Porous Li4Ti5O12/ Reduced Graphene Oxide Anode Materials with Enhanced Rate Capability and Cyclability

Abstract

Li4Ti5O12 (LTO) is one of the most promising anode materials for lithium-ion batteries. Besides its advantages of near-zero volume change, solid electrolyte interface free, and high thermal stability, further improvement of its performance is hindered by the intrinsic electronic insulating property of LTO. Graphene is an excellent additive to improve electrode performance due to its high conductivity, large surface area and chemical stability. In this study, porous LTO/reduced graphen oxide (rGO) composite thin films were prepared by electrostatic spray deposition (ESD). Graphen oxide sheets used in precursor were readily reduced to rGO during the ESD deposition. The electrochemical performance was characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge. Our results reveal that the LTO electrodes exhibit high rate capability and long cycle life. In the potential range of 0.05-3 V, the LTO electrode delivers reversible specific capacity of 274，257, 240, 202, 158 and 106 mAh g-1 at different current rates of 0.5 C, 1 C, 2 C, 5 C, 10 C and 20 C, respectively. After high C rate test, the electrode was tested at 2 C for 100 cycles. No capacity decay was observed even after testing at harsh condition. Detailed results will be presented in the meeting.