Abstract The composite solid electrolytes (CSEs) inherits the high safety of the inorganic solid electrolyte and the easy processing of the organic polymer electrolyte, thereby exhibiting a broad application prospect. However, the performance of the CSE was hard to realizing its practical application in lithium metal batteries. Herein, the significant impact of CSE performance brought about by the addition of ionic liquids was studied and summarized: significantly increase ionic conductivity; constructing a viscoelastic interface between electrode and electrolyte to reduce the interface impedance; forming a stable and LiF-rich SEI at the negative electrode to inhibit the growth of lithium dendrites; wetting the LiFePO4 porous cathode. The LiFePO4/CSE-60/Li battery displays high initial discharge specific capacity of 158.2 mAh g−1 and a capacity retention of 86.3% after 400 cycles at 1 C at 55 °C, and with coulombic efficiency of 99.7%. The surface of the lithium metal anode after long-term cycling exhibits to dendrite-free morphology. This research highlights the critical role that ionic liquids play in improving the performance of CSEs and will shed light on designing CSEs for LMB practical applications.

中文翻译：

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用于高温/长寿命/无枝晶锂金属电池的离子液体增强复合固体电解质

摘要 复合固体电解质（CSEs）继承了无机固体电解质的高安全性和有机聚合物电解质的易加工性，具有广阔的应用前景。然而，CSE的性能很难实现其在锂金属电池中的实际应用。在此，研究并总结了离子液体的加入对CSE性能的显着影响：显着提高离子电导率；在电极和电解质之间构建粘弹性界面以降低界面阻抗；在负极形成稳定且富含 LiF 的 SEI，以抑制锂枝晶的生长；润湿 LiFePO4 多孔阴极。LiFePO4/CSE-60/Li 电池显示出 158 的高初始放电比容量。2 mAh g-1，55 °C、1 C、400次循环后容量保持率为86.3%，库仑效率为99.7%。长期循环后的锂金属负极表面呈现无枝晶形态。这项研究强调了离子液体在提高 CSE 性能方面的关键作用，并将为 LMB 实际应用的 CSE 设计提供启示。