An electrolytic capacitor includes a capacitor element, an exterior body , a first external electrode, and a second external electrode. The capacitor element includes an anode body that is electrically connected to the first external electrode and has a porous part on a surface thereof, a dielectric layer that is disposed on a surface of at least a part of the porous part, and a solid electrolyte layer that covers at least a part of the dielectric layer, and is electrically connected to the second external electrode. The exterior body has a first principal surface, a second principal surface intersecting the first principal surface, a third principal surface opposite to the first principal surface, and a fourth principal surface opposite to the second principal surface. The first external electrode and the second external electrode are disposed along the first principal surface of the exterior body to be separated from each other.

An electrolytic capacitor includes a capacitor element, an exterior body , a first external electrode, and a second external electrode. The capacitor element includes an anode body that is electrically connected to the first external electrode and has a porous part on a surface thereof, a dielectric layer that is disposed on a surface of at least a part of the porous part, and a solid electrolyte layer that covers at least a part of the dielectric layer, and is electrically connected to the second external electrode. The exterior body has a first principal surface, a second principal surface intersecting the first principal surface, a third principal surface opposite to the first principal surface, and a fourth principal surface opposite to the second principal surface. The first external electrode and the second external electrode are disposed along the first principal surface of the exterior body to be separated from each other.

An electronic component including a base body including a first end surface and a second end surface opposite to each other in a length direction, a first internal electrode exposed at the first end surface, and a second internal electrode exposed at the second end surface; a first external electrode on the first end surface and connected to the first internal electrode; and a second external electrode on the second end surface and connected to the second internal electrode. The first external electrode includes a resin electrode layer containing a conductive component and a resin component, the resin electrode layer of the first external electrode includes a first portion facing a whole surface of the first end surface of the base body, and a plurality of protrusions are arranged periodically side by side on a surface of the first portion of the resin electrode layer of the first external electrode.

An electronic component including a base body including a first end surface and a second end surface opposite to each other in a length direction, a first internal electrode exposed at the first end surface, and a second internal electrode exposed at the second end surface; a first external electrode on the first end surface and connected to the first internal electrode; and a second external electrode on the second end surface and connected to the second internal electrode. The first external electrode includes a resin electrode layer containing a conductive component and a resin component, the resin electrode layer of the first external electrode includes a first portion facing a whole surface of the first end surface of the base body, and a plurality of protrusions are arranged periodically side by side on a surface of the first portion of the resin electrode layer of the first external electrode.

A solid electrolytic capacitor that includes: a valve-action metal substrate including a porous portion at a surface thereof; a dielectric layer on the porous portion; a solid electrolyte layer on the dielectric layer; a conductive layer on the solid electrolyte layer; and a cathode lead-out layer on the conductive layer. When viewed in a thickness direction, the solid electrolyte layer includes a central region at a center of the solid electrolyte layer and a peripheral region surrounding the central region and defining outer edges of the solid electrolyte layer. The peripheral region is higher than the central region in the thickness direction as measured from a reference surface including a highest point of the porous portion in the thickness direction and perpendicular to the thickness direction. The conductive layer is at least on the central region of the solid electrolyte layer.

A solid electrolytic capacitor that includes: a valve-action metal substrate including a porous portion at a surface thereof; a dielectric layer on the porous portion; a solid electrolyte layer on the dielectric layer; a conductive layer on the solid electrolyte layer; and a cathode lead-out layer on the conductive layer. When viewed in a thickness direction, the solid electrolyte layer includes a central region at a center of the solid electrolyte layer and a peripheral region surrounding the central region and defining outer edges of the solid electrolyte layer. The peripheral region is higher than the central region in the thickness direction as measured from a reference surface including a highest point of the porous portion in the thickness direction and perpendicular to the thickness direction. The conductive layer is at least on the central region of the solid electrolyte layer.

An electrolytic capacitor includes exterior body and an element stack body including a plurality of capacitor elements. Each of the plurality of capacitor elements includes an anode body, a dielectric layer, and a cathode part covering at least a part of the dielectric layer. The exterior body includes a first principal surface, a second principal surface intersecting the first principal surface, a third principal surface opposite to the first principal surface, and a fourth principal surface opposite to the second principal surface. In at least one first capacitor element among the plurality of capacitor elements, an end surface of an end of the anode body is exposed from the exterior body at least on first principal surface to be electrically connected to a first external electrode. And an end surface of an end of the cathode part is exposed from the exterior body at least on second principal surface to be electrically connected to a second external electrode.

An electricity storage device includes: an electrode group including first and second electrodes; a case accommodating the electrode group therein, the case having an opening provided therein; and a sealing body covering the opening of the case. The case includes a tubular part, a curved part connected to one end of the tubular part, and a bottom part closing another end of the tubular part. The curved part includes an opening rim, a crimp part connected to the opening rim, and a groove part connected to the crimp part, the crimp part being located outward from the opening rim along a radial direction of the tubular part, the groove part being recessed to protrude inward in the radial direction of the tubular part and having an annular shape. The sealing body includes: a sealing plate having conductivity; and a gasket having electric insulation, the gasket being compressed between the sealing plate and a portion of the crimp part facing the groove part and between the sealing plate and an inner surface of the groove part. The case is electrically connected to the first electrode. The sealing plate is electrically connected to the second electrode. The opening rim does not contact the gasket.

A capacitor 1 includes a capacitor element 3 holding solution between an anode foil 5 and a cathode foil 7 that are wound up with a separator 6 in between, a body case 2 for housing the capacitor element 3, and a sealing member 4 for sealing the body case 2. A part of the separator 6 makes contact, at a plurality of points or over an area, with the face of the sealing member 4 facing the capacitor element 3 so as to rest on that face. The solution contains, dissolved in a lipophilic solvent, deterioration preventing agent that solidifies by oxidation. The solution is supplied through the separator 6 to the sealing member 4 and permeates the sealing member 4, so that a coating 17 resulting from the agent solidifying coats the outer face of the sealing member 4, leaving the solution present in the sealing member 4.

A capacitor 1 includes a capacitor element 3 holding solution between an anode foil 5 and a cathode foil 7 that are wound up with a separator 6 in between, a body case 2 for housing the capacitor element 3, and a sealing member 4 for sealing the body case 2. A part of the separator 6 makes contact, at a plurality of points or over an area, with the face of the sealing member 4 facing the capacitor element 3 so as to rest on that face. The solution contains, dissolved in a lipophilic solvent, deterioration preventing agent that solidifies by oxidation. The solution is supplied through the separator 6 to the sealing member 4 and permeates the sealing member 4, so that a coating 17 resulting from the agent solidifying coats the outer face of the sealing member 4, leaving the solution present in the sealing member 4.