Battery device and electric device

Abstract

The embodiment of the utility model provides a battery device and a power utilization device, and relates to a battery device, the battery device comprises a box body and a battery monomer, the box body comprises a first wall; the battery monomer assembly is at least partially accommodated in the box body, and the battery monomer assembly comprises a plurality of battery monomers; the first wall comprises a first plate body and a second plate body which are arranged in a split manner and connected with each other, the first plate body is arranged between the battery monomer assembly and the second plate body along a first direction, and the first direction is the thickness direction of the first wall; the second plate body is provided with a groove sunken in the direction away from the first plate body and a convex part protruding towards the first plate body, the first plate body covers the groove to form a cavity, and the first plate body is connected with the convex part. According to the battery device provided by the embodiment of the invention, the first plate body and / or the second plate body which are / is arranged in a split manner can be directly treated when the plate body on one side of the forming cavity is retreated, so that the influence of subsequent retreatment steps on the formed cavity can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery device and a power utilization device. BACKGROUND

[0002] Energy saving and emission reduction is the key to the sustainable development of the automobile industry. In this case, electric vehicles have become an important part of the sustainable development of the automobile industry due to their energy saving and environmental protection advantages. For electric vehicles, battery technology is an important factor for their development.

[0003] In the development of battery technology, the economy of the battery is a problem that cannot be ignored. If the economy of the battery is poor, the battery will be difficult to popularize. Therefore, how to improve the economy of the battery is a technical problem that needs to be considered for a long time in battery technology. CONTENT OF THE INVENTION

[0004] The present application provides a battery device and a power utilization device, which can improve the economy of the battery.

[0005] The present application is realized by the following technical solutions:

[0006] In a first aspect, the present application provides a battery device, comprising a box body and a battery monomer, the box body comprising a first wall; a battery monomer assembly is at least partially accommodated in the box body, the battery monomer assembly comprising a plurality of battery monomers; the first wall comprises a first plate body and a second plate body which are separately arranged and connected to each other, along a first direction, the first plate body is arranged between the battery monomer assembly and the second plate body, the first direction being the thickness direction of the first wall; the second plate body is provided with a groove recessed in a direction away from the first plate body and a protrusion protruding in a direction towards the first plate body, the first plate body covers the groove to form a cavity, and the first plate body is connected to the protrusion.

[0007] In the above embodiment, the cavity is formed by the separately arranged first plate body and the second plate body, when the side plate body of the formed cavity is reprocessed, the separately arranged first plate body and / or the second plate body can be directly processed, thereby reducing the influence of the subsequent reprocessing step on the already formed cavity.

[0008] In some embodiments, the battery cell is provided with a pressure relief mechanism on the side facing the first wall, the first plate body is provided with a first through hole, the first through hole is arranged opposite to the pressure relief mechanism, and the first through hole is in communication with the cavity. The formed cavity can be used as a collection cavity for collecting emissions from the battery cell provided with the pressure relief mechanism when the pressure relief mechanism is actuated. The first plate body and the second plate body that enclose the collection cavity are separately arranged, so that the process of forming the first through hole on the first plate body can be carried out before the first plate body and the second plate body enclose the collection cavity, and thus the process of forming the first through hole can hardly affect the collection cavity and the other side cavity wall of the collection cavity which is not provided with the first through hole. This can effectively reduce the difficulty of forming the first through hole on the cavity wall of the collection cavity, thereby achieving the purposes of improving the processing efficiency and reducing the processing cost, and ultimately obtaining a battery device with higher economic efficiency

[0009] In some embodiments, the second plate body is provided with a second through hole in communication with the cavity. The second through hole can guide the high-temperature substances in the cavity to be discharged, so as to reduce the residence time of the high-temperature substances in the battery device and thus reduce the influence of the high-temperature substances on the battery device.

[0010] In some embodiments, the second through hole is arranged on the bottom wall of the groove, and the second through hole does not overlap with the first through hole along the first direction. The high-temperature substances first flow into the cavity through the first through hole, and then flow in the cavity and are discharged to the side of the first wall away from the battery cell assembly through the second through hole, so as to reduce the influence of the high-temperature substances on the battery device.

[0011] In some embodiments, a plurality of grooves are arranged, the grooves extend along the second direction, the plurality of grooves are arranged at intervals along the third direction, the second through hole is arranged at at least one end of the grooves along the second direction, and the first direction, the second direction and the third direction are perpendicular to each other. The high-temperature substances are discharged from the second through hole when flowing through the edge of the cavity during the flowing process in the cavity, so that the high-temperature substances are difficult to flow to the side wall of the box, thereby reducing the influence of the high-temperature substances on the whole battery device.

[0012] In some embodiments, the depth of the groove along the first direction is 3-6 mm. Through this arrangement, the height of the pressure relief exhaust channel can be reduced, thereby reducing the overall thickness of the first wall and releasing the space of the battery device in the first direction.

[0013] In some embodiments, the first wall is used to carry the battery cell assembly, and the part of the first plate body connected to the battery cell assembly is a planar structure. This can reduce the abnormality of the locally formed first through hole structure caused by the local inclination of the first plate body, and can reduce the occurrence of the situation that the explosion relief function of the battery device is difficult to meet.

[0014] In some embodiments, the second plate body comprises a first connecting layer and a first reinforcing layer, and the first connecting layer is located between the first reinforcing layer and the first plate body in the first direction and connected to the first plate body. The first reinforcing layer is arranged on the second plate body to strengthen the overall strength of the first wall. In some application scenarios, when the battery device is impacted or scratched by a foreign object, the foreign object will first contact the first reinforcing layer, which has high strength and can reduce damage to other components caused by the foreign object, thereby reducing the impact on the battery device when it is impacted or scratched and improving the reliability of the battery device.

[0015] In some embodiments, the base material of the first connecting layer is aluminum. Aluminum has good corrosion resistance. In some application scenarios, the cavity can contain a cooling medium, and the aluminum layer can reduce the corrosion of the cooling medium to the first wall, thereby improving the service life of the box.

