Micro-spherical particle of MnCO3 has been successfully synthesized in CTAB-C8H18-C4H9OH-H2O micro-emulsion system. Mn2O3 decomposed from the MnCO3 is mixed with Li2CO3 and sintered at 800 degrees C for 12 h, and the pure spine! LiMn2O4 in sub-micrometer size is obtained. The LiMn2O4 has initial discharge specific capacity of 124 mAh g(-1) at discharge current of 120 mA g(-1) between 3 and 4.2V. and retains 118 mAh g-1 after 110 cycles. High-rate capability test shows that even at a current density of 16C. capacity about 103 mAh g(-1) is delivered, whose power is 57 times of that at 0.2C. The capacity loss rate at 55 degrees C is 0.27% per cycle. (C) 2009 Elsevier Ltd. All rights reserved.