Synthesis, Characterization and Electrochemical Properties of Li<sub>1+x</sub>Mn<sub>2</sub>O<sub>4</sub> Spinels Prepared by Solution Combustion Synthesis

Abstract

Li1+xMn2O4 prepared by solution combustion synthesis method has a strong exothermic peak at 282.1 °C, which is believed that the reaction of LiNO3, LiAc2•2H2O with Mn(NO3)2 and MnAc2•4H2O occurs in this region. So products were calcined at 500 °C would got fine crystalline. Pure phase LiMn2O4 can be prepared with x(Li)=0.16 and 0.24 without impurity. Li-rich samples for x(Li)=0.16 and 0.24 has nanoparticles of which the surface area will be more and can lead to better electrode performance. The initial discharge capacity of Li1.16Mn2O4 was the highest of 116.4mAh•g-1, with a 15 % loss of the initial capacity after 40 cycles, which is much better than bare LiMn2O4. Excess Li+ is beneficial to formation of pure phase of spinel LiMn2O4 and Li1.16Mn2O4 has best electrochemical performance in the method of solution combustion synthesis.