Novel explosion-proof valve structure capable of releasing pressure continuously

Abstract

The invention discloses a novel explosion-proof valve structure capable of continuously releasing pressure, which is arranged on a cover plate main body welded with a battery box body so as to seal and cover a blast hole on the cover plate main body, and is characterized in that the explosion-proof valve structure comprises a pressure releasing sleeve piece and a sealing assembly, the pressure relief kit comprises a step sleeve fixedly arranged on the blast hole in an inserted mode and an outer cover arranged on an exposed opening in one end of the step sleeve in a covering mode, and part of the step sleeve is exposed and makes contact with the outside. An air passing cavity for placing the sealing assembly is formed in the stepped sleeve; the air passing cavity is communicated with the interior of the battery box body through an air inlet in the other end of the stepped sleeve and is communicated with the exterior through an exhaust hole in the side wall of the stepped sleeve; according to the technical scheme, the explosion-proof valve is simple in structure, easy to implement and low in cost, and mainly solves the problems that an existing explosion-proof valve structure excessively depends on the quality and the preset pressure value of an explosion-proof piece, only one-time pressure relief can be achieved, and sustainable pressure relief cannot be conducted.

Description

Technical Field

[0001] The invention relates to the technical field of battery cover plates, and in particular to a novel explosion-proof valve structure capable of continuous pressure relief. Background Art

[0002] In order to ensure the safety of power batteries, an explosion-proof valve structure is usually set on the battery cover. After long-term use, a large amount of gas will inevitably accumulate inside the battery, the temperature will rise sharply and high pressure will be generated, which will open the explosion-proof valve structure to release the pressure to prevent the internal high-pressure gas from having nowhere to be released and causing the battery to explode directly.

[0003] However, the existing explosion-proof valve structure mainly uses explosion-proof discs to control the internal pressure of the internal battery. That is, when the internal pressure of the battery reaches the preset pressure value of the explosion-proof disc, the explosion-proof disc will directly burst and detach to open the explosion hole on the battery cover, so that the pressure is released at one time; but this explosion-proof valve structure has the following disadvantages:

[0004] First, the internal pressure threshold of the battery usually has to reach the preset pressure of the explosion-proof plate to open the blasting hole of the battery cover. However, in actual use, in order to reduce costs and prevent the explosion-proof plate from bursting too easily, the preset pressure of the explosion-proof plate is relatively large, and the continuous accumulation of internal pressure in the battery cannot quickly reach the preset value for discharge, and the resulting pressure easily causes the battery to bulge; and if the explosion-proof plate is damaged or fails, the internal pressure will not only cause the battery to bulge, but the battery will also burst directly if the duration is prolonged; therefore, this explosion-proof valve structure is too dependent on the explosion-proof plate, and secondly, this explosion-proof plate is mostly fixed by ultrasonic welding, and the heat generated will directly affect the size of the preset value of the explosion-proof plate. In this way, the preset pressure value and quality of the explosion-proof plate will directly affect the safety of the battery, and the structural performance is not stable enough.

[0005] Secondly, this type of explosion-proof valve can only explode and release pressure under extreme circumstances and is a one-time structure. That is, as long as the internal pressure of the battery accumulates to reach the preset pressure value of the explosion-proof piece, the explosion-proof piece will explode and detach and can no longer be used. Such a structure has a great impact on the service life of the battery.

[0006] Thirdly, the explosion-proof valve structure is extremely troublesome to disassemble and assemble. For example, when there is insufficient electrolyte inside the battery, the secondary injection operation is difficult to achieve.

[0007] In summary, the existing explosion-proof valve structure still needs to be further improved to meet actual use requirements. Summary of the invention

[0008] The present invention provides a novel explosion-proof valve structure with continuous pressure relief, which is simple in structure, easy to implement and low in cost. It mainly solves the problem that the existing explosion-proof valve structure is too dependent on the quality of the explosion-proof disk and the preset pressure value, and can only relieve pressure once and cannot relieve pressure continuously. The main technical methods are as follows:

