Abstract:
A capacitor assembly for use in high voltage and high temperature environments is provided. More particularly, the capacitor assembly includes a capacitor element containing an anodically oxidized porous, sintered body that is coated with a manganese oxide solid electrolyte. To help facilitate the use of the capacitor assembly in high voltage (e.g., above about 35 volts) and high temperature (e.g., above about 175° C.) applications, the capacitor element is enclosed and hermetically sealed within a housing in the presence of a gaseous atmosphere that contains an inert gas. It is believed that the housing and inert gas atmosphere are capable of limiting the amount of moisture supplied to the manganese dioxide. In this manner, the solid electrolyte is less likely to undergo an adverse reaction under extreme conditions, thus increasing the thermal stability of the capacitor assembly. In addition to functioning well in both high voltage and high temperature environments, the capacitor assembly of the present invention may also exhibit a high volumetric efficiency.
Abstract:
A capacitor assembly configured to effectively dissipate heat when exposed to a high ripple current is provided. The assembly includes a plurality of capacitor elements, each including an anode body and lead, a dielectric layer overlying the anode body, and a solid electrolyte. Each capacitor element is defined by upper and lower major surfaces, first opposing minor surfaces, and second opposing minor surfaces. The major surfaces each have a surface area greater than that of each of the minor opposing surfaces. A hermetically sealed housing having a length, width, and height defines an interior cavity within which the plurality of capacitor elements are positioned. The ratio of the length to the height ranges from about 2 to about 80. Further, the lower major face of each capacitor element faces a lower wall of the housing, where the lower wall is defined by the housing's length and width.
Abstract:
A solid electrolytic capacitor that comprises a sintered porous anode, a dielectric layer that overlies the anode body, and a solid electrolyte overlying the dielectric layer is provided. The solid electrolyte comprises a conductive polymer and a nonionic surfactant having a hydrophilic/lipophilic balance (“HLB”) of from about 10 to about 20 and a molecular weight of from about 100 to about 10,000 grams per mole. The nonionic surfactant has a hydrophobic base and a hydrophilic chain that contains alkoxy moieties.
Abstract:
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).
Abstract:
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.
Abstract:
A solid electrolytic capacitor containing a capacitor element is provided. The capacitor element contains a sintered porous anode body, a dielectric that overlies the anode body, a pre-coat that overlies the dielectric, and a solid electrolyte that overlies the pre-coat. The solid electrolyte includes a conductive polymer having repeating units derived from an aniline monomer having the following general formula (I):
Abstract:
A wet electrolytic capacitor containing a cathode, fluidic working electrolyte, and planar anode formed from an anodically oxidized sintered porous pellet is provided. The pellet may be formed from a pressed valve metal powder, which in turn, is formed by reacting an oxide of a valve metal compound (e.g., tantalum pentoxide) with a reducing agent that contains a metal having an oxidation state of 2 or more (e.g., magnesium). Through the use of such a powder, the present inventors have discovered that higher capacitance levels can be achieved than previously thought possible for the high voltage capacitors employed in implantable medical devices.
Abstract:
A solid electrolytic capacitor containing a capacitor element is provided. The capacitor element contains a sintered porous anode body, a dielectric that overlies the anode body, a solid electrolyte that overlies the dielectric, wherein the solid electrolyte includes a conductive polymer layer, and a moisture barrier that overlies the conductive polymer layer.
Abstract:
A wet electrolytic capacitor that contains a cathode, fluidic working electrolyte, and anode that includes a sintered porous pellet is provided. A dielectric layer is also formed on a surface of the pellet and within its pores through anodic oxidation. The present inventors have discovered that through selective control over the anodic oxidation process, a substantially amorphous, low crystalline dielectric layer can be formed which, among other things, exhibits a leakage current that is smaller than previously thought possible for the high voltage capacitors employed in implantable medical devices.
Abstract:
A capacitor assembly that is capable of performing well under the conditions of high humidity (e.g., 60% relative humidity) is provided. The capacitor assembly comprises a solid electrolytic capacitor element that contains a sintered porous anode body, a dielectric that overlies the anode body, and a solid electrolyte that overlies the dielectric. An anode termination is in electrical connection with the anode body and a cathode termination is in electrical connection with the solid electrolyte. A first coating is disposed on at least a portion of the anode termination that contains an organometallic compound and a second coating is disposed on at least a portion of the cathode termination that contains an organometallic compound. Further, a casing material encapsulates the capacitor element and leaves exposed a mounting surface of the anode termination and the cathode termination.