<p>The escalating demand for safe, high-energy-density storage drives the pursuit of rechargeable aluminum batteries (RABs) utilizing a nonflammable ionic liquid electrolyte. While WO₃ offers rich redox chemistry and high theoretical capacity, its practical application in RABs is hindered by structural degradation. Herein, a reduced graphene oxide-supported monocrystalline WO₃ nanoplate (rGO-WO₃) cathode is reported to address these challenges. Combined electrochemical analysis, spectroscopic characterization, and density functional theory simulations reveal that the rGO substrate simultaneously enhances electrode conductivity and strongly adsorbs dissolved W species, thereby significantly mitigating structural collapse. As a result, the rGO-WO₃ composite achieves a high reversible capacity of 166.2 mAh·g⁻¹ at 0.1 A·g⁻¹, with exceptional cycling stability (81.3% retention after 1000 cycles) and a near-unity Coulombic efficiency of ~ 100%. Mechanistic studies confirm the intercalation/deintercalation of cationic Al-species (specifically, AlCl₂⁺/AlCl²⁺), coupled with reversible W⁶⁺/W⁵⁺ and W⁵⁺/W⁴⁺ redox reactions at the cathode, alongside electrochemical Al stripping/plating at the anode. This work elucidates critical interfacial interactions and reaction pathways, establishing a design paradigm for high-performance RAB cathodes.</p> Graphical abstract <p></p>