[0016] In some embodiments, the base material of the first reinforcing layer is steel. When the base material of the first reinforcing layer is steel, it can not only improve the strength of the first wall but also improve the overall heat resistance of the first wall, further improving the service reliability of the battery device. Moreover, when the base material of the first reinforcing layer is steel, the heat resistance and strength of steel can support reducing the size of the cavity in the first direction, thereby reducing the space occupied by the box in the first direction.

[0017] In some embodiments, the thickness of the first reinforcing layer is 0.2mm-0.9mm, and / or the thickness of the first connecting layer is 0.1mm-0.8mm. This setting can balance the corrosion resistance, strength, and manufacturing cost of the second plate body.

[0018] In some embodiments, the second plate body further comprises a first intermediate layer, and the first intermediate layer is located between the first connecting layer and the first reinforcing layer in the first direction and connected to the first connecting layer and the first reinforcing layer, respectively. The first intermediate layer can improve the connectivity of the first connecting layer and the first reinforcing layer, effectively reducing the risk of delamination of the first connecting layer and the first reinforcing layer when the first wall is subjected to high-temperature impact.

[0019] In some embodiments, the base material of the first intermediate layer is nickel. Nickel has good stability and can reduce the mutual influence of the first connecting layer and the first reinforcing layer when they are subjected to thermal impact.

[0020] In some embodiments, the thickness of the first intermediate layer is 5μm-10μm. When the thickness in the above embodiments is used, the first connecting layer and the first reinforcing layer can be effectively separated, and the manufacturing cost of the second plate body can also be effectively considered.

[0021] In some embodiments, the second plate body has a thickness of 1mm-2mm. When the thickness is adopted, the strength of the first wall can meet certain requirements while the influence on the space occupation of the first wall in the first direction is as low as possible.

[0022] In some embodiments, the first plate body is made of aluminum and is welded with the first connecting layer. On the one hand, the first plate body made of aluminum can reduce the influence of the cooling medium on the first wall; on the other hand, the first plate body and the first connecting layer are both made of aluminum, which facilitates the welding of the two and thus achieves better connectivity.

[0023] In some embodiments, the first plate body includes a second connecting layer and a second reinforcing layer, the second connecting layer is arranged between the second reinforcing layer and the first connecting layer, and the second connecting layer is connected with the first connecting layer. The connection of the second connecting layer with the first connecting layer and the arrangement of the second reinforcing layer can further improve the overall strength of the first wall and better protect the battery monomer assembly.

[0024] In some embodiments, the second connecting layer is made of aluminum and is welded with the first connecting layer. The second connecting layer made of aluminum facilitates the welding with the first connecting layer.

[0025] In some embodiments, the second reinforcing layer is made of steel. When the base material is made of steel, the overall strength of the first wall can be improved, and the heat resistance of the first wall as a whole can be improved, further improving the use reliability of the battery device. Moreover, when the base material of the second reinforcing layer is made of steel, the overall strength of the first wall can also be improved.

[0026] In some embodiments, the second reinforcing layer has a thickness of 0.2mm-0.9mm, and / or the second connecting layer has a thickness of 0.1mm-0.8mm. This setting can balance the corrosion resistance, strength, and manufacturing cost of the first plate body

[0027] In some embodiments, the first plate body further includes a second intermediate layer, which is located between the second connecting layer and the second reinforcing layer in the first direction, and is connected with the second connecting layer and the second reinforcing layer respectively. The arrangement of the second intermediate layer can improve the connectivity of the second connecting layer and the second reinforcing layer, and effectively reduce the risk of delamination of the second reinforcing layer and the second connecting layer when the first wall is subjected to high-temperature impact.

[0028] In some embodiments, the second intermediate layer is made of nickel. Nickel has good stability and can reduce the mutual influence of the second connecting layer and the second reinforcing layer when they are subjected to thermal impact.

[0029] In some embodiments, the second intermediate layer has a thickness of 5-10 μm. When the thickness in the above embodiments is adopted, effective barriers can be formed for the second connecting layer and the second reinforcing layer, and the manufacturing cost of the first plate body can also be effectively considered.

[0030] In some embodiments, the first plate body has a thickness of 0.5-2 mm. When the thickness is adopted, the strength of the first wall can meet certain requirements, and the forming of the first through hole is also facilitated.

[0031] In a second aspect, the embodiments of the present application provide a battery device.

[0032] Additional aspects and advantages of the present application will be given in part in the following description, become apparent from the following description, or be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0034] Figure 1 Structure diagram of a vehicle of some embodiments of the present application;

[0035] Figure 2 Exploded structure diagram of a battery device of some embodiments of the present application;

[0036] Figure 3 Structure diagram of a battery device of some embodiments of the present application;

[0037] Figure 4 Top view of a first wall of some embodiments of the present application;

[0038] Figure 5 Partial structure diagram of a first wall of some embodiments of the present application;

[0039] Figure 6 Partial structure diagram of a first wall of some embodiments of the present application; Figure 5 Partial enlarged view at A;

[0040] Figure 7 Sectional view of a first wall of some embodiments of the present application;

[0041] Figure 8 Sectional view of a first wall of some embodiments of the present application; Figure 7 Partial enlarged view at B;

[0042] Figure 9 A schematic view of a partial structure of a first wall of another embodiment of the present application;

[0043] Icon:

[0044] 1000, vehicle; 100, battery device; 200, controller; 300, motor; 10, box body; 11, first sub-box body; 12, second sub-box body; 20, battery cell; 201, pressure relief mechanism; 101, first wall; 1011, first plate body; 10111, first through hole; 10112, second connecting layer; 10113, second reinforcing layer; 10114, second intermediate layer; 1012, second plate body; 10121, groove; 10122, convex part; 10123, first connecting layer; 10124, first reinforcing layer; 10125, first intermediate layer; 10126, second through hole; 1013, cavity;

[0045] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0046] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0047] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms “include” and “have” and any variations thereof in the specification of the present application and the claims and the above description of drawings are intended to cover not exclusive inclusion. The terms “first”, “second” and the like in the specification and claims of the present application and the above description of drawings are used to distinguish different objects, rather than to describe a particular order or primary and secondary relationship.

