A facile method to prepare hybrid LiNi0.5Mn1.5O4/C with enhanced rate performance

The hybrid LiNi0.5Mn1.5O4/C cathode material is prepared with a facile method of pre-mixing and post-calcination treatment for enhancing the rate performance. The physical and electrochemical properties are discussed through X-ray diffraction (XRD), transmission electron microscopy (TEM), charge-discharge measurements in test cells and electrochemical impedance spectroscopy (EIS). The results show that the LiNi0.5Mn1.5O4 particle can be partially surrounded and interconnected with each other by carbon black particles, therefore the electronic conductivity can be remarkably improved by over 5 times without degrading the spinel structure. The LiNi0.5Mn1.5O4/C composite exhibits enhanced rate capability together with cycling performance compared to LiNi0.5Mn1.5O4. EIS confirms that the significantly improved electrochemical property is due to the suppression of surface resistance and the enhanced electronic conductivity. (C) 2011 Elsevier B.V. All rights reserved.