Li3V2(PO4)3-coated Li1.17Ni0.2Co0.05Mn0.58O2 as the cathode materials with high rate capability for Lithium ion batteries

In this work, Lithium rich layered oxide Li1.17Ni0.2Co0.05Mn0.58O2 (LNCMO) is prepared and coated with Li3V2(PO4)3 (LVP) by a chemical deposition method. The surface modification with LVP is introduced into Li-rich layered oxides LNCMO for the first time. After 100 cycles of charging and discharging at various rates, the Li3V2(PO4)3-coated Li1.17Ni0.2Co0.05Mn0.58O2 (LVP-coated LNCMO) (5 wt%) still provides a large capacity of 261.4 mAh g-1, much higher than the pristine LNCMO (211.5 mAh g-1). At 5 C rate, the LVP-coated LNCMO exhibits a stable cyclic capacity of 153.4 mAh g-1, higher than 114.1 mAh g-1 of the pristine LNCMO. The electrochemical impedance spectroscopy (EIS) analysis demonstrates the LVP coating layer can suppress interaction between the cathode surface and the electrolyte and enhance the kinetics of lithium-ion diffusion, contributing to the stable cyclic performance with more cyclic capacity as well as at the high current density.