Nano-sized TiO2 with an anatase phase is prepared by hydrolysis of titanium tetraisopropoxide in pure water. Samples are characterized by transmission electron microscopy (TEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). TiO2 nanoparticles experienced two processes of phase transition, i.e., amorphous to anatase and anatase to rutile, over the temperature range from 60 to 800 degrees C. The electrochemical properties of Li+ ion insertion in nano-sized TiO2 (anatase) electrodes is studied by voltammetry. The diffusion-limited insertion and extraction of Li ions in the anatase lattice within a region near the peak potential are dominating. The anatase TiO2 nanoparticles exhibit a large initial electrochemical lithium insertion capacity of 195 mA h g(-1), good reversibility, and cyclic stability. (c) 2004 Elsevier B.V. All rights reserved.