Preparation of submicrocrystal LiMn2O4 used Mn3O4 as precursor and its electrochemical performance for lithium ion battery

Spinel LiMn2O4 has been synthesized by solid state reaction with industrial grade Mn3O4 and Li2CO3 as precursors without purification, and its electrochemical performance for lithium ion battery has been investigated by CR2025 coin cell. The results of X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) images show that the size of LiMn2O4 particles grow up with increasing temperature of calcination, and the sample synthesized at 800 degrees C for 12 h has the best crystallinity with a submicron size. It can deliver initial capacity of 112.9 mA h/g with capacity retention ratio of 89.1% after 200 cycles at charge/discharge rate of 1 C. The results of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) also show that it has the highest electrochemical activity and lowest charge transfer impedance. (C) 2014 Elsevier B.V. All rights reserved.