Battery module, battery pack and electric device

Abstract

The utility model is applicable to the technical field of batteries, and provides a battery module, a battery pack and a power utilization device, the power utilization 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 monomers stacked along a first direction. And the heat conduction structure is at least partially arranged between two adjacent battery monomers along the first direction. The heat conduction coefficient of the heat conduction structure in the first direction is smaller than the heat conduction coefficient in the direction perpendicular to the first direction. According to the application, the temperature of the central position of the battery monomer can be quickly reduced, the thermal influence of the battery monomer on the adjacent battery monomers stacked along the first direction is reduced, and the probability of thermal runaway is reduced, so that the risk of failure of the whole battery module caused by thermal diffusion between the battery monomers is reduced.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to a battery module, a battery pack and an electrical device. Background Art

[0002] 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 heat dissipation to dissipate heat from battery cells. However, this heat dissipation method causes the temperature of the battery cells far 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 adjacent active materials to reach the instability point and cause heat diffusion, which ultimately leads to the failure of the entire battery module. Summary of the invention

[0003] In view of this, the embodiments of the present application 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 failure of the entire battery module due to heat diffusion between the battery cells.

[0004] In a first aspect, an embodiment of the present application provides a battery module, comprising:

[0005] One or more battery cells, the battery cells comprising at least one thermally conductive structure and at least two battery cells stacked along a first direction;

[0006] The heat-conducting structure is at least partially disposed between two adjacent battery cells along the first direction;

[0007] Wherein, 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.

[0008] The battery module provided in the embodiment of the present application quickly transfers the heat at 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, thereby reducing the probability of thermal runaway; in addition, because the thermal conductivity of the heat-conducting structure along the first direction is smaller 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.

[0009] 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 of the heat-conducting structure along the first direction is greater than or equal to 4.

[0010] Such an arrangement enables the heat-conducting structure to quickly conduct heat 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.

[0011] In some embodiments, the heat conductive structure is a sheet-like structure and is sandwiched between two adjacent battery cells.

[0012] With such arrangement, the heat-conducting structure is simple in structure, easy to manufacture, and facilitates neat stacking of battery cells along the first direction.

[0013] In some embodiments, the sheet structure includes a heat insulating layer and at least two heat conducting layers, each of the heat conducting layers is disposed on opposite sides of the heat insulating layer along the first direction, and the thermal conductivity of the heat conducting layer is greater than the thermal conductivity of the heat insulating layer.

[0014] With such arrangement, the heat-conducting layer can quickly transfer the temperature of the center of the battery cell to the periphery of the center of the battery cell. Since the heat-insulating layer is located in the middle of the heat-conducting layer, the heat impact of the battery cell on the adjacent battery cells stacked along the first direction is reduced.

[0015] In some embodiments, the sheet structure further includes an insulating layer and an adhesive layer, wherein the insulating layer is disposed on a side of the heat-conducting layer away from the heat-insulating layer, and the adhesive layer is disposed on a side of the insulating layer away from the heat-conducting layer, for bonding with the battery cell. The insulating layer can give the heat-conducting structure a good electrical insulation effect. The adhesive layer is used to bond the heat-conducting structure to the battery cell, so that the fit between the two is more reliable and the heat transfer effect is better.

[0016] 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, which can not only make the battery module structure compact and save battery module space, but also ensure heat dissipation effect.

[0017] In some embodiments, the heat insulating layer has pores so that the heat insulating layer is compressed under the extrusion of two adjacent battery cells along the first direction. With this arrangement, when the battery module is vibrated or expanded, two adjacent battery cells squeeze the heat conductive structure along the first direction. Since the heat insulating layer has pores, it is compressed under the extrusion force, which reduces the extrusion force between adjacent battery cells, thereby enhancing the safety performance of the battery module.

[0018] In some embodiments, the heat insulating layer is any one or more of foam, rubber, ceramic fiber, glass fiber, and aerogel, so that the heat insulating layer has good heat insulating effect and compression performance.

