Pressure release valve and battery pack

Abstract

The embodiment of the invention provides a pressure release valve and a battery pack, and relates to the field of energy storage. The pressure release valve comprises a valve body, a movable assembly and at least one cooling piece. An exhaust channel is arranged in the valve body, and two ends of the exhaust channel are respectively an inlet and a valve port. The inlet is used for being in butt joint with a cavity to be decompressed, and the movable assembly is movably arranged at the valve port. The movable assembly seals the valve port when the air pressure in the exhaust channel is smaller than an exhaust threshold value, and the movable assembly is pushed away by smoke in the exhaust channel to expose the valve port when the air pressure in the exhaust channel reaches the exhaust threshold value. The cooling piece is made of a phase change material, and the cooling piece is installed in the exhaust channel and located on the flowing path of the flue gas so as to cool the flue gas flowing through the exhaust channel. According to the pressure release valve and the battery pack, the cooling piece can cool the flue gas when the flue gas is discharged, and the safety is higher when the pressure release valve discharges the flue gas for pressure release.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of energy storage, and specifically to a pressure relief valve and a battery pack. Background Art

[0002] With the continuous development of energy storage technology, battery packs are increasingly used in electric vehicles, portable computing devices and other electrical equipment. During the charging and discharging process of the battery pack, the battery cells in the battery pack will produce chemical reactions, generating heat and smoke. If the air pressure inside the battery pack is too high, the high-pressure smoke will break through the battery pack shell and cause an explosion. Therefore, timely pressure relief has become a key means to ensure the safety of the battery pack.

[0003] Existing battery packs are usually provided with a pressure relief valve, which is closed when the air pressure inside the battery pack is normal, and opens when the air pressure inside the battery pack is too high, thereby releasing the air pressure inside the battery pack in time to avoid explosion or fire of the battery pack.

[0004] However, the flue gas discharged by the pressure relief valve has a high temperature and is easily ignited when discharged at a high speed, causing an open flame at the location of the pressure relief valve, which poses a certain safety risk. Therefore, how to improve the safety of flue gas discharge has become a technical problem to be solved. Summary of the invention

[0005] In view of the above problems, the embodiment of the present application provides a pressure relief valve, in which a cooling element made of phase change material is provided in the exhaust channel of the pressure relief valve, and the cooling element is located on the flow path of the smoke when it is discharged, which can cool the smoke when it is discharged, so that the temperature of the smoke is lower than the ignition point, thereby preventing the smoke from being ignited when it is discharged at a high speed, and the smoke is safer when discharged through the pressure relief valve. The embodiment of the present application also provides a battery pack provided with the pressure relief valve.

[0006] According to one aspect of an embodiment of the present application, a pressure relief valve is provided, which includes a valve body, a movable component and at least one cooling component. An exhaust channel is provided in the valve body, and the two ends of the exhaust channel are an inlet and a valve port, respectively. The inlet is used to dock with the chamber to be depressurized, and the movable component is movably arranged at the valve port. The movable component closes the valve port when the air pressure in the exhaust channel is less than the exhaust threshold, and the movable component is pushed open by the flue gas in the exhaust channel to expose the valve port when the air pressure in the exhaust channel reaches the exhaust threshold. The cooling component adopts a phase change material, and the cooling component is installed in the exhaust channel and is located on the flow path of the flue gas to cool the flue gas flowing through the exhaust channel.

[0007] This type of pressure relief valve can provide reliable pressure relief while cooling the flue gas by using a cooling element made of phase change material, so that the flue gas discharged during pressure relief is kept at a low temperature when passing through the pressure relief valve, thereby preventing the flue gas from being ignited during high-speed discharge. The flue gas is safer when discharged through the pressure relief valve.

[0008] In an optional manner, a plurality of cooling elements are arranged at the inlet along a direction from the inlet to the valve port to cool the flue gas at the inlet.

[0009] In this method, a plurality of cooling components are arranged at the entrance of the exhaust passage, which can cool the smoke in the pressure relief chamber when the smoke enters the exhaust passage. The cooling effect is better and it can ensure that the smoke entering the exhaust passage is low-temperature smoke, so that the smoke is not easy to catch fire when discharged at a high speed.

[0010] In an optional manner, the movable component includes an elastic member and a movable member, and the movable member is movably arranged at the valve port. When the air pressure in the exhaust channel is less than the exhaust threshold, the movable member closes the valve port under the elastic force of the elastic member. When the air pressure in the exhaust channel reaches the exhaust threshold, the movable member is pushed open by the smoke in the exhaust channel to expose the valve port.

[0011] In this manner, the elastic member and the movable member cooperate to realize the closing and opening of the valve port, and the structure is simple, the action is reliable, and the assembly and debugging are convenient.

