The Li-rich layered metal oxides(Li[NixCoyMnz]O2(0 ≤ X,y,z 〈 1))(noted as LMCN)are considered as one of promising cathode materials owing to high special capacity and working voltage.However,LMCN suffers from poor cycling stability and fast voltage fading caused by structure collapse.Inspired by its superior thermal and chemical stability,LiMnPO4(LMP)is used to coat LMCN to enhance structrual stability.In this work,LMP-LMCN samples with different LMP content(1 wt.%,3 wt.%,5 wt.%)were synthsized with assistance of supercritical CO2.Among them,LMCN coated with 3 wt.%LMP(LMP3-LMCN)sample exhibits high initial coulombic efficiency of 81.1%,good capacity retention rate of 79.2%after 100 cycles with only 0.47V voltage fading at 30 mA g-1 which is better than others.The improvement electrochemical performance of LMCN was attribute to LMP layer preventing the Li2O vacancy from being occupied by the transition metal ions and suppressing phase transformation.