Battery devices and electrical equipment

Abstract

The present application relates to the field of battery technology and provides a battery device and electrical equipment. The battery device includes a battery cell assembly, a box body, and a pressure relief mechanism. A first through hole connected to the accommodating space is provided on the outer wall of the box body. The pressure relief mechanism is provided at the first through hole. The pressure relief mechanism includes a base, a pressure relief member, and a cover plate. A second through hole opposite to the first through hole is provided on the base. The pressure relief member includes a sealing film and a metal deformation member. The sealing film blocks the second through hole. The metal deformation member is provided on the base and spaced apart from the sealing film. The metal deformation member includes a fixing portion connected to the base, a deformation portion, and a puncture portion. The deformation portion protrudes toward the sealing film when heated. Moreover, the deformation portion does not block the first through hole. The puncture portion punctures the sealing film to achieve communication between the second through hole and the outside. In the battery device provided by the present application, the pressure relief mechanism has lower processing accuracy requirements and higher reliability.

Description

Technical Field

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

[0002] Battery devices are widely used in vehicles to provide electric propulsion. To meet the high power requirements of vehicles, batteries are often used as a power source.

[0003] To mitigate the risks of thermal runaway in battery devices, a pressure relief mechanism is typically installed on the battery housing to achieve directional pressure relief. Currently, this mechanism works by deforming a shape memory alloy upon heating, tearing through a weak area within the mechanism and creating a vent for pressure relief.

[0004] However, this pressure relief method requires high machining precision. Specifically, the machining accuracy of the weak area must precisely match the force generated by the thermal deformation of the shape memory alloy to ensure effective tearing and the formation of the pressure relief vent. If the strength of the weak area is too high, it may not tear, thus affecting the pressure relief effect. If the strength is too low, it may cause reliability issues during normal use, such as airtightness failure and water leakage. Summary of the Invention

[0005] The purpose of the embodiments of the present application is to provide a battery device and an electrical device, aiming to solve the problems of high processing precision requirements and relatively low reliability of the pressure relief mechanism in the battery device.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are:

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

[0008] A battery cell assembly, the battery cell assembly comprising a plurality of battery cells arranged in parallel;

[0009] a box body having a housing space for housing the battery cell group;

[0010] A pressure relief mechanism, wherein a first through hole communicating with the accommodating space is provided on an outer wall of the box body, the pressure relief mechanism is provided at the first through hole, the pressure relief mechanism comprising a base provided on the box body, a pressure relief member, and a cover provided on the base and covering the pressure relief member, the base being provided with a second through hole arranged opposite to the first through hole;

[0011] The pressure relief component includes a sealing film and a metal deformable component, the sealing film blocks the second through hole, and the metal deformable component is arranged on the base and spaced apart from the sealing film; the metal deformable component includes a fixed portion connected to the base, a deformable portion connected to the fixed portion, and a puncture portion provided on the deformable portion, the deformable portion protrudes toward the sealing film when heated, and the deformable portion does not block the first through hole, and the puncture portion punctures the sealing film to achieve communication between the second through hole and the outside.

[0012] Beneficial effects of the embodiments of the present application: In the battery device provided by the embodiments of the present application, in the initial state, the sealing membrane of the pressure relief part blocks the second through hole to achieve the sealing requirements of the battery device under normal use. When the battery cell assembly experiences thermal runaway in the storage space of the box, the valve spray leaks out from the first through hole, and, under the directional pressure relief action of the pressure relief mechanism, is discharged from the second through hole to the outside. Specifically, the valve spray is usually accompanied by high temperature, and the metal deformation part is more sensitive to temperature changes. That is, the deformation part of the metal deformation part will protrude away from the box when heated, and drive the puncture part to move toward the sealing membrane, so that the puncture part punctures the sealing membrane, so that the second through hole is connected to the outside, and the valve spray is discharged from the second through hole. The battery device provided by the present application has lower processing accuracy requirements for the pressure relief mechanism, and the use of a sealing membrane for sealing has higher reliability.

[0013] In some embodiments, the deformation amount of the deformable portion protruding toward the sealing film when heated is greater than the distance from the puncture portion away from one end of the deformable portion to the sealing film.

