Evaluation of Temperature Effect on the Performance of Li-ion Batteries in the Charge/Discharge Process by ISO 12405-1 Test: (I) LiFePO4 Battery Packs of Electric Vehicles

Evaluation of Temperature Effect on the Performance of Li-ion Batteries in the Charge/Discharge Process by ISO 12405-1 Test: (I) LiFePO4 Battery Packs of Electric Vehicles

The present work is reported in two parts in series. In the first part we perform the ISO 12405-1 test for two packs of lithium-ion batteries of EV (Electric Vehicle) under constant current rate during the charge and discharge process to study the effect of environmental temperature on the reliability performance of batteries packs. The evaluated items include the voltage, the current, the capacity, the energy and the temperature on the surface of batteries packs. The equipment for the ISO 12405-1 test used in the performance evaluation of commercial car batteries is of high class with high precision and accuracy on an industrial scale, and therefore the test data are provided for the internal use of enterprises only, and very few are published in literatures. The results indicate that the higher the surrounding temperature, the more complete the internal chemical reaction in the battery is and the higher the efficiency of the batteries is. It is the main contribution of this paper that the experiment results can be used as a reference for the design of battery packs to provide to EV manufacturers and propulsion battery suppliers.