A remarkably high lithium storage capability, high rate performance, and cyclability were observed in nanometer-sized rutile TiO2 electrode at room temperature. The Li insertion ratio, Li/Ti, can be well above 1 in rutile nano-electrode at the first discharge cycled at 0.05 A/g, and about 0.6-0.7 Li can be reversibly cycled. After 100 cycles the discharge capacities of an ultrafine rutile electrode are still of 132 and 118 mAh/g when being cycled at 5 and 10 A/g, respectively. Our results suggest that nanometer-sized rutile can be a promising anode material for lithium-ion batteries, especially for high power and high energy density use. (c) 2007 The Electrochemical Society.