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 monomer comprises a shell, an electrode assembly and a heat conduction assembly, the electrode assembly is located in the shell, the heat conduction assembly comprises an insulating part and a heat conduction part, the insulating part is arranged around the circumferential side of an electrode main body to improve the insulation reliability of the side face and the shell, and the heat conduction part is arranged in a containing cavity of the insulating part to enable the heat conduction part to be insulated from the electrode main body through the insulating part; the heat conduction piece is arranged around the peripheral side of the electrode body, the heat exchange rate of the side face of the electrode body and the external environment is improved, the heat conduction piece is provided with a gap extending in the first direction and penetrating through the gap, and the elastic deformation capacity of the heat conduction piece is enhanced through the gap so that the heat conduction piece can deform synchronously along with the electrode assembly. The extrusion force between the heat-conducting member and the electrode main body is reduced, the risk of damage caused by mutual extrusion of the heat-conducting member and the electrode main body is reduced, the service life of the heat-conducting assembly is prolonged, and the reliability of the battery monomer is improved.

Description

Technical Field

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

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

[0003] In actual operation, excessively high or low internal temperatures of a battery cell can adversely affect its lifespan and performance. Therefore, related technologies typically incorporate heat-conducting components within the battery cell to stabilize the temperature of the electrode assembly. However, improving the lifespan of these heat-conducting components is a pressing issue that needs to be addressed. Utility Model Content

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the service life of the heat-conducting components and enhance their reliability.

[0005] In a first aspect, this application provides a battery cell, comprising: a housing; an electrode assembly located within the housing, the electrode assembly including an electrode body and tabs connected to each other, the electrode body including a first end face and a second end face disposed opposite to each other in a first direction, and a side face connected between the first end face and the second end face, the tabs extending out of at least one of the first end face and the second end face; and a heat-conducting assembly including an insulating member and a heat-conducting member, the insulating member forming a receiving cavity in at least a portion of its area, the heat-conducting member being disposed within the receiving cavity, the insulating member and the heat-conducting member being disposed around the periphery of the electrode body, the heat-conducting member having a gap extending along the first direction and penetrating the heat-conducting member.

[0006] In the embodiments of this application, the battery cell includes a housing, an electrode assembly, and a heat-conducting assembly. The electrode assembly is located inside the housing and includes an electrode body and tabs connected to each other. The electrode body includes a first end face, a second end face, and a side face. The heat-conducting assembly includes an insulating member and a heat-conducting member. The insulating member is arranged around the periphery of the electrode body to reduce the splicing seams on the insulating member, thereby improving the insulation reliability between the side face and the housing. The heat-conducting member is disposed within the receiving cavity of the insulating member so that the heat-conducting member is insulated from the electrode body through the insulating member. The heat-conducting member is arranged around the periphery of the electrode body to increase the side contact area between the heat-conducting member and the electrode body, thereby improving the heat exchange rate between the electrode body and the external environment at its side face. The heat-conducting member is provided with a gap extending and penetrating in a first direction. By providing a gap, the elastic deformation capability of the heat-conducting member is enhanced, so that the heat-conducting member can deform synchronously with the electrode assembly, reducing the compressive force between the heat-conducting member and the electrode body, reducing the risk of mutual compression damage between the heat-conducting member and the electrode body, improving the service life of the heat-conducting assembly, and improving the reliability of the battery cell.

[0007] In some embodiments, the side includes two first side surfaces and two second side surfaces, the two first side surfaces are disposed opposite each other in a second direction, the two second side surfaces are disposed opposite each other in a 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 at least a portion of the gap in the electrode assembly is projected onto the second side surface.

[0008] In the embodiment of this application, the gap is projected at least partially onto the second side of the electrode assembly to reduce the extrusion pressure on the end of the heat-conducting component and the electrode assembly during the expansion of the electrode assembly. This improves the problem of stress concentration at the end of the heat-conducting component during the expansion of the electrode assembly, which leads to uneven ion distribution and increased risk of lithium plating, thereby improving the reliability of the battery cell.

[0009] In some embodiments, a heat-conducting element is wound around at least one electrode body, and a gap is formed between the two ends of the heat-conducting element.

[0010] In the embodiments of this application, a heat-conducting element is wound around at least one electrode body to increase the side contact area between the heat-conducting element and the electrode body, thereby improving the heat exchange rate between the electrode body and the external environment at its side. A gap is formed between the two ends of the heat-conducting element to reduce the processing difficulty of the heat-conducting component.

[0011] In some embodiments, the heat-conducting component includes a first heat-conducting portion, a second heat-conducting portion, and a third heat-conducting portion. The two first heat-conducting portions are disposed on two first side surfaces, and the second and third heat-conducting portions are disposed on two second side surfaces. The second heat-conducting portion is connected to the two first heat-conducting portions, and the third heat-conducting portion is connected to one first heat-conducting portion and spaced apart from the other first heat-conducting portion to form a gap. Alternatively, the two third heat-conducting portions are respectively connected to the two first heat-conducting portions, and the two third heat-conducting portions are spaced apart in a second direction to form a gap.

[0012] In the embodiment of this application, the third heat-conducting part is connected to a first heat-conducting part and is spaced apart from another first heat-conducting part to form a gap. The third heat-conducting part is disposed on the second side, which not only helps to increase the contact area between the heat-conducting component and the side and improve the heat conduction efficiency of the heat-conducting component, but also absorbs some of the matching errors between the heat-conducting component and the electrode component through the third heat-conducting part, reducing the difficulty of setting the heat-conducting component.

[0013] In some embodiments, at least two electrode assemblies are provided, and the at least two electrode assemblies are stacked along a second direction. The heat-conducting element extends continuously and forms two heat-conducting structures arranged along the second direction. The heat-conducting structures are wrapped around at least one electrode body, and the ends and middle regions of at least one heat-conducting element are spaced apart to form a gap.

[0014] In the embodiment of this application, the heat-conducting element extends continuously and forms two heat-conducting structures arranged along the second direction. The heat-conducting structures are wrapped around at least one electrode body so that a single heat-conducting component can provide insulation and heat conduction for more electrode bodies. This helps to reduce the overall size of the heat-conducting component and save the material cost of the battery cell. The end and middle regions of at least one heat-conducting element are spaced apart to form a gap to reduce the risk of mutual compression and damage between the heat-conducting element and the electrode assembly.

[0015] In some embodiments, the heat-conducting component includes a first heat-conducting portion, two second heat-conducting portions, and two third heat-conducting portions. The first heat-conducting portion includes a middle heat-conducting portion and two end heat-conducting portions. The middle heat-conducting portion is disposed between the two end heat-conducting portions along a second direction. The end heat-conducting portions and the middle heat-conducting portion are disposed on both sides of the electrode assembly. The middle heat-conducting portion is disposed between two adjacent first sides of two adjacent electrode assemblies. The second heat-conducting portions and the third heat-conducting portions are disposed at both ends of the same end heat-conducting portion in a third direction. The two second heat-conducting portions are respectively connected to both ends of the middle heat-conducting portion in a third direction. The third heat-conducting portions and the middle heat-conducting portion are spaced apart to form a gap. The end heat-conducting portions and the second and third heat-conducting portions connected thereto, as well as the middle heat-conducting portion, form the same heat-conducting structure.

[0016] In the embodiment of this application, the central heat-conducting element is disposed between two adjacent first sides of two adjacent electrode assemblies, so that the heat between adjacent battery cells can be transferred to the outside through the central heat-conducting element and the second heat-conducting element. This helps to balance the temperature of the battery cells. The second heat-conducting element, the end heat-conducting element and the third heat-conducting element are respectively arranged around the electrode assembly in cooperation with the central heat-conducting element. By sharing the central heat-conducting element, the overall size of the heat-conducting assembly is reduced, saving the material cost of the battery cells.

