Explosion-proof valve, battery pack and electric device

Abstract

The utility model discloses an explosion-proof valve, a battery pack and an electric device, the explosion-proof valve comprises a valve body (5), an exhaust hole channel (51) is arranged on the valve body (5), and an exhaust outlet of the exhaust hole channel (51) is arranged on the outer end face of the valve body (5); the piston (7) is movably arranged on the outer end face of the exhaust hole channel (51) in a covering mode so as to be switched between a first position where the exhaust hole channel (51) is closed and a second position where the exhaust hole channel (51) is opened, and the piston (7) is configured to be switched to the second position under the action of exhaust pressure of the exhaust hole channel (51); the labyrinth type sealing structure comprises a first annular groove (53) arranged outside an exhaust outlet of the exhaust hole channel (51) in a sleeving mode and an annular protrusion (72) embedded in the first annular groove (53), one of the first annular groove (53) and the annular protrusion (72) is arranged on the outer end face of the valve body (5), and the other one of the first annular groove (53) and the annular protrusion (72) is arranged on the piston (7).

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to an explosion-proof valve, a battery pack and an electrical device. Background Art

[0002] New energy batteries are increasingly used in life and industry. For example, new energy vehicles equipped with batteries have been widely used. In addition, batteries are increasingly used in the field of energy storage. In new energy vehicles equipped with batteries, batteries can be used to provide power in whole or in part. In the field of energy storage, batteries can be installed in energy storage boxes or directly on the user side.

[0003] An explosion-proof valve is installed on the battery case to prevent the risk of explosion caused by abnormal conditions such as overheating and overcharging, and to ensure the safe operation of the battery. When the battery is working normally, the explosion-proof valve seals the case to ensure the normal operation of the battery; when the battery has thermal runaway, the explosion-proof valve needs to open the explosion-proof function in time to discharge the internal gas and heat in time to reduce the risk of explosion. The piston of the explosion-proof valve has the problem of being stuck by foreign objects, resulting in poor sealing performance. Utility Model Content

[0004] The utility model aims to provide an explosion-proof valve, a battery pack and an electric device, so as to improve the problem in the prior art that the piston of the explosion-proof valve is stuck by foreign matter, resulting in poor sealing performance.

[0005] According to one aspect of an embodiment of the utility model, the utility model provides an explosion-proof valve, which includes: a valve body, which is provided with an exhaust channel, and the exhaust outlet of the exhaust channel is arranged on the outer end surface of the valve body; a piston, which is movably covered on the outer end surface of the exhaust channel to switch between a first position closing the exhaust channel and a second position opening the exhaust channel, and the piston is configured to switch to the second position under the action of the exhaust pressure of the exhaust channel; a labyrinth sealing structure, including a first annular groove sleeved outside the exhaust outlet of the exhaust channel and an annular protrusion embedded in the first annular groove, one of the first annular groove and the annular protrusion is arranged on the outer end surface of the valve body, and the other is arranged on the piston.

[0006] In some embodiments, the piston includes a plate-like component that is covered on the outer end surface of the valve body and closes the exhaust outlet of the exhaust channel, an annular protrusion is arranged on a side of the plate-like component facing the valve body, and a first annular groove is arranged on the outer end surface of the valve body.

[0007] In some embodiments, a groove matched with the piston is provided on the outer end surface of the valve body, the piston is embedded in the groove, and the first annular groove is provided at the bottom of the groove.

[0008] In some embodiments, a surface of the piston facing away from the bottom of the groove is flush with an outer end surface of the valve body.

[0009] In some embodiments, the explosion-proof valve further comprises a sealing cover which is covered on the outer end surface of the valve body, the sealing cover is located on a side of the piston away from the valve body, and the sealing cover at least covers the groove.

[0010] In some embodiments, the sealing cover is connected to the piston.

[0011] In some embodiments, the sealing cover and the piston are bonded together; or, the sealing cover and the piston are connected together by a rubber layer covering the outside of both.

