Power battery cover cap for preventing high-temperature seal failure

Abstract

The utility model discloses a kind of power battery caps for preventing high-temperature sealing failure, relate to battery accessory technical field.The utility model includes cap main body, sealing assembly and convex cap, the top end central fixed with convex cap of cap main body, the inner wall lower part of cap main body is fixed with fixed sleeve, the edge of fixed sleeve inner wall lower part is fixed with lower sealing disc, the inner wall of cap main body top end of fixed sleeve is fixed with sealing assembly, sealing assembly includes fixed ring, elastic ring and upper sealing disc, the inner wall of fixed ring is fixed with elastic ring, the inner wall of elastic ring is fixed with upper sealing disc, and upper sealing disc is movably connected in fixed ring.The utility model sets up cap main body, sealing assembly and convex cap, solve the sealing failure caused by thermal expansion of battery cap internal sealing element under high-temperature environment of power battery cap, and when battery internal pressure abnormally rises, the problem of safety pressure relief and automatic reset sealing.

Description

Technical Field

[0001] This utility model belongs to the field of battery accessory technology, and in particular relates to a power battery cap that prevents high-temperature sealing failure. Background Technology

[0002] The battery cap is a precision composite component on top of a cylindrical lithium-ion battery. It is a core safety component responsible for critical functions, primarily composed of a top cover, explosion-proof sheet, PTC element, and insulating gasket. Assembled using precision processes, its core functions include conducting current as the battery's positive electrode, releasing pressure and preventing explosions through the explosion-proof sheet rupture when internal pressure is too high, providing overcurrent and overheat protection using the PTC element, and ensuring the battery's insulation and sealing. Therefore, the quality and reliability of the battery cap directly determine the safety of lithium-ion batteries and it is widely used in various power storage systems. However, the battery cap still has the following drawbacks in practical use: In the operation of traditional power batteries, the internal temperature will rise, causing the sealing components (such as sealing discs) to thermally expand. If the design is not proper, this expansion may cause the seals to deform, create gaps, or generate excessive pressure in some parts and be damaged, thereby destroying the sealing performance and causing safety hazards such as leakage and short circuit. Secondly, when a battery malfunctions (such as overcharging or internal short circuit), it will generate a large amount of gas, causing the internal pressure to rise sharply. If the pressure cannot be released in time, the battery is at risk of explosion. Traditional explosion-proof valves may not be able to automatically reset and seal after pressure relief, leading to permanent battery failure or the entry of external substances. Utility Model Content

[0003] The purpose of this utility model is to provide a power battery cap that prevents high-temperature sealing failure. By setting up a cap body, sealing components and a convex cap, it solves the problem of safe pressure relief and automatic resetting of the seal when the internal sealing component of the power battery cap fails due to thermal expansion under high temperature environment and when the internal pressure of the battery rises abnormally.

[0004] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution: This utility model relates to a power battery cap for preventing high-temperature sealing failure, comprising a cap body, a sealing assembly, and a convex cap. A convex cap is fixed to the center of the top of the cap body. A fixing sleeve is fixed to the lower part of the inner wall of the cap body. A lower sealing disc is fixed to the lower edge of the inner wall of the fixing sleeve. A sealing assembly is fixed to the inner wall of the cap body at the top of the fixing sleeve. The sealing assembly includes a fixing ring, an elastic ring, and an upper sealing disc. An elastic ring is fixed to the inner wall of the fixing ring, and an upper sealing disc is fixed to the inner wall of the elastic ring. The upper sealing disc is movably connected within the fixing ring. The cap body is connected to an external electrode via the convex cap. A fixing sleeve is provided inside the cap body. A lower sealing disc is fixed to the lower part of the fixing sleeve for bottom sealing, and a sealing assembly is installed on the upper part for top sealing. The sealing assembly consists of a fixing ring, an elastic ring, and an upper sealing disc. When the temperature rises, the upper sealing disc expands, compressing the elastic ring and enhancing the seal between the upper and lower sealing rings, preventing sealing failure at high temperatures.

[0005] Furthermore, a connecting hole is provided at the center of the top of the cap body, and the convex cap is connected to the connecting hole. A vent hole is provided at the top of the cap body outside the convex cap. A connecting hole is provided at the center of the top of the cap body to connect the convex cap with the interior. At the same time, a vent hole is provided at the top to discharge the internal gas.

[0006] Furthermore, a reinforcing ring is fixed to the bottom end of the fixing sleeve, and the reinforcing ring is fixed to the inner wall of the cap body. A limiting ring is fixed to the lower part of the inner ring of the reinforcing ring. The bottom of the fixing sleeve is fixed to the inner wall of the cap body through the reinforcing ring to enhance the structural strength. A limiting ring is provided at the lower part of the inner ring of the reinforcing ring for positioning the battery steel shell.

