Battery module, battery pack, and electric device

Abstract

The present disclosure is applicable to the technical field of batteries, and provides a battery module, a battery pack, and an electric device. The electric device comprises the battery pack, the battery pack comprises the battery module, the battery module comprises one or more battery units, and each battery unit comprises at least one heat conduction structure and at least two battery cells stacked in a first direction. The heat conduction structure is at least partially arranged between two adjacent battery cells in the first direction. The thermal conductivity of the heat conduction structure in the first direction is smaller than that in a direction perpendicular to the first direction. The present disclosure can quickly decrease the temperature at the center position of each battery cell, reduce the heat effect of the battery cell on the adjacent battery cell stacked in the first direction, reduce the probability of thermal runaway, and thus reduce the risk of failure of the whole battery module caused by thermal diffusion between the battery cells.

Description

Battery module, battery pack and power-consuming device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure is based on the Chinese patent application with application number 202420613822.6, application date March 27, 2024, and invention name “A battery module, battery pack and electrical device”, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into the present disclosure as a reference. Technical Field

[0003] The present disclosure belongs to the field of battery technology, and in particular relates to a battery module, a battery pack and an electrical device. Background Art

[0004] With the rapid development of the energy storage market in recent years, the energy density requirements for battery modules have become increasingly higher. In related technologies, battery modules use bottom-side cooling to dissipate heat from the battery cells. However, this cooling method results in higher temperatures at locations farther from the heat dissipation interface, particularly in the center of the interface between adjacent cells. This extreme center temperature can cause nearby active materials to reach an instability point, leading to thermal diffusion and ultimately failure of the entire battery module.

[0005] Summary of the Invention

[0006] In view of this, the embodiments of the present disclosure hope to provide a battery module, a battery pack and an electrical device, which are designed to quickly reduce the temperature at the center of the battery cell, reduce the thermal impact of the battery cell on the adjacent battery cells stacked along the first direction, reduce the probability of thermal runaway, and thus reduce the risk of heat diffusion between the battery cells leading to failure of the entire battery module.

[0007] In a first aspect, an embodiment of the present disclosure provides a battery module, comprising:

[0008] One or more battery cells, each battery cell comprising at least one heat-conducting structure and at least two battery cells stacked along a first direction;

[0009] The heat-conducting structure is at least partially disposed between two adjacent battery cells along the first direction;

[0010] The thermal conductivity of the heat-conducting structure along the first direction is smaller than the thermal conductivity in a direction perpendicular to the first direction.

[0011] The battery module provided by the embodiment of the present disclosure rapidly transfers heat from the center position of the contact surface of the battery cell in contact with the heat-conducting structure to other positions of the contact surface of the battery cell through the heat-conducting structure, thereby reducing the temperature at the center position of the battery cell and thus reducing the probability of thermal runaway. In addition, because the thermal conductivity coefficient of the heat-conducting structure along the first direction is lower than the thermal conductivity coefficient in the direction perpendicular to the first direction, the thermal impact of the battery cell on the adjacent battery cells stacked along the first direction is reduced, thereby reducing the risk of failure of the entire battery module due to heat diffusion between the battery cells.

[0012] In some embodiments, a ratio of a thermal conductivity of the heat-conducting structure along a direction perpendicular to the first direction to a thermal conductivity along the first direction is greater than or equal to 4.

[0013] Such an arrangement enables the heat-conducting structure to conduct heat quickly in a direction perpendicular to the first direction, and also reduces the thermal impact of the battery cells on adjacent battery cells stacked in the first direction.

[0014] In some embodiments, the heat-conducting structure is a sheet-like structure and is sandwiched between two adjacent battery cells.

[0015] With such arrangement, the heat-conducting structure has a simple structure, is easy to manufacture, and facilitates the orderly stacking of battery cells along the first direction.

[0016] In some embodiments, the sheet structure includes a heat insulating layer and at least two heat conducting layers, each heat conducting layer is disposed on opposite sides of the heat insulating layer along a first direction, and the thermal conductivity of the heat conducting layer is greater than that of the heat insulating layer.

[0017] With this arrangement, the heat-conducting layer can quickly transfer the temperature of the center of the battery cell to the surrounding area of ​​the center of the battery cell. Since the heat-insulating layer is located in the middle of the heat-conducting layer, the thermal impact of the battery cell on the adjacent battery cells stacked along the first direction is reduced.

[0018] In some embodiments, the sheet structure further includes an insulating layer and an adhesive layer. The insulating layer is disposed on the side of the thermally conductive layer away from the thermal insulation layer, and the adhesive layer is disposed on the side of the insulating layer away from the thermally conductive layer for bonding to the battery cells. The insulating layer provides good electrical insulation for the thermally conductive structure. The adhesive layer is used to bond the thermally conductive structure to the battery cells, ensuring a more reliable fit and better heat transfer.

