Explosion-proof breather valve for power battery

Abstract

The utility model relates to an explosion-proof ventilation valve for a power battery, which comprises a valve body, a ventilation film and a protective cover, two corresponding ends of the valve body are respectively provided with an air inlet end and an air outlet end, the air inlet end face of the valve body is provided with an air inlet cavity, the air outlet end face of the valve body is provided with an exhaust pipe communicated with the air inlet cavity, and a cross is arranged in the air inlet cavity. The intersection part of the cross shields the center of the inner opening of the exhaust pipe, so that the inner opening of the exhaust pipe is equally divided into four air inlet holes with the same size; the breathable film is arranged in the air inlet cavity and tightly attached to the cross so as to seal the four air inlet holes of the exhaust pipe, and the breathable film is provided with micro holes through which air can pass but liquid and fixed particles cannot pass. The protective cover is fixedly arranged at the air inlet end of the valve body, and an air inlet gap is formed between the protective cover and the valve body. According to the utility model, the internal and external pressure difference in the power battery pack can be kept balanced, and the power battery pack is prevented from exploding due to overlarge internal and external pressure difference.

Description

Technical Field

[0001] The utility model relates to a power battery, in particular to a vent valve for the power battery. Background Art

[0002] With the development of new energy vehicles, power batteries, as key components, are receiving increasing attention. Power batteries operate under complex conditions for extended periods of time. The heating and cooling processes of the internal cells, as well as changes in the external environment, can all lead to pressure imbalances inside and outside the battery pack. When the pressure inside the battery pack exceeds the pressure outside, it can cause the battery case to swell, even impacting the proper functioning of electrical components and, in extreme cases, causing the battery pack to explode. When the pressure inside the battery pack is lower than the pressure outside, a breathing effect occurs, compromising the seal. Therefore, the vent valve is a critical component in power batteries. Utility Model Content

[0003] The utility model aims to provide an explosion-proof vent valve for a power battery.

[0004] The technical solution of the utility model is as follows:

[0005] A explosion-proof air valve for a power battery comprises a valve body, a breathable membrane and a protective cover, wherein the corresponding two ends of the valve body are respectively arranged as an air inlet end and an air outlet end, and the air inlet end face is provided with an air inlet cavity, and the air outlet end face is provided with an exhaust pipe connected to the air inlet cavity, and a cross is provided in the air inlet cavity, and the intersection of the cross is blocked at the center of the inner opening of the exhaust pipe to divide the inner opening of the exhaust pipe into four air inlet holes of equal size; the breathable membrane is provided in the air inlet cavity and fits tightly on the cross to close the four air inlet holes of the exhaust pipe, and the breathable membrane is provided with micropores through which air can pass but liquid and fixed particles cannot pass; the protective cover is fixedly provided at the air inlet end of the valve body and separated from the valve body by an air inlet gap.

[0006] As a preferred solution, the cross is arc-shaped and convex toward the air inlet end of the valve body to form a pressure-bearing arc surface.

[0007] As a preferred solution, the valve body includes an integrally injection-molded cylinder and an exhaust pipe. The two ends of the cylinder are respectively set as the air inlet end and the air outlet end, and a circular air inlet cavity is provided in the center of the air inlet end face. The exhaust pipe is upright in the center of the air outlet end face of the cylinder.

[0008] As a preferred solution, a circular groove with a diameter larger than that of the inner opening of the exhaust pipe is provided in the center of the inner wall of the air inlet cavity. The exhaust pipe passes directly through the center of the circular groove. A cross is provided on the inner groove wall of the circular groove, and a breathable membrane is provided in the circular groove.

[0009] As a preferred solution, the periphery of the breathable membrane is sealed and pressed and fixed inside the side wall of the circular groove.

[0010] As a preferred solution, the exhaust pipe directly passes through the center of the air intake cavity, the cross is provided on the inner wall of the air intake cavity, and the periphery of the breathable membrane is welded and bonded to the inner wall of the air intake cavity.

[0011] As a preferred solution, a pressure ring is further provided in the air inlet cavity for pressing and fixing the periphery of the breathable membrane onto the valve body.

[0012] As a preferred solution, the pressure ring is pressed and fixed in the air inlet cavity by the protective cover, so as to press the periphery of the breathable membrane against the inner wall of the air inlet cavity.

[0013] As a preferred solution, the inner surface protrusion of the protective cover is a circular boss that gradually shrinks inward. The large bottom circle diameter of the circular boss is larger than the cavity diameter of the air intake cavity, and the small bottom circle diameter is smaller than the cavity diameter of the air intake cavity. The protective cover is fixedly connected to the valve body by a number of clips arranged around the circular boss and annular grooves provided on the inner wall of the air intake cavity, and an air intake gap is separated between the circular boss and the valve body.

[0014] As a preferred solution, a sealing ring is sleeved on the exhaust pipe.

