Improved micro layer film, improved battery separator, and associated method

Abstract

To provide a novel and improved multilayer micro porous film, base thin film or battery separator having various kinds of improvement such as an improved tension strength and an improved insulation breakdown strength.SOLUTION: Disclosed is a battery separator for lithium batteries including at least one micro porous separator film or sub film including a plurality of porous or micro porous polymer micro layers or nano layers. In the battery separator, at least one of individual micro layers or nano layers includes different or separate polymers, molecular mass polymers, homo polymers, copolymers and / or polymer blends in comparison with an adjacent individual micro layer or nano layer or includes a combination of different or separate polymers, molecular mass polymers, homo polymers, copolymers, polymer blends, additives, medicines, materials and / or fillers.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] Priority claim This application claims the benefit of and priority under 35 U.S.C. §119(e)(1) to both U.S. Provisional Patent Application No. 62 / 508,360, filed May 18, 2017, and U.S. Provisional Patent Application No. 62 / 420,781, filed November 11, 2016. Each of these provisional patent applications is incorporated herein by reference in its entirety.

[0002] According to at least selected embodiments, the present application, disclosure and inventions relate to new or improved membranes, separator films, separators, battery separators, lithium secondary battery separators, multilayer membranes, multilayer separator membranes, multilayer separators, multilayer battery separators, multilayer lithium secondary battery separators, and / or multilayer battery separators, new or improved batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or methods of making and / or using such membranes, separator films, separators, battery separators, lithium secondary battery separators, batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or devices, vehicles or products comprising same. According to at least certain embodiments, the present disclosure or inventions relate to new or improved membrane layers, membranes or separator films, battery separators comprising such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved porous polymer membranes or separator membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved microporous polyolefin membranes or separator membranes, microlayer membranes, multilayer membranes including one or more microlayers or nanolayer membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new, optimized, or improved microporous stretched polymer membranes or separator membranes having one or more new or improved outer and / or inner layers, microlayer membranes, multilayer microporous membranes or separator membranes having outer and inner layers, where some of such layers or sublayers are produced by coextrusion and then laminated together to form the new, optimized, or improved membrane or separator membrane.In some embodiments, a layer, microlayer, or nanolayer may comprise a homopolymer, copolymer, block copolymer, elastomer, and / or polymer blend. In selected embodiments, at least a layer, microlayer, or nanolayer may comprise a different or distinct polymer, homopolymer, copolymer, block copolymer, elastomer, and / or polymer blend. The present disclosure or invention also relates to new or improved methods of making such membranes, separator membranes, or separators and / or new or improved methods of using such membranes, separator membranes, or separators, for example, as lithium battery separators. According to at least selected embodiments, the present application or invention is directed to new or improved multilayer and / or microlayer porous or microporous membranes, separator membranes, separators, composites, electrochemical devices, and / or batteries, and / or methods of making and / or using such membranes, separators, composites, devices, and / or batteries. According to at least certain selected embodiments, the present application or invention is directed to new or improved multilayer separator membranes, wherein one or more layers of the multilayer structure are produced in a multi-layer or micro-layer coextrusion die having multiple extruders. The new or improved membranes, separator membranes, or separators may have improved shutdown, improved strength, improved It may preferably demonstrate improved dielectric breakdown strength and / or reduced tendency to split. [Background technology]

[0003] Known methods for making microporous bi- or tri-layer membranes for use as battery separator membranes include laminating or adhering two or more monolayer precursors together or simultaneously co-extruding more than one membrane layer using a co-extrusion die. Such methods are described, for example, in U.S. Pat. No. 5,952,120, U.S. Pat. No. 2014 / 0079980, U.S. Pat. No. 5,223,032, U.S. Pat. No. 5,240,655, and U.S. Pat. No. 2005 / 031943.

[0004] The above methods may not fully optimize the balance of strength and / or performance properties for use in certain primary and / or secondary battery applications, such as lithium-ion rechargeable batteries. This is especially true as battery separator requirements become more demanding as consumers desire thinner and stronger battery separators. For example, a microporous tri-layer membrane formed by coextrusion of three layers may have reduced strength. Separators formed by laminating single layers also ultimately cannot meet the ever-increasing demands. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, there is a need for new and improved multilayer microporous membranes, base films, or battery separators that have various improvements, such as improved tensile strength and improved dielectric breakdown strength. [Means for solving the problem]

[0006] According to at least selected embodiments, the present application, disclosure and invention may address the above-mentioned needs, challenges or problems and / or may provide new or improved membranes, separator membranes, separators, battery separators, lithium secondary battery separators, multilayer membranes, multilayer separator membranes, multilayer separators, multilayer battery separators, multilayer lithium secondary battery separators, and / or multilayer battery separators, new or improved batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or methods of making and / or using such membranes, separator membranes, separators, battery separators, lithium secondary battery separators, batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or devices, vehicles or products including same, having improved properties. According to at least certain embodiments, the present disclosure or invention relates to new or improved membrane layers, membranes or separator membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved porous polymer membranes or separator membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved microporous polyolefin membranes or separator membranes, microlayer membranes, multilayer membranes including one or more microlayers or nanolayer membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new, optimized, or improved microporous stretched polymer membranes or separator membranes having one or more new or improved outer and / or inner layers, microlayer membranes, multilayer microporous membranes or separator membranes having outer and inner layers, some of such layers or sublayers being produced by coextrusion and then laminated together to form the new, optimized, or improved membrane or separator membrane. In some embodiments, a layer, a microlayer, or a nanolayer is produced by coextrusion and then laminated together to form the new, optimized, or improved membrane or separator membrane. The microlayers or nanolayers may comprise homopolymers, copolymers, random copolymers, PP and / or PE copolymers, block copolymers, elastomers, and / or polymer blends. In selected embodiments, at least some layers, microlayers, or nanolayers may comprise different or distinct polymers, homopolymers, copolymers, block copolymers, elastomers, and / or polymer blends. The present disclosure or invention also relates to new or improved methods of making such membranes, separator membranes, or separators and / or new or improved methods of using such membranes, separator membranes, or separators, for example, as lithium battery separators. According to at least selected embodiments, the present application or invention is directed to new or improved multilayer and / or microlayer porous or microporous membranes, separator membranes, separators, composites, electrochemical devices, and / or batteries, and / or methods of making and / or using such membranes, separators, composites, devices, and / or batteries. According to at least certain selected embodiments, the present application or invention is directed to new or improved multilayer separator membranes, wherein one or more layers of the multilayer structure are produced in a multi-layer or micro-layer coextrusion die having multiple extruders. The new or improved membranes, separator membranes, or separators may preferably demonstrate improved shutdown, improved strength, improved dielectric breakdown strength, and / or reduced tendency to tear.

[0007] The microporous multilayer battery separators described herein, in some embodiments, exhibit improved safety, strength, and durability compared to previous bilayer, trilayer, or multilayer battery separators. For example, the separators may exhibit increased average dielectric breakdown (DB), increased minimum DB, increased shutdown speed, and increased flexure, all of which are indicative of a safer battery separator. The separators may also exhibit increased puncture strength and increased mixed penetration values, indicating stronger, more durable batteries.

[0008] These properties of the microporous multilayer battery separators described herein are at least partially a result of the method by which they are made. In some embodiments, the method includes at least coextruding two or more polymer mixtures to form a first coextruded bi-, tri-, or multi-layer film, coextruding two or more other polymer mixtures to form a second coextruded bi-, tri-, or multi-layer film, and coextruding two or more additional polymer mixtures to form a third coextruded bi-, tri-, or multi-layer film. Coextrusion typically involves using a coextrusion die with one or more extruders (typically one extruder per layer of the bi-, tri-, or multi-layer film) feeding the die. The polymer mixtures used to form each layer of the first, second, and third bi-, tri-, or multi-layer films can be the same or different. The mixtures can include one polymer or more than one polymer, e.g., polymer blends. Also, more than three bi-, tri-, or multi-layer films can be formed. After the first, second, and third bi-layer, tri-layer, or multi-layer thin films are formed, the thin films are laminated together with two of the thin films formed on opposite sides of one of the thin films to form the optionally preferred microporous battery separator described herein.

[0009] The microporous multilayer battery separators described herein can be used in lithium ion batteries, including lithium secondary batteries, resulting in batteries with improved safety and durability.

[0010] The battery separators herein can be described in several different ways.

[0011] In a first aspect, a battery separator for a lithium battery is described herein. In some embodiments, the battery separator includes at least one microporous separator membrane or sub-membrane comprising a plurality of porous or microporous polymeric micro- or nano-layers, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, random copolymers of ethylene and / or propylene, polymer blends, additives, agents, materials, elastomers, SEPS, SEBS, PVDF, EVOH, PMP, fillers, particles, ceramic particles, beads, fibers, scavengers, crosslinkers, adhesion promoters, surface modifiers, and / or combinations thereof, compared to adjacent individual micro- or nano-layers. In some embodiments, the plurality of polymeric micro- or nano-layers described above are laminated to each other or to the microporous polymeric membrane. In some embodiments, at least one of the separator membranes or sub-membranes of polymeric microlayers or nanolayers has at least three microlayers or nanolayers. Optionally, at least one of the separator membranes or sub-membranes of polymeric microlayers or nanolayers is made from one or more polyolefins. Optionally, at least one of the separator membranes or sub-membranes of polymeric microlayers or nanolayers is made from a coextruded dry-process polyolefin microlayer or nanolayer. In some embodiments, the separator membranes or sub-membranes have at least two of the polymeric microlayers or nanolayers. In some embodiments, the separator membranes or sub-membranes have at least three of the polymeric microlayers or nanolayers.

[0012] In another aspect, described herein is a lithium battery including any of the battery separators described immediately above.

[0013] In another aspect, improved separators, membranes, or base films are described herein. In some embodiments, the separator is a multilayer separator, membrane, or base film comprising one or more microporous coextruded micro- or nano-multilayer polymeric membranes or sub-membranes adapted to be laminated or adhered to another polymeric membrane, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, drug, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, drugs, materials, and / or fillers, compared to adjacent individual micro- or nano-layers.

[0014] In another aspect, described herein is a battery including at least one battery separator described in the preceding paragraph.

[0015] In another aspect, a battery separator or separator membrane is described herein. In some embodiments, the battery separator or separator membrane comprises one or more coextruded micro-multilayer membranes laminated or adhered to another polymeric membrane, and the separator or separator membrane may impart improved strength, such as improved puncture strength, particularly at a certain thickness, and may also exhibit improved shutdown and / or reduced tear tendency, and at least one of the individual microlayers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to adjacent individual microlayers.

[0016] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0017] In another aspect, battery separators or separator membranes are described herein. In some embodiments, the battery separators or separator membranes comprise one or more coextruded micro- or nano-multilayer membranes, optionally laminated or adhered to another polymeric membrane. The separators or separator membranes may exhibit improved strength, improved puncture resistance, and / or improved shutdown and / or reduced tear tendency at a given thickness. In some embodiments, at least one of the individual micro- or nanolayers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to adjacent individual micro- or nanolayers.