[0019] In some embodiments, the thickness of the heat conductive layer is 0.5 mm to 1 mm. This arrangement can maintain a suitable spacing between two adjacent battery cells, making the battery module structure compact and saving battery module space while ensuring heat dissipation.

[0020] In some embodiments, the thermal insulation layer has pores to allow it to compress under the pressure of two adjacent battery cells in a first direction. With this arrangement, when the battery module is subjected to vibration or expansion, the two adjacent battery cells squeeze the heat-conductive structure in the first direction. Because the thermal insulation layer has pores, it compresses under the pressure, reducing the squeezing force between adjacent battery cells and thereby enhancing the safety performance of the battery module.

[0021] In some embodiments, the thermal insulation layer is any one or more of foam, rubber, ceramic fiber, glass fiber, and aerogel, so that the thermal insulation layer has good thermal insulation effect and compression performance.

[0022] In some embodiments, there are multiple battery cells, arranged side by side along the second direction, with at least one sheet-like structure extending between two adjacent battery cells of another battery cell, so that at least two adjacent battery cells along the second direction share the sheet-like structure. This arrangement allows the sheet-like structure to rapidly transfer heat from the center of the contact surface of the battery cell in contact with the sheet-like structure to the battery cells sharing the sheet-like structure. By sharing heat between adjacent battery cells along the second direction, cooling can be further accelerated.

[0023] In some embodiments, the thickness of the heat-conducting structure along the first direction is 0.2 mm to 5 mm. This arrangement can maintain a suitable spacing between two adjacent battery cells, making the battery module structure compact and saving battery module space while ensuring heat dissipation.

[0024] In some embodiments, the battery module includes a cold plate, the battery cells are arranged on the cold plate, the cold plate has a groove, and one end of the sheet structure is inserted into the groove.

[0025] With this arrangement, the battery cells transfer heat to the cold plate through the sheet structure, effectively improving the heat exchange efficiency between the battery cells and the cold plate, giving full play to the cooling effect of the cold plate, making the heat exchange effect of the battery cells better, the heat dissipation of the battery cells more efficient, and helping to increase the service life of the battery cells.

[0026] In some embodiments, the heat-conducting structure is a casing structure having a housing space, wherein the battery cell has a pole at a first end along the height direction, and the housing space has an opening at at least one end along the height direction. The battery cell is at least partially housed in the housing space, and the first end of the battery cell is exposed at the opening. The housing space of the casing structure is used to house the battery cell, and the housing space has an opening at at least one end along the height direction, facilitating the housing of the battery cell within the casing structure. Because the casing structure has multiple surfaces in contact with the battery cell, heat at the center of the contact surface of the stacked battery cells along the first direction can be rapidly transferred to other locations of the battery cell through the casing structure, thereby rapidly reducing the temperature at the center of the contact surface of the battery cell.

[0027] In some embodiments, the casing structure is sealed at locations other than the opening, thereby ensuring heat conduction while also facilitating reliable connection between the casing structure and the battery cell.

[0028] In some embodiments, the casing structure has a notch on at least one side along the second direction, wherein the second direction, the first direction, and the height direction are perpendicular to each other.

[0029] In some embodiments, the thickness of the casing structure is 0.02 mm to 0.5 mm. In this embodiment, the thickness of the casing structure within this range can ensure the structural strength of the casing structure while maintaining a suitable spacing between two adjacent battery cells, making the battery module structure compact and saving battery module space.

[0030] In some embodiments, the casing structure comprises, from the inside out, a first adhesive film layer, a thermally conductive layer, a second adhesive film layer, and an insulating film layer. The first adhesive film layer is bonded to the battery cells, while the thermally conductive layer and the insulating layer are bonded via the second adhesive film layer. The first adhesive film layer is bonded to the battery cells and the thermally conductive layer, securing the thermally conductive layer to the corresponding battery cells. The insulating layer provides insulation for the casing structure, and the second adhesive film layer is disposed between the thermally conductive layer and the insulating layer, securing the insulating layer to the thermally conductive layer. This arrangement ensures both the thermal conductivity and the insulating performance of the casing structure.

[0031] In a second aspect, an embodiment of the present disclosure provides a battery pack, comprising the battery module of any embodiment of the present disclosure.

[0032] The battery pack provided by the embodiment of the present disclosure, by adopting the battery module involved above, can quickly reduce the temperature at the center of the battery cell, reduce the thermal impact of the battery cell on the adjacent battery cells stacked along the first direction, reduce the probability of thermal runaway, and thus reduce the risk of heat diffusion between the battery cells causing failure of the entire battery module.

