Box body, battery device and electric equipment

Abstract

The invention is suitable for the technical field of batteries, and provides a box body, a battery device and electric equipment. The battery device comprises a box body and a battery monomer, the box body comprises a box body, the box body comprises an enclosure bulkhead and a first cover plate, the enclosure bulkhead comprises a fixed section and an expansion section which are distributed in the first direction, the first direction is perpendicular to the first cover plate, the first cover plate is connected to the end, away from the fixed section, of the expansion section, and the first cover plate and the enclosure bulkhead jointly define a containing space; the expansion section can be expanded along the first direction when the air pressure in the accommodating space is greater than a threshold value, the battery monomer is arranged in the accommodating space, and the battery monomer is provided with a pressure relief mechanism which faces the first cover plate. According to the technical scheme provided by the embodiment of the invention, the technical problem that out-of-control spurts generated by the battery monomers in the related technology are easy to gather in the box body can be solved, so that the safety of the battery device is improved.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a box, a battery device and electrical equipment. Background Art

[0002] The battery pack is an energy storage unit used in new energy vehicles, energy storage systems and other equipment, and its safety issues are particularly important. The battery pack includes a box and multiple battery cells arranged in the box. Once the battery cells experience thermal runaway, a large amount of uncontrolled spray will be generated. If these uncontrolled sprays cannot be discharged to the outside in time, they are easy to accumulate in the box, posing a major safety hazard. Summary of the invention

[0003] In view of this, the embodiments of the present application provide a box, a battery device and an electrical device, which can improve the safety of the battery device.

[0004] An embodiment of the first aspect of the present application provides a battery device, including: a box body, including a box body, the box body including a surrounding wall and a first cover plate, the surrounding wall including a fixed section and an extended section distributed along a first direction, the first direction is perpendicular to the first cover plate, the first cover plate is connected to an end of the extended section away from the fixed section, the first cover plate and the surrounding wall together enclose a accommodating space, and the extended section can be expanded along the first direction when the air pressure in the accommodating space is greater than a threshold value; a battery cell, arranged in the accommodating space, the battery cell has a pressure relief mechanism and the pressure relief mechanism faces the first cover plate.

[0005] In the battery device provided in the above embodiment, the surrounding wall of the box body includes a fixed section and an expansion section, and the expansion section can be expanded along a first direction when the air pressure in the accommodating space is greater than a threshold value. In this way, when the battery cell undergoes thermal runaway and releases uncontrolled spray into the accommodating space, as the air pressure in the accommodating space increases, the first cover plate can move in a direction away from the battery cell and form a discharge channel between the battery cell and the first cover plate. Since the height of the discharge channel in the first direction is relatively large, sufficient moving space and a smooth discharge path can be provided for the spray, thereby reducing the risk of the spray impacting adjacent battery cells and gathering and clogging in the box body, thereby improving the reliability and safety of the battery device.

[0006] In some embodiments, the expansion segment includes a telescopic portion that can move along the first direction, and / or the expansion segment includes a deformable portion that can be stretched and deformed along the first direction.

[0007] In the above design, the expansion section has a reasonable structure, and the box can achieve space expansion through simple telescoping or deformation.

[0008] In some embodiments, the expansion section includes a plurality of folding plates, which are bent and connected to form folds extending along a second direction at the connection points, and the second direction is perpendicular to the first direction.

[0009] In the above design, the structure of the surrounding wall extension section is simple, and the height variation range of the extension section in the folded state and the unfolded state is large, so it has high practicality.

[0010] In some embodiments, the elongation at break X of the folding plate is ≥30%, and / or the elastic modulus E of the folding plate is ≤100 GPa.

[0011] In the above design, the folded plate has good ductility or plasticity, meeting the design requirements of the expansion section.

[0012] In some embodiments, the box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall or the first cover plate. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

[0013] In the above design, by providing a pressure balancing mechanism, the safety of the battery device can be further improved.

[0014] In some embodiments, the box body also includes a support plate arranged in the accommodating space, the support plate is arranged in the accommodating space and opposite to the first cover plate, the support plate divides the accommodating space into a first part and a second part distributed along a first direction, the battery cell is accommodated in the first part, and a first through hole connecting the first part and the second part is provided on the support plate.

[0015] In the above design, the support plate has a high structural strength and can provide stable and reliable support for the battery cell. At the same time, the support plate divides the accommodating space into a first part and a second part, which can isolate the battery cell from liquid or solid spray along a first direction, further reducing the risk of the spray impacting the battery cell.

[0016] In some embodiments, the box body also includes a partition, which is vertically arranged on the side of the support plate away from the first cover plate and divides the first part into a third part and a fourth part. The battery cell is accommodated in the third part, and the first through hole connects the second part and the third part.

[0017] In the above design, the support plate and the partition plate can be used to define an independent space within the accommodating space to store the battery cells, further reducing the risk of the spray impacting the battery cells.

[0018] In some embodiments, the support plate is further provided with a second through hole connecting the second portion and the fourth portion.

[0019] In the above design, the through holes are used to connect the various parts in the box, which is conducive to keeping the pressure of various parts in the box consistent, thereby further improving the safety of the battery device.

[0020] In some embodiments, the box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall opposite to the fourth part. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

[0021] In the above design, the support plate and the partition are used to define an independent discharge channel in the accommodating space, which further reduces the risk of the spray impacting the battery cell.

[0022] In some embodiments, the box body further includes a second cover plate, the second cover plate is connected to an end of the fixed section away from the expansion section, and the first cover plate, the second cover plate and the surrounding wall together form a accommodating space.

[0023] In the above design, the first cover plate, the second cover plate and the surrounding wall together form a closed accommodating space, and the box body has good sealing performance, which can effectively prevent moisture, dust or other pollutants from entering the interior of the box body.