[0012] In some embodiments, the explosion-proof valve further includes a first sealing ring which is sleeved outside the exhaust outlet of the exhaust channel and cooperates with the piston to seal the exhaust outlet.

[0013] In some embodiments, the first sealing ring is disposed within the labyrinth sealing structure.

[0014] In some embodiments, the explosion-proof valve further includes: an elastic pushing mechanism configured to push the piston toward the first position; and a protective sleeve mounted on the elastic pushing mechanism and located at the upstream end of the valve body along the exhaust direction of the exhaust channel.

[0015] In some embodiments, a mounting hole is provided on the valve body, and the elastic pushing mechanism includes: a guide rod, which is slidably provided in the mounting hole, and one end of the guide rod is connected to the piston so as to move with the piston relative to the valve body; an elastic component, which is configured to elastically push the guide rod and enable the guide rod to drive the piston to move toward the first position.

[0016] In some embodiments, a protrusion is provided on the guide rod, the protrusion is located on a side of the valve body away from the piston, and the elastic component is sleeved on the guide rod and located between the protrusion and the valve body.

[0017] In some embodiments, the explosion-proof valve further comprises a driving component for driving the piston toward the second position.

[0018] In some embodiments, the driving component includes a magnetic attraction component.

[0019] According to another aspect of the present invention, a battery pack is provided, which includes the above-mentioned explosion-proof valve.

[0020] According to another aspect of the present invention, an electric device is also provided. In some embodiments, the electric device includes the above-mentioned battery pack.

[0021] By applying the technical solution of the utility model, the labyrinth sealing structure is sleeved outside the exhaust outlet of the exhaust duct, which is beneficial to prevent external mud and sand and other debris from invading the sealing interface formed by the piston and the valve body around the exhaust outlet, and is beneficial to prevent the above-mentioned sealing interface from failing, thereby improving the problem that the above-mentioned mud and sand and other debris affect the sealing performance of the explosion-proof valve.

[0022] Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 A schematic structural diagram of an electric device disclosed in some embodiments of the utility model is shown.

[0025] Figure 2 A schematic diagram of the exploded structure of a battery pack disclosed in some embodiments of the utility model is shown.

[0026] Figure 3 A schematic structural diagram of a battery cell disclosed in some embodiments of the utility model is shown.

[0027] Figure 4 A schematic structural diagram of a battery pack disclosed in some embodiments of the utility model is shown.

[0028] Figure 5 A three-dimensional structural schematic diagram of an explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0029] Figure 6 A schematic diagram of the main structure of an explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0030] Figure 7 A schematic diagram of the top view of an explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0031] Figure 8 A schematic cross-sectional structure diagram of an explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0032] Fig. 9 Shows Figure 8 A partial enlarged view of .

[0033] Fig.10 A schematic cross-sectional structure diagram of an open explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0034] Fig.11A schematic cross-sectional structure diagram of an open explosion-proof valve disclosed in some embodiments of the utility model is shown.

[0035] In the figure: 1000, vehicle; 100, battery pack; 110, box; 111, first part; 112, second part; 120, battery cell; 121, end cover; 121a, electrode terminal; 122, shell; 123, battery cell assembly; 123a, pole ear; 200, controller; 300, motor; 10, explosion-proof valve; 1, sealing cover; 2, guide rod; 21, protrusion; 3, elastic component; 4, second sealing ring; 5, valve body; 51, exhaust duct; 52, connecting part; 53, first annular groove; 54, groove; 6, driving component; 7, piston; 71, plate-like component; 72, annular protrusion; 8, protective cover; 9, first sealing ring. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0037] In the description of the present utility model, it should be noted that, unless otherwise specified, "multiple" means more than two; the terms "upper", "lower", "left", "right", "inside", "outside", etc., indicating the orientation or positional relationship, are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not strictly vertical, but is within the allowable error range. "Parallel" is not strictly parallel, but is within the allowable error range.

[0038] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of the utility model. In the description of the utility model, it should also be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to the specific circumstances.