[0014] By sampling the above technical solution, the deformation amount of the deformation part should be greater than the distance from the puncture part away from one end of the deformation part to the sealing film, so as to achieve directional pressure relief of the battery device when thermal runaway occurs.

[0015] In some embodiments, the deformable portion includes a deformable sheet, the deformable sheet includes a sheet main body and a plurality of extension portions provided on the sheet main body, the number of the fixed portions is multiple, each of the extension portions is connected to the corresponding fixed portion, and the puncture portion is provided on the sheet main body.

[0016] By sampling the above technical solution, the main body of the sheet is the main part of the deformable sheet that undergoes deformation, and the extended part is the part of the deformable sheet that is connected to the fixed part. Then, when the main body of the sheet is deformed by heat, under the fixed action of the connection between the extended part and the fixed part, the main body of the sheet drives the puncture part to move toward the sealing film and destroy the sealing film.

[0017] In some embodiments, the deformation portion includes a spiral telescopic column, one end of the spiral telescopic column is provided at the puncture portion, and the other end of the spiral telescopic column is connected to the fixing portion.

[0018] By sampling the above technical solution, similarly, the spiral telescopic cylinder as a whole extends along its own axial direction when heated, thereby driving the puncture part to move toward the sealing film and destroy the sealing film.

[0019] In some embodiments, the metal deformable member is a thermal memory deformable metal.

[0020] In some embodiments, the deformation portion is a thermal memory deformation metal.

[0021] In some embodiments, the thermosensitive shape memory metal includes any one of a Ni-Ti based shape memory alloy, a Cu based shape memory alloy, a Ni-Mn based shape memory alloy, and a Fe based shape memory alloy.

[0022] In some embodiments, a concave cavity connected to the second through hole is provided on the base, the cover plate is arranged in the concave cavity, and the side wall of the cover plate is in contact with the inner wall of the concave cavity. At least one groove is provided on the side wall of the concave cavity, and the groove wall of the groove is inclined.

[0023] By sampling the above technical solution, when thermal runaway occurs in the battery device, pressure can be released through the groove, and the groove with an inclined groove wall can also reduce the probability of water accumulation between the base and the cover.

[0024] In some embodiments, the pressure relief mechanism includes a seal disposed between the base and an outer wall of the box.

[0025] By sampling the above technical solution, a seal is used to improve the sealing performance of the connection between the base and the outer wall of the box.

[0026] In a second aspect, an embodiment of the present application further provides an electrical device comprising the battery device described above.

[0027] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. 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 any creative work.

[0029] Figure 1 A schematic diagram of the structure of the electrical equipment provided in the embodiment of the present application;

[0030] Figure 2 A schematic diagram of the structure of a battery device provided in an embodiment of the present application;

[0031] Figure 3 An exploded view of a battery cell provided in an embodiment of the present application;

[0032] Figure 4 An exploded view of the housing and pressure relief mechanism of the battery device provided in an embodiment of the present application;

[0033] Figure 5 An exploded view of the pressure relief mechanism of the battery device provided in an embodiment of the present application;

[0034] Figure 6 A cross-sectional view of a pressure relief mechanism of a battery device provided in an embodiment of the present application;

[0035] Figure 7 A schematic structural diagram of a metal deformable member of a pressure relief member of a pressure relief mechanism of a battery device provided in an embodiment of the present application;

[0036] Figure 8 Another structural schematic diagram of the metal deformable member of the pressure relief member of the pressure relief mechanism of the battery device provided in an embodiment of the present application.

[0037] Among them, the reference numerals in the figures are:

[0038] 1000, vehicle; 200, controller; 300, motor;

[0039] 100, battery device; 10, housing; 11, first housing; 12, second housing; 10a, accommodating space; 20, battery cell; 10b, first through hole;

[0040] 30. Pressure relief mechanism; 31. Base; 32. Cover; 33. Pressure relief member; 31a. Second through hole; 331b. Sealing membrane; 332b. Metal deformation member; 332b1. Fixing portion; 332b2. Deformation portion; 332b3. Puncture portion; 332b21. Sheet body; 332b22. Extension portion; 31e. Concave cavity; 31f. Groove; 35. Sealing member. DETAILED DESCRIPTION

[0041] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0042] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0044] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0045] In related technologies, a battery device includes a housing and a battery cell assembly housed within the housing. To ensure targeted pressure relief in the event of thermal runaway, a pressure relief mechanism is typically installed on the outer wall of the housing. This pressure relief mechanism corresponds to a pressure relief channel within the housing.

