Battery device and electric appliance

Abstract

The application relates to the technical field of batteries, in particular to a battery device and an electric equipment. The battery device comprises a box body and a plurality of battery monomers. An accommodating cavity is formed in the box body. The plurality of battery monomers are arranged in the accommodating cavity. The plurality of battery monomers are arranged along a first direction. At least part of the battery monomers are arranged along one side of a second direction and are spaced apart from the inner wall surface of the accommodating cavity to form a moving space. The first direction intersects the second direction. At least part of the battery monomers are configured to move along the second direction towards the moving space under the condition of thermal runaway. According to the battery device, when the battery monomers have thermal runaway, the battery monomers can move along the second direction, thereby being arranged in dislocation with adjacent battery monomers along the second direction. The contact area of the battery monomers having thermal runaway and the adjacent battery monomers along the second direction is reduced, and the temperature rise of the adjacent battery monomers is reduced.

Description

Technical Field

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

[0002] Lithium-ion batteries are now widely used in the electric vehicle industry. With the increasing prevalence of electric vehicles, the safety of battery systems is receiving growing attention. The battery cells in an electric vehicle are composed of individual cells connected in series or parallel. Due to the temperature characteristics of individual cells, they cannot function properly in high-temperature environments, severely impacting the performance of the battery system.

[0003] When a battery cell experiences thermal runaway and its temperature rises, it can cause the temperature of other normally functioning battery cells adjacent to it to rise as well, leading to the spread of thermal runaway and affecting the performance of the entire battery cell assembly. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the purpose of this application is to provide a battery device and electrical equipment that can effectively reduce the problem of temperature rise of adjacent battery cells when thermal runaway occurs in a single battery cell.

[0005] The first aspect of this application discloses a battery device, comprising:

[0006] The box has an internal cavity for receiving contents.

[0007] Multiple battery cells are disposed within a receiving cavity, and the multiple battery cells are arranged along a first direction. At least a portion of the battery cells are spaced apart from the inner wall of the receiving cavity along one side of a second direction to form an active space. The first direction intersects the second direction, and at least a portion of the battery cells are configured to move along the second direction toward the active space under the condition of thermal runaway.

[0008] According to the battery device of this application, when a battery cell experiences thermal runaway, the battery cell can move along a second direction into the active space, thereby offsetting itself from adjacent battery cells along the second direction. This reduces the contact area between the thermally runaway battery cell and adjacent battery cells along the second direction, reduces the temperature rise of adjacent battery cells, and helps dissipate heat from the thermally runaway battery cell.

[0009] In some embodiments of this application, at least a portion of the battery cells are bonded to the inner wall of the receiving cavity or the support member inside the box by an adhesive on the same side surface along the second direction, wherein the heat distortion temperature of the adhesive is less than or equal to the thermal runaway temperature of the battery cell.

[0010] By setting the heat distortion temperature of the adhesive to be less than or equal to the thermal runaway temperature of the battery cell, when the battery cell is about to experience thermal runaway or has already experienced thermal runaway, the temperature of the battery cell rises and it expands. At the same time, the temperature rise of the battery cell causes the adhesive connected to it to undergo thermal deformation and fail. After the adhesive fails, it can no longer provide adhesive force to the battery cell. After the expanded battery cell loses the adhesive effect, it can move in the direction away from the adhesive along the second direction, thereby misaligning with the adjacent battery cells along the second direction. This reduces the contact area between the battery cell about to experience thermal runaway or has already experienced thermal runaway and the adjacent battery cells along the second direction, reduces the temperature rise of the adjacent battery cells, and also helps to dissipate heat from the battery cell about to experience thermal runaway or has already experienced thermal runaway.

[0011] In some embodiments of this application, the heat distortion temperature of the adhesive is greater than or equal to 80°C and less than or equal to 250°C.

[0012] The normal operating temperature of a battery cell is less than 80°C. By setting the heat distortion temperature of the adhesive to greater than or equal to 80°C, the adhesive force of the adhesive can be improved when the battery cell is operating normally, reducing the movement of the battery cell. However, the temperature of a battery cell when it experiences thermal runaway can generally reach above 250°C. By setting the heat distortion temperature of the adhesive to less than or equal to 250°C, the adhesive can be thermally deformed and fail when the battery cell is about to experience thermal runaway or when thermal runaway has already occurred. This prevents the adhesive from providing adhesive force to the battery cell, allowing the battery cell to move in the second direction.

[0013] In some embodiments of this application, the adhesive includes at least one of thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive, and polyurethane adhesive.

[0014] The heat distortion temperature of any one of the thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive and polyurethane adhesive can be set to be less than or equal to the thermal runaway temperature of the battery cell. Therefore, the adhesive can be set to at least one of the thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive and polyurethane adhesive.

[0015] In some embodiments of this application, the adhesive includes a thermally expandable adhesive, which is configured such that the temperature at which expansion occurs is less than or equal to the thermal runaway temperature of the battery cell.

[0016] By setting the adhesive as a thermally expandable adhesive, and configuring the thermally expandable adhesive to expand at a temperature less than or equal to the thermal runaway temperature of the battery cell, when the battery cell is about to or has already experienced thermal runaway, the thermally expandable adhesive connected to it can not only undergo thermal deformation and fail, resulting in the loss of adhesion to the battery cell, but also expand when heated. This expands the thermally expandable adhesive, thereby pushing the battery cell that is about to or has already experienced thermal runaway in a direction away from the adhesive, thereby reducing the contact area between the battery cell that is about to or has already experienced thermal runaway and the adjacent battery cells in the second direction.

[0017] In some embodiments of this application, the thermally expandable adhesive is configured to expand thermally when the temperature reaches 200°C, and the expanded volume is 3 to 5 times the volume before expansion.

[0018] By setting the thermal expansion adhesive to expand when the temperature reaches 200℃, and the expanded volume being 3 to 5 times the original volume, the thermal expansion adhesive can cause thermal failure and expansion deformation when the battery cell is about to experience thermal runaway. This allows the expanded thermal expansion adhesive to push the battery cell that is about to experience thermal runaway to move in the direction away from the adhesive.

[0019] In some embodiments of this application, the battery device further includes a heat exchange plate forming a support member, and at least a portion of the battery cells are connected to the heat exchange plate by an adhesive on the same side surface along the second direction.

[0020] The heat exchange plate can exchange heat with the battery cells, thereby regulating the temperature of the battery cells. At the same time, the surface of the heat exchange plate is easy to use to bond and fix the battery cells with adhesive.

[0021] In some embodiments of this application, the battery cell includes a first surface with the largest area, and a first direction is perpendicular to the first surface.

