Battery device and electric device

Abstract

The invention provides a battery device and an electric device. The battery device comprises a box body, a cooling assembly and a battery module, the cooling assembly comprises a cooling plate and a working medium conveying pipeline. And the working medium conveying pipeline is communicated with the cooling plate. The working medium conveying pipeline is used for conveying cooling working media. The battery module is arranged in the box body. The battery module comprises a plurality of battery cells. The battery module is arranged on the cooling plate. And the cooling plate is used for heat exchange with the battery module. The battery cell includes a pressure relief mechanism. The working medium conveying pipeline comprises a first weak area. And the first weak area is arranged corresponding to the pressure relief mechanism of each battery monomer. The first weak area is configured to be broken to release the cooling working medium under the condition that the temperature reaches a first temperature threshold value T1. And the value range of the first temperature threshold value T1 is that T1 is more than 300 DEG C and less than 350 DEG C. The battery device provided by the invention is beneficial to improving the safety of the battery device.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development. Improving battery safety has always been a key research direction in battery technology development. Summary of the Invention

[0003] In view of the above problems, this application provides a battery device and an electrical device that can help improve the safety of the battery device.

[0004] This application provides a battery device, which includes a housing, a cooling assembly, and a battery module.

[0005] The cooling assembly includes a cooling plate and a working fluid delivery pipe. The working fluid delivery pipe is connected to the cooling plate and is used to deliver the cooling working fluid. The battery module is housed within the casing. The battery module includes multiple battery cells. The battery module is mounted on the cooling plate. The cooling plate is used for heat exchange with the battery module. Each battery cell includes a pressure relief mechanism. The working fluid delivery pipe includes a first weak point. The first weak point corresponds to the pressure relief mechanism of each battery cell. The first weak point is configured to rupture and release the cooling working fluid when the temperature reaches a first temperature threshold T1. The first temperature threshold T1 ranges from 300 degrees Celsius to 350 degrees Celsius.

[0006] In the battery device of this application embodiment, under normal operating conditions, the cooling component can cool the battery module. Even if a single battery cell experiences thermal runaway, the cooling component can still operate normally and cool the battery device. If multiple battery cells experience thermal runaway, the working fluid delivery pipe of the cooling component can rupture under the influence of these multiple runaway cells, releasing the cooling working fluid into the housing. The cooling working fluid can absorb heat and can change from a liquid to a gaseous state, achieving phase change cooling. This is beneficial for cooling the entire battery device, reducing the possibility of thermal runaway propagation leading to more battery cells experiencing thermal runaway, and improving the safety of the battery device.

[0007] In some feasible implementations, the pressure relief mechanism is positioned away from the cooling plate along the thickness direction of the cooling plate, and the orthographic projection of the first weak zone covers the orthographic projection of the pressure relief mechanism.

[0008] When the pressure relief mechanism discharges high-temperature, high-pressure substances, the first weak point of the working fluid transport pipeline is located in the path of the ejected high-temperature, high-pressure substances. The high-temperature, high-pressure substances discharged by the pressure relief mechanism can directly and rapidly act on the first weak point of the working fluid transport pipeline. The area affected by the high-temperature, high-pressure substances in the first weak point is relatively large, which is conducive to increasing the probability of rupture in the first weak point.

[0009] In some feasible implementations, an exhaust channel is formed between the housing and the battery module. The working fluid delivery pipe located in the exhaust channel has a second weak zone in a position that avoids the pressure relief mechanism. The second weak zone is configured to rupture to release the cooling working fluid when the temperature reaches a second temperature threshold T2. The value range of the second temperature threshold T2 is: 200 degrees Celsius < T2 < 250 degrees Celsius.

[0010] When a high-temperature, high-pressure substance is ejected after the pressure relief mechanism fails, the temperature of the substance is relatively higher in areas closer to the pressure relief mechanism and relatively lower in areas farther away. The second weak point of the working fluid delivery pipeline is located in the exhaust channel, away from the pressure relief mechanism. When the pressure relief mechanism discharges the high-temperature, high-pressure substance, the second weak point of the working fluid delivery pipeline is not located on the path of the ejected substance. Therefore, setting the second temperature threshold T2 of the working fluid delivery pipeline to 200°C < T2 < 250°C helps ensure that the high-temperature, high-pressure substance reaches the second temperature threshold T2 of the second weak point in a relatively short time after flowing into the exhaust channel. This increases the probability of the second weak point of the working fluid delivery pipeline rupturing, reduces the possibility that the high-temperature, high-pressure substance fails to rupture the second weak point after flowing into the exhaust channel, improves the response rate of the working fluid delivery pipeline, and enhances the safety of the battery device.

[0011] In some feasible implementations, the battery cell includes a housing and an end cap connected to the housing, a pressure relief mechanism is located on the end cap, and a second weak zone is located on the working fluid delivery pipe between the housing and the casing.

[0012] The working medium conveying pipeline can reuse the space between the shell and the container, which helps to improve the utilization rate of the internal space of the container.

[0013] In some feasible implementations, the pressure relief mechanism is positioned away from the cooling plate along the thickness direction of the cooling plate, and the orthographic projection of the second weak zone does not overlap with the orthographic projection of the battery module.

