A single cell and a battery pack

Abstract

The application discloses a single battery and a battery pack, comprising a shell, an electric core and a pressure relief unit, the shell is provided with a connecting part with a first through hole and a first chamber for accommodating the electric core, the first chamber is communicated with the first through hole, the pressure relief unit comprises a switching valve and an air bag connected with each other, the air bag forms a second chamber inside, the switching valve is movably assembled in the connecting part and has a first station and a second station; when the switching valve is switched to the first station, the first chamber and the second chamber are communicated; when the switching valve is switched to the second station, the first chamber and the second chamber are separated from each other. The application can continuously guide the gas generated in the whole life cycle of the electric core and the by-product gas in the repair process into the air bag through the flow channel, avoid the internal pressure accumulation, ensure the size stability of the single battery, and quickly separate the first chamber and the second chamber through the station switching when the air bag needs to be replaced, cut off the interaction between the electric core and the air bag, and significantly improve the convenience and reliability when the air bag is replaced.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a single cell and a battery pack. Background Technology

[0002] In the field of power batteries, ensuring battery safety and reliability is of paramount importance. Under conditions of abuse such as overcharging and over-discharging, a large amount of gas will be generated inside the battery in a short period of time, causing a sharp rise in gas pressure, which may lead to battery fire and explosion in severe cases.

[0003] To address this issue, the industry standard practice is to weld explosion-proof valves onto the battery top cover or casing, or to install an integrated explosion-proof valve structure. This allows the valve to burst and release pressure when the battery reaches a certain internal pressure, preventing thermal runaway. However, this technology has several drawbacks: 1. Gas production throughout the battery's lifespan increases internal pressure. Before this pressure falls below the explosion-proof valve's burst value, it continues to act on the casing and the valve, affecting battery dimensional stability and the long-term reliability of the valve; 2. Based on the current industry-leading "one-shot" self-healing technology, the small amount of byproduct gas generated during lithium salt decomposition during battery repair cannot be effectively discharged, impacting battery safety and reliability. Summary of the Invention

[0004] This application aims to provide a single-cell battery that at least solves the problem of internal pressure accumulation in the battery.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application propose a single-cell battery, comprising: The outer casing includes a connecting portion having a first through hole, and the outer casing has a first chamber communicating with the first through hole; The battery cell is located within the first chamber; The pressure relief unit includes a transfer valve and an airbag. The transfer valve is movably connected to the connecting part, and the airbag is connected to the end of the transfer valve opposite to the connecting part. The airbag has a second chamber. The transfer valve is movable relative to the connecting part, thereby giving the transfer valve a first position and a second position. Specifically, when the transfer valve is switched to the first working position, the transfer valve connects the first chamber and the second chamber; when the transfer valve is switched to the second working position, the transfer valve isolates the first chamber and the second chamber.

[0006] A single-cell battery according to an embodiment of this application has at least the following beneficial effects: By providing a connecting part with a first through hole on the outer casing, coupled with a transfer valve movable relative to the connecting part and an airbag with a second chamber, the gas path on / off control is achieved by relying on the switchable first and second positions of the transfer valve. When the transfer valve is in the first position, the gas generated during the normal life cycle of the battery cell and the by-product gas generated by lithium salt decomposition during the "one-shot" self-repair technology can be diverted to the airbag. The airbag expands under pressure to reduce the internal pressure of the first chamber, effectively preventing the internal gas pressure of the battery from continuously accumulating below the explosion threshold of the explosion-proof valve, thus eliminating... In addition to the long-term internal pressure exerting force on the battery casing and explosion-proof valve, ensuring the overall dimensional stability of the battery, it also improves the long-term reliability of the explosion-proof valve. When it is necessary to disassemble and replace the airbag or carry out related maintenance work, simply switch the adapter valve to the second position to separate the first and second chambers. The airbag can be operated without damaging the original sealing structure of the battery, preventing external impurities and moisture from entering the cell or electrolyte leakage. While solving the problem of internal pressure accumulation, it also takes into account the convenience of later maintenance of the pressure relief unit. The overall structure is simple and practical, effectively improving the safety and stability of the single battery during use.

[0007] Optionally, the transfer valve includes a main body and a valve plate, the valve plate being fixedly connected within the main body and having a second through hole. The main body is movably connected to the connecting part, and the main body has a flow guiding channel with a sealing element inside. When the transfer valve is switched to the first position, the flow guiding channel connects the first through hole and the second through hole with the sealing element being avoided. When the transfer valve is switched to the second position, the sealing element blocks the first through hole, the second through hole, or the flow guiding channel.

[0008] Optionally, when the main body and the connecting part are movably connected, they can perform any one of the following relative movements: linear movement along the axial direction of the first through hole, rotational movement along the circumferential direction of the first through hole, or helical movement along the axial direction of the first through hole.

[0009] Optionally, the seal is connected to the transfer valve. When the transfer valve is switched to the first position, there is a first flow guide gap between the seal and the first through hole, and the first flow guide gap connects the first through hole and the flow guide channel. When the transfer valve is switched to the second position, the seal blocks the first through hole.

[0010] Optionally, the valve plate portion has a first surface facing the first through hole, the first surface having a central region and a peripheral region located outside the central region, the central region being connected to the seal, and the peripheral region having a plurality of second through holes.

