Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device. The 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 a first heat conduction part, the first heat conduction part is in heat conduction connection with the side face, the heat conductivity of the heat conduction assembly is larger than that of the shell, the heat conduction assembly and the electrode assembly are mutually insulated, the shell comprises an opening in the first direction, the battery monomer further comprises a top cover assembly, the top cover assembly covers the opening, and the top cover assembly is provided with an electrode terminal; the heat conduction assembly further comprises a second heat conduction part, the second heat conduction part is in heat conduction connection with the tab, and the second heat conduction part is in heat conduction connection with the first heat conduction part.

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 of the battery cell tabs 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 comprising an electrode body and a tab, the electrode body comprising a first end face and a second end face arranged opposite to 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 assembly, comprising a first heat-conducting portion, the first heat-conducting portion and the side face being heat-conductively connected, the heat-conducting assembly having a thermal conductivity greater than that of the shell, and the heat-conducting assembly and the electrode assembly being insulated from each other, wherein the shell comprises an opening in the first direction, the battery cell further comprises a top cover assembly, the top cover assembly covers the opening, the top cover assembly has an electrode terminal, the electrode terminal is connected to the tab, the heat-conducting assembly further comprises a second heat-conducting portion, the second heat-conducting portion is heat-conductively connected to the tab, and the second heat-conductive portion is heat-conductively connected to the first heat-conducting portion.

[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 an external component through the pole ear extending from the first end face and / or the second end face. The thermal conductivity of the heat-conducting assembly is greater than the thermal conductivity of the shell. The heat-conducting assembly includes a first heat-conducting portion. The first heat-conducting portion is connected to the side of the electrode body by heat conduction, which can reduce the thermal resistance of the electrode body at its side, thereby improving the electrode The temperature uniformity of the main body at its side, and the rate of heat exchange between the electrode main body at its side and the external environment is improved 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. The top cover assembly covers the opening of the shell, and the electrode terminal of the tab and the top cover assembly are connected to achieve electrical connection. The heat-conducting assembly also includes a second heat-conducting part that is heat-conductingly connected to the tab, and the second heat-conducting part is heat-conductingly connected to the first heat-conducting part, so that the heat-conducting assembly can increase the heat conduction rate at the tab to balance the temperature at the tab and the electrode main body, and improve the problem that the performance of the battery cell is affected by the high temperature at the tab.

[0007] In some embodiments, the battery cell further includes a switching mechanism connected between the tab and the electrode terminal, and the second heat conducting portion is further heat-conductingly connected to the switching mechanism.

[0008] In the technical solution of the embodiment of the present application, the battery cell also includes a transfer mechanism, which is connected between the tab and the electrode terminal. The second heat-conducting part is also heat-conductingly connected to the transfer mechanism, so that the heat-conducting component can transfer the heat conduction rate at the transfer mechanism to balance the temperature at the transfer mechanism, thereby improving the problem of affecting the performance of the battery cell due to excessively high temperature at the transfer mechanism.

[0009] In some embodiments, the electrode tab includes a folded section and an extended section, the folded section is connected to the electrode body, one side of the extended section is connected to the folded section, and the other side is connected to the transfer mechanism, the second heat conducting portion is connected to the side of the extended section facing the folded section, or the second heat conducting portion is connected to the side of the extended section facing the transfer mechanism.

[0010] In the technical solution of the embodiment of the present application, the second heat-conducting part is connected to the side of the extension section facing the convergence section, or the second heat-conducting part is connected to the side of the extension section facing the adapter mechanism. The second heat-conducting part is used to improve the heat conduction rate at the pole ear, thereby improving the problem that the temperature at the pole ear is too high, thereby heating the pole piece, causing the electrode body to heat up, and the performance of the battery cell to decrease.

[0011] In some embodiments, the extension section includes a first sub-segment, a second sub-segment, and a third sub-segment connecting the first sub-segment and the second sub-segment, which are spaced apart along the first direction. The first sub-segment is connected to the gathering section, the second sub-segment is connected to the transfer mechanism, and the second heat-conducting portion is connected to the side of the first sub-segment facing the gathering section.

[0012] In the technical solution of the embodiment of the present application, the extension section includes a first sub-segment, a second sub-segment and a third sub-segment connecting the first sub-segment and the second sub-segment, which are arranged at intervals along the first direction. The second sub-segment is connected to the adapter mechanism to increase the contact area between the adapter mechanism and the pole ear. The second heat-conducting part is connected to the side of the first sub-segment toward the convergence section to reduce the difficulty of connecting the second heat-conducting part and the pole ear.

[0013] In some embodiments, 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, the area of ​​the first side surface is greater than the area of ​​the second side surface, two pole ears are provided, the two pole ears extend from the first end surface and are arranged at intervals along the third direction, two first heat conducting parts and two second heat conducting parts are respectively provided, the two first heat conducting parts are respectively arranged on the two second side surfaces, the two second heat conducting parts are respectively connected to one end of the two first heat conducting parts facing the pole ears, and the two second heat conducting parts are respectively connected to the extension sections of the two pole ears.

[0014] In the technical solution of the embodiment of the present application, the two pole ears extend out from the first end face and are arranged at intervals along the third direction. The two first heat conducting parts are respectively arranged on the two second side faces. The thickness of the battery cell will not be increased due to the arrangement of the heat conducting component. Since the expansion of the electrode assembly mainly occurs at the first side face, when the first heat conducting part is arranged at the second side face, the interference of the first heat conducting part on the expansion of the electrode assembly can be reduced. The two second heat conducting parts are respectively connected to one end of the two first heat conducting parts facing the pole ears, and the two second heat conducting parts are respectively connected to the extension sections of the two pole ears. Each pole ear is connected to a second heat conducting part so that the heat at the electrode body and each pole ear can be transferred to the first heat conducting part through the second heat conducting part, so as to improve the heat conduction rate at the pole ear and improve the problem that the temperature at the pole ear is too high, thereby heating the pole piece, causing the electrode body to heat up and the battery cell performance to decrease.

[0015] In some embodiments, 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 with each other, the area of ​​the first side surfaces is greater than the area of ​​the second side surfaces, two first heat conducting parts and two second heat conducting parts are respectively provided, the two first heat conducting parts are respectively provided on the two first side surfaces, each second heat conducting part is respectively connected to a first heat conducting part, and the two second heat conducting parts are respectively connected to different positions of the extension section of the same pole ear.

[0016] In the technical solution of the embodiment of the present application, each second heat-conducting part is respectively connected to a first heat-conducting part, and the two second heat-conducting parts are respectively connected to different positions of the extension section of the same pole ear, so as to better improve the heat conduction rate at the pole ear and improve the problem of affecting the performance of the battery cell due to excessive temperature at the pole ear.

[0017] In some embodiments, the extension section includes a first sub-segment, a second sub-segment, and a third sub-segment connecting the first sub-segment and the second sub-segment, which are spaced apart along the first direction. The first sub-segment is connected to the retracting section, and the second sub-segment is connected to the transfer mechanism. One of the two second heat-conducting parts is connected to the first sub-segment, and the other is connected to the second sub-segment.

[0018] In the technical solution of the embodiment of the present application, one of the two second heat-conducting parts is connected to the first sub-segment, and the other is connected to the second sub-segment. The connection areas of the two second heat-conducting parts and the tabs are reasonably allocated to improve the connection reliability between the second heat-conducting parts and the tabs.

[0019] 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, and the transfer mechanism includes a first connecting segment and a second connecting segment arranged along the third direction, the tab is connected to the first connecting segment, and the second heat conducting portion is connected to the second connecting segment.

[0020] In the technical solution of the embodiment of the present application, the adapter mechanism includes a first connecting section and a second connecting section, the pole ear and the first connecting section are connected, and the second heat conducting part is connected to the second connecting section. The second heat conducting part is used to improve the heat conduction rate at the adapter mechanism, thereby improving the problem that the temperature at the adapter mechanism is too high, thereby heating the pole piece and causing the performance of the battery cell to be reduced.

[0021] In some embodiments, two first heat conducting parts and two second heat conducting parts are respectively provided, the two first heat conducting parts are respectively provided on the two first side surfaces, each second heat conducting part is respectively connected to one first heat conducting part, and the two second heat conducting parts are respectively connected to different positions of the second connecting section of the same adapter mechanism.

[0022] In the technical solution of the embodiment of the present application, two first heat-conducting parts are respectively arranged on the two first side surfaces, each second heat-conducting part is respectively connected to a first heat-conducting part, and the two second heat-conducting parts are respectively connected to different positions of the second connecting section of the same adapter mechanism, so as to better improve the heat conduction rate at the adapter mechanism and improve the problem of affecting the performance of the battery cell due to excessive temperature at the adapter mechanism.