[0046] However, the current pressure relief mechanism's pressure relief principle is based on the deformation of shape memory alloys upon heating, which tears the weak areas of the pressure relief mechanism, thereby forming an exhaust port for pressure relief. This pressure relief method requires high machining precision. Specifically, the machining precision of the weak areas must precisely match the force generated by the thermal deformation of the shape memory alloy to ensure effective tearing and formation of the pressure relief port. If the strength of the weak areas is too high, it may prevent tearing, thus affecting the pressure relief effect; if the strength is too low, it will cause reliability issues during normal use, such as airtightness failure and water leakage.

[0047] In view of this, the present application provides a battery device, wherein the pressure relief mechanism provided on the outer wall of the housing comprises a base, a pressure relief member, and a cover. The pressure relief member is a structural component that deforms when heated. Specifically, in the initial state, the pressure relief member seals the second through-hole on the base to meet the sealing requirements of the battery device during normal use. In the unsealed state, the pressure relief member protrudes away from the housing due to heat, thereby connecting the second through-hole to the outside. Then, the spray valve material in the housing passes through the first through-hole and the second through-hole to the outside, thereby achieving directional pressure relief.

[0048] The battery cells disclosed in the embodiments of the present application can be used in electrical devices that use the battery device as a power source or various energy storage systems that use the battery device as an energy storage element. The electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery-powered vehicles, electric vehicles, ships, spacecraft, and the like. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like, and spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0049] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0050] Please refer to Figure 1 , Figure 1 A schematic structural diagram 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. 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. 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 serve as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and operating power requirements of the vehicle 1000 during driving.

[0051] In some embodiments of the present application, the battery device 100 can serve not only as an operating power source for the vehicle 1000 , but also 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 .

[0052] Please refer to Figure 2 , Figure 2An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 described in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assemblies may include multiple battery cells 20, which are connected in series, parallel, or in parallel via a busbar.

[0053] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells 20 .

[0054] As an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of battery cells 20 to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells 20 with a cable tie.

[0055] In some embodiments, the battery device 100 may be a battery pack, which includes a case 10 and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case 10 .

[0056] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box body 10 by fixing the battery module in the box body 10 .

[0057] As an example, the battery cell assembly may also be housed in the case 10 by directly fixing the plurality of battery cells 20 to the case 10 .

[0058] As an example, the housing 10 may include a first housing 11 and a second housing 12. The first housing 11 and the second housing 12 engage to form an enclosed space within the housing 10 for accommodating the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first housing 11 may be a top cover or a bottom plate.

[0059] As an example, the box body 10 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body 10 to accommodate the battery cell assembly.

[0060] In some embodiments, the box 10 may serve as part of the chassis structure of the vehicle 1000. For example, a portion of the box 10 may form at least a portion of the floor of the vehicle 1000, or a portion of the box 10 may form at least a portion of the cross member and longitudinal member of the vehicle 1000.

[0061] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery cells 20, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0062] In the embodiment of the present application, the battery cell 20 may be a secondary battery. A secondary battery refers to a battery cell 20 that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0063] The battery cell 20 can 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 metal hydride battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiment of the present application.

[0064] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the exploded structure of a battery cell 20 provided in some embodiments of the present application. A battery cell 20 is the smallest unit that constitutes a battery device 100. A plurality of battery cells 20 arranged in parallel constitute a battery cell assembly. Figure 3 The battery cell 20 includes an end cap 21, a shell 22, an electrode assembly 23 and other functional components.