[0014] After the second weak zone of the working fluid delivery pipeline ruptures, the cooling working fluid discharged from the working fluid delivery pipeline can flow quickly along the exhaust channel between the battery module and the housing. This allows the cooling working fluid to come into contact with a larger number of battery cells in the battery module in a relatively short time, thereby cooling a larger number of battery cells.

[0015] When the pressure relief mechanism is damaged and ejects high-temperature and high-pressure substances, the cooling plate will not block the pressure relief mechanism. This reduces the possibility that the cooling plate will block the pressure relief mechanism, which would increase the resistance to the discharge of high-temperature and high-pressure substances. This is conducive to the timely and rapid discharge of high-temperature and high-pressure substances by the pressure relief mechanism, thereby improving the safety of the battery device.

[0016] In some feasible implementations, the battery device includes a pressure relief assembly disposed within the housing and used to connect the venting channel to the outside of the housing, with a second weak zone corresponding to the pressure relief assembly.

[0017] When the pressure relief assembly opens, high-temperature, high-pressure substances converge and are discharged towards the assembly area. These substances then act on the second weak point located within the assembly area, ensuring it reaches the rupture threshold and ruptures, thus increasing the probability of rupture in the second weak point. Simultaneously, the cooling medium discharged after the working fluid delivery pipe ruptures cools the high-temperature substances. When the cooled substances are discharged outside the casing, their hazard is reduced, thereby improving the safety of the battery device.

[0018] In some feasible implementations, there is a gap between the second weak zone and the pressure relief assembly, and the orthographic projection of the second weak zone onto the housing covers the pressure relief assembly.

[0019] The second weakest zone has a relatively large projected area on the enclosure. When the pressure relief assembly opens, high-temperature and high-pressure substances will converge and be discharged towards the pressure relief assembly area. The area affected by the high-temperature and high-pressure substances in the second weakest zone is relatively large, which helps to increase the probability of rupture in the second weakest zone.

[0020] In some feasible implementations, the pressure relief mechanism includes an explosion-proof valve, a balancing valve, a pneumatic valve, a pressure relief valve, or a safety valve, and the pressure relief assembly includes an explosion-proof valve, a balancing valve, a pneumatic valve, a pressure relief valve, or a safety valve.

[0021] In some feasible ways, the melting point of the material in the second weak zone ranges from 220 degrees Celsius to 235 degrees Celsius.

[0022] When the second weakest zone of the working medium transport pipeline is subjected to high temperature, the second weakest zone of the working medium transport pipeline is prone to melting and rupture.

[0023] In some feasible ways, the material of the second weak zone includes at least one of polybutylene terephthalate, polyamide, polyphenylene ether, and polycarbonate.

[0024] In some feasible ways, the melting point of the material in the first weak zone ranges from 310 degrees Celsius to 327 degrees Celsius.

[0025] When the first weakest point of a working medium transport pipeline is subjected to high temperature, the first weakest point of the pipeline is prone to melting and rupture.

[0026] In some feasible ways, the material of the first weak zone includes at least one of polyphthalamide, polyacrylonitrile, polyetheretherketone, and polytetrafluoroethylene.

[0027] This application provides an electrical device including the battery device described above. The battery device is used to provide electrical energy. Attached Figure Description

[0028] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0029] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0030] Figure 2 This is a partially exploded structural diagram of a battery device provided in an embodiment of this application;

[0031] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of the application;

[0032] Figure 4 This is a partially exploded structural diagram of a battery cell provided in an embodiment of this application;

[0033] Figure 5 This is a partial structural schematic diagram of a battery device provided in an embodiment of this application;

[0034] Figure 6 This is a partial cross-sectional view of a battery device provided in an embodiment of this application;

[0035] Figure 7 This is a partial structural schematic diagram of a battery device provided in an embodiment of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Vehicle; 10. Battery assembly; 10a. Housing; 10b. First housing section; 10c. Second housing section;

[0038] 11. Controller; 12. Motor;

[0039] 20. Battery module;

[0040] 30. Battery cell; 31. Pressure relief mechanism;

[0041] 40. End cap; 41. Electrode terminal;

[0042] 50. Shell;

[0043] 60. Electrode assembly;

[0044] 70. Cooling assembly; 71. Cooling plate; 72. Working fluid delivery pipeline; 721. First weak point; 722. Second weak point;

[0045] 80. Pressure relief assembly;

[0046] Z, thickness direction. Detailed Implementation

[0047] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0048] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0049] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0050] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0051] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0052] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery device applications, market demand is also constantly increasing.

[0054] In this application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto. The battery cell may be flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0055] The battery device mentioned in the embodiments of this application refers to a single physical module comprising multiple battery cells to provide higher voltage and capacity. The battery device mentioned in this application can be a battery pack. For example, the battery device mentioned in this application can include battery modules, etc. A battery device generally includes a housing for encapsulating multiple battery cells. The housing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0056] The inventors have noted that when a single battery cell in a battery device experiences thermal runaway, the runaway cell leads to an increase in internal pressure or temperature. If only a single battery cell experiences thermal runaway, the cooling components within the device can dissipate the heat generated by that cell, and the insulation components between the cells provide thermal insulation. Therefore, when only a single battery cell experiences thermal runaway, heat diffusion within the battery device is less likely to occur, and secondary disasters such as coolant leakage are less likely to result. However, if two or more battery cells experience thermal runaway, the heat generated by all the runaway cells is difficult to dissipate or insulate, potentially leading to overall combustion or explosion of the battery device, thus affecting its safety.