[0009] A novel explosion-proof valve structure with continuous pressure relief is installed on a cover plate body welded to a battery box body to seal the explosion hole on the cover plate body, and is characterized in that: the explosion-proof valve structure includes a pressure relief kit and a sealing component; wherein the pressure relief kit includes a stepped sleeve fixedly mounted on the explosion hole, and an outer cover covering an exposed opening at one end of the stepped sleeve, wherein the stepped sleeve is partially exposed and in contact with the outside; the stepped sleeve has an air passage cavity inside for placing the sealing component; the air passage cavity is connected to the inside of the battery box body through an air inlet at the other end of the stepped sleeve, and the air inlet at the other end of the stepped sleeve is connected to the inside of the battery box body, and the air inlet at the other end of the stepped sleeve is connected to the inside of the battery box body. The exhaust hole through the side wall of the step sleeve is connected to the outside; a sealing assembly includes a sealing gasket and a supporting spring arranged in the air cavity; the supporting spring is axially arranged on the outer cover through a limiting structure, and its axis is parallel to the axis of the step sleeve; the supporting spring is axially supported on the end face of the sealing gasket, driving the sealing gasket to axially displace and form a seal with the inner wall surface of the step sleeve to close the air inlet; the internal air pressure of the battery box body acts on the sealing gasket, driving the supporting spring to axially compress or reset, so as to link the sealing gasket to open and close the air inlet.

[0010] Preferably, a limit stop ring is formed on the inner wall of the step sleeve, and the limit stop ring is located at the air inlet; a waterproof and breathable membrane is welded on the limit stop ring, and a pressure relief space is formed between the waterproof and breathable membrane and the air cavity, and the air pressure inside the battery box body can enter the air cavity through the waterproof and breathable membrane and the pressure relief space in sequence.

[0011] Preferably, the limiting structure is a limiting hole arranged at the center of the inner end surface of the outer cover; the supporting spring is axially inserted into the limiting hole, so that the outer peripheral wall of the supporting spring part is in contact with the wall of the limiting hole, constraining the supporting spring to move in the radial direction, so as to limit the axis of the supporting spring to be parallel to the axis of the step sleeve.

[0012] Preferably, the diameter of the limiting hole is less than or equal to the diameter of the holding spring.

[0013] Preferably, the sealing gasket is configured as a soft sealing gasket, and the supporting spring is configured as a V-shaped supporting spring; the top of the supporting spring is inserted into the limiting hole, and the bottom of the supporting spring acts on the end face of the sealing gasket; when the air pressure inside the battery box acts on the sealing gasket, the sealing gasket presses against the bottom of the supporting spring to be softly deformed and can swing to open the air inlet.

[0014] Preferably, the sealing gasket also includes an integrally formed disc portion and an annular portion; the outer circumference of the disc portion is inclined and chamfered, and the inner wall surface of the step sleeve is formed with an inclined platform; the supporting spring can axially pass through the inner cavity of the annular portion and support the end surface of the disc portion, driving the outer circumference of the disc portion to tightly adhere to the wall surface of the inclined platform to form a sloped fitting seal.

[0015] Preferably, the sealing gasket also includes an integrally formed disc portion and an annular portion; the outer circumference of the disc portion is inclined and chamfered, and the inner wall surface of the step sleeve is formed with an inclined platform; the supporting spring can axially pass through the inner cavity of the annular portion and support the end surface of the disc portion, driving the outer circumference of the disc portion to tightly adhere to the wall surface of the inclined platform to form a sloped fitting seal.

[0016] Preferably, a mounting groove is formed on the cover plate body, and a sealing ring is provided in the mounting groove; the thickness of the sealing ring is higher than the groove depth of the mounting groove; when the stepped sleeve is inserted into the blasting hole, the stepped sleeve acts on the sealing ring and presses the thickness of the sealing ring to be equal to the groove depth of the mounting groove.

[0017] Preferably, the stepped sleeve is detachably screwed into the blasting hole.

[0018] Preferably, the side wall of the step sleeve is provided with a plurality of exhaust holes, and the exhaust holes are arranged at equal intervals around the outer peripheral wall of the step sleeve.

[0019] It can be seen from the above description of the present invention that, compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The present invention provides a new explosion-proof valve structure with continuous pressure relief, which has a simple structure, is easy to implement and has low cost. It mainly solves the problem that the existing explosion-proof valve structure is too dependent on the quality of the explosion-proof plate and the preset pressure value, and can only relieve pressure once, and cannot relieve pressure continuously. The technical solution of the present invention mainly replaces the existing explosion-proof plate by the cooperation of a holding spring and a sealing gasket. When the air pressure inside the battery box increases, and the force of the air pressure acting on the sealing gasket is greater than the holding elastic force of the holding spring acting on the sealing gasket, the air pressure can drive the sealing gasket to link with the holding spring to compress, open the air inlet, and allow the air pressure to enter the air cavity and discharge the pressure continuously through the exhaust hole; when the air pressure inside the battery box is relatively low, and the force of the air pressure acting on the sealing gasket is less than the holding elastic force of the holding spring acting on the sealing gasket, the holding spring returns to normal and the air inlet is closed. Therefore, in the present technical solution, as long as the air pressure generated inside the battery box is greater than the holding force of the holding spring, the gas can be gradually and continuously discharged to the outside through the air inlet. There is no need to use disposable explosion-proof plates for exhaust and worry about increasing costs. No pressure will be stored inside, which can not only extend the service life of the explosion-proof valve structure, but also effectively prevent the battery from bulging. Moreover, the explosion-proof valve structure in the present technical solution can maintain the sustainable exhaust function while also being able to quickly explode and release pressure instantly when facing the instantaneous high-pressure gas inside the battery. It also has the instantaneous pressure relief function of the existing explosion-proof plates, and has both sustainable pressure relief and instantaneous pressure relief functions, which greatly extends the service life of the power battery.

