Sodium-ion batteries (SIBs) with iron- and manganese-based cathode electrodes have exhibited great promise in the grid-scale energy storage systems, on the basis of the satisfactory theoretical capacity, as well as huge abundance, low price and non-toxicity of raw materials. However, the inferior cycle life of cathode materials originating from their poor structural stability remains a formidable challenge towards practical applications. Here, an efficient strategy of improving the structure durability is demonstrated in iron- and manganese-based cathodes by dual heteroatom doping. The as-obtained P2-type Na_0.65Li_0.08Cu_0.08Fe_0.24Mn_0.6O₂ cathode delivers superior cyclability (88.2% capacity retention for 500 cycles at 2C), fabulous rate capability (76% capacity retention at 5C compared to 0.1C), and a useable reversible capacity of around 85 mAh g⁻¹ at 0.1C. Through in-depth characterizations, the underlying structure-property relationship is established, revealing that the complete solid-solution reaction during cycling ensures the ultralow volume variation (as small as 0.7%) and excellent electrochemical performance. These results highlight the significance of fabricating a stable host for the design and development of advanced SIBs with long life.

具有铁和锰基阴极电极的钠离子电池（SIBs）在令人满意的理论容量以及丰度高、价格低和无毒的基础上，在电网规模的储能系统中表现出巨大的潜力的原材料。然而，正极材料由于其结构稳定性差而导致循环寿命较差仍然是实际应用的巨大挑战。在这里，通过双杂原子掺杂在铁基和锰基阴极中展示了一种提高结构耐久性的有效策略。得到的 P2 型 Na _0.65 Li _0.08 Cu _0.08 Fe _0.24 Mn _0.6 O ₂正极具有优异的循环性能（2C 下 500 次循环的容量保持率为 88.2%）、出色的倍率性能（5C 下的容量保持率为 76%，而 0.1C 下的容量保持率）以及 0.1C 下约 85 mAh g ^-1的可用可逆容量。通过深入的表征，建立了潜在的结构-性能关系，揭示了循环过程中完全的固溶反应确保了超低的体积变化（小至 0.7%）和优异的电化学性能。这些结果强调了制造稳定的主机对于设计和开发具有长寿命的先进 SIB 的重要性。