[0022] By arranging the first surface perpendicular to the first direction and arranging multiple battery cells along the first direction, the size of the battery cells along the first direction can be reduced, thereby increasing the number of battery cells arranged in the battery cell assembly along the first direction.

[0023] In some embodiments of this application, at least a portion of the battery cells include a support portion and a deformable portion arranged sequentially along the second direction, wherein the deformable portion has a greater deformable capacity along the first direction than the support portion has a greater deformable capacity along the first direction, and the side where the support portion is located has a space for movement.

[0024] When a battery cell experiences thermal runaway, the active material within the cell reacts and decreases. When the pressure inside the cell reaches a certain level, the pressure relief mechanism opens and releases the pressure, causing the internal pressure of the thermally runaway cell to decrease. Simultaneously, the temperature of the normally functioning battery cell adjacent to the thermally runaway cell rises. Since the battery cell includes a support portion and a deformable portion arranged sequentially along the second direction, and the deformable portion's deformation capacity along the first direction is greater than that of the support portion, and the support portion has a space for movement, the deformable portion of the normally functioning battery cell, after being heated, can expand and deform towards the direction of the thermally runaway cell, compressing the thermally runaway cell and causing it to move along the second direction away from the adhesive.

[0025] In some embodiments of this application, the deformable portion has a recessed portion on the surface along the first direction, and the recessed portion extends along the third direction, with the first direction, the second direction, and the third direction being perpendicular to each other.

[0026] When a battery cell experiences thermal runaway, the surface of the deformable portion along the first direction has a recessed portion, and the recessed portion extends along the third direction. The wall thickness of the battery cell at the corresponding position of the recessed portion is less than the wall thickness of the battery cells on both sides of the recessed portion along the second direction. Therefore, the battery cell in its normal state after being heated can expand and deform in the direction of the battery cell that has experienced thermal runaway, and cause the portion on both sides of the recessed portion along the second direction to bend and deform around the third direction, thereby squeezing the battery cell that has experienced thermal runaway, and causing the battery cell that has experienced thermal runaway to move along the second direction in the direction away from the adhesive.

[0027] In some embodiments of this application, the battery cell includes two first surfaces disposed opposite to each other along a first direction, and the battery cell also includes two second surfaces disposed opposite to each other along a third direction. At least one first surface is provided with a recess, and the recess penetrates through the second surfaces on both sides along the third direction.

[0028] By extending the recessed portion through the second surface on both sides in a third direction, the bending deformation capability of the first surface around the third direction can be improved, thereby facilitating the movement of the battery cell in its normal state after thermal expansion along the second direction to push the thermally runaway battery cell.

[0029] In some embodiments of this application, a plurality of recesses are provided on the side of the first surface near the adhesive along the second direction, and the plurality of recesses are spaced apart and arranged in parallel along the second direction.

[0030] By arranging multiple recesses in parallel along the second direction, the bending deformation capability of the first surface around the third direction can be improved, thereby facilitating the movement of the thermally runaway battery cell along the second direction by the battery cell in its normal state after thermal expansion.

[0031] A second aspect of this application also proposes an electrical device, which includes the battery device of any of the above.

[0032] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0033] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0034] Figure 1 This is a structural schematic diagram of a vehicle provided in one embodiment of this application;

[0035] Figure 2 This is a schematic diagram of the structure of a battery device provided in one embodiment of this application;

[0036] Figure 3 This is a schematic diagram of the structure of a battery cell assembly provided in one embodiment of this application;

[0037] Figure 4 This is an exploded structural diagram of a battery cell provided in one embodiment of this application;

[0038] Figure 5 This is a schematic diagram of the connection structure between the battery cell assembly and the heat exchange plate provided in one embodiment of this application;

[0039] Figure 6 yes Figure 5 A schematic diagram of the connection structure between a single battery cell and a heat exchange plate when the cell is in a state of thermal runaway.

[0040] Figure 7 This is a schematic diagram of the connection structure between a battery cell and a heat exchange plate provided in another embodiment of this application;

[0041] Figure 8 yes Figure 7 A schematic diagram of the structure of a single battery cell in the diagram;

[0042] Figure 9 yes Figure 7 A schematic diagram of the connection structure between a single battery cell and a heat exchange plate when the cell is in a state of thermal runaway.

[0043] Figure 10 This is a schematic diagram of the structure of a battery cell assembly provided in another embodiment of this application;

[0044] Figure 11 yes Figure 10 A schematic diagram of the connection structure between the battery cell and the frame when the battery cell is in a state of thermal runaway.

[0045] Figure 12 This is a schematic diagram of the connection structure between the battery cell and the frame provided in another embodiment of this application;

[0046] Figure 13 yes Figure 12 A schematic diagram of the connection structure between the battery cell and the frame when the battery cell is in a state of thermal runaway.

[0047] The reference numerals in the detailed embodiments are as follows:

[0048] 1. Vehicles;

[0049] 10. Battery assembly; 11. Controller; 12. Motor;

[0050] 20. Battery cell assembly; 21. Battery cell; 211. End cap; 212. Housing; 2121. First surface; 21211. Recess; 2122. Second surface; 213. Electrode assembly; 214. Electrode terminal; 215. Pressure relief mechanism; 216. Support; 217. Deformable part; 22. Frame; 221. End plate; 222. Base plate;

[0051] 30. Box; 301. First box; 302. Second box;

[0052] 40. Adhesive; 41. Part One; 42. Part Two;

[0053] 50. Heat exchange plate;

[0054] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0055] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0056] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application shall have the ordinary meaning as understood by those skilled in the art to which the embodiments of this application pertain.

[0057] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and other terms indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0058] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0059] In the description of the embodiments of this application, unless otherwise explicitly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0060] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0061] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. Lithium-ion batteries, due to their high energy density, high average open-circuit voltage, and long cycle life, are widely used in mobile and portable electronic devices.

[0062] Lithium-ion batteries are now widely used in the electric vehicle industry. With the increasing prevalence of electric vehicles, the safety of battery systems is receiving growing attention. The battery cells in an electric vehicle are composed of individual cells connected in series or parallel. Due to the temperature characteristics of individual cells, they cannot function properly in high-temperature environments, severely impacting the performance of the battery system.

[0063] When a battery cell experiences thermal runaway and its temperature rises, it causes the temperature of adjacent, normally functioning battery cells to rise as well, leading to the spread of thermal runaway and affecting the performance of the entire battery cell assembly. To mitigate the problem of adjacent battery cells experiencing temperature increases when a battery cell experiences thermal runaway, this application proposes a battery device, a battery cell assembly, and an electrical device. According to the battery device, battery cell assembly, and electrical device of this application, when a battery cell is about to experience thermal runaway or has already experienced thermal runaway, the battery cell that is about to experience thermal runaway or has already experienced thermal runaway can move relative to adjacent battery cells, thereby misaligning them. This reduces the contact area between the battery cell about to experience thermal runaway or has already experienced thermal runaway and adjacent battery cells, reducing the temperature rise of adjacent battery cells and simultaneously aiding in the heat dissipation of the battery cell about to experience thermal runaway or has already experienced thermal runaway.