[0023] In some embodiments, two electrode assemblies are provided, and the two electrode assemblies are stacked along the second direction. The adapter mechanism is provided with two first connecting sections, and the two first connecting sections are respectively provided on both sides of the second connecting section in the second direction. The pole ears of the two electrode assemblies are respectively connected to the two first connecting sections. There are two first heat conducting parts and two second heat conducting parts respectively, and the two first heat conducting parts are provided on two first side surfaces of the same electrode body. The two second heat conducting parts are respectively connected to one end of the two first heat conducting parts facing the adapter mechanism, and the two second heat conducting parts are respectively connected to the second connecting section and the pole ears of the adapter mechanism.

[0024] In the technical solution of the embodiment of the present application, two first heat-conducting parts are arranged on both sides of an electrode body in the second direction, and the two second heat-conducting parts are respectively connected to one end of the two first heat-conducting parts facing the adapter mechanism, and the two second heat-conducting parts are respectively connected to the second connecting section and the pole ear of the adapter mechanism to reduce the difficulty of connecting the second heat-conducting parts and the pole ear and the adapter mechanism; and the two second heat-conducting parts are respectively connected to the pole ear and the adapter mechanism to better stabilize the temperature at the pole ear.

[0025] In some embodiments, the tab extends from the first end surface, and the heat conducting assembly further includes a third heat conducting portion, which is disposed along the first direction between the shell and at least a portion of the second end surface, and is connected to the first heat conducting portion.

[0026] In the technical solution of the embodiment of the present application, the heat-conducting component also includes a third heat-conducting portion arranged along the first direction between the shell and at least part of the second end face. The third heat-conducting portion is connected to the first heat-conducting portion to increase the contact area between the heat-conducting component and the shell, so as to increase the heat conduction rate of the heat-conducting component to the pole ear, thereby improving the problem of affecting the performance of the battery cell due to excessively high temperature at the pole ear.

[0027] In some embodiments, the tab extends from the first end face, and the battery cell further includes a first insulating film, which covers the side face and the second end face of the electrode body; wherein the first heat conducting portion is located between the first insulating film and the electrode assembly, or the first heat conducting portion is located between the first insulating film and the shell.

[0028] In the technical solution of the embodiment of the present application, the first insulating film is covered on the side and second end face of the electrode body to insulate the shell and the electrode assembly. The first heat-conducting part is located between the first insulating film and the electrode assembly. The first insulating film plays a role in supporting and protecting the first heat-conducting part, reducing the problem of damage to the first heat-conducting part under external force impact, or the first heat-conducting part is located between the first insulating film and the shell to improve the insulation reliability between the first heat-conducting part and the electrode assembly, and improve the heat conduction efficiency between the first heat-conducting part and the shell.

[0029] In some embodiments, the heat-conducting component includes an insulating member and a heat-conducting member, and at least a partial area of ​​the insulating member forms a receiving cavity, and the heat-conducting member is arranged in the receiving cavity. The heat-conducting member includes a first heat-conducting plate and a second heat-conducting plate. The first heat-conducting part is composed of the first heat-conducting plate and the insulating member, and the second heat-conducting part is composed of the second heat-conducting plate and the insulating member. The first heat-conducting plate and the second heat-conducting plate are connected.

[0030] In the technical solution of the embodiment of the present application, the heat-conducting component includes an insulating part and a heat-conducting part. At least a partial area of ​​the insulating part forms an accommodating cavity. The heat-conducting part is arranged in the accommodating cavity. The heat-conducting part is used to improve the heat-conducting capacity of the heat-conducting component. The heat-conducting part includes a first heat-conducting sheet and a second heat-conducting sheet. The first heat-conducting sheet and the insulating part form a first heat-conducting part, and the second heat-conducting sheet and the insulating part form a second heat-conducting part. The first heat-conducting sheet and the second heat-conducting sheet are connected. In this way, when the first heat-conducting sheet and the second heat-conducting sheet are combined to conduct heat, the first heat-conducting sheet and the second heat-conducting sheet are insulated from the electrode assembly by the insulating part, and the insulating part can isolate the heat-conducting sheet and the electrolyte to improve the problem of incompatibility between the heat-conducting sheet and the electrolyte, which affects the performance of the battery cell.

[0031] In some embodiments, the thermal conductor includes graphite or graphene or carbon nanotubes.

[0032] 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 member is improved by using the graphite, graphene or carbon nanotube thermal conductive materials.

[0033] In some embodiments, the thermal conductivity k of the heat conducting member satisfies k>500 W / (m·K).

[0034] 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 member has sufficient thermal conductivity to conduct the heat of the electrode body.

[0035] 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.

[0036] 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

[0037] 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:

[0038] Figure 1 is a structural schematic diagram of a vehicle provided in one embodiment of the present application;

[0039] Figure 2 is a structural diagram of a battery device provided in one embodiment of the present application;

[0040] Figure 3 This is a schematic structural diagram of a battery module provided in one embodiment of the application;

[0041] Figure 4 is an exploded view of a battery cell provided in one embodiment of the present application;

[0042] Figure 5 This is a schematic structural diagram of an electrode assembly of a battery cell provided in one embodiment of the present application;

[0043] Figure 6 is an exploded view of a battery cell provided in another embodiment of the present application;

[0044] Figure 7 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0045] Figure 8 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0046] Figure 9 is an exploded view of a battery cell provided in another embodiment of the present application;

[0047] Figure 10 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0048] Figure 11 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0049] Figure 12 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0050] Figure 13 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0051] Figure 14 yes Figure 13 Schematic diagram of the enlarged structure at B in the middle;

[0052] Figure 15 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0053] Figure 16 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0054] Figure 17 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0055] Figure 18 This is a partial structural diagram of a battery cell provided in one embodiment of the present application;

[0056] Figure 19 is an exploded view of a battery cell provided in another embodiment of the present application;

[0057] Figure 20 yes Figure 6 Cross-section at AA in the middle.

[0058] Reference numerals:

[0059] 1. Vehicle; 101. Motor; 102. Controller; 2. Battery device; 201. Battery module; 202. Case; 2021. First case; 2022. Second case;

[0060] 3. Battery cells;

[0061] 4. Shell; 41. Opening;

[0062] 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; 511. Retracted section; 512. Extended section; 5121. First subsegment; 5122. Second subsegment; 5123. Third subsegment;

[0063] 6. Top cover assembly; 61. Electrode terminal;

[0064] 7. Transfer agency;

[0065] 71. First connecting section; 72. Second connecting section;

[0066] 8. Heat-conducting assembly; 81. First heat-conducting portion; 83. Second heat-conducting portion; 82. Third heat-conducting portion; 84. Heat-conducting element; 841. First heat-conducting sheet; 842. Second heat-conducting sheet; 85. Insulating element; 851. Accommodating cavity;

[0067] 91. a first insulating film;

[0068] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] The reason for the above problem is that when the battery cell is in working state, the current is output from the pole ear through the electrode terminal of the top cover assembly to the outside world. The current passing through the pole ear causes the temperature to rise. The high temperature will be transmitted from the pole ear to the electrode body, causing the temperature of the electrode body to rise, so that the battery cell reaches the current limiting temperature prematurely, resulting in a decrease in the performance and service life of the battery cell.

[0078] 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 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 an external component through the pole ear extending from the first end face and / or the second end face. The thermal conductivity of the heat-conducting assembly is greater than the thermal conductivity of the shell. The heat-conducting assembly includes a first heat-conducting portion, which is connected to the side surface of the electrode body by heat conduction, so as to reduce the heat of the electrode body at its side surface. Resistance, improve the temperature uniformity of the electrode body at its side, and improve the rate of heat exchange between the electrode body and the external environment at its side, 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. The top cover assembly covers the opening of the shell, and the electrode terminal of the tab and the top cover assembly are connected to achieve electrical connection. The heat-conducting assembly also includes a second heat-conducting part that is thermally connected to the tab, and the second heat-conducting part is thermally connected to the first heat-conducting part, so that the heat-conducting assembly can improve the heat conduction rate at the tab, so as to balance the temperature at the tab and the electrode body, and improve the problem that the performance of the battery cell is affected by the high temperature at the tab.

[0079] The technical solutions described in the embodiments of the present application are applicable to battery devices and electrical devices using battery devices.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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).

[0085] 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.

[0086] 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.

[0087] 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 .

[0088] Figure 2 A schematic structural diagram of a battery device according to an embodiment of the present application is shown.

[0089] 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.

[0090] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells 3 .

[0091] 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.

[0092] 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 .

[0093] As an example, the battery cell assembly may be a battery module 201 , and the battery cell assembly may be accommodated in the box by fixing the battery module 201 in the box.

