Spinel LiMn1.925M0.075O4 (M=Cr, Co) powders with small and uniform particle size were successfully synthesized by microwave-induced combustion. The LiMn1.925M0.075O4 (M = Cr, Co) samples were used as cathode materials for lithium-ion battery, which their discharge capacity and electrochemical characteristic properties were investigated in this study. The results revealed that The Li/LiMn1.925M0.075O4 (M = Cr, Co) cells showed lower capacity loss than Li/LiMn2O4 cell after 30 cycles. Moreover, Cr-substituted spinel exhibited a lower capacity loss than Co-substituted spinel. The initial capacity of LiMn2O4 and LiMn1.925M0.075O4 cells can be ranked as follows: LiMn2O4 > LiMn1.925Cr0.075O4 > LiMn1.925Co0.075O4. (c) 2006 Elsevier B.V. All rights reserved.