Anode/Cathode Dual‐Purpose Aluminum Current Collectors for Aqueous Zinc‐Ion Batteries

Abstract Rechargeable aqueous zinc (Zn)‐ion batteries (RAZIBs), which use non‐flammable aqueous electrolytes and low‐cost electrode materials, show great potential to boost the development of safe, cost‐effective, and highly efficient energy storage systems. The adoption of lightweight and inexpensive aluminum (Al) as current collectors seems to be a good vision, but Al exhibits an easily‐corroded nature and a high impedance in aqueous electrolytes, making it a challenge to realize the utilization of Al current collector in RAZIBs. In this study, through the direct current magnetron sputtering, niobium (Nb) coated Al (Al‐Nb) foils are prepared, which shows superior corrosion‐resistance in an aqueous solution, while maintaining a satisfying electronic conductivity. Moreover, the Al‐Nb foils can be adopted to both anode and cathode current collectors while exhibiting high coulombic efficiency and good cycling stability even when they are tested under a condition that can meet the real‐world application demands, e.g., the Zn||Al‐Nb half‐cell shows an average coulombic efficiency of 99.17% in 320 cycles under a current density of 25 mA cm −2 and a galvanizing capacity of 6.25 mAh cm −2 . The superior performance of the modified Al current collectors may mark a significant step toward the development of high‐energy‐density aqueous batteries.