Preparation and Characterization of LiMn_2-xMg_xO₄ by Low-Temperature Flameless Solution Combustion Synthesis

Abstract

The spinel Mg-doped LiMn2-xMgxO4（0≤x≤0.10）lithium ion cathode material was prepared by LiNO3, Mn(Ac)2.4H2O and Mg(Ac)2.4H2O by a low-temperature flameless solution combustion at 400°C, and HNO3 was used as oxidant. The results showed that the crystallinity of prepared material was superior to the pure LiMn2O4, and this method was better than traditional solid-state method. The particle sizes of the Mg-doped spinel LiMn2-xMgxO4 decreased with the increase of Mg doping, and the particle sizes were 50 to 90 nm; the crystal lattice interface was clear. The original capacities of Mg-doped were lower than that of undoped LiMn2O4 (109.2 mAh/g) excepts for x(Mg)=0.04, original capacity of which was 128mAh/g. However, the rentions of all the doped spinels were higher than that of undoped spinel.