Quantitative diagnosis method of battery internal short circuit based on peak height of incremental capacity curve

Abstract

The present invention relates to a battery internal short-circuit quantitative diagnosis method based on the peak height of the incremental capacity curve, comprising the following steps: 1) establishing the incremental capacity curves of the battery at different aging stages and different internal short-circuit resistance values ​​as the benchmark incremental capacity 2) Determine the relationship between the peak height of the characteristic peak in the benchmark incremental capacity curve of different aging stages and the battery internal short circuit, and obtain the battery internal short circuit resistance estimation model at different aging stages; 3) Obtain the incremental capacity of the battery to be tested online 4) Obtain the peak height of the characteristic peak in the incremental capacity curve of the battery to be tested, and compare it with the peak height of the characteristic peak in the reference incremental capacity curve of the corresponding aging stage to determine whether an internal short circuit occurs; 5) Calculate the battery short-circuit resistance of the battery to be tested according to the battery short-circuit resistance estimation model corresponding to the aging stage. Compared with the prior art, the present invention has the advantages of simple implementation, short diagnosis time, high diagnosis accuracy and the like.

Description

technical field [0001] The invention relates to the technical field of energy storage batteries, in particular to a method for quantitatively diagnosing short circuits in batteries based on the peak height of incremental capacity curves. Background technique [0002] In recent years, lithium batteries are gradually becoming the main power source of electric vehicles due to their high specific energy (power) density, long life, safety and reliability. However, lithium-ion batteries also have certain potential problems. One of the biggest potential problems is thermal runaway, because when a lithium-ion battery suffers from thermal runaway, it will heat up rapidly within a few minutes and have an exothermic chain reaction, which will eventually cause the battery to smoke, Burn or even explode. [0003] The existing mainstream view is that thermal runaway is caused by an internal short circuit in the battery. In order to improve the safety of the battery, many internal short-...

AI Technical Summary

Problems solved by technology

According to the difference between the model parameters of the short-circuited battery and the normal battery to diagnose whether the battery has an internal short circuit, but this method can only detect the presence of an internal short circuit and cannot quantitatively diagnose the internal short circuit

3) Power loss method

Comparing the AC impedance spectrum of the battery to be tested with the AC impedance spectrum of the normal battery can identify whether the battery has an internal short circuit, but this method is relatively expensive and technically difficult to implement, and at the same time cannot quantitatively calculate the internal short circuit resistance

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