High rate lithium intercalation properties of V2O5/carbon/ceramic-filler composites

Composite electrodes of amorphous vanadium pentoxide/carbon/ceramic filler were prepared by mixing vanadium oxide hydrosol, acetone, carbon and ceramic fillers, and by extension on aluminum foil. High rate charge/discharge property of the composite electrode was examined, and the effect of fillers was discussed. The composite electrode had a porous structure, in which pores were 0.5–3 μm in diameter and penetrated through the composite. The composite electrode showed a large capacity of 98 mA h/g-electrode at a high current density of 17.2 mA/cm2 (270 A/g-electrode). The relation between discharge capacity and current density was calculated by solving the simplified diffusion equation. The apparent diffusion coefficient of lithium ion in the composite electrode was found to be 10 times larger than that of electrode without fillers.