A new electrochemical impedance spectroscopy model of a high-power lithium-ion battery

Abstract

This paper presents an electrochemical impedance spectroscopy battery model including an electrical double layer capacitance, which can comprehensively depict the internal state of the battery. Based on the porous electrode theory, this model can obtain a complete spectrum of cell impendence. In addition, the EIS data recorded by an appropriate measurement instrument are consistent with the records of theoretical impedance derived from the model in terms of room temperature. To establish the relationship between internal parameters and external spectrum, a virtual simulation experiment is conducted to illustrate the effect of key parameters on EIS. According to the simulation experimental results, the model can be used to identify internal parameters based on the practical external spectrum. In the last part of the paper, a preliminary parameter identification strategy is proposed to study the relationship between battery internal parameters and external conditions.