[0019] In some embodiments, the number of the battery cells is multiple, and the multiple battery cells are arranged side by side along the second direction, wherein at least one of the sheet structures extends between two adjacent battery cells of another battery cell, so that at least two adjacent battery cells along the second direction share the sheet structure. In this way, the heat at the center of the contact surface of the battery cell in contact with the sheet structure is quickly transferred to the battery cell sharing the sheet structure through the sheet structure. By sharing the heat together with the adjacent battery cells along the second direction, the cooling can be further accelerated.

[0020] 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, which can make the battery module structure compact, save battery module space, and ensure heat dissipation effect.

[0021] In some embodiments, the battery module includes a cold plate, the battery cell is disposed on the cold plate, the cold plate has a groove, and one end of the sheet structure is inserted into the groove.

[0022] 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.

[0023] In some embodiments, the heat-conducting structure is a shell structure, the shell structure has a accommodating space, the first end of the battery cell along the height direction has a pole, the accommodating space has an opening at at least one end along the height direction, the battery cell is at least partially accommodated in the accommodating space, and the first end of the battery cell is exposed at the opening. The accommodating space of the shell structure is used to accommodate the battery cell, and the accommodating space has an opening at at least one end along the height direction, so that the battery cell can be accommodated in the shell structure. Since the shell structure has multiple surfaces in contact with the battery cell, the heat at the center position of the contact surface of the battery cell stacked along the first direction can be quickly transferred to other positions of the battery cell through the shell structure, thereby quickly reducing the temperature at the center position of the contact surface of the battery cell.

[0024] In some embodiments, the casing structure is a sealed structure at a portion other than the opening, so that the heat conduction effect is ensured while also ensuring the reliability of the connection between the casing structure and the battery cell.

[0025] 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.

[0026] 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 and maintain a suitable spacing between two adjacent battery cells, making the battery module structure compact and saving battery module space.

[0027] In some embodiments, the shell structure includes a first adhesive film layer, a heat-conducting film layer, a second adhesive film layer, and an insulating film layer from the inside to the outside, wherein the first adhesive film layer is bonded to the battery cell, and the heat-conducting film layer and the insulating film layer are bonded to each other through the second adhesive film layer. The first adhesive film layer is bonded to the battery cell and the heat-conducting layer, so that the heat-conducting film layer is bonded and fixed to the corresponding battery cell; the insulating film layer is used to make the shell structure have an insulating effect, and the second adhesive film layer is arranged between the heat-conducting film layer and the insulating film layer, so that the insulating film layer is bonded and fixed to the heat-conducting film layer. With such an arrangement, the insulation performance of the shell structure is taken into account while ensuring the thermal conductivity of the shell structure.

[0028] In a second aspect, an embodiment of the present application provides a battery pack, comprising the battery module described in any embodiment of the present application.

[0029] The battery pack provided in the embodiment of the present application, 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 failure of the entire battery module due to heat diffusion between the battery cells.

[0030] The electric device provided in the embodiment of the present application, by using the battery module or battery pack 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 failure of the entire battery module caused by heat diffusion between the battery cells. This makes the electric device have lower cost and higher reliability.

[0031] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, 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 application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A partial structural schematic diagram of a battery module provided in some embodiments of the present application;

[0033] Figure 2 A schematic diagram of a sheet-like heat-conducting structure and a battery cell adjacent thereto provided in some embodiments of the present application;

[0034] Figure 3 A schematic diagram of the composition structure of a sheet-like heat-conducting structure provided in some embodiments of the present application;

[0035] Figure 4 for Figure 1 A top view of

[0036] Figure 5 For the cold plate with groove structure Figure 4 Section view along AA;

[0037] Figure 6 For the cold plate with groove structure Figure 4 A partial enlarged view of point B of the cross-sectional view along AA;

