OUTER SHEATH FOR ELECTROCHEMICAL DEVICE AND ELECTRIC DOUBLE LAYER CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide an outer sheath for electrochemical device capable of enhancing the long-term reliability of the electrochemical device and the energy density per unit volume of the electrochemical device.SOLUTION: An outer sheath for an electrochemical device includes: an outer sheath body having a housing part having an opening; and a lid body closing the opening of the housing part. The housing part includes: a bottom surface which is located on the side opposite to the opening; and a side surface extending toward the lid body from the bottom surface. A recess recessed toward the inner side of the housing part is formed on the side surface.