TiO 2–B nanowires as negative electrodes for rechargeable lithium batteries

Abstract

TiO 2–B nanowires (20–40 nm diameter) may be prepared in high yield by a simple synthetic procedure. Lithium may be intercalated up to Li 0.91TiO 2–B corresponding to a capacity of 305 mAh g −1 and at a potential of 1.6 V versus Li + (1 M)/Li. This can be compared with 160 mAh g −1 for Li 4Ti 5O 12 and 165 mAh g −1 for TiO 2-anatase. Following a small irreversible capacity on the first cycle, capacity retention is excellent corresponding to a fade of <0.1% per cycle at a rate of 50 mA g −1. A capacity of 160 mAh g −1 is sustained at a rate of 500 mA g −1 in electrodes that were not optimised for rate capability. Results to date indicate that the small irreversible loss of capacity on the first cycle is not associated with a SEI layer.