[0011] Optionally, the seal is connected to the connection portion. When the transfer valve is switched to the first position, there is a second flow guide gap between the seal and the second through hole, and the second flow guide gap connects the second through hole and the flow guide channel. When the transfer valve is switched to the second position, the seal blocks the second through hole.

[0012] Optionally, the airbag is detachably connected to the transfer valve.

[0013] Optionally, the housing further includes a top cover having an outer plate surface facing away from the battery cell, wherein the connecting portion protrudes outward relative to the outer plate surface or is recessed inward relative to the outer plate surface.

[0014] Optionally, the single battery cell further includes a detection unit for detecting the size of the airbag, the detection unit including a pressure sensor disposed in the second chamber and / or the first chamber.

[0015] Secondly, embodiments of this application propose a battery pack, which includes the aforementioned individual battery cells.

[0016] A battery pack according to an embodiment of this application has at least the following beneficial effects: the contents of the above-described single-cell battery embodiments are all applicable to the embodiments of this battery pack, the specific functions implemented by the embodiments of this battery pack are the same as those of the above-described single-cell battery embodiments, and the beneficial effects achieved are also the same as those achieved by the above-described single-cell battery embodiments.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is an exploded perspective view of a single battery cell according to an embodiment of the present invention; Figure 2 This is an exploded perspective view of a pressure relief unit according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of the pressure relief unit according to an embodiment of the present invention during the initial stage of pressure relief; Figure 4 This is a cross-sectional view of the pressure relief unit according to an embodiment of the present invention during the later stage of pressure relief; Figure 5 This is a cross-sectional view of the depressurization unit according to an embodiment of the present invention during airbag replacement; Figure 6This is a three-dimensional structural diagram of the transfer valve according to an embodiment of the present invention.

[0019] In the attached diagram: 600-outer shell, 700-battery cell, 200-pressure relief unit, 500-seal, 100-connection, 621-outer plate, 110-first through hole, 630-first chamber, 120-annular mounting groove, 121-elastic sealing ring, 330-inner ring platform, 300-transfer valve, 400-airbag, 310-main body, 320-valve plate, 321-second through hole, 301-flow guide channel, 340-sleeve platform, 410-second chamber, 322-first surface, 130-second surface, 610-shell, 620-top cover, 640-pole post, 302-first flow guide gap. Detailed Implementation

[0020] Embodiments of the present invention will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0021] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] This invention provides a single-cell battery that continuously collects gas generated inside the cell 700 via an airbag 400 throughout the battery's entire lifespan. This prevents the continuous accumulation of internal gas pressure, which could lead to bulging of the casing 600, structural deformation, sealing failure, or even thermal runaway. Furthermore, the airbag 400 can be disassembled and replaced without damaging the internal sealed environment of the battery, or causing electrolyte leakage or the entry of external air into the battery. This significantly improves the battery's safety, structural stability, and lifespan. The following provides a detailed and complete description of the single-cell battery of this application, with reference to its specific structure.

[0025] like Figure 1 and Figure 2 As shown, the single battery includes a casing 600, a cell 700, a pressure relief unit 200, and a sealing element 500. The casing 600 includes a connecting part 100, which serves as a docking structure between the pressure relief unit 200 and the casing 600. The connecting part 100 is integrally configured on the top cover 620 of the casing 600. The connecting part 100 can be integrally formed with the top cover 620. The connecting part 100 can be formed directly on the top cover 620 by stamping, forging, or machining, or it can be an independently processed structural component that is firmly installed in a preset position on the top cover 620 by laser welding, resistance welding, structural adhesive bonding, thread locking, or snap-fit ​​fixing.

[0026] The connecting part 100 has a first through hole 110 extending through its body. The first through hole 110 extends along the inner and outer directions of the single cell, with one end directly communicating with the first chamber 630 of the outer casing 600 for accommodating the cell 700, and the other end opening towards the outside of the outer casing 600, providing a technical basis for the outward discharge of gas generated inside the cell 700. The aperture size of the first through hole 110 can be adaptively designed according to the conventional gas production rate and gas production pressure of different types of cells 700. This ensures that the trace amounts of gas generated by the cell 700 during normal use and self-repair process can pass through quickly and smoothly, while also preventing the structural strength of the connecting part 100 from being reduced due to an excessively large aperture, thus avoiding problems such as deformation and cracking of the connecting part 100 under the action of gas pressure inside the cell 700.

[0027] Furthermore, the structure of the connecting part 100 can be adapted to meet the overall layout requirements of the battery cell 700. In one embodiment, the connecting part 100 protrudes outward from the outer plate surface 621 of the battery cell 700 relative to the top cover 620, thereby forming a boss structure. The first through hole 110 passes through the center of the outer surface of the boss. The transfer valve 300 of the pressure relief unit 200 is movably connected to the outer wall of the boss. The boss structure can provide a clear docking reference for the transfer valve 300, which facilitates the quick positioning and installation of the transfer valve 300.

