SIMPLE AND LOW-COST SYNTHESIS OF LI2FESIO4 CATHODE MATERIALS BY MECHANICAL ACTIVATION USING A Fe3+ PRECURSOR

An easy and low-cost synthesis of monoclinic Li2FeSiO4 based on a carbothermal process and a short-time preliminary milling of a reactant mixture in a planetary mill was investigated. Monoclinic Li2FeSiO4/C is prepared using Fe3+ (Fe2O3) as a precursor. For this purpose, commercial hematite and one obtained through a green route were used. This material is studied and compared with Li2FeSiO4 obtained using Fe2+ (FeC2O4·2H2O) as a precursor. In all cases, citric acid was used as a reducing agent and as an in situ conductive additive. Mössbauer spectroscopy was used as the central technique in this study.