Enhancing the electrochemical performances of LiNi0.5Mn1.5O4 by Co3O4 surface coating

Abstract A Co 3 O 4 coating is formed on the surface of LiNi 0.5 Mn 1.5 O 4 particles via an ethanol mediated precipitation method. The existence of the uniform Co 3 O 4 coating is clearly observed by scanning electron microscopy and transmission electron microscopy. The results of electrochemical performance testing prove that the Co 3 O 4 coating can greatly enhance the cycling stability and rate performance of LiNi 0.5 Mn 1.5 O 4 . The optimal sample 5% Co 3 O 4 -coated LiNi 0.5 Mn 1.5 O 4 delivers a discharge capacity 126 mAh g −1 at 1 C rate with a capacity retention 96.8% after 300 cycles and a high discharge capacity 97.5 mAh g −1 at 10 C rate. The causes to the improvement are discussed based on elemental analysis, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy.