Avx Corporation

Zebbie Lynn Sebald

James Allen Fife

Gang Ning

Bharat Rawal

Stanislav Zednicek

Mitchell D Weaver

Dirk H Dreissig

Brady A Jones

James Steven Bates

Zdenek Sita

Robert Hazen Pease

Andrew Paul Ritter

John L Galvagni

Martin Biler

Frantisek Priban

A wet electrolytic capacitor that contains electrodes (i.e., anode and cathode) and a working electrolyte is provided. The anode and optionally the cathode include a wire assembly containing two or more individual wires. A particulate material is also disposed in contact with at least a portion of the wire assembly.

Wet electrolytic capacitor

A wet electrolytic capacitor is provided. The capacitor contains an anode comprising an anodically oxidized pellet formed from a pressed and sintered powder, a cathode that contains a metal substrate coated with a conductive polymer, and a working electrolyte in communication with the anode and the cathode. The working electrolyte is in the form of a gel and comprises an ammonium salt of an organic acid, inorganic oxide particles, an acid, and a solvent system that comprises water. The working electrolyte has a pH value of from about 5.0 to about 8.0.

Wet electrolytic capacitor containing a gelled working electrolyte

A wet electrolytic capacitor that includes a porous anode body containing a dielectric layer, an electrolyte, and a cathode containing a metal substrate that is abrasive blasted is provided. Abrasive blasting may accomplish a variety of different purposes. For example, it may result in a surface that is substantially uniform and macroscopically smooth, thereby increasing the consistency of conductive coatings formed thereon. While possessing a certain degree of smoothness, the abrasive blasted surface is nevertheless micro-roughened so that it contains a plurality of pits. The pits provide an increased surface area, thereby allowing for increased cathode capacitance for a given size and/or capacitors with a reduced size for a given capacitance. A conductive coating that contains a substituted polythiophene is disposed on the micro-roughened surface. The presence of the pits on the substrate enhances the degree of contact between the conductive coating and metal substrate, thereby resulting in improved mechanical robustness and electrical performance (e.g., reduced equivalent series resistance and leakage current).

Abrasive blasted conductive polymer cathode for use in a wet electrolytic capacitor

A capacitor assembly that includes a conductive polymer electrolytic capacitor that is enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas is provided. Without intending to be limited by theory, the present inventors believe that the ceramic housing is capable of limiting the amount of oxygen and moisture supplied to the conductive polymer of the capacitor. In this manner, the conductive polymer is less likely to oxidize in high temperature environments, thus increasing the thermal stability of the capacitor assembly.

Hermetically sealed capacitor assembly

A capacitor anode that is formed from flake powder is provided. The anodes are formed from low density flake powder (e.g., relatively large in size), which is believed to provide a short transmission line between the outer surface and interior of the anode. This may result in a low equivalent series resistance ('ESR') and improved volumetric efficiency for capacitors made from such anodes.

Capacitor anode formed from flake powder

A porous substrate for use in a wide variety of applications, such as wet capacitors, is provided. The substrate is formed by subjecting a metal substrate to a voltage while in solution to initiate anodic formation of an oxide film. Contrary to conventional anodization processes, however, the newly created oxide quickly breaks down to once again expose the metal surface to the electrolytic solution. This may be accomplished in a variety of ways, such as by raising the voltage of the solution above a critical level known as the 'breakdown voltage', employing a corrosive acid in the solution that dissolves the oxide, etc. Regardless of the mechanism employed, the nearly simultaneous process of oxide growth/breakdown results in the formation of a structure having pores arranged at substantially regular intervals. The resulting structure is highly porous and can exhibit excellent adhesion to electrochemically-active materials and stability in aqueous electrolytes.

Substrate for use in wet capacitors

A wet electrolytic capacitor that includes an anode, cathode, and an electrolyte is provided. The cathode contains a substrate and a coating overlying the substrate. The coating comprises a sintered body containing carbonaceous particles (e.g., activated carbon) and inorganic particles (e.g., NbO).

Wet electrolytic capacitor containing a cathode coating

A wet electrolytic capacitor that includes an anode, cathode, and an electrolyte is provided. The cathode contains a plurality of metal particles disposed on a surface of a substrate and sinter bonded thereto. The metal particles have a median size of from about 20 to about 500 micrometers.

A solid electrolytic capacitor that comprises an anode that contains a valve-action metal (e.g., tantalum, niobium, and the like) and a dielectric film overlying the anode is provided. The capacitor also comprises a protective coating overlying the dielectric film, wherein the protective coating contains a relatively insulative, resinous material. For example, in one embodiment, the resinous material can be a drying oil, such as olive oil, linseed oil, tung oil, castor oil, soybean oil, shellac, and derivatives thereof. The capacitor also comprises a conductive polymer coating overlying the protective coating. As a result of the present invention, it has been discovered that a capacitor can be formed that can have a relatively low leakage current, dissipation factor, and equivalents series resistance.

Protective coating for electrolytic capacitors

A solid electrolytic capacitor having an anode that contains a valve-action metal (e.g., tantalum, niobium, and the like) and a dielectric film overlying the anode is provided. The capacitor also include a protective coating overlying the dielectric film, wherein the protective coating contains a relatively insulative, resinous material. For example, in one embodiment, the resinous material can be a drying oil, such as olive oil, linseed oil, tung oil, castor oil, soybean oil, shellac, and derivatives thereof. The capacitor also includes a conductive polymer coating overlying the protective coating. As a result of the present invention, it has been discovered that a capacitor can be formed that can have a relatively low leakage current, dissipation factor, and equivalents series resistance.

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Myrtle Beach, SC, United States of America

Zebbie Lynn Sebald