Abstract Plain and cerium-doped LiNi0.5Co0.2Mn0.3O2 cathode materials were prepared via a combustion method, then graphene was coated onto the materials by a physical method. The results of x-ray diffraction, scanning… Click to show full abstract
Abstract Plain and cerium-doped LiNi0.5Co0.2Mn0.3O2 cathode materials were prepared via a combustion method, then graphene was coated onto the materials by a physical method. The results of x-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy confirmed the presence of a graphene coating layer on the LiNi0.497Ce0.003Co0.2Mn0.3O2 samples, the stratified structure and surface appearance of which were identical to those of LiNi0.5Co0.2Mn0.3O2. The 3 wt% graphene-coated LiNi0.497Ce0.003Co0.2Mn0.3O2 samples showed enhanced electrochemical performance with retention of 77.47% capacity over 50 cycles, compared with 72.02% for uncoated samples. Moreover, 3 wt% graphene-coated LiNi0.497Ce0.003Co0.2Mn0.3O2 sustained superior discharge-specific capacity and better stability at high current densities such as 2C. Cation disordering was decreased by inhibition of the side effects inherent in charge-discharge processes, which gave rise to more stable structures. These enhancements in the electrochemical performance of LiNi0.5Co0.2Mn0.3O2 can be attributed to cerium doping and graphene coating.
               
Click one of the above tabs to view related content.