[0033] The electrical device provided by the embodiments of the present disclosure, by employing the battery module or battery pack described above, can rapidly reduce the temperature at the center of a battery cell, minimizing the thermal impact of a battery cell on adjacent battery cells stacked along a first direction, lowering the probability of thermal runaway, and thereby reducing the risk of heat diffusion between battery cells leading to failure of the entire battery module. This results in the electrical device having lower cost and higher reliability.

[0034] The above description is only an overview of the technical solution of the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific implementation methods of the present disclosure are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a schematic diagram of a partial structure of a battery module provided in some embodiments of the present disclosure;

[0036] FIG2 is a schematic diagram of a sheet-like heat-conducting structure and an adjacent battery cell provided in some embodiments of the present disclosure;

[0037] FIG3 is a schematic diagram of the composition structure of a sheet-like heat-conducting structure provided by some embodiments of the present disclosure;

[0038] FIG4 is a top view of FIG1 ;

[0039] FIG5 is a cross-sectional view along AA of FIG4 in the case where the cold plate has a groove structure;

[0040] FIG6 is a partial enlarged view of point B of the cross-sectional view along line AA in FIG4 in the case where the cold plate has a groove structure;

[0041] FIG7 is a cross-sectional view along AA of FIG4 in the case where the cold plate does not have a groove structure;

[0042] FIG8 is a partial enlarged view of point C of the cross-sectional view along line AA in FIG4 when the cold plate does not have a groove structure;

[0043] FIG9 is a schematic diagram of a casing structure and a battery cell provided in some embodiments of the present disclosure, wherein one side is open in the height direction and the rest of the structure is sealed;

[0044] FIG10 is a schematic diagram of a casing structure and a battery cell having a notch on at least one side along the second direction provided by some embodiments of the present disclosure;

[0045] FIG11 is a schematic diagram of a casing structure and a battery cell with openings on both sides in the height direction provided by some embodiments of the present disclosure;

[0046] FIG12 is a schematic diagram of the composition structure of the shell structure provided in some embodiments of the present disclosure.

[0047] Description of reference numerals:

[0048] 1000, battery cell; 2000, cold plate; 2100, groove; 100, battery cell; 110, pole; 200, heat-conducting structure; 210, sheet structure; 211, heat-conducting layer; 212, heat-insulating layer; 213, insulating layer; 214, adhesive layer; 220, casing structure; 221, first adhesive film layer; 222, heat-conducting film layer; 223, second adhesive film layer; 224, insulating film layer; 225, accommodating space; 226, opening; 227, notch; 300, thermally conductive adhesive; L1, thickness of the heat-conducting layer; L2, thickness of the heat-conducting structure; L3, thickness of the casing structure; W1, first direction; W2, second direction. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0050] The various specific technical features described in the specific embodiments may be combined in any suitable manner, unless they are inconsistent. For example, different embodiments and technical solutions may be formed by combining different specific technical features. To avoid unnecessary repetition, the various possible combinations of the specific technical features in the present invention will not be described separately.

[0051] In the following description, the terms "first, second, ..." are used solely to distinguish different objects and do not imply any similarities or connections between the objects. It should be understood that the directions "above," "below," "outside," and "inside" refer to directions during normal use. The directions "left" and "right" refer to the left-right directions shown in the corresponding schematic diagrams, which may or may not be the left-right directions during normal use.

[0052] It should be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus comprising that element. "A plurality" means greater than or equal to two.

[0053] Currently, new energy batteries are increasingly being used in everyday life and industry. They are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in other fields. As the application of power batteries continues to expand, market demand is also growing.

[0054] In related technologies, battery modules use bottom heat dissipation to dissipate heat from battery cells. However, this heat dissipation method causes the temperature of battery cells farther away from the heat dissipation interface to be higher, especially the temperature of the central area of ​​the contact surface between two adjacent battery cells. The extreme temperature of the central area may cause the internal active materials to reach the instability point and cause heat diffusion, ultimately leading to the failure of the entire battery module.

[0055] In view of the above problems, an embodiment of the present disclosure provides a battery module, comprising one or more battery cells, each battery cell comprising at least one heat-conducting structure and at least two battery cells stacked along a first direction. At least part of the heat-conducting structure is arranged between two adjacent battery cells along the first direction. The thermal conductivity of the heat-conducting structure along the first direction is less than the thermal conductivity in the direction perpendicular to the first direction. In this way, the heat at the center position of the contact surface of the battery cell in contact with the heat-conducting structure is quickly transferred to other positions of the contact surface of the battery cell through the heat-conducting structure, thereby reducing the temperature at the center position of the battery cell and thus reducing the probability of thermal runaway. In addition, since the thermal conductivity of the heat-conducting structure along the first direction is less than the thermal conductivity in the direction perpendicular to the first direction, the thermal influence of the battery cell on the adjacent battery cells stacked along the first direction is reduced, thereby reducing the risk of failure of the entire battery module due to heat diffusion between the battery cells.

