Cap assembly

Abstract

The utility model relates to a cap assembly, which is characterized in that an explosion-proof sheet is arranged on the inner bottom of a sealing ring, a cap sheet is crimped on the explosion-proof sheet, the explosion-proof sheet upwards wraps the cap sheet and then is folded to form an explosion-proof sheet crimping edge for press fitting of a cap sheet skirt edge, an outer ring of the sealing ring wraps the explosion-proof sheet, and a sealing ring crimping edge for press fitting of the explosion-proof sheet crimping edge is folded behind the cap sheet. The reinforcing protrusions are located between every two adjacent cap air holes in the circumferential direction and arranged in the radial direction of the circumference of the cap piece, pressure relief through holes are formed in the portions, between every two adjacent reinforcing protrusions, of the skirt edge of the cap piece, and a circle of pressure relief nicks with the diameter smaller than that of the pressure relief through holes are formed in the portion, below the corresponding pressure relief through holes, of the anti-explosion piece. The pressure relief nick is of an incomplete circumferential structure which faces the inner side and is free of nick. The reinforcing bulges are arranged on the skirt of the cap piece in a staggered manner, the cap air holes and the pressure relief through holes, so that the structural strength of the skirt of the cap piece is improved, the pressure relief nick position of the explosion-proof piece is ensured to be effectively crimped, the pressure relief nick is prevented from being broken to relieve pressure when the pressed bulges cannot be subjected to critical pressure, and the safety performance of the battery is effectively improved.

Description

Technical Field

[0001] The utility model relates to a battery cap assembly. Background Art

[0002] With the development of battery technology, the requirements for battery performance and explosion-proof safety have been greatly improved. In the traditional cap structure, a pressure relief notch is opened in a non-centered circle around the explosion-proof sheet, and there is a safety hazard that the explosion-proof sheet within the notch bursts and splashes during pressure relief; moreover, the non-centered skirt of the cap corresponding to the explosion-proof sheet is also under pressure. For the single-board skirt structure, there is a hidden danger of convex deformation under pressure, resulting in unstable crimping of the explosion-proof sheet below. When the critical pressure is reached, the explosion-proof sheet bulges upward with it, and the explosion-proof sheet cannot relieve pressure through the pressure relief notch in time, affecting the explosion-proof safety performance. Summary of the Invention

[0003] The utility model provides a battery cap assembly with a simple and stable structure, without deformation and safety hazards.

[0004] The technical solution adopted by the utility model is: a cap assembly, including a cap sheet, an explosion-proof sheet and a sealing ring. The explosion-proof sheet is installed on the inner bottom of the sealing ring, and the cap sheet is crimped on the explosion-proof sheet. After the explosion-proof sheet wraps the cap sheet upward, an explosion-proof sheet crimping edge is folded out and pressed on the skirt of the cap sheet. The outer ring of the sealing ring wraps the explosion-proof sheet and the cap sheet, and then a sealing ring crimping edge is folded out and pressed on the explosion-proof sheet crimping edge. There is a convex cap head structure in the middle of the cap sheet, and a plurality of cap air holes are arranged in a circle around the periphery of the cap head structure. It is characterized in that: a plurality of reinforcing protrusions are arranged in a circle around the skirt of the cap sheet, each reinforcing protrusion is located in the middle of the circumferential direction between two adjacent cap air holes and is arranged along the radial direction of the circumference of the cap sheet. Pressure relief through holes are arranged between two adjacent reinforcing protrusions on the skirt of the cap sheet. A pressure relief notch with a diameter smaller than the pressure relief through hole is arranged on the explosion-proof sheet corresponding to the lower part of the pressure relief through hole. The pressure relief notch is an incomplete circumferential structure without a notch towards the inside.

[0005] The sealing ring is made of high-temperature polyethylene propylene.

[0006] The cap head of the cap sheet is nickel-plated.

[0007] The nickel-plating thickness is 4 - 8 μm.

[0008] The cap sheet and the explosion-proof sheet are welded by more than 4 solder joints around the circumference.

[0009] Lithium battery sealant is applied to the inner bottom of the sealing ring and the inner wall of the outer ring of the sealing ring.

[0010] The upper plane of the cap sheet corresponding to the crimping edge of the explosion-proof sheet is a mesh convex rib or a mesh concave groove.

[0011] An inner liquid injection hole is arranged at the center of the explosion-proof sheet, an outer liquid injection hole corresponding to the inner liquid injection hole is arranged on the cap head, and a hole sealing plate is arranged on the outer liquid injection hole.

[0012] The utility model effectively improves the structural strength of the skirt of the cap piece by arranging reinforcing protrusions at the cap gas holes and the pressure relief through holes in a staggered manner on the skirt of the cap piece, ensures the effective and stable pressing connection of the position of the pressure relief notch of the explosion-proof piece, avoids the pressure relief notch from breaking and relieving pressure when the pressure receiving protrusion cannot reach the critical pressure, effectively improves the battery safety performance. At the same time, the pressure relief notch is not a complete circumference, which can prevent the outward splashing when the pressure relief breaks, and improves the use safety. Brief Description of the Drawings

[0013] Figure 1 It is a schematic structural view of the first embodiment of the utility model;

[0014] Figure 2 is Figure 1 Top view;

[0015] Figure 3 It is a schematic structural view of the second embodiment of the utility model.

