Battery separators with reduced splitting propensity
US6602593B1 · kind B1 · utility
63Cited by
10References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1999 |
| Grant date | Aug 5, 2003 |
| Priority date | — |
| Expiry date | Aug 30, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249981
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A split resistant microporous membrane is provided for use in preparing a battery separator. The microporous membrane has a TD tensile strength to MD tensile strength ratio of from about 0.12 to about 1.2, preferably from about 0.5 to about 1. The microporous membrane is made by a process which includes the steps of preparing a film precursor by blown film extrusion at a blow-up ratio of at least 1.5, annealing the film precursor, and stretching the resultant annealed film precursor to form the microporous membrane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.