[0021] (2) In the present technical solution, a holding spring with very small holding force can be selectively selected, so that even if the air pressure reaches a relatively small value, it can still be discharged. In this way, the pressure inside the battery box will not accumulate to the critical value that the battery can withstand, which makes it easier to carry out sustainable pressure relief and effectively protect the battery.

[0022] (3) Compared with the existing explosion-proof plates, the high temperature generated by welding during the welding and fixing process will affect the size of the preset value of the explosion-proof plate, resulting in the problem of unstable blasting function of the product; in this technical solution, the holding spring is not affected by temperature and has a low replacement cost. Various sizes of holding springs can be used. According to the explosion value requirements, it can be applied to various usage scenarios, providing more market choices.

[0023] (4) In the present technical solution, a pressure-relief space is provided between the waterproof breathable membrane and the air cavity, so that after the gas passes through the waterproof breathable membrane, a certain pressure relief buffer can be performed in the pressure-relief space, and the gas will not act quickly on the sealing gasket, causing the sealing gasket to instantly bounce and displace under the action of the holding spring, thereby affecting the service life of the holding spring. In addition, the design of the pressure-relief space also facilitates the accumulation of gas therein. For example, if the actual holding force of the holding spring is designed to be too high, and the pressure of the internal gas is less than the holding force and the air inlet cannot be opened, the gas can enter the pressure-relief space through the waterproof breathable membrane and be accumulated. When a sufficient amount of gas is accumulated, a sufficient pressure can be generated to open the air inlet. Therefore, even if the holding spring is selected with incorrect specifications, there is no need to worry too much about the inability to continuously relieve pressure. The continuous pressure relief function of the product is extremely stable.

[0024] (5) In the present technical solution, the setting of the limiting structure effectively prevents the supporting spring from being non-parallel to the axis of the step sleeve, so that the axial displacement of the supporting spring will be tilted and the elastic supporting force will be blocked and reduced.

[0025] (6) In the present technical solution, the sealing gasket is configured as a soft sealing gasket, and the holding spring is configured as a V-shaped holding spring; thus, even if the pressure inside the battery case is less than the holding elastic force of the holding spring, the pressure acting on the soft sealing gasket can drive it to deform slightly and open part of the air inlet, thereby further ensuring that the product's continuous pressure relief function tends to be stable.

[0026] (7) The stepped sleeve is detachably screwed into the blasting hole, so that the explosion-proof valve structure is extremely convenient to disassemble and assemble. If the electrolyte inside the battery is insufficient and needs secondary injection or needs to be repaired or replaced, this connection method is very easy to achieve. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0028] Figure 1 This is a schematic diagram of the structure of the explosion-proof valve structure of an embodiment of the present invention installed on an existing cover plate body;

[0029] Figure 2 for Figure 1 The overall exploded diagram of

[0030] Figure 3 for Figure 1 Exploded cross-sectional view;

[0031] Figure 4The explosion-proof valve structure of the embodiment of the present invention is installed on the existing cover plate body. Figure 1 ;

[0032] Figure 5 The explosion-proof valve structure of the embodiment of the present invention is installed on the existing cover plate body. Figure 2 .

[0033] The following are the descriptions of the reference numerals:

[0034] 1. Cover plate body; 11. Blasting hole; 12. Installation slot;

[0035] 2. Explosion-proof valve structure; 21. Pressure relief kit; 211. Step sleeve; 211A. Air inlet; 211B. Exhaust hole; 211C. Stop ring; 211D. Tilt table; 212. Outer cover; 213. Air passage cavity; 22. Sealing assembly; 221. Sealing pad; 221A. Disc portion; 221B. Ring portion; 222. Holding spring;

[0036] 3. Limiting structure;

[0037] 4. Waterproof and breathable membrane; 5. Pressure relief space; 6. Sealing ring. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are preferred embodiments of the present invention and should not be regarded as excluding other embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] In the claims, description and the above-mentioned drawings of the present invention, unless otherwise clearly defined, the use of terms such as "first", "second" or "third" etc. are for distinguishing different objects rather than for describing a specific order.