[0038] Figure 7 For the cold plate without groove structure Figure 4 Section view along AA;

[0039] Figure 8 For the cold plate without groove structure Figure 4 A partial enlarged view of point C of the cross-sectional view along AA;

[0040] Fig. 9 Schematic diagram of a casing structure and a battery cell provided in some embodiments of the present application, with one side opening in the height direction and other parts being sealed structures;

[0041] Fig.10 A schematic diagram of a casing structure and a battery cell having a notch on at least one side along the second direction provided in some embodiments of the present application;

[0042] Fig.11 Schematic diagram of a casing structure and a battery cell with openings on both sides in the height direction provided in some embodiments of the present application;

[0043] Fig.12 A schematic diagram of the composition structure of the shell structure provided in some embodiments of the present application.

[0044] Description of reference numerals:

[0045] 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 heat-conducting layer; L2, thickness of heat-conducting structure; L3, thickness of casing structure; W1, first direction; W2, second direction. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with 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.

[0047] The various specific technical features described in the specific embodiments can be combined in any suitable manner without contradiction, for example, different embodiments and technical solutions can be formed by combining different specific technical features. In order to avoid unnecessary repetition, various possible combinations of the specific technical features in the present invention will not be described separately.

[0048] In the following description, the terms "first\second\..." are only used to distinguish different objects, and do not mean that the objects have the same or related points. It should be understood that the directions "above", "below", "outside" and "inside" are all directions in normal use, and the directions "left" and "right" refer to the left and right directions shown in the specific corresponding schematic diagrams, which may be the left and right directions in normal use or not.

[0049] It should be noted that the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element. "Multiple" means greater than or equal to two.

[0050] At present, new energy batteries are increasingly used in life and industry. New energy batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0051] In the related art, the battery module adopts the bottom heat dissipation method to dissipate the heat of the battery cells. However, this heat dissipation method makes the temperature of the battery cells farther away from the heat dissipation interface higher, especially the temperature of the central area of ​​the contact surface of two adjacent battery cells is higher. The extreme temperature of the central area may cause the internal active materials to reach the instability point and cause heat diffusion, eventually leading to the failure of the entire battery module.

[0052] In view of the above problems, an embodiment of the present application provides a battery module, including one or more battery cells, wherein the battery cell includes 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. Among them, 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, thereby 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, and the risk of heat diffusion between the battery cells causing failure of the entire battery module is reduced.

[0053] An embodiment of the present application provides a battery pack, which includes the above-mentioned battery module.

[0054] The embodiment of the present application also provides an electric device, including the above-mentioned battery module or battery pack. The battery module or battery pack can provide electrical energy for the electric device. The electric device can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0055] In the following embodiments, for the convenience of description, an electric vehicle according to an embodiment of the present application is taken as an example for description.

[0056] The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended range vehicle. A battery is provided inside the vehicle. The battery may be provided at the bottom, head or tail of the vehicle. The battery may be used to power the vehicle. For example, the battery may be used as an operating power source for the vehicle. The vehicle may also include a controller and a motor. The controller is used to control the battery to power the motor, for example, for starting, navigating and operating power requirements of the vehicle during driving.

[0057] In some embodiments of the present application, the battery can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0058] The present application embodiment provides a battery module, see Figure 1 The battery module includes one or more battery cells 1000. The battery cell 1000 includes at least one heat-conducting structure 200 and at least two battery cells 100 stacked along a first direction W1. At least part of the heat-conducting structure 200 is disposed between two adjacent battery cells 100 along the first direction W1; wherein the thermal conductivity of the heat-conducting structure 200 along the first direction W1 is less than the thermal conductivity in a direction perpendicular to the first direction W1.

[0059] Figure 1 In the figure, the structure in the dotted box indicates a battery cell 1000. It can be understood that in the embodiment of the present application, the number of battery cells 1000 can be one, two, or more than two.