[0028] In this embodiment, the adapter valve 300 has an internal thread, and the boss has a matching external thread. The internal and external threads work together to achieve a helical connection. The outer surface of the boss has an annular mounting groove 120, which houses an elastic sealing ring 121. The adapter valve 300 has an inner annular platform 330 opposite to the outer surface of the boss. When the adapter valve 300 is threadedly connected to the boss, the inner annular platform 330 of the adapter valve 300 can contact the elastic sealing ring 121 on the boss, thereby achieving a sealed connection between the adapter valve 300 and the boss. At this time, the annular mounting groove 120, the elastic sealing ring 121, and the inner annular platform 330 together constitute the sealing structure between the adapter valve 300 and the boss. Because the elastic sealing ring 121 has good elastic deformation and reset capabilities, when the adapter valve 300 moves axially towards the boss, it can compress the elastic sealing ring 121, further improving the sealing connection between the adapter valve 300 and the boss.

[0029] The aforementioned boss structure can significantly improve the structural strength of the connecting part 100 itself, withstand multiple disassembly and assembly operations without easily deforming or being damaged, and is suitable for application scenarios with sufficient external installation space.

[0030] Another implementation is that the connecting part 100 is recessed inward relative to the top cover 620 away from the outer plate surface 621 of the battery cell 700, thereby forming a recessed structure. The first through hole 110 is provided through the center of the inner bottom surface of the recess, and the transfer valve 300 extends into the recess and is movably connected to the inner wall of the recess.

[0031] In this embodiment, the adapter valve 300 has an external thread on its exterior and a matching internal thread on its interior recess. The two are connected spirally through the engagement of these threads. A limiting platform is located at the root of the external thread of the adapter valve 300. The size of the limiting platform is larger than the size of the internal thread in the recess. An elastic sealing ring 121 is located at the root of the external thread on the limiting platform. When the adapter valve 300 is threaded into the recess, the elastic sealing ring 121 is clamped between the limiting platform and the recess, thus achieving a sealed connection between the adapter valve 300 and the recess. Because the elastic sealing ring 121 has good elastic deformation and recovery capabilities, when the adapter valve 300 moves axially towards the recess, the limiting platform of the adapter valve 300 can compress the elastic sealing ring 121, causing it to deform and further enhancing the sealing connection between the adapter valve 300 and the recess.

[0032] The aforementioned recessed structure allows the pressure relief unit 200 to be fully embedded within the internal area of ​​the outer casing 600, significantly reducing the protrusion of the pressure relief unit 200 on the outside of the individual battery. This effectively saves space occupied by the individual battery and the assembly space within the battery pack, resulting in a neater and more orderly overall shape for the individual battery. Simultaneously, the recessed structure provides physical restraint and external protection for the adapter valve 300, reducing the risk of damage to the pressure relief unit 200 from external collisions, compression, or contact with foreign objects. Compared to the boss structure, the recessed structure offers advantages in space utilization, structural protection, and aesthetic neatness. The recessed structure prioritizes space compactness and structural protection reliability, while the boss structure prioritizes ease of disassembly and assembly and accessibility for later maintenance. The choice between the two can be flexibly made based on the design requirements, installation environment, and usage scenarios of different individual battery models.

[0033] In addition, the pressure relief unit 200, as the core structure for realizing gas diversion, storage and pressure relief, includes a transfer valve 300 and an airbag 400. The transfer valve 300 can be made of metal materials, and the airbag 400 is made of a flexible, high-temperature resistant, electrolyte corrosion resistant and airtight polymer material. Specifically, it can be silicone, fluororubber, polytetrafluoroethylene composite film or modified polypropylene material. The airbag 400 has a certain expansion and contraction capacity and can undergo elastic deformation under the action of internal air pressure to accommodate more gas. At the same time, it must meet the condition of long-term use without damage or leakage.

[0034] like Figure 3 and Figure 6As shown, specifically, the transfer valve 300 includes a main body 310 and a valve plate 320. The main body 310 is movably connected to the connecting part 100 and can generate relative movement. The valve plate 320 is disposed in the inner cavity of the main body 310 and can be integrally formed or welded to the main body 310, or it can be fixed inside the main body 310 as an independent sheet structure by means of snap-fit, thread, or adhesive. The valve plate 320 has a plurality of second through holes 321 extending along its thickness direction. The opening positions of the second through holes 321 can be distributed around the central area of ​​the valve plate 320. The main body 310 has a flow channel 301 that connects the first through hole 110 and the second through hole 321. The flow channel 301 is the only effective passage for the gas inside the first chamber 630 to flow to the airbag 400.

[0035] Next, the airbag 400 is detachably connected to the end of the adapter valve 300 opposite to the connecting part 100. Specific implementation methods for the detachable connection include threaded connection, snap-fit ​​connection, quick-connect fitting, clamp locking, and flange connection. In this embodiment, the detachable connection between the airbag 400 and the adapter valve 300 can be achieved using clamp locking. For this purpose, the main body 310 has a sleeve 340 at the end opposite to the connecting part 100 for fitting into the inlet end of the airbag 400. After the inlet end of the airbag 400 is fitted into the sleeve 340 of the main body 310, the screws on the clamp are tightened, causing the clamp to tighten around the inlet end of the airbag 400, thereby achieving a sealed and reliable connection between the airbag 400 and the adapter valve 300. At this time, the second chamber 410 inside the airbag 400 and the second through hole 321 on the valve plate 320 are always in direct communication, so that the gas in the guide channel 301 can enter the second chamber 410 of the airbag 400 without obstruction for storage, buffering and pressure stabilization, avoiding the direct emission of gas to the external environment and causing safety hazards or environmental pollution.