[0012] In an optional manner, the elastic member is a spring. The movable member includes a valve cover, a valve stem and a stopper. The valve cover and the stopper are located at opposite ends of the valve stem, and the valve stem passes through the valve port so that the stopper is located in the exhaust passage. The spring is arranged between the stopper and the valve body so that the valve cover can close the valve port under the elastic force of the spring.

[0013] In this method, the elastic member is set as a spring, and the movable member and the valve port form a piston structure. The movable member moves in a simple linear motion, requires a small space for movement, has a compact overall structure, and a reliable movement process.

[0014] In an optional manner, the cooling component includes a cooling sleeve, which is sleeved on the outer circumference of the valve stem to cool the flue gas at the valve port.

[0015] In this method, the cooling component is arranged at the valve port, and the cooling component is a shaft sleeve structure, which occupies a small space and is easy to install. It can cool the flue gas passing through the valve port, further reducing the possibility of the flue gas being ignited when passing through the valve port, and further ensuring safety.

[0016] In an optional manner, the cooling component includes a cooling sleeve, which is sleeved on the inner wall of the exhaust passage to cool the flue gas between the inlet and the valve port.

[0017] In this method, the cooling element is an annular structure, which is easy to process and only needs to be stuck on the inner wall of the exhaust passage, which is convenient for installation and removal. In addition, the cooling sleeve is arranged between the inlet and the valve port, which can cool the flue gas entering the exhaust passage, and the cooling is more sufficient and uniform, which can also further ensure safety.

[0018] In an optional manner, the pressure relief valve further comprises a plurality of filter screens, on which a plurality of filter holes are arranged, and the plurality of filter screens and the plurality of cooling elements are alternately arranged at the inlet in a direction from the inlet to the valve port.

[0019] In this method, multiple filters and multiple cooling components are alternately arranged at the entrance, which can filter and cool the smoke at the same time when the smoke enters the exhaust duct, so that the temperature and smoke particle concentration of the smoke entering the exhaust duct are relatively low, which reduces the possibility of ignition when the smoke is discharged from the valve port from two aspects, and further ensures safety.

[0020] In an optional manner, the size of the filter holes on each filter screen gradually decreases in the direction from the inlet to the valve port.

[0021] This method can make the smoke be screened in multiple layers, the smoke can be screened more fully, and each filter can play a screening role to avoid smoke particles being blocked on a certain filter, thereby achieving effective filtration of smoke particles and ensuring smooth smoke discharge.

[0022] In an optional manner, the filter holes on each filter screen are circular holes, the diameter of the circular holes is greater than or equal to 1 mm, and the diameter of the circular holes is less than or equal to 7 mm.

[0023] In this way, the filter holes are easy to process and can ensure that the filter holes can fully filter the smoke particles in the smoke.

[0024] In another aspect of the embodiment of the present application, a battery is provided, the battery comprising a frame, a plurality of battery cells, and any one of the above-mentioned pressure relief valves. The frame has a sealed internal space, and each battery cell is placed in the internal space. The pressure relief valve is installed on the frame so that the smoke in the internal space can be discharged from the internal space through the exhaust channel of the pressure relief valve.

[0025] When the battery pack is depressurized, the smoke will be discharged through the pressure relief valve. The cooling component using phase change material will cool the smoke so that the temperature of the smoke flowing through the pressure relief valve is always lower than the ignition point, avoiding the smoke from being ignited and causing a fire when discharged at high speed, and the battery pack is safer.

[0026] In the pressure relief valve and battery pack provided in the embodiment of the present application, the inlet of the exhaust channel is connected to the chamber to be relieved, so that the exhaust channel and the chamber to be relieved are connected, and the air pressure in the exhaust channel is consistent with the air pressure in the chamber to be relieved. When the air pressure in the chamber to be relieved and the exhaust channel is less than the exhaust threshold, the chamber to be relieved does not need to be relieved, and the movable component closes the valve port. When the air pressure in the chamber to be relieved and the exhaust channel rises to the exhaust threshold, the chamber to be relieved needs to be relieved, and the movable component moves under the action of the air pressure to expose the valve port, so that the smoke in the chamber to be relieved can be discharged through the exhaust channel to achieve the purpose of pressure relief. In addition, a cooling component made of phase change material is provided on the flow path of the smoke, which can cool the smoke in the pressure relief valve, so that the temperature of the smoke flowing through the pressure relief valve is always lower than the ignition point, thereby avoiding the smoke catching fire when discharged at high speed, and it is safer, simple in structure, and easy to assemble.

[0027] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the embodiment of the present application, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 An explosion schematic diagram of the pressure relief valve provided in an embodiment of the present application from a first perspective.

[0030] Figure 2 An explosion schematic diagram of the pressure relief valve provided in an embodiment of the present application at a second viewing angle.

