Junfu Li 1, Dafang Wang 1, and Michael Pecht 2
1School of Automotive Engineering, Harbin Institute of Technology, Weihai, 264209, Shandong, China
2CALCE, Center for Advanced Life Cycle Engineering, Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20740, USA
Abstract:
Most electrochemical models fail to accurately simulate lithium-ion battery behaviors at high C-rates (generally above 2C) and thus limit lithium-ion battery usage in many of today's applications, including electric vehicles and hybrid electric vehicles. To address this issue, the non-uniform concentration distribution effects that occur within the electrodes at higher C-rates must be included in the electrochemical model. The essential modifications to the model must incorporate solid-phase diffusion, liquid-phase diffusion, and reaction polarization. This paper develops an electrochemical model that considers high C-rate performance and assesses the model's performance for LiCoO2 batteries with charge/discharge rates up to 4C, and LiFePO4 batteries up to 5C.