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

Abstract

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 2.5–1.0V, 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 0V, the Li4Ti5O12/graphene composite exhibited a quite high capacity over 274mAhg−1 below 1.0V, which was quite beneficial for not only the high energy density but also the safety characteristic of lithium-ion batteries.