[0031] Figure 3 An explosion schematic diagram of the pressure relief valve provided in an embodiment of the present application from a third perspective.

[0032] Figure 4 It is a front view of the valve port of the exhaust channel involved in the embodiment of the present application.

[0033] Figure 5 It is a cross-sectional view of the second valve body involved in the embodiment of the present application.

[0034] Figure 6 A comparative schematic diagram of the first filter, the second filter and the third filter involved in the embodiment of the present application.

[0035] Reference numerals:

[0036] 10. Valve body; 11. Exhaust channel; 12. Inlet; 13. Valve port; 14. First valve body; 15. Second valve body; 16. Slot; 17. Sealing ring;

[0037] 20. movable component; 21. elastic member; 22. movable member; 221. valve cover; 222. valve stem; 223. stopper;

[0038] 30. cooling member; 31. cooling sleeve; 32. cooling sleeve; 33. first cooling ring; 34. second cooling ring;

[0039] 40. filter; 41. first filter; 42. second filter; 43. third filter. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0042] The terms "comprising" and "having" and any variations thereof in the specification, claims and drawings of this application are intended to cover but not exclude other contents. The word "a" or "an" does not exclude the presence of a plurality.

[0043] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase "embodiments" in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0044] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0045] The directional words appearing in the following description are all directions shown in the drawings, and do not limit the specific structure of the pressure relief valve and battery pack of the present application. For example, in the description of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present application.

[0046] In addition, the expressions of the indicated directions, such as the X direction, the Y direction, and the Z direction, used to illustrate the operation and construction of the components of the pressure relief valve and the battery pack of this embodiment are not absolute but relative, and although these indications are appropriate when the components of the pressure relief valve and the battery pack are in the positions shown in the figures, when these positions change, these directions should be interpreted differently to correspond to the changes.

[0047] In addition, the terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects rather than to describe a specific order, and may explicitly or implicitly include one or more of the features.

[0048] In the description of the present application, unless otherwise specified, "plurality" means more than two (including two), and similarly, "multiple groups" means more than two groups (including two).

[0049] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, the "connection" or "connection" of a mechanical structure can refer to a physical connection. For example, the physical connection can be a fixed connection, such as a fixed connection through a fixing member, such as a fixed connection through a screw, bolt or other fixing member; the physical connection can also be a detachable connection, such as a mutual snap connection or snap connection; the physical connection can also be an integral connection, such as welding, bonding or integral molding to form a connection for connection. The "connection" or "connection" of a circuit structure can refer to not only a physical connection, but also an electrical connection or a signal connection. For example, it can be a direct connection, that is, a physical connection, or it can be indirectly connected through at least one intermediate element, as long as the circuit is connected, and it can also be the internal connection of two elements; in addition to signal connection through a circuit, a signal connection can also refer to signal connection through a media medium, such as a radio wave. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0050] The pressure relief valve provided in the embodiment of the present application is specifically as follows Figure 1 , Figure 2 and Figure 3 As shown, Figure 1 An exploded schematic diagram of a pressure relief valve provided in an embodiment of the present application at a first viewing angle, Figure 2 An exploded schematic diagram of the pressure relief valve provided in an embodiment of the present application at a second viewing angle, Figure 3 An exploded schematic diagram of a pressure relief valve provided in an embodiment of the present application at a third viewing angle. The pressure relief valve includes a valve body 10, a movable component 20 and at least one cooling element 30.

[0051] The valve body 10 is the outer shell of the pressure relief valve, and is used to provide a mounting position and support for components such as the movable assembly 20 and the cooling member 30. The valve body 10 is made of high-strength, high-temperature resistant materials to ensure stability and durability under high-pressure and high-temperature environments.

[0052] The valve body 10 may be formed by a single integrally formed part, or may be formed by assembling a plurality of parts. Figure 1 , Figure 2 and Figure 3 As shown, the valve body 10 can be assembled by butting a first valve body 14 and a second valve body 15 together by means of threaded connection or the like.

[0053] An exhaust passage 11 is provided in the valve body 10. The exhaust passage 11 can be a straight passage or a curved passage, as long as it can allow the smoke to pass smoothly. The exhaust passage 11 can be a separately formed passage or can be assembled from passages of multiple parts.

[0054] For example, when the valve body 10 is assembled from the first valve body 14 and the second valve body 15, the exhaust passage 11 is as follows. Figure 2 and Figure 3 As shown, it is formed by splicing the channels of the first valve body 14 and the second valve body 15. Figure 1 , Figure 2 and Figure 3 As shown, in order to ensure the air tightness of the assembled exhaust passage 11 , a sealing ring 17 and other structures may be provided to ensure the air tightness of the exhaust passage 11 .