[0024] An embodiment of the second aspect of the present application provides a box body for use in a battery device, the battery device includes a battery cell, the box body includes a box body, the box body includes a surrounding wall and a first cover plate, the surrounding wall includes a fixed section and an extended section distributed along a first direction, the first direction is perpendicular to the first cover plate, the first cover plate is connected to an end of the extended section away from the fixed section, the first cover plate and the surrounding wall together form a accommodating space for placing the battery cell, and the extended section can be expanded along the first direction when the air pressure in the accommodating space is greater than a threshold value.

[0025] In the box provided by the above embodiment, the surrounding wall of the box body includes a fixed section and an expansion section, and the expansion section can be expanded along a first direction when the air pressure in the accommodating space is greater than a threshold value. In this way, when the battery cell undergoes thermal runaway and releases uncontrolled spray into the accommodating space, as the air pressure in the accommodating space increases, the first cover plate can move in a direction away from the battery cell and form a discharge channel between the battery cell and the first cover plate. Since the height of the discharge channel in the first direction is relatively large, sufficient moving space and a smooth discharge path are provided for the spray, thereby reducing the risk of the spray impacting adjacent battery cells and gathering and clogging in the box. The reliability and safety of storing battery cells in the box are higher.

[0026] In some embodiments, the expansion segment includes a telescopic portion that can move along the first direction, and / or the expansion segment includes a deformable portion that can be stretched and deformed along the first direction.

[0027] In the above design, the expansion section has a reasonable structure, and the box can achieve space expansion through simple telescoping or deformation.

[0028] In some embodiments, the expansion section includes a plurality of folding plates, which are bent and connected to form folds extending along a second direction at the connection points, and the second direction is perpendicular to the first direction.

[0029] In the above design, the structure of the surrounding wall extension section is simple, and the height variation range of the extension section in the folded state and the unfolded state is large, so it has high practicality.

[0030] In some embodiments, the elongation at break X of the folding plate is ≥30%, and / or the elastic modulus E of the folding plate is ≤100 GPa.

[0031] In the above design, the folded plate has good ductility or plasticity, meeting the design requirements of the expansion section.

[0032] In some embodiments, the box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall or the first cover plate. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

[0033] In the above design, by providing a pressure balancing mechanism, the safety of the battery device can be further improved.

[0034] In some embodiments, the box body further includes a second cover plate, the second cover plate is connected to an end of the fixed section away from the expansion section, and the first cover plate, the second cover plate and the surrounding wall together form a accommodating space.

[0035] In the above design, the first cover plate, the second cover plate and the surrounding wall together form a closed accommodating space, and the box body has good sealing performance, which can effectively prevent moisture, dust or other pollutants from entering the interior of the box body.

[0036] An embodiment of the third aspect of the present application provides an electrical device, including the battery device provided by the embodiments of the first aspect.

[0037] The electrical equipment provided in the above embodiment improves the reliability and safety of the electrical equipment by adopting the battery device in the first aspect.

[0038] 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

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or conventional technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 is a schematic structural diagram of a vehicle provided in an embodiment of the present application; Figure 2 is an exploded view of a battery device provided in an embodiment of the present application; Figure 3 is a schematic diagram of the structure of a battery cell provided in an embodiment of the present application; Figure 4 yes Figure 3 An exploded view of the battery cell shown; Figure 5 yes Figure 3 A schematic diagram of the structure of the battery cell shown in another viewing angle; Figure 6 is a cross-sectional view of a battery device provided in an embodiment of the present application; Figure 7 is a partial structural schematic diagram of a battery device provided in one embodiment of the present application; Figure 8 is a partial structural schematic diagram of a battery device provided by another embodiment of the present application, wherein the extended section of the surrounding wall is in a folded state; Fig. 9 1 is a schematic diagram of a partial structure of a battery device provided in another embodiment of the present application, wherein the extended section of the surrounding wall is in an expanded state.

[0041] The meanings of the marks in the figure are: 1000, vehicle; 100, battery device; 200, controller; 300, motor; 10. Box body; 101. Box body; 102. Pressure balancing mechanism; 11. surrounding wall; 111. fixed section; 112. expansion section; 12. first cover plate; 13. second cover plate; 14. folding plate; 141. first folding plate; 142. second folding plate; 15. crease; 16. support plate; 161. first through hole; 162. second through hole; 17. first part; 171. third part; 172. fourth part; 18. second part; 19. partition; 20. Battery cell; 21. End cover; 21a. Electrode terminal; 22. Shell; 23. Electrode assembly; 23a. Tab; 24. Pressure relief mechanism. DETAILED DESCRIPTION

[0042] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0044] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0045] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0046] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0047] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0048] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0049] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0050] The battery pack includes a box body and a plurality of battery cells arranged in the box body, wherein a pressure balancing mechanism is arranged on the box body and a pressure relief mechanism is arranged on the battery cells. When a battery cell has thermal runaway, the pressure relief mechanism opens, generates uncontrolled spray and sprays into the box body, and when the pressure inside the box body exceeds the safety range, the pressure balancing mechanism opens and releases the pressure.

[0051] The spray includes not only gas, but also some liquid or solid impurities, such as decomposition products of electrolyte and electrode materials. These sprays have very high temperature and energy. If there is not enough discharge space in the box, the sprays are easy to impact the adjacent battery cells or get stuck inside the box, which will cause thermal runaway and spread, and even cause fire or explosion.

[0052] In the current battery pack design, a gap is reserved between the battery cell and the inner wall of the box, forming a discharge channel. However, in order to pursue higher volume energy density, the gap between the battery cell and the inner wall of the box is compressed to the extreme, generally limited to the millimeter level, which is not conducive to the smooth discharge of the spray.

[0053] Based on the above considerations, an embodiment of the present application provides a battery device with an improved structure of the box body. By designing an expansion section on the wall of the box body, the expansion section is expanded when the air pressure in the accommodation space of the box body is greater than a threshold value to increase the volume of the accommodation space. This can effectively reduce the risk of spray released by the battery cell impacting adjacent battery cells and gathering and clogging in the box, thereby improving the reliability and safety of the battery device.

