A production method efficiently produces a box sealed type solid electrolytic capacitor in which a capacitor element is accommodated in a box-shaped case. The method includes a step of preparing a bottom wall substrate having bottom walls. A step forms cathode anode circuit patterns on the bottom wall substrate. A step prepares a peripheral side wall substrate having peripheral side walls. A step prepares a peripheral side wall substrate in which a plurality of through-holes are provided that correspond to plurality of bottom wall structural portions. A step fixes a capacitor element to each bottom wall structural portion of the bottom wall substrate. A step obtains a capacitor continuous member in which a plurality of capacitor structural portions structuring a solid electrolytic capacitor by attaching an upper lid substrate on the peripheral side wall substrate. A step obtains a plurality of solid electrolytic capacitors by cutting the capacitor continuous member.

A solid electrolytic capacitor includes a capacitor element, an anode terminal, a cathode terminal, and a sealing resin covering the capacitor element. The anode terminal includes a support portion for supporting the capacitor element, and an anode standing portion formed upright relative to the support portion. The capacitor element includes an anode wire projecting from a porous sintered body. The anode wire is placed on the upper end face of the anode standing portion. The anode wire and the anode standing portion have parts that are exposed from the sealing resin and covered by an electrically conductive anode terminal covering layer for ensuring electrical connection between the anode wire and the anode terminal.

A solid electrolytic capacitor includes a capacitor element, an anode terminal, a cathode terminal, and a sealing resin covering the capacitor element. The anode terminal includes a support portion for supporting the capacitor element, and an anode standing portion formed upright relative to the support portion. The capacitor element includes an anode wire projecting from a porous sintered body. The anode wire is placed on the upper end face of the anode standing portion. The anode wire and the anode standing portion have parts that are exposed from the sealing resin and covered by an electrically conductive anode terminal covering layer for ensuring electrical connection between the anode wire and the anode terminal.

To reduce the occurrence of capacitor mounting failure on a circuit board in the solder reflow process, the capacitor element is housed in the bottomed cylindrical outer case and sealed with a sealing member the open end of the outer case, the lead terminal derived from the capacitor element is formed through the sealing member a capacitor body, a base having a bottom surface portion and a side wall formed so as to surround the outer periphery of the capacitor body with a through hole through which the lead terminal penetrates, a capacitor having a convex portion protruding toward the capacitor body from the inner surface of the side wall, the caulking portion formed by caulking the side surface of the outer case the convex portion is disposed, providing a gap portion between the caulking portion and the convex portion.

To reduce the occurrence of capacitor mounting failure on a circuit board in the solder reflow process, the capacitor element is housed in the bottomed cylindrical outer case and sealed with a sealing member the open end of the outer case, the lead terminal derived from the capacitor element is formed through the sealing member a capacitor body, a base having a bottom surface portion and a side wall formed so as to surround the outer periphery of the capacitor body with a through hole through which the lead terminal penetrates, a capacitor having a convex portion protruding toward the capacitor body from the inner surface of the side wall, the caulking portion formed by caulking the side surface of the outer case the convex portion is disposed, providing a gap portion between the caulking portion and the convex portion.

An electrolytic capacitor that includes a capacitor element including an anode portion made of a metal layer, a dielectric layer on an outer surface of the metal layer, and a cathode portion on an outer surface of the dielectric layer; an insulating resin body covering the capacitor element; and a gas barrier film on an outer surface of the insulating resin body, the gas barrier film having a water vapor transmittance of 1 g/m.sup.2 per day or less.

An electrolytic capacitor that includes a capacitor element including an anode portion made of a metal layer, a dielectric layer on an outer surface of the metal layer, and a cathode portion on an outer surface of the dielectric layer; an insulating resin body covering the capacitor element; and a gas barrier film on an outer surface of the insulating resin body, the gas barrier film having a water vapor transmittance of 1 g/m.sup.2 per day or less.

The present disclosure relates to an energy storage device improved in reliability and durability. The energy storage device includes: an electrode element including an anode plate, a separator, and a cathode plate; a housing configured to accommodate the electrode element; a terminal plate configured to cover an opened top surface of the housing; and electrode terminals protruding to an outside of the terminal plate and including an anode terminal, a cathode terminal, and two terminal pins. The terminal plate includes a metal member and a sealing member that surrounds a top surface and a bottom surface of the metal member, and an outermost side surface between the top surface and the bottom surface, and the sealing member includes an outer upper horizontal portion, an outer lower horizontal portion, and an outer vertical portion disposed between the housing and the metal member.

A capacitor element that has an anode body, a dielectric oxide film layer covering the anode body, and a cathode body formed on the dielectric oxide film layer; an exterior body that covers the capacitor element; a contact layer that is on an anode terminal, which is an end portion of the anode body, and has a surface with a predetermined surface roughness; and an anode-side electrode layer that covers the surface are provided.

A capacitor element that has an anode body, a dielectric oxide film layer covering the anode body, and a cathode body formed on the dielectric oxide film layer; an exterior body that covers the capacitor element; a contact layer that is on an anode terminal, which is an end portion of the anode body, and has a surface with a predetermined surface roughness; and an anode-side electrode layer that covers the surface are provided.