[0036] The seal 500, as the core actuator controlling the on / off state of the flow channel 301, is integrally disposed within the flow channel 301 between the valve plate portion 320 and the connecting portion 100. Specifically, the seal 500 can be a rubber sealing plug, a fluororubber gasket, a polytetrafluoroethylene sealing block, or a foamed sealing body. The seal 500 can achieve the connection or disconnection between the first through hole 110 and the second through hole 321 under the driving action of relative movement between the transfer valve 300 and the connecting portion 100.

[0037] Specifically, the transfer valve 300 can move relative to the connecting part 100, thus giving the transfer valve 300 a first position and a second position. When the transfer valve 300 switches to the first position, the sealing element 500 is in a state that enables the first through hole 110 and the second through hole 321 to conduct. The trace gases generated by the battery cell 700 during normal charge and discharge cycles, the gases generated by the long-term aging of the battery cell 700, and the by-product gases generated by the decomposition of lithium salts during the self-repair technology process can all pass sequentially through the first chamber 630, the first through hole 110, the guide channel 301, and the second through hole 321. The air bladder 400 continuously enters the second chamber 410 through the hole 321, achieving continuous dynamic depressurization of the internal air pressure of the battery cell 700. This prevents the internal air pressure of the battery cell 700 from accumulating and increasing before reaching the burst threshold of the traditional explosion-proof valve. This effectively eliminates the long-term force of continuous internal pressure on the outer shell 600 and the explosion-proof valve structure, ensuring the overall dimensional stability of the single battery cell and preventing problems such as bulging, expansion, and deformation of the battery cell 700. At the same time, it significantly improves the long-term reliability of the explosion-proof valve and avoids the risk of fatigue failure, poor sealing, or premature bursting of the explosion-proof valve due to long-term exposure to alternating air pressure.

[0038] When the airbag 400 needs to be disassembled and replaced due to prolonged use or saturation of internal gas, the relative movement between the transfer valve 300 and the connecting part 100 is controlled to switch the transfer valve 300 to the second position. At this time, the sealing element 500 is in a state that isolates the first through hole 110 from the second through hole 321. The first chamber 630 of the outer shell 600 and the second chamber 410 of the airbag 400 are completely isolated, forming two independent sealed spaces. Disassembly, replacement or maintenance of the airbag 400 in this state will not cause leakage of electrolyte inside the outer shell 600, nor will it allow external air, moisture or impurities to enter the first chamber 630 of the outer shell 600. This truly achieves non-destructive venting of the individual battery and non-destructive replacement of the airbag 400, greatly improving the maintenance convenience, safety and overall service life of the individual battery.

[0039] To further enhance structural adaptability and usage flexibility, the seal 500 can be selectively connected and fixed to the transfer valve 300 or to the connecting part 100. The relative motion between the transfer valve 300 and the connecting part 100 includes at least axial linear motion, circumferential rotational motion, and axial helical motion.

[0040] For example, when using axial linear motion, the transition valve 300 can reciprocate linearly along the central axis of the first through hole 110. The valve plate portion 320 has a first surface 322 facing the first through hole 110. The sealing member 500 is fixedly connected to the first surface 322. The orthographic projection of the sealing member 500 on the connecting portion 100 covers the orthographic projection of the first through hole 110 on the connecting portion 100. As the transition valve 300 gradually approaches the connecting portion 100 axially, the sealing member 500 moves linearly along with it and gradually presses against the outer opening of the first through hole 110, eventually completely sealing the first through hole 110 to achieve isolation between the first through hole 110 and the second through hole 321. As the transition valve 300 gradually moves away from the connecting portion 100 axially, the sealing member 500 separates from the first through hole 110 and forms a first flow guide gap 302 between them. The first flow guide gap 302 restores the communication between the flow guide channel 301 and the first through hole 110 to achieve continuous pressure relief. To limit the axial position between the transfer valve 300 and the connecting part 100, they can be fixed by welding. When the airbag 400 needs to be replaced, the weld is broken and the transfer valve 300 is pressed against the connecting part 100, thereby sealing the first through hole 110 through the sealing element 500.

[0041] Conversely, the connecting part 100 is provided with a second surface 130 facing the second through hole 321, and the sealing member 500 can also be fixedly connected to the second surface 130 of the connecting part 100. Unlike the previous embodiment, the second through hole 321 is provided in the central region of the valve plate part 320. At this time, the orthographic projection of the sealing member 500 on the valve plate part 320 covers the orthographic projection of the second through hole 321 on the valve plate part 320. As the transfer valve 300 gradually approaches the connecting part 100 along the axial direction, the second through hole 321 on the valve plate part 320 moves together with the transfer valve 300 to gradually press against the sealing member 500. Finally, the sealing member 500 completely blocks the second through hole 321 to achieve the isolation between the first through hole 110 and the second through hole 321. As the transfer valve 300 gradually moves away from the connecting part 100 along the axial direction, the sealing member 500 and the second through hole 321 separate from each other and form a second flow guide gap between them. The second flow guide gap allows the flow guide channel 301 to resume communication with the second through hole 321 to achieve continuous pressure relief.