[0016] In the figure: cap piece 1, cap head 2, cap gas hole 3, skirt 4, reinforcing protrusion 5, pressure relief through hole 6, explosion-proof piece 7, pressure relief notch 8, explosion-proof piece pressing edge 9, sealing ring 10, sealing ring pressing edge 11, internal liquid injection hole 12, external liquid injection hole 13, hole sealing plate 14. Detailed Description of the Preferred Embodiments

[0017] The following is further described in conjunction with the drawings and embodiments.

[0018] Figure 1 、 2 As shown in the first embodiment, a cap assembly includes a cap piece 1, an explosion-proof piece 7 and a sealing ring 10. The explosion-proof piece 7 is installed on the inner bottom of the sealing ring 10, the cap piece 1 is press-fitted on the explosion-proof piece 7. After the explosion-proof piece 7 wraps the cap piece 1 upward and is turned over to form an explosion-proof piece pressing edge 8, it is press-fitted on the skirt 4 of the cap piece. The outer ring of the sealing ring 10 wraps the explosion-proof piece 7 and the cap piece 1 and is turned over to form a sealing ring pressing edge 11, which is press-fitted on the explosion-proof piece pressing edge 9. The cap piece 1 has a convex cap head 2 structure in the middle. A plurality of cap gas holes 3 are arranged in a circle on the outer periphery of the cap head 2 structure. A plurality of reinforcing protrusions 5 are arranged in a circle around the circumference on the skirt 4 of the cap piece. Each reinforcing protrusion is located in the middle of the circumferential direction of two adjacent cap gas holes and is arranged along the radial direction of the cap piece circumference. A pressure relief through hole 6 is arranged on the skirt 4 of the cap piece between two adjacent reinforcing protrusions. An incomplete circumferential structure with no notch on the inner side is arranged on the explosion-proof piece 7 below the corresponding pressure relief through hole 6, and the pressure relief notch is a non-complete circumferential structure with no notch on the inner side.

[0019] Figure 3 As shown in the second embodiment, compared with the first embodiment, an internal liquid injection hole 12 is arranged in the center of the explosion-proof piece 7, an external liquid injection hole 13 corresponding to the internal liquid injection hole is arranged on the cap head 2, and a hole sealing plate 14 is arranged on the external liquid injection hole for use in post-liquid injection.

[0020] Based on the above embodiments, the sealing ring can be made of high-temperature polyethylene propylene.

[0021] Based on the above embodiments, the cap head of the cap piece is nickel-plated, and the nickel-plating thickness is 4 - 8 μm.

[0022] Based on the above embodiments, the cap piece and the explosion-proof piece are welded with more than 4 solder joints around the circumference.

[0023] Based on the above embodiments, a gasket can also be arranged under the cap piece to press-fit the explosion-proof piece, and a gasket through-hole corresponding to the pressure relief ring is arranged in the center of the gasket.

[0024] Based on the above embodiments, a lithium battery sealant can also be applied to the inner bottom of the sealing ring and the inner wall of the outer circle of the sealing ring.

[0025] Based on the above embodiments, the upper plane of the cap piece corresponding to the crimping edge of the explosion-proof piece can also be a mesh convex rib or a mesh concave groove.

Claims

1. A cap assembly, comprising a cap sheet, an explosion-proof sheet and a sealing ring, wherein the explosion-proof sheet is mounted on the inner bottom of the sealing ring, the cap sheet is crimped onto the explosion-proof sheet, the explosion-proof sheet is upwardly wrapped around the cap sheet and then folded out of the crimping edge of the explosion-proof sheet and then pressed onto the cap sheet skirt, the outer ring of the sealing ring wraps around the explosion-proof sheet, the cap sheet is folded out of the crimping edge of the sealing ring and then pressed onto the crimping edge of the explosion-proof sheet, a cap head structure is raised in the middle of the cap sheet, and a circle of multiple cap air holes are arranged on the periphery of the cap head structure, characterized in that: A circle of multiple reinforcing protrusions are arranged around the circumference of the skirt of the cap piece, each reinforcing protrusion is located in the middle of the circumferential direction of the two cap air holes and is arranged radially along the circumference of the cap piece, and a pressure relief through hole is arranged between the two reinforcing protrusions on the skirt of the cap piece, and a circle of pressure relief notches with a diameter smaller than the pressure relief through hole is arranged on the explosion-proof sheet below the corresponding pressure relief through hole, and the pressure relief notches are incomplete circular structures without notches facing inward.

2. A cap assembly according to claim 1, characterized in that: The sealing ring is made of high temperature polyethylene propylene.

3. A cap assembly according to claim 1, characterized in that: The cap head of the cap piece is nickel plated.

4. A cap assembly according to claim 3, characterized in that: The nickel plating thickness is 4-8 μm.

5. The cap assembly according to claim 1, characterized in that: The cap plate and the explosion-proof plate are welded at more than four welding points around the circumference.

6. The cap assembly according to claim 1, characterized in that: The inner bottom of the sealing ring is coated with lithium battery sealant, and the inner wall of the outer ring of the sealing ring is coated with lithium battery sealant.

7. The cap assembly according to claim 1, characterized in that: The upper plane of the cap sheet corresponding to the crimping edge of the explosion-proof sheet is a mesh-shaped convex ridge or a mesh-shaped concave pattern.

8. The cap assembly according to claim 1, characterized in that: The explosion-proof plate is provided with an inner injection hole at the center, the cap head is provided with an outer injection hole corresponding to the inner injection hole, and a hole sealing plate is provided at the outer injection hole.

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