Interface chemical reconstruction with residual lithium compounds on nickel-rich cathode by nonstoichiometrical MoO3-x coating enables high stability

The layered lithium nickel-rich cathodes have become one of the most promising candidates for next-generation lithium-ion batteries with high energy density , However, the nickel-rich cathode suffers from a rapid decay of capacity due to their intrinsic instability and undesirably residual lithium compounds originated from LiNiO 2 structural changes on the surface, hindering large-scale commercial application. Herein, a continuous and uniform oxygen vacancy enriched-MoO 3-x coating was successfully synthesized and reacted residual lithium compounds as a functional layer on the cathode. Such chemically reconstructed coating (Li 2 MoO 4 ) strategy endows the 1 wt% MoO 3-x coated NCA cathode with a fast Li + ions transport and enhanced structural stability , leading to an outstanding discharge capacity of 214.0 mAh g −1 at 0.1C (1C = 270 mA g −1 ), a better capacity retention of 80.3 % after 120 cycles at 0.5C, and an excellent high rate capability of 120 mAh g −1 at 5C cycled in voltage range of 2.75 V–4.3 V. This work provides an effective strategy to modulate surface structure towards advanced Ni-rich cathodes for high-performance lithium-ion batteries.