[0065] The end cap 21 is a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the end cap 21 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cap 21 can be made of a material with a certain degree of hardness and strength (such as an aluminum alloy). This prevents deformation of the end cap 21 during compression and collision, providing the battery cell 20 with greater structural strength and improved reliability. The end cap 21 can be provided with functional components such as electrode terminals. The electrode terminals can be used to electrically connect to the electrode assembly 23 for inputting or outputting electrical energy from the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism to release internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The end cap 21 can be made of a variety of materials, including, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic. In some embodiments, an insulating member may be provided inside the end cap 21 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 made of plastic, rubber, or the like.

[0066] The housing 22 is a component that cooperates with the end cap 21 to form the internal environment of the battery cell 20. This internal environment can be used to accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and end cap 21 can be separate components. An opening can be provided in the housing 22, and the end cap 21 is placed over the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 21 and housing 22 can be integrated. Specifically, the end cap 21 and housing 22 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 22 needs to be enclosed, the end cap 21 is placed over the housing 22. The housing 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylinder, or a hexagonal prism. Specifically, the shape of the housing 22 can be determined based on the specific shape and size of the electrode assembly 23. The housing 22 can be made of a variety of materials, such as, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0067] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 23 may be contained 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. The positive and negative electrode tabs 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 electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0068] Please refer to Figures 4 to 7 The battery device 100 provided in an embodiment of the present application includes a battery cell assembly, a box body 10 and a pressure relief mechanism 30.

[0069] Among them, the battery cell assembly includes a plurality of battery cells 20 arranged in parallel; the box body 10 has an accommodating space 10a for accommodating the battery cell group; a first through hole 10b connected to the accommodating space 10a is provided on the outer wall of the box body 10, and the pressure relief mechanism 30 is provided at the first through hole 10b. The pressure relief mechanism 30 includes a base 31 provided on the box body 10, a pressure relief member 33 and a cover plate 32 provided on the base 31 and covering the pressure relief member 33. A second through hole 31a arranged opposite to the first through hole 10b is provided on the base 31. The pressure relief member 33 blocks the second through hole 31a, and the pressure relief member 33 protrudes in a direction away from the box body 10 when heated, so that the second through hole 31a is connected to the outside.

[0070] It is understood that the pressure relief mechanism 30 is a mechanism for achieving directional pressure relief in the event of thermal runaway of the battery device. Generally, the pressure relief mechanism 30 can be an explosion-proof valve, a pressure relief valve, or a relatively weak structure formed on the box body 10.

[0071] The pressure relief mechanism 30 in this embodiment is similar to an explosion-proof valve, and includes a base 31, a pressure relief member 33, and a cover plate 32. The base 31 is the main part of the pressure relief mechanism 30, and the base 31 is used to connect to the outer wall of the box body 10. What needs to be satisfied is that the second through hole 31a on the base 31 corresponds to the first through hole 10b on the box body 10. The sealing film 331b and the metal deformation member 332b in the pressure relief member 33 respectively realize the two functions of sealing and valve opening. When the battery device is in normal use, the sealing film 331b blocks the second through hole 31a to meet the sealing requirements of the battery device; and when the battery device has thermal runaway, the metal deformation member 332b can pierce the sealing film 331b to connect the second through hole 31a to meet the requirements of the battery device for a directional pressure relief spray valve. Here, metal deformable member 332b is a heat-sensitive structural component. At room temperature, metal deformable member 332b maintains its shape and structure to meet sealing requirements. When the external temperature exceeds the deformation temperature threshold of metal deformable member 332b, metal deformable member 332b deforms. Cover plate 32 provides protection and safeguards, reducing the probability of pressure relief member 33 being directly opened by external factors.

[0072] Here, sealing membrane 331b is a membrane structure that directly seals second through-hole 31a. Sealing membrane 331b can be made of various engineering plastics, such as PET, ABS, PP, and PA, offering lightweight and reliable performance. For example, e-PTFE or polyimide are preferred as base materials for sealing membrane 331b. These materials can be combined with structural design (e.g., pre-tensioning, needle optimization) and composite material strategies (e.g., fiber reinforcement or metal plating) to achieve rapid rupture characteristics at low elongation.

