Improved electrode performance of LiAl_yCo_1-yO₂ prepared via sol-gel process

A significant improvement in capacity and cyclability of Al-doped LiCoO₂ cathode has been achieved by sol-gel process using acrylic acid as a chelating agent. The structure and electrochemical properties of the Al-doped LiCoO₂ powders at various calcination temperatures were investigated. The X-ray diffraction pattern for the Al-doped LiCoO₂ powders calcined at 600°C or above shows that these materials are a well-developed, layered HT-LiCoO₂ structures. The capacity fading of the Al-doped LiCoO₂ electrodes greatly reduced as the calcination temperature decreased. The sol-gel process makes possible the synthesis of Al-doped LiCoO₂ with α-NaFeO₂ structure at lower temperatures than solid-state synthesis, and thereby the enhancement of the capacity and cyclability of Al-doped LiCoO₂ electrode.