Hydrothermal-assisted sol-gel synthesis of Li4Ti5O12/C nano-composite for high-energy lithium-ion batteries

•Li4Ti5O12/C is synthesized by hydrothermal-assisted sol-gel method.•Li4Ti5O12/C shows the particle size range of 20–75 nm.•Li4Ti5O12/C shows excellent rate capability of 127.8 mAh g− 1 at 20C and only 3.4% capacity loss after 1000 cycles at 5C.

Agglomerate spheric Li4Ti5O12/C nano-composite is synthesized using Ti-(OC4H9)4, LiAc · 2H2O and polyvinylpyrrolidone through a hydrothermal-assisted sol-gel reaction and is characterized by X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Test results indicate that compared with the electrochemical performance of bulk Li4Ti5O12, the electrochemical performance of Li4Ti5O12/C has been greatly improved. Li4Ti5O12/C has a high-rate performance of 127.8 mAh g− 1 at 20 °C and a capacity retention of 146.7 mAh g− 1 after 1000 cycles at 5 °C. It is therefore concluded that Li4Ti5O12/C nano-composite is a promising candidate for applications in high-rate lithium ion batteries.