Patent application number | Description | Published |
20080232033 | SOLID ELECTROLYTIC CAPACITOR CONTAINING A BARRIER LAYER - An electrolytic capacitor containing an anode and solid electrolyte overlying the anode is provided. The capacitor may also include a barrier layer that overlies the solid electrolyte to help protect the capacitor from its working environment. More specifically, the barrier layer may include a three-dimensional crosslinked network that provides excellent adhesion to the underlying layers, and also improved barrier properties to moisture. In this manner, the barrier layer can enable the electrolytic capacitor to increase it performance in relatively high humidity and/or high temperature environments. | 09-25-2008 |
20080232035 | SOLID ELECTROLYTIC CAPACITOR CONTAINING A PROTECTIVE ADHESIVE LAYER - An electrolytic capacitor containing a protective adhesive layer positioned between the dielectric layer and the solid electrolyte layer (e.g., a conductive polymer layer, manganese dioxide) is generally disclosed. The protective adhesive layer can include a polymer having a repeating unit with a functional hydroxyl group, such as poly(vinyl alcohol). For instance, the polymer can be at least 90 mole % hydrolyzed. The polyvinyl alcohol can be a co-polymer of vinyl alcohol and a monomer, such as an acrylic ester like a methacrylic ester (e.g., methyl methacrylate). | 09-25-2008 |
20080232037 | SOLID ELECTROLYTIC CAPACITOR CONTAINING A CONDUCTIVE POLYMER - A method for forming an electrolytic capacitor is disclosed. The method includes forming a conductive polymer coating by polymerizing a monomer in the presence of less than a stoichiometric amount of an oxidative polymerization catalyst. The present inventor has found that the use of less than the stoichiometric amount of the oxidative polymerization catalyst per mole of monomer can slow the polymerization of the monomer, creating oligomers that are shorter in length than if fully polymerized into a polymer. Without wishing to be bound by theory, it is believed that these shorter oligomers provide better penetration into the porous anode. Thus, the resulting conductive polymer layer can be more intimately positioned with respect to the anode. As a result, the formed capacitor can exhibit better performance. | 09-25-2008 |
20080310080 | Solid State Capacitors and Method of Manufacturing Them - The present invention concerns the field of solid state capacitors and is directed more particularly to a method for manufacturing solid state electrolytic capacitors formed from porous conductive metal oxide anode bodies and having a cathode layer of conducting polymer, and capacitors thereby formed. There is disclosed a solid state capacitor comprising a porous anode body, a dielectric layer formed on surfaces of the porous anode body and a cathode layer formed on the dielectric layer, characterised by the combination of the anode body being formed from an electrically conducting ceramic material and the cathode layer being formed from an electrically conductive polymer material. The conducting ceramic material may be a metal oxide or nitride. | 12-18-2008 |
20090154058 | POLYMER BASED SOLID STATE CAPACITORS AND A METHOD OF MANUFACTURING THEM - The present invention relates to a solid state capacitor having a conductive polymer cathode layer counter electrode comprising acrylate binder and a method for its manufacture. In particular the present invention relates to a solid state capacitor comprising: providing a porous anode body of valve action material; forming a dielectric layer on said porous body; forming a cathode layer in contact with said dielectric layer, which cathode layer comprises a conductive polymer and an acrylic binder; and providing an anode terminal in electrical connection with the porous body anode and a cathode terminal in electrical connection with the cathode layer and a method for its manufacture. | 06-18-2009 |
20090166211 | Solid Electrolytic Capacitor Containing a Conductive Polymer - A method for forming an electrolytic capacitor is disclosed. The method includes forming a conductive polymer coating over the dielectric layer by polymerizing a monomer in the presence of an oxidative polymerization catalyst. The conductive polymer coating is formed by dipping the anode in a polymerization solution comprising the monomer, the oxidative polymerization catalyst, and a polar solvent. The polymerization solution has a temperature of less than about 20° C. Cooling the polymerization solution further stabilizes the polymerization solution and prevents premature polymerization of the monomer(s). Thus, the resulting conductive polymer layer can be more intimately positioned with respect to the anode. As a result, the formed capacitor can exhibit better performance. | 07-02-2009 |
