MICROPOROUS MEMBRANE, LITHIUM ION SECONDARY BATTERY, AND MICROPOROUS MEMBRANE PRODUCTION METHOD

Title:

MICROPOROUS MEMBRANE, LITHIUM ION SECONDARY BATTERY, AND MICROPOROUS MEMBRANE PRODUCTION METHOD

Document Type and Number:

WIPO Patent Application WO/2018/043331

Kind Code:

A1

Abstract:

The present invention addresses the problem of minimizing the rate of film thickness change and the rate of air permeability resistance change after compression at 60℃ or 80℃. For stretching performed before solvent extraction, the present invention employs a method that involves stretching at least twice in at least two different axial directions, the stretching being performed to satisfy (i) and/or (ii). (i) Step (c) is a primary stretching step in which a sheet-shaped molded object is stretched at least once in each of a sheet transport direction (an MD direction) and a sheet width direction (a TD direction), and, in step (c), an MD stretching ratio and a TD stretching ratio satisfy (TD stretching ratio≥MD stretching ratio−2). (ii) The stretching temperature (T1) for first axis stretching that is performed first in step (c) and the maximum stretching temperature (T2) for second axis stretching that is performed second or later satisfy (T1−T2≥0).

Inventors:

ISHIHARA TAKESHI (JP)

Application Number:

PCT/JP2017/030538

Publication Date:

March 08, 2018

Filing Date:

August 25, 2017

Export Citation:

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Assignee:

TORAY INDUSTRIES (JP)

International Classes:

C08J9/26; C08J9/00; H01M50/417; H01M50/489; H01M50/491

Domestic Patent References:

WO2008035674A1	2008-03-27
WO2016132808A1	2016-08-25
WO2008093572A1	2008-08-07
WO2006106783A1	2006-10-12
WO2008016174A1	2008-02-07
WO2007052663A1	2007-05-10

Foreign References:

JP2015136809A	2015-07-30
JP2010024463A	2010-02-04
JP2014217800A	2014-11-20
JP2012038655A	2012-02-23
JP2007262203A	2007-10-11
JP2010540692A	2010-12-24
JP2012161936A	2012-08-30
JP3347835B2	2002-11-20

Other References: