Battery cell, battery device, and electric device

Abstract

The invention provides a battery monomer, a battery device and a power utilization device. Each battery monomer comprises a shell, an electrode terminal and an insulating patch; the housing includes a wall body. The electrode terminal is arranged on the wall body. The insulating patch is arranged on the outer surface of the wall body. The insulating patch comprises an insulating layer and a composite layer which are mutually laminated. The composite layer comprises a first layer body and a second layer body. The heat conductivity coefficient of the first layer body is larger than that of the second layer body. The first layer body is arranged corresponding to the electrode terminal. The battery monomer provided by the invention is beneficial to reducing the possibility of thermal runaway of the battery monomer.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development. Improving battery safety has always been a key research direction in battery technology development. Summary of the Invention

[0003] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device, which helps to reduce the possibility of thermal runaway in the battery cell.

[0004] This application provides a battery cell, which includes a casing, electrode terminals, and insulating pads.

[0005] The outer casing includes a wall. Electrode terminals are disposed on the wall. An insulating patch is disposed on the outer surface of the wall. The insulating patch includes an insulating layer and a composite layer stacked on top of each other. The composite layer includes a first layer and a second layer. The thermal conductivity of the first layer is greater than that of the second layer. The first layer is positioned corresponding to the electrode terminals.

[0006] In the battery cell of this application embodiment, the area on the insulating patch where the first layer is disposed has a relatively high heat dissipation capacity. The arrangement of the area on the insulating patch where the first layer is disposed corresponds to the electrode terminal arrangement, allowing heat at the electrode terminal to be effectively dissipated through this area, thus reducing the possibility of high temperature rise at the electrode terminal and consequently reducing the possibility of high temperature rise in the overall battery cell. Furthermore, the area on the insulating patch where the second layer is disposed has a relatively low thermal conductivity. When the ambient temperature of the battery cell is relatively low, the battery cell can still dissipate heat through the area on the insulating patch where the second layer is disposed. Conversely, when the ambient temperature of the battery cell is relatively high, the area on the insulating patch where the second layer is disposed helps to slow down the transfer of external heat from most areas other than the electrode terminals to the battery cell, thereby reducing the possibility of high temperature rise in the battery cell. The insulating patch improves the heat dissipation effect of the battery cell and effectively slows down the conduction of external heat into the battery cell when the ambient temperature is relatively high. Therefore, the insulating patch achieves a functional balance between heat dissipation and insulation of external heat, thereby reducing the possibility of thermal runaway in the battery cell.

[0007] In some feasible ways, at least part of the composite layer is disposed on the insulating side facing the wall.

[0008] An insulating layer can protect the composite layer from the outside, reducing the possibility of structural damage caused by impacts or scratches.

[0009] In some feasible ways, the first layer and the second layer are connected.

[0010] The insulating patch formed by the insulating layer and the composite layer has better overall structural integrity. The way the first and second layers are connected eliminates the air gap between them. Therefore, after the first layer absorbs heat from the electrode terminal, some of the heat from the first layer can be conducted to the second layer. Thus, the first and second layers can work together to dissipate heat from the electrode terminal, ensuring that the insulating patch has good heat dissipation performance.

[0011] The first and second layers are connected, creating a connecting force between them. This mutual constraint ensures that the first and second layers are not prone to positional displacement.

[0012] In some feasible ways, the thickness of the first layer is greater than the thickness of the second layer.

[0013] The thicker first layer has better heat dissipation performance, which improves its heat dissipation efficiency and further enhances heat dissipation at the electrode terminals, reducing the possibility of temperature rise at the electrode terminals and individual battery cells. The second layer is relatively thin, so it has a relatively small volume while meeting thermal conductivity requirements, which helps to reduce its space occupancy.

[0014] In some feasible implementations, the second layer is a thermal insulation layer, and the material of the second layer is different from that of the insulation layer.

[0015] The second layer has a relatively low thermal conductivity, which helps to further reduce the heat transfer efficiency from the outside environment to the battery cells when the external ambient temperature is relatively high.

[0016] When the external ambient temperature of the battery cell is relatively high, the second layer can effectively isolate external heat, which helps to reduce the possibility of external heat being rapidly transferred to the battery cell and causing the battery cell to heat up rapidly in a short period of time, thereby reducing the possibility of thermal runaway of the battery cell due to rapid heating.

[0017] In some feasible ways, the material of the second layer is the same as that of the insulating layer, and the second layer is integrally formed with the insulating layer.

[0018] In the same processing step, the insulating layer and the second layer can be integrally formed. Then, the first layer is placed in the corresponding area of ​​the insulating layer, and the first and second layers are connected. The method of using the same material for the second layer as the insulating layer allows the insulating patch to meet insulation and thermal conductivity requirements while reducing production costs. The integral forming of the second layer and the insulating layer ensures that their relative positions remain unchanged and that no air gaps occur, affecting thermal conductivity. Furthermore, it reduces the number of processing steps required for the insulating patch.

[0019] In some feasible implementations, the second layer comprises a first sublayer and a second sublayer connected to the first layer, and the thermal conductivity of the second sublayer is greater than that of the first sublayer.

[0020] After the first layer absorbs the heat from the electrode terminal, some of the heat from the first layer can be conducted to the second sub-layer. Thus, the first and second sub-layers can work together to dissipate heat from the electrode terminal, ensuring that the insulating patch has a good heat dissipation effect.

[0021] The thermal conductivity of different regions on the insulating patch, corresponding to the first layer, the first sublayer, and the second sublayer, varies. The insulating patch can be flexibly designed with a composite layer structure to meet the thermal conductivity requirements of different regions on the battery cell. This ensures that the composite layer's structural design accurately meets the thermal conductivity requirements, allowing the insulating patch to simultaneously perform insulation and thermal conductivity functions, thus improving its adaptability.

[0022] In some feasible implementations, the first sublayer is an insulating material layer, and the materials of any two of the first layer, the first sublayer, and the second sublayer are different.

[0023] The materials for the first layer, the first sublayer, and the second sublayer can be flexibly selected according to the thermal conductivity requirements, so that the first layer, the first sublayer, and the second sublayer can each take into account both insulation and thermal conductivity functions, thereby improving the adaptability of the insulating patch.

[0024] In some feasible ways, the material of the second sublayer is the same as that of the insulating layer, and the second sublayer and the insulating layer are integrally formed.

[0025] The use of the same material for the second sublayer as the insulating layer allows the insulating patch to meet insulation and thermal conductivity requirements while reducing production costs. The integral molding of the second sublayer and the insulating layer ensures that their relative positions remain unchanged and that they do not separate, preventing air gaps that could affect thermal conductivity. Furthermore, it reduces the number of processing steps required for the insulating patch.

[0026] In some feasible embodiments, the insulating layer includes a first insulating segment and a second insulating segment, a first layer body is disposed on the first insulating segment to form a first sub-pattern, a second layer body is disposed on the second insulating segment to form a second sub-pattern, and the first sub-pattern and the second sub-pattern are spliced ​​together to form an insulating patch.

[0027] The insulating patch includes a first sub-patch and a second sub-patch. The appropriate first and second sub-patches can be selected and spliced ​​together to form the insulating patch according to the size changes of the wall and the heat conduction requirements. This helps to improve the overall molding freedom of the insulating patch and enhance its adaptability.

