Variable Recursive Least Square Algorithm for Lithium-ion Battery Equivalent Circuit Model Parameters Identification

For SOC (state of charge) assessment techniques based on electrical circuit models, the parameters model are strongly biased by: battery aging, temperature, causing some errors in estimation SOC. One approach to solve this problem is update constantly. We suggest a new algorithm VRLS (variable recursive least squares) 2-resistor-capacitor (RC) network and estimate output voltage. compared squares (RLS) adaptive forgetting factor (AFFRLS) algorithms. assessment, we utilized real experimental data conducted Samsung 18650-20R lithium-ion cell. The tests indicate that RLS AFFRLS methods, recorded low distribution high error range, addition small predictive performance indicators (RMSE, MAE, MAPE) all tests, which implies has good parameter identification ability.