[0017] In some embodiments, multiple electrode assemblies are provided, and the multiple electrode assemblies are stacked along a second direction. The battery cell includes at least two heat-conducting components spaced apart along the second direction, and the at least two heat-conducting components are respectively disposed on at least two electrode assemblies.

[0018] In the embodiments of this application, multiple electrode components are stacked along the second direction to increase the capacity of a single battery cell, and at least two heat-conducting components are respectively wound around at least two electrode components to reduce the difficulty of matching the heat-conducting components and electrode components.

[0019] In some embodiments, at least two gaps are disposed on either side of the electrode assembly in a third direction.

[0020] In the embodiments of this application, at least two gaps are respectively disposed on both sides of the electrode assembly in the third direction, so as to balance the restraining force on the multiple electrode assemblies arranged along the second direction at both ends of the third direction and to balance the degree of deformation of the multiple electrode assemblies at both ends of the third direction.

[0021] In some embodiments, the side includes two first side surfaces and two second side surfaces, the two first side surfaces are disposed opposite each other in a second direction, the two second side surfaces are disposed opposite each other in a third direction, the first direction, the second direction and the third direction intersect each other, the thermal conductive component also includes an adhesive layer, the insulating member is bonded to the first side surface through the adhesive layer, and the adhesive layer is spaced apart at the edges of the third direction and the first side surface.

[0022] In the embodiment of this application, the adhesive layer is spaced apart at the edges of the third direction and the first side, so that the insulating component forms a deformation space between the edges of the adhesive layer and the first side, so as to facilitate the deformation of the heat-conducting component and the electrode component together during the expansion of the battery cell, and reduce the risk of mutual compression and damage between the electrode component and the heat-conducting component during the expansion process.

[0023] In some embodiments, the housing includes an opening in a first direction, the battery cell further includes an end cap assembly that closes to the opening and is connected to a tab, and at least a portion of the insulating member extends out of a first end face in the first direction and is connected to the end cap assembly.

[0024] In the embodiments of this application, at least a portion of the insulating member extends out of the first end face in the first direction and is connected to the end cap assembly, so that the end cap assembly plays a role in positioning and fixing the heat-conducting component, thereby improving the stability of the heat-conducting component within the housing.

[0025] In some embodiments, the tabs extend from the first end face, and the battery cell further includes an insulation mechanism disposed on the second end face and connected to the insulation member.

[0026] In the embodiments of this application, the insulating mechanism disposed on the second end face helps to enhance the insulation performance between the second end face and the housing. The insulating element and the insulating mechanism are connected to make the heat-conducting component more reliably insulate the electrode assembly and the housing.

[0027] Secondly, embodiments of this application provide a battery device including a battery cell from any of the embodiments of the first aspect described above.

[0028] Thirdly, embodiments of this application provide an electrical device, including the battery device described in the second aspect of the embodiment above. Attached Figure Description

[0029] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0030] Figure 1This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0031] Figure 2 This is a schematic diagram of the structure of a battery device provided in an embodiment of this application;

[0032] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of the application;

[0033] Figure 4 This is an exploded view of a single battery cell provided in an embodiment of this application;

[0034] Figure 5 This is a schematic diagram of the electrode assembly of a battery cell provided in an embodiment of this application;

[0035] Figure 6 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in an embodiment of this application;

[0036] Figure 7 yes Figure 6 Sectional view at point AA;

[0037] Figure 8 This is a partial structural schematic diagram of a battery cell provided in an embodiment of this application;

[0038] Figure 9 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application;

[0039] Figure 10 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in an embodiment of this application;

[0040] Figure 11 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application;

[0041] Figure 12 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application;

[0042] Figure 13 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application;

[0043] Figure 14 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application;

[0044] Figure 15 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application;

[0045] Figure 16 This is an exploded view of a single battery cell provided in another embodiment of this application;

[0046] Figure 17 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application;

[0047] Figure 18 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application.

[0048] Figure label:

[0049] 1. Vehicle; 101. Motor; 102. Controller; 2. Battery Unit; 201. Battery Module; 202. Housing; 2021. First Housing; 2022. Second Housing;

[0050] 3. Battery cells;

[0051] 4. Shell;

[0052] 5. Electrode assembly; 51. Electrode tab; 52. Electrode body; 521. First end face; 522. Second end face; 523. Side face; 5231. First side face; 5232. Second side face;

[0053] 6. End cap assembly;

[0054] 7. Thermally conductive component; 71. Insulating component; 72. Thermally conductive component; 74. Adhesive layer; 75. Gap; 711. Receiving cavity; 712. Sub-insulating layer; 721. First thermally conductive part; 722. Second thermally conductive part; 723. Third thermally conductive part; 7211. Middle thermally conductive component; 7212. End thermally conductive component; 724. Thermally conductive structure;

[0055] 8. Insulation mechanism;

[0056] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0057] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0058] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0059] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0060] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0061] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0062] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0063] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery device applications, market demand is also constantly increasing.

[0064] To balance the temperature of individual battery cells, heat-conducting components can be installed inside the cells, but these components are prone to cracking and deformation.

[0065] The reason for the above problem is that the heat-conducting component includes an insulating component and a heat-conducting component disposed within the insulating component. The heat-conducting component is wound around the electrode component. During the expansion of the electrode component, the heat-conducting component has poor deformation ability. The electrode component and the heat-conducting component are subjected to strong extrusion pressure. The heat-conducting component is prone to cracking and deformation due to excessive stress.

[0066] To address the aforementioned issues, this application provides a battery cell comprising a housing, an electrode assembly, and a heat-conducting assembly. The electrode assembly is located within the housing and includes interconnected electrode bodies and tabs. The electrode body includes a first end face, a second end face, and a side face. The heat-conducting assembly includes an insulating component and a heat-conducting component. The insulating component is arranged around the periphery of the electrode body, reducing seams on the insulating component to improve the insulation reliability between the side face and the housing. The heat-conducting component is disposed within the cavity of the insulating component, allowing it to insulate against the electrode body through the insulating component. The heat-conducting component is arranged around the periphery of the electrode body to increase the side contact area between the heat-conducting component and the electrode body, thereby improving the heat exchange rate between the electrode body and the external environment at its side face. The heat-conducting component has a gap extending and penetrating in a first direction. This gap enhances the elastic deformation capability of the heat-conducting component, facilitating synchronous deformation of the heat-conducting component with the electrode assembly, reducing the compressive force between the heat-conducting component and the electrode body, reducing the risk of mutual compression damage between the heat-conducting component and the electrode body, improving the service life of the heat-conducting assembly, and enhancing the reliability of the battery cell.

[0067] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0068] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical devices.

[0069] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0070] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application embodiment is not limited to this. The battery cell can be cylindrical, flat, cuboid, or other shapes, and this application embodiment is not limited to this either.

[0071] The battery device mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery device mentioned in this application may include a battery module or a battery pack. A battery pack generally includes a housing for encapsulating one or more battery cells. The housing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0072] A single battery cell includes electrode components and an electrolyte. The electrode components include a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode components. The positive electrode includes a positive current collector and a positive active material layer, the latter coated on the surface of the current collector. The current collector includes a positive current-collecting section and a positive electrode tab connected to it. The current-collecting section is coated with the positive active material layer, while the tab is not. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material layer includes the positive active material, which 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, the negative active material layer being coated on the surface of the negative current collector. The negative current collector includes a negative current collection section and a negative electrode tab connected to the negative current collection section. The negative current collection section is coated with the negative active material layer, while the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0073] It should be understood that the technical solutions described in the embodiments of this application are not limited to the battery devices and electrical equipment described above, but can also be applied to all battery devices including housings and electrical equipment using battery devices. However, for the sake of brevity, the following embodiments are all illustrated using electric vehicles as examples.

