed within a portion of the second insulating portion 853 , the second thermally conductive sheet 842 is disposed within the accommodating cavity 851 , and the second through-hole 821 extends through another portion of the second insulating portion 853 . The second through-hole 821 and the accommodating cavity 851 are not connected. Thus, when the electrolyte penetrates the electrode assembly 5 through the first through-hole 815 , the electrolyte does not enter the accommodating cavity 851 and contact the second thermally conductive sheet 842 , and the insulating member 85 can still insulate the second thermally conductive sheet 842 from the electrode assembly 5 . The specific shape and size of the second through-hole 821 can be designed arbitrarily. For example, the second through-hole 821 is a circular hole or a rectangular hole.

[0193] Exemplarily, the insulating member 85 is molded to form the accommodating cavity 851 , and the second through hole 821 can be disposed in the molding area 856 , or the second through hole 821 can be disposed on a side of the molding area 856 away from the accommodating cavity.

[0194] See also Figure 20 and Figure 21 , Figure 20 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 21 It is a partial structural diagram of a heat-conducting component of a battery cell provided in another embodiment of the present application.

[0195] In some embodiments, as Figure 20 and Figure 21 As shown, a second avoidance hole 8421 is provided through the second heat conducting plate 842 , the second insulating portion 853 covers the inner wall of the second avoidance hole 8421 , a second through hole 821 is provided through the second insulating portion 853 , and the second through hole 821 is located inside the second avoidance hole 8421 .

[0196] In the technical solution of the embodiment of the present application, a second avoidance hole 8421 is provided through the second heat conducting plate 842, and a second through hole 821 is provided through the second insulating portion 853. The second through hole is located in the second avoidance hole 8421, so that the electrolyte can pass through the second through hole 821 and the second avoidance hole 8421 and infiltrate the electrode assembly 5. The second insulating portion 853 covers the inner wall of the second avoidance hole 8421 to avoid contact between the electrolyte and the second heat conducting plate 842, and to keep the second heat conducting plate 842 and the electrode assembly 5 insulated.

[0197] A second avoidance hole 8421 is provided on the second heat conducting sheet 842, and a second through-hole 821 is provided on the insulating member 85. The second through-hole 821 is located within the second avoidance hole 8421, or in other words, the orthographic projection of the second avoidance hole 8421 in the thickness direction of the insulating member 85 is located within the second through-hole 821. This allows the electrolyte to penetrate the electrode assembly 5 through the second through-hole 821 and the second avoidance hole 8421. A second insulating portion 853 covers the inner wall of the second avoidance hole 8421. The second insulating portion 853 is used to prevent the electrolyte passing through the second through-hole 821 from contacting the inner wall of the second avoidance hole 8421 of the second heat conducting member 84. The second insulating portion 853 also insulates the electrode assembly 5 from the second avoidance hole 8421. The shape and size of the second avoidance hole 8421 can be designed arbitrarily. For example, the second avoidance hole 8421 is a circular hole or a rectangular hole.

[0198] Optionally, the second avoidance hole 8421 and the second through hole 821 have the same shape to facilitate better coordination between the two.

[0199] Exemplarily, the insulating member 85 is plastic-sealed to form a housing cavity 851, the second heat conducting plate 842 is accommodated in the housing cavity, part of the insulating member 85 is plastic-sealed and connected to the second avoidance hole 8421, the second through hole 821 passes through the plastic-sealed area 856, and the inner wall of the second through hole 821 and the second avoidance hole 8421 are spaced apart by the plastic-sealed area 856.

[0200] See also Figure 22 and Figure 23 , Figure 22 This is a schematic structural diagram of a heat-conducting component of a battery cell provided in one embodiment of the present application; Figure 23 This is an expanded view of a thermally conductive component of a battery cell provided in one embodiment of the present application.

[0201] In some embodiments, as Figure 9 、 Figure 22 and Figure 23 As shown, a plurality of electrode assemblies 5 are provided, and the plurality of electrode assemblies 5 are stacked along the second direction Y. The insulating member 85 also includes a middle insulating portion 854, which is provided between the electrode bodies 52 of adjacent electrode assemblies 5. The middle insulating portion 854 and the second insulating portion 853 are connected to each other, and the first thermal conductive plate 841 includes an intermediate thermal conductive plate 8411, which is provided in the middle insulating portion 854.

