Battery monomer, battery device and electric equipment

Abstract

The invention relates to a battery monomer, a battery device and electric equipment. The battery monomer comprises a shell, an end cover assembly, an electrode assembly and a heat conduction piece, an accommodating cavity with an opening in one end is formed in the shell; the end cover assembly comprises an end cover covering the opening; the electrode assembly is arranged in the containing cavity and comprises two end faces arranged oppositely and a side face connected with the two end faces. The heat conduction piece is arranged in the containing cavity, arranged on at least part of the side face and connected with the end cover. According to the invention, the problem that the performance and the service life of the battery monomer are adversely affected due to too high or too low internal temperature of the battery monomer can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to battery cells, battery devices and electrical equipment. Background Technology

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

[0003] However, in actual operation, excessively high or low internal temperatures of a battery cell can adversely affect its lifespan and performance. Summary of the Invention

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

[0005] In a first aspect, this application proposes a battery cell, including a housing, an end cap assembly, an electrode assembly, and a heat-conducting element; the housing forms a receiving cavity with an opening at one end; the end cap assembly includes an end cap covering the opening; the electrode assembly is disposed within the receiving cavity, and the electrode assembly includes two oppositely disposed end faces and a side face connecting the two end faces; the heat-conducting element is disposed within the receiving cavity, the heat-conducting element is disposed on at least a portion of the side face, and the heat-conducting element is connected to the end cap.

[0006] In this embodiment, the battery cell includes a housing, an end cap assembly, an electrode assembly, and a heat-conducting component. The electrode assembly is located within a receiving cavity. The housing and end cap together provide housing and protection for the electrode assembly. By providing a heat-conducting component on at least a portion of the side of the electrode assembly, heat from the point of thermal contact between the electrode assembly and the heat-conducting component can be conducted through the heat-conducting component, improving the overall temperature uniformity of the electrode assembly. Furthermore, by connecting the heat-conducting component to the end cap, heat from the electrode assembly can be conducted to the end cap for heat dissipation, increasing the rate of heat exchange between the electrode body and the external environment. This balances the internal temperature of the battery cell and mitigates the adverse effects on the performance and lifespan of the battery cell caused by excessively high or low internal temperatures.

[0007] In some embodiments, the heat-conducting element is disposed around the side.

[0008] In these embodiments, by providing a heat-conducting element around the outer periphery of the electrode assembly, the contact area between the heat-conducting element and the side can be increased, further improving the overall temperature uniformity of the electrode assembly.

[0009] In some embodiments, the heat-conducting element is provided with a connecting portion extending toward the end cap. The connecting portion includes an extension section and a bending section. The extension section is connected between the bending section and the heat-conducting element, and the side of the bending section away from the heat-conducting element is connected to the side of the end cap toward the receiving cavity.

[0010] In these embodiments, by providing an extension section, the bending section can be brought closer to the end cap, and the side of the bending section away from the heat conductor can be connected to the side surface of the end cap facing the receiving cavity, thereby increasing the contact area between the bending section and the end cap and thus improving the heat conduction efficiency of the heat conductor.

[0011] In some embodiments, the bent section extends from the extension section in a direction away from the sidewall of the housing.

[0012] In these embodiments, by extending the bending section from the extension section in a direction away from the sidewall of the housing, the contact area between the bending section and the end cap can be increased, thereby further improving the thermal conductivity of the heat-conducting component.

[0013] In some embodiments, the end cap assembly further includes an insulating member disposed on the side of the end cap facing the electrode assembly, the insulating member having a clearance opening for accommodating a bent section.

[0014] In these embodiments, by creating clearance openings in the insulating component to accommodate the bent section that fits snugly against the end cap, and by providing space for the bent section, the internal structure of the battery cell can be made more compact, resulting in higher space utilization.

[0015] In some embodiments, there are two connectors, which are spaced apart and disposed on the same side of the heat-conducting component.

[0016] In these embodiments, the two connecting parts are located on the same side of the heat-conducting component, which can avoid the insulating component together, making the installation simpler. Furthermore, by separating the two connecting parts, the connecting parts can avoid interfering with the insulating component, making it easier to connect to the end cap.

[0017] In some embodiments, the electrode assembly includes two first side surfaces disposed opposite to each other in a first direction, and the heat-conducting element includes two first heat-conducting sheets disposed opposite to each other in a first direction, each first heat-conducting sheet being disposed on each of the first side surfaces; at least one first heat-conducting sheet is provided with a connecting portion.

[0018] In these embodiments, the side of the electrode body includes two first side surfaces arranged opposite to each other in a first direction. It is understood that the area occupied by the first side surfaces arranged opposite to each other in the thickness direction is relatively large compared to the other side surfaces. The two first heat-conducting sheets are arranged one-to-one with the two first side surfaces, and both can conduct heat through the connecting part and the end cap, which helps to increase the contact area between the heat-conducting element and the electrode body, so as to enhance the heat conduction rate of the heat-conducting element.

[0019] In some embodiments, the electrode assembly further includes two second side surfaces disposed opposite to each other in a second direction, the two first side surfaces and the two second side surfaces being alternately connected in sequence, and the area of ​​the first side surface being larger than the area of ​​the second side surface.

[0020] In these embodiments, the first side is the large surface of the electrode assembly, and a larger area of ​​the first heat-conducting sheet can be provided on the first side to improve the heat conduction rate of the first heat-conducting sheet to the electrode body.

[0021] In some embodiments, the thermal conductive element further includes two second thermal conductive sheets, with the two first thermal conductive sheets and the two second thermal conductive sheets alternately connected to enclose the electrode assembly.

[0022] In these embodiments, the first heat-conducting sheet is connected to the second heat-conducting sheet, so that the heat-conducting element is disposed around the outer periphery of the electrode body, thereby further improving the heat conduction rate of the heat-conducting element.

[0023] In some embodiments, a single battery cell includes two or more electrode assemblies and two or more heat-conducting components, with the heat-conducting components corresponding to the electrode assemblies one-to-one.

[0024] In these embodiments, by providing multiple electrode assemblies within a single battery cell, the capacity of a single battery cell can be increased. Furthermore, by providing a separate heat-conducting component for each battery cell, the temperature uniformity within the battery cell can be improved, increasing the rate of heat exchange between the electrode cell and the external environment. This balances the internal temperature of the battery cell and further mitigates the adverse effects on the performance and lifespan of the battery cell caused by excessively high or low internal temperatures.

[0025] In some embodiments, a heat-conducting element is wound around a side surface, and a gap is formed between the two ends of the heat-conducting element wound around the side surface, the gap being located on the side of the electrode assembly corresponding to the heat-conducting element facing the adjacent electrode assembly.

[0026] In these embodiments, the heat-conducting element consists of a strip wrapped around the outer periphery of the electrode assembly, with a gap between the two ends. This gap is located on the side between two adjacent electrode assemblies, which on the one hand allows for expansion space for the electrode assembly, and on the other hand reduces the risk of overlap between the electrode assembly and the housing.

[0027] In some embodiments, an electrode terminal is provided on the end cap, and a first opening is formed in the heat-conducting element. The electrode terminal is electrically connected to the tab of the electrode assembly through the first opening.

[0028] In these embodiments, the heat-conducting element has a first opening to expose the tabs of the electrode terminals or electrode assembly, allowing the electrode terminals to be directly electrically connected to the tabs or electrically connected via an adapter.

[0029] In some embodiments, the heat-conducting component includes an end-face heat-conducting sheet and two first heat-conducting portions disposed opposite each other along a first direction. The first heat-conducting portions are disposed between the electrode assembly and the housing, and the end-face heat-conducting sheet is connected between the two first heat-conducting portions and connected to the end cap.

[0030] In these embodiments, the heat at the point of thermal contact between the electrode assembly and the first heat-conducting part can be sequentially conducted through the first heat-conducting part and the end-face heat-conducting sheet to the end cap for heat dissipation. This increases the rate of heat exchange between the electrode body and the external environment, thereby balancing the internal temperature of the battery cell and mitigating the adverse effects on the performance and lifespan of the battery cell caused by excessively high or low internal temperatures. The end-face heat-conducting sheet can be fitted to the end cap, thereby increasing the contact area between the heat-conducting component and the end cap, and further improving the thermal conductivity of the heat-conducting component.