[0074] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1 provided in some embodiments of this application. Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc. A battery device 2 is installed inside vehicle 1, and the battery device 2 can be located at the bottom, front, or rear of vehicle 1. The battery device 2 can be used to power vehicle 1; for example, the battery device 2 can serve as the operating power source for vehicle 1. Vehicle 1 may also include a controller 102 and a motor 101. The controller 102 is used to control the battery to supply power to the motor 101, for example, to meet the power needs of vehicle 1 during starting, navigation, and driving.

[0075] In some embodiments of this application, the battery device 2 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0076] Figure 2 A schematic diagram of the structure of a battery device according to an embodiment of this application is shown.

[0077] The battery device 2 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 3, which are connected in series, parallel, or mixed connections via a busbar.

[0078] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of battery cells 3.

[0079] As an example, the battery cell assembly can be a battery module 201, which is formed by arranging and fixing multiple battery cells 3 to form an independent module. As an example, the battery module 201 can be formed by binding multiple battery cells 3 together with cable ties.

[0080] In some embodiments, the battery device may be a battery pack, which includes a housing 202 and one or more battery cell assemblies housed in the housing 202.

[0081] As an example, the battery cell assembly can be a battery module 201, which can be housed in a housing 202 by fixing the battery module 201 in the housing.

[0082] As an example, the battery cell assembly can also be housed in the housing 202 by directly fixing multiple battery cells 3 to the housing 202.

[0083] As an example, the housing 202 may include a first housing 2021 and a second housing 2022. The first housing 2021 and the second housing 2022 are fastened together, forming a closed space inside the housing 202 to house the battery cell assembly. Here, "closed" refers to covering or closing, which can be sealed or unsealed. The first housing 2021 may be an end cap or a bottom plate.

[0084] As an example, the housing 202 may include an end cap, a frame, and a base plate. The end cap and the base plate are respectively connected to the frame, so that the interior of the housing 202 forms an enclosed space to accommodate the battery cell assembly.

[0085] In some embodiments, the housing 202 may be part of the vehicle's chassis structure. For example, a portion of the housing 202 may be at least a portion of the vehicle's floor, or a portion of the housing 202 may be at least a portion of the vehicle's crossbeams and longitudinal beams.

[0086] Figure 3 A schematic diagram of the structure of a battery module 201 according to an embodiment of this application is shown.

[0087] In some embodiments, such as Figure 2 and Figure 3 As shown, there are multiple battery cells 3. These multiple battery cells 3 are first connected in series, parallel, or in a mixed manner to form a battery module 201. The multiple battery modules 201 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing 202.

[0088] Multiple battery cells 3 in the battery module 201 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 3 in the battery module 201.

[0089] Figure 4 This is an exploded view of a battery cell according to an embodiment of this application. Battery cell 3 refers to the smallest unit that makes up a battery device. Figure 4 The battery cell 3 includes an end cap assembly 6, a housing 4, and an electrode assembly 5.

[0090] Electrode assembly 5 is the component in the battery cell 3 where the electrochemical reaction occurs. The casing 4 may contain one or more electrode assemblies 5. Electrode assembly 5 is mainly formed by winding or stacking electrode sheets, which are divided into positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the electrode body 52, while the portions of the positive and negative electrode sheets without active material each constitute a tab 51. The positive and negative tabs can be located together at one end of the electrode body 52 or separately at both ends of the electrode body 52. ​​During the charging and discharging process of the battery cell 3, the positive and negative active materials react with the electrolyte, and the tabs 51 connect to the electrode terminals to form a current loop.

[0091] The electrode assembly 5 can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0092] In some embodiments, the electrode assembly 5 is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0093] In some embodiments, the electrode assembly 5 is a stacked structure. As an example, multiple positive and negative electrodes can be provided, with multiple positive and multiple negative electrodes stacked alternately. Multiple spacers can be provided and respectively provided between any adjacent positive or negative electrodes. Alternatively, the spacers can be provided continuously and provided between any adjacent positive or negative electrodes by folding.

[0094] In some embodiments, the electrode assembly 5 may be cylindrical, flat, or polygonal in shape.

[0095] In some embodiments, the electrode assembly 5 is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0096] The battery cell 3 may include a housing. The housing 4 is an assembly used to cooperate with the end cap assembly 6 to form the internal environment of the battery cell 3, wherein the formed internal environment can accommodate the electrode assembly 5, electrolyte (not shown in the figure), and other components. The housing 4 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc. In some embodiments, the housing 4 can be a sealed structure or a non-sealed structure. As an example, when the housing 4 is a non-sealed structure, the housing 4 serves to protect the electrode assembly 5, and a sealing bag is also included between the housing 4 and the electrode assembly 5. The sealing bag is used to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating material or an aluminum-plastic film. When the housing 4 is a sealed structure, it is used to encapsulate the electrode assembly 5 and electrolyte, etc.

[0097] As an example, the battery cell 3 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0098] The housing 4 and the end cap assembly 6 can be independent components. One or more openings can be provided on the housing 4, and one or more end cap assemblies 6 can close the openings to form the internal environment of the battery cell 3. Optionally, the end cap assembly 6 and the housing 4 can also be integrated. Optionally, the end cap assembly 6 and the housing 4 can form a common connection surface before other components are inserted into the housing, and the end cap assembly 6 closes the housing 4 when it is necessary to encapsulate the interior of the housing 4.

[0099] In some embodiments, the electrode terminals can be disposed on the end cap assembly 6 or on the housing 4, and the electrode terminals are electrically connected to the tabs 51. The electrode terminals can be directly connected to the tabs 51 or indirectly connected to the tabs 51 through an adapter mechanism.

[0100] Please see Figure 5 , Figure 6 , Figure 7 and Figure 8 , Figure 5 This is a schematic diagram of the electrode assembly of a battery cell provided in an embodiment of this application; Figure 6 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in an embodiment of this application; Figure 7 yes Figure 6 Sectional view at point AA; Figure 8 This is a partial structural schematic diagram of a battery cell provided in one embodiment of this application.

[0101] Firstly, such as Figures 4 to 8 The present application provides a battery cell 3, which includes a housing 4, an electrode assembly 5, and a heat-conducting assembly 7. The electrode assembly 5 is located inside the housing 4 and includes an electrode body 52 and a tab 51 connected to each other. The electrode body 52 includes a first end face 521 and a second end face 522 disposed opposite to each other in a first direction X, and a side surface 523 connecting the first end face 521 and the second end face 522. The tab 51 extends out of at least one of the first end face 521 and the second end face 522. The heat-conducting assembly 7 includes an insulating member 71 and a heat-conducting member 72. The insulating member 71 forms a receiving cavity 711 in at least a portion of its area. The heat-conducting member 72 is disposed in the receiving cavity 711. Both the insulating member 71 and the heat-conducting member 72 are disposed around the periphery of the electrode body 52. ​​The heat-conducting member 72 is provided with a gap 75, which extends along the first direction X and penetrates the heat-conducting member 72.

[0102] In the embodiment of this application, the battery cell 3 includes a housing 4, an electrode assembly 5, and a heat-conducting assembly 7. The electrode assembly 5 is located inside the housing 4 and includes an electrode body 52 and a tab 51 connected to each other. The electrode body 52 includes a first end face 521, a second end face 522, and a side face 523. The heat-conducting assembly 7 includes an insulating member 71 and a heat-conducting member 72. The insulating member 71 is disposed around the periphery of the electrode body 52, reducing the seams on the insulating member 71 to improve the insulation reliability between the side face 523 and the housing 4. The heat-conducting member 72 is disposed within the receiving cavity 711 of the insulating member 71, so that the heat-conducting member 72 is insulated from the electrode body 52 by the insulating member 71. The heat-conducting element 72 is arranged around the periphery of the electrode body 52 to increase the contact area between the heat-conducting element 72 and the side surface 523 of the electrode body 52, thereby improving the heat exchange rate between the electrode body 52 and the external environment at its side surface 523. The heat-conducting element 72 is provided with a gap 75 extending through the first direction X. By providing the gap 75, the elastic deformation capability of the heat-conducting element 72 is enhanced, so that the heat-conducting element 72 can deform synchronously with the electrode assembly 5, reducing the extrusion pressure between the heat-conducting element 72 and the electrode body 52, reducing the risk of mutual extrusion damage between the heat-conducting element 72 and the electrode body 52, improving the service life of the heat-conducting assembly 7, and improving the reliability of the battery cell 3.

