The intermolecular interaction enables ordered ion transport in quasi-solid-state electrolyte for ultra-long life lithium-metal battery

Abstract

Composite gel polymer electrolytes (CGPEs) have received wide attention due to their great potential to improve the safety and cycling stability of lithium (Li) metal batteries. However, the poor interface compatibility between the filler and polymer in CGPEs severely hinders lithium-ion (Li+) pathways and limits cell performance. Herein, we propose an Al(EtO)3 nanowires framework that can trigger poly (ethylene glycol) diglycidyl ether (PEGDE) to undergo ring opening polymerization, thus inducing polymer tight combination on the surface of Al(EtO)3 nanowires framework and dividing the polymer matrix into mesh units, contributing to ordered Li+ transport and dendrite-free deposition on the metallic anode. Such a CGPE with highly conductive and interface compatibility facilitates a high-performance quasi-solid-state Li||Li cell with an excellent long-term cycling stability for over 3000 h without a short circuit and registers a high capacity of 146.9 mAh g−1 after 46 cycles at a mass loading of 6 mg cm−2. Solid-state nuclear magnetic technology clearly clarifies the transport path of lithium ions in Al(EtO)3-based gel polymer electrolyte (AGPE). The results open up a new way to improve the electrochemical performances of composite electrolyte and promote its commercial application process.