Properties of Al Doped $LiMn_2O_4$ Powders Prepared by Spray Pyrolysis Process

Al doped cathode powders with fine size were synthesized by an ultrasonic spray pyrolysis method from the spray solution with citric acid and ethylene glycol. The as-prepared powders with spherical shape, porous structure and micron size turned into powders with micron size and regular morphology after post-treatment above 800. The powders had low initial discharge capacity of 94 mAh/g at a posttreatment temperature of . As the post-temperature increased from to , the initial discharge capacities of the powders changed from 103 to 117 mAh/g. The powders had the maximum discharge capacity at a post-treatment temperature of . However, the powders post-treated at a temperature of 900 had the good cycle properties. The discharge capacities of the powders dropped from 107 to 100 mAh/g (93% capacity retention) by the 70th cycle at a current density of 0.1 C.