Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device. The battery cell comprises: a housing provided with a pressure relief mechanism; the electrode assembly is positioned in the shell; the heat conduction assembly comprises a first heat conduction part, the first heat conduction part is in heat conduction connection with the electrode assembly, the first heat conduction part is arranged between the electrode assembly and the pressure relief mechanism in the first direction, and the first heat conduction part is provided with a pressure relief hole penetrating through the first heat conduction part in the first direction; the orthographic projection of the pressure relief mechanism and the orthographic projection of the pressure relief hole at least partially coincide, so that when the single battery is in thermal runaway, the internal pressure of the shell can act on the pressure relief mechanism through the pressure relief hole, the pressure relief mechanism is promoted to be smoothly started, and the reliability of the pressure relief mechanism of the single battery is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of battery, in particular to a battery monomer, a battery device and a power utilization device. BACKGROUND

[0002] Lithium ion power battery has the performance of high working voltage, large specific energy, small volume, light weight, long cycle life, low self-discharge rate, no memory effect, no pollution, etc., so it is used by many power equipment manufacturers. With the rapid development of lithium battery, the safety problem of battery has also been widely concerned.

[0003] In battery production, a pressure relief mechanism is usually arranged in the battery monomer, and when the battery monomer is in thermal runaway, the pressure relief mechanism can be relieved. How to improve the reliability of the pressure relief mechanism is a problem to be solved. CONTENT OF THE UTILITY MODEL

[0004] In view of the above problems, the present application provides a battery monomer, a battery device and a power utilization device, which can enhance the reliability of the pressure relief mechanism of the battery monomer.

[0005] In the first aspect, the present application provides a battery monomer, comprising: a shell provided with a pressure relief mechanism; an electrode assembly located in the shell; a heat conduction assembly comprising a first heat conduction part, the first heat conduction part and the electrode assembly are in thermal connection, wherein the first heat conduction part is arranged between the electrode assembly and the pressure relief mechanism along a first direction, the first heat conduction part is provided with a pressure relief hole penetrating through the first heat conduction part along the first direction, and the orthogonal projection of the pressure relief mechanism and the orthogonal projection of the pressure relief hole at least partially overlap along the first direction.

[0006] In the scheme of the present application, the battery monomer comprises a shell, an electrode assembly and a heat conduction assembly, the shell is provided with a pressure relief mechanism for relieving the pressure in the shell, the electrode assembly is arranged in the shell, the heat conduction assembly comprises a first heat conduction part, the first heat conduction part and the electrode assembly are in thermal connection, so as to improve the rate of heat exchange between the electrode assembly and the external environment, the first heat conduction part is arranged between the electrode assembly and the pressure relief mechanism, the first heat conduction part is provided with a pressure relief hole penetrating through the first heat conduction part along a first direction, and the orthogonal projection of the pressure relief mechanism and the orthogonal projection of the pressure relief hole at least partially overlap along the first direction, so that at least part of the pressure relief mechanism is exposed from the pressure relief hole, so that when the battery monomer is in thermal runaway, the internal pressure of the shell can act on the pressure relief mechanism through the pressure relief hole, prompting the pressure relief mechanism to start smoothly, so as to improve the reliability of the pressure relief mechanism of the battery monomer.

[0007] In some embodiments, the plurality of electrode assemblies are arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, the second heat conduction part is arranged between two adjacent electrode assemblies, and two accommodation spaces for accommodating the electrode assemblies are formed by the two side surfaces of the second heat conduction part along the second direction and the first heat conduction part, and the two accommodation spaces are in communication with the pressure relief hole.

[0008] In the scheme of the embodiments of the present application, the plurality of electrode assemblies are arranged along a second direction to improve the capacity of the battery monomer, the heat conduction assembly further comprises a second heat conduction part arranged between two adjacent electrode assemblies, the first heat conduction part and the second heat conduction part are connected, the second heat conduction part is used for conducting the heat of the adjacent electrode assemblies and transferring to the first heat conduction part, two accommodation spaces for accommodating the electrode assemblies are formed by the two side surfaces of the second heat conduction part along the second direction and the first heat conduction part, and the two accommodation spaces are in communication with the pressure relief hole, so as to improve the problem that when the battery monomer is in thermal runaway, the pressure in the two accommodation spaces is blocked by the first heat conduction part and cannot be transferred to the pressure relief mechanism, resulting in slow pressure relief rate of the battery monomer and insufficient reliability of the battery monomer.

[0009] In some embodiments, the second heat conduction part is provided with a communication hole penetrating along the second direction.

[0010] In the scheme of the embodiments of the present application, the second heat conduction part is provided with a communication hole penetrating along the second direction, and the gas in the two accommodation cavities can flow through the communication hole to balance the pressure acting on the pressure relief mechanism and improve the reliability of the pressure relief mechanism.

[0011] In some embodiments, the communication hole is arranged at one end of the second heat conduction part close to the first heat conduction part.

[0012] In the scheme of the embodiments of the present application, the middle region of the electrode assembly generates more heat than the edge region, so the communication hole is arranged at one end of the second heat conduction part close to the first heat conduction part to avoid the middle region of the electrode assembly, and the communication hole improves the heat conduction efficiency of the heat conduction assembly in the case of communicating the two accommodation spaces.

[0013] In some embodiments, the communication hole is in communication with the pressure relief hole.

[0014] In the scheme of the embodiments of the present application, the communication hole is in communication with the pressure relief hole to reduce the processing difficulty of the heat conduction assembly.

[0015] In some embodiments, the battery monomer further comprises a support assembly arranged between the shell and the electrode assembly to form a pressure relief space between the electrode assembly and the shell.

[0016] In the scheme of the embodiment of the application, the battery monomer further comprises a support assembly arranged between the shell and the electrode assembly, the support assembly forms a pressure relief space between the electrode assembly and the shell, the pressure relief space is used for buffering the internal pressure of the shell when the battery monomer is in thermal runaway, so as to reduce the risk of explosion or deflagration of the battery monomer in a short time.

[0017] In some embodiments, the support assembly is arranged between the first heat conduction part and the shell, or the support assembly is arranged between the first heat conduction part and the electrode assembly.

[0018] In the scheme of the embodiment of the application, the support assembly is arranged between the first heat conduction part and the shell, so that the first heat conduction part is close to the electrode assembly, so as to improve the heat conduction rate between the electrode assembly and the heat conduction assembly; or the support assembly is arranged between the first heat conduction part and the electrode assembly, so that the first heat conduction part is close to the shell, so as to improve the heat conduction rate between the shell and the heat conduction assembly.

[0019] In some embodiments, the electrode assembly is provided in plurality, the plurality of electrode assemblies are arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, the support assembly is arranged between the first heat conduction part and the electrode assembly, the number of the support assemblies is two, and the two support assemblies are arranged on two sides of the second heat conduction part in the second direction.

[0020] In the scheme of the embodiment of the application, the support assembly is arranged between the first heat conduction part and the electrode assembly, the number of the support assemblies is two, and the two support assemblies are arranged on two sides of the second heat conduction part in the second direction, so as to reduce the risk of mutual interference between the support assembly and the second heat conduction part, resulting in damage to the heat conduction assembly.

[0021] In some embodiments, the electrode assembly is provided in plurality, the plurality of electrode assemblies are arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, the support assembly is arranged between the first heat conduction part and the shell, and a projection of the second heat conduction part in the first direction is located on the support assembly.

[0022] In the scheme of the embodiment of the application, the support assembly is arranged between the first heat conduction part and the shell, and a projection of the second heat conduction part in the first direction is located on the support assembly, so that a single support assembly can support the first heat conduction part forming two accommodating spaces, and the difficulty of cooperation between the support assembly and the heat conduction assembly is reduced.

[0023] In some embodiments, the support assembly comprises an insulating part and at least two raised parts connected to each other, the insulating part is located between the electrode assembly and the raised parts, and each raised part is arranged on a side of the insulating part away from the electrode assembly.

[0024] In the scheme of the embodiment of the present application, the support assembly comprises mutually connected insulation parts and at least two pad parts, the insulation parts are located between the electrode assembly and the pad parts, the pad parts are used to support the insulation parts, the insulation parts are used to support the electrode assembly, each pad part is arranged at the side of the insulation parts away from the electrode assembly, the cross-sectional area of the insulation parts in the first direction is greater than the total cross-sectional area of each pad part in the first direction, so as to improve the contact area of the support assembly and the electrode assembly, and to make the support assembly provide stable support effect on the electrode assembly.

[0025] In some embodiments, the projection of the pressure relief hole in the first direction is at least partially located on the insulation part, and the insulation part is configured to be melted when the internal pressure or temperature of the battery cell reaches a threshold value.

[0026] In the scheme of the embodiment of the present application, the projection of the pressure relief hole in the first direction is at least partially located on the insulation part, so as to improve the contact area of the insulation part and the electrode assembly, and the insulation part is configured to be melted when the internal pressure or temperature of the battery cell reaches a threshold value, so that when the battery cell is in thermal runaway, the gas in the shell can smoothly act on the pressure relief mechanism through the support assembly and the pressure relief hole, and the reliability of the pressure relief mechanism is improved.

[0027] In some embodiments, the size L2 of the support assembly in the first direction satisfies 5mm

[0028] In the scheme of the embodiment of the present application, when the size L2 of the support assembly in the first direction satisfies the above condition, a sufficient volume of pressure relief space is formed between the second end surface and the shell, so as to improve the reliability of the battery cell.

[0029] In some embodiments, along the first direction, the projection of the pressure relief hole is completely located in the projection range of the pressure relief mechanism.

[0030] In the scheme of the embodiment of the present application, along the first direction, the projection of the pressure relief hole is completely located in the projection range of the pressure relief mechanism, so that the internal pressure of the shell can uniformly act on the entire pressure relief mechanism through the pressure relief hole, and the reliability of the pressure relief mechanism is improved.

[0031] In some embodiments, the heat conduction assembly comprises an insulation part and a heat conduction part, the insulation part at least partially forms a containing cavity, the heat conduction part is arranged in the containing cavity, the insulation part comprises a first insulation part, the first insulation part is arranged between the shell and the electrode assembly along the first direction, the heat conduction part comprises a first heat conduction sheet, the first heat conduction sheet is heat-conductively connected to the electrode assembly, the first heat conduction part is composed of the first heat conduction sheet and the first insulation part, wherein the first heat conduction sheet is provided with a first avoiding hole penetrating therethrough, at least part of the first insulation part covers the inner wall of the first avoiding hole, the pressure relief hole is penetratingly arranged in the first insulation part, the pressure relief hole is located in the first avoiding hole, or the pressure relief hole is penetratingly arranged in the first insulation part, and the pressure relief hole and the containing cavity are arranged in a spaced manner.

[0032] In the scheme of the embodiment of the application, the heat conduction assembly includes an insulating part and a heat conduction part. The insulating part forms a containing cavity in at least a partial region, and the heat conduction part is arranged in the containing cavity. The insulating part includes a first insulating part arranged between the shell and the electrode assembly along a first direction. The heat conduction part includes a first heat conduction sheet heat-conductively connected to the electrode assembly. The first heat conduction part is composed of the first heat conduction sheet and the first insulating part. The heat conduction part and the electrode body can be insulated by the insulating part, and the heat conduction part and the electrolyte can be isolated by the insulating part, so as to improve the problem that the incompatibility of the heat conduction part and the electrolyte affects the performance of the battery monomer. The first heat conduction sheet is provided with a first avoiding hole penetrating therethrough. The pressure relief hole is penetratingly arranged in the first insulating part and located in the first avoiding hole, so that the internal pressure of the shell can act on the pressure relief mechanism through the pressure relief hole. At least a part of the first insulating part covers the inner wall of the first avoiding hole, so as to isolate the first heat conduction sheet and the electrolyte through the first insulating part. The pressure relief hole is penetratingly arranged in the first insulating part. The pressure relief hole and the containing cavity are arranged at intervals, so that when the internal pressure of the shell acts on the pressure relief mechanism through the pressure relief hole, the electrolyte and the first heat conduction sheet are prevented from being in contact.

