Solid Solution Alloys Current Collectors for Stable Aqueous Zinc‐Based Battery Anodes

ABSTRACT While Zn foils are commonly employed as anodes in aqueous zinc batteries (AZBs), practical devices still require an additional inert current collector. Copper, despite its success in lithium‐ion batteries, often aggravates Zn dendrite growth, corrosion, and hydrogen evolution in AZBs. Here, we design three solid‐solution alloys—Cu‐0.3Ag, Cu‐0.3In, and Cu‐0.3Sn—via vacuum melting followed by rolling, a process readily scalable for industrial production. Comprehensive characterization of lattice structure, binding energies, zinc deposition morphology, and intermetallic formation identifies Cu‐0.3Sn as the most effective collector for enhancing Zn anode reversibility. Its superior zincophilicity promotes the vertical growth of Zn crystal planes ((101), (110), (100)), thereby suppressing dendrite formation and parasitic reactions. Cu‐0.3Sn further outperforms stainless steel and carbon cloth in mitigating hydrogen evolution and corrosion. Electrochemical testing demonstrates a Zn reversibility of 99.88% over 4000 cycles at 5 mA cm −2 . Full cells pairing Zn@Cu‐0.3Sn with HATN‐3CN cathodes exhibit exceptional durability over 21,000 cycles and maintain a coulombic efficiency of 99.84% for 115 cycles at −20°C. Moreover, a high‐loading Zn@Cu‐0.3Sn||MnO 2 pouch cell delivers >200 mAh g −1 at 5 A g −1 . Collectively, these findings establish Cu‐0.3Sn as a scalable, cost‐effective current collector that enables durable, dendrite‐free Zn anodes for practical AZBs.