[0048] In the present application, the phrase “embodiment” means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase at various places in the specification does not necessarily mean the same embodiment, nor is it an independent or alternative embodiment to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in the present application can be combined with other embodiments.

[0049] In the description of the present application, it needs to be explained that, unless explicitly specified and limited, the terms "mount", "connect", "connection", "attach" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0050] "Multiple" appearing in the present application refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0051] The battery device mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells connected in series, parallel or mixed connection by busbars.

[0052] In some embodiments, the battery cell assembly is usually formed by arranging a plurality of battery cells; as an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0053] In some embodiments, the battery device can be a battery pack, which includes a box and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the box.

[0054] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the box by fixing the battery module in the box.

[0055] As an example, the battery cell assembly can also be accommodated in the box by directly fixing a plurality of battery cells in the box.

[0056] As an example, the box can include a first sub-box and a second sub-box. The first sub-box and the second sub-box are buckled so that a closed space is formed inside the box to accommodate the battery cell assembly. Here, closed means covered or closed, which can be sealed or unsealed. The first sub-box can be a top cover or a bottom plate.

[0057] As an example, the box can include a top cover, a frame and a bottom plate. The top cover and the bottom plate are connected with the frame respectively, so that a closed space is formed inside the box to accommodate the battery cell assembly.

[0058] As an example, the box can be part of a chassis structure of a vehicle. For example, the top cover of the box can be at least part of a floor panel of the vehicle, or the frame of the box can be at least part of a cross beam and a longitudinal beam of the vehicle.

[0059] In some embodiments, the battery device refers to an energy storage device, and the energy storage device includes a box, at least one side of the box being provided with a door. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0060] In the embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0061] The battery cell can be, but is not limited to, 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-acid battery, etc.

[0062] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the battery cell, active ions (such as lithium ions) are embedded and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can reduce the short circuit between the positive electrode and the negative electrode, and at the same time allow the active ions to pass through.

[0063] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material arranged on at least one surface of the positive electrode current collector.

[0064] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction of itself, and the positive electrode active material is arranged on any one or both of the two opposite surfaces of the positive electrode current collector.

[0065] As an example, the positive electrode current collector can adopt a metal foil or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, titanium, etc. with silver plating treatment on the surface can be used. The composite current collector can include a high polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a high polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0066] As an example, the positive electrode active material can include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials of batteries can also be used.

[0067] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0068] As an example, the negative electrode current collector can employ a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver plating surface treatment, stainless steel with a silver plating surface treatment, copper, aluminum, nickel, a carbon electrode, carbon, titanium, or the like can be employed.

[0069] In some embodiments, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is disposed on either one or both of the two opposite surfaces of the negative electrode current collector.

[0070] As an example, the negative electrode active material can employ a negative electrode active material for a battery known in the art. As an example, the negative electrode active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, lithium titanate, and the like. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative electrode active material for a battery can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0071] In some embodiments, the separator is a separator film. The present application does not particularly limit the type of the separator film, and any known porous structure separator film having good chemical reliability and mechanical reliability can be used.

[0072] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separator film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separator film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separator can be a separate member located between the positive electrode and the negative electrode, or can be attached to the surface of the positive electrode or the negative electrode.

[0073] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode and the negative electrode, and functions to transport ions and separate the positive electrode and the negative electrode.

[0074] In some embodiments, the electrode assembly is a jelly-roll structure. The positive electrode sheet and the negative electrode sheet are wound to form the jelly-roll structure.

[0075] In some embodiments, the electrode assembly is a stack structure.

[0076] In some embodiments, the battery cell can include a housing. The housing is used to encapsulate components such as the electrode assembly and electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0077] In some embodiments, the housing includes an end cap and a shell body, the shell body is provided with an opening, and the end cap closes the opening to form a sealed space for accommodating the electrode assembly and electrolyte, etc. The shell body can be provided with one or more openings. The end cap can also be provided with one or more openings.

[0078] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal can be directly connected to the tab or indirectly connected to the tab through an adapter. The electrode terminal can be provided on the end cap or on the shell body.

[0079] In some embodiments, an explosion-proof valve is provided on the housing. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0080] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, the housing can protect the electrode assembly and reduce electrolyte leakage, etc. When the housing is a non-sealed structure, the housing can protect the electrode assembly, and a sealing bag can be further included between the housing and the electrode assembly, which is used to encapsulate the electrode assembly and electrolyte, etc. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film.

[0081] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or other shaped battery cells, the prismatic battery cell includes a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, etc., and the present application is not particularly limited.

[0082] The cavity provided on the box body of the battery device can be used to assist in achieving the explosion-proof pressure relief function of the battery device. The current way of providing the cavity includes extruding the inside of one side plate of the box body to form the cavity, and the side plate of the formed cavity is an integral whole. However, if the side plate needs to be processed again in the subsequent process, the processing technology can affect the already formed cavity.

[0083] Some embodiments of the present application provide a battery device, comprising a box body, the box body comprising a first wall, the first wall comprising a first plate body and a second plate body arranged separately and connected to each other, and a cavity formed between the first plate body and the second plate body. The battery device provided by the present application can directly process the first plate body and / or the second plate body arranged separately when reprocessing the side plate body of the formed cavity, thereby reducing the influence of the subsequent reprocessing step on the already formed cavity.

[0084] The battery device disclosed in the embodiments of the present application can be used in electric equipment such as vehicles, ships or aircraft, but is not limited thereto. The power supply system of the electric equipment can be composed of the battery device disclosed in the present application.

[0085] The technical solutions described in the embodiments of the present application are applicable to various electric equipment using battery monomers and battery devices, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, such as aircraft, rockets, space shuttles and spacecraft.

[0086] The following embodiments are described for convenience with a vehicle as an example of electric equipment of an embodiment of the present application.

