Nonaqueous electrolyte secondary cells
US6899973B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2003 |
| Grant date | May 31, 2005 |
| Priority date | — |
| Expiry date | Dec 22, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49114
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A nonaqueous electrolyte secondary cell comprises a rolled-up electrode unit 2 composed of a positive electrode 23, a negative electrode 21 and a separator 22 interposed therebetween, and a negative electrode current collector plate 3 and a positive electrode current collector plate 30 joined to the respective ends of the electrode unit 2. The negative electrode collector plate 3 is joined to an edge of the negative electrode 21 projecting at one of the opposite ends of the electrode unit 2. The collector plate 3 has a two-layer structure comprising a copper layer 31 made of copper or an alloy consisting predominantly of copper, and a metal layer made of a metal not forming an intermetallic compound with lithium and having a lower laser beam reflectivity than copper or an alloy consisting predominantly of the metal. The collector plate 3 has its copper layer 31 contacted with the edge of the negative electrode 21 and welded thereto with a laser beam. This improves the weldability of the collector plate 3 to the rolled-up electrode unit 2 to achieve a high current collecting efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.