Patent ID: 8310809

Claim:
An electric double-layer capacitor comprising: a cylindrical case having a bottom and a side surface, the case having an opening; a capacitor element accommodated in the case, the capacitor element including a first collector made of metal foil wound around a center axis, a first polarizable electrode layer wound around the center axis and provided on the first collector in a direction toward the center axis, a first separator wound around the center axis and provided on the first polarizable electrode layer in the direction toward the center axis, a second collector made of metal foil wound around the center axis and provided on the first separator in the direction toward the center axis, a second polarizable electrode layer wound around the center axis and provided on the second collector in the direction toward the center axis, a second separator wound around the center axis and provided on the second polarizable electrode layer in the direction toward the center axis, a first electrode extending from the first collector and parallel to the center axis, and a second electrode extending from the second collector in a direction opposite to the first electrode and parallel to the center axis; a driving electrolyte accommodated in the case; and a terminal plate provided at the opening of the case and joined to the first electrode of the capacitor element, wherein the capacitor element has a first end surface and a second end surface opposite to each other in a direction of the center axis, the second end surface facing the bottom of the case, the first electrode extends from the first end surface and has a spiral shape extending continuously around the center axis, the second electrode extends from the second end surface and is joined to the bottom of the case, and the second electrode has a spiral shape extending continuously around the center axis, the first electrode and the second electrode are tilted away from the center axis of the capacitor element, and one of the first electrode and the second electrode is entirely tilted away from the center axis of the capacitor element.