Abstract: In order to solve the problems of high full-order structure complexity of the existing electrochemical mechanism models and the inability to accurately describe the battery temperature change process,a simplified electrochemical model coupled with the thermodynamic model is proposed in this paper. Firstly,the simplified electrochemical-thermodynamic coupling model is established.Then,the relevant parameters of the model are obtained through intelligent identification algorithm. The experimental results show that the model established by this method has a good fitting effect between the simulated curve and the actual test curve under a wide ambient temperature range and common discharge rate conditions,and can describe the changes of battery voltage,current and temperature field. This model describes the electrochemical and thermodynamic behavior of batteries with low complexity and high precision,which is beneficial to the subsequent research of battery state estimation and remaining life prediction.