[0028] In some feasible ways, the thermal conductivity of the first layer is greater than or equal to 5 W / m·°C, and the thermal conductivity of the second layer is less than or equal to 1 W / m·°C.

[0029] If the thermal conductivity of the first layer is less than 5 W / m·°C, its heat dissipation capacity is relatively poor, making it difficult to meet the heat dissipation requirements of the electrode terminals. This could lead to low heat dissipation efficiency at the electrode terminals, resulting in a rapid temperature rise. If the thermal conductivity of the second layer is greater than 1 W / m·°C, its heat insulation capacity is relatively poor, making it difficult to meet the heat insulation requirements of the external environment when the external temperature is relatively higher. This could lead to a relatively fast heat transfer rate from the external environment to the battery cells, resulting in a rapid temperature rise in the battery cells.

[0030] In some feasible implementations, the insulating patch has clearance holes in the area corresponding to the first layer, through which the electrode terminals pass.

[0031] The electrode terminals pass through the clearance holes in the insulating patch. The first layer surrounds the electrode terminals, allowing the first layer to dissipate heat from various locations around the electrode terminals, thus improving the heat dissipation effect of the insulating patch.

[0032] In some feasible embodiments, the battery cell also includes a pressure relief device disposed on the wall, and a second layer disposed corresponding to the pressure relief device, the second layer shielding at least part of the pressure relief device.

[0033] The second layer protects the pressure relief component. When the ambient temperature of the battery cell is relatively high, the second layer effectively isolates external heat from being conducted to the pressure relief component. This reduces the likelihood of external heat being rapidly transferred to the pressure relief component and causing it to heat up quickly in a short time. Consequently, it reduces the possibility of the pressure relief component melting quickly due to a rapid temperature rise, or of heat being rapidly conducted into the battery cell through the pressure relief component. This further reduces the possibility of thermal runaway in the battery cell due to melting of the pressure relief component or rapid heating of the battery cell.

[0034] In some feasible methods, the area on the insulating patch corresponding to the second layer is provided with annular grooves.

[0035] When the pressure relief device opens to release the internal pressure of the battery cell, the insulating patch is subjected to impact force, and the insulating patch is prone to breakage at the annular notch. This ensures that the insulating patch does not affect the normal pressure relief of the pressure relief device, reducing the possibility of battery cell explosion due to poor pressure relief of the pressure relief device.

[0036] In some feasible methods, the area on the insulating patch corresponding to the second layer is provided with multiple serration lines, which are arranged in a ring at intervals.

[0037] When the pressure relief device opens to release the internal pressure of the battery cell, the insulating patch is subjected to impact force, and the insulating patch is prone to breakage at the etched line. This ensures that the insulating patch does not affect the normal pressure relief of the pressure relief device, reducing the possibility of battery cell explosion due to poor pressure relief of the pressure relief device.

[0038] In some feasible methods, the insulating patch has multiple through holes in the area corresponding to the second layer, and the multiple through holes are arranged in a ring-shaped interval.

[0039] When the pressure relief device opens to release the internal pressure of the battery cell, the insulating patch is subjected to impact force, and the insulating patch is prone to breakage in the area where the through hole is set. This ensures that the insulating patch does not affect the normal pressure relief of the pressure relief device, reducing the possibility of battery cell explosion due to poor pressure relief of the pressure relief device.

[0040] In some feasible embodiments, two electrode terminals are provided on the wall, a pressure relief element is located between the two electrode terminals, and the composite layer includes two first layers with a second layer disposed between the two first layers.

[0041] The two first layers dissipate heat from the two electrode terminals respectively. The area on the wall between the two electrode terminals is relatively large. The second layer can shield the area on the wall between the two electrode terminals, thereby slowing down the conduction of external heat to the battery cells through the area between the two electrode terminals when the external ambient temperature is relatively high.

[0042] In some feasible embodiments, the insulating patch also includes an adhesive layer, with the insulating layer, composite layer and adhesive layer stacked together, the adhesive layer disposed on the side of the composite layer opposite to the insulating layer, and the adhesive layer bonded to the wall.

[0043] When connecting the insulating patch to the wall, the insulating patch can be adhered to the outer surface of the wall using an adhesive layer to fix its position. This connection method is simple and easy to operate, reducing the difficulty of connecting the insulating patch to the wall. The adhesive layer can be a thermally conductive material, without affecting the heat conduction between the insulating patch and the wall.

[0044] The adhesive layer can effectively fill the gap between the composite layer and the wall. On the one hand, it reduces the possibility that air gaps between the composite layer and the wall may affect the thermal conductivity between them. On the other hand, it ensures a large connection area between the insulating patch and the wall, reducing the possibility that the connection force between the insulating patch and the wall may decrease due to gaps between them.

[0045] In some feasible implementations, the housing includes a shell and end caps, with the end caps connected to the shell and serving as walls.

[0046] This application provides a battery device that includes the aforementioned battery cell.

[0047] This application provides an electrical device including the battery device described above. The battery device is used to provide electrical energy. Attached Figure Description

[0048] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0049] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0050] Figure 2 This is a schematic diagram of the structure of a battery device provided in an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of the application;

[0052] Figure 4 This is a partial structural schematic diagram of a battery cell provided in an embodiment of this application;

[0053] Figure 5 This is a partially exploded structural diagram of a battery cell provided in an embodiment of this application;

[0054] Figure 6 This is a partial structural schematic diagram of an insulating patch provided in an embodiment of this application;

[0055] Figure 7 This is a partially exploded structural diagram of an insulating patch provided in an embodiment of this application;

[0056] Figure 8 This is a partial structural schematic diagram of an insulating patch provided in an embodiment of this application;

[0057] Figure 9 This is a partial structural schematic diagram of an insulating patch provided in an embodiment of this application;

[0058] Figure 10 This is a partially exploded structural diagram of an insulating patch provided in an embodiment of this application;

[0059] Figure 11 This is a partial structural schematic diagram of an insulating patch provided in an embodiment of this application;

[0060] Figure 12 This is a partial structural schematic diagram of an insulating patch provided in an embodiment of this application;

[0061] Figure 13 This is a partially exploded structural diagram of an insulating patch provided in one embodiment of this application;

[0062] Figure 14 A partial structural schematic diagram of an insulating patch provided in one embodiment of this application;

[0063] Figure 15 This is a partially exploded structural diagram of an insulating patch provided in one embodiment of this application;

[0064] Figure 16 This is a partially exploded structural diagram of a battery cell provided in one embodiment of this application;

[0065] Figure 17 A partial structural schematic diagram of an insulating patch provided in one embodiment of this application;

[0066] Figure 18 A partial structural schematic diagram of an insulating patch provided in one embodiment of this application;

[0067] Figure 19 This is a partial structural diagram of an insulating patch provided in one embodiment of this application.

