Nitrogen-doped carbon coated Li ₄Ti ₅O ₁₂ nanocomposite: Superior anode materials for rechargeable lithium ion batteries

Nitrogen-doped carbon coated Li ₄Ti ₅O ₁₂ (NC-LTO) nanocomposite as an anode material for lithium-ion batteries (LIBs) is prepared with acetyl glucosamine as carbon source by pre-coating process combined with ball milling. X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy are used to characterize the NC-LTO materials. The results show that NC-LTO samples exhibit the obvious improvements in rate capability and cycling performance compared with the LTO samples coated by carbon (C-LTO) derived from sugar and pure LTO samples. The carbon pre-coating process could significantly decrease the agglomeration of TiO ₂ precursors and the uniformly coated nitrogen-doped carbon increase the interfacial stability and electric conductivity of LTO. At the charge-discharge rate of 0.2 C, 5.0 C and 10.0 C and 20.0 C, the discharge capacities of NC-LTO samples are 167.4, 146.3, 133.4 and 128.2 mAh g ^-1, respectively. After 1000 cycles at 1 C, its capacity retention is 95.9% with nearly ignored capacity fading.