Pressure Relief Device

Abstract

To provide a pressure relief device that discharges gas accumulated in a battery pack if pressure is higher than a predetermined value.SOLUTION: A pressure relief device 101 comprises a mounting seat 3505, a valve core 3504, and a pressure relief member 3502, where the mounting seat 3505 is internally provided with a fluid channel 3401 and the fluid channel 3401 is capable of communicating with an internal space of a component to be subject to pressure relief. The valve core 3504 is arranged to be aligned with the fluid channel 3401 in the mounting seat 3505 and a pressure relief channel 3402 is formed between an outer edge of the valve core 3504 and an inner wall of the fluid channel 3401 of the mounting seat 3505. The pressure relief member 3502 is sleeved on the outer edge of the valve core 3504. The pressure relief member 3502 opens and closes the pressure relief channel 3402 by means of its deformation.SELECTED DRAWING: Figure 3A

Description

[Technical Field]

[0001] The present application relates to a pressure relief device, and more particularly to a pressure relief device for a battery pack. [Background technology]

[0002] Batteries generate gas during use. If the gas is not released in a timely manner and accumulates inside the battery pack, the pressure inside the battery pack will increase, affecting the use of the battery pack. Therefore, when manufacturing a battery, it is often necessary to attach a pressure relief device to the battery pack. When the pressure inside the battery pack exceeds a predetermined value, the pressure relief device can automatically open to release the gas accumulated inside the battery pack and relieve the internal excess pressure. Summary of the Invention

[0003] The present application provides a pressure relief device comprising a mounting base, a valve core, and a pressure relief member. The mounting base has a fluid passage therein, which is capable of communicating with the interior space of the component to be pressure-relieved. The valve core is positioned to align with the fluid passage in the mounting base, and a pressure relief passage is formed between the outer edge of the valve core and the inner wall of the fluid passage in the mounting base. The pressure relief member is placed over the outer edge of the valve core. The pressure relief member is deformable and configured to open and close the pressure relief passage by its deformation. In the present application, by providing the pressure relief member on the outside of the valve core of the pressure relief device and utilizing the deformability of the pressure relief member itself, the pressure relief device can achieve repeated use and multiple pressure relief effects.

[0004] In the above-described pressure release device, the pressure release member has a pressure receiving side, and can be configured to have a closing operation state in which the pressure release passage is closed, and an opening operation state, and when the pressure on the pressure receiving side of the pressure release member exceeds a predetermined value, the pressure release member deforms and changes from the closing operation state to the opening operation state in which the pressure release passage is open, and when the pressure on the pressure receiving side of the pressure release member becomes less than the predetermined value, the pressure release member returns to the closing operation state.

[0005] In the pressure relief device described above, the pressure relief member is made of a material having deformation properties.

[0006] In the above-mentioned pressure relief device, the valve core has a circular cross section, and the pressure relief member is in the form of a ring, and the pressure relief member has an inner edge and an outer edge, the inner edge being connected to the valve core and the outer edge abutting the mounting base in a free state to close the pressure relief passage.

[0007] In the pressure relief device described above, the pressure relief member extends outwardly and downwardly from the inner edge to the outer edge.

[0008] In the pressure relief device described above, the valve core is made of plastic, and the pressure relief member is fixed to the outer surface of the valve core by a molding process.

[0009] In the above-mentioned pressure relief device, the valve core is provided with a valve core through-hole, and the pressure relief device further comprises a waterproof gas-permeable membrane that covers the valve core through-hole of the valve core so that gas from the pressure relief passage can be released to the external environment through the waterproof gas-permeable membrane.In the above-mentioned pressure relief device, the pressure relief device further comprises a protective cover that is provided with a protective cover through-hole, and the protective cover is snap-fastened onto the mounting base, so that the valve core and the pressure relief member are accommodated in a space formed by the mounting base and the protective cover.

[0010] The pressure release device further includes a sealing ring, and the mounting base has at least one opening formed in a position close to the pressure release member, so that when the outer edge of the pressure release member is bent upward, gas flowing between the outer edge of the pressure release member and the inner wall of the fluid passage can be released to the external environment through the at least one opening.

[0011] In the above-mentioned pressure relief device, the pressure relief device is used in a battery pack, the battery pack includes a battery pack housing, the battery pack housing is provided with a mounting hole, and the pressure relief device is attached to the battery pack housing through the mounting hole.

