Triple synergy of anion immobilization continuous channels and segmental activation for high-performance polymer solid electrolytes

Achieving both high ionic conductivity and a high Li + transference number at room temperature remains a critical challenge for polymer solid electrolytes due to the intrinsic trade-off between segmental dynamics and ion coupling. In this work, we address this issue by incorporating ZIF-67 and dealkaline lignin (DL) into the PEO matrix. ZIF-67 exposes abundant Co 2+ Lewis acid sites that immobilize TFSI − anions, while its ordered porous framework, together with polymer-filler interfaces, creates low-barrier Li + migration pathways. DL further promotes salt dissociation and enhances chain flexibility through hydrogen bonding. This synergistic design reduces PEO crystallinity, anchors anions, and maintains uninterrupted ion channels, collectively enabling fast Li + conduction. The optimized electrolyte achieves a room-temperature conductivity of 1.7 × 10 −4 S cm −1 , a Li + transference number of 0.75, and a wide 5.10 V window. LiFePO 4 /Li and NCM811/Li cells deliver 159.12 mAh g −1 at 0.1C and 190.74 mAh g −1 at 0.5C, respectively. Beyond experimental validation, this work elucidates the triple synergy of anion immobilization, continuous channel transport, and segmental activation, offering a new design paradigm for advanced polymer solid electrolytes.