Abstract: A method of processing a metal foil to produce a cathode for an electrolytic capacitor includes printing one or more layers of conductive ink on the metal foil to form a pattern of cathode plates, each of the one or more layers being a predetermined thickness, and the pattern arranged at a distance from a cathode tab and an edge of the cathode plates. The method also includes heating the deposited one or more layers of conductive ink to evaporate a solvent within the conductive ink such that conductive particles of the conductive ink remain deposited on the metal foil. The method further includes sintering the conductive particles and cutting the cathode plates from the metal foil, thereby producing the cathode plates suitable for use in the electrolytic capacitor.

Abstract: Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a persulfate, a halide, an oxidizing agent, and a sulfate. An etch resist can be added to the anode foil prior to etching. The anode foil and the attached etch resist can be heated prior to immersing both in an electrolyte bath composition. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath, while maintaining a constant level of persulfate. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: A cathode subassembly for use in an electrolytic capacitor may include a first separator sheet including a surface having first and second regions, where the second region extends from a perimeter of the first region to a first peripheral edge of the first sheet, a second peripheral edge of a second sheet is substantially aligned with the first peripheral edge, a conductive foil is sandwiched between the first and second sheets and disposed within the first region, the first and second sheets are adhered to each other in a sealing region extending from the second region to a region of a surface of the second sheet facing the second region, and the first sheet includes at least one first recessed portion at the first peripheral edge aligned with at least one second recessed portion at the second peripheral edge of the second sheet.

Abstract: Fabricating a capacitor includes obtaining a sheet of material having a first phase of an anode metal oxide on an anode metal. The anode metal oxide is an oxide of the anode metal. A portion of the first phase of the anode metal oxide is converted to a second phase of the anode metal oxide. At least a portion of the second phase of the anode metal oxide is removed from the sheet of material. In some instances, the first phase of the anode metal is converted to the second phase of the anode metal oxide as a result of the process used to extract a capacitor anode from the sheet of material.

Abstract: A capacitor and methods of processing an anode metal foil are presented. The capacitor includes a housing, one or more anodes disposed within the housing, one or more cathodes disposed within the housing, one or more separators disposed between an adjacent anode and cathode, and an electrolyte disposed around the one or more anodes, one or more cathodes, and one or more separators within the housing. The one or more anodes each include a metal foil that includes a first plurality of tunnels through a thickness of the metal foil in a first ordered arrangement, the first ordered arrangement being a close packed hexagonal array arrangement, and having a first diameter, and a second plurality of tunnels through the thickness of the metal foil having a second ordered arrangement and a second diameter greater than the first diameter.

Abstract: Fabricating a capacitor includes forming conduits in a porous layer of material. The porous layer of material has particles that each includes a dielectric on a core. The formation of the conduits causes a portion of the dielectric to convert from a first phase to a second phase. The method also includes removing at least a portion of the second phase of the dielectric from the porous layer of material.

Abstract: Designs of a capacitor housing and method of assembly are presented. A case for an electrolytic capacitor includes a non-conducting cover, a non-conducting ring component, and a non-conducting plate. The non-conducting cover has a patterned groove on a surface of the non-conducting cover. The non-conducting ring component has a shape that is substantially the same as a shape of the non-conducting cover, and is coupled to the non-conducting cover via the patterned groove of the non-conducting cover. The non-conducting plate has a shape that is substantially the same as the shape of the non-conducting cover, and has a patterned groove on a surface of the non-conducting plate. The non-conducting ring component is coupled to the non-conducting plate via the groove of the non-conducting plate.

Abstract: The present invention is directed to a method of etching anode foil in a non-uniform manner which minimizes thermal oxidation during foil cutting. Having less oxide improves the ability to cut through aluminum anodes with lower energy rates. In aluminum foils, it has been found that a masking step before etching reduces conversion of boehmite aluminum oxide to alpha-phase corundum during laser cutting of anodes, which increases edge quality and productivity. Additionally, the non-etched anode frame allows for less surface area to form during the aging process. As a result, the leakage current is reduced by the proportion of edge to anode surface area, and the aging process will be faster, leading to higher productivity.

Abstract: Fabricating a capacitor includes performing an oxide formation operation on a sheet of material. The oxide formation operation forms an anode metal oxide on an anode metal. A thermal compression is performed on the sheet of material after the oxide formation operation is performed. The thermal compression applies thermal energy to the sheet of material while applying pressure to the sheet of material. After the thermal compression, the capacitor is assembled such that at least one electrode in the capacitor includes at least a portion of the sheet of material.

Abstract: Fabricating a capacitor includes obtaining a sheet of material having a first phase of an anode metal oxide on an anode metal. The anode metal oxide is an oxide of the anode metal. A portion of the first phase of the anode metal oxide is converted to a second phase of the anode metal oxide. At least a portion of the second phase of the anode metal oxide is removed from the sheet of material. In some instances, the first phase of the anode metal is converted to the second phase of the anode metal oxide as a result of the process used to extract a capacitor anode from the sheet of material.