[0033] In some embodiments, the electrode assembly is provided with a plurality of electrode assemblies arranged along a second direction. The first direction and the second direction intersect. The heat conduction assembly further includes a second heat conduction part arranged between two adjacent electrode assemblies. The insulating part further includes a second insulating part connected to the first insulating part. The second insulating part is arranged between the adjacent electrode assemblies along the second direction. The heat conduction part includes a second heat conduction sheet arranged in the second insulating part. The second heat conduction part is composed of the second heat conduction sheet and the second insulating part. The two side surfaces of the second insulating part along the second direction and the first insulating part form two containing spaces for containing the electrode assemblies. The two containing spaces are in communication with the pressure relief hole.

[0034] In the scheme of the embodiment of the application, the two side surfaces of the second insulating part along the second direction and the first insulating part form two containing spaces for containing the electrode assemblies. The two containing spaces are in communication with the pressure relief hole, so as to improve the problem that when the battery monomer is in thermal runaway, the pressure in the two containing spaces is blocked by the first insulating part and cannot be transmitted to the pressure relief mechanism, resulting in a slow pressure relief rate of the battery monomer and insufficient reliability of the battery monomer.

[0035] In some embodiments, the second heat conduction part is provided with a communication hole penetrating therethrough. The second heat conduction sheet is provided with a second avoiding hole penetrating therethrough. At least a part of the second insulating part covers the inner wall of the second avoiding hole. The communication hole is penetratingly arranged in the second insulating part and located in the second avoiding hole, or the communication hole is penetratingly arranged in the second insulating part and arranged at intervals with the containing cavity.

[0036] In the scheme of the embodiment of the application, the second heat-conducting part is provided with a through hole, the second heat-conducting sheet is provided with a second avoiding hole, the through hole is provided in the second insulating part and located in the second avoiding hole, so that the gas in the two accommodation spaces can flow through the through hole, and at least part of the second insulating part covers the inner wall of the second avoiding hole, so as to isolate the second heat-conducting sheet and the electrolyte through the second insulating part; the through hole is provided in the second insulating part, and the through hole and the accommodation cavity are arranged at intervals, so that the gas in the two accommodation spaces can flow through the through hole, and the electrolyte and the first heat-conducting sheet are prevented from being in contact.

[0037] In some embodiments, the electrode assembly includes a first end surface, a second end surface and a side surface, the first end surface and the second end surface are oppositely arranged along a first direction, and the side surface is connected between the first end surface and the second end surface, the side surface includes two first side surfaces oppositely arranged in a second direction and two second side surfaces oppositely arranged in a third direction, the first direction, the second direction and the third direction intersect with each other, the insulating part further includes two third insulating parts, the third insulating part includes a body part and a bent part connected with each other, the body parts of the two third insulating parts are arranged at the two first side surfaces respectively, and the bent parts are arranged at the two second side surfaces respectively, and the heat-conducting part includes a third heat-conducting sheet arranged in at least one of the body part and the bent part.

[0038] In the scheme of the embodiment of the application, the third insulating part includes a body part and a bent part connected with each other, the body parts of the two third insulating parts are arranged at the two first side surfaces respectively, and the bent parts are arranged at the two second side surfaces respectively, so as to realize the insulation of the electrode assembly on the circumferential surface and the shell, and the third heat-conducting sheet is arranged in at least one of the body part and the bent part, so as to improve the heat-conducting rate at the first side surface and / or the second side surface of the electrode assembly.

[0039] In some embodiments, the body part is connected with one bent part on each side in the third direction, and the two bent parts of the two third insulating parts located on the same side of the electrode assembly extend towards each other in the second direction.

[0040] In the scheme of the embodiment of the application, the body part is connected with one bent part on each side in the third direction, and the two bent parts of the two third insulating parts located on the same side of the electrode assembly extend towards each other in the second direction, so that the spliced part of the two bent parts is located on the second side surface, and the first side surface with a larger area can be provided with a third heat-conducting sheet with a larger area, so as to improve the heat-conducting capacity of the heat-conducting assembly.

[0041] In some embodiments, the thickness D1 of the heat-conducting part satisfies 40 μm≤D1≤180 μm.

[0042] In the scheme of the embodiment of the application, when the above condition is met, the problem of the battery monomer volume being too large and the energy density being reduced due to the heat conduction member being too thick can be improved, and the problem of the heat conduction member being easily damaged due to the heat conduction member being too thin can also be improved.

[0043] In some embodiments, the insulating member comprises polyethylene or polypropylene or polyimide or polyester resin.

[0044] In the scheme of the embodiment of the application, the insulating member comprises polyethylene or polypropylene or polyimide or polyester resin, so as to improve the insulation reliability of the insulating member.

[0045] In some embodiments, the heat conduction member comprises graphite or graphene or carbon nanotube.

[0046] In the scheme of the embodiment of the application, the heat conduction member comprises graphite or graphene or carbon nanotube, so as to improve the heat conduction performance of the heat conduction assembly by using the graphite or graphene or carbon nanotube heat conduction material.

[0047] In some embodiments, the heat conductivity k of the heat conduction member satisfies k≥500 W / (m·K).

[0048] In the scheme of the embodiment of the application, when the heat conductivity k of the heat conduction member satisfies the above condition, the heat conduction assembly has sufficient heat conduction performance to conduct the heat of the electrode main body.

[0049] In a second aspect, the embodiment of the application provides a battery device, comprising the battery monomer of any one of the embodiments of the first aspect.

[0050] In a third aspect, the embodiment of the application provides a power consumption device, comprising the battery device of the embodiment of the second aspect. BRIEF DESCRIPTION OF DRAWINGS

[0051] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of preferred embodiments, and are not meant to limit the application. Moreover, the same reference numerals in different figures represent the same or similar components. In the drawings:

[0052] Figure 1 is a structural schematic diagram of a vehicle provided by an embodiment of the application;

[0053] Figure 2 is a structural schematic diagram of a battery device provided by an embodiment of the application;

[0054] Figure 3 is a structural schematic diagram of a battery module provided by an embodiment of the application;

[0055] Figure 4is an exploded view of a battery cell provided by an embodiment of the present application;

[0056] Figure 5 is a structural schematic view of an electrode assembly of a battery cell provided by an embodiment of the present application;

[0057] Figure 6 is a structural schematic view of a shell of a battery cell provided by an embodiment of the present application;

[0058] Figure 7 is a structural schematic view of a heat-conducting assembly of a battery cell provided by an embodiment of the present application;

[0059] Figure 8 is a partial structural schematic view of a battery cell provided by an embodiment of the present application;

[0060] Figure 9 is a partial structural schematic view of a battery cell provided by an embodiment of the present application;

[0061] Figure 10 is an exploded view of a battery cell provided by an embodiment of the present application;

[0062] Figure 11 is a partial structural schematic view of a battery cell provided by an embodiment of the present application;

[0063] Figure 12 is Figure 11 is a sectional view at A-A in FIG. 7;

[0064] Figure 13 is a partial structural schematic view of a battery cell provided by an embodiment of the present application;

[0065] Figure 14 is a structural schematic view of a support assembly of a battery cell provided by an embodiment of the present application;

[0066] Figure 15 is a sectional view of a heat-conducting assembly of a battery cell provided by an embodiment of the present application;

[0067] Figure 16 is a structural schematic view of a heat-conducting assembly of a battery cell provided by an embodiment of the present application;

[0068] Figure 17 is a structural schematic view of a first heat-conducting part of a battery cell provided by an embodiment of the present application;

[0069] Figure 18 is a structural schematic view of a first heat-conducting part of a battery cell provided by another embodiment of the present application;

[0070] Figure 19 is Figure 16 is an enlarged structural schematic view at B in FIG. 7;

[0071] Figure 20 is a structural schematic diagram of a second heat conduction part of a battery monomer provided by an embodiment of the present application.

[0072] Figure 21 is a structural schematic diagram of a second heat conduction part of a battery monomer provided by another embodiment of the present application.

[0073] Reference signs:

[0074] 1, vehicle; 101, motor; 102, controller; 2, battery device; 201, battery module; 202, box; 2021, first box; 2022, second box;

[0075] 3, battery monomer;

[0076] 4, shell; 41, pressure relief mechanism;

[0077] 5, electrode assembly; 51, tab; 52, electrode body; 521, first end face; 522, second end face; 523, side face; 5231, first side face; 5232, second side face;

[0078] 6, top cover assembly; 7, switching mechanism;

[0079] 8, heat conduction assembly; 81, first heat conduction part; 82, second heat conduction part; 83, third heat conduction part; 811, pressure relief hole; 821, containing space; 822, communication hole;

[0080] 84, heat conduction piece; 85, insulation piece; 851, containing cavity; 852, first insulation part; 853, second insulation part; 841, first heat conduction sheet; 842, second heat conduction sheet; 843, third heat conduction sheet; 8414, first avoiding hole; 8421, second avoiding hole; 854, third insulation part; 8541, body part; 8542, bending part;

[0081] 9, support assembly; 91, insulation part; 92, pad part;

[0082] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0083] The embodiments of the technical scheme of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical scheme of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0084] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should be understood as the usual meanings understood by the persons skilled in the art to which the embodiments of the present application belong.

[0085] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0086] In addition, the technical terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0087] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0088] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0089] At present, from the development of market situation, the application of battery device is more and more widely. The battery device is not only applied to the energy storage power supply system of hydropower, thermal power, wind power and solar power station, but also widely applied to electric bicycles, electric motorcycles, electric vehicles and other electric vehicles, military equipment, aerospace and other fields. With the continuous expansion of the application field of battery device, the market demand is also increasing.

[0090] In battery production, a pressure relief mechanism is usually arranged in a battery cell, and the pressure relief mechanism can relieve pressure when the battery cell is in thermal runaway. However, the reliability of the pressure relief mechanism still needs to be improved.

[0091] The above problem is caused by the fact that, in order to improve the heat dissipation efficiency of the electrode assembly, an electrically conductive assembly is arranged in the shell, the electrically conductive assembly includes a first heat-conducting part arranged between the second end surface of the electrode assembly and the pressure relief mechanism. When the battery cell is in thermal runaway, part of the gas in the shell is blocked by the first heat-conducting part and cannot directly act on the pressure relief mechanism, resulting in insufficient reliability of the pressure relief mechanism.

[0092] Based on the above problem, the embodiments of the present application provide a battery cell, which includes a shell, an electrode assembly, and a heat-conducting assembly. The shell is provided with a pressure relief mechanism for relieving the pressure in the shell. The electrode assembly is arranged in the shell. The heat-conducting assembly includes a first heat-conducting part. The first heat-conducting part is in thermal conductive connection with the electrode assembly, so as to improve the rate of heat exchange between the electrode assembly and the external environment. The first heat-conducting part is arranged between the electrode assembly and the pressure relief mechanism. The first heat-conducting part is provided with a pressure relief hole penetrating the first heat-conducting part in a first direction. In the first direction, the orthographic projection of the pressure relief mechanism and the orthographic projection of the pressure relief hole at least partially overlap, so that at least part of the pressure relief mechanism is exposed from the pressure relief hole. When the battery cell is in thermal runaway, the pressure in the shell can act on the pressure relief mechanism through the pressure relief hole, so as to smoothly start the pressure relief mechanism, thereby improving the reliability of the pressure relief mechanism of the battery cell.

[0093] The technical solutions described in the embodiments of the present application are applicable to battery devices and electric devices using the battery devices.

[0094] The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile, or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game machine, an electric automobile toy, an electric ship toy, and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool, and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator, and an electric planer, etc. The embodiments of the present application do not specially limit the above electric devices.

[0095] In the embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0096] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead-acid battery, etc. The embodiments of the present application are not limited thereto. The battery cell can be in the shape of a cylinder, a flat body, a cuboid or other shapes, etc. The embodiments of the present application are not limited thereto.

[0097] The battery device mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery device mentioned in the present application can include a battery module or a battery pack, etc. The battery pack generally includes a box for packaging one or more battery cells. The box can avoid the influence of liquid or other foreign matters on the charging or discharging of the battery cell.

[0098] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive current collector and a positive active material layer, and the positive active material layer is coated on the surface of the positive current collector; the positive current collector includes a positive current collecting portion and a positive tab connected to the positive current collecting portion, and the positive current collecting portion is coated with the positive active material layer, and the positive tab is not coated with the positive active material layer. Taking a lithium ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material, which can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, and the negative active material layer is coated on the surface of the negative current collector; the negative current collector includes a negative current collecting portion and a negative tab connected to the negative current collecting portion, and the negative current collecting portion is coated with the negative active material layer, and the negative 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 a negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0099] It should be understood that the technical solutions described in the embodiments of the present application are not only limited to the above-described battery device and electric equipment, but can also be applied to all battery devices including a box and electric equipment using the battery device. However, for the sake of brevity of description, the following embodiments are described taking an electric vehicle as an example.

