Aluminum electrode plate for electrolytic capacitor
US7903391B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2007 |
| Grant date | Mar 8, 2011 |
| Priority date | — |
| Expiry date | Jul 11, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01G9/055
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
This invention provides an aluminum electrode plate for an electrolytic capacitor, which, even when the thickness of an etching layer is large, can realize a high level of impregnation of a solid electrolyte and can reduce ESR of a capacitor. An aluminum plate having an aluminum purity of not less than 99.98% by mass is etched to form an etching layer having a depth of 70 μm or above. When a plane cross section of a position deeper than 20 μm from the surface in the etching layer is measured with an image analyzer, for each measured face, not less than 70% of the total number of pits within the measured face is accounted for by pits having a diameter of 0.01 to 1 μm φ; in terms of equivalent circle diameter. The aluminum plate has an aluminum purity of not less than 99.98% by mass and comprises 5 to 50 ppm of Fe and 5 to 40 ppm of Cu with the balance consisting of inevitable impurities. The aluminum plate further contains 1×107 to 1010/cm3 iron-containing intermetallic compound having a particle diameter of 0.1 to 1.0 μm φ in terms of spheres.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.