Electrochemical properties of Si-Fe incorporated SiOx/graphite base anode materials

To solve the major defects of SiOx-based anode materials, composite materials with different Si-Fe content and SnO2 were deliberately prepared via a tandem strategy involving mechanical ball milling, spray drying, and high-temperature pyrolysis in this paper. Furthermore, the phase structures, microscopic morphologies, and electrochemical properties of as-obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), and galvanostatic charge-discharge test system. The electrochemical results show that the composite containing a mass fraction of 5% Si-Fe possesses a relatively good comprehensive electrochemical performance with a charging capacity of 443.4 mAh center dot g(-1) and the first Coulombic efficiency of 75.2%. After 310 cycles, the charging capacity still retained 369.1 mAh center dot g(-1), and the capacity retention rate was up to 81.0%. Meanwhile, the lithium diffusion rate is remarkably improved after Si-Fe incorporation.