A Statistical Approach for Electrochemical Impedance Spectroscopy Analysis on LFP Batteries’ State of Charge

A challenge that concerns many applications where energy storage devices are employed is the online and real-time estimate of the State of Charge (SoC) of batteries. Electrochemical Impedance Spectroscopy (EIS)-based methods are among the most used to estimate the battery SoC. In this work, a purely statistical approach has been proposed to search for correlations between the SoC and the impedance of the batteries. For this purpose, an experimental dataset consisting of 7 Lithium Iron Phosphate batteries was created, on which the Kernel Density Estimation technique was implemented. The obtained preliminary results have demonstrated the possibility of identifying correlations between some output parameters of the Kernel Density Estimation technique and the battery SoC.