Nanocrystalline V2O5 flake was simply synthesized via a citric acid assisted sol-gel method. The citric acid assistant improved the morphology and electrochemical performance Of V2O5. TGA-DTA, XRD, SEM, TEM, CV and charge-discharge tests were used to characterize the as-prepared V2O5 powder. SEM and TEM images showed that the product had a stacked-up-flakes morphology. A high initial discharge specific capacity of 798 mAh/g was obtained in the charge-discharge cycle. (c) 2005 Elsevier B.V. All rights reserved.