[0057] To alleviate the problem of heat dissipation and insulation from multiple thermally runaway battery cells, the applicant discovered that in the event of thermal runaway from multiple battery cells, heat can be absorbed and cooled down by releasing a cooling medium.

[0058] Based on the above considerations, the inventors, after in-depth research, designed a battery device. This battery device includes a cooling assembly. When a single battery cell does not experience thermal runaway, or when a single battery cell does experience thermal runaway, the cooling assembly functions normally to dissipate heat from the inside of the battery device. In the event of thermal runaway in multiple battery cells, the cooling assembly can release a cooling medium into the internal space of the battery device. The cooling medium absorbs heat and changes from a liquid to a gaseous state, thereby achieving phase change cooling. This is beneficial for cooling multiple thermally runaway battery cells, thus ensuring the safety of the battery device.

[0059] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0060] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. This application does not impose any special limitations on the above-mentioned electrical devices.

[0061] It should be understood that the technical solutions described in the embodiments of this application are not limited to the battery devices and electrical devices described above, but can also be applied to all battery devices including housings and electrical devices using battery devices. However, for the sake of brevity, the following embodiments are all illustrated using electric vehicles as examples.

[0062] Figure 1 The structure of vehicle 1 is shown schematically. See also Figure 1 As shown, vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 10 is installed inside vehicle 1. The battery device 10 can be located at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1. For example, the battery device 10 can serve as the operating power source for vehicle 1. Vehicle 1 may also include a controller 11 and a motor 12. The controller 11 is used to control the battery device 10 to supply power to the motor 12. For example, this is for the power needs of vehicle 1 during starting, navigation, and driving.

[0063] In some embodiments of this application, the battery device 10 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1.

[0064] To meet different power demands, the battery device 10 may include multiple battery cells. A battery cell is the smallest unit that makes up a battery module or battery pack. Multiple battery cells can be connected in series and / or in parallel via electrode terminals for various applications. The battery device mentioned in this application includes a battery module or battery pack. Multiple battery cells can be connected in series, parallel, or a combination thereof. A combination thereof refers to a mix of series and parallel connections. In the embodiments of this application, multiple battery cells can be directly assembled into a battery pack, or they can first be assembled into a battery module, and then the battery modules can be assembled into a battery pack.

[0065] Figure 2 A partial exploded view of the battery assembly 10 is schematically shown. See also... Figure 2 As shown, the battery device 10 includes a housing 10a and individual battery cells (not shown). The individual battery cells are housed within the housing 10a.

[0066] The housing 10a can be a simple three-dimensional structure such as a single cuboid, cylinder, or sphere, or it can be a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders, or spheres. This application embodiment does not limit this. The material of the housing 10a can be an alloy material such as aluminum alloy or iron alloy, or a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin. This application embodiment also does not limit this.

[0067] The housing 10a is used to accommodate individual battery cells, and the housing 10a can have various structures. In some embodiments, the housing 10a may include a first housing portion 10b and a second housing portion 10c. The first housing portion 10b and the second housing portion 10c overlap each other. The first housing portion 10b and the second housing portion 10c together define a receiving space for accommodating the individual battery cells. The second housing portion 10c may be a hollow structure with one open end. In some embodiments, the first housing portion 10b is a plate-like structure. The first housing portion 10b overlaps the open side of the second housing portion 10c to form a housing 10a with a receiving space. In some embodiments, both the first housing portion 10b and the second housing portion 10c may also be hollow structures with one open side. The open side of the first housing portion 10b overlaps the open side of the second housing portion 10c to form a housing 10a with a receiving space. Of course, the first housing portion 10b and the second housing portion 10c can have various shapes, such as cylinders, cuboids, etc.

[0068] To improve the sealing performance after the first housing part 10b and the second housing part 10c are connected, a sealing element, such as sealant or sealing ring, can also be provided between the first housing part 10b and the second housing part 10c.

[0069] In some embodiments, the first housing portion 10b covers the top of the second housing portion 10c. The first housing portion 10b may also be referred to as the upper housing cover, and the second housing portion 10c may also be referred to as the lower housing.

[0070] In the battery device 10, there can be multiple battery cells. When there are multiple battery cells, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells are connected in both series and parallel. Multiple battery cells can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells is housed within the housing 10a. Of course, multiple battery cells can also be first connected in series, parallel, or in a mixed configuration to form a battery module. Multiple battery modules are then connected in series, parallel, or in a mixed configuration to form a whole, and housed within the housing 10a.

[0071] In some embodiments, Figure 3 The structure of battery module 20 is shown schematically. See also Figure 3 As shown, there can be multiple battery cells 30. Multiple battery cells 30 are first connected in series, parallel, or in a mixed connection to form a battery module 20. Multiple battery modules 20 are then connected in series, parallel, or in a mixed connection to form a whole, which is housed in the casing 10a.

[0072] Multiple battery cells 30 in the battery module 20 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 30 in the battery module 20.

[0073] In this embodiment, the battery cell 30 may include a lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and this embodiment is not limited thereto. The battery cell 30 may be flat, cuboid, or other shapes, and this embodiment is not limited thereto either. However, for the sake of brevity, the following embodiment uses a cuboid battery cell 30 as an example for illustration.