[0073] The metal deformable member 332b can be made of a thermo-sensitive shape memory metal. Thermo-sensitive shape memory metals (also known as thermal shape memory alloys, SMAs) are a type of smart material capable of triggering shape recovery through temperature changes. Based on the principle of thermoelastic martensitic transformation, these alloys can recover a pre-set shape at a specific temperature. Specifically, at room temperature, the metal deformable member 332b maintains its original structural form. However, after thermal runaway of the battery device, the valve creates a high-temperature environment at the pressure relief mechanism 30. When this ambient temperature exceeds the temperature threshold of the metal deformable member 332b, the metal deformable member 332b deforms. Specifically, the metal deformable member 332b protrudes toward the sealing membrane 331b, thereby destroying the sealing membrane 331b. Here, the metal deformable member 332b protruding toward the sealing membrane 331b is synonymous with the metal deformable member 332b protruding away from the housing 10.

[0074] Specifically, the fixing portion 332b1 is the portion of the metal deformable part 332b that is connected to the base 31 and is fixed; the deformable part 332b2 is the portion of the metal deformable part 332b that is deformed by heat, and the main deformation mode of the deformable part 332b2 is to protrude toward the sealing film 331b; the puncture portion 332b3 is the portion of the metal deformable part 332b that protrudes and moves with the deformable part 332b2, and the puncture portion 332b3 should be a structural part with a pointed tip. For example, the puncture portion 332b3 can be a needle-shaped structure or a cone-shaped structure. Then, the puncture portion 332b3 should have one end connected to the deformable part 332b2 and the other end extending toward the sealing film 331b. In this way, under the drive of the deformable part 332b2, the end of the puncture portion 332b3 away from the deformable part 332b2 can puncture and destroy the sealing film 331b.

[0075] Here, the deformable portion 332b2 is made of a thermal memory deformable metal. For example, at room temperature, the deformable portion 332b2 is stationary and maintains a certain distance from the sealing membrane 331b. However, if the battery device experiences thermal runaway, the valve spray rapidly raises the ambient temperature at the pressure relief mechanism 30. When the ambient temperature exceeds the deformation temperature threshold of the deformable portion 332b2, the deformable portion 332b2 deforms, primarily by bulging the portion of the deformable portion 332b2 away from its connection with the fixed portion 332b1 toward the sealing membrane 331b.

[0076] For example, the deformable portion 332b2 may be a Ni-Ti-based shape memory alloy, a Cu-based shape memory alloy, a Ni-Mn-based shape memory alloy, or an Fe-based shape memory alloy. For example, the deformable portion 332b2 may be a Ni-Ti alloy, and its phase transition temperature may be controlled by adjusting the Ni / Ti ratio or adding a third metal element (Cu, Fe). Alternatively, the deformable portion 332b2 may be a Cu-Zn-Al alloy or a Cu-Al-Ni alloy. Alternatively, the deformable portion 332b2 may be a Ni-Mn-Ga alloy, a Ni-Mn-In alloy, or a Ni-Mn-Sn alloy. The deformable portion 332b2 may be a Fe-Mn-Si alloy, a Fe-Pd alloy, or a Fe-Ni-Co-Ti alloy.

[0077] Taking a Cu-based shape memory alloy as an example, the deformation portion 332b2 can be made of a Cu-Zn-Al-Ni alloy, and the phase transition temperature can be adjusted by adjusting the mass ratio of Zn, Al, and Ni. The phase transition temperature of the Cu-Zn-Al-Ni alloy is between 80-120°C. That is, when the temperature exceeds 80°C, the deformation portion 332b2 begins to deform. Under normal conditions, the surface temperature of the battery device casing should not exceed 60°C. However, in the thermal runaway state, the battery device casing rapidly heats up to meet the temperature requirements for deformation of the deformation portion 332b2.

[0078] Furthermore, the deformable portion 332b2 does not need to block the first through hole 10b. That is, the deformable portion 332b2 deforms due to its own thermal sensitivity, rather than relying on the impact force of the nozzle during thermal runaway to provide the necessary deformation force. Therefore, the deformable portion 332b2 may have corresponding gaps in its structure, such as a hollow structure or holes or grooves directly formed in the deformable portion 332b2. This allows the deformable portion 332b2 to more easily deform and bulge toward the sealing membrane under the action of heat.