[0042] For example, when using circumferential rotation, the transfer valve 300 can rotate circumferentially relative to the connecting portion 100 around a common central axis. The sealing member 500 is fixedly connected to the first surface 322 of the valve plate portion 320. The sealing member 500 rotates with the rotation of the valve plate portion 320, and the first through hole 110 is located on the movement path of the sealing member 500. When the transfer valve 300 rotates to a position where the sealing member 500 and the first through hole 110 are directly opposite each other, the sealing member 500 completely blocks the first through hole 110 to isolate the first through hole 110 from the second through hole 321. When the transfer valve 300 rotates to a position where the sealing member 500 and the first through hole 110 are offset from each other and a first flow guide gap 302 is formed between them, the first flow guide gap 302 restores the communication between the flow guide channel 301 and the first through hole 110 to achieve continuous pressure relief.

[0043] Conversely, the seal 500 can also be fixedly connected to the second surface 130 of the connecting part 100. The second through hole 321 on the valve plate part 320 rotates together with the transfer valve 300. At this time, the seal 500 is located on the movement path of the second through hole 321. When the transfer valve 300 rotates to a position where the second through hole 321 and the seal 500 are directly opposite each other, the seal 500 completely blocks the second through hole 321 to achieve isolation between the first through hole 110 and the second through hole 321. When the transfer valve 300 rotates to a position where the second through hole 321 and the seal 500 are offset from each other and a second flow guide gap is formed between them, the second flow guide gap restores the connection between the flow guide channel 301 and the second through hole 321 to achieve continuous pressure relief.

[0044] For example, when using axial helical motion, the transition valve 300 can reciprocate helically along the central axis of the first through hole 110. The sealing member 500 is fixedly connected to the first surface 322 of the valve plate portion 320. The sealing member 500 is located at the rotation center of the valve plate portion 320, and the orthographic projection of the sealing member 500 on the connecting portion 100 covers the orthographic projection of the first through hole 110 on the connecting portion 100. As the transition valve 300 gradually approaches the connecting portion 100 axially, the sealing member 500 moves axially helically and gradually presses against the outer opening of the first through hole 110, eventually completely sealing the first through hole 110, thereby achieving the isolation between the first through hole 110 and the second through hole 321. The structure at this time can be referred to the attached diagram. Figure 5 As the transfer valve 300 gradually moves away from the connecting part 100 along the axial direction, the sealing element 500 separates from the first through hole 110, forming a first flow guide gap 302 between them. The first flow guide gap 302 restores the connection between the flow guide channel 301 and the first through hole 110 to achieve continuous pressure relief. The structure at this time can be referred to the attached diagram. Figure 3 .

[0045] Conversely, the seal 500 can also be fixedly connected to the second surface 130 of the connecting portion 100. Unlike the previous embodiment, the second through hole 321 is located at the rotation center of the valve plate portion 320. In this case, the orthographic projection of the seal 500 on the valve plate portion 320 covers the orthographic projection of the second through hole 321 on the valve plate portion 320. As the transfer valve 300 gradually approaches the connecting portion 100 along the axial direction, the second through hole 321 on the valve plate portion 320 moves together with the transfer valve 300 to gradually press against the seal 500. Finally, the seal 500 completely blocks the second through hole 321 to achieve the isolation between the first through hole 110 and the second through hole 321. As the transfer valve 300 gradually moves away from the connecting portion 100 along the axial direction, the seal 500 and the second through hole 321 separate from each other and form a second flow guide gap between them. The second flow guide gap allows the flow guide channel 301 to resume communication with the second through hole 321 to achieve continuous pressure relief.

[0046] The aforementioned multiple relative motion modes enable this pressure relief unit 200 to adapt to application scenarios with different structural spaces, assembly requirements, and operating habits, effectively expanding the product's applicability and enhancing structural design flexibility. In the embodiment where the seal 500 is connected and fixed to the adapter valve 300, the opening position of the first through hole 110 is precisely on the movement path of the seal 500, ensuring that the seal 500 can stably reach the sealing position during movement. When the adapter valve 300 and the connecting part 100 are connected by axial insertion or threaded connection, the orthographic projection range of the seal 500 on the end face of the connecting part 100 completely covers the orthographic projection range of the first through hole 110 on the end face of the connecting part 100, ensuring that the seal 500 can completely seal the first through hole 110, avoiding problems such as local air leakage and incomplete sealing. When the transfer valve 300 and the connecting part 100 adopt a circumferential rotational motion, the sealing element 500 and the first through hole 110 no longer rely on the orthographic projection coverage relationship to achieve sealing, but achieve the sealing of the first through hole 110 by controlling the movement stroke.

[0047] In the embodiment where the seal 500 is fixed to the connecting part 100, the seal 500 is positioned precisely on the movement path of the second through hole 321, ensuring that the second through hole 321 can form a sealing relationship with the seal 500 during movement. When the adapter valve 300 and the connecting part 100 are connected by axial insertion or threaded connection, the orthographic projection range of the seal 500 on the surface of the valve plate 320 completely covers the orthographic projection range of the second through hole 321 on the surface of the valve plate 320, ensuring that the seal 500 can completely seal the second through hole 321. When the adapter valve 300 and the connecting part 100 adopt a circumferential rotational movement, the sealing between the seal 500 and the second through hole 321 no longer relies on the orthographic projection coverage relationship for sealing, but rather achieves sealing of the second through hole 321 by controlling the movement stroke.

