An Inverse Method for Estimating the Electrochemical Parameters of Lithium-Ion Batteries

Abstract

This paper is the second part of a two part study on parameter estimation of Li-ion batteries. The methodology was developed in Part I. In Part II, the methodology is tested for LiCoO2, LiMn2O4 and LiFePO4 positive electrode materials. An inverse method combined to a simplified version of the Pseudo-two-Dimensional (P2D) model is used to identify the solid diffusion coefficients (Ds,n and Ds,p), the intercalation/deintercalation reaction-rate constants (Kn and Kp), the initial SOC (SOCn,0 and SOCp,0), and the electroactive surface areas (Sn and Sp) of Li-ion batteries. Experimental cell potentials for both low and high discharge rates provide the reference data for minimizing the objective function in the best time interval. For all cases simulated, the numerical predictions show excellent agreement with the experimental data.