[0039] Further, the "scope" disclosed in the utility model is limited in the form of a lower limit and an upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be inclusive or exclusive of end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60-120 and 80-110 is listed for a particular parameter, it is understood that the range of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the utility model, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0040] If not otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form a new technical solution.

[0041] Unless otherwise specified, all technical features and optional technical features of the utility model can be combined with each other to form a new technical solution.

[0042] If there is no special explanation, all steps of the utility model can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), which means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0043] If there is no special explanation, the "include" and "comprising" mentioned in the present invention may be open or closed. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0044] If not specifically stated, in the present invention, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0045] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0046] Figure 1 FIG. 1 shows a schematic diagram of a structure of an electric device using a battery as a power source; Figure 1 As shown, the power-consuming device of this embodiment includes a vehicle 1000, which may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. A battery pack 100 is disposed inside the vehicle 1000, and the battery pack 100 may be disposed at the bottom, head, or tail of the vehicle 1000. The battery pack 100 may be used to power the vehicle 1000, for example, the battery pack 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery pack 100 to power the motor 300, for example, for the starting, navigation, and working power requirements of the vehicle 1000 during driving.

[0047] In some embodiments of the present invention, the battery pack 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0048] Please refer to Figure 2 , Figure 2 An exploded view of a battery pack 100 provided for some embodiments of the utility model. The battery pack 100 includes a case 110 and a battery module disposed in the case 110, the battery module includes a plurality of battery cells 120, and the battery cells 120 are accommodated in the case 110. Among them, the case 110 is used to provide a storage space for the battery cells 120, and the case 110 can adopt a variety of structures. In some embodiments, the case 110 may include a first portion 111 and a second portion 112, the first portion 111 and the second portion 112 cover each other, and the first portion 111 and the second portion 112 jointly define a storage space for accommodating the battery cells 120. The second part 112 may be a hollow structure with one end open, and the first part 111 may be a plate-like structure, and the first part 111 covers the open side of the second part 112, so that the first part 111 and the second part 112 jointly define a storage space; the first part 111 and the second part 112 may also be hollow structures with one side open, and the open side of the first part 111 covers the open side of the second part 112. Of course, the box body 110 formed by the first part 111 and the second part 112 may be in various shapes, such as a cylinder, a cuboid, etc.

[0049] In the battery pack 100, there may be multiple battery cells 120, and the multiple battery cells 120 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 120 are both connected in series and in parallel. The multiple battery cells 120 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 120 is accommodated in the box 110; of course, the battery pack 100 may also be a battery module formed by connecting multiple battery cells 120 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 110. The battery pack 100 may also include other structures, for example, the battery pack 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 120.

[0050] Each battery cell 120 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 120 may be cylindrical, flat, rectangular, or in other shapes.

[0051] Please refer to Figure 3 , Figure 3The schematic diagram of the exploded structure of the battery cell 120 provided in some embodiments of the present invention. The battery cell 120 refers to the smallest unit constituting the battery pack 100. Figure 3 The battery cell 120 includes an end cover 121, a shell 122, a battery cell assembly 123 and other functional components.

[0052] The end cap 121 refers to a component that covers the opening of the shell 122 to isolate the internal environment of the battery cell 120 from the external environment. Without limitation, the shape of the end cap 121 can be adapted to the shape of the shell 122 to match the shell 122. Optionally, the end cap 121 can be made of a material with a certain hardness and strength, such as an aluminum alloy, so that the end cap 121 is not easily deformed when squeezed and collided, so that the battery cell 120 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 121a can be provided on the end cap 121. The electrode terminal 121a can be used to electrically connect to the battery cell assembly 123 for outputting or inputting electrical energy of the battery cell 120. In some embodiments, the end cap 121 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 120 reaches a threshold. The material of the end cap 121 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the utility model does not impose any special restrictions on this. In some embodiments, an insulating member can also be provided on the inner side of the end cap 121, and the insulating member can be used to isolate the electrical connection components in the housing 122 from the end cap 121 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc.

