A Quantitative Measurement Method for Lithium Plating Quantization in Lithium Ion Batteries Based on Electrochemical Impedance Spectroscopy

Lithium-ion batteries (LIBs) have many advantages, such as high energy density, no memory effect, long cycle life, etc., and are widely used in energy, automobile, consumer electronics and other industries. In unreasonable conditions such as overcharge, high power rate and low temperature, the LIBs will make lithium ions deposit in the form of lithium metal on the surface of the negative electrode. This phenomenon is often called lithium plating. In this paper, accelerated lithium plating experiments are designed for LIBs. Detection and quantification of lithium plating were carried out based on electrochemical method under different lithium plating degrees. The electrochemical impedance spectra (EIS) of lithium-ion batteries with different degrees of lithium plating were measured, and the characteristic parameters of the EIS were extracted, and the correlation between the characteristic parameters of the EIS and the quantified degree of lithium plating was analyzed. Then, a BP neural network was used to analyze the error and verify the validity of the quantified amount of lithium.