Effect of Temperature on LiMn₂O₄ Prepared by Molten-Salt Combustion Synthesis

Abstract

Spinel LiMn2O4 was prepared by a molten-salt combustion synthesis using eutectic acetate salts as starting materials without any additional molten-salt at 400°C, 500°C, 600°C and 700°C for 3h. The experimental results show that the main phase of the produts is spinel LiMn2O4, and the impurities are Mn2O3 or Mn3O4. It has been found that elevated temperature was easy to generate Mn3O4, and low temperature was easy to generate Mn2O3. The product prepared at 600 °C is single phase LiMn2O4 and has good crystallinity. With increasing combustion reaction temperature, the particle sizes of the products were decreased. The product prepared at 600 °C has the highest initial specific capacity of 116.5 mAh•g-1 at 0.2C, the capacity retention was only 77.2% after 50 cycles.