Corrugated pipe type breather valve of soft package lithium battery

Abstract

The utility model relates to a soft package lithium battery corrugated pipe type breather valve which comprises a valve body and a valve clack, a corrugated pipe is arranged on the outer wall of the valve body, a buffering cavity is formed in the valve body, an air inlet pipe communicated with the buffering cavity is arranged at the bottom of the valve body, and an air outlet hole communicated with the buffering cavity is formed in the top of the valve body. The two sides of the bottom of the buffering cavity are rotationally connected with valve clacks correspondingly, and the ends of the two valve clacks abut against each other and are located on the central axis of the valve body. The breather valve is mainly designed to be used for pressure relief protection after gas production of the soft package battery, the battery cell can be directly disassembled from the breather valve, the step of manually winding and disassembling the diaphragm when the battery cell is disassembled is simplified, gas generated in the battery cell can be discharged through the technical scheme of the breather valve, potential safety hazards such as bulging and breakage are reduced, and the safety of the battery cell is improved. And the service life of the soft package lithium battery is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of soft-pack lithium battery technology, and in particular to a bellows-type breather valve for soft-pack lithium batteries. Background Technology

[0002] The outer casing of a pouch lithium battery is made of an aluminum-plastic composite film, encapsulating the battery cell inside. In the event of a safety hazard, the gas generated inside the cell cannot be released in time, causing the pouch battery to swell and crack. This leads to safety risks such as casing swelling and rupture, affecting the normal use of the pouch lithium battery. However, current pouch lithium batteries do not have pressure relief devices or mechanisms on their outer casings to release the gas generated inside the cell in a timely manner. Installing a one-way valve would also affect the internal battery cell. Therefore, current pouch lithium batteries require further structural improvements to facilitate pressure relief from the cell. Utility Model Content

[0003] The purpose of this invention is to provide a bellows-type breather valve for soft-pack lithium batteries, which can promptly discharge the gas generated inside the battery cell, thereby solving the problems encountered in the background art.

[0004] To achieve the above objectives, the technical solution of this utility model is as follows:

[0005] A bellows-type breathing valve for a soft-pack lithium battery includes a valve body and valve discs. The outer wall of the valve body is provided with a bellows, and a buffer chamber is opened inside the valve body. The bottom of the valve body is provided with an air inlet pipe communicating with the buffer chamber, and the top of the valve body is provided with an air outlet communicating with the buffer chamber. Valve discs are rotatably connected to the bottom two sides of the buffer chamber, and the ends of the two valve discs abut together and are located on the central axis of the valve body.

[0006] In the above scheme, the buffer chamber is a rectangular structure, with its top connected to the air outlet and its bottom connected to the air inlet pipe; the valve disc includes a valve plate and a rotating shaft, with the rotating shaft fixed on one side of the valve plate and its length dimension being greater than the width dimension of the valve plate; shaft holes that cooperate with the rotating shaft are opened on both sides of the bottom of the buffer chamber.

[0007] As a preferred embodiment, the end of the valve plate has a semi-circular structure, the width of the valve plate is smaller than the width of the buffer cavity, and the width of the valve plate is larger than the diameter of the intake pipe. The bellows has a spindle-shaped structure, and it has at least three layers on the outer wall of the valve body, with the gaps between adjacent layers of bellows forming clearance grooves.

[0008] In the above scheme, the air intake pipe includes a bottom air intake, which is located at the bottom of the valve body and has an inverted bucket shape. The central axis of the bottom air intake coincides with the central axis of the valve body.

[0009] As a preferred embodiment, the air intake pipe further includes a side air intake, with at least two side air intakes arranged horizontally. One end of the side air intake is located on the bottom outer wall of the valve body, and the other end passes through the funnel-shaped inclined surface of the bottom air intake.

[0010] In the above scheme, a drying chamber is provided on the upper side of the valve body. The drying chamber has a cylindrical structure. The top of the drying chamber is connected to the air outlet, and the bottom of the drying chamber is connected to the air inlet pipe. A drying box is installed in the drying chamber, and a desiccant is placed in the drying box.

[0011] As a preferred embodiment, the bottom of the drying chamber is provided with a positioning groove, which is a circular groove-shaped structure. The bottom of the drying box is provided with a positioning support that mates with the positioning groove. The drying box has a hollow structure, with ventilation holes evenly distributed on its outer wall, and a handle on its top. Furthermore, the top of the drying chamber is provided with a cover plate, and the top of the valve body has a connecting groove that mates with the cover plate. The air outlet is located at the center of the cover plate and has an inverted bucket-shaped structure.

