Improvement in electrochemical performance of calcined LiNi0.5Mn1.5O4/GO

• LiNi0.5Mn1.5O4/graphene composite materials were successfully synthesized by calcining LiNi0.5Mn1.5O4/GO.
• LiNi0.5Mn1.5O4/graphene composite materials presented a thin, compact and uniform coating layer.
• LiNi0.5Mn1.5O4/graphene composite materials gave a better electrochemical performance, especially cyclic performance.
• This method is suitable for industrial production.

This study aimed to use the excellent properties of graphene as coating for the cathode material LiNi0.5Mn1.5O4. In this work, we added a calcination process based on the graphene oxide coating process from previous studies to obtain the calcined LiNi0.5Mn1.5O4/GO composite. The morphology and structure of the prepared samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Their performance as electrodes of lithium-ion battery was investigated by charge/discharge and cycle performance tests. The calcined LiNi0.5Mn1.5O4/GO composite obtained by the improved method presented a thin, compact, and uniform coating layer and improved the electrochemical performances of LiNi0.5Mn1.5O4 with no effect on the crystal structure. The calcined LiNi0.5Mn1.5O4/GO could deliver a capacity of 131.2 mAh g− 1, which was approximately 10 mAh g− 1 larger than that of LiNi0.5Mn1.5O4. After 280 cycles at 1 C rate, the calcined LiNi0.5Mn1.5O4/GO could still deliver a reversible capacity of 123.2 mAh g− 1, retaining 94% of its initial reversible capacity.