Particle Size Dependence of TiO2 Electrodes in Rechargeable Lithium Battery

Particle size effects in five anatase TiO2 pellet electrodes with different particle sizes and surface areas were studied by XRD analysis, chronopotentiometry and chronoamperometry in Li/LiN(CF3SO2) + EC:DME/TiO2 cells. Nanosized TiO2 electrodes showed by 22% larger storage capacity, 50% lower overvoltage loss at the same current density, and 75% higher charge density for a given time thanmicrosized ones; electric storage capacity enhances more rapidly with decreasing particle size and increasing surface area in a nanoscale region than in a microscale region. The particle size dependence may be explained by surface morphology of electrodes and existence of structural defects or distortion in the surface layer of TiO2 nanosized particles.