[0100] Please refer to Figure 1 , Figure 1A schematic diagram of a vehicle 1 is provided for some embodiments of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle, or a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or a range extended vehicle, etc. The vehicle 1 is internally provided with a battery device 2, which can be arranged at the bottom, head or tail of the vehicle 1. The battery device 2 can be used for power supply of the vehicle 1, for example, the battery device 2 can be used as an operating power source of the vehicle 1. The vehicle 1 can further include a controller 102 and a motor 101, the controller 102 being used to control the battery to supply power to the motor 101, for example, for the power demand of the vehicle 1 during starting, navigation and driving.

[0101] In some embodiments of the present application, the battery device 2 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1.

[0102] Figure 2 A schematic diagram of a battery device according to an embodiment of the present application is shown.

[0103] The battery device 2 mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells 3 connected in series, in parallel or in a mixed manner through a busbar component.

[0104] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells 3.

[0105] As an example, the battery cell assembly can be a battery module 201 formed by arranging and fixing a plurality of battery cells 3 into an independent module. As an example, the battery module 201 can be formed by bundling a plurality of battery cells 3 with a cable tie.

[0106] In some embodiments, the battery device can be a battery pack including a box 202 and one or more battery cell assemblies accommodated in the box 202.

[0107] As an example, the battery cell assembly can be a battery module 201, which can be accommodated in the box 202 by fixing the battery module 201 in the box.

[0108] As an example, the battery cell assembly can also be accommodated in the box 202 by directly fixing a plurality of battery cells 3 in the box 202.

[0109] As an example, the box 202 can include a first box 2021 and a second box 2022. The first box 2021 and the second box 2022 are fastened so that an enclosed space is formed inside the box 202 to accommodate the battery cell assembly. The enclosed here means covered or closed, which can be sealed or non-sealed. The first box 2021 can be a top cover or a bottom plate.

[0110] As an example, the box 202 can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are connected with the frame, respectively, so that an enclosed space is formed inside the box 202 to accommodate the battery cell assembly.

[0111] In some embodiments, the box 202 can be part of the chassis structure of the vehicle. For example, part of the box 202 can be at least part of the floor of the vehicle, or part of the box 202 can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0112] Figure 3 A structural diagram of the battery module 201 of an embodiment of the present application is shown.

[0113] In some embodiments, as shown in Figure 2 and Figure 3 , the battery cell 3 is multiple, and the multiple battery cells 3 are connected in series or in parallel or in hybrid connection to form a battery module 201. Multiple battery modules 201 are connected in series or in parallel or in hybrid connection to form a whole and are accommodated in the box 202.

[0114] The multiple battery cells 3 in the battery module 201 can be electrically connected through a busbar component to realize parallel connection, series connection, or hybrid connection of the multiple battery cells 3 in the battery module 201.

[0115] Figure 4 An exploded view of the battery cell provided by an embodiment of the present application is shown. The battery cell 3 refers to the smallest unit that constitutes a battery device. As shown in Figure 4 , the battery cell 3 includes a top cover assembly 6, a housing 4, and an electrode assembly 5.

[0116] The electrode assembly 5 is a component in the battery cell 3 where electrochemical reactions occur. The housing 4 can contain one or more electrode assemblies 5. The electrode assembly 5 is mainly formed by winding or stacking the electrode sheet, which is divided into positive electrode sheets and negative electrode sheets, and usually has a separator between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have a part of the active material constituting the electrode body 52, and each of the positive electrode sheet and the negative electrode sheet has a part not having the active material constituting the tab 51. The positive electrode tab and the negative electrode tab can be located at one end of the electrode body 52 or at two ends of the electrode body 52, respectively. In the charging and discharging process of the battery cell 3, the positive active material and the negative active material react with the electrolyte, and the tab 51 connects the electrode terminal to form a current loop.

[0117] The electrode assembly 5 can be in a wound structure, a stacked structure, or a hybrid structure of the wound and stacked structures.

[0118] In some embodiments, the electrode assembly 5 is in a wound structure. The positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0119] In some embodiments, the electrode assembly 5 is in a stacked structure. As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets are alternately stacked, and a plurality of separators are provided between any adjacent positive electrode sheets or negative electrode sheets. Alternatively, the separators can be continuously provided and arranged between any adjacent positive electrode sheets or negative electrode sheets by folding.

[0120] In some embodiments, the electrode assembly 5 can have a cylindrical shape, a flat shape, or a polygonal shape.

[0121] In some embodiments, the electrode assembly 5 is provided with tabs, which can guide the current out of the electrode assembly. The tabs include positive tabs and negative tabs.

[0122] The battery cell 3 can include a case 4. The case 4 is a component for cooperating with the top cover assembly 6 to form an internal environment of the battery cell 3, where the formed internal environment can be used to accommodate the electrode assembly 5, electrolyte (not shown in the figure), and other components. The case 4 can be a steel case, an aluminum case, a plastic case (such as polypropylene), a composite metal case (such as a copper-aluminum composite case), or an aluminum-plastic film, etc. In some embodiments, the case 4 can be a sealed structure or a non-sealed structure. As an example, when the case 4 is a non-sealed structure, the case 4 serves to protect the electrode assembly 5, and a sealing bag is further included between the case 4 and the electrode assembly 5, which is used to package the electrode assembly and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film. When the case 4 is a sealed structure, it is used to package the electrode assembly 5, the electrolyte, and other components.

[0123] 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, including a square battery cell, a blade battery cell, a polygonal battery cell (such as a hexagonal battery cell), etc., without specific limitation in the present application.

[0124] The case 4 and the top cover assembly 6 can be independent components, and one or more openings can be provided on the case 4, and the one or more top cover assemblies 6 cover the openings to form the internal environment of the battery cell 3. Alternatively, the top cover assembly 6 and the case 4 can be integrated. Alternatively, the top cover assembly 6 and the case 4 can form a common connecting surface before other components enter the case, and then the top cover assembly 6 covers the case 4 when it is necessary to seal the inside of the case 4.

[0125] In some embodiments, the electrode terminal can be arranged on the top cover assembly 6 or on the shell 4, and the electrode terminal is electrically connected with the tab 51. The electrode terminal can be directly connected with the tab 51 or indirectly connected with the tab 51 through the adapter mechanism 7.

[0126] Please refer to Figure 5 , Figure 6 , Figure 7 and Figure 8 , Figure 5 is a structural schematic diagram of an electrode assembly of a battery monomer provided by an embodiment of the present application; Figure 6 is a structural schematic diagram of a shell of a battery monomer provided by an embodiment of the present application; Figure 7 is a structural schematic diagram of a heat conduction assembly of a battery monomer provided by an embodiment of the present application; Figure 8 is a partial structural schematic diagram of a battery monomer provided by an embodiment of the present application.

[0127] The first aspect, as shown in Figure 4 to Figure 8 , the present application provides a battery monomer 3, the battery monomer 3 includes a shell 4, an electrode assembly 5 and a heat conduction assembly 8, the shell 4 is provided with a pressure relief mechanism 41; the electrode assembly 5 is located in the shell 4; the heat conduction assembly 8 includes a first heat conduction part 81, the first heat conduction part 81 and the electrode assembly 5 are in thermal connection, wherein the first heat conduction part 81 is arranged between the electrode assembly 5 and the pressure relief mechanism 41, the first heat conduction part 81 is provided with a pressure relief hole 811 penetrating through the first heat conduction part 81 along a first direction X, along the first direction X, the orthographic projection of the pressure relief mechanism 41 and the orthographic projection of the pressure relief hole 811 at least partially coincide.

[0128] In the scheme of the embodiment of the present application, the battery monomer 3 includes a shell 4, an electrode assembly 5 and a heat conduction assembly 8, the shell 4 is provided with a pressure relief mechanism 41 for releasing the pressure in the shell 4, the shell 4 is provided with the electrode assembly 5, the heat conduction assembly 8 includes a first heat conduction part 81, the first heat conduction part 81 and the electrode assembly 5 are in thermal connection, the rate of heat exchange between the electrode main body 52 and the external environment is improved, the first heat conduction part 81 is arranged between the electrode assembly 5 and the pressure relief mechanism 41, the first heat conduction part 81 is provided with a pressure relief hole 811 penetrating through the first heat conduction part 81 along a first direction X, along the first direction X, the orthographic projection of the pressure relief mechanism 41 and the orthographic projection of the pressure relief hole 811 at least partially coincide, so that at least part of the pressure relief mechanism 41 is exposed by the pressure relief hole 811, so that when the battery monomer 3 is in thermal runaway, the internal pressure of the shell 4 can act on the pressure relief mechanism 41 through the pressure relief hole 811, prompting the pressure relief mechanism 41 to start smoothly, so as to improve the reliability of the pressure relief mechanism 41 of the battery monomer 3.

[0129] The electrode assembly 5 includes an electrode body 52 and a tab 51, the electrode body 52 includes a first end face 521, a second end face 522 and a side face 523 connecting the first end face 521 and the second end face 522, and the tab 51 is connected to the electrode body 52. The electrode body 52 is formed by a separator, a positive electrode sheet and a negative electrode sheet in a winding or stacking manner. The tab 51 includes a positive tab and a negative tab, and both the positive tab and the negative tab extend out of the first end face 521 or the second end face 522.

[0130] For example, the battery cell 3 further includes a top cover assembly 6 connected to the tab 51, the housing 4 includes an opening at one end close to the first end face 521 in the first direction X, and the top cover assembly 6 covers the opening. An electrode terminal can be arranged on the top cover assembly 6, and the positive tab and the negative tab extend out of the first end face 521 and are connected to the electrode terminal on the top cover assembly 6.

[0131] For example, the first direction X is a height direction of the electrode assembly 5, the first end face 521 and the second end face 522 are arranged opposite to each other in the first direction, the tab 51 extends out of the first end face 521, and the pressure relief hole 811 is arranged between the second end face 522 and the pressure relief mechanism 41. Alternatively, the first direction X is a length or width direction of the electrode assembly 5, the arrangement direction of the first end face 521 and the second end face 522 intersects the first direction, the tab 51 extends out of the first end face 521 or the second end face 522, and the pressure relief hole 811 is arranged between the side face 523 and the pressure relief mechanism 41.

[0132] For example, the pressure relief mechanism 41 is actuated to release the internal pressure or temperature when the internal pressure or temperature of the battery cell 3 reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 3 reaches the predetermined threshold, the pressure relief mechanism 41 performs an action or a weak structure provided in the pressure relief mechanism 41 is damaged, thereby forming an opening or a passage for the internal pressure or temperature to be released. The threshold is designed differently according to different design requirements. The threshold can depend on the material of one or more of the positive electrode sheet, the negative electrode sheet, the electrolyte and the separator in the battery cell.

[0133] For example, the pressure relief mechanism 41 can be integrally formed with the housing 4, for example, a notch is made on the housing 4 to form a weak structure, and the weak structure serves as the pressure relief mechanism 41.

[0134] The pressure relief mechanism 41 can also be provided separately from the housing 4 and connected to the housing 4, for example, the pressure relief mechanism 41 is connected to the housing 4 by welding or other components. For example, a notch is provided on the pressure relief mechanism 41 to form a weak structure.

[0135] For example, the pressure relief mechanism 41 can take the form of a relief valve, a balance valve, a gas valve, a pressure relief valve or a safety valve, etc.

[0136] The "actuation" mentioned in the present application refers to the action or activation of the pressure relief mechanism 41 to a certain state, so that the internal pressure and temperature of the battery monomer 3 can be released. The action of the pressure relief mechanism 41 can include but is not limited to: the movement of the components in the pressure relief mechanism 41 to form an exhaust passage, the rupture, fragmentation, tearing or opening of at least a part of the pressure relief mechanism 41, etc. When the pressure relief mechanism 41 is actuated, the high-temperature and high-pressure substances in the interior of the battery monomer 3 will be discharged outward from the actuated part as exhaust. In this way, the battery monomer 3 can be depressurized and cooled at a controllable pressure or temperature, thereby avoiding potential more serious accidents.

