Wet-laid nonwoven fabric for battery separator, its production method and sealed type secondary battery
US5888916A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1997 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Jun 27, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/69
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An improved wet-laid nonwoven fabric for a battery separator wherein 20 to 95% by weight of thermoplastic staple fibers having a single fiber diameter of 20 .mu.rm, or less are three-dimensionally entangled with hot-melt fibers having a melting point lower by 20.degree. C. than that of the thermoplastic staple fibers so that a mean fiber entangling point interval is 300 .mu.m or less, wherein at least part of the hot-melt fibers are fused to bond the fibers with each other to fix the nonwoven structure. The nonwoven fabric has a basis weight in a range from 10 to 350 g/m.sup.2, a thickness in a range from 30 to 1000 .mu.m and an apparent density in a range from 0.26 to 0.7 g/cm.sup.3, and is excellent in uniformity and mechanical strength. The wet-laid nonwoven fabric is particularly excellent in air permeability, liquid holding capability, liquid retention capability and liquid absorption rate and satisfies the requirement for a battery separator. Therefore, it is useful for the production of a high performance secondary battery having favorable overcharging characteristics and cycle characteristics. The wet-laid nonwoven fabric according to the present invention is prepared by su…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.