[0074] Figure 4 The diagram schematically shows a partially disassembled structure of the battery cell 30. The battery cell 30 refers to the smallest unit comprising the battery assembly 10. See also... Figure 4 As shown, the battery cell 30 includes an end cap 40, a housing 50, and an electrode assembly 60.

[0075] End cap 40 refers to a component that covers the opening of housing 50 to isolate the internal environment of battery cell 30 from the external environment. Exemplarily, the shape of end cap 40 can be adapted to the shape of housing 50 to fit the housing 50. Exemplarily, end cap 40 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 40 is not easily deformed under pressure or impact, enabling battery cell 30 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 41 can be provided on end cap 40. Electrode terminals 41 can be used for electrical connection with electrode assembly 60 for outputting or inputting electrical energy into battery cell 30.

[0076] In some embodiments, the end cap 40 may also be provided with a pressure relief mechanism 31 for releasing internal pressure when the internal pressure or temperature of the battery cell 30 reaches a threshold. The end cap 40 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating component may also be provided on the inner side of the end cap 40. The insulating component can be used to isolate the electrical connection components within the housing 50 from the end cap 40 to reduce the risk of short circuits. Exemplarily, the insulating component can be plastic, rubber, etc.

[0077] The housing 50 is a component used to cooperate with the end cap 40 to form the internal environment of the battery cell 30. The formed internal environment can accommodate the electrode assembly 60, electrolyte (not shown in the figure), and other components. The housing 50 and the end cap 40 can be independent components. An opening can be provided on the housing 50, and the end cap 40 closes the opening to form the internal environment of the battery cell 30. Alternatively, the end cap 40 and the housing 50 can be integrated. Specifically, the end cap 40 and the housing 50 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 50, the end cap 40 closes the housing 50. The housing 50 can be of various shapes and sizes, such as cuboid, hexagonal prism, etc. Specifically, the shape of the housing 50 can be determined according to the specific shape and size of the electrode assembly 60. The material of the housing 50 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment does not impose any special limitations on this.

[0078] In some embodiments, a pressure relief mechanism 31 is provided on the casing of the battery cell 30. The pressure relief mechanism 31 is used to release the internal pressure of the battery cell 30. In some examples, the casing of the battery cell 30 may include an end cap 40 and a housing 50. The pressure relief mechanism 31 is provided on the end cap 40.

[0079] As an example, the internal pressure or temperature of the battery cell 30 is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 30 reaches the predetermined threshold, the pressure relief mechanism 31 is activated or a weak structure provided in the pressure relief mechanism 31 is destroyed, thereby forming an opening or channel for the internal pressure or temperature to be released. The threshold design varies depending on the design requirements. The threshold may depend on one or more of the materials of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 30.

[0080] As an example, the pressure relief mechanism 31 can be integrally formed with the housing, for example, by creating grooves on the housing to form a weak structure, which serves as the pressure relief mechanism 31.

[0081] The pressure relief mechanism 31 can also be separately disposed from and connected to the housing, for example, by welding it to the housing or by connecting it through other components. As an example, the pressure relief mechanism 31 is provided with grooves to form a weak structure.

[0082] As an example, the pressure relief mechanism 31 may include valves such as explosion-proof valves, balance valves, air valves, pressure relief valves, or safety valves.

[0083] The term "actuation" as used in this application refers to the pressure relief mechanism 31 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 30. The actions of the pressure relief mechanism 31 may include, but are not limited to: movement of components within the pressure relief mechanism 31 to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism 31, etc. When the pressure relief mechanism 31 is actuated, the high-temperature, high-pressure substances inside the battery cell 30 are discharged outwards from the actuated portion as waste. This method allows for pressure and temperature relief of the battery cell 30 under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0084] The emissions from the battery cell 30 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of the separator, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0085] Figure 5 A partial structure of the battery device 10 is shown schematically. Figure 6 A partial cross-sectional view of the battery device 10 is shown schematically. Figure 7 A partial structure of the battery device 10 is shown schematically. See also Figure 2 , Figure 5 , Figure 6 and Figure 7 As shown, this application embodiment provides a battery device 10, which includes a housing 10a, a cooling assembly 70, and a battery module 20. The cooling assembly 70 includes a cooling plate 71 and a working fluid delivery pipe 72. The working fluid delivery pipe 72 is connected to the cooling plate 71 and is used to deliver the cooling working fluid. The battery module 20 is disposed within the housing 10a. The battery module 20 includes multiple battery cells 30. The battery module 20 is disposed on the cooling plate 71. The cooling plate 71 is used for heat exchange with the battery module 20. Each battery cell 30 includes a pressure relief mechanism 31. The working fluid delivery pipe 72 includes a first weak zone 721. The first weak zone 721 is provided corresponding to the pressure relief mechanism 31 of each battery cell 30. The first weak zone 721 is configured to rupture to release the cooling working fluid when the temperature reaches a first temperature threshold T1. The first temperature threshold T1 ranges from 300 degrees Celsius to 350 degrees Celsius.