[0018] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0019] In another aspect, improved battery separators are described herein, including multilayer microporous thin films. In some embodiments, the multilayer microporous thin films include 9 or more layers, 12 or more layers, 15 or more layers, 18 or more layers, 21 or more layers, 24 or more layers, 27 or more layers, or 30 or more layers. In some embodiments, at least three consecutive layers of the microporous thin films have a thickness of 0.1 to 5 microns, 0.1 to 3 microns, 0.1 to 2.5 microns, or 0.1 to 2.0 microns. In some embodiments, the battery separator itself has a thickness of 1 micron to 30 microns, 2 microns to 20 microns, 3 microns to 15 microns, or 4 microns to 10 microns. In some embodiments, at least three consecutive layers each individually comprise a polyolefin or polyolefin blend; in some embodiments, each of these layers comprises polyethylene; and in some embodiments, each of these layers comprises polypropylene.

[0020] In some cases, the at least three consecutive layers are coextruded layers. In some embodiments, these at least three consecutive layers are laminated with at least one other layer to form a microporous polymeric thin film. In some embodiments, the at least one other layer is also a coextruded layer, coextruded with at least one other layer. In the battery separator described above, the at least one other layer is a coextruded layer. In some embodiments, the battery separator described has a puncture strength of 290 gf or greater, 300 gf or greater, or 310 gf or greater.

[0021] In another aspect, described herein are batteries, including lithium ion batteries, particularly lithium ion secondary batteries, that include one or more of the battery separators described in the preceding paragraphs. The batteries are at least more durable, particularly in embodiments in which the battery separator has a puncture strength of 290 gf or greater, 300 gf or greater, or 310 gf or greater.

[0022] In yet another aspect, a microporous multilayer battery separator is described herein, the battery separator comprising two or more layers, the first region comprising mostly discontinuous amorphous regions when viewed in the z-direction of the film using an SEM; and a second region comprising one layer. In some embodiments, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more of the amorphous regions in the first region are discontinuous. In some embodiments, the second region comprises two or more layers, preferably three or more layers, and an amorphous region having a maximum width of 0.8 microns, a maximum width of 0.7 microns, or a maximum width of 0.6 microns. In some of the embodiments described herein, at least one of the first and second regions comprises one or more layers comprising a polyolefin. In some embodiments, the first region comprises at least one layer comprising polyethylene, and the second region comprises at least one layer comprising polypropylene. Optionally, at least one of the first and second regions comprises a coextruded bi-, tri-, or multi-layer film. Optionally, the first region comprises a coextruded bi-, tri-, or multi-layer film. Optionally, the first region and the second region comprise a coextruded bi-, tri-, or multi-layer film. Optionally, the first region, second region, and third region of the microporous multilayer battery separator each comprise a coextruded bi-, tri-, or multi-layer thin film. Optionally, at least one of the second and third regions of the microporous multilayer battery separator comprises a coextruded bi-, tri-, or multi-layer thin film. Optionally, the second region comprises a coextruded bi-, tri-, or multi-layer thin film. Optionally, the third region comprises a coextruded bi-, tri-, or multi-layer thin film.

[0023] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0024] In another aspect, a battery separator includes a multilayer microporous thin film having an average dielectric breakdown (DB) value higher than that of a typical tri-layer microporous thin film having at least one of the same thickness, Gurley, and porosity as the multilayer microporous thin film. For example, the average DB value may be 1-35% higher, 5-35% higher, 10-35% higher, 15-35% higher, or 20-35% higher. In some embodiments, the DB minimum value of the microporous multilayer thin film of the battery separator described herein may be higher than that of a typical or conventional tri-layer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film. For example, the DB minimum value may be 3-20% higher, 5-15% higher, or 10-15% higher than that of a tri-layer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film. In some cases, the multilayer microporous thin film comprises 9 or more layers, 12 or more layers, 15 or more layers, 18 or more layers, 21 or more layers, 24 or more layers, 27 or more layers, or 30 or more layers. In some embodiments, at least one of such layers comprises a polyolefin or polyolefin blend. The polyolefin blend may be polyethylene or a polyethylene blend or polypropylene or a polypropylene blend. In some other embodiments, the multilayer microporous thin film having the dielectric breakdown values ​​herein may comprise a first region comprising two or more layers and a second region comprising at least one layer. The first region may comprise polypropylene and a largely discontinuous amorphous region when viewed in the z-direction of the film using an SEM. In some embodiments, the multilayer microporous thin film of a battery separator having the dielectric breakdown improvement described herein may comprise: (1) a first region comprising two or more layers, a second region comprising at least one layer, and a third region comprising at least one layer. The first region may comprise polypropylene and largely discontinuous amorphous regions when viewed in the z-direction (or thickness direction) of the film using an SEM.

[0025] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0026] In another embodiment herein, the porosity is 5 mL / g or less, 4.5 mL / g or less, at a pressure sufficient to cause mercury to fill the pores, as measured using mercury intrusion porosimetry. A battery separator comprising a multilayer microporous thin film that exhibits a mercury intrusion value of 4 mL / g or less, or a log differential intrusion value of 3.5 mL / g or less. In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0027] In another aspect, described herein is a battery separator comprising a multilayer microporous thin film having a MacMillan number greater than 5, greater than 5.5, greater than 6, greater than 6.5, greater than 7, greater than 8, greater than 9, or greater than 10. In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0028] In another aspect herein, a battery separator is described herein, comprising a multilayer microporous thin film having a tortuosity value of 1.6 or greater, 1.8 or greater, or 2.0 or greater. In some embodiments, the battery separator herein is a microporous battery separator. In some embodiments, the battery separator is a microporous multilayer battery separator.

[0029] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0030] In another embodiment, a battery separator comprising a multilayer microporous thin film that exhibits a pin removal force of less than 50 Newtons, 40 Newtons, 30 Newtons, 20 Newtons, 15 Newtons, or 10 Newtons.

[0031] In another aspect, a battery, particularly a lithium-ion battery, is described herein, comprising at least one membrane or separator as described in the preceding paragraph. The battery may preferably have a membrane or separator that is a dry-process or dry-stretch-process polyolefin-based membrane, particularly a blown or bubble-extruded MD-stretched or MD+TD-stretched membrane, although other membranes, such as slot-die extrusion or casting, wet-process, BNBOPP, BOPP, particle-stretched, and / or equivalent membranes, may be used. For example, a dry-process multilayer PO membrane may be laminated to a BNBOPP membrane.

[0032] In another embodiment, a battery separator is described herein. The battery separator includes a microporous multilayer thin film including: (1) a first region including two or more layers; (2) a second region including two or more layers on a first surface of the first region; and (3) a third region including two or more layers on a surface opposite the first surface of the first region, wherein at least one of the first, second, or third regions includes PE and has a lower crystallinity, as measured by DSC, than the PE-containing layer of the tri-layer microporous thin film, wherein the tri-layer microporous thin film has the same thickness as the multilayer microporous thin film. For example, the crystallinity may be 1 to 20% lower, 1 to 15% lower, 1 to 10% lower, or 1 to 5% lower.

[0033] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0034] In another aspect, described herein is a battery separator comprising a multilayer microporous thin film having a mixed penetration (N) value of greater than 380 N, greater than 400 N, greater than 450 N, greater than 500 N, greater than 550 N, greater than 600 N, greater than 650 N, or greater than 700 N.

[0035] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0036] In another aspect, a battery separator is described herein, which comprises a microporous thin film having an electrical resistance value of, in some embodiments, 2 or less, in some embodiments, 1.7 or less, in some embodiments, 1.6 or less, in some embodiments, 1.5 or less, in some embodiments, 1.4 or less, in some embodiments, 1.3 or less, in some embodiments, 1.2 or less, and in some embodiments, 1.0 or less.

[0037] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0038] In another embodiment, a battery separator is described that includes a multilayer microporous thin film having a mixed penetration value of 380 N or greater, 400 N or greater, 450 N or greater, 500 N or greater, 550 N or greater, 600 N or greater, 650 N or greater, or 700 N or greater.

[0039] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0040] In another aspect, a battery separator is described that includes a multilayer microporous thin film having an electrical resistivity of 2.0 or less, 1.7 or less, 1.6 or less, 1.5 or less, 1.4 or less, 1.3 or less, 1.2 or less, 1.1 or less, or 1.0 or less.

[0041] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0042] In another embodiment, a battery separator comprising a multilayer microporous thin film comprising two or more layers or microlayers and a region comprising polyethylene in one or more of the layers or microlayers, wherein said region, when tested according to the machine learning tests described herein, satisfies at least one of the following: W T x' ≥ -4, W T x' ≥ -2.654, W T x' ≥ 1.3, and W T x' ≥ 2, W T It is most preferred that x'≧2.

[0043] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0044] In another embodiment, a battery separator comprising a multilayer microporous thin film comprising two or more layers or microlayers and a region comprising polypropylene in one or more of the layers or microlayers, wherein said region, when tested according to the machine learning tests described herein, satisfies at least one of the following: W T x' ≥ -5, W T x' ≥ -3, W T x' ≧0, W T x' ≥ 3, W T It is most preferred that x'≧3.

[0045] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0046] In another embodiment, a battery separator comprising a multilayer or microporous thin film having the same thickness, porosity and breakdown uniformity that is better than Gurley's typical separator.

[0047] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0048] In another aspect, a battery separator is described. The battery separator includes at least one multilayer microporous membrane or thin film having at least two regions or sublayers, each region or sublayer comprising at least two microlayers, wherein the multilayer membrane has or exhibits at least one of the following: (a) a mixed penetration (N) value greater than 380 N; (b) a mixed penetration (N) value greater than 600 N; (c) a tortuosity greater than or equal to 1.8; (d) an average dielectric breakdown value (V) that is 1 to 35% higher than that of a tri-layer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous membrane; (e) a minimum dielectric breakdown value (V) that is 3 to 20% higher than that of a tri-layer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous membrane; and (f) a dielectric breakdown uniformity. (g) passes a nail penetration test; (h) has at least one microlayer comprising PO, PP and / or PE and an elastomer; (i) has at least one microlayer comprising a siloxane; (j) has at least one microlayer comprising PP and an elastomer; (k) has at least one microlayer comprising a copolymer; (l) has at least one microlayer comprising PP and a copolymer; (m) has at least two microlayers comprising different resins or resin blends; (n) when one of the above regions comprises polypropylene in one or more of the microlayers, at least one of the following is met when this region is tested according to the machine learning test described herein: W T x'≧- 5 or W T x'≧-3; (o) one of the above regions is in one or more of the microlayers When the region contains polypropylene, at least one of the following is met when the region is examined according to the dimensional reduction technique known as PCA described herein: T x' ≥ 0, and W T x'≧3; (p) when one of the above regions comprises polyethylene in one or more of the microlayers, when that region is tested according to the machine learning tests described herein, at least one of the following is satisfied: W T x' ≥ -4 and W T x'≧−2.654; (q) when one of the above regions comprises polyethylene in one or more of the microlayers, when that region is tested according to the machine learning tests described herein, at least one of the following is satisfied: W T x' ≥ 1.3, and W T x'≧2; (r) one of the above regions contains PE and (s) the microporous multilayer membrane or thin film has 30-100 microlayers or more; (t) at least one of the microlayers comprises lithium stearate; (u) the multilayer microporous thin film exhibits reduced MD or TD tearing; (v) at least one of the microlayers comprises PE beads; (w) has a pin removal of less than 50 N; (x) exhibits reduced contact with pins; (y) has reduced MD or TD tearing; (z) may be a precursor for at least one of transverse direction (TD) stretching, calendaring, and pore filling. In some embodiments, the microporous multilayer film exhibits 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 13 or more, 14 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, 20 or more, 21 or more, 22 or more, 23 or more, 24 or more, 25 or more, or 26 of 26 options. The separator may include other properties. In some embodiments, the battery separator is coated on one or more surfaces thereof, and in some embodiments, is uncoated. In some embodiments, the coating is a ceramic coating.

