Relaxation voltage characteristic-based battery internal short circuit diagnosis method

Abstract

The invention relates to a relaxation voltage characteristic-based battery internal short circuit diagnosis method, which comprises the following steps of: 1) obtaining a relaxation voltage curve of each battery monomer in a battery after unloading current under the same battery condition; (2) carrying out feature extraction on the relaxation voltage curve of each single battery to obtain corresponding curve features, and (3) judging whether the single batteries have internal short circuits or not according to the curve features to complete diagnosis. Compared with the prior art, the method has the advantages of short detection time, high accuracy and the like.

Description

technical field [0001] The invention relates to the field of battery fault diagnosis, in particular to a method for diagnosing a short circuit in a battery based on relaxation voltage characteristics. Background technique [0002] Lithium-ion batteries are widely used in vehicles, electronic products, and energy storage power stations due to their advantages such as high specific energy density and long cycle life. However, safety accidents of lithium-ion batteries occur from time to time. There are many internal short circuits in lithium-ion batteries, including manufacturing defects, mechanical abuse, electrical abuse, and thermal abuse. Internal short circuits may occur at any time during the entire life cycle of the battery. Internal short circuits can easily cause thermal runaway and cause serious safety accidents. Therefore, , The internal short circuit needs to be diagnosed in time and give an early warning, so as to ensure the safety of life and property. [0003] I...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, a threshold-based method is generally used to detect whether an internal short circuit occurs, that is, to determine whether an internal short circuit occurs by detecting whether the voltage change difference, current change difference, and temperature change difference exceed a set threshold, but now Some internal short circuit detection methods take a long time to detect, are susceptible to external interference, and the detection results are affected by the threshold setting, the detection accuracy is not high, and the diagnostic effect is not good

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