Lithium ion power battery cap and welding method thereof

Abstract

The invention relates to a lithium ion power battery cap and a welding method thereof, which belong to the technical field of lithium ion batteries. The lithium ion power battery cap comprises a top cover, an anti-explosion membrane, a gasket and a polar plate, wherein the top cover, the anti-explosion membrane, the gasket and the polar plate are sequentially combined. The invention is characterized in that a groove is formed on the top cover or on the anti-explosion membrane, brazing materials of the top cover and the anti-explosion membrane are arranged in the groove, and the top cover and the anti-explosion membrane are in a connection structure in a brazing mode. The welding method of the lithium ion power battery cap has the following steps: sequentially assembling the top cover, the anti-explosion membrane, the gasket and the polar plate; and additionally adding a sealing ring. The invention is characterized in that when the top cover and the anti-explosion membrane are processed, firstly, the groove is manufactured on the top cover and the anti-explosion membrane, the brazing materials are placed in the groove of the top cover or the anti-explosion membrane, and the top cover and the anti-explosion membrane are welded into an integral structure through brazing. The invention has the advantages of novel technology, convenient processing, firm contact, small contact resistance, no resistance drift, high safety grade, long service life of the battery, wide application range and the like.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, in particular to a lithium-ion power battery cap and a welding method thereof. Background technique [0002] At present, lithium-ion batteries have the characteristics of small size, light weight, strong power, no memory, and environmental protection, and are widely used in industrial production and daily life. The existing lithium-ion power battery cap includes a top cover, an explosion-proof diaphragm, a gasket and a pole plate, and the top cover is combined with the explosion-proof diaphragm, the gasket and the pole plate in sequence. The contact between the top cover of the existing cap and the explosion-proof diaphragm is not firm, or the welding method of adding a transition layer in the middle is used for processing, which has technical problems such as complex process, high production cost, and low production efficiency. Moreover, it affects the resistance increase of the ba...

AI Technical Summary

Problems solved by technology

The contact between the top cover of the existing cap and the explosion-proof diaphragm is not firm, or the welding method of adding a transition layer in the middle is used for processing, which has technical problems such as complex process, high production cost, and low production efficiency. Moreover, it affects the resistance increase of the battery. Large, causing resistance drift, directly reducing the performance level of the battery, posing safety hazards, and even causing major accidents, etc.

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