An explosion-proof cap for lithium batteries with automatic reset function

Abstract

This utility model provides an automatically resetting explosion-proof cap for lithium batteries, relating to the field of battery technology. It includes a lower cap with a flow groove inside. A rubber ring is positioned around the perimeter of the top surface of the flow groove, with the bottom of the rubber ring positioned at the top of the lower cap. A torsion spring and a rotating block work together to automatically open the upper cap to release pressure when the internal pressure of the battery is abnormal, and automatically reset and seal after the pressure returns to normal. A guide rod provides a stable axis of rotation for the rotating block, while a fixed block provides rigid support for the entire mechanism. Specifically, a sponge inside the rotating block absorbs lubricating oil, making the rotation of the rotating block smoother on the guide rod surface and effectively reducing frictional resistance. The preload of the torsion spring is precisely designed to ensure reliable sealing under normal pressure and to trigger sensitively under overpressure, thus achieving automatic pressure relief and reset functions without external intervention, significantly improving the safety and lifespan of the lithium battery.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an explosion-proof cap for lithium batteries that can be automatically reset. Background Technology

[0002] According to a lithium battery explosion-proof cap disclosed in Chinese Publication No. CN211480098U, it comprises, from top to bottom, a top cover, an explosion-proof sheet, a perforated plate, and an insulating ring. The top cover and the explosion-proof sheet are laser-welded together, and the explosion-proof sheet is welded to the perforated plate. The insulating ring is integrally equipped with a sealing ring. The integral sealing ring eliminates the need for a separate sealing ring, reducing assembly steps, improving process efficiency, reducing material usage, and lowering the overall amount of adhesive used.

[0003] However, the aforementioned devices have the following problems: when the internal pressure of the battery rises abnormally, it is not easy to release the pressure quickly and in a timely manner. This causes the accumulated high-pressure gas to cause excessive stress on the battery casing, which may eventually lead to serious safety accidents such as battery expansion, rupture, or even explosion. Traditional explosion-proof structures often have problems such as delayed response and poor pressure release, making it difficult to release internal pressure in a timely manner. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing an automatically resettable explosion-proof cap for lithium batteries.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a lower cap is provided, the lower cap has a flow groove inside, a rubber ring is provided around the top surface of the flow groove, the bottom of the rubber ring is provided at the top of the lower cap, an installation groove is provided on the outer side of the lower cap, and a fixing block is provided inside the installation groove.

[0006] Preferably, both ends of the fixed block are provided with rotating grooves, and guide rods are provided inside the two sets of rotating grooves.

[0007] Preferably, a rotating block is provided on the surface of the guide rod, and a torsion spring is provided in the middle of the surface of the guide rod.

[0008] Preferably, the bottom of the torsion spring is fixedly connected to the inner bottom of the fixed block, and the top of the torsion spring is fixedly connected to the inner top of the rotating block.

[0009] Preferably, one end of the rotating block is provided with two sets of through grooves, and the interior of each set of through grooves is provided with a sponge.

[0010] Preferably, the top of the rotating block is fixedly connected to an upper cap, and the upper cap has a buffer cavity inside.

[0011] Preferably, a reinforcing rod is provided at the top of the buffer cavity, the bottom of the upper cap is attached to the top of the lower cap, and the surface of the rubber ring is disposed inside the buffer cavity.

[0012] Beneficial effects

[0013] In this invention, the torsion spring and rotating block work together to automatically open the top cap to release pressure when the internal pressure of the battery is abnormal, and automatically reset the seal after the pressure returns to normal. The guide rod provides a stable axis of rotation for the rotating block, while the fixed block provides rigid support for the entire mechanism. In particular, the sponge inside the rotating block can absorb lubricating oil, making the rotating block rotate more smoothly on the surface of the guide rod and effectively reducing frictional resistance. The preload of the torsion spring is precisely designed to ensure reliable sealing under normal pressure and to trigger the action sensitively when overpressure occurs, thus realizing automatic pressure relief and reset functions without external intervention, significantly improving the safety and service life of lithium batteries.

