With the rapid development of portable electronic products and electric vehicles, the performance of lithium ion batteries has been put forward higher requirements. Compared with traditional lithium cobalt oxide cathode materials, nickel-rich layered metal oxides have higher energy density and lower raw material cost, and are considered as ideal cathode materials for lithium-ion batteries. However, its structural defects and unstable surface chemical properties will deteriorate the electrochemical properties, thermodynamic stability and safety performance. This paper reviews the research progress of modification of nickel-rich ternary cathode materials in recent years, aiming at providing important ideas for future design of nickel-rich ternary cathode materials and realizing their industrial application. Firstly, the inherent defects of nickel-rich cathode materials and the degradation mechanism of electrochemical performanceare introduced. Then, the modification strategies to improve the properties of nickel-rich materials by adjusting the interface structure are discussed, including coating electrochemical inert substances, designing element concentration gradient and core-shell structure, constructing core-shell heterostructure and controlling the thickness of the coating materials. After that, the strategies to improve the performance of nickel-rich cathode materials by bulk doping of elements are also summarized, including alkali metal-sites doping, transition metal sites doping, oxygen sites doping and synergy co-doping. Finally, the future development in this field is summarized and prospected,expecting to inspire more innovative ideas and strategies to promote the practical application of nickel-rich cathode materials.
