Abstract
Li-rich layered ternary cathode material xLi2MnO3∙·(1−x)LiMO2 (M=Ni、Co、Mn，0<x<1) has the characteristics of high capacity and low cost. It is an attractive cathode material for high energy density lithium ion batteries and also a research hotspot for the development of lithium ion batteries in the future. However, its low coulomb efficiency, poor cycling ability, serious voltage attenuation and other problems seriously hinder the development of materials. In recent years, a lot of researches research efforts have been made on understanding the working mechanism of materials and improving the properties of cathode materials to improve the electrochemical properties of lithium ion batteries, and important progress has been made. In this paper, the charge-discharge working principle and degradation mechanism of materials, the effects of bulk doping and surface coating on cycling stability of Li-rich cathode materials are introduced, which aims to deepen the understanding on the working mechanism of such materials, and guide to explore more effective cathode materials