[0012] In the present application, the pressure release member is disposed within the pressure release device, and the elasticity of the pressure release member itself is used to open and close the pressure release passage within the pressure release device, thereby achieving the effect of concentrated pressure release of the pressure release device. The elasticity of the pressure release member allows the pressure release member to return to its initial state in a timely manner, and the existing structure of the pressure release device is not destroyed each time pressure is released, so that the pressure release device of the present application can achieve the effect of concentrated pressure release multiple times and can be used repeatedly in the battery pack, thereby greatly reducing the cost of using the pressure release device. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a battery pack 100 using a pressure relief device 101 according to an embodiment of the present application. [Figure 2A] 2 is a partial perspective view of a pressure release device 101 and a top plate 105 of the battery pack 100 as viewed from the outside of the battery pack 100 of FIG. 1. FIG. [Figure 2B] 2 is a partial perspective view of a pressure relief device 101 and a top plate 105 of the battery pack 100 as viewed from the inside of the battery pack 100 of FIG. 1. FIG. [Figure 3A] FIG. 2 is a perspective view of the pressure relief device 101 of FIG. [Figure 3B] FIG. 3B is an exploded view of the pressure relief device 101 of FIG. 3A. [Figure 3C] 3B is an axial cross-sectional view of the pressure relief device 101 of FIG. 3A taken along line AA of FIG. 3A. [Figure 3D] 3B is an axial cross-sectional view of the pressure relief device 101 of FIG. 3A taken along a line at a 90 degree angle to the line of sight AA of FIG. 3A. [Figure 3E] FIG. 3D is a cross-sectional view taken along the arrow CC in FIG. 3C. [Figure 4] 2 is a longitudinal cross-sectional view of the pressure relief device 101 of FIG. 1 in a concentrated pressure relief state. [Figure 5] FIG. 2B is a partial perspective view of the top plate of the battery pack 100 of FIG. 2A. [Figure 6A] 6 is a schematic diagram of a step of attaching the pressure relief device 101 of FIG. 1 to the top plate 105 of the battery pack 100 shown in FIG. 5. [Figure 6B] 6 is a schematic diagram of a step of attaching the pressure relief device 101 of FIG. 1 to the top plate 105 of the battery pack 100 shown in FIG. 5. [Figure 7A] 2B is an axial cross-sectional view of the pressure relief device 101 attached to the top plate 105 of the battery pack 100 of FIG. 2A cut at different positions. [Figure 7B] 2B is an axial cross-sectional view of the pressure relief device 101 attached to the top plate 105 of the battery pack 100 of FIG. 2A cut at different positions. DETAILED DESCRIPTION OF THE INVENTION

[0014] Specific embodiments of the present disclosure are described below with reference to the accompanying drawings, which form a part of this specification. While directional terms such as "front," "rear," "up," "down," "left," and "right" are used in this disclosure to describe various exemplary structures and structural elements, it should be understood that these terms used herein are used merely for ease of description and are determined based on the exemplary orientations shown in the accompanying drawings. Because the embodiments disclosed in this disclosure can be positioned in different orientations, these directional terms are merely exemplary and should not be understood as limiting. Where possible, the same or similar reference numerals used in this disclosure refer to the same components.

[0015] FIG. 1 shows a schematic diagram of a battery pack 100 using a pressure relief device 101 according to one embodiment of the present application. As shown in FIG. 1, the battery pack 100 is generally rectangular. In other embodiments, the battery pack 100 may have other shapes. The battery pack 100 includes a battery pack housing 102 and a pressure relief device 101. The battery pack housing 102 has an accommodating space formed therein for accommodating battery cells (not shown). The pressure relief device 101 is attached to a top plate 105 of the battery pack housing 102 and communicates with the accommodating space within the battery pack housing 102, so as to be able to release pressure in the accommodating space within the battery pack housing 102.

[0016] 2A is a partial perspective view of the pressure relief device 101 and the top plate 105 of the battery pack 100 as viewed from the outside of the battery pack 100 of FIG. 1, illustrating the structure of the pressure relief device 101 outside the battery pack housing 102. FIG. 2B is a partial perspective view of the pressure relief device 101 and the top plate of the battery pack 100 as viewed from the inside of the battery pack 100 of FIG. 1, illustrating the structure of the pressure relief device 101 inside the battery pack housing 102. As shown in FIGS. 2A and 2B , the battery pack housing 102 is provided with a mounting hole 230, and the pressure relief device 101 is attached to the battery pack housing 102 through the mounting hole 230. The lower part of the pressure relief device 101 passes through the mounting hole 230 and extends into the battery pack 100, and the upper part of the pressure relief device 101 is exposed to the external environment. When the gas pressure in the battery pack 100 reaches or exceeds a predetermined value, the pressure release device 101 can release the gas in the battery pack 100 intensively to the external environment, thereby releasing the pressure in the battery pack 100.

[0017] Figure 3A is a perspective view of the pressure relief device 101 of Figure 1, and Figure 3B shows an exploded view of the pressure relief device 101 of Figure 3A. Figure 3C is an axial cross-sectional view of the pressure relief device 101 of Figure 3A taken along line AA of Figure 3A. Figure 3D is an axial cross-sectional view of the pressure relief device 101 of Figure 3A taken along a line at a 90-degree angle to line AA of Figure 3A. Figure 3E is a cross-sectional view of the pressure relief device 101 of Figure 3A taken along line CC of Figure 3C. These figures collectively show the specific structure of the pressure relief device 101.

[0018] 3A and 3B, the pressure relief device 101 includes a protective cover 3501, a pressure relief member 3502, a waterproof gas-permeable membrane 3503, a valve core 3504, a mounting base 3505, and a sealing ring 3506. Both the pressure relief member 3502 and the sealing ring 3506 are in the form of circular rings and made of elastic materials. In this embodiment, the pressure relief member 3502 and the sealing ring 3506 are made of silica gel or rubber. For example, the pressure relief member 3502 is made of LR or HNBR material, and the sealing ring 3506 is made of VMQ or EPDM material. The cross sections of the protective cover 3501, the waterproof gas-permeable membrane 3503, the valve core 3504, and the mounting base 3505 are generally circular. The waterproof, gas-permeable membrane 3503 is made from a waterproof, gas-permeable material, and the protective cover 3501, valve core 3504, and mounting base 3505 are made from a material that is heat-resistant and has some rigidity. In this embodiment, the waterproof, gas-permeable membrane 3503 is made from an ePTFE material. The protective cover 3501, valve core 3504, and mounting base 3505 are made from a PA66 material.

