High-temperature sodium-sulfur batteries operating at 300-350 °C have been commercially applied for large-scale energy storage and conversion. However, the safety concerns greatly inhibit their widespread adoption. Herein, we report a room-temperature sodium-sulfur battery with high electrochemical performances and enhanced safety by employing a "cocktail optimized" electrolyte system, containing propylene carbonate and fluoroethylene carbonate as co-solvents, highly concentrated sodium salt, and indium triiodide as an additive. As verified by first-principle calculation and experimental characterization, the fluoroethylene carbonate solvent and high salt concentration not only dramatically reduce the solubility of sodium polysulfides, but also construct a robust solid-electrolyte interface on the sodium anode upon cycling. Indium triiodide as redox mediator simultaneously increases the kinetic transformation of sodium sulfide on the cathode and forms a passivating indium layer on the anode to prevent it from polysulfide corrosion. The as-developed sodium-sulfur batteries deliver high capacity and long cycling stability.

中文翻译：

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具有高容量和稳定循环性能的室温钠硫电池。

在300-350°C下工作的高温钠硫电池已在商业上用于大规模的能量存储和转换。但是，出于安全考虑，极大地阻碍了它们的广泛采用。本文中，我们报告了一种室温高钠硫电池，它采用“鸡尾酒优化”电解液体系，具有较高的电化学性能和增强的安全性，该电解液体系包含碳酸亚丙酯和碳酸氟代亚乙酯作为助溶剂，高浓度钠盐和三碘化铟作为助溶剂。添加剂。如通过第一性原理计算和实验表征所证实的，氟代碳酸亚乙酯溶剂和高盐浓度不仅显着降低了多硫化钠的溶解度，而且还在循环时在钠阳极上构建了坚固的固体电解质界面。三碘化铟作为氧化还原介体可同时提高阴极上硫化钠的动力学转化，并在阳极上形成钝化铟层，以防止其被多硫化物腐蚀。已开发的钠硫电池具有高容量和长循环稳定性。