An Ion-Regulating Polymer Electrolyte With Zn Affinity for Stable Zinc Batteries

While polymer electrolytes offer a promising path to suppress dendrite growth and side reactions in aqueous zinc-ion batteries, their implementation often compromises ion transport kinetics and interfacial stability. Here, we report an ion-regulating copolymer electrolyte, poly(4-acryloylmorpholine)-co-poly(3-sulfopropyldimethyl-3-methacrylamidopropylammonium inner salt), engineered through a facile one-pot synthesis. This molecularly designed architecture combines multi-dentate zinc-binding sites with dynamic zwitterionic channels, enabling simultaneous anion confinement and rapid zinc-ion transport. The copolymer electrolyte promotes uniform ion flux and dense zinc deposition while maintaining intimate electrode contact, effectively eliminating dendrite formation and interfacial degradation. Symmetric Zn||Zn cells achieve excellent cycling stability over 1400 h with minimal polarization (∼110 mV) at 0.5 mA cm –2 . When integrated with V 2 O 5 cathodes, full cells exhibit outstanding reversibility, rate capability, and cycling durability. This work demonstrates a rational electrolyte design strategy that synchronizes bulk and interfacial ion regulation, providing a viable platform for high-performance, long-lived zinc batteries.