[0060] The battery cell 100 refers to the basic device and basic unit that directly converts chemical energy into electrical energy, and is the basic element of the battery. Its components include electrolyte, positive and negative electrodes, and separators. The battery cell 100 is also the smallest unit that constitutes the power battery module.

[0061] Exemplarily, the battery cell 100 includes a housing and an electrode assembly, wherein the electrode assembly is disposed in the housing. The housing is an appearance structural component of the battery cell 100.

[0062] 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 active materials constitutes the main body of the electrode assembly, and the main body is connected to the pole ears. The positive pole ear and the negative pole ear 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 pole ears connect the pole column 110 to form a current loop.

[0063] The shell is a component that isolates the internal environment of the battery cell 100 from the external environment. The shell can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the shell is not easily deformed when squeezed or collided, so that the battery cell 100 can have a higher structural strength and the safety performance can also be improved.

[0064] 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 .

[0065] Thermal conductivity, also known as thermal conductivity or thermal conductivity, is an important physical quantity that measures the thermal conductivity of a material. It is defined as the amount of heat transferred through an area of ​​1 square meter per unit time under stable heat transfer conditions when the material thickness is 1 meter and the temperature difference between the two surfaces is 1 degree (K or ℃). The unit of thermal conductivity is usually Watt per meter per Kelvin (W / (m·K)), and is sometimes expressed in Joule per square meter Kelvin (J / (m·K)) in the International System of Units. The size of the thermal conductivity has an important influence on the thermal insulation or heat dissipation performance of the material. For example, materials with low thermal conductivity perform well in thermal insulation, while materials with high thermal conductivity are suitable for occasions that require rapid heat transfer.

[0066] The battery module of the embodiment of the present application quickly transfers the heat at the center position of the contact surface of the battery cell 100 in contact with the heat conductive structure 200 to other positions of the contact surface of the battery cell 100 through the heat conductive structure 200, thereby reducing the temperature at the center position of the battery cell 100, thereby reducing the probability of thermal runaway; in addition, because the thermal conductivity of the heat conductive structure 200 along the first direction W1 is smaller than the thermal conductivity in the direction perpendicular to the first direction W1, the thermal influence 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.

[0067] In the embodiment of the present application, taking the battery cell 100 as a rectangular battery cell 100 as an example, the large surfaces of the same group of battery cells 100 are stacked together, and the small surfaces of the two groups of battery cells 100 are arranged together. That is, 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.

[0068] 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 quickly along the direction perpendicular to the first direction W1, and also reduces the thermal impact of the battery cell 100 on the adjacent battery cells 100 stacked along the first direction W1.

[0069] The specific shape of the heat conducting structure 200 is not limited.

[0070] For example, in some embodiments, see Figure 2 The heat-conducting structure 200 is a sheet-shaped structure 210 and is sandwiched between two adjacent battery cells 100. In this way, the heat-conducting structure 200 has a simple structure, is easy to manufacture, and facilitates the neat stacking of the battery cells 100 along the first direction.

[0071] The sheet structure 210 may be a single-layer structure, a double-layer composite structure, a three-layer composite structure, or a composite structure having more layers.

[0072] In the embodiment where the sheet structure 210 is a single-layer structure, the sheet structure 210 may be a material having anisotropic thermal conductivity, such as a graphite sheet, etc. That is, the thermal conductivity along the first direction W1 is achieved by the microscopic physical properties of the material itself, which is less than the thermal conductivity in the direction perpendicular to the first direction W1. Exemplarily, in the embodiment 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 the direction perpendicular to the first direction is ≥400 W / (m*K).

