Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The [email protected] yolk-shell structure prepared by controlled reduction and selective removal of Sb₂O₃ from carbon coated Sb₂O₃ nanoparticles can accommodate the Sb swelling upon sodiation and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~ 554 mAh g⁻¹, good rate capability (315 mhA g⁻¹ at 10 C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na_0.9[Cu_0.22Fe_0.30Mn_0.48]O₂ cathodes and [email protected] carbon composite anodes demonstrate a high specific energy of ~ 130 Wh kg⁻¹ (based on the total mass of cathode and anode) in the voltage range of 2.0–4.0 V, ~ 1.5 times energy of full-cells with similar design using hard carbon anodes.

尽管钠离子电池的开发取得了巨大的进步，但寻找高能量和稳定的负极材料仍然是一个挑战。合金或转化型阳极材料是高比容量和低电势的有吸引力的候选材料，但是它们的应用由于大体积膨胀而受阻，因此电化学可逆性差且容量衰减快。在这里，我们以锑（Sb）为例来说明卵黄壳结构阳极用于高能Na-离子电池。通过从碳包覆的Sb ₂ O _3中选择性还原和选择性除去Sb ₂ O ₃制备的[受电子邮件保护的]卵黄壳结构纳米颗粒可以适应Sb在溶化过程中的溶胀，并提高抗粉化的结构/电完整性。它具有约554 mAh g ^-1的高比容量，良好的倍率能力（在10 C速率下为315 mhA g ^-1）和长循环能力（200个循环中92％的容量保持率）。O3-Na _0.9 [Cu _0.22 Fe _0.30 Mn _0.48 ] O ₂阴极和[受电子邮件保护的]碳复合阳极的全电池表现出〜130 Wh kg ^-1的高比能（基于阴极和阳极的总质量）在2.0–4.0 V的电压范围内，采用硬碳阳极的类似设计的全电池能量约为1.5倍。