[0053] The shell 122 is a component used to cooperate with the end cap 121 to form the internal environment of the battery cell 120, wherein the formed internal environment can be used to accommodate the battery cell assembly 123, electrolyte and other components. The shell 122 and the end cap 121 can be independent components, and an opening can be set on the shell 122, and the internal environment of the battery cell 120 is formed by covering the opening with the end cap 121 at the opening. Without limitation, the end cap 121 and the shell 122 can also be integrated. Specifically, the end cap 121 and the shell 122 can form a common connection surface before other components are put into the shell, and when it is necessary to encapsulate the interior of the shell 122, the end cap 121 covers the shell 122. The shell 122 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 122 can be determined according to the specific shape and size of the battery cell assembly 123. The shell 122 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention does not impose any special limitation on this.

[0054] The cell assembly 123 is a component where electrochemical reactions occur in the battery cell 120. The housing 122 may contain one or more cell assemblies 123. The cell assembly 123 is mainly formed by winding or stacking pole sheets, wherein the pole sheets include a positive pole sheet and a negative pole sheet, and a separator is usually provided between the positive pole sheet and the negative pole sheet.

[0055] The electrode sheet mainly includes a thin sheet-shaped current collector and an active material coated on the current collector. The parts of the positive electrode sheet (cathode electrode sheet) and the negative electrode sheet (anode electrode sheet) with active materials constitute the main body of the battery cell assembly, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute the tab 123a. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery pack 100, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 123a connects the electrode terminal to form a current loop.

[0056] In order to ensure the safe and stable operation of the battery pack, it needs to be waterproof and dustproof, that is, the battery pack should be sealed in theory. However, in the sealed state, once the battery cell of the battery pack 100 is short-circuited or a thermal runaway event occurs, a large amount of gas will be generated, causing the gas pressure inside the box 110 of the battery pack 100 to rise rapidly. If the gas is not exhausted and the pressure is not released in time, it may cause a violent fire or explosion, resulting in serious casualties and property losses. Figure 4 The current existing technical solution is to install an explosion-proof valve 10 that can be opened under the pressure of the gas generated by the battery pack 100 on the box 110 of the battery pack 100 to meet the needs of waterproofing, explosion-proofing, and exhaust pressure relief of the power battery system.

[0057] When the battery is working normally, the exhaust channel of the explosion-proof valve is sealed by the piston pushed by the elastic component. After thermal runaway occurs in the battery pack 100, the gas generated by the thermal runaway overcomes the elasticity of the elastic component and pushes the piston to open the exhaust channel, thereby achieving exhaust pressure relief. The sealing interface between the piston and the valve body is easily invaded by mud and sand outside the battery pack 100. The continuous accumulation of mud and sand will cause the internal sealing interface to fail, thereby losing the waterproof and dustproof functions, and even causing insulation failure or short circuit failure, posing a great threat to the personal and property safety of passengers.

[0058] In order to improve the above problems, this embodiment provides a new explosion-proof valve. Figures 5 to 9 As shown, the explosion-proof valve includes a valve body 5, a piston 7 and a labyrinth sealing structure.

[0059] The valve body 5 is provided with an exhaust hole 51 , and an exhaust outlet of the exhaust hole 51 is arranged on the outer end surface of the valve body 5 .

[0060] The piston 7 is movably covered on the outer end surface of the exhaust channel 51 to switch between a first position closing the exhaust channel 51 and a second position opening the exhaust channel 51. The piston 7 is configured to switch to the second position under the action of the exhaust pressure of the exhaust channel 51.

[0061] The labyrinth sealing structure includes a first annular groove 53 sleeved outside the exhaust outlet of the exhaust channel 51 and an annular protrusion 72 embedded in the first annular groove 53. One of the first annular groove 53 and the annular protrusion 72 is arranged on the outer end surface of the valve body 5, and the other is arranged on the piston 7.