[0054] The battery device provided in the embodiment of the present application can be used in various energy storage systems that use the battery device as a power source or use the battery device as an energy storage element. The electrical equipment can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, a battery car, an electric car, a ship, a spacecraft, and the like. 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, and the like, and the spacecraft can include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0055] For the convenience of explanation, the embodiment of the present application is described by taking an electrical device as a vehicle 1000 as an example.

[0056] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000, for example, the battery device 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0057] In some embodiments of the present application, the battery device 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0058] Please refer to Figure 2 , Figure 2 An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a housing 10 and a battery cell 20, and the battery cell 20 is accommodated in the housing 10. Among them, the housing 10 is used to provide a storage space for the battery cell 20, and the housing 10 can adopt a variety of structures. In some embodiments, the housing 10 can be used as a part of the chassis structure of the vehicle 1000. For example, a part of the housing 10 can become at least a part of the floor of the vehicle 1000, or a part of the housing 10 can become at least a part of the crossbeam and longitudinal beam of the vehicle 1000.

[0059] In the battery device 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; or, the multiple battery cells 20 may be first connected in series, in parallel, or in a mixed connection to form a battery cell assembly, and the multiple battery cell assemblies are then connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery device 100 may also include other structures, for example, the battery device 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0060] The battery cell 20 refers to the smallest unit constituting the battery device 100. Each battery cell 20 may be a secondary battery or a primary battery, wherein a secondary battery refers to a battery cell 20 that can be continuously used by activating the active material by charging after the battery cell 20 is discharged; the battery cell 20 may be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0061] Please refer to Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of the present application. Figure 4 for Figure 3 The exploded view of the battery cell 20 is shown. The battery cell 20 is the smallest unit that makes up the battery. Figure 3 The battery cell 20 includes an end cover 21, a shell 22, an electrode assembly 23 and other functional components.

[0062] The end cap 21 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the shell 22 to match the shell 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 21 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 21a can be provided on the end cap 21. The electrode terminal 21a can be used to electrically connect with the electrode assembly 23 for outputting or inputting electrical energy of the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism 24 for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this. In some embodiments, an insulating member may be provided inside the end cap 21, and the insulating member may be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0063] The shell 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 23, the electrolyte and other components. The shell 22 and the end cap 21 can be independent components, and an opening can be set on the shell 22, and the internal environment of the battery cell 20 is formed by covering the opening with the end cap 21 at the opening. Without limitation, the end cap 21 and the shell 22 can also be integrated. Specifically, the end cap 21 and the shell 22 can form a common connection surface before other components are put into the shell, and when the interior of the shell 22 needs to be encapsulated, the end cap 21 covers the shell 22. The shell 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 22 can be determined according to the specific shape and size of the electrode assembly 23. The material of the shell 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0064] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 23 may be included in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 23, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 23a. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tab 23a connects the electrode terminals to form a current loop.

[0065] The technical solution provided in the embodiments of the present application is described below with reference to the accompanying drawings.

[0066] Please refer to Figure 2 The embodiment of the first aspect of the present application provides a battery device 100, including a box body 10 and a battery cell 20. The box body 10 includes a box body 101, and the box body 101 includes a surrounding wall 11 and a first cover plate 12. The surrounding wall 11 includes a first direction (such as Figure 2 The fixed section 111 and the expansion section 112 are distributed in the first direction (in the direction indicated by Z in FIG. 1 ), the first direction is perpendicular to the first cover plate 12, the first cover plate 12 is connected to the end of the expansion section 112 away from the fixed section 111, the first cover plate 12 and the surrounding wall 11 together enclose a receiving space, and the expansion section 112 can be expanded along the first direction when the air pressure in the receiving space is greater than a threshold value. Please refer to Figure 5 , Figure 5 It is a schematic diagram of the bottom structure of a battery cell 20 provided in an embodiment of the present application. The battery cell 20 is disposed in the accommodation space. The battery cell 20 has a pressure relief mechanism 24 and the pressure relief mechanism 24 faces the first cover plate 12 .

[0067] The box body 101 is a basic component of the box body 10, and is used to define a storage space for storing the battery cells 20. The box body 101 can be in various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. The surrounding wall 11 is the side wall of the box body 101. The surrounding wall 11 is closed around the first direction and has two opposite ends in the first direction, one of which is connected to the first cover plate 12. The fixed section 111 is the main part of the surrounding wall 11, and is used to provide basic structural support for the box body 101. The size of the fixed section 111 in the first direction remains unchanged, and has good rigidity and mechanical strength. The material of the fixed section 111 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, hard metal or other strong materials. The extended section 112 is an extended part of the surrounding wall 11. The extended section 112 includes a folded state and an unfolded state, please refer to Figure 8 , Figure 8 1 is a partial structural diagram of a battery device 100 provided in an embodiment of the present application, wherein the expansion section 112 of the surrounding wall 11 is in a folded state. In the folded state, the expansion section 112 is close to or close to the fixed section 111. Please refer to Fig. 9 , Fig. 9 The schematic diagram of the partial structure of the battery device 100 provided in an embodiment of the present application, wherein the expansion section 112 of the surrounding wall 11 is in an expanded state, and in the expanded state, the expansion section 112 extends along the first direction toward the direction away from the fixed section 111. It can be understood that after the expansion section 112 is expanded, the size of the surrounding wall 11 along the first direction and the volume of the accommodation space increase, while the structure of the fixed section 111 of the surrounding wall 11 and the position of the battery cell 20 in the box 10 remain unchanged. The expansion section 112 can be made of a high ductility material or a high plasticity material. For example, the expansion section 112 includes a foldable aluminum sheet. The fixed section 111 and the expansion section 112 can be an integral structure or a split structure. When the two are split structures, they can be fixedly connected by bonding, sleeve connection, welding, locking connection, etc. The first cover plate 12 can be a flat plate with a certain thickness. The first cover plate 12 is sealed and connected to the surrounding wall 11 and closes the accommodation space at one end of the surrounding wall 11. Without limitation, the first cover plate 12 can be used as the top plate or bottom plate of the box 10. The first cover plate 12 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, hard metal or other solid materials. The first cover plate 12 and the surrounding wall 11 can be an integral structure or a split structure. When the two are split structures, they can be fixedly connected by bonding, sleeve connection, welding, locking connection, etc.

