Polyzwitterionic hydrogel electrolytes based on imidazolium cations and sulfonate anions enable stable Zn–I 2 batteries by regulating Zn deposition and inhibiting polyiodide shuttle

), and the flexible pouch cell maintains stable operation under extreme conditions. These cation-anion synergistic polyzwitterionic hydrogel electrolytes provide a novel strategy for addressing dendrite growth and polyiodide shuttle issues in zinc-iodine batteries.