[0103] The electrode body 52 is formed by winding or stacking a diaphragm, a positive electrode plate, and a negative electrode plate. The electrode tab 51 includes a positive electrode tab and a negative electrode tab, both of which extend from the first end face 521 or the second end face 522, or one of the positive electrode tab and the negative electrode tab extends from the first end face 521 and the other extends from the second end face 522.

[0104] For example, the first direction X is the height direction of the electrode assembly 5.

[0105] For example, the insulating component 71 can be PP or PI (polyimide) or PET (polyethylene terephthalate), etc. The thermally conductive component 72 can be made of graphite, graphene, or carbon nanotubes.

[0106] Optionally, the thermal conductivity of the heat-conducting component 7 is greater than that of the housing 4. Specifically, the thermal conductivity of the heat-conducting element 72 is greater than that of the housing 4. After the heat-conducting element 72 is housed within the insulating element 71, the overall thermal conductivity of the heat-conducting component 7 is still greater than that of the housing 4.

[0107] For example, the heat-conducting element 72 is obtained by PI film graphitization technology, and the thermal conductivity of the heat-conducting element 72 is greater than or equal to 1800 W / (m·K). The heat-conducting element 72 is housed in the insulating element 71, and the thermal conductivity of the heat-conducting component 7 is between 1300 W / (m·K) and 1500 W / (m·K).

[0108] Optionally, the heat-conducting component 7 can be wound around one or more electrode components 5. Specifically, the insulating member 71 is connected end to end or the end and middle region of the insulating member 71 are connected to form a hollow structure. The insulating member 71 is a continuous structure in the circumferential direction of the electrode body 52. ​​The insulating member 71 of one heat-conducting component 7 can form one or two hollow structures. One or more electrode components 5 can be disposed in each hollow structure. The heat-conducting member 72 is disposed in the insulating member 71 and can extend continuously in one or two hollow structures.

[0109] Optionally, the heat-conducting element 72 may be plate-shaped, strip-shaped, or mesh-shaped. For example, the receiving cavity 711 is provided with a plate-shaped heat-conducting element, a mesh-shaped heat-conducting element, or one or more spaced strip-shaped heat-conducting elements.

[0110] Optionally, the heat-conducting element 72 disposed on the side 523 of the electrode body 52 can transfer heat in the first direction X to equalize the temperature of the electrode assembly 5 in the first direction X and reduce the temperature difference of the electrode assembly 5 in the first direction X.

[0111] The heat-conducting component 7 is arranged around the periphery of the electrode body 52. ​​The deformation capacity of the insulating component 71 is better than that of the heat-conducting component 72, that is, the elastic modulus of the insulating component 71 is less than that of the heat-conducting component 72. Therefore, a gap 75 is provided in the heat-conducting component 72, extending along the first direction X and penetrating through it. During the expansion of the electrode assembly 5, the size of the gap 75 increases, and during the contraction of the electrode assembly 5, the size of the gap 75 decreases. By setting the gap 75, the elastic deformation capacity of the heat-conducting component 72 can be enhanced, the compressive force of the electrode assembly 5 on the heat-conducting component 72 can be reduced, and the binding force of the heat-conducting component 72 on the electrode assembly 5 can be reduced.

[0112] For example, the two ends of the heat-conducting element 72 are spaced apart to form the gap 75, or the ends and the middle region of the heat-conducting element 72 are spaced apart to form the gap 75. The specific size and shape of the gap 75 can be designed by the user.

[0113] Optionally, the gap 75 extends along the extension direction of the heat conductor 72 and the first direction X to improve the problem that when the two ends of the heat conductor 72 coincide in their thickness direction, the heat conductor 72 is subjected to excessive extrusion pressure during the expansion of the electrode assembly 5, which leads to a decrease in the deformation capacity of the heat conductor 72.

[0114] Optionally, the heat-conducting component 7 is strip-shaped, and in its extending direction, the size of the insulating member 71 is larger than the size of the heat-conducting member 72, so that when the heat-conducting component 7 is wrapped around the side 523 of the electrode body 52, the insulating member 71 can form a closed ring along the circumferential direction of the electrode body 52, while the heat-conducting member 72 can form a gap 75.

[0115] Optionally, the insulating member 71 is provided with a receiving cavity 711 with one end open, and the heat-conducting member 72 is disposed in the receiving cavity 711 and bonded or fused to the opening of the insulating member 71, so that the heat-conducting member 72 is located in a sealed receiving cavity 711; or the two ends of the insulating member 71 are folded in half, the heat-conducting member 72 is located between the two ends of the insulating member 71, and the two ends of the insulating member 71 are bonded or fused together, so that the heat-conducting member 72 is located in a sealed receiving cavity 711; or the insulating member 71 includes two sub-insulating layers 712 disposed opposite to each other, and the edges of the two sub-insulating layers 712 are bonded or fused together, so that the heat-conducting member 72 is located in a sealed receiving cavity 711.

[0116] For example, the insulating component 71 includes two sub-insulating layers 712, which are stacked together. The outer surface of the heat-conducting component 72 is provided with an adhesive layer. The heat-conducting component 72 is disposed between the two sub-insulating layers 712. The sub-insulating layers 712 and the heat-conducting component 72 are bonded together. Then, a preset temperature is applied to the sub-insulating layers 712, and the heat-conducting component 72 and the sub-insulating layers 712 are thermoplasticized together. Then, the edges of the two sub-insulating layers 712 are bonded or fused together. This can improve the stability of the heat-conducting component 72 in the receiving cavity 711 and reduce the risk of air bubbles between the heat-conducting component 72 and the insulating component 71 affecting the heat conduction of the heat-conducting component 7.

[0117] Optionally, the insulating element 71 covers the entire side 523 to improve the insulation reliability of the electrode assembly 5 and the housing 4.

[0118] Optionally, the gap 75 extends along a straight line in the first direction X to reduce the size of the gap 75.

[0119] Optionally, the gap 75 can be set at the first side 5231. During the expansion of the electrode assembly 5, the expansion amplitude at the first side 5231 is greater. Therefore, setting the gap 75 at the first side 5231 makes it easier for the heat-conducting component 72 to absorb the expansion of the electrode assembly 5 through the gap 75, further reducing the risk of the heat-conducting component 72 being damaged by the electrode body 52, improving the service life of the heat-conducting component 7, and improving the reliability of the battery cell 3.

[0120] Optionally, the insulating component 71 includes two sub-insulating layers 712, which are stacked and interconnected to form a receiving cavity 711. The thickness D1 of the sub-insulating layer 712 satisfies the condition 0.02mm≤D1≤0.04mm. Meeting this condition can mitigate the problem of excessively thick sub-insulating layers 712 leading to excessively large battery cell volume and reduced energy density, while also addressing the issue of easily damaged sub-insulating layers 712 due to excessively thin sub-insulating layers 712.

[0121] For example, the thickness of the sub-insulating layer 712 can be 0.02 mm, 0.03 mm, 0.04 mm, etc.

[0122] Optionally, the thickness D2 of the heat-conducting component 72 satisfies 0.08mm≤D2≤0.2mm. Meeting the above condition can both improve the problem of excessively thick heat-conducting component 72 leading to excessively large volume of battery cell 3 and reduced energy density, and also improve the problem of heat-conducting component 72 being easily damaged due to excessively thin heat-conducting component 72.

