Nanocubic Li4Ti5O12 Derived from H-Titanate Nanotubes as Anode Material for Lithium-Ion Batteries

Nanocubic lithium titanate (Li4Ti5O12, N-LTO) has been synthesized by a modified solid-state reaction using H-titanate nanotubes as titanium source and lithium carbonate as lithium source. The as-prepared N-LTO was highly crystalline with size ranging from 50 nm to 200 nm. The electrochemical performance of the N-LTO was investigated and compared with commercial nanoscale lithium titanate (C-LTO). The N-LTO electrode showed an initial discharge capacity of 181.0 mAh g(-1) at 0.5 C with capacity retention of 86.7% after 200 cycles. At a high rate of 10 C, the N-LTO electrode retained a high reversible capacity of 149.2 mAh g(-1), considerably higher compared with the value of 117.1 mAh g(-1) for C-LTO. The N-LTO electrode exhibited excellent long-term cycling stability with capacity retention of 82.6% at 5 C after 1000 cycles. A full cell of LiFePO4/N-LTO was tested, showing capacity retention of 78.7% at 1 C after 100 cycles.