Molecular Polarity Attenuation Tailors Weak Solvation Structure with Accelerated Kinetics and Robust SEI for High‐Areal‐Capacity Large‐Format Pouch Zn‐Based Batteries

ABSTRACT Large‐format, high‐areal‐capacity aqueous Zn‐ion batteries are pivotal for practical energy storage but remain hindered by sluggish kinetics, heterogeneous local reactions, and drastic interfacial deformation. In this work, a molecular polarity‐weakening strategy of electrolyte additive is proposed to customize a rapid‐reaction‐kinetics solvation structure and a hybrid solid‐electrolyte interphase (SEI) for Zn metal pouch batteries. Leveraging this synergistic solvation‐SEI regulation, a 25 cm 2 Zn||Zn pouch symmetric cell achieves unprecedent 352 h stable cycling at 40 mAh cm −2 (DOD = 68%, 10 mA cm −2 ). More importantly, a 100 cm 2 Zn||I 2 pouch full battery delivers a high areal capacity of 9.8 mAh cm −2 and sustains nearly 400 h of stable cycling.