[0055] The two ends of the exhaust channel 11 are an inlet 12 and a valve port 13, respectively. The inlet 12 is used to connect with the chamber to be depressurized. The chamber to be depressurized refers to the cavity space that needs to be depressurized by the pressure relief valve, which can specifically be the internal space of the battery pack. The inlet 12 of the exhaust channel 11 connects with the chamber to be depressurized, so that the exhaust channel 11 and the chamber to be depressurized are connected, and the gas in the chamber to be depressurized will be filled in the exhaust channel 11, so that the air pressure in the exhaust channel 11 is equal to the air pressure in the chamber to be depressurized.

[0056] There are many ways to connect the inlet 12 and the chamber to be depressurized. For example, the inlet 12 and the chamber to be depressurized can be connected by threaded connection, welding, bonding or clamping. In addition, the inlet 12 and the chamber to be depressurized should be sealed when connected. This can be achieved by providing sealing parts such as sealing rings, applying sealant, etc.

[0057] The valve port 13 is a channel port for directly discharging gas to the outside. The structure of the valve port 13 corresponds to the structure of the movable component 20, and the movable component 20 is movably arranged at the valve port 13, so that the movable component 20 can reliably close the valve port 13 when pressure relief is not required. When pressure relief is required, the movable component 20 can move under the action of air pressure to expose the valve port 13 to facilitate smoke discharge.

[0058] In a specific embodiment, the movable component 20 closes the valve port 13 when the air pressure in the exhaust channel 11 is less than the exhaust threshold, and is pushed open by the smoke in the exhaust channel 11 to expose the valve port 13 when the air pressure in the exhaust channel 11 reaches the exhaust threshold.

[0059] That is to say, when the air pressure in the chamber to be depressurized is small and no depressurization is required, the air pressure in the chamber to be depressurized and the exhaust channel 11 is less than the exhaust threshold, the valve port 13 is always closed by the movable component 20, and the chamber to be depressurized and the exhaust channel 11 are always a closed space. When the air pressure in the chamber to be depressurized rises to the point where depressurization is required, the air pressure in the chamber to be depressurized and the exhaust channel 11 reaches the exhaust threshold, at which time the movable component 20 can be pushed by the air pressure of the flue gas, thereby moving away from the position where the valve port 13 is closed, exposing the valve port 13, so that the flue gas in the chamber to be depressurized can be discharged from the valve port 13 through the exhaust channel 11 to the outside, thereby achieving the purpose of depressurization. Among them, the exhaust threshold is a preset air pressure value. When the air pressure in the chamber to be depressurized and the exhaust channel 11 reaches the exhaust threshold, the gas pressure on the movable component 20 can cause the movable component 20 to move to expose the valve port 13.

[0060] There are many specific implementations of the movable component 20. The movable component 20 can be set as a piston-type structure or a flip-type structure, as long as it can reliably close the valve port 13 and can promptly respond to the pressure change of the chamber to be depressurized to move, so as to timely and reliably expose the valve port 13 for depressurization.

[0061] For example, an optional method is as follows Figure 1 , Figure 2 and Figure 3 As shown, the movable assembly 20 includes an elastic member 21 and a movable member 22, and the movable member 22 is movably arranged at the valve port 13. When the air pressure in the exhaust channel 11 is less than the exhaust threshold, the movable member 22 closes the valve port 13 under the elastic force of the elastic member 21. When the air pressure in the exhaust channel 11 reaches the exhaust threshold, the movable member 22 is pushed open by the smoke in the exhaust channel 11 to expose the valve port 13.

[0062] The movable member 22 and the elastic member 21 are connected, so that the elastic member 21 acts on the movable member 22 and provides elastic force for the movable member 22. When the air pressure in the exhaust channel 11 is less than the exhaust threshold, the pressure applied by the smoke in the exhaust channel 11 to the movable member 22 is less than the elastic force applied by the spring to the movable member 22, and the movable member 22 always closes the valve port 13. When the air pressure in the exhaust channel 11 reaches the exhaust threshold, the pressure applied by the smoke in the exhaust channel 11 to the movable member 22 is greater than the elastic force applied by the spring to the movable member 22, and the movable member 22 is pushed open by the smoke in the exhaust channel 11, thereby exposing the valve port 13, so that the smoke in the chamber to be depressurized flows through the exhaust channel 11 and is discharged to the outside, and the air pressure in the chamber to be depressurized can be reduced.

[0063] In this manner, the elastic member 21 and the movable member 22 cooperate with each other to realize the closing and opening of the valve port 13 , which has a simple structure, reliable operation, and is easy to assemble and debug.

