Controlling Epitaxial Zn Growth via Guided Laser Patterning toward High‐Performance 6Ah Aqueous Zn||I 2 Batteries

ABSTRACT Aqueous zinc‐ion batteries (AZIBs) are attractive for grid‐scale energy storage because of their safety, low cost, and environmental benignity. However, their practical use is limited by interfacial instability at the Zn anode, which induces nonuniform Zn 2+ flux, dendritic growth, and parasitic H 2 evolution. Herein, we present a laser‐induced surface patterning stategy that guides Zn epitaxial growth through a resistance‐gradient‐driven mechanism. Laser ablation forms periodic concave micro‐holes, selectively removes the resistive carbonate‐based surface layer from the exposed regions, and reconstructs the Zn texture from the (101) plane to the (002) basal plane. This surface‐resistance contrast directs Zn 2+ flux into the patterned holes, which serve as uniform nucleation sites and three‐dimensional deposition reservoirs, enabling bottom‐up Zn filling and compact homogeneous surface growth. Consequently, the patterned Zn||Zn symmetric cells achieve an exceptional lifespan of 972 cycles under high‐rate conditions (10 mA cm −2 , 2 mAh cm −2 ). Furthermore, a 6.5 Ah Zn||I 2 pouch cell operating at 2C (10 × 18 cm 2 , areal capacity of 3.0 mAh cm −2 ) and employing the laser‐patterned Zn anode exhibits stable cycling for over 440 cycles, a Coulombic efficiency of 99.9%, and a capacity retention of 90.7%.