[0062] In this embodiment, the labyrinth sealing structure is sleeved outside the exhaust outlet of the exhaust duct 51, which is beneficial to prevent external debris such as mud and sand from invading the sealing interface formed by the piston 7 and the valve body 5 around the exhaust outlet, and is beneficial to prevent the above-mentioned sealing interface from failing, thereby improving the problem of the above-mentioned debris such as mud and sand affecting the sealing performance of the explosion-proof valve.

[0063] See also Figures 8 to 11 The piston 7 includes a plate-like component 71 which is covered on the outer end surface of the valve body 5 and closes the exhaust outlet of the exhaust channel 51, an annular protrusion 72 is arranged on the side of the plate-like component 71 facing the valve body 5, and a first annular groove 53 is arranged on the outer end surface of the valve body 5. The plate-like component 71 closes the exhaust outlet of the exhaust channel 51 and forms a sealing interface for sealing the exhaust outlet between the valve body 5, and the annular protrusion 72 is embedded in the first annular groove 53 extending along the circumferential direction of the exhaust outlet, thereby lengthening the path for mud and sand to invade the above-mentioned sealing interface, thereby effectively improving the problem that mud and sand and other debris affect the sealing performance of the explosion-proof valve.

[0064] In some embodiments, a groove 54 compatible with the piston 7 is provided on the outer end surface of the valve body 5, the piston 7 is embedded in the groove 54, the first annular groove 53 is provided at the bottom of the groove 54, the above-mentioned annular protrusion 72 invades the first annular groove 53, the plate-like component 71 is located in the above-mentioned groove 54, and the immersion path of mud and other debris between the edge of the plate-like component 71 and the wall of the groove 54 further lengthens the path for mud and sand to invade the above-mentioned sealing interface, thereby effectively preventing mud and other debris from affecting the sealing of the explosion-proof valve.

[0065] In some embodiments, the gap between the annular protrusion 72 and the wall of the first annular groove 53 is less than 2 mm, which is helpful to prevent mud and sand and other debris from penetrating into the above-mentioned sealing interface.

[0066] In some embodiments, the side of the piston 7 facing away from the bottom of the groove 54 is flush with the outer end surface of the valve body 5, which helps prevent mud and other debris from accumulating on the outer end surface of the valve body 5 and reduces the probability of mud and other debris invading the above-mentioned sealing interface.

[0067] In some embodiments, the explosion-proof valve also includes a sealing cover 1 covered on the outer end surface of the valve body 5, and the sealing cover 1 at least covers the groove 54, which is helpful to prevent mud and other debris from adhering to the outer end surface of the valve body 5, thereby reducing the probability of mud and other debris invading the above-mentioned sealing interface.

[0068] In some embodiments, the explosion-proof valve further includes a first sealing ring 9 sleeved outside the exhaust outlet of the exhaust channel 51 and cooperating with the piston 7 to seal the exhaust outlet. A second annular groove matching the first sealing ring 9 is provided on the outer end surface of the valve body 5 (specifically, the bottom surface of the above-mentioned groove 54), and the second annular groove is sleeved outside the exhaust outlet of the exhaust channel 51. The first sealing ring 9 is embedded in the second annular groove, and the piston 7 covering the above-mentioned exhaust outlet abuts against the first sealing ring 9 to seal the exhaust outlet, thereby improving the sealing performance of the explosion-proof valve.

[0069] In some embodiments, the first sealing ring 9 is sleeved in a labyrinth sealing structure, which is helpful to prevent debris such as mud and sand from affecting the sealing performance of the first sealing ring 9.

[0070] In some embodiments, the sealing cover 1 is connected to the piston 7, which is beneficial to reducing the number of parts of the explosion-proof valve and improving assembly efficiency.

[0071] In some embodiments, the sealing cover 1 is bonded to the piston 7. In other embodiments, the sealing cover 1 is connected to the piston 7 by a rubber coating covering the outside of the sealing cover 1 and the piston 7. Optionally, the rubber coating covers the gap between the sealing cover 1 and the piston 7.