[0079] For example, the deformable portion 332b2 can have a petal-like structure. The center of this deformable portion 332b2 is located at the point where it experiences the greatest convex deformation upon heating, thus satisfying the non-blocking requirement. Thus, the puncture portion 332b3 can be positioned at the center of this deformable portion 332b2. Once deformed by heat, the center of the deformable portion 332b2 bulges, exhibiting a convex deformation pattern. This can drive the puncture portion 332b3 toward the sealing membrane 331b, thereby puncturing and destroying the sealing membrane 331b.

[0080] For example, the deformable portion 332b2 can also be a spring-like spiral structure, similar to the non-blocking requirement. This type of deformable portion 332b2 deforms in an axially extending manner upon heating. Thus, the puncture portion 332b3 can be positioned along the central axis of the deformable portion 332b2. Once deformed by heat, the free end of the deformable portion 332b2, not connected to the fixed portion 332b1, convexly extends in the axial direction, driving the puncture portion 332b3 toward the sealing membrane 331b to puncture and destroy the sealing membrane 331b.

[0081] In the battery device provided in the embodiment of the present application, in the initial state, the sealing film 331b of the pressure relief member 33 blocks the second through hole 31a to achieve the sealing requirement of the battery device under normal use. When the battery cell assembly experiences thermal runaway in the accommodating space 10a of the box body 10, the valve substance is discharged from the first through hole 10b, and is discharged to the outside from the second through hole 31a under the directional pressure relief action of the pressure relief mechanism 30. Specifically, the valve substance is usually accompanied by high temperature, and the metal deformable member 332b is more sensitive to temperature changes. That is, the deformable portion 332b2 of the metal deformable member 332b will protrude away from the box body 10 when heated, and drive the puncture portion 332b3 to move toward the sealing film 331b, so that the puncture portion 332b3 pierces the sealing film 331b, thereby connecting the second through hole 31a to the outside, and thereby enabling the valve substance to be discharged from the second through hole 31a. In the battery device provided in the present application, the pressure relief mechanism 30 has lower processing precision requirements and is sealed with a sealing film 331 b , thereby achieving higher reliability.

[0082] Please refer to Figure 6 and Figure 8 In some embodiments, the deformation amount of the deformable portion 332b2 protruding toward the sealing film 331b when heated is greater than the distance between the puncture portion 332b3 and the sealing film 331b from one end of the deformable portion 332b2.

[0083] It can be understood that the deformation amount of the deformable portion 332b2 that protrudes toward the sealing film 331b when heated should refer to the displacement of the position where it is connected to the puncture portion 332b3. For example, when the deformable portion 332b2 is a basin-shaped structure or a petal structure, its deformation amount is the displacement of the protruding vertex of the basin-shaped structure or the petal structure in the plane where the deformable portion 332b2 and the fixed portion 332b1 are connected. Or, when the deformable portion 332b2 is a spiral structure similar to a spring structure, its deformation amount is the deformation elongation of the spiral structure, that is, the deformation amount is equal to the length of the spiral structure after deformation minus the length of the spiral structure before deformation.

[0084] The puncture portion 332b3 should have one end connected to the deformation portion 332b2 and the other end protruding toward the sealing film 331b, and the end of the puncture portion 332b3 facing the sealing film 331b is called the puncture end. The distance N from the end of the puncture portion 332b3 away from the deformation portion 332b2 to the sealing film 331b refers to the shortest distance from the puncture end of the puncture portion 332b3 to the sealing film 331b. Therefore, when the deformation amount of the puncture portion 332b2 protruding toward the sealing film 331b when heated is greater than the distance N from the end of the puncture portion 332b3 away from the deformation portion 332b2 to the sealing film 331b, the puncture portion 332b3 can damage the sealing film 331b and the second through hole 31a can be connected to the outside.

[0085] In this way, the deformation of the deformable portion 332b2 should be greater than the distance between the puncture portion 332b3 and one end of the deformable portion 332b2 and the sealing film 331b, so as to achieve directional pressure relief of the battery device when thermal runaway occurs.

[0086] Please refer to Figure 7 In some embodiments, the deformable portion 332b2 includes a deformable sheet, which includes a sheet main body portion 332b21 and a plurality of extension portions 332b22 provided on the sheet main body portion 332b21. The number of the fixed portions 332b1 is multiple, and each extension portion 332b22 is connected to the corresponding fixed portion 332b1. The puncture portion 332b3 is provided on the sheet main body portion 332b21.