[0040] In the claims, specification and the above-mentioned drawings of the present invention, unless otherwise explicitly defined, directional words, such as the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the specific protection scope of the present invention.

[0041] In the claims, specification and the above drawings of the present invention, unless otherwise clearly defined, if the term "fixed connection" or "fixed connection" is used, it should be understood in a broad sense, that is, any connection method without a displacement relationship and relative rotation relationship between the two, that is to say, including non-detachable fixed connection, detachable fixed connection, integrated connection and fixed connection through other devices or elements.

[0042] In the claims, description and drawings of the present invention, if the terms "include", "have" and their variations are used, they are intended to mean "including but not limited to".

[0043] See also Figures 1 to 5 .

[0044] The present embodiment provides a novel explosion-proof valve structure 2 for continuous pressure relief, which is simple in structure, easy to implement and low in cost. It mainly solves the problem that the existing explosion-proof valve structure 2 is too dependent on the quality of the explosion-proof disk and the preset pressure value, and can only relieve pressure once and cannot relieve pressure continuously. The structure of the present embodiment mainly includes a pressure relief kit 21 and a sealing assembly 22; see Figures 2 to 4 The explosion-proof valve structure 2 is mounted on the cover plate body 1 welded to the battery box body (not shown) to cover the explosion hole 11 on the cover plate body 1; wherein,

[0045] The pressure relief kit 21 includes a stepped sleeve 211 inserted and fixed on the blasting hole 11, and an outer cover 212 covering the exposed opening at one end of the stepped sleeve 211, and the stepped sleeve 211 is partially exposed and in contact with the outside; the stepped sleeve 211 has an air cavity 213 inside for placing the sealing component 22; the air cavity 213 is connected to the inside of the battery box through an air inlet 211A at the other end of the stepped sleeve 211, and is connected to the outside through an exhaust hole 211B on the side wall of the stepped sleeve 211; a plurality of exhaust holes 211B are provided, and each exhaust hole 211B is arranged at equal intervals around the outer peripheral wall of the stepped sleeve 211, so as to improve the pressure relief and exhaust efficiency and prevent a large amount of gas from accumulating inside the air cavity 213.

[0046] In this embodiment, the stepped sleeve 211 is a stepped sleeve; the air cavity 213 connects the interior and exterior of the battery box at the same time, so that the air cavity 213 is used to receive the gas flowing into the battery box, and then allow the gas to be discharged to the outside after passing through it. That is, due to the high pressure generated inside the battery box, when the battery box is connected to the outside through the air cavity 213, the gas flows rapidly from the high pressure direction to the low pressure direction and is automatically discharged to the outside.

[0047] In this embodiment, the exposed opening at one end of the stepped sleeve 211 faces the outside, and the air inlet 211A at the other end faces the inside of the battery box body; the opening cover is provided with an outer cover 212. During actual installation, the sealing assembly 22 can be placed in the air cavity 213 by opening the outer cover 212, which is convenient for production and installation.

[0048] In this embodiment, the outer periphery of the stepped sleeve 211 and the inner wall of the blasting hole 11 are provided with matching threads (not shown), and the stepped sleeve 211 is detachably screwed into the blasting hole 11, so that the explosion-proof valve structure 2 is extremely convenient to disassemble and assemble. If the electrolyte inside the battery is insufficient and a secondary injection operation is required or it needs to be repaired or replaced, this connection method is very easy to achieve. In other embodiments, the stepped sleeve 211 and the blasting hole 11 can also be welded or riveted.

[0049] Since the step sleeve 211 and the cover plate body 1 are installed and connected by screw connection, there are certain requirements for sealing. In this embodiment, a mounting groove 12 is formed on the cover plate body 1, and a sealing ring 6 (the sealing ring 6 is rubber) is arranged in the mounting groove 12; the thickness of the sealing ring 6 is higher than the groove depth of the mounting groove 12; when the step sleeve 211 is inserted into the blasting hole 11, the step sleeve 211 acts on the sealing ring 6, and presses the thickness of the sealing ring 6 to be equal to the groove depth of the mounting groove 12, so that the mounting groove 12 can not only be used to place the sealing ring 6, but its groove depth design can also control the compression of the sealing ring 6, avoiding the phenomenon of overpressure and insufficient compression of the sealing ring 6 during production and subsequent replacement, and the sealing is guaranteed. Other embodiments such as welding or riveting can also adopt such a design to prevent air leakage in the explosion-proof valve.