[0072] The explosion-proof valve further comprises an elastic pushing mechanism and a protective sleeve 8. The elastic pushing mechanism is configured to push the piston 7 toward the first position, and the protective sleeve 8 is sleeved on the elastic pushing mechanism and is located at the upstream end of the valve body 5 along the exhaust direction of the exhaust channel 51.

[0073] In some embodiments, a mounting hole is provided on the valve body 5, and the elastic pushing mechanism includes a guide rod 2 and an elastic component 3. The guide rod 2 is slidably arranged in the mounting hole, and one end of the guide rod 2 is connected to the piston 7 to move with the piston 7 relative to the valve body 5. The elastic component 3 is configured to elastically push the guide rod 2 and enable the guide rod 2 to drive the piston 7 to move toward the first position.

[0074] In this embodiment, the mounting hole is located in the middle of the valve body 5, and a plurality of exhaust channels 51 are arranged in the circumferential direction of the mounting hole, and the axial direction of the mounting hole is parallel to the extension direction of the exhaust channels 51. The piston 7 moves along the axial direction of the mounting hole with the guide rod 2 to switch between the first position and the second position.

[0075] In some embodiments, a protrusion 21 is provided on the guide rod 2, and the protrusion 21 is located on the side of the valve body 5 away from the piston 7. The elastic component 3 is sleeved on the guide rod 2 and located between the protrusion 21 and the valve body 5. The elastic component 3 is located on the side of the valve body 5 away from the piston 7 and between the protrusion 21 and the valve body 5, so as to push the piston 7 toward the exhaust outlet of the exhaust channel 51 through the guide rod 2 to close the exhaust channel 51.

[0076] The explosion-proof valve further includes a second sealing ring 4 provided on the inner end surface of the valve body 5 for sealing the valve body 5 and the box body 110 of the battery pack 100. The inner end surface and the outer end surface of the valve body 5 are respectively located at the two ends of the valve body 5. The valve body 5 further includes a connecting portion 52, through which the valve body 5 is mounted on the box body 110, and the inner end surface of the valve body 5 abuts against the outer surface of the box body 110. The exhaust channel 51 is communicated with the inner cavity of the box body 110.

[0077] In some embodiments, the explosion-proof valve further includes a driving component 6 for driving the piston 7 toward the second position. When gas is filled into the box body 110 of the battery pack 100 to detect the sealing of the battery pack 100, the piston is opened by the driving component 6 so that gas is filled into the box body 110 from the outside.

[0078] When a large amount of gas is generated in the battery pack due to thermal runaway, the gas in the battery pack pushes the piston 7 to the second position to open the exhaust channel 51, so that the gas in the battery pack is discharged outside the battery pack. Fig.10 and 11 .

[0079] In some embodiments, the driving component 6 includes a magnetic component, such as a thin sheet of steel. The driving component 6 is driven by the magnetic component to move toward the outside of the valve body 5 outside the battery pack 100, and the driving component 6 drives the piston 7 to move toward the second position of opening the exhaust channel 51 outside the valve body 5, thereby opening the exhaust channel.

[0080] In this embodiment, the valve body 5 of the explosion-proof valve is provided with a first annular groove 53; the piston 7 is provided with the above-mentioned annular protrusion 72, and the explosion-proof valve also includes a sealing cover 1 to prevent mud and other debris from entering the inside of the explosion-proof valve. The explosion-proof valve is installed on the box body or box cover of the battery pack through the connecting portion 52 (locking hole) on the valve body 5, and is therefore installed on the box body or box cover of the battery pack using bolts. One end provided with the piston 7 is located outside the battery pack, and one end provided with the protective cover 8 is located inside the battery pack. When thermal runaway occurs, the valve cover of the explosion-proof valve drives the guide rod compression spring to break away from the inner sealing ring and the pressure relief channel is connected, thereby achieving the purpose of rapid pressure relief.

