A perspective on nickel-rich layered oxide cathodes for lithium-ion batteries

Nickel-rich layered oxides are one of the most promising cathode candidates for next-generation high-energydensity lithium-ion batteries. The advantages of these materials are high reversible capacity, high energy density, good rate capability, and low cost. However, they suffer from poor cyclability, particularly at elevated temperatures, and thermal instability which induces thermal runaway. In this review, we highlight the evolution of nickel-rich layered oxides from LiNiO2 to LiNi1-x-yCo(x)Mn(y)O(2) (1-x-y > 0.5) in view of cationic substitutions, state-of-the-art understanding of the capacity fading mechanisms that is related to a complex surface chemistry of the particles, and various modification strategies to enhance the surface stability. Based on these considerations, the remaining challenges and the future research direction are also discussed.