[0056] An embodiment of the present disclosure provides a battery pack, which includes the above-mentioned battery module.

[0057] The present disclosure also provides an electrical device comprising the aforementioned battery module or battery pack. The battery module or battery pack can provide electrical energy to the electrical device. The electrical device can include, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, and the like. The electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the spacecraft can include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0058] In the following embodiments, for the convenience of description, an electric vehicle according to an embodiment of the present disclosure is taken as an example.

[0059] The vehicle can be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The latter can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. The vehicle is equipped with a battery, which can be located at the bottom, front, or rear of the vehicle. The battery can be used to power the vehicle, for example, as a power source for operation. The vehicle may also include a controller and a motor. The controller controls the battery to power the motor, for example, for starting the vehicle, navigation, and operating power requirements during driving.

[0060] In some embodiments of the present disclosure, the battery can serve not only as the operating power source of the vehicle, but also as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0061] An embodiment of the present disclosure provides a battery module, as shown in FIG1 . The battery module includes one or more battery cells 1000 . A battery cell 1000 includes at least one thermally conductive structure 200 and at least two battery cells 100 stacked along a first direction W1. At least a portion of the thermally conductive structure 200 is disposed between two adjacent battery cells 100 along the first direction W1. The thermal conductivity of the thermally conductive structure 200 along the first direction W1 is lower than the thermal conductivity in a direction perpendicular to the first direction W1.

[0062] In FIG1 , the structure within the dotted box illustrates a battery unit 1000 . It is understandable that, in the embodiment of the present disclosure, the number of battery units 1000 may be one, two, or more than two.

[0063] A battery cell 100 is the basic device and unit that directly converts chemical energy into electrical energy. It is the fundamental component of a battery. Its components include electrolyte, positive and negative electrodes, and a separator. A battery cell 100 is also the smallest unit in a power battery module.

[0064] For example, the battery cell 100 includes a housing and an electrode assembly, wherein the electrode assembly is disposed in the housing. The housing is an external structural component of the battery cell 100.

[0065] The electrode assembly is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies may be contained in the housing. The electrode assembly is mainly formed by winding pole sheets (positive pole sheets and negative pole sheets), and a separator is usually provided between the positive pole sheet and the negative pole sheet. The portion of the pole sheet (positive pole sheet and negative pole sheet) having the active material constitutes the main body of the electrode assembly, and the main body is connected to the tabs. The positive pole tab and the negative pole tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tabs are connected to the pole column 110 to form a current loop.

[0066] The housing is the component that isolates the internal environment of the battery cell 100 from the external environment. The housing can be made of a material with a certain degree of hardness and strength (such as aluminum alloy). This prevents the housing from deforming during compression or collision, giving the battery cell 100 greater structural strength and improved safety.

[0067] The heat-conducting structure 200 is a medium for transferring heat and is in contact with the surface of the battery cell 100 to transfer the heat generated by the battery cell 100 .

[0068] Thermal conductivity, also known as thermal conductivity or thermal conductivity, is an important physical quantity that measures a material's ability to conduct heat. It is defined as the amount of heat transferred per unit time through one square meter of surface area under stable heat transfer conditions, when the material is one meter thick and the temperature difference between the two surfaces is one degree (K or °C). The unit of thermal conductivity is typically Watts per meter per Kelvin (W / (m·K)), sometimes also expressed in the International System of Units (SI) of Joules per square meter of Kelvin (J / (m·K)). The magnitude of the thermal conductivity has a significant impact on the material's thermal insulation or heat dissipation properties. For example, materials with low thermal conductivity excel at insulation, while materials with high thermal conductivity are suitable for applications requiring rapid heat transfer.

[0069] In the battery module of the disclosed embodiment, the heat at the center of the contact surface of the battery cell 100 in contact with the heat-conducting structure 200 is quickly transferred to other positions of the contact surface of the battery cell 100 through the heat-conducting structure 200, thereby reducing the temperature at the center of the battery cell 100 and thus reducing the probability of thermal runaway. In addition, because the thermal conductivity of the heat-conducting structure 200 along the first direction W1 is lower than the thermal conductivity in the direction perpendicular to the first direction W1, the thermal impact of the battery cell 100 on the adjacent battery cells 100 stacked along the first direction W1 is reduced, thereby reducing the risk of failure of the entire battery module due to heat diffusion between the battery cells 100.