[0048] like Figure 3 and Figure 4 As shown, to further realize intelligent monitoring and safety warning of the pressure relief status of the battery cell 700, the single battery in this embodiment also includes a detection unit (not shown in the figure) for detecting parameters of the airbag 400. The specific implementation of the detection unit includes at least a pressure sensor, a vision sensor, and a photoelectric sensor. The pressure sensor, as an optional implementation, can be selectively installed in the second chamber 410 of the airbag 400 and / or the first chamber 630 of the outer shell 600. The pressure sensor can collect gas pressure values ​​in real time and indirectly determine the expansion degree of the airbag 400, the gas production rate of the battery cell 700, and the working status of the pressure relief unit 200 through the trend of pressure changes. When the detected pressure value exceeds a preset safety threshold, the pressure sensor can output an electrical signal to trigger a warning, reminding the user that the airbag 400 is about to saturate or that the gas production of the battery cell 700 is abnormal. If the single battery is used in an automotive power battery, this warning is mainly displayed to the user through the malfunction indicator light on the car's dashboard to clearly indicate the risk of use.

[0049] Regarding the configuration of the vision sensor, the volume of the airbag 400 changes significantly during inflation, for example, relative to... Figure 3 The airbag 400 shown Figure 4 The airbag 400 shown will expand outward after being subjected to air pressure. Therefore, the visual sensor can capture the shape, size and expansion outline of the airbag 400 in real time through a miniature camera lens. Combined with the image recognition algorithm, the captured image is analyzed and processed to accurately determine the real-time volume change, expansion uniformity and whether there are abnormal states such as damage, leakage, or over-inflation of the airbag 400, thus realizing non-contact visual monitoring.

[0050] Regarding the configuration of the photoelectric sensor, it achieves non-contact detection through the cooperation of the optical path transmitter and receiver. As the gas inside the airbag 400 gradually increases and expands, the outer wall of the airbag 400 gradually approaches and blocks the emission path of the photoelectric sensor, causing a significant change in the intensity of the light signal received by the optical path receiver. The control system accurately judges the expansion size and inflation degree of the airbag 400 based on the amplitude and rate of change of the light signal, achieving real-time monitoring with high response speed and high stability. The above-mentioned multiple detection units can be used individually or in any combination. Through multi-dimensional monitoring, the accuracy and reliability of the airbag 400 status judgment are further improved, providing data support for the Battery Cell 700 intelligent safety management system.

[0051] For example, within a structural framework where the seal 500 is mounted on the valve plate portion 320, the connecting portion 100 has a boss structure, and the adapter valve 300 is screwed to the connecting portion 100, the complete workflow of this single battery cell is described in detail. This includes the assembly and installation process, the normal pressure relief process, the saturation detection of the airbag 400, and the airbag 400 replacement process. This ensures that each step is implemented in detail, clarifying the operational logic and coordination relationships of each component, as detailed below: The first step is the assembly and installation process, which is fundamental to the normal operation of the pressure relief unit 200. This process ensures that all components are reliably connected and properly sealed. The specific steps are as follows: The first step is to embed the elastic sealing ring 121 into the annular mounting groove 120 of the second surface 130 of the boss, ensuring that the sealing ring fits completely against the inner wall of the annular mounting groove 120 without any offset or wrinkles. Since the boss and the top cover 620 of the outer shell 600 are integrally formed structures, the installation and configuration of the connecting part 100 is now complete.

[0052] The second step is to fix the sealing element 500 on the first surface 322 of the valve plate part 320. The sealing element 500 is bonded and fixed with high temperature structural adhesive. After bonding, ensure that the center of the sealing element 500 is aligned with the center of the valve plate part 320, and that the size of the sealing element 500 is not smaller than the size of the first through hole 110. The orthogonal projection of the sealing element 500 on the boss can completely cover the first through hole 110 to avoid air leakage during subsequent sealing. Since the valve plate part 320 and the main body part 310 are integrally formed structures, the installation and configuration of the adapter valve 300 is now complete.

[0053] The third step is to connect the adapter valve 300 to the boss via threads. Holding the adapter valve 300, align the internal thread of the adapter valve 300 with the external thread of the boss, and slowly rotate the adapter valve 300 clockwise. During the rotation, observe the fit between the adapter valve 300 and the boss to ensure that the inner ring 330 of the adapter valve 300 can smoothly press the elastic sealing ring 121 on the boss until the adapter valve 300 rotates to the preset position. At this time, the sealing gap between the adapter valve 300 and the boss is completely filled by the elastic sealing ring 121, achieving a reliable seal. At the same time, the sealing element 500 and the second surface 130 of the boss maintain a preset gap to ensure that the first through hole 110 and the second through hole 321 are interconnected.

[0054] Fourth, slide the inlet end of the airbag 400, together with the clamp, onto the platform 340 of the transfer valve 300. After ensuring that the airbag 400 is properly fitted and secure, tighten the screws on the clamp to evenly tighten the inlet end of the airbag 400, thus achieving a sealed connection between the airbag 400 and the transfer valve 300. At this point, the second chamber 410 of the airbag 400 is fully connected to the second through hole 321 of the valve plate 320. The entire assembly and installation process is complete, and the pressure relief unit 200 enters the standby state and can be put into use at any time.

