High-capacity Li[Li0.2Mn0.54Ni0.13Co0.13]O2 has been successfully synthesized as a cathode material for Li-ion battery by hydrothermal method. The prepared materials are characterized by XRD, SEM, TEM, EDS, XPS and electrochemical measurements. The XRD result shows that Li[Li0.2Mn0.54Ni0.13Co0.13]O2 material formed a pure phase. SEM and TEM images present a uniformly distributed nanosize of 20–200nm. The results of CV, charge–discharge tests indicate that this material possesses high discharge capacity and quite good cycling stability. It delivers 251.9mAhg−1 and 107.5mAhg−1 for the first cycle and remains 139.4mAhg−1 and 82.7mAhg−1 after 500 cycles, respectively, corresponding to 1C and 10C.