[0070] In the disclosed embodiment, taking rectangular battery cells 100 as an example, the large surfaces of the battery cells 100 in a group are stacked together, and the small surfaces of the two groups of battery cells 100 are aligned. In other words, the first direction W1 is parallel to the arrangement direction of the large surfaces of the battery cells 100, and the second direction W2 is parallel to the arrangement direction of the small surfaces of the battery cells 100.

[0071] In some embodiments, the ratio of the thermal conductivity of the heat-conducting structure 200 along the direction perpendicular to the first direction W1 to the thermal conductivity along the first direction W1 is greater than or equal to 4. This configuration allows the heat-conducting structure 200 to conduct heat rapidly along the direction perpendicular to the first direction W1 and reduces the thermal impact of the battery cells 100 on adjacent battery cells 100 stacked along the first direction W1.

[0072] The specific shape of the heat conducting structure 200 is not limited.

[0073] For example, in some embodiments, referring to FIG2 , the heat conducting structure 200 is a sheet-like structure 210 and is sandwiched between two adjacent battery cells 100. This configuration makes the heat conducting structure 200 simple and easy to manufacture, and facilitates neat stacking of the battery cells 100 along the first direction.

[0074] The sheet structure 210 may be a single-layer structure, a double-layer composite structure, a three-layer composite structure, or a multi-layer composite structure.

[0075] In embodiments where the sheet structure 210 is a single-layer structure, the sheet structure 210 may be made of a material with anisotropic thermal conductivity, such as graphite. In other words, the microscopic physical properties of the material itself result in a thermal conductivity along a first direction W1 that is lower than the thermal conductivity in a direction perpendicular to the first direction W1. For example, in embodiments where the sheet structure 210 is a single-layer structure, the thermal conductivity of the thermally conductive structure along the first direction is ≤100 W / (m*K), and the thermal conductivity along a direction perpendicular to the first direction is ≥400 W / (m*K).

[0076] For example, in some embodiments, referring to FIG. 3 , the sheet structure 210 includes a thermal insulation layer 212 and at least two thermally conductive layers 211 . Each thermally conductive layer 211 is disposed on opposite sides of the thermal insulation layer 212 along a first direction W1, and the thermal conductivity of the thermally conductive layer 211 is greater than the thermal conductivity of the thermal insulation layer 212. That is, in this embodiment, the sheet structure 210 is at least a three-layer composite structure. In this embodiment, it can be made of a metal sheet, aluminum nitride, silicon carbide, or other materials. The difference in thermal conductivity between the sheet structure 210 in the first direction and perpendicular to the first direction can be achieved by the thermal insulation layer 212. The thermal insulation effect of the thermal insulation layer 212 causes the thermal conductivity of the thermally conductive structure 200 in the first direction to be less than the thermal conductivity perpendicular to the first direction.

[0077] With this arrangement, the heat conductive layer 211 can quickly transfer the temperature of the center of the battery cell 100 to the surrounding area of ​​the center of the battery cell 100. Since the heat insulating layer 212 is located in the middle of the heat conductive layer 211, the heat impact of the battery cell 100 on the adjacent battery cells 100 stacked along the first direction W1 is reduced.

[0078] The insulation layer 212 is made of a heat-insulating material, also known as a thermal insulation material, which can block the transfer of heat flow, such as glass fiber, asbestos, rock wool, foam, silicate, vacuum board, rubber, ceramic fiber, aerogel, etc.

[0079] The material of the heat-conducting layer 211 can be a material with heat-conducting properties, and the heat-conducting coefficient of the heat-conducting layer 211 is the same along any direction, such as metal sheet, aluminum nitride, silicon carbide, etc.

[0080] Exemplarily, the thermal conductivity of the heat-conducting layer 211 is ≥200 W / (m*K).

[0081] In some embodiments, the sheet structure 210 further includes an insulating layer 213 and an adhesive layer 214. The insulating layer 213 is disposed on the side of the thermally conductive layer 211 away from the thermal insulation layer 212, and the adhesive layer 214 is disposed on the side of the insulating layer 213 away from the thermally conductive layer 211 for bonding to the battery cell 100. In other words, in this embodiment, the sheet structure 210 is a composite structure of at least five layers.

[0082] The insulating layer 213 can provide good electrical insulation for the heat-conducting structure 200. The adhesive layer 214 is used to bond the heat-conducting structure 200 to the battery cell 100, making the bonding between the two more reliable and improving the heat transfer effect.

[0083] The insulating layer 213 is made of insulating material that is non-conductive under the allowable voltage, such as polyvinyl chloride, polyethylene, polypropylene, polyester, natural rubber, artificial rubber, silicone rubber, insulating oil, insulating varnish, insulating adhesive, etc.

