Interpenetrating Double-Network Gel Polymer Electrolyte Enabling Mechanically Adaptive Fiber-Shaped Zinc-Ion Hybrid Supercapacitors

Abstract

The development of flexible and wearable electronics necessitates energy-storage systems that combine high electrochemical performance with mechanical adaptability. However, conventional gel polymer electrolytes (GPEs) struggle to simultaneously achieve high ionic conductivity, sufficient mechanical strength, effective deformation recovery, and stable electrode/electrolyte interfaces. Herein, we report a double-network GPE (PACAS) comprising a dynamic physically cross-linked amylopectin/carboxymethyl cellulose network interpenetrated with a mechanically robust covalently cross-linked P(AM-co-DMAPS) network. The zwitterionic DMAPS units facilitate homogeneous Zn2+ distribution, enhance ionic conductivity through coordination interactions, and regulate local electrostatic environments. The optimized PACAS-8:2 GPE exhibits an ionic conductivity of 11.22 mS cm–1 and comprehensive mechanical adaptability, including stretchability, flexibility under bending and twisting, deformation recoverability, and self-healing capability, while its favorable self-extinguishing behavior contributes to enhanced safety in flexible energy-storage applications. When assembled into fiber-shaped zinc-ion hybrid supercapacitors (ZIHSs) with PPy@SSY positive electrodes, the device operates stably within 0–1.6 V and delivers a specific capacitance of 114.314 F g–1 at 0.1 A g–1, corresponding to an energy density of 38.764 Wh kg–1 and a power density of 68.59 W kg–1. The device demonstrates excellent rate capability, favorable cycling stability over 600 cycles with near-100% Coulombic efficiency, and robust electrochemical performance under bending radii down to 14 mm. Series/parallel integrations of fiber-shaped ZIHS devices successfully power LED arrays and electronic timers, highlighting the substantial practical potential of this mechanically adaptive GPE for next-generation wearable and portable electronic applications.