[0012] Compared with existing technologies, the beneficial effects of this invention are as follows: When using this device, when the gas accumulates to a certain amount, it reaches the valve disc through the inlet pipe, lifting the valve disc and venting the gas. After the internal pressure decreases, the valve disc falls back and closes. The buffer chamber can accumulate a portion of the gas, helping the valve disc to close, thus achieving the function of a breathing valve. This device is mainly designed for pressure relief protection after gas generation in pouch batteries. The battery cell can be directly disassembled from this breathing valve, simplifying the manual winding and removal of the separator during battery cell disassembly. Because the technical solution of this breathing valve can expel the gas generated inside the battery cell, it reduces safety hazards such as swelling and rupture, and extends the service life of pouch lithium batteries. Attached Figure Description

[0013] The disclosure of this utility model is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. In the drawings, the same reference numerals are used to refer to the same parts. Wherein:

[0014] Figure 1 This is a schematic diagram of the external structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0016] Figure 3 This is a schematic diagram of the valve disc when it is open in this utility model;

[0017] Figure 4 This is a schematic diagram of the drying box in this utility model;

[0018] Figure 5This is a schematic diagram of the valve disc structure in this utility model.

[0019] The following numbers are labeled in the diagram: 1-Valve body; 11-Bellwall; 12-Bottom air inlet; 13-Side air inlet; 14-Air inlet pipe; 15-Buffer chamber; 16-Drying chamber; 17-Positioning groove; 18-Connecting groove; 19-Allowing groove; 2-Cover plate; 21-Air outlet; 3-Valve disc; 31-Valve plate; 32-Rotating shaft; 4-Drying box; 41-Ventilation hole; 42-Positioning support; 43-Handle. Detailed Implementation

[0020] To make the technical means, creative features, achieved objectives and effects of this utility model easier to understand, the utility model will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of this utility model, and therefore only show the relevant components of this utility model.

[0021] Based on the technical solution of this utility model, without changing the essential spirit of this utility model, those skilled in the art can propose various interchangeable structural methods and implementation methods. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative descriptions of the technical solution of this utility model, and should not be regarded as the entirety of this utility model or as a limitation or restriction of the technical solution of this utility model.

[0022] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0023] Example 1, as Figure 1-3 As shown, a bellows-type breather valve for a pouch lithium battery is disclosed. This breather valve is installed within the pouch battery's encapsulation shell. The valve includes a valve body 1 and a valve disc 3. The valve body 1 is made of soft plastic, while the valve disc 3 is made of hard plastic. A bellows 11 is provided on the outer wall of the valve body 1, embedded in an aluminum-plastic composite membrane. The top of the valve body 1 is located outside the pouch lithium battery, and the bottom of the valve body 1 is located inside the cell mounting cavity of the pouch lithium battery.

[0024] The valve body 1 has a buffer chamber 15 inside, and an air inlet pipe 14 connected to the buffer chamber 15 is provided at the bottom of the valve body 1. The air inlet pipe 14 is used to collect the gas inside the soft-pack battery, and the gas enters the breathing valve through the air inlet pipe 14. The valve body 1 has an air outlet 21 connected to the buffer chamber 15 at the top, which is used to discharge the gas generated in the soft-pack lithium battery. In order to have a one-way exhaust function, valve discs 3 are rotatably connected to both sides of the bottom of the buffer chamber 15. The ends of the two valve discs 3 abut together and are located on the central axis of the valve body 1. Gas is only allowed to be discharged from the air outlet 21 through the valve discs 3, and gas is not allowed to enter the soft-pack lithium battery from the air outlet 21.

[0025] In implementation, the buffer chamber 15 has a rectangular structure, with its top connected to the air outlet 21 and its bottom connected to the air inlet pipe 14. For implementation details, please refer to [link / reference needed]. Figure 5 The valve disc 3 includes a valve plate 31 and a rotating shaft 32. The rotating shaft 32 is fixed on one side of the valve plate 31, and its length is greater than the width of the valve plate 31. The part of the rotating shaft 32 that extends out is the rotating shaft. Shaft holes that cooperate with the rotating shaft 32 are opened on both sides of the bottom of the buffer cavity 15. That is, the rotating shaft is inserted into the shaft hole so that the valve plate 31 can rotate under the push of air pressure with this as the axis.

[0026] As a preferred embodiment, the end of the valve plate 31 has a semi-circular structure, and the width of the valve plate 31 is smaller than the width of the buffer cavity 15 so that it can be opened or closed smoothly. The width of the valve plate 31 is larger than the diameter of the intake pipe 14 so that it can cover the top of the entire intake pipe 14.