[0094] 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 .

[0095] 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.

[0096] 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.

[0097] 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.

[0098] Figure 3 A schematic structural diagram of a battery module 201 according to an embodiment of the present application is shown.

[0099] 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.

[0100] 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 .

[0101] 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 makes up a battery. Figure 4 The battery cell 3 includes a top cover assembly 6, a shell 4 and an electrode assembly 5.

[0102] 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.

[0103] The electrode assembly 5 may be a wound structure, a laminated structure, or a mixed structure of wound and laminated structures.

[0104] 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.

[0105] 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.

[0106] In some embodiments, the shape of the electrode assembly 5 can be cylindrical, flat, or polygonal.

[0107] 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.

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] See also Figures 5 to 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 is an exploded view of a battery cell provided in another embodiment of the present application; Figure 7 This is a partial structural diagram of a battery cell provided in one embodiment of the present application; Figure 8 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0113] 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. 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 oppositely arranged 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 from at least one of the first end face 521 and the second end face 522. The heat-conducting assembly 8 includes a first end face 521 and a second end face 522. The heat-conducting part 81, the first heat-conducting part 81 and the side 523 are thermally connected, the thermal conductivity of the heat-conducting component 8 is greater than the thermal conductivity of the shell 4, the heat-conducting component 8 and the electrode assembly 5 are insulated from each other, wherein the shell 4 includes an opening 41 in the first direction X, the battery cell 3 also includes a top cover assembly 6, the top cover assembly 6 covers the opening 41, the top cover assembly 6 has an electrode terminal, the electrode terminal 61 is connected to the pole ear 51, the heat-conducting component 8 also includes a second heat-conducting part 83, the second heat-conducting part 83 is thermally connected to the pole ear 51, and the second heat-conducting part 83 is thermally connected to the first heat-conducting part 81.

[0114] 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 thermal conductivity of the heat-conducting assembly 8 is greater than the thermal conductivity of the shell 4. The heat-conducting assembly 8 includes a first heat-conducting portion 81. The first heat-conducting portion 81 connected to the side face 523 of the electrode body 52 by heat conduction can reduce the electrode body 52 on its side. The thermal resistance at 523 is improved, the temperature uniformity of the electrode body 52 at its side 523 is improved, and the rate of heat exchange between the electrode body 52 and the external environment at its side 523 is improved 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. The top cover assembly 6 covers the opening 41 of the shell 4, and the pole ear 51 and the electrode terminal 61 of the top cover assembly 6 are connected to achieve electrical connection. The heat-conducting assembly 8 also includes a second heat-conducting part 83 that is heat-conductingly connected to the pole ear 51. The second heat-conducting part 83 is heat-conductingly connected to the first heat-conducting part 81, so that the heat-conducting assembly 8 can increase the heat conduction rate at the pole ear 51 to balance the temperature at the pole ear 51, and improve the problem that the performance of the battery cell 3 is affected by the excessively high temperature at the pole ear 51.

[0115] The electrode body 52 is formed by winding or stacking a separator, a positive electrode sheet, and a negative electrode sheet. The tabs 51 include a positive tab and a negative tab. Both the positive tab and the negative tab extend from the first end face 521 or the second end face 522, or one of the positive tab and the negative tab extends from the first end face 521 and the other extends from the second end face 522.

[0116] 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 side openings 41 in the first direction X, the two top cover assemblies 6 respectively cover the 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.

[0117] Exemplarily, the first direction X is the height direction of the electrode assembly 5 .

[0118] The first heat-conducting portion 81 is thermally connected to the side surface 523 of the electrode body 52, and the first heat-conducting portion 81 is directly attached to or abuts the side surface 523 of the electrode body 52; or the first heat-conducting portion 81 is a plating layer arranged on the side surface 523; or the first heat-conducting portion 81 and the side surface 523 of the electrode body 52 are spaced apart, and the first heat-conducting portion 81 is indirectly connected to the side surface 523 through a heat-conducting medium, and the heat-conducting medium can be air, metal, or heat-conducting glue, etc.

[0119] The second heat-conducting part 83 is thermally connected to the first heat-conducting part 81. Specifically, the heat-conducting component 8 includes an insulating part (not shown in the figure) and a heat-conducting part (not shown in the figure). At least a part of the insulating part forms an accommodating cavity, and the heat-conducting part is arranged in the accommodating cavity. Then the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the second heat-conducting part 83 can be directly connected. Exemplarily, the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the second heat-conducting part 83 are integrally formed or bonded to each other or abutted against each other; or the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the second heat-conducting part 83 are indirectly connected through a heat-conducting medium, and the heat-conducting medium can be a metal material part or a heat-conducting glue, etc.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] The first heat conducting portion 81 may be in a strip shape, a flat plate shape, a mesh plate shape, etc. The first heat conducting portion 81 may be in a rectangular shape, a circular shape, a diamond shape, etc. The specific shape and size of the first heat conducting portion 81 may be flexibly designed.

[0124] Optionally, multiple first heat conducting parts 81 are spaced apart on the side surface 523 of the electrode body 52 , which can conduct heat of the electrode body 52 through the first heat conducting parts 81 , reduce the size of the heat conducting component 8 , and reduce the production cost of the battery cell 3 .

[0125] During the operation of the electrode assembly 5, the temperature of the end of the electrode body 52 close to the electrode ear 51 is relatively higher, and the temperature of the end away from the electrode ear 51 is relatively lower. The first heat conduction part 81 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.

[0126] Optionally, in the first direction X, the first heat conducting portion 81 extends to both ends of the electrode body 52 .

[0127] Optionally, the first heat conducting portion 81 covers the entire side surface 523 of the electrode body 52 to improve the heat conduction rate of the first heat conducting portion 81 .

[0128] The thermal conductivity of the heat-conducting component 8 is greater than that of the shell 4 . The heat-conducting component 8 may include graphite, graphene, carbon nanotubes, or the like.

[0129] When the battery cell 3 is in working state, the current is output from the pole ear 51 to the outside through the electrode terminal 61. The current passing through the pole ear 51 causes the temperature to rise. The high temperature will be transmitted from the pole ear 51 to the electrode body 52, causing the temperature of the electrode body 52 to rise. The battery cell 3 reaches the current limiting temperature prematurely, resulting in a decrease in the performance of the battery cell 3.

[0130] Therefore, the tab 51 and the second heat conducting portion 83 are thermally connected so that the heat at the tab 51 can be transferred to the outside through the first heat conducting portion 81 and the second heat conducting portion 83, thereby improving the problem of the tab 51 heating the electrode body 52. ​​Alternatively, in a low temperature environment, the first heat conducting portion 81 and the second heat conducting portion 83 can also be used to increase the temperature of the tab 51.

[0131] Optional, such as Figure 7 As shown, the second heat conducting portion 83 is connected between the first heat conducting portion 81 and the tab 51, and the first heat conducting portion 81 extends to the first side surface 5231 of the electrode body 52. ​​Then, the first heat conducting portion 81 can be used to conduct heat from the first side surface 523 of the electrode body 52 and the tab 51 at the same time; or, as shown Figure 6 As shown, the first heat-conducting portion 81 extends to the second side surface 5232, which helps to reduce the size of the heat-conducting component 8 in the second direction Y, and since the expansion of the electrode assembly 5 mainly occurs at the first side surface 5231, when the first heat-conducting portion 81 is arranged at the second side surface 5232, the interference of the first heat-conducting portion 81 on the expansion of the electrode assembly 5 can be reduced.

[0132] Optionally, the second heat conducting portion 83 may be connected to one first heat conducting portion 81 ; or the second heat conducting portion 83 may be connected to two or more first heat conducting portions 81 that are spaced apart.

[0133] Optionally, the electrode body 52 includes a positive electrode ear and a negative electrode ear, and the positive electrode ear and the negative electrode ear are connected to different second heat-conducting parts 83, thereby reducing the size of a single second heat-conducting part 83 and reducing the risk of interference between the second heat-conducting part 83 and other components of the battery cell 3; or the positive electrode ear and the negative electrode ear are connected to the same second heat-conducting part 83 to increase the connection area between the second heat-conducting part 83 and the first heat-conducting part 81, thereby improving the thermal conductivity efficiency of the heat-conducting component 8.

[0134] Optionally, the second heat conducting portion 83 and the tab 51 may be connected by abutment, welding, bonding, etc., or the second heat conducting portion 83 and the tab 51 may be connected by a heat transfer medium.

[0135] Optionally, the first heat conducting portion 81 and the second heat conducting portion 83 are integrally formed to enhance the heat conducting efficiency of the heat conducting assembly 8 .

