A triple-conductive catalytic and confining network for high-areal-capacity solid-state iron-air batteries

Conversion-type electrodes offer high energy density for solid-state batteries but suffer from sluggish ion transport, high phase-transition barriers, and structural degradation. Solid-state iron-air batteries, as a promising candidate for large-scale energy storage due to their economic and safety advantages, face these challenges. To overcome them, we design a catalytically active bi-continuous percolating network realized in an Fe 2 O 3 /La 0.65 Sr 0.35 MnO 3-δ /yttria-stabilized zirconia (YSZ) composite. This architecture establishes continuous ion/electron pathways, introduces catalytic interfaces that lower the Fe–O bond-breaking energy barrier, and provides a rigid scaffold to accommodate volume changes. The synergy of continuous conduction, interfacial catalysis, and mechanical confinement enables a remarkable areal capacity of 10.7 mAh cm −2 , a 14-fold improvement over conventional electrodes, along with exceptional cycling stability over 1,000 h. This work provides a general design blueprint for high-performance batteries based on earth-abundant conversion materials.