[0068] It should be noted that, in order to ensure the safety of the battery device 100, the storage space is generally a closed structure. For example, please refer to Figure 2A second cover plate 13 is further provided at one end of the surrounding wall 11 away from the first cover plate 12 , or the end of the surrounding wall 11 away from the first cover plate 12 is directly mounted on the electrical equipment, for example, on the floor structure of the vehicle 1000 .

[0069] Based on the structural design of the surrounding wall 11, the expansion section 112 itself has a folding maintenance force F, which enables the expansion section 112 to maintain in a folded state. The maximum folding maintenance force F that the expansion section 112 can provide is max The threshold is a critical value for maintaining the expansion section 112 in the folded state, and the specific value of the threshold is related to the structure of the expansion section 112, the structure of the first cover plate 12, the assembly method of the battery device 100, and other factors.

[0070] When the battery cell 20 is in normal working condition, the air pressure p in the accommodation space is in a safe range. At this time, the pulling force of the first cover plate 12 on the extension section 112 is less than the maximum folding maintenance force F of the extension section 112. max , so that the extended section 112 is maintained in a folded state. When the battery cell 20 is in an abnormal working condition, the air pressure p in the accommodation space increases and reaches a critical range. At this time, the pulling force of the first cover plate 12 on the extended section 112 is greater than the maximum folding maintenance force F of the extended section 112. max , so that the first cover plate 12 can pull the expansion section 112, so that the expansion section 112 extends along the first direction toward the end away from the fixed section 111. It can be understood that as the expansion section 112 is unfolded, the distance between the battery cell 20 and the first cover plate 12 increases, and a discharge channel is formed between the battery cell 20 and the first cover plate 12. It should be noted that the degree of expansion of the expansion section 112 is positively correlated with the air pressure p in the accommodation space. The pulling force of the first cover plate 12 on the expansion section 112 at least includes the pressure on the first cover plate 12. In some cases, for example, when the battery device 100 is installed at the bottom of the vehicle 1000 and the first cover plate 12 is set away from the bottom, the pulling force of the first cover plate 12 on the expansion section 112 also includes the gravity of the first cover plate 12 itself.

[0071] In the battery device 100 provided in the above embodiment, the surrounding wall 11 of the box body 101 includes a fixed section 111 and an expansion section 112. The expansion section 112 can be expanded along a first direction when the air pressure in the accommodating space is greater than a threshold value. In this way, when the battery cell 20 undergoes thermal runaway and releases uncontrolled spray into the accommodating space, as the air pressure in the accommodating space increases, the first cover plate 12 can move in a direction away from the battery cell 20 and form a discharge channel between the battery cell 20 and the first cover plate 12. Since the height of the discharge channel in the first direction is relatively large, sufficient moving space and a smooth discharge path can be provided for the spray, thereby reducing the risk of the spray impacting the adjacent battery cell 20 and gathering and clogging in the box body 10, thereby improving the reliability and safety of the battery device 100.

[0072] In the battery device 100 provided in the embodiment of the present application, the structure of the expansion section 112 is not unique.

[0073] Optionally, in some embodiments, the expansion section 112 includes a telescopic portion that can move along the first direction. As an example, the expansion section 112 can include multiple sleeves that are nested together and can slide along the first direction, or the expansion section 112 can include multiple folding plate structures.

[0074] Optionally, in some embodiments, the expansion section 112 includes a deformation portion, and the deformation portion can be stretched and deformed along the first direction. As an example, the expansion section 112 is made of an elastic material, and the expansion section 112 can be elastically deformed and expanded.

[0075] In the above embodiment, the expansion section 112 has a reasonable structure, and the box body 10 can achieve space expansion through simple expansion or deformation.

[0076] Please refer to Figure 6 and Figure 7 , Figure 6 is a cross-sectional view of a battery device 100 provided in one embodiment of the present application, Figure 7 A partial structural diagram of a battery device 100 provided in an embodiment of the present application. In some embodiments, the expansion section 112 includes a plurality of folding plates 14, and the plurality of folding plates 14 are bent and connected to form a second direction (such as Figure 7 The fold 15 extends in a direction (indicated by X) and the second direction is perpendicular to the first direction.

[0077] The folding plate 14 is a flat plate with a certain thickness, and the plurality of folding plates 14 can be an integrally formed structure. The bending connection refers to the angle formed between adjacent folding plates 14. The folding line 15 is a linear path between adjacent folding plates 14, and the folding line 15 can define the folding or stretching direction of the folding plate 14. As an example, please refer to Figure 2The box body 10 may be in a rectangular shape, the first direction is a height direction Z of the box body 10 , and the second direction is a width direction Y or a length direction X of the box body 10 .

[0078] It should be noted that the folding maintenance force F of the expansion section 112 can be the deformation stress of the folding plate 14, and the expansion of the expansion section 112 is actually the angle change of the folding plate 14. The folding and unfolding of the folding plate 14 are two relative states. The angle between adjacent folding plates 14 in the folded state is smaller than the angle between adjacent folding plates 14 in the unfolded state. The angle between adjacent folding plates 14 in the folded state has an upper limit and a lower limit, and the lower limit of the angle is 0°. At this time, the folding plates 14 are tightly fitted, and the upper limit of the angle is less than 180°. The specific value depends on the application requirements; the angle between adjacent folding plates 14 in the unfolded state has an upper limit, and the upper limit of the angle is 180°. At this time, the expansion section 112 is fully unfolded.