[0084] The material of the bonding layer 214 is adhesive, for example, it can be copper oxide phosphate, white latex, polyimide-based adhesive, phenolic resin adhesive, acrylaldehyde-based adhesive, polyurethane adhesive, epoxy resin adhesive, cyanoacrylate adhesive, anaerobic adhesive, inorganic adhesive, hot melt adhesive, etc.

[0085] In some embodiments, the thickness L1 of the heat conductive layer 211 is 0.5 mm to 1 mm (millimeter). For example, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc. This arrangement can maintain an appropriate spacing between two adjacent battery cells 100, making the battery module structure compact and saving battery module space while ensuring heat dissipation.

[0086] The thickness L1 of the heat-conducting layer 211 refers to the maximum dimension of the heat-conducting layer 211 along the first direction. When measuring, the distance between the insulating layer 213 and the heat-insulating layer 212 can be measured, and this distance can be regarded as the thickness of the heat-conducting layer 211.

[0087] In some embodiments, the thermal insulation layer 212 has pores, allowing it to compress when squeezed along the first direction W1 by two adjacent battery cells 100. With this arrangement, when the battery module is subjected to vibration or expansion, the two adjacent battery cells 100 squeeze the thermal conductive structure 200 along the first direction W1. Because the thermal insulation layer has pores, it compresses under the squeeze force, reducing the squeezing force between adjacent battery cells 100 and thereby enhancing the safety performance of the battery module.

[0088] In some embodiments, the thermal insulation layer 212 may be made of any one or more of foam, rubber, ceramic fiber, glass fiber, and aerogel, so that the thermal insulation layer 212 has good thermal insulation effect and compression performance.

[0089] Exemplarily, the dimension of the sheet structure 210 along the second direction is not less than 90% of the dimension of the battery cell 100 along the second direction, so that the sheet structure 210 and the battery cell 100 have sufficient contact area, thereby ensuring the heat conduction effect.

[0090] The number of battery cells 1000 may be one or more.

[0091] In some embodiments, there are multiple battery cells 1000, and the multiple battery cells 1000 are arranged side by side along the second direction W2. At least one sheet structure 210 extends between two adjacent battery cells 100 of another battery cell 1000, so that at least two adjacent battery cells 1000 along the second direction W2 share the sheet structure 210. With this arrangement, the sheet structure 210 rapidly transfers heat from the center of the contact surface of the battery cell 100 in contact with the sheet structure 210 to the battery cells 100 that share the sheet structure 210. By sharing heat between adjacent battery cells along the second direction, cooling can be further accelerated.

[0092] In some embodiments, the thickness of the sheet structure 210 along the first direction W1 is 0.2 mm to 5 mm, for example, 0.2 mm, 0.6 mm, 1 mm, 1.4 mm, 1.8 mm, 2.2 mm, 2.6 mm, 3 mm, 3.4 mm, 3.8 mm, 4.2 mm, 4.6 mm, 5 mm, etc. This arrangement maintains an appropriate spacing between adjacent battery cells 100, making the battery module structure compact and saving battery module space while ensuring effective heat dissipation.

[0093] The thickness L2 of the heat-conducting structure 200 refers to the maximum dimension of the heat-conducting structure 200 along its thickness direction. When measuring, the distance between the large surfaces of two adjacent battery cells 100 can be measured, and this distance can be regarded as the thickness of the heat-conducting structure 200.

[0094] In some embodiments, the battery module includes a cold plate 2000 , the battery cells 1000 are disposed on the cold plate 2000 , and the cold plate 2000 has a groove 2100 , into which one end of the sheet structure 210 is inserted.

[0095] The cold plate 2000 is used to exchange heat with the battery cells 100. One end of the sheet structure 210 is inserted into the groove 2100 of the cold plate 2000, and the sheet structure 210 and the cold plate 2000 are fixedly connected via thermally conductive adhesive 300. The battery cells 100 transfer heat to the cold plate 2000 through the sheet structure 210 and thermally conductive adhesive 300, effectively improving the heat exchange efficiency between the battery cells 100 and the cold plate 2000. This fully utilizes the cooling effect of the cold plate 2000, resulting in better heat exchange and more efficient heat dissipation from the battery cells 100, which helps to extend the battery cell lifespan.

[0096] In some embodiments, the cold plate 2000 may not be provided with the groove 2100. The battery cell 1000 is disposed on the cold plate 2000. A thermally conductive adhesive 300 is provided at the connection between the cold plate 2000 and the sheet structure 210. The sheet structure 210 and the cold plate 2000 are fixedly connected by the thermally conductive adhesive 300. The battery cell 100 transfers heat to the cold plate 2000 through the sheet structure 210 and the thermally conductive adhesive 300. This effectively improves the heat exchange efficiency between the battery cell 100 and the cold plate 2000, fully utilizing the cooling effect of the cold plate 2000, resulting in a better heat exchange effect for the battery cell 100 and more efficient heat dissipation of the battery cell 100, which is conducive to increasing the service life of the battery cell.

