<p>Aluminum-ion-based capacitors have emerged as attractive energy storage systems owing to their intrinsic safety, natural abundance, and high theoretical capacity. Herein, a high-performance hydrated vanadium oxide (V₂O₅. 1.6H₂O) is demonstrated as an electrode material for reversible Al³⁺ ion storage in an aqueous electrolyte. It is found that hydrated vanadium oxide exhibits enhanced electrochemical performance in 1&#xa0;M AlCl₃ aqueous electrolyte, delivering a discharge specific capacitance of 210&#xa0;F g^− 1 over 100 cycles at a current density of 1&#xa0;A g^− 1. To further improve the stability, a poly(ethylene oxide) (PEO)-based gel electrolyte was incorporated into the 1&#xa0;M AlCl₃ electrolyte, resulting in superior electrochemical performance. In addition, ex-situ characterization techniques further confirm the Al³⁺ ion storage process. Finally, a symmetric Al³⁺ ion capacitor is assembled, which exhibits a high power density of 4750&#xa0;W kg^− 1 at a current density of 5&#xa0;A g^− 1, with excellent rate capability and enhanced cycling stability. This work highlights the motivation for developing next-generation safe and high-performance Al³⁺ based capacitors.</p>