Preparation of particulate Li4Ti5O12 having excellent characteristics as an electrode active material for power storage cells

In recent years, lithium secondary batteries have been widely utilized as a power source for mobile electronics, but modifications are required to apply this type of battery to motor vehicles or energy storage purposes. Although the excellent cycle characteristics of lithium titanate have been verified for small cells, the high rate characteristics of this material should be improved if it is used as an active material in large batteries. The authors prepared very fine particulates of lithium titanate having an average size of 0.7 μm. The prepared lithium titanate shows superior high rate characteristics, as well as excellent cycle characteristics. A high capacity maintenance ratio of 99% was achieved at 1 C and 25 °C after the 100th cycle. Taking the discharge capacity at 0.15 C, that at 10 C was 86% at 25 °C, while that at 50 °C was 96%.