[0064] There are many specific forms of the elastic member 21 and the movable member 22. One optional method is as follows: Figure 1 and Figure 4 As shown, Figure 4 It is a front view of the valve port of the exhaust passage involved in the embodiment of the present application. Among them, the elastic member 21 is a spring. The movable member 22 includes a valve cover 221, a valve stem 222 and a resisting portion 223. The valve cover 221 and the resisting portion 223 are located at opposite ends of the valve stem 222, and the valve stem 222 passes through the valve port 13, so that the resisting portion 223 is located in the exhaust passage 11. The spring is arranged between the resisting portion 223 and the valve body 10, so that the valve cover 221 can close the valve port 13 under the elastic force of the spring.

[0065] The spring is arranged between the valve body 10 and the resisting portion 223 to provide elastic force for the movable member 22. The spring can be a compression spring, a tension spring or other structural forms, and it is only necessary to ensure that the valve cover 221 of the movable member 22 can reliably close the valve port 13 when the air pressure in the chamber to be depressurized and the exhaust channel 11 is less than the exhaust threshold, and the movable member 22 can be pushed open by the gas when the air pressure in the chamber to be depressurized and the exhaust channel 11 reaches the exhaust threshold.

[0066] For example, when the spring is a compression spring, the two ends of the compression spring can be respectively pressed against the valve port 13 and the stopper 223. When the air pressure in the chamber to be depressurized and the exhaust channel 11 is less than the exhaust threshold, the compression spring is in a compressed state. The elastic force of the elastic member 21 acts on the movable member 22, so that the force direction of the movable member 22 is from the valve port 13 to the inlet 12, so that the valve cover 221 of the movable member 22 can reliably close the valve port 13. When the air pressure in the chamber to be depressurized and the exhaust channel 11 reaches the exhaust threshold, the valve cover 221 is pushed outward by the air pressure force, and the air pressure force will overcome the elastic force of the compression spring, pushing the valve cover 221 outward, thereby exposing the valve port 13 for pressure relief.

[0067] In this mode, the elastic member 21 is configured as a spring, and the movable member 22 and the valve port 13 form a piston structure. The movable member 22 moves in a simple linear motion, requires a small space for movement, has a compact overall structure, and is reliable in the movement process.

[0068] The cooling element 30 is a structure for cooling the flue gas to prevent the flue gas from being ignited. The cooling element 30 uses a phase change material (PCM) and is installed in the exhaust passage 11 and located on the flow path of the flue gas to cool the flue gas flowing through the exhaust passage 11.

[0069] The cooling component 30 uses phase change material, which allows the cooling component 30 to change the material state in a high temperature environment, such as from solid to liquid, or from liquid to gas, etc., thereby absorbing the heat of the flue gas near the cooling component 30 and controlling the temperature of the flue gas below the ignition point, making it difficult for the flue gas to ignite when discharged at a high speed.

[0070] The cooling element 30 can be arranged in the exhaust passage 11 by means of a clamping connection. A feasible method is as follows: Figure 5 As shown, Figure 5 2 is a cross-sectional view of the second valve body involved in the embodiment of the present application, wherein a slot 16 is provided on the inner wall of the exhaust passage 11 to clamp the cooling element 30 in the slot 16. Alternatively, the cooling element 30 may also be provided in the exhaust passage 11 by bonding or the like, which is not limited here.

[0071] There are many specific implementations when the cooling element 30 uses a phase change material. The cooling element 30 can use a suitable phase change material according to the required phase change material type. For example, the cooling element 30 can use an inorganic phase change material, an inorganic phase change material, or a composite phase change material. The cooling element 30 can also use a suitable phase change material according to the material state of the phase change material. For example, the cooling element 30 can use a phase change material that is solid at room temperature, and the cooling element 30 can also use a composite phase change material that is in a gel state at room temperature.

[0072] Furthermore, in order to prevent material loss when the phase change material changes its physical form, a packaging film that wraps the cooling element 30 may be provided on the cooling element 30 , or a structure that collects the cooling element 30 may be provided at the installation position of the cooling element 30 .

[0073] In this embodiment, the cooling element 30 can be configured in various shapes such as annular, sleeve, block, etc., which are not limited here. In addition, the cooling element 30 can be one or more, and the cooling element 30 can be set at different positions of the exhaust passage 11 to achieve different cooling effects.

[0074] In an optional manner, the cooling element 30 may be disposed at the inlet 12 . A specific implementation may be that a plurality of cooling elements 30 are arranged at the inlet 12 along a direction from the inlet 12 to the valve port 13 to cool the flue gas at the inlet 12 .

[0075] The specific implementation method can be as follows Figure 1 , Figure 2 and Figure 3 As shown, the cooling element 30 includes a first cooling ring 33 and a second cooling ring 34, which are arranged at the position where the inlet 12 is located, and the first cooling ring 33 and the second cooling ring 34 can be installed through a plurality of slots 16 set at the position where the inlet 12 is located, thereby cooling the flue gas at the inlet 12.

