There are provided a novel onium salt and a method for optimizing the interface of a negative electrode by the use of the novel onium salt and /or a conventional onium salt. Such a method is characterized in that an electrolyte comprising novel 2, 2, 2-trifluoro-N-(trifluoromethanesulfonyl) acetamide · tetraethyl ammonium salt is made to intervene between a negative electrode and a positive electrode in an electrochemical device having the constitution: a negative electrode | an electrolyte | a positive electrode, thereby constructing an electrode structure in the electrochemical device, and applying a voltage between the negative electrode and the positive electrode so as for the negative electrode to have a potential of -1 V to -5 V in terms of the potential relative to a reference electrode of I-/I3-, thereby forming a passive-state layer comprising a decomposition product of the above electrolyte or salt on the surface of the above negative electrode.
提供了一种新型鎓盐和一种通过使用该新型鎓盐和/或传统鎓盐优化负电极界面的方法。这种方法的特征在于,在具有以下结构的电
化学装置中,由新型 2,2,2-三
氟-N-(三
氟甲磺酰基)乙酰胺-
四乙基铵盐组成的电解质被用于负极和正极之间:负极 | 电解质 | 正极,从而在电
化学装置中构建电极结构,并在负极和正极之间施加电压,使负极相对于 I-/I3- 参比电极的电位为 -1 V 至 -5 V,从而在上述负极表面形成由上述电解质或盐的分解产物组成的被动态层。