Design of organic-inorganic hybrid ion-gel electrolytes composed of borosilicate and allylimidazolium type ionic liquids

Research towards the design of novel electrolytes for the development of safer and efficient Li-ion batteries has gained widespread momentum in recent years. Design of novel borosilicate glass/ionic liquid hybrid type electrolyte was undertaken. Organic-inorganic hybrids have the dual advantages of high ionic conductivity due to the organic component and high thermal stability due to the inorganic components. In the present work, an in-situ sol-gel method using alkoxysilanes and alkoxyboranes was carried out, in the presence of low viscous ionic liquids. This resulted in the formation of highly homogenous organic-inorganic hybrids. A low viscous diallylimidazolium type ionic liquid was employed as the organic component. Arrhenius plots evinced constant temperature dependence of ionic conductivity. A maximum ionic conductivity of 2.0 mS cm−1 at 51 °C, was observed among the prepared hybrids. LiPF6 based hybrids showed higher ionic conductivity due to larger phase separation order of organic and inorganic components which enables better connection of ion-conductive organic components. On the other hand, LiTFSA based hybrids were highly homogenous and exhibited much improved thermal stability.