Abstract: The LiNi1/3Co1/3Mn1/3O2 was coated with Al2O3 by liquid impregnation method using nano Al2O3 ，Al（OH）3，and aluminum isopropoxide respectively as the starting materials.The effects of different Al2O3  sources coating on the surface of LiNi1/3Co1/3Mn1/3O2 material on the material′s electrochemical properties were investigated.Results of scanning electron microscopy（SEM） and X-ray diffraction（XRD） revealed that the product had parent hexagonal α-NaFeO2 structure and the Al2O3  was uniformly coated on the surface of material.Of all the three samples，the sample that using aluminum isopropoxide as the starting material had the best electrochemical performance.The initial discharge specific capacity at 0.1 C was 196.1 mA·h/g under the voltage range of 3.0~4.6 V. The capacity retention of the best sample was 95.6% at 1 C after 50 cycles.

Key words: LiNi1/3Co1/3Mn1/3O2 , coating, Al2O3 , cycling stability