A low-temperature reaction route to high rate and high capacity LiNi0.5Mn1.5O4

New applications of lithium ion batteries in hybrid electric vehicles require high electrochemical performance such as improved power density. High crystalline submicron-size LiNi0.5Mn1.5O4 with high capacity and high rate capability was explored in this work through a low-temperature solid-state reaction route. Samples were characterized by thermal gravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and cell measurements. It is found that LiNi0.5Mn1.5O4 thus obtained has a cubic spine] structure, which can be indexed in a space group of Fd3m with a disordering distribution of Ni. The particle size is about 200 nm. Electrochemical tests demonstrated that the as-prepared LiNi0.5Mn1.5O4 possesses high capacity and excellent rate capability. When discharged at a rate as high as of 8C, the as-prepared LiNi0.5M1.5O4 powders can still deliver a capacity of 110 mAh g(-1), which shows to be a potential cathode material for high power batteries. (c) 2007 Elsevier B.V All rights reserved.