[0137] The exhaust from the battery monomer 3 mentioned in the present application includes but is not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separator film, high-temperature and high-pressure gases generated by reaction, flames, etc.

[0138] The first heat-conducting part 81 is in heat-conducting connection with the electrode assembly 5, so that the first heat-conducting part 81 is directly attached to or abuts against the electrode body 52; or the first heat-conducting part 81 is a plating layer provided on the electrode body 52; or the first heat-conducting part 81 is spaced apart from the electrode body 52, and the first heat-conducting part 81 is connected to the electrode body 52 through a heat-conducting medium, which can be air or metal or heat-conducting glue, etc.

[0139] During the operation of the battery monomer 3, the heat generated by the electrode body 52 can be transmitted to the external environment through the heat-conducting assembly 8, thereby improving the problem of damage of the electrode body 52 due to excessively high temperature; or in a low-temperature environment, the heat-conducting assembly 8 can conduct the heat from the external environment to the electrode body 52 to heat the electrode assembly 5.

[0140] Optionally, the battery device 2 comprises a heat exchange mechanism, the shell 4 of the battery monomer 3 is in heat-conducting connection with the heat exchange mechanism, and the heat-conducting assembly 8 can conduct heat between the heat exchange mechanism and the electrode assembly 5. The heat exchange mechanism can conduct heat into or out of the heat-conducting assembly 8.

[0141] Exemplarily, the heat exchange mechanism can be a water-cooled plate or a phase-change heat dissipation plate provided on the outer surface of the battery monomer 3, or a cavity containing a heat exchange medium.

[0142] The first heat-conducting part 81 can be in a strip shape or a flat plate shape or a mesh plate shape, etc. The first heat-conducting part 81 can be in a rectangular shape or a circular shape or a rhombic shape, etc. The specific shape and size of the first heat-conducting part 81 can be designed flexibly.

[0143] The first heat-conducting part 81 is provided with a pressure relief hole 811 penetrating therethrough. The shape and size of the pressure relief hole 811 can be designed as desired. Exemplarily, the pressure relief hole 811 is a circular hole or a rectangular hole, etc.

[0144] The at least partial pressure relief mechanism 41 is exposed by the pressure relief hole 811, the at least partial pressure relief mechanism 41 is coincided with the orthographic projection of the first heat conduction part 81, the gas inside the shell 4 can directly act on the pressure relief mechanism 41 through the pressure relief hole 811 along the first direction X, so that the gas inside the shell 4 can start the pressure relief mechanism 41 to release the pressure inside the shell 4 when the battery monomer 3 is in thermal runaway.

[0145] In some embodiments, as shown in Figure 4 、 Figure 7 and Figure 8 , along the first direction X, the orthographic projection of the pressure relief hole 811 is completely located in the orthographic projection range of the pressure relief mechanism 41.

[0146] In these embodiments, along the first direction X, the orthographic projection of the pressure relief hole 811 is completely located in the orthographic projection range of the pressure relief mechanism 41, and the pressure relief mechanism 41 is completely exposed to the pressure relief hole 811, so that the pressure inside the shell 4 can uniformly act on the entire pressure relief mechanism 41 through the pressure relief hole 811, thereby improving the reliability of the pressure relief mechanism 41.

[0147] Optionally, the pressure relief hole 811 and the pressure relief mechanism 41 are the same shape, so that in the case that the orthographic projection of the pressure relief hole 811 is completely located in the orthographic projection range of the pressure relief mechanism 41 along the first direction X, the size of the pressure relief hole 811 is reduced, and the heat conduction efficiency of the first heat conduction part 81 is improved. For example, the pressure relief mechanism 41 is circular, and the pressure relief hole 811 is a circular hole; the pressure relief mechanism 41 is elliptical, and the pressure relief hole 811 is a waist-shaped hole, etc.

[0148] Please refer to Figure 9 , Figure 9 is a partial structure schematic diagram of a battery monomer provided by an embodiment of the application.

[0149] In some embodiments, as shown in Figure 4 、 Figure 7 and Figure 9 , the electrode assembly 5 is provided with a plurality of electrode assemblies 5, the plurality of electrode assemblies 5 are arranged along the second direction Y, the first direction X and the second direction Y intersect, the heat conduction assembly 8 further includes a second heat conduction part 82, the first heat conduction part 81 and the second heat conduction part 82 are connected, the second heat conduction part 82 is arranged between two adjacent electrode assemblies 5, the two side surfaces of the second heat conduction part 82 along the second direction Y and the first heat conduction part 81 form two accommodation spaces 821 for accommodating the electrode assembly 5, and the two accommodation spaces 821 are in communication with the pressure relief hole 811.

[0150] In the embodiments, the plurality of electrode assemblies 5 are arranged along the second direction Y to improve the capacity of the battery cell 3. The heat conduction assembly 8 further comprises a second heat conduction part 82 arranged between two adjacent electrode assemblies 5. The first heat conduction part 81 and the second heat conduction part 82 are connected. The second heat conduction part 82 is used to conduct the heat of the adjacent electrode assemblies 5 and transfer to the first heat conduction part 81. The two side surfaces of the second heat conduction part 82 along the second direction Y and the first heat conduction part 81 form two accommodation spaces 821 for accommodating the electrode assemblies 5. The two accommodation spaces 821 are both in communication with the pressure relief hole 811, so as to improve the problem that the pressure in the two accommodation spaces 821 cannot be transferred to the pressure relief mechanism 41 due to the blockage of the first heat conduction part 81 when the battery cell 3 is in thermal runaway, resulting in slow pressure relief rate of the battery cell 3 and insufficient reliability of the battery cell 3.

[0151] The heat between the adjacent electrode assemblies 5 is not easy to exchange with the outside through the shell 4. Therefore, in the embodiments, the second heat conduction part 82 is arranged between the adjacent electrode assemblies 5. The heat of the two adjacent electrode assemblies 5 is transferred to the second heat conduction part 82 and then transferred to the first heat conduction part 81 by the second heat conduction part 82. The heat exchanges with the outside environment at the first heat conduction part 81.

[0152] Optionally, the heat conduction assembly 8 comprises a first heat conduction part 81 and a second heat conduction part 82. The two electrode assemblies 5 are arranged on the same side of the first heat conduction part 81. The second heat conduction part 82 is arranged between the two electrode assemblies 5 and connected to the middle region of the first heat conduction part 81. The two side surfaces of the second heat conduction part 82 and the first heat conduction part 81 form two accommodation spaces 821. A pressure relief hole 811 extends on both sides of the second heat conduction part 82, which reduces the processing difficulty of the pressure relief hole 811, so that the two accommodation spaces 821 are in communication with the pressure relief hole 811. Alternatively, two pressure relief holes 811 are arranged on the first heat conduction part 81 at intervals. The second heat conduction part 82 is located between the two pressure relief holes 811. The two pressure relief holes 811 are respectively in communication with the two accommodation spaces 821, so as to reduce the setting area of a single pressure relief hole 811 and improve the structural strength of the first heat conduction part 81.

[0153] Illustratively, the heat conduction assembly 8 comprises two second heat conduction parts 82 and two first heat conduction parts 81. The two electrode assemblies 5 are arranged on the same side of the two first heat conduction parts 81. The two second heat conduction parts 82 are located between the two electrode assemblies 5. Each second heat conduction part 82 is connected to each first heat conduction part 81, or the first heat conduction part 81 and the second heat conduction part 82 are formed by bending the same base material, so as to reduce the processing difficulty of the heat conduction assembly 8. Each first heat conduction part 81 and each second heat conduction part 82 form an accommodation space 821. Each first heat conduction part 81 is provided with a pressure relief hole 811, so that each accommodation space 821 is in communication with the pressure relief hole 811.

[0154] Optionally, the pressure relief holes 811 are located at portions of the accommodation spaces 821 with the same area, so as to balance the pressure relief rates of the two accommodation spaces 821.

[0155] In some embodiments, as shown in Figure 7 and Figure 9 The second heat-conducting part 82 is provided with a communication hole 822 along the second direction Y.

[0156] In these embodiments, the second heat-conducting part 82 is provided with a communication hole 822 along the second direction Y, and the gases in the two accommodation cavities 851 can flow through the communication hole 822, so as to balance the pressure acting on the pressure relief mechanism 41 and improve the reliability of the pressure relief mechanism 41.

[0157] The second heat-conducting part 82 is provided with a communication hole 822, and the gases in the two accommodation spaces 821 can flow through the communication hole 822, so as to balance the pressure of the two accommodation spaces 821.

[0158] Optionally, the second heat-conducting part 82 is provided with at least two communication holes 822, so as to improve the flow rate of the gases.

[0159] Optionally, the communication hole 822 can be designed in various shapes and sizes, for example, the communication hole 822 can be a circular hole or a rectangular hole.

[0160] In some embodiments, as shown in Figure 7 and Figure 9 The communication hole 822 is arranged at one end of the second heat-conducting part 82 close to the first heat-conducting part 81.

[0161] In these embodiments, the middle region of the electrode assembly 5 generates more heat than the edge region, and therefore the communication hole 822 is arranged at one end of the second heat-conducting part 82 close to the first heat-conducting part 81 to avoid the middle region of the electrode assembly 5. In the case that the communication hole 822 connects the two accommodation spaces 821, the arrangement of the communication hole 822 improves the heat-conducting efficiency of the heat-conducting assembly 8.

[0162] The communication hole 822 is arranged at one end of the second heat-conducting part 82 close to the first heat-conducting part 81, and the size of the communication hole 822 along the first direction X to the first heat-conducting part 81 is less than half of the size of the second heat-conducting part 82 in the first direction X, so as to make the communication hole 822 avoid the middle region of the second heat-conducting part 82 in the first direction X.

[0163] During the operation of the electrode assembly 5, the temperature of one end of the electrode body 52 close to the tab 51 is relatively high, and the temperature of the other end away from the tab 51 is relatively low. The communication hole 822 is arranged at one end of the second heat-conducting part 82 close to the first heat-conducting part 81, so as to reduce the influence of the arrangement of the communication hole 822 on the heat-conducting performance of the heat-conducting assembly 8.

[0164] Optionally, the communication hole 822 is arranged at a side edge of the second heat conduction part 82 close to the first heat conduction part 81, so as to reduce the influence of the arrangement of the communication hole 822 on the heat conduction performance of the heat conduction assembly 8.

[0165] In some embodiments, as shown in Figure 7 , Figure 9 the communication hole 822 and the pressure relief hole 811 are in communication.

[0166] In these embodiments, the communication hole 822 and the pressure relief hole 811 are in communication, so as to reduce the processing difficulty of the heat conduction assembly 8.

[0167] The communication hole 822 is arranged at a side edge of the second heat conduction part 82 close to the first heat conduction part 81, and the communication hole 822 is in coincidence with the pressure relief hole 811 in the orthographic projection of the first heat conduction part 81.

[0168] Please refer to Figure 10 , Figure 10 is an exploded view of the battery cell provided in an embodiment of the present application.

[0169] In some embodiments, as shown in Figure 6 , Figure 7 and Figure 10 the battery cell 3 further comprises a support assembly 9 arranged between the shell 4 and the electrode assembly 5, so as to form a pressure relief space between the electrode assembly 5 and the shell 4.

[0170] In these embodiments, the battery cell 3 further comprises a support assembly 9 arranged between the shell 4 and the electrode assembly 5, and the support assembly 9 forms a pressure relief space between the electrode assembly 5 and the shell 4, and the pressure relief space is used to buffer the internal pressure of the shell 4 when the battery cell 3 is in thermal runaway, so as to reduce the risk of explosion or deflagration of the battery cell 3 in a short time.

[0171] The support assembly 9 is arranged inside the shell 4 and supports the electrode assembly 5 from the shell 4, so as to form a pressure relief space between the electrode assembly 5 and the shell 4, so as to buffer the internal pressure of the shell 4 when the battery cell 3 is in thermal runaway. The specific size and shape of the support assembly 9 can be designed by itself.

[0172] Specifically, the first heat conduction part 81 is arranged between the support assembly 9 and the electrode assembly 5, and the support assembly 9 is arranged between the pressure relief hole 811 and the pressure relief mechanism 41; or the first heat conduction part 81 is arranged between the support assembly 9 and the shell 4, and the support assembly 9 is arranged between the pressure relief hole 811 and the electrode assembly 5.