20090185329 | Electrolytic Capacitor Anode Treated with an Organometallic Compound - An electrolytic capacitor that contains an anodically oxidized anode that is incorporated with an additional metallic element is provided. More specifically, the metallic element is built into the valve metal pentoxide of the dielectric layer. In one particular embodiment, the addition of the metallic element results in a niobium pentoxide dielectric that contains closely packed units of O atoms, Nb | 07-23-2009 |
20090185330 | Sintered Anode Pellet Etched with an Organic Acid for Use in an Electrolytic Capacitor - An electrolytic capacitor anode etched with an organic acid prior to anodic oxidation of the anode to create the dielectric layer. Without intending to be limited by theory, it is believed that the organic acid can etch away at least a portion of any oxides on the anode. This provides a relatively uniform surface for the creation of the dielectric, which in turn leads to a dielectric layer having a substantially uniform thickness and homogeneous amorphous structure and thus improved leakage current and stability. The organic acid may also have other residual benefits, such as removing any metallic impurities from the surface of the anode. | 07-23-2009 |
20090185941 | Sintered Anode Pellet Treated with a Surfactant for Use in an Electrolytic Capacitor - An electrolytic capacitor anode treated with a surfactant during anodic oxidation is provided. Without intending to be limited by theory, it is believed that the surfactant may lower the surface tension of an electrolyte, which inhibits the clustering of grown oxides and allows the dielectric layer to become more homogeneous and uniformly spread over the anode body. The resulting dielectric layer may thus have a substantially homogeneous thickness, smooth surface, and improved leakage current stability. | 07-23-2009 |
20100025876 | BINDER REMOVAL FROM PARTICULATE BODIES - The present invention relates to a method of manufacturing a porous article, in particular the anode of a valve action material based solid state capacitor, comprising the steps of combining a water soluble polymeric binder and particulate material before pressing the particulate material and the subsequent step of removing the binder form the pressed pellet. Thus, the present invention also relates to a method of removing a water soluble polymeric binder from pressed particulate material and to a composition comprising a water soluble polymeric binder for forming the anode of a valve action material based solid state capacitor. | 02-04-2010 |
20110085285 | Hermetically Sealed Capacitor Assembly - A capacitor assembly that includes an electrolytic capacitor that contains an anode body, dielectric overlying the anode, and a solid electrolyte overlying the dielectric is provided. An anode lead is also electrically connected to the anode body and extends in a longitudinal direction therefrom. The anode lead is connected to an “upstanding” portion of a leadframe. Among other things, this helps to limit substantial horizontal movement of the lead and thereby improve the mechanical robustness of the part. The capacitor and leadframe are enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas. It is believed 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 solid electrolyte (e.g., conductive polymer) is less likely to undergo a reaction in high temperature environments, thus increasing the thermal stability of the capacitor assembly. | 04-14-2011 |
20120069491 | Technique for Forming a Cathode of a Wet Electrolytic Capacitor - A technique for forming a cathode of a wet electrolytic capacitor is provided. The cathode contains a metal substrate having a roughened surface and a conductive coating that contains a substituted polythiophene. The degree of surface contact between the conductive coating and the roughened surface is enhanced in the present invention by selectively controlling the manner in which the conductive coating is formed. More particularly, the conductive coating is formed by applying a precursor solution to the roughened surface that includes both a precursor thiophene monomer and an oxidative catalyst. Contrary to techniques in which either the monomer or catalyst is applied separately and initially contacts the metal surface, the presence of the monomer and catalyst within the same solution allows polymer chains to grow immediately adjacent to the surface of the metal substrate and within the pits. This can significantly increase 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). To minimize the likelihood of premature polymerization, the oxidative catalyst is also employed in an amount less than what is required to fully react all of the reagent assuming 100% yield (i.e., “stoichiometric amount”). This can slow the polymerization of the monomer, creating oligomers that are shorter than if fully polymerized, which can better penetrate into the roughened regions of the metal substrate. | 03-22-2012 |