[0019] As shown in Figures 3C and 3D, the protective cover 3501 is snapped onto the mounting base 3505 so that the waterproof gas-permeable membrane 3503, the valve core 3504, and the pressure release member 3502 can be accommodated within the space formed by the mounting base 3505 and the protective cover 3501.

[0020] 3C and 3D in combination with FIG. 3B, protective cover 3501 has top cover 330 and cover wall 331. Top cover 330 is in the form of a circular flat plate, and cover wall 331 extends vertically downward from the outer edge of top cover 330. Protective cover 3501 is provided with a plurality of protective cover through-holes 3511 that assist in releasing gas within pressure relief device 101 to the external environment. Top cover 330 is provided with a plurality of ribs 3460 on its inner surface that abut against the top end of mounting base 3505. Cover wall 331 is provided with a plurality of notches 380 and a plurality of snap receivers 332 arranged in notches 380. The inner and outer surfaces of snap receivers 332 are flush with the inner and outer surfaces of cover wall 331, respectively. The snap receiver 332 and the side wall of the corresponding notch 380 in the cover wall 331 are separated by a partition slot 333, which extends from the outer edge of the cover wall 331 toward the top cover 330. The partition slot 333 is provided so that an upper end 334 of the snap receiver 332 is connected to the cover wall 331 and a gap is formed between a lower end 335 of the snap receiver 332 and the cover wall 331, so that when an external force is applied to the lower end 335 of the snap receiver 332, the lower end 335 of the snap receiver 332 can expand and contract relative to the cover wall 331. In other words, when an inward force is applied to the lower end 335 of the snap receiver 332, the lower end 335 of the snap receiver 332 bends toward the space enclosed by the cover wall 331, and when an outward force is applied to the lower end 335 of the snap receiver 332, the lower end 335 of the snap receiver 332 bends outward from the space enclosed by the cover wall 331. The snap receiver 332 has snap holes 336 formed near the lower end 335, which extend through the inner and outer surfaces of the snap receiver 332 and are used to fit over and receive snap members 350 on the mounting base 3505. In this embodiment, six snap receivers 332 are provided on the cover wall 331 of the protective cover 3501. In other embodiments, the number of snap receivers 332 may be different.

[0021] As shown in FIGS. 3B to 3D , the valve core 3504 includes a valve core body 340 and a valve core mounting member 341. The valve core body 340 has a circular cross section and includes a valve core outer rim 342, a valve core central post 344, and a plurality of valve core spokes 343. The valve core outer rim 342 is ring-shaped, and the valve core central post 344 is located at the center of the valve core outer rim 342 and extends along the axis of the valve core 504. One end of each of the valve core spokes 343 is connected to the valve core central post 344, and the other end is connected to the valve core outer rim 342. The valve core spokes 343 can be used to support the waterproof gas-permeable thin film 3503. In this embodiment, the valve core 3504 has eight valve core spokes 343, which are evenly spaced around the valve core central post 344, thereby forming eight valve core through-holes 3514 inside the valve core outer rim 342. The valve core mounting member 341 is formed to extend downward from the valve core central post 344 and is approximately perpendicular to the valve core body 340 .

[0022] 3C and 3D, the valve core mounting member 341 includes an extension 3422 and a pair of arms 3424. The extension 3422 is generally cylindrical, and the proximal end of the extension 3422 is connected to the valve core body 340. The pair of arms 3424 are connected to the distal end of the extension 3422, and the pair of arms 3424 are separated by a recess 3420. Sloped flanges are provided on the outer surfaces of the pair of arms 3424 facing opposite each other, and the flanges extend obliquely outward from the ends of the pair of arms 3424 toward the distal end of the extension 3422. Thus, a stepped snap portion is formed between the outer surfaces of the pair of arms 3424 and the extension 3422. When the pair of arms 3424 are pressed by an external force, the pair of arms 3424 are urged toward each other toward the recess 3420 until the inner sides of the pair of arms 3424 abut against each other. When the external force is removed, the pair of arms 3424 move away from each other and return to their extended positions relative to each other. The above-described configuration of the valve core mounting member 341 makes the valve core mounting member 341 expandable and contractible, allowing the valve core 3504 to be removably mounted to the mounting base 3505.

[0023] As shown in FIGS. 3B to 3D , the waterproof, gas-permeable thin film 3503 is a thin, circular sheet, approximately the same size as the cross section of the valve core body 340, allowing the waterproof, gas-permeable thin film 3503 to fit snugly over the top surface of the valve core body 340. The waterproof, gas-permeable thin film 3503 prevents liquid penetration while allowing gas to pass through, thereby achieving dustproof, waterproof, and gas-permeable effects. In this embodiment, the waterproof, gas-permeable thin film 3503 meets the IP67 requirements. Furthermore, in this embodiment, the waterproof, gas-permeable thin film 3503 is fixed to the top surface of the valve core 3504 by ultrasonic welding, and in this case, the valve core spokes 343 are also welded. In other embodiments, the waterproof, gas-permeable thin film 3503 can be connected to the valve core 3504 by other connection means, such as bonding with an adhesive or fixing by a post-molding process.