[0068] Explanation of reference numerals in the attached figures:

[0069] 1. Vehicles;

[0070] 10. Battery assembly; 10a. Housing; 10b. First housing section; 10c. Second housing section; 11. Controller; 12. Motor;

[0071] 20. Battery module;

[0072] 30. Battery cell; 301. Casing;

[0073] 40. End cap; 40a. Outer surface; 41. Electrode terminal;

[0074] 50. Shell;

[0075] 60. Electrode assembly;

[0076] 70. Pressure relief components;

[0077] 80. Insulating patch; 801. Clearance hole; 802. Circular notch; 803. Notch line; 804. Through hole; 805. First window; 806. Second window; 81. First sub-pattern; 82. Second sub-pattern;

[0078] 90. Insulating layer; 91. First insulating section; 92. Second insulating section;

[0079] 100. Composite layer; 101. First layer; 102. Second layer; 1021. First sublayer; 1022. Second sublayer;

[0080] 200. Adhesive layer;

[0081] Z, thickness direction. Detailed Implementation

[0082] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0083] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0084] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0085] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0086] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0087] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0088] 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.

[0089] In this application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto. The battery cell may be flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0090] 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. The battery device mentioned in this application can be a battery pack. For example, the battery device mentioned in this application can include battery modules, etc. A battery device 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.

[0091] A single battery cell consists of electrode components and an electrolyte. The electrode components include a positive electrode, a negative electrode, and a separator. A single battery cell primarily functions by the movement of metal ions between the positive and negative electrode plates.

[0092] The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector includes a positive current collection section and a positive electrode tab connected to the current collection section. The positive current collection section is coated with the positive active material layer. The positive electrode tab is not coated with the positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum. The positive active material layer includes the positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.

[0093] The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector includes a negative electrode current collection section and a negative electrode tab connected to the negative electrode current collection section. The negative electrode current collection section is coated with the negative electrode active material layer. The negative electrode tab is not coated with the negative electrode active material layer. The material of the negative electrode current collector can be copper. The negative electrode active material layer includes the negative electrode active material. The negative electrode active material can be carbon or silicon, etc.

[0094] The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0095] The inventors have observed that heat is generated at the electrode terminals of a battery cell during charging. This heat is conducted into the battery cell. If the separator absorbs excessive heat, causing its own temperature to become too high, the separator may shrink or break, potentially leading to a short circuit between the positive and negative electrodes, and consequently, thermal runaway of the battery cell. In related technologies, heat dissipation patches are placed on the end caps of the battery cells. The thermally conductive layer in the heat dissipation patch is a single, integral structure. The heat dissipation patch can improve the heat dissipation capacity of the end cap and electrode terminals, thus reducing the temperature of the battery cell. However, because the thermally conductive layer in the heat dissipation patch is a single, integral structure, when the ambient temperature of the battery cell is relatively high, external heat can be rapidly transferred to the battery cell through the thermally conductive layer, resulting in a faster temperature rise and a greater likelihood of thermal runaway.

[0096] To mitigate the problem of thermal runaway in individual battery cells, the applicant discovered that different areas of the insulating patch can be configured with varying thermal conductivity. Areas with relatively high thermal conductivity correspond to the electrode terminals, while areas with relatively low thermal conductivity correspond to other areas outside the electrode terminals.

[0097] Based on the above considerations, the inventors, through in-depth research, designed a battery cell. In this battery cell, the areas of the insulating patch with relatively high thermal conductivity can dissipate heat from the electrode terminals, achieving good heat dissipation at the electrode terminals and reducing the possibility of high temperature rise at the electrode terminals, thereby reducing the possibility of high temperature rise in the battery cell. When the external ambient temperature of the battery cell is relatively high, the areas of the insulating patch with relatively low thermal conductivity can help slow down the transfer of external heat from other areas besides the electrode terminals to the battery cell, thus helping to reduce the possibility of high temperature rise in the battery cell. The insulating patch can effectively improve the heat dissipation efficiency at the electrode terminals while effectively reducing the conduction efficiency of external heat into the battery cell. Therefore, the insulating patch can help achieve a balance between heat dissipation and heat isolation, thereby helping to reduce the possibility of thermal runaway in the battery cell.

[0098] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0099] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. 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. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. 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. This application does not impose any special limitations on the above-mentioned electrical devices.

[0100] 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.

[0101] Figure 1 The structure of vehicle 1 is shown schematically. See also Figure 1 As shown, vehicle 1 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 10 is installed inside vehicle 1. The battery device 10 can be located at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1. For example, the battery device 10 can serve as the operating power source for vehicle 1. Vehicle 1 may also include a controller 11 and a motor 12. The controller 11 is used to control the battery device 10 to supply power to the motor 12. For example, this is for the power needs of vehicle 1 during starting, navigation, and driving.

[0102] In some embodiments of this application, the battery device 10 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1.

[0103] To meet different power demands, the battery device 10 may include multiple battery cells. A battery cell is the smallest unit that makes up a battery module or battery pack. Multiple battery cells can be connected in series and / or in parallel via electrode terminals for various applications. The battery mentioned in this application includes battery modules or battery packs. Multiple battery cells can be connected in series, parallel, or a combination thereof. A combination thereof refers to a mix of series and parallel connections. In the embodiments of this application, multiple battery cells can be directly assembled into a battery pack, or they can first be assembled into a battery module 20, and then the battery module 20 can be assembled into a battery pack.

[0104] Figure 2 The structure of the battery device 10 is shown schematically. See also Figure 2 As shown, the battery includes a housing 10a and individual battery cells (not shown). The individual battery cells are housed within the housing 10a.

[0105] The housing 10a can be a simple three-dimensional structure such as a single cuboid, cylinder, or sphere, or it can be a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders, or spheres. This application embodiment does not limit this. The material of the housing 10a can be an alloy material such as aluminum alloy or iron alloy, or a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin. This application embodiment also does not limit this.

[0106] The housing 10a is used to accommodate individual battery cells, and the housing 10a can have various structures. In some embodiments, the housing 10a may include a first housing portion 10b and a second housing portion 10c. The first housing portion 10b and the second housing portion 10c overlap each other. The first housing portion 10b and the second housing portion 10c together define a receiving space for accommodating the individual battery cells. The second housing portion 10c may be a hollow structure with one open end. In some embodiments, the first housing portion 10b is a plate-like structure. The first housing portion 10b overlaps the open side of the second housing portion 10c to form a housing 10a with a receiving space. In some embodiments, both the first housing portion 10b and the second housing portion 10c may also be hollow structures with one open side. The open side of the first housing portion 10b overlaps the open side of the second housing portion 10c to form a housing 10a with a receiving space. Of course, the first housing portion 10b and the second housing portion 10c can have various shapes, such as cylinders, cuboids, etc.

[0107] To improve the sealing performance after the first housing part 10b and the second housing part 10c are connected, a sealing element, such as sealant or sealing ring, can also be provided between the first housing part 10b and the second housing part 10c.

[0108] In some embodiments, the first housing portion 10b covers the top of the second housing portion 10c. The first housing portion 10b may also be referred to as the upper housing cover, and the second housing portion 10c may also be referred to as the lower housing.