[0064] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0065] In some implementations, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0066] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0067] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0068] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0069] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0070] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0071] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0072] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0073] In some implementations, the energy storage device includes one or more battery clusters to increase the voltage and capacity of the energy storage device. A battery cluster may include multiple battery modules connected in series via a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0074] Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it when appropriate. For example, an energy storage device can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours. The energy storage system provided in this application can be any power system that requires energy storage devices.

[0075] The technical solutions described in this application are applicable to various electrical devices and energy storage devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, spacecraft and energy storage containers, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0076] Figure 1 This is a structural schematic diagram of vehicle 1 provided for some embodiments of this application. For example... Figure 1As shown, vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 10 is installed inside vehicle 1, and the battery device 10 can be located at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1; for example, the battery device 10 can serve as the operating power source for vehicle 1. Vehicle 1 may also include a controller 11 and a motor 12. The controller 11 is used to control the battery device 10 to supply power to the motor 12, for example, to meet the power needs of vehicle 1 during starting, navigation, and driving.

[0077] In some embodiments of this application, the battery device 10 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0078] Figure 2 This is a schematic diagram of the structure of a battery device 10 according to an embodiment of this application. Figure 3 This is a schematic diagram of the structure of a battery cell assembly 20 according to one embodiment of this application. (In conjunction with...) Figure 2 and Figure 3 As shown, to meet different power demands, the battery device 10 may include multiple battery cells 21, where each battery cell 21 is the smallest unit constituting the battery device 10. Multiple battery cells 21 can be connected in series and / or in parallel via electrode terminals for various applications. Furthermore, the multiple battery cells 21 can be connected in series, in parallel, or in a mixed configuration, where a mixed configuration refers to a combination of series and parallel connections.

[0079] Combination Figure 2 and Figure 3 As shown, the battery device 10 may include multiple battery cell assemblies 20 and a housing 30, with the multiple battery cell assemblies 20 housed inside the housing 30. The housing 30 is used to house the battery cells 21 or battery cell assemblies 20 to reduce the impact of liquids or other foreign objects on the charging or discharging of the battery cells 21. The housing 30 may be a simple three-dimensional structure such as a single cuboid, cylinder, or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders, or spheres. The material of the housing 30 may be an alloy material such as aluminum alloy or iron alloy, a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin.

[0080] In some embodiments, the housing 30 may include a first housing 301 and a second housing 302, which overlap each other, and together define a space for accommodating the battery cell 21. The second housing 302 may be a hollow structure with one end open, and the first housing 301 may be a plate-like structure, with the first housing 301 covering the open side of the second housing 302 so that the first housing 301 and the second housing 302 together define a space for accommodating the battery cell 21; alternatively, the first housing 301 and the second housing 302 may both be hollow structures with one side open, with the open side of the first housing 301 covering the open side of the second housing 302.

[0081] The battery cell assembly 20 may include multiple battery cells 21. These battery cells 21 may be connected in series, parallel, or a combination thereof to form the battery cell assembly 20. The multiple battery cell assemblies 20 may then be connected in series, parallel, or a combination thereof to form the battery device 10. The battery cell 21 may be cylindrical, flat, cuboid, or other shapes, and this application does not limit this. Battery cells 21 are generally classified into three types according to their packaging method: cylindrical battery cells, cuboid battery cells, and pouch battery cells, and this application does not limit this either. However, for the sake of brevity, the following embodiments will use a cuboid lithium-ion battery cell 21 as an example for explanation.

[0082] Figure 4 This is an exploded structural diagram of a battery cell 21 provided for some embodiments of this application. The battery cell 21 refers to the smallest unit constituting the battery device 10. For example... Figure 4 The battery cell 21 includes an end cap 211, a housing 212, and an electrode assembly 213.

[0083] End cap 211 refers to a component that covers the opening of housing 212 to isolate the internal environment of battery cell 21 from the external environment. The shape of end cap 211 can be adapted to the shape of housing 212 to fit it. Optionally, end cap 211 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap 211 is not easily deformed under pressure and impact, giving battery cell 21 higher structural strength and improved safety performance. Functional components such as electrode terminals 214 can be provided on end cap 211. Electrode terminals 214 can be used for electrical connection with electrode assembly 213 to output or input electrical energy to battery cell 21. In some embodiments, end cap 211 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of battery cell 21 reaches a threshold. In some embodiments, an insulating element may be provided on the inner side of the end cap 211. The insulating element can be used to isolate the electrical connection components inside the housing 212 from the end cap 211 to reduce the risk of short circuit. For example, the insulating element may be made of plastic, rubber, etc.

[0084] The housing 212 is a component used to cooperate with the end cap 211 to form the internal environment of the battery cell 21. This internal environment can accommodate the electrode assembly 213, electrolyte (not shown in the figure), and other components. The housing 212 and the end cap 211 can be independent components. An opening can be provided on the housing 212, and the end cap 211 can be used to close the opening to form the internal environment of the battery cell 21. Alternatively, the end cap 211 and the housing 212 can be integrated. Specifically, the end cap 211 and the housing 212 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 212, the end cap 211 closes the housing 212. The housing 212 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 212 can be determined according to the specific shape and size of the electrode assembly 213. The housing 212 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0085] Electrode assembly 213 is the component in the battery cell 21 where the electrochemical reaction occurs. The casing 212 may contain one or more electrode assemblies 213. Electrode assembly 213 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of electrode assembly 213, while the portions of the positive and negative electrode sheets without active material each constitute a tab (not shown in the figure). The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals 214 to form a current loop.

[0086] Combination Figures 2 to 5 As shown, the first aspect of this application proposes a battery device 10, including a housing 30 and a plurality of battery cells 21. The housing 30 has a receiving cavity formed inside, and the plurality of battery cells 21 are disposed in the receiving cavity. The plurality of battery cells 21 are arranged along a first direction X, and at least a portion of the battery cells 21 are spaced apart from the inner wall of the receiving cavity along a second direction Y to form an active space. The first direction X intersects the second direction Y, and at least a portion of the battery cells 21 are configured to move along the second direction Y toward the active space under the condition of thermal runaway.

