Electrochemical Modeling of Fast Charging in Batteries

Abstract

AbstractThe 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 (Ucell), anode (Ua), and cathode (Uc) at high C‐rates. Herein, Ucell, Ua, and Uc are experimentally obtained under various C‐rates (0.1–2C) and identified the charge transfer resistance of the cathode (RCT,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 Ua and Li‐ion concentration prediction. 2D reconstruction structures for the cathode is established with RCT,c effect considered. Finally, the Ua, Uc, and Ucell 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.