[0073] For example, in some embodiments, see Figure 3 , the sheet structure 210 includes a heat insulating layer 212 and at least two heat conducting layers 211, each heat conducting layer 211 is arranged on opposite sides of the heat insulating layer 212 along the first direction W1, and the thermal conductivity of the heat conducting layer 211 is greater than the thermal conductivity of the heat insulating layer 212. That is to say, in this embodiment, the sheet structure 210 is at least a three-layer composite structure. In this embodiment, it can be made of materials such as metal sheets, aluminum nitride, or silicon carbide. The difference in thermal conductivity of the sheet structure 210 in the first direction and perpendicular to the first direction can be achieved by the heat insulating layer 212. The heat insulating effect of the heat insulating layer 212 makes the thermal conductivity of the heat conducting structure 200 along the first direction smaller than the thermal conductivity perpendicular to the first direction.

[0074] With this configuration, the heat conductive layer 211 can quickly transfer the temperature of the center of the battery cell 100 to the periphery 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 thermal impact of the battery cell 100 on the adjacent battery cells 100 stacked along the first direction W1 is reduced.

[0075] The material of the heat insulation layer 212 is a heat insulation material, also known as a thermal insulation material, which can block the transfer of heat flow, for example, glass fiber, asbestos, rock wool, foam, silicate, vacuum board, rubber, ceramic fiber, aerogel, etc.

[0076] The material of the heat-conducting layer 211 can be a material with heat-conducting properties, and the thermal conductivity of the heat-conducting layer 211 along any direction is the same, such as metal sheet, aluminum nitride, silicon carbide, etc.

[0077] Exemplarily, the thermal conductivity of the heat-conducting layer 211 is ≥ 200 W / (m*K).

[0078] 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 a side of the heat conductive layer 211 away from the heat insulating layer 212, and the adhesive layer 214 is disposed on a side of the insulating layer 213 away from the heat conductive layer 211, for bonding with the battery cell 100. That is, in this embodiment, the sheet structure 210 is at least a five-layer composite structure.

[0079] The insulating layer 213 can provide good electrical insulation effect for the heat-conducting structure 200. The adhesive layer 214 is used to bond the heat-conducting structure 200 to the battery cell 100, so that the bonding between the two is more reliable and the heat transfer effect is better.

[0080] The insulating layer 213 is made of insulating material, which is a 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 paint, insulating adhesive, etc.

[0081] The material of the bonding layer 214 is adhesive, for example, it can be copper phosphate monoxide, 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.

[0082] 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 a suitable spacing between two adjacent battery cells 100, which can make the battery module structure compact, save battery module space, and ensure heat dissipation effect.

[0083] 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 the distance is regarded as the thickness of the heat-conducting layer 211 .

[0084] In some embodiments, the heat insulating layer 212 has pores so that the heat insulating layer 212 is compressed under the extrusion of two adjacent battery cells 100 along the first direction W1. With such a configuration, when the battery module is vibrated or expanded, the two adjacent battery cells 100 squeeze the heat conductive structure 200 along the first direction W1. Since the heat insulating layer has pores, it is compressed under the extrusion force, which reduces the extrusion force between the adjacent battery cells 100, thereby enhancing the safety performance of the battery module.

[0085] In some embodiments, the heat insulating layer 212 may be any one or more of foam, rubber, ceramic fiber, glass fiber, and aerogel, so that the heat insulating layer 212 has good heat insulating effect and compression performance.

[0086] 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 facilitating heat conduction.

[0087] The number of the battery unit 1000 may be one or more.

[0088] 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. Among them, 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. In this way, the heat at the center of the contact surface of the battery cell 100 in contact with the sheet structure 210 is quickly transferred to the battery cell 100 sharing the sheet structure 210 through the sheet structure 210. By sharing the heat together with the adjacent battery cells along the second direction, the cooling can be further accelerated.

[0089] 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. In this way, a suitable spacing can be maintained between two adjacent battery cells 100, which can make the battery module structure compact, save battery module space, and ensure heat dissipation effect.

[0090] 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 is regarded as the thickness of the heat-conducting structure 200 .

