Patent · US Expired

High surface area cathode for electrolytic capacitors using conductive polymer

US7169284B1 · kind B1 · utility

31Cited by
16References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 2003
Grant dateJan 30, 2007
Priority date
Expiry dateNov 30, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/13
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The present invention is directed to a conductive polyethylenedioxythiophene (PEDOT) polymer coated electrode adapted for use as a cathode electrode of an electrolytic capacitor and a method of manufacturing the same. According to the present invention, a metal foil substrate is placed in an aqueous solution of a doped 3,4-ethylenedioxythiophene (EDOT) monomer and a co-solvent, to dissolve the EDOT monomer, and a current is applied until the desired thickness of the polymer coating is electrochemically deposited. Additionally, an organic acid is added to the aqueous solution to act as an oxidizer. In order to improve the uniformity and adherence of the coating a surfactant may also be added. In a preferred embodiment, the EDOT monomer and cosolvent are first mixed, and then added to a water solution of oxidizer and dopant. The polymer film is deposited electrochemically onto the substrate by applying a DC current between 0.05 mA/cm2 and 5.0 mA/cm2 for 1 to 60 minutes, more preferably between about 0.13 mA/cm2 to about 0.26 mA/cm2 for between 9 and 18 minutes, such that a conductive polyethylenedioxythiophene (PEDOT) coating is formed on the electrode surface. According to the prese…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.