Leak proof pressure relief valve for secondary batteries
US6949310B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 15, 2002 |
| Grant date | Sep 27, 2005 |
| Priority date | — |
| Expiry date | Apr 29, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Secondary batteries are subjected to power cycling, and those which have a liquid electrolyte within the interior volume are equipped with a pressure relief valve. A void space over the liquid electrolyte may be subjected to gas pressure variations with respect to the ambient. The pressure relief valve structure comprises a vertically oriented gas flow chamber, and an outer relief vent adapted to open only when gas pressure within the battery and the gas flow chamber exceeds a predetermined pressure with respect to the ambient pressure. The gas flow chamber extends below the top surface of the battery, and has a dome-like cap which extends downwardly and has a plurality of openings so as to permit unimpeded gas flow between the interior of the battery and the gas flow chamber. There is a porous membrane covering the dome which permits gas flow between the interior of the battery and the gas flow chamber, but precludes flow of liquid electrolyte from the interior volume of the battery to the gas flow chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.