Breaking Barriers Toward Practicality: Critical Materials and Strategies for High‐Energy‐Density Aqueous Zinc‐Ion Batteries

ABSTRACT Driven by the demands of grid‐scale energy storage and the electrification of transport, achieving superior energy density is pivotal to establishing a more sustainable and economically resilient battery ecosystem. However, aqueous zinc‐ion batteries (ZIBs), despite their cost‐effectiveness, inherent safety, high theoretical capacity (820 mAh g −1 ), and favorable redox potential (−0.762 V vs. SHE), still suffer from insufficient energy densities that fall short of commercial requirements. In this review, the obstacles hindering energy density and fundamental pathways toward high‐energy‐density ZIBs are systematically elucidated. Subsequently, recent advancements in optimization strategies are critically analyzed, encompassing electrode engineering, electrolyte optimization, and separator modification. Finally, a forward‐looking perspective is provided on the design principles and potential research directions for developing high‐energy‐density ZIBs.