[0091] In some embodiments, the battery module includes a cold plate 2000 , the battery cell 1000 is disposed on the cold plate 2000 , the cold plate 2000 has a groove 2100 , and one end of the sheet structure 210 is inserted into the groove 2100 .

[0092] The cold plate 2000 is used to exchange heat with the battery cell 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 by the thermal conductive adhesive 300. The battery cell 100 transfers heat to the cold plate 2000 through the sheet structure 210 and the thermal conductive adhesive 300, which effectively improves the heat exchange efficiency between the battery cell 100 and the cold plate 2000, gives full play to the cooling effect of the cold plate 2000, makes the heat exchange effect of the battery cell 100 better, and the heat dissipation of the battery cell 100 is more efficient, which is conducive to improving the service life of the battery cell.

[0093] In some embodiments, the cold plate 2000 may not be provided with the groove 2100. The battery unit 1000 is arranged on the cold plate 2000, and a thermal conductive adhesive 300 is provided at the connection between the cold plate 2000 and the sheet structure 210, and the sheet structure 210 and the cold plate 2000 are fixedly connected by the thermal conductive adhesive 300. The battery cell 100 transfers heat to the cold plate 2000 through the sheet structure 210 and the thermal conductive adhesive 300. The heat exchange efficiency between the battery cell 100 and the cold plate 2000 is effectively improved, and the cooling effect of the cold plate 2000 is fully utilized, so that the heat exchange effect of the battery cell 100 is better, and the heat dissipation of the battery cell 100 is more efficient, which is conducive to improving the service life of the battery cell.

[0094] 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 to release low-molecular substances, causing cross-linking and curing, and vulcanizing into a high-performance elastomer. The material of thermally conductive adhesive can be silicone thermally conductive adhesive, epoxy resin AB adhesive, acrylic thermally conductive adhesive, polyurethane thermally conductive adhesive, etc.

[0095] In some other embodiments, see Figure 7 and Fig. 9 The heat-conducting structure 200 is a shell structure 220, which has a housing space 225. The first end of the battery cell 100 along the height direction has a pole 110, and at least one end of the housing space 225 along the height direction has an opening 226. The battery cell 100 is at least partially accommodated in the housing space 225, and the first end of the battery cell 100 is exposed at the opening 226.

[0096] The accommodating space 225 of the casing structure 220 is used to accommodate the battery cell 100, and at least one end of the accommodating space 225 along the height direction has an opening 226, so that the battery cell 100 can be accommodated in the casing structure 220. Since the casing structure 220 has multiple surfaces in contact with the battery cell 100, the heat at the center of the contact surface of the battery cell 100 stacked along the first direction can be quickly transferred to other positions of the battery cell 100 through the casing structure 220, thereby quickly reducing the temperature at the center of the contact surface of the battery cell 100.

[0097] It should be noted that there are two situations in which at least one end of the accommodating space 225 along the height direction has an opening 226: the first situation, see Figure 7 , the accommodating space 225 has an opening 226 at one end along the height direction and is closed at the other end, and the opening 226 is located at the end of the accommodating space 225 close to the pole of the battery cell 100. The second type, please refer to Fig. 9 The accommodating space 225 has openings 226 at both ends along the height direction.

[0098] In some embodiments, the casing structure 220 is a sealed structure at a portion other than the opening 226. In this way, while ensuring the heat conduction effect, it is also beneficial to ensure the connection reliability between the casing structure 220 and the battery cell 100.

[0099] In some other embodiments, see Figure 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.

[0100] 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 a suitable spacing between two adjacent battery cells 100, so that the battery module structure is compact and the battery module space is saved.

[0101] 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.