[0049] In another aspect, described herein are batteries, particularly lithium ion batteries, that include at least one separator as described in the preceding paragraph.

[0050] In another aspect, described herein is a method for forming an improved battery separator comprising a multilayer microporous membrane or thin film. The method comprises the steps of co-extruding at least two layers and bonding the at least two co-extruded layers to one or more other layers. In some embodiments, the method includes at least laminating the at least one other layer to two other layers to form a multilayer microporous membrane. In some embodiments, at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 layers are coextruded. In some embodiments, at least one other layer, or at least one of the at least two other layers, is a coextruded layer. In some embodiments, at least one of the other layers is a monoextruded layer. In embodiments in which at least two coextruded layers are laminated to two other layers, optionally, one of the other two layers is laminated to a first surface of the at least two coextruded layers, and a second of the other two layers is laminated to a surface opposite the first surface of the at least two coextruded layers. At least one of the other two layers may be a coextruded layer. In some embodiments, both of the other two layers are coextruded layers. In some embodiments, at least one of the at least two coextruded layers and the other layer comprise a polyolefin or polyolefin blend. For example, they may comprise polyethylene or a polyethylene blend or polypropylene or a polypropylene blend. In some embodiments, at least one of the at least two coextruded layers comprises polyethylene and at least one or both of the other layers comprises polypropylene or a polyethylene blend. In some embodiments, at least one of the at least two coextruded layers comprises polyethylene and at least one or both of the other layers comprises polypropylene or a polypropylene blend. In some embodiments, each of the other two layers comprises polyethylene or a polyethylene blend. In some embodiments, each of the other two layers comprises polypropylene or a polypropylene blend. In some embodiments, one or both of the other two layers is a coextruded layer coextruded with 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, or 9 or more other layers. When a layer is coextruded with 9 other layers, the total number of coextruded layers is 10. In another embodiment, a battery separator made by the method described in the preceding paragraph. [Brief explanation of the drawings]

[0051] [Figure 1] FIG. 1 is a partial cross-sectional scanning electron micrograph (SEM) at 2,500x magnification of an exemplary laminated three-layer or triple-layer microporous membrane of the present invention, trilayer / trilayer / trilayer (with nine coextruded microlayers for each trilayer and three microlayers for each PP or PE sublayer of each trilayer) (at least the outer PP layer of each layer is microporous). [Figure 2] Figure 2 is a partial cross-sectional scanning electron micrograph (SEM) at 15,000x magnification of a portion of the polypropylene surface sublayer (three microlayers of PP) of the surface tri-layer component or sub-membrane of the composite laminate membrane of Figure 1 (the PP sublayer is magnified and is actually three coextruded PP microlayers where it is difficult to discern the interfaces). [Figure 3] Figure 3 is a partial cross-sectional scanning electron micrograph (SEM) at 15,000x magnification of the polyethylene sublayer (three microlayers of PE) of the nine microlayer trilayers of the three-layer membrane in Figure 1 (the PE sublayer is enlarged). [Figure 4] FIG. 4 is a graph demonstrating the improved cycling behavior of an exemplary inventive structure compared to COM EX1. [Figure 5] FIG. 5 is a graph demonstrating the compressive elasticity results of certain structures compared to COM EX1. [Figure 6] FIG. 6 is a graph demonstrating Mix P penetration test results for a structure compared to COM EX1. [Figure 7] FIG. 7 is a schematic diagram of how microlayers can be created in a feedblock by layer accretion in a coextrusion process. [Figure 8] FIG. 8 is a schematic diagram of how microlayers can be created by delamination in a coextrusion process. [Figure 9]FIG. 9 is a cross-sectional scanning electron micrograph (SEM) at 5,000x magnification of an exemplary three-layer or tri-layer (nine microlayers total with three triple-microlayer sublayers laminated together) PP / PE / PP microporous membrane of the present invention (at least the outer PP sublayer is microporous). [Figure 10] Figure 10 is a surface scanning electron micrograph (SEM) at 3,000x magnification of the surface of the polypropylene surface sub-layer (surface PP microlayer) of the 9-microlayer, 3-layer membrane of Figure 9. This 9-microlayer membrane could be used as one layer of a 3-layer (9 sub-layer, 27 microlayer) membrane, for example, as shown in Figure 1. [Figure 11] FIG. 11 is a surface scanning electron micrograph (SEM) at 10,000× magnification of a portion of the surface of the polypropylene surface sublayer (surface PP microlayer) of the 9-microlayer, 3-layer membrane of FIG. [Figure 12] FIG. 12 is a surface scanning electron micrograph (SEM) at 30,000× magnification of a portion of the surface of the polypropylene surface sublayer (surface PP microlayer) of the 9-microlayer, 3-layer membrane of FIG. [Figure 13] Figure 13 is a cross-sectional scanning electron micrograph (SEM) at 5,000x magnification of an exemplary three "microlayer" coextruded sublayer (PO1 / PO2 / PO1) microporous membrane of the present invention, with microlayer PO2 made of a different resin or resin blend than microlayer PO1 (at least the outer PO1 microlayer is microporous), more clearly showing the interfaces (interface zones) of adjacent coextruded microlayers. The multiple coextruded microlayer interfaces and lamination interfaces between adjacent sublayers are believed to impart unique characteristics, properties, and / or performance to the multilayer structure of the present invention. The sublayers in the example of Figure 13 are made of three PP layers, with a central PP layer of a different PP resin than the outer two layers, which had to be made with a thicker precursor due to the lower viscosity of the central PP layer (typically, each microlayer was less than 4 μm, preferably less than 3 μm, and more preferably less than 2 μm). [Figure 14]FIG. 14 is a markup of a portion of the SEM of FIG. 13, showing the interface zone with red and green horizontal lines. [Figure 15] FIG. 15 is an enlarged version of FIG. 13, showing the unique pore and membrane structure. [Figure 16] Figure 16 is a schematic representation of an exemplary 12 μm trilayer according to at least one embodiment of the present invention (PP / PE / PP sublayers or microlayers laminated together, the sublayers being different from each other; the top PP sublayer has three coextruded PP microlayers, the middle PE sublayer has three PE microlayers that may be the same or different from each other, and the bottom PP sublayer has two PP blend microlayers and one PP microlayer). Figure 16 illustrates that many different embodiments are possible in a single, nine-microlayer membrane, and that variations in the sublayers and individual microlayers are possible and sometimes desirable. For example, some PP may need to be added in the outermost PP microlayer to increase adhesion, wettability, lamination bond strength, and / or the like. [Figure 17] Figure 17 is a schematic representation of an exemplary 3, 9, 18, or 21-microlayer embodiment or example of the present invention (blue represents PP microlayers, yellow represents PE microlayers, and numbered black lines indicate interfaces). Figure 17 illustrates that many different embodiments are possible, and that variations in the use of PP or PE sublayers are possible and sometimes desirable. For example, one might add some PE in the outer or center sublayers to increase adhesion, wettability, lamination bond strength, or to provide center shutdown functionality, and / or the like. [Figure 18] FIG. 18 shows improved DB uniformity data in some examples of multi-layer products (EX1, EX3, EX6) compared to other more conventional three-layer products. [Figure 19]Figure 19 is a graph demonstrating the improved cycling behavior of an exemplary inventive structure (EX1) compared to a conventional 12 µm trilayer product. The comparative film shown here is a 12 µm trilayer (PP / PE / PP) (no microlayer). This was performed at a C / 3 C rate with a 4.3 V cutoff at 523 NCM versus the graphite system. The data shown represents an average of five cells for each sample (or a total of 10 cells). We see repeatable improvements in cycle life with EX1 over the conventional trilayer, possibly due to improved electrolyte uptake due to increased interfacial and pore structure complexity. [Figure 20] FIG. 20 lists many non-limiting, exemplary embodiments, features, advantages, or configurations of the present multi-layer products and concepts. [Figure 21] 21 is a 10,000X cross-sectional SEM showing a 9-microlayer (each sublayer has 3 microlayers) PP / PE / PP sublayer that is about 14 um thick with a central PE sublayer that is about 3.11 um thick (each PE microlayer is only about 1.037 um thick). Using the present invention, microlayer structures can be created from polyolefin resins with microlayers each 2 um or less thick, microlayers each 1.5 um or less thick, microlayers each 1.3 um or less thick, microlayers each 1.15 um or less thick, microlayers each 1.05 um or less thick, and / or the like that perform better than other PO membranes. [Figure 22A] Figure 22A shows data for several examples of multi-layer products (EX1, EX3, EX2, EX4, and EX6) compared to other, more conventional, three-layer products (COM EX1, COM EX3, COM EX2, COM EX4). Normalization for thickness and porosity helps illustrate some of the benefits of the new multi-layer structure. [Figure 22B]Figure 22B shows data for several examples of multi-layer products (EX1, EX3, EX2, EX4, and EX6) compared to other, more conventional, three-layer products (COM EX1, COM EX3, COM EX2, COM EX4). Normalization for thickness and porosity helps illustrate some of the benefits of the new multi-layer structure. [Figure 23] Figure 23 shows further data for several examples of multilayer products (EX1, EX3, EX4, and EX6) compared to other, more conventional, three-layer products (COM EX1, COM EX3, COM EX2, COM EX4). Normalization for thickness and porosity helps illustrate some of the benefits of the new multilayer structure. Tortuosity was calculated by Nm = T2 / P, where Nm is the McMullin number, T is the tortuosity, and P is the porosity. [Figure 24] FIG. 24 includes an SEM image of a polypropylene layer of a multi-layer product according to some embodiments described herein. [Figure 25] FIG. 25 contains an SEM image of the polypropylene layer of a more conventional three-layer product described herein. [Figure 26] FIG. 26 includes an SEM image of a polyethylene layer of a multi-layer product according to some embodiments described herein. [Figure 27] FIG. 27 contains an SEM image of the polyethylene layer of a more conventional three-layer product described herein. [Figure 28] FIG. 28 contains SEM images showing a side-by-side comparison of the polypropylene layers of the tri-layer and multi-layer products described herein. [Figure 29] FIG. 29 contains SEM images showing a side-by-side comparison of the polyethylene layers of the tri-layer and multi-layer products described herein. [Figure 30] FIG. 30 includes SEM images showing a side-by-side comparison of the three-layer or multi-layer products described herein. [Figure 31] FIG. 31 is a table of DSC data for the polyethylene layers of the tri-layer and multi-layer products described herein. [Figure 32]FIG. 32 is a table of DSC data for the polypropylene layers of the tri-layer and multi-layer products described herein. [Figure 33] FIG. 33 is a graph showing a quantitative assessment of pore diameter distribution (using mercury intrusion porosimetry) of the tri-layer and multi-layer products described herein. [Figure 34] FIG. 34 shows the normalization of x to x′ (in PP) according to the machine learning tests described herein. [Figure 35] FIG. 35 shows the coefficients and boundary parameters (PP) from the machine learning experiments described herein. [Figure 36] FIG. 36 shows the normalization of x to x′ (in PE) according to the machine learning experiments described herein. [Figure 37] FIG. 37 shows the coefficients and boundary parameters (PE) from the machine learning experiments described herein. [Figure 38] FIG. 38 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 39] FIG. 39 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 40] FIG. 40 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 41] FIG. 41 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 42] FIG. 42 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 43] FIG. 43 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 44] FIG. 44 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 45] FIG. 45 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 46] FIG. 46 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 47] FIG. 47 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 48] FIG. 48 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 49] FIG. 49 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. [Figure 50] FIG. 50 is a representative schematic representation of a coextruded multilayer precursor, membrane or separator according to some further embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0052] The embodiments described herein may be more readily understood by reference to the following detailed description, examples, and figures. However, the elements, devices, and methods described herein are not limited to the specific embodiments presented in the detailed description, examples, and figures. It should be recognized that these embodiments are merely illustrative of the principles of the invention. Many changes and modifications will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention.

