Solid electrolytic capacitor

A solid electrolytic capacitor comprising at least one capacitor element,

• the at least one capacitor element including:
• an anode body including a first portion including a first end and a second portion including a second end at a side opposite to the first end, the anode body including a porous part on a surface layer of the anode body;
• a dielectric layer covering at least a part of the anode body;
• a cathode part covering at least a part of the dielectric layer disposed on the second portion;
• and
• a separation part disposed on a part positioned between the first end and the second end of the anode body, the separation part insulating the first portion from the cathode part,
• wherein:
• the cathode part includes at least a conductive polymer layer covering at least the part of the dielectric layer,
• the conductive polymer layer includes an inner layer filled in at least a part of the porous part, and an outer layer positioned outside a principal surface of the anode body including the dielectric layer, the conductive polymer layer including a conductive polymer,
• the separation part includes an end A and an end B, the end B being positioned closer to the second end than the end A is,
• a filling proportion in a region C included in a cross section of a portion of the porous part from the end B to 0.05L is more than or equal to 46%, where L represents a length from the end B to an end of the cathode part at a side close to the second end, and
• the filling proportion is an area proportion of a portion other than voids in the region C.