[0079] Please refer to Figure 8 and Fig. 9 , for example, in a specific embodiment, the expansion section 112 includes a first folding plate 141 and a second folding plate 142, wherein the first folding plate 141 is connected to the fixed section 111, the second folding plate 142 is connected to the first cover plate 12, the first folding plate 141 and the second folding plate 142 are folded toward the inside of the box body 101, and an angle α is formed between the outer walls of the first folding plate 141 and the second folding plate 142, and as the expansion section 112 is unfolded, α increases. Assuming that the plate width of the first folding plate 141 and the second folding plate 142 in the distribution direction is d, the angle between the first folding plate 141 and the second folding plate 142 in the folded state is α1, and the angle between the first folding plate 141 and the second folding plate 142 in the unfolded state is α2, then in the folded state, the height H1 of the expansion section 112 in the first direction is 2d*sin(α1 / 2), and in the unfolded state, the height H2 of the expansion section 112 in the first direction is 2d*sin(α2 / 2).

[0080] The specific number and size of the folding plates 14 depend on application requirements. For example, the expansion section 112 may also include three, four or more folding plates 14 .

[0081] With the above design, the structure of the extension section 112 of the surrounding wall 11 is simple, and the height variation range of the extension section 112 in the folded state and the unfolded state is relatively large, so the extension section 112 has high practicality.

[0082] In some embodiments, the elongation at break X of the folding plate 14 is ≥ 30%, and / or the elastic modulus E of the folding plate 14 is ≤ 100 GPa.

[0083] The elongation at break X reflects the degree to which a material can undergo plastic deformation under tensile force. Materials with high elongation at break can undergo large plastic deformation without breaking when stretched by external force. The elastic modulus E reflects the material's ability to resist elastic deformation. The larger the elastic modulus, the less likely the material is to undergo elastic deformation.

[0084] With the above design, the folding plate 14 has good ductility or plasticity, meeting the design requirements of the expansion section 112 .

[0085] In some embodiments, the material of the folding plate 14 can be any one of polyethylene naphthalate, polyamide fiber, copper, and aluminum.

[0086] Optionally, in a specific embodiment, the folding plate 14 is an aluminum sheet.

[0087] When the folding plate 14 is a metal sheet, the folding maintaining force F may be the deformation stress of the metal sheet. In this design, the folding plate 14 does not need to be restored to the folded state after being unfolded.

[0088] It can be understood that in some cases, the expansion section 112 is made of elastic material, and the expansion section 112 can be elastically deformed and unfolded. When the air pressure in the accommodating space decreases, the expansion section 112 can also return to the folded state.

[0089] Please refer to Figure 2 In some embodiments, the box body 10 further includes a pressure balancing mechanism 102, which is disposed on the surrounding wall 11. The pressure balancing mechanism 102 is configured to open when the expansion section 112 is unfolded and the air pressure in the accommodation space exceeds a safe range, so as to release the pressure in the accommodation space.

[0090] The pressure balance mechanism 102 includes but is not limited to a balance valve and an exhaust valve. After the battery cell 20 has thermal runaway, the pressure relief mechanism 24 opens and releases high-temperature and high-pressure gas into the accommodation space. As the air pressure in the accommodation space increases, the expansion section 112 expands. When the expansion section 112 expands to the limit value and the air pressure in the accommodation space continues to increase until it exceeds the safe range, the pressure balance mechanism 102 opens and releases the gas in the accommodation space to the outside of the box 10. The safe range of the air pressure in the accommodation space is determined according to the design requirements of the battery device 100.

[0091] The pressure balancing mechanism 102 may be disposed on the fixed section 111 of the surrounding wall 11. For example, the surrounding wall 11 includes two first side panels and two second side panels, the two first side panels are disposed oppositely along the length direction X of the box body 101, the two second side panels are disposed oppositely along the width direction Y of the box body 101, and the pressure balancing mechanism 102 is disposed on the fixed section 111 of the first side panels.

[0092] On the one hand, by providing the pressure balancing mechanism 102, the safety of the battery device 100 is further improved. On the other hand, the fixed section 111 of the surrounding wall 11 is the main supporting part of the box body 101, which has high rigidity and mechanical strength and is not easy to deform, so it can provide stable and reliable support for the pressure balancing mechanism 102.

[0093] The pressure balance mechanism 102 may be disposed at any position. In some other embodiments, the pressure balance mechanism 102 may also be disposed on the first cover plate 12. The pressure balance mechanism 102 generally avoids the pressure relief mechanism 24 of the battery cell 20 to prevent the uncontrolled spray generated by the battery cell 20 from directly impacting the pressure balance mechanism 102.

[0094] Please refer to Figure 2 In some embodiments, the box body 101 further includes a support member disposed in the accommodating space, the support member being connected to the fixing section 111 and being used to support the battery cell 20 .

[0095] The support member is fixedly arranged in the accommodation space and is used to carry and fix the battery cell 20. The support member can be a variety of structures, such as a support plate and a support rod. The support member is made of a high-strength, high-temperature-resistant, and corrosion-resistant material, such as aluminum alloy, stainless steel, and other metal materials. The support member can be fixed to the fixed section 111 of the surrounding wall 11 by bonding, clamping, welding, locking, and the like.

[0096] On the one hand, the support member can fix the battery cell 20 at a specific position to prevent the battery cell 20 from moving during use and avoid the battery cell 20 from pressing on the first cover plate 12; on the other hand, the support member is directly connected to the surrounding wall 11, which is conducive to enhancing the structural strength of the box body 10 and reducing the risk of deformation of the box body 10.

[0097] Please refer to Figure 2 , Figure 5 and Figure 6 In some embodiments, the support member is a support plate 16, which is disposed in the accommodation space and opposite to the first cover plate 12. The support plate 16 divides the accommodation space into a first part 17 and a second part 18 distributed along a first direction. The battery cell 20 is accommodated in the first part 17, and a first through hole 161 connecting the first part 17 and the second part 18 is provided on the support plate 16.

