Sodium-ion batteries have been explored extensively due to its abundant reserve and low cost. However, reports on full symmetric battery with the same electrode materials are relatively less than asymmetrical battery. In this work, symmetric sodium-ion battery based on layered P2-Na_0.67[Zn_xMn_1-x]O₂ (x = 0.1, 0.2, 0.28, 0.34) as both positive and negative electrode materials are studied comprehensively. This active material shows two electrochemical working windows with reversible lattice oxygen redox and Mn⁴⁺/Mn³⁺ redox couple. The positive side Na_0.67[Zn_0.28Mn_0.72]O₂ provides a highly reversible capacity of 170 mAh g⁻¹ at 0.05C (10 mA g⁻¹⁾ between 2.0–4.2 V and outstanding capacity retention of 77.2% after 100 cycles. Na_0.67[Zn_0.28Mn_0.72]O₂ electrode also exhibits excellent rate performance up to a high rate of 5C which is the best among the pure anionic-redox based cathodes. In addition, an average voltage of about 2.0 V versus Na⁺/Na is obtained as negative electrode material, with a reversible capacity of 99 mAh g⁻¹. This full symmetric battery also exhibits excellent rate performance and cycle stability which are related to Zn doping. As a cost-effective element, zinc has been used as inactive atom to induce the anionic redox and enhance the crystal structure. This is the first time to explore symmetric sodium-ion battery with anionic redox.

钠离子电池因其储量丰富、成本低廉而被广泛探索。然而，关于具有相同电极材料的全对称电池的报道相对少于非对称电池。在这项工作中，基于层状P 2-Na _0.67 [Zn _x Mn _{1- x} ]O ₂ (x = 0.1, 0.2, 0.28, 0.34) 作为正负极材料的对称钠离子电池进行了全面的研究。这种活性材料显示出两个电化学工作窗口，具有可逆的晶格氧氧化还原和 Mn ⁴⁺ /Mn ³⁺氧化还原对。正极 Na _0.67 [Zn _0.28 Mn _0.72 ]O₂在 0.05C (10 mA g ^-1)和 2.0-4.2 V 之间提供 170 mAh g ^-1的高度可逆容量和 100 次循环后 77.2% 的出色容量保持率。Na _0.67 [Zn _0.28 Mn _0.72 ]O ₂电极在高达5C的高倍率下也表现出优异的倍率性能，这是纯阴离子-氧化还原基阴极中最好的。此外，作为负极材料获得约2.0 V vs Na ⁺ /Na的平均电压，可逆容量为99 mAh g ^-1. 这种完全对称的电池还表现出与锌掺杂相关的优异倍率性能和循环稳定性。作为一种具有成本效益的元素，锌已被用作惰性原子以诱导阴离子氧化还原并增强晶体结构。这是首次探索具有阴离子氧化还原作用的对称钠离子电池。