[0173] Optionally, the support assembly 9 and the electrode assembly 5 are insulated from each other, so as to reduce the risk of accidental conduction of the electrode assembly 5 through the support assembly 9 and the shell 4. For example, the support assembly 9 is made of insulating material, or an insulating material layer is arranged on the side surface of the support assembly 9 facing the electrode assembly 5.

[0174] Optionally, the support assembly 9 is projected in the first direction X to cover the electrode assembly 5, so as to increase the contact area between the support assembly 9 and the electrode assembly 5, and to improve the support stability of the support assembly 9.

[0175] Optionally, at least two support assemblies 9 are arranged at intervals to jointly support the electrode assembly 5, so as to facilitate adjustment of the support position of the support assembly 9 on the electrode assembly 5 in different battery monomers 3.

[0176] Optionally, the support assembly 9 can be in a plate shape; or the support assembly 9 comprises a plurality of support blocks arranged at intervals.

[0177] Optionally, a pressure relief channel is arranged through the support assembly 9 and is communicated with the pressure relief hole 811, so as to facilitate the gas inside the shell 4 to pass through the pressure relief hole 811.

[0178] Please refer to Figure 11 、 Figure 12 and Figure 13 , Figure 11 is a partial structure diagram of a battery monomer provided in an embodiment of the present application; Figure 12 is Figure 11 a sectional view at A-A in Figure 13 is a partial structure diagram of a battery monomer provided in an embodiment of the present application.

[0179] In some embodiments, as shown in Figure 10 to Figure 13 , the support assembly 9 is arranged between the first heat conduction part 81 and the shell 4, or the support assembly 9 is arranged between the first heat conduction part 81 and the electrode assembly 5.

[0180] In these embodiments, the support assembly 9 is arranged between the first heat conduction part 81 and the shell 4, so that the first heat conduction part 81 is close to the electrode assembly 5, so as to improve the heat conduction rate between the electrode assembly 5 and the heat conduction assembly 8; or the support assembly 9 is arranged between the first heat conduction part 81 and the electrode assembly 5, so that the first heat conduction part 81 is close to the shell 4, so as to improve the heat conduction rate between the shell 4 and the heat conduction assembly 8.

[0181] The support assembly 9 is arranged between the first heat conduction part 81 and the shell 4, as shown in Figure 13As shown, the support component 9 is disposed on the side of the first heat-conducting part 81 away from the electrode assembly 5. The support component 9 supports the heat-conducting part 8 and the electrode assembly 5. The gas inside the housing 4 can act on the pressure relief mechanism 41 through the pressure relief hole 811 and the support component 9. For example, the heat-conducting part 8 also includes a third heat-conducting part 83, which is disposed between the electrode assembly 5 and the housing 4 along the second direction Y. The heat exchange mechanism is arranged along the second direction Y and the battery cell 3. The heat from the first heat-conducting part 81 and the second heat-conducting part 82 is transferred to the third heat-conducting part 83 and exchanges heat with the heat exchange mechanism. At this time, the support component 9 is disposed between the first heat-conducting part 81 and the housing 4. The first heat-conducting part 81 is close to the electrode assembly 5 to facilitate the transfer of heat from the electrode assembly 5 to the first heat-conducting part 81 and finally to the heat exchange mechanism.

[0182] Support component 9 is disposed between the first heat-conducting part 81 and the electrode assembly 5, such as Figure 11 and Figure 12 As shown, the support component 9 is disposed on the side of the first heat-conducting part 81 facing the electrode assembly 5. One end of the support component 9 is supported by the first heat-conducting part 81, and the other end is supported by the electrode assembly 5. Gas inside the housing 4 can act on the pressure relief mechanism 41 through the support component 9 and the pressure relief hole 811. For example, the heat exchange mechanism is arranged along the first direction X and the battery cell 3, and the first heat-conducting part 81 is close to the heat exchange mechanism to facilitate the heat exchange of the electrode assembly 5 through the first heat-conducting part 81 and the heat exchange mechanism.

[0183] In some embodiments, such as Figure 10 to Figure 12 As shown, multiple electrode assemblies 5 are arranged along the second direction Y, and the first direction X and the second direction Y intersect. The heat conduction assembly 8 also includes a second heat conduction part 82, and the first heat conduction part 81 and the second heat conduction part 82 are connected. The support assembly 9 is disposed between the first heat conduction part 81 and the electrode assembly 5. There are two support assemblies 9, which are respectively disposed on both sides of the second heat conduction part 82 in the second direction Y.

[0184] In these embodiments, the support component 9 is disposed between the first heat-conducting part 81 and the electrode component 5. There are two support components 9, which are respectively disposed on both sides of the second heat-conducting part 82 in the second direction Y, so as to reduce the risk of mutual interference between the support component 9 and the second heat-conducting part 82, resulting in damage to the heat-conducting component 8.

[0185] Two support components 9 are spaced apart and are respectively disposed in a receiving space 821. Each support component 9 is supported by an electrode component 5 and a first heat-conducting part 81. A second heat-conducting part 82 extends between the two support components 9 so that the support components 9 can avoid the second heat-conducting part 82.

[0186] Optionally, the two support assemblies 9 arranged in the two accommodating spaces 821 are of the same size and shape, so as to reduce the cost of mold opening and processing of the support assembly 9.

[0187] Optionally, the second heat-conducting part 82 is smaller in the third direction Z than the support assembly 9 in the third direction Z, and the housing 4 is provided with one support assembly 9, and the support assembly 9 is provided with a through hole extending in the third direction Z, and the second heat-conducting part 82 extends out of the through hole, so as to simplify the mounting step of the support assembly 9, and the first direction X, the second direction Y and the third direction Z intersect with each other.

[0188] Optionally, the support assembly 9 is bonded to the first heat-conducting part 81 and the second heat-conducting part 82, so as to increase the contact area of the support assembly 9 and the heat-conducting assembly 8 and improve the connection reliability of the support assembly 9 and the heat-conducting assembly 8.

[0189] In some embodiments, as shown in Figure 10 and Figure 13 , the electrode assembly 5 is provided with a plurality of electrode assemblies 5, the plurality of electrode assemblies 5 are arranged in a stack along the second direction Y, the first direction X and the second direction Y intersect with each other, the heat-conducting assembly 8 further includes a second heat-conducting part 82, the first heat-conducting part 81 and the second heat-conducting part 82 are connected, the support assembly 9 is arranged between the first heat-conducting part 81 and the housing 4, and the second heat-conducting part 82 is located on the support assembly 9 in the first direction X.

[0190] In these embodiments, the support assembly 9 is arranged between the first heat-conducting part 81 and the housing 4, and the second heat-conducting part 82 is located on the support assembly 9 in the first direction X, so that a single support assembly 9 can support the first heat-conducting part 81 forming two accommodating spaces 821, thereby reducing the matching difficulty of the support assembly 9 and the heat-conducting assembly 8.

[0191] The housing 4 is provided with one support assembly 9, and the support assembly 9 can simultaneously support the electrode assemblies 5 located in the two accommodating spaces 821, thereby reducing the difficulty of arranging the support assembly 9.

[0192] Optionally, the two support assemblies 9 are arranged at intervals along the second direction Y, and each support assembly 9 is arranged between the housing 4 and the first heat-conducting part 81, and each support assembly 9 supports the electrode assembly 5 in one accommodating space 821.

[0193] Optionally, the housing 4 is provided with one support assembly 9, and the electrode assemblies 5 of the two accommodating spaces 821 are located in the support assembly 9 in the first direction X, so as to improve the support effect of the support assembly 9 on the electrode assemblies 5.

[0194] Please refer to Figure 14 , Figure 14 which is a structural schematic diagram of a support assembly of a battery monomer provided in an embodiment of the present application.

[0195] In some embodiments, as shown in Figure 10 and Figure 14 The support assembly 9 comprises an insulation portion 91 and at least two elevation portions 92 connected to each other, the insulation portion 91 is located between the electrode assembly 5 and the elevation portions 92, and each elevation portion 92 is arranged on the side of the insulation portion 91 away from the electrode assembly 5.

[0196] In these embodiments, the support assembly 9 comprises an insulation portion 91 and at least two elevation portions 92 connected to each other, the insulation portion 91 is located between the electrode assembly 5 and the elevation portions 92, and each elevation portion 92 is arranged on the side of the insulation portion 91 away from the electrode assembly 5. The insulation portion 91 is used to support the electrode assembly 5, and the cross-sectional area of the insulation portion 91 in the first direction X is greater than the total cross-sectional area of each elevation portion 92 in the first direction X, so as to increase the contact area of the support assembly 9 and the electrode assembly 5, and to make the support assembly 9 provide a stable support effect on the electrode assembly 5.

[0197] The support assembly 9 comprises an insulation portion 91 and a plurality of elevation portions 92 arranged at intervals and connected to the insulation portion 91. The insulation portion 91 is supported on the electrode assembly 5, one end of each elevation portion 92 is connected to the side of the insulation portion 91 away from the electrode assembly 5, and the other end is abutted or connected to the shell 4. At least two elevation portions 92 are arranged at intervals. The orthogonal projection of each elevation portion 92 in the first direction X is located within the insulation portion 91. The insulation portion 91 supports the electrode assembly 5, so as to increase the contact area of the electrode assembly 5 and the support assembly 9. Two or more elevation portions 92 provide a stable support effect on the insulation portion 91. The elevation portions 92 arranged at intervals provide a larger pressure relief space, so as to better buffer the pressure inside the shell 4.

[0198] For example, four elevation portions 92 are connected to the diagonal positions of the insulation portion 91, so as to improve the stability of the support assembly 9.

[0199] For example, at least two elevation portions 92 are arranged at intervals along the third direction Z, so as to stably support the insulation portion 91 and reduce the processing difficulty of the support assembly 9.

[0200] Optionally, the insulation portion 91 and the elevation portions 92 are integrally formed, so as to reduce the processing difficulty of the support assembly 9 and improve the structural strength of the support assembly 9.

[0201] Optionally, a plurality of air exchange holes are arranged through the insulation portion 91 along the first direction X, so as to facilitate the airflow through the support assembly 9.

[0202] In some embodiments, as shown in Figure 10 and Figure 14As shown, the positive projection of the pressure relief hole 811 in the first direction X is at least partially located on the insulation part 91, and the insulation part 91 is configured to be melted when the internal pressure or temperature of the battery monomer 3 reaches a threshold value.

[0203] In these embodiments, the positive projection of the pressure relief hole 811 in the first direction X is at least partially located on the insulation part 91 to increase the contact area of the insulation part 91 and the electrode assembly 5, and the insulation part 91 is configured to be melted when the internal pressure or temperature of the battery monomer 3 reaches a threshold value, so that when the battery monomer 3 is in thermal runaway, the gas in the shell 4 acts on the pressure relief mechanism 41 through the support assembly 9 and the pressure relief hole 811, thereby improving the reliability of the pressure relief mechanism 41.

[0204] For example, the melting point of the insulation part 91 is lower than the temperature when the battery monomer 3 is in thermal runaway, so that when the battery monomer 3 is in thermal runaway, the insulation part 91 is melted to avoid the insulation part 91 blocking the gas passing through the pressure relief hole 811.

[0205] For example, the material of the insulation part 91 is PP (Polypropylene; polypropylene) or PVC (Polyvinylchloride; polyvinyl chloride) or PE (polyethylene; polyethylene) or the like.

[0206] Optionally, the insulation part 91 and the pressure relief hole 811 are spaced apart in the second direction Y and / or the third direction Z to avoid the insulation part 91 blocking the pressure relief of the pressure relief hole 811. For example, the insulation parts 91 of the two support assemblies 9 are spaced apart to form a pressure relief channel, and the pressure relief hole 811 and the pressure relief channel are communicated. Alternatively, a pressure relief channel is provided through the insulation part 91, and the pressure relief hole 811 and the pressure relief channel are communicated.

[0207] In some embodiments, as shown in Figure 9 and Figure 12 As shown, the size L1 of the communication hole 822 in the first direction X and the size L2 of the support assembly 9 in the first direction X satisfy L1>L2, and at least part of the communication hole 822 can protrude from the support assembly 9 in the first direction X, so as to improve the problem that when the support assembly 9 is arranged between the first heat-conducting part 81 and the electrode assembly 5, the support assembly 9 blocks the communication hole 822, causing the gas exchange in the two accommodation spaces 821 to be blocked.