20120069492 | Abrasive Blasted Conductive Polymer Cathode for Use in a Wet Electrolytic Capacitor - 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). | 03-22-2012 |
20120106031 | Solid Electrolytic Capacitor for Use in High Voltage and High Temperature Applications - A capacitor assembly for use in high voltage and high temperature environments is provided. More particularly, the capacitor assembly includes a solid electrolytic capacitor element containing an anode body, a dielectric overlying the anode, and a solid electrolyte overlying the dielectric. To help facilitate the use of the capacitor assembly in high voltage applications, it is generally desired that the solid electrolyte is formed from a dispersion of preformed conductive polymer particles. In this manner, the electrolyte may remain generally free of high energy radicals (e.g., Fe | 05-03-2012 |
20120147528 | Conductive Coating for Use in Electrolytic Capacitors - A dispersion that contains an intrinsically conductive polythiophene formed via poly(ionic liquid)-mediated polymerization is provided. Without intending to be limited by theory, it is believed that a thiophene monomer can polymerize along the chains of a poly(ionic liquid). In this manner, the poly(ionic liquid) may act as a template for polymerization to provide a particle dispersion that is substantially homogeneous and stable. Such dispersions may be employed in an electrolytic capacitor as a solid electrolyte and/or as a conductive coating that is electrical communication with the electrolyte. Regardless, the dispersion may be more easily and cost effectively formed and incorporated into the structure of the capacitor. Moreover, due to the presence of the ionic liquid, the dispersion is conductive and does not require the addition of conventional dopants, such as polystyrene sulfonic acid. For example, the dispersion may have a specific conductivity, in the dry state, of about 1 Siemen per centimeter (“S/cm”) or more, in some embodiments about 10 S/cm or more, in some embodiments about 20 S/cm or more, and in some embodiments, from about 50 to about 500 S/cm. | 06-14-2012 |
20120147529 | Solid Electrolytic Capacitor Containing a Poly(3,4-Ethylenedioxythiophene) Quaternary Onium Salt - A solid electrolytic capacitor a solid electrolytic capacitor that includes an anode body, a dielectric overlying the anode body, and a solid electrolyte overlying the dielectric is provided. The capacitor also comprises a conductive polymer coating that overlies the solid electrolyte and includes nanoparticles formed from a poly(3,4-ethylenedioxythiophene) quaternary onium salt. | 06-14-2012 |
20120229955 | Solid Electrolytic Capacitor Containing a Conductive Coating Formed from a Colloidal Dispersion - A solid electrolytic capacitor that includes an anode body, a dielectric overlying the anode body, a solid electrolyte overlying the dielectric, and a colloidal particle coating that overlies the solid electrolyte. The coating is formed from a colloidal particle dispersion. The particles of the dispersion contain at least two different polymer components—i.e., a conductive polymer and a latex polymer. One benefit of such a coating is that the presence of the latex polymer can help mechanically stabilize the capacitor during encapsulation due to its relatively soft nature. This helps limit delamination of the solid electrolyte and any other damage that may otherwise occur during formation of the capacitor. Furthermore, the latex polymer can also enhance the ability of the particles to be dispersed in an aqueous medium, which is desirable in various applications. | 09-13-2012 |
20120257327 | HERMETICALLY SEALED ELECTROLYTIC CAPACITOR WITH ENHANCED MECHANICAL STABILITY - A capacitor assembly that is thermally and mechanically stable in high temperature environments is provided. Thermal stability is provided by enclosing and hermetically sealing the capacitor element within a housing in the presence of a gaseous atmosphere that contains an inert gas, thereby limiting the amount of oxygen and moisture supplied to the solid electrolyte of the capacitor. To provide the assembly with good mechanical stability, a polymeric restraint is also employed that is positioned adjacent to and in contact with one or more surfaces of the capacitor element. Without intending to be limited by theory, it is believed that the strength and rigidity of the polymeric restraint can help the capacitor element better withstand vibrational forces incurred during use without resulting in delamination. In this manner, the capacitor assembly is able to better function in high temperature environments. | 10-11-2012 |
