Lithium insertion into spinel Li(4)Ti(5)O(12) incorporated with rutile TiO(2) was investigated in order to clarify the redox mechanism responsible for the first plateau at 1.5 V vs. Li/Li(+). Spherical Li(4)Ti(5)O(12) powders with an average diameter of 2-3 mu m can be achieved by spray drying followed by sintering process. The Li/Ti molar ratio in the precursor is selected as the factor for preparing spine! Li(4)Ti(5)O(12) powders with different concentrations of rutile TiO(2). The specific capacity from the first plateau at 1.5 V contributes to the major portion in the overall capacity. The rutile TiO(2) in spinel Li(4)Ti(5)O(12) anodes tends to improve the specific capacity at the first plateau. This can be attributed to two possible reasons: (i) rutile TiO(2) provides an additional number of sites (i.e., oxygen octahedral vacancy in rutile TiO(2)) for the Li insertion, and (ii) less amount of residual Li oxides results in high electronic conductivity. The Li(4)Ti(5)O(12) anodes display high rate capability with low irreversible capacity, indicating good reversibility of insertion/de-insertion of Li ions. The results presented in this work show unambiguously that the presence of rutile TiO(2) in spinel Li(4)Ti(5)O(12) has a positive effect on the performance promotion of Li(4)Ti(5)O(12) anodes. (C) 2011 Elsevier B.V. All rights reserved.