Beyond PEO: Redesigning Polymer Electrolytes for Scalable All-Solid-State Batteries

All-solid-state batteries (ASSBs) are promising for safer, high-energy-density energy storage. Polymer electrolytes are attractive because of their synthetic versatility, favorable interfacial contact, and compatibility with scalable manufacturing. However, their development has been dominated by polyethylene oxide (PEO), whose limited salt dissociation, crystallinity, segmental-motion-dependent Li⁺ transport, and low Li⁺ transference number impose intrinsic constraints.

This presentation introduces a “Beyond PEO” framework that redefines polymer electrolytes as engineered ion-transport architectures rather than passive ion-solvating matrices. By controlling entropy, supramolecular organization, and dynamic bonding, this approach regulates ionic conduction, mechanical resilience, and electrochemical integration.

Conflicting-entropy-driven zwitterionic polymer electrolytes promote salt dissociation and establish organized Li⁺-transport pathways decoupled from conventional segmental relaxation, enabling pouch-type ASSBs to operate at ambient temperature. Ionic dimer elastomers use dynamic ionic crosslinking to combine ion conduction with mechanical robustness. Monomer-in-salt polymer catholytes extend these principles to electrode manufacturing. Through in situ polymerization, they form solvent-free, compositionally uniform, and ionically percolated catholyte networks for dry-processed Ah-class pouch cells. Despite their different molecular designs, these systems share a common objective: to decouple Li⁺ transport from the classical PEO paradigm, direct ion transport through designed pathways, and embed manufacturability into materials design. Their compatibility with established lithium-ion battery processes also supports stable operation under practically relevant low stack pressure.

These studies position“Beyond PEO” as a materials-design framework for robust and scalable polymer-based ASSBs.