[0024] The pressure release member 3502 is in the form of a ring. The pressure release member 3502 has an outwardly flaring axial section with an inner edge 3551 that forms the inner periphery of the pressure release member 3502, and an outer edge 3553 that extends downwardly and outwardly from the inner edge 3551. In its free state, i.e., without interference from an external force, the outer edge 3553 of the pressure release member 3502 extends outwardly from the inner edge 3551 and is located below the inner edge 3551. In this embodiment, the pressure release member 3502 has an inner diameter approximately equal to the outer diameter of the valve core body 340 and is fixedly connected to the valve core 3504 by molding, such that the inner periphery of the pressure release member 3502 and the outer periphery of the valve core 3504 are closely attached to one another. In other embodiments, other fastening means can be used. For example, the inner diameter of the pressure release member 3502 is slightly smaller than the outer diameter of the valve core body 340, such that the pressure release member 3502, by virtue of its expandable and contractible nature, is able to securely fit over the outer edge of the valve core 3504. As shown in Figures 3C and 3D, once the pressure release member 3502 is fitted over the valve core 3504, the pressure release member 3502 and valve core 3504 generally form an overall umbrella-like shape.

[0025] 3B-3D, the mounting base 3505 has a main body portion 301. The main body portion 301 is in the form of a cylindrical sleeve having a circular cross section. As shown in FIG. 4A, the main body portion 301 is divided into a head portion 3431 and an insert portion 3432. The head portion 3431 is connected to an upper end 3438 of the insert portion 3432 at a connecting end 3435 of the head portion. The insert portion 3432 is configured to be inserted into the mounting hole 230, and the head portion 3431 is located outside the mounting hole 230 and is connected to the protective cover 3501.

[0026] The snap members 350 are provided on the outer surface of the head 3431. The snap members 350 are formed to protrude outward from the outer surface of the head 3431. The snap members 350 are snapped into and fitted with the snap receivers 332 on the protective cover 3501. The number of snap members is the same as the number of snap receivers 332. In this embodiment, since six snap receivers 332 are provided on the protective cover 3501, the mounting base 3505 also has six snap members 350 on the outer surface of the head 3431. As can be seen from FIGS. 3B and 3D , the snap members 350 are generally prism-shaped, and their lower surfaces 3452 are flat surfaces perpendicular to the outer surface of the head 3431, and their upper surfaces 3451 are inclined surfaces extending at an angle downward from the outer surface of the head 3431. 3D , when the protective cover 3501 is snapped onto the mounting base 3505, the protective cover 3501 is fixed to the outside of the head 3431 from above the mounting base 3505, and the inner surface of the protective cover 3501 is closely attached to the outer surface of the head 3431 at the cover wall 331, thereby ensuring a fixed connection between the protective cover 3501 and the mounting base 3505 in the horizontal direction. When the protective cover 3501 is snapped onto the mounting base 3505 from above to below, the snap receivers 332 can expand outward, and the six snap members 350 are accommodated in the snap holes 336 of the six snap receivers 332, respectively. In this case, the lower surfaces 3452 of the snap members 350 abut against the snap holes 336, and the snap members 350 are configured to fit into the snap holes 336 so as to prevent the protective cover 3501 from moving upward relative to the mounting base 3505. Furthermore, as shown in FIG. 3D , when protective cover 3501 is snapped onto the top end of mounting base 3505, ribs 3460 on the inner surface of top cover 330 of protective cover 3501 precisely abut against the top end of mounting base 505, thereby preventing protective cover 501 from moving downward relative to mounting base 505.

[0027] As shown in FIGS. 3B, 3C, and 3D, the head 3431 of the mounting base 3505 has a larger outer diameter than the insert portion 3432. The body portion 301 of the mounting base 3505 has a fluid passageway 3401 therein that passes through the head 3431 and the insert portion 3432. The portion of the fluid passageway 3401 in the head 3431 has a larger inner diameter than the portion of the fluid passageway 3401 in the insert portion 3432, and thus the mounting base 3505 forms an annular support platform 3459 where the head 3431 and the insert portion 3432 join. A support structure 3512 is provided within the fluid passageway 3401, and is located within the insert portion 3432 and extends inward from the support platform 3459. As shown in FIG. 3B, the support structure 3512 includes a central support post 337 and a plurality of support plates 338. The central support post 337 is located at the center of the fluid passage 3401. One end of each support plate 338 is fixed to the central support post 337, and the other end is fixed to the inner wall of the main body portion 301, so that multiple support plates 338 are radially arranged within the fluid passage 3401. In this embodiment, there are a total of six support plates 338, which divide the fluid passage 3401 into six sub-passages 339, each of which has a vertically connected structure. The support structure 3512 has a relatively large height at the position where the central support post 337 is located, so that the central support post 337 can be used to engage with and support the valve core 3504. As shown in FIG. 3C , the central support post 337 is provided with a mounting member through-hole 3510. The inner diameter of the mounting member through-hole 3510 is approximately equal to the outer diameter of the extension 3422 of the valve core mounting member 341, so that the extension 3422 of the valve core 340 can be snugly received in the mounting member through-hole 3510 of the mounting base 3505. When the valve core 3504 is engaged onto the central support post 337 by the pair of arms 3424 of the valve core mounting member 341, the lower surface of the central portion of the valve core body 340 is precisely attached to the upper surface of the central support post 337, limiting the upward and downward movement of the valve core 3504 relative to the mounting base 3505.

[0028] The mounting base 3505 further includes a restraining portion 302 and a pair of lugs 303. The restraining portion 302 and the pair of lugs 303 cooperate to hold the mounting base 3505 in the mounting hole 230 in the top panel 105 of the battery pack 100. The restraining portion 302 is disposed at an upper end of the insertion portion 3432 and protrudes outward from the body portion 301. In the illustrated embodiment, the restraining portion 302 is disposed at a connecting end 3435 of the head portion 3431 and is formed to have a flange shape around the connecting end 3435 of the head portion 3431. In some embodiments, if the size of the restraining portion 302 is configured such that the restraining portion 302 cannot be inserted into the mounting hole 230, the restraining portion 302 may extend directly from the upper end 3438 of the insertion portion 3432.