[0076] In this method, a plurality of cooling components 30 are provided at the entrance 12 of the exhaust passage 11, which can cool the smoke in the pressure relief chamber when the smoke enters the exhaust passage 11. The cooling effect is better and it can ensure that the smoke entering the exhaust passage 11 is low-temperature smoke, so that the smoke is not easy to catch fire when discharged at a high speed.

[0077] In another optional manner, the cooling element 30 may be disposed at the valve port 13. A specific implementation may be as follows: Figure 1 As shown, the cooling member 30 includes a cooling sleeve 31 , which is sleeved on the outer periphery of the valve stem 222 to cool the flue gas at the valve port 13 .

[0078] In this method, the cooling element 30 is arranged at the valve port 13, and the cooling element 30 is a shaft sleeve structure, which occupies a small space and is easy to install. It can cool the flue gas passing through the valve port 13, further reducing the possibility of the flue gas being ignited when passing through the valve port 13, and further ensuring safety.

[0079] In another optional manner, the cooling element 30 may be disposed in the exhaust passage 11 between the inlet 12 and the valve port 13, so as to cool the flue gas in the exhaust passage 11. Figure 1 , Figure 2 and Figure 3 As shown, the cooling element 30 includes a cooling sleeve 32. The cooling sleeve 32 is sleeved on the inner wall of the exhaust passage 11 to cool the flue gas between the inlet 12 and the valve port 13.

[0080] In this method, the cooling member 30 is an annular structure, which is easy to process and only needs to be stuck on the inner wall of the exhaust passage 11, which is convenient for installation and removal. In addition, the cooling sleeve 32 is arranged between the inlet 12 and the valve port 13, which can cool the flue gas entering the exhaust passage 11, and the cooling is more sufficient and uniform, and safety can be further ensured.

[0081] In addition, when there are multiple cooling components 30, the cooling components 30 can be respectively set at the inlet 12, the valve port 13, and multiple positions of the exhaust passage 11 between the inlet 12 and the valve port 13, so that the flue gas can be cooled more fully to further ensure the safety of the pressure relief valve.

[0082] In this embodiment, in addition to providing a cooling component 30 in the pressure relief valve, a filter 40 may be provided at the inlet 12 to filter smoke particles in the flue gas, so as to reduce the concentration of smoke particles in the flue gas passing through the exhaust passage 11, thereby reducing the possibility of ignition of smoke particles and further improving the safety of the pressure relief valve.

[0083] The filter 40 serves as a structure for filtering smoke particles, and it can be set as a rigid structure. For example, the filter 40 can be made of stainless steel, and the parameters of the filter 40 made of this material can be restricted, such as making the tensile tension of the filter 40 greater than or equal to 450 Newtons, the yield tension greater than or equal to 250 Newtons, and the elongation greater than or equal to 20%.

[0084] In this embodiment, the filter screen 40 can be provided as a single one or as a plurality of ones. The shape of the filter screen 40 can be provided as a circle, a square, an ellipse, etc. When a plurality of filter screens 40 are provided, the material, size, filter hole size, and shape of each filter screen 40 can be the same or different.

[0085] In this embodiment, the filter 40 can be arranged in conjunction with the cooling element 30, so as to filter smoke particles in the smoke and cool the smoke, thereby further ensuring safety. In an optional manner, the pressure relief valve further includes a plurality of filter screens 40, and the filter screens 40 are provided with a plurality of filter holes. The plurality of filter screens 40 and the plurality of cooling elements 30 are alternately arranged at the inlet 12 along the direction from the inlet 12 to the valve port 13.

[0086] The specific implementation method can be as follows Figure 1 , Figure 2 and Figure 3 As shown, the first cooling ring 33 and the second cooling ring 34 are provided at the inlet 12, and the first filter screen 41, the second filter screen 42 and the third filter screen 43 are also provided. In the direction from the inlet 12 to the valve port 13, the first filter screen 41, the first cooling ring 33, the second filter screen 42, the second cooling ring 34 and the third filter screen 43 are arranged in sequence, so as to filter and cool the discharged flue gas at the same time.

[0087] Each filter screen 40 and each cooling element 30 can be arranged at intervals, that is, there is an interval between each component. For example, the interval between each two adjacent filter screens 40 can be between 9 mm and 12 mm.

[0088] There are many ways to alternately arrange the filter screens 40 and the cooling elements 30. For example, one or more cooling elements 30 may be arranged between two adjacent filter screens 40, or one or more filter screens 40 may be arranged between two adjacent cooling elements 30.

