All-in-One Graphene-Based Integrated Cathode for Li─O₂ Battery: Harmonizing High Energy, High Power, and Longevity

Li─O₂ batteries (LOBs) have attracted wide attention due to their high theoretical energy density, but their cathodes are throttled by two inextricable tradeoffs: capacity versus rate capability and capacity versus stability. These coupled constraints prevent simultaneous maximization of energy density, power density, and cycle life, stalling the transition of LOBs from laboratory concepts to practical power devices. Here, we break this deadlock with a free-standing, multiscale porous graphene electrode uniformly ornamented with Pt nanocatalysts. The meticulously regulated micron pores (pore diameter ≈ 3 µm) accommodate massive discharge deposits while maintaining rapid O₂/Li⁺/e^- transport, synergistically boosting areal capacity and rate capability. Concurrently, Pt catalyzes the LiOH pathway with low polarization and suppresses parasite reactions, extending cycle life even under large capacity cutoffs. As an oxygen cathode, this electrode delivers an areal capacity of 37.8 mAh/cm² at 0.2 mA/cm² and retains 40% capacity when the current quadruples to 0.8 mA/cm², translating to an energy density of 74.2 mWh/cm² (1330 Wh/kg_cell) at 1.0 mW/cm². The cell sustains operation for >800 h across cutoff capacities spanning 0.4-10 mAh/cm², marking a decisive step toward practical LOBs.