[0087] Please refer to Figure 1 , Figure 1 The structural schematic diagram of the vehicle 1000 provided by some embodiments of the present application is shown. The vehicle 1000 can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile. The vehicle 1000 is internally provided with a battery device 100, which can be arranged at the bottom, the head or the tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000, for example, the battery device 100 can be used as an operating power source of the vehicle 1000, which is used for the circuit system of the vehicle 1000, such as the working power demand during starting, navigation and running of the vehicle 1000.

[0088] The vehicle 1000 can further comprise a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to supply power to the motor 300, such as the working power demand during starting, navigation and running of the vehicle 1000.

[0089] In some embodiments of the present application, the battery device 100 can not only be used as an operating power source of the vehicle 1000, but also be used as a driving power source of the vehicle 1000, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1000.

[0090] Please refer to Figure 2 , Figure 2A structural exploded view of a battery device 100 is provided for some embodiments of the present application. The battery device 100 includes a box 10 and a battery cell 20, the battery cell 20 is accommodated in the box 10. The box 10 is used to provide an accommodation space for the battery cell 20, and the box 10 can adopt various structures. In some embodiments, the box 10 can include a first sub-box 11 and a second sub-box 12, the first sub-box 11 and the second sub-box 12 are mutually covered, and the first sub-box 11 and the second sub-box 12 jointly define an accommodation space for accommodating the battery cell 20. The second sub-box 12 can be a hollow structure with one end open, and the first sub-box 11 can be a plate structure, the first sub-box 11 covers the open side of the second sub-box 12, so that the first sub-box 11 and the second sub-box 12 jointly define the accommodation space; the first sub-box 11 and the second sub-box 12 can also be hollow structures with one side open, and the open side of the first sub-box 11 covers the open side of the second sub-box 12.

[0091] In the battery device 100, the battery cell 20 can be multiple, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed connection. The mixed connection means that there are both series connection and parallel connection among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed connection, and then the whole of the multiple battery cells 20 is accommodated in the box 10; of course, the battery device 100 can also be that the multiple battery cells 20 are first connected in series, in parallel, or in a mixed connection to form a battery module, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and are accommodated in the box 10. The battery device 100 can also include other structures, for example, the battery device 100 can also include a current collecting component for realizing the electrical connection between the multiple battery cells 20.

[0092] Some embodiments of the present application provide a battery device, please refer to Figures 3 to 6 , Figure 3 A structural view of the battery device of some embodiments of the present application, Figure 4 A top view of the first wall 101 of some embodiments of the present application, Figure 5 A partial structural view of the first wall 101 of some embodiments of the present application, Figure 6 A Figure 5 A partial enlarged view at A. Specifically, the battery device 100 includes a box 10 and a battery cell assembly, the box 10 includes a first wall 101, the battery cell assembly is at least partially accommodated in the box 10, and the battery cell assembly includes multiple battery cells 20. Please continue to refer to Figure 7 and Figure 8 , Figure 7 A sectional view of the first wall 101 of some embodiments of the present application, Figure 8 A Figure 7In the enlarged view at point B, the first wall 101 includes a first plate 1011 and a second plate 1012, which are separately disposed. The first plate 1011 and the second plate 1012 are connected to each other. Along a first direction, the first plate 1011 is disposed between the battery cell assembly and the second plate 1012. The second plate 1012 is provided with a groove 10121 recessed in a direction away from the first plate 1011 and a protrusion 10122 protruding in a direction towards the first plate. The first plate 1011 covers the groove 10121 to form a cavity 1013, and the first plate 1011 is connected to the protrusion 10122.

[0093] The first direction is the thickness direction of the first wall 101. In the above embodiment, the cavity 1013 is formed by the separate first plate 1011 and the second plate 1012. When reprocessing one side of the plate of the cavity 1013, the separate first plate 1011 and / or the second plate 1012 can be processed directly, thereby reducing the impact of subsequent reprocessing steps on the already formed cavity 1013.

[0094] In some embodiments, a pressure relief mechanism 201 is provided on the side of the battery cell 20 facing the first wall 101, and a first through hole 10111 is provided on the first plate 10111. The first through hole 10111 is disposed opposite to the pressure relief mechanism 201 and communicates with the cavity 1013.

[0095] In the above embodiments, the first through-hole 10111 may include multiple through-holes, each of which is disposed opposite to a different pressure relief mechanism 201. The first through-hole 10111 being disposed opposite to the pressure relief mechanism 201 means that, on a projection plane perpendicular to the first direction, the projection of the first through-hole 10111 at least partially overlaps with the projection of the pressure relief mechanism 201. The formed cavity 1013 can serve as a collection cavity, used to collect emissions from the battery cell 20 equipped with the pressure relief mechanism 201 when the pressure relief mechanism 201 is braked. The collection cavity, used to collect emissions, can be sealed or unsealed. In some embodiments, the collection cavity may contain air or other gases. The collection cavity has no electrical connection to the voltage output; corresponding to a "high-pressure cavity," the collection cavity can also be called a "low-pressure cavity." Optionally, or additionally, the collection cavity may also contain a liquid, such as a cooling medium, or a component for containing the liquid may be provided to further cool the emissions entering the collection cavity. Further optionally, the gas or liquid in the collection cavity is circulated.

[0096] At present, the battery device usually has a collecting cavity on the box body to assist in achieving the explosion-proof pressure relief function of the battery device. The current method includes extruding the inside of one side plate of the box body to form a collecting cavity, and then forming a plurality of through holes in the cavity wall on one side of the collecting cavity to communicate with the collecting cavity, so as to assist in achieving the explosion-proof pressure relief function of the battery device. In view of the yield of the box body, as little pressure as possible is required to be applied to the collecting cavity during the forming of the through holes in the cavity wall of the collecting cavity, and as little impact as possible is required to be caused to the other cavity wall of the collecting cavity which is not provided with the through holes. Based on the above considerations, the forming of the through holes on the collecting cavity is difficult.

