An electrochemical-thermal coupling model for prismatic lithium-ion batteries over wide temperature range

Accurate and rapid prediction of battery thermal behavior can provide accurate basis for making battery use plan, which is beneficial for alleviating the influence of thermal effect on battery life and safety. A fast numerical solution method of electrochemical-thermal coupling model for prismatic lithium-ion batteries is proposed in this work. Firstly, based on an existing electrochemical single particle model and one-dimensional thermal resistance network, analytical expression of thermal resistance network model in two-dimensional space is obtained by theoretical formula derivation. Then, to calibrate the model parameters at different temperatures, temperature range is divided into several intervals, and optimal parameter sets at different intervals are obtained by excitation response analysis method and multi-group particle swarm optimization algorithm. Finally, to realize the accurate numerical simulation of the model, a double adaptive extended Kalman filter method is applied to further optimize the parameters in real time. Seen from the simulation results over wide temperature range, mean absolute errors of voltage and temperature are less than 30 mV and 0.12 K at −5–55 °C respectively, which indicates the capability of the developed model for high-precision numerical simulation over temperature range for prismatic lithium-ion batteries.