A simplified electrochemical model for modelling Li-ion batteries comprising blend and bidispersed electrodes for high power applications

Abstract

A fast computing electrochemical model has been developed in order to account for the electrothermal behavior of Li-ion batteries with multiple and/or multidispersed active materials in each electrode. In this study, the cell studied is a high power cell with lithium manganese spinel and lithium cobalt oxide at the positive and Lithium titanate at the negative with 2 particle populations. The model has been calibrated on the said cell and validated on realistic duty profile. It has been then compared against a state-of-the-art Newmann model that showed similar results for both global and inner behavior. However, due to the simplifications adopted for our modelling approach, calculation times of the newly developed model are significantly lower allowing to specific use where fast computing modelling approaches are required. Finally, this model has been used in order to understand the inner behavior of each electrode during constant current charge and discharges as well as hybrid electric vehicle duty cycles and further calculations have been performed to understand the impact of active material repartition in each electrode.