[0089] When the filter screen 40 and the cooling element 30 are arranged alternately along the direction from the inlet 12 to the valve port 13, the filter screen 40 can be arranged at the front end, that is, in the direction from the inlet 12 to the valve port 13, a filter screen 40 is arranged first, and then the cooling element 30 and other filter screens 40 are arranged, so that when the smoke enters the exhaust, it is first filtered by the first filter screen 40, and then cooled and filtered by the cooling element 30 and other filter screens 40. Of course, it is also possible to first arrange a cooling element 30 in the direction from the inlet 12 to the valve port 13, and then arrange the filter screen 40 and other cooling elements 30, which is not limited here.

[0090] In this manner, a plurality of filters 40 and a plurality of cooling elements 30 are alternately arranged at the inlet 12, which can filter and cool the smoke at the same time when the smoke enters the exhaust duct 11, so that the temperature and smoke particle concentration of the smoke entering the exhaust duct 11 are relatively low, thereby reducing the possibility of ignition when the smoke is discharged from the valve port 13 from two aspects, thereby further ensuring safety.

[0091] The filter holes of the filter screen 40 can be set to be circular or polygonal. When multiple filter screens 40 are provided, the filter hole shapes of each filter screen 40 can be the same or different, and the filter hole sizes of each filter screen 40 can also be different. Exemplarily, in an optional manner, in the direction from the inlet 12 to the valve port 13, the size of the filter holes on each filter screen 40 gradually decreases, that is, in the direction from the inlet 12 to the valve port 13, the filter holes of the filter screen 40 located in the front are larger than the filter holes of the filter screen 40 located in the rear.

[0092] For example, a specific implementation can be as follows Figure 1 and Figure 6 As shown, Figure 6 A comparative schematic diagram of the first filter, the second filter and the third filter involved in the embodiment of the present application is shown in FIG. Among them, the filter hole size of the first filter 41 is the largest, the filter hole size of the second filter 42 is the second largest, and the filter hole size of the third filter 43 is the smallest, so as to facilitate multi-layer screening of smoke particles in the smoke.

[0093] This method can make the smoke be screened in multiple layers, the smoke can be screened more fully, and each filter 40 can play a screening role to avoid smoke particles being blocked on a certain filter, thereby achieving effective filtering of smoke particles and ensuring smooth smoke discharge.

[0094] And, if Figure 1 and Figure 6 As shown, when the inlet 12 is a funnel shape with a gradually decreasing diameter, the overall outline size of the filter 40 can be gradually reduced in the direction from the inlet 12 to the valve port 13, such as reducing the sizes of the first filter 41, the second filter 42 and the third filter 43 in turn, thereby ensuring the filtering effect while making the size of the filter 40 adapt to the shape of the inlet 12 of the exhaust channel 11.

[0095] In addition, the filter holes of each filter screen 40 can be staggered, that is, the filter holes of each filter screen 40 are not aligned, so as to further ensure the screening effect.

[0096] In this embodiment, the size of each filter hole and the size of the filter holes on each filter screen 40 can be freely set according to demand. When the pressure relief valve is used on the battery pack, the size of the filter screen 40 and the filter hole can be set smaller. Exemplarily, in an optional manner, each filter screen 40 can be circular, and the diameter of each filter screen 40 can be greater than or equal to 30 mm, and the diameter of each filter screen 40 can be less than or equal to 60 mm. And the filter holes on each filter screen 40 can be circular holes, the diameter of the circular holes is greater than or equal to 1 mm, and the diameter of the circular holes is less than or equal to 7 mm, so that the filter holes are easy to process, and at the same time, it can be ensured that the filter holes can fully filter the smoke particles in the smoke.

[0097] The first embodiment above introduces a pressure relief valve in detail. The second embodiment below introduces a battery pack including the pressure relief valve of the first embodiment, and the details are as follows.

[0098] The battery pack includes a frame, a plurality of battery cells, and the pressure relief valve of the first embodiment. The frame has a sealed internal space, and each battery cell is placed in the internal space. The pressure relief valve is installed on the frame so that the smoke in the internal space can be discharged from the internal space through the exhaust channel of the pressure relief valve.

[0099] In this type of battery pack, the frame forms the supporting structure of the battery pack shell. The internal space in the frame is equivalent to the pressure relief chamber, and the inlet of the exhaust channel on the valve body of the pressure relief valve is sealed and connected to the inner wall space of the frame, so that the exhaust channel and the internal space of the battery pack are connected.

[0100] There may be one or more pressure relief valves on this type of battery pack. The specific structure of the pressure relief valve corresponds to the pressure relief valve in the aforementioned embodiment. The specific structural setting of the pressure relief valve refers to the introduction of the pressure relief valve in any embodiment related to the pressure relief valve. The similarities will not be described in detail in this embodiment.

