In this study, spinel Li4Ti5-xAlxO12 (x = 0, 0.05) materials were successfully synthesized by a simple and facile sol-gel process. The characteristics of the as-prepared Li4Ti5-xAlxO12 (x = 0, 0.05) were examined by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and scanning electronic microscopy, while the electrochemical performances including charge/discharge test, cyclic voltammetry, and electrochemical impedance spectroscopy were also investigated. Li4Ti4,95Al0.05O12 electrode demonstrated the superior initial discharge capacity and rate capability to Li4Ti5O12 electrode cycled between 1.0 and 2.5 V or between 0 and 2.5 V. The enhanced rate capability can be attributed to the higher Li+ diffusivity and lower charge-transfer resistance due to the substitution of Al3+ for Ti4+. Moreover, when both electrodes discharged to 0 V. the reversible capacities were further increased 50 mAh g(-1) with excellent cycling stability and almost no irreversible capability was observed during cycling. (C) 2012 Elsevier Ltd. All rights reserved.