[0029] The pair of lugs 303 are disposed on the outer circumferential surface of the insertion portion 3432, and therefore the lugs 303 are positioned below the restraining portion 302. The lugs 303 are separated by a certain distance from the restraining portion 302 so as to form a clamping space 3900. The height of the clamping space 3900 is equal to the thickness of the top plate 105 of the battery pack housing 102 or slightly greater than the thickness of the battery pack housing 102 so that the battery pack housing 102 can be accurately clamped between the restraining portion 302 and the insertion portion 3432.

[0030] 3D, the lower surface of the restraining portion 302 is flush with the lower edge of the head portion 3431, and is provided with a seal ring groove 3455 for accommodating a seal ring 3506. As can be seen from FIG. 3C in combination with FIG. 3A, the inner side of the seal ring groove 3455 is formed as a circular ring-shaped platform 3456, and the outer side is formed with a plurality of outer abutment elements 3457, which are spaced apart along the outer edge of the restraining portion 302. As shown in FIG. 3A, some of the outer abutment elements 3457 are independently arranged on the lower surface of the restraining portion 302, while the remaining outer abutment elements 3457 have ends close to the outer edge of the restraining portion 302 connected together by connecting bars 3458, while the ends facing the main body portion 301 are still arranged separately. 3A shows five outer abutment elements 3457, two of which located on two radial sides of the restraining part 302 are independently arranged, and the outer ends of the remaining three outer abutment elements 3457, which are arranged between the two outer abutment elements 3457 mentioned above, are connected together by a connecting bar 3458. The circular ring-shaped platform 3456 and the plurality of outer abutment elements 3457 are configured to mate with each other so that a seal ring groove 3455 is formed on the underside of the restraining part 302 that engages with the seal ring 3506.

[0031] 3A, 3B, and 3C, a pair of lugs 303 of the mounting base 3505 protrude outward from the outer surface of the insertion portion 3432 and are arranged symmetrically with respect to the axis of the insertion portion 3432. As shown in FIGS. 3C and 3E, each of the lugs 303 includes a resilient arm 3701 and a housing portion 3702. A proximal end 3711 of the resilient arm 3701 is connected to the insertion portion 3432, and a distal end 3712 of the resilient arm 3701 is a free end having a protrusion 3704 on its upper surface that extends or protrudes toward the restraining portion 302. The housing portion 3702 is connected to the insertion portion 3432, and a housing space 3703 is defined within the housing portion 3702. The accommodation portion 3702 is U-shaped, and the open end of the U is connected to the outer surface of the insertion portion 3432, so that the accommodation portion 3702 and the insertion portion 3432 together form an accommodation space 3703. As shown in FIG. 3C , in a free state, most of the elastic arm 3701 is accommodated within the accommodation space 3703 of the accommodation portion 3702. The upper surface of the elastic arm 3701 is generally flush with the upper surface of the accommodation portion 3702, but the protrusion 3704 of the distal end 3712 of the elastic arm 3701 is higher than the upper surface of the accommodation portion 3702. When a downward force is applied to the free end 3712 of the elastic arm 3701, the distal end 3712 of the elastic arm 3701 can move downward, and the entire elastic arm 3701 is accommodated within the accommodation space 3703 of the accommodation portion 3702.

[0032] 3B and 3C, the mounting base 3505 also has a head 3431 provided with a plurality of openings 3403, which are disposed on the upper edge of the restraining portion 302 and pass through the head 3431 so that gas in the fluid passage 3401 can be released to the external environment through the openings 3403. The openings 3403 are elongated, and the length direction of the openings 3403 corresponds to the circumferential direction of the head 3431, and the plurality of openings 3403 are disposed at intervals around the circumferential direction of the head 3431. In this embodiment, the head 3431 is provided with six openings 3403, but the number of openings 3403 may be different in other embodiments.

[0033] The seal ring 3506 has a circular ring shape and is received in the seal ring groove 3455 of the mounting base 3505. As shown in FIGS. 3A and 3D , when the seal ring 3506 is engaged in the seal ring groove 3455, the inner side of the seal ring 3506 fits against the outer surface of the circular ring-shaped platform 3456, and the outer side of the seal ring 3506 abuts against the inner edge of the outer abutment element 3457. In this embodiment, the seal ring 3506 and the seal ring groove 3455 are engaged together by an interference fit. Because there are spaces between the multiple, separately arranged outer abutment elements 3457, the interference-fitted seal ring 3506 is extruded excessively, thereby ensuring not only a fixed engagement between the seal ring 3506 and the seal ring groove 3455 but also a tight engagement between the seal ring 3506 and the seal ring groove 3455. In another embodiment, the seal ring 3506 can be fixed to the underside of the mounting base 3505 by secondary molding.

[0034] To assemble the pressure release device 101, first, the pressure release member 3502 can be fixedly connected to the valve core 3504 by secondary molding, and the waterproof gas-permeable thin film 3503 is fixed to the upper surface of the valve core 3504 by ultrasonic welding, then the valve core 3504 with the pressure release member 3502 and the waterproof gas-permeable thin film 3503 fixed thereon is engaged onto the support structure 3512 of the mounting base 3505, and finally, the protective cover 3501 is fixed onto the mounting base 3505 by a snap connection. As shown in Figures 3C and 3D, the support structure 3512 has a relatively large height at the location of the central support post 337, so that when the valve core 3504 with the pressure release member 3502 disposed thereon is aligned with the fluid passage 3401 and engages on the support structure 3512 of the mounting base 3505, the central portion of the valve core body 340 abuts against the support structure 3512 and the edge of the valve core body 340 is suspended above the support structure 3512, thus forming a pressure release passage 3402 between the outer edge of the valve core 3504 and the inner wall of the fluid passage 3401 of the mounting base 3505 (shown in Figure 4).

