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 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 sulfate, a halide, an oxidizing agent, and a surface active agent. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: Device designs are presented that include a cathode subassembly for protecting the device from unwanted discharge, and aiding in alignment of the cathodes and anodes within a device. A device includes a conductive anode, a dielectric material disposed on a surface of the conductive anode, a conductive cathode, and an electrolyte disposed between the anode and the cathode. The conductive cathode is sandwiched between two separator sheets, the two separator sheets being adhered together at a peripheral edge in an area outside of a perimeter of the conductive cathode.

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: Anode foils suitable for use in electrolytic capacitors, including those having multiple anode configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include disposing a resist material in a predetermined pattern on an exposed surface of an anode foil substrate such that a first portion of the exposed surface of the anode foil substrate is covered by the resist material, and a second portion of the exposed surface remains uncovered; polymerizing the resist material; exposing at least the second portion of the exposed surface to one or more etchants so as to form a plurality of tunnels; stripping the polymerized resist material; and widening at least a portion of the plurality of tunnels. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing.

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: 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: Electrode foils suitable for use in electrolytic capacitors, including those having multiple configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include forming a pattern of etch resist on a surface of a substrate; etching a first area of the surface substantially enclosed by the pattern and a second area in intervals between the pattern to form tunnels in first and second areas of the surface; and removing the resist material revealing a non-etched frame. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing. Additionally, an etch resist pattern may be used to form strength lines on the substrate surface.

Abstract: Electrode foils suitable for use in electrolytic capacitors, including those having multiple configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include forming a pattern of etch resist on a surface of a substrate; etching a first area of the surface substantially enclosed by the pattern and a second area in intervals between the pattern to form tunnels in first and second areas of the surface; and removing the resist material revealing a non-etched frame. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing. Additionally, an etch resist pattern may be used to form strength lines on the substrate surface.

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: Anode foils suitable for use in electrolytic capacitors, including those having multiple anode configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include disposing a resist material in a predetermined pattern on an exposed surface of an anode foil substrate such that a first portion of the exposed surface of the anode foil substrate is covered by the resist material, and a second portion of the exposed surface remains uncovered; polymerizing the resist material; exposing at least the second portion of the exposed surface to one or more etchants so as to form a plurality of tunnels; stripping the polymerized resist material; and widening at least a portion of the plurality of tunnels. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing.

Abstract: Anode foils suitable for use in electrolytic capacitors, including those having multiple anode configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include disposing a resist material in a predetermined pattern on an exposed surface of an anode foil substrate such that a first portion of the exposed surface of the anode foil substrate is covered by the resist material, and a second portion of the exposed surface remains uncovered; polymerizing the resist material; exposing at least the second portion of the exposed surface to one or more etchants so as to form a plurality of tunnels; stripping the polymerized resist material; and widening at least a portion of the plurality of tunnels. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing.

Abstract: A process for creating porous anode foil for use in an electrolytic capacitor of an implantable cardioverter defibrillator is provided. The process includes electrochemical drilling a plurality of etched metal foils in sequence one after the other in a bath containing electrochemical drilling (ECD) solution initially having a pH of less than 5. Alternatively, an etched foil sheet may be passed through the bath in a substantially continuous manner such that a portion of said etched foil sheet is in contact with the ECD solution is electrochemically drilled to generate pores. Electrochemical drilling is achieved when a current is passed to the foil or portion of the foil sheet in solution.

Abstract: Anode foils suitable for use in electrolytic capacitors, including those having multiple anode configurations, have improved strength, reduced brittleness, and increased capacitance compared to conventional anode foils for electrolytic capacitors. Exemplary methods of manufacturing an anode foil suitable for use in an electrolytic capacitor include disposing a resist material in a predetermined pattern on an exposed surface of an anode foil substrate such that a first portion of the exposed surface of the anode foil substrate is covered by the resist material, and a second portion of the exposed surface remains uncovered; polymerizing the resist material; exposing at least the second portion of the exposed surface to one or more etchants so as to form a plurality of tunnels; stripping the polymerized resist material; and widening at least a portion of the plurality of tunnels. The resist material may be deposited, for example, by ink-jet printing, stamping or screen printing.

Abstract: A method of producing electrodes for electrolytic capacitors by etching metal foil in a low pH etching electrolyte is disclosed. The low pH electrolyte is an aqueous solution, which comprises hydrochloric acid, glycerol, sodium perchlorate or perchloric acid, sodium persulfate and titanium (111) chloride. Anode foils etched according to the method of the invention maintain high capacitance gains, electrical porosity and strength. The electrical porosity of the etched foils is sufficiently high such that the overall Equivalent Series Resistance (ESR) is not increased in multilayer anodes configurations. Also described is a low pH electrolyte bath composition. Anode foils etched according to the present invention and electrolytic capacitors incorporating the etched anode foils are also disclosed.

Abstract: The present invention is directed to a method of creating porous anode foil for use in multiple anode stack configuration electrolytic capacitors, producing a pore structure that is microscopic in pore diameter and spacing, allowing for increased energy density with a minimal increase in ESR. Initially, an anode metal foil is etched, according to a conventional etch process, to produce an enlargement of surface area. The etched foil is then placed into the electrochemical drilling solution of the present invention. Alternatively, the etched foil may be masked, so that only small areas of the etched foil are exposed, prior to being placed in the electrochemical drilling solution. A DC power supply is used to electrochemically etch the masked or unmasked foil in the electrochemical drilling solution of the present invention such that pores on the order of a few microns diameter are produced through the foil.

Abstract: The present invention is directed to a method of etching anode foil in a non-uniform manner which increases the overall capacitance gain of the foil while retaining foil strength. In particular, by using a mask to protect a mesh grid of the foil from further etching, a previously etched foil can be further etched, prior to the widening step. Alternatively, the mask may be used in the initial etch, eliminating the need for the second process. In effect the foil may be etched to a higher degree in select regions, leaving a web of more lightly etched foil defined by the mask to retain strength. According to the present invention, the foil is placed between two masks with a grid of openings which expose the foil in these areas to the etching solution. The exposed area can be as little as 10% of the total foil to as much as 95% of the total foil, preferably 30% to 70% of the total foil area.

Abstract: A surface active, viscosity modifying agent is used to promote additional tunnel initiation during the etching of high purity cubicity anode foil, preferably aluminum anode foil, to render it suitable for use in electrolytic capacitors. The anode foil is etched in the electrolyte bath composition by passing a charge rough the bath, resulting in an anode foil having a higher capacitance than foils etched using known methods or etching compositions. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: An oxide dissolving acid dip is integrated into an anodic foil formation process. After a foil, either etched or un-etched, is hydrated in a bath of deionized water at an elevated temperature, the foil is then dipped in an organic acid mixture. Next, an oxide layer formation step is utilized to form a barrier oxide layer on a surface of the foil. Next, an oxide dissolving acid dip is utilized to selectively remove a diffuse hydrate layer formed in the formation process. The diffuse hydrate layer is responsible for the reduction of capacitance of the anodic foil. By the use of this oxide dissolving acid dip in conjunction with an organic acid dip, the foil exhibits reduced leakage current properties, while maintaining its capacitance. The treated foil can then be incorporated into a high voltage electrolytic capacitor suitable for use in an implantable cardioverter defibrillator.