[0202] In these embodiments, the middle insulating portion 854 is arranged between adjacent electrode bodies 52 to insulate the adjacent electrode bodies 52, the middle insulating portion 854 and the second insulating portion 853 are interconnected to improve the insulation reliability of the middle insulating portion 854, and the intermediate thermal conductive plate 8411 is arranged in the middle insulating portion 854 to improve the thermal conductivity between adjacent electrode bodies 52.

[0203] The first heat conducting plate 841 also includes an end heat conducting plate 8412 and a side heat conducting plate 8413. The middle heat conducting plate 8411 is arranged in the middle insulating portion 854 to improve the thermal conductivity between adjacent electrode bodies 52; the end heat conducting plate 8412 is arranged in the main body portion 8521 to improve the thermal conductivity of the adjacent first side surface 5231; the side heat conducting plate 8413 is arranged in the bending portion 8522 to improve the thermal conductivity of the adjacent second side surface 5232.

[0204] Optionally, the middle insulating part 854 and the second insulating part 853 are connected by bonding or welding, or the middle insulating part 854 and the second insulating part 853 are integrally formed to improve the connection stability between the middle insulating part 854 and the second insulating part 853.

[0205] Optionally, the middle insulating portion 854 , the second insulating portion 853 , and the bent portion 8522 are connected, so that the insulating member 85 can be wrapped around the circumferential side surface and the second end surface 522 of the electrode body 52 .

[0206] Exemplarily, if there are multiple electrode assemblies 5, the electrode body 52 is located between the second insulating part 853, the middle insulating part 854, the main body 8521 and the bending part 8522; or the electrode body 52 is located between the second insulating part 853, the two middle insulating parts 854 and the two bending parts 8522; or if there is only one electrode assembly 5, the electrode body 52 is located between the second insulating part 853, the two bending parts 8522 and the two main bodies 8521.

[0207] In some embodiments, as Figure 9 、 Figure 22 and Figure 23 As shown, the first heat conducting plate 841 and the second heat conducting plate 842 are connected to each other.

[0208] In these embodiments, the heat conducting member 84 includes a second heat conducting plate 842 arranged on the second insulating portion 853, and the first heat conducting plate 841 and the second heat conducting plate 842 are connected to each other so that the heat between adjacent electrode assemblies 5 can be transferred to the second heat conducting plate 842 through the first heat conducting plate 841 and exchange heat with the external environment, thereby improving the thermal conductivity rate of the heat conducting assembly 8.

[0209] Optionally, the intermediate heat conducting plate 8411 and the second heat conducting plate 842 are connected to each other. For example, the second insulating part 853 is provided with a first connecting hole toward the middle insulating part 854, and the middle insulating part 854 is provided with a second connecting hole toward the second insulating part 853. The first heat conducting plate 841 of the middle insulating part 854 is connected to the second heat conducting plate 842 through the first connecting hole and the second connecting hole.

[0210] Optionally, the end heat conducting plate 8412 and the second heat conducting plate 842 are connected to each other. For example, the second insulating part 853 is provided with a third connecting hole toward the main body part 8521, and the main body part 8521 is provided with a fourth connecting hole toward the second insulating part 853. The end heat conducting plate 8412 is provided in the main body part 8521, and the end heat conducting plate 8412 is connected to the second heat conducting plate 842 through the third connecting hole and the fourth connecting hole.

[0211] Optionally, the side heat conducting sheet 8413 and the second heat conducting sheet 842 are connected to each other. For example, the second insulating portion 853 is provided with a fifth connecting hole toward the bending portion 8522, and the bending portion 8522 is provided with a sixth connecting hole toward the second insulating portion 853. The side heat conducting sheet 8413 is provided in the bending portion 8522, and the side heat conducting sheet 8413 is connected to the second heat conducting sheet 842 through the fifth connecting hole and the sixth connecting hole.

[0212] Optionally, the second heat conducting sheet 842 and the first heat conducting sheet 841 provided on the middle insulating portion 854 are integrally formed to improve the heat conduction efficiency of the heat conducting component 8 .

