Lattice Distortion Confinement Induced by Cationic Vacancy for Ambient Temperature Durable Aluminum‐Ion Batteries

Abstract 3D accessible Mn‐based Prussian blue analogues (PBAs) framework shows great potential in serving as host for carriers. However, their inevitable Jahn–Teller distortion (JTD) induced by Mn 3+ ions bring uncertainty for structural and phase‐change robustness during carrier reversible intercalation, particularly for highly charged Al 3+ ions with strong Coulombic interaction. Herein, a cationic vacancy design on Mn sites (V Mn ) is proposed for high‐performance Al 3+ reversible storage. By virtue of low‐cost Na 2 EDTA molecules, the introduction of V Mn , the undesired JTD, and corresponding phase‐change can be well‐suppressed. As a result, the enhanced structural robustness of PBAs framework exhibits excellent long‐term cyclic stability and favorable intercalation energies for reversible Al 3+ ions storage. In addition, as‐assembled MoO 3 //V Mn ‐PBAs full cell batteries can operate in a wide temperature range from −15 to 50 °C, without any additives in aqueous electrolyte. This work highlights the comprehensive availability of cationic vacancy strategy and aqueous Al‐ion batteries within a wide range of ambinent temperature, further, providing novel sight for sustainable development for next‐generation energy storage technique.