[0208] For example, the difference between L1 and L2 can be 0.3mm, 0.5mm, 1mm, 2mm or 5mm, etc.

[0209] Optionally, the size L1 of the communication hole 822 in the first direction X satisfies L1≥6mm, and when the size L1 of the communication hole 822 in the first direction X satisfies the above condition, the gas exchange rate in the two accommodation spaces 821 can be improved.

[0210] Exemplarily, the size L1 of the through hole 822 in the first direction X is 6 mm or 7 mm or 8 mm or 10 mm or 20 mm, etc.

[0211] Exemplarily, the through hole 822 is a rectangular hole, and the size of the rectangular hole in the first direction X is greater than or equal to 6 mm.

[0212] In some embodiments, as shown in Figure 10 , Figure 12 and Figure 14 , the size L2 of the support assembly 9 in the first direction X satisfies 5 mm < L2 ≤ 15 mm.

[0213] In these embodiments, when the size L2 of the support assembly 9 in the first direction X satisfies the above condition, a sufficient volume of pressure relief space is formed between the electrode assembly 5 and the shell 4, so as to improve the reliability of the battery monomer 3.

[0214] Exemplarily, the size L2 of the support assembly 9 in the first direction X is 5.1 mm or 6 mm or 7 mm or 10 mm or 15 mm, etc.

[0215] Optionally, the support assembly 9 comprises an insulation part 91 and a pad part 92, the size of the pad part 92 in the first direction X is greater than or equal to 5 mm, and the size of the insulation part 91 in the first direction X is between 1 mm and 10 mm, so as to make the pad part 92 stably support the insulation part 91. Exemplarily, the size of the insulation part 91 in the first direction X is 1 mm or 2 mm or 5 mm or 10 mm, etc.

[0216] Please refer to Figure 15 , Figure 16 , Figure 17 and Figure 18 , Figure 15 is a sectional view of a heat-conducting assembly of a battery monomer provided in an embodiment of the present application; Figure 16 is a structural schematic view of a heat-conducting assembly of a battery monomer provided in an embodiment of the present application; Figure 17 is a structural schematic view of a first heat-conducting part of a battery monomer provided in an embodiment of the present application; Figure 18 is a structural schematic view of a first heat-conducting part of a battery monomer provided in another embodiment of the present application.

[0217] In some embodiments, as shown in Figure 4 , Figure 6 , Figure 15 to Figure 18As shown, the heat-conducting assembly 8 comprises an insulating piece 85 and a heat-conducting piece 84. The insulating piece 85 forms a receiving cavity 851 at least in part, and the heat-conducting piece 84 is arranged in the receiving cavity 851. The insulating piece 85 comprises a first insulating portion 852 arranged between the shell 4 and the electrode assembly 5 along the first direction X. The heat-conducting piece 84 comprises a first heat-conducting sheet 841 heat-conductively connected to the electrode assembly 5. The first heat-conducting portion 81 is composed of the first heat-conducting sheet 841 and the first insulating portion 852. The first heat-conducting sheet 841 is provided with a first avoiding hole 8414 therethrough. At least part of the first insulating portion 852 covers the inner wall of the first avoiding hole 8414. The pressure relief hole 811 is arranged in the first insulating portion 852 and located in the first avoiding hole 8414, or the pressure relief hole 811 is arranged in the first insulating portion 852 and spaced from the receiving cavity 851.

[0218] In these embodiments, the heat-conducting assembly 8 comprises an insulating piece 85 and a heat-conducting piece 84. The insulating piece 85 forms a receiving cavity 851 at least in part, and the heat-conducting piece 84 is arranged in the receiving cavity 851. The insulating piece 85 comprises a first insulating portion 852 arranged between the shell 4 and the electrode assembly 5 along the first direction X. The heat-conducting piece 84 comprises a first heat-conducting sheet 841 heat-conductively connected to the electrode assembly 5. The first heat-conducting portion 81 is composed of the first heat-conducting sheet 841 and the first insulating portion 852. The first heat-conducting sheet 841 is provided with a first avoiding hole 8414 therethrough. At least part of the first insulating portion 852 covers the inner wall of the first avoiding hole 8414. The pressure relief hole 811 is arranged in the first insulating portion 852 and located in the first avoiding hole 8414, or the pressure relief hole 811 is arranged in the first insulating portion 852 and spaced from the receiving cavity 851. Thus, when the internal pressure of the shell 4 acts on the pressure relief mechanism 41 through the pressure relief hole 811, the electrolyte and the first heat-conducting sheet 841 are prevented from contacting each other.

[0219] For example, the insulating piece 85 can be made of PP, PI (Polyimide) or PET (Polyethylene terephthalate), etc. The heat-conducting piece 84 can be made of graphite, graphene or carbon nanotube. The heat-conducting rate of the heat-conducting piece 84 is greater than that of the shell 4.

[0220] Optionally, the heat conducting member 84 can be in a plate shape or a strip shape or a mesh shape, etc. For example, the accommodating cavity 851 is provided with a plate-shaped heat conducting member or a mesh-shaped heat conducting member or one or more strip-shaped heat conducting members arranged at intervals.

[0221] It should be noted that the heat conducting member 84 is located in the insulating member 85, and the heat conducting member 84 is covered by the insulating member 85. In the drawings, the position of the heat conducting member 84 is shown for convenience, and therefore the heat conducting member 84 is represented by the shadow on the insulating member 85.

[0222] Optionally, the insulating member 85 is provided with an accommodating cavity 851 with one end open, the heat conducting member 84 is arranged in the accommodating cavity 851 and is bonded or fused to the opening of the insulating member 85, so that the heat conducting member 84 is located in a sealed accommodating cavity 851; or the insulating member 85 is folded at both ends, the heat conducting member 84 is located between the two ends of the insulating member 85, and the two ends of the insulating member 85 are bonded or fused together, so that the heat conducting member 84 is located in a sealed accommodating cavity 851; or the insulating member 85 includes two oppositely arranged sub-insulating layers, the edges of the two sub-insulating layers are bonded or fused, so that the heat conducting member 84 is located in a sealed accommodating cavity 851.

[0223] Optionally, the side surface of the insulating member 85 facing the electrode assembly 5 is provided with a bonding layer, so that the heat conducting assembly 8 and the electrode assembly 5 are bonded and connected. For example, the bonding layer can be an insulating glue, so as to enhance the insulation performance of the heat conducting assembly 8 and the electrode assembly 5.

[0224] For example, the pressure relief hole 811 is arranged between the second end surface 522 and the pressure relief mechanism 41, the first heat conducting sheet 841 is arranged on the second end surface 522 and is in heat conducting connection with the electrode assembly 5, and the first heat conducting part 81 is composed of the first heat conducting sheet 841 and the first insulating part 852. For example, the first heat conducting sheet 841 covers the entire second end surface 522, so as to improve the heat conducting rate of the first heat conducting part 81.

[0225] The pressure relief hole 811 is arranged through the first insulating part 852, the pressure relief hole 811 and the accommodating cavity 851 are arranged at intervals, the accommodating cavity 851 is arranged in a part of the region of the first insulating part 852, the first heat conducting sheet 841 is arranged in the accommodating cavity 851, the pressure relief hole 811 is arranged through another part of the region of the first insulating part 852, the pressure relief hole 811 and the accommodating cavity 851 are not connected, so that the electrolyte cannot enter the accommodating cavity 851 and contact the first heat conducting sheet 841, and the first insulating part 852 can still keep the first heat conducting sheet 841 insulated from the electrode assembly 5.

[0226] For example, the insulating member 85 is plastic sealed to form the accommodating cavity 851, and the pressure relief hole 811 can be arranged in the plastic sealing area, or the pressure relief hole 811 is arranged on the side of the plastic sealing area away from the accommodating cavity 851.

[0227] The first heat-conducting sheet 841 is provided with a first avoiding hole 8414, and the first insulation part 852 is provided with a pressure relief hole 811. The pressure relief hole 811 is located in the first avoiding hole 8414, or the orthographic projection of the first avoiding hole 8414 in the thickness direction of the first insulation part 852 is located in the pressure relief hole 811. The gas in the shell 4 can act on the pressure relief mechanism 41 through the pressure relief hole 811. The first insulation part 852 covers the inner wall of the first avoiding hole 8414, and the first insulation part 852 is used to isolate the electrolyte and the inner wall of the first avoiding hole 8414 from contacting each other, and the first insulation part 852 insulates the electrode assembly 5 and the inner wall of the first avoiding hole 8414.

[0228] For example, the first insulation part 852 is plastic encapsulated to form a containing cavity 851, the first heat-conducting sheet 841 is contained in the containing cavity 851, and part of the first insulation part 852 is plastic encapsulated in the first avoiding hole 8414. The pressure relief hole 811 penetrates the plastic encapsulation area, and the pressure relief hole 811 and the inner wall of the first avoiding hole 8414 are spaced apart by the plastic encapsulation area.

[0229] Optionally, the first insulation part 852 is provided with at least two pressure relief holes 811, and the corresponding first heat-conducting sheet 841 is provided with at least two first avoiding holes 8414.

[0230] Please refer to Figure 19 , Figure 19 for Figure 16 the enlarged structural schematic view of B in FIG. 8.

[0231] In some embodiments, as shown in Figure 4 , Figure 15 , Figure 16 and Figure 19 , the electrode assembly 5 is provided in plurality, the plurality of electrode assemblies 5 are arranged along a second direction Y, the first direction X and the second direction Y intersect, the heat-conducting assembly 8 further includes a second heat-conducting part 82, the second heat-conducting part 82 is arranged between two adjacent electrode assemblies 5, the insulation part 85 further includes a second insulation part 853, the first insulation part 852 and the second insulation part 853 are connected, the second insulation part 853 is arranged between the adjacent electrode assemblies 5 along the second direction Y, the heat-conducting part 84 includes a second heat-conducting sheet 842, the second heat-conducting sheet 842 is arranged in the second insulation part 853, the second heat-conducting part 82 is composed of the second heat-conducting sheet 842 and the second insulation part 853, the two side surfaces of the second insulation part 853 along the second direction Y and the first insulation part 852 form two containing spaces 821 for containing the electrode assemblies 5, and the two containing spaces 821 are in communication with the pressure relief hole 811.

[0232] In the embodiments, the second insulation part 853 forms two accommodation spaces 821 for accommodating the electrode assembly 5 on both sides of the second direction Y of the second insulation part 853 and the first insulation part 852, and the two accommodation spaces 821 are both communicated with the pressure relief hole 811, so as to improve the problem that the pressure in the two accommodation spaces 821 cannot be transmitted to the pressure relief mechanism 41 due to the blocking of the first insulation part 852 when the battery monomer 3 is in thermal runaway, resulting in slow pressure relief rate of the battery monomer 3 and insufficient reliability of the battery monomer 3.

[0233] The second heat conduction part 82 is composed of the second heat conduction sheet 842 and the second insulation part 853, the second heat conduction sheet 842 is used for transmitting heat between the electrode assembly 5 and the first heat conduction sheet 841, and the second heat conduction sheet 842 is insulated from the electrode assembly 5 by the second insulation part 853.

[0234] In the above embodiments, the accommodation space 821 is formed by the first heat conduction part 81 and the second heat conduction part 82, specifically, the accommodation space 821 is formed by the first insulation part 852 and the second insulation part 853, and the electrode assembly 5 is located in the accommodation space 821 formed by the first insulation part 852 and the second insulation part 853, so as to insulate the electrode assembly 5 and the heat conduction assembly 8 from each other.

[0235] The first insulation part 852 is provided with two pressure relief holes 811 at intervals, each pressure relief hole 811 is communicated with one accommodation space 821, and the second insulation part 853 is located between the two pressure relief holes 811; or the first insulation part 852 is provided with one pressure relief hole 811, the pressure relief hole 811 extends to both sides of the second insulation part 853 along the second direction Y, and the two accommodation spaces 821 are both communicated with the pressure relief hole 811.

[0236] Please refer to Figure 20 and Figure 21 , Figure 20 is a structural schematic view of a second heat conduction part of a battery monomer provided in an embodiment of the present application; Figure 21 is a structural schematic view of a second heat conduction part of a battery monomer provided in another embodiment of the present application.

