Organosilicon-group-derived silica-ionogel electrolyte for lithium ion batteries

In order to avoid leakage problem caused by liquid electrolyte, a new ionogel electrolyte was developed by in situ immobilizing organosilicon-functionalized ionic liquid within a nanoporous silica matrix. The ionic liquid evenly coats on the surface of porous silica and fills in the silica framework pores with no strong chemical interaction. The ionogel electrolyte has the dual advantages of a silica solid support and a wide electrochemical stability window of ionic liquid (4.87 V vs. Li⁺/Li). The half-cells assembled with this electrolyte and LiFePO₄ electrode have excellent performance at room temperature and 60 °C. The Li/SiO₂-IGE/LiFePO₄ cell displays a discharge capacity of 129.1 mAh·g⁻¹ after 200 charge/discharge cycles at room temperature.