LiCo 1− xAl xO 2 (0 ≤ x ≤ 0.05) cathode powders prepared from the nanosized Co 1− xAl xO y precursor powders

Abstract

Fine LiCo 1– x Al x O 2 (0 ≤ x ≤ 0.05) cathode powders were prepared by the solid-state reaction method using nanosized Co 1− x Al x O y (0 ≤ x ≤ 0.05) precursor powders with various concentrations of aluminum used as the dopant. The Co 1− x Al x O y precursor powders prepared by spray pyrolysis had nanometer size and a regular morphology after post-treatment at 800 °C. The aluminum dopant decreased the mean particle sizes of the Co 1− x Al x O y precursor powders and LiCo 1– x Al x O 2 cathode powders. The mean particle sizes of the LiCoO 2 and LiCo 0.95Al 0.05O 2 cathode powders were 1.1 and 0.52 μm, respectively. The initial discharge capacities of the LiCoO 2 and LiCo 0.99Al 0.01O 2 cathode powders were 151 and 161 mAh g −1, respectively. The discharge capacity of the LiCoO 2 cathode powders after the 50th cycle was 90% of their maximum discharge capacity. However, the discharge capacities of the LiCo 0.99Al 0.01O 2, LiCo 0.97Al 0.03O 2, and LiCo 0.95Al 0.05O 2 cathode powders after the 50th cycle were 91, 84, and 82%, respectively, of their respective maximum discharge capacities.