Morphological and electrochemical properties of LiV₃O ₈ cathode powders prepared by spray pyrolysis

Lithium trivanadate (LiV₃O₈) powders are prepared by spray pyrolysis. The precursor powders of LiV₃O₈ obtained by spray pyrolysis have spherical and rod-like morphologies. The LiV ₃O₈ powders post-treated at 300°C and 400°C also have spherical and rod-like morphologies. However, the LiV₃O ₈ cathode powders post-treated at 500°C consist of only rod-like crystals. The crystalline structure of the precursor powders that were directly prepared by spray pyrolysis comprised of LiV₃O₈ layers along with a small amount of β-Li_0.33V₂O₅ impurity. The peak due to β-Li_0.33V₂O₅ persisted in the XRD spectrum even after posttreatment at 300°C. On the other hand, crystalline structures of the powders post-treated at 400°C and 500°C comprised pure LiV₃O₈ layers. The initial discharge capacities of the LiV₃O₈ cathode powders decrease from 344mAhg^-1 to 261mAhg^-1 when the post-treatment temperatures increase from 300°C to 500°C. The discharge capacities of the LiV₃O₈ cathode powders obtained after post-treatment at 400°C and 500°C are approximately 255mAhg^-1 and 236mAhg^-1, respectively, after 40 cycles.