Cylindrical lithium ion battery

Abstract

The invention discloses a lithium ion battery, which comprises a battery shell, a pole sheet group accommodated inside the battery shell, an electrolyte filled in the battery shell, and a battery cover cap forming a sealing group connection on the battery shell, wherein a top cover folds inward along the edge of an explosion-proof sheet to form the coated explosion-proof sheet from three directions, and the end part of the top cover is provided with concave-convex sealing steps, such that effects of rigidity increasing, avoidance of the explosion-proof sheet deformation due to exerted force, and sealing increasing in the sealing port are provided. In the prior art, due to deformation or leakage, the pressure relief value of the explosion-proof sheet becomes large or the explosion-proof sheet does not burst so as to cause occurrence of combustion, explosion, and other safety problems. According to the present invention, problems in the prior art are prevented, stability, sealing and safety of the cylindrical lithium ion battery are improved, and capacity of the battery is increased.

Description

technical field [0001] The invention relates to a lithium ion battery, in particular to a cylindrical lithium ion battery with good safety performance. Background technique [0002] With the development of modern society, mobile devices such as camcorders, notebook computers, portable DVDs and digital cameras have been used more and more widely. Cylindrical lithium-ion batteries, as a green and environmentally friendly battery, have the advantages of high energy density, high operating voltage and long service life, so they are more and more widely used in various mobile devices. [0003] Cylindrical lithium-ion batteries generally include a pole piece group with a wound structure. The pole piece group is wound from a positive pole piece, a negative pole piece, and a separator spaced between the positive pole piece and the negative pole piece. The pole piece with a wound structure Assembled into the battery case and filled with electrolyte, then sealed by the battery cap. ...

AI Technical Summary

Problems solved by technology

The support platform formed by the rolling groove is short and not horizontal. During the crimping and sealing process, the cap body moves downward due to the downward pressure of the edge of the shell mouth.

The aluminum explosion-proof plate in the cap body is deformed, and the common problems caused by the deformation are as follows: 1. The power failure and pressure relief value become larger and cannot be acted in time, and the product entering the market is prone to safety hazards

2. The compression amount of the apron fluctuates, resulting in poor sealing performance. 3. The gap between components changes, resulting in resistance fluctuations

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