[0027] Example 2, as Figure 1 As shown, based on Embodiment 1, the bellows 11 has a spindle-shaped structure to facilitate better snap-fitting or embedded installation with the outer casing of the soft-pack lithium battery. The bellows 11 has at least three layers on the outer wall of the valve body 1, providing a certain degree of sealing. Because it is made of a soft material, it possesses a certain degree of elasticity and tightness. The gap between two adjacent layers of bellows 11 forms a clearance groove 19, providing space for embedding within the aluminum-plastic composite membrane.

[0028] Example 3, please refer to Figure 1-3 Based on embodiment 1, the bottom of the air inlet pipe 14 is provided with a bottom air inlet 12. The bottom air inlet 12 is located at the bottom of the valve body 1 and has an inverted bucket shape structure, which is used to absorb and collect the gas generated by the battery cell. The central axis of the bottom air inlet 12 coincides with the central axis of the valve body 1.

[0029] As a preferred embodiment, the bottom of the air intake pipe 14 is also provided with a side air intake 13, which is a through-hole type structure. At least two side air intakes 13 are provided, and they are horizontally arranged. In implementation, one end of the side air intake 13 is opened on the bottom outer wall of the valve body 1, and the other end penetrates the funnel-shaped inclined surface of the bottom air intake 12. Depending on the needs, one side air intake 13 can be opened in front of, behind, to the left of, and to the right of the bottom air intake 12, meaning a total of four side air intakes 13, plus the bottom air intake 12, for a total of five air intake points.

[0030] In Example 4, based on Example 1, a drying chamber 16 is provided on the upper side of the valve body 1. The drying chamber 16 has a cylindrical structure, with its top connected to the air outlet 21 and its bottom connected to the air inlet pipe 14. A drying box 4 is installed in the drying chamber 16, and a desiccant is placed in the drying box 4. When the gas in the soft-pack lithium battery passes through the drying box 4, it will be dried by the desiccant. When external gas enters the drying chamber 16, it will also be dried.

[0031] As a preferred embodiment, a positioning groove 17 is provided at the bottom of the drying chamber 16. The positioning groove 17 is a circular groove-shaped structure, and the bottom of the drying box 4 is provided with a positioning support 42 that cooperates with the positioning groove 17. When the drying box 4 is placed, it is positioned by the positioning groove 17 to prevent the drying box 4 from shaking and to be located at the central axis of the valve body 1, thereby achieving a good filtration and drying effect.

[0032] Please see Figure 4 The drying box 4 has a hollow structure. Ventilation holes 41 are evenly distributed on the outer wall of the drying box 4 to facilitate the internal and external circulation of gas. The top of the drying box 4 is provided with a handle 43, which makes it easy for installers to grab the handle 43 and place the drying box 4 into the positioning groove 17.

[0033] Additionally, a cover plate 2 is provided on the top of the drying chamber 16, which can also be considered the top cover of the valve body 1. The top of the valve body 1 has a connecting groove 18 that mates with the cover plate 2. This connecting groove 18 can be a smooth slot or a threaded groove. When using a smooth slot, strong adhesive can be added inside for stable fixing of the two. When using a threaded groove, simply screwing it on will fix the two together. The vent 21 is located at the exact center of the cover plate 2. The vent 21 has an inverted bucket shape, or a funnel shape, to minimize the entry of external gas into the interior.

[0034] The following is combined Figure 1-5 The working principle of this breathing valve is explained in detail based on the structure shown and the structure described in the above scheme:

[0035] When gas is generated inside the battery cell, there are 5 air inlets at the bottom of the valve: 1 at the bottom air inlet 12 on the front bottom surface and 4 at the side air inlets 13 on the bottom side surface. When the gas accumulates to a certain amount, it reaches the valve disc 3 through the air inlet pipe 14, which lifts the valve disc 3 and discharges the gas. After the internal pressure decreases, the valve disc 3 falls back and closes. The buffer chamber 15 can accumulate some gas to help the valve disc 3 close, thus achieving the function of a breathing valve. The excess gas continues to flow to the outside and is discharged through the drying chamber 16 and the cover plate 2.

[0036] The drying chamber 16 is equipped with a drying box 4 containing desiccant; the air outlet 21 on the cover plate 2 is funnel-shaped with a sufficiently small opening to reduce external air intake; the drying box 4 has openings on three sides and the bottom positioning support 42 is raised to reduce interference from external gas.