[0123] For example, the thickness of the heat-conducting element 72 can be 0.08mm, 0.1mm, 0.15mm, 0.2mm, etc.

[0124] Please see Figure 9 , Figure 9 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application.

[0125] In some embodiments, such as Figure 5 , Figure 8 and Figure 9 As shown, side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232. The two first side surfaces 5231 are arranged opposite each other in the second direction Y, and the two second side surfaces 5232 are arranged opposite 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. At least part of the orthographic projection of the gap 75 on the electrode assembly 5 is located on the second side surface 5232.

[0126] In these embodiments, the gap 75 is projected at least partially onto the second side 5232 of the electrode assembly 5 to reduce the extrusion pressure on the end of the heat conductor 72 and the electrode assembly 5 during the expansion of the electrode assembly 5, thereby improving the problem of stress concentration at the end of the heat conductor 72 during the expansion of the electrode assembly 5, which leads to uneven ion distribution and increased risk of lithium plating, and improving the reliability of the battery cell 3.

[0127] Optionally, the second direction Y is the thickness direction of the electrode assembly 5, and the first side surface 5231 is the large surface of the electrode assembly 5. The first direction X is the height direction of the electrode assembly 5, and the third direction Z is the length direction of the electrode assembly 5.

[0128] The electrode body 52 includes a first side 5231 and a second side 5232 with different areas. For example, the cross-section of the electrode body 52 in the first direction X is rectangular or elliptical, etc.

[0129] During the expansion of the electrode assembly 5, the expansion amplitude is large at the first side 5231. If the gap 75 is located at the first side 5231, stress concentration will occur at the end of the heat-conducting component 72 at the first side 5231, resulting in uneven lithium ion distribution and increased risk of lithium plating. Therefore, in this embodiment, the gap 75 is located at the second side 5232, where the expansion amplitude is relatively smaller.

[0130] Optionally, part of the orthographic projection of the gap 75 onto the electrode assembly 5 is located on the first side 5231, and the other part is located on the second side 5232, in order to reduce the difficulty of setting up the heat-conducting component 72; or the orthographic projection of the gap 75 onto the electrode assembly 5 is located on the second side 5232, further reducing the risk of lithium plating.

[0131] In some embodiments, such as Figure 4 , Figure 6 , Figure 8 and Figure 9 As shown, the heat-conducting element 72 is wound around at least one electrode body 52, and a gap 75 is formed between the two ends of the heat-conducting element 72.

[0132] In these embodiments, the heat-conducting element 72 is wrapped around at least one electrode body 52 to increase the contact area between the heat-conducting element 72 and the side surface 523 of the electrode body 52, thereby increasing the heat exchange rate between the electrode body 52 and the external environment at its side surface 523. A gap 75 is formed between the two ends of the heat-conducting element 72 to reduce the processing difficulty of the heat-conducting component 7.

[0133] Specifically, the insulating component 71 is connected end to end to surround the electrode body 52, the heat-conducting component 72 is housed within the insulating component 71 and is wound around the electrode body 52, and a gap 75 is formed between the two ends of the heat-conducting component 72. The two ends of the insulating component 71 are connected by means of bonding or welding.

[0134] For example, the heat-conducting element 72 is wound around one or more electrode bodies 52.

[0135] Optionally, the heat-conducting element 72 may include only one gap 75 to give the heat-conducting element 72 good thermal conductivity.

[0136] Please see Figure 10 , Figure 10 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in an embodiment of this application.

[0137] In some embodiments, such as Figure 5 , Figures 8 to 10 As shown, the heat-conducting component 72 includes a first heat-conducting part 721, a second heat-conducting part 722, and a third heat-conducting part 723. The two first heat-conducting parts 721 are respectively disposed on two first side surfaces 5231, and the second heat-conducting parts 722 and the third heat-conducting parts 723 are respectively disposed on two second side surfaces 5232. The second heat-conducting part 722 is connected to the two first heat-conducting parts 721. The third heat-conducting part 723 is connected to one first heat-conducting part 721 and is spaced apart from the other first heat-conducting part 721 to form a gap 75. Alternatively, the two third heat-conducting parts 723 are respectively connected to the two first heat-conducting parts 721, and the two third heat-conducting parts 723 are spaced apart in the second direction Y to form a gap 75.

[0138] In these embodiments, the third heat-conducting part 723 is connected to a first heat-conducting part 721 and is spaced apart from another first heat-conducting part 721 to form a gap 75. The third heat-conducting part 723 is disposed on the second side surface 5232, which helps to increase the contact area between the heat-conducting component 72 and the side surface 523, improve the heat conduction efficiency of the heat-conducting component 72, and absorb some of the fitting error between the heat-conducting component 7 and the electrode component 5 through the third heat-conducting part 723, thereby reducing the difficulty of setting the heat-conducting component 7.

[0139] The first heat-conducting part 721 is disposed on the first side surface 5231, which means that the orthographic projection of the first heat-conducting part 721 in its thickness direction is on the first side surface 5231. The same applies to the second heat-conducting part 722 and the third heat-conducting part 723.

[0140] Two first heat-conducting parts 721 are respectively disposed on two first side surfaces 5231, and one or more electrode bodies 52 are spaced between the two first heat-conducting parts 721.

[0141] The first heat-conducting part 721 is disposed on the first side surface 5231, so the first heat-conducting part 721 can conduct heat from the first side surface 5231. The second heat-conducting part 722 is connected to the same end of the two first heat-conducting parts 721 in the third direction Z. The second heat-conducting part 722 is used to conduct heat from the second side surface 5232 and to transfer heat between the two first heat-conducting parts 721.

[0142] Optionally, the first heat-conducting part 721, the second heat-conducting part 722 and the third heat-conducting part 723 are integrally formed to improve the heat conduction efficiency of the heat-conducting component 72.

[0143] Optionally, the third heat-conducting part 723 is connected to the first heat-conducting part 721 and bent and disposed on the second side 5232, so that the first heat-conducting part 721 extends sufficiently along the third direction Z on the first side 5231, thereby enhancing the heat conduction rate of the first heat-conducting part 721.

[0144] Two first heat-conducting parts 721 are respectively the first component and the second component. The third heat-conducting part 723 and the second heat-conducting part 722 are respectively disposed at both ends of the first component in the third direction Z. The third heat-conducting part 723 extends toward the second component in the second direction Y. The heat-conducting parts and the second component are spaced apart, and a gap 75 is formed between the third heat-conducting part 723 and the second component, so that the distance between the third heat-conducting part 723 and the second component is adjustable, thereby enhancing the overall deformation capability of the heat-conducting component 72.

[0145] Optionally, the two third heat-conducting parts 723 are disposed on the two first heat-conducting parts 721, and the two third heat-conducting parts 723 have the same or different extension dimensions in the second direction Y.

[0146] Please see Figure 11 and Figure 12 , Figure 11 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application; Figure 12 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application.

[0147] In some embodiments, such as Figure 11 and Figure 12 As shown, at least two electrode assemblies 5 are provided, and the at least two electrode assemblies 5 are stacked along the second direction Y. The heat-conducting element 72 extends continuously and forms two heat-conducting structures 724 arranged along the second direction Y. The heat-conducting structures 724 are wrapped around at least one electrode body 52. ​​At least one end and the middle region of the heat-conducting element 72 are spaced apart to form a gap 75.

[0148] In these embodiments, the heat-conducting element 72 extends continuously and forms two heat-conducting structures 724 arranged along the second direction Y. The heat-conducting structures 724 are wrapped around at least one electrode body 52 so that a single heat-conducting component 7 can provide insulation and heat conduction for more electrode bodies 52. This helps to reduce the overall size of the heat-conducting component 7 and save the material cost of the battery cell 3. The ends and middle regions of at least one heat-conducting element 72 are spaced apart to form a gap 75 to reduce the risk of mutual compression damage between the heat-conducting element 72 and the electrode assembly 5.