[0098] The support plate 16 is a flat plate with a certain thickness. For example, the support plate 16 is provided with first through holes 161 that match the number of battery cells 20 and the position of the pressure relief mechanism 24. The first through holes 161 can have various shapes, such as round holes, square holes or other special-shaped holes.

[0099] There is a gap between the support plate 16 and the first cover plate 12, namely, the second part 18. After the expansion section 112 is unfolded, the space of the second part 18 is increased. When the battery cell 20 has thermal runaway, the spray released by the pressure relief mechanism 24 can enter the second part 18 through the first through hole 161.

[0100] Optionally, the support plate 16 is connected to the junction of the fixed section 111 and the extended section 112 on the surrounding wall 11, so that the support plate 16 and the fixed section 111 of the surrounding wall 11 form a first part 17, and the support plate 16, the first cover plate 12, and the extended section 112 of the surrounding wall 11 form a second part 18.

[0101] With the above design, the support plate 16 has a high structural strength and can provide stable and reliable support for the battery cell 20. At the same time, the support plate 16 divides the accommodating space into a first part 17 and a second part 18, which can isolate the battery cell 20 from liquid or solid spray along a first direction, further reducing the risk of the spray impacting the battery cell 20.

[0102] It can be understood that in some other embodiments, the box body 101 may include structures such as cross beams and longitudinal beams, and the battery cells 20 may be directly fixed to these cross beams or longitudinal beams.

[0103] Please refer to Figure 2 , Figure 5 and Figure 6 In some embodiments, the box body 101 also includes a partition 19, which is vertically arranged on the side of the support plate 16 away from the first cover plate 12, and divides the first part 17 into a third part 171 and a fourth part 172. The battery cell 20 is accommodated in the third part 171, and the first through hole 161 connects the second part 18 and the third part 171.

[0104] The support plate 16 and the partition plate 19 together divide the accommodating space into a second part 18, a third part 171 and a fourth part 172, wherein the third part 171 is used to place the battery cell 20, and the fourth part 172 can be used to form an exhaust channel, or to form an electrical compartment to store functional components.

[0105] With the above design, the support plate 16 and the partition plate 19 can be used to define an independent space within the accommodating space to store the battery cells 20 , further reducing the risk of the spray impacting the battery cells 20 .

[0106] In some embodiments, the support plate 16 is further provided with a second through hole 162 connecting the second portion 18 and the fourth portion 172 .

[0107] One or more second through holes 162 are provided on the partition 19 . The second through holes 162 may have various shapes, for example, circular holes, square holes or other special-shaped holes.

[0108] With the above design, the first through hole 161 and the second through hole 162 are used to connect various parts in the box body 10, so that the pressure of various parts in the box body 10 can be kept consistent, which is conducive to improving the rationality of the actuation of the pressure balance mechanism 102 and further improving the safety of the battery device 100.

[0109] In some embodiments, the box body 10 also includes a pressure balancing mechanism 102, which is disposed on the surrounding wall 11 opposite to the fourth part 172. The pressure balancing mechanism 102 is used to open when the expansion section 112 is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

[0110] The second portion 18 and the fourth portion 172 are connected through the second through hole 162 and together form a discharge channel. The high-temperature and high-pressure gas released by the battery cell 20 can enter the second portion 18 from the third portion 171 through the first through hole 161, and enter the fourth portion 172 from the second portion 18 through the second through hole 162, and finally be discharged from the pressure balance mechanism 102, while the solid particle spray or liquid drop spray can be accumulated in the second portion 18, or enter the fourth portion 172 together with the gaseous spray.

[0111] With the above design, the support plate 16 and the partition plate 19 are used to define an independent discharge channel in the accommodation space, which further reduces the risk of the spray impacting the battery cell 20.

[0112] Please refer to Figure 2 In some embodiments, the box body 101 further includes a second cover plate 13, which is connected to one end of the fixed section 111 away from the expansion section 112, and the first cover plate 12, the second cover plate 13 and the surrounding wall 11 together form a receiving space.

[0113] The second cover plate 13 can be a flat plate with a certain thickness. The second cover plate 13 is sealed and connected to the surrounding wall 11 and closes the accommodation space at one end of the surrounding wall 11. The second cover plate 13 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, hard metal or other solid materials. The second cover plate 13 and the surrounding wall 11 can be an integral structure or a split structure. When the two are split structures, they can be fixedly connected by bonding, sleeve connection, welding, locking connection, etc.

[0114] It can be understood that the second cover plate 13 can be used as the top plate or the bottom plate of the box body 10 .

[0115] On the one hand, the first cover plate 12 and the second cover plate 13 jointly support the surrounding wall 11, which can improve the structural strength of the box body 10. On the other hand, the first cover plate 12, the second cover plate 13 and the surrounding wall 11 jointly form a closed accommodating space, and the box body 10 has good sealing performance, which can effectively prevent moisture, dust or other pollutants from entering the interior of the box body 10.