[0015] This utility model incorporates a breathable membrane within the valve body that ruptures automatically when the pressure differential between the two sides exceeds a set limit. Applied to the exhaust structure of a power battery pack, this membrane balances the internal and external pressure differential within the battery pack, preventing explosions caused by excessive internal and external pressure differentials. Furthermore, this utility model is waterproof and dustproof. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the overall structure of an embodiment of the present utility model from a certain angle;

[0017] Figure 2 This is a schematic diagram of the overall structure of an embodiment of the utility model from another angle;

[0018] Figure 3 This is an exploded view of the overall structure of the first embodiment of the present utility model;

[0019] Figure 4 This is a cross-sectional view of the overall structure of Example 1 of the present utility model;

[0020] Figure 5 This is a schematic diagram of the valve body structure of Example 1 of the present utility model;

[0021] Figure 6 This is a schematic diagram of the protective cover structure of an embodiment of the utility model;

[0022] Figure 7 This is an exploded view of the overall structure of the second embodiment of the present utility model;

[0023] Figure 8This is a cross-sectional view of the overall structure of Example 2 of the present utility model. DETAILED DESCRIPTION

[0024] The present invention will be described below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1

[0026] Reference Figure 1-6 The explosion-proof vent valve for a power battery shown includes a valve body 1, a vent membrane 2, a protective cover 3 and a sealing ring 4.

[0027] The valve body 1 comprises an integrally injection-molded cylindrical body 1.1 and an exhaust pipe 1.2. The two ends of the cylindrical body 1.1 are respectively provided with an air inlet end and an air outlet end, and an air inlet cavity 1.11 is provided in the center of the air inlet end face. The exhaust pipe 1.2 is centrally provided on the air outlet end face of the cylindrical body 1.1. The air inlet cavity 1.11 is circular and a circular groove 1.111 having a diameter larger than that of the inner opening of the exhaust pipe 1.2 is provided in the center of the inner wall of the circular groove 1.111. The exhaust pipe 1.2 directly passes through the center of the circular groove 1.111. A cross 1.1111 is integrally formed on the inner wall of the circular groove 1.111. The cross 1.1111 is provided in the center of the inner wall of the circular groove 1.111. The intersection of 111 blocks the center of the inner opening of the exhaust pipe 1.2 to divide the inner opening of the exhaust pipe 1.2 into four air inlet holes 1.3 of equal size. The cross 1.1111 is arc-shaped and protrudes toward the air inlet end of the valve body 1 to form a pressure-bearing arc surface; the exhaust pipe 1.2 includes a straight pipe section 1.21 connected to the cylinder 1.1 and a trumpet section 1.22 provided at the outer end of the straight pipe section 1.21. The outer wall of the end of the trumpet section 1.22 is provided with a limiting convex ring 1.221. The trumpet section 1.22 is equally divided into three radially outward-warped elastic petals 1.222 to form a petal-like structure.

[0028] The breathable membrane 2 is provided with micropores through which air can pass but liquids and fixed particles cannot pass. The breathable membrane 2 is arranged in the circular groove 1.111 and fits tightly against the pressure-bearing arc surface of the cross 1.1111 to seal the four air inlet holes 1.3 of the exhaust pipe 1.2. In this embodiment, the periphery of the breathable membrane 2 is sealed and pressed and fixed to the inside of the side wall of the circular groove 1.111 by integral injection molding technology.

[0029] The protective cover 3 is provided at the air inlet end of the valve body 1. The inner surface of the protective cover 3 protrudes into a circular boss 3.1 that gradually tapers inward. The large bottom diameter of the circular boss 3.1 is larger than the diameter of the air inlet cavity 1.11, and the small bottom diameter is smaller than the diameter of the air inlet cavity 1.11. The protective cover 3 is fixedly connected to the valve body 1 by a plurality of clips 3.2 arranged around the circular boss 3.1 and engaging with an annular groove 1.112 provided on the inner wall of the air inlet cavity 1.11. An air inlet gap 5 is separated from the valve body 1.1 by a gap 5 between the circular boss 3.1 and the valve body 1.1.

[0030] The sealing ring 4 is sleeved on the exhaust pipe 1.2 on the inner side of the limiting convex ring 1.221.