[0031] In some embodiments, the number of electrode assemblies is at least two sets, and the at least two sets of electrode assemblies are stacked along a first direction. The heat-conducting component further includes a second heat-conducting part, which is disposed between two adjacent sets of electrode assemblies, and the end face heat-conducting sheet is connected to the second heat-conducting part.

[0032] In these embodiments, by providing a second heat-conducting part between two sets of adjacent electrode assemblies, the heat that is difficult to dissipate between the two adjacent electrode assemblies can be conducted to the outside through the second heat-conducting part, the end face heat-conducting sheet, and the end cap in sequence, so that the internal temperature of the battery cell is better balanced, and the heat conduction efficiency of the heat-conducting component is increased at the same time.

[0033] In some embodiments, the second heat-conducting portion includes a second main body and two second connecting segments. The second main body is spaced apart from the end face heat-conducting sheet, and the second connecting segments are connected between the second main body and the end face heat-conducting sheet. The two second connecting segments are spaced apart along a second direction, and a clearance groove is formed between the two second connecting segments. The second direction and the first direction are perpendicular to each other.

[0034] In these embodiments, by providing clearance grooves, interference between the second heat-conducting part and structures such as the tabs, electrode terminals, and adapter components can be reduced.

[0035] In some embodiments, the battery cell further includes a bracket disposed between the end face heat-conducting sheet and the electrode assembly, and an installation space is formed between the bracket and the end face heat-conducting sheet.

[0036] In these embodiments, the bracket can replace the lower plastic in the prior art, and can also serve to support and protect the electrode assembly, as well as provide installation space for the tabs. Furthermore, in this embodiment, the bracket is disposed inside the heat-conducting component, which, unlike the lower plastic which avoids the connection between the heat-conducting component and the end cap, provides better protection for the tabs. This also allows the heat-conducting component to completely enclose both the electrode body and the tabs of the electrode assembly within its interior.

[0037] In some embodiments, the bracket includes a first support portion and a second support portion, the first support portion and the second support portion are respectively disposed on both sides of the second heat-conducting portion along a first direction, and a gap is formed between the first support portion and the second support portion for the second heat-conducting portion to pass through.

[0038] In these embodiments, the gap between the first support and the second support is used to avoid the second heat-conducting part, so that the second heat-conducting part can be connected to the end face heat-conducting sheet.

[0039] In some embodiments, the bracket includes a support section and two raised sections. The support section is spaced apart from the end face heat-conducting sheet. The raised sections extend from the support section toward the end cap, and the two raised sections are spaced apart along a second direction. The end face heat-conducting sheet, the support section, and the two raised sections enclose at least a portion of the installation space. The second direction and the first direction are perpendicular to each other.

[0040] In these embodiments, the support section can be used to abut against the end face of the electrode assembly and provide support for the electrode assembly, and the raised section is disposed between the support section and the end face heat-conducting sheet, which can both support the support section and form an installation space between the support section and the end face heat-conducting sheet.

[0041] In some embodiments, the end face heat-conducting sheet and the two first heat-conducting parts enclose a covering space, and multiple sets of electrode assemblies are located within the covering space.

[0042] In these embodiments, by setting end face heat-conducting sheets and two first heat-conducting parts to form a covering space, the full covering of multiple sets of electrode assemblies can be achieved. This eliminates the need for setting insulating sheets and hot-melting processes on the outside of the original electrode assemblies. While ensuring the performance of the original electrode assemblies, the structure and processes are simplified, and the heat inside the electrode assemblies can be connected to the housing and end cap for rapid heat dissipation.

[0043] In some embodiments, the end face heat-conducting sheet is fitted to the end cap; the end face heat-conducting sheet has an electrode post hole, and / or, the end face heat-conducting sheet has a pressure relief hole.

[0044] In these embodiments, the end-face heat-conducting sheet is fitted to the end cap, allowing the heat received by the end-face heat-conducting sheet to be directly conducted to the end cap. The end-face heat-conducting sheet forms an electrode post hole, allowing the electrode terminals of the end cap to extend into the encapsulation space and electrically connect to the electrode tabs. The end-face heat-conducting sheet also forms a pressure relief hole, facilitating the timely discharge of gas generated inside the electrode assembly to the pressure relief mechanism, thereby improving the safety of the battery cell.

[0045] In some embodiments, an electrode terminal is provided on the end cap, and one end of the electrode terminal passes through the electrode post hole and is electrically connected to the electrode tab of the electrode assembly.

[0046] In these embodiments, by passing one end of the electrode terminal through the electrode post hole into the encapsulation space, the tabs can be positioned within the encapsulation space formed by the heat-conducting component, reducing the risk of electrical conductivity between the tabs and the housing.

[0047] In some embodiments, the heat-conducting element includes a heat-conducting sheet and an insulating film covering the heat-conducting sheet, wherein the thermal conductivity k of the heat-conducting sheet satisfies k≥500W / (m·K).

[0048] In these embodiments, the insulating film can serve to support and protect the heat-conducting sheet. When the thermal conductivity k of the heat-conducting sheet meets the above conditions, the heat-conducting sheet has sufficient thermal conductivity to conduct heat from the electrode body.

[0049] In some embodiments, the heat-conducting sheet is made of graphite, graphene, or carbon nanotubes.

[0050] In these embodiments, the thermal conductivity of the heat-conducting sheet is improved by using graphite, graphene, or carbon nanotube thermal conductive materials.

[0051] Secondly, this application provides a battery device comprising a battery cell according to any of the first aspects of the above embodiments.

[0052] Thirdly, this application provides an electrical device that includes a battery cell from any of the first aspects of the above-described embodiments; or includes a battery device from the second aspect of the above-described embodiments, wherein the battery device is used to provide electrical energy.

[0053] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0054] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0055] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0056] Figure 2 This is a schematic diagram of the structure of a battery device provided in an embodiment of this application;

[0057] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of this application;

[0058] Figure 4 This is a schematic diagram of the structure of a battery cell provided in an embodiment of this application;

[0059] Figure 5 yes Figure 4Sectional view at point AA;

[0060] Figure 6 yes Figure 5 Enlarged view of section B;

[0061] Figure 7 This is one of the three-dimensional structural schematic diagrams of the heat-conducting component in a battery cell provided in an embodiment of this application;

[0062] Figure 8 This is a three-dimensional structural schematic diagram of the battery cell end cap assembly provided in an embodiment of this application;

[0063] Figure 9 This is a schematic diagram of the structure of a battery cell after removing the outer casing, according to an embodiment of this application;

[0064] Figure 10 yes Figure 9 Sectional view at CC;

[0065] Figure 11 yes Figure 10 Enlarged view of section D;

[0066] Figure 12 This is one of the schematic diagrams of the unfolded structure of a single battery cell provided in an embodiment of this application;

[0067] Figure 13 This is a second schematic diagram of the unfolded structure of a single battery cell provided in an embodiment of this application;

[0068] Figure 14 This is a second three-dimensional structural schematic diagram of the heat-conducting component in a battery cell provided in an embodiment of this application;

[0069] Figure 15 This is a three-dimensional structural diagram of the support structure in a battery cell provided in an embodiment of this application;

[0070] Figure 16 This is the third schematic diagram of the unfolded structure of a battery cell provided in one embodiment of this application (with the support removed).

[0071] The accompanying drawings may not be drawn to scale.

