To improve the performance of power batteries at low temperature and reduce the dependence on the offline measurement equipment in obtaining the battery resistance, a novel thermoelectric coupling model has been employed for accurately calculating the resistance of the battery at different currents and temperatures. The Butler-Volmer(BV) equation has been proposed to describe the electrochemical reaction process of the battery. Compared with the traditional method, theoretical results show that the proposed model can accurately calculate the battery resistance and maintain the maximum calculation error less than 2mΩ. The proposed method has the potential to calculate the impedance timely and accurately.
Keywords Batteries, low temperatures, thermoelectric coupling model.