[0097] In the above embodiment, the first plate body 1011 and the second plate body 1012 which enclose the collecting cavity are separately provided, so that the process of forming the first through hole 10111 on the first plate body 1011 is performed before the first plate body 1011 and the second plate body 1012 enclose the collecting cavity, and thus it is difficult to affect the collecting cavity and the other cavity wall of the collecting cavity which is not provided with the first through hole 10111 during the forming of the first through hole 10111. This can effectively reduce the difficulty of forming the first through hole 10111 on the cavity wall of the collecting cavity, thereby achieving the purpose of improving the processing efficiency and reducing the processing cost, and finally obtaining a battery device 100 which is more economical.

[0098] In some embodiments, please refer to Figure 9 The second plate body 1012 is provided with a second through hole 10126 which communicates with the cavity 1013. The second through hole 10126 can guide the high-temperature substances in the cavity 1013 out, so as to reduce the residence time of the high-temperature substances in the battery device 100, thereby reducing the influence of the high-temperature substances on the battery device 100.

[0099] In some other embodiments, in the case where the second plate body 1012 is not provided with the second through hole 10126, the high-temperature substances can flow to the edge of the cavity 1013 through the cavity 1013 and contact the side wall of the box body 10, so as to increase the heat dissipation area of the box body 10 and achieve the purpose of rapid cooling, thereby reducing the influence of the high-temperature substances on the box body 10.

[0100] In some embodiments, the second through hole 10126 is arranged on the bottom wall of the groove 10121, and the second through hole 10126 does not overlap with the first through hole 10111 in the first direction. The high-temperature substances first flow into the cavity 1013 through the first through hole 10111, and then flow out to the side of the first wall 101 away from the battery monomer assembly through the second through hole 10126 during the flow in the cavity 1013, so as to reduce the influence of the high-temperature substances on the battery device 100.

[0101] In some embodiments, a plurality of recesses 10121 are provided, the recesses 10121 extend along the second direction, the plurality of recesses 10121 are spaced apart along the third direction, and the second through hole 10126 is arranged at at least one end of the recess 10121 along the second direction, the first direction, the second direction and the third direction are perpendicular to each other.

[0102] In the above embodiment, the high-temperature substance is discharged from the second through hole 10126 when flowing through the edge of the cavity 1013 during the process of flowing in the cavity 1013, which can make it difficult for the high-temperature substance to flow to the side wall of the box 10, thereby reducing the influence of the high-temperature substance on the entire battery device 100.

[0103] In some embodiments, along the first direction, the depth of the recess 10121 is d1, and d1 is 3-6 mm. Based on the characteristics of the process, compared with the current extrusion molding process, the depth of the recess 10121 can be made lower when the recess 10121 is formed by stamping molding, which can reduce the height of the pressure relief exhaust channel, thereby reducing the overall thickness of the first wall 101 and releasing the space of the battery device 100 in the first direction.

[0104] In some embodiments, the first wall 101 is used to carry the battery cell assembly, and the part of the first plate body 1011 connected to the battery cell assembly is a planar structure.

[0105] In the present embodiment, the first wall 101 is the bottom wall of the box 10, and the first wall 101 is used to carry the battery cell assembly to correspond to the downward application scenario of the pressure relief mechanism 201 of the battery cell 20. In other embodiments, the pressure relief mechanism 201 of the battery cell 20 is in a non-downward application scenario, and the first wall 101 can also be the top wall or the side wall of the box 10. The part of the first plate body 1011 connected to the battery cell assembly adopts a planar structure, which can reduce the abnormality of the locally formed first through hole 10111 structure caused by the local inclination of the first plate body 1011, and reduce the difficulty of meeting the explosion-proof pressure relief function of the battery device 100.

[0106] In some examples, the first plate body 1011 and the second plate body 1012 arranged in a split manner are first formed with a plurality of first through holes 10111 on the planar structure of the first plate body 1011 during the formation of the cavity 1013, and then the first plate body 1011 and the second plate body 1012 are connected to form the cavity 1013 therebetween. Because the first through hole 10111 is formed before the cavity 1013 is enclosed, the cavity 1013 is difficult to be affected by the process of forming the first through hole 10111.

[0107] In some embodiments, the second plate body 1012 includes a first connecting layer 10123 and a first reinforcing layer 10124, and the first connecting layer 10123 is located between the first reinforcing layer 10124 and the first plate body 1011 in the first direction, and the first connecting layer 10123 is connected to the first reinforcing layer 10124 and the first plate body 1011 respectively. The first reinforcing layer 10124 is arranged on the second plate body 1012, which can strengthen the overall strength of the first wall 101, and the first reinforcing layer 10124 is located on the opposite outer side of the box body 10. In some application scenarios, when the battery device 100 is impacted or scratched by foreign matter, the foreign matter will usually first contact the first reinforcing layer 10124, and the first reinforcing layer 10124 can reduce the damage of the foreign matter to other components due to its high strength, thereby reducing the impact when the battery device 100 is impacted or scratched, and improving the reliability of the battery device 100.

[0108] In some embodiments, the base material of the first connecting layer 10123 is aluminum. The base material is the material with the largest proportion in the first connecting layer 10123, and the base material of the first connecting layer 10123 is aluminum, which means that the material of the first connecting layer 10123 mainly contains aluminum, and the proportion of aluminum is the largest, but it does not mean that the first connecting layer 10123 is entirely made of aluminum. Aluminum has good corrosion resistance, and in some application scenarios, the cavity 1013 may include a cooling medium, and the aluminum layer can reduce the corrosion of the cooling medium to the first wall 101, thereby improving the service life of the box body 10.

[0109] In some embodiments, the thickness of the first connecting layer 10123 is 0.1mm-0.8mm. The greater the thickness of the first connecting layer 10123, the stronger the corrosion resistance of the second plate body 1012 obtained finally, but at the same time, the manufacturing cost will also increase. When the thickness of the above-mentioned embodiments is adopted, the corrosion resistance of the second plate body 1012 can meet the daily demand, and the manufacturing cost can also be effectively considered.