[0101] The battery cells in the battery pack generate smoke during the charging and discharging process, and the air pressure in the internal space of the battery pack continues to increase. When the air pressure reaches the exhaust threshold, the gas will push the active component of the pressure relief valve, causing the active component to move and expose the valve port, and the smoke will be discharged from the exhaust channel of the pressure relief valve. When the smoke is discharged through the pressure relief valve, the cooling element using phase change material will cool the smoke, so that the temperature of the smoke flowing through the pressure relief valve is always lower than the ignition point, avoiding the smoke from being ignited during high-speed discharge and causing a fire, and the battery pack is safer.

[0102] In summary, in the pressure relief valve and battery pack described above, the inlet of the exhaust channel is connected to the chamber to be relieved, so that the exhaust channel and the chamber to be relieved are connected, and the air pressure in the exhaust channel is consistent with the air pressure in the chamber to be relieved. When the air pressure in the chamber to be relieved and the exhaust channel is less than the exhaust threshold, the chamber to be relieved does not need to be relieved, and the movable component closes the valve port. When the air pressure in the chamber to be relieved and the exhaust channel rises to the exhaust threshold, the chamber to be relieved needs to be relieved, and the movable component moves under the action of the air pressure to expose the valve port, so that the smoke in the chamber to be relieved can be discharged through the exhaust channel to achieve the purpose of pressure relief. In addition, a cooling component made of phase change material is provided on the flow path of the smoke, which can cool the smoke in the pressure relief valve, so that the temperature of the smoke flowing through the pressure relief valve is always lower than the ignition point, thereby avoiding the smoke catching fire when discharged at high speed. It is safer, has a simple structure, and is easy to assemble.

[0103] Those skilled in the art will appreciate that, although some embodiments herein do not include certain features included in other embodiments, the combination of features of different embodiments is still within the scope of the present application and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0104] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A pressure relief valve, characterized in that: The pressure relief valve comprises: a valve body, a movable component and at least one temperature reducing component; The valve body is provided with an exhaust channel, and the two ends of the exhaust channel are respectively an inlet and a valve port; The inlet is used to dock with the chamber to be depressurized, and the movable component is movably arranged at the valve port; the movable component closes the valve port when the air pressure in the exhaust channel is less than the exhaust threshold, and the movable component is pushed open by the smoke in the exhaust channel to expose the valve port when the air pressure in the exhaust channel reaches the exhaust threshold; The temperature-reducing component is made of phase-change material and is installed in the exhaust passage and located on the flow path of the smoke to reduce the temperature of the smoke flowing through the exhaust passage.

2. The pressure relief valve according to claim 1, characterized in that: A plurality of cooling elements are arranged at the inlet along a direction from the inlet to the valve port to cool the flue gas at the inlet.

3. The pressure relief valve according to claim 1, characterized in that: The movable component comprises an elastic member and a movable member; The movable part is movably arranged at the valve port; when the air pressure in the exhaust channel is lower than the exhaust threshold, the movable part closes the valve port under the elastic force of the elastic part; when the air pressure in the exhaust channel reaches the exhaust threshold, the movable part is pushed open by the smoke in the exhaust channel to expose the valve port.

4. The pressure relief valve according to claim 3, characterized in that: The elastic member is a spring; the movable member includes a valve cover, a valve stem and a resisting portion; The valve cover and the resisting portion are located at opposite ends of the valve stem, and the valve stem passes through the valve port so that the resisting portion is located in the exhaust passage; the spring is arranged between the resisting portion and the valve body so that the valve cover can close the valve port under the elastic force of the spring.

5. The pressure relief valve according to claim 4, characterized in that: The cooling component comprises a cooling sleeve, which is sleeved on the outer periphery of the valve stem to cool the flue gas at the valve port.

6. The pressure relief valve according to claim 1 or 2, characterized in that: The cooling element comprises a cooling sleeve; the cooling sleeve is sleeved on the inner wall of the exhaust passage to cool the flue gas between the inlet and the valve port.

7. The pressure relief valve according to claim 1 or 2, characterized in that: The pressure relief valve further comprises a plurality of filter screens, wherein the filter screens are provided with a plurality of filter holes; The plurality of filter screens and the plurality of cooling elements are alternately arranged at the inlet along a direction from the inlet to the valve port.

8. The pressure relief valve according to claim 7, characterized in that: In the direction from the inlet to the valve port, the size of the filter holes on each filter screen gradually decreases.

9. The pressure relief valve according to claim 7, characterized in that: The filter holes on each filter screen are circular holes, the diameter of the circular holes is greater than or equal to 1 mm, and the diameter of the circular holes is less than or equal to 7 mm.

10. A battery pack, characterized in that: The battery pack comprises a frame, a plurality of battery cells, and a pressure relief valve according to any one of claims 1 to 9; The frame has a sealed internal space, and each of the battery cells is placed in the internal space; The pressure relief valve is mounted on the frame so that smoke in the internal space can be discharged from the internal space through the exhaust passage of the pressure relief valve.

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