[0109] In a battery, there can be one or more individual cells. When there are multiple individual cells, they can be connected in series, parallel, or a combination thereof. A combination thereof means that multiple individual cells are connected in both series and parallel configurations. Multiple individual cells can be directly connected in series, parallel, or a combination thereof, and then the entire assembly of the individual cells is housed within the housing 10a. Alternatively, multiple individual cells can first be connected in series, parallel, or a combination thereof to form a battery module. Multiple battery modules can then be connected in series, parallel, or a combination thereof to form a whole, which is then housed within the housing 10a.

[0110] In some embodiments, Figure 3 The structure of battery module 20 is shown schematically. See also Figure 3 As shown, there can be multiple battery cells 30. Multiple battery cells 30 are first connected in series, parallel, or in a mixed connection to form a battery module 20. Multiple battery modules 20 are then connected in series, parallel, or in a mixed connection to form a whole, which is housed in the casing 10a.

[0111] Multiple battery cells 30 in the battery module 20 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 30 in the battery module 20.

[0112] In this embodiment, the battery cell 30 may include a lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and this embodiment is not limited thereto. The battery cell 30 may be flat, cuboid, or other shapes, and this embodiment is not limited thereto either. However, for the sake of brevity, the following embodiment uses a cuboid battery cell 30 as an example for illustration.

[0113] Figure 4 A partial structure of the battery cell 30 is shown schematically. Figure 5 The diagram schematically shows a partially disassembled structure of the battery cell 30. The battery cell 30 refers to the smallest unit comprising the battery assembly 10. See also... Figure 4 and Figure 5 As shown, the battery cell 30 includes an end cap 40, a housing 50, and an electrode assembly 60.

[0114] End cap 40 refers to a component that covers the opening of housing 50 to isolate the internal environment of battery cell 30 from the external environment. Exemplarily, the shape of end cap 40 can be adapted to the shape of housing 50 to fit it. Exemplarily, end cap 40 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 40 is not easily deformed under pressure or impact, enabling battery cell 30 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 41 can be provided on end cap 40. Electrode terminals 41 can be electrically connected to electrode assembly 60 via metal connectors for outputting or inputting electrical energy into battery cell 30. When electrode assembly 60 generates heat, some of the heat can be conducted to electrode terminals 41 via metal connectors and can be dissipated from electrode terminals 41.

[0115] In some embodiments, the end cap 40 may also be provided with a pressure relief component 70 for releasing internal pressure when the internal pressure or temperature of the battery cell 30 reaches a threshold. For example, the pressure relief component 70 may be a pressure relief valve. The end cap 40 may also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating component may also be provided on the inner side of the end cap 40. The insulating component may be used to isolate the electrical connection components within the housing 50 from the end cap 40 to reduce the risk of short circuit. Exemplarily, the insulating component may be plastic, rubber, etc.

[0116] The housing 50 is a component used to cooperate with the end cap 40 to form the internal environment of the battery cell 30. The formed internal environment can accommodate the electrode assembly 60, electrolyte (not shown in the figure), and other components. The housing 50 and the end cap 40 can be independent components. An opening can be provided on the housing 50, and the end cap 40 closes the opening to form the internal environment of the battery cell 30. Alternatively, the end cap 40 and the housing 50 can be integrated. Specifically, the end cap 40 and the housing 50 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 50, the end cap 40 closes the housing 50. The housing 50 can be of various shapes and sizes, such as cuboid, hexagonal prism, etc. Specifically, the shape of the housing 50 can be determined according to the specific shape and size of the electrode assembly 60. The material of the housing 50 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment does not impose any special limitations on this.

[0117] Electrode assembly 60 is the component in the battery cell 30 where electrochemical reactions occur. The housing 50 may contain one or more electrode assemblies 60. Electrode assembly 60 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly. The portions of the positive and negative electrode sheets without active material each constitute a tab (not shown in the figure). The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0118] Figure 6 A partial structure of the insulating patch 80 is shown schematically. Figure 7 A partial exploded view of the insulating patch 80 is schematically shown. See also Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, this application embodiment provides a battery cell 30. The battery cell 30 includes a housing 301, electrode terminals 41, and an insulating patch 80. The housing 301 includes a wall. The electrode terminals 41 are disposed on the wall. The insulating patch 80 is disposed on the outer surface 40a of the wall. The insulating patch 80 includes an insulating layer 90 and a composite layer 100 stacked on top of each other. The composite layer 100 includes a first layer 101 and a second layer 102. The thermal conductivity of the first layer 101 is greater than that of the second layer 102. The first layer 101 is disposed corresponding to the electrode terminals 41.

[0119] The housing 301 is a structural component used to isolate the internal environment of the battery cell 30 from the external environment. The housing 301 houses the electrode assembly 60, electrolyte, and other components. The housing 301 may include a shell 50 and an end cap 40. The end cap 40 is connected to the shell 50. For ease of description, the following embodiments use the end cap 40 as an example wall. The electrode terminal 41 is connected to the wall of the housing 301 to fix its position. A seal is formed between the electrode terminal 41 and the wall of the housing 301, reducing the possibility of electrolyte leakage between the electrode terminal 41 and the wall of the housing 301. In some examples, a portion of the electrode terminal 41 protrudes from the outer surface 40a of the wall. An insulating patch 80 can be bonded to the outer surface 40a of the wall. The insulating patch 80 can provide insulation protection. Along the thickness direction Z of the insulating patch 80, the insulating layer 90 and the composite layer 100 can be stacked on top of each other. The insulating layer 90 and the composite layer 100 can be bonded to each other. The first layer 101 and the second layer 102 of the composite layer 100 each have different thermal conductivity, resulting in different thermal conductivity in different areas of the insulating patch 80 as a whole. The first layer 101 is positioned relatively close to the electrode terminal 41 to effectively dissipate heat from the electrode terminal 41. The first layer 101 can separate the electrode terminal 41 and the second layer 102. The second layer 102 is positioned relatively far from the electrode terminal 41. The second layer 102 can be positioned corresponding to other areas on the wall.

[0120] In the battery cell 30 of this embodiment, the area on the insulating patch 80 where the first layer 101 is disposed has a relatively high heat dissipation capacity. The arrangement of the area on the insulating patch 80 where the first layer 101 is disposed corresponds to the electrode terminal 41, allowing heat at the electrode terminal 41 to be effectively dissipated through this area. This helps reduce the likelihood of a high temperature rise at the electrode terminal 41, thereby reducing the overall likelihood of a high temperature rise in the battery cell 30. Furthermore, the area on the insulating patch 80 where the second layer 102 is disposed has a relatively low thermal conductivity. When the ambient temperature of the battery cell 30 is relatively low, the battery cell 30 can still dissipate heat through the area on the insulating patch 80 where the second layer 102 is disposed. Conversely, when the ambient temperature of the battery cell 30 is relatively high, the area on the insulating patch 80 where the second layer 102 is disposed helps to slow down the transfer of external heat from most areas other than the electrode terminal 41 to the battery cell 30, thereby reducing the likelihood of a high temperature rise in the battery cell 30. The insulating patch 80 can improve the heat dissipation of the battery cell 30. At the same time, it can effectively slow down the conduction of external heat into the battery cell 30 when the external ambient temperature is relatively high. Thus, the insulating patch 80 can achieve a functional balance between heat dissipation and isolation of external heat, which helps to reduce the possibility of thermal runaway of the battery cell 30.

