ELECTRIC DOUBLE-LAYER CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide an electric double-layer capacitor which is suppressed in self-discharging. SOLUTION: In this electric double-layer capacitor having an electrolytic solution between electrodes, the electrolytic solution contains a polymeric compound (A), and when a voltage is impressed upon the solution by using the electrodes, the diffusion resistance R2 of electrolytic ions in the solution measured by a measuring method, in which Cole-Cole plotting is made, by measuring the impedance when an AC frequency is changed from 1 mHz to 20 kHz, under the condition of 2.5 V bias voltage and 5 mV AC voltage at 25 deg.C by the AC impedance method is larger than a diffusion resistance R1 of the electrolytic ions in the electrolytic solution, when the polymeric compound (A) is removed from the solution which is measured by the same measuring method.