N-methylpyrrolidinium-based ionic liquid, with fluorine function group, N-(2-fluoroethyl) N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide is proposed as the co-solvent for Si anode. Scanning electron microscope, X-ray photoelectron spectroscopy as well as the impedance measurement is conducted to investigate its effect on the solid electrolyte interface formation. Cycling tests show that it can much better improve the cycling stability of Si than fluoroethylene carbonate or F-free ionic liquid analogue.

中文翻译：

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锂离子电池中用于硅阳极的氟取代离子液体

提出了具有氟官能团的N-甲基吡咯烷鎓类离子液体，作为Si阳极的助溶剂，N-（2-氟乙基）N-甲基吡咯烷鎓双（三氟甲磺酰基）酰亚胺。进行了扫描电子显微镜，X射线光电子能谱和阻抗测量，以研究其对固体电解质界面形成的影响。循环测试表明，与碳酸氟代亚乙酯或不含F的离子液体类似物相比，它可以更好地改善Si的循环稳定性。