[0097] Thermally conductive adhesive is a single-component, heat-conductive, room-temperature curing silicone adhesive sealant. It undergoes a condensation reaction with moisture in the air, releasing low-molecular-weight compounds that cross-link and cure, ultimately vulcanizing into a high-performance elastomer. Thermally conductive adhesives can be made from silicone, epoxy AB adhesives, acrylic, polyurethane, and other materials.

[0098] In other embodiments, referring to Figures 7 and 9, the heat-conducting structure 200 is a shell structure 220, the shell structure 220 has an accommodating space 225, the battery cell 100 has a pole 110 at the first end along the height direction, and the accommodating space 225 has an opening 226 at at least one end along the height direction. The battery cell 100 is at least partially accommodated in the accommodating space 225, and the first end of the battery cell 100 is exposed at the opening 226.

[0099] The housing space 225 of the casing structure 220 is used to accommodate the battery cells 100. The housing space 225 has an opening 226 at at least one end along the height direction, facilitating the placement of the battery cells 100 within the casing structure 220. Because the casing structure 220 has multiple surfaces in contact with the battery cells 100, heat from the center of the contact surface of the stacked battery cells 100 along a first direction can be rapidly transferred through the casing structure 220 to other locations on the battery cells 100, thereby rapidly reducing the temperature at the center of the contact surface of the battery cells 100.

[0100] It should be noted that there are two situations in which the accommodating space 225 has an opening 226 at at least one end along the height direction: First, as shown in FIG7 , the accommodating space 225 has an opening 226 at one end along the height direction, while the other end is closed, and the opening 226 is located at the end of the accommodating space 225 near the terminal of the battery cell 100. Second, as shown in FIG9 , the accommodating space 225 has an opening 226 at each end along the height direction.

[0101] In some embodiments, the casing structure 220 is sealed at locations other than the opening 226 , thereby ensuring heat conduction while also facilitating connection reliability between the casing structure 220 and the battery cell 100 .

[0102] In some other embodiments, referring to FIG. 8 , the casing structure 220 has a notch 227 on at least one side along the second direction W2 , wherein the second direction W2 , the first direction W1 , and the height direction are perpendicular to each other.

[0103] In some embodiments, the thickness L3 of the casing structure 220 is 0.02 mm to 0.5 mm. For example, 0.02 mm, 0.06 mm, 0.1 mm, 0.14 mm, 0.18 mm, 0.22 mm, 0.26 mm, 0.3 mm, 0.34 mm, 0.38 mm, 0.42 mm, 0.46 mm, 0.5 mm, etc. In this embodiment, the thickness of the casing structure 220 within this range can ensure the structural strength of the casing structure 220 while maintaining an appropriate spacing between two adjacent battery cells 100, making the battery module structure compact and saving battery module space.

[0104] The thickness L3 of the casing structure 220 refers to the maximum dimension of the casing structure 220 along its thickness direction. When measuring, a vernier caliper may be used to clamp the casing structure 220 for measurement.

[0105] In some embodiments, as shown in Figure 10 , the casing structure 220 includes, from the inside out, a first adhesive film layer 221, a thermally conductive film layer 222, a second adhesive film layer 223, and an insulating film layer 224. The first adhesive film layer 221 is bonded to the battery cells 100, while the thermally conductive film layer 222 and the insulating film layer 224 are bonded together via the second adhesive film layer. The first adhesive film layer 221 is bonded to the battery cells 100 and the thermally conductive film layer 222, securing the thermally conductive film layer 222 to the corresponding battery cells 100. The insulating film layer 224 provides insulation for the casing structure 220, while the second adhesive film layer is disposed between the thermally conductive film layer 222 and the insulating film layer 224, securing the insulating film layer 224 to the thermally conductive film layer 222. This arrangement ensures both the thermal conductivity and the insulating performance of the casing structure 220.

[0106] The material of the first adhesive film layer 221 and the second adhesive film layer 224 is an adhesive, for example, copper oxide phosphate, white latex, polyimide-based adhesive, phenolic resin adhesive, acrylaldehyde-based adhesive, polyurethane adhesive, epoxy resin adhesive, cyanoacrylate adhesive, anaerobic adhesive, inorganic adhesive, hot melt adhesive, etc.

[0107] The thermal conductive film layer 222 is made of a material with thermal conductivity, such as metal sheet, aluminum nitride, silicon carbide, graphite, etc.