[0086] In this embodiment, under normal operating conditions, the individual battery cells 30 in the battery module 20 generate heat. During normal operation, the cooling plate 71 of the cooling assembly 70 can exchange heat with the battery module 20 to cool it and prevent overheating. The working fluid delivery pipe 72 is used to deliver a cooling working fluid to the cooling plate 71. The cooling working fluid flows within the cooling plate 71 and absorbs heat from the battery module 20 to cool it. The cooling working fluid can be a liquid coolant. For example, it can include ultrapure water or a fluorinated liquid.

[0087] When a single battery cell 30 experiences thermal runaway, its temperature rises, and it can release high-temperature, high-pressure material into the housing 10a to depressurize. During this depressurization, the high-temperature, high-pressure material generates an impact force, which can also raise the temperature within the housing 10a. The impact or temperature rise from a single thermally runaway battery cell 30 is relatively small, allowing the cooling assembly 70 to function normally and cool the space within the housing 10a and the battery module 20. Therefore, a single thermally runaway battery cell 30 will not trigger the rupture threshold of the working fluid delivery pipe 72. The working fluid delivery pipe 72 can then normally deliver cooling fluid to the cooling plate 71.

[0088] When multiple thermal runaway battery cells 30 occur, the impact or temperature rise generated by these cells is relatively large, potentially triggering a first temperature threshold T1 in the working fluid delivery pipe 72, causing the first weak point 721 of the pipe to rupture. The rupture of the pipe releases the cooling working fluid, which absorbs heat from the thermal runaway battery cells 30. Simultaneously, the cooling working fluid absorbs heat and changes from a liquid to a gaseous state, achieving phase change cooling, which is beneficial for cooling the multiple thermal runaway battery cells 30.

[0089] Multiple battery cells 30 can experience thermal runaway simultaneously or at different times. At different times, multiple battery cells 30 can experience thermal runaway sequentially at intervals.

[0090] In the battery device 10 of this application embodiment, under normal operating conditions, the cooling component 70 can cool the battery module 20. Even if a single battery cell 30 in the battery device 10 experiences thermal runaway, the cooling component 70 can still operate normally and cool the battery device 10. If multiple battery cells 30 in the battery device 10 experience thermal runaway, the working fluid delivery pipe 72 of the cooling component 70 can rupture under the influence of the multiple thermally runaway battery cells 30, releasing the cooling working fluid into the housing 10a. The cooling working fluid can absorb heat and can change from a liquid to a gaseous state, thereby achieving phase change cooling. This is beneficial for cooling the entire battery device 10, reducing the possibility of thermal runaway propagation leading to thermal runaway in more battery cells 30, and improving the safety of the battery device 10.

[0091] In some feasible implementations, when N battery cells 30 experience thermal runaway, the temperature of the first weak zone 721 of the working fluid delivery pipe 72 reaches a first temperature threshold T1. N is a positive integer greater than or equal to 2.

[0092] Under the influence of the high-temperature substances released by the thermal runaway of battery cell 30, the temperature inside the housing 10a rises. The temperature rise within the housing 10a caused by a single thermal runaway battery cell 30 is relatively small, allowing the cooling assembly 70 to operate normally and cool the space within the housing 10a and the battery module 20. A single thermal runaway battery cell 30 will not trigger the first temperature threshold T1 of the working fluid delivery pipe 72. The working fluid delivery pipe 72 can then normally deliver cooling working fluid to the cooling plate 71.

[0093] The temperature rise within the housing 10a caused by multiple thermal runaway battery cells 30 is relatively large, thus triggering the first temperature threshold T1 of the working fluid delivery pipe 72. The first weak point 721 of the working fluid delivery pipe 72 ruptures to release the cooling working fluid. The cooling working fluid can absorb heat from the thermal runaway battery cells 30. Simultaneously, the cooling working fluid can absorb heat and change from a liquid to a gaseous state, thereby achieving phase change cooling, which is beneficial for cooling down the multiple thermal runaway battery cells 30.

[0094] See Figures 5 to 7 As shown, the battery cell 30 includes a pressure relief mechanism 31. When thermal runaway occurs in the battery cell 30, the internal pressure or temperature of the battery cell 30 increases. When the internal pressure or temperature of the battery cell 30 reaches a predetermined threshold of the pressure relief mechanism 31, the pressure relief mechanism 31 is destroyed, thereby forming an opening or channel for the internal pressure or temperature to be released, and the high-temperature and high-pressure material inside the battery cell 30 is discharged outward as a discharge from the opening or channel. The closer to the pressure relief mechanism 31, the higher the temperature of the high-temperature and high-pressure material.

[0095] The first weak point 721 of the working fluid delivery pipe 72 is located on one side of the pressure relief mechanism 31. When the pressure relief mechanism 31 discharges high-temperature and high-pressure substances, the first weak point 721 of the working fluid delivery pipe 72 is located in the path of the high-temperature and high-pressure substances. The high-temperature and high-pressure substances discharged by the pressure relief mechanism 31 can directly and rapidly act on the first weak point 721 of the working fluid delivery pipe 72. When multiple battery cells 30 experience thermal runaway, the response time for the rupture of the first weak point 721 of the working fluid delivery pipe 72 can be relatively shorter, which is beneficial to improving the response rate of the first weak point 721 of the working fluid delivery pipe 72 and improving the safety of the battery device 10.