[0087] Specifically, the housing 30 forms the overall external structure of the battery device 10, and its interior contains a cavity for storing battery cells 21 or other components. Multiple battery cells 21 can be arranged along the first direction X and connected in series, parallel, or mixed to form a battery cell assembly 20. For ease of description, this application only illustrates the example of multiple battery cells 21 arranged along the first direction X to form a battery cell assembly 20. The battery cells 21 have a movement space on one side along the second direction Y, allowing them to move along the second direction Y when thermal runaway occurs.

[0088] According to the battery device 10 of this application, when a battery cell 21 experiences thermal runaway, the battery cell 21 can move along the second direction Y into the active space, thereby offsetting itself from the adjacent battery cell 21 along the second direction Y. This reduces the contact area between the thermally runaway battery cell 21 and the adjacent battery cell 21 along the second direction Y, reduces the temperature rise of the adjacent battery cell 21, and helps to dissipate heat from the thermally runaway battery cell 21.

[0089] Combination Figures 2 to 5 As shown, in some embodiments of this application, at least a portion of the battery cells 21 are bonded to the inner wall of the receiving cavity or the support member in the housing 30 along the same side surface in the second direction X by an adhesive 40, and the heat distortion temperature of the adhesive 40 is less than or equal to the thermal runaway temperature of the battery cell 21.

[0090] Specifically, in some embodiments of this application, the battery device 10 includes a housing 30 and a battery cell assembly 20. The housing 30 has an internal cavity, and the battery cell assembly 20 is disposed within the cavity. The battery cell assembly 20 includes a plurality of battery cells 21 arranged along a first direction X. At least a portion of the battery cells 21 are connected to the inner wall of the housing 30 or a support member within the housing 30 via an adhesive 40 on the same side surface along a second direction Y. At least a portion of the battery cells 21 are spaced apart from the inner wall of the cavity along the other side surface along the second direction Y, thereby forming a movable space. The heat distortion temperature of the adhesive 40 is less than or equal to the thermal runaway temperature of the battery cell 21.

[0091] The housing 30 forms the overall external structure of the battery device 10, and its interior contains a cavity for storing battery cells 21 or other components. The battery cell assembly 20 is disposed within the cavity and includes a plurality of battery cells 21 arranged along a first direction X. At least a portion of the battery cells 21 are connected to a support member within the housing 30 along the same side surface in a second direction Y by an adhesive 40, thereby fixing the battery cells 21 within the cavity. Simultaneously, at least a portion of the battery cells 21 are spaced apart from the inner wall of the cavity along the other side surface in the second direction Y, thus providing sufficient space for movement of the battery cells 21 along the second direction Y. The at least a portion of the battery cells 21 may include one battery cell 21, several battery cells 21, or all battery cells 21. The support member within the housing 30 includes components disposed within and connected to the housing 30, including a heat exchange plate 50, a protective plate, or other structures for connecting and fixing the battery cells 21. For the sake of description, this application only uses the heat exchange plate 50 as the support member inside the housing 30, and all battery cells 21 are connected to the heat exchange plate 50 on the same side surface along the second direction Y by adhesive 40. The heat exchange plate 50 can exchange heat with the battery cells 21 and is used to regulate the temperature of the battery cells 21. Optionally, the first direction X can be either the length direction or the width direction of the battery cell 21. When the battery cell 21 is a cuboid battery cell, the dimension of the battery cell 21 along the length direction is larger than the dimension of the battery cell 21 along the width direction. The second direction Y can be the height direction of the battery cell 21, and electrode terminals 214 are provided in the height direction of the battery cell 21.

[0092] Adhesive 40 is a substance that bonds materials together through adhesion. Adhesive 40 connects two or more parts or materials through interfacial adhesion and cohesion. The heat resistance temperature of adhesive 40 is commonly referred to as its "heat distortion temperature." The heat distortion temperature refers to the ability of adhesive 40 to resist deformation under a certain load, and is an important indicator for evaluating the thermal stability of adhesive 40 in high-temperature environments. When adhesive 40 reaches its heat distortion temperature, it transforms from a solidified state to a viscous liquid state, leading to adhesive failure and loss of bonding strength.

[0093] By setting the heat distortion temperature of the adhesive 40 to be less than or equal to the thermal runaway temperature of the battery cell 21, when the battery cell 21 is about to experience thermal runaway or has already experienced thermal runaway, the temperature of the battery cell 21 rises and expands. At the same time, the temperature rise of the battery cell 21 causes the adhesive 40 connected to it to undergo thermal deformation and fail. After the adhesive 40 fails, it can no longer provide adhesive force to the battery cell 21. After the expanded battery cell 21 loses the adhesive effect of the adhesive, it can move in the second direction Y in a direction away from the adhesive 40, thereby offsetting itself from the adjacent battery cell 21 in the second direction Y. This reduces the contact area between the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway and the adjacent battery cell 21 in the second direction Y, reduces the temperature rise of the adjacent battery cell 21, and helps to dissipate heat from the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway.

[0094] Combination Figures 2 to 5 As shown, in some embodiments of this application, the heat distortion temperature of the adhesive 40 is greater than or equal to 80°C and less than or equal to 250°C.

[0095] Specifically, the heat distortion temperature of adhesive 40 can be any value between 80℃…150℃…200℃…250℃. When the adhesive reaches any of the above values, adhesive 40 changes from a cured state to a viscous liquid state, resulting in adhesive failure and loss of bonding strength.

[0096] The normal operating temperature of the battery cell 21 is less than 80°C. By setting the heat distortion temperature of the adhesive 40 to greater than or equal to 80°C, the adhesive force of the adhesive 40 can be improved when the battery cell 21 is operating normally, reducing the movement of the battery cell 21. However, the temperature of the battery cell 21 when thermal runaway generally reaches above 250°C. By setting the heat distortion temperature of the adhesive 40 to less than or equal to 250°C, the adhesive 40 can be thermally deformed and fail when the battery cell 21 is about to experience thermal runaway or when thermal runaway occurs, thus failing to provide adhesive force to the battery cell 21 and allowing the battery cell 21 to move along the second direction Y.

[0097] Combination Figures 2 to 5 As shown, in some embodiments of this application, the adhesive 40 includes at least one of thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive, and polyurethane adhesive.

[0098] Specifically, thermally expandable adhesives are adhesives that expand in volume when heated, including polyurethane thermally expandable adhesives, acrylate thermally expandable adhesives, ZS-1072 high-temperature resistant thermally expandable adhesives, Dow Corning SYLGARD 184 silicone rubber, and TPS butyl rubber, etc. Hot melt adhesives are adhesives that bond by melting upon heating. They are solid at room temperature, melt into a liquid state when heated to a certain temperature, and then re-cur after cooling to achieve bonding. Epoxy resin adhesives are adhesives based on epoxy resin, which cure after being mixed with a curing agent. Polyurethane adhesives are polymeric compounds whose molecular structure contains urethane groups, formed by the reaction of isocyanate groups and hydroxyl groups.

