An example includes a capacitor case sealed to retain electrolyte, at least one anode disposed in the capacitor case, the at least one anode comprising a sintered portion disposed on a substrate, an anode conductor coupled to the substrate in electrical communication with the sintered portion, the anode conductor sealingly extending through the capacitor case to an anode terminal disposed on the exterior of the capacitor case with the anode terminal in electrical communication with the sintered portion, a second electrode disposed in the capacitor case, a separator disposed between the second electrode and the anode and a second electrode terminal disposed on an exterior of the capacitor case and in electrical communication with the second electrode, with the anode terminal and the second electrode terminal electrically isolated from one another.

A method for finely powdering tungsten powder, which includes: a process for classifying a material tungsten powder into a fine powder having a relatively small average particle diameter and a coarse powder having a relatively large average particle diameter; an oxidation process for forming an oxide film on the particle surface of the coarse powder; and an alkali treatment process for removing the oxide film formed in the oxidation process and a natural oxide film formed on the fine powder with an alkali aqueous solution. Also disclosed is a method for producing ultrafine tungsten powder, which includes obtaining tungsten powder having an average particle diameter of 0.04 to 0.4 μm and a BET specific surface area of 5 to 15 m.sup.2/g by the above method for finely powdering.

A solid electrolytic capacitor and method for making the capacitor are provided. The capacitor includes a porous anode body, an anode foil, a dielectric, a cathode, and anode and cathode terminations. The foil is disposed on a planar surface of the anode body, and both comprise a valve metal. Further, the dielectric overlies at least a portion of the anode body, and the dielectric is also formed within the anode body. The cathode overlies at least a portion of the dielectric that overlies the anode body and includes a solid electrolyte, where at least a portion of a lower surface of the foil is free of both the dielectric and the solid electrolyte. In addition, the anode termination is electrically connected to the portion of the lower surface of the foil that is free of both the dielectric and the solid electrolyte, and the cathode termination is electrically connected to the solid electrolyte.

A solid electrolytic capacitor and method for making the capacitor are provided. The capacitor includes a porous anode body, an anode foil, a dielectric, a cathode, and anode and cathode terminations. The foil is disposed on a planar surface of the anode body, and both comprise a valve metal. Further, the dielectric overlies at least a portion of the anode body, and the dielectric is also formed within the anode body. The cathode overlies at least a portion of the dielectric that overlies the anode body and includes a solid electrolyte, where at least a portion of a lower surface of the foil is free of both the dielectric and the solid electrolyte. In addition, the anode termination is electrically connected to the portion of the lower surface of the foil that is free of both the dielectric and the solid electrolyte, and the cathode termination is electrically connected to the solid electrolyte.

To provide an electrolytic capacitor with improved reliability. The electrolytic capacitor including: at least one capacitor element including an anode foil having a first part including a first end, and a second part including a second end, a dielectric layer formed on at least a surface of the second part, and a cathode part covering at least part of the dielectric layer; a package body enclosing the capacitor element; and an external electrode. At least a surface of the second part has a porous portion, and at least an end face of the first end is exposed from the package body and is in contact with the external electrode.

A solid electrolytic capacitor that contains an anode body, dielectric overlying the anode body, adhesion coating overlying the dielectric, and solid electrolyte overlying the adhesion coating. The solid electrolyte contains an inner conductive polymer layer and outer conductive polymer layer, at least one of which is formed from a plurality of pre-polymerized conductive polymer particles. Furthermore, the adhesion coating contains a discontinuous precoat layer containing a plurality of discrete nanoprojections of a manganese oxide (e.g., manganese dioxide).

A capacitor that is capable of exhibiting good electrical properties even under a variety of conditions is provided. More particularly, the capacitor contains a sintered porous anode body, a dielectric that overlies the anode body, and a solid electrolyte that overlies the dielectric. The solid electrolyte contains an inner layer and an outer layer, wherein the inner layer is formed from an in situ-polymerized conductive polymer and the outer layer is formed from pre-polymerized conductive polymer particles. Further, the in-situ polymerized conductive polymer is formed from an alkylated thiophene monomer.

A capacitor that is capable of exhibiting good electrical properties even under a variety of conditions is provided. More particularly, the capacitor contains a sintered porous anode body, a dielectric that overlies the anode body, and a solid electrolyte that overlies the dielectric. The solid electrolyte contains an inner layer and an outer layer, wherein the inner layer is formed from an in situ-polymerized conductive polymer and the outer layer is formed from pre-polymerized conductive polymer particles. Further, the in-situ polymerized conductive polymer is formed from an alkylated thiophene monomer.

An anode for use in a high voltage electrolytic capacitor is provided. The anode contains a sintered porous pellet and a leadwire extending therefrom in a longitudinal direction. The pellet is multi-layered to the extent that it contains at least a first layer positioned adjacent to a second layer, both of which extend along the length of the anode. The anode leadwire is embedded within the first layer. For this reason, the first layer has a thickness greater than that of the leadwire. Nevertheless, the use of a separate and distinct second layer adjacent to the first layer can allow each of the layers to be independently pressed using a multi-sided compaction device so that the properties of the anode are not significantly impacted by the presence of the relatively large anode leadwire.

A Ta-Nb alloy powder which has provides a capacitor having a higher capacitance than a Ta capacitor and a better thermal stability in terms of an oxide film is better than a Nb capacitor, the Ta-Nb alloy powder being a Ta-Nb alloy powder produced by a thermal CVD method, wherein a content of Nb is 1 to 50 mass %, and an average particle diameter of primary particles is 30 to 200 nm, preferably, a CV value per unit mass of the powder (μF.Math.V/g) is 250 kμF.Math.V/g or more, or further, a CV value per unit volume (μF.Math.V/mm.sup.3) in terms of a molded body whose molding density ρ (g/cm.sup.3) is ρ.sub.c (g/cm.sup.3)=−0.012R.sub.Nb+3.57, wherein R.sub.Nb: Nb content (mass %) in an alloy, is 900 μF.Math.V/mm.sup.3 or more, and an anode element for a solid electrolytic capacitor using the alloy powder.