Sol-gel synthesis of Li2MnSiO4/C nanocomposite with improved electrochemical performance for lithium-ion batteries

In recent years, modifying anode materials surfaces of Li₂MnSiO₄ become a popular pursuit. This paper reveals a fast sol-gel process that the Li₂MnSiO₄ in situ coated with carbon membrane prepared using liquid polyacrylonitrile (LPAN) as the carbon source. The structure and micro-morphology of the as-prepared Li₂MnSiO₄ and Li₂MnSiO₄/C nanocomposite were characterized by thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The electrochemical properties of the as-prepared Li₂MnSiO₄ and Li₂MnSiO₄/C nanocomposite were evaluated cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). The results showed that Li₂MnSiO₄/C have a good electrochemical performance and the Li₂MnSiO₄ coated with a calcined 10 wt% LPAN carbon membrane insitu reached 225.6 mAh g^-1 at room temperature. It is more than one electron (1.36Li⁺) transfer during the intercalation/deintercalation process, corresponding to 68% of its theoretical two-electron redox capacity (330 mAh g^-1).