Fine-sized LiCoO₂ cathode powders prepared from the nano-sized cobalt oxide powders obtained by gas phase reaction method

Fine-sized LiCoO₂ powders were prepared by solid-state reaction method using nano-sized Co₃O₄ powders. Nano-sized Co ₃O₄ powders with regular morphology and narrow size distribution were obtained by spray pyrolysis method. The fine-sized LiCoO ₂ powders had slightly aggregated morphology and narrow size distribution even without milling process. The mean size of the LiCoO ₂ powders increased from 280 nm to 500 nm when the post-treatment temperature was changed from 500°C to 800°C. On the other hand, the LiCoO₂ powders prepared by conventional spray pyrolysis method at preparation conditions of high production rate had irregular morphology and broad size distribution. The initial discharge capacities of the fine-sized LiCoO₂ powders prepared by solid-state reaction method and the commercial product with micron size were each 151 mAh/g and 133 mAh/g, The discharge capacities of the fine-sized LiCoO₂ powders dropped from 151 to 135 mAh/g after 50 th cycle at a current density of 0.1 C.