[0072] Explanation of reference numerals in the attached figures:

[0073] 1000, vehicles;

[0074] 100. Battery assembly; 110. Controller; 120. Motor;

[0075] 200. Battery module;

[0076] 300. Enclosure; 301. First enclosure; 302. Second enclosure;

[0077] 10. Battery cells;

[0078] 1. Shell; 11. Receiving cavity;

[0079] 2. End cap assembly; 21. End cap; 211. Electrode terminal; 212. Adapter component; 22. Insulator; 221. Clearance opening;

[0080] 3. Electrode assembly; 31. Electrode body; 32. Tab;

[0081] 4. Heat-conducting component; 40. Connecting part; 401. Extension section; 402. Bending section; 41. First heat-conducting plate; 42. Second heat-conducting plate; 43. First opening; 45. End face heat-conducting plate; 451. Pole post hole; 452. Pressure relief hole; 46. First heat-conducting part; 47. Second heat-conducting part; 471. Second main body part; 472. Second connecting section; 473. Clearance groove; 48. Enclosing space; 400. Gap;

[0082] 5. Bracket; 50. Installation space; 51. First support section; 52. Second support section; 53. Gap; 501. Support section; 502. Elevation section; 503. Auxiliary elevation section;

[0083] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0084] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0085] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0086] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0087] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0088] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0089] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0090] In this application, "multiple" means two or more (including two).

[0091] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery device applications, market demand is also constantly increasing.

[0092] Excessive temperature differences between the inside and outside of a battery cell during use can lead to a decrease in the cell's performance and lifespan.

[0093] The reason for the above problems is that during the operation of a battery cell, the electrode assembly undergoes an electrochemical reaction and generates heat. This heat needs to be exchanged between the casing and the external environment. Due to the limited thermal conductivity of the casing, the internal temperature of the battery cell cannot be quickly conducted to the outside, causing the internal temperature to accumulate and rise. The electrode assembly is prone to lithium plating due to excessive temperature. In low-temperature environments, it is also difficult for the external environment to heat the electrode assembly, resulting in a decrease in capacity and pulse performance of the battery cell due to low temperature, thus affecting the performance of the battery cell.

[0094] To address the aforementioned issues, this application provides a battery cell comprising a housing, an end cap assembly, an electrode assembly, and a heat-conducting component. The electrode assembly is located within a housing cavity. The housing and end cap together provide housing and protection for the electrode assembly. By providing a heat-conducting component surrounding the electrode assembly, heat at the point of thermal contact between the electrode assembly and the heat-conducting component can be conducted through the heat-conducting component, improving the overall temperature uniformity of the electrode assembly. Furthermore, by connecting the heat-conducting component to the end cap, heat from the electrode assembly can be conducted to the end cap for heat dissipation, increasing the rate of heat exchange between the electrode body and the external environment. This balances the internal temperature of the battery cell and mitigates the adverse effects on the battery cell's performance and lifespan caused by excessively high or low internal temperatures.

[0095] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical equipment using battery devices.

[0096] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0097] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0098] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application embodiment is not limited to this. The battery cell can be cylindrical, flat, cuboid, or other shapes, and this application embodiment is not limited to this either.

[0099] The battery device mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery device mentioned in this application may include a battery module or a battery pack. A battery pack generally includes a housing for encapsulating one or more battery cells. The housing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0100] A single battery cell includes electrode components and an electrolyte. The electrode components include a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode components. The positive electrode includes a positive current collector and a positive active material layer, the latter coated on the surface of the current collector. The current collector includes a positive current-collecting section and a positive electrode tab connected to it. The current-collecting section is coated with the positive active material layer, while the tab is not. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material layer includes the positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer being coated on the surface of the negative current collector. The negative current collector includes a negative current collection section and a negative electrode tab connected to the negative current collection section. The negative current collection section is coated with the negative active material layer, while the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0101] It should be understood that the technical solutions described in the embodiments of this application are not limited to the battery devices and electrical equipment described above, but can also be applied to all battery devices including housings and electrical equipment using battery devices. However, for the sake of brevity, the following embodiments are all illustrated using electric vehicles as examples.

[0102] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 110 and a motor 120. The controller 110 is used to control the battery to supply power to the motor 120, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0103] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0104] Figure 2 A schematic diagram of the structure of a battery device according to an embodiment of this application is shown.

[0105] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 10, which are connected in series, parallel, or mixed connections via a busbar.

[0106] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of battery cells 10.

[0107] As an example, the battery cell assembly can be a battery module 200, which is formed by arranging and fixing multiple battery cells 10 into a single module. As an example, the battery module 200 can be formed by bundling multiple battery cells 10 together with cable ties.

[0108] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 300 and one or more battery cell assemblies housed in the housing 300.

[0109] As an example, the battery cell assembly can be a battery module 200, which can be housed in the housing 300 by fixing the battery module 200 in the housing 300.

[0110] As an example, the battery cell assembly can also be housed in the housing 300 by directly fixing multiple battery cells 10 to the housing 300.

[0111] As an example, the housing 300 may include a first housing 301 and a second housing 302. The first housing 301 and the second housing 302 are fastened together to form a closed space inside the housing 300 to house the battery cell assembly. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing 301 may be a top cover or a bottom plate.

[0112] As an example, the housing 300 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 300 forms an enclosed space to accommodate the battery cell assembly.

[0113] In some embodiments, the housing 300 may be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 300 may be at least a portion of the floor of the vehicle 1000, or a portion of the housing 300 may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0114] Figure 3 A schematic diagram of the structure of a battery module according to an embodiment of this application is shown.

[0115] In some embodiments, such as Figure 2 and Figure 3 As shown, there are multiple battery cells 10. These multiple battery cells 10 are first connected in series, parallel, or in a mixed manner to form a battery module 200. The multiple battery modules 200 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing 300.

[0116] Multiple battery cells 10 in the battery module 200 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 10 in the battery module 200.

[0117] In this application, the battery cell 10 may include lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, etc., and the embodiments of this application are not limited to this.

[0118] A battery cell 10 refers to the smallest unit that makes up a battery. A battery cell 10 includes an end cap assembly 2, a housing 1, and an electrode assembly 3.

[0119] Electrode assembly 3 is the component in the battery cell 10 where electrochemical reactions occur. The casing 1 may contain one or more electrode assemblies 3. Electrode assembly 3 is mainly formed by winding or stacking electrode sheets, which are divided into positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the electrode body 31, while the portions of the positive and negative electrode sheets without active material each constitute a tab 32. The positive and negative tabs can be located together at one end of the electrode body 31 or separately at both ends of the electrode body 31. During the charging and discharging process of the battery cell 10, the positive and negative active materials react with the electrolyte, and the tabs 32 connect to the electrode terminals 211 to form a current loop.

[0120] The electrode assembly 3 can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0121] In some embodiments, electrode assembly 3 is a wound structure. The positive electrode and negative electrode are wound into a wound structure.

[0122] In some embodiments, the electrode assembly 3 is a stacked structure. As an example, multiple positive and negative electrodes can be provided, with multiple positive and multiple negative electrodes stacked alternately. Multiple spacers can be provided and respectively provided between any adjacent positive or negative electrodes. Alternatively, the spacers can be provided continuously and provided between any adjacent positive or negative electrodes by folding.

[0123] In some embodiments, the electrode assembly 3 may be cylindrical, flat, or polygonal, etc.

[0124] In some embodiments, the electrode assembly 3 is provided with tabs 32, which can conduct current from the electrode assembly 3. The tabs 32 include a positive tab and a negative tab.

[0125] The battery cell 10 may include a housing 1. The housing 1 is an assembly used to cooperate with the end cap assembly 2 to form the internal environment of the battery cell 10, wherein the formed internal environment can accommodate the electrode assembly 3, electrolyte (not shown in the figure), and other components. The housing 1 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing 1), or an aluminum-plastic film, etc. In some embodiments, the housing 1 can be a sealed structure or a non-sealed structure. As an example, when the housing 1 is a non-sealed structure, the housing 1 serves to protect the electrode assembly 3, and a sealing bag is also included between the housing 1 and the electrode assembly 3. The sealing bag is used to encapsulate the electrode assembly 3 and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film. When the housing 1 is a sealed structure, it is used to encapsulate the electrode assembly 3 and electrolyte, etc.

[0126] As an example, the battery cell 10 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0127] The housing 1 and the end cap assembly 2 can be independent components. One or more openings can be provided on the housing 1, and one or more end cap assemblies 2 can close the openings to form the internal environment of the battery cell 10. Optionally, the end cap assembly 2 and the housing 1 can also be integrated. Optionally, the end cap assembly 2 and the housing 1 can form a common connection surface before other components are inserted into the housing, and the end cap assembly 2 closes the housing 1 when it is necessary to encapsulate the interior of the housing 1.