[0096] The first temperature threshold T1 ranges from 300 degrees Celsius (°C) to 350 degrees Celsius. Under the influence of the high-temperature substances released by the thermal runaway of the battery cell 30, the temperature inside the housing 10a rises. The temperature rise inside the housing 10a caused by a single thermally runaway battery cell 30 is relatively small. For example, a single thermally runaway battery cell 30 can raise the temperature inside the housing 10a to 130 to 180 degrees Celsius. Therefore, when a single battery cell 30 experiences thermal runaway, the temperature inside the housing 10a is below the first temperature threshold T1 of the working fluid delivery pipe 72. A single thermally runaway battery cell 30 will not trigger the first temperature threshold T1 of the working fluid delivery pipe 72. The working fluid delivery pipe 72 can normally deliver cooling working fluid to the cooling plate 71.

[0097] The temperature rise within the housing 10a caused by two thermal runaway battery cells 30 is relatively large. Two thermal runaway battery cells 30 can raise the temperature within the housing 10a to 320 to 400 degrees Celsius. Therefore, when two battery cells 30 experience thermal runaway, the temperature within the housing 10a exceeds the first temperature threshold T1 of the working fluid delivery pipe 72. Two thermal runaway battery cells 30 can trigger the first temperature threshold T1 of the working fluid delivery pipe 72. Three or more thermal runaway battery cells 30 can cause the temperature within the housing 10a to rise even higher. Therefore, three or more thermal runaway battery cells 30 can also trigger the first temperature threshold T1 of the working fluid delivery pipe 72.

[0098] The setting of the first temperature threshold T1 of the working fluid delivery pipeline 72 as 300 degrees Celsius (°C) < T1 < 350 degrees Celsius can help ensure that when two or more battery cells 30 experience thermal runaway, the first weak area 721 corresponding to the pressure relief mechanism 31 can rupture in time, which helps to improve the response rate of the working fluid delivery pipeline 72 and improve the safety of the battery device 10.

[0099] In some feasible implementations, the melting point of the material of the first weak region 721 ranges from 310°C to 327°C. When the first weak region 721 of the working fluid transport pipe 72 is subjected to high temperatures, it is prone to melting and rupture. In some examples, the material of the first weak region 721 includes at least one of polyphthalamide (PPA), polyacrylonitrile (PAN), polyetheretherketone (PEEK), and polytetrafluoroethylene (PTFE). The melting point of polyphthalamide is 310°C. The melting point of polyacrylonitrile is 320°C. The melting point of polyetheretherketone is 335°C. The melting point of polytetrafluoroethylene is 327°C.

[0100] In some feasible implementations, a gap exists between the first weak point 721 of the working fluid delivery pipe 72 and the pressure relief mechanism 31. The high-temperature and high-pressure substances discharged by the pressure relief mechanism 31 can pass through the gap between the working fluid delivery pipe 72 and the pressure relief mechanism 31, reducing the possibility that the working fluid delivery pipe 72 may obstruct the pressure relief mechanism 31, resulting in greater resistance to the discharge of high-temperature and high-pressure substances.

[0101] In some feasible ways, the pressure relief mechanism 31 is positioned away from the cooling plate 71 along the thickness direction Z of the cooling plate 71, and the orthographic projection of the first weak area 721 covers the orthographic projection of the pressure relief mechanism 31.

[0102] When the pressure relief mechanism 31 discharges high-temperature and high-pressure substances, the first weak zone 721 of the working medium conveying pipeline 72 is located in the path of the high-temperature and high-pressure substances. The high-temperature and high-pressure substances discharged by the pressure relief mechanism 31 can directly and rapidly act on the first weak zone 721 of the working medium conveying pipeline 72. The area of ​​the high-temperature and high-pressure substances acting on the first weak zone 721 is relatively large, which is conducive to increasing the probability of rupture of the first weak zone 721.

[0103] See also some of the possible implementation methods. Figure 6 and Figure 7 As shown, the battery cell 30 includes a pressure relief mechanism 31. An exhaust channel is formed between the housing 10a and the battery module 20. A working fluid delivery pipe 72 located within the exhaust channel has a second weak zone 722 positioned away from the pressure relief mechanism 31. The second weak zone 722 is configured to rupture and release the cooling working fluid when the temperature reaches a second temperature threshold T2. The second temperature threshold T2 ranges from 200 degrees Celsius to 250 degrees Celsius.

[0104] The second weak zone 722 of the working fluid conveying pipeline 72 is located in the exhaust channel away from the pressure relief mechanism 31. When the pressure relief mechanism 31 discharges high-temperature and high-pressure substances, the second weak zone 722 of the working fluid conveying pipeline 72 is not located in the path of the high-temperature and high-pressure substances. After the high-temperature and high-pressure substances discharged by the pressure relief mechanism 31 flow into the exhaust channel, they come into contact with the second weak zone 722 of the working fluid conveying pipeline 72, and the high-temperature and high-pressure substances can sweep across the second weak zone 722 of the working fluid conveying pipeline 72.

