Full‐Scale Regulation Enabled High‐Performance Sodium O3‐Type Layered Cathodes

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O3‐type cathodes hold considerable promise in achieving rapid commercialization due to high energy density. However, severe structural/interfacial deterioration, along with kinetic hindrance, typically resulting in rapid capacity fading and serious safety risk at elevated cut‐off voltages. Herein, inspired from solubility limitation of hetero‐elements, synchronous surface‐to‐bulk multifunctionally full‐scale modified O3‐NaNi 1/3 Fe 1/3 Mn 1/3 O 2 is proposed to maintain its state of health (SOH). The perovskite‐type CaZrO 3 protective layer in situ formed on the surface of primary particles, helps to construct a stable cathode‐electrolyte‐interphase architecture, mitigate the unexpected interfacial side reactions and prevent transition metal dissolution. Simultaneously, Ca 2+ pillars, robust Zr−O bonds and the highly electronegative F − are adequately anchored into ternary lattice sites of Na‐TM−O, respectively, thereby reinforcing the TMO 6 octahedra and facilitating Na + diffusion. Notably, the intrinsic lattice strain is effectively alleviated due to an additional intergrowth phase transition of P3‐OP2. More impressively, migration of Jahn‐Teller distorted Fe 4+ O 6 is further restrained, originating from the strengthened coordination environment under deep‐desodiation state. Consequently, as‐designed NFM‐CZF achieves an impressive rate capability and a remarkable capacity retention of 83.8 % after 300 cycles at 2 C. This elaborate work shed valuable insight into mechanism of regulating internal full Wyckoff‐site and external surface structure for sodium‐ion batteries with enhanced durability.