A solid electrolytic capacitor (1) includes an anode foil (2a) having formed thereon an oxide film, a cathode foil (2c), and a separator (2d), and is equipped with a solid electrolyte (20) formed of an electroconductive polymer compound in a fine particle form, and a water-soluble compound solution (30) introduced to surround the solid electrolyte (20), the solid electrolyte (20) contains a polyol compound having a molecular weight of less than 200 and a number of hydroxy groups of 4 or more as a first water-soluble compound (2f1), the water-soluble compound solution (30) contains one kind or multiple kinds of a glycol compound in a liquid form as a second water-soluble compound (2f2), and the second water-soluble compound (2f2) has an average molecular weight of less than 400.

A winding type capacitor assembly with enhanced structural strength and a manufacturing method thereof are provided. The winding type capacitor assembly includes a positive conductive foil, a negative conductive foil, and at least one isolation element. The isolation element is disposed between the positive conductive foil and the negative conductive foil. A conductive polymer dispersed sol and an electrolyte filler are disposed between the positive conductive foil, the negative conductive foil, and the isolation element. The electrolyte filler is at least one selected from one of a conductive composition synthesized by a chemical polymerization method and a resin-blended conductive particle. The winding type capacitor assembly has enhanced structural strength through the use of the electrolyte filler.

An electrode body which achieves not only high initial capacitance of an electrolyte capacitor but also achieves stable capacitance even after being exposed to high temperature environment, and the electrolyte capacitor including the electrode body are provided. The electrode body is used for a negative electrode of the electrolyte capacitor, and the electrode body includes a negative electrode foil formed by a valve action metal, and a carbon layer formed on the negative electrode foil. The carbon layer includes a first spherical carbon and a second spherical carbon, and the first spherical carbon has a BET specific surface area larger than the second spherical carbon.

An electrode foil for an electrolytic capacitor includes: an anode body including a first metal; a first dielectric layer covering at least a part of the anode body and including an oxide of the first metal; and a second dielectric layer covering at least a part of the first dielectric layer and including an oxide of a second metal. The first metal includes at least one selected from the group consisting of titanium, tantalum, niobium, and aluminum. And the second metal includes at least one selected from the group consisting of silicon, zirconium, hafnium, and tantalum. A thickness T2 of the second dielectric layer is smaller than a thickness T1 of the first dielectric layer.

An electrolytic capacitor includes a capacitor element, a body case, and a sealing body. The capacitor element has a cathode foil and an anode foil wound up with a separator in between, and has a prescribed solution held between the cathode foil and the anode foil. The body case houses the capacitor element. The sealing body seals the body case. The solution is a fat-soluble antioxidant dissolved in a lypophilic solvent and the separator is configured to be in contact with the sealing body.

A cathode foil for electrolytic capacitors includes a metal porous part, a metal core part that is continuous with the metal porous part, and a coating film covering the metal porous part. Pores in the metal porous part are open at a first main surface of the cathode foil. The coating film is disposed in a region from the first main surface to a depth more than or equal to 10% of a thickness of the metal porous part in a thickness direction of the metal porous part.

An electrolytic capacitor includes a capacitor element and an electrolytic solution. The capacitor element includes: an anode body including a dielectric layer; a cathode body; and a solid electrolyte in contact with the dielectric layer. The electrolytic solution includes a solvent, a solute, and a polymer component. The solvent includes an ethylene glycol compound. The polymer component includes polyalkylene glycol. The polyalkylene glycol includes at least one of (i) a mixture of polyoxyethylene and polyoxypropylene and (ii) an oxyethylene-oxypropylene copolymer. In the polyalkylene glycol, a molar ratio m/n of oxyethylene units to oxypropylene units is greater than 1.

A method for manufacturing a polymer capacitor and a polymer capacitor are disclosed. In an embodiment a method for manufacturing a polymer capacitor includes winding an anode foil, a cathode foil and separator foils to form a winding, impregnating the winding with a dispersion comprising a solvent and a polymer precursor and extracting the solvent from the winding by supercritical fluid extraction.

An electrolytic capacitor includes a capacitor element and an electrolytic solution. The capacitor element includes: an anode body including a dielectric layer; a cathode body; and a solid electrolyte in contact with the dielectric layer. The electrolytic solution includes a solvent, a solute, and a polymer component. The solvent includes an ethylene glycol compound. The polymer component includes polyalkylene glycol. The polyalkylene glycol includes at least one of (i) a mixture of polyoxyethylene and polyoxypropylene and (ii) an oxyethylene-oxypropylene copolymer. In the polyalkylene glycol, a molar ratio m/n of oxyethylene units to oxypropylene units is greater than 1.

A method for producing an electrolytic capacitor, the method including steps of: preparing an electrode foil; preparing a first conductive polymer dispersion containing a first conductive polymer component and a first dispersion medium; forming a first conductive polymer layer containing the first conductive polymer component, by applying the first conductive polymer dispersion to a surface of the electrode foil by a coating method, and then at least partially removing the first dispersion medium; and fabricating a capacitor element, using the electrode foil having the first conductive polymer layer.