[0035] FIG. 4 is a longitudinal cross-sectional view of the pressure relief device 101 of FIG. 1 in a concentrated pressure relief state, illustrating the deformation of the pressure relief member 3502 in the concentrated pressure relief state.

[0036] In use, the bottom of the pressure release device 101 faces the component that receives the pressure release. In this embodiment, the component that receives the pressure release is the battery pack 100. The mounting base 3505 has a fluid passage 3401 therein, so that the underside of the pressure release member 3502 in the pressure release device 101 communicates with the interior of the battery pack 100. The underside of the internal pressure release member 3502 is the pressure-receiving side. As shown in FIG. 3C , in its free state, the pressure release member 3502 extends diagonally downward, and the outer edge of the pressure release member 3502 abuts against the support platform 3459 inside the mounting base 3505, thereby closing the pressure release passage 3402 and placing the pressure release member 3502 in a closed operating state. The pressure release member 3502 is made of an elastic material and can be deformed by the action of an external force. However, when the pressure inside the battery pack 100 is below a predetermined value, the pressure received by the pressure release member 3502 is small and the degree of deformation is small, which is not enough to open the pressure release passage 3402. In this case, since the protective cover 3501 and the valve core 3504 are both provided with through-holes, the gas inside the battery pack 100 can be slowly released to the external environment through the waterproof gas-permeable thin film 3503.

[0037] As shown in FIG. 4 , when the gas pressure inside the battery pack 100 exceeds a predetermined value, i.e., when the gas pressure below the pressure release member 3502 becomes relatively large, the pressure release member 3502 deforms, causing the outer edge of the pressure release member 3502 to bend upward, thereby opening the pressure release passage 3402 and placing the pressure release member 3502 in an open state. The opening 3403 in the head 3431 is located immediately outside the pressure release passage 3402 and above the support platform 3459, so that gas leaking from the pressure release passage 3402 can be quickly released directly to the external environment through the opening 3403. When the pressure release member 3502 deforms and opens to release pressure, the waterproof gas-permeable membrane 3503 can also function as a permeable membrane. However, the permeability of the waterproof gas-permeable membrane 3503 is much lower than the permeability caused by the opening of the pressure release member 3502. When a sufficient time has passed for pressure release and the gas pressure inside the battery pack 100 falls below a predetermined value, the pressure release member 3502 returns to the initial state shown in FIG. 3C , the pressure release passage 3402 is closed, and gas is released from the battery pack 100 only through the waterproof, gas-permeable membrane 3503. That is, when the pressure inside the battery pack 100 does not reach a predetermined value, the gas permeability of the battery pack 100 is achieved by the waterproof, gas-permeable membrane 3503. On the other hand, when the pressure inside the battery pack 100 exceeds the predetermined value, the battery pack 100 quickly releases pressure through the pressure release member 3502. In this case, the waterproof, gas-permeable membrane 3503 also provides permeability, but the pressure release speed through the waterproof, gas-permeable membrane 3503 is slow.

[0038] The present application employs a structure in which the valve core 3504 and the mounting base 3505 cooperate with each other to define the pressure release passage 3402 in the pressure release device 101. The elasticity of the pressure release member 3504 is used to open and close the pressure release passage 3402, thereby releasing the pressure within the battery pack 100. The unique structure of the pressure release device 101 prevents damage each time the pressure release member 3504 opens to release pressure. Therefore, the pressure release device 101 of the present application can be reused without replacing it with a new one after pressure release, thereby significantly reducing the usage cost of the pressure release device 101. Furthermore, the predetermined pressure value at which the pressure release device 101 of the present application can release pressure can be adjusted based on the selection of the material of the pressure release member 3502. If the pressure release member 3502 has a relatively high elasticity and a relatively low hardness, the predetermined pressure value of the pressure release device 101 will be relatively low. Furthermore, if the pressure release member 3502 has a relatively low elasticity and a relatively high hardness, the predetermined pressure value of the pressure release device 101 will be relatively high. In the present application, LR or HNBR material is used to prepare the pressure release member 3502. When the pressure inside the battery pack 100 is relatively low, the pressure release device 101 of the present application can perform pressure release, thereby effectively ensuring the installation and use of the battery pack 100.

[0039] FIG. 5 shows a partial perspective view of the top plate 105 of the battery pack 100 of FIG. 2A , illustrating the specific structure of the mounting hole 230 in the top plate 105. As shown in FIG. 5 , a pair of notches 5313 and a pair of slots 5314 are provided in the wall of the mounting hole 230. The mounting hole 230 is generally circular, and the diameter of the mounting hole 230 is equal to or slightly larger than the cross-sectional diameter of the insertion portion 3432. The number of notches 5313 is the same as the number of lugs 303 in the pressure relief device 101, and the number of slots 5314 is the same as the number of elastic arms 3701 in the pressure relief device 101. Corresponding to the pair of lugs 303 and the pair of elastic arms 3701 in the pressure relief device 101 of this embodiment, a pair of notches 5313 and a pair of slots 5314 are provided corresponding to the mounting hole 230. The pair of notches 5313 and the pair of slots 5314 are each symmetrically positioned about the center of the mounting hole 230, with the pair of slots 5314 and the pair of notches 5313 being staggered. In the illustrated embodiment, the pair of notches 5313 and the pair of slots 5314 are spaced apart at four quadrant locations in the wall of the mounting hole 230. The notches 5313 are sized to receive the lugs 303 of the mounting base 505, and the slots 5314 are sized to receive the resilient arms 701 of the lugs 303.

