Avx Corporation

Kyocera Avx Components Corporation

Ladislav Vilc

Martin Biler

Stanislav Zednicek

Ivan Horacek

Jan Petrzilek

Lotfi Djebara

Silvie Vilcova

Irena Pfitznerova

Marek Stabl

A capacitor that comprises a solid electrolytic capacitor element, a casing material that encapsulates the capacitor element, an anode termination, and a cathode termination is provided. A nanocoating is disposed on at least a portion of the capacitor element, casing material, anode termination, cathode termination, or a combination thereof. The nanocoating has an average thickness of about 2,000 nanometers or less and contains a vapor-deposited polymer.

Solid electrolytic capacitor containing a nanocoating

A capacitor assembly that is capable of performing well under the conditions of high humidity and temperature (e.g., 85% relative humidity/85&#xb0; C.) is provided. The capacitor assembly comprises a solid electrolytic capacitor element, an anode termination that is in electrical connection with the anode body, cathode termination that is in electrical connection with the solid electrolyte, and casing material that encapsulates the capacitor element and leaves exposed at least a portion of the anode termination and the cathode termination. The casing material is formed from an epoxy composition that contains one or more inorganic oxide fillers and a resinous material that includes one or more epoxy resins crosslinked with a co-reactant, wherein inorganic oxide fillers about 75 wt. % or more of the epoxy composition, and vitreous silica constitutes about 30 wt. % or more of the total weight of inorganic oxide fillers in the epoxy composition.

Casing material for a solid electrolytic capacitor

A solid electrolytic capacitor that comprises a capacitor element, a lead wire, an anode termination, and a cathode termination is provided. The capacitor element contains a sintered porous anode body, a dielectric that overlies the anode body, and a solid electrolyte that overlies the dielectric. Further, the lead wire is in electrical contact with the anode body and contains a first region that is located in proximity to a surface of the capacitor element. The lead wire contains a core that extends outwardly from the surface, and an oxide layer coats at least a portion of the core within the first region.

Lead wire configuration for a solid electrolytic capacitor

A capacitor that is capable of exhibiting good properties under humid conditions is provided. The ability to perform under such conditions is due in part to selective control over the particular nature of the solid electrolyte and cathode coating that overlies the solid electrolyte. For example, the solid electrolyte contains pre-polymerized conductive polymer particles, which can help act as a blocking layer for any silver ions migrating through the capacitor. Likewise, the cathode coating also contains conductive metal particles (e.g., silver particles) that are dispersed within a resinous matrix. The resinous matrix includes a polymer that absorbs only a small amount of water, if any, when placed in a humid atmosphere.

Solid electrolytic capacitor for use in a humid atmosphere

A solid electrolytic capacitor that includes an anode body, dielectric overlying the anode body, and solid electrolyte that overlies the dielectric is provided. The solid electrolyte includes a nanocomposite that contains a plurality of nanofibrils dispersed within a conductive polymer matrix. The nanofibrils have a relatively small size and high aspect ratio, which the present inventors have discovered can dramatically improve the thermal-mechanical stability and robustness of the resulting capacitor.

Stable solid electrolytic capacitor containing a nanocomposite

A capacitor assembly that contains a solid electrolytic capacitor element positioned within a multi-layered casing is provided. The casing contains an encapsulant layer that overlies the capacitor element and a moisture barrier layer that overlies the encapsulant layer. Through careful control of the materials employed in the casing, the present inventor has discovered that the resulting capacitor assembly can be mechanically stable while also exhibiting electrical properties in the presence of high humidity levels (e.g., relative humidity of 85%). For example, the encapsulant layer may be formed from a thermoset resin (e.g., epoxy) that is capable of providing the capacitor element with mechanical stability. The moisture barrier layer may likewise be formed from a hydrophobic material.

Moisture resistant solid electrolytic capacitor assembly

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., Feor Feions) that can lead to dielectric degradation, particularly at relatively high voltages (e.g., above about 60 volts). Furthermore, to help protect the stability of the solid electrolyte at high temperatures, the capacitor element is enclosed and hermetically sealed within a housing in the presence of a gaseous atmosphere that contains an inert gas.

Solid electrolytic capacitor for use in high voltage and high temperature applications

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.

Hermetically sealed capacitor assembly

A solid electrolytic capacitor element that is capable of withstanding laser welding without a significant deterioration in its electrical performance is provided. The capacitor element contains an anode body, dielectric, and solid electrolyte. To help shield the solid electrolyte from damage that might otherwise occur during manufacture of the capacitor, a multi-layered protective coating is employed in the present invention that overlies at least a portion of the solid electrolyte. More particularly, the protective coating includes a light reflective layer overlying the solid electrolyte and a stress dissipation layer overlying the light reflective layer. The light reflective layer can help reflect any light that inadvertently travels toward the capacitor during, for example, laser welding. This results in reduced contact of the solid electrolyte with the laser and thus minimizes defects in the electrolyte that would have otherwise been formed by carbonization. The stress dissipation layer can likewise help to dissipate stresses experienced by the capacitor (e.g., during encapsulation, reflow, etc.) so that they are not as likely to cause damage to the solid electrolyte. The stress dissipation layer can also be relatively porous in nature so that humidity trapped in the capacitor can escape and diminish the pressure that might otherwise be transferred to the solid electrolyte.

Solid electrolytic capacitor element

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.

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Lanskroun, Czechia

Ladislav Vilc