| abstract |
An electrochemical device of the present invention includes: a main body formed by rolling up an anode foil, a cathode foil and a separator disposed therebetween, each of the anode foil and the cathode foil having a lead wire connected thereto, wherein the main body is impregnated with an electrolytic solution; a tubular case having a bottom surface for accommodating the main body; and a seal for sealing an opening of the tubular case, which includes a through hole for the lead wire to pass therethrough. The electrolytic solution contains about 5 to about 100 parts by weight of a quaternary salt of a compound having an alkyl-substituted amidine group as an electrolyte with respect to 100 parts by weight of an organic solvent containing at least one of gamma-butyrolactone and propylene carbonate. The seal is an elastic body containing a butyl rubber polymer which is a copolymer of isobutylene, isoprene and divinylbenzene, and a peroxide as a vulcanizing agent. At least a portion of the seal has a hardness of about 65 International Rubber Hardness Degrees. |