[0014] In this invention, the design of the buffer cavity effectively absorbs and disperses the impact of high-pressure gas suddenly released from inside the battery, preventing the explosion-proof cap from being damaged by excessive stress. The reinforcing rod supports the top of the buffer cavity, maintaining the overall strength of the upper cap and thus enhancing the durability of the cap structure. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall appearance of the present utility model;

[0016] Figure 2 This is an internal sectional view of the present invention;

[0017] Figure 3 This is a structural diagram of the flow channel, mounting groove, and rubber ring of this utility model;

[0018] Figure 4 This is a structural diagram of the fixing block, guide rod, torsion spring, and rotating block of this utility model.

[0019] Legend:

[0020] 1. Lower cap; 2. Flow groove; 3. Rubber ring; 4. Mounting groove; 5. Fixing block; 6. Guide rod; 7. Rotating block; 8. Torsion spring; 9. Sponge body; 10. Upper cap; 11. Buffer cavity; 12. Reinforcing rod. Detailed Implementation

[0021] To make the technical means, creative features, and achieved objectives and effects of this utility model easier to understand, the present utility model is further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are merely preferred embodiments of this utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments described in the implementation plan without creative effort are all within the protection scope of this utility model.

[0022] The specific embodiments of this utility model are described below with reference to the accompanying drawings. Specific Implementation Example 1:

[0024] Reference Figure 1-4 An automatically resetting explosion-proof cap for lithium batteries includes a lower cap 1. The lower cap 1 has a circular flow groove 2 inside, through which high-pressure gas generated by the lithium battery flows. A rubber ring 3 is provided around the top periphery of the flow groove 2, with the bottom of the rubber ring 3 positioned at the top of the lower cap 1. An installation groove 4 is provided on the outer side of the lower cap 1, and a fixing block 5 is provided inside the installation groove 4. Both ends of the fixing block 5 have rotating grooves, and a guide rod 6 is provided inside both rotating grooves. The diameter of the guide rod 6 must match the rotating grooves of the fixing block 5. A rotating block 7 is provided on the surface of the guide rod 6, and a torsion spring 8 is provided in the middle of the surface of the guide rod 6. The bottom of the torsion spring 8 is fixedly connected to the inner bottom of the fixing block 5, and the top of the torsion spring 8 is fixedly connected to the inner top of the rotating block 7. All 8 are connected to the rotating block 7 and the fixed block 5 by welding. One end of the rotating block 7 has two sets of through slots. The inside of each set of through slots is provided with a sponge body 9. The sponge body 9 is made of sponge material with good adsorption performance and corrosion resistance. It is cut into a shape and size that matches the through slots of the rotating block 7 and fixed inside the through slots. The top of the rotating block 7 is fixedly connected to the top of the top cap 10. The inside of the top cap 10 is provided with a buffer cavity 11. The top of the buffer cavity 11 is provided with a reinforcing rod 12. The reinforcing rod 12 can effectively enhance the structural strength of the top cap 10. The bottom of the top cap 10 is attached to the top of the bottom cap 1. The surface of the rubber ring 3 is set inside the buffer cavity 11. The size and shape of the buffer cavity 11 must meet the installation requirements of the rubber ring 3 and the reinforcing rod 12.

[0025] Mounting holes that mate with guide rods 6 are machined on rotating block 7 to ensure that rotating block 7 can rotate flexibly on guide rods 6. The interior of mounting holes and through grooves are interconnected to ensure that sponge 9, which absorbs lubricating oil, can lubricate the connection between rotating block 7 and guide rods 6, making the top cap 10 rotate more smoothly. Workers can periodically drip lubricating oil onto sponge 9.

