Molecularly Aligned Insoluble Nanoaggregates for Ah‐Level Aqueous Zinc‐Ion Batteries

ABSTRACT Achieving stable Ah‐level aqueous zinc‐ion batteries (AZIBs) remains a critical challenge due to severe water decomposition and dendrite growth. Conventional aqueous electrolytes adopt soluble ligands to stabilize the interfaces, yet these species are insufficient to isolate interfacial water contact owing to their intrinsic hydrophilicity. Herein, we design a molecularly aligned electrolyte (MAE) that incorporates insoluble ligands in aqueous solutions to stabilize both electrodes. By utilizing the π−π stacking between benzylideneacetone (BA) and 2‐naphthol polyoxyethylene (NPE), insoluble BA molecules form nanoaggregates with NPE and are stably dispersed within the aqueous electrolyte. At both interfaces, the BA−NPE nanoaggregates form hydrophobic interfacial layers that prevent water attack, thereby effectively suppressing side reactions. In addition, BA−NPE nanoaggregates substantially increase the nucleation overpotential and form a fluorine‐rich solid electrolyte interphase (SEI), promoting dendrite‐free Zn plating/stripping. Consequently, the Zn//Zn cell exhibits stable cycling for over 4500 h at 1 mA cm −2 and 1 mAh cm −2 . More impressively, the Zn//NH 4 V 4 O 10 pouch cell delivers capacities exceeding 1.3 Ah for over 900 cycles with a retention rate of 81.8%, validating the significance of the insoluble ligand strategy under practical conditions.