LiMn 1.95M 0.05O 4 (M: Al, Co, Fe, Ni, Y) cathode materials prepared by combustion synthesis

Abstract

Spinel LiMn 1.95M 0.05O 4 (M: Al, Co, Fe, Ni, or Y) is prepared by a combustion synthesis, which is a simple, rapid and cost-effective process for obtaining oxide powders. The spinel is obtained by combustion of lithium hydroxide, manganese nitrate, M-nitrates, and urea at about 280°C for 1 min. Well-defined spinel LiMn 1.95M 0.05O 4 was obtained by further heat-treatment at 800°C for 10 h. The synthesized LiMn 1.95M 0.05O 4 shows lower initial capacities, viz. 90–132 mAh/g than undoped LiMn 2O 4. The latter has an initial capacity of 146 mAh/g which fades to 100 mAh/g with cycling. On the other hand, LiMn 1.95Co 0.05O 4, LiMn 1.95Ni 0.05O 4, and LiMn 1.95Y 0.05O 4 display better cycleability than LiMn 2O 4.