Synthesis and electrochemical performance of LiFeSiO/C cathode material using ascorbic acid as an additive.

Carbon-coated LiFeSiO composite (LFS/C-AA) was synthesized via a refluxing-assisted solid-state reaction by using ascorbic acid as additive and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, galvanostatic charge/discharge measurements, and electrochemical impedance spectra (EIS) tests. The results show that ascorbic acid can to some extent prohibit the oxidation of Fe during the synthesis process, and the pyrolytic carbon from ascorbic acid shows higher electronic conductivity and improves the degree of graphitization of residual carbon in the LFS/C-AA composite. Compared with LFS/C prepared without ascorbic acid, LFS/C-AA displays better electrochemical performance. The desirable property is attributed to the reduced particle size, the enhanced electronic conductivity, and the improved diffusion coefficient of lithium ions. [ABSTRACT FROM AUTHOR]