[0053] Additionally, all ranges disclosed herein should be understood to encompass any and all subranges contained therein. For example, a range stated as "1.0 to 10.0" should be considered to include any and all subranges beginning with a minimum value greater than or equal to 1.0 and ending with a maximum value less than or equal to 10.0, such as 1.0 to 5.3, or 4.7 to 10.0, or 3.6 to 7.9.

[0054] All ranges disclosed herein should also be considered to include the endpoints of the range, unless expressly stated otherwise. For example, a range "between 5 and 10," "from 5 to 10," or "5-10" is generally considered to include the endpoints 5 and 10. It should be.

[0055] Furthermore, when the phrase "up to" is used in conjunction with an amount or quantity, it should be understood that the amount is at least a detectable amount or quantity. For example, a material present in an amount "up to" a specified amount may be present from a detectable amount up to and including the specified amount.

[0056] Described herein are: microporous multilayer thin films or membranes; battery separators comprising at least one of the microporous multilayer thin films or membranes; batteries, particularly lithium ion batteries, comprising at least one of the battery separators described herein, devices comprising the batteries described herein, and methods of making the microporous multilayer thin films or membranes.

[0057] Multilayer (or multi-layer) microporous films or membranes exhibit improved properties, particularly when compared to previous tri-layer and multi-layer microporous films of the same thickness, Gurley, and / or porosity. Improved film or membrane properties include, but are not limited to, improved puncture strength (gf) compared to previous tri-layer (or trilayer) and multi-layer products, improved blend penetration average (N) compared to previous tri-layer and multi-layer products, improved elongation (kgf / cm) compared to previous tri-layer and multi-layer products, and improved elongation (kgf / cm) compared to previous tri-layer and multi-layer products. 2 ), faster shutdown rates (Ω-cm ) compared to previous tri-layer and multi-layer products. 2 ), higher average dielectric breakdown (DB) values ​​(V) compared to prior tri-layer and multi-layer products, lower DB standard deviations (V) compared to prior tri-layer and multi-layer products, higher minimum DB values ​​(V) compared to prior tri-layer and multi-layer products, passing industrial nail penetration tests where prior tri-layer and multi-layer microporous thin films failed, and improved cycle life compared to past tri-layer and multi-layer products. The multilayer microporous thin films herein were also found to have a unique structure. The unique structure of these thin films explains many of the improved properties observed.

[0058] Battery separator The battery separator herein comprises, consists of, or consists essentially of a (i.e., one or more) multilayer or multilayer microporous thin film and, optionally, a coating layer on one or both sides of the film. The thin film itself, i.e., the thin film without the coating or any other additional component, exhibits the improved properties described above. The performance of the thin film can be improved by the addition of a coating or other additional component.

[0059] (1) Multilayer microporous thin films or membranes In some embodiments, a multilayer or multilayer microporous thin film comprises 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, 11 or more, 12 or more, 13 or more, 14 or more, 15 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, 20 or more, 21 or more, 22 or more, 23 or more, 24 or more, 25 or more, 26 or more, 27 or more, 28 or more, 29 or more, 30 or more, 40 or more, 50 or more, 60 or more, 70 or more, 80 or more, 90 or more, or 100 or more layers. What is meant by the term "layer" is a monoextruded layer having a thickness of 2 to 20 microns. As will be understood by those skilled in the art, a monoextruded layer is a layer that is extruded by itself without any other layers. Also, each layer of a coextruded bilayer, trilayer, or multilayer thin film is considered a "layer" for purposes of determining whether a given battery separator is a multilayer battery separator. The number of layers in a coextruded two-layer is 2, the number of layers in a coextruded three-layer is 3, and the number of layers in a coextruded multilayer film is Two or more layers, preferably three or more. The exact number of layers in a bi-, tri-, or multi-layer coextruded film is determined by die design, not necessarily the materials coextruded to form the coextruded film. For example, a coextruded bi-, tri-, or multi-layer film may be formed using the same material to form each of two, three, or four or more layers, and these layers, even though each is made of the same material, are still considered separate layers. The exact number is similarly determined by die design. The layers of a coextruded bi-, tri-, or multi-layer film each have a thickness of 0.01 to 20 microns, preferably 0.1 to 5 microns, and most preferably 0.1 to 3 microns, 0.1 to 2 microns, 0.1 to 1 micron, 0.01 to 0.9 microns, 0.01 to 0.8 microns, 0.01 to 0.7 microns, 0.01 to 0.6 microns, 0.01 to 0.5 microns, 0.01 to 0.4 microns, 0.01 to 0.3 microns, or 0.01 to 0.2 microns. These layers are microlayers.

[0060] In some embodiments, the multilayer microporous thin films or membranes disclosed herein comprise two or more, or preferably three or more, coextruded layers. A coextruded layer is a layer formed by a coextrusion process. At least two, preferably at least three, consecutive coextruded layers may be formed by the same or separate coextrusion processes. For example, at least two or at least three consecutive layers may be formed by the same coextrusion process; two or more layers may be coextruded by a single process; two or more layers may be coextruded by separate processes; or two or more layers formed by a single process may be laminated to two or more layers formed by separate processes to combine four or more consecutive coextruded layers. In some preferred embodiments, two or more, or preferably three or more, coextruded layers are formed by the same coextrusion process. For example, two or more, or preferably three or more, four or more, five or more, six or more, seven or more, eight or more, nine or more, ten or more, fifteen or more, twenty or more, twenty-five or more, thirty-five or more, thirty-five or more, forty-five or more, fifty-five or more, fifty-five or more, or sixty or more coextruded layers may be formed by the same coextrusion process. In a further preferred embodiment, the extrusion process is carried out by extruding two or more polymer mixtures, which may be the same or different, without the use of a solvent. A preferred coextrusion process is a dry process, such as the Celgard® dry process.

[0061] In some embodiments, the multilayer microporous thin films or multilayer films described herein are made by forming a coextruded bilayer (two coextruded layers), trilayer (three coextruded layers), or multilayer (two or more, preferably three or more coextruded layers) thin film and then laminating the bilayer, trilayer, or multilayer thin film to at least one, but preferably two, other thin films. The at least one, but preferably two, other thin films can be nonwoven thin films, monoextruded thin films, or coextruded thin films. In preferred embodiments, the other thin films are coextruded thin films having the same number of coextruded layers as the coextruded bilayer, trilayer, or multilayer thin film. For example, when a coextruded trilayer thin film is formed, the other one is also a coextruded trilayer.

[0062] Lamination of a bi-, tri-, or multi-layer coextruded thin film with at least one other monoextruded mono-layer thin film or bi-, tri-, or multi-layer thin film may involve the use of heat, pressure, or preferably heat and pressure.

[0063] Polymers or copolymers that can be used in current battery separators are those that are extrudable. Such polymers are typically referred to as thermoplastic polymers.

[0064] In some embodiments, one or more of the layers of the multilayer microporous thin film or multilayer film comprises a polymer or copolymer, or a polymer or copolymer blend, preferably a polyolefin or polyolefin blend. A polyolefin blend, as understood by those skilled in the art, is a blend of two or more different types of polyolefins, such as It may include a mixture of polyethylene and polypropylene, a blend of two or more of the same type of polyolefin, each polyolefin having different properties, for example, an ultra-high molecular weight polyolefin and a low or ultra-low molecular weight polyolefin, or a mixture of a polyolefin with another type of polymer or copolymer, or any additives.

[0065] Polyolefins include, but are not limited to, polyethylene, polypropylene, polybutylene, polymethylpentene, copolymers thereof, and blends thereof. In some embodiments, the polyolefin can be an ultra-low molecular weight, low molecular weight, medium molecular weight, high molecular weight, or ultra-high molecular weight polyolefin, such as medium or high molecular weight polyethylene (PE) or polypropylene (PP). For example, ultra-high molecular weight polyolefins can have a molecular weight of 450,000 (450k) or more, e.g., 500k or more, 650k or more, 700k or more, 800k or more, 1,000,000 or more, 2,000,000 or more, 3,000,000 or more, 4,000,000 or more, 5,000,000 or more, 6,000,000 or more, etc. High molecular weight polyolefins can have a molecular weight in the range of 250k to 450k, e.g., 250k to 400k, 250k to 350k, or 250k to 300k. The medium molecular weight polyolefin may have a molecular weight of 150 to 250 kJ, e.g., 100 kJ, 125 kJ, 130 kJ, 140 kJ, 150 kJ to 225 kJ, 150 kJ to 200 kJ, or 150 kJ to 200 kJ. The low molecular weight polyolefin may have a molecular weight in the range of 100 kJ to 150 kJ, e.g., 100 kJ to 125 kJ. The ultra-low molecular weight polyolefin may have a molecular weight of less than 100 kJ. The above values ​​are weight average molecular weights. In some embodiments, higher molecular weight polyolefins may be used to increase the strength or other properties of the microporous multilayer membranes or batteries, including those described herein. In some embodiments, lower molecular weight polymers, e.g., medium, low, or ultra-low molecular weight polymers, may be beneficial. For example, without wishing to be bound by any particular theory, it is believed that the crystallization behavior of lower molecular weight polyolefins may result in microporous multilayer thin films with smaller pores resulting from at least the MD stretching process that forms the pores.

