The Polymer Society of Korea

Abstract

Despite the widespread adoption of lithium metal batteries, safety and sustainability remain major challenges. Solid polymer electrolytes (SPEs) offer a safer and more durable alternative, with advantages such as flexibility, thin-film processability, and mechanical stability. Crosslinked rubbery polymers with low glass transition temperatures are typically used to ensure high lithium-ion conductivity, strong interfacial adhesion, and mechanical integrity. However, their permanent crosslinks hinder recyclability. To address this, poly(β-amino ester) (PBAE)-based covalent adaptable networks (CANs) were developed as fully recyclable, catalyst-free, and highly adhesive SPEs. Their lithium-ion conductivity, dynamic bond exchange behavior, and adhesion were systematically investigated across different crosslinking densities. Additionally, the reprocessability of the electrolytes was demonstrated, and lithium salts within the network were recovered with high purity.