Efficient coupled mechanical-electrical-thermal modeling and safety assessment of lithium-ion battery under mechanical abuse

The analysis and modeling of the multi-field coupling behavior of lithium-ion batteries under mechanical abuse has become a key focus in studying battery thermal runaway (TR). Unlike previous research methods, this paper proposes an efficient mechanical-electrical-thermal coupling modeling approach to accurately predict battery TR behavior under various conditions. A comprehensive assessment method for battery safety under mechanical abuse is also introduced. To enhance the computational efficiency of the coupling model, we simplified the mechanical, electrical, and thermal models and calibrated the model parameters through corresponding experiments. Under different battery states of charge (SOC) and various punch head sizes during mechanical abuse, the coupling model demonstrated strong consistency with experimental results in predicting force, voltage, and temperature. System simulations of mechanical abuse and extraction of TR characteristic parameters were conducted to comprehensively assess battery safety from both risk and hazard perspectives, quantitatively analyzing the impact of different SOCs and punch head sizes on battery safety. The multi-field coupling modeling method and safety assessment approach proposed in this paper provide valuable tools and guidance for predicting and assessing the mechanical safety behavior of lithium-ion batteries.