LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement, electron scanning microscopy and electrochemical measurements. Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750 ℃ with 105% lithium content has fine particle sizes around 200 nm and homogenous sizes distribution. The initial discharge capacity for the powder is 184 mA?h/g between 2.7 and 4.3 V at 0.1C and room temperature.