[0087] As can be understood, in this embodiment, the deformable portion 332b2 is shaped like a petal. The main body of the deformable sheet is the portion that primarily deforms upon heating. Specifically, it deforms by convexing away from the center of each extension portion 332b22 toward the sealing membrane 331b. In this case, the puncture portion 332b3 should also be positioned at the center of the main body of the sheet to maximize the puncture stroke. The extension portion 332b22 is connected to the fixed portion 332b1 and can also deform upon heating, further increasing the overall deformation of the deformable sheet.

[0088] In this way, the main body 332b21 of the sheet is the main part that undergoes deformation in the deformable sheet, and the extension part 332b22 is the part of the deformable sheet that is connected to the fixed part 332b1. Then, when the main body 332b21 of the sheet is deformed by heat, under the action of the connection and fixation between the extension part 332b22 and the fixed part 332b1, the main body 332b21 of the sheet drives the puncture part 332b3 to move toward the sealing film 331b and destroy the sealing film 331b.

[0089] Please refer to Figure 8In some embodiments, the deformation portion 332b2 includes a spiral telescopic column, one end of the spiral telescopic column is disposed at the puncture portion 332b3, and the other end of the spiral telescopic column is connected to the fixing portion 332b1.

[0090] It can be understood that in this embodiment, the spiral telescopic cylinder is similar to a spring structure. Therefore, the spiral telescopic cylinder should have two oppositely arranged ends, one end of which is connected to the fixed portion 332b1, and this end is the fixed end, and the other end is connected to the puncture portion 332b3, and this end is the free end, which is also the end that protrudes toward the sealing membrane 331b relative to the fixed portion 332b1.

[0091] Similarly, when heated, the spiral telescopic cylinder as a whole extends along its own axial direction, thereby driving the puncture portion 332b3 to move toward the sealing film 331b and destroy the sealing film 331b.

[0092] Please refer to Figure 5 and Figure 6 In some embodiments, a cavity 31e connected to the second through hole 31a is provided on the base 31, and the cover 32 is covered in the cavity 31e. Moreover, the side wall of the cover 32 abuts against the inner wall of the cavity 31e, and at least one groove 31f is provided on the side wall of the cavity 31e, and the groove wall of the groove 31f is inclined.

[0093] As can be understood, cavity 31e accommodates cover plate 32, ensuring that the edge of cover plate 32 is surrounded by base 31 as much as possible, especially when the end surface of cover plate 32 is lower than or equal to the end surface of the base 31 outside cavity 31e. Groove 31f is used to increase the gap between the edge of cover plate 32 and the inner wall of cavity 31e to meet pressure relief requirements in the event of thermal runaway. Similarly, the inclined groove 31f also facilitates drainage.

[0094] In this way, when thermal runaway occurs in the battery device, pressure can be released through the groove 31 f . Furthermore, the groove 31 f with an inclined groove wall can also reduce the probability of water accumulation between the base 31 and the cover plate 32 .

[0095] Please refer to Figure 5 and Figure 6 In some embodiments, the pressure relief mechanism 30 includes a seal 35 , which is disposed between the base 31 and the outer wall of the box body 10 .

[0096] It is understandable that there is also a gap between the base 31 and the outer wall of the box body 10. Therefore, the sealing member 35 can improve the sealing performance of the connection between the base 31 and the outer wall of the box body 10. Here, the sealing member 35 should be arranged around the outer periphery of the first through hole 10b.

