摘要

Lithium-rich manganese-based layered cathode materials (xLi(2)MnO(3 )center dot (1-x ) LiMO2, M = Ni , Co , Mn , etc.) , owing to their high specific capacity (>= 250 mAh.g(-1)) , low cost and environmental friendliness , are considered as one of the best candidate cathode materials for the new generation of lithium-ion batteries. However, these materials suffer from severe capacity/voltage fading during the cycle process and low rate capability which seriously hinder commercial development. In this paper, we analyze the structural characteristics and the reasons which lead to the deterioration of the electrochemical performance of the lithium-rich manganese-based layered cathode materials , systematically review the latest progress and achievements on improving the stability of the cathode materials , and the efforts to improve the electrochemical properties of the cathode materials through bulk doping and surface modification. In this process, the effects of bulk doping at different sites and different coating materials on the structure and electrochemical behavior of lithium-rich manganese-based layered cathode materials are further analyzed. Finally , considering the advantages and disadvantages of the two modification methods of bulk doping and surface coating, a joint modification mechanism combining bulk doping and surface coating has been suggested to improve the stability of lithium-rich cathode materials in the long cycle process, and the introduction and prospect of this mechanism are also given.