LiCoO2 powders for lithium secondary battery were successfully prepared by the ultrasonic spray pyrolysis process. In this work, the statistical experimental design method was used to compare the characteristics (particle size, standard deviation, surface area, tab density) of the LiCoO2 particles according to the four parameters (synthesis temperature, sintering temperature, sintering time, sintering heating rate). The optimal synthesis conditions for the synthesis of LiCoO2 particles in ultrasonic spray pyrolysis process were to be obtained. The above-mentioned optimal conditions were used to prepare the particles with particle size 4.7 mu m (standard deviation: +/- 1.3%) and the experimental results were in a good agreement with simulated values. The oxide powders were characterized by scanning electron microscopy, X-ray diffraction and electrochemical method including charge-clischarge cycling. The characteristics as a cathode for lithium ion battery depended on the sintering temperature and sintering time. Consequently, LiCoO2 powders made by the ultrasonic spray pyrolysis process displayed a good electrochemical performance and the experimental design method was well applied. (c) 2005 Elsevier B.V. All rights reserved.