[0007] Furthermore, a gas supply sleeve is vertically fixed in the center of the lower sealing disk. The bottom end of the gas supply sleeve is open and the top end is closed. The upper part of the periphery of the gas supply sleeve has exhaust holes arranged in a ring array. The gas supply sleeve is fixed in the center of the lower sealing disk. Its bottom is open and the top is closed. Exhaust holes are opened on the upper part of the side wall. When the internal gas pressure of the battery increases, the gas is discharged through the gas supply sleeve.

[0008] Furthermore, the sealing assembly also includes a sealing sleeve, which is vertically fixed in the center of the upper sealing disc. The air supply sleeve is movably connected inside the sealing sleeve and the exhaust hole is located inside the sealing sleeve. The sealing sleeve is fixed in the center of the upper sealing disc. The air supply sleeve can move up and down inside the sealing sleeve. The exhaust hole is located inside the sealing sleeve and is normally sealed. When the air pressure increases, it is exposed as the air supply sleeve rises, thus venting the air.

[0009] Furthermore, the sealing assembly also includes reinforcing rib one and reinforcing rib two. Two concentric annular reinforcing rib one is fixed at the top of the upper sealing disc, and two concentric reinforcing rib two is fixed at the bottom of the lower sealing disc. Reinforcing rib one and reinforcing rib two are staggered from a top view. Reinforcing rib one and reinforcing rib two are respectively provided at the top of the upper sealing disc and the bottom of the lower sealing disc. The two are staggered to enhance the strength of the sealing disc and prevent deformation.

[0010] Furthermore, a compression spring is fixed to the inner top of the convex cap, and a sealing pressure plate is fixed to the bottom of the compression spring. The bottom end of the sealing pressure plate abuts against the center of the top of the upper sealing plate. The convex cap is equipped with a compression spring and a sealing pressure plate. The sealing pressure plate abuts against the center of the top of the upper sealing plate. Under normal conditions, the compression spring causes the sealing pressure plate to press against the upper sealing plate to maintain a seal. When the internal air pressure rises, the air supply sleeve lifts the sealing pressure plate, compresses the compression spring, exposes the exhaust hole, and exhausts air. After the air pressure drops, the compression spring causes the sealing pressure plate to reset and reseal.

[0011] This utility model has the following beneficial effects: This invention solves the problem of sealing failure caused by thermal expansion of the internal seals of the power battery cap under high-temperature conditions by setting up a cap body and sealing components. The upper sealing plate expands after the temperature rises and actively presses against the elastic ring, making the elastic ring and the fixed ring more tightly pressed. The lower sealing plate and the gas supply sleeve also expand due to high temperature, squeezing the fixed sleeve and the sealing sleeve respectively. However, the reinforcing rib one and reinforcing rib two increase the radial strength of the upper sealing plate. This design ensures that the entire sealing system will not fail at high temperatures, but will instead form a tighter seal, that is, "using heat to control heat", turning the unfavorable thermal expansion factor into a favorable sealing enhancement factor.

[0012] This invention solves the problem of safe pressure relief and automatic resealing of a power battery cap when the internal pressure of the battery abnormally increases, by setting up a cap body, sealing components, and a convex cap. When the internal pressure of the battery increases, the gas pressure pushes the lower sealing plate and the connected gas supply sleeve upward. The gas supply sleeve lifts the sealing pressure plate and compresses the compression spring until the vent hole on its side passes the top of the sealing sleeve and enters the upper cavity of the cap. The gas is then safely discharged through the vent hole, achieving pressure relief. When the internal pressure drops, the elastic force of the compression spring pushes the sealing pressure plate downward, thereby causing the gas supply sleeve to move downward, so that the vent hole is submerged back into the sealing sleeve, restoring the sealing state. This process realizes a "pressure relief-automatic resetting" cycle, which not only ensures safety but also avoids permanent damage to the battery. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 A three-dimensional view of the structure of a power battery cap after being cut open to prevent high-temperature sealing failure; Figure 2 This is a three-dimensional view of the structure of the main body of the cap after it has been cut open. Figure 3 for Figure 2 Enlarged view of the structure at point A in the image; Figure 4 This is a three-dimensional view of the gas transmission jacket after it has been cut open. Figure 5 This is a three-dimensional view of the structure of the sealing component after it has been partially cut open. Figure 6 This is a three-dimensional view of the structure after the convex cap part has been cut open. Figure 7 This is a three-dimensional view of the assembly structure of a power battery cap to prevent high-temperature sealing failure.

