Interphasial engineering for Ni-rich NMC cathode materials

Ni-rich LiNi1–x–yMnxCoyO2 (NMC: 1–x–y ≥ 0.6) are promising cathode materials for lithium-ion batteries (LIBs) due to their high reversible capacity and low cost. However, the fast capacity decay and voltage fading caused by interphasial instability require improvement. The unstable cathode–electrolyte interphase (CEI) and transition metal dissolution at higher voltages can lead to the drastic deterioration of electrochemical performance. In this review, recent approaches to novel electrolyte and additive design, cathode engineering including artificial CEI, and doping/coating on the surface of particles or the whole electrode are comprehensively summarized. The importance of multimodel and multiscale characterization methods in understanding the effects of interphasial chemistry on battery performance is highlighted.