Sol–gel synthesis and electrochemical performance of Li4Ti5O12/graphene composite anode for lithium-ion batteries

Li4Ti5O12/graphene composite was prepared by a facile sol–gel method. The lattice structure and morphology of the composite were investigated by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The electrochemical performances of the electrodes have been investigated compared with the pristine Li4Ti5O12 synthesized by a similar route. The Li4Ti5O12/graphene composite presents a higher capacity and better cycling performance than Li4Ti5O12 at the cutoff of 2.5–1.0 V, especially at high current rate. The excellent electrochemical performance of Li4Ti5O12/graphene electrode could be attributed to the improvement of electronic conductivity from the graphene sheets. When discharged to 0 V, the Li4Ti5O12/graphene composite exhibited a quite high capacity over 274 mAh g−1 below 1.0 V, which was quite beneficial for not only the high energy density but also the safety characteristic of lithium-ion batteries.

► Li4Ti5O12/graphene composite is synthesized by a sol–gel method for the first time.
► The introduction of graphene can improve the capacity and cycling stability of Li4Ti5O12, especially at high current rates.
► Li4Ti5O12/graphene composite discharged to 0 V exhibits a quite high capacity of 274 mAh g−1 below 1.0 V.