Oyakhire Solomon T, Liao Sheng-Lun, Shuchi Sanzeeda Baig, Kim Mun Sek, Kim Sang Cheol, Yu Zhiao, Vilá Rafael A, Rudnicki Paul E, Cui Yi, Bent Stacey F
Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States.
Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Nano Lett. 2023 Aug 23;23(16):7524-7531. doi: 10.1021/acs.nanolett.3c02037. Epub 2023 Aug 11.
The composition of the solid electrolyte interphase (SEI) plays an important role in controlling Li-electrolyte reactions, but the underlying cause of SEI composition differences between electrolytes remains unclear. Many studies correlate SEI composition with the bulk solvation of Li ions in the electrolyte, but this correlation does not fully capture the interfacial phenomenon of SEI formation. Here, we provide a direct connection between SEI composition and Li-ion solvation by forming SEIs using polar substrates that modify interfacial solvation structures. We circumvent the deposition of Li metal by forming the SEI above Li/Li redox potential. Using theory, we show that an increase in the probability density of anions near a polar substrate increases anion incorporation within the SEI, providing a direct correlation between interfacial solvation and SEI composition. Finally, we use this concept to form stable anion-rich SEIs, resulting in high performance lithium metal batteries.
固体电解质界面（SEI）的组成在控制锂-电解质反应中起着重要作用，但电解质之间SEI组成差异的根本原因仍不清楚。许多研究将SEI组成与电解质中锂离子的整体溶剂化联系起来，但这种相关性并不能完全捕捉SEI形成的界面现象。在这里，我们通过使用修饰界面溶剂化结构的极性底物形成SEI，建立了SEI组成与锂离子溶剂化之间的直接联系。我们通过在锂/锂氧化还原电位以上形成SEI来避免锂金属的沉积。通过理论分析，我们表明极性底物附近阴离子概率密度的增加会增加SEI中阴离子的掺入，从而在界面溶剂化和SEI组成之间建立直接关联。最后，我们利用这一概念形成稳定的富含阴离子的SEI，从而实现高性能锂金属电池。
