Abstract：Lithium-ion battery cathode materials of Mg doped Li1.2Mn0.6Ni0.2O2 were prepared by combustion synthesis. The phase structures and morphologies of the as-prepared samples were characterized by X-ray diffractometer, Raman spectroscopy and scanning electron microscope, respectively, and their electrochemical performance was measured. Results show that the as-prepared samples have better hexagonal layered structure, with spherical-like appearance. Through Mg2+ doping, the initial coulombic efficiency, cyclic stability and rate capacity are efficiently enhanced for the Li1.2Mn0.6Ni0.2O2 material. When the Mg2+ content is 0.02, the battery sample exhibits excellent electrochemical performance.
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