[0105] When the pressure relief mechanism 31 is damaged and ejects high-temperature and high-pressure substances, the temperature of the high-temperature and high-pressure substances is relatively higher in areas closer to the pressure relief mechanism 31, and relatively lower in areas farther away from the pressure relief mechanism 31. The second weak zone 722 of the working fluid delivery pipe 72 is located in the exhaust channel away from the pressure relief mechanism 31. When the pressure relief mechanism 31 discharges high-temperature and high-pressure substances, the second weak zone 722 of the working fluid delivery pipe 72 is not located on the path of the high-temperature and high-pressure substances. Therefore, the second temperature threshold T2 of the working fluid delivery pipe 72 being 200 degrees Celsius < T2 < 250 degrees Celsius helps to ensure that after the high-temperature and high-pressure substances flow into the exhaust channel, they can reach the second temperature threshold T2 of the second weak zone 722 in a relatively short time under the action of the high-temperature and high-pressure substances, increasing the probability of the second weak zone 722 of the working fluid delivery pipe 72 rupturing, reducing the possibility that the second weak zone 722 of the working fluid delivery pipe 72 fails to rupture after flowing into the exhaust channel, improving the response rate of the working fluid delivery pipe 72, and improving the safety of the battery device 10.

[0106] In some feasible implementations, when multiple battery cells 30 experience thermal runaway simultaneously, the pressure relief mechanisms 31 of the multiple battery cells 30 simultaneously release high-temperature, high-pressure substances, thereby causing the temperature inside the housing 10a to rise within a relatively short period of time. Alternatively, the multiple battery cells 30 do not experience thermal runaway simultaneously, but rather experience thermal runaway sequentially at time intervals. The temperature inside the housing 10a continuously increases as the number of thermally runaway battery cells 30 increases.

[0107] The first weak zone 721 of the working fluid delivery pipe 72 is provided corresponding to the pressure relief mechanism 31 of each battery cell 30, and the second weak zone 722 of the working fluid delivery pipe 72 is provided in the exhaust channel away from the pressure relief mechanism 31. When multiple battery cells 30 experience thermal runaway, at least one of the first weak zone 721 and the second weak zone 722 of the working fluid delivery pipe 72 can rupture, allowing the working fluid delivery pipe 72 to release the cooling working fluid. The arrangement of the first weak zone 721 and the second weak zone 722 in different areas of the working fluid delivery pipe 72 increases the probability of rupture of the working fluid delivery pipe 72 when multiple battery cells 30 experience thermal runaway. For example, the number of first weak zones 721 in the working fluid delivery pipe 72 can be one or more. The number of second weak zones 722 in the working fluid delivery pipe 72 can be one or more.

[0108] In some feasible implementations, the melting point of the material of the second weak region 722 ranges from 220°C to 235°C. When the second weak region 722 of the working fluid transport pipe 72 is subjected to high temperatures, it is prone to melting and rupture. In some examples, the material of the second weak region 722 may include at least one of polybutylene terephthalate (PBT), polyamide (PA), polyphenylene ether (PPE), and polycarbonate (PC). Polyamide may include polyamide 6 (PA6) or polyamide 610 (PA610). The melting point of polybutylene terephthalate can be 220°C. The melting point of polyamide 6 can be between 220°C and 230°C. The melting point of polyamide 610 can be 226°C. The melting point of polyphenylene ether can be 230°C. The melting point of polycarbonate can be 235°C.

[0109] In some examples, the battery cell 30 includes a housing 50 and an end cap 40. The end cap 40 is connected to the housing 50. A pressure relief mechanism 31 is disposed on the end cap 40. A second weak zone 722 is disposed on the working fluid delivery pipe 72 between the housing 50 and the casing 10a. An exhaust channel can be formed between the housing 50 and the casing 10a.

[0110] The working medium conveying pipeline 72 can reuse the space between the shell 50 and the box 10a, which is beneficial to improving the utilization rate of the internal space of the box 10a.

[0111] In some examples, the pressure relief mechanism 31 is positioned away from the cooling plate 71 along the thickness direction Z of the cooling plate 71. The orthographic projection of the second weak zone 722 of the working fluid delivery pipe 72 does not overlap with the orthographic projection of the battery module 20. The second weak zone 722 of the working fluid delivery pipe 72 is located on the periphery of the battery module 20.

[0112] After the second weak zone 722 of the working fluid delivery pipe 72 ruptures, the cooling working fluid discharged from the working fluid delivery pipe 72 can flow quickly along the exhaust channel between the battery module 20 and the housing 10a, which is conducive to the cooling working fluid contacting a large number of battery cells 30 in the battery module 20 in a relatively short time, so as to cool down a large number of battery cells 30.

[0113] When the pressure relief mechanism 31 is damaged and ejects high-temperature and high-pressure substances, the cooling plate 71 will not block the pressure relief mechanism 31, reducing the possibility that the cooling plate 71 will block the pressure relief mechanism 31 and cause an increase in the resistance to discharge of high-temperature and high-pressure substances. This is conducive to the timely and rapid discharge of high-temperature and high-pressure substances by the pressure relief mechanism 31, and improves the safety of the battery device 10.

[0114] See in some examples Figure 6 As shown, the battery device 10 includes a pressure relief assembly 80. The pressure relief assembly 80 is disposed in the housing 10a and is used to connect the venting channel and the outside of the housing 10a. A second weak point 722 of the working fluid delivery pipe 72 is disposed corresponding to the pressure relief assembly 80.

[0115] When a single battery cell 30 experiences thermal runaway, the internal pressure or temperature of the housing 10a increases. When the internal pressure or temperature of the housing 10a reaches a predetermined threshold of the pressure relief mechanism 31, the pressure relief assembly 80 malfunctions, thereby creating an opening or channel for releasing internal pressure or temperature. The high-temperature, high-pressure substances released by the single battery cell 30 are discharged as emissions from the opening or channel to the outside of the housing 10a. After the pressure relief assembly 80 malfunctions, it connects the exhaust channel to the outside of the housing 10a.

