Preparation of layer structured titanate Cs xTi 2− xFe xO 4 ( x=0.70) and application as cathode material in rechargeable lithium battery

Abstract

The layer structured titanate Cs x Ti 2− x Fe x O 4 ( x=0.70) with the lepidocrocite (γ-FeOOH) structure has been prepared in a solid state reaction using Cs 2CO 3, anatase type TiO 2 and α-Fe 2O 3 at 800 °C. Cs + in the interlayer space was ion exchanged with hydrated Li + in a LiNO 3 solution. The interlayer water was removed by heating at 180 °C in a vacuum. The resulting layer structured titanate Li 0.60H 0.04Cs 0.06Ti 1.30Fe 0.70O 4 was evaluated for use as the cathode in a rechargeable lithium battery. The theoretical capacity of the titanate is 106 mA h/g for the Fe 3+/Fe 2+ redox couple. The cathode exhibited discharge and charge capacities of 110 and 92 mA h/g for the first cycle in the voltage range of 1.5–4.2 V. The amounts of lithium intercalated and deintercalated in the titanate correspond to 0.73 and 0.61 of the formula unit.