Study and Property Characterization of LiMn2O4 Synthesized from Octahedral Mn3O4

Abstract

The structure of Mn3O4 with an octahedron structure was similar to that of LiMn2O4, and the lithium manganate prepared with it had good electrochemical performance. During the preparation of octahedron Mn3O4, the effects of the pH regulator, temperature, and reaction pH on its morphology, specific surface area, and other properties were studied in this paper. LiMn2O4 was prepared from Octahedron Mn3O4 obtained by using better technology. The effects of calcination time and temperature on the physicochemical and electrochemical properties of LiMn2O4 were studied. The research results indicated that the optimal synthesis conditions for Mn3O4 were as follows: ammonia water was used as a pH regulator and complexing agent, reaction pH was 8, reaction temperature was 80 °C, reaction time was 12 h, and oxygen flow rate was 3 L∙min−1. The LiMn2O4 synthesized had a good octahedron morphology when the calcination temperature was 800 °C and the calcination time was 10 h. The first discharge-specific capacity was 121.9 mAh∙g−1 at a current density of 0.2 C, the discharge-specific capacity was 114.1 mAh∙g−1 after 100 cycles, and the capacity retention rate was 93.6%. Therefore, the lithium manganate prepared by using octahedron manganous oxide had good electrochemical reversibility and a good application prospect.