Enhanced electrochemical performances of Li1.2Ni0.2Mn0.6O2 cathode materials by coating LiAlO2 for lithium-ion batteries

摘要

LiAlO2-coated Li1.2Ni0.2Mn0.6O2 lithium-rich layered oxide was prepared and investigated as cathode material for lithium-ion batteries. X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) analyses revealed that a uniform LiAlO2 layer was coated on the surface of Li1.2Ni0.2Mn0.6O2 particles. The LiAlO2-coated Li1.2Ni0.2Mn0.6O2 exhibited a great improvement on electrochemical performance, especially for its excellent cycling stability both at room and elevated temperature, compared to the pristine Li1.2Ni0.2Mn0.6O2. In addition, the LiAlO2-coated Li1.2Ni0.2Mn0.6O2 showed obviously enhanced rate capability (162.6 mA h g(-1) at 2 C and 112.3 mA h g(-1) at 5 C) and suppressed the voltage fading during long-term and high-rate cycling. Based on these results, LiAlO2 coating would be a promising method to improve the electrochemical performance of lithium-rich layered oxides. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.