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Summary: A dynamic coupled electro‐thermal model including the impact of the state of charge (SOC), inner temperature and current flux on resistance and heat generation rate is proposed for prismatic batteries, including the ohmic and polarization resistances and entropy coefficient. This model reflects the interaction between generation rate of heat and temperature distribution and is appropriate to be employed. Subsequently, the dynamic model is implemented to reveal the temperature increase of a Li‐ion prismatic battery with the capacity of 50‐Ah under the conditions of static and dynamic currents. Experiments are performed to demonstrate the model which is given in this article can precisely describe the thermal behavior under the conditions of static and dynamic currents and different ambient temperatures, with an average relative error of 5.87% for the static condition and of 11.81% for the dynamic condition. In addition, comparative studies are utilized to decide the application range of the dynamic model. It shows according to the results that it should be used for the temperature prediction under the condition of dynamic current. As for the static current condition, the static model ignoring the effect of current can replace the dynamic model, although the temperature prediction precision of the dynamic model is slightly higher than that of the static model. Finally, the proposed dynamic model is compared with a resistance‐based thermal model where the heat generation depends only on SOC and is demonstrated to be superior to its counterpart. [ABSTRACT FROM AUTHOR]

Summary: This paper develops an electro‐thermal coupled model for a pouch battery which considers the influence of the electric potential distribution and thermal behaviours of tabs on the distributions of heat generation and temperature. This model reflects the connection between electric potential distribution and the heat generation distribution. Then, the proposed electro‐thermal model is used to predict the thermal behaviour of a lithium‐ion pouch battery under the conditions of various discharge currents and environmental temperatures. Tests are implemented to verify the prediction precision of the proposed thermal model. The results show that the electro‐thermal coupled model can accurately predict both the temperature distribution and its rise. At 1 C discharge rate, the average mean static absolute errors (MSAEs) in the positive and negative tabs for all the ambient temperatures are 1.083 K and 0.377 K, respectively, and the average MSAE in the battery body is only 0.627 K; at the discharge rate of 3.5 C, the respective average MSAEs are 1.643 K for the positive tab, 0.581 K for the negative tab, and 0.889 K for the battery body. Last, the influence of the thermal contact resistance on the prediction of the tab temperature is studied. If it is considered in the thermal model of tabs, the predicted tab temperature is closer to the tested value and the MSAE can be limited within 2.65 K for the positive tab and 0.83 K for the negative tab in the cases researched. [ABSTRACT FROM AUTHOR]