[0149] Specifically, the heat-conducting element 72 extends continuously and forms two heat-conducting structures 724 arranged along the second direction Y. The heat-conducting element 72 is housed within the insulating element 71. Both ends of the insulating element 71 are connected to the two side surfaces of its central region. For example, the insulating element 71 is figure-eight shaped. The heat-conducting structures 724 are wrapped around at least one electrode body 52. ​​A gap 75 is disposed at at least one heat-conducting structure 724, that is, at least one of the ends of the heat-conducting element 72 is spaced apart from its central region to form a gap 75. The central region of the heat-conducting element 72 refers to the portion between the two ends of the heat-conducting element 72.

[0150] Optionally, the two gaps 75 are respectively located in the two heat-conducting structures 724, and the two ends of the heat-conducting component 72 are spaced apart from the middle area of ​​the heat-conducting component 72, so as to reduce the risk of mutual compression and damage between the heat-conducting component 72 and the electrode assembly 5.

[0151] Please see Figure 13 , Figure 13 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application.

[0152] In some embodiments, such as Figure 5 , Figures 11 to 13As shown, the heat-conducting component 72 includes a first heat-conducting part 721, two second heat-conducting parts 722, and two third heat-conducting parts 723. The first heat-conducting part 721 includes a middle heat-conducting component 7211 and two end heat-conducting components 7212. The middle heat-conducting component 7211 is disposed between the two end heat-conducting components 7212 along the second direction Y. The end heat-conducting components 7212 and the middle heat-conducting component 7211 are respectively disposed on both sides of the electrode assembly 5. The middle heat-conducting component 7211 is disposed on two adjacent first side surfaces 523 of two adjacent electrode assemblies 5. Between 1, the second heat-conducting part 722 and the third heat-conducting part 723 are respectively disposed at both ends of the same end heat-conducting member 7212 in the third direction Z. The two second heat-conducting parts 722 are respectively connected to both ends of the middle heat-conducting member 7211 in the third direction Z. The third heat-conducting part 723 and the middle heat-conducting member 7211 are spaced apart to form a gap 75. The end heat-conducting member 7212 and the second heat-conducting part 722 and the third heat-conducting part 723 connected thereto, as well as the middle heat-conducting member 7211, form the same heat-conducting structure 724.

[0153] In these embodiments, the central heat conductor 7211 is disposed between two adjacent first sides 5231 of two adjacent electrode assemblies 5, so that the heat between adjacent battery cells 3 can be transferred to the outside through the central heat conductor 7211 and the second heat conductor 722, which helps to equalize the temperature of the battery cells 3. The second heat conductor 722, the end heat conductor 7212 and the third heat conductor 723 are respectively arranged around the electrode assembly 5 in cooperation with the central heat conductor 7211. By sharing the central heat conductor 7211, the overall size of the heat conductor assembly 7 is reduced, saving the material cost of the battery cells 3.

[0154] Specifically, the heat-conducting component 72 includes a first heat-conducting part 721, two second heat-conducting parts 722 and two third heat-conducting parts 723. The first heat-conducting part 721 includes a middle heat-conducting component 7211 and two end heat-conducting components 7212. The middle heat-conducting component 7211, a second heat-conducting part 722 connected to the middle heat-conducting component 7211, and the third heat-conducting part 723 and the end heat-conducting components 7212 connected to the second heat-conducting part 722 and disposed on the same side of the middle heat-conducting component 7211 in the second direction Y form the same heat-conducting structure 724.

[0155] For example, compared to the case where the two heat-conducting components 7 are respectively wound around the two electrode bodies 52, when the two heat-conducting structures 724 of the heat-conducting component 72 are respectively wound around the two electrode bodies 52, the overall material cost of the heat-conducting component 7 can be reduced because the central heat-conducting component 7211 is shared.

[0156] Optionally, the spacing between the central heat-conducting element 7211 and the two third heat-conducting parts 723 in the second direction Y may be the same or different. For example, the spacing between the central heat-conducting element 7211 and the two third heat-conducting parts 723 in the second direction Y is the same to evenly set the temperature of the two second sides 5232 of the third heat-conducting parts 723.

[0157] Please see Figure 14 , Figure 14 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application.

[0158] In some embodiments, such as Figure 14 As shown, multiple electrode assemblies 5 are provided, and the multiple electrode assemblies 5 are stacked along the second direction Y. The battery cell 3 includes at least two heat-conducting components 7 that are spaced apart along the second direction Y. The at least two heat-conducting components 7 are respectively disposed on at least two electrode assemblies 5.

[0159] In these embodiments, multiple electrode assemblies 5 are stacked along the second direction Y to increase the capacity of the battery cell 3, and at least two heat-conducting components 7 are respectively wound around at least two electrode assemblies 5 to reduce the difficulty of matching the heat-conducting components 7 and the electrode assemblies 5.

[0160] The battery cell 3 is provided with a plurality of electrode assemblies 5 stacked along the second direction Y, and at least two heat-conducting assemblies 7. The at least two heat-conducting assemblies 7 are spaced apart along the second direction Y and are respectively wound around different electrode assemblies 5. For example, the battery cell 3 is provided with 1, 2, 3, 4, etc., electrode assemblies 5.

[0161] Optionally, the two first heat-conducting parts 721 of two adjacent heat-conducting components 7 are respectively disposed between two adjacent electrode components 5 along the second direction Y, or the two adjacent heat-conducting components 7 are respectively disposed on both sides of one or more electrode components 5 along the second direction Y.

[0162] Optionally, the heat-conducting component 7 with gap 75 formed between the two ends of the heat-conducting component 72 is a first structure, and the heat-conducting component 7 with gap 75 formed between the end and middle regions of the heat-conducting component 72 is a second structure. Multiple electrode components 5 are stacked along the second direction Y to form an electrode component 5. The first structure and the second structure can be disposed in the same electrode component 5 along the second direction Y.

[0163] Optionally, between two adjacent first sides 5231 of two adjacent electrode assemblies 5, two independent heat-conducting components 7 are provided with two first heat-conducting parts 721. These two first heat-conducting parts 721 abut against each other along the third direction Z, or the two first heat-conducting parts 721 are spaced apart along the third direction Z. This helps to reduce the size of the heat-conducting component 72, improve the heat conduction efficiency of the electrode assembly 5, reduce the processing cost of the battery cell 3, and also helps to reduce the overall size of the heat-conducting component 72 in the second direction Y, thereby increasing the energy density of the battery cell 3.

[0164] In some embodiments, such as Figure 14 As shown, at least two gaps 75 are respectively located on both sides of the electrode assembly 5 in the third direction Z.

[0165] In these embodiments, at least two gaps 75 are respectively disposed on both sides of the electrode assembly 5 in the third direction Z, so as to balance the restraining force on the multiple electrode assemblies 5 arranged along the second direction Y at both ends of the third direction Z, and to balance the degree of deformation of the multiple electrode assemblies 5 at both ends of the third direction Z.

[0166] Specifically, the gap 75 is set on one side of the heat-conducting component 7 in the third direction Z. After the heat-conducting component 7 is wrapped around the electrode component 5, there is a difference in the binding force of the heat-conducting component 7 on the electrode component 5 at both ends in the third direction Z. The electrode component 5 is subjected to a smaller binding force at the end where the gap 75 is set, and the degree of expansion of the electrode component 5 at the end closer to the gap 75 in the third direction Z will be greater than that at the other end.

[0167] Several electrode components 5 are stacked in the housing 4 along the second direction Y. If the gaps 75 are distributed on one side of the electrode components 5 in the third direction Z, the housing 4 will have a large deformation difference on both sides of the second direction Y during the expansion of the electrode components 5. Therefore, in this embodiment, several gaps 75 are distributed on both sides of the electrode components 5 in the third direction Z to balance the deformation difference of the housing 4 in the third direction Z.