[0136] Optionally, the positive and negative electrode ears extend from the first end face 521 and the second end face 522 respectively, and the two second heat-conducting parts 83 are respectively connected to the positive electrode ear and the negative electrode ear. The two second heat-conducting parts 83 can be connected to the same first heat-conducting part 81 to reduce the material cost of the heat-conducting component 8, or the two second heat-conducting parts 83 are connected to the two first heat-conducting parts 81 to improve the heat conduction rate of the heat-conducting component 8.

[0137] See also Figure 9 , Figure 9 This is an exploded view of a battery cell provided in another embodiment of the present application.

[0138] In some embodiments, as Figure 9 As shown, the battery cell 3 further includes a switching mechanism 7 , which is connected between the tab 51 and the top cover assembly 6 , and the second heat conducting portion 83 is also heat-conductingly connected to the switching mechanism 7 .

[0139] In these embodiments, the battery cell 3 also includes a transfer mechanism 7, which is connected between the tab 51 and the top cover assembly 6. The second heat conducting portion 83 is also heat-conductingly connected to the transfer mechanism 7, so that the heat conducting assembly 8 can increase the heat conduction rate at the transfer mechanism 7 to balance the temperature at the transfer mechanism 7 and improve the problem of affecting the performance of the battery cell 3 due to excessively high temperature at the transfer mechanism 7.

[0140] The second heat conducting part 83 and the adapter mechanism 7 are thermally connected, and the second heat conducting part 83 and the adapter mechanism 7 are directly connected, or the second heat conducting part 83 and the adapter mechanism 7 are indirectly connected through a heat conducting medium, and the heat conducting medium can be air, metal, or heat conducting glue, etc.

[0141] At least one of the tab 51 and the adapter mechanism 7 is thermally connected to the second heat conducting portion 83 .

[0142] The tab 51 is connected to the electrode terminal 61 through the adapter mechanism 7. The high temperature at the electrode terminal 61 can also be transmitted to the electrode body 52 through the tab 51, causing the temperature of the electrode body 52 to rise, and the battery cell 3 to reach the current limiting temperature prematurely, resulting in a decrease in the performance of the battery cell 3.

[0143] Therefore, the adapter mechanism 7 is connected to the second heat conducting portion 83 so that the heat at the adapter mechanism 7 can be transferred to the outside through the first heat conducting portion 81 and the second heat conducting portion 83, thereby improving the problem of the adapter mechanism 7 heating the electrode body 52. ​​Alternatively, in a low-temperature environment, the temperature of the adapter mechanism 7 can also be increased through the first heat conducting portion 81 and the second heat conducting portion 83.

[0144] Optionally, the tab 51 and the adapter 7 are respectively connected to a second heat conducting portion 83 to improve the heat conduction rate of the heat conducting component 8; or the tab 51 and the adapter 7 are connected to the same second heat conducting portion 83 to save the material cost of the heat conducting component 8.

[0145] Optionally, the second heat conducting part 83 and the adapter mechanism 7 may be connected by abutment, welding, bonding, etc., or the second heat conducting part 83 and the adapter mechanism 7 may be connected by a heat transfer medium.

[0146] Optionally, the electrode terminal 61 and the tab 51 are respectively connected to the two side surfaces of the adapter mechanism 7 in the first direction X, and the connection area between the second heat conducting portion 83 and the adapter mechanism 7 and the connection area between the adapter mechanism and the electrode terminal 61 and the tab 51 are spaced apart. The second heat conducting portion 83 can be arranged on either side of the adapter mechanism 7 in the first direction X, or the second heat conducting portion 83 can be arranged on the two side surfaces of the adapter mechanism 7 in the first direction X.

[0147] See also Figure 10 , Figure 10 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0148] In some embodiments, as Figure 6 、 Figure 7 and Figure 10 As shown, the electrode ear 51 includes a folding section 511 and an extension section 512, the folding section 511 is connected to the electrode body 52, one side of the extension section 512 is connected to the folding section 511, and the other side is connected to the adapter mechanism 7, the second heat conducting portion 83 is connected to the side of the extension section 512 facing the folding section 511, or the second heat conducting portion 83 is connected to the side of the extension section 512 facing the adapter mechanism 7.

[0149] In these embodiments, the second heat conducting portion 83 is connected to the side of the extension section 512 toward the retracted section 511, or the second heat conducting portion 83 is connected to the side of the extension section 512 toward the adapter mechanism 7. The second heat conducting portion 83 is used to improve the heat conduction rate at the pole tab 51, thereby improving the problem that the temperature at the pole tab 51 is too high, thereby heating the pole piece, causing the electrode body 52 to heat up, and the performance of the battery cell 3 to decrease.

[0150] Illustratively, the gathering section 511 extends along the first direction X, one end of the extension section 512 is connected to the gathering section 511, and the other end extends along the second direction Y, the adapter mechanism 7 is connected to the extension section 512, and the extension section 512 is used to increase the connection area between the tab 51 and the adapter mechanism 7, thereby improving the connection reliability between the tab 51 and the adapter mechanism 7.

[0151] like Figure 10 As shown, the adapter mechanism 7 is connected to the side of the extension section 512 close to the top cover assembly 6 in the first direction X, and the second heat-conducting portion 83 is connected to the side of the extension section 512 away from the top cover assembly 6 in the first direction X, so that the pole tab 51 and the second heat-conducting portion 83 have sufficient contact area, thereby improving the connection reliability between the second heat-conducting portion 83 and the pole tab 51, and ensuring that the pole tab 51 and the adapter mechanism 7 have sufficient contact area.

[0152] Or, as Figure 7 As shown, the extension section 512 extends in the third direction Z, the adapter mechanism 7 and the second heat-conducting part 83 are both connected to the side surface of the extension section 512 facing the top cover assembly 6, and the adapter mechanism 7 and the second heat-conducting part 83 are spaced apart in the third direction Z to reasonably match the positions of the second heat-conducting part 83, the tab 51 and the adapter mechanism 7, thereby reducing the difficulty of connecting the second heat-conducting part 83 and the tab 51.

[0153] In some embodiments, as Figure 6 and Figure 10 As shown, the extension section 512 includes a first sub-segment 5121, a second sub-segment 5122 and a third sub-segment 5123 connecting the first sub-segment 5121 and the second sub-segment 5122, which are arranged at intervals along the first direction X. The first sub-segment 5121 is connected to the gathering section 511, the second sub-segment 5122 is connected to the adapter mechanism 7, and the second heat conducting portion 83 is connected to the side of the first sub-segment 5121 facing the gathering section 511.

[0154] In these embodiments, the extension section 512 includes a first sub-segment 5121, a second sub-segment 5122, and a third sub-segment 5123 connecting the first sub-segment 5121 and the second sub-segment 5122, which are spaced apart along the first direction X. The second sub-segment 5122 is connected to the adapter mechanism 7 to increase the contact area between the adapter mechanism 7 and the tab 51. The second heat conducting portion 83 is connected to the side of the first sub-segment 5121 toward the convergence section 511 to reduce the difficulty of connecting the second heat conducting portion 83 and the tab 51.

[0155] One side of the extension section 512 is connected to the adapter mechanism 7, and the second heat conducting portion 83 is connected to the side of the extension section 512 facing the retracted section 511. Specifically, the adapter mechanism 7 is connected to the second sub-segment 5122, and the second heat conducting portion 83 is connected to the first sub-segment 5121.

[0156] Exemplarily, the tabs 51 of each pole piece are gathered in the folding section 511, and after folding, they are bent along the second direction Y to form a first sub-segment 5121, and then the tabs 51 are bent and extended along the first direction X to form a third sub-segment 5123, and then the tabs 51 are extended along the second direction Y to form a second sub-segment 5122.

[0157] Optionally, the area of ​​the second sub-segment 5122 is larger than that of the first sub-segment 5121, the second heat conducting part 83 is connected to the first sub-segment 5121, and the adapter mechanism 7 and another second heat conducting part 83 are connected to the second sub-segment 5122 to increase the contact area between the pole tab 51 and the adapter mechanism 7, and improve the connection reliability between the pole tab 51 and the adapter mechanism 7 and between the pole tab and the second heat conducting part 83.

[0158] In some embodiments, as Figure 6 and Figure 8 As 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 larger than the area of ​​the second side surface 5232, two pole ears 51 are provided, the two pole ears 51 extend from the first end surface 521, and are arranged at intervals along the third direction Z, two first heat conducting parts 81 and two second heat conducting parts 83 are respectively provided, the two first heat conducting parts 81 are respectively arranged on the two second side surfaces 5232, the two second heat conducting parts 83 are respectively connected to one end of the two first heat conducting parts 81 facing the pole ear 51, and the two second heat conducting parts 83 are respectively connected to the extension sections 512 of the two pole ears 51.

