Porous membrane and process for preparing the same
US8765308B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 2012 |
| Grant date | Jul 1, 2014 |
| Priority date | — |
| Expiry date | Oct 12, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/70
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a porous membrane containing cellulose fibers, wherein the cellulose fibers contain 5% by weight or more of cellulose fibers with a diameter of 1 μm or more, relative to the total weight of the cellulose fibers, the mode diameter (maximal frequency) of the pore distribution determined by the mercury penetration method is less than 0.3 μm, the air resistance per thickness of 10 μm is from 20 to 600 seconds, and the porous membrane has a volume resistivity of 1500 Ω·cm or less determined by alternate current with a frequency of 20 kHz in which the porous membrane is impregnated with 1 mol/LiPF6/propylene carbonate solution. The porous membrane according to the present invention can provide a separator for electrochemical devices with superior properties at a reasonable cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.