Crystallinity-Controlled Titanium Oxide-Carbon Nanocomposites with Enhanced Lithium Storage Performance

Abstract

Nanocomposites of crystalline-controlled TiO2carbon are prepared by a novel one-step approach and applied in anodes of lithium ion batteries. In our nanocomposite anodes, the Li+ capacity contribution from the TiO2 phase was enormous, above 400 mAh?g-1 (Li1+xTiO2, x>0.2), and the volumetric capacity was as high as 877 mAh?cm-3 with full voltage utilization to 0 V versus Li/Li+, which resulted in higher energy density than that of state-of-the-art titania anodes. For the first time, it was clearly revealed that the capacity at 1.2 and 2.0 V corresponded to Li+ storage at amorphous and crystalline TiO2, respectively. Furthermore, improvements in the rate capability and cycle performance were observed; this was attributed to resistance reduction induced by higher electrical/Li+ conduction and faster Li+ diffusion.