[0159] In these embodiments, the two tabs 51 extend from the first end surface 521 and are spaced apart along the third direction Z. The two first heat-conducting portions 81 are respectively arranged on the two second side surfaces 5232. The thickness of the battery cell 3 will not be increased due to the provision of the heat-conducting component 8. Moreover, since the expansion of the electrode assembly 5 mainly occurs at the first side surface 5231, when the first heat-conducting portion 81 is arranged on the second side surface 5232, the interference of the first heat-conducting portion 81 on the expansion of the electrode assembly 5 can be reduced. The two second heat-conducting portions 83 are respectively connected to one end of the two first heat-conducting portions 81 facing the tabs 51, and the two second heat-conducting portions 83 are respectively connected to the extension sections 512 of the two tabs 51. Each tab 51 is connected to a second heat-conducting portion 83, so that the heat at the electrode body 52 and each tab 51 can be transferred to the first heat-conducting portion 81 through the second heat-conducting portion 83, thereby improving the heat conduction rate at the tab 51 and improving the problem that the temperature at the tab 51 is too high, thereby heating the pole piece, causing the electrode body 52 to heat up, and reducing the performance of the battery cell 3.

[0160] Optionally, there are multiple first heat conducting parts 81, at least two first heat conducting parts 81 are arranged at intervals on the same second side 5232, and several first heat conducting parts 81 arranged on the same second side 5232 are connected to the same second heat conducting part 83. The first heat conducting parts 81 arranged at intervals can not only save the material cost of the heat conducting component 8, but also improve the problem of excessive heat concentration in a part of the second side 5232 when the first heat conducting part 81 transfers the temperature of the tab 51, and can balance the temperature at the second side 5232.

[0161] Optionally, the first heat conducting part 81 and the second heat conducting part 83 are integrally formed, and the first heat conducting part 81 and the second heat conducting part 83 are formed by bending the base material once, which reduces the processing difficulty of the first heat conducting part 81 and the second heat conducting part 83.

[0162] See also Figure 11 , Figure 11 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0163] In some embodiments, as Figure 6 and Figure 11As 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 and the third direction intersect with each other. The area of ​​the first side surface 5231 is larger than the area of ​​the second side surface 523. Two first heat-conducting parts 81 and two second heat-conducting parts 83 are respectively provided. The two first heat-conducting parts 81 are respectively arranged on the two first side surfaces 5231. Each second heat-conducting part 83 is respectively connected to a first heat-conducting part 81. The two second heat-conducting parts 83 are respectively connected to different positions of the extension section 512 of the same pole ear 51.

[0164] In these embodiments, each second heat-conducting portion 83 is respectively connected to a first heat-conducting portion 81, and the two second heat-conducting portions 83 are respectively connected to different positions of the extension section 512 of the same pole tab 51, so as to better improve the heat conduction rate at the pole tab 51 and improve the problem of affecting the performance of the battery cell 3 due to the excessive temperature at the pole tab 51.

[0165] The two second heat conducting portions 83 are respectively connected to different positions of the extension section 512 of the same tab 51 . Thus, the two second heat conducting portions 83 conduct heat to the same tab 51 to better balance the temperature of the tab 51 .

[0166] The two second heat conducting portions 83 are connected to different positions of the extension section 512, and each second heat conducting portion 83 can directly contact the extension section 512. The two second heat conducting portions 83 can be disposed on both sides of the extension section 512 in the first direction X, or the two second heat conducting portions 83 can be disposed on the same side of the extension section 512 in the first direction X.

[0167] Optionally, the two second heat conducting parts 83 are respectively connected to the extension section 512 of the same tab 51 on both sides of the first direction X, which can ensure that each second heat conducting part 83 has sufficient contact area with the extension section 512, thereby reducing the difficulty of connecting the second heat conducting part 83 and the extension section 512.

[0168] Optionally, two second heat conducting portions 83 provided on both sides of the electrode body 52 in the second direction Y are spaced apart along the second direction Y on a surface of the extension section 512 in the first direction X. For example, the two second heat conducting portions 83 are spaced apart along the second direction Y on the second sub-segment 5122.

[0169] Alternatively, the two second heat conducting portions 83 provided on both sides of the electrode body 52 in the second direction Y are spaced apart along the first direction X on both sides of the extension section 512 in the first direction X. For example, the two second heat conducting portions 83 are spaced apart along the first direction X in the second sub-segment 5122.

[0170] Optionally, the battery cell 3 includes a plurality of electrode assemblies 5 , and a first heat conducting portion 81 is disposed between adjacent electrode assemblies 5 .

[0171] In some embodiments, as Figure 9 and Figure 11 As shown, the extension section 512 includes a first sub-segment 5121, a second sub-segment 5122 and a third sub-segment 5123 that are spaced apart along the first direction X. The first sub-segment 5121 is connected to the retracted section 511, and the second sub-segment 5122 is connected to the adapter mechanism 7; one of the two second heat-conducting parts 83 is connected to the first sub-segment 5121, and the other is connected to the second sub-segment 5122.

[0172] In these embodiments, one of the two second heat-conducting parts 83 is connected to the first sub-segment 5121 , and the other is connected to the second sub-segment 5122 , and the connection areas between the two second heat-conducting parts 83 and the tab 51 are reasonably allocated to improve the connection reliability between the second heat-conducting parts 83 and the tab 51 .

[0173] Optionally, one second heat conducting portion 83 is connected to a side surface of the first sub-segment 5121 facing away from the second sub-segment 5122, and another second heat conducting portion 83 is connected to a side surface of the second sub-segment 5122 facing the first sub-segment 5121, so as to reduce the difficulty of connecting the tab 51 and the second heat conducting portion 83.

[0174] See also Figure 12 , Figure 12 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0175] In some embodiments, as Figure 9 and Figure 12 As 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 relative to each other in the second direction Y, and the two second side surfaces 5232 are arranged relative to each other in the third direction Z. The first direction X, the second direction and the third direction Z intersect. The area of ​​the first side surface 5231 is greater than the area of ​​the second side surface 5232. The adapter mechanism 7 includes a first connecting segment 71 and a second connecting segment 72 arranged along the third direction Z. The tab 51 is connected to the first connecting segment 71, and the second heat conducting portion 83 is connected to the second connecting segment 72.

[0176] In these embodiments, the adapter mechanism 7 includes a first connecting section 71 and a second connecting section 72, the pole ear 51 is connected to the first connecting section 71, and the second heat conducting portion 83 is connected to the second connecting section 72. The second heat conducting portion 83 is used to improve the heat conduction rate at the adapter mechanism 7, thereby improving the problem that the temperature at the adapter mechanism 7 is too high, thereby heating the pole piece and causing the performance of the battery cell 3 to be reduced.

[0177] The second heat conducting portion 83 is connected to the second connecting section 72, or the second heat conducting portion 83 and the electrode terminal 61 are both connected to the second connecting section 72. Specifically, the second heat conducting portion 83 is connected to the second connecting section 72, and the electrode terminal 61 and the tab 51 are connected to the first connecting section 71; or the second heat conducting portion 83 and the electrode terminal 62 are both connected to the second connecting section 72, and the second heat conducting portion 83 and the electrode terminal 62 are respectively provided on both side surfaces of the second connecting section 72 in the first direction X; or the second heat conducting portion 83 and the electrode terminal 62 are provided on one side surface of the second connecting section 72 in the first direction X.

[0178] Optionally, the specific size and shape of the first connecting section 71 and the second connecting section 72 can be designed by oneself.

[0179] Optionally, two second connecting sections 72 are provided on both sides of the first connecting section 71 , and two second heat conducting parts 83 are respectively connected to the two second connecting sections 72 to increase the contact area between the second heat conducting parts 83 and the adapter mechanism 7 .

[0180] Optionally, a pressure relief valve is provided on the top cover assembly 6 so that when the pressure inside the shell 4 reaches a threshold value, the pressure is released to the outside through the pressure relief valve. The shape and size of the adapter mechanism 7 can be designed by oneself, and the adapter mechanism 7 and the pressure relief valve are spaced apart to avoid the adapter mechanism 7 blocking the pressure relief valve.

[0181] Optionally, a single second connecting segment 72 can connect more than two second heat conducting parts 83 ; or the adapter mechanism 7 includes multiple second connecting segments 72 to connect multiple second heat conducting parts 83 to enhance the heat conducting efficiency of the heat conducting assembly 8 .

[0182] In some embodiments, as Figure 9 and Figure 12 As shown, two first heat-conducting parts 81 and two second heat-conducting parts 83 are respectively provided, the two first heat-conducting parts 81 are respectively provided on the two first side surfaces 5231, each second heat-conducting part 83 is respectively connected to one first heat-conducting part 81, and the two second heat-conducting parts 83 are respectively connected to different positions of the second connecting section 72 of the same adapter mechanism 7.