[0040] 6A and 6B are schematic diagrams of the steps of attaching the pressure relief device 101 of FIG. 3A to the top plate 105 of the battery pack 100 shown in FIG. 5. For ease of illustration, FIGS. 6A and 6B show the attachment and mating relationship between the pressure relief device 101 and the battery pack housing 102 in a cross-sectional view of the pressure relief device 101 taken along line CC of FIG. 3C.

[0041] As shown in FIG. 6A , when attaching the pressure relief device 101 to the top plate 105 of the battery pack housing 102 from outside the battery pack 100, the pair of lugs 303 of the pressure relief device 101 are aligned with the pair of notches 5313 in the mounting hole 230 of the top plate 105, respectively, and then the insertion portion 3432 of the pressure relief device 101 is inserted into the mounting hole 230. The pressure relief device 101 is further inserted until the pair of lugs 303 move to a position below the top plate 105 of the battery pack housing 102. Because the cross-sectional area of ​​the restraining portion 302 is larger than the cross-sectional area of ​​the mounting hole 230, the restraining portion 302 abuts against the top plate 105. Then, the pressure relief device 101 is rotated 90 degrees relative to the top plate 105. During the rotation, the two elastic arms 3701 on the lugs 303 always abut against the underside of the battery pack housing 102. After rotating 90 degrees, the pair of resilient arms 701 reach the positions of the pair of slots 5314, respectively, and the distal ends 3712 of the pair of resilient arms 3701 spring upward to be partially received in the corresponding slots 5314, thereby attaching the pressure relief device 101 to a proper position in the mounting hole 230. Due to the engagement and matching relationship between the resilient arms 3701 and the slots 5314, the pressure relief device 101 and the mounting hole 230 do not easily move relative to each other, thereby positioning the pressure relief device 101 and preventing the pressure relief device 101 from rotating relative to and disengaging from the battery pack housing 102 during the process of attaching the pressure relief device 101 in the battery pack housing 102. When the lug 303 is rotated and disengaged from the notch 5313 position, the rotated lug 303 abuts against the underside of the battery pack housing 102 and cooperates with the stop portion 302 on the top surface of the battery pack housing 102 to clamp the top plate 105 of the battery pack housing 102 within the clamp space 3900, thereby fixing the pressure relief device 101 on the battery pack housing 102 and restricting the vertical movement of the pressure relief device 101 relative to the battery pack housing 102.

[0042] 7A and 7B are axial cross-sectional views of the pressure relief device 101 attached to the top plate 105 of the battery pack 100 of FIG. 2A taken at different positions, illustrating the fitting relationship between the sealing ring 3506 and the top plate 105 of the battery pack 100. As shown in FIGS. 7A and 7B, the pressure relief device 101 is attached to a position within the mounting hole 230 in the battery pack housing 102, with the head 3431 generally located above the battery pack housing 102 and the insertion portion 3432 generally located below the battery pack housing 102. The restraining portion 302 and the lug 303 abut against the upper and lower surfaces of the battery pack housing 102, respectively. When the sealing ring 3506 is attached to the underside of the restraining portion 302 by an interference fit and the sealing ring 506 abuts against the upper surface of the battery pack housing 102, the top plate 105 of the battery pack housing 102 is prevented from loosening between the restraining portion 302 and the lug 303 of the pressure relief device 101, and the fastening effect of the restraining portion 302 and the lug 303 to the top plate 105 of the battery pack housing 102 is promoted. Furthermore, the arrangement of the sealing ring 3506 also helps to seal the pressure relief device 101 from the battery pack housing 102, effectively preventing external dust particles or liquid from entering the battery pack 100 through the gap between the pressure relief device 101 and the battery pack housing 102.

[0043] In the present application, the restraining portion 302 is disposed at the upper end of the insertion portion 3432 of the mounting base 3505 of the pressure relief device 101, the lugs 303 are disposed at the insertion portion 3432, and notches 5313 capable of receiving the lugs 303 are disposed in the walls of the mounting holes 230 in the battery pack housing 102, and due to the matching relationship between the restraining portion 302, the lugs 303, and the mounting holes 230, only two steps are required to securely attach the pressure relief device 101 to the battery pack 100 by means of the restraining portion 302 and the lugs 303: inserting the insertion portion 3432 into the mounting holes 230 and rotating the insertion portion 3432, without requiring any additional mounting parts or tools, thereby significantly simplifying the assembly steps of the pressure relief device 101. In this embodiment, the lugs 303 of the pressure relief device 101 include two lugs 303, but in other embodiments, other numbers of lugs 303, such as one, three, or four, can be used. Furthermore, it is also necessary to provide a corresponding number of snap receiving portions 313 in the mounting holes 300 in the battery pack housing 102 to match the arrangement of the number of lugs 303. [Industrial Applicability]