[0128] In some embodiments, the electrode terminal 211 can be disposed on the end cap assembly 2 or on the housing 1, and the electrode terminal 211 is electrically connected to the tab 32. The electrode terminal 211 can be directly connected to the tab 32 or indirectly connected to the tab 32 through the adapter 212.

[0129] Please see Figures 4 to 8 , Figure 4 This is a schematic diagram of the structure of a battery cell provided in an embodiment of this application; Figure 5 yes Figure 4 Sectional view at point AA; Figure 6 yes Figure 5 Enlarged view of section B; Figure 7 This is one of the three-dimensional structural schematic diagrams of the heat-conducting component in a battery cell provided in an embodiment of this application; Figure 8 This is a three-dimensional structural diagram of the battery cell end cap assembly provided in an embodiment of this application.

[0130] Reference Figures 4 to 8 In a first aspect, this application proposes a battery cell 10, which includes a housing 1, an end cap assembly 2, an electrode assembly 3, and a heat-conducting element 4. The housing 1 forms a receiving cavity 11 with an opening at one end. The end cap assembly 2 includes an end cap 21 covering the opening. The electrode assembly 3 is disposed in the receiving cavity 11 and includes two end faces disposed opposite to each other and a side face connecting the two end faces. The heat-conducting element 4 is disposed in the receiving cavity 11, and the heat-conducting element 4 is disposed on at least a portion of the side face, and the heat-conducting element 4 is connected to the end cap 21.

[0131] The heat-conducting component 4 is a component with good heat conduction capacity. The heat-conducting component 4 is disposed on at least part of the side surface. This can be understood as follows: the electrode assembly 3 includes two oppositely arranged end faces and a side surface connecting the two end faces. The heat-conducting component 4 can be thermally connected to only part of the side surface or to all of the side surface. The heat-conducting component 4 can be a closed ring or a semi-enclosed ring. The heat-conducting component 4 can conduct heat from the electrode assembly 3. This can be achieved by directly attaching or abutting the side surface of the electrode assembly 3; or by the heat-conducting component 4 being a plating layer disposed on the side surface; or by the heat-conducting component 4 and the side surface being spaced apart, with the heat-conducting component 4 connected to the side surface through a heat-conducting medium, which can be air, metal, or thermally conductive adhesive, etc.

[0132] In this embodiment, the battery cell 10 includes a housing 1, an end cap assembly 2, an electrode assembly 3, and a heat-conducting element 4. The electrode assembly 3 is located within a receiving cavity 11. The housing 1 and the end cap 21 together provide housing and protection for the electrode assembly 3. By providing the heat-conducting element 4 on at least a portion of the side of the electrode assembly 3, heat at the point of thermal contact between the electrode assembly 3 and the heat-conducting element 4 can be conducted through the heat-conducting element 4, improving the overall temperature uniformity of the electrode assembly 3. Furthermore, by connecting the heat-conducting element 4 to the end cap 21, heat from the electrode assembly 3 can be conducted to the end cap 21 for heat dissipation, increasing the rate of heat exchange between the electrode body 31 and the external environment. This balances the internal temperature of the battery cell 10 and mitigates the adverse effects on the performance and lifespan of the battery cell 10 caused by excessively high or low internal temperatures.

[0133] Optionally, the heat-conducting component 4 may also include an insulating material, thereby enabling insulation between the electrode assembly 3 and the housing 1 by covering the electrode assembly 3.

[0134] In addition, besides being connected to the end cap 21, the heat-conducting component 4 can also directly or indirectly contact the inner wall surface of the housing 1. That is, in this embodiment, in addition to conducting the heat of the electrode assembly 3 to the outside through the large surface of the housing 1, the heat-conducting component 4 can also be directly connected to the end cap 21 to conduct the heat to the outside through the end cap 21, and can also conduct the heat to the housing 1 through the end cap 21, thereby increasing the heat conduction efficiency of the electrode assembly 3 and reducing safety problems caused by the excessive temperature of the electrode assembly 3.

[0135] During the operation of the battery cell 10, the heat generated by the electrode assembly 3 can be transferred to the external environment through the heat-conducting component 4, which can improve the problem of the electrode assembly 3 being damaged due to excessive temperature; or in a low-temperature environment, the heat-conducting component 4 can conduct external heat to the electrode assembly 3 to heat the electrode assembly 3.

[0136] In some embodiments, the heat-conducting element 4 is disposed around the side.

[0137] The heat-conducting element 4 is arranged around the side, which can be understood as: the heat-conducting element 4 is arranged around the outer periphery of the side of the electrode assembly 3, that is, the heat-conducting element 4 is arranged at least around the side of the electrode assembly 3.

[0138] In these embodiments, by providing the heat-conducting element 4 around the outer periphery of the electrode assembly 3, the contact area between the heat-conducting element 4 and the side can be increased, further improving the overall temperature uniformity of the electrode assembly.

[0139] Reference Figure 6 and Figure 7 In some embodiments, the heat-conducting element 4 is provided with a connecting portion 40 extending toward the end cap 21. The connecting portion 40 includes an extension section 401 and a bending section 402. The extension section 401 is connected between the bending section 402 and the heat-conducting element 4. The side of the bending section 402 away from the heat-conducting element 4 is connected to the side of the end cap 21 toward the receiving cavity 11.

[0140] Typically, the electrode body 31 of the electrode assembly 3 is a certain distance from the end cap 21 to provide space for connecting the tab 32 to the electrode terminal 211 provided on the end cap 21. By providing the connecting part 40, the heat-conducting member 4, which is in direct thermal contact with the electrode body 31, can conduct heat through the connecting part 40 to the end cap 21.

[0141] In these embodiments, by providing the extension section 401, the bending section 402 can be brought closer to the end cap 21, and the side of the bending section 402 away from the heat conductor 4 can be connected to the side surface of the end cap 21 facing the receiving cavity 11, thereby increasing the contact area between the bending section 402 and the end cap 21, and thus improving the heat conduction efficiency of the heat conductor 4.

[0142] In some embodiments, the bent section 402 extends from the extension section 401 in a direction away from the sidewall of the housing 1, or in other words, the bent section 402 extends from the extension section 401 toward the interior of the receiving cavity 11.

[0143] The extension section 401 can extend from the heat-conducting part toward the end cover 21 along the third direction Z. In order to avoid other components such as the insulating part 22 between the end cover 21 and the electrode body 31, the extension section 401 can be provided on the side of the heat-conducting part 4 near the inner wall of the housing 1. After the bending section 402 extends from the extension section 401 toward the inside of the receiving cavity 11 along the first direction X, it can increase its contact area with the end cover 21.

[0144] Optionally, the first direction X is the thickness direction of the electrode assembly 3, and the third direction Z is the height direction of the electrode assembly 3.

[0145] In these embodiments, by extending the bending section 402 from the extension section 401 in a direction away from the side wall of the housing 1, the contact area between the bending section 402 and the end cap 21 can be increased, thereby further improving the thermal conductivity of the heat-conducting component 4.

[0146] Reference Figures 6 to 8 In some embodiments, the end cap assembly 2 further includes an insulating member 22 disposed on the side of the end cap 21 facing the electrode assembly 3, and the insulating member 22 is formed with a clearance opening 221 for accommodating the bent section 402.

[0147] The insulating element 22 can be used to separate the end cap 21 from the electrode assembly 3. One of its functions is to protect the electrode assembly 3 and prevent short circuits that may occur when the electrode assembly 3 is electrically connected to the metal housing 1 (such as an aluminum housing). Furthermore, the insulating element 22 also functions as a support bracket 5, positioned between the electrode assembly 3 and the end cap 21. When the end cap 21 is pressed against the electrode assembly 3, the insulating element 22 can also provide support and cushioning. For example, the insulating element 22 can be made of plastic.

[0148] In these embodiments, by providing a clearance opening 221 on the insulating member 22 to accommodate the bent section 402 that fits against the end cap 21, and by providing space for the bent section 402, the internal structure of the battery cell 10 can be arranged more compactly and the space utilization rate can be higher.