[0183] In these embodiments, the two first heat-conducting parts 81 are respectively arranged on the two first side surfaces 5231, each second heat-conducting part 83 is respectively connected to a first heat-conducting part 81, and the two second heat-conducting parts 83 are respectively connected to different positions of the second connecting section 72 of the same adapter mechanism 7, so as to better improve the heat conduction rate at the adapter mechanism 7 and improve the problem of affecting the performance of the battery cell 3 due to excessive temperature at the adapter mechanism 7.

[0184] The two second heat conducting portions 83 are connected to different positions of the same second connecting section 72, and each second heat conducting portion 83 can directly contact the second connecting section 72. The two second heat conducting portions 83 can be provided on both sides of the second connecting section 72 in the first direction X, or on the same side of the second connecting section 72 in the first direction X; or at both ends of the second connecting section 72 in the second direction Y; or at one end of the second connecting section 72 in the second direction Y.

[0185] Optionally, the two second heat-conducting parts 83 are respectively connected to the second connecting section 72 of the same adapter mechanism 7 on both sides of the second direction Y, thereby reducing the size of the second heat-conducting part 83, reducing the material cost of the second heat-conducting part 83, and reducing the difficulty of connecting the second heat-conducting part 83 and the adapter mechanism 7.

[0186] Optionally, two second connecting sections 72 are arranged on both sides of the first connecting section 71 in the second direction Y, and the two second connecting sections 72 have the same size. The two second heat conducting parts 83 are arranged on both sides of the electrode body 52 in the second direction Y and are respectively connected to the two second connecting sections 72.

[0187] Optionally, the positive electrode tab of the electrode body 52 and the second heat conducting portion 83 are connected to the same adapter mechanism 7 , or the negative electrode tab of the electrode body 52 and the second heat conducting portion 83 are connected to the same adapter mechanism.

[0188] Optionally, there are multiple electrode assemblies 5 , and one of the two second heat conducting portions 83 disposed on both sides of the electrode body 52 in the second direction Y is disposed between adjacent electrode assemblies 5 .

[0189] See also Figure 13 、 Figure 14 and Figure 15 , Figure 13 This is a partial structural diagram of a battery cell provided in one embodiment of the present application; Figure 14 yes Figure 13 Schematic diagram of the enlarged structure at B in the middle; Figure 15 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0190] In some embodiments, as Figure 6 and Figures 13 to 15As shown, two electrode assemblies 5 are provided, and the two electrode assemblies 5 are stacked along the second direction Y. The adapter mechanism 7 is provided with two first connecting sections 71, and the two first connecting sections 71 are respectively provided on both sides of the second connecting section 72 in the second direction Y. The pole ears 51 of the two electrode assemblies 5 are respectively connected to the two first connecting sections 71, and two first heat conducting parts 81 and second heat conducting parts 83 are respectively provided. The two first heat conducting parts 81 are respectively provided on the two first side surfaces 5231 of the same electrode body 52, and the two second heat conducting parts 83 are respectively connected to one end of the two first heat conducting parts 81 facing the adapter mechanism 7, and the two second heat conducting parts 83 are respectively connected to the two second connecting sections 72 of the adapter mechanism 7.

[0191] In these embodiments, the two first heat-conducting parts 81 are respectively arranged on both sides of an electrode body 52 in the second direction Y, the two second heat-conducting parts 83 are respectively connected to one end of the two first heat-conducting parts 81 facing the adapter mechanism 7, and the two second heat-conducting parts 83 are respectively connected to the two second connecting sections 72 of the adapter mechanism 7 to reduce the difficulty of connecting the second heat-conducting parts 83 and the pole ear 51 and the adapter mechanism 7; and the two second heat-conducting parts 83 are respectively connected to the pole ear 51 and the adapter mechanism 7 to better stabilize the temperature at the pole ear 51.

[0192] Figure 13 In order to facilitate observation of the connection relationship between the second heat conducting portion 83, the electrode tab 51 and the adapter mechanism 7, an electrode body 52 is hidden.

[0193] The adapter mechanism 7 is provided with two first connecting sections 71 , so that the adapter mechanism 7 can simultaneously connect the tabs of two electrode assemblies 5 , thereby reducing the overall size of the adapter mechanism 7 in the battery cell 3 and improving the energy density of the battery cell 3 .

[0194] The second connecting section 72 is located between the two first connecting sections 71 , and thus the second connecting section 72 is located between the two electrode assemblies 5 . One or more second heat conducting parts 83 are connected to the second connecting section 72 to conduct heat from the adapter 7 .

[0195] One or more second heat conducting portions 83 are located between the housing 4 and the tab 51 along the second direction Y. The second heat conducting portion 83 is connected to the tab 51 to conduct heat from the tab 51, thereby balancing the temperature of the tab 51 and improving the problem of the tab 51 heating the electrode body 52. ​​Exemplarily, the second heat conducting portion 83 is connected to the first sub-segment 5121 of the tab 51.

[0196] Optional, such as Figure 15As shown, the heat-conducting component 8 includes three first heat-conducting parts 81 and three second heat-conducting parts 83 arranged at intervals. The two first heat-conducting parts 81 are respectively arranged between the two first side surfaces 5231 of the electrode assembly 5 and the shell 4. The two first heat-conducting parts 81 are connected to the electrode ear 51 through two second heat-conducting parts 83; one first heat-conducting part 81 is connected to the second connecting section 72 through one second heat-conducting part 83 to enhance the heat conduction rate of the heat-conducting component 8.

[0197] See also Figure 16 、 Figure 17 and Figure 18 , Figure 16 This is a partial structural diagram of a battery cell provided in one embodiment of the present application; Figure 17 This is a partial structural diagram of a battery cell provided in one embodiment of the present application; Figure 18 This is a partial structural diagram of a battery cell provided in one embodiment of the present application.

[0198] In some embodiments, as Figure 6 、 Figures 16 to 18 As shown, the heat conducting assembly 8 further includes a third heat conducting portion 82 , which is disposed between the housing 4 and at least a portion of the second end surface 522 along the first direction X, and is connected to the first heat conducting portion 81 .

[0199] In these embodiments, the heat-conducting component 8 also includes a third heat-conducting portion 82 arranged between the shell 4 and at least a portion of the second end surface 522 along the first direction X. The third heat-conducting portion 82 is connected to the first heat-conducting portion 81 to increase the contact area between the heat-conducting component 8 and the shell 4, so as to increase the heat conduction rate of the heat-conducting component 8 to the pole tab 51, thereby improving the problem of affecting the performance of the battery cell 3 due to the excessively high temperature at the pole tab 51.

[0200] The third heat-conducting part 82 is connected to the first heat-conducting part 81. Specifically, the heat-conducting assembly 8 includes an insulating part (not shown in the figure) and a heat-conducting part (not shown in the figure). At least part of the insulating part forms an accommodating cavity, and the heat-conducting part is arranged in the accommodating cavity. Then the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the third heat-conducting part 82 are connected. Exemplarily, the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the third heat-conducting part 82 are integrally formed or bonded to each other or abutted against each other; or the heat-conducting part in the first heat-conducting part 81 and the heat-conducting part in the third heat-conducting part 82 are spaced apart, and the insulating part of the first heat-conducting part 81 and the insulating part of the third heat-conducting part 82 are connected to each other.

[0201] The heat at the tab 51 can be transferred to the third heat conducting portion 82 through the second heat conducting portion 83 and the first heat conducting portion 81, and then transferred to the external environment at the third heat conducting portion 82. The interconnected first heat conducting portion and the third heat conducting portion 82 increase the heat exchange area of ​​the heat conducting component 8 and improve the heat conduction rate of the heat conducting component 8.

[0202] Optionally, the heat exchange mechanism is provided along the first direction X at an end of the battery cell 3 where no tab 51 is provided, and the third heat conducting portion 82 can transfer heat between the heat exchange mechanism and the tab 51 .

[0203] Optionally, the third heat conducting portion 82 covers the entire second end surface 522 of the electrode assembly 5 to improve the heat conduction rate of the third heat conducting portion 82 .

[0204] Optionally, the shape and size of the third heat conducting portion 82 can be flexibly designed. For example, the third heat conducting portion 82 is rectangular or circular.

[0205] Optionally, the first heat conducting portion 81, the third heat conducting portion 82 and the second heat conducting portion 83 are integrally formed to improve the heat conduction rate of the heat conducting component 8. For example, Figure 17 As shown, the first heat conducting part 81 is arranged on the first side surface 5231, and at least two second heat conducting parts 83 are spaced apart at one end of the first heat conducting part 81 in the first direction X. The first heat conducting part 81 is connected to the third heat conducting part 82 at the other end in the first direction X, thereby improving the heat conducting efficiency of the heat conducting component 8 and reducing the processing difficulty of the heat conducting component 8.