[0066] Exemplary thermoplastic polymers, blends, mixtures, or copolymers other than polyolefin polymers, blends, or mixtures include, but are not limited to, polyacetal (or polyoxymethylene), polyamides, polyesters, polysulfides, polyvinyl alcohol, polyvinyl esters, and polyvinylidene (PVDF, PVDF:HFP, PTFE, PEO, PVA, PAN, etc.). Polyamides (nylons) include, but are not limited to, polyamide 6, polyamide 66, nylon 10, 10, polyphthalamide (PPA), copolymers thereof, and blends thereof. Polyesters include, but are not limited to, polyester terephthalate, polybutyl terephthalate, copolymers thereof, and blends thereof. Polysulfides include, but are not limited to, polyphenyl sulfide, copolymers thereof, and blends thereof. Polyvinyl alcohols include, but are not limited to, ethylene-vinyl alcohol, copolymers thereof, and blends thereof. Polyvinyl esters include, but are not limited to, polyvinyl acetate, ethylene-vinyl acetate, copolymers thereof, and blends thereof. Polyvinylidenes include, but are not limited to: fluorinated polyvinylidenes (e.g., polyvinylidene chloride, polyvinylidene fluoride), copolymers thereof, and blends thereof. Various materials may be added to the polymer. These materials are added to modify or enhance the performance or properties of individual layers or the separator as a whole. Such materials include, but are not limited to: materials that may be added to lower the melting point of the polymer. Typically, multilayer separators contain layers designed to close pores at a predetermined temperature, blocking the flow of ions between the electrodes of the battery. This function is commonly referred to as shutdown.

[0067] In some embodiments, each layer of a multilayer microporous thin film or multilayer film comprises, consists of, or consists essentially of a different polymer or copolymer or polymer or copolymer blend. In some embodiments, each layer comprises, consists of, or consists essentially of the same polymer or copolymer or polymer or copolymer blend. In some embodiments, alternating layers of a multilayer microporous thin film or multilayer film comprise, consist of, or consist essentially of the same polymer or copolymer or polymer or copolymer blend. In other embodiments, some of the layers of a multilayer or microporous multilayer film comprise, consist of, or consist essentially of the same polymer or polymer blend, and some do not.

[0068] Although it may be preferred that each of the layers or microlayers comprise, consist of, or consist essentially of a polyolefin (PO), such as PP or PE, or PE+PP blends, mixtures, copolymers, etc., it is contemplated that other polymers (PY), additives, agents, materials, fillers, and / or particles (M), and / or the like may be added or used to form layers or microlayers, such as PP+PY, PE+PY, PP+M, PE+M, PP+PE+PY, PE+PP+M, PP+PY+M, PE+PY+M, PP+PE+PY+M, or blends, mixtures, copolymers, and / or the like.

[0069] Also, the same, similar, different, or different PP or PE or PE+PP polymers, homopolymers, copolymers, molecular weights, blends, mixtures, interpolymers, etc. may be used. For example, the same, similar, different, or different molecular weight PP, PE, and / or PP+PE polymers, homopolymers, copolymers, interpolymers, blends, mixtures, and / or the like may be used in each layer. Thus, the structure may include various combinations and subcombinations of PP, PE, PP+PE, PP1, PP2, PP3, PE1, PE2, PE3, PP1+PP2, PE1+PE2, PP1+PP2+PP3, PE1+PE2+PE3, PP1+PP2+PE, PP+PE1+PE2, PP1 / PP2, PP1 / PP2 / PP1, PE1 / PE2, PE1 / PE2 / PP1, PE1 / PE2 / PE3, PP1+PE / PP2, or other combinations or structures.

[0070] In some embodiments, one or more additives can be added to the outermost layer of a multilayer microporous thin film or film to improve its properties or the properties of a battery separator or battery containing the same. The outermost layer may comprise PE, PP, or PE+PP in addition to the additive. For example, additives such as lithium stearate, calcium stearate PE beads, siloxanes, and polysiloxanes may be added to improve pin removal (i.e., to reduce the coefficient of friction of the thin film or film).

[0071] Additionally, certain polymers, copolymers, or polymer or copolymer blends can be used in the outermost layer of a multilayer microporous thin film or membrane to improve its properties or the properties of the battery separator or battery containing it. For example, the addition of a high molecular weight polymer or copolymer in the outermost layer can improve puncture strength.

[0072] In a further embodiment, additives to improve oxidation resistance may be added to the outermost layer of the multilayer microporous thin film or membrane. The additives may be organic or inorganic, or polymeric or non-polymeric.

[0073] In some embodiments, the outermost layer of the multilayer film or membrane may comprise, consist of, or consist essentially of polyethylene, polypropylene, or a mixture thereof.

[0074] In some embodiments, a microporous multilayer thin film or membrane may comprise three or more distinct regions or sub-membrane areas. In preferred embodiments, one or more of the regions or sub-membrane areas may comprise, consist of, or consist essentially of two or more layers, which may or may not be coextruded layers. In some preferred embodiments, two or more layers are coextruded layers. In some embodiments, a laminated barrier exists between a region or sub-membrane area and an adjacent region or sub-membrane area. A laminated barrier is formed when two surfaces, for example, two surfaces of different thin films or layers, are laminated together using heat, pressure, but preferably heat and pressure. In some embodiments, the submembrane area has the following non-limiting structures: PP, PE, PP / PP, PP / PE, PE / PP, PE / PE, PP / PP / PP, PP / PP / PE, PP / PE / PE, PP / PE / PP, PE / PP / PE, PE / PE / PP, PP / PP / PP / PP, PP / PE / PE / PP, PE / PP / PP / PE, PP / PE / PP / PP. , PE / PE / PP / PP, PE / PP / PE / PP, PP / PE / PE / PE / PP, PE / PP / PP / PP / PE, PP / PP / PE / PP / PP, PE / PE / PP / PP / PE / PE, PP / PE / PP / PE / PP, PP / PP / PE / PE / PP / PP, PE / PE / PP / PP / PE / PE, PE / PP / PE / PP / PE / PP, PP / PE / PP / PE / PP / PE, PP / PP / PP / PE / PP / PP / PP, PE / PE / PE / PP / PE / PE / PE, PP / PE / PP / PE / PP / PE / PP, PE / PP / PE / PP / PE / PP / PE, PE / PP / PE / PP / PE / PP / PE / PP, PP / PE / PP / PE / PP / PE / PP / PE, PP / PP / PE / PE / PP / PP / PE / PE, PP / PE / P E / PE / PE / PE / PE / PP, PE / PP / PP / PP / PP / PP / PP / PE, PP / PP / PE / PE / PEPE / PP / PP, PP / PP / PP / PP / PE / PE / PE / PE, PP / PP / PP / PP / PE / PP / PP / PP / PP, PE / PE / PE / PE / PP / PE / PE / PE / PE, PP / PE / PP / PE / PP / PE / PP / PE / PP,PE / PP / PE / PP / PE / PP / PE / PP / PE, PE / PE / PE / PE / PE / PP / PP / PP / PP, PP / PP / PP / PP / PP / PE / PE / PE / PE, PP / PP / PP / PP / PP / P E / PE / PE / PE / PE, PE / PE / PE / PE / PE / PP / PP / PP / PP / PP, PP / PE / PP / PE / PP / PE / PP / PE / PP / PE, PE / PP / PE / PP / PE / PP / PE / PP / PE / PP, PE / PP / PP / PP / PP / PP / PP / PP / PP / PP / PP / PE, PP / PE / PE / PE / PE / PE / PE / PE / PE / PE / PE / PP, PP / PP / PE / PE / PP / PP / PP / PP / PP / PP, PE / PE / PP / PP / PP / PP / PP / PP / PP / PP / PP / PP / PE, PP / PP / PP / PE / PP / PP / PP / PP / PP / PP / PP / PE, PP / PP / PP / PP / PP / PP / PP / PP / PP / PE / PP, PP / PP / PP / PP / PP / PP / PP / PP / PE / PP / PE, PE / PE / PP / PP / PP / PP / PE / PP / PP / PE. PE, as used herein, refers to a layer or microlayer of a region or sub-membrane area, e.g., a coextruded layer or microlayer, that comprises, consists of, or consists essentially of PE. PP, as used herein, refers to a layer or microlayer of a region or sub-membrane area, e.g., a coextruded layer or microlayer, that comprises, consists of, or consists essentially of PP. The PE or PP in different layers or microlayers may be the same or different. Similar variations, including up to 50 layers or microlayers per region or sub-film area, particularly coextruded layers or microlayers, can be formed by suitable extrusion dies.

[0075] In one preferred embodiment, the coextruded precursor may have the structure (PP1 / PP2 / PP3), (PP3 / PP2 / PP1), (PP3 / PP3 / PP2 / PP1 / PP1), (PP3 / PP3 / PP2 / PP2 / PP1 / PP1), (PP3 / PP3 / PP3 / PP2 / PP2 / PP2 / PP1 / PP1 / PP1), etc.

[0076] PP1 is a mixture of homopolymer PP and any suitable polymer such as polysiloxane or siloxane. PP2 may be made from the same or different PP homopolymer as PP1, and from copolymers of PP. The PP copolymer may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 may be made from the same or different homopolymer PP as PP1 and PP2, and may also contain additives to modify the surface coefficient of friction, which may be the same or different from those used in PP1.

[0077] In other preferred embodiments, the coextruded precursor may have the structure (PP1 / PP2 / PP3), (PP3 / PP2 / PP1), (PP3 / PP3 / PP2 / PP1 / PP1), (PP3 / PP3 / PP2 / PP2 / PP1 / PP1), (PP3 / PP3 / PP3 / PP2 / PP2 / PP2 / PP1 / PP1), (PP3 / PP3 / PP3 / PP2 / PP2 / PP1 / PP1 / PP1), etc. PP1 may be any polypropylene blend. PP2 may be made from any PP block copolymer, including those described herein. PP3 may be made from the same or a different PP block copolymer as used in PP2.

[0078] The regions or submembrane areas may be arranged in any order to form a microporous multilayer membrane or a microporous multilayer thin film. For example, the microporous multilayer membrane or the microporous multilayer thin film may have the following non-limiting structures: (PP / PP)(PE / PE) / (PP / PP); (PE / PE)(PP / PP)(PE / PE); (PP / PE)(PP / PE)(PP / PE); (PP / PE)(PE / PP)(PE / PP); (PP / PP / PP)(PE / PE / PE)(PP / PP / PP); (PE / PE / PE)(PP / PP / PP)(PE / PE / PE); (PP / PE / PP)(PE / PP / PE)(PP / PE / PP); (PP / PP / PE)(PE / PE / PE)(PE / PP / PP); (PE / PE / PP)(PP / PP / PP)(PP / PE / PE); (PE / PP / PE) / (PP / PE / PP)(PE / PP / PE); (PP / PE / PP)(PE / PP / PE)(PP / PE / PP); (PP / PE / PP)(PP / PE / PP)(PP / PE / PP); (PP / PP / PP)(PP / PP / PP)(PP / PP / PP); (PE / PE / PE)(PE / PE / PE)(PE / PE / PE); (PE / PE / PE)(PP)(PE / PE / PE); (PP / PP / PP)(PE)(PP / PP / PP); (PE / PE / PE)(PP / PP)(PE / PE / PE); (PP / PP / PP)(PE / PE)(PP / PP / PP); (PE / PP / PE)(PP)(PE / PP / PE); (PP / PE / PP)(PE)(PP / PE / PP); (PE / PP / PE)(PP / PP)(PE / PP / PE); (PP / PE / PP)(PE / PE)(PP / PE / PP); (PP / PP / PP / PP)(PE)(PP / PP / PP / PP); (PE / PE / PE / PE)(PP)(PE / PE / PE / PE); (PP / PP / PP / PP / PP)(PE)(PP / PP / PP / PP / PP); (PE / PE / PE / PE / PE)(PP / PP)(PE / PE / PE / PE / PE); (PP / PP / PP / PP / PP)(PE / PE / PE / PE / PE)(PP / PP / PP / PP / PP); (PE / PE / PE / PE / PE / PE)(PP / PP / PP / PP / PP)(PE / PE / PE / PE / PE);(PP / PE / PP / PE / PP) (PE / PP / PE / PP / PE) (PP / PE / PP / PE / PP); (PE / PP / PE / PP / PP) (PP / PE / PP / PE / PP) (PE / PP / PE / PP / PE). Variations of the above may be used to form microporous multilayer thin films or membranes having up to 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 layers or microlayers;

[0079] The thickness of the microporous multilayer thin film or multilayer film is not particularly limited, but is preferably less than 50 microns, less than 40 microns, less than 30 microns, less than 25 microns, less than 20 microns, less than 19 microns, less than 18 microns, less than 17 microns, or less than 16 microns. , less than 15 microns, less than 14 microns, less than 13 microns, less than 12 microns, less than 11 microns, less than 10 microns, less than 9 microns, less than 8 microns, less than 7 microns, less than 6 microns, or less than 5 microns. This is the thickness of the multilayer thin film or membrane before any coatings or treatments are applied.