Abstract: A method of producing an electrode for use in the manufacture of electrolytic capacitors for implantable cardioverter defibrillators comprises first growing a hydrate layer and/or formed oxide layers of the foil, applying a laser beam to portions of the foil to ablate the aluminum oxide foil surface before etching in order to induce etching in the specific areas, and then, etching the foil. The laser marks the oxide layer in a pulsed spot pattern through the hydrate layer and/or formed oxide layer leaving a dimpled nascent aluminum surface. The oxide layer left behind is a mask and the fresh aluminum areas are the high etching activation sites. After marking the aluminum oxide foil surface, the foil may be electrochemically etched in an electrolyte containing chloride and/or various oxidative species.

Abstract: The present invention is directed to a method of etching anode foil in a non-uniform manner which minimizes thermal oxidation during foil cutting. Having less oxide improves the ability to cut through aluminum anodes with lower energy rates. In aluminum foils, it has been found that a masking step before etching reduces conversion of boehmite aluminum oxide to alpha-phase corundum during laser cutting of anodes, which increases edge quality and productivity. Additionally, the non-etched anode frame allows for less surface area to form during the aging process. As a result, the leakage current is reduced by the proportion of edge to anode surface area, and the aging process will be faster, leading to higher productivity.

Abstract: A process and apparatus are presented for cleaning the tunnels of an electrochemically etched anode foil. The apparatus includes a tank, a fluid inlet and a fluid outlet, and one or more tranducers. The tank is designed to receive a plurality of cartridges, each of the plurality of cartridges having a reservoir and being designed to hold a metal foil. The fluid inlet and fluid outlet are coupled with at least one of the plurality of cartridges, and are designed to introduce and expel, respectively, a liquid from the reservoir within at least one of the plurality of cartridges. The one or more transducers are coupled to at least one wall of each reservoir, the one or more transducers being designed to sonicate the liquid within each reservoir at a frequency less than 300 Hz.

Abstract: A capacitor and a method of processing an anode metal foil are presented. The method includes electrochemically etching the metal foil to form a plurality of tunnels. Next, the etched metal foil is disposed within a widening solution to widen the plurality of tunnels. Exposed surfaces of the etched metal foil are then oxidized. The method includes removing a section of the etched metal foil, where the section of the etched metal foil includes exposed metal along an edge. The section of the etched metal foil is placed into a bath comprising water to form a hydration layer over the exposed metal on the section of the etched metal foil. The method also includes assembling the section of the etched metal foil having the hydration layer as an anode within a capacitor.

Abstract: Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a persulfate, a halide, an oxidizing agent, and a sulfate. An etch resist can be added to the anode foil prior to etching. The anode foil and the attached etch resist can be heated prior to immersing both in an electrolyte bath composition. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath, while maintaining a constant level of persulfate. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: A process and apparatus are presented for cleaning the tunnels of an electrochemically etched anode foil. The apparatus includes a tank, a fluid inlet and a fluid outlet, and one or more tranducers. The tank is designed to receive a plurality of cartridges, each of the plurality of cartridges having a reservoir and being designed to hold a metal foil. The fluid inlet and fluid outlet are coupled with at least one of the plurality of cartridges, and are designed to introduce and expel, respectively, a liquid from the reservoir within at least one of the plurality of cartridges. The one or more transducers are coupled to at least one wall of each reservoir, the one or more transducers being designed to sonicate the liquid within each reservoir at a frequency less than 300 Hz.

Abstract: A capacitor and a method of processing an anode metal foil are presented. The method includes electrochemically etching the metal foil to form a plurality of tunnels. Next, the etched metal foil is disposed within a widening solution to widen the plurality of tunnels. Exposed surfaces of the etched metal foil are then oxidized. The method includes removing a section of the etched metal foil, where the section of the etched metal foil includes exposed metal along an edge. The section of the etched metal foil is placed into a bath comprising water to form a hydration layer over the exposed metal on the section of the etched metal foil. The method also includes assembling the section of the etched metal foil having the hydration layer as an anode within a capacitor.

Abstract: A method for patterning a metal substrate includes a series of surface treatments to control tunnel initiation at a micron or sub-micron level. In particular, the series of surface treatments include forming a hydration layer which acts as a mask while etching the surface of the metal substrate. The hydration layer mask enables control of the tunnel initiation on a micron or sub-micron level because the etching does not undercut the interface between the metal substrate and the hydration layer. As a result, the tunnels can be initiated in an orthogonal direction and closer together, thereby increasing the tunnel density.

Abstract: Methods are presented that includes replacing oven depolarization of a foil with a sonic vibration process for stressing the oxide. The method includes electrochemically etching the metal foil to form a plurality of tunnels in the metal foil and forming an oxide on a surface of the metal foil. The method further includes applying sonic vibration to the metal foil to induce stress fractures in the oxide, and reforming the oxide to heal at least a portion of the stress fractures.

Abstract: A capacitor and methods of processing an anode metal foil are presented. The capacitor includes a housing, one or more anodes disposed within the housing, one or more cathodes disposed within the housing, one or more separators disposed between an adjacent anode and cathode, and an electrolyte disposed around the one or more anodes, one or more cathodes, and one or more separators within the housing. The one or more anodes each include a metal foil that includes a first plurality of tunnels through a thickness of the metal foil in a first ordered arrangement, the first ordered arrangement being a close packed hexagonal array arrangement, and having a first diameter, and a second plurality of tunnels through the thickness of the metal foil having a second ordered arrangement and a second diameter greater than the first diameter.