[0149] In some embodiments, there are two connecting portions 40, which are spaced apart and disposed on the same side of the heat-conducting member 4.

[0150] In these embodiments, the two connecting portions 40 are located on the same side of the heat-conducting member 4, which can avoid the insulating member 22 together, making the arrangement simpler. Furthermore, by spacing the two connecting portions 40 apart, the connecting portions 40 can avoid interfering with the insulating member 22, making it easier to connect to the end cap 21.

[0151] For example, the connecting part 40 and the end cap 21 can be bonded or heat-fused together.

[0152] Optionally, the battery device 100 includes a water cooling mechanism, and the housing 1 and / or end cap 21 of the battery cell 10 are thermally connected to the water cooling mechanism.

[0153] For example, the water cooling mechanism can be located on the shoulder of the battery module 200, that is, the water cooling mechanism is located outside the end cover 21 and is thermally connected to the end cover 21, so that the heat conduction component 4 can conduct heat through the end cover 21 and the water cooling mechanism.

[0154] In some embodiments, the electrode assembly 3 includes two first side surfaces disposed opposite to each other in the first direction X, and the heat-conducting member 4 includes two first heat-conducting sheets 41 disposed opposite to each other in the first direction X, with each first heat-conducting sheet 41 disposed on each of the first side surfaces; at least one first heat-conducting sheet 41 is provided with a connecting portion 40.

[0155] Since the heat-conducting element 4 is arranged around the outer periphery of the electrode assembly 3, the various parts of the heat-conducting element 4 are assembled into an interconnected whole. The two first heat-conducting sheets 41 can be directly connected or indirectly connected through other parts of the heat-conducting element 4. Even if only one first heat-conducting sheet 41 is provided with a connecting part 40, the two first heat-conducting sheets 41 can achieve heat conduction with the end cap 21 through the connecting part 40.

[0156] In these embodiments, the side of the electrode body 31 includes two first side surfaces arranged opposite each other in the first direction X. It can be understood that the area occupied by the first side surfaces arranged opposite each other in the thickness direction is relatively large compared to the other side surfaces. The two first heat-conducting sheets 41 are arranged one-to-one with the two first side surfaces, and both can conduct heat to the end cap 21 through the connecting part 40, which helps to increase the contact area between the heat-conducting element 4 and the electrode body 31, so as to enhance the heat conduction rate of the heat-conducting element 4.

[0157] In some embodiments, the electrode assembly 3 further includes two second side surfaces disposed opposite to each other in the second direction Y, the two first side surfaces and the two second side surfaces being alternately connected in sequence, and the area of ​​the first side surface being larger than the area of ​​the second side surface.

[0158] Optionally, the second direction Y refers to the length direction of the electrode assembly 3. The first direction X, the second direction Y, and the third direction Z are all perpendicular to each other.

[0159] The electrode body 31 includes a first side and a second side with different areas. For example, the cross-section of the electrode body 31 perpendicular to the third direction Z is rectangular or elliptical.

[0160] In these embodiments, the first side is the larger surface of the electrode assembly 3, and a larger area of ​​the first heat-conducting sheet 41 can be provided on the first side to improve the heat conduction rate of the first heat-conducting sheet 41 to the electrode body 31. The specific areas of the first and second sides can be designed independently.

[0161] Optionally, each first heat-conducting part 46 covers the entire surface of each first side to improve the heat conduction rate of the first heat-conducting part 46.

[0162] Optionally, in the battery device 100, a heat exchange mechanism can be provided corresponding to the first side. The first side is thermally connected to the heat exchange mechanism, and the heat-conducting element 4 can conduct heat between the heat exchange mechanism and the electrode assembly 3. The heat exchange mechanism can introduce or export heat to the heat-conducting element 4. For example, the heat exchange mechanism can be provided on a water-cooled plate or a phase change heat sink or a cavity containing a heat exchange medium on the outer surface of the battery cell 10.

[0163] In some embodiments, the heat-conducting element 4 further includes two second heat-conducting sheets 42, and the two first heat-conducting sheets 41 and the two second heat-conducting sheets 42 are alternately connected to enclose the electrode assembly 3.

[0164] Each second heat-conducting plate 42 is disposed between each second side and the inner wall of the housing 1. The two second heat-conducting plates 42 are disposed opposite each other in the second direction Y, and conduct heat through thermal connection with the second side.

[0165] In these embodiments, the first heat-conducting sheet 41 is connected by the second heat-conducting sheet 42, so that the heat-conducting element 4 is disposed around the outer periphery of the electrode body 31, thereby further improving the heat conduction rate of the heat-conducting element 4.

[0166] In this embodiment, the heat-conducting element 4 forms a ring around the electrode assembly 3. Firstly, it serves to wrap and secure the assembly; secondly, it protects the electrode assembly 3 from puncture; and thirdly, it allows for faster heat transfer to the large aluminum shell and end cap 21 for heat dissipation. By providing a connecting portion 40 on the heat-conducting element 4, which is then attached to the end cap 21, the heat dissipation efficiency of the electrode assembly 3 is increased. Simultaneously, the tabs 32 are positioned on the outside to prevent them from contacting the housing 1 for electrical conduction.

[0167] Optionally, the heat-conducting component 4 can be integrally molded to reduce the seams of the heat-conducting component 4 and improve the structural stability of the heat-conducting component 4.

[0168] In some embodiments, the battery cell 10 includes two or more electrode assemblies 3 and two or more heat-conducting elements 4, with the heat-conducting elements 4 corresponding to the electrode assemblies 3 one-to-one.

[0169] Each heat-conducting component 4 covers each electrode assembly 3, and each heat-conducting component 4 may be provided with a connecting part 40 connected to the end cover 21, so that each heat-conducting component 4 can individually conduct heat from each electrode assembly 3 to the end cover 21 through the connecting part 40.

[0170] In these embodiments, by providing multiple electrode assemblies 3 within the battery cell 10, the capacity of a single battery cell 10 can be increased. Furthermore, by providing a separate heat-conducting component 4 for each battery cell 10, the temperature uniformity inside the battery cell 10 can be improved, and the rate of heat exchange between the inside of the electrode cell and the external environment can be increased to balance the internal temperature of the battery cell 10. This further mitigates the problem of adverse effects on the performance and lifespan of the battery cell 10 caused by excessively high or low internal temperatures.

[0171] In some embodiments, refer to Figure 7 The heat-conducting element 4 is wrapped around the side of the electrode assembly 3, and a gap 400 is formed between the two ends of the heat-conducting element 4 wrapped around the side. The gap 400 is located on the side of the electrode assembly 3 that is corresponding to the heat-conducting element 4 and faces the adjacent electrode assembly 3.

[0172] The heat-conducting element 4 can be in contact with or disconnected from each other after enclosing the electrode assembly 3, and can also be spaced apart from each other. The heat-conducting element 4 is a closed ring or a semi-enclosed ring, so that the heat-conducting element 4 has a gap 400. The width of the gap 400 can be zero, close to zero or greater than zero, and the specific size can be designed by the user.

[0173] In these embodiments, the heat-conducting element 4 is a long strip wrapped around the outer periphery of the electrode assembly 3, and a gap 400 is formed at both ends. This gap 400 is located on the side between two adjacent electrode assemblies 3, which can reserve expansion space for the electrode assembly 3 on the one hand, and reduce the risk of overlap between the electrode assembly 3 and the housing 11 on the other hand.

[0174] For example, refer to Figure 7 The gap 400 and the connecting part 40 are disposed opposite to each other on two different sides of the heat-conducting member 4 at intervals in the first direction X, so that the connecting part 40 and the insulating member 23 can be fitted together.

[0175] In some embodiments, an electrode terminal 211 is provided on the end cap 21, and a first opening 43 is formed in the heat-conducting element 4. The electrode terminal 211 is electrically connected to the tab 32 of the electrode assembly 3 through the first opening 43.

[0176] Electrode terminals 211 are used to connect electrode assembly 3 and external circuitry, thereby enabling interaction between battery cell 10 and the external environment, such as charging and discharging. There can be two electrode terminals 211, which serve as the positive and negative terminals of battery cell 10, respectively, for connection to the external circuitry.