[0050] The sealing component 22 is used to open and close the air cavity 213 and the air inlet 211A connected to the inside of the battery box; the sealing component 22 includes a sealing gasket 221 and a supporting spring 222 arranged in the air cavity 213; the supporting spring 222 is axially arranged on the outer cover 212 through the limiting structure 3, and its axis is parallel to the axis of the step sleeve 211; the supporting spring 222 is axially supported on the end face of the sealing gasket 221, driving the sealing gasket 221 to move axially to form a seal with the inner wall of the step sleeve 211 to close the air inlet 211A.

[0051] When the gas accumulated inside the battery box generates high pressure, the high-pressure gas will act on the sealing gasket 221, driving the supporting spring 222 to axially compress, and linking the sealing gasket 221 to open the air inlet 211A, at which time continuous pressure relief and exhaust can be carried out; when the gas accumulated pressure inside the battery box is relatively small, the gas will also act on the sealing gasket 221, but the gas pressure is less than the supporting elastic force of the supporting spring 222, so the supporting spring 222 will reset axially to link the sealing gasket 221 to close the air inlet 211A.

[0052] The specific principle of the sealing gasket 221 opening and closing the air inlet 211A is as follows: when the air pressure inside the battery box increases and the force of the air pressure on the sealing gasket 221 is greater than the elastic force of the supporting spring 222 on the sealing gasket 221, the air pressure can drive the sealing gasket 221 to link with the supporting spring 222 to be compressed, thereby opening the air inlet 211A and allowing the air pressure to enter the air cavity 213 and be continuously discharged through the exhaust hole 211B to release the pressure; when the air pressure inside the battery box is relatively low and the force of the air pressure on the sealing gasket 221 is less than the elastic force of the supporting spring 222 on the sealing gasket 221, the supporting spring 222 returns to normal and the air inlet 211A is closed.

[0053] In this embodiment, the supporting spring 222 is a common cylindrical spring, and an axis is formed at its center position; the limiting structure 3 is a limiting hole provided at the center of the inner end surface of the outer cover 212. When the supporting spring 222 is inserted into the limiting hole through the axial direction of the axis, the supporting spring 222 will be vertically arranged at the center of the outer cover 212. In this way, part of the outer peripheral wall of the supporting spring 222 will be in contact with the wall of the limiting hole, and the supporting spring 222 will be constrained to move in the radial direction, so as to limit the axis of the supporting spring 222 to be parallel to the axis of the step sleeve 211, and effectively prevent the supporting spring 222 from being non-parallel to the axis of the step sleeve 211, and the axial displacement of the supporting spring 222 will be tilted and the elastic supporting force will be blocked and reduced. Of course, in other embodiments, the limiting structure 3 can also be a columnar body, that is, the columnar body extends upward from the center of the outer cover 212, and the supporting spring 222 is just set in the columnar body, so that the radial constraint of the supporting spring 222 can also be achieved.

[0054] In this embodiment, the diameter of the limiting hole is less than or equal to the diameter of the cylindrical supporting spring 222; when the diameter of the limiting hole is equal to the diameter of the cylindrical supporting spring 222, the walls of the two can just contact each other, thereby achieving a radial constraint effect; and when the diameter of the limiting hole is smaller than the diameter of the cylindrical supporting spring 222, due to the elasticity of the spring itself, the bottom of the supporting spring 222 is deformed and contracted in the radial direction to cooperate with the limiting hole, so that not only can the walls of the two be in contact with each other, but they can also generate mutual force to tighten, preventing the supporting spring 222 from being out of position, and further ensuring that the axis of the supporting spring 222 is parallel to the axis of the step sleeve 211.

[0055] In this embodiment, the sealing gasket 221 is configured as a soft or hard sealing gasket 221; in this embodiment, the hard sealing gasket 221 is taken as an example. Since the supporting spring 222 is an ordinary spring, it has elasticity but also has a certain hardness. When the sealing gasket 221 also has a certain hardness, (see Figure 4) is not restricted by the shape and structure of the supporting spring 222. The sealing gasket 221 is affected by the gas inside the battery box, and the axial compression or reset of the supporting spring 222 will move straight up and down. Similarly, if the sealing gasket 221 is also made of soft material, although it can also move straight up and down, if the shape and structure of the supporting spring 222 changes, the displacement may change.

