Intrinsically safe sodium‐ion batteries (SIBs) are considered a promising candidate for large‐scale energy storage systems. However, the high flammability of conventional electrolytes may pose serious safety threats and even explosions. Herein, we propose a strategy of constructing a deep eutectic electrolyte (DEE) to boost the safety and electrochemical performance of succinonitrile (SN)‐based electrolyte. The strong hydrogen bond between S = O of 1,3,2‐dioxathiolane‐2,2‐dioxide (DTD) and the α‐H of SN endows the enhanced safety and compatibility of SN with Lewis bases. Meanwhile, the DTD participates in the inner Na+ sheath and weakens the coordination number of SN. The unique solvation configuration promotes the formation of robust gradient inorganic‐rich electrode‐electrolyte interphase, and merits stable cycling of half cells in a wide temperature range, with a capacity retention of 82.8% after 800 cycles (25 °C) and 86.3% after 100 cycles (60 °C). Correspondingly, the full cells deliver tremendous improvement in cycling stability and rate performance.This article is protected by copyright. All rights reserved

中文翻译：

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用于本质安全高压钠离子电池的不可燃丁二腈基深共晶电解质

本质安全钠离子电池（SIB）被认为是大规模储能系统的有希望的候选者。然而，传统电解液的高易燃性可能会带来严重的安全威胁，甚至爆炸。在此，我们提出了构建深共晶电解质（DEE）的策略，以提高丁二腈（SN）基电解质的安全性和电化学性能。 1,3,2-二氧硫杂环己烷-2,2-二氧化物（DTD）的S = O与SN的α-H之间的强氢键赋予SN增强的安全性以及与路易斯碱的相容性。同时，DTD参与内部Na+鞘并削弱了SN的配位数。独特的溶剂化构型促进了强梯度富无机电极-电解质界面的形成，并有利于半电池在较宽的温度范围内稳定循环，800次循环（25°C）后容量保持率为82.8%，循环后容量保持率为86.3%。 100 个循环（60°C）。相应地，全电池在循环稳定性和倍率性能方面提供了巨大的改进。本文受版权保护。版权所有