Rechargeable potassium-ion batteries with honeycomb-layered tellurates as high voltage cathodes and fast potassium-ion conductors.
Rechargeable potassium-ion batteries with honeycomb-layered tellurates as high voltage cathodes and fast potassium-ion conductors.
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DOI：
10.1038/s41467-018-06343-6
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发表时间：
2018-09-20
影响因子：
16.6
通讯作者：
Shikano M
中科院分区：
文献类型：
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作者：
Masese T;Yoshii K;Yamaguchi Y;Okumura T;Huang ZD;Kato M;Kubota K;Furutani J;Orikasa Y;Senoh H;Sakaebe H;Shikano M
可充电钾离子电池不仅作为锂离子技术的有前途的低成本替代品，而且作为高压能量存储系统，已经获得了越来越多的关注。然而，它们的发展和可持续性受到缺乏能够允许大钾离子可逆插入的合适电极材料的困扰。在这里，对钾基材料数据库的探索使我们发现了钾离子传导层状蜂窝结构。它们显示出在高电压（对于K2 Ni 2 TeO 6为~ 4V）下在基于双（三氟磺酰基）酰亚胺钾的稳定离子液体中可逆插入钾离子的能力，并且表现出显著的离子电导率，例如对于K2 Mg 2 TeO 6在298 K下为~0.01 mS cm-1，在573 K下为~40 mS cm-1。除了可用作固体电解质的快速钾离子导体外，这些层状蜂窝状框架在层状阴极中提供最高的电压，成为高能量密度钾离子电池发展的主要候选者。钾离子电池的发展要求正极材料在循环过程中能够保持结构稳定性。在这里，作者开发了蜂窝层状碲酸盐K2 M2 TeO 6，提供高离子电导率和可逆嵌入大K离子在高电压下。
Rechargeable potassium-ion batteries have been gaining traction as not only promising low-cost alternatives to lithium-ion technology, but also as high-voltage energy storage systems. However, their development and sustainability are plagued by the lack of suitable electrode materials capable of allowing the reversible insertion of the large potassium ions. Here, exploration of the database for potassium-based materials has led us to discover potassium ion conducting layered honeycomb frameworks. They show the capability of reversible insertion of potassium ions at high voltages (~4 V for K2Ni2TeO6) in stable ionic liquids based on potassium bis(trifluorosulfonyl) imide, and exhibit remarkable ionic conductivities e.g. ~0.01 mS cm−1 at 298 K and ~40 mS cm–1 at 573 K for K2Mg2TeO6. In addition to enlisting fast potassium ion conductors that can be utilised as solid electrolytes, these layered honeycomb frameworks deliver the highest voltages amongst layered cathodes, becoming prime candidates for the advancement of high-energy density potassium-ion batteries. The development of potassium-ion batteries requires cathode materials that can maintain the structural stability during cycling. Here the authors have developed honeycomb-layered tellurates K2M2TeO6 that afford high ionic conductivity and reversible intercalation of large K ions at high voltages.