[0099] The heat distortion temperature of any one of the thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive and polyurethane adhesive can be set to be less than or equal to the thermal runaway temperature of the battery cell 21. Therefore, the adhesive 40 can be set to at least one of the thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive and polyurethane adhesive.

[0100] Combination Figures 2 to 6 As shown, in some embodiments of this application, the adhesive 40 includes a thermally expandable adhesive, which is configured such that the temperature at which expansion occurs is less than or equal to the thermal runaway temperature of the battery cell 21.

[0101] Specifically, the temperature at which a single battery cell 21 experiences thermal runaway can generally reach above 250°C. The thermal expansion adhesive is configured such that the temperature at which it expands is less than or equal to the thermal runaway temperature of the single battery cell 21, that is, the thermal deformation temperature of the thermal expansion adhesive is less than or equal to the thermal runaway temperature of the single battery cell 21. Optionally, the thermal deformation temperature of the thermal expansion adhesive can be any value between 80°C…150°C…200°C…250°C.

[0102] By setting the adhesive 40 as a thermally expandable adhesive, and configuring the thermally expandable adhesive to expand at a temperature less than or equal to the thermal runaway temperature of the battery cell 21, when the battery cell 21 is about to experience thermal runaway or has already experienced thermal runaway, the adhesive 40 connected to it can not only undergo thermal deformation and fail, resulting in the loss of adhesion to the battery cell 21, but also expand when heated. This expands the adhesive 40, which then pushes the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway in a direction away from the adhesive 40, thereby reducing the contact area between the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway and the adjacent battery cell 21 along the second direction Y.

[0103] Combination Figures 2 to 6 As shown, in some embodiments of this application, the thermally expandable adhesive is configured to thermally expand when the temperature reaches 200°C, and the volume after expansion is 3 to 5 times the volume before expansion.

[0104] Specifically, the heat distortion temperature of the thermally expanding adhesive can be set to 200℃. When the battery cell 21 experiences thermal runaway and heats up, the thermally expanding adhesive connected to the battery cell 21 heats up. When the temperature of the thermally expanding adhesive reaches 200℃, it expands, and its volume after expansion is 3 to 5 times its original volume. Since the adhesive 40 is connected to the heat exchange plate 50 and the battery cell 21 on both sides along the second direction Y, and the heat exchange plate 50 is fixed inside the housing 30 and its position remains unchanged, when the adhesive 40 expands, the battery cell 21 connected to the adhesive 40 is pushed up along the second direction Y in a direction away from the heat exchange plate 50 under the action of the expanded adhesive 40, thus offsetting itself from the adjacent battery cell 21 along the second direction Y. Figure 6 The adhesive 40 includes a first part 41 and a second part 42. The battery cell 21 corresponding to the second part 42 is a battery cell 21 in a thermal runaway state, and thus the second part 42 expands due to heat. The battery cell 21 corresponding to the first part 41 is a battery cell in a normal state, therefore the first part 41 does not expand.

[0105] Combination Figures 2 to 6 As shown, in some embodiments of this application, the battery device 10 further includes a heat exchange plate 50, which is disposed in the receiving cavity and forms a support member. At least a portion of the battery cells 21 are connected to the heat exchange plate 50 along the same side surface in the second direction Y by an adhesive 40.

[0106] Specifically, the heat exchange plate 50 can be located at the top or bottom of the battery cell 21, in which case the second direction Y is vertical, depending on the installation position. At least a portion of the battery cells 21 are connected to the heat exchange plate 50 along the same side surface of the second direction Y by adhesive 40, and at least a portion of the battery cells 21 are spaced apart from the inner wall of the receiving cavity along the other side surface of the second direction Y, thereby facilitating the movement of the battery cells 21 along the second direction Y in the event of thermal runaway.

[0107] In some embodiments of this application, the heat exchange plate 50 may also be arranged horizontally on the side of the battery cell 21 and connected to the battery cell 21 by an adhesive 40, in which case the second direction Y is horizontal. Alternatively, the battery cell 21 may be connected horizontally to the inner wall of the housing 30 by an adhesive 40.

[0108] The heat exchange plate 50 is located inside the cavity and can exchange heat with the battery cell 21, thereby regulating the temperature of the battery cell 21. At the same time, the surface of the heat exchange plate 50 is convenient for bonding and fixing the battery cell 21 with adhesive 40.

[0109] Combination Figures 2 to 6As shown, in some embodiments of this application, the battery cell 21 includes a first surface 2121 with the largest area, and a first direction X is perpendicular to the first surface 2121.

[0110] Specifically, the battery cell 21 includes a length direction, a width direction, and a height direction. The dimensions of the battery cell 21 along the length direction and along the height direction are both larger than the dimension along the width direction. The surface where the length and height directions of the battery cell 21 meet is the first surface 2121 of the battery cell 21. The first surface 2121 is perpendicular to the first direction X, meaning that the first surfaces 2121 of two adjacent battery cells 21 are positioned opposite each other along the first direction X, and the width direction of the battery cell 21 coincides with the first direction X.

[0111] By arranging the first surface 2121 perpendicular to the first direction X and arranging the multiple battery cells 21 along the first direction X, the size of the battery cells 21 along the first direction X can be reduced, thereby increasing the number of battery cells 21 arranged in the battery cell assembly 20 along the first direction X.

[0112] Combination Figures 7 to 9 As shown, in some embodiments of this application, at least a portion of the battery cells 21 include a support portion 216 and a deformable portion 217 arranged sequentially along the second direction Y, wherein the deformable portion 217 has a greater deformability along the first direction X than the support portion 216 has a greater deformability along the first direction X, and the side where the support portion 216 is located has a space for movement.

[0113] Specifically, the housing 212 includes a support portion 216 and a deformable portion 217 arranged sequentially along the second direction Y. The support portion 216 is located on the side of the deformable portion 217 away from the support member, and a movable space is formed on the side where the support portion 216 is located, allowing the battery cell 21 to move towards the side away from the support member. When the temperature of the battery cell 21 rises, the deformation of the deformable portion 217 along the first direction X is greater than the deformation of the support portion 216 along the first direction X. This allows adjacent battery cells 21 to be compressed along the side closer to the support member, causing the compressed battery cells 21 to move towards the side where the support portion 216 is located. Optionally, by adjusting the structure or composition of the deformable portion 217, its deformation capability along the first direction X can be improved compared to the support portion 216.