[0213] In some embodiments, as Figure 8 、 Figure 9 and Figure 10 As shown, the main body 8521 is connected to a bending portion 8522 on both sides of the third direction Z, and the two bending portions 8522 of the two first insulating portions 852 and located on the same side of the electrode assembly 5 extend toward each other in the second direction Y.

[0214] In these embodiments, the main body 8521 is connected to a bending portion 8522 on both sides of the third direction Z, and the two bending portions 8522 of the two first insulating portions 852 and located on the same side of the electrode assembly 5 extend toward each other in the second direction Y. The joint of the two bending portions 8522 is located on the second side surface 5232, and the first side surface 5231 with a larger area can be provided with a larger area of ​​the heat conducting member 84 to improve the thermal conductivity of the heat conducting assembly 8.

[0215] Optionally, the two bent portions 8522 of the two first insulating portions 852 extend toward each other in the second direction Y, and are spaced apart or abut against each other in the second direction Y, so that the main body 8521 can cover the entire first side surface 5231, and the heat conducting member 84 can cover the entire first side surface 5231 to improve the heat conduction efficiency of the heat conducting component 8; or the two bent portions 8522 of the two first insulating portions 852 extend toward each other in the second direction Y and overlap with each other, then the overlapping part of the bent portions 8522 in the third direction Z will not increase the size of the battery cell 3 in the second direction.

[0216] For example, the bent portions 8522 of the two first insulating portions 852 are bent and connected to each other. The insulating member 85 is connected by two sub-insulating layers 855, which are connected at the body portion 8521 to form a receiving cavity 851 (not shown). Each bent portion 8522 includes two sub-insulating layers 855. For ease of understanding in the figure, some sub-insulating layers 855 are folded and some are unfolded.

[0217] Optionally, the two bending portions 8522 connected on both sides of the main body 8521 have the same size and shape to reduce the difficulty of processing the first insulating portion 852. The specific size and shape of the bending portion 8522 can be designed by yourself. For example, the bending portion 8522 is rectangular.

[0218] In some embodiments, as Figure 8 、 Figure 9 and Figure 10 As shown, the two bending portions 8522 extend toward each other in the second direction Y, and the two bending portions 8522 at least partially overlap in the third direction Z.

[0219] In these embodiments, the two bending portions 8522 extend toward each other in the second direction Y, and the two bending portions 8522 at least partially overlap in the third direction Z to improve the insulation reliability of the first insulating portion 852 between the electrode assembly 5 and the shell 4.

[0220] Optionally, the overlapping region of the two bent portions 8522 extends to both ends of the electrode body 52 in the first direction X to improve the insulation reliability of the first insulating portion 852 between the electrode assembly 5 and the housing 4. The shape of the overlapping region of the two bent portions 8522 can be designed arbitrarily. For example, the overlapping region is rectangular.

[0221] Optionally, the two bending portions 8522 are bonded or plastic-sealed in the overlapping area to improve the connection reliability of the bending portions 8522 .

[0222] Optionally, the sum of the extension dimensions of the two bending portions 8522 in the second direction Y is L 11 , the size of the electrode assembly 5 in the second direction Y is L2, which satisfies the following conditions: L2<L11 , so that the two bent portions at least partially overlap in the third direction Z. For example, L 11 The difference from L2 is between 5mm and 10mm, which can save material costs and improve connection reliability;

[0223] The extension dimension of the bent portion 8522 in the second direction Y is L1, and the dimension of the electrode assembly 5 in the second direction Y is L2, satisfying L1=L2, thereby increasing the overlapping area of ​​the two bent portions 8522 and improving the insulation reliability of the bent portion 8522 on the third side surface 523 of the electrode body 52;

[0224] The extension dimension of the bent portion 8522 in the second direction Y is L1, and the dimension of the electrode assembly 5 in the second direction Y is L2, satisfying the condition L2 / 2<L1<L2. Even if there is a partial dimensional error in the bent portion 8522, it does not affect the partial overlap of the two bent portions 8522 in the third direction Z.

[0225] The extension dimension of the bending portion 8522 in the second direction Y is L1, and the dimension of the electrode assembly 5 in the second direction Y is L2 satisfying L2 / 2=L1, so that the two bending portions 8522 of the two oppositely arranged first insulating portions 852 abut against each other, so that the bending portion 8522 can be covered on the third side surface 523 of the electrode body 52 without increasing the dimension of the heat-conducting component 8 in the third direction Z, which helps to improve the energy density of the battery cell 3; each bending portion 8522 has the same size to reduce the processing difficulty of the first insulating portion 852.