[0056] For further information, see Figure 4 and Figure 5 The holding spring 222 is configured as a V-shaped holding spring 222, and the sealing gasket 221 is a soft sealing gasket 221; during assembly, the top (larger diameter) of the holding spring 222 is inserted into the limiting hole, and the bottom (smaller diameter) thereof acts on the end surface of the sealing gasket 221; when the air pressure inside the battery box acts on the sealing gasket 221, see Figure 5 The sealing gasket 221 is pressed against the bottom of the supporting spring 222 (as a fulcrum) and is softly deformed and can swing to open the air inlet 211A. In this way, even if the pressure inside the battery box is less than the supporting elastic force of the supporting spring 222, the pressure acting on the soft sealing gasket 221 can also drive it to deform slightly and open part of the air inlet 211A, thereby further ensuring that the product's continuous pressure relief function tends to be stable.

[0057] In this embodiment, see Figure 3 and Figure 4 The sealing gasket 221 also includes an integrally formed disc portion 221A and an annular portion 221B; the outer circumference of the disc portion 221A is inclined and chamfered, and an inclined platform 211D is formed on the inner wall of the stepped sleeve 211; the supporting spring 222 can axially pass through the inner cavity of the annular portion 221B and be supported on the end surface of the disc portion 221A, driving the outer circumference of the disc portion 221A to be tightly attached to the wall surface of the inclined platform 211D to form an inclined surface matching seal. Such a reasonable structural design is more conducive to saving the internal space of the air cavity 213.

[0058] In this embodiment, the outer periphery of the disc portion 221A is tightly attached to the wall surface of the tilting platform 211D to form a bevel fitting seal, which is the first seal; the outer diameter of the annular portion 221B is equal to the inner diameter of the air cavity 213, and when the supporting spring 222 is axially compressed, the outer wall surface of the annular portion 221B can be tightly attached to the exhaust hole 211B on the side wall of the step sleeve 211 to seal the exhaust hole 211B, which is the second seal; when the supporting spring 222 is axially reset, the outer wall surface of the annular portion 221B can be displaced from the exhaust hole 211B on the side wall of the step sleeve 211 to open the exhaust hole 211B. Therefore, when the supporting spring 222 is axially compressed, the air inlet 211A and the exhaust hole 211B are opened at the same time; when the supporting spring 222 is axially reset, the air inlet 211A and the exhaust hole 211B are closed at the same time; in this way, when the battery box body is not vented, the air cavity 213 is closed from the outside, which can effectively prevent external dust and liquid from entering.

[0059] In this embodiment, see Figure 3 and Figure 4 A limit stop ring 211C is formed on the inner wall of the step sleeve 211, and the limit stop ring 211C is located at the air inlet 211A; a waterproof and breathable membrane 4 is welded on the limit stop ring 211C, and a pressure relief space 5 is formed between the waterproof and breathable membrane 4 and the air cavity 213. The internal air pressure of the battery box can enter the air cavity 213 through the waterproof and breathable membrane 4 and the pressure relief space 5 in sequence.

[0060] In this embodiment, the waterproof breathable membrane 4 is a unidirectional waterproof breathable membrane 4, which is an existing design product. This embodiment mainly applies it directly, and the specific structure is not repeated. Therefore, in this embodiment, external gas, liquid and other substances cannot enter the battery through the exhaust hole 211B, the air cavity 213, and the air inlet 211A to cause an impact; and considering that the entire explosion-proof valve body may not be able to keep up with the gas production speed of the battery in normal exhaust under extreme conditions, the waterproof breathable membrane 4 is designed to allow rupture under a certain air pressure to help exhaust.

[0061] In the present embodiment, a pressure relief space 5 is provided between the waterproof breathable membrane 4 and the air cavity 213, so that after the gas passes through the waterproof breathable membrane 4, a certain pressure relief buffer can be performed in the pressure relief space 5, and the gas will not act quickly on the sealing pad 221, causing the sealing pad 221 to bounce and displace instantly under the action of the supporting spring 222, thereby affecting the service life of the supporting spring 222; moreover, the design of the pressure relief space 5 is also convenient for gas to be accumulated therein. For example, if the supporting force of the supporting spring 222 is actually designed to be too high, and the pressure of the internal gas is less than the supporting force and cannot open the air inlet 211A, at this time, the gas passes through the waterproof breathable membrane 4 into the pressure relief space 5 and can be accumulated. When the accumulated amount is sufficient, it can generate a sufficiently large pressure to open the air inlet 211A; therefore, even if the supporting spring 222 is selected with incorrect specifications, there is no need to worry too much about the inability to continuously relieve pressure, and the continuous pressure relief function of the product is extremely stable.