[0108] The insulating film layer 224 is made of an insulating material that is non-conductive under an allowable voltage, such as polyvinyl chloride, polyethylene, polypropylene, polyester, natural rubber, artificial rubber, silicone rubber, insulating oil, insulating paint, insulating adhesive, etc.

[0109] In the description of the present disclosure, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present disclosure. In the present disclosure, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine different embodiments or examples described in the present disclosure and features of different embodiments or examples without mutual contradiction.

[0110] The foregoing description is merely a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present disclosure shall be included within the scope of protection of the present disclosure.

Claims

1. A battery module comprising: One or more battery cells, each comprising at least one heat-conducting structure and at least two battery cells stacked in a first direction; The heat-conducting structure is at least partially disposed between two adjacent battery cells along the first direction; The thermal conductivity of the heat-conducting structure along the first direction is smaller than the thermal conductivity in a direction perpendicular to the first direction.

2. The battery module according to claim 1, wherein: A ratio of a thermal conductivity coefficient of the heat-conducting structure along a direction perpendicular to the first direction to a thermal conductivity coefficient along the first direction is greater than or equal to 4.

3. The battery module according to claim 1 or 2, wherein: The heat-conducting structure is a sheet-shaped structure and is sandwiched between two adjacent battery cells.

4. The battery module according to claim 3, wherein: The sheet structure includes a heat insulating layer and at least two heat conducting layers. Each of the heat conducting layers is arranged on two opposite sides of the heat insulating layer along the first direction. The thermal conductivity of the heat conducting layer is greater than that of the heat insulating layer.

5. The battery module according to claim 4, wherein: The sheet structure further includes an insulating layer and an adhesive layer. The insulating layer is arranged on a side of the heat-conducting layer away from the heat-insulating layer. The adhesive layer is arranged on a side of the insulating layer away from the heat-conducting layer for bonding to the battery cell.

6. The battery module according to claim 4 or 5, wherein: The thickness of the heat-conducting layer is 0.02 mm to 1 mm.

7. The battery module according to any one of claims 4 to 6, wherein: The heat insulation layer has pores, so that the heat insulation layer is compressed under the squeezing action of two adjacent battery cells along the first direction.

8. The battery module according to any one of claims 4 to 7, wherein: The heat insulation layer is any one or more of foam, rubber, ceramic fiber, glass fiber, and aerogel.

9. The battery module according to any one of claims 4 to 8, wherein: The heat-conducting layer is any one or more of a metal sheet, aluminum nitride, and silicon carbide; and / or the thermal conductivity of the heat-conducting layer is ≥200 W / (m*K).

10. The battery module according to claim 3, wherein: The sheet structure is a single-layer structure. The thermal conductivity of the heat-conducting structure along a first direction is ≤100 W / (m*K). The thermal conductivity of the heat-conducting structure along a direction perpendicular to the first direction is ≥400 W / (m*K).

11. The battery module according to any one of claims 3 to 10, wherein: There are a plurality of battery cells, and the plurality of battery cells are arranged side by side along the second direction, wherein at least one of the sheet-like structures extends between two adjacent battery cells of another battery cell.

12. The battery module according to any one of claims 3 to 11, wherein: The thickness of the sheet structure along the first direction is 0.2 mm to 5 mm.

13. The battery module according to any one of claims 3 to 12, wherein: The battery module includes a cold plate, the battery cells are arranged on the cold plate, the cold plate has a groove, and one end of the sheet structure is inserted into the groove.

14. The battery module according to any one of claims 1 to 13, wherein: The heat-conducting structure is a shell structure, which has a accommodating space. The first end of the battery cell along the height direction has a pole, and at least one end of the accommodating space along the height direction has an opening. The battery cell is at least partially accommodated in the accommodating space, and the first end of the battery cell is exposed at the corresponding opening.

15. The battery module according to claim 14, wherein: The housing structure is a sealing structure at a portion other than the opening.

16. The battery module according to claim 14, wherein: The casing structure has a notch on at least one side along the second direction, wherein the second direction, the first direction, and the height direction are perpendicular to each other.

17. The battery module according to any one of claims 14 to 16, wherein: The thickness of the shell structure is 0.02mm to 0.5mm.

18. The battery module according to any one of claims 12 to 17, wherein: The casing structure includes, from inside to outside, a first adhesive film layer, a heat conductive layer, a second adhesive film layer, and an insulating film layer. The first adhesive film layer is bonded to the battery cell, and the heat conductive layer and the insulating layer are bonded via the second adhesive film layer.

19. A battery pack comprising the battery module according to any one of claims 1 to 18.

20. An electrical device comprising the battery module according to any one of claims 1 to 18 or the battery pack according to claim 19.

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