# US 10,770,238 B2 · Solid electrolytic capacitor assembly with hydrophobic coatings > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,770,238 B2 - Document ID: US10770238B2 - Status: Granted - Kind: B2 - Application number: 16/026,260 - Filed: 2018-07-03 - Published: 2019-01-03 - Granted: 2020-09-08 - Earliest claimed: 2017-07-03 - Assignees: AVX Corporation - Applicants: AVX Corporation - Inventors: Lotfi Djebara; Martin Biler; Frantisek Priban - Web page: https://patentgrep.com/patent/US10770238B2 ## CPC - H01G 9/10: Sealing, e.g. of lead-in wires - H01G 9/0029: {Processes of manufacture} - H01G 9/012: specially adapted for solid capacitors - H01G 9/15: Solid electrolytic capacitors (H01G11/00 takes precedence) - H01G 9/028: Organic semiconducting electrolytes, e.g. TCNQ - H01G 9/052: Sintered electrodes - H01G 9/07: Dielectric layers - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) ## Abstract A capacitor assembly that comprises a solid electrolytic capacitor element is provided. The capacitor assembly also comprises a casing material that encapsulates the capacitor element, an anode termination that is in electrical connection with the anode body and contains a portion that is positioned external to the casing material, and a cathode termination that is in electrical connection with the solid electrolyte and contains a portion that is positioned external to the casing material. A first hydrophobic coating is disposed in contact with the casing material and the external portion of the anode termination and a second hydrophobic coating is disposed in contact with the casing material and the external portion of the cathode termination. ## Claims ### Claim 1 A capacitor assembly comprising: 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; a casing material that encapsulates the capacitor element, wherein the casing material has an outer surface that forms an outermost surface of the capacitor element; an anode termination that is in electrical connection with the anode body and contains a portion that is positioned external to the casing material, wherein a first hydrophobic coating is disposed in contact with the outer surface of the casing material and the external portion of the anode termination; and a cathode termination that is in electrical connection with the solid electrolyte and contains a portion that is positioned external to the casing material, wherein a second hydrophobic coating is disposed in contact with the outer surface of the casing material and the external portion of the cathode termination, wherein the first hydrophobic coating is separate from the second hydrophobic coating. ### Claim 2 (depends on 1) The capacitor assembly of claim 1, wherein the first hydrophobic coating, the second hydrophobic coating, or both have a thickness of from about 50 nanometers to about 2 micrometers. ### Claim 3 (depends on 1) The capacitor assembly of claim 1, wherein the first hydrophobic coating, the second hydrophobic coating, or both have a dielectric constant of about 10 or less as determined at a frequency of 1 kHz and 30% relative humidity. ### Claim 4 (depends on 1) The capacitor assembly of claim 1, wherein the first hydrophobic coating, the second hydrophobic coating, or both contain a fluoropolymer. ### Claim 5 (depends on 4) The capacitor assembly of claim 4, wherein the fluoropolymer is formed from a fluoroalkyl-substituted ethylenically unsaturated monomer. ### Claim 6 (depends on 4) The capacitor assembly of claim 4, wherein the fluoropolymer is formed from a fluoroalkyl (meth)acrylate. ### Claim 7 (depends on 1) The capacitor assembly of claim 1, wherein the first hydrophobic coating, the second hydrophobic coating, or both contain a polyvinylacetate. ### Claim 8 (depends on 1) The capacitor assembly of claim 1, wherein the casing material defines a top surface and opposing bottom surface, a rear surface and opposing front surface, and two opposing side surfaces. ### Claim 9 (depends on 8) The capacitor assembly of claim 8, wherein the exposed portion of the cathode termination that is in contact with the second hydrophobic coating is positioned generally parallel with the rear surface. ### Claim 10 (depends on 1) The capacitor assembly of claim 1, wherein the first hydrophobic coating is disposed in contact with the front surface and the second hydrophobic coating is disposed in contact with the rear surface. ### Claim 11 (depends on 10) The capacitor assembly of claim 10, wherein the exposed portion of the anode termination that is in contact with the first hydrophobic coating is positioned generally parallel with the front surface. ### Claim 12 (depends on 1) The capacitor assembly of claim 1, wherein the capacitor element further comprises a cathode coating that contains a metal particle layer that overlies the solid electrolyte, wherein the metal particle layer includes a plurality of conductive metal particles dispersed within a resinous polymer matrix. ### Claim 13 (depends on 1) The capacitor assembly of claim 1, wherein the anode body includes tantalum and the dielectric includes tantalum pentoxide. ### Claim 14 (depends on 1) The capacitor assembly of claim 1, wherein the solid electrolyte includes a plurality of conductive polymer particles. ### Claim 15 (depends on 14) The capacitor assembly of claim 14, wherein the conductive polymer particles contain an extrinsically conductive polymer having repeating units of the following formula (III): wherein, R7 is a linear or branched, C1 to C18 alkyl radical, C5 to C12 cycloalkyl radical, C6 to C14 aryl radical, C7 to C18 aralkyl radical, or a combination thereof; and q is an integer from 0 to 8. ### Claim 16 (depends on 14) The capacitor assembly of claim 14, wherein the extrinsically conductive polymer is poly(3,4-ethylenedioxythiophene). ### Claim 17 (depends on 14) The capacitor assembly of claim 14, wherein the particles also contain a polymeric counterion. ### Claim 18 (depends on 1) The capacitor assembly of claim 1, further comprising an external polymer coating that overlies the solid electrolyte and contains pre-polymerized conductive polymer particles. ### Claim 19 A method for sealing a capacitor assembly that contains 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; a casing material that encapsulates the capacitor element wherein the casing material has an outer surface that forms an outermost surface of the capacitor element; an anode termination that is in electrical connection with the anode body and contains a portion that is positioned external to the casing material; and a cathode termination that is in electrical connection with the solid electrolyte and contains a portion that is positioned external to the casing material, the method comprising: disposing a first hydrophobic coating formulation in contact with the external portion of the anode termination and the outer surface of the casing materiel and a second hydrophobic coating formulation in contact with the external portion of the cathode termination and the outer surface of the casing material; and folding the external portion of the anode termination so that the first coating formulation is sandwiched between a surface of the casing material and the external portion of the anode termination; and folding the external portion of the cathode termination so that the second coating formulation is sandwiched between a surface of the casing material and the external portion of the cathode termination, wherein the first hydrophobic coating is separate from the second hydrophobic coating. ### Claim 20 (depends on 19) The method of claim 19, wherein the first coating formulation, the second coating formulation, or both contain a fluoropolymer and a solvent. ### Claim 21 (depends on 20) The method of claim 20, wherein the solvent includes a hydrofluoroether. ### Claim 22 (depends on 19) The method of claim 19, wherein the first coating formulation, the second coating formulation, or both contain a polyvinylacetate and a solvent. ### Claim 23 (depends on 20) The method of claim 20, wherein the solvent includes an ester. ### Claim 24 (depends on 19) The method of claim 19, further comprising drying or curing the first and second coating formulations to form first and second coatings, respectively.