[0226] In some embodiments, as Figure 7 、 Figure 9 and Figure 12 As shown, the shell 4 includes an opening 41 in the first direction X, and the battery cell 3 also includes a top cover assembly 6, which covers the opening 41 and is connected to the pole ear 51, and at least one main body portion 8521 extends from the first end surface 521 in the first direction X and is connected to the top cover assembly 6.

[0227] In these embodiments, at least one main body portion 8521 extends from the first end surface 521 in the first direction X and is connected to the top cover assembly 6. The top cover assembly 6 serves to position and fix the thermal conductive assembly 8, thereby improving the stability of the thermal conductive assembly 8 in the shell 4.

[0228] The main body 8521 extends out of the first end surface 521 and is welded to the lower plastic of the top cover assembly 6. The first heat conducting plate 841 is thermally connected to the side surface 523. The first heat conducting plate 841 does not extend beyond the first end surface 521. This can reduce the risk of damage to the first heat conducting plate 841 and reduce the material cost of the heat conducting assembly 8.

[0229] Optionally, both main body portions 8521 are connected to the top cover assembly 6 to enhance the connection stability between the insulating member 85 and the top cover assembly 6 .

[0230] Optionally, the main body 8521 includes a contact section and a welding section, the contact section contacts the side 523 of the electrode body 52, one end of the welding section is connected to the contact section, and the other end extends out of the first end face 521 and is connected to the top cover assembly 6, and the size of the welding section in the third direction Z is greater than or equal to the size of the contact section to improve the connection reliability between the insulating member 85 and the top cover assembly 6.

[0231] In some embodiments, as Figure 9 and Figure 12 As shown, the main body 8521 extends out of the first end surface 521 in the first direction X by a dimension L3 ≥ 2 mm.

[0232] In these embodiments, when the above conditions are met, the connection reliability between the heat conducting component 8 and the top cover component 6 is improved.

[0233] Optionally, a dimension L3 of the main body portion 8521 extending out of the first end surface 521 in the first direction X satisfies 2 mm ≤ L3 ≤ 7 mm, so as to reduce the risk of interference between the excessively long main body portion 8521 and other components.

[0234] Exemplarily, a dimension L3 of the main body portion 8521 extending out of the first end surface 521 in the first direction X is 2 mm, 3 mm, 5 mm, 7 mm, etc.

[0235] In some embodiments, as Figure 7 and Figure 8 As shown, the minimum distance D2 from the orthographic projection of the heat-conducting member 84 in the thickness direction of the heat-conducting component 8 to the edge of the orthographic projection of the insulating member 85 in the thickness direction of the heat-conducting component 8 is greater than or equal to 2 mm.

[0236] In these embodiments, the minimum distance D2 from the edge of the orthographic projection of the thermal conductive member 84 in the thickness direction of the thermal conductive component 8 to the orthographic projection of the insulating member 85 in the thickness direction of the thermal conductive component 8 is greater than or equal to 2 mm, so that there is a sufficient plastic sealing area between the edge of the thermal conductive member 84 and the insulating member 85 to improve the sealing reliability of the accommodating cavity 851.

[0237] Exemplarily, the minimum distance D2 from the heat conducting member 84 to the edge of the insulating member 85 is 2 mm, 3 mm, 5 mm, etc.

[0238] Optionally, the insulating member 85 includes two sub-insulating layers 855 , which are stacked and connected by plastic sealing or bonding in the length and width directions to form an accommodating cavity 851 for accommodating the thermal conductor 84 , and the minimum distance from the thermal conductor 84 to the edge of the sub-insulating layer 855 is greater than or equal to 2 mm;

[0239] Alternatively, the insulating part 85 includes two sub-insulating layers 855 that are integrally formed and connected to each other. The two sub-insulating layers 855 are folded towards each other, and then the edges of their length or width are sealed to form a accommodating cavity 851. The minimum distance from the edge of the thermal conductor 84 to the sub-insulating layer 855 that needs to be sealed or bonded is greater than or equal to 2 mm.

