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xLi2MnO3·(1-x)LiNi0.4Co0.2Mn0.4O2(x=0.5) powders were synthesized from co-precipitated spherical metal carbonate,Ni0.2Co0.1Mn0.533(CO3)x.It has been found that the preparation of metal carbonate was significantly dependent on synthetic conditions,including the coprecipitation temperature,kind of precipitator,and stirring speed.The results of SEM showed that the shape of precursor powders was sphere-like.And the final product,Li1.167Ni0.2Co0.1Mn0.533O2,was also significantly uniform due to the homogeneity of the metal carbonate precursor,Ni0.2Coo.1Mn0.533(CO3)x,.LiLi67Ni0.2Co0.1Mn0.533O2 has α-NaFeO2 layered structure,as confirmed by XRD analysis.The average particle size was about 10μm in diameter and the particle size distribution was relatively narrow.The results of XRD and chemical analysis showed that the synthesized Li1.167Ni0.2Co0.1Mn0.533O2 had lower cation mixing and good layered structure,and the chemical composition is almost LiL1.198Ni0.193Co0.103Mn0.537O2.Electrochemical properties during charge and discharge were discussed.In the voltage range of 2.0-4.8 V,the discharge capacity of Li1.167Ni0.2Co0.1Mn0.533O2 was 340 mAh/g.