[0121] In some feasible implementations, the first layer 101 and the second layer 102 of the composite layer 100 are disposed in the same layer. Along the thickness direction Z of the insulating patch 80, the first layer 101 and the second layer 102 are located on the same side of the insulating layer 90. In some examples, the first layer 101, the second layer 102, and the insulating layer 90 are each manufactured independently. The composite layer 100 can be bonded to the insulating layer 90 to form the insulating patch 80. In some examples, the composite layer 100 can be formed by spraying thermally conductive materials with different thermal conductivity coefficients onto different areas of the insulating layer 90 using a spraying process.

[0122] In some feasible embodiments, at least a portion of the composite layer 100 is disposed on the side of the insulating layer 90 facing the wall of the housing 301. The spacing between the composite layer 100 and the wall of the housing 301 is relatively small. The insulating layer 90 can provide protection for the composite layer 100 from the outside, reducing the possibility of structural damage to the composite layer 100 due to impact or scratches.

[0123] In some examples, the composite layer 100 is integrally disposed on the side of the insulating layer 90 facing the wall of the housing 301.

[0124] In some implementations, the first layer 101 and the second layer 102 are connected. There is no gap between the first layer 101 and the second layer 102 in the connection area. Therefore, the structural integrity of the insulating patch 80 formed by the insulating layer 90 and the composite layer 100 is better. In some examples, the first layer 101 and the second layer 102 can be in contact with each other. In some examples, the first layer 101 has a side facing away from the electrode terminal 41. The second layer 102 has a side facing the electrode terminal 41. The side of the first layer 101 facing away from the electrode terminal 41 is connected to the side of the second layer 102 facing the electrode terminal 41. In some examples, the first layer 101 and the second layer 102 are bonded together.

[0125] The way the first layer 101 and the second layer 102 are connected allows for the elimination of air gaps between them. Therefore, after the first layer 101 absorbs heat from the electrode terminal 41, some of the heat from the first layer 101 can be conducted to the second layer 102. Thus, the first layer 101 and the second layer 102 can work together to dissipate heat from the electrode terminal 41, ensuring that the insulating patch 80 has good heat dissipation performance.

[0126] The first layer 101 and the second layer 102 are connected, so that there is a connecting force between the first layer 101 and the second layer 102, thereby limiting and constraining the first layer 101 and the second layer 102 to ensure that the first layer 101 and the second layer 102 are not prone to positional displacement.

[0127] In some feasible ways, Figure 8 A partial structure of the insulating patch 80 is schematically shown. See also Figure 8 As shown, the thickness of the first layer 101 is greater than the thickness of the second layer 102. The thicker first layer 101 has better heat dissipation performance, which improves its heat dissipation efficiency and further enhances heat dissipation at the electrode terminal 41, reducing the possibility of temperature rise at the electrode terminal 41 and the battery cell 30. The second layer 102 has a relatively smaller thickness, resulting in a smaller volume while meeting thermal conductivity requirements, thus reducing its space occupancy. Consequently, the total thickness of the area on the insulating patch 80 corresponding to the second layer 102 is relatively small. When multiple battery cells 30 are grouped together to form a battery module, the area on the insulating patch 80 corresponding to the second layer 102 can have a smaller space occupancy, saving more space for arranging other structural components.

[0128] In some examples, a portion of the electrode terminal 41 protrudes from the outer surface 40a of the wall of the housing 301. A gap exists between the top surface of the electrode terminal 41 and the outer surface 40a of the wall along the thickness direction Z of the insulating patch 80. The total thickness of the region on the insulating patch 80 corresponding to the first layer 101 is less than the gap between the top surface of the electrode terminal 41 and the outer surface 40a of the wall, thus causing a portion of the electrode terminal 41 to protrude from the surface of the insulating patch 80 facing away from the wall.

[0129] In some feasible implementations, the second layer 102 is a thermal insulation material layer. The second layer 102 has good external heat insulation performance. The material of the second layer 102 is different from that of the insulating layer 90. The thermal conductivity of the second layer 102 is relatively low, which can help to further reduce the conduction efficiency of external heat to the battery cell 30 when the external ambient temperature is relatively high.

[0130] When the external ambient temperature of the battery cell 30 is relatively high, the second layer 102 can effectively isolate external heat, which helps to reduce the possibility of external heat being rapidly transferred to the battery cell 30 and causing the battery cell 30 to heat up rapidly in a short time, thereby reducing the possibility of thermal runaway of the battery cell 30 due to rapid heating.

[0131] For example, in a battery module comprising multiple battery cells 30, when one battery cell 30 experiences thermal runaway, the high-temperature material ejected from that cell is more likely to affect other normal battery cells 30 in the vicinity. Since adjacent battery cells 30 include insulating patches 80, these patches can effectively isolate the heat generated by the high-temperature material, thereby reducing the likelihood of normal battery cells 30 also experiencing thermal runaway and effectively improving the safety of the battery module.

[0132] In some examples, the material of the second layer 102 is an insulating material with a high melting point and low thermal conductivity. Exemplarily, the melting point of the second layer 102 can be greater than 200 degrees Celsius (°C). Exemplarily, the material of the second layer 102 can include, but is not limited to, soluble polytetrafluoroethylene (PFA), aerogel, silica, mica, glass fiber, ceramics, and ceramic rubber. The material of the insulating layer 90 can include, but is not limited to, polycarbonate (PC), polyethylene terephthalate (PET), or polypropylene (PP).

[0133] In some feasible ways, the thermal conductivity of the first layer 101 can be greater than or equal to 5 W / m·K. The thermal conductivity of the second layer 102 can be less than or equal to 1 W / m·K.

[0134] If the thermal conductivity of the first layer 101 is less than 5 W / m·°C, its heat dissipation capacity is relatively poor, making it difficult to meet the heat dissipation requirements of the electrode terminal 41. This could lead to a low heat dissipation efficiency of the electrode terminal 41, resulting in a rapid temperature rise. If the thermal conductivity of the second layer 102 is greater than 1 W / m·°C, its heat insulation capacity is relatively poor, making it difficult to meet the heat insulation requirements of the external environment when the external temperature is relatively higher. This could lead to a relatively fast heat transfer rate from the external environment to the battery cell 30, resulting in a rapid temperature rise.

[0135] In some examples, the material of the first layer 101 is different from the material of the second layer 102. The material of the first layer 101 is an insulating material with a high melting point and high thermal conductivity. For example, the melting point of the first layer 101 can be greater than 200 degrees Celsius (°C). For example, the material of the first layer 101 can include, but is not limited to, boron nitride, gallium nitride, epoxy resin-based materials, aluminum nitride, silicon carbide, and beryllium oxide.

[0136] In some feasible implementations, the material of the second layer 102 is the same as that of the insulating layer 90. In some examples, the first layer 101, the second layer 102, and the insulating layer 90 are each manufactured independently. The composite layer 100 can be bonded to the insulating layer 90 to form an insulating patch 80.

[0137] The fact that the material of the second layer 102 is the same as that of the insulating layer 90 allows the second layer 102 to meet the requirements of insulation and external heat insulation performance while reducing the production cost of the second layer 102. The second layer 102 and the insulating layer 90 can be manufactured using the same processing technology, which helps to reduce the processing difficulty of the second layer 102 and reduce the processing steps of the insulating patch 80.

