Electric double layer capacitor

摘要

The invention is intended to reduce expansion proportion of electric double layer capacitors by combining nonporous carbonaceous electrodes produced by a specific method with an electrolyte of a specific structure. Provided is an electric double layer capacitor comprising nonporous carbonaceous electrodes soaked in an organic electrolytic solution, wherein the organic electrolytic solution contains a pyrrolidinium compound salt as a solute, and wherein the carbonaceous electrodes are electrodes obtained by the method comprising a step of obtaining a carbon powder by prebaking a needle coke green powder under an inert atmosphere, baking the prebaked needle coke powder in the presence of alkali hydroxide under an inert atmosphere, and removing the alkali hydroxide; and a step of shaping the carbon powder.