[0015] Figure label: 1. Cap body; 101. Connecting hole; 102. Reinforcing ring; 103. Limiting ring; 104. Fixing sleeve; 105. Lower sealing plate; 106. Air supply sleeve; 1061. Exhaust hole; 107. Vent hole; 2. Sealing assembly; 201. Fixing ring; 202. Elastic ring; 203. Upper sealing plate; 204. Sealing sleeve; 205. Reinforcing rib one; 206. Reinforcing rib two; 3. Convex cap; 301. Compression spring; 302. Sealing pressure plate. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model. Specific Implementation Example 1

[0017] Please see Figure 1-5This utility model is a power battery cap to prevent high-temperature seal failure, including a cap body 1, a sealing component 2, and a convex cap 3. The convex cap 3 is fixed to the center of the top of the cap body 1. The cap body 1 is used for movable connection with the battery steel shell, sealing the top of the battery steel shell. The convex cap 3 is used for connection with the external electrodes of the battery. A fixing sleeve 104 is fixed to the lower part of the inner wall of the cap body 1. A lower sealing disc 105 is connected and disposed within the fixing sleeve 104. The lower sealing disc 105 is fixed at the lower edge of the inner wall of the fixing sleeve 104. During operation, the lower sealing disc 105 provides a lower seal within the cap body 1. A sealing component is fixed to the inner wall of the cap body 1 at the top of the fixing sleeve 104. The sealing component 2 seals the upper part of the cap body 1. The sealing component 2 includes a fixing ring 201, an elastic ring 202, and an upper sealing disc 203. The elastic ring 202 is fixed on the inner wall of the fixing ring 201, and the upper sealing disc 203 is fixed on the inner wall of the elastic ring 202. The upper sealing disc 203 is movably connected inside the fixing ring 201. The fixing ring 201 fixes the elastic ring 202 therein. When the battery temperature rises, the upper sealing disc 203 expands and presses against the elastic ring 202, so that the elastic ring 202 and the fixing ring 201 are pressed tightly. The movable connection between the fixing ring 201 and the upper sealing disc 203 reduces the deformation of the upper sealing disc 203.

[0018] Specifically, a connecting hole 101 is provided at the center of the top of the cap body 1, and the convex cap 3 is connected to the connecting hole 101. A vent hole 107 is provided at the top of the cap body 1 on the outside of the convex cap 3. The cap body 1 is connected to the convex cap 3 through the connecting hole 101, and the cap body 1 is ventilated through the vent hole 107.

[0019] Furthermore, a reinforcing ring 102 is fixed to the bottom end of the fixing sleeve 104. The reinforcing ring 102 is fixed to the inner wall of the cap body 1. A limiting ring 103 is fixed to the lower part of the inner ring of the reinforcing ring 102. The fixing sleeve 104 increases its strength through the reinforcing ring 102 and limits the position of the battery steel shell through the limiting ring 103.

[0020] Furthermore, a gas supply sleeve 106 is vertically fixed in the center of the lower sealing plate 105. The bottom end of the gas supply sleeve 106 is open and the top end is closed. The upper part of the periphery of the gas supply sleeve 106 has exhaust holes 1061 arranged in a ring. The bottom end of the gas supply sleeve 106 is connected to the inside of the battery steel shell. After the gas supply sleeve 106 extends out of the sealing sleeve 204, the exhaust holes 1061 are exposed, and the gas generated inside the battery steel shell is discharged to the upper part of the cap body 1.

[0021] Furthermore, the sealing assembly 2 also includes a sealing sleeve 204. The sealing sleeve 204 is vertically fixed in the center of the upper sealing disc 203. The air supply sleeve 106 is movably connected in the sealing sleeve 204 and the exhaust port 1061 is provided in the sealing sleeve 204. The sealing assembly 2 is movably connected to the air supply sleeve 106 through the sealing sleeve 204, and the air supply sleeve 106 is movably connected in the sealing sleeve 204.

[0022] Furthermore, the sealing assembly 2 also includes reinforcing rib 1 205 and reinforcing rib 206. Two concentric annular reinforcing ribs 1 205 are fixed to the top of the upper sealing disc 203, and two concentric reinforcing ribs 206 are fixed to the bottom of the lower sealing disc 105. The reinforcing ribs 1 205 and reinforcing rib 206 are staggered from each other when viewed from above. During operation, the reinforcing ribs 1 205 and reinforcing rib 206 increase the strength of the upper sealing disc 203.

