A wet tantalum electrolytic capacitor containing a cathode, fluidic working electrolyte, and anode formed from an anodically oxidized sintered porous tantalum pellet is described. The pellet is formed from a pressed tantalum powder. The tantalum powder is formed by reacting a tantalum oxide compound, for example, tantalum pentoxide, with a reducing agent that contains a metal having an oxidation state of 2 or more, for example, magnesium. The resulting tantalum powder is nodular or angular and has a specific charge that ranges from about 9,000 μF*V/g to about 11,000 μF*V/g. Using this powder, wet tantalum electrolytic capacitors have breakdown voltages that ranges from about 340 volts to about 450 volts. This makes the electrolytic capacitors ideal for use in an implantable medical device.

A method for producing an electrode for an electrolytic capacitor, the method including: a chemical conversion step of allowing a current to flow through a metal material containing a valve metal in a chemical conversion solution containing an electrolyte, to form an oxide film on a surface of the metal material, wherein the chemical conversion solution contains a nitrate-based compound as the electrolyte at a concentration of 0.03 mass % or more, and a phosphorus compound concentration in the chemical conversion solution is less than 0 01 mass %.

In a solid electrolytic capacitor having an electrolyte layer consisting of a solid electrolyte layer and a liquid, the solid electrolytic capacitor, which suppresses a dedoping reaction and which ESR thereof does not keenly increase, in particular, after a loading of heat stress, is provided. In the solid electrolytic capacitor, the electrolyte layer is formed in the capacitor element which is formed by opposing an anode foil and a cathode foil. This electrolyte layer includes the solid electrolyte layer and the liquid. The solid electrolyte layer includes a conductive polymer consisting of a dopant and a conjugated polymer. The liquid is filled in air gaps in the capacitor element on which the solid electrolyte layer is formed. The electrolyte layer includes ammonia as a cation component, and a molecular ratio of the cation component relative to 1 mol of a functional group which can contribute to a doping reaction of the dopant, in the electrolyte layer is 23 or less.

In a solid electrolytic capacitor having an electrolyte layer consisting of a solid electrolyte layer and a liquid, the solid electrolytic capacitor, which suppresses a dedoping reaction and which ESR thereof does not keenly increase, in particular, after a loading of heat stress, is provided. In the solid electrolytic capacitor, the electrolyte layer is formed in the capacitor element which is formed by opposing an anode foil and a cathode foil. This electrolyte layer includes the solid electrolyte layer and the liquid. The solid electrolyte layer includes a conductive polymer consisting of a dopant and a conjugated polymer. The liquid is filled in air gaps in the capacitor element on which the solid electrolyte layer is formed. The electrolyte layer includes ammonia as a cation component, and a molecular ratio of the cation component relative to 1 mol of a functional group which can contribute to a doping reaction of the dopant, in the electrolyte layer is 23 or less.

An electrolytic capacitor includes a capacitor element that includes a porous anode body including an anode base body and a dielectric layer formed on a surface of the anode base body, and a solid electrolyte layer that covers at least a part of the dielectric layer. The anode body includes a plurality of principal surfaces, and at least a part of a surface layer of at least one principal surface of the plurality of principal surfaces of the anode body is denser than an inside of the anode body.

An electrolytic capacitor includes a capacitor element that includes a porous anode body including an anode base body and a dielectric layer formed on a surface of the anode base body, and a solid electrolyte layer that covers at least a part of the dielectric layer. The anode body includes a plurality of principal surfaces, and at least a part of a surface layer of at least one principal surface of the plurality of principal surfaces of the anode body is denser than an inside of the anode body.

A wet electrolytic capacitor that contains a casing that contains a cylindrical sidewall is provided. The cylindrical sidewall defines an inner surface that surrounds an interior. First and second outer anodes are positioned within the interior of the casing. The first outer anode has a radiused sidewall and an opposing planar sidewall and the second outer anode has a radiused sidewall and an opposing planar sidewall. A central anode is also positioned within the interior of the casing between the first and second outer anodes. The central anode contains opposing first and second outer sidewalls intersecting with opposing first and second inner sidewalls. The first and second inner sidewalls are planar, and the first planar inner sidewall of the central anode faces the planar sidewall of the first outer anode and the second planar inner sidewall of the central anode faces the planar sidewall of the second outer anode.

A wet electrolytic capacitor that contains a casing that contains a sidewall extending to an upper end to define an opening is provided. The sidewall further defines an inner surface that surrounds an interior. At least one anode and at least one cathode are positioned within the interior of the casing, wherein the cathode contains an electrochemically-active material and further wherein an anode lead extends from the anode. A working electrolyte is in electrical contact with the anode and the electrochemically-active material. The capacitor also comprises a lid assembly that contains a lid positioned on an upper end of the casing sidewall, wherein the lid defines an orifice through which a tube extends. The tube accommodates the anode lead that extends from the anode. A dielectric layer is formed on a surface of the tube.

A wet electrolytic capacitor that contains a casing that contains a sidewall extending to an upper end to define an opening is provided. The sidewall further defines an inner surface that surrounds an interior. At least one anode and at least one cathode are positioned within the interior of the casing, wherein the cathode contains an electrochemically-active material and further wherein an anode lead extends from the anode. A working electrolyte is in electrical contact with the anode and the electrochemically-active material. The capacitor also comprises a lid assembly that contains a lid positioned on an upper end of the casing sidewall, wherein the lid defines an orifice through which a tube extends. The tube accommodates the anode lead that extends from the anode. A dielectric layer is formed on a surface of the tube.

A composite electronic component includes a composite body having a multilayer ceramic capacitor and a tantalum capacitor coupled to each other, so as to have an excellent acoustic noise reduction effect, a low equivalent series resistance (ESR)/equivalent series inductance (ESL), improved direct current (DC)-bias characteristics, and a low chip thickness.