Apply an improved Peukert's equation based on temperature to the NiMH battery available capacity estimation

Battery available capacity varies with discharge current. Peukert's equation is a good way to estimate available capacity. But the practicability of Peukert's equation for The NiMH battery has to be verified. Especially, available capacity of The NiMH battery is influenced by temperature obviously. In this paper, discharge experiments under different current 9A,27A, 54A, 81A are undertaken at room temperature 25°C. and the Peukert coefficients n and k are calculated by available capacities and discharge times at the maximum discharge current and the minimum current. The result indicates battery available capacity estimated by Peukert's equation is practical in 25°C. In order to verify the practicability of Peukert's equation for the NiMH battery at low temperatures, these four discharge experiments are done at other three temperatures 0°C. -12°C. -18 °C. The result indicates, at low temperatures, Peukert's equation is practical for The NiMH battery at low current and unpractical in high current. An improved Peukert's equation based on temperature is proposed. The calculated data catch well with experimental data.