[0177] In these embodiments, the heat-conducting element 4 has a first opening 43 to expose the electrode terminal 211 or the tab 32 of the electrode assembly 3, so that the electrode terminal 211 can be directly electrically connected to the tab 32 or electrically connected through the adapter 212.

[0178] Please see Figures 9 to 11 , Figure 9 This is a schematic diagram of the structure of the end cap and heat-conducting component of a battery cell provided in an embodiment of this application; Figure 10 yes Figure 9 Sectional view at CC; Figure 11 yes Figure 10 Enlarged view of section D.

[0179] Reference Figures 9 to 11 In some embodiments, the heat-conducting component 4 includes an end face heat-conducting sheet 45 and two first heat-conducting parts 46 disposed opposite each other along the first direction X. The first heat-conducting parts 46 are disposed between the electrode assembly 3 and the housing 1. The end face heat-conducting sheet 45 is connected between the two first heat-conducting parts 46 and connected to the end cap 21.

[0180] The first heat-conducting part 46 being disposed between the electrode assembly 3 and the housing 1 can be understood as follows: if there is one electrode assembly 3, the two first heat-conducting parts 46 are respectively disposed on both sides of the electrode assembly 3 in the first direction X, so that the heat on both sides of the large surface of the electrode assembly 3 can be conducted to the end cap 21 through the heat-conducting element 4; if there are multiple electrode assemblies 3 stacked along the first direction X, the two first heat-conducting parts 46 are respectively disposed on both sides of the multiple electrode assemblies 3 as a whole in the first direction X, that is, the first heat-conducting parts 46 can all make heat-conducting contact with the side of the electrode assembly 3 and the inner wall of the housing 1.

[0181] In these embodiments, the heat from the position where the electrode assembly 3 is in thermal contact with the first heat-conducting part 46 can be conducted sequentially through the first heat-conducting part 46 and the end-face heat-conducting sheet 45 to the end cap 21 for heat dissipation. This increases the rate of heat exchange between the electrode body 31 and the external environment, thereby balancing the internal temperature of the battery cell 10 and mitigating the adverse effects on the performance and lifespan of the battery cell 10 caused by excessively high or low internal temperatures. The end-face heat-conducting sheet 45 can be fitted to the end cap 21, thereby increasing the contact area between the heat-conducting component 4 and the end cap 21, and further improving the thermal conductivity of the heat-conducting component 4.

[0182] In some embodiments, the number of electrode assemblies 3 is at least two sets, and the at least two sets of electrode assemblies 3 are stacked along the first direction X. The heat-conducting component 4 further includes a second heat-conducting part 47, which is disposed between two adjacent sets of electrode assemblies 3, and the end face heat-conducting sheet 45 is connected to the second heat-conducting part 47.

[0183] The second heat-conducting part 47 extends from the end face heat-conducting plate 45 in the third direction Z toward the receiving cavity 11. The side of the two adjacent electrode assemblies 3 is less likely to dissipate heat or conduct to the outside compared to the side of the inner wall of the housing 1.

[0184] In these embodiments, by providing a second heat-conducting part 47 between two sets of adjacent electrode components 3, the heat that is difficult to dissipate between the two adjacent electrode components 3 can be conducted to the outside through the second heat-conducting part 47, the end face heat-conducting sheet 45, and the end cap 21 in sequence, so that the internal temperature of the battery cell 10 is better balanced, and the heat conduction efficiency of the heat-conducting component 4 is increased at the same time.

[0185] Reference Figure 12 , Figure 12 This is one of the schematic diagrams of the unfolded structure of a battery cell provided in an embodiment of this application.

[0186] In some embodiments, the second heat-conducting portion 47 includes a second main body portion 471 and two second connecting segments 472. The second main body portion 471 is spaced apart from the end face heat-conducting sheet 45. The second connecting segments 472 are connected between the second main body portion 471 and the end face heat-conducting sheet 45. The two second connecting segments 472 are spaced apart along the second direction Y, and a clearance groove 473 is formed between the two second connecting segments 472. The second direction Y and the first direction X are perpendicular to each other.

[0187] In these embodiments, the second connecting segment 472 extends from the second main body portion 471 toward the end cap 21 (extending in the third direction Z), such that a gap is formed between the second main body portion 471 and the end face heat-conducting plate 45, and a relief groove 473 is formed to reduce interference between the second heat-conducting portion 47 and structures such as the tab 32, electrode terminal 211, and adapter member 212. Figure 16 As shown.

[0188] Please see Figures 11 to 13 , Figure 13 This is the second schematic diagram of the unfolded structure of a battery cell provided in one embodiment of this application.

[0189] like Figures 11 to 13 As shown, in some embodiments, the battery cell 10 further includes a bracket 5, which is disposed between the end face heat-conducting sheet 45 and the electrode assembly 3, and an installation space 50 is formed between the bracket 5 and the end face heat-conducting sheet 45.

[0190] The bracket 5 can support the electrode body 31 and forms an installation space 50 with the end face heat-conducting plate 45, which allows the electrode tab 32 of the electrode assembly 3 to extend into the installation space 50 and be electrically connected to the electrode terminal 211.

[0191] In these embodiments, the bracket 5 can replace the lower plastic in the prior art, and can also serve to support and protect the electrode assembly 3, as well as provide the mounting space 50 for the tab 32. Furthermore, in this embodiment, the bracket 5 is disposed inside the heat-conducting element 4. Unlike the lower plastic which avoids the connection position between the heat-conducting element 4 and the end cap 21, the heat-conducting element 4 provides better protection for the tab 32. This also allows the heat-conducting element 4 to completely enclose both the electrode body 31 and the tab 32 of the electrode assembly 3 within its interior.

[0192] In some embodiments, the bracket 5 includes a first support portion 51 and a second support portion 52, the first support portion 51 and the second support portion 52 are respectively disposed on both sides of the second heat-conducting portion 47 along the first direction X, and a gap 53 is formed between the first support portion 51 and the second support portion 52 for the second heat-conducting portion 47 to pass through.

[0193] The number of gaps 53 can be adapted to the number of second heat-conducting parts 47. For example, if there are two electrode assemblies 3, then only one second heat-conducting part 47 can be set, and the same applies to the gaps 53.

[0194] In these embodiments, the gap 53 between the first support portion 51 and the second support portion 52 is used to avoid the second heat-conducting portion 47 so that the second heat-conducting portion 47 can be connected to the end face heat-conducting sheet 45.

[0195] In some embodiments, in conjunction with reference Figures 12 to 15 The bracket 5 includes a support section 501 and two raised sections 502. The support section 501 is spaced apart from the end face heat-conducting plate 45. The raised sections 502 extend from the support section 501 toward the end cover 21, and the two raised sections 502 are spaced apart along the second direction Y. The end face heat-conducting plate 45, the support section 501 and the two raised sections 502 enclose at least a portion of the installation space 50. The second direction Y and the first direction X are perpendicular to each other.

[0196] In these embodiments, the support section 501 can be used to abut against the end face of the electrode assembly 3 and provide support for the electrode assembly 3. The raised section 502 is disposed between the support section 501 and the end face heat-conducting sheet 45, which can both support the support section 501 and form an installation space 50 between the support section 501 and the end face heat-conducting sheet 45.

[0197] Optionally, an auxiliary shim section 503 can be provided in the middle of the support section 501 to provide auxiliary support for the support section 501 and prevent the middle of the support section 501 from collapsing towards the end cover 21. The auxiliary shim section 503 is located between the two shim sections 502. The end of the auxiliary shim section 503 away from the support section 501 can be used to abut against the end cover 21 (through the pressure relief hole 452 opened in the end face heat-conducting plate 45) or the end face heat-conducting plate 45.

[0198] In some embodiments, either the first support portion 51 or the second support portion 52 may include the structure of the support section 501 and the raised section 502 described above. Therefore, it also has its beneficial effects, which will not be elaborated further here.

[0199] In some embodiments, the end face heat-conducting sheet 45 and the two first heat-conducting parts 46 enclose a covering space 48, and multiple sets of electrode assemblies 3 are located within the covering space 48.

