Multiple‐Center Cation Ordering Mitigates Voltage Decay and Hysteresis in Sodium Layered Oxides

ABSTRACT P2‐type layered oxides, as promising cathode candidates for sodium‐ion batteries (SIBs), offer high working voltage and rapid Na ⁺ transport, yet suffer from progressive voltage decay and structural instability at deep states of charge, due to detrimental P2‐O2 phase transitions and irreversible oxygen redox. Herein, we introduce a multiple‐center honeycomb ordering strategy that incorporates LiMn ₆ , MgMn _6, and intrinsic NiMn ₆ topology within the transition‐metal layers of P2‐Na _0.67 Ni _0.33 Mn _0.67 O ₂ through rational Li/Mg co‐doping. We demonstrate that the LiMn ₆ order units disperse the NiMn ₆ superstructure domains to suppress long‐range phase evolution, while the MgMn ₆ motifs act as nanoscale anchors to immobilize Li ⁺ within the TM slabs and prevent its migration during oxygen redox. This synergistic topological design sustains a highly reversible solid‐solution reaction over a wide voltage range of 2.0–4.5 V, with minimal voltage hysteresis and a voltage decay of 0.002 V per cycle. The resulting P2‐Na _0.76 Li _0.10 Mg _0.08 Ni _0.15 Mn _0.67 O ₂ cathode delivers a high capcity of 134 mAh g ⁻¹ and retains an excellent capacity retention of 93.36% after 400 cycles, outperforming conventional analogues. These findings open a new avenue for tailoring the local structure of layered oxide cathodes to achieve voltage‐stable and high‐energy‐density SIBs.