| abstract |
A novel onium salt is provided and the cathode interface is titrated with the novel onium salt and / or conventional onium salt as an electrolyte. An electrolytic solution containing the novel 2,2,2-trifluoro-N- (trifluoromethanesulfonyl) acetamide tetraethylammonium salt is placed between the cathode and the anode in an electrochemical device consisting of a cathode | electrode | electrolyte | anode. by interposing a voltage is applied between the electrodes constituting the structure body of the electrochemical device, the negative electrode and a positive electrode potential of the negative electrode I - represented by the potential of when the / I 3- to reference electrode as -1V~-5V Thus, a passivation layer made of a decomposition product of the electrolyte solution or salt is formed on the surface of the cathode. |