Abstract: A solid electrolytic capacitor includes an element stack, an anode terminal, a cathode terminal, and an exterior member. The element stack includes a plurality of capacitor elements stacked on each other, and a conductive material interposed between two adjacent capacitor elements in the plurality of capacitor elements. Each of the plurality of capacitor elements includes an anode part and a cathode part, and the conductive material is disposed on the cathode part. The anode terminal is connected to the anode part. The cathode terminal is connected to the cathode part via a conductive paste. The cathode terminal has a facing surface facing a tip end of the element stack with a gap interposed between the facing surface and the tip end, and at least a part of the gap is filled with a sealing material.

Abstract: A solid electrolytic capacitor element includes an anode foil that includes a porous part in a surface layer of the anode foil, a dielectric layer,and a cathode part. The cathode part includes a solid electrolyte layer that covers the at least a part of the dielectric layer and a cathode lead-out layer that covers at least a part of the solid electrolyte layer. The anode foil includes a first part that is a cathode forming part where the solid electrolyte layer is formed and a second part where the solid electrolyte layer is not formed. And the anode foil includes a dense part in the surface layer in at least one of the first part and the second part. The dense part has a porosity smaller than a porosity of the porous part. The second part includes at least an anode part including an end part of the anode foil opposite to the first part.