20120257328 | Housing Configuration for a Solid Electrolytic Capacitor - A capacitor assembly that is stable under extreme conditions is provided. More particularly, the assembly includes a capacitor element that is positioned within an interior cavity of a housing. The housing includes a base to which the capacitor element is connected. The housing also includes a lid that contains an outer wall from which extends a sidewall. An end of the sidewall is defined by a lip extending at an angle relative to the longitudinal direction and having a peripheral edge located beyond a periphery of the sidewall. The lip is hermetically sealed to the base. In some cases, the peripheral edge of the lip is also coplanar with an edge of the base. The use of such a lip can enable a more stable connection between the components and improve the seal and mechanical stability of the capacitor assembly, thereby allowing it to better function under extreme conditions. | 10-11-2012 |
20120307420 | Hermetically Sealed Capacitor Assembly - A capacitor assembly that includes an electrolytic capacitor that contains an anode body, dielectric overlying the anode, and a solid electrolyte overlying the dielectric is provided. An anode lead is also electrically connected to the anode body and extends therefrom. The capacitor and leadframe are enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas. In this manner, the solid electrolyte (e.g., conductive polymer) is less likely to undergo a reaction in high temperature environments, thus increasing the thermal stability of the capacitor assembly. | 12-06-2012 |
20130155580 | Wet Electrolytic Capacitor Containing an Improved Anode - A wet electrolytic capacitor that includes a sintered porous anode body containing a dielectric layer, a fluid electrolyte, and a cathode is provided. At least one longitudinally extending channel is recessed into the anode body. The channel may have a relatively high aspect ratio (length divided by width), such as about 2 or more, in some embodiments about 5 or more, in some embodiments from about 10 to about 200, in some embodiments from about 15 to about 150, in some embodiments from about 20 to about 100, and in some embodiments, from about 30 to about 60. | 06-20-2013 |
20130242464 | Wet Capacitor Cathode Containing a Conductive Copolymer - A wet electrolytic capacitor that contains an anodically oxidized porous anode body, a cathode containing a metal substrate coated with a conductive coating, and a working electrolyte that wets the dielectric on the anode. The conductive coating contains a conductive copolymer having at least one thiophene repeating unit, as well as a pyrrole repeating unit and/or aniline repeating unit. | 09-19-2013 |
20130242465 | Wet Capacitor Cathode Containing a Conductive Coating Formed Anodic Electrochemical Polymerization of a Colloidal Suspension - A wet electrolytic capacitor that contains an anodically oxidized porous anode body, a cathode containing a metal substrate coated with a conductive coating, and a working electrolyte that wets the dielectric on the anode. The conductive coating is formed through anodic electrochemical polymerization (“electro-polymerization”) of a precursor colloidal suspension on the surface of the substrate. The colloidal suspension includes a precursor monomer, ionic surfactant, and sulfonic acid, which when employed in combination can synergistically improve the degree of surface coverage and overall conductivity of the coating. | 09-19-2013 |
20130242467 | Wet Capacitor Cathode Containing an Alkyl-Substituted Poly(3,4-Ethylenedioxythiophene) - A wet electrolytic capacitor that contains an anodically oxidized porous anode body, a cathode containing a metal substrate coated with a conductive coating, and a working electrolyte that wets the dielectric on the anode. The conductive coating contains an alkyl-substituted poly(3,4-ethylenedioxythiophene) having a certain structure. Such polymers can result in a higher degree of capacitance than many conventional types of coating materials. Further, because the polymers are generally semi-crystalline or amorphous, they can dissipate and/or absorb the heat associated with the high voltage. The degree of surface contact between the conductive coating and the surface of the metal substrate may also be enhanced in the present invention by selectively controlling the manner in which the conductive coating is formed. | 09-19-2013 |