Modeling of the diffusion phenomenon in a lithium-ion cell using frequency or time domain identification

The paper deals with the identification of a graphite/LiFePO4 Li-Ion cell, the model of which is based on an electric equivalent circuit. The paper focuses on the choice of the model used to represent the diffusion phenomena and on the parameters identification method. For this goal, two main models have been compared: a constant phase element model (CPE) and an hyperbolic tangent model (Tanh). These two models have been identified either using a frequency and a time domain method. The validity and accuracy of the model have been evaluated over a NEDC driving cycle.