[0200] The two first heat-conducting parts 46 can be folded to completely cover the outer periphery of the multiple sets of electrode assemblies 3. That is, in addition to covering the sides of the multiple sets of electrode assemblies 3, they can also cover the end face of the multiple sets of electrode assemblies 3 away from the end cover 21. The end face heat-conducting sheet 45 covers the end face of the multiple sets of electrode assemblies 3 near the end cover 21 and the tab 32.

[0201] In these embodiments, by setting the end face heat-conducting sheet 45 and the two first heat-conducting parts 46 to form a covering space 48, the multiple sets of electrode components 3 are fully covered. This eliminates the need for the original electrode components 3 to have an insulating sheet and to undergo heat fusion. While ensuring the performance of the original electrode components 3, the structure and process are simplified. Furthermore, the heat inside the electrode components 3 can be connected to the housing 1 and the end cover 21 for rapid heat dissipation.

[0202] Figure 14 This is a second three-dimensional structural schematic diagram of the heat-conducting component in a battery cell provided in an embodiment of this application.

[0203] like Figure 11 and Figure 14 As shown, in some embodiments, the end face heat-conducting sheet 45 is fitted to the end cap 21; the end face heat-conducting sheet 45 is formed with an electrode post hole 451, and / or, the end face heat-conducting sheet 45 is formed with a pressure relief hole 452.

[0204] The end cap 21 may be provided with electrode terminals 211 and a pressure relief mechanism, which is used to release internal gas from the battery cell 10. As an example, the internal pressure or temperature of the battery cell 10 is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 10 reaches the predetermined threshold, the pressure relief mechanism is activated or a weak structure in the pressure relief mechanism is broken, thereby forming an opening or channel for the release of internal pressure or temperature. This threshold design varies depending on design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 10.

[0205] The term "actuation" as used in this application refers to the pressure relief mechanism being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 10. The actions of the pressure relief mechanism may include, but are not limited to: movement of components within the pressure relief mechanism to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism, etc. When the pressure relief mechanism is actuated, the high-temperature, high-pressure substances inside the battery cell 10 are discharged outwards from the actuated portion as waste. This method enables the battery cell 10 to release pressure and temperature under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0206] The emissions from the battery cell 10 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0207] In these embodiments, the end-face heat-conducting sheet 45 is fitted to the end cap 21, allowing the heat received by the end-face heat-conducting sheet 45 to be directly conducted to the end cap 21. The end-face heat-conducting sheet 45 forms an electrode post hole 451, allowing the electrode terminals 211 of the end cap 21 to pass through and extend into the covering space 48 to electrically connect with the tabs 32. The end-face heat-conducting sheet 45 forms a pressure relief hole 452, which facilitates the timely discharge of gas generated inside the electrode assembly 3 to the pressure relief mechanism, improving the safety of the battery cell 10.

[0208] In some embodiments, an electrode terminal 211 is provided on the end cap 21, and one end of the electrode terminal 211 passes through the electrode post hole 451 and is electrically connected to the electrode tab 32 of the electrode assembly 3.

[0209] Electrode terminal 211 can be directly electrically connected to electrode tab 32 or electrically connected via adapter 212. When adapter 212 is provided, such as... Figure 16 As shown, the tab 32 can be spaced apart from the electrode terminal 211 along the second direction. The two ends of the adapter 212 are connected to the tab 32 and the electrode terminal 211 respectively. By providing the adapter 212, the structure within the battery cell 10 can be more compact, occupying less space. The adapter 212 can be entirely located within the mounting space 50, that is, the adapter 212 is located between the bracket 5 and the end-face heat-conducting plate 45, while the tab 32 extends from the electrode body 31 into the mounting space 50. For example, the tab 32 can pass through the gap between the bracket 5 and the first heat-conducting part 46 on either side of the first direction X.

[0210] In these embodiments, by passing one end of the electrode terminal 211 through the electrode post hole 451 into the enclosure space 48, the tabs 32 can all be disposed within the enclosure space 48 formed by the heat-conducting element 4, reducing the risk of electrical conduction between the tabs 32 and the housing 1.

[0211] In some embodiments, the heat-conducting element 4 includes a heat-conducting sheet and an insulating film covering the heat-conducting sheet, wherein the thermal conductivity k of the heat-conducting sheet satisfies k≥500W / (m·K).

[0212] In these embodiments, the insulating film serves to support and protect the heat-conducting sheet. When the thermal conductivity k of the heat-conducting sheet meets the above conditions, it ensures sufficient thermal conductivity to conduct heat from the electrode body 31. Optionally, the thermal conductivity k of the heat-conducting sheet satisfies 500 W / (m·K) ≤ k ≤ 1600 W / (m·K). For example, the thermal conductivity of the heat-conducting sheet is 500 W / (m·K), 550 W / (m·K), 1050 W / (m·K), 1550 W / (m·K), or 1600 W / (m·K), etc. For example, the insulating film can be made of PP or PI (polyimide) or PET (polyethylene terephthalate), etc.

[0213] In some embodiments, the heat-conducting sheet is made of graphite, graphene, or carbon nanotubes.

[0214] In these embodiments, graphite is typically composed of parallel layers of carbon atoms, exhibiting a planar sheet-like morphology. Graphene is typically a two-dimensional crystal composed of carbon atoms, with only one atom's thickness on one side, and has a fibrous shape. Carbon nanotubes are typically tubular structures formed by rolling up one or more layers of graphite. The thermal conductive sheet is made of graphite, graphene, or carbon nanotubes, and the thermal conductivity of the thermal conductive sheet is improved by using graphite, graphene, or carbon nanotube thermal conductive materials.

[0215] Optionally, the heatsink is made of supercrystalline graphite, which has a larger grain size than ordinary graphite and a significantly improved thermal conductivity, thus giving the heatsink better thermal conductivity.

[0216] Optionally, the heatsink uses graphite thermal conductivity technology, which is a thermal conductivity technology based on graphite materials and microporous structures. Its principle is to utilize the high thermal conductivity of graphite materials to quickly transfer heat to the heatsink, and then dissipate the heat to the external environment rapidly through the microporous structure, thereby achieving a heat exchange effect.

[0217] Secondly, embodiments of this application provide a battery device 100, including a battery cell 10 from any of the embodiments of the first aspect described above.

[0218] Thirdly, embodiments of this application provide an electrical device including a battery cell 10 from any of the embodiments of the first aspect described above, or a battery device 100 from the embodiments of the second aspect described above. The battery cell 10 or the battery device 100 is used to provide electrical energy to the electrical device.

[0219] The electrical equipment can be any of the aforementioned devices or systems that utilize battery devices 100.

[0220] According to some embodiments of this application, refer to Figures 4 to 8 This application provides a battery cell 10, which includes a housing 1, an end cap assembly 2, an electrode assembly 3, and a heat-conducting element 4. The housing 1 forms a receiving cavity 11 with an opening at one end. The end cap assembly 2 includes an end cap 21 covering the opening. The electrode assembly 3 is disposed in the receiving cavity 11 and includes two end faces disposed opposite to each other and a side face connecting the two end faces. The heat-conducting element 4 is disposed in the receiving cavity 11 and is located on at least part of the side face, and is connected to the end cap 21. The heat-conducting element 4 is wrapped around the side face. The heat-conducting element 4 is provided with a connecting portion 40 extending toward the end cap 21. The connecting portion 40 includes an extension section 401 and a bending section 402. The extension section 401 is connected between the bending section 402 and the heat-conducting element 4, and the side of the bending section 402 away from the heat-conducting element 4 is connected to the side of the end cap 21 facing the receiving cavity 11. The end cap assembly 2 also includes an insulating member 22, which is disposed on the side of the end cap 21 facing the electrode assembly 3. The insulating member 22 has a clearance opening 221 for accommodating the bent section 402. The electrode assembly 3 includes two first side surfaces arranged opposite to each other in the first direction X. The heat-conducting member 4 includes two first heat-conducting sheets 41 arranged opposite to each other in the first direction X. Each first heat-conducting sheet 41 is disposed on each of the first side surfaces. At least one first heat-conducting sheet 41 is provided with a connecting portion 40. The electrode assembly 3 also includes two second side surfaces arranged opposite to each other in the second direction Y. The two first side surfaces and the two second side surfaces are alternately connected. The area of ​​the first side surface is larger than the area of ​​the second side surface. The heat-conducting member 4 also includes two second heat-conducting sheets 42. The two first heat-conducting sheets 41 and the two second heat-conducting sheets 42 are alternately connected to surround the electrode assembly 3.

