Technical Paper
Parameterization of an electrochemical battery model using impedance spectroscopy in a wide range of frequency
2024-04-09
2024-01-2194
The electrochemical pseudo-two dimensional (P2D) model is one of the most promising approaches that provide suitable physical depth at reasonable computational costs for the simulation of lithium-ion batteries. The parameterization of the P2D model plays an important role as it decides about the acceptance and application range of subsequent simulation studies. Electrical impedance spectroscopy (EIS) is commonly applied to characterize the batteries and to obtain the exchange current density and the electrode diffusion coefficient of a given electrode material. EIS measurements performed with frequencies ranging from 1 MHz down to 10mHz typically do not cover clearly isolated solid state diffusion processes of lithium-ions in positive or negative electrode materials. To extend the frequency range down to 10µHz, the distribution relaxation times (DRT) is a sound analysis method.