Improved electrochemical performance of Li4Ti5O12 with a variable amount of graphene as a conductive agent for rechargeable lithium-ion batteries by solvothermal method

We report on the solvothermal preparation of pure Li4Ti5O12 and Li4Ti5O12/graphene (15 wt% and 30 wt%) nanocomposites anode for high-performance lithium-ion batteries. Structure and morphology studies of the nanocomposites by X-ray diffraction, field-emission scanning electron microscopy and field-emission transmission electron microscopy reveal Li4Ti5O12 nanoparticles embedded onto the graphene nanosheets. On comparison to pure spinel Li4Ti5O12, the electrochemical performances of the Li4Ti5O12/graphene nanocomposites indicate higher capacities and enhanced cycle performances within the voltage domain of 1.0–2.5 V, under current rates as high as 10.4 C. The production of phase pure Li4Ti5O12 nanoparticles ensures the short ion-diffusion paths while the presence of graphene facilitates improved structural network and hence enhanced electronic transport in the prepared nanocomposites. These factors eventually amount to impressive electrochemical properties.