In an embodiment, a capacitor includes a winding element having a diameter of more than 10 mm, at least two tabs electrically contacted with an anode foil and at least two tabs electrically contacted with a cathode foil, wherein the capacitor is a hybrid polymer aluminum electrolytic capacitor, wherein the winding element is arranged inside a can having a can bottom, and wherein the can comprises a corrugation which fixes the winding element.

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.

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 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 disclosed electrolytic capacitor includes a capacitor element. The capacitor element includes an anode body, a dielectric layer formed on a surface of the anode body, a cathode body, and a electrolyte layer and a separator that are disposed between the dielectric layer and the cathode body. The electrolyte layer includes a non-aqueous solvent, conductive particles, and a conductive polymer. An amount of the conductive particles present in a first portion included in the electrolyte layer and located on the dielectric layer side is different from an amount of the conductive particles in a second portion included in the electrolyte layer and located on the cathode body side.

A capacitor has electrode foil (2, 60) and a terminal (tab 4) connected, an etch layer (16) being formed in the electrode foil, wherein a plurality of interrupting parts (12) are included in the etch layer, which is formed in the electrode foil, and at least in a connection part (stitching part 6) at which the terminal is connected. It makes it possible for the electrode foil of a higher capacitance to have flexibility, makes it possible to suppress cracks caused by pressing, and makes it possible to prevent cracks from spreading. In addition, such effects are expected that the electrode foil can be prevented from being damaged in a process of connecting the tab including folding the electrode foil, and pressing raised pieces of the electrode foil and the tab onto the electrode foil.

Provided is a method for producing an electrode for an electrolytic capacitor, the method comprising: a hydration step in which an aluminum electrode is immersed in a hydration treatment solution having a temperature of 80 C. or higher; and a chemical conversion step in which the aluminum electrode is subjected to chemical conversion treatment up to a formation voltage of at least 400 V. The hydration treatment solution contains a hydration inhibitor. The thickness of a hydrated film formed in the hydration step satisfies the following condition, 0.6t2/t11, wherein t1 is the average thickness of the hydrated film formed in a depth range of up to 100 m from the surface of the aluminum electrode, and t2 is the average thickness s of the hydrated film formed in a deep portion at least 100 m from the surface of the aluminum electrode.

A capacitor circuit (capacitor device 20, 30, 34, 50) in which a plurality of capacitors (41 to 45) are connected to each other is included, one or two or more capacitors (overvoltage short-circuiting capacitors 40, 40a, 40b, 40c, 40d) in the capacitor circuit have a dielectric breakdown voltage made lower than that of another capacitor, and the one or two or more capacitors having the lower dielectric breakdown voltage are subjected to dielectric breakdown due to application of an overvoltage earlier than the other capacitor so that the capacitor circuit is short-circuited. As a result, the safety of the capacitor device and a device connected thereto can be enhanced.

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 electrolytic capacitor includes an electrode foil and a lead member connected to the electrode foil. The electrode foil has a first principal surface and a second principal surface opposite to the first principal surface. The electrode foil and the lead member are connected by a caulking part in an overlapping part in which the first principal surface of the electrode foil and the lead member overlap each other. The caulking part has a through-hole penetrating the electrode foil and the lead member. The electrode foil in the caulking part includes a first folded part that is folded back at a peripheral edge portion of the through-hole to be disposed on the second principal surface. The lead member in the caulking part includes (i) a penetrating part that penetrates the electrode foil and (ii) a second folded part that is folded back at an end portion of the penetrating part to be disposed on the second principal surface. The penetrating part includes an inner wall of the through-hole. The second folded part covers the first folded part.