A review on the electrochemical reaction of Li-rich layered oxide materials

Lithium-rich layered oxide materials xLi2MnO3·(1 − x)LiMO2 (M = Mn, Co, Ni, Fe, Cr, etc.) are promising cathode candidates for high energy Li-ion batteries because of their high specific capacities (>250 mA h g−1) and reasonable working voltage. The high capacity comes from the activation of inactive Li2MnO3 in the high voltage range (>4.5 V). However, many adverse factors appear along with the activation process, such as low initial coulombic efficiency and severe capacity and voltage fading during cycling, which limit the commercialization of Li-rich materials. This review based on existing research on the electrochemistry of Li-rich materials presents an introduction to the reaction mechanism, challenges and strategies and prospects.