[0237] In some embodiments, as shown in Figure 4 , Figure 15 , Figure 16 , Figure 20 and Figure 21 , the second heat conduction part 82 is provided with a communication hole 822 penetrating therethrough, the second heat conduction sheet 842 is provided with a second avoiding hole 8421 penetrating therethrough, at least part of the second insulation part 853 covers the inner wall of the second avoiding hole 8421, the communication hole 822 is provided penetrating through the second insulation part 853, the communication hole 822 is located in the second avoiding hole 8421, or the communication hole 822 is provided penetrating through the second insulation part 853, and the communication hole 822 is provided at intervals with the accommodation cavity 851.

[0238] In the embodiments, the second heat-conductive part 82 is provided with a through hole 822, the second heat-conductive sheet 842 is provided with a second avoiding hole 8421, the through hole 822 is provided through the second insulating part 853 and located in the second avoiding hole 8421, so that the gas in the two accommodation spaces 821 can flow through the through hole 822, at least part of the second insulating part 853 covers the inner wall of the second avoiding hole 8421, so as to isolate the second heat-conductive sheet 842 and the electrolyte through the second insulating part 853; the through hole 822 is provided through the second insulating part 853, and the through hole 822 and the accommodation cavity 851 are spaced apart, which can make the gas in the two accommodation spaces 821 flow through the through hole 822, and avoid the contact between the electrolyte and the first heat-conductive sheet 841.

[0239] The through hole 822 is provided through the second insulating part 853, and the through hole 822 and the accommodation cavity 851 are spaced apart, the accommodation cavity 851 is arranged in part of the area of the second insulating part 853, the second heat-conductive sheet 842 is arranged in the accommodation cavity 851, the through hole 822 is provided through another part of the area of the second insulating part 853, the through hole 822 and the accommodation cavity 851 are not connected, so that the electrolyte cannot enter the accommodation cavity 851 and contact the second heat-conductive sheet 842, and the second insulating part 853 can still keep the second heat-conductive sheet 842 and the electrode assembly 5 insulated.

[0240] For example, the insulating part 85 is plastic encapsulated to form the accommodation cavity 851, and the through hole 822 can be arranged in the plastic encapsulation area, or the through hole 822 is arranged on the side of the plastic encapsulation area away from the accommodation cavity 851.

[0241] The second heat-conductive sheet 842 is provided with the second avoiding hole 8421, and the second insulating part 853 is provided with the through hole 822, the through hole 822 is located in the second avoiding hole 8421, or the orthographic projection of the second avoiding hole 8421 in the thickness direction of the second insulating part 853 is located in the through hole 822, and the gas inside the shell 4 can flow in the two accommodation spaces 821 through the through hole 822. The second insulating part 853 covers the inner wall of the second avoiding hole 8421, and the second insulating part 853 is used to isolate the electrolyte and the inner wall of the second avoiding hole 8421 from each other; and the second insulating part 853 insulates the electrode assembly 5 and the inner wall of the second avoiding hole 8421.

[0242] For example, the second insulating part 853 is plastic encapsulated to form the accommodation cavity 851, the second heat-conductive sheet 842 is accommodated in the accommodation cavity 851, part of the second insulating part 853 is plastic encapsulated in the second avoiding hole 8421, the through hole 822 is provided through the plastic encapsulation area, and the through hole 822 and the inner wall of the second avoiding hole 8421 are spaced apart through the plastic encapsulation area.

[0243] Optionally, the second insulation part 853 is provided with at least two communication holes 822. For example, the second insulation part 853 is provided with two or three or four communication holes 822.

[0244] In some embodiments, as shown in Figure 4 、 Figure 5 and Figure 16 The electrode assembly 5 includes a first end surface 521, a second end surface 522, and a side surface 523. The first end surface 521 and the second end surface 522 are oppositely arranged along a first direction X. The side surface 523 is connected between the first end surface 521 and the second end surface 522. The side surface 523 includes two first side surfaces 5231 oppositely arranged along a second direction Y and two second side surfaces 5232 oppositely arranged along a third direction Z. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The insulation part 85 further includes two third insulation parts 854. Each of the third insulation parts 854 includes a body part 8541 and a bent part 8542 connected to each other. The body parts 8541 of the two third insulation parts 854 are arranged on the two first side surfaces 5231, respectively. The bent parts 8542 of the two third insulation parts 854 are arranged on the two second side surfaces 5232, respectively. The heat conduction part 84 includes a third heat conduction sheet 843 arranged on at least one of the body part 8541 and the bent part 8542.

[0245] In these embodiments, the third insulation part 854 includes the body part 8541 and the bent part 8542 connected to each other. The body parts 8541 of the two third insulation parts 854 are arranged on the two first side surfaces 5231, respectively. The bent parts 8542 of the two third insulation parts 854 are arranged on the two second side surfaces 5232, respectively. The third heat conduction sheet 843 is arranged on at least one of the body part 8541 and the bent part 8542 to improve the heat conduction rate of the first side surface 5231 and / or the second side surface 5232 of the electrode assembly 5.

[0246] Specifically, the electrode assembly 5 includes an electrode body 52 and a tab 51. The tab 51 is connected to the electrode body 52. The first end surface 521 and the second end surface 522 are two end surfaces of the electrode body 52 along the first direction X.

[0247] The third heat conduction sheet 843 is arranged on the body part 8541. Alternatively, the third heat conduction sheet 843 is arranged on the bent part 8542. Alternatively, the third heat conduction sheet 843 is arranged on the body part 8541 and the bent part 8542 to form a third heat conduction part 83.

[0248] In the same shell 4, the insulation part 85 includes two third insulation parts 854. The oppositely arranged two third insulation parts 854 are wrapped on at least part of the outer circumferential surface of the electrode assembly 5.

[0249] The third insulation part 854 comprises a body part 8541 and a bent part 8542 connected to each other, the body part 8541 and the bent part 8542 are integrally formed to improve the structural strength of the third insulation part 854, there is a folding line between the body part 8541 and the bent part 8542, the body part 8541 covers the first side surface 5231, the bent part 8542 is bent along the folding line and covers the second side surface 5232, or the body part 8541 and the bent part 8542 are respectively prepared, and the body part 8541 and the bent part 8542 are connected by bonding or welding.

[0250] The third insulation part 854 comprises a body part 8541 and a bent part 8542 connected to the body part 8541 at one end in the third direction Z, the body part 8541 covers one first side surface 5231 of the electrode assembly 5, one end of the bent part 8542 is connected to the body part 8541, and the other end of the bent part 8542 extends towards the body part 8541 of the other third insulation part 854 in the second direction Y, the bent part 8542 is connected to two body parts 8541, or the bent part 8542 and the body part 8541 are arranged separately, and are connected by a Mylar film therebetween.

[0251] Alternatively, the third insulation part 854 comprises a body part 8541 and a bent part 8542 connected to the body part 8541 at both ends in the third direction Z, the body part 8541 covers the first side surface 5231 of the electrode assembly 5, the bent parts 8542 of the two oppositely arranged third insulation parts 854 oppositely extend in the second direction Y and are connected to each other, or the bent parts 8542 of the two oppositely arranged third insulation parts 854 oppositely extend in the second direction Y, and the two bent parts 8542 are connected by a Mylar film.

[0252] Alternatively, the body part 8541 covers the first side surface 5231 of the electrode assembly 5, and the bent part 8542 covers the second side surface 5232 of the electrode assembly 5, so that the first insulation part 852 can reliably insulate the electrode assembly 5 and the shell 4.

[0253] Alternatively, the heat-conducting member 84 is arranged on the entire body part 8541 or the bent part 8542; or a plurality of heat-conducting members 84 are arranged separately on the body part 8541 or the bent part 8542.

[0254] Alternatively, a plurality of electrode assemblies 5 are arranged, the body part 8541 is arranged between the shell 4 and the first side surface 5231 closest to the shell 4, and the bent part 8542 is arranged on one or more second side surfaces 5232.

[0255] In some embodiments, as Figure 4 , Figure 5 , Figure 15 and Figure 16As shown, the body part 8541 is connected with a bending part 8542 on each side in the third direction Z, and the two bending parts 8542 of the two third insulation parts 854 on the same side of the electrode assembly 5 extend towards each other in the second direction Y.

[0256] In these embodiments, the body part 8541 is connected with a bending part 8542 on each side in the third direction Z, and the two bending parts 8542 of the two third insulation parts 854 on the same side of the electrode assembly 5 extend towards each other in the second direction Y, so that the spliced part of the two bending parts 8542 is located on the second side surface 5232, and the larger first side surface 5231 can be provided with a larger third heat conduction sheet 843 to improve the heat conduction capacity of the heat conduction assembly 8.

[0257] Alternatively, the two bending parts 8542 of the two third insulation parts 854 extend towards each other in the second direction Y and are spaced apart or abut each other in the second direction Y, so that the body part 8541 can cover the entire first side surface 5231, and the heat conduction member 84 can cover the entire first side surface 5231 to improve the heat conduction efficiency of the heat conduction assembly 8; or the two bending parts 8542 of the two first insulation parts 852 extend towards each other in the second direction Y and overlap each other, so that the overlapping part of the bending parts 8542 in the third direction Z does not increase the size of the battery monomer 3 in the second direction Y.

[0258] For example, the bending parts 8542 of the two third insulation parts 854 are bent and connected with each other. The insulation member 85 is connected by two sub-insulation layers, and the two sub-insulation layers are connected to form a containing cavity 851 in the body part 8541. Each bending part 8542 includes two sub-insulation layers. For the convenience of understanding, part of the sub-insulation layer is folded, and part of the sub-insulation layer is unfolded.

[0259] Alternatively, the two bending parts 8542 connected on both sides of the body part 8541 are the same in size and shape, so as to reduce the processing difficulty of the third insulation part 854. The size and shape of the bending part 8542 can be designed by itself. For example, the bending part 8542 is rectangular.

[0260] In some embodiments, as shown in Figure 4 and Figure 15 The thickness D1 of the heat conduction member 84 satisfies 40 μm≤D1≤180 μm.

[0261] In these embodiments, when the above conditions are met, the problem of the battery monomer 3 being too large in size and the energy density being reduced due to the heat conduction member 84 being too thick can be improved, and the problem of the heat conduction member 84 being easily damaged due to the heat conduction member 84 being too thin can be improved.

[0262] Exemplarily, the thickness D3 of the heat-conducting component 8 is 40 μm or 50 μm or 110 μm or 180 μm, etc.

[0263] In some embodiments, as shown in Figure 4 and Figure 15 The insulating member 85 includes polyethylene or polypropylene or polyimide or polyester resin.

[0264] In these embodiments, the insulating member 85 includes polyethylene or polypropylene or polyimide or polyester resin to improve the insulation reliability of the insulating member 85.

[0265] Optionally, the insulating member 85 should have the characteristics of insulation and high-temperature resistance, so that the insulating member 85 can be used to insulate the heat-conducting member 84 and the electrode assembly 5, and reduce the risk of melting damage of the insulating member 85 under high-temperature conditions.

[0266] In some embodiments, as shown in Figure 4 and Figure 15 The heat-conducting member 84 includes graphite or graphene or carbon nanotubes.

[0267] In these embodiments, graphite is generally composed of parallel arranged layered carbon atoms, showing a planar sheet shape. Graphene is generally a two-dimensional crystal composed of carbon atoms with only one side atomic thickness, belonging to the shape of fibers. Carbon nanotubes are generally tubular structures formed by rolling one or more graphite layers. The material of the heat-conducting member 84 includes graphite or graphene or carbon nanotubes, which improves the heat-conducting performance of the heat-conducting member 84 through graphite or graphene or carbon nanotube heat-conducting materials.

[0268] Optionally, the material of the heat-conducting member 84 is supercrystalline graphite, which has a larger grain size than ordinary graphite, and the thermal conductivity is significantly improved compared with ordinary graphite, so that the heat-conducting member 84 has better heat-conducting capacity.

[0269] Optionally, the heat-conducting member 84 adopts graphite heat-conducting technology, which is a heat-conducting technology based on graphite materials and micro-porous structures. Its principle is to quickly transfer heat to the heat-conducting sheet through the high-efficiency heat-conducting performance of graphite materials, and then quickly dissipate heat to the external environment through the micro-porous structure, so as to achieve the effect of heat exchange.

