Embossed microporous membrane battery separator materials and methods of manufacture and use thereof

Abstract

Disclosed are embossed microporous membranes, as well as articles (e.g., battery separators, materials, textiles, composites, and laminates) comprising the embossed microporous membranes. Also provided are methods of making and/or using embossed microporous membranes.

1 .- 33 . (canceled) 
     
     
         34 . An embossed microporous membrane prepared by a process comprising embossing, calendering or compressing a microporous polymer film comprising a plurality of pores having a substantially round shape. 
     
     
         35 . The membrane of  claim 34 , wherein the microporous polymer film exhibits a ratio of machine direction (MD) tensile strength to transverse direction (TD) tensile strength of from 0.5 to 5.0. 
     
     
         36 . The membrane of  claim 34 , wherein the polymer film is made by a dry-stretch process. 
     
     
         37 . The membrane of  claim 34 , wherein the embossed microporous membrane exhibits increased MD tensile strength, increased TD tensile strength, increased puncture strength, decreased MD splitting, or a combination thereof as compared to the microporous polymer film. 
     
     
         38 . The membrane of  claim 34 , wherein the embossed microporous membrane comprises an embossing pattern selected from the group consisting of embossed horizontal lines running parallel to the TD of the membrane, an embossed crosshatch-type pattern at an angle relative to the MD and TD of the membrane, embossed circles in a pseudorandom pattern, a pseudorandom object pattern, a logo pattern, and combinations thereof. 
     
     
         39 . The membrane of  claim 38 , wherein the embossing pattern comprises embossed horizontal lines running parallel to the TD of the membrane;
 wherein the horizontal lines have a line width of from 2 microns to 10 microns; and   wherein the horizontal lines have a spacing in the MD of from one to ten times the line width.   
     
     
         40 . The membrane of  claim 34 , wherein the microporous polymer film is formed from a polymer selected from polyolefins, fluorocarbons, polyamides, polyesters, polyacetals (or polyoxymethylenes), polysulfides, polyvinyl alcohols, co-polymers of the foregoing, or combinations of the foregoing. 
     
     
         41 . The membrane of  claim 40 , wherein the microporous polymer film is formed from a polyolefin, and wherein the polyolefin comprises polypropylene, polyethylene, or a combination thereof. 
     
     
         42 . The membrane of  claim 41 , wherein the polyolefin comprises impact copolymer polypropylene. 
     
     
         43 . The membrane of  claim 34 , wherein the plurality of pores have an average pore size of from 0.03 microns to 0.50 microns and an aspect ratio of from 0.75 to 1.25; and
 wherein the microporous polymer film has a porosity of from 20% to 80% and a TD tensile strength of at least 175 kg/cm2.   
     
     
         44 . The membrane of  claim 34 , wherein the microporous polymer film has at least one of a porosity of from 40% to 90%, a JIS Gurley of less than 100 seconds, a mean flow pore diameter of at least 0.04 microns, and an Aquapore size of at least 0.06 microns, a porosity of from 65% to 90%, a JIS Gurley of less than 60 seconds, a mean flow pore diameter of at least 0.05 microns, and an Aquapore size of at least 0.08 microns, a thickness of at least 8 microns and a TD tensile strength of at least 225 kg/cm2, a thickness of from 8 microns to 80 microns, and a TD shrinkage of less than 6.0% at 90° C. and less than 15.0% at 120° C. 
     
     
         45 . The membrane of  claim 34 , wherein the microporous polymer film comprises a multi-ply microporous polymer film. 
     
     
         46 . The membrane of  claim 34 , further comprising a nonwoven disposed on at least one side of the embossed microporous membrane. 
     
     
         47 . An embossed microporous membrane comprising an embossed microporous polymer film, wherein the embossed microporous membrane comprises embossed horizontal lines running parallel to the TD of the film;
 wherein the horizontal lines have a line width of from 2 microns to 10 microns; and   wherein the horizontal lines have a spacing in the MD of from one to ten times the line width.   
     
     
         48 . An embossed microporous membrane comprising an embossed microporous polymer film, wherein the embossed microporous polymer film has a thickness of from 2 microns to 20 microns, a porosity of from 20% to 65%, and a JIS Gurley of 500 or less. 
     
     
         49 . The membrane of  claim 48 , wherein the embossed microporous film has a ratio of MD tensile strength to TD tensile strength of from 0.5 to 5.0. 
     
     
         50 . The membrane of  claim 48 , wherein the embossed microporous polymer film is formed from polyolefins, fluorocarbons, polyamides, polyesters, polyacetals (or polyoxymethylenes), polysulfides, polyvinyl alcohols, co-polymers of the foregoing, or combinations of the foregoing. 
     
     
         51 . The membrane of  claim 48 , wherein the embossed microporous polymer film has at least one of a thickness of from 3 microns to 12 microns, a porosity of from 25% to 50%, a JIS Gurley of from 80 seconds to 500 seconds, a TD shrinkage of less than 6.0% at 90° C. and less than 15.0% at 120° C., a puncture strength of from 200 g to 325 g, a TD tensile strength of at least 250 kg/cm2, and an MD tensile strength of from 1000 kg/cm2 to 2000 kg/cm2. 
     
     
         52 . The membrane of  claim 48 , wherein the embossed microporous polymer film comprises a multi-ply embossed microporous polymer film. 
     
     
         53 . The membrane of  claim 48 , further comprising a nonwoven disposed on a side of the embossed microporous polymer film. 
     
     
         54 . A battery separator, material, textile, composite, or laminate comprising the membrane of  claim 34 . 
     
     
         55 . A battery separator, material, textile, composite, or laminate comprising the membrane of  claim 48 . 
     
     
         56 . An embossed microporous membrane comprising an embossed microporous polymer film, wherein the embossed microporous polymer is a dry process film. 
     
     
         57 . The membrane of  claim 56 , wherein the embossed microporous polymer film is formed from at least one of a polyolefin, and wherein the polyolefin comprises polypropylene, polyethylene, combinations thereof, or copolymers thereof. 
     
     
         58 . The membrane of  claim 56 , wherein the embossed microporous polymer film has at least one of a thickness of from 3 microns to 12 microns, a porosity of from 25% to 50%, a JIS Gurley of from 80 seconds to 500 seconds, a TD shrinkage of less than 6.0% at 90° C. and less than 15.0% at 120° C., a puncture strength of from 200 g to 325 g, a ratio of MD tensile strength to TD tensile strength of from 0.5 to 5.0, a TD tensile strength of at least 250 kg/cm2, and an MD tensile strength of from 1000 kg/cm2 to 2000 kg/cm2. 
     
     
         59 . The membrane of  claim 56 , wherein the embossed microporous polymer film comprises a multi-ply embossed microporous polymer film. 
     
     
         60 . The membrane of  claim 56 , further comprising a nonwoven disposed on a side of the embossed microporous polymer film. 
     
     
         61 . A battery separator, material, textile, composite, or laminate comprising the membrane of  claim 56 .