[0116] In one embodiment provided by the present application, a battery device 100 includes a box body 10 and a battery cell 20, and the box body 10 includes a box body 101 and a pressure balancing mechanism 102, wherein the battery cell 20 is arranged in the accommodation space surrounded by the box body 101, and the pressure balancing mechanism 102 is arranged on the surrounding wall 11 of the box body 101. The surrounding wall 11 of the box body 101 includes a fixed section 111 and an expansion section 112, wherein the expansion section 112 includes a plurality of folding plates 14 connected by bending, and the plurality of folding plates 14 can be unfolded toward a side away from the fixed section 111 when the air pressure in the accommodation space is greater than a threshold value, so as to increase the volume of the accommodation space. A support plate 16 and a partition 19 are also arranged in the box body 101, and the support plate 16 is mainly used to carry and fix the battery cell 20. At the same time, the support plate 16 and the partition 19 separate an independent discharge channel in the accommodation space, and part of the discharge channel is composed of the expansion section 112 of the surrounding wall 11, and the space of the discharge channel is increased when the expansion section 112 is unfolded. The battery device 100 provided by the above embodiment has the following advantages: 1. When the battery device 100 is in normal working condition, the expansion section 112 is in a folded state, and the overall size of the battery device 100 is small, so that it has a higher volume density ratio; 2. When the battery device 100 is in abnormal working condition, the expansion section 112 is unfolded, providing sufficient moving space and a smooth discharge path for the spray generated by the battery cell 20, thereby reducing the risk of the spray impacting the adjacent battery cell 20 and gathering and clogging in the box body 10, thereby improving the reliability and safety of the battery device 100; 3. By using the support plate 16 and the partition plate 19 to separate an independent discharge channel in the accommodating space of the box body 10, the battery cell 20 can be isolated from the liquid or solid spray, further reducing the risk of the spray impacting the battery cell 20, and improving the reliability and safety of the battery device 100.

[0117] An embodiment of a second aspect of the present application provides a box 10 , which is used in a battery device 100 , wherein the battery device 100 includes a battery cell 20 .

[0118] Please refer to Figure 2 and Figure 6The box body 10 provided in the embodiment of the present application includes a box body 101, and the box body 101 includes a surrounding wall 11 and a first cover plate 12. The surrounding wall 11 includes a fixed section 111 and an extended section 112 distributed along a first direction. The first direction is perpendicular to the first cover plate 12. The first cover plate 12 is connected to an end of the extended section 112 away from the fixed section 111. The first cover plate 12 and the surrounding wall 11 together form a storage space for placing a battery cell 20. The extended section 112 can be expanded along the first direction when the air pressure in the storage space is greater than a threshold.

[0119] In the box body 10 provided in the above embodiment, the surrounding wall 11 of the box body 101 includes a fixed section 111 and an expansion section 112. The expansion section 112 can be expanded along a first direction when the air pressure in the accommodating space is greater than a threshold value. In this way, when the battery cell 20 undergoes thermal runaway and releases uncontrolled spray into the accommodating space, as the air pressure in the accommodating space increases, the first cover plate 12 can move in a direction away from the battery cell 20 and form a discharge channel between the battery cell 20 and the first cover plate 12. Since the height of the discharge channel in the first direction is relatively large, sufficient moving space and a smooth discharge path are provided for the spray, thereby reducing the risk of the spray impacting the adjacent battery cell 20 and gathering and clogging in the box body 10. The box body 10 is used to store the battery cells 20 with higher reliability and safety.

[0120] In the box body 10 provided in the embodiment of the present application, the structure of the expansion section 112 is not unique.

[0121] Optionally, in some embodiments, the expansion section 112 includes a telescopic portion that can move along the first direction. As an example, the expansion section 112 can include multiple sleeves that are nested together and can slide along the first direction, or the expansion section 112 can include multiple folding plate structures.

[0122] Optionally, in some embodiments, the expansion section 112 includes a deformation portion, and the deformation portion can be stretched and deformed along the first direction. As an example, the expansion section 112 is made of an elastic material, and the expansion section 112 can be elastically deformed and expanded.

[0123] In the above embodiment, the expansion section 112 has a reasonable structure, and the box body 10 can achieve space expansion through simple expansion or deformation.

[0124] Please refer to Figure 2 and Figure 7 In some embodiments, the expansion section 112 includes a plurality of folding plates 14, which are bent and connected to form folds 15 extending along a second direction at the connection points, and the second direction is perpendicular to the first direction.

[0125] With the above design, the structure of the extension section 112 of the surrounding wall 11 is simple, and the height variation range of the extension section 112 in the folded state and the unfolded state is relatively large, so the extension section 112 has high practicality.

[0126] In some embodiments, the elongation at break X of the folding plate 14 is ≥ 30%, and / or the elastic modulus E of the folding plate 14 is ≤ 100 GPa.

[0127] With the above design, the folding plate 14 has good ductility or plasticity, meeting the design requirements of the expansion section 112 .

[0128] In some embodiments, the material of the folding plate 14 can be any one of polyethylene naphthalate, polyamide fiber, copper, and aluminum.

[0129] In some embodiments, the box 10 further includes a pressure balancing mechanism 102 , which is disposed on the surrounding wall 11 , and is used to open when the expansion section 112 is unfolded and the air pressure in the accommodation space exceeds a safe range to release the pressure in the accommodation space.

[0130] On the one hand, by providing the pressure balancing mechanism 102, the safety of the box body 10 and the battery device 100 using the box body 10 is further improved. On the other hand, the fixed section 111 of the surrounding wall 11 is the main supporting part of the box body 101, which has high rigidity and mechanical strength and is not easy to deform, so it can provide stable and reliable support for the pressure balancing mechanism 102.

[0131] The pressure balance mechanism 102 may be disposed at any position. In some other embodiments, the pressure balance mechanism 102 may also be disposed on the first cover plate 12. The pressure balance mechanism 102 generally avoids the pressure relief mechanism 24 of the battery cell 20 to prevent the uncontrolled spray generated by the battery cell 20 from directly impacting the pressure balance mechanism 102.

[0132] Please refer to Figure 2 and Figure 6 In some embodiments, the box body 101 further includes a support plate 16 disposed in the accommodation space, the support plate 16 being connected to the fixing section 111 and used to carry the battery cell 20. The support plate 16 is disposed opposite to the first cover plate 12, and divides the accommodation space into a first portion 17 and a second portion 18 distributed along a first direction, the battery cell 20 is accommodated in the first portion 17, and a first through hole 161 connecting the first portion 17 and the second portion 18 is provided on the support plate 16.

