The synthesis and electrochemical characteristics of LiCoxMnyNi1-x-yO2 as cathode materials for rechargeable lithium-ion batteries were investigated. The precursor CoxMnyNi1-x-y(OH)(2) was obtained by the chemical co-precipitation method. LiCoxMnyNi1-x-yO2 (0 less than or equal to x less than or equal to 0.3, and y = 0.2) was prepared by heating a mixture of CoxMnyNi1-x-y(OH)(2) and Li2CO3 at 850-900 degreesC for 24 h in air. The X-ray diffraction (XRD) patterns indicated that pure phase LiCoxMnyNi1-x-yO2 was obtained. The scanning electron micrographs (SEMs) show that the synthesized LiCoxMnyNi1-x-yO2 compounds have good micro-morphology and uniform particle size. The electrochemical properties of these materials such as the galvanostatic charge-discharge performance and cyclic voltammetry were systematically measured. (C) 2003 Elsevier Science B.V. All rights reserved.