Precipitation synthesis and enhanced electrochemical performance of graphene-modified LiMn2O4 for lithium-ion batteries

Abstract

The graphene-modified LiMn2O4 cathode material was synthesized by precipitation method. X-ray diffraction (XRD), scanning electron microscopy (SEM), and fourier transform infrared (FITR) showed LiMn2O4 had been successfully combined with the graphene. The charge and discharge tests and electrochemical impedance spectroscopy (EIS) were used to study electrochemical properties of as-synthesized material. The results showed that the electrochemical properties of the graphene oxide–supported LiMn2O4 were superior to that of the LiMn2O4 material. The initial discharge capacity of the graphene-modified LiMn2O4 material reached 127 mAh g−1. After 100 cycles, it still had a capacity retention rate of 96.2%. Enhanced electrochemical performance of graphene-supported LiMn2O4 could be attributed to the establishment of fast Li+ channels and structural stability after coating LiMn2O4 with the graphene.