Electrochemical Modeling of Fast Charging in Batteries

Abstract The acceleration of fast charging capabilities has emerged as a pivotal objective within the realms of the battery, electric vehicle, and energy storage sectors. However, the classical electrochemical models are not able to describe voltages of the cell ( U cell ), anode ( U a ), and cathode ( U c ) at high C‐rates. Herein, U cell , U a , and U c are experimentally obtained under various C‐rates (0.1–2C) and identified the charge transfer resistance of the cathode ( R CT,c ) as the primary rate‐limiting factor. Thus, the anode is established as a multi‐scale coupling model with Fick's law and phase separation model applied, to discuss their effect on U a and Li‐ion concentration prediction. 2D reconstruction structures for the cathode is established with R CT,c effect considered. Finally, the U a , U c , and U cell are successfully predicted at different C‐rates. Results propose an accurate and versatile electrochemical model and highlight the importance of considering limiting factors in electrochemical modeling for fast charging.