Electrostatic-interaction-tailored PAM-PA-ChCl deep-eutectic gel electrolyte for high-performance zinc‑iodine batteries

Tailored electrostatic interactions in a deep eutectic gel electrolyte suppress Zn dendrites and polyiodide shuttling. • Choline cations guide uniform Zn flux while phosphate anions repel polyiodides. • The electrolyte enables a 4000 h Zn anode lifespan and 19,000 cycles for full Zn I 2 batteries. Aqueous zinc‑iodine batteries (AZIBs) represent a highly attractive technology for large-scale energy storage, yet their practical deployment is severely hindered by the concurrent challenges of zinc dendrite growth, parasitic side reactions, and the polyiodide shuttle effect. Herein, we design an electrostatic-interaction-tailored polyacrylamide-phytic acid-choline chloride (PAM-PA-ChCl) deep-eutectic gel electrolyte (DEGE) to fundamentally manipulate the interfacial microenvironment. Within this DEGE, the electrostatic shielding of choline cations (Ch + ) effectively homogenizes the local Zn 2+ flux to suppress dendrite proliferation, while the coordination between PA and Zn 2+ optimizes deposition kinetics. Concurrently, the robust electrostatic repulsion from the phosphate anions of PA blocks polyiodide crossover, thereby eliminating the shuttle effect. Benefiting from this sophisticatedly tailored microenvironment, the DEGE enables an exceptionally stable zinc stripping/plating lifespan of up to 4000 h at 1 mA cm −2 . Remarkably, the assembled AZIB full cells deliver an ultra-stable cycling performance exceeding 19,000 cycles at 10 A g −1 . Furthermore, a practical high-loading pouch cell successfully achieves a high reversible capacity of 21.6 mAh after 200 cycles at 1 A g −1 . This work provides an effective strategy for designing multi-functional eutectic electrolytes toward practically viable, long-life AZIBs.