Porous Membrane and Multilayer Porous Membrane

Patent metadata

Field	Value
Publication number	US-2017194613-A1
Application number	US-201715462794-A
Country	US
Kind code	A1
Filing date	Mar 17, 2017
Priority date	Mar 28, 2012
Publication date	Jul 6, 2017
Grant date	—

Abstract

A multilayer porous membrane comprising: a porous membrane containing a polyolefin resin as a main component; and a porous layer containing an inorganic filler and a resin binder and laminated on at least one surface of the porous membrane;
wherein the porous membrane has an average pore size d=0.035 to 0.060 μm, a tortuosity τ a =1.1 to 1.7, and the number B of pores=100 to 500 pores/μm 2 , which are calculated by a gas-liquid method, and the porous membrane has a membrane thickness L=5 to 22 μm.

First claim

1 - 11 . (canceled)

12 . A separator for nonaqueous electrolyte batteries comprising:
a porous membrane (A) comprising a polyolefin resin as a main component; and a porous layer (B) comprising an inorganic filler and a resin binder, where the porous layer is laminated on at least one surface of the porous membrane (A); wherein the porous membrane (A) has a porosity of not less than 50% and not more than 90%, and a number of pores of not less than 100 pores/μm 2 and not more than 500 pores/μm 2 , and wherein the resin binder present in the porous layer (B) is a resin latex binder having an average particle size of not less than 50 nm and not more than 500 nm.

13 . (canceled)

14 . A nonaqueous electrolyte battery, comprising:
the separator for nonaqueous electrolyte batteries according to claim 12 , a positive electrode, a negative electrode, and an electrolytic solution.

15 . The separator for nonaqueous electrolyte batteries according to claim 12 , wherein the polyolefin composition comprises polypropylene and a polyolefin other than the polypropylene.

16 . The separator for nonaqueous electrolyte batteries according to claim 12 , wherein a proportion of polypropylene based on total polyolefin present in the resin is 1 to 35% by mass.

17 . The separator for nonaqueous electrolyte batteries according to claim 12 , wherein a viscosity average molecular weight of the polyolefin resin is not less than 50,000 and less than 2,000,000.

Assignees

• Asahi Kasei E Materials Corp

Inventors

• Murata Hiroshi
• Hatayama Hiroshi
• Uchida Yuki
• Ishikawa Masaki

Classifications

• B32B27/32 Primary

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• B32B2457/10

  Batteries · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• B32B2307/724

  Permeability to gases, adsorption · CPC title