Effect of lower cut-off voltage on LiNi0.8Co0.1Mn0.1O2/graphite–SiOx pouch battery

Long-term cycle life and high safety are important performances of lithium-ion power batteries. Voltage windows have a significant impact on battery cycle life and safety. While the mechanism by which an upper cut-off voltage affects the performances of lithium-ion batteries has been extensively studied, the effect of a lower cut-off voltage (LCV) on the cycle life and safety of lithium-ion batteries, especially nickel-rich layered oxide/graphite–SiOx batteries, is poorly understood. In this work, the as-prepared LiNi0.8Co0.1Mn0.1O2/graphite–SiOx pouch batteries have been cycled with different LCVs. When LCVs increase from 2.80 to 3.00 V, the capacity retention of the batteries increases from 90.66 to 93.98% in the 500 cycles, and the average temperature rise in discharging process decreases from 11.3 to 9.1 °C at the second stage. The resistance of batteries reduces because of the increase of LCVs, resulting in the decreased temperature rise and side reaction of the batteries. The increase of LCVs of batteries will be conducive to improving the cycle life and safety of batteries. This study provides a new direction for selecting voltage windows of batteries and a new idea for improving cycle and safety performances of batteries.