[0055] Secondly, there is the normal pressure relief workflow, which is the core operation of the pressure relief unit 200. This workflow primarily ensures continuous pressure relief throughout the entire lifecycle of the battery cell 700, preventing internal pressure accumulation. Specifically, when a single battery cell is in a normal charge-discharge cycle, a small amount of reactive gas is generated inside. Simultaneously, as the battery cell's usage time accumulates, the electrolyte inside the cell 700 gradually ages and decomposes, also generating a small amount of gas. Furthermore, during the cell 700's self-repair process, lithium salt decomposition produces byproduct gas. All these gases gradually accumulate inside the outer casing 600, causing the pressure in the first chamber 630 to slowly increase. When the pressure in the first chamber 630 rises to a level greater than the external atmospheric pressure but less than the explosion threshold of a traditional explosion-proof valve, the gas, under the influence of the pressure difference, is discharged from the first chamber 630 through the first through-hole 110 of the boss and enters the guide channel 301 of the transfer valve 300. Since the transfer valve 300 and the boss are in a screw-sealed state at this time, the gas cannot leak from the gap between them and can only continue to flow along the guide channel 301. After passing through the second through hole 321 on the valve plate 320, it finally enters the second chamber 410 of the airbag 400. The airbag 400 will slowly expand under the action of the gas, using its own elastic deformation to accommodate more gas, while buffering and stabilizing the gas, preventing the gas from being directly discharged into the external environment and causing safety hazards. During this process, the seal 500 is always fixed on the valve plate 320, and the seal 500 and the first through hole 110 always maintain a preset gap, ensuring that the first through hole 110 and the second through hole 321 are interconnected, and the gas can continuously and stably enter the airbag 400. At the same time, the detection unit works in real time. When the parameters of the airbag 400 are detected to be within the preset safety range, the pressure relief unit 200 continues to maintain the normal pressure relief state until the gas inside the airbag 400 accumulates to a near saturation state, or the gas generation rate inside the battery cell 700 becomes abnormal.

[0056] Next is the airbag 400 saturation testing and replacement process. This process enables the non-destructive replacement of the airbag 400 and ensures the continuous normal operation of the depressurization unit 200. The specific steps are as follows: The first step is that when the gas inside the airbag 400 accumulates to saturation, the air pressure inside the airbag 400 will reach a preset threshold. At this time, the air pressure sensor collects the air pressure signal and transmits the electrical signal to the control system. The control system triggers an early warning prompt, which can be communicated to the user through the device dashboard, indicator lights or remote terminal, prompting the user to replace the airbag 400.

[0057] The second step is to rotate the transfer valve 300 clockwise. Since the transfer valve 300 and the boss are screwed together, during the rotation, the transfer valve 300 will gradually approach the boss along the central axis of the boss. The sealing member 500 fixed on the valve plate part 320 will move axially with the transfer valve 300 and gradually approach the surface of the boss until the sealing member 500 is completely pressed against the outer opening of the first through hole 110. The first through hole 110 is completely blocked by the sealing member 500. The first chamber 630 of the outer shell 600 and the second chamber 410 of the air bag 400 form two independent sealed spaces to ensure that the electrolyte inside the battery cell 700 will not leak and that external air will not enter the battery cell 700.

[0058] Third, loosen the screws on the clamp and pull the old airbag 400 off the socket 340 of the adapter valve 300. Be gentle during disassembly to avoid damaging the socket 340 of the adapter valve 300 or the airbag 400 interface. After disassembly, dispose of the old airbag 400 properly to avoid electrolyte residue causing pollution.

[0059] Fourth step, put the inlet end of the new airbag 400 onto the sleeve 340 of the adapter valve 300, ensuring that it is properly fitted, then put the clamp back onto the connection, tighten the clamp screw, so that the clamp evenly tightens the inlet end of the airbag 400, ensuring a reliable seal and no air leakage.

[0060] Fifth step, rotate the transfer valve 300 counterclockwise so that the transfer valve 300 moves away from the boss along the axial direction. The seal 500 moves together with the transfer valve 300 and gradually separates from the first through hole 110 until the transfer valve 300 rotates to the preset position. At this time, the first through hole 110 and the second through hole 321 are connected, and the pressure relief unit 200 resumes normal pressure relief operation. This completes the replacement process of the airbag 400.

[0061] like Figure 1 As shown, the outer casing 600 includes a housing 610 and a top cover 620. In addition to the connecting part 100, the top cover 620 also has two electrode posts 640. The two electrode posts 640 are fixedly connected to the preset installation position of the top cover 620 by welding, riveting, injection molding, or a composite connection method. An insulating and sealing structure is provided between the electrode posts 640 and the top cover 620 to prevent electrical short circuits or sealing failures. The top cover 620 and the housing 610 are assembled together by laser welding, cold pressing welding, structural adhesive bonding, or mechanical locking to form a sealed and structurally stable container. The container internally houses the core components, electrolyte, diaphragm, and other core functional structures.