[0062] In this embodiment, the material selection for the pressure relief kit 21 can be based on actual needs, such as aluminum, steel, etc.; and the main material screw connection method in this embodiment has lower requirements for material selection and correspondingly lower costs.

[0063] The working principle and use process of the present invention:

[0064] When assembling, refer to Figure 3 and Figure 4 ; First, place the sealing ring 6 in the mounting groove 12 of the cover body 1; second, open the outer cover 212, and place the sealing gasket 221 in the air cavity 213, so that the outer periphery of the disc portion 221A of the sealing gasket 221 is tightly attached to the wall surface of the inclined platform 211D of the stepped sleeve 211; third, vertically arrange the supporting spring 222 in the center of the outer cover 212, so that the outer peripheral wall of part of the supporting spring 222 is in contact with the wall of the limiting hole, so that the supporting spring 222 will not move in the radial direction (the supporting spring 222 can be pre-positioned after being arranged in the limiting hole in the center of the outer cover 212, and then the two are connected and fixed by ultrasonic welding); fourth, cover the outer cover 212 on the exposed opening of the stepped sleeve 211 (the outer cover 212 and the opening can be screwed together). Fifth, the waterproof and breathable membrane 4 is ultrasonically welded to the limit retaining ring 211C of the inner wall of the step sleeve 211; at this time, the assembly of the entire explosion-proof valve structure 2 is completed, and the outer periphery of the step sleeve 211 and the inner wall of the blasting hole 11 are screwed and tightened, wherein the step sleeve 211 acts on the sealing ring 6, and the thickness of the sealing ring 6 is pressed to be equal to the groove depth of the mounting groove 12, completing the constraint and fixation of the explosion-proof valve structure 2 and the cover plate body 1; finally, the cover plate body 1 is welded to the battery box body.

[0065] In actual use, when the gas inside the battery box accumulates and generates high pressure, the high-pressure gas will act on the sealing gasket 221, drive the holding spring 222 to axially compress, and link the sealing gasket 221 to open the air inlet 211A, and then continuous pressure relief and exhaust can be performed; when the pressure of the gas inside the battery box is relatively small, the gas will also act on the sealing gasket 221, but the pressure of the gas is less than the holding elastic force of the holding spring 222, so the holding spring 222 will be axially reset to close the air inlet 211A with the sealing gasket 221. If the gas inside the battery box accumulates rapidly and generates instantaneous high pressure, the high pressure will quickly act on the sealing gasket 221 and the holding spring 222, and the outer cover 212 will quickly explode and release pressure instantly, and also has the instantaneous pressure relief function of the existing explosion-proof disc. Therefore, the present invention has a simple structure, is easy to implement and has low cost, and mainly solves the problem that the existing explosion-proof valve structure 2 is too dependent on the quality of the explosion-proof disc and the preset pressure value, and can only release pressure once, and cannot release pressure continuously. The technical solution of the present invention mainly replaces the existing explosion-proof plate by the cooperation of the supporting spring 222 and the sealing gasket 221. When the air pressure inside the battery box body increases and the force of the air pressure acting on the sealing gasket 221 is greater than the supporting elastic force of the supporting spring 222 acting on the sealing gasket 221, the air pressure can drive the sealing gasket 221 to link with the supporting spring 222 to be compressed, and the air inlet 211A is opened to allow the air pressure to enter the air cavity 213 and be continuously discharged and relieved through the exhaust hole 211B; when the air pressure inside the battery box body is relatively low and the force of the air pressure acting on the sealing gasket 221 is less than the supporting elastic force of the supporting spring 222 acting on the sealing gasket 221, the supporting spring 222 returns to normal and the air inlet 211A is closed. Therefore, in the present technical solution, as long as the air pressure generated inside the battery box is greater than the holding force of the holding spring 222, the gas can be gradually and continuously discharged to the outside through the air inlet 211A. There is no need to use disposable explosion-proof plates for exhaust and worry about increasing costs. No pressure will be stored inside, which can not only extend the service life of the explosion-proof valve structure 2, but also effectively prevent the battery from bulging. Moreover, the explosion-proof valve structure 2 in the present technical solution can maintain the sustainable exhaust function while also being able to quickly explode and release pressure instantly when facing the instantaneous high-pressure gas inside the battery. It also has the instantaneous pressure relief function of the existing explosion-proof plates, and has both sustainable pressure relief and instantaneous pressure relief functions, which greatly extends the service life of the power battery.