[0031] Example 2

[0032] Reference Figure 1-2 6-8, the difference between the second embodiment and the first embodiment lies in the installation structure of the breathable membrane 2, which is as follows: the valve body 1 of the second embodiment does not have a circular groove 1.111, but the cross 1.1111 is integrally formed and directly arranged on the inner wall of the air inlet cavity 1.11, the exhaust pipe 1.2 passes directly through the center of the air inlet cavity 1.2, and the breathable membrane 2 is arranged in the air inlet cavity 1.11 and is tightly attached to the pressure-bearing arc surface of the cross 1.1111, so that the four air inlet holes of the exhaust pipe 1.2 are 1.3 are all closed; in order to fix the breathable membrane 2, a welding line is pre-arranged on the inner wall of the air inlet cavity 1.11, and the welding line is melted by ultrasonic welding technology to seal and bond the periphery of the breathable membrane 2 and the valve body 1 as one. In order to further fix the breathable membrane 2, a pressure ring 6 is also provided in the air inlet cavity 1.11. When the protective cover 3 is fastened, the elastic buckle 3.2 on the protective cover 3 presses the pressure ring 6 at the same time, and the pressure ring 6 presses the periphery of the breathable membrane 2 to the inner wall of the air inlet cavity 1.11.

[0033] The working principle of this utility model is as follows: Air entering through the air intake gap 5 is discharged along the breathable membrane 2 into the exhaust pipe 1.2. Liquid and solid particles carried in the air are blocked by the breathable membrane 2 within the air intake cavity 1.11 and cannot enter the exhaust pipe 1.2. During this process, because the breathable membrane 2 only contacts the pressure-bearing curved surface of the valve body 1 on one side, when the pressure from the intake direction exceeds the strength limit of the breathable membrane 2, the breathable membrane 2 in front of the air intake hole 1.3 will rupture, timely balancing the pressure on both sides. Therefore, this utility model has the functions of ventilation, waterproofing, dustproofing, and explosion-proofing. When applied to the exhaust structure of a power battery, it can better maintain the internal and external pressure balance of the power battery.

Claims

1. An explosion-proof vent valve for a power battery, comprising a valve body, a vent membrane, and a protective cover, characterized in that: The corresponding two ends of the valve body are respectively arranged as the air inlet end and the air outlet end, and the air inlet end face is provided with an air inlet cavity, and the air outlet end face is provided with an exhaust pipe connected to the air inlet cavity. A cross is provided in the air inlet cavity, and the intersection of the cross is blocked at the center of the inner opening of the exhaust pipe to divide the inner opening of the exhaust pipe into four air inlet holes of the same size; the air permeable membrane is provided in the air inlet cavity and fits tightly on the cross to close the four air inlet holes of the exhaust pipe, and the air permeable membrane is provided with micropores through which air can pass but liquid and fixed particles cannot pass; the protective cover is fixedly provided at the air inlet end of the valve body and separated from the valve body by an air inlet gap.

2. The explosion-proof vent valve for a power battery according to claim 1, characterized in that: The cross is arc-shaped and convex toward the air inlet end of the valve body to form a pressure-bearing arc surface.

3. The explosion-proof vent valve for a power battery according to claim 2, characterized in that: The valve body includes an integrally injection-molded cylinder and an exhaust pipe. The two ends of the cylinder are respectively set as the air inlet end and the air outlet end, and a circular air inlet cavity is provided in the center of the air inlet end face. The exhaust pipe is upright in the center of the air outlet end face of the cylinder.

4. The explosion-proof vent valve for a power battery according to claim 3, characterized in that: A circular groove with a diameter larger than that of the exhaust pipe inner opening is provided in the center of the inner wall of the air inlet cavity. The exhaust pipe directly passes through the center of the circular groove. A cross is provided on the inner groove wall of the circular groove. A breathable membrane is provided in the circular groove.

5. The explosion-proof vent valve for a power battery according to claim 4, characterized in that: The periphery of the breathable membrane is sealed and pressed and fixed inside the side wall of the circular groove.

6. The explosion-proof vent valve for a power battery according to claim 3, characterized in that: The exhaust pipe is directly connected to the center of the air intake cavity, the cross is arranged on the inner cavity wall of the air intake cavity, and the periphery of the breathable membrane is welded and bonded to the inner cavity wall of the air intake cavity.

7. The explosion-proof vent valve for a power battery according to claim 6, characterized in that: A pressure ring is also provided in the air inlet cavity for pressing and fixing the periphery of the breathable membrane onto the valve body.

8. The explosion-proof vent valve for a power battery according to claim 7, characterized in that: The pressure ring is pressed and fixed in the air inlet cavity by the protective cover so as to press the periphery of the breathable membrane against the inner cavity wall of the air inlet cavity.

9. The explosion-proof vent valve for a power battery according to claim 1, characterized in that: The inner surface of the protective cover is raised into a circular boss that gradually shrinks inward. The large bottom circle diameter of the circular boss is larger than the cavity diameter of the air intake cavity, and the small bottom circle diameter is smaller than the cavity diameter of the air intake cavity. The protective cover is fixedly connected to the valve body by a number of clips arranged around the circular boss and the annular groove provided on the inner wall of the air intake cavity, and an air intake gap is separated between the circular boss and the valve body.

10. The explosion-proof vent valve for a power battery according to claim 1, characterized in that: A sealing ring is sleeved on the exhaust pipe.

Images