Graphene-Enhanced FePO4 Composites with Superior Electrochemical Performance for Lithium-Ion Batteries

Abstract

In this study, we successfully synthesized olivine-type FePO4 via an in situ oxidation method and further developed two composite cathode materials (o-FePO4-1/GR-1 and o-FePO4-1/GR-2) by incorporating graphene. The composites were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS), revealing a three-dimensional porous layered structure with an enhanced surface area and strong interaction between FePO4 nanoparticles and graphene layers. Electrochemical tests demonstrated that the composite electrodes exhibited significantly improved performance compared to pristine FePO4, with discharge capacities of 147 mAh g−1 at 1C and 163 mAh g−1 at 0.1C for o-FePO4-1/GR-2, approaching the level of LiFePO4. The incorporation of graphene effectively enhanced the electrochemical reaction kinetics, highlighting the innovation of our method in developing high-performance cathode materials for lithium-ion batteries.