Molecular Weaving-Inspired Dual-Cross-Linked Natural-Polymer Hydrogel Electrolyte for Stable Aqueous Zn–I2 Battery

Aqueous zinc–iodine (Zn–I2) batteries are promising for sustainable energy storage owing to their intrinsic safety, environmental benignity, and the highly reversible redox chemistry of iodine. However, water-induced side reactions at the Zn anode and the shuttling effect of polyiodides trigger severe self-discharge and interfacial instability. Herein, a molecular-weaving–inspired strategy was developed, in which topological chain entanglements cooperate with dynamic ionic/coordination junctions to build a dual-cross-linked hydrogel electrolyte. In such weaving-inspired entangled networks, Zn2+-activated junction dynamics dissipate energy and prevent stress localization, while the enduring entanglement preserves network integrity. Simultaneously, the introduction of abundant coordination sites along the polymer backbone reconfigures the local Zn2+ solvation environment and mitigates Zn anode side reactions and dendrite growth. Moreover, these coordinated Zn2+ nodes effectively suppress the polyiodide shuttle without compromising ionic conductivity. Benefiting from these synergistic effects, the designed hydrogel electrolyte enables highly stable Zn plating/stripping, achieving an average Coulombic efficiency of 99.46% in Zn//Cu cells. The assembled Zn//I2 full cells deliver excellent durability with a high capacity retention of 87.8% after 9000 cycles at 5.0 A g–1. This work establishes a viable weaving-inspired design strategy for natural polymer-based hydrogel electrolytes toward durable aqueous Zn–I2 batteries and beyond.