Morphological and electrochemical properties of LiV 3O 8 cathode powders prepared by spray pyrolysis

Abstract

Lithium trivanadate (LiV 3O 8) powders are prepared by spray pyrolysis. The precursor powders of LiV 3O 8 obtained by spray pyrolysis have spherical and rod-like morphologies. The LiV 3O 8 powders post-treated at 300 °C and 400 °C also have spherical and rod-like morphologies. However, the LiV 3O 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 LiV 3O 8 layers along with a small amount of β-Li 0.33V 2O 5 impurity. The peak due to β-Li 0.33V 2O 5 persisted in the XRD spectrum even after post-treatment at 300 °C. On the other hand, crystalline structures of the powders post-treated at 400 °C and 500 °C comprised pure LiV 3O 8 layers. The initial discharge capacities of the LiV 3O 8 cathode powders decrease from 344 mAh g −1 to 261 mAh g −1 when the post-treatment temperatures increase from 300 °C to 500 °C. The discharge capacities of the LiV 3O 8 cathode powders obtained after post-treatment at 400 °C and 500 °C are approximately 255 mAh g −1 and 236 mAh g −1, respectively, after 40 cycles.