[0240] Optionally, the areas of the two sub-insulating layers 855 are different, and the sub-insulating layer 855 with a smaller area is hot-melt connected to the sub-insulating layer 855 with a larger area to form a accommodating cavity 851. This can not only reduce the volume of the insulating part 85 and reduce the cost of the insulating part 85, but also reduce the volume of the thermal conductive component 8 and improve the energy density of the battery cell 3.

[0241] In some embodiments, as Figure 7 and Figure 8 As shown, the thickness D3 of the heat conducting member 84 satisfies 40 μm≤D3≤180 μm.

[0242] In these embodiments, when the above conditions are met, the problem of excessively thick heat conductor 84 leading to excessive volume of battery cell 3 and reduced energy density can be improved, and the problem of easy damage of heat conductor 84 due to excessive thinness can also be improved.

[0243] Exemplarily, the thickness D3 of the heat-conducting component 8 is 40 μm, 50 μm, 110 μm, 180 μm, etc.

[0244] In some embodiments, as Figure 7 and Figure 8 As shown, the insulating member 85 includes two sub-insulating layers 855 , which are stacked and connected to each other to form a receiving cavity 851 . The thickness D1 of the sub-insulating layer 855 satisfies 5 μm≤D1≤100 μm.

[0245] In these embodiments, when the above conditions are met, the problem of excessive thickness of the sub-insulating layer 855 leading to excessive volume of the battery cell 3 and reduced energy density can be solved, and the problem of easy damage of the sub-insulating layer 855 due to its thinness can also be solved.

[0246] Illustratively, the thickness D1 of the sub-insulating layer 855 is 5 μm, 10 μm, 50 μm, 100 μm, etc.

[0247] Optionally, the two sub-insulating layers 855 have the same thickness to reduce the difficulty of processing the insulating member 85 .

[0248] In some embodiments, as Figure 7 and Figure 8 As shown, the insulating member 85 includes polyethylene or polypropylene or polyimide or polyester resin.

[0249] In these embodiments, the insulating member 85 includes polyethylene, polypropylene, polyimide, or polyester resin to improve the insulation reliability of the insulating member 85 .

[0250] Optionally, the insulating member 85 should have insulating and high temperature resistant properties, so that the insulating member 85 can be used to insulate the thermal conductor 84 and the electrode assembly 5, and reduce the risk of the insulating member 85 melting and being damaged under high temperature conditions.

[0251] In some embodiments, as Figure 7 As shown, the heat conductor 84 includes graphite, graphene, or carbon nanotubes.

[0252] In these embodiments, graphite is typically composed of parallel layers of carbon atoms, exhibiting a planar sheet-like morphology. Graphene is typically a two-dimensional crystal composed of carbon atoms, with only one side atom thick, and has a fibrous shape. Carbon nanotubes are typically tubular structures formed by curling one or more layers of graphite. The material of the heat conductor 84 includes graphite, graphene, or carbon nanotubes, and the thermal conductivity of the heat conductor 84 is improved by using the graphite, graphene, or carbon nanotube thermal conductive material.

[0253] Optionally, the heat conducting member 84 is made of supercrystalline graphite, whose formed grain size is larger than that of ordinary graphite and whose thermal conductivity is significantly improved compared with ordinary graphite, so that the heat conducting member 84 has better thermal conductivity.

[0254] Optionally, heat conductor 84 utilizes graphite heat conduction technology, a heat conduction technology based on graphite materials and microporous structures. The principle is that the efficient thermal conductivity of graphite materials allows heat to be quickly transferred to the heat conducting plate, and then the heat is quickly dissipated to the external environment through the microporous structure, thereby achieving a heat exchange effect.

[0255] In some embodiments, as Figure 7 As shown, the thermal conductivity k of the heat conducting member 84 satisfies k≥500 W / (m·K).

[0256] In these embodiments, when the thermal conductivity k of the heat conducting member 84 satisfies the above conditions, the heat conducting member 84 has sufficient thermal conductivity to conduct heat from the electrode body 52. ​​Optionally, the thermal conductivity k of the heat conducting member 84 satisfies 500 W / (m·K) ≤ k ≤ 1600 W / (m·K). For example, the thermal conductivity k of the heat conducting member 84 is 500 W / (m·K), 550 W / (m·K), 1050 W / (m·K), 1550 W / (m·K), 1600 W / (m·K), etc.