[0026] Both the lower cap 1 and the upper cap 10 are made of high-strength, corrosion-resistant metal materials. Specific Implementation Example 2:

[0028] An automatically resettable explosion-proof cap for lithium batteries, further based on the basic structure in Specific Embodiment 1, operates as follows: Under normal operating conditions, the upper cap 10 and lower cap 1 are tightly fitted together, with the rubber ring 3 providing a good seal to prevent gas leakage from the lithium battery. When the internal pressure of the lithium battery increases due to overcharging, over-discharging, or other abnormal conditions, gas enters through the flow groove 2 of the lower cap 1. The gas pressure acts on the rotating block 7, overcoming the torque of the torsion spring 8, causing the rotating block 7 to rotate around the guide rod 6, thereby rotating and opening the upper cap 10. The gas is then discharged through the opening, achieving the explosion-proof function. When the internal pressure of the lithium battery decreases, the rotating block 7 automatically resets under the action of the torsion spring 8, causing the upper cap 10 to re-fit tightly with the lower cap 1, restoring the sealing state. The reinforcing rod 12 enhances the structural strength of the upper cap 10 throughout the process, ensuring that the upper cap 10 does not deform or become damaged during opening and closing, thus improving the reliability and service life of the lithium battery explosion-proof cap.

[0029] In summary:

[0030] The torsion spring 8, in conjunction with the rotating block 7, automatically opens the top cap 10 to release pressure when the internal pressure of the battery is abnormal, and automatically resets the seal after the pressure returns to normal. The guide rod 6 provides a stable axis of rotation for the rotating block 7, while the fixing block 5 provides rigid support for the entire mechanism. Specifically, the sponge 9 inside the rotating block 7 absorbs lubricating oil, making the rotation of the rotating block 7 smoother on the surface of the guide rod 6 and effectively reducing frictional resistance. The preload of the torsion spring 8 is precisely designed to ensure reliable sealing under normal pressure and to trigger sensitively under overpressure, thus achieving automatic pressure release and reset without external intervention, significantly improving the safety and lifespan of the lithium battery.

[0031] The design of the buffer cavity 11 can effectively absorb and disperse the impact of high-pressure gas suddenly released inside the battery, preventing the explosion-proof cap from being damaged by excessive stress. The reinforcing rod 12 supports the top of the buffer cavity 11, which maintains the overall strength of the upper cap 10 and thus enhances the durability of the cap structure.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. An auto-resettable lithium battery explosion vented cap, comprising a lower cap (1), characterized in that: The lower cap (1) has a flow groove (2) inside. A rubber ring (3) is provided around the top surface of the flow groove (2). The bottom of the rubber ring (3) is located at the top of the lower cap (1). An installation groove (4) is provided on the outside of the lower cap (1). A fixing block (5) is provided inside the installation groove (4). A rotating groove is provided at both ends of the fixing block (5). A guide rod (6) is provided inside both sets of rotating grooves. A rotating block (7) is provided on the surface of the guide rod (6). A torsion spring (8) is provided in the middle of the surface of the guide rod (6). The bottom of the torsion spring (8) is fixedly connected to the inner bottom of the fixing block (5). The top of the torsion spring (8) is fixedly connected to the inner top of the rotating block (7).

2. The self-resetting explosion-proof cap for lithium batteries according to claim 1, characterized in that: Two sets of through slots are provided at one end of the rotating block (7), and a sponge (9) is provided inside the two sets of through slots.

3. The self-resetting explosion-proof cap for lithium batteries according to claim 1, characterized in that: The top of the rotating block (7) is fixedly connected to an upper cap (10), and a buffer cavity (11) is opened inside the upper cap (10).

4. The self-resetting explosion-proof cap for a lithium battery according to claim 3, characterized in that: A reinforcing rod (12) is provided at the top of the inner cavity (11).

5. The self-resetting explosion-proof cap for a lithium battery according to claim 3, characterized in that: The bottom of the upper cap (10) is attached to the top of the lower cap (1).

6. The self-resetting explosion-proof cap for a lithium battery according to claim 3, characterized in that: The surface of the rubber ring (3) is disposed inside the buffer cavity (11).

7. The self-resetting explosion-proof cap for a lithium battery according to claim 1, characterized in that: The flow channel (2) is circular.

Images