Bridging Electrolyte Bulk and Interfacial Chemistry: Dynamic Protective Strategy Enable Ultra‐Long Lifespan Aqueous Zinc Batteries

The main bottleneck of rechargeable aqueous zinc batteries (AZBs) is their limited cycle lifespans stemming from the unhealthy electrolyte bulk and fragile interface, especially in the absence of dynamic protection mechanism between them. To overcome this limitation, benefitting from their synergistic physical and chemical properties, chitin nanocrystals (ChNCs) are employed as superior colloid electrolyte to bridge electrolyte bulk and interfacial chemistry for ultra-long lifespan AZBs. This unique strategy not only enables continuous optimization of the electrolyte bulk and interfacial chemistry within the battery but also facilitates self-repairing of mechanical damage both internally and externally, thereby achieving comprehensive, persistent, and dynamic protection. As a result, the modified zinc (Zn) cells present high Zn plating/stripping coulombic efficiencies of 97.71 % ~99.81 % from 5 to 100 mA cm^-2, and remarkably service lifespan up to 8,200 h (more than 11 months). Additionally, the Zn//MnO₂ full cell exhibits a high capacity retention of 70.1 % after 3,000 cycles at 5 A g^-1. This dynamic protective strategy to challenge aqueous Zn chemistry may open up a new avenue for building better AZBs and beyond.