Physical properties and electrochemical performance of LiNi0.5Mn1.5O4 cathode material prepared by a coprecipitation method

LiNi0.5Mn1.5O4 spinel has been prepared by a coprecipitation method, and the effects of calcination temperature on the physical properties and electrochemical performance of the samples have been investigated. The results of XRD and scanning electron microscopy (SEM) showed that as calcination temperature increases, the crystallinity of the samples is improved, and their grain sizes obviously increase. It was found that the samples calcined at relatively high temperatures present large initial discharge capacity (> 125 mAhg(-1)) and excellent cycling stability with a capacity retention rate larger than 95% after 100 cycles at 1 degrees C and 25 degrees C. This probably derives from their higher crystallinity and larger grain sizes. (C) 2007 Elsevier B.V. All rights reserved.