[0097] Please refer to Figures 4 to 8In a specific embodiment, the present application provides a battery device including a battery cell assembly, a housing 10, and a pressure relief mechanism 30. The pressure relief member 33 includes a sealing film 331b and a metal deformation member 332b. The sealing film 331b blocks the second through hole 31a. The metal deformation member 332b is disposed on the base 31 and spaced apart from the sealing film 331b. When heated, the metal deformation member 332b protrudes toward the sealing film 331b to destroy the sealing film 331b, thereby connecting the second through hole 31a to the outside. The metal deformable member 332b includes a fixed portion 332b1 connected to the base 31, a deformable portion 332b2 connected to the fixed portion 332b1, and a piercing portion 332b3 provided on the deformable portion 332b2. When heated, the deformable portion 332b2 protrudes toward the sealing membrane 331b. The piercing portion 332b3 pierces the sealing membrane 331b, thereby connecting the second through hole 31a to the outside. When heated, the deformable portion 332b2 protrudes toward the sealing membrane 331b by an amount greater than the distance N between the piercing portion 332b3 and the sealing membrane 331b, away from the end of the deformable portion 332b2.

[0098] The deformable portion 332b2 comprises a deformable sheet, which includes a sheet main portion 332b21 and multiple extensions 332b22 disposed on the sheet main portion 332b21. There are multiple fixed portions 332b1, each extension 332b22 connected to a corresponding fixed portion 332b1. The puncture portion 332b3 is disposed on the sheet main portion 332b21. Alternatively, the deformable portion 332b2 comprises a spiral telescopic cylinder, one end of which is disposed on the puncture portion 332b3, and the other end of which is connected to the fixed portion 332b1. The base 31 defines a cavity 31e that communicates with the second through hole 31a. The cover plate 32 is disposed within the cavity 31e, with the sidewalls of the cover plate 32 abutting against the inner wall of the cavity 31e. The sidewalls of the cavity 31e are defined by at least one groove 31f, the groove walls of which are inclined. A sealing member 35 is provided between the base 31 and the outer wall of the box body 10 .

[0099] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A battery device, characterized in that: include: A battery cell assembly, the battery cell assembly comprising a plurality of battery cells arranged in parallel; a box body having a housing space for housing the battery cell group; A pressure relief mechanism, wherein a first through hole communicating with the accommodating space is provided on an outer wall of the box body, the pressure relief mechanism is provided at the first through hole, the pressure relief mechanism comprising a base provided on the box body, a pressure relief member, and a cover provided on the base and covering the pressure relief member, the base being provided with a second through hole arranged opposite to the first through hole; The pressure relief member includes a sealing film and a metal deformation member, the sealing film blocks the second through hole, and the metal deformation member is provided on the base and spaced apart from the sealing film; the metal deformation member includes a fixed portion connected to the base, a deformable portion connected to the fixed portion, and a puncture portion provided on the deformable portion, the deformable portion protruding toward the sealing film when heated, and the deformable portion does not block the first through hole, and the puncture portion punctures the sealing film to achieve communication between the second through hole and the outside; The base is provided with a cavity connected to the second through hole, the cover plate is arranged in the cavity, and the side wall of the cover plate abuts against the inner wall of the cavity. The side wall of the cavity is provided with at least one groove, and the groove wall of the groove is inclined.

2. The battery device according to claim 1, wherein: When the deformable portion is heated, the amount of deformation of the deformable portion protruding toward the sealing film is greater than the distance from one end of the puncture portion away from the deformable portion to the sealing film.

3. The battery device according to claim 1, wherein: The deformable portion includes a deformable sheet, which includes a sheet body main body and multiple extension parts arranged on the sheet body main body. There are multiple fixing parts, each extension part is connected to the corresponding fixing part, and the puncture part is arranged on the sheet body main body.

4. The battery device according to claim 1, wherein: The deformation portion includes a spiral telescopic column, one end of the spiral telescopic column is arranged at the puncture portion, and the other end of the spiral telescopic column is connected to the fixing portion.

5. The battery device according to claim 1, wherein: The metal deformation piece is a thermal memory deformation metal.

6. The battery device according to claim 5, characterized in that The deformation part is a thermal memory deformation metal.

7. The battery device according to claim 6, characterized in that The thermosensitive memory deformation metal includes any one of a Ni-Ti based shape memory alloy, a Cu based shape memory alloy, a Ni-Mn based shape memory alloy, and a Fe based shape memory alloy.

8. The battery device according to any one of claims 1 to 7, characterized in that: The pressure relief mechanism includes a sealing member, which is arranged between the base and the outer wall of the box body.

9. An electrical device, characterized in that: Comprising the battery device according to any one of claims 1 to 8.

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