[0081] The above are only exemplary embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An explosion-proof valve, characterized in that: include: The valve body (5) is provided with an exhaust hole (51), wherein an exhaust outlet of the exhaust hole (51) is arranged on an outer end surface of the valve body (5); and a piston (7) movably covering the outer end surface of the exhaust hole (51) so as to switch between a first position closing the exhaust hole (51) and a second position opening the exhaust hole (51), wherein the piston (7) is configured to switch to the second position under the action of the exhaust pressure of the exhaust hole (51); The labyrinth seal structure comprises a first annular groove (53) sleeved outside the exhaust outlet of the exhaust duct (51) and an annular protrusion (72) embedded in the first annular groove (53); one of the first annular groove (53) and the annular protrusion (72) is arranged on the outer end surface of the valve body (5), and the other is arranged on the piston (7).

2. The explosion-proof valve according to claim 1, characterized in that: The piston (7) comprises a plate-like component (71) which is covered on the outer end surface of the valve body (5) and closes the exhaust outlet of the exhaust channel (51); the annular protrusion (72) is arranged on a side of the plate-like component (71) facing the valve body (5); and the first annular groove (53) is arranged on the outer end surface of the valve body (5).

3. The explosion-proof valve according to claim 1, characterized in that: A groove (54) adapted to the piston (7) is provided on the outer end surface of the valve body (5), the piston is embedded in the groove (54), and the first annular groove (53) is provided at the bottom of the groove (54).

4. The explosion-proof valve according to claim 3, characterized in that: A surface of the piston (7) facing away from the bottom of the groove (54) is flush with the outer end surface of the valve body (5).

5. The explosion-proof valve according to claim 3, characterized in that: It also comprises a sealing cover (1) which is arranged on the outer end surface of the valve body (5), the sealing cover (1) being located on a side of the piston (7) away from the valve body (5), and the sealing cover (1) at least covers the groove (54).

6. The explosion-proof valve according to claim 5, characterized in that: The sealing cover (1) is connected to the piston (7).

7. The explosion-proof valve according to claim 6, characterized in that: The sealing cover (1) and the piston (7) are bonded together; or The sealing cover (1) and the piston (7) are connected together via a rubber coating layer covering the outside of both.

8. The explosion-proof valve according to claim 1, characterized in that: It also includes a first sealing ring (9) which is sleeved outside the exhaust outlet of the exhaust channel (51) and cooperates with the piston (7) to seal the exhaust outlet.

9. The explosion-proof valve according to claim 8, characterized in that: The first sealing ring (9) is sleeved in the labyrinth sealing structure.

10. The explosion-proof valve according to claim 1, characterized in that: Also includes: an elastic pushing mechanism, configured to push the piston (7) toward the first position, A protective sleeve (8) is sleeved on the elastic pushing mechanism and is located at the upstream end of the valve body (5) along the exhaust direction of the exhaust channel (51).

11. The explosion-proof valve according to claim 10, characterized in that: The valve body (5) is provided with a mounting hole, and the elastic pushing mechanism comprises: A guide rod (2) is slidably arranged in the mounting hole, one end of the guide rod (2) being connected to the piston (7) so as to move with the piston (7) relative to the valve body (5); The elastic component (3) is configured to elastically push the guide rod (2) and enable the guide rod (2) to drive the piston (7) to move towards the first position.

12. The explosion-proof valve according to claim 11, characterized in that: The guide rod (2) is provided with a protrusion (21), the protrusion (21) is located on a side of the valve body (5) away from the piston (7), and the elastic component (3) is sleeved on the guide rod (2) and located between the protrusion (21) and the valve body (5).

13. The explosion-proof valve according to claim 1, characterized in that: It also includes a driving component (6) for driving the piston (7) towards the second position.

14. The explosion-proof valve according to claim 13, characterized in that: The driving component (6) comprises a magnetic attraction component.

15. A battery pack, characterized in that: The explosion-proof valve comprises the explosion-proof valve according to any one of claims 1 to 14.

16. An electrical device, characterized in that: Includes the battery pack as claimed in claim 15.

Images