The performance of vanadium oxide nanorolls as cathode material in a rechargeable lithium battery

Vanadium oxide nanorolls have for the first time been successfully used as cathode material in a rechargeable lithium battery. The rolls consist of va nadium oxide sheets arranged in a scroll-like manner. The layers are separa ted by structure directing templates (e.g., primary amines) which can be re adily exchanged by Various metal cations without destroying the tubular str ucture. X-ray diffraction (XRD) and transmission electron microscopy were u sed to investigate the morphology and structure of the rolls. Performance a s an electrode material was tested by galvanostatic cycling in the potentia l range 1.8-3.5 V (vs. Li/Li+). The capacities were found to be closely dep endent on the type-of lithium salt used in the electrolyte. Three salts wer e tested, LiBF4, LiPF6, and LiN(CF3SO2)(2). The imide salt, LiN(CF3SO2)(2), proved to give the best result with initial capacities >200 mAh/g. The mat erial cycled reversibly for at least 100 cycles. XRD results indicate that the tubular structure is preserved even after prolonged cycling. (C) 2001 T he Electrochemical Society.