[0114] When a battery cell 21 experiences thermal runaway, the active material within the battery cell 21 reacts and decreases. When the pressure inside the battery cell 21 reaches a certain level, the pressure relief mechanism 215 of the battery cell 21 opens and releases the pressure inside the battery cell 21, resulting in a decrease in the internal pressure of the battery cell 21 experiencing thermal runaway. At the same time, the temperature of the battery cell 21 in the normal state adjacent to the battery cell 21 experiencing thermal runaway increases. Since the battery cell 21 includes a support portion 216 and a deformation portion 217 arranged sequentially along the second direction Y, and the deformation capacity of the deformation portion 217 along the first direction X is greater than the deformation capacity of the support portion 216 along the first direction X, and there is a space for movement on the side where the support portion 216 is located, the deformation portion 217 of the battery cell 21 in the normal state after being heated can expand and deform towards the direction of the battery cell 21 experiencing thermal runaway, and squeeze the battery cell 21 experiencing thermal runaway, thereby causing the battery cell 21 experiencing thermal runaway to move along the second direction Y in a direction away from the adhesive 40.

[0115] Combination Figures 7 to 9 As shown, in some embodiments of this application, the deformable portion 217 has a recessed portion 21211 on its surface along the first direction X, and the recessed portion 21211 extends along the third direction Z, with the first direction X, the second direction Y and the third direction Z being perpendicular to each other.

[0116] Specifically, the recess 21211 is formed on the surface of the housing 212 and can be obtained by removing part of the wall thickness from the formed housing 212. Therefore, the wall thickness of the recess 21211 is smaller than the wall thickness of the housing 212 on both sides of the recess 21211 along the second direction Y, making it easier to bend. Optionally, the first direction X can be the width direction of the battery cell 21, the third direction Z can be the length direction of the battery cell 21, and the second direction Y can be the height direction of the battery cell 21. The dimension of the battery cell 21 along the length direction is larger than the dimension along the width direction, and the battery cell 21 has electrode terminals 214 in the height direction.

[0117] Optionally, at least a portion of the battery cells 21 may also be provided with a pressure relief mechanism 215 on the other side surface along the second direction Y. The pressure relief mechanism 215 is configured to open and release the pressure inside the battery cell 21 when the internal pressure of the battery cell 21 reaches a preset value. Optionally, the pressure relief mechanism 215 may be a pressure relief valve.

[0118] When a battery cell 21 experiences thermal runaway, the deformable portion 217 has a recessed portion 21211 on its surface along the first direction X, and the recessed portion 21211 extends along the third direction Z. The wall thickness of the battery cell 21 at the position corresponding to the recessed portion 21211 is less than the wall thickness of the battery cells 21 on both sides of the recessed portion 21211 along the second direction Y. Therefore, the battery cell 21 in its normal state after being heated can expand and deform toward the direction of the battery cell 21 that has experienced thermal runaway, and the portion of the recessed portion 21211 on both sides of the second direction Y bends and deforms around the third direction Z, thereby squeezing the battery cell 21 that has experienced thermal runaway, and causing the battery cell 21 that has experienced thermal runaway to move along the second direction Y toward the direction away from the adhesive 40.

[0119] Combination Figures 7 to 9 As shown, in some embodiments of this application, the battery cell 21 includes two first surfaces 2121 disposed opposite to each other along a first direction X, and the battery cell 21 also includes two second surfaces 2122 disposed opposite to each other along a third direction Z. At least one first surface 2121 is provided with a recess 21211, and the recess 21211 penetrates through the second surfaces 2122 on both sides along the third direction Z.

[0120] Specifically, the battery cell 21 can be a cuboid battery cell, including two first surfaces 2121 arranged opposite each other along a first direction X, and two second surfaces 2122 arranged opposite each other along a third direction Z. Each of the two first surfaces 2121 has a recess 21211 extending along the third direction Z, and the recess 21211 penetrates both sides of the second surfaces 2122 along the third direction Z, that is, the recess 21211 is a through groove penetrating the housing 212 along the third direction Z.

[0121] By extending the recessed portion 21211 through the second surface 2122 on both sides along the third direction Z, the bending deformation capability of the first surface 2121 around the third direction Z can be improved, thereby facilitating the movement of the battery cell 21 in the normal state after thermal expansion along the second direction Y to push the thermally runaway battery cell 21.

[0122] Combination Figures 7 to 9 As shown, in some embodiments of this application, the first surface 2121 is provided with a plurality of recesses 21211 along the second direction Y on the side close to the adhesive 40, and the plurality of recesses 21211 are spaced apart and arranged in parallel along the second direction Y.

[0123] Specifically, there are multiple recesses 21211, and the multiple recesses 21211 are arranged parallel to and spaced apart along the second direction Y on the side of the first surface 2121 near the adhesive 40.

[0124] By arranging multiple recesses 21211 in parallel along the second direction Y, the bending deformation capability of the first surface 2121 around the third direction Z can be improved, thereby facilitating the movement of the battery cell 21 in its normal state after thermal expansion along the second direction Y, which pushes the thermally runaway battery cell 21.

[0125] Combination Figure 2 , Figure 10 and Figure 11 As shown, in some embodiments of this application, the battery device 10 includes a battery cell assembly 20, which includes a frame 22 and a plurality of battery cells 21. The frame 22 is a housing for accommodating the plurality of battery cells 21. An installation cavity is formed inside the frame 22. The plurality of battery cells 21 are disposed in the installation cavity and arranged along a first direction X. At least a portion of the battery cells 21 are connected to the inner wall of the installation cavity along the same side surface along a second direction Y by an adhesive 40. The heat distortion temperature of the adhesive 40 is less than or equal to the thermal runaway temperature of the battery cell 21. The first direction X intersects the second direction Y.

[0126] Specifically, the frame 22 forms the overall external structure of the battery cell assembly 20, and its interior forms a mounting cavity for storing battery cells 21 or other components. The frame 22 includes two end plates 221 that are opposite to each other and spaced apart along a first direction X, and a bottom plate 222 that is disposed on at least one side of the end plates 221 along a second direction Y. The end plates 221 and the bottom plate 222 on both sides enclose the mounting cavity, which is open at the top along the second direction Y. In some other embodiments of this application, the frame 22 may also include two side plates that are opposite to each other and spaced apart along a third direction Z. By placing multiple battery cells 21 within the frame 22, it is convenient to assemble the battery cell assembly 20 into the battery device 10. The multiple battery cells 21 are respectively disposed within the mounting cavity and arranged along the first direction X. At least a number of battery cells 21 are connected to the base plate 222 on the same side surface along the second direction Y by adhesive 40, thereby fixing the battery cells 21 in the mounting cavity. At the same time, at least a number of battery cells 21 are arranged with the other side surface along the second direction Y facing the opening, so that the battery cells 21 have sufficient movement space along the second direction Y. The at least a number of battery cells 21 may include one battery cell 21, several battery cells 21, or all battery cells 21.