[0206] Optional, such as Figure 16 and Figure 18 As shown, the two first heat-conducting parts 81 are arranged at intervals, and the two first heat-conducting parts 81 are connected to the second heat-conducting part 83 at one end in the first direction X. The two first heat-conducting parts 81 are connected through the third heat-conducting part 82 at the other end in the first direction X, so that the third heat-conducting part 82 can balance the heat of the two first heat-conducting parts 81.

[0207] See also Figure 19 , Figure 19 This is an exploded view of a battery cell provided in another embodiment of the present application.

[0208] In some embodiments, as Figure 19 As shown, the tab 51 extends out of the first end face 521 , and the battery cell 3 further includes a first insulating film 91 , which covers the side face 523 and the second end face 522 of the electrode body 52 ; wherein the first heat conducting portion 81 is located between the first insulating film 91 and the electrode assembly 5 , or the first heat conducting portion 81 is located between the first insulating film 91 and the shell 4 .

[0209] In these embodiments, the first insulating film 91 is covered on the side surface 523 and the second end surface of the electrode body 52 to insulate the shell 4 and the electrode assembly 5. The first heat-conducting part 81 is located between the first insulating film 91 and the electrode assembly 5. The first insulating film 91 plays a role in supporting and protecting the first heat-conducting part 81, reducing the problem of damage to the first heat-conducting part 81 under external force impact, or the first heat-conducting part 81 is located between the first insulating film 91 and the shell 4 to improve the insulation reliability between the first heat-conducting part 81 and the electrode assembly 5, and improve the thermal conductivity efficiency between the first heat-conducting part 81 and the shell 4.

[0210] For example, the material of the first insulating film 91 may be PP or PI (polyimide) or PET (polyethylene terephthalate).

[0211] The first heat conducting portion 81 is located between the first insulating film 91 and the electrode assembly 5 , which helps to reduce the distance between the first heat conducting portion 81 and the electrode assembly 5 and improve the heat conduction rate between the electrode assembly 5 and the first heat conducting portion 81 .

[0212] Optionally, a groove is formed on the first insulating film 91 , and the first heat conducting portion 81 is accommodated in the groove, so as to reduce the overall thickness of the first insulating film 91 and the first heat conducting portion 81 .

[0213] The first heat conducting part 81 is located between the first insulating film 91 and the housing 4 . At least one of the first insulating film 91 and the housing 4 is bonded to the first heat conducting part 81 to keep the first heat conducting part 81 stable in the housing 4 .

[0214] See also Figure 20 , Figure 20 Schematic diagram of the structure of a heat-conducting component of a battery cell provided in one embodiment of the present application.

[0215] In some embodiments, as Figure 6 and Figure 20 As shown, the heat-conducting assembly 8 includes an insulating member 85 and a heat-conducting member 84. At least a partial area of ​​the insulating member 85 forms a receiving cavity 851. The heat-conducting member 84 is arranged in the receiving cavity 851. The heat-conducting member 84 includes a first heat-conducting sheet 841 and a second heat-conducting sheet 842. The first heat-conducting portion 81 is composed of the first heat-conducting sheet 841 and the insulating member 85. The second heat-conducting portion 83 is composed of the second heat-conducting sheet 842 and the insulating member 85. The first heat-conducting sheet 841 and the second heat-conducting sheet 842 are connected.

[0216] In these embodiments, the heat-conducting component 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 arranged in the receiving cavity 851. The heat-conducting member 84 is used to improve the heat-conducting capacity of the heat-conducting component 8. The heat-conducting member 84 includes a first heat-conducting sheet 841 and a second heat-conducting sheet 842. The first heat-conducting sheet 841 and the insulating member 85 form a first heat-conducting portion 81. The second heat-conducting sheet 842 and the insulating member 85 form a second heat-conducting portion 83. The first heat-conducting sheet 841 and the second heat-conducting sheet 842 are connected. In this way, when the first heat-conducting sheet 841 and the second heat-conducting sheet 842 are combined to conduct heat, the first heat-conducting sheet 841 and the second heat-conducting sheet 842 are insulated from the electrode assembly 5 by the insulating member 85, and the insulating member 85 can isolate the heat-conducting member 84 and the electrolyte to improve the problem that the heat-conducting member 84 and the electrolyte are incompatible, thereby affecting the performance of the battery cell 3.

[0217] For example, the insulating member 85 may be made of PP, PI, or PET, etc. The heat conducting member 84 may be made of graphite, graphene, or carbon nanotubes, etc. The heat conductivity of the heat conducting member 84 is greater than that of the housing 4 .

[0218] Optionally, the heat conducting member 84 may be in a plate-like, strip-like, or mesh-like shape. For example, a plate-like heat conducting member, a mesh-like heat conducting member, or one or more strip-like heat conducting members arranged at intervals are provided in the accommodating cavity 851 .

[0219] Optionally, the insulating member 85 is provided with a accommodating cavity 851 with an opening 41 at one end, the heat conductive member 84 is arranged in the accommodating cavity 851, and the opening of the insulating member 85 is bonded or welded 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 independent sub-insulating layers arranged opposite to each other, and the edges of the two sub-insulating layers are bonded or welded so that the heat conductive member 84 is located in a sealed accommodating cavity 851.

[0220] 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.

[0221] At least a portion of the insulating member 85 extends from the side surface 523. The first heat conducting sheet 841 is disposed on the side surface 523 and is thermally connected to the electrode assembly 5. The first heat conducting portion 81 is composed of the first heat conducting sheet 841 and the insulating member 85. Exemplarily, the first heat conducting sheet 841 covers the entire side surface 523 to improve the heat conduction rate of the first heat conducting portion 81.

[0222] In some embodiments, as Figure 6 and Figure 20 As shown, the heat conductor 84 includes graphite, graphene, or carbon nanotubes.

[0223] Graphite is typically composed of parallel layers of carbon atoms, forming a flat sheet. Graphene is typically a two-dimensional crystal of carbon atoms, only one atom thick on one side, and has a fibrous shape. Carbon nanotubes are typically tubular structures formed by curling one or more layers of graphite.

[0224] In these embodiments, the material of the heat conducting member 84 includes graphite, graphene, or carbon nanotubes, and the heat conducting performance of the heat conducting member 84 is improved by using the graphite, graphene, or carbon nanotube heat conducting materials.

[0225] 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.

[0226] 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.

[0227] In some embodiments, as Figure 6 and Figure 20 As shown, the thermal conductivity k of the heat conducting member 84 satisfies k≥500 W / (m·K).

[0228] 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 of the electrode body 52 .

[0229] Optionally, the thermal conductivity k of the heat conductor 84 satisfies 500W / (m·K)≤k≤1600W / (m·K). For example, the thermal conductivity of the heat conductor 84 is 500W / (m·K) or 550W / (m·K) or 1050W / (m·K) or 1550W / (m·K) or 1600W / (m·K), etc.

[0230] Optionally, the thermal conductivity k of the heat conducting member 84 satisfies k≥1000 W / (m·K).

[0231] 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.

[0232] 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.

[0233] 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.

[0234] In some embodiments, as Figures 1 to 20 As shown, the battery cell 3 includes a shell 4, an electrode assembly 5 and a heat-conducting assembly 8. The electrode assembly 5 is located in the shell 4. The electrode assembly 5 is 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 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 side face 523 includes two first side faces 5231 and two second side faces 5232. The two first side faces 5231 are arranged opposite to each other in the second direction Y, and the two second side faces 523 are arranged opposite to each other in the 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. The tab 51 is connected to the electrode body 52 and extends out from the first end Surface 521; the heat-conducting assembly 8 includes a first heat-conducting portion 81, a second heat-conducting portion 83 and a third heat-conducting portion 82, 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 an accommodating cavity 851, the heat-conducting member 84 is disposed in the accommodating cavity 851, the heat-conducting member 84 includes a first heat-conducting sheet 841 and a second heat-conducting sheet 842, the first heat-conducting portion 81 is composed of the first heat-conducting sheet 841 and the insulating member 85, the second heat-conducting portion 83 is composed of the second heat-conducting sheet 842 and the insulating member 85, the first heat-conducting sheet 841 and the second heat-conducting sheet 842 are connected, the first heat-conducting portion 81 is thermally connected to the first side surface 5231, the thermal conductivity of the heat-conducting assembly 8 is greater than the thermal conductivity of the housing 4, the third heat-conducting portion 82 is disposed along the first direction X between the housing 4 and at least a portion of the second end surface 522, and the third heat-conducting portion 82 is connected to the first heat-conducting portion 81;