[0080] Microporous, as used herein, means that the average pore size of the thin film, membrane, or coating is 2 microns or less, preferably 1 micron or less, 0.9 microns or less, 0.8 microns or less, 0.7 microns or less, 0.6 microns or less, 0.5 microns or less, 0.4 microns or less, 0.3 microns or less, 0.2 microns or less, preferably 0.1 microns or less, 0.09 microns or less, 0.08 microns or less, 0.07 microns or less, 0.06 microns or less, 0.05 microns or less, 0.04 microns or less, 0.03 microns or less, 0.02 microns or less, or 0.01 microns or less. In a preferred embodiment, the pores may be formed, for example, by performing an expansion process on the precursor thin film, as is done, for example, in the Celgard® dry process.

[0081] In some preferred embodiments, the multilayer microporous thin film or membrane includes sub-membranes or regions comprising, consisting of, or consisting essentially of PE, which are microporous and have an average pore size between 0.03 and 0.1, preferably between 0.05-0.09, 0.05-0.08, 0.05-0.07, or 0.05-0.06.

[0082] In another preferred embodiment, the multilayer microporous thin film or membrane PP comprises sub-membranes or regions comprising, consisting of or consisting essentially of these, which are microporous and have an average pore size between 0.02 and 0.06, preferably between 0.03 and 0.05, more preferably between 0.04 and 0.05 or 0.03 and 0.04.

[0083] In some other preferred embodiments, the multilayer microporous thin film or membrane comprises sub-membranes or regions comprising, consisting of, or consisting essentially of PP, or comprises sub-membranes or regions comprising, consisting of, or consisting essentially of PE, and the average pore size of the PP sub-membrane or region is smaller than that of the PE sub-membrane or region.

[0084] The Gurley of the microporous multilayer films or membranes is not so limited and may have any Gurley that makes them acceptable for use as battery separators. In some embodiments, the microporous multilayer films or membranes described herein have a JIS Gurley (s / 100cc) of 150 or greater, 160 or greater, 170 or greater, 180 or greater, 190 or greater, 200 or greater, 210 or greater, 220 or greater, 230 or greater, 240 or greater, 250 or greater, 260 or greater, 270 or greater, 280 or greater, 290 or greater, 300 or greater, 310 or greater, 320 or greater, 330 or greater, 340 or greater, or 350 or greater.

[0085] The porosity of the microporous multilayer thin film is not particularly limited. For example, any porosity that can form an acceptable battery separator is acceptable. In some embodiments, the porosity of the thin film or membrane can be 10-60%, 20-60%, 30-60%, or 40-60%.

[0086] The microporous multilayer film or membrane may have an uncoated puncture strength as high as 290 gf or greater, 300 gf or greater, 310 gf or greater, 320 gf or greater, 330 gf or greater, 340 gf or greater, 350 gf or greater, or 400 gf or greater.

[0087] The microporous multilayer thin film or membrane may have any average dielectric breakdown consistent with the goals described herein. In some embodiments, the average dielectric breakdown value is improved over or higher than that of a tri-layer microporous thin film having at least one of the same thickness, Gurley, and porosity. For example, the average dielectric breakdown value may be 1-35% higher, 5-35% higher, 10-35% higher, 15-35% higher, 20-35% higher, 25-35% higher, or 30-35% higher than that of a tri-layer microporous thin film having the same thickness, Gurley, and / or porosity.

[0088] The minimum dielectric breakdown value of a microporous multilayer film or membrane is not particularly limited. In some embodiments, the minimum value may be improved (or even higher) than that of a tri-layer microporous membrane having the same thickness, Gurley, and / or porosity. For example, the minimum dielectric breakdown value may be 3-20% higher, 5-15% higher, 10-15% higher, 5-10% higher, 3-10% higher, 3-15% higher, 15-20% higher, 10-20% higher, or 5-20% higher than that of a tri-layer microporous membrane having the same thickness, Gurley, and / or porosity.

[0089] The standard deviation of the breakdown values ​​is also not particularly limited. In some embodiments, the standard deviation is improved (or lower) compared to a tri-layer microporous thin film having the same thickness, Gurley, and / or porosity. For example, the standard deviation may be 10-55% lower, 10-50% lower, 10-45% lower, 10-40% lower, 10-35% lower, 10-30% lower, 10-25% lower, 10-20% lower, or 10-15% lower.

[0090] Higher mean DB values, minimum DB values, and lower DB standard deviations indicate that the films can be used to provide safer battery separators and batteries. Dielectric breakdown is the voltage value at which current begins to flow across the insulator. Higher values ​​clearly indicate a separator that can withstand higher voltages. A higher minimum value is also important because a battery separator is only as safe as its weakest point. A higher mean value is not good if one point in the film breaks down at a lower value. The lower standard deviation of DB values ​​for the multilayer microporous thin films described herein indicates consistency in the safety of the microporous multilayer thin films described herein.

[0091] The mixed penetration average (N) of the microporous multilayer thin films or membranes described herein is also not so limited. For example, the mixed penetration value can be 380N or more, 390N or more, 400N or more, 410N or more, 420N or more, 440N or more, 450N or more, 460N or more, 470N or more, 480N or more, 500N or more, 510N or more, 520N or more, 550N or more, 560N or more, 580N or more, 600N or more, 620N or more, 640N or more, 660N or more, 680N or more, 690N or more, 700N or more, 710N or more, 720N or more, 740N or more, 750N or more, or 760N or more.

[0092] The MD shrinkage of the multilayer microporous thin films or membranes described herein is not particularly limited, but is preferably lower than that of conventional three-layer microporous thin films, e.g., the MD shrinkage (%) at 105°C is less than 3%, preferably less than 2.5%, more preferably less than 2% or less than 1.5%, and most preferably less than 1%.

[0093] The MD tensile strength of the microporous multilayer thin film is not particularly limited, but is preferably high, for example, 1800 kgf / cm 2 Super, 2000kgf / cm 2 Super, 2100kgf / cm 2 Super, 2200kgf / cm 2 Super, 2250kgf / cm 2 Super, 2300kgf / cm 2 Super, 2400kgf / cm 2 or over 2500 kgf / cm 2 It's super.

[0094] The MD elongation of microporous multilayer thin films is not particularly limited. In embodiments, it is greater than 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, or 60%.

[0095] The TD tensile strength of the microporous multilayer thin film is not particularly limited. For example, in some embodiments, the TD tensile strength is 120 kgf / cm 2 Above, 125kgf / cm 2 Above, 130kgf / cm 2 Above, 135kgf / cm 2 Over 140kgf / cm 2 Above, 145kgf / cm 2 Above, 150kgf / cm 2 Above, 155kgf / cm 2 Above, 160kgf / cm 2 Above, 165kgf / cm 2 Above, 170kgf / cm 2 Above, 175kgf / cm2 Above, 180kgf / cm 2 Above, 185kgf / cm 2 or more, or 190 kgf / cm 2 or more, or 195kgf / cm 2 That's all.

[0096] The TD elongation of the microporous multilayer thin film is not particularly limited and may be, for example, greater than 500%, greater than 550%, greater than 600%, greater than 650%, greater than 700%, greater than 750%, greater than 800%, greater than 850%, greater than 900%, greater than 950%, or greater than 1000%.

[0097] The shutdown temperature of the microporous multilayer thin film is not particularly limited, but is preferably 120° C. or higher, 130° C. or higher, 140° C. or higher, 150° C. or higher, 160° C. or higher, 170° C. or higher, 180° C. or higher, 190° C. or higher, or 200° C. or higher. The shutdown speed of the microporous multilayer thin film is not particularly limited, but is preferably 6,000 Ω-cm. 2 More than 7,000Ω-cm 2 More than 8,000Ω-cm 2 More than 9,000Ω-cm 2 More than 10,000Ω-cm 2 More than 11,000Ω-cm 2 More than 12,000Ω-cm 2 More than 13,000Ω-cm 2 More than 14,000Ω-cm 2 More than 15,000Ω-cm 2 More than 16,000Ω-cm 2 More than 17,000Ω-cm 2 More than 18,000Ω-cm 2 More than 19,000Ω-cm 2 or above 20,000 Ω-cm 2 That's all.

[0098] A higher shutdown speed also indicates a safer battery separator: the faster a battery can be shut down, the greater its ability to prevent thermal runaway.

[0099] In some embodiments, the microporous multilayer or thin films described herein may surprisingly exhibit increased strength performance, as defined by reduced tear or reduced tendency to tear, when compared to known battery separators of the same (or greater) thickness, particularly when compared to known dry process battery separators of the same (or greater) thickness. The improved tear or tear may be quantified by the test method disclosed herein as the Composite Tear Index (CSI), and new or improved separators formed from the films or thin films described herein may have an improved CSI.

[0100] Regarding the structural features of the microporous multilayer thin films and membranes described herein, in some embodiments, the tortuosity of the films is greater than 1.6, greater than 1.7, greater than 1.8, greater than 1.9, greater than 2.0, greater than 2.1, or greater than 2.2. While not wishing to be bound by any particular theory, it is believed that the observed tortuosity values, particularly values ​​greater than 2.0, 2.1, or 2.2, may be responsible for the increased puncture strength and mixed penetration averages disclosed herein. More tortuosity films are also believed to be safer when used as battery separators for lithium-ion batteries.

[0101] The McMullin number of the microporous multilayer thin films or membranes described herein is greater than 5.0, greater than 5.5, greater than 6.0, greater than 6.5, greater than 7.0, greater than 7.5, greater than 8.0, greater than 8.5, greater than 9.0, greater than 9.5, greater than 10.0, or greater than 10.5.

