Xijin Xu, Meng Ding, Jiangmei Yin, Jinzhao Huang, Peiyu Hou
The urgent prerequisites of high energy-density and superior electrochemical properties have been the main inspiration for the advancement of cathode materials in lithium-ion batteries (LIBs) in the last two decades. Nickel-rich layered transition-metal oxides with large reversible capacity as well as high operating voltage are considered as the most promising candidate for next-generation LIBs. Nonetheless, the poor long-term cycle-life and inferior thermal stability have limited their broadly practical applications. In the research of LIBs, it is observed that surface/interfacial structure and chemistry play significant roles in the performance of cathode cycling. This is due to the fact that they are basically responsible for the reversibility of Li+ intercalation/deintercalation chemistries while dictating the kinetics of the general cell reactions. In this Review, the surface/interfacial structure and chemistry of nickel-rich layered cathodes involving structural defects, redox mechanisms, structural evolutions, side-reactions among others are initially demonstrated. Recent advancements in stabilizing the surface/interfacial structure and chemistry of nickel-rich cathodes by surface modification, core–shell/concentration-gradient structure, foreign-ion substitution, hybrid surface, and electrolyte additive are presented. Then lastly, the remaining challenges such as the fundamental studies and commercialized applications, as well as the future research directions are discussed.
The surface/interfacial structure and chemistry of nickel-rich cathodes involving structural defects, redox mechanisms, structural evolutions, side-reactions, etc., are initially presented. Recent advances on stabilizing its surface/interfacial structure and chemistry by surface modification, core−shell/concentration-gradient structure, foreign-ion substitution, hybrid surface and electrolyte additive are summarized. Finally, the remaining challenges including fundamental studies and commercialized applications, and the future research directions are also discussed.