[0116] When the pressure relief assembly 80 is opened, the high-temperature and high-pressure material will converge and be discharged towards the area of ​​the pressure relief assembly 80. This high-temperature and high-pressure material will then act on the second weak zone 722 located within the pressure relief assembly 80 area, ensuring that the second weak zone 722 reaches the rupture threshold and ruptures, thus increasing the probability of rupture of the second weak zone 722. Simultaneously, the cooling working fluid discharged after the working fluid delivery pipe 72 ruptures can cool the high-temperature material. When the cooled material is discharged outside the housing 10a, its hazard level is reduced, thereby improving the safety of the battery device 10.

[0117] For example, the pressure relief assembly 80 may include valves such as explosion-proof valves, balance valves, air valves, pressure relief valves, or safety valves.

[0118] In some examples, there is a gap between the second weak zone 722 and the pressure relief assembly 80. The orthographic projection of the second weak zone 722 onto the housing 10a covers the pressure relief assembly 80.

[0119] The area of ​​the second weak zone 722 projected onto the housing 10a is relatively large. When the pressure relief assembly 80 is opened, high-temperature and high-pressure substances will converge and be discharged towards the area of ​​the pressure relief assembly 80. The area of ​​the high-temperature and high-pressure substances acting on the second weak zone 722 is relatively large, which is conducive to increasing the probability of the second weak zone 722 rupture.

[0120] According to some embodiments of this application, this application also provides an electrical device including a battery device 10 of any of the above schemes, and the battery device 10 is used to provide electrical energy to the electrical device.

[0121] The power supply device can be any of the aforementioned devices or systems that utilize battery device 10.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery device, characterized in that, include: Box; A cooling assembly includes a cooling plate and a working fluid delivery pipe, wherein the working fluid delivery pipe is connected to the cooling plate and is used to deliver a cooling working fluid. A battery module is disposed within the housing, the battery module comprising multiple battery cells, the battery module being disposed on the cooling plate, the cooling plate being used for heat exchange with the battery module; each battery cell includes a pressure relief mechanism. The working fluid transport pipeline includes a first weak zone, which is provided in accordance with the pressure relief mechanism of each battery cell. The first weak zone is configured to rupture to release the cooling working fluid when the temperature reaches a first temperature threshold T1. The first temperature threshold T1 is in the range of 300 degrees Celsius < T1 < 350 degrees Celsius.

2. The battery device according to claim 1, characterized in that, Along the thickness direction of the cooling plate, the pressure relief mechanism is disposed away from the cooling plate, and the orthographic projection of the first weak area covers the orthographic projection of the pressure relief mechanism.

3. The battery device according to claim 1 or 2, characterized in that, An exhaust channel is formed between the housing and the battery module. The working fluid delivery pipe located in the exhaust channel has a second weak zone in a position that avoids the pressure relief mechanism. The second weak zone is configured to rupture to release the cooling working fluid when the temperature reaches a second temperature threshold T2. The value range of the second temperature threshold T2 is: 200 degrees Celsius < T2 < 250 degrees Celsius.

4. The battery device according to claim 3, characterized in that, The battery cell includes a housing and an end cap, the end cap being connected to the housing, the pressure relief mechanism being disposed on the end cap, and the second weak area being disposed on the working fluid delivery pipeline between the housing and the casing.

5. The battery device according to claim 4, characterized in that, Along the thickness direction of the cooling plate, the pressure relief mechanism is disposed away from the cooling plate, and the orthographic projection of the second weak area does not overlap with the orthographic projection of the battery module.

6. The battery device according to claim 4 or 5, characterized in that, The battery device includes a pressure relief assembly, which is disposed in the housing and used to connect the exhaust channel and the outside of the housing. The second weak area is disposed corresponding to the pressure relief assembly.

7. The battery device according to claim 6, characterized in that, There is a gap between the second weak area and the pressure relief assembly, and the orthographic projection of the second weak area on the housing covers the pressure relief assembly.

8. The battery device according to claim 6 or 7, characterized in that, The pressure relief mechanism includes an explosion-proof valve, a balance valve, a gas valve, a pressure relief valve, or a safety valve, and the pressure relief assembly includes an explosion-proof valve, a balance valve, a gas valve, a pressure relief valve, or a safety valve.

9. The battery device according to any one of claims 3 to 8, characterized in that, The melting point of the material in the second weak zone ranges from 220 degrees Celsius to 235 degrees Celsius.

10. The battery device according to claim 9, characterized in that, The material of the second weak region includes at least one of polybutylene terephthalate, polyamide, polyphenylene ether, and polycarbonate.

11. The battery device according to any one of claims 1 to 10, characterized in that, The melting point of the material in the first weak zone ranges from 310 degrees Celsius to 327 degrees Celsius.

12. The battery device according to claim 11, characterized in that, The material of the first weak region includes at least one of polyphthalamide, polyacrylonitrile, polyetheretherketone, and polytetrafluoroethylene.

13. An electrical appliance, characterized in that, Includes the battery device as described in any one of claims 1 to 12, the battery device being used to provide electrical energy.

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