[0257] Optionally, the thermal conductivity k of the heat conducting member 84 satisfies k≥1000 W / (m·K).

[0258] Optionally, the density of the heat conducting member 84 is 2.1±0.05 g / cm 3 , insulation resistance greater than 1GΩ, voltage resistance 5400V, bending resistance > 10000 times.

[0259] In a second aspect, an embodiment of the present application provides a battery device comprising a battery cell according to any one of the embodiments of the first aspect.

[0260] In a third aspect, an embodiment of the present application provides an electrical device, comprising the battery device of the embodiment of the second aspect described above.

[0261] In some embodiments, as Figures 1 to 23 As shown, the battery cell 3 includes a housing 4, an electrode assembly 5 and a heat-conducting assembly 8. The electrode assembly 5 is located in the housing 4 and is of a wound or laminated type. The electrode assembly 5 includes an electrode body 52 and a tab 51. The electrode body 52 includes a first end face 521 and a second end face 522 that are opposite to each other in a first direction X, and a side face 523 connected between the first end face 521 and the second end face 522. The side face 523 includes two first side faces 5231 and two second side faces 5232. The two first side faces 5231 are opposite to each other in a second direction Y, and the two second side faces 523 are opposite to each other in a third direction Z. The first direction X, the second direction Y and the third direction Z are perpendicular to each other. The area of ​​the first side face 5231 is larger than the area of ​​the second side face 523.

[0262] The heat conducting assembly 8 includes an insulating member 85 and a heat conducting member 84. The insulating member 85 forms a receiving cavity 851 in at least a portion of its area. The heat conducting member 84 is disposed in the receiving cavity 851. The heat conducting member 84 includes a first heat conducting plate 841 and a second heat conducting plate 842. The tab 51 extends from the first end surface 521. The insulating member 85 includes a first insulating portion 852, a second insulating portion 853 and a middle insulating portion 854. The first insulating portion 852 includes a main body portion 8521 and a bent portion 8522 connected to each other. The main body portion 8521 and the bent portion 8522 are connected. The main bodies 8521 of the two first insulating portions 852 are respectively disposed on the two first side surfaces 5231. The two bent portions 8522 are respectively disposed on the two second side surfaces 5232. The first heat conducting plate 841 includes a middle portion. The heat conducting sheet 8411, the end heat conducting sheet 8412 and the side heat conducting sheet 8413, the second insulating portion 853 is arranged between the second end face 522 of the electrode body 52 and the shell 4, the second insulating portion 853 is insulated from the shell 4 and the second end face 522 of the electrode assembly 5, the main body 8521 of the two first insulating portions 852 is respectively connected to the two sides of the second insulating portion 853, the second heat conducting sheet 842 is arranged on the second insulating portion 853, the electrode assembly 5 is provided with a plurality of, and the plurality of electrode assemblies 5 are stacked along the second direction Y, the middle insulating portion 854 is arranged between adjacent electrode bodies 52, the middle insulating portion 854 and the second insulating portion 853 are connected to each other, the middle heat conducting sheet 8411 is arranged on the middle insulating portion 854, and the end heat conducting sheet 8412 is provided on the The main body 8521 is placed, the side heat conducting sheet 8413 is arranged on the bending portion 8522, the first heat conducting sheet 841 and the second heat conducting sheet 842 are connected to each other, and the main body 8521 is connected to a bending portion 8522 on both sides of the third direction Z. The two bending portions 8522 of the two first insulating portions 852 and located on the same side of the electrode assembly 5 extend toward each other in the second direction Y and at least partially overlap. At least one main body 8521 extends from the first end face 521 in the first direction X and is connected to the top cover assembly 6. The dimension L3 of the main body 8521 extending from the first end face 521 in the first direction X is ≥2mm. The positive projection of the heat conducting member 84 in the thickness direction of the heat conducting assembly 8 is ≥2mm to the edge of the positive projection of the insulating member 85 in the thickness direction of the heat conducting assembly 8. The minimum distance is greater than or equal to 2 mm, the thickness D3 of the heat conductor 84 satisfies 40 μm ≤ D3 ≤ 180 μm, the insulating member 85 includes two sub-insulating layers 855, the two sub-insulating layers 855 are stacked and connected to each other to form a receiving cavity 851, the thickness D1 of the sub-insulating layer 855 satisfies 5 μm ≤ D1 ≤ 100 μm, the insulating member 85 includes polyethylene or polypropylene or polyimide or polyester resin, a first through hole 815 is penetrated on the first insulating portion 852, and a second through hole 821 is penetrated on the second insulating portion 853, and the second through hole 821 and the first through hole 815 are both spaced apart from the receiving cavity 851. The heat conductor 84 includes graphite or graphene or carbon nanotubes, and the thermal conductivity k of the heat conductor 84 satisfies,k>500W / (m·K), the thermal conductivity of the heat-conducting member 84 is greater than the thermal conductivity of the insulating member 85 and the housing 4.