[0235] The shell 4 includes an opening 41 in the first direction X, and the battery cell 3 also includes a top cover assembly 6 and a switching mechanism 7. The top cover assembly 6 covers the opening 41. The top cover assembly 6 has an electrode terminal 61. The switching mechanism 7 is connected between the pole ear 51 and the top cover assembly 6. At least one of the pole ear 51 and the switching mechanism 7 is connected to the second heat conducting portion 83. The second heat conducting portion 83 is connected to the first heat conducting portion 81. There are two electrode assemblies 5. The two electrode assemblies 5 are stacked along the second direction Y. The switching mechanism 7 is provided with two first connecting segments 71. The two first connecting segments 71 are respectively provided on both sides of the second connecting segment 72 in the second direction Y. The pole ears 51 of the two electrode assemblies 5 are respectively connected to the two first connecting segments 71. There are two first heat conducting portions 81 and the second heat conducting portions 83 respectively. The two first heat conducting portions 81 are respectively provided. On both sides of an electrode body 52 in the second direction Y, the two second heat-conducting portions 83 are respectively connected to one end of the two first heat-conducting portions 81 facing the adapter mechanism 7, and the two second heat-conducting portions 83 are respectively connected to the two second connecting segments 72 of the adapter mechanism 7. The extension segment 512 includes a first sub-segment 5121, a second sub-segment 5122, and a third sub-segment 5123 connecting the first sub-segment 5121 and the second sub-segment 5122, which are arranged at intervals along the first direction X. The first sub-segment 5121 is connected to the retracted segment 511, and the second sub-segment 5122 is connected to the adapter mechanism 7. The second heat-conducting portion 83 is connected to one side of the first sub-segment 5121 facing the retracted segment 511. The heat-conducting member 84 includes graphite, graphene, or carbon nanotubes. The thermal conductivity k of the heat-conducting member 84 satisfies k>500W / (m·K).

[0236] 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 tab 51. The electrode body 52 includes a first end face 521 and a second end face 522 that are oppositely arranged 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 tab 51 extending from the first end face 521 and / or the second end face 522. The thermal conductivity of the heat-conducting assembly 8 is greater than that of the shell 4. The heat-conducting assembly 8 includes a first heat-conducting portion 81. The first heat-conducting portion 81 that is thermally connected to the side face 523 of the electrode body 52 can reduce the electrode body 52 on its side face 523. 23, improve the temperature uniformity of the electrode body 52 at its side 523, and improve the rate of heat exchange between the electrode body 52 and the external environment at its side 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. The top cover assembly 6 covers the opening 41 of the shell 4, and the pole ear 51 and the electrode terminal 61 of the top cover assembly 6 are connected to achieve electrical connection. The heat-conducting assembly 8 also includes a second heat-conducting part 83 that is heat-conductingly connected to the pole ear 51, and the second heat-conducting part 83 is heat-conductingly connected to the first heat-conducting part 81, so that the heat-conducting assembly 8 can improve the heat conduction rate at the pole ear 51, so as to balance the temperature at the pole ear 51, and improve the problem that the performance of the battery cell 3 is affected by the high temperature at the pole ear 51.

[0237] 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; The heat conducting component includes a first heat conducting portion, the first heat conducting portion is heat-conductingly connected to the side surface, the heat conductivity of the heat conducting component is greater than the heat conductivity of the shell, and the heat conducting component and the electrode assembly are insulated from each other. In which, the shell includes an opening in the first direction, the battery cell also includes a top cover assembly, the top cover assembly covers the opening, the top cover assembly has an electrode terminal, the electrode terminal is connected to the tab, the heat conductive assembly also includes a second heat conductive part, the second heat conductive part is thermally connected to the tab, and the second heat conductive part is thermally connected to the first heat conductive part.

2. The battery cell according to claim 1, wherein: The battery cell further includes a switching mechanism connected between the tab and the electrode terminal, and the second heat conducting portion is also heat-conductingly connected to the switching mechanism.

3. The battery cell according to claim 2, characterized in that: The electrode tab includes a retracted section and an extended section, the retracted section is connected to the electrode body, one side of the extended section is connected to the retracted section, and the other side is connected to the adapter mechanism, the second heat conducting portion is connected to the side of the extended section facing the retracted section, or the second heat conducting portion is connected to the side of the extended section facing the adapter mechanism.

4. The battery cell according to claim 3, characterized in that The extension section includes a first sub-segment and a second sub-segment spaced apart along the first direction, and a third sub-segment connecting the first sub-segment and the second sub-segment, the first sub-segment is connected to the gathering section, the second sub-segment is connected to the transfer mechanism, and the second heat-conducting portion is connected to a side of the first sub-segment facing the gathering section.

5. The battery cell according to claim 3, 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, the area of ​​the first side surface is larger than the area of ​​the second side surface, and the two tabs are provided, the two tabs extend from the first end surface, and are spaced apart along the third direction. Two of the first heat conducting parts and two of the second heat conducting parts are respectively provided, the two first heat conducting parts are respectively provided on the two second side surfaces, the two second heat conducting parts are respectively connected to the ends of the two first heat conducting parts facing the tabs, and the two second heat conducting parts are respectively connected to the extension sections of the two tabs.

6. The battery cell according to claim 3, 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. Two of the first heat conducting parts and two of the second heat conducting parts are respectively provided, the two first heat conducting parts are respectively provided on the two first side surfaces, each of the second heat conducting parts is respectively connected to one of the first heat conducting parts, and the two second heat conducting parts are respectively connected to different positions of the extension section of the same tab.

7. The battery cell according to claim 6, characterized in that The extension section includes a first sub-segment and a second sub-segment spaced apart along the first direction, and a third sub-segment connecting the first sub-segment and the second sub-segment, the first sub-segment is connected to the gathering section, and the second sub-segment is connected to the transition mechanism; One of the two second heat conducting parts is connected to the first sub-segment, and the other is connected to the second sub-segment.

8. 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 transfer mechanism includes a first connecting section and a second connecting section arranged along the third direction. The tab is connected to the first connecting section, and the second heat conducting portion is connected to the second connecting section.

9. The battery cell according to claim 8, characterized in that There are two of the first heat conducting parts and two of the second heat conducting parts, respectively. The two first heat conducting parts are respectively arranged on the two first side surfaces, each of the second heat conducting parts is respectively connected to one of the first heat conducting parts, and the two second heat conducting parts are respectively connected to different positions of the second connecting section of the same adapter mechanism.

10. The battery cell according to claim 8, characterized in that There are two electrode assemblies, and the two electrode assemblies are stacked along the second direction. The switching mechanism is provided with two first connecting segments, and the two first connecting segments are respectively provided on both sides of the second connecting segment in the second direction. The tabs of the two electrode assemblies are respectively connected to the two first connecting segments. Two of the first heat conducting parts and two of the second heat conducting parts are respectively provided, the two first heat conducting parts are arranged on the two first side surfaces of the same electrode body, the two second heat conducting parts are respectively connected to one end of the two first heat conducting parts facing the adapter mechanism, and the two second heat conducting parts are respectively connected to the second connecting section of the adapter mechanism and the electrode ear.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The tab extends out of the first end surface. The heat-conducting assembly further includes a third heat-conducting portion, which is arranged along the first direction between the housing and at least a portion of the second end surface. The third heat-conducting portion is connected to the first heat-conducting portion.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The tab extends out from the first end face, and the battery cell further includes a first insulating film, which covers the side face and the second end face of the electrode body; wherein the first heat-conducting portion is located between the first insulating film and the electrode assembly, or the first heat-conducting portion is located between the first insulating film and the shell.

13. The battery cell according to any one of claims 1 to 12, characterized in that: The heat-conducting assembly includes an insulating member and a heat-conducting member, wherein at least a portion of the insulating member forms a receiving cavity, and the heat-conducting member is disposed in the receiving cavity. The heat conducting member includes a first heat conducting sheet and a second heat conducting sheet. The first heat conducting portion is composed of the first heat conducting sheet and the insulating member. The second heat conducting portion is composed of the second heat conducting sheet and the insulating member. The first heat conducting sheet and the second heat conducting sheet are connected.

14. The battery cell according to claim 13, characterized in that The heat conducting member includes graphite, graphene or carbon nanotubes.

15. The battery cell according to claim 13, characterized in that The thermal conductivity k of the heat conducting member satisfies k≥500 W / (m·K).

16. A battery device, characterized in that: The battery cell comprises the battery cell according to any one of claims 1 to 15.

17. An electrical device, characterized in that: A battery device comprising the battery device described in claim 16.

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