Method for producing a high capacitance cathode by annealing a metallic foil in a nitrogen environment
US7955939B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 6, 2006 |
| Grant date | Jun 7, 2011 |
| Priority date | — |
| Expiry date | Jan 18, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01G9/0425
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention is a method for the production of a high capacitance foil for use as a cathode in an electrolytic capacitor by forming a nitride layer on at least one surface of the foil by annealing the foil at an elevated temperature in the presence of nitrogen gas (N2). By this method, an enhanced foil surface area can be achieved. Since the double layer capacitance of a cathode is proportional to the effective surface area of the cathode, the annealing process increases the cathode capacitance such that it can be effectively used in a high-gain multiple stacked anode electrolytic capacitor. After production of the foil by said method, the foil is cut into a shape that is suitable for assembly in such an electrolytic capacitor, which is commonly used in an implantable cardiac defibrillator (ICD).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.