[0044] The pressure relief device 101 of the present application is used in a battery pack 100. In other embodiments, the pressure relief device 101 can be provided in other components that require pressure relief. In this embodiment, the battery pack 100 employing the pressure relief device 101 is installed in an electric vehicle, such as an electric car, a hybrid vehicle, etc. In other embodiments, the pressure relief device 101 can also be used in battery packs 100 in other technical fields. [Explanation of symbols]

[0045] 100 battery packs 101 Pressure relief device 102 Battery pack housing 105 Top Plate 230 holes 300 holes 301 Main body part 302 Stopping part 303 Rug 313 parts 330 Top cover 331 Cover Wall 333 Slots 334 Upper end 335 Lower end 336 Snap Hole 337 Central Support Post 338 Support plate 339 Sub-passage 340 Valve core body 341 Components 342 Valve core outer rim 343 Valve Core Spokes 344 Valve core center post 350 Snap member 380 notch 501 Protective Cover 504 valve core 505 Mounting base 506 Seal Ring 701 Elastic Arm 3401 Fluid passage 3402 Pressure relief passage 3403 Aperture 3420 recess 3422 Extension 3424 Arm 3431 Head 3432 Insertion part 3435 Connection end 3438 Upper end 3451 Top surface 3452 Bottom side 3455 Seal ring groove 3456 Platform 3457 Outer abutment element 3458 Connection Bar 3459 Support Platform 3460 Rib 3501 Protective Cover 3502 Pressure release member 3503 Waterproof and gas-permeable thin film 3504 valve core 3505 Mounting base 3506 Seal ring 3510 Component through hole 3511 Protective cover through hole 3512 Support Structure 3514 Valve core through hole 3551 Inner edge 3553 outer edge 3701 Elastic Arm 3702 Storage area 3703 Containment Space 3704 Protrusion 3711 Proximal end 3712 Distal end 3900 Clamp space 5313 Notch 5314 Slots

Claims

1. In the pressure relief device, a mounting base (3505) having a fluid passage (3401) therein, the fluid passage (3401) being capable of communicating with an internal space of a component that is subjected to pressure relief; a valve core (3504) positioned in alignment with the fluid passage (3401) in the mounting base (3505), wherein a pressure release passage (3402) is formed between an outer edge of the valve core (3504) and an inner wall of the fluid passage (3401) in the mounting base (3505); a pressure release member (3502) fitted over the outer edge of the valve core (3504), the pressure release member (3502) being deformable and opening and closing the pressure release passage (3402) by the deformation; The valve core (3504) comprises a ring-shaped valve core outer rim (342), a valve core central post (344) positioned at the center of the valve core outer rim (342) and extending along the axis of the valve core, a plurality of valve core spokes (343) connected at one end to the valve core central post (344) and at the other end to the valve core outer rim (342), and a gas-permeable membrane (3503) fixed to the upper surfaces of the valve core outer rim (342) and the valve core spokes (343).

2. the pressure relief member (3502) has a pressure-receiving side, and the pressure relief member (3502) may be configured to have a closed operational state in which the pressure relief passage (3402) is closed, and an open operational state; When the pressure on the pressure-receiving side of the pressure release member (3502) exceeds a predetermined value, the pressure release member (3502) deforms, causing the pressure release member (3502) to change from the closed operational state to the open operational state in which the pressure release passage (3402) is open; 10. The pressure relief device of claim 1, wherein the pressure relief member (3502) returns to the closed operating state when the pressure on the pressure receiving side of the pressure relief member (3502) falls below the predetermined value.

3. 10. The pressure relief device of claim 1, wherein the pressure relief member (3502) is made of a material having deformation properties.

4. The valve core (3504) has a circular cross section; 2. The pressure relief device of claim 1, wherein the pressure relief member (3502) is in the form of a ring, the pressure relief member (3502) having an inner edge (3551) and an outer edge (3553), the inner edge (3551) being connected to the valve core (3504), and the outer edge (3553) abutting the mounting base (3505) in a free state to close the pressure relief passage (3402).

5. 5. A pressure relief device as set forth in claim 4, wherein said pressure relief member (3502) extends outwardly and downwardly from said inner edge (3551) to said outer edge (3553).

6. 10. The pressure relief device of claim 1, wherein the valve core (3504) is made of plastic, and the pressure relief member (3502) is secured to an outer surface of the valve core (3504) by a molding process.

7. The valve core (3504) is provided with a valve core through hole (3514), The pressure relief device (101) of claim 1 further comprises a waterproof gas-permeable membrane (3503) that covers the valve core through hole (3514) of the valve core (3504) so ​​that gas from the pressure relief passage (3401) can be released to the external environment through the waterproof gas-permeable membrane (3503).

8. The pressure relief device (101) further comprises a protective cover (3501), the protective cover (3501) having a protective cover through-hole (3511), the protective cover (3501) being snapped onto the mounting base (3505), and the valve core (3504) and the pressure relief member (3502) being accommodated within the space formed by the mounting base (3505) and the protective cover (3501).

9. The pressure relief device of claim 1, wherein the mounting base (3505) has at least one opening (3403) located close to the pressure relief member (3502), and when the outer edge of the pressure relief member (3502) bends upward, gas flowing between the outer edge of the pressure relief member (3502) and the inner wall of the fluid passage (3401) can be released to the external environment through the at least one opening (3403).

10. The pressure relief device (101) is used in a battery pack (100), the battery pack (100) includes a battery pack housing (102), the battery pack housing (102) is provided with a mounting hole (230), and the pressure relief device (101) is attached to the battery pack housing (102) through the mounting hole (230), as described in any one of claims 1 to 9.

Images