[0023] The operation process of this embodiment is as follows: During operation, after the temperature of the cap body 1 rises, the lower sealing plate 105 expands at high temperature, compressing the fixed sleeve 104. At the same time, the air supply sleeve 106 heats up, compressing the sealing sleeve 204. Simultaneously, the temperature of the upper sealing plate 203 rises, the upper sealing plate 203 expands, and compresses the elastic ring 202, so that the elastic ring 202 compresses the fixed ring 201. This ensures that the internal seal of the cap body 1 will not fail under high temperature, thus guaranteeing stable operation. Specific Implementation Example 2

[0024] Please see Figure 1-6 Based on the first specific embodiment, a compression spring 301 is fixed to the inner top of the convex cap 3, and a sealing pressure plate 302 is fixed to the bottom of the compression spring 301. The bottom end of the sealing pressure plate 302 abuts against the center of the top of the upper sealing plate 203. The compression spring 301 inside the convex cap 3 elastically presses the sealing pressure plate 302 downward. After the sealing pressure plate 302 presses and tightens against the center of the top of the upper sealing plate 203, the top of the air supply sleeve 106 is limited and further seals the gap between the top of the air supply sleeve 106 and the sealing sleeve 204.

[0025] The operation process of this embodiment is as follows: During operation, after the battery steel shell and the cap body 1 are installed and welded together, when gas is generated inside the battery steel shell and the pressure increases, the gas causes the lower sealing plate 105 to bulge upward and deform, causing the gas supply sleeve 106 to rise. It rises in the sealing sleeve 204 inside the upper sealing plate 203, pushing the sealing pressure plate 302 to rise. After being pushed by the sealing pressure plate 302, the gas supply sleeve 106 rises and extends out of the top of the sealing sleeve 204, and the compression spring 301 is compressed until the exhaust hole 1061 on the periphery of the gas supply sleeve 106 extends out of the sealing sleeve 204. The gas generated inside the battery steel shell enters the cap body 1 above the upper sealing plate 203 and is discharged through the vent hole 107 at the top of the cap body 1. After the pressure inside the battery steel shell decreases, the pressure of the compression spring 301 pushes the sealing pressure plate 302 down, causing the gas supply sleeve 106 to down, so that the exhaust hole 1061 returns to the sealing sleeve 204 inside the upper sealing plate 203, completing the reset.

[0026] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," 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 present 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.

[0027] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A power battery cap for preventing high-temperature sealing failure, comprising a cap body (1), a sealing assembly (2), and a convex cap (3), characterized in that: A convex cap (3) is fixed at the center of the top of the cap body (1). A fixing sleeve (104) is fixed at the lower part of the inner wall of the cap body (1). A lower sealing plate (105) is fixed at the edge of the lower part of the inner wall of the fixing sleeve (104). A sealing component (2) is fixed on the inner wall of the cap body (1) at the top of the fixing sleeve (104). The sealing component (2) includes a fixing ring (201), an elastic ring (202) and an upper sealing plate (203). An elastic ring (202) is fixed on the inner wall of the fixing ring (201). An upper sealing plate (203) is fixed on the inner wall of the elastic ring (202). The upper sealing plate (203) is movably connected inside the fixing ring (201).

2. A power battery cap for preventing high-temperature sealing failure according to claim 1, characterized in that: The cap body (1) has a connecting hole (101) at the center of its top end. The convex cap (3) is connected to the connecting hole (101). The cap body (1) on the outside of the convex cap (3) has a vent hole (107) at its top end.

3. A power battery cap for preventing high-temperature sealing failure according to claim 1, characterized in that: A reinforcing ring (102) is fixed at the bottom of the fixed sleeve (104). The reinforcing ring (102) is fixed on the inner wall of the cap body (1). A limit ring (103) is fixed at the lower part of the inner ring of the reinforcing ring (102).

4. A power battery cap for preventing high-temperature sealing failure according to claim 1, characterized in that: An air supply sleeve (106) is vertically fixed in the center of the lower sealing disc (105). The bottom opening of the air supply sleeve (106) is closed at the top. The upper part of the air supply sleeve (106) is provided with exhaust holes (1061) in a ring array on the periphery.

5. A power battery cap for preventing high-temperature sealing failure according to claim 4, characterized in that: The sealing assembly (2) also includes a sealing sleeve (204), in which the sealing sleeve (204) is vertically fixed in the center of the upper sealing disc (203), and the air supply sleeve (106) is movably connected in the sealing sleeve (204) and the exhaust hole (1061) is located in the sealing sleeve (204).

6. A power battery cap for preventing high-temperature sealing failure according to claim 1, characterized in that: The sealing assembly (2) further includes reinforcing rib one (205) and reinforcing rib two (206). The top of the upper sealing disc (203) is fixed with two concentric annular reinforcing rib one (205), and the bottom of the lower sealing disc (105) is fixed with two concentric reinforcing rib two (206). The reinforcing rib one (205) and reinforcing rib two (206) are staggered from each other when viewed from above.

7. A power battery cap for preventing high-temperature sealing failure according to claim 1, characterized in that: A compression spring (301) is fixed to the inner top of the convex cap (3), and a sealing pressure plate (302) is fixed to the bottom of the compression spring (301). The bottom end of the sealing pressure plate (302) abuts against the center of the top of the upper sealing plate (203).

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