The layered LiMO2 (M = Ni, Co and Mn) materials LiNi1/3Co1/3Mn1/3O2 and LiNi0.4Co0.2Mn0.4O2 are synthesized by rheological phase method. Sb2O3-modified phases are further obtained by mechanical ball milling treatment. The structure and morphology of the bare and modified samples are characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Charge/discharge tests indicate that the modified phases all improve cycling stability, rate capability and thermal safety. Careful comparison of the charge/discharge profiles reveals that the serious polarization increment in cycling is suppressed in the Sb2O3-modified LiMO2 electrodes. AC impedance shows that Sb2O3/LiNi1/3Co1/3Mn1/3O2 electrode has smaller R ct and R f value. Further analysis proves that Sb2O3 hinders the reaction between electrolyte and cathode during charge/discharge process and helps to stabilize the SEI. Other experiments prove that using Sb2O3-coated separator can achieve similar positive effect on layered LiMO2 cathode.