[0110] In some examples, the first connecting layer 10123 can be made of an aluminum plate with a thickness of 0.1mm-0.8mm.

[0111] In some embodiments, the base material of the first reinforcing layer 10124 is steel. The base material is the material with the largest proportion, and the base material of the first reinforcing layer 10124 is steel, which means that the first reinforcing layer 10124 is mainly made of steel, and the proportion of steel is the largest, but it does not mean that the first reinforcing layer 10124 is entirely made of steel. Steel has good heat resistance, and the temperature of the exhaust from the battery monomer 20 when the pressure relief mechanism 201 is actuated is very high. In some cases, the exhaust will break through the first connecting layer 10123, and when the base material of the first reinforcing layer 10124 is steel, it can not only improve the strength of the first wall 101, but also improve the heat resistance of the first wall 101 as a whole, and further improve the use reliability of the battery device 100. Moreover, when the base material of the first reinforcing layer 10124 is steel, because the heat resistance and strength of steel are high, it can support reducing the size of the cavity 1013 in the first direction, thereby reducing the space occupied by the box body 10 in the first direction.

[0112] In some embodiments, the base material of the first reinforcing layer 10124 can also be iron, titanium alloy, etc. The base material of the first connecting layer 10123 can also be stainless steel, titanium alloy, iron, etc.

[0113] In some embodiments, the thickness of the first reinforcing layer 10124 is 0.2mm-0.9mm. The greater the thickness of the first reinforcing layer 10124, the greater the strength of the second plate body 1012, but at the same time, its manufacturing cost will also increase. When the thickness of the above-mentioned embodiment is adopted, the strength of the second plate body 1012 meets certain requirements, while effectively taking into account its manufacturing cost.

[0114] In some examples, the first reinforcing layer 10124 can be a steel plate with a thickness of 0.2mm-0.9mm.

[0115] In some embodiments, the second plate body 1012 further comprises a first intermediate layer 10125, which is located between the first connecting layer 10123 and the first reinforcing layer 10124 along the first direction, and the first intermediate layer 10125 is connected with the first connecting layer 10123 and the first reinforcing layer 10124 respectively. When the first reinforcing layer 10124 and the first connecting layer 10123 adopt different base materials, high-temperature impact such as exhaust high-temperature substances, or when the first connecting layer 10123 is welded with the first plate body 1011, the first connecting layer 10123 and the first reinforcing layer 10124 may be delaminated. The setting of the first intermediate layer 10125 can improve the connectivity of the first connecting layer 10123 and the first reinforcing layer 10124, and effectively reduce the risk of delamination of the first reinforcing layer 10124 and the first connecting layer 10123 when the first wall 101 is subjected to high-temperature impact.

[0116] In some examples, when the base material of the first reinforcing layer 10124 is steel and the base material of the first connecting layer 10123 is aluminum, when high-temperature impact is applied, the high-temperature substance can break through the first connecting layer 10123 and directly contact the first reinforcing layer 10124, and brittle AlFe compounds can be generated in the area where the first connecting layer 10123 and the first reinforcing layer 10124 contact each other, which can cause the first connecting layer 10123 and the first reinforcing layer 10124 to delaminate. When the first intermediate layer 10125 is provided, the above situation can be effectively reduced.

[0117] In some embodiments, the base material of the first intermediate layer 10125 is nickel. Nickel has good stability and can reduce the mutual influence of the first connecting layer 10123 and the first reinforcing layer 10124 when the first connecting layer 10123 and the first reinforcing layer 10124 are subjected to thermal impact. In other embodiments, the base material of the first intermediate layer 10125 can also be gold, titanium alloy, etc.

[0118] In some embodiments, the thickness of the first intermediate layer 10125 is 5-10 μm. In consideration of manufacturing cost, the thickness of the first intermediate layer 10125 should be as thin as possible. When the thickness in the above embodiments is used, the first connecting layer 10123 and the first reinforcing layer 10124 can be effectively blocked, and the manufacturing cost of the second plate body 1012 can also be effectively considered.

[0119] In some examples, the first intermediate layer 10125 can be a nickel plate with a thickness of 5-10 μm.

[0120] In some embodiments, the thickness of the second plate body 1012 is d2, and d2 is 1-2 mm. When this thickness is used, the strength of the first wall 101 can meet certain requirements, and the space occupied by the first wall 101 in the first direction can be as low as possible.

[0121] In some embodiments, the base material of the first plate body 1011 is aluminum, and the first plate body 1011 is welded to the first connecting layer 10123. On the one hand, the first plate body 1011 is provided as an aluminum layer to reduce the influence of the cooling medium on the first wall 101. On the other hand, the base materials of the first plate body 1011 and the first connecting layer 10123 are both aluminum, which facilitates welding of the two, thereby achieving better connectivity.

[0122] In some embodiments, the first plate body 1011 includes a second connecting layer 10112 and a second reinforcing layer 10113, the second connecting layer 10112 is arranged between the second reinforcing layer 10113 and the first connecting layer 10123, and the second connecting layer 10112 is connected with the first connecting layer 10123. The second connecting layer 10112 is connected with the first connecting layer 10123, and the second reinforcing layer 10113 is arranged, which can further improve the overall strength of the first wall 101 and better protect the battery monomer 20 assembly.

[0123] In some embodiments, the base material of the second connecting layer 10112 is aluminum, and the second connecting layer 10112 is welded with the first connecting layer 10123. The base material of the second connecting layer 10112 is aluminum, which facilitates the welding with the first connecting layer 10123.

[0124] In some examples, the base material of the first connecting layer 10123 and the second connecting layer 10112 can both be aluminum.

[0125] In some embodiments, the base material of the second reinforcing layer 10113 is steel. Steel has good heat resistance, and the temperature of the discharge from the battery monomer 20 when the pressure relief mechanism 201 is actuated is very high. In some cases, the discharge can break through the second connecting layer 10112. When the base material of the second reinforcing layer 10113 is steel, it can not only improve the overall strength of the first wall 101, but also improve the overall heat resistance of the first wall 101, further improving the use reliability of the battery device 100. In some other embodiments, the base material of the second reinforcing layer 10113 can also be iron, titanium alloy, etc. The base material of the second connecting layer 10112 can also be stainless steel, titanium alloy, iron, etc.

