In situ coating of graphene-like sheets on Li4Ti5O12 particles for lithium-ion batteries

•Li4Ti5O12 particles were synthesized with very thin graphene-like sheets in situ coating.•Liquid-polyacrylonitrile was used as the carbon source to form graphene-like coating sheets.•Li4Ti5O12 particles were prepared by the solid ball-milled method.•LTO-1%CB-20%LPAN own high specific capacity and excellent cycling stability at high rate.

Li4Ti5O12 particles are synthesized coated with very thin graphene-like sheets in situ using liquid-polyacrylonitrile (LPAN) as the carbon source and added utilized conductivity additives to improve the conductivity of the electrode materials. The crystalline structures of Li4Ti5O12 with 20% LPAN and different conductivity additives composites were examined by XRD. The structure and electrochemical performance of the graphene-like sheets coated Li4Ti5O12, with conductivity additives added, was systematically investigated. The electrochemical performance also revealed that the graphene-like sheets significantly improved the discharge capacity and cycling stability of Li4Ti5O12. In particular, the coated Li4Ti5O12 with 20 wt% LPAN and 1% acetylene black (CB) reached 166.2 mAh g−1 at 10C. The performance improvement is a result of the graphene-like nanosheet conformal coating, which creates an electrically conductive network for the electrode.