[0138] In some feasible ways, Figure 9 A partial structure of the insulating patch 80 is schematically shown. See also Figure 9As shown, the material of the second layer 102 is the same as that of the insulating layer 90. The second layer 102 and the insulating layer 90 are integrally formed. The insulating layer 90 and the second layer 102 can be integrally formed in the same processing step, and then the first layer 101 is provided in the corresponding area of ​​the insulating layer 90, with the first layer 101 and the second layer 102 connected. The fact that the material of the second layer 102 is the same as that of the insulating layer 90 allows the insulating patch 80 to meet insulation and thermal conductivity requirements while reducing production costs. The integral forming of the second layer 102 and the insulating layer 90 ensures that the relative positions of the second layer 102 and the insulating layer 90 do not change, and that the second layer 102 and the insulating layer 90 do not separate, creating air gaps that would affect thermal conductivity. Furthermore, it reduces the number of processing steps required for the insulating patch 80.

[0139] In some feasible ways, Figure 10 A partial exploded view of the insulating patch 80 is schematically shown. See also Figure 10 As shown, the second layer 102 includes a first sublayer 1021 and a second sublayer 1022. The second sublayer 1022 is connected to the first layer 101. The second sublayer 1022 can isolate the first layer 101 and the first sublayer 1021. The first layer 101 and the first sublayer 1021 are not connected. The thermal conductivity of the second sublayer 1022 is greater than that of the first sublayer 1021, thus the first sublayer 1021 has a better performance in isolating external heat than the second sublayer 1022.

[0140] After the first layer 101 absorbs the heat from the electrode terminal 41, a portion of the heat on the first layer 101 can be conducted to the second sub-layer 1022. Thus, the first layer 101 and the second sub-layer 1022 can work together to dissipate heat from the electrode terminal 41, ensuring that the insulating patch 80 has a good heat dissipation effect.

[0141] The thermal conductivity of different regions on the insulating patch 80 corresponding to the first layer 101, the first sub-layer 1021, and the second sub-layer 1022 varies. The insulating patch 80 can be flexibly designed with the structure of the composite layer 100 according to the thermal conductivity requirements of different regions on the battery cell 30. This ensures that the structural design of the composite layer 100 accurately meets the thermal conductivity requirements, allowing the insulating patch 80 to effectively balance insulation and thermal conductivity, thus improving its adaptability.

[0142] In some examples, the first sublayer 1021 is a thermal insulation material layer. The first sublayer 1021 has good external heat insulation performance. The materials of any two of the first layer 101, the first sublayer 1021, and the second sublayer 1022 are different. The first layer 101, the first sublayer 1021, the second sublayer 1022, and the insulating layer 90 are each manufactured independently. The first layer 101, the first sublayer 1021, and the second sublayer 1022 are joined to form a composite layer 100. The composite layer 100 can be bonded to the insulating layer 90 to form an insulating patch 80.

[0143] The materials of the first layer 101, the first sub-layer 1021, and the second sub-layer 1022 can be flexibly selected according to the thermal conductivity requirements, so that the first layer 101, the first sub-layer 1021, and the second sub-layer 1022 can each take into account both insulation and thermal conductivity functions, thereby improving the adaptability of the insulating patch 80.

[0144] For example, the material of the first layer 101 may include, but is not limited to, boron nitride, gallium nitride, epoxy resin-based materials, aluminum nitride, silicon carbide, and beryllium oxide. The material of the first sublayer 1021 may include, but is not limited to, soluble polytetrafluoroethylene (PFA), aerogel, silica, mica, glass fiber, ceramics, and ceramic rubber. The material of the second sublayer 1022 may include, but is not limited to, polycarbonate (PC), polyethylene terephthalate (PET), or polypropylene (PP).

[0145] For example, the material of the second sublayer 1022 can be the same as the material of the insulating layer 90. This arrangement, where the material of the second sublayer 1022 is the same as that of the insulating layer 90, allows the second sublayer 1022 to meet insulation and external heat insulation performance requirements while reducing production costs. Furthermore, the second sublayer 1022 and the insulating layer 90 can be manufactured using the same processing technology, which helps reduce the processing difficulty of the second sublayer 1022 and decreases the processing steps of the insulating patch 80.

[0146] For example, Figure 11 A partial structure of the insulating patch 80 is schematically shown. See also Figure 11 As shown, the material of the second sub-layer 1022 is the same as that of the insulating layer 90, and the second sub-layer 1022 is integrally formed with the insulating layer 90. The insulating layer 90 and the second sub-layer 1022 can be integrally formed in the same processing step, and then the first layer 101 and the first sub-layer 1021 are disposed in corresponding areas of the insulating layer 90. The first layer 101 and the first sub-layer 1021 are respectively connected to the second sub-layer 1022.

[0147] The fact that the material of the second sub-layer 1022 is the same as that of the insulating layer 90 allows the insulating patch 80 to meet the requirements for insulation and thermal conductivity while reducing the production cost of the insulating patch 80. The integral molding of the second sub-layer 1022 and the insulating layer 90 ensures that their relative positions remain unchanged and that they do not separate, preventing air gaps that could affect thermal conductivity. Furthermore, it reduces the number of processing steps required for the insulating patch 80.

[0148] In some feasible ways, Figure 12 A partial structure of the insulating patch 80 is shown schematically. Figure 13 A partial exploded view of the insulating patch 80 is schematically shown. See also Figure 12 and Figure 13 As shown, the insulating layer 90 includes a first insulating section 91 and a second insulating section 92. A first layer body 101 is correspondingly disposed on the first insulating section 91 to form a first sub-pattern 81. A second layer body 102 is correspondingly disposed on the second insulating section 92 to form a second sub-pattern 82. The first sub-pattern 81 and the second sub-pattern 82 are spliced ​​together to form an insulating patch 80.

[0149] The first sub-pattern 81 and the second sub-pattern 82 are each independent structural components. When it is necessary to install the insulating patch 80 on the wall of the housing 301, the first sub-pattern 81 and the second sub-pattern 82 of appropriate size can be selected and installed on the wall of the housing 301. The first sub-pattern 81 and the second sub-pattern 82 installed on the wall are spliced ​​together to form a complete insulating patch 80.

[0150] The material of the second layer 102 can be a heat-insulating material or the same material as the insulating layer 90. Therefore, the material of the second layer 102 in different second sub-patches 82 can be different. When it is necessary to install an insulating patch 80 on the wall of the outer casing 301, different second sub-patches 82 can be selected according to the thermal conductivity requirements and spliced ​​with the first sub-patches 81 to form a complete insulating patch 80.

[0151] The insulating patch 80 includes a first sub-pattern 81 and a second sub-pattern 82. The appropriate first sub-pattern 81 and second sub-pattern 82 can be selected and spliced ​​together to form the insulating patch 80 according to the size changes of the wall and the heat conduction requirements. This helps to improve the overall molding freedom of the insulating patch 80 and improve the adaptability of the insulating patch 80.