[0263] In these embodiments, the battery cell 3 includes a shell 4, an electrode assembly 5 and a heat-conducting assembly 8. The electrode assembly 5 is located inside the shell 4. The shell 4 provides accommodation and protection for the electrode assembly 5. The electrode assembly 5 includes an electrode body 52 and a pole ear 51. The electrode body 52 includes a first end face 521 and a second end face 522 arranged opposite to each other in a first direction X, and a side face 523 connected between the first end face 521 and the second end face 522. The electrode body 52 forms a loop with an external component through the pole ear 51 extending from the first end face 521 and / or the second end face 522. The heat-conducting assembly 8 includes an insulating member 85 and a heat-conducting member 84. The insulating member 85 at least covers the side face 523. The insulating member 85 is insulated from the shell 4 and at least part of the electrode assembly 5. The insulating member 85 can replace at least part of the Mylar film to reduce the preparation cost of the battery cell 3, reduce the thickness of the battery cell 3, and improve the energy density of the battery cell 3. The insulating member 85 at least partially An accommodating cavity 851 is formed in different regions, and a heat conducting member 84 is arranged in the accommodating cavity 851. The heat conducting member 84 and the electrode body 52 can be insulated by the insulating member 85, and the heat conducting member 84 and the electrolyte can be isolated by the insulating member 85 to improve the incompatibility problem between the heat conducting member 84 and the electrolyte. The thermal conductivity of the heat conducting member 84 is greater than the thermal conductivity of the insulating member 85 and the thermal conductivity of the shell 4. The heat conducting member 84 includes a first heat conducting plate 841. The first heat conducting plate 841 is arranged on at least part of the side surface 523 and is thermally connected to the side surface 523. The first heat conducting plate 841 is used to reduce the thermal resistance of the electrode body 52 at its side surface 523, improve the temperature uniformity of the electrode body 52 at its side surface 523, and improve the rate of heat exchange between the electrode body 52 and the external environment at its side surface 523, so as to balance the internal temperature of the battery cell 3 and improve the problem that the performance and service life of the battery cell 3 are adversely affected by the internal temperature of the battery cell 3 being too high or too low.

[0264] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: case; an electrode assembly located within the housing, the electrode assembly comprising an electrode body and a tab, the electrode body comprising a first end face and a second end face disposed opposite each other in a first direction, and a side face connected between the first end face and the second end face, the tab being connected to the electrode body and extending beyond at least one of the first end face and the second end face; A heat-conducting component includes an insulating member and a heat-conducting member, wherein at least a portion of the insulating member forms a receiving cavity, the heat-conducting member is arranged in the receiving cavity, the insulating member at least covers the side surface, the heat-conducting member includes a first heat-conducting plate, the first heat-conducting plate is arranged on at least a portion of the side surface and is thermally connected to the side surface, and the thermal conductivity of the heat-conducting member is greater than the thermal conductivity of the insulating member and the shell.

2. The battery cell according to claim 1, wherein: The electrode tab extends from the first end surface, and the insulating member covers the second end surface and the side surface of the electrode body.

3. The battery cell according to claim 2, characterized in that: The side surfaces include two first side surfaces and two second side surfaces, the two first side surfaces are arranged opposite to each other in the second direction, the two second side surfaces are arranged opposite to each other in the third direction, the first direction, the second direction and the third direction intersect each other, and the area of ​​the first side surface is greater than the area of ​​the second side surface. The insulating member includes two first insulating parts, each of which includes a main body and a bent part that are connected to each other. The main body and the bent part are connected, and the main bodies of the two first insulating parts are respectively arranged on the two first side surfaces, and the two bent parts are respectively arranged on the two second side surfaces. The first heat conductive sheet is arranged on at least one of the main body and the bent part.

