Aqueous electrolytes have the potential to overcome some of the safety issues associated with current Li-ion batteries intended for large-scale applications such as stationary use. We recently discovered a lithium-salt dihydrate melt, viz., Li(TFSI)_0.7(BETI)_0.3·2H₂O, which can provide a wide potential window of over 3 V; however, its reductive stability strongly depends on the electrode material. To understand the underlying mechanism, the interfacial structures on several electrodes (C, Al, and Pt) were investigated by conducting molecular dynamics simulation under the constraint of the electrode potential. The results showed that the high adsorption force on the surface of the metal electrodes is responsible for the increased water density, thus degrading the reductive stability of the electrolyte. Notably, the anion orientation on Pt at a low potential is unfavorable for the formation of a stable anion-derived solid electrolyte interphase, thus promoting hydrogen evolution. Hence, the interfacial structures that depend on the material and potential of the electrode mainly determine the reductive stability of hydrate-melt electrolytes.

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水合熔体上电极相关界面结构的理论分析

水性电解质有可能克服与目前用于大规模应用（例如固定使用）的锂离子电池相关的一些安全问题。我们最近发现了一种锂盐二水合物熔体，即Li（TFSI）_0.7（BETI）_0.3 ·2H ₂O，可以提供超过3 V的宽电位窗口；然而，其还原稳定性强烈取决于电极材料。为了理解其基本机理，在电极电势的约束下，通过进行分子动力学模拟研究了几个电极（C，Al和Pt）上的界面结构。结果表明，金属电极表面的高吸附力是水密度增加的原因，从而降低了电解质的还原稳定性。值得注意的是，低电位的Pt上的阴离子取向不利于形成稳定的阴离子衍生的固体电解质中间相，从而促进氢的释放。因此，