[0102] In some embodiments, the electrical resistivity of the microporous multilayer film or membrane is greater than 0.9, greater than 1.0, greater than 1.1, greater than 1.2, greater than 1.3, greater than 1.4, greater than 1.5, greater than 1.6, or greater than 1.7.

[0103] The crystallinity of the microporous multilayer thin films described herein has been found to differ from that of previous multilayer and trilayer thin films. For example, in some embodiments where a microporous multilayer thin film includes: (1) a first region including two or more layers; (2) a second region including two or more layers on a first surface of the first region; and (3) a third region including two or more layers on a surface opposite the first surface of the first region, at least one of the first, second, or third regions includes PE and has a lower crystallinity, as measured by DSC, than the PE-containing layer of the trilayer microporous thin film when the trilayer microporous thin film has the same thickness as the multilayer microporous thin film. For example, the crystallinity may be 1-20% lower, 1-19%, 1-18%, 1-17%, 1-16%, 1-15% lower, 1-14%, 1-13%, 1-12%, 1-11%, 1-10%, 1-9%, 1-8%, 1-7%, 1-6%, 1-5%, 1-4%, 1-3%, or 1-2% lower than the PE-containing layer of the tri-layer microporous thin film when the tri-layer microporous thin film has the same thickness as the multi-layer microporous thin film.

[0104] Another structural difference between the multilayer microporous thin films described herein and previous tri-layer and multilayer thin films can be seen using a scanning electron microscope. See, for example, Figures 25-31. For example, as shown in Figures 25-31, a multilayer microporous thin film or membrane can include at least a first region including two or more layers and a second region including at least one layer. The first region can include a largely discontinuous amorphous region when viewed in the z-direction of the film using an SEM. The term "majority" means that most, but not necessarily all, of the amorphous region in the first layer is discontinuous. This can mean that at least 50%, more than 50%, more than 60%, more than 70%, more than 80%, more than 90%, more than 95%, more than 99%, or 100% of the amorphous region in the first layer is continuous. "Discontinuous amorphous regions" means that, when a sample of the first layer is analyzed, for example, by SEM, the path of the amorphous regions is interrupted or blocked by crystalline (lamellar) regions along the entire thickness of the first layer. Discontinuous means that the path of the amorphous regions is interrupted or blocked by crystalline (lamellar) regions along the entire thickness of the first layer. The path of the amorphous regions does not circumnavigate the crystalline (lamellar) regions. Instead, the crystalline (lamellar) regions completely interrupt the path of the amorphous regions along the entire thickness of the first layer. The path of the amorphous regions may be linear or circuitous. An example of the difference between discontinuous and continuous amorphous regions can be seen by comparing the SEM of the polyethylene layer of COM EX4 with the SEM of the polyethylene layer RO397 in Figure 29. Discontinuous can also mean that the amorphous regions are non-columnar, non-vertically continuous, or non-pillar-like along the thickness of the layer. In some preferred embodiments, the first region, which is a predominantly discontinuous amorphous region, may comprise, consist of, or consist essentially of polypropylene in some or all of the layers in that region. In some other embodiments, the second region comprises two or more layers, and the amorphous area of ​​that region of the film or membrane has a maximum width of 0.85 microns, 0.8 microns, 0.75 microns, 0.70 microns, 0.65 microns, or 0.6 microns.For example, this can be seen by comparing COM EX4 with R037 in Figure 30. In some preferred embodiments, the second region may comprise, consist of, or consist essentially of polyethylene in some or all of the layers in that region.

[0105] (2) Optional Coating In some embodiments, one or more coating layers may be applied to one or two sides of a microporous membrane or thin film to form a battery separator. In some embodiments, one or more of the coatings may include or contain a polymeric binder and organic and / or inorganic particles. The ceramic coating may consist of, or consist essentially of, a ceramic coating. In some embodiments, only the ceramic coating is applied to one or both sides of the microporous membrane or thin film. In other embodiments, a different coating may be applied to the microporous membrane or thin film before or after application of the ceramic coating. A different additional coating may also be applied to one or both sides of the membrane or thin film. In some embodiments, the different polymeric coating layer may comprise, consist of, or consist essentially of at least one of polyvinylidene difluoride (PVdF) or polycarbonate (PC).

[0106] In some embodiments, the thickness of the coating layer is less than about 12 μm, optionally less than 10 μm, optionally less than 9 μm, optionally less than 8 μm, optionally less than 7 μm, or optionally less than 5 μm. In at least certain selected embodiments, the coating layer is less than 4 μm, less than 2 μm, or less than 1 μm.

[0107] The coating method is not particularly limited, and the coating layer described herein can be coated onto the porous structure by at least one of the following coating methods: extrusion coating, roll coating, gravure coating, printing, knife coating, air knife coating, spray coating, dip coating, or curtain coating. The coating process can be carried out at room temperature or at an elevated temperature.

[0108] The coating layer may be any one of non-porous, nanoporous, microporous, mesoporous, or macroporous. The coating layer may have a JIS Gurley of 700 or less, optionally 600 or less, 500 or less, 400 or less, 300 or less, 200 or less, or 100 or less.

[0109] One or more layers, treatments, materials, or coatings (CT) and / or nets, meshes, mats, wovens, or nonwovens (NW) may be added to one or both sides of or within the multilayer films or membranes (M) described herein, which may include CT / M, CT / M / CT, NW / M, NW / M / NW, CT / M / NW, CT / NW / M / NW / CT, CT / M / NW / CT, etc.

[0110] method The method for forming the multilayer microporous thin films or membranes described herein is not so limited and can be a dry process, preferably the CELGARD® dry-stretch process, a dry process such as BNOPP, or a wet process utilizing a solvent or oil.

[0111] The method of forming the multilayer microporous thin film or membrane described herein comprises at least the following steps: (1) co-extruding two or more polymer mixtures, which may be the same or different, to form a co-extruded thin film, as described herein above, having two or more layers or microlayers; (2) laminating the co-extruded thin film to at least one other mono-extruded thin film, co-extruded thin film, or nonwoven fabric, and in some preferred embodiments, the co-extruded thin film is laminated to two other co-extruded thin films having two or more microlayers; and (3) optionally, one or more further steps.

[0112] (1) Co-extrusion process Coextrusion is not so limited. An exemplary coextrusion process is shown in Figure 7, and a coextrusion die is shown in Figure 8. In some embodiments, a coextrusion die is used with one or more extruders feeding the die. Typically, there is one extruder for each desired layer or microlayer of the ultimately formed coextruded film. For example, if the desired coextruded film has three microlayers, three extruders are used with the coextrusion die. In at least one embodiment, the membranes of the present invention may be comprised of many microlayers or nanolayers, with the final product containing as many as 50 or more individual microlayers or nanolayers. In at least some embodiments, the microlayer or nanolayer technology may be effected by a pre-encapsulation feedblock prior to entering a cast or blown film die.

[0113] In some preferred embodiments, the coextrusion is a bubble coextrusion process, and the blowing ratio can vary from 0.5 to 2.0, preferably from 0.7 to 1.8, and most preferably from 0.9 to 1.5. After coextrusion using this blowing ratio, the film can be MD stretched, MD stretched and then TD stretched (with or without MD relaxation), or simultaneously MD and TD stretched. The film can optionally be calendered to further control porosity.

[0114] Benefits of coextrusion include, but are not limited to, an increase in the number of layers (interfaces), which is believed to improve puncture strength, without wishing to be bound by any particular theory. Coextrusion is also believed to result in observed improvements in DB, without wishing to be bound by any particular theory. Specifically, the improved DB may be related to the reduced PP pore size observed when a coextrusion process is used. Coextrusion also allows for a wider range of material options by incorporating blends into microlayers. Coextrusion also allows for the formation of thin tri- or multi-layer films (coextruded films). For example, tri-layer coextruded films with thicknesses of 8 or 10 microns or less can be formed. Coextrusion allows for higher MD elongation and different pore structures (less PP, more PE). Coextrusion can be combined with lamination to create the desired multilayer structures of the present invention. For example, structures are formed as shown in the examples.

[0115] The minimum achievable thickness is determined by the extrusion process. In some examples, the thinnest PP microlayer may be about 0.19 mil (about 4.83 um sublayer), and the PE about 0.17 mil (about 4.32 um sublayer), with 0.19 mil or 0.17 mil for each of the three PP and PE microlayers, respectively. For one example 21-layer structure, the inventors suggest that a total extrusion thickness of 1.31 mil (33 um) may have about 1.14 mil of PP (or 0.57 mil on each side) and 0.17 mil of PE. The inventors believe that it may be possible to produce a 21-layer product of only 30 um or less with this configuration.

[0116] (2) Lamination Lamination is not so limited and includes bringing a surface of a coextruded thin film together with a surface of at least one other thin film and using heat, pressure, and / or heat and pressure to secure the two surfaces together. Heat can be used, for example, to increase the viscosity of either or both surfaces of the coextruded thin film and at least one other thin film, making lamination easier and thereby making the two surfaces tacky and better able to adhere together.

[0117] In some preferred embodiments, the laminate formed by laminating the coextruded thin film to at least one other thin film serves as a precursor for subsequent MD and / or TD stretching steps, with or without relaxation. In some embodiments, the coextruded thin film is stretched prior to lamination.

[0118] (3) Further processing The further steps may comprise, consist of, or consist essentially of MD, TD, or sequential or simultaneous MD and TD stretching steps. The stretching step may be performed before or after the stretching step. Stretching may be performed with or without MD and / or TD relaxation. Co-pending and commonly owned U.S. Patent Application Publication No. US2017 / 0084898A1, published March 23, 2017, is hereby incorporated by reference in its entirety.

[0119] Other additional steps may include calendaring. For example, in some embodiments, a calendaring step may be performed as a means of reducing the pore size and / or porosity and / or thickness as a means of further improving the transverse direction (TD) tensile strength and / or puncture strength of the porous biaxially stretched membrane precursor. Calendaring may also improve strength, wettability, and / or uniformity, and may also reduce surface layer defects that may be introduced during the manufacturing process, for example, during the MD and TD stretching processes. Calendared thin films or membranes may have improved coatability (using smooth calendar rolls). In addition, the use of textured calendaring rolls may aid in improved coating adhesion to the thin film or membrane.

[0120] Calendering can be cold (below room temperature), ambient (room temperature), or hot (e.g., 90°C) and can involve the application of pressure or the application of heat and pressure to controllably reduce the thickness of the film or thin film. Calendering can be in one or more steps, for example, low-pressure calendering followed by calendering at higher pressure, cold calendering followed by hot calendering, and / or the like. Additionally, the calendering process can use at least one of heat, pressure, and speed to densify the heat-sensitive material. Additionally, the calendering process can selectively densify the heat-sensitive material using uniform or non-uniform heat, pressure, and / or speed (e.g., using smooth rolls, rough rolls, patterned rolls, micropatterned rolls, nanopatterned rolls, speed variations, temperature variations, pressure variations, humidity variations, double roll processes, multi-roll processes, or combinations thereof) to impart uniform or non-uniform calendering conditions to produce improved, desired, or unique structure, characteristics, and / or performance, and to create or control the resulting structure, characteristics, and / or performance, and / or the like.