[0168] Optionally, two adjacent gaps 75 are respectively located on both sides of the electrode assembly 5 in the third direction Z, so as to better balance the deformation of the stacked electrode assembly 5.

[0169] Please see Figure 15 , Figure 15 This is a partial structural schematic diagram of a battery cell provided in another embodiment of this application.

[0170] In some embodiments, such as Figure 4 , Figure 6 , Figure 15As shown, side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232. The two first side surfaces 5231 are arranged opposite each other in the second direction Y, and the two second side surfaces 5232 are arranged opposite each other in the third direction Z. The first direction X, the second direction Y and the third direction Z intersect each other. The heat-conducting component 7 also includes an adhesive layer 74. The insulating component 71 is bonded to the first side surface 5231 through the adhesive layer 74. The adhesive layer 74 is spaced apart at the edges of the third direction Z and the first side surface 5231.

[0171] In these embodiments, the adhesive layer 74 is spaced apart at the edges of the third direction Z and the first side surface 5231, so that the insulating member 71 forms a deformation space between the adhesive layer 74 and the edges of the first side surface 5231, so as to facilitate the thermal conductive component 7 to deform together with the electrode component 5 during the expansion of the battery cell 3, and reduce the risk of mutual compression and damage between the electrode component 5 and the thermal conductive component 7 during the expansion process.

[0172] Optionally, the adhesive layer 74 can be applied with dispensing or double-sided adhesive, etc.

[0173] Part of the thermal conductive component 7 is bonded to the side 523 by the adhesive layer 74. However, part of the thermal conductive component 7 located in the area between the adhesive layer 74 in the third direction Z and the edge of the first side 5231 is not fixed. This allows the unfixed part of the thermal conductive component 7 to easily deform in the second direction Y during the expansion of the battery cell 3. This deformation absorbs the expansion of the electrode assembly 5 and reduces the risk of the thermal conductive component 7 bursting.

[0174] Optionally, the first side 5231 and the second side 5232 are connected by rounded corners, and the adhesive layer 74 and the rounded corner area are spaced apart. This makes it easier for the second heat-conducting part 722 corresponding to the rounded corner area to deform, and also reduces the difficulty of setting the adhesive layer 74.

[0175] Optionally, multiple adhesive layers 74 are respectively disposed at the ends of the first sidewall 5231 in the first direction X and the third direction Z. When the adhesive layers 74 can fix the heat-conducting component 7 and the first sidewall, a gap 75 for accommodating the expansion of the electrode component 5 can be formed between the middle region of the first sidewall and the heat-conducting component 7, thereby reducing the material cost of the battery cell 3. For example, four rectangular adhesive layers 74 are adjacent to each other and are respectively disposed at the edges of the first sidewall in the first direction X and the third direction Z.

[0176] Optionally, the minimum spacing between the adhesive layer 74 along the third direction Z and the edge of the first side surface 5231 is greater than or equal to 10 mm. Meeting this requirement facilitates the deformation of the heat-conducting component 7 along with the electrode component 5 during expansion, mitigating the risk of damage from mutual compression between the electrode component 5 and the heat-conducting component 7 during expansion. It also reduces the size of the adhesive layer 74, lowering the processing cost of the battery cell 3. For example, the minimum spacing between the adhesive layer 74 along the third direction Z and the edge of the first side surface 5231 can be 10 mm, 11 mm, 12 mm, etc.

[0177] Please see Figure 16 and Figure 17 , Figure 16 This is an exploded view of a single battery cell provided in another embodiment of this application; Figure 17 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application.

[0178] In some embodiments, such as Figure 6 , Figure 16 and Figure 17 As shown, the housing 4 includes an opening in the first direction X, the battery cell 3 also includes an end cap assembly 6, the end cap assembly 6 covers the opening and is connected to the tab 51, and at least a portion of the insulating member 71 extends out of the first end face 521 in the first direction X and is connected to the end cap assembly 6.

[0179] In these embodiments, at least a portion of the insulating member 71 extends out of the first end face 521 in the first direction X and is connected to the end cap assembly 6, so that the end cap assembly 6 plays a role in positioning and fixing the heat-conducting component 7, thereby improving the stability of the heat-conducting component 7 within the housing 4.

[0180] At least part of the insulating component 71 extends out of the first end face 521 and is fused to the lower plastic of the end cap assembly 6. The heat-conducting component 72 and the side 523 are thermally connected. The heat-conducting component 72 does not extend beyond the first end face 521. This can reduce the risk of damage to the heat-conducting component 72 and reduce the material cost of the heat-conducting assembly 7.

[0181] Optionally, the dimension L of the insulating member 71 extending beyond the first end face 521 in the first direction X is between 5mm and 10mm. When the above condition is met, the connection reliability between the heat-conducting assembly 7 and the end cap assembly 6 is improved. For example, the dimension L of the insulating member 71 extending beyond the first end face 521 in the first direction X is 5mm, 7.5mm, 8mm, or 10mm, etc.

[0182] Please see Figure 18 , Figure 18 This is a schematic diagram of the structure of the heat-conducting component of a battery cell provided in another embodiment of this application.

[0183] In some embodiments, such as Figure 4 and Figure 18 As shown, the tab 51 extends out of the first end face 521, and the battery cell 3 also includes an insulation mechanism 8, which is disposed on the second end face 522 and connected to the insulation member 71.

[0184] In these embodiments, the insulating mechanism 8 disposed on the second end face 522 helps to enhance the insulation performance of the second end face 522 and the housing 4. The insulating member 71 and the insulating mechanism 8 are connected to make the heat-conducting assembly 7 more reliably insulate the electrode assembly 5 and the housing 4.

[0185] Optionally, the insulating component 71 and the insulating mechanism 8 are manufactured separately, with the insulating component 71 and the insulating mechanism 8 being independent of each other, and the insulating component 71 and the insulating mechanism 8 being connected by abutment, so as to reduce the processing difficulty of the heat-conducting component 7.

[0186] Optionally, the insulating element 71 and the insulating mechanism 8 may be bonded or fused together to improve the stability of the thermally conductive assembly.

[0187] Optionally, a rounded corner is provided at the corner of the end of the housing 4 near the second end face 522. The thickness of the insulating mechanism 8 is greater than or equal to the size of the rounded corner in the first direction X. The rounded corner of the electrode assembly 5 and the housing 4 is separated by the insulating mechanism 8, thereby improving the interference problem between the electrode assembly 5 and the rounded corner.

[0188] Optionally, the thickness of the insulating mechanism 8 is greater than or equal to 2 mm. For example, the thickness of the insulating mechanism 8 is 2 mm, 2.1 mm, 2.5 mm, etc. For example, the material of the insulating mechanism 8 is PP or PET, etc.

[0189] Optionally, the insulating mechanism 8 is provided with a capillary structure so that the electrolyte can wet the electrode assembly 5 through the insulating mechanism 8.

[0190] Secondly, embodiments of this application provide a battery device including a battery cell from any of the embodiments of the first aspect described above.

[0191] Thirdly, embodiments of this application provide an electrical device, including the battery device described in the second aspect of the embodiment above.