4. The battery cell according to claim 3, characterized in that A first through hole is formed through the first insulating portion, and the first through hole and the accommodating cavity are spaced apart.

5. The battery cell according to claim 3, characterized in that: A first avoidance hole is provided through the first heat conducting plate, the first insulating portion covers the inner wall of the first avoidance hole, a first through hole is provided through the first insulating portion, and the first through hole is located in the first avoidance hole.

6. The battery cell according to any one of claims 3 to 5, characterized in that: The insulating member further includes a second insulating portion, which is disposed between the second end surface of the electrode body and the shell, and the main bodies of the two first insulating portions are respectively connected to two sides of the second insulating portion.

7. The battery cell according to claim 6, characterized in that The heat conducting member further includes a second heat conducting sheet, and the second heat conducting sheet is arranged on the second insulating portion.

8. The battery cell according to claim 7, characterized in that A second through hole is formed through the second insulating portion, and the second through hole and the accommodating cavity are spaced apart.

9. The battery cell according to claim 8, characterized in that A second avoidance hole is provided through the second heat conducting plate, the second insulating portion covers the inner wall of the second avoidance hole, a second through hole is provided through the second insulating portion, and the second through hole is located in the second avoidance hole.

10. The battery cell according to any one of claims 7 to 9, characterized in that: The first heat conducting plate and the second heat conducting plate are connected to each other.

11. The battery cell according to any one of claims 6 to 10, characterized in that: There are multiple electrode assemblies, and the multiple electrode assemblies are stacked along the second direction. The insulating member also includes a middle insulating portion, which is arranged between the electrode bodies of adjacent electrode assemblies. The middle insulating portion and the second insulating portion are connected to each other. The first thermal conductive plate includes an intermediate thermal conductive plate, which is arranged in the middle insulating portion.

12. The battery cell according to any one of claims 3 to 11, characterized in that: The main body is connected to a bending portion on both sides of the third direction respectively, and the two bending portions of the two first insulating portions and located on the same side of the electrode assembly extend toward each other in the second direction.

13. The battery cell according to claim 12, characterized in that: The two bending portions extend toward each other in the second direction, and the two bending portions at least partially overlap in the third direction.

14. The battery cell according to any one of claims 3 to 13, characterized in that: The shell includes an opening in the first direction, and the battery cell also includes a top cover assembly, which covers the opening and is connected to the tab. At least one of the main bodies extends from the first end surface in the first direction and is connected to the top cover assembly.

15. The battery cell according to claim 14, characterized in that A dimension L3 of the main body extending out of the first end surface in the first direction is ≥2 mm.

16. The battery cell according to any one of claims 1 to 15, characterized in that: The minimum distance between the orthographic projection of the heat-conducting member in the thickness direction of the heat-conducting component and the edge of the orthographic projection of the insulating member in the thickness direction of the heat-conducting component is greater than or equal to 2 mm.

17. The battery cell according to any one of claims 1 to 16, characterized in that: The thickness D3 of the heat conducting member satisfies 40 μm≤D3≤180 μm.

18. The battery cell according to any one of claims 1 to 17, characterized in that: The insulating member includes two sub-insulating layers, which are stacked and connected to each other to form the accommodation cavity. The thickness D1 of the sub-insulating layer satisfies 5 μm≤D1≤100 μm.

19. The battery cell according to any one of claims 1 to 18, characterized in that: The insulating member comprises polyethylene, polypropylene, polyimide or polyester resin.

20. The battery cell according to any one of claims 1 to 19, characterized in that: The heat conducting member includes graphite, graphene or carbon nanotubes.

21. The battery cell according to any one of claims 1 to 20, characterized in that: The thermal conductivity k of the heat conducting member satisfies k≥500 W / (m·K).

22. A battery device, characterized in that: A battery cell comprising any one of claims 1 to 21.

23. An electrical device, characterized in that: A battery device comprising the battery device described in claim 22.

Images