[0127] Optionally, the first direction X can be either the length direction or the width direction of the battery cell 21. When the battery cell 21 is a cuboid battery cell, the dimension of the battery cell 21 along the length direction is larger than the dimension of the battery cell 21 along the width direction. The second direction Y can be the height direction of the battery cell 21, and the battery cell 21 is provided with electrode terminals 214 in the height direction.

[0128] Adhesive 40 is a substance that bonds materials together through adhesion. Adhesive 40 connects two or more parts or materials through interfacial adhesion and cohesion. The heat resistance temperature of adhesive 40 is commonly referred to as its "heat distortion temperature." The heat distortion temperature refers to the ability of adhesive 40 to resist deformation under a certain load, and is an important indicator for evaluating the thermal stability of adhesive 40 in high-temperature environments. When adhesive 40 reaches its heat distortion temperature, it transforms from a solidified state to a viscous liquid state, leading to adhesive failure and loss of bonding strength.

[0129] According to the battery device 10 of this application, by setting the heat distortion temperature of the adhesive 40 to be less than or equal to the thermal runaway temperature of the battery cell 21, when the battery cell 21 is about to experience thermal runaway or has already experienced thermal runaway, the temperature of the battery cell 21 rises and expands. At the same time, the temperature rise of the battery cell 21 causes the adhesive 40 connected to it to undergo thermal deformation and fail. After the adhesive 40 fails, it can no longer provide adhesive force to the battery cell 21. After the expanded battery cell 21 loses the adhesive effect of the adhesive, it can move in the second direction Y in a direction away from the adhesive 40, thereby offsetting itself from the adjacent battery cell 21 in the second direction Y. This reduces the contact area between the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway and the adjacent battery cell 21 in the second direction Y, reduces the temperature rise of the adjacent battery cell 21, and helps to dissipate heat from the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway.

[0130] Combination Figure 10 and Figure 11 As shown, in some embodiments of this application, the adhesive 40 includes a thermally expandable adhesive, which is configured such that the temperature at which expansion occurs is less than or equal to the thermal runaway temperature of the battery cell 21.

[0131] Specifically, the temperature at which a single battery cell 21 experiences thermal runaway can generally reach above 250°C. The thermal expansion adhesive is configured such that the temperature at which it expands is less than or equal to the thermal runaway temperature of the single battery cell 21, that is, the thermal deformation temperature of the thermal expansion adhesive is less than or equal to the thermal runaway temperature of the single battery cell 21. Optionally, the thermal deformation temperature of the thermal expansion adhesive can be any value between 80°C…150°C…200°C…250°C.

[0132] By setting the adhesive 40 as a thermally expandable adhesive, and configuring the thermally expandable adhesive to expand at a temperature less than or equal to the thermal runaway temperature of the battery cell 21, when the battery cell 21 is about to experience thermal runaway or has already experienced thermal runaway, the adhesive 40 connected to it can not only undergo thermal deformation and fail, resulting in the loss of adhesion to the battery cell 21, but also expand when heated. This expands the adhesive 40, which then pushes the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway in a direction away from the adhesive 40, thereby reducing the contact area between the battery cell 21 that is about to experience thermal runaway or has already experienced thermal runaway and the adjacent battery cell 21 along the second direction Y.

[0133] Combination Figure 8 , Figure 10 , Figure 12 and Figure 13 As shown, in some embodiments of this application, at least a portion of the battery cells 21 have recesses 21211 on their surfaces along the first direction X. The recesses 21211 extend along the third direction Z, and the first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0134] Specifically, the recess 21211 is formed on the surface of the housing 212 and can be obtained by removing part of the wall thickness from the formed housing 212. Therefore, the wall thickness of the recess 21211 is smaller than the wall thickness of the housing 212 on both sides of the recess 21211 along the second direction Y, making it easier to bend. Optionally, the first direction X can be the width direction of the battery cell 21, the third direction Z can be the length direction of the battery cell 21, and the second direction Y can be the height direction of the battery cell 21. The dimension of the battery cell 21 along the length direction is larger than the dimension along the width direction, and the battery cell 21 has electrode terminals 214 in the height direction.

[0135] Optionally, at least a portion of the battery cells 21 may also be provided with a pressure relief mechanism 215 on the other side surface along the second direction Y. The pressure relief mechanism 215 is configured to open and release the pressure inside the battery cell 21 when the internal pressure of the battery cell 21 reaches a preset value. Optionally, the pressure relief mechanism 215 may be a pressure relief valve.

[0136] When a thermal runaway occurs in a battery cell 21, the active material inside the battery cell 21 reacts and decreases. When the pressure inside the battery cell 21 reaches a certain level, the pressure relief mechanism 215 of the battery cell 21 opens and releases the pressure inside the battery cell 21, causing the internal pressure of the thermally runaway battery cell 21 to decrease. At the same time, the temperature of the normally functioning battery cell 21 adjacent to the thermally runaway battery cell 21 rises. Because the surface of the battery cell 21 along the first direction X has a recess 21211, and the recess 21211 along the third direction... Extending towards Z, the wall thickness of the battery cell 21 at the corresponding position of the recess 21211 is less than the wall thickness of the battery cells 21 on both sides of the recess 21211 along the second direction Y. Therefore, the battery cell 21 in the normal state after being heated can expand and deform in the direction of the battery cell 21 that has experienced thermal runaway, and cause the portion of the recess 21211 on both sides of the second direction Y to bend and deform around the third direction Z, thereby squeezing the battery cell 21 that has experienced thermal runaway, and causing the battery cell 21 that has experienced thermal runaway to move in the direction away from the adhesive 40 along the second direction Y.

[0137] Combination Figure 8 , Figure 10 , Figure 12 and Figure 13 As shown, in some embodiments of this application, the battery cell 21 includes two first surfaces 2121 disposed opposite to each other along a first direction X, and the battery cell 21 also includes two second surfaces 2122 disposed opposite to each other along a third direction Z. At least one first surface 2121 is provided with a recess 21211, and the recess 21211 penetrates through the second surfaces 2122 on both sides along the third direction Z.

[0138] Specifically, the battery cell 21 can be a cuboid battery cell, including two first surfaces 2121 arranged opposite each other along a first direction X, and two second surfaces 2122 arranged opposite each other along a third direction Z. Each of the two first surfaces 2121 has a recess 21211 extending along the third direction Z, and the recess 21211 penetrates both sides of the second surfaces 2122 along the third direction Z, that is, the recess 21211 is a through groove penetrating the housing 212 along the third direction Z.

