Trinity Cooperative Electrode as a High‐Performance Electrocatalytic Host for Ultra‐Stable, High‐Rate Zinc–Halogen Batteries

Abstract

ABSTRACT Aqueous zinc–halogen batteries (ZHBs) offer safety and low cost but are hindered by halogen dissolution, shuttle effects, and sluggish interfacial kinetics. We present a trinity cooperative electrode (TCE) that integrates a conductive polymer, a supramolecular solvent matrix, and an elastic polymer network to simultaneously enhance electronic conductivity, mechanical/solvent stability, and halogen immobilization. The iodine conversion pathway is elucidated by in situ/ex situ characterizations and molecular dynamics simulations. In ZnI 2 + Zn(CF 3 SO 3 ) 2 electrolytes, TCE‐based cells deliver 255 mAh g −1 at 1 A g −1 , retain 150 mAh g −1 at 50 A g −1 for > 50 000 cycles, and operate reliably at −10°C. The TCE also catalyzes Br − /Br 2 conversion in Zn(CF 3 SO 3 ) 2 + ZnBr 2 and enables sequential multielectron reactions in a ternary Zn(CF 3 SO 3 ) 2 + ZnI 2 + ZnBr 2 electrolyte, achieving ∼200 mAh g −1 at 30 A g −1 for > 22 000 cycles. This approach advances high‐energy, long‐life ZHBs through pseudocapacitive interfacial chemistry.