[0221] According to some embodiments of this application, refer to Figures 9 to 16This application provides a battery cell 10, which includes a housing 1, an end cap assembly 2, an electrode assembly 3, and a heat-conducting element 4. The housing 1 forms a receiving cavity 11 with an opening at one end. The end cap assembly 2 includes an end cap 21 covering the opening. The electrode assembly 3 is disposed within the receiving cavity 11 and includes two opposing end faces and a side surface connecting the two end faces. The heat-conducting element 4 is disposed within the receiving cavity 11, located on at least a portion of the side surface, and connected to the end cap 21. The heat-conducting element 4 includes an end face heat-conducting sheet 45 and two first heat-conducting portions 46 disposed opposite each other along a first direction X. The first heat-conducting portions 46 are disposed between the electrode assembly 3 and the housing 1, and the end face heat-conducting sheet 45 is connected between the two first heat-conducting portions 46 and connected to the end cap 21. 1; The number of electrode assemblies 3 is at least two sets, and at least two sets of electrode assemblies 3 are stacked along the first direction X. The heat-conducting component 4 also includes a second heat-conducting part 47, which is disposed between two adjacent sets of electrode assemblies 3. The end face heat-conducting sheet 45 is connected to the second heat-conducting part 47. The battery cell 10 also includes a bracket 5, which is disposed between the end face heat-conducting sheet 45 and the electrode assembly 3. An installation space 50 is formed between the bracket 5 and the end face heat-conducting sheet 45. The end face heat-conducting sheet 45 and the two first heat-conducting parts 46 enclose a covering space 48, and multiple sets of electrode assemblies 3 are located in the covering space 48. The end face heat-conducting sheet 45 is fitted to the end cap 21. The end face heat-conducting sheet 45 has an electrode post hole 451 and / or a pressure relief hole 452.

[0222] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: The shell forms a receiving cavity with an opening at one end; An end cap assembly, including an end cap that covers the opening; An electrode assembly is disposed within the receiving cavity, the electrode assembly including two end faces disposed opposite each other and a side face connecting the two end faces; A heat-conducting element is disposed within the receiving cavity, the heat-conducting element is disposed on at least a portion of the side surface, and the heat-conducting element is connected to the end cap.

2. The battery cell according to claim 1, characterized in that, The heat-conducting element is wound around the side.

3. The battery cell according to claim 1 or 2, characterized in that, The heat-conducting component is provided with a connecting portion extending toward the end cap. The connecting portion includes an extension section and a bending section. The extension section is connected between the bending section and the heat-conducting component. The side of the bending section away from the heat-conducting component is connected to the side of the end cap facing the receiving cavity.

4. The battery cell according to claim 3, characterized in that, The bent section extends from the extended section in a direction away from the sidewall of the housing.

5. The battery cell according to claim 3, characterized in that, The end cap assembly further includes an insulating member disposed on the side of the end cap facing the electrode assembly, the insulating member having a clearance opening for accommodating the bent section.

6. The battery cell according to claim 3, characterized in that, The number of the connecting parts is two, and the two connecting parts are spaced apart and disposed on the same side of the heat-conducting component.

7. The battery cell according to claim 3, characterized in that, The electrode assembly includes two first side surfaces arranged opposite to each other in a first direction, and the heat-conducting element includes two first heat-conducting sheets arranged opposite to each other in the first direction, with each first heat-conducting sheet disposed on each of the first side surfaces. At least one of the first heat-conducting plates is provided with the connecting portion.

8. The battery cell according to claim 7, characterized in that, The electrode assembly also includes two second side surfaces arranged opposite each other in a second direction, with the two first side surfaces and the two second side surfaces being connected alternately in sequence, and the area of ​​the first side surface being larger than the area of ​​the second side surface.

9. The battery cell according to claim 8, characterized in that, The thermal conductive element also includes two second thermal conductive sheets, and the two first thermal conductive sheets and the two second thermal conductive sheets are alternately connected to surround the electrode assembly.

10. The battery cell according to any one of claims 1 to 9, characterized in that, The battery cell includes two or more electrode assemblies and two or more heat-conducting components, with each heat-conducting component corresponding to one of the electrode assemblies.

11. The battery cell according to claim 10, characterized in that, The heat-conducting element is wound around the side surface, and a gap is formed between the two ends of the heat-conducting element wound around the side surface. The gap is located on the side of the electrode assembly corresponding to the heat-conducting element that faces the adjacent electrode assembly.

12. The battery cell according to any one of claims 1 to 9, characterized in that, The end cap is provided with an electrode terminal, and the heat-conducting element has a first opening. The electrode terminal is electrically connected to the tab of the electrode assembly through the first opening.

13. The battery cell according to claim 1, characterized in that, The heat-conducting component includes an end-face heat-conducting sheet and two first heat-conducting portions disposed opposite each other along a first direction. The first heat-conducting portions are disposed between the electrode assembly and the housing. The end-face heat-conducting sheet is connected between the two first heat-conducting portions and connected to the end cap.

14. The battery cell according to claim 13, characterized in that, The number of electrode assemblies is at least two sets, and the at least two sets of electrode assemblies are stacked along the first direction. The heat-conducting component further includes a second heat-conducting part, which is disposed between two adjacent sets of electrode assemblies. The end face heat-conducting sheet is connected to the second heat-conducting part.

15. The battery cell according to claim 14, characterized in that, The second heat-conducting part includes a second main body and two second connecting segments. The second main body is spaced apart from the end face heat-conducting sheet. The second connecting segments are connected between the second main body and the end face heat-conducting sheet. The two second connecting segments are spaced apart along a second direction, and a clearance groove is formed between the two second connecting segments. The second direction and the first direction are perpendicular to each other.

16. The battery cell according to claim 14, characterized in that, The battery cell also includes a bracket, which is disposed between the end face heat-conducting sheet and the electrode assembly, and an installation space is formed between the bracket and the end face heat-conducting sheet.

17. The battery cell according to claim 16, characterized in that, The bracket includes a first support portion and a second support portion, which are respectively disposed on both sides of the second heat-conducting portion along the first direction, and a gap is formed between the first support portion and the second support portion for the second heat-conducting portion to pass through.

18. The battery cell according to claim 16, characterized in that, The bracket includes a support section and two raised sections. The support section is spaced apart from the end face heat-conducting sheet. The raised sections extend from the support section toward the end cap, and the two raised sections are spaced apart along a second direction. The end face heat-conducting sheet, the support section, and the two raised sections enclose at least part of the installation space. The second direction and the first direction are perpendicular to each other.

19. The battery cell according to claim 14, characterized in that, The end face heat-conducting sheet and the two first heat-conducting parts enclose a covering space, and multiple sets of the electrode assemblies are located within the covering space.

20. The battery cell according to any one of claims 13 to 19, characterized in that, The end face heat-conducting sheet is fitted to the end cover; The end face heat-conducting sheet has a pole hole, and / or the end face heat-conducting sheet has a pressure relief hole.

21. The battery cell according to claim 20, characterized in that, The end cap is provided with an electrode terminal, one end of which passes through the electrode post hole and is electrically connected to the tab of the electrode assembly.

22. The battery cell according to any one of claims 1 to 21, characterized in that, The heat-conducting component includes a heat-conducting sheet and an insulating film covering the heat-conducting sheet. The thermal conductivity k of the heat-conducting sheet satisfies k≥500W / (m·K).

23. The battery cell according to claim 22, characterized in that, The heat-conducting sheet is made of graphite, graphene, or carbon nanotubes.

24. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 23.

25. An electrical appliance, characterized in that, The battery cell includes any one of claims 1 to 23, the battery cell being used to provide electrical energy; or the battery device includes the battery device of claim 24, the battery device being used to provide electrical energy.

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