[0133] With the above design, the support plate 16 has a high structural strength and can provide stable and reliable support for the battery cell 20. At the same time, the support plate 16 can isolate the battery cell 20 from liquid or solid spray, thereby further reducing the risk of the spray directly impacting the battery cell 20.

[0134] Please refer to Figure 2 and Figure 6 In some embodiments, the box body 101 also includes a partition 19, which is vertically arranged on the side of the support plate 16 away from the first cover plate 12, and divides the first part 17 into a third part 171 and a fourth part 172. The battery cell 20 is accommodated in the third part 171, and the first through hole 161 connects the second part 18 and the third part 171. The support plate 16 is also provided with a second through hole 162 connecting the second part 18 and the fourth part 172.

[0135] With the above design, an independent discharge channel can be defined in the accommodation space by using the support plate 16 and the partition plate 19 , further reducing the risk of the spray impacting the battery cell 20 .

[0136] Please refer to Figure 2 In some embodiments, the box body 101 further includes a second cover plate 13, which is connected to one end of the fixed section 111 away from the expansion section 112, and the first cover plate 12, the second cover plate 13 and the surrounding wall 11 together form a receiving space.

[0137] On the one hand, the first cover plate 12 and the second cover plate 13 jointly support the surrounding wall 11, which can improve the structural strength of the box body 10. On the other hand, the first cover plate 12, the second cover plate 13 and the surrounding wall 11 jointly form a closed accommodating space, and the box body 10 has good sealing performance, which can effectively prevent moisture, dust or other pollutants from entering the interior of the box body 10.

[0138] In summary, the box body 10 provided in the embodiment of the present application improves the structure of the surrounding wall 11 in the box body 101 and designs a foldable or unfoldable extension section 112 on the surrounding wall 11, thereby effectively improving the reliability and safety of the box body 10.

[0139] An embodiment of the third aspect of the present application provides an electrical device, including the battery device 100 in each embodiment of the first aspect.

[0140] The electric device provided in the embodiment of the present application improves the reliability and safety of the electric device by adopting the battery device 100 in the first aspect.

[0141] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A battery device, characterized in that: include: A box body, comprising a box body, the box body comprising a surrounding wall and a first cover plate, the surrounding wall comprising a fixed section and an extended section distributed along a first direction, the first direction being perpendicular to the first cover plate, the first cover plate being connected to an end of the extended section away from the fixed section, the first cover plate and the surrounding wall together enclosing a containing space, the extended section being able to be expanded along the first direction when the air pressure in the containing space is greater than a threshold value; A battery cell is disposed in the accommodation space, wherein the battery cell has a pressure relief mechanism and the pressure relief mechanism faces the first cover plate.

2. The battery device according to claim 1, characterized in that The expansion section includes a telescopic portion, which is capable of moving along the first direction, and / or the expansion section includes a deformation portion, which is capable of stretching and deforming along the first direction.

3. The battery device according to claim 1, characterized in that: The expansion section includes a plurality of folding plates, which are bent and connected to form folds extending along a second direction at the connection points, and the second direction is perpendicular to the first direction.

4. The battery device according to claim 3, characterized in that: The elongation at break X of the folding plate is ≥30%, and / or the elastic modulus E of the folding plate is ≤100 GPa.

5. The battery device according to claim 1, wherein: The box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall or the first cover plate. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

6. The battery device according to claim 1, wherein: The box body also includes a support plate, which is arranged in the accommodating space and opposite to the first cover plate. The support plate divides the accommodating space into a first part and a second part distributed along the first direction. The battery cell is accommodated in the first part. A first through hole connecting the first part and the second part is provided on the support plate.

7. The battery device according to claim 6, characterized in that: The box body also includes a partition, which is vertically arranged on a side of the support plate away from the first cover plate and divides the first part into a third part and a fourth part. The battery cell is accommodated in the third part, and the first through hole connects the second part and the third part.

8. The battery device according to claim 7, characterized in that: The support plate is also provided with a second through hole connecting the second part and the fourth part.

9. The battery device according to claim 8, characterized in that: The box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall opposite to the fourth part. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

10. The battery device according to any one of claims 1 to 9, characterized in that: The box body further includes a second cover plate, the second cover plate is connected to an end of the fixed section away from the extended section, and the first cover plate, the second cover plate and the surrounding wall together enclose the accommodating space.

11. A box, characterized in that: Used in a battery device, the battery device includes a battery cell, the box body includes a box body, the box body includes a surrounding wall and a first cover plate, the surrounding wall includes a fixed section and an extended section distributed along a first direction, the first direction is perpendicular to the first cover plate, the first cover plate is connected to an end of the extended section away from the fixed section, the first cover plate and the surrounding wall together form a storage space for placing the battery cell, and the extended section can be expanded along the first direction when the air pressure in the storage space is greater than a threshold value.

12. The box body according to claim 11, characterized in that: The expansion section includes a telescopic portion, which is capable of moving along the first direction, and / or the expansion section includes a deformation portion, which is capable of stretching and deforming along the first direction.

13. The box body according to claim 11, characterized in that: The expansion section includes a plurality of folding plates, which are bent and connected to form folds extending along a second direction at the connection points, and the second direction is perpendicular to the first direction.

14. The box body according to claim 13, characterized in that: The elongation at break X of the folding plate is ≥30%, and / or the elastic modulus E of the folding plate is ≤100 GPa.

15. The box body according to claim 11, characterized in that: The box body also includes a pressure balancing mechanism, which is arranged on the surrounding wall or the first cover plate. The pressure balancing mechanism is used to open when the expansion section is unfolded and the air pressure in the accommodating space exceeds a safe range to release the pressure in the accommodating space.

16. The box according to any one of claims 11 to 15, characterized in that: The box body further includes a second cover plate, the second cover plate is connected to an end of the fixed section away from the extended section, and the first cover plate, the second cover plate and the surrounding wall together enclose the accommodating space.

17. An electrical equipment, characterized in that: Comprising the battery device according to any one of claims 1-10.

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