A Transient-Based Approach for Estimating the Electrical Parameters of a Lithium-ion Battery Model

This paper describes a transient-based approach for estimating the impedance parameters of a lumped-element electrical circuit model for a lithium-ion battery. In this methodology, a small test signal is superimposed on top of the battery load to trigger its transient dynamics. The resulting terminal voltage and current are measured, and a non-linear least-squares routine is used to estimate the parameters of the battery model. Experimental results obtained at consistent temperatures demonstrate that the parameter values depend on state-of-charge. The approach requires minimal hardware and could be used to form the basis of a robust on-line monitoring system.