Patent · US Active

Polyolefin microporous membrane base for nonaqueous secondary battery separator, method for producing the same, nonaqueous secondary battery separator and nonaqueous secondary battery

US7892672B2 · kind B2 · utility

41Cited by
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12Claims
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Key dates

Filing dateJun 4, 2008
Grant dateFeb 22, 2011
Priority date
Expiry dateJun 4, 2028

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/10
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A nonaqueous secondary battery separator is provided that is excellent in heat resistance, shutdown characteristics, membrane resistance and handling property. The present invention is a polyolefin microporous membrane used for a nonaqueous secondary battery separator containing the polyolefin microporous membrane at least one surface of which is coated and integrated with a heat resistant porous layer, characterized in that the membrane has (A) a thickness of 5 to 20 μm, (B) a porosity of 35 to 50%, (C) an air permeability per unit thickness (JIS P8117) of 10 to 30 sec/100 cc·μm and a total air permeability of the membrane (JIS P8117) of 400 sec/100 cc or less, and (D) Y/X of 1×10−3 to 1×10−2 ohm·cm2/(sec/100 cc), wherein the air permeability (JIS P8117) is represented by X sec/100 cc, and the membrane resistance upon impregnating the polyolefin microporous membrane with an electrolytic solution is represented by Y ohm·cm2.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.