Lithium-rich layered cathode material Li1.2Mn0.54Ni0.13Co0.13O2 is synthesized by an optimized sol-gel method followed by two step calcining process.The X-ray diffraction pattern shows that the Li1.2Mn0.54Ni0.13Co0.13O2 materials have a layered α-NaFeO2 structure and single-phase compounds with good crystallinity.Electrochemical studies indicate that particle size,which is mainly determined by pH and calcining temperature,has little effect on the cycling performance.Samples of higher calcining temperature (900℃) have a better cycling performance because of well-arranged layered structure and better ordered superlattice existing in monoclinic Li2MnO3 phase.Emphatically,the way of mixing citric acid and acetate solution plays an important role of electrochemical performance.Li1.2Mn0.54Ni0.13Co0.13O2 with a 3wt% excess amount of lithium acetate,synthetized by adding citric acid dropwise to the acetate solution and calcining at the temperature of 900℃,shows a higher specific discharge capacity and capacity retention rate (95.5% at C/2 after 100 cycles).