[0066] The description of the above specification and embodiments is used to explain the protection scope of the present invention, but does not constitute a limitation on the protection scope of the present invention. Through the enlightenment of the present invention or the above embodiments, ordinary technicians in this field can obtain modifications, equivalent substitutions or other improvements to the embodiments of the present invention or part of the technical features thereof through logical analysis, reasoning or limited experiments, which should be included in the protection scope of the present invention.

Claims

1. A novel explosion-proof valve structure capable of continuous pressure relief, which is installed on a cover plate body welded to a battery box body to seal the explosion hole on the cover plate body, characterized in that: The explosion-proof valve structure includes a pressure relief kit and a sealing assembly; wherein, A pressure relief kit, comprising a stepped sleeve inserted and fixedly mounted on the blasting hole, and an outer cover covering an exposed opening at one end of the stepped sleeve, wherein a portion of the stepped sleeve is exposed and in contact with the outside; the stepped sleeve has an air passage cavity inside for placing the sealing component; the air passage cavity is connected to the inside of the battery box through an air inlet at the other end of the stepped sleeve, and is connected to the outside through an exhaust hole on the side wall of the stepped sleeve; A sealing assembly, comprising a sealing gasket and a holding spring disposed in the air passage cavity; the holding spring is axially disposed on the outer cover through a limiting structure, and its axis is parallel to the axis of the stepped sleeve; the holding spring is axially held on the end surface of the sealing gasket, driving the sealing gasket to move axially to form a seal with the inner wall surface of the stepped sleeve, so as to close the air inlet; The air pressure inside the battery box acts on the sealing gasket, driving the supporting spring to axially compress or reset, thereby linking the sealing gasket to open and close the air inlet.

2. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 1, characterized in that: A limit stop ring is formed on the inner peripheral wall of the stepped sleeve, and the limit stop ring is located at the air inlet; a waterproof and breathable membrane is welded on the limit stop ring, and a pressure relief space is formed between the waterproof and breathable membrane and the air cavity, and the air pressure inside the battery box body can enter the air cavity through the waterproof and breathable membrane and the pressure relief space in sequence.

3. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 2, characterized in that: The limiting structure is a limiting hole arranged at the center of the inner end surface of the outer cover; the supporting spring is axially inserted into the limiting hole, so that the outer peripheral wall of the supporting spring part is in contact with the wall of the limiting hole, restricting the supporting spring from moving in the radial direction to limit the axis of the supporting spring to be parallel to the axis of the step sleeve.

4. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 3, characterized in that: The diameter of the limiting hole is less than or equal to the diameter of the supporting spring.

5. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 3, characterized in that: The sealing gasket is configured as a soft sealing gasket, and the supporting spring is configured as a V-shaped supporting spring; the top of the supporting spring is inserted into the limiting hole, and the bottom of the supporting spring acts on the end surface of the sealing gasket; when the air pressure inside the battery box body acts on the sealing gasket, the sealing gasket presses against the bottom of the supporting spring to be softly deformed and can swing to open the air inlet.

6. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 5, characterized in that: The sealing gasket also includes an integrally formed disc portion and an annular portion; the outer circumference of the disc portion is inclined and chamfered, and the inner wall surface of the stepped sleeve is formed with an inclined platform; the supporting spring can axially pass through the inner cavity of the annular portion and support the end surface of the disc portion, driving the outer circumference of the disc portion to be tightly attached to the wall surface of the inclined platform to form an inclined surface fitting seal.

7. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 6, characterized in that: When the supporting spring is axially compressed, the outer wall surface of the annular portion can be tightly positioned relative to the exhaust hole of the side wall of the step sleeve to seal the exhaust hole; when the supporting spring is axially reset, the outer wall surface of the annular portion can be misaligned with the exhaust hole of the side wall of the step sleeve to open the exhaust hole.

8. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 1, characterized in that: A mounting groove is formed on the cover plate body, and a sealing ring is arranged in the mounting groove; the thickness of the sealing ring is higher than the groove depth of the mounting groove; when the stepped sleeve is inserted into the blasting hole, the stepped sleeve acts on the sealing ring and presses the thickness of the sealing ring to be equal to the groove depth of the mounting groove.

9. A novel explosion-proof valve structure with continuous pressure relief as claimed in any one of claims 1 to 8, characterized in that: The stepped sleeve is detachably screwed into the blasting hole.

10. A novel explosion-proof valve structure capable of continuous pressure relief as claimed in claim 1, characterized in that: The side wall of the step sleeve is provided with a plurality of exhaust holes, and each of the exhaust holes is arranged at equal intervals around the outer peripheral wall of the step sleeve.

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