Solid electrolytic capacitor element, solid electrolytic capacitor, and method for manufacturing solid electrolytic capacitor element

A method for producing a solid electrolytic capacitor element,

• the solid electrolytic capacitor element including:
• an anode body that includes a porous portion at least at a surface layer of the anode body;
• a dielectric layer formed on at least a portion of a surface of the porous portion;
• and a cathode portion that includes a solid electrolyte layer that covers at least a portion of the dielectric layer and a cathode lead-out layer that covers at least a portion of the solid electrolyte layer,
• the method comprising:
• a first step of preparing the anode body having the dielectric layer on the surface of the porous portion;
• a second step of forming the solid electrolyte layer to cover at least the portion of the dielectric layer;
• and
• a third step of forming the cathode lead-out layer to cover at least the portion of the solid electrolyte layer,
• wherein the second step includes:
• a first sub-step of forming a first solid electrolyte that covers at least a portion of the dielectric layer using a first treatment solution that contains a self-doped conductive polymer;
• a second sub-step of forming a solid electrolyte 2A that covers at least a portion of the first solid electrolyte using a liquid dispersion 2A that contains a conductive polymer 2A;
• a third sub-step of forming a solid electrolyte 2B that covers at least a portion of the solid electrolyte 2A using a liquid dispersion 2B that contains a conductive polymer 2B;
• and
• a fourth sub-step of forming a solid electrolyte 2C that covers at least a portion of the solid electrolyte 2B using a liquid dispersion 2C that contains a conductive polymer 2C,
• the second step also includes at least one of:
• a fifth sub-step of applying a second treatment solution that contains an ionic liquid to a surface of the solid electrolyte 2A and drying the second treatment solution, performed between the second sub-step and the third sub-step;
• and
• a sixth sub-step of applying a third treatment solution that contains an ionic liquid to a surface of the solid electrolyte 2B and drying the third treatment solution, performed between the third sub-step and the fourth sub-step, and
• in the solid electrolytic capacitor element, out of a first interface between the first solid electrolyte and the solid electrolyte 2A, a second interface between the solid electrolyte 2A and the solid electrolyte 2B, a third interface between the solid electrolyte 2B and the solid electrolyte 2C, and a fourth interface between the solid electrolyte 2C and the cathode lead-out layer, the second interface or the third interface has a largest distribution amount of the ionic liquid.