[0139] By extending the recessed portion 21211 through the second surface 2122 on both sides along the third direction Z, the bending deformation capability of the first surface 2121 around the third direction Z can be improved, thereby facilitating the movement of the battery cell 21 in the normal state after thermal expansion along the second direction Y to push the thermally runaway battery cell 21.

[0140] Combination Figure 8 , Figure 10 , Figure 12 and Figure 13As shown, in some embodiments of this application, the battery cell 21 includes a first surface 2121 with the largest area, and a first direction X is perpendicular to the first surface 2121.

[0141] Specifically, the battery cell 21 includes a length direction, a width direction, and a height direction. The dimensions of the battery cell 21 along the length direction and along the height direction are both larger than the dimension along the width direction. The surface where the length and height directions of the battery cell 21 meet is the first surface 2121 of the battery cell 21. The first surface 2121 is perpendicular to the first direction X, meaning that the first surfaces 2121 of two adjacent battery cells 21 are positioned opposite each other along the first direction X, and the width direction of the battery cell 21 coincides with the first direction X.

[0142] By arranging the first surface 2121 perpendicular to the first direction X and arranging the multiple battery cells 21 along the first direction X, the size of the battery cells 21 along the first direction X can be reduced, thereby increasing the number of battery cells 21 arranged in the battery cell assembly 20 along the first direction X.

[0143] Combination Figure 1 and Figure 2 As shown, a second aspect of this application also proposes an electrical device, which includes the battery device 10 of any of the above embodiments.

[0144] Since the electrical device in this application has the same technical features as the battery device 10 in any of the above embodiments and can achieve the same technical effect, it will not be described again here.

[0145] Combination Figure 1 and Figure 2 As shown, in some embodiments of this application, the electrical device can be a vehicle 1, which includes a battery device 10 according to any of the above embodiments. The battery device 10 is used to provide electrical energy to the vehicle 1 and to drive the vehicle 1 to move.

[0146] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application.

[0147] Combination Figures 1 to 9As shown, in some embodiments of this application, the battery device 10 includes a housing 30, a battery cell assembly 20, and a heat exchange plate 50. The housing 30 has an internal cavity, within which the battery cell assembly 20 and the heat exchange plate 50 are disposed. The battery cell assembly 20 includes a plurality of battery cells 21 arranged along a first direction X. At least a portion of the battery cells 21 are connected to the heat exchange plate 50 via an adhesive 40 on the same side surface along a second direction Y. At least a portion of the battery cells 21 are spaced apart from the inner wall of the cavity along the other side surface along the second direction Y, forming a movable space. At least a portion of the battery cells 21 are configured to move along the second direction Y into the movable space under thermal runaway conditions. The heat distortion temperature of the adhesive 40 is less than or equal to the thermal runaway temperature of the battery cell 21. The adhesive 40 includes a thermally expandable adhesive, which is configured to expand thermally when the temperature reaches 200°C, and the expanded volume is 3 to 5 times the original volume.

[0148] The battery cell 21 includes two first surfaces 2121 arranged opposite each other along a first direction X. The first surface 2121 is the surface with the largest area of ​​the battery cell 21, and the first direction X is perpendicular to the first surface 2121. The battery cell 21 also includes two second surfaces 2122 arranged opposite each other along a third direction Z. At least one first surface 2121 has a plurality of recesses 21211 on the side of the adhesive 40 along the second direction Y. The plurality of recesses 21211 are spaced apart and parallel along the second direction Y, and any one of the recesses 21211 penetrates through both sides of the second surface 2122 along the third direction Z. The first direction X, the second direction Y, and the third direction Z are all perpendicular to each other. The first direction X is the width direction of the battery cell 21, the second direction Y is the height direction of the battery cell 21, and the third direction Z is the length direction of the battery cell 21. An electrode terminal 214 and a pressure relief mechanism 215 are provided on the side of the battery cell 21 facing away from the adhesive 40 in the height direction.

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery device, characterized in that, include: The box body has an internal cavity for receiving; Multiple battery cells are disposed within the receiving cavity, and the multiple battery cells are arranged along a first direction. At least a portion of the battery cells are spaced apart from the inner wall of the receiving cavity along one side of a second direction to form an active space. The first direction intersects the second direction, and at least a portion of the battery cells are configured to move along the second direction toward the active space under the condition of thermal runaway.

2. The battery device according to claim 1, characterized in that, At least a portion of the battery cells are bonded to the inner wall of the receiving cavity or the support member inside the box via an adhesive along the same side surface in the second direction, wherein the heat distortion temperature of the adhesive is less than or equal to the thermal runaway temperature of the battery cell.

3. The battery device according to claim 2, characterized in that, The heat distortion temperature of the adhesive is greater than or equal to 80°C and less than or equal to 250°C.

4. The battery device according to claim 2, characterized in that, The adhesive includes at least one of thermal expansion adhesive, hot melt adhesive, epoxy resin adhesive, and polyurethane adhesive.

5. The battery device according to claim 2, characterized in that, The adhesive includes a thermally expandable adhesive, which is configured such that the temperature at which expansion occurs is less than or equal to the thermal runaway temperature of the battery cell.

6. The battery device according to claim 5, characterized in that, The thermally expandable adhesive is configured to expand thermally when the temperature reaches 200°C, and the volume after expansion is 3 to 5 times the volume before expansion.

7. The battery device according to claim 2, characterized in that, The battery device further includes a heat exchange plate that forms the support member, and at least a portion of the battery cells are connected to the heat exchange plate via the adhesive on the same side surface along the second direction.

8. The battery device according to claim 1, characterized in that, The battery cell includes a first surface with the largest area, and the first direction is perpendicular to the first surface.

9. The battery device according to any one of claims 1 to 8, characterized in that, At least a portion of the battery cells include a support portion and a deformable portion arranged sequentially along the second direction, wherein the deformable portion has a greater deformable capacity along the first direction than the support portion has a greater deformable capacity along the first direction, and the side where the support portion is located has the movable space.

10. The battery device according to claim 9, characterized in that, The deformable portion has a recessed portion on its surface along the first direction, and the recessed portion extends along a third direction, with the first direction, the second direction, and the third direction being perpendicular to each other.

11. The battery device according to claim 10, characterized in that, The battery cell includes two first surfaces disposed opposite each other along the first direction, and the battery cell also includes two second surfaces disposed opposite each other along the third direction. At least one of the first surfaces is provided with the recessed portion, and the recessed portion penetrates the second surfaces on both sides along the third direction.

12. The battery device according to claim 11, characterized in that, The first surface has a plurality of recesses on the side near the adhesive along the second direction, and the plurality of recesses are spaced apart and arranged in parallel along the second direction.

13. An electrical appliance, characterized in that, The battery device includes any one of claims 1 to 12.

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