A new high ionic conductive gel polymer electrolyte enables highly stable quasi-solid-state lithium sulfur battery

Abstract

Abstract Solid-state lithium battery is regarded as high safety and high energy density next-generation energy storage device, but its poor lithium ionic conductivity severely limits its practical application. To address above issues, we report a new super-high ionic conductive gel polymer (SHGP) electrolyte (2.2 × 10–3 S cm–1 at 60 °C and 0.75 × 10–3 S cm–1 at 30 °C), which are significant characteristics for greatly improved quasi-solid-state lithium sulfur battery performance. Moreover, the SHGP electrolyte exhibited strong adsorptivity to lithium polysulfides as the polar functional groups in the SHGP electrolyte through chemical adsorption, leading to the suppressed shuttle effect, which was theoretically confirmed by density functional theory (DFT) calculations, molecular dynamics (MD) simulations and experimentally verified by in-situ UV/Vis results. Such high ionic polymer electrolyte enables a greatly improved specific capacity of 950 mAh g−1 at 0.2 C and outstanding cycling performance for 400 cycles at 1.5 C, which is far beyond that of conventional poly (ethylene oxide) based quasi-solid-state battery.