[0102] In some embodiments, see Fig.10The shell structure 220 includes a first adhesive film layer 221, a heat-conducting film layer 222, a second adhesive film layer 223, and an insulating film layer 224 from the inside to the outside. The first adhesive film layer 221 is bonded to the battery cell 100, and the heat-conducting film layer 222 and the insulating film layer 224 are bonded through the second adhesive film layer 223. The first adhesive film layer 221 is bonded to the battery cell 100 and the heat-conducting film layer 222, so that the heat-conducting film layer 222 is bonded and fixed to the corresponding battery cell 100; the insulating film layer 224 is used to make the shell structure 220 have an insulating effect, and the second adhesive film layer 223 is arranged between the heat-conducting film layer 222 and the insulating film layer 224, so that the insulating film layer 224 is bonded and fixed to the heat-conducting film layer 222. In this way, the thermal conductivity of the shell structure 220 is ensured while taking into account the insulation performance of the shell structure 220.

[0103] The material of the first adhesive film layer 221 and the second adhesive film layer 224 is an adhesive, for example, copper phosphate monoxide, 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.

[0104] The material of the thermal conductive film layer 222 is a material with thermal conductivity, such as metal sheet, aluminum nitride, silicon carbide, graphite, etc.

[0105] The insulating film layer 224 is made of insulating material, which is a material that does not conduct electricity under the allowable voltage, such as polyvinyl chloride, polyethylene, polypropylene, polyester, natural rubber, artificial rubber, silicone rubber, insulating oil, insulating paint, insulating adhesive, etc.

[0106] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 application. In the present application, the schematic representation of the above terms is not necessarily for 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 application and the features of different embodiments or examples without contradiction.

[0107] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery module, characterized in that: include: One or more battery cells, the battery cells comprising at least one thermally conductive structure and at least two battery cells stacked along a first direction; The heat-conducting structure is at least partially disposed between two adjacent battery cells along the first direction; Wherein, 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, characterized in that: 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.

3. The battery module according to claim 1, characterized in that: 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, characterized in that: 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, and the thermal conductivity of the heat conducting layer is greater than the thermal conductivity of the heat insulating layer.

5. The battery module according to claim 4, characterized in that: 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, and the adhesive layer is arranged on a side of the insulating layer away from the heat-conducting layer for bonding with the battery cell.

6. The battery module according to claim 4, characterized in that: The thickness of the heat-conducting layer is 0.02 mm to 1 mm.

7. The battery module according to claim 4, characterized in that: The heat insulation layer has pores so that the heat insulation layer is compressed under the extrusion of two adjacent battery cells along the first direction.

8. The battery module according to claim 4, characterized in that: The heat insulation layer is any one or any combination of foam, rubber, ceramic fiber, glass fiber, and aerogel.

9. The battery module according to any one of claims 3 to 8, characterized in that: 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.

10. The battery module according to any one of claims 3 to 8, characterized in that: The thickness of the sheet structure along the first direction is 0.2 mm to 5 mm.

11. The battery module according to any one of claims 3 to 8, characterized in that: The battery module comprises a cold plate, the battery unit is arranged on the cold plate, the cold plate has a groove, and one end of the sheet structure is inserted into the groove.

12. The battery module according to claim 1, characterized in that: The heat-conducting structure is a shell structure having a housing space, the first end of the battery cell along the height direction has a pole, at least one end of the housing space along the height direction has an opening, the battery cell is at least partially accommodated in the housing space, and the first end of the battery cell is exposed at the corresponding opening.

13. The battery module according to claim 12, characterized in that: The casing structure is a sealing structure at a position other than the opening.

14. The battery module according to claim 12, characterized in that: 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.

15. The battery module according to claim 12, characterized in that: The thickness of the shell structure is 0.02 mm to 0.5 mm.

16. The battery module according to any one of claims 12 to 15, characterized in that: The casing structure includes, from inside to outside, a first adhesive film layer, a heat conductive film 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 film layer and the insulating film layer are bonded to each other through the second adhesive film layer.

17. A battery pack, characterized in that: A battery module comprising any one of claims 1-16.

18. An electrical device, characterized in that: Comprising the battery module according to any one of claims 1 to 16 or the battery pack according to claim 17.

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