Challenges and strategies of lithium-rich layered oxides for Li-ion batteries

Lithium-ion batteries are considered a promising energy storage technology in portable electronics and electric vehicles due to their high energy density, competitive cost, and environmental friendliness. Improving cathode materials is an effective way to meet the demand for better batteries, of which the utilization of high-voltage cathode materials is an important development trend. In recent years, lithium-rich layered oxides have gained great attention due to their desirable energy density. This review presents the relationships between lattice structure and electrochemical properties, the underlying degradation mechanisms, and corresponding modification strategies. The recent progress and strategies are then highlighted, including element doping, surface coating, morphology design, size control, etc. Finally, a concise perspective for future developments and practical applications of lithium-rich layered oxides has been provided.