[0037] The bellows 11 on the outer wall of the valve body 1 is designed to facilitate sealing. The clearance groove 19 avoids the deformation caused by heat sealing of aluminum-plastic film, thereby improving the yield rate. There is a connecting groove 18 between the cover plate 2 and the valve body 1, which can be fixed by thread or by welding. If injection molded parts are used, they can be fixed by adhesive.

[0038] This device is mainly designed for pressure relief protection after gas is generated in pouch batteries. The battery cell can be directly disassembled from this breather valve, simplifying the manual winding and removal of the separator when disassembling the battery cell. Because the technical solution of this breather valve can discharge the gas generated inside the battery cell, it reduces safety hazards such as swelling and rupture, and extends the service life of pouch lithium batteries.

[0039] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A bellows-type breather valve for a soft-pack lithium battery, characterized in that: The valve includes a valve body (1) and a valve disc (3). The outer wall of the valve body (1) is provided with a bellows (11). The valve body (1) has a buffer chamber (15) inside. The bottom of the valve body (1) is provided with an air inlet pipe (14) that connects to the buffer chamber (15). The top of the valve body (1) has an air outlet (21) that connects to the buffer chamber (15). The bottom sides of the buffer chamber (15) are respectively rotatably connected to valve discs (3). The ends of the two valve discs (3) abut together and are located on the central axis of the valve body (1).

2. The bellows-type breather valve for a soft-pack lithium battery according to claim 1, characterized in that: The buffer chamber (15) has a rectangular structure, with its top connected to the air outlet (21) and its bottom connected to the air inlet pipe; the valve disc (3) includes a valve plate (31) and a rotating shaft (32), the rotating shaft (32) is fixed on one side of the valve plate (31), and its length dimension is greater than the width dimension of the valve plate (31); the bottom sides of the buffer chamber (15) are provided with shaft holes that cooperate with the rotating shaft (32).

3. The bellows-type breather valve for a soft-pack lithium battery according to claim 2, characterized in that: The end of the valve plate (31) is a semi-circular structure. The width of the valve plate (31) is smaller than the width of the buffer cavity (15), and the width of the valve plate (31) is larger than the diameter of the air intake pipe.

4. The bellows-type breather valve for a soft-pack lithium battery according to claim 1, characterized in that: The bellows (11) has a spindle-shaped structure and at least three layers are provided on the outer wall of the valve body (1). The gap between two adjacent layers of bellows (11) forms a clearance groove (19).

5. A bellows-type breather valve for a soft-pack lithium battery according to claim 1, characterized in that: The top of the air intake pipe (14) is provided with a bottom air intake (12), which is located at the bottom of the valve body (1) and has an inverted bucket shape. The central axis of the bottom air intake (12) coincides with the central axis of the valve body (1).

6. A bellows-type breather valve for a soft-pack lithium battery according to claim 5, characterized in that: The top of the air intake pipe (14) is also provided with a side air intake (13). There are at least two side air intakes (13), and they are horizontally arranged. One end of the side air intake (13) is opened on the bottom outer wall of the valve body (1), and the other end passes through the bucket-shaped inclined surface of the bottom air intake (12).

7. A bellows-type breather valve for a soft-pack lithium battery according to claim 1, characterized in that: A drying chamber (16) is provided on the upper side of the inside of the valve body (1). The drying chamber (16) is a cylindrical structure. The top of the drying chamber (16) is connected to the air outlet (21), and the bottom of the drying chamber (16) is connected to the air inlet pipe. A drying box (4) is installed in the drying chamber (16), and a desiccant is placed in the drying box (4).

8. A bellows-type breather valve for a soft-pack lithium battery according to claim 7, characterized in that: The bottom of the drying chamber (16) is provided with a positioning groove (17), which is a circular groove structure. The bottom of the drying box (4) is provided with a positioning support (42) that cooperates with the positioning groove (17).

9. A bellows-type breather valve for a soft-pack lithium battery according to claim 7, characterized in that: The drying box (4) has a hollow structure, and ventilation holes (41) are evenly provided on the outer wall of the drying box (4). A handle (43) is provided on the top of the drying box (4).

10. A bellows-type breather valve for a soft-pack lithium battery according to claim 7, characterized in that: The top of the drying chamber (16) is provided with a cover plate (2), and the top of the valve body (1) is provided with a connecting groove (18) that cooperates with the cover plate (2). The air outlet (21) is located at the center of the cover plate (2) and the air outlet (21) has an inverted bucket shape.

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