[0270] In some embodiments, as shown in Figure 4 and Figure 15 The thermal conductivity k of the heat-conducting member 84 satisfies k≥500 W / (m·K).

[0271] In these embodiments, the heat-conducting member 84 satisfies the above condition, so that the heat-conducting component 8 has sufficient heat-conducting performance to conduct the heat of the electrode main body 52.

[0272] Optionally, the thermal conductivity k of the heat-conducting member 84 satisfies 500 W / (m·K)≤k≤1600 W / (m·K), and exemplarily, the thermal conductivity of the heat-conducting member 84 is 500 W / (m·K), or 550 W / (m·K), or 1050 W / (m·K), or 1550 W / (m·K), or 1600 W / (m·K), etc.

[0273] Optionally, the thermal conductivity k of the heat-conducting member 84 satisfies k≥1000 W / (m·K).

[0274] Optionally, the density of the heat-conducting member 84 is 2.1±0.05 g / cm 3 , the insulation resistance is greater than 1 GΩ, the withstand voltage strength is 5400 V, and the bending resistance is greater than 10000 times.

[0275] In a second aspect, the embodiments of the present application provide a battery device, which comprises the battery monomer of any of the embodiments of the first aspect.

[0276] In a third aspect, the embodiments of the present application provide a power consumption device, which comprises the battery device of the embodiments of the second aspect.

[0277] In some embodiments, as Figure 1 to Figure 21As shown, the battery monomer 3 comprises a shell 4, an electrode assembly 5, a heat conduction assembly 8 and a support assembly 9, the shell 4 is provided with a pressure relief mechanism 41 for relieving the pressure in the shell 4; the electrode assembly 5 is located in the shell 4, the electrode assembly 5 comprises an electrode body 52 and a tab 51, the electrode body 52 comprises a first end face 521 and a second end face 522 oppositely arranged in the first direction X, the tab 51 is connected to the electrode body 52 and protrudes from the first end face 521, the electrode assembly 5 is provided with a plurality of electrode assemblies 5, the plurality of electrode assemblies 5 are arranged side by side along the second direction Y, the first direction X and the second direction Y intersect; the heat conduction assembly 8 comprises a first heat conduction part 81 and a second heat conduction part 82, the first heat conduction part 81 and the second end face 522 are in thermal connection, wherein the first heat conduction part 81 is arranged between the second end face 522 and the pressure relief mechanism 41, the first heat conduction part 81 is provided with a pressure relief hole 811 penetrating the first heat conduction part 81 along the first direction X, along the first direction X, the orthographic projection of the pressure relief mechanism 41 and the orthographic projection of the pressure relief hole 811 at least partially coincide, the first heat conduction part 81 and the second heat conduction part 82 are connected, the second heat conduction part 82 is arranged between the two adjacent electrode assemblies 5, the second heat conduction part 82 forms two accommodation spaces 821 for accommodating the electrode assemblies 5 on the two side surfaces thereof in the second direction Y and the first heat conduction part 81, the two accommodation spaces 821 are both in communication with the pressure relief hole 811, the second heat conduction part 82 is provided with a communication hole 822 penetrating thereon, the communication hole 822 is in communication with the pressure relief hole 811, the support assembly 9 is arranged between the shell 4 and the second end face 522 to form a pressure relief space between the second end face 522 and the shell 4, the support assembly 9 is arranged between the first heat conduction part 81 and the shell 4, or the support assembly 9 is arranged between the first heat conduction part 81 and the electrode assembly 5, the support assembly 9 comprises an insulating part 91 and at least two heightening parts 92 connected to each other, the insulating part 91 is located between the electrode assembly 5 and the heightening part 92, each heightening part 92 is arranged on the side of the insulating part 91 away from the electrode assembly 5, the insulating part 91 and the pressure relief hole 811 at least partially coincide, the insulating part 91 is configured to melt when the pressure relief mechanism 41 is activated, the size L1 of the communication hole 822 in the first direction X satisfies L1≥6mm, the size L2 of the support assembly 9 in the first direction X satisfies 5mm

[0278] In the scheme of the embodiment of the application, the battery monomer 3 comprises a shell 4, an electrode assembly 5 and a heat conduction assembly 8, the shell 4 is provided with a pressure relief mechanism 41 for relieving the pressure in the shell 4, the electrode assembly 5 is arranged in the shell 4, the heat conduction assembly 8 comprises a first heat conduction part 81, the first heat conduction part 81 is in heat conduction connection with the electrode assembly 5, and the rate of heat exchange between the electrode main body 52 and the external environment is improved, the first heat conduction part 81 is arranged between the electrode assembly 5 and the pressure relief mechanism 41, the first heat conduction part 81 is provided with a pressure relief hole 811 penetrating through the first heat conduction part 81 along the first direction X, along the first direction X, the orthographic projection of the pressure relief mechanism 41 and the orthographic projection of the pressure relief hole 811 at least partially coincide, so that at least part of the pressure relief mechanism 41 is exposed by the pressure relief hole 811, so that when the battery monomer 3 is in thermal runaway, the internal pressure of the shell 4 can act on the pressure relief mechanism 41 through the pressure relief hole 811, so as to smoothly start the pressure relief mechanism 41, so as to improve the reliability of the pressure relief mechanism 41 of the battery monomer 3.

[0279] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application, and they should be covered in the scope of the claims and the specification of the application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The battery monomer comprises: a shell provided with a pressure relief mechanism; an electrode assembly located in the shell; a heat conduction assembly comprising a first heat conduction part, the first heat conduction part and the electrode assembly are in heat conduction connection, wherein the first heat conduction part is arranged between the electrode assembly and the pressure relief mechanism along a first direction, the first heat conduction part is provided with a pressure relief hole penetrating through the first heat conduction part along the first direction, and the orthogonal projection of the pressure relief mechanism and the orthogonal projection of the pressure relief hole at least partially overlap along the first direction.

2. The battery cell of claim 1, wherein, The orthogonal projection of the pressure relief hole is completely located within the orthogonal projection range of the pressure relief mechanism along the first direction.

3. The battery cell of claim 1, wherein, The electrode assembly is provided with a plurality of electrode assemblies arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, the second heat conduction part is arranged between two adjacent electrode assemblies, the two sides of the second heat conduction part along the second direction and the first heat conduction part form two accommodation spaces for accommodating the electrode assemblies, and the two accommodation spaces are in communication with the pressure relief hole.

4. The battery cell of claim 3, wherein, The second heat conduction part is provided with a communication hole penetrating through along the second direction.

5. The battery cell of claim 4, wherein, The communication hole is arranged at one end of the second heat conduction part close to the first heat conduction part.

6. The battery cell of claim 5, wherein, The communication hole and the pressure relief hole are in communication.

7. The battery cell of any one of claims 1 to 6, wherein, The battery monomer further comprises a support assembly arranged between the shell and the electrode assembly to form a pressure relief space between the electrode assembly and the shell.

8. The battery cell of claim 7, wherein, The support assembly is arranged between the first heat conduction part and the shell, or the support assembly is arranged between the first heat conduction part and the electrode assembly.

9. The battery cell of claim 8, wherein, The electrode assembly is provided with a plurality of electrode assemblies arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, The support assembly is arranged between the first heat conduction part and the electrode assembly, and the number of the support assembly is two, the two support assemblies are arranged on both sides of the second heat conduction part along the second direction.

10. The battery cell of claim 8, wherein, The electrode assembly is provided with a plurality of electrode assemblies arranged along a second direction, the first direction and the second direction intersect, the heat conduction assembly further comprises a second heat conduction part, the first heat conduction part and the second heat conduction part are connected, The support assembly is arranged between the first heat conduction part and the shell, and the orthogonal projection of the second heat conduction part along the first direction is located on the support assembly.

11. The battery cell of claim 7, wherein, The support assembly comprises an insulation part and at least two heightening parts connected with each other, the insulation part is located between the electrode assembly and the heightening part, and each heightening part is arranged on one side of the insulation part away from the electrode assembly.

12. The battery cell of claim 11, wherein, The orthogonal projection of the pressure relief hole along the first direction is at least partially located on the insulation part, and the insulation part is configured to be melted when the internal pressure or temperature of the battery monomer reaches a threshold value.

13. The battery cell of claim 7, wherein, The size L2 of the support assembly along the first direction satisfies 5mm 14. The battery cell of claim 1, wherein, The heat-conducting assembly comprises an insulating member and a heat-conducting member, the insulating member forms a containing cavity in at least a partial region, the heat-conducting member is arranged in the containing cavity, the insulating member comprises a first insulating part, the first insulating part is arranged between the shell and the electrode assembly along the first direction, the heat-conducting member comprises a first heat-conducting sheet, the first heat-conducting sheet is heat-conducting connected to the electrode assembly, the first heat-conducting part is composed of the first heat-conducting sheet and the first insulating part, wherein the first heat-conducting sheet is provided with a first avoiding hole penetrating therethrough, at least a partial region of the first insulating part covers an inner wall of the first avoiding hole, the pressure relief hole is provided in the first insulating part, and the pressure relief hole is located in the first avoiding hole, or the pressure relief hole is provided in the first insulating part, and the pressure relief hole is arranged in a spaced manner with the containing cavity.

15. The battery cell of claim 14, wherein, The electrode assembly is arranged in a plurality of forms, the plurality of electrode assemblies are arranged in a second direction, the first direction and the second direction intersect with each other, the heat-conducting assembly further comprises a second heat-conducting part, and the second heat-conducting part is arranged between two adjacent electrode assemblies, the insulating member further comprises a second insulating part, the first insulating part and the second insulating part are connected, the second insulating part is arranged between the adjacent electrode assemblies along the second direction, the heat-conducting member comprises a second heat-conducting sheet, the second heat-conducting sheet is arranged in the second insulating part, the second heat-conducting part is composed of the second heat-conducting sheet and the second insulating part, and two side surfaces of the second insulating part along the second direction and the first insulating part form two containing spaces for containing the electrode assemblies, and the two containing spaces are communicated with the pressure relief hole.

16. The battery cell of claim 15, wherein, The second heat-conducting part is provided with a communicating hole penetrating therethrough, the second heat-conducting sheet is provided with a second avoiding hole penetrating therethrough, at least a partial region of the second insulating part covers an inner wall of the second avoiding hole, the communicating hole is provided in the second insulating part, and the communicating hole is located in the second avoiding hole, or the communicating hole is provided in the second insulating part, and the communicating hole is arranged in a spaced manner with the containing cavity.

17. The battery cell of claim 15, wherein, The electrode assembly comprises a first end surface, a second end surface and a side surface, the first end surface and the second end surface are oppositely arranged along the first direction, the side surface is connected between the first end surface and the second end surface, the side surface comprises two first side surfaces oppositely arranged in the second direction and two second side surfaces oppositely arranged in a third direction, the first direction, the second direction and the third direction intersect with each other, the insulating member further comprises two third insulating parts, the third insulating part comprises a body part and a bending part connected with each other, the body parts of the two third insulating parts are arranged at the two first side surfaces respectively, and the bending parts of the two third insulating parts are arranged at the two second side surfaces respectively, the heat-conducting member comprises a third heat-conducting sheet, and the third heat-conducting sheet is arranged in at least one of the body part and the bending part.

18. The battery cell of claim 17, wherein, The body part is connected with one bending part on each side in the third direction, and the two bending parts of the two third insulating parts located on the same side of the electrode assembly extend towards each other in the second direction.

19. The battery cell of any one of claims 14 to 18, wherein, The thickness D1 of the heat-conducting member satisfies 40 μm ≤ D1 ≤ 180 μm.

20. The battery cell of any one of claims 14 to 18, wherein, The insulating member comprises polyethylene or polypropylene or polyimide or polyester resin.

21. The battery cell of any one of claims 14 to 18, wherein, The heat-conducting member comprises graphite or graphene or carbon nanotube.

22. The battery cell of any one of claims 14 to 18, wherein, The heat conductivity k of the heat-conducting member satisfies k ≥ 500 W / (m·K).

23. A battery device, characterized by The battery cell comprises any one of the battery cells according to claims 1-22.

24. An electrical device, comprising: The battery device comprises the battery cell according to claim 23.

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