[0126] In some embodiments, the thickness of the second reinforcing layer 10113 can be 0.2mm-0.9mm. The greater the thickness of the second reinforcing layer 10113, the greater the strength of the first wall 101, but at the same time, its manufacturing cost will also increase. When the thickness of the above-mentioned embodiments is adopted, the strength of the first wall 101 can meet certain requirements while effectively taking into account its manufacturing cost.

[0127] In some examples, the second reinforcing layer 10113 can be steel with a thickness of 0.2mm-0.9mm.

[0128] In some embodiments, the thickness of the second connecting layer 10112 is 0.1mm-0.8mm. In some examples, the second connecting layer 10112 can be aluminum with a thickness of 0.1mm-0.8mm.

[0129] In some embodiments, the first plate body 1011 further comprises a second intermediate layer 10114, which is located between the second connecting layer 10112 and the second reinforcing layer 10113 in the first direction, and is connected with the second connecting layer 10112 and the second reinforcing layer 10113 respectively. When the second reinforcing layer 10113 and the second connecting layer 10112 are made of different base materials, the second connecting layer 10112 may be delaminated from the second reinforcing layer 10113 when subjected to high-temperature impact, such as high-temperature substances discharged, or when the second connecting layer 10112 is welded with the second plate body 1012. The second intermediate layer 10114 can improve the connectivity of the second connecting layer 10112 and the second reinforcing layer 10113, and effectively reduce the risk of delamination of the second reinforcing layer 10113 and the second connecting layer 10112 when the first wall 101 is subjected to high-temperature impact.

[0130] In some embodiments, the base material of the second intermediate layer 10114 is nickel. Nickel has good stability and can reduce the mutual influence of the second connecting layer 10112 and the second reinforcing layer 10113 when they are subjected to thermal impact. In other embodiments, the base material of the second intermediate layer 10114 can also be gold, titanium alloy, etc.

[0131] In some embodiments, the thickness of the second intermediate layer 10114 is 5-10 μm. Considering the manufacturing cost, the thickness of the second intermediate layer 10114 should be as thin as possible. When the thickness in the above embodiments is adopted, the second connecting layer 10112 and the second reinforcing layer 10113 can be effectively blocked, and the manufacturing cost of the first plate body 1011 can also be effectively considered.

[0132] In some examples, the second intermediate layer 10114 can be a nickel plate with a thickness of 5-10 μm.

[0133] In some embodiments, the thickness of the first plate body 1011 is d3, and d3 is 0.5-2 mm. When this thickness is adopted, the strength of the first wall 101 can meet certain requirements, and the first through hole 10111 can also be easily formed.

[0134] In some embodiments, the second plate body 1012 can be formed by one-piece stamping, and the recess 10121 is formed. The final box 10 has low molding cost and high molding efficiency.

[0135] In some examples, the thickness of the first wall 101 needs to be larger due to the extrusion process of the cavity 1013. In some embodiments of the present application, when the second plate body 1012 is formed by punching, the thickness of the first wall 101 can be smaller compared to the extrusion process, thereby achieving the purpose of reducing the space occupied by the box body 10 in the first direction.

[0136] In some embodiments, the first through hole 10111 is formed by punching.

[0137] The punching method of the through hole has the advantage of being able to form multiple through holes at one time. The current box body 10 is pre-formed with a cavity 1013, and then a through hole is formed on the cavity wall of the cavity 1013. If the punching process is used, the cavity 1013 is likely to be damaged, thereby reducing the yield of the box body 10. Therefore, it is difficult to use the punching process to form the through hole of the current box body 10. Currently, multiple through holes are formed on the plate body in sequence by mechanical processing. However, the mechanical processing method for forming the through hole has the disadvantages of high processing cost and low processing efficiency, thereby resulting in low economic efficiency of the battery device.

[0138] In some embodiments of the present application, because the first plate body 1011 and the second plate body 1012 are separately arranged, multiple first through holes 10111 can be formed on the first plate body 1011 by punching at one time, without worrying about the impact of the punching process on the cavity 1013. Compared to the current mechanical processing method for forming multiple first through holes 10111, the battery device 100 provided by the embodiments of the present application can support the punching of the first plate body 1011 to form multiple first through holes 10111 at one time, which has the advantages of low processing cost and high processing efficiency, thereby achieving the purpose of improving the economic efficiency of the battery device 100.

[0139] In some examples, the part of the first plate body 1011 connected to the battery cell assembly adopts a flat structure, and the punching process for forming the first through hole 10111 is difficult to affect the structure of the first plate body 1011 itself.