[0152] In some feasible embodiments, the insulating patch 80 is bonded to the wall of the housing 301. An adhesive structure is provided on at least one of the insulating patch 80 and the wall. The insulating patch 80 is connected to the wall of the housing 301 through the adhesive structure.

[0153] In some feasible ways, Figure 14 A partial structure of the insulating patch 80 is shown schematically. Figure 15 A partial exploded view of the insulating patch 80 is schematically shown. See also Figure 14 and Figure 15 As shown, the insulating patch 80 also includes an adhesive layer 200. The insulating layer 90, the composite layer 100, and the adhesive layer 200 are stacked. The adhesive layer 200 is disposed on the side of the composite layer 100 opposite to the insulating layer 90. The adhesive layer 200 is bonded to the wall of the housing 301.

[0154] When connecting the insulating patch 80 to the wall of the housing 301, the insulating patch 80 can be adhered to the outer surface 40a of the wall via the adhesive layer 200 to fix the position of the insulating patch 80. The connection method between the insulating patch 80 and the wall of the housing 301 is simple and easy to operate, reducing the difficulty of connecting the insulating patch 80 to the wall of the housing 301. The adhesive layer 200 can be a thermally conductive material, which does not affect the heat conduction effect between the insulating patch 80 and the wall of the housing 301.

[0155] The adhesive layer 200 can effectively fill the gap between the composite layer 100 and the wall of the outer shell 301. On the one hand, it reduces the possibility that the thermal conductivity between the composite layer 100 and the wall of the outer shell 301 will be affected by the air gap between them. On the other hand, it ensures that the connection area between the insulating patch 80 and the wall of the outer shell 301 is large, reducing the possibility that the connection force between the insulating patch 80 and the wall of the outer shell 301 will decrease due to the gap between them.

[0156] In some examples, the adhesive layer 200 can be double-sided tape or adhesive. Exemplarily, release paper is adhered to the adhesive layer 200 before the insulating patch 80 is used. The release paper protects the adhesive layer 200, effectively preventing it from being contaminated by dust or other dirt. When connecting the insulating patch 80 to the wall of the housing 301, the release paper is removed first, and then the insulating patch 80 is adhered to the outer surface 40a of the wall.

[0157] See also some of the possible implementation methods. Figure 14As shown, an obstacle avoidance hole 801 is provided on the insulating patch 80 in the area corresponding to the first layer 101. The obstacle avoidance hole 801 penetrates two opposite surfaces of the insulating patch 80. The obstacle avoidance hole 801 penetrates the insulating layer 90 and the composite layer 100. The electrode terminal 41 passes through the obstacle avoidance hole 801 of the insulating patch 80. The first layer 101 is disposed around the electrode terminal 41, so that the first layer 101 can dissipate heat from various positions around the electrode terminal 41, which is beneficial to improving the heat dissipation effect of the insulating patch 80. In some examples, the insulating patch 80 also includes an adhesive layer 200. The obstacle avoidance hole 801 penetrates the insulating layer 90, the composite layer 100, and the adhesive layer 200.

[0158] In some feasible ways, Figure 16 A partial disassembled structure of the battery cell 30 is schematically shown. See also Figure 16 As shown, the battery cell 30 also includes a pressure relief component 70. The pressure relief component 70 is used to release internal pressure when the internal pressure or temperature of the battery cell 30 reaches a threshold. The pressure relief component 70 is disposed on the wall of the housing 301. A second layer 102 is disposed corresponding to the pressure relief component 70. The second layer 102 shields at least a portion of the pressure relief component 70.

[0159] The second layer 102 can protect the pressure relief component 70. When the external ambient temperature of the battery cell 30 is relatively high, the second layer 102 can effectively isolate external heat from being conducted to the pressure relief component 70. This helps reduce the possibility of external heat being rapidly transferred to the pressure relief component 70 and causing it to heat up rapidly in a short time. This reduces the possibility of the pressure relief component 70 melting in a short time due to rapid temperature rise or the rapid conduction of heat into the battery cell 30 through the pressure relief component 70. Consequently, it reduces the possibility of thermal runaway of the battery cell 30 due to melting of the pressure relief component 70 or rapid heating of the battery cell 30.

[0160] For example, in a battery module comprising multiple battery cells 30, when one battery cell 30 experiences thermal runaway, the high-temperature material ejected from that cell is more likely to affect other normal battery cells 30 in the vicinity. Since adjacent battery cells 30 include insulating patches 80, the second layer 102 within the insulating patches 80 can effectively isolate the heat generated by the high-temperature material from being conducted to the pressure relief component 70. This helps reduce the likelihood of normal battery cells 30 also experiencing thermal runaway, effectively improving the safety of the battery module.

[0161] In some examples, the second layer 102 can shield the entire pressure relief element 70. Along the thickness direction Z of the insulating patch 80, the orthographic projection of the pressure relief element 70 lies within the orthographic projection of the second layer 102.

[0162] In some examples, the second layer 102 can be a thermal insulation material layer, which helps to further reduce the rate at which external heat is conducted to the pressure relief component 70 when the external ambient temperature is relatively high.

[0163] In some examples, the second layer 102 includes a first sublayer 1021 and a second sublayer 1022. The first sublayer 1021 shields at least part of the pressure relief element 70, while the second sublayer 1022 does not shield the pressure relief element 70. The first sublayer 1021 may be a layer of thermal insulation material.

[0164] In some examples, Figure 17 A partial structure of the insulating patch 80 is schematically shown. See also Figure 17 As shown, an annular groove 802 is provided on the insulating patch 80 in the area corresponding to the second layer 102. The annular groove 802 is a continuously extending groove. Along the thickness direction Z of the insulating patch 80, the annular groove 802 does not penetrate the insulating patch 80. The insulating patch 80 is a region where the thickness is reduced at the annular groove 802. When the pressure relief component 70 is opened to release the internal pressure of the battery cell 30, the insulating patch 80 is subjected to an impact force, and the insulating patch 80 is prone to breakage at the annular groove 802, thereby ensuring that the insulating patch 80 does not affect the normal pressure relief of the pressure relief component 70, reducing the possibility of the battery cell 30 exploding due to poor pressure relief of the pressure relief component 70. For example, along the thickness direction Z of the insulating patch 80, the orthographic projection of the pressure relief component 70 is located within the orthographic projection of the annular groove 802.

[0165] In some examples, Figure 18 A partial structure of the insulating patch 80 is schematically shown. See also Figure 18 As shown, multiple scribe lines 803 are provided on the insulating patch 80 in the area corresponding to the second layer 102. The multiple scribe lines 803 are arranged in a ring at intervals. The scribe lines 803 can be recessed. Along the thickness direction Z of the insulating patch 80, the scribe lines 803 do not penetrate the insulating patch 80. The insulating patch 80 is a thinner region at the scribe lines 803. Any two adjacent scribe lines 803 are not connected. When the pressure relief component 70 opens to release the internal pressure of the battery cell 30, the insulating patch 80 is subjected to an impact force, and the insulating patch 80 is prone to breakage at the scribe lines 803, thereby ensuring that the insulating patch 80 does not affect the normal pressure relief of the pressure relief component 70, reducing the possibility of the battery cell 30 exploding due to poor pressure relief by the pressure relief component 70. For example, along the thickness direction Z of the insulating patch 80, the orthographic projections of each scribe line 803 are distributed around the orthographic projection of the pressure relief component 70.

