Abstract: In this study, a pouch lithium ion battery was fabricated by using NCM as cathode material and LTO as anode material. Four different N/P ratios were designed by changing the capacity of LTO anode. The battery capacity, high temperature storage and cycling performance were studied, and the results show that increasing the N/P ratio can improve the initial discharge capacity of the battery. However, increasing the N/P ratio will increase the potential of the positive electrode, and the electrolyte will be easily oxidized on the positive electrode side, especially near the fully charged state. The low N/P ratio may ensure that the positive electrode has a lower electrode potential, which reduces the side effects of the LTO battery and improves the high temperature storage and cycling performances.

Key words: pouch LTO lithium ion battery, N/P ratio, battery capacity, high temperature storage and cycling performance