[0140] According to some embodiments of the present application, a battery device 100 is provided, comprising a box 10 and a battery cell assembly, the box 10 comprising a first wall 101, the battery cell assembly being at least partially accommodated in the box 10, the battery cell assembly comprising a plurality of battery cells 20, each of the battery cells 20 being provided with a pressure relief mechanism 201 on a side facing the first wall 101. The first wall 101 comprises a first plate body 1011 and a second plate body 1012 which are separately provided and connected to each other, along a first direction, the first plate body 1011 is arranged between the battery cell assembly and the second plate body 1012, the first plate body 1011 is provided with a first through hole 10111, the first through hole 10111 is arranged opposite to the pressure relief mechanism 201, the first direction is the thickness direction of the first wall 101. A cavity 1013 is formed between the first plate body 1011 and the second plate body 1012, the cavity 1013 is in communication with the first through hole 10111, the cavity 1013 is used to collect the discharge from the battery cell 20 provided with the pressure relief mechanism 201 when the pressure relief mechanism 201 is actuated. The first wall 101 is the bottom wall of the box 10, used to carry the battery cell assembly. The first plate body 1011 is a flat plate structure, the second plate body 1012 comprises a first connecting layer 10123, a first reinforcing layer 10124 and a first intermediate layer 10125, along the first direction, the first connecting layer 10123 is located between the first reinforcing layer 10124 and the first plate body 1011, the first intermediate layer 10125 is located between the first connecting layer 10123 and the first reinforcing layer 10124, and the first intermediate layer 10125 is connected to the first connecting layer 10123 and the first reinforcing layer respectively. The base material of the first reinforcing layer 10124 is steel, the base material of the first connecting layer 10123 is aluminum, the base material of the first intermediate layer 10125 is nickel, the base material of the first plate body 1011 is aluminum, and the first plate body 1011 is welded to the first connecting layer 10123. The thickness of the first plate body 1011 is 0.5mm-2mm, and the thickness of the second plate body 1012 is 1mm-2mm. The second plate body 1012 is formed with a groove on a side facing the first plate body 1011, and a protrusion corresponding to the groove is formed on a side of the second plate body 1012 away from the first plate body 1011, the first plate body 1011 covers the groove to form the cavity 1013, along the first direction, the depth of the groove is 3mm-6mm. The second plate body 1012 is provided with a second through hole 10126 in communication with the cavity 1013, the second through hole 10126 is arranged on the bottom wall of the groove, along the first direction, the second through hole 10126 does not overlap with the first through hole 10111, the groove is provided with a plurality of grooves, the grooves extend along a second direction, the plurality of grooves are arranged at intervals along a third direction, the second through hole 10126 is arranged at at least one end of the grooves along the second direction, the first direction, the second direction and the third direction are perpendicular to each other, and the first through hole 10111 is formed by stamping.

[0141] Although the present application has been described with reference to preferred embodiments, various modifications can be made to the application without departing from the scope of the application. In particular, the technical features mentioned in the various embodiments can be combined in any way, provided that there is no structural conflict. The present 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 by, The application relates to a battery box. The battery box comprises: a box body comprising a first wall; a battery cell assembly at least partially accommodated in the box body, the battery cell assembly comprising a plurality of battery cells; wherein the first wall comprises a first plate body and a second plate body arranged separately and connected to each other, the first plate body is arranged between the battery cell assembly and the second plate body along a first direction, the first direction being the thickness direction of the first wall; 2. The battery device according to claim 1, characterized by the second plate body is provided with a groove recessed in a direction away from the first plate body and a protrusion protruding in a direction towards the first plate body, the first plate body covers the groove to form a cavity, and the first plate body is connected to the protrusion.

3. The battery device of claim 2, wherein, The side of the battery cell towards the first wall is provided with a pressure relief mechanism, the first plate body is provided with a first through hole, the first through hole is arranged opposite to the pressure relief mechanism, and the first through hole is in communication with the cavity.

4. The battery device of claim 3, wherein The second plate body is provided with a second through hole in communication with the cavity.

5. The battery device according to claim 3 or 4, characterized by The second through hole is arranged on the bottom wall of the groove, and the second through hole does not overlap with the first through hole along the first direction.

6. The battery device of claim 1, wherein The groove is provided with a plurality of grooves, the grooves extend along a second direction, a plurality of grooves are arranged at intervals along a third direction, the second through hole is arranged at at least one end of the groove along the second direction, and the first direction, the second direction and the third direction are perpendicular to each other.

7. The battery device of claim 1, wherein The depth of the groove along the first direction is 3mm-6mm.

8. The battery device of claim 1, wherein The first wall is used for bearing the battery cell assembly, and the part of the first plate body connected to the battery cell assembly is a planar structure.

9. The battery device of claim 8, wherein, The second plate body comprises a first connecting layer and a first reinforcing layer, the first connecting layer is located between the first reinforcing layer and the first plate body along the first direction, and the first connecting layer is connected to the first plate body.

10. The battery device of claim 8, wherein, The base material of the first connecting layer is aluminum.

11. The battery device of claim 8, wherein, The base material of the first reinforcing layer is steel.

12. The battery device of claim 8, wherein, The thickness of the first reinforcing layer is 0.2mm-0.9mm, and / or the thickness of the first connecting layer is 0.1mm-0.8mm.

13. The battery device of claim 12, wherein, The second plate body further comprises a first intermediate layer, the first intermediate layer is located between the first connecting layer and the first reinforcing layer along the first direction, and the first intermediate layer is connected to the first connecting layer and the first reinforcing layer respectively.

14. The battery device of claim 12, wherein, The base material of the first intermediate layer is nickel.

15. The battery device according to any one of claims 8 to 14, characterized by, The thickness of the first intermediate layer is 5um-10um.

16. The battery device according to any one of claims 8 to 14, wherein The thickness of the second plate body is 1mm-2mm.

17. The battery device according to any one of claims 8 to 14, wherein The base material of the first plate body is aluminum, and the first plate body is welded to the first connecting layer.

18. The battery device of claim 17, wherein, The first plate body comprises a second connecting layer and a second reinforcing layer, the second connecting layer is arranged between the second reinforcing layer and the first connecting layer, and the second connecting layer is connected to the first connecting layer.

19. The battery device of claim 17, wherein, The base material of the second connecting layer is aluminum, and the second connecting layer is welded to the first connecting layer.

20. The battery device of claim 17, wherein, The base material of the second reinforcing layer is steel. The thickness of the second reinforcing layer is 0.2mm-0.9mm, and / or the thickness of the second connecting layer is 0.1mm-0.8mm.

21. The battery device of claim 17, wherein, The first plate body further comprises a second intermediate layer, which is located between the second connecting layer and the second reinforcing layer along the first direction, and which is connected with the second connecting layer and the second reinforcing layer respectively.

22. The battery device of claim 21, wherein, The base material of the second intermediate layer is nickel.

23. The battery device of claim 21, wherein, The thickness of the second intermediate layer is 5 μm-10 μm.

24. The battery device of claim 21, wherein, The thickness of the first plate body is 0.5 mm-2 mm.

25. An electrical device, comprising: A battery device comprising any one of claims 1-24.

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