A kind of safe anti-overcharge cover plate of ternary lithium battery

Abstract

The invention provides a safety overcharge prevention cover plate for a ternary lithium battery, comprising a cover main body, a bottom insulating plate, and a positive pole and a negative pole respectively fixed on the upper end surface of the cover main body, the positive pole and the cover main body Conduction, an insulating pad is provided between the negative pole and the main body of the cover plate; the bottom end of the negative pole is connected with a temperature sensing device for sensing the internal temperature of the lithium battery, and the bottom of the temperature sensing device is equipped with a liquid conductive medium. When the internal temperature of the battery is too high, the liquid conductive medium expands and rises to its top, and conducts the negative electrode column with the main body of the cover plate to form an external short circuit. When the battery overcharge temperature rises, the liquid conductive medium expands and the temperature sensing device becomes a conductor, and then the negative pole is connected to the main body of the cover plate, forming an external short circuit, preventing thermal runaway during overcharging, and ensuring battery overcharging safety.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a safety overcharge prevention cover plate for a ternary lithium battery. Background technique [0002] With the development of ternary material lithium batteries and the improvement of battery energy density, a single measure of adding anti-overcharge electrolyte additives or a simple cover plate structure can no longer meet the needs of ternary battery safety performance and cycle life. In view of the requirements of the overcharge test in the safety performance test of the ternary battery, the problem of improving the safety of the overcharge test on the structure of the ternary battery needs to be solved urgently. At present, the cover plate of ordinary lithium battery basically has no anti-overcharge structure. Most of the anti-overcharge methods of the battery are to add electrolyte additives. The anti-overcharge electrolyte additives used will generate gas wh...

AI Technical Summary

Problems solved by technology

At present, the cover plate of ordinary lithium battery basically has no anti-overcharge structure. Most of the anti-overcharge methods of the battery are to add electrolyte additives. The anti-overcharge electrolyte additives used will generate gas when the battery is overcharged, causing the battery to bulge. Affect battery pack

At the same time, the anti-overcharge electrolyte additive has certain side effects on the cycle performance of the battery and affects the performance of the electrical performance.

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