Numerical and experimental investigation of the electrical and thermal behaviors of the Li-ion batteries under normal and abuse operating conditions

This paper presents the results of a comprehensive investigation of the electrical and thermal behaviors of the Lithium (Li)-ion batteries under normal and abuse conditions. In the first part of the study, an electrochemical-thermal coupled model is developed to predict the thermal and electrical characteristics of a Li-ion battery at 20 and 50 °C temperatures for varying discharge rates based on a detailed sensitivity analysis of the electrochemical and thermal model parameters. The experimental and model data are consistent, considering the discharging processes at 0.5, 1, and 1.5C rates under 20 and 50 °C operating temperatures. In the second part of the study, thermal abuse experiments are conducted by heating the Li-ion cell using the film heater at various charge states of battery. Simulations are carried out for the heating tests by enhancing the electrochemical-thermal model using the temperature-dependent Arrhenius equations. The results show that the thermal abuse model can predict the thermal runaway initiation time within the approximate 10 % margin of error, and the maximum surface temperature with 10.5 % of error compared to the experimental results of the completely charged Li-ion cell.