[0192] In some embodiments, such as Figures 1 to 18As shown, the battery cell 3 includes a housing 4, an electrode assembly 5, and a heat-conducting assembly 7. The electrode assembly 5 is located inside the housing 4 and includes an electrode body 52 and a tab 51 connected to each other. The electrode body 52 includes a first end face 521 and a second end face 522 disposed opposite to each other in a first direction X, and a side surface 523 connecting the first end face 521 and the second end face 522. The tab 51 extends out of the first end face 521. The side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232. The two first side surfaces 5231 are disposed opposite to each other in a second direction Y, and the two second side surfaces 5232 are disposed opposite to each other in a third direction Z. The components are arranged opposite each other, with the area of ​​the first side 5231 being larger than the area of ​​the second side 5232; the thermal conductivity of the heat-conducting component 7 is greater than that of the housing 4. The heat-conducting component 7 includes an insulating member 71, an insulating mechanism 8, an adhesive layer 74, and a heat-conducting member 72. At least a portion of the insulating member 71 forms a receiving cavity 711, and the heat-conducting member 72 is disposed within the receiving cavity 711. Both the insulating member 71 and the heat-conducting member 72 are arranged around the periphery of the electrode body 52. ​​The heat-conducting member 72 is provided with a gap 75, which extends along the first direction X and penetrates the heat-conducting member 72. At least a portion of the orthographic projection of the gap 75 onto the electrode assembly 5 is located on the second side 5232. 2. At least one electrode body 52 is wound around the heat-conducting element 72, and a gap 75 is formed between the two ends of the heat-conducting element 72. Alternatively, at least two electrode assemblies 5 are provided, and at least two electrode assemblies 5 are stacked along the second direction Y. The heat-conducting element 72 extends continuously and forms two heat-conducting structures 724 arranged along the second direction Y. The heat-conducting structures 724 are wound around at least one electrode body 52. ​​The ends and middle regions of at least one heat-conducting element 72 are spaced apart to form a gap 75. Multiple electrode assemblies 5 are provided, and multiple electrode assemblies 5 are stacked along the second direction Y. The battery cell 3 includes at least two heat-conducting components 7 spaced apart along the second direction Y. At least two heat-conducting components 7 are disposed on at least two electrode components 5, and at least two gaps 75 are disposed on both sides of the electrode components 5 in the third direction Z. The side surface 523 includes two first side surfaces 5231 and two second side surfaces 5232. The two first side surfaces 5231 are disposed opposite each other in the second direction Y, and the two second side surfaces 5232 are disposed opposite each other in the third direction Z. The first direction X, the second direction Y and the third direction Z intersect each other. The heat-conducting component 7 also includes an adhesive layer 74. The insulating component 71 is bonded to the first side surface 5231 through the adhesive layer 74. The adhesive layer 74 is spaced apart at the edges of the third direction Z and the first side surface 5231.

[0193] In these embodiments, the battery cell 3 includes a housing 4, an electrode assembly 5, and a heat-conducting assembly 7. The electrode assembly 5 is located within the housing 4 and includes an electrode body 52 and a tab 51 connected to each other. The electrode body 52 includes a first end face 521, a second end face 522, and a side face 523. The heat-conducting assembly 7 includes an insulating member 71 and a heat-conducting member 72. The insulating member 71 is disposed around the periphery of the electrode body 52, reducing the seams on the insulating member 71 to improve the insulation reliability between the side face 523 and the housing 4. The heat-conducting member 72 is disposed within the receiving cavity 711 of the insulating member 71, so that the heat-conducting member 72 is insulated from the electrode body 52 by the insulating member 71. The heat-conducting element 72 is arranged around the periphery of the electrode body 52 to increase the contact area between the heat-conducting element 72 and the side surface 523 of the electrode body 52, thereby improving the heat exchange rate between the electrode body 52 and the external environment at its side surface 523. The heat-conducting element 72 is provided with a gap 75 extending through the first direction X. By providing the gap 75, the elastic deformation capability of the heat-conducting element 72 is enhanced, so that the heat-conducting element 72 can deform synchronously with the electrode assembly 5, reducing the extrusion pressure between the heat-conducting element 72 and the electrode body 52, reducing the risk of mutual extrusion damage between the heat-conducting element 72 and the electrode body 52, improving the service life of the heat-conducting assembly 7, and improving the reliability of the battery cell 3.

[0194] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: case; An electrode assembly is located inside the housing. The electrode assembly includes an electrode body and a tab connected to each other. The electrode body includes a first end face and a second end face disposed 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 extends out of at least one of the first end face and the second end face. A heat-conducting component includes an insulating element and a heat-conducting element. At least a portion of the insulating element forms a receiving cavity. The heat-conducting element is disposed within the receiving cavity. Both the insulating element and the heat-conducting element are disposed around the periphery of the electrode body. The heat-conducting element has a gap that extends along the first direction and penetrates the heat-conducting element.

2. The battery cell according to claim 1, characterized in that, The side surface includes two first side surfaces and two second side surfaces. The two first side surfaces are arranged opposite each other in a second direction, and the two second side surfaces are arranged opposite each other in a 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. The gap is at least partially projected onto the second side of the electrode assembly.

3. The battery cell according to claim 2, characterized in that, The heat-conducting element is wound around at least one of the electrode bodies, and the gap is formed between the two ends of the heat-conducting element.

4. The battery cell according to claim 3, characterized in that, The heat-conducting component includes a first heat-conducting part, a second heat-conducting part, and a third heat-conducting part. Two first heat-conducting parts are disposed on two first side surfaces, and the second and third heat-conducting parts are disposed on two second side surfaces. The second heat-conducting part is connected to the two first heat-conducting parts. The third heat-conducting part is connected to one of the first heat-conducting parts and is spaced apart from another of the first heat-conducting parts to form the gap, or the two third heat-conducting parts are respectively connected to the two first heat-conducting parts and are spaced apart in the second direction to form the gap.

5. The battery cell according to claim 2, characterized in that, The electrode assembly is provided in at least two forms, and the at least two electrode assemblies are stacked along the second direction. The heat-conducting element extends continuously and forms two heat-conducting structures arranged along the second direction. The heat-conducting structures are wrapped around at least one of the electrode bodies. At least one end and a middle region of the heat-conducting element are spaced apart to form the gap.

6. The battery cell according to claim 5, characterized in that, The heat-conducting component includes a first heat-conducting portion, two second heat-conducting portions, and two third heat-conducting portions. The first heat-conducting portion includes a central heat-conducting component and two end heat-conducting components. The central heat-conducting component is disposed between the two end heat-conducting components along the second direction. The end heat-conducting components and the central heat-conducting component are respectively disposed on both sides of the electrode assembly. The central heat-conducting element is disposed between two adjacent first sides of two adjacent electrode assemblies. The second heat-conducting part and the third heat-conducting part are disposed at both ends of the same end heat-conducting element in the third direction. The two second heat-conducting parts are respectively connected to the two ends of the central heat-conducting element in the third direction. The third heat-conducting part and the central heat-conducting element are spaced apart to form the gap. The end heat-conducting element and the second heat-conducting part and the third heat-conducting part connected thereto, as well as the central heat-conducting element, form the same heat-conducting structure.

7. The battery cell according to any one of claims 2-6, characterized in that, Multiple electrode assemblies are provided, and the multiple electrode assemblies are stacked along the second direction. The battery cell includes at least two heat-conducting components spaced apart along the second direction, and the at least two heat-conducting components are disposed on at least two electrode components.

8. The battery cell according to claim 7, characterized in that, At least two of the gaps are located on either side of the electrode assembly in a third direction.

9. The battery cell according to claim 1, characterized in that, The side surface includes two first side surfaces and two second side surfaces. The two first side surfaces are arranged opposite each other in a second direction, and the two second side surfaces are arranged opposite each other in a third direction. The first direction, the second direction, and the third direction intersect each other. The thermally conductive component further includes an adhesive layer, through which the insulating element is bonded to the first side surface, and the adhesive layer is spaced apart at the edges of the third direction and the first side surface.

10. The battery cell according to claim 1, characterized in that, The housing includes an opening in the first direction, and the battery cell further includes an end cap assembly that covers the opening and is connected to the tab. At least a portion of the insulating member extends from the first end face in the first direction and is connected to the end cap assembly.

11. The battery cell according to claim 1, characterized in that, The tab extends from the first end face, and the battery cell also includes an insulation mechanism disposed on the second end face and connected to the insulation component.

12. A battery device, characterized in that, Includes the battery cell described in any one of claims 1-11 above.

13. An electrical appliance, characterized in that, Includes the battery device described in claim 12 above.

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