Zhang, S.-J.Hao, J.Li, H.Zhang, P.-F.Yin, Z.-W.Li, Y.-Y.Zhang, B.Lin, Z.Qiao, S.-Z.2022-05-162022-05-162022Advanced Materials, 2022; 34(23)0935-96481521-4095https://hdl.handle.net/2440/135126First published: 18 April 2022.Aqueous Zn–iodine (Zn–I2) batteries have been regarded as a promising energy-storage system owing to their high energy/power density, safety, and cost-effectiveness. However, the polyiodide shuttling results in serious active mass loss and Zn corrosion, which limits the cycling life of Zn–I2 batteries. Inspired by the chromogenic reaction between starch and iodine, a structure confinement strategy is proposed to suppress polyiodide shuttling in Zn–I2batteries by hiring starch, due to its unique double-helix structure. In situ Raman spectroscopy demonstrates an I5−-dominated I−/I2 conversion mechanism when using starch. The I5− presents a much stronger bonding with starch than I3−, inhibiting the polyiodide shuttling in Zn–I2 batteries, which is confirmed by in situ ultraviolet–visible spectra. Consequently, a highly reversible Zn–I2 battery with high Coulombic efficiency (≈100% at 0.2 A g−1) and ultralong cycling stability (>50 000 cycles) is realized. Simultaneously, the Zn corrosion triggered by polyiodide is effectively inhibited owing to the desirable shuttling-suppression by the starch, as evidenced by X-ray photoelectron spectroscopy analysis. This work provides a new understanding of the failure mechanism of Zn–I2 batteries and proposes a cheap but effective strategy to realize high-cyclability Zn–I2 batteries.en© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and re-production in any medium, provided the original work is properly cited.Zn corrosionZn-iodine batteriesshuttle effectstarchstructure confinementJournal article10.1002/adma.2022017162022-05-16608753Zhang, S.-J. [0000-0001-7738-0425]Hao, J. [0000-0002-5777-7844]Li, H. [0000-0003-0662-6939]Qiao, S.-Z. [0000-0002-1220-1761] [0000-0002-4568-8422]