An algorithm for computing the lithium concentration in Li-ion battery electrode particles with the lithium concentration-stress coupling model

Abstract

How to compute the lithium concentration in Li-ion battery electrode particles fast and accurately is crucial in the study of physics-based Li-ion battery models. When computing the lithium concentration in Li-ion battery electrode particles with a high fidelity model, whether it can be achieved depends on the algorithm used. In this work, an algorithm for computing the lithium concentration in Li-ion battery electrode particles with the lithium concentration-stress coupling model is developed. Theoretically, providing that the parameters of the lithium concentration-stress coupling model are given, the lithium concentration in Li-ion battery electrode particles under any load current of Li-ion batteries whose amplitude is no higher than the given limit can be computed fast and accurately with the algorithm. To verify this, the algorithm is used in the State of Charge (SOC) estimation of two types of Li-ion batteries under different load currents. By timing the estimating processes and comparing the estimated results with the measured results, it can be concluded that the algorithm is effective.