Transient Electrochemical Modeling and Performance Investigation Under Different Driving Conditions for 144Ah Li-ion Cell with Two Jelly Rolls 2023-01-0513

Recently, the automotive industry has experienced rapid growth in powertrain electrification, with more and more battery electric vehicles (BEV) and hybrid electric vehicles being launched. Lithium-ion batteries play an important role due to their high energy capacity and power density, however they experience high heat generation in their operation, and if not properly cooled it can lead to serious safety issues as well as lower performance and durability. In that way, good prediction of a battery behavior is crucial for successful design and management. This paper presents a 1D electrochemical model development of a 144 Ah prismatic rolled cell using the GT-Autolion software with a pseudo 2D approach. The model correlation is done at cell level comparing model results and test data of cell open circuit voltage at different temperatures and voltage and temperature profile under different C-rates and ambient temperatures. After the cell level validation, a lumped battery pack model was submitted to different drive cycles: EPA, CLTC-P and WLTC having the battery current as input and comparing battery voltage and SOC. The cell level model presented good correlation with test data and the battery model proved capable of accurately make performance predictions. This model be used for further advanced investigations, such as cell degradation, thermal runaway and gas generation.