[0166] In some examples, Figure 19 A partial structure of the insulating patch 80 is schematically shown. See also Figure 19As shown, the insulating patch 80 has multiple through holes 804 in the area corresponding to the second layer 102. The multiple through holes 804 are arranged in a ring-shaped interval. Along the thickness direction Z of the insulating patch 80, the through holes 804 penetrate the insulating patch 80. The through holes 804 penetrate the insulating layer 90 and the composite layer 100. Any two adjacent through holes 804 are not connected. When the pressure relief component 70 opens to release the internal pressure of the battery cell 30, the insulating patch 80 is subjected to an impact force, and the insulating patch 80 is prone to breakage in the area where the through holes 804 are located. This ensures that the insulating patch 80 does not affect the normal pressure relief of the pressure relief component 70, reducing the possibility of the battery cell 30 exploding due to poor pressure relief by the pressure relief component 70. For example, along the thickness direction Z of the insulating patch 80, the orthographic projections of each through hole 804 are distributed around the orthographic projection of the pressure relief component 70.

[0167] See in some examples Figure 19 As shown, a first window 805 and a second window 806 are provided on the insulating patch 80 in the area corresponding to the second layer 102. The first window 805 and the second window 806 penetrate the insulating patch 80 along its thickness direction Z. The first window 805 and the second window 806 penetrate the insulating layer 90 and the composite layer 100. The first window 805 is provided for a sealing pin used to seal the injection hole. The first window 805 can avoid the sealing pin, so that there is no positional interference between the insulating patch 80 and the sealing pin. The second window 806 corresponds to the inkjet printing area on the wall of the outer casing 301. The second window 806 can avoid the inkjet printing area, so that the insulating patch 80 does not obstruct the inkjet printing area. The first window 805 and the second window 806 are located on opposite sides of the pressure relief component 70.

[0168] For example, the second layer 102 includes a first sublayer 1021 and a second sublayer 1022. The insulating patch 80 has a first window 805 and a second window 806 in the area corresponding to the second sublayer 1022.

[0169] In some feasible implementations, two electrode terminals 41 are disposed on the wall of the housing 301. A pressure relief element 70 is located between the two electrode terminals 41. The composite layer 100 includes two first layers 101. A second layer 102 is disposed between the two first layers 101. The two first layers 101 respectively dissipate heat from the two electrode terminals 41. The area on the wall of the housing 301 between the two electrode terminals 41 is relatively large. The second layer 102 can shield the area on the wall of the housing 301 between the two electrode terminals 41, thereby mitigating the conduction of external heat to the battery cell 30 through the area between the two electrode terminals 41 when the external ambient temperature is relatively high.

[0170] In some examples, the second layer 102 includes a first sublayer 1021 and two second sublayers 1022. A first sublayer 1021 has a second sublayer 1022 disposed on each side opposite to it.

[0171] In some examples, the outer contour of the wall of housing 301 is rectangular. The outer contour of insulating patch 80 is rectangular.

[0172] According to some embodiments of this application, this application also provides a battery device 10, including a battery cell 30 of any of the above schemes.

[0173] According to some embodiments of this application, this application also provides an electrical device including a battery device 10 of any of the above schemes, and the battery device 10 is used to provide electrical energy to the electrical device.

[0174] The power supply device can be any of the aforementioned devices or systems that utilize battery device 10.

[0175] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: The outer shell, including the walls; Electrode terminals are disposed on the wall. An insulating patch is disposed on the outer surface of the wall. The insulating patch includes an insulating layer and a composite layer stacked on top of each other. The composite layer includes a first layer and a second layer. The thermal conductivity of the first layer is greater than that of the second layer. The first layer is disposed corresponding to the electrode terminal.

2. The battery cell according to claim 1, characterized in that, At least a portion of the composite layer is disposed on the side of the insulating layer facing the wall.

3. The battery cell according to claim 1 or 2, characterized in that, The first layer and the second layer are connected.

4. The battery cell according to any one of claims 1 to 3, characterized in that, The thickness of the first layer is greater than the thickness of the second layer.

5. The battery cell according to any one of claims 1 to 4, characterized in that, The second layer is a heat insulation material layer, and the material of the second layer is different from that of the insulating layer.

6. The battery cell according to any one of claims 1 to 4, characterized in that, The material of the second layer is the same as that of the insulating layer, and the second layer and the insulating layer are integrally formed.

7. The battery cell according to any one of claims 1 to 4, characterized in that, The second layer includes a first sublayer and a second sublayer, which are connected to the first layer. The thermal conductivity of the second sublayer is greater than that of the first sublayer.

8. The battery cell according to claim 7, characterized in that, The first sublayer is a thermal insulation material layer, and the materials of the first layer, the first sublayer, and the second sublayer are different.

9. The battery cell according to claim 7 or 8, characterized in that, The material of the second sublayer is the same as that of the insulating layer, and the second sublayer and the insulating layer are integrally formed.

10. The battery cell according to any one of claims 1 to 9, characterized in that, The insulating layer includes a first insulating segment and a second insulating segment. The first layer is disposed on the first insulating segment to form a first sub-pattern, and the second layer is disposed on the second insulating segment to form a second sub-pattern. The first sub-pattern and the second sub-pattern are spliced ​​together to form the insulating patch.

11. The battery cell according to any one of claims 1 to 10, characterized in that, The thermal conductivity of the first layer is greater than or equal to 5 W / m·°C, and the thermal conductivity of the second layer is less than or equal to 1 W / m·°C.

12. The battery cell according to any one of claims 1 to 11, characterized in that, The insulating patch has a clearance hole in the area corresponding to the first layer, and the electrode terminal passes through the clearance hole.

13. The battery cell according to any one of claims 1 to 12, characterized in that, The battery cell also includes a pressure relief component, which is disposed on the wall. The second layer is disposed corresponding to the pressure relief component, and the second layer blocks at least a portion of the pressure relief component.

14. The battery cell according to claim 13, characterized in that, The insulating patch has annular grooves in the area corresponding to the second layer; or... The insulating patch has multiple etched lines in the area corresponding to the second layer, and these etched lines are arranged in a ring at intervals; or... The insulating patch has multiple through holes in the area corresponding to the second layer, and the multiple through holes are arranged in a ring at intervals.

15. The battery cell according to claim 13 or 14, characterized in that, Two electrode terminals are provided on the wall, and the pressure relief component is located between the two electrode terminals. The composite layer includes two first layers, and a second layer is provided between the two first layers.

16. The battery cell according to any one of claims 1 to 15, characterized in that, The insulating patch further includes an adhesive layer. The insulating layer, the composite layer, and the adhesive layer are stacked together. The adhesive layer is disposed on the side of the composite layer opposite to the insulating layer, and the adhesive layer is bonded to the wall.

17. The battery cell according to any one of claims 1 to 16, characterized in that, The outer casing includes a housing and an end cap, the end cap being connected to the housing and serving as the wall.

18. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 17.

19. An electrical appliance, characterized in that, Includes the battery device as described in claim 18, the battery device being used to provide electrical energy.

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