context: Research focus on cathode materials for LIBs is currently going through a paradigm shift where the previously overlooked disordered rocksalt (DRS) materials are receiving an increasing level of interest. It was reported that Li-rich materials with a high Li-to-TM ratio allow the formation of percolating network with low energy barriers for Li diffusion, which leads to good transport properties while its structural integrity is retained. Several Li-rich transition metal oxides with a DRS structure such as Li1+xTi2xFe1−3xO2 (0 ≤ x ≤ 0.333), Li1.2Ni1/3Ti1/3Mo2/5O2, Li1.2Ti0.4Mn0.4O2, Li1.3Nb0.3Fe0.4O2 ( ) and Li1.3Nb0.43Ni0.27O2 ( ) have been studied, and their high reversible capacities showed a promising prospect of discovering new cathode material in much less explored domain. Li2VO2F is the first Li-rich DRS material where O was partially substituted by F. The substitution increases the performance of the cathode such as discharge capacity and nominal voltage.
answer: Li2VO2F 