[0062] To provide double protection, an explosion-proof valve (not shown in the attached diagram) is additionally connected to the surface of the top cover 620. The explosion-proof valve adopts a one-time burst-type emergency pressure relief structure, with an internal valve core structure. The valve core can be a metal rupture disc, a spring-loaded valve core, a fusible alloy valve core, or a pressure-sensing valve core. When the cell 700 generates a large amount of gas instantaneously due to abnormal conditions such as overcharging, over-discharging, internal short circuit, or external compression, causing the internal gas pressure to rise sharply and reach the burst threshold, the explosion-proof valve ruptures, deforms, or opens under high pressure, putting the entire explosion-proof valve in a conductive state and achieving rapid emergency pressure relief. The explosion-proof valve and the pressure relief unit 200 form a dual safety protection mechanism. Under normal conditions, the pressure relief unit 200 continuously discharges a small amount of gas to prevent gas pressure accumulation. Under abnormal high pressure, the explosion-proof valve quickly activates for emergency pressure relief. The dual pressure relief mechanisms work together and complement each other, further enhancing the thermal runaway protection capability of the individual battery and minimizing the safety risks of individual battery fire and explosion.

[0063] It should be further noted that the airbag 400 should be selected with a pressure-bearing capacity greater than the burst threshold of the explosion-proof valve to prevent the airbag 400 from being burst by high-pressure gas before the explosion-proof valve is activated for emergency pressure relief, which would prevent the explosion-proof valve from performing explosion-proof operations.

[0064] This invention also provides a battery pack comprising the aforementioned multiple individual batteries. The battery pack also includes a battery module bracket, a wiring harness management unit, a battery management system, a thermal management system, a structural protective shell 600, and high-voltage circuit components. The multiple individual batteries are combined in series, parallel, or mixed connections to form a battery module. The dual configuration of the pressure relief unit 200 and the explosion-proof valve makes the individual batteries more stable and reliable when operating inside the battery pack, preventing bulging and deformation due to internal pressure accumulation that could affect module spacing and assembly accuracy. The removable and replaceable airbag 400 facilitates maintenance and upkeep of the battery pack during later use, effectively extending the overall service life and cycle stability of the battery pack and improving its safety.

[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0066] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A single-cell battery, characterized in that, include: The outer casing (600) includes a connecting portion (100) having a first through hole (110) and the outer casing (600) having a first chamber (630) communicating with the first through hole (110); The battery cell (700) is located inside the first chamber (630); The pressure relief unit (200) includes a transfer valve (300) and an airbag (400). The transfer valve (300) is movably connected to the connecting part (100), and the airbag (400) is connected to the end of the transfer valve (300) opposite to the connecting part (100). The airbag (400) has a second chamber (410). The transfer valve (300) is movable relative to the connecting part (100) to have a first position and a second position. When the transfer valve (300) is switched to the first working position, the transfer valve (300) connects the first chamber (630) and the second chamber (410); when the transfer valve (300) is switched to the second working position, the transfer valve (300) disconnects the first chamber (630) and the second chamber (410).

2. The single-cell battery according to claim 1, characterized in that, The transfer valve (300) includes a main body (310) and a valve plate (320). The valve plate (320) is fixedly connected to the main body (310) and has a second through hole (321). The main body (310) is movably connected to the connecting part (100). The main body (310) has a flow channel (301) and a sealing element (500) is provided in the flow channel (301). When the transfer valve (300) is switched to the first working position, the flow channel (301) connects the first through hole (110) and the second through hole (321) with the clearance of the sealing element (500). When the transfer valve (300) is switched to the second working position, the sealing element (500) blocks the first through hole (110), the second through hole (321), or the flow channel (301).

3. The single-cell battery according to claim 2, characterized in that, When the main body (310) and the connecting part (100) are movably connected, they can perform any one of the following relative movements: linear movement along the axial direction of the first through hole (110), rotational movement along the circumferential direction of the first through hole (110), and spiral movement along the axial direction of the first through hole (110).

4. The single-cell battery according to claim 2 or 3, characterized in that, The sealing element (500) is connected to the transfer valve (300). When the transfer valve (300) is switched to the first working position, there is a first flow guide gap (302) between the sealing element (500) and the first through hole (110). The first flow guide gap (302) connects the first through hole (110) and the flow guide channel (301). When the transfer valve (300) is switched to the second working position, the sealing element (500) blocks the first through hole (110).

5. The single-cell battery according to claim 4, characterized in that, The valve plate portion (320) has a first surface (322) facing the first through hole (110), the first surface (322) has a central region and a peripheral region located outside the central region, the central region is connected to the seal (500), and the peripheral region has a plurality of second through holes (321).

6. The single-cell battery according to claim 2 or 3, characterized in that, The sealing element (500) is connected to the connecting part (100). When the switching valve (300) is switched to the first working position, there is a second flow guiding gap between the sealing element (500) and the second through hole (321). The second flow guiding gap connects the second through hole (321) and the flow guiding channel (301). When the switching valve (300) is switched to the second working position, the sealing element (500) blocks the second through hole (321).

7. The single-cell battery according to claim 1, characterized in that, The airbag (400) is detachably connected to the adapter valve (300).

8. The single-cell battery according to claim 1, characterized in that, The housing (600) also includes a top cover (620) having an outer plate surface (621) facing away from the battery cell (700), and the connecting portion (100) protruding outward relative to the outer plate surface (621) or recessed inward relative to the outer plate surface (621).

9. The single-cell battery according to claim 1, characterized in that, It also includes a detection unit for detecting the size of the airbag (400), the detection unit including a pressure sensor disposed in the second chamber (410) and / or the first chamber (630).

10. A battery pack, characterized in that, The battery pack comprises the individual cells as described in any one of claims 1 to 9.

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