[0121] Another additional step may include pore filling. The pore filling step is not so limited and may be performed in any manner consistent with the goals described herein. For example, in some embodiments, the pores may be partially or completely coated, treated, or filled with a pore filling composition, material, polymer, gel polymer, layer, or deposition (PVD). Preferably, the pore filling composition covers 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, etc., of the surface area of ​​the pores. The pore filling composition may comprise, consist of, or consist essentially of a polymer and a solvent. The solvent may be any suitable solvent useful for forming a composition for coating or filling pores, including an organic solvent such as octane, water, or a mixture of an organic solvent and water. The polymer may be any suitable polymer, including an acrylate polymer or a polyolefin, including a low molecular weight polyolefin. The concentration of polymer in the pore-filling composition is not particularly limited as long as the viscosity of the pore-filling composition is such that the composition is capable of coating the walls of the pores of any of the porous biaxially stretched precursor membranes disclosed herein, but may be between 1% and 30%, between 2% and 25%, between 3% and 20%, between 4% and 15%, between 5% and 10%, etc. Pore filling increases either or both the machine direction (MD) and transverse direction (TD) tension.

[0122] Composites, vehicles, or devices A battery separator as described hereinabove and one or more electrodes, such as an anode, a cathode, or an anode and a cathode, disposed in direct contact therewith. The type of electrode is not particularly limited. For example, the electrode may be one suitable for use in a lithium-ion secondary battery.

[0123] Suitable anodes may have an energy capacity of 372 mAh / g or greater, preferably ≥ 700 mAh / g, and most preferably ≥ 1000 mAh / g. The anodes are composed of lithium metal foil or lithium alloy foil (e.g., lithium aluminum alloy), or mixtures of lithium metal and / or lithium alloy with materials such as carbon (e.g., coke, graphite), nickel, or copper. The anodes are not simply made of lithium-containing intercalation compounds or lithium-containing insertion compounds.

[0124] Suitable cathodes may be any cathode compatible with the anode and may include intercalation compounds, insertion compounds, or electrochemically active polymers. Suitable intercalation materials include, for example, MoS2, FeS2, MnO2, TiS2, NbSe3, LiCoO2, LiNiO2, LiMn2O4, VO 13 , V2O5, and CuCl2. Suitable polymers include, for example, polyacetylene, polypyrrole, polyaniline, and polythiophene.

[0125] Any of the separators described herein above can be incorporated into any vehicle, such as an electric vehicle, or device, such as a cell phone or laptop computer, that is fully or partially battery powered.

[0126] Various embodiments of the present invention have been described in order to achieve various objects of the present invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Many changes and modifications will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention. [Example]

[0127] Preparation of Examples Inventive (multi-layer) products were prepared and compared to comparative (tri-layer) products, primarily with reference to the following Examples 1-10 and Comparative Examples 1-5. The multi-layer products were formed by the methods described herein, including co-extruding three separate films comprising three coextruded layers, and laminating the three films together. The tri-layer products were formed by forming three separate extruded monolayer films and laminating the monolayers together.

[0128] The microlayer composition of the product of the present invention prepared is as follows:

[0129] Example 1 (EX1) - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - All PP layers made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE.

[0130] Example 2 (EX2) - (PP1 / PP2 / PP1) (PE1 / PE2 / PE3) (PP1 / PP2 / PP1) - PP1 is a homopolymer PP. PP2 is a homopolymer polypropylene with a higher MFR than PP1. PE1 is a high density polyethylene with a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190°C. PE2 is an ultra high density polyethylene. PE3 is a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190°C, and a viscosity of 0.955 to 0.966 g / cm. 3 95% high density polyethylene with a density range of 5% It is a blend with mLLDPE.

[0131] Example 3 (EX3) - (PP / PP / PP) (PE1 / PE2 / PE1) (PP / PP / PP) - PP layer consists of homopolymer PP, density = 0.90 g / cm 3 , with MFR ranging from 0.5MFR to 2MFR. PE1 is made of high density polyethylene with a melt index between 0.25 and 0.5g / 10min at 2.16kg and 190℃. PE2 is made of ultra-high molecular weight polyethylene.

[0132] Example 4 (EX4) - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - All PP layers made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a density of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density in the range of 100-1500 and 5% mLLDPE.

[0133] Example 5 (EX5) - PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - All PP layers made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a density of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density in the range of 100-1500 and 5% mLLDPE.

[0134] Example 6 (EX6) - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - PP is made of homopolymer PP, density = 0.90 g / cm 3 , with an MFR ranging from 0.5MFR to 2MFR. PE is made of high density polyethylene with a melt index between 0.25 and 0.5g / 10min at 2.16kg and 190℃.

[0135] Example 7 - (EX7) - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - All PP layers made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a density of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density in the range of 100-1500 and 5% mLLDPE.

[0136] Example 8 (EX8) - (PP1 / PP2 / PP1) (PE1 / PE2 / PE1) (PP1 / PP2 / PP1) PP1 is homopolymer PP, density = 0.90 g / cm 3 , with an MFR ranging from 0.5 MFR to 2 MFR. PP2 is made of homopolymer PP with an MFR of 0.25 and a density of 0.9. PE1 is a high-density polyethylene with a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190°C. PE2 is an ultra-high molecular weight polyethylene.

[0137] Example 9 (EX9) - (PP1 / PP2 / PP1) (PE / PE / PE) (PP1 / PP2 / PP1) - PP1 is made of homopolymer PP, density = 0.90 g / cm 3 , and MFR in the range of 0.5MFR to 2MFR. PP2 has a density of 0.90g / cm 3 , is a blend of 95% homopolymer PP with a MFR ranging from 0.5 MFR to 2 MFR and 5% propylene-ethylene copolymer. PE is a blend of 92% high-density polyethylene with a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190°C and 8% olefin block copolymer.

[0138] Example 10 (EX10) - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - All PP layers made of homopolymer PP, density = 0.90 g / cm 3All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a density of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density in the range of 100-1500 and 5% mLLDPE. The layer composition of one comparative product was prepared as follows:

[0139] Comparative Example 1 (COM EX1) - (PP)(PE)(PP) - All PP layers are made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE.

[0140] Comparative Example 2 (COM EX2) - (PP)(PE)(PP) - All PP layers were made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE.

[0141] Comparative Example 3 (COM EX3) - (PP)(PE)(PP) - All PP layers were made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE.

[0142] Comparative Example 4 (COM EX4) - (PP)(PE)(PP) - All PP layers were made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE.

[0143] Comparative Example 5 (COM EX5) - (PP)(PE)(PP) - All PP layers were made of homopolymer PP, density = 0.90 g / cm 3 All PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190 °C, and a viscosity of 0.955 to 0.966 g / cm 3 It is made of a blend of 95% high density polyethylene with a density range of 1000 psi and 5% mLLDPE. Referring primarily to Figures 38-50 and further multi-layer embodiments, further Examples 11-38 are as follows:

[0144] Example 11 - Each PP and PE layer of the three-layer structure is itself made of multiple layers, preferably coextruded and then laminated - (PP / PP / PP) (PE / PE / PE) (PP / PP / PP) - all PP layers are made of homopolymer PP, density = 0.90 g / cm 3 If all PE layers have a melt index between 0.25 and 0.5 g / 10 min at 2.16 kg and 190°C, the MFR ranges from 0.5 MFR to 2 MFR. and density 0.955-0.966g / cm 3 It is made of a blend of 95% high density polyethylene with a density in the range of 100-1500 and 5% mLLDPE.

[0145] Example 12 - (PP1 / PP2 / PP3) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same as or a different blend or block copolymer from PP1, PP2.

[0146] Example 13 - (PP1 / PP1) or (PP2 / PP2) or (PP1 / PP2) - PP1 is a polypropylene blend and PP2 is a PP block copolymer.

[0147] Example 14 - (PP1 / PP1 / PP1) or (PP2 / PP2 / PP2) - PP1 is a polypropylene blend and PP2 is a PP block copolymer.

[0148] Example 15 - (PP1 / PP2 / PP3) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0149] Example 16 - (PP3 / PP2 / PP1) / (PP3 / PP2 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0150] Example 17 - (PP1 / PP2 / PP3) / (PP3 / PP2 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0151] Example 18 - (PP1 / PP2) / (PP3 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0152] Example 19 - (PP1 / PP2 / PP3 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0153] Example 20 - (PP1 / PP2 / PP3) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 contains an adhesion promoter.

[0154] Example 21 - (PO3 / PP2 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PO3 is a polyolefin blend (e.g., PP+PE).

[0155] Example 22 - (PP1 / PP2 / PP3) - PP1 is a homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1, including a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as in PP1 and PP2 plus a surface coefficient of friction (COF)-modifying additive that may be the same or different as used in PP1.

[0156] Example 23 - (PP3 / PP2 / PP1) - PP1 is the homopolymer PP + PP1 and PP2 are homopolymer PPs that may include any slip or block additive, such as siloxane, that modify the coefficient of friction (COF). PP2 is the same or different homopolymer PP as used in PP1 and PP3, and includes copolymer PPs that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 includes homopolymer PPs that may be the same or different from those in PP1 and PP2 plus a surface coefficient of friction modifying additive, the same or different from that used in PP1.

[0157] Example 24—(PP3 / PP2 / PP1) or (PP1 / PP2 / PP3)—PP1 is homopolymer PP plus additives described herein, which may include any slip or block additives, such as siloxanes, that modify the coefficient of friction (COF). PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus copolymer PP, which may be any propylene, ethylene, or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus copolymer PP, which may be any propylene, ethylene, or ethylene-propylene random copolymer, block copolymer, or elastomer.

[0158] Example 25: A co-extruded PP precursor is proposed with the structure shown in Figure 41.

[0159] The surface modification additives may include any slip or anti-block additive such as siloxane. The copolymer may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer or elastomer.

[0160] The coextruded PP precursor can be extruded at a blow-under-pressure (BUR) ratio anywhere between 0.9 and 1.5 to control porosity. The coextruded PP precursor is then either sequentially MD-then TD-oriented or simultaneously biaxially oriented. The biaxially oriented film can be further calendered to control porosity.

[0161] Example 26: A second proposed structure can be made as shown in Figure 44 for battery separator or textile applications.

[0162] This structure allows the design of a surface layer with a higher degree of flexure for water barrier in high-velocity water tests.

[0163] The types of copolymers that can be incorporated into the structure include, but are not limited to, propylene-ethylene or ethylene-propylene random copolymers, block copolymers or elastomers.

[0164] By extruding PP in a coextrusion format, the surface characteristics of the PP layer can be modified, while a lower melting copolymer resin interlayer can be incorporated to lower the shutdown temperature. Different copolymer resins can also be incorporated anywhere in the structure to control the porosity of the TD stretched film.

[0165] Incorporating BURs into the precursor film allows for further control of the porosity required for various applications.

[0166] Example 27 - (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0167] Example 28 - (PP3 / PP2 / PP1) / (PP3 / PP2 / PP1) / (PP3 / PP2 / PP1) - PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0168] Example 29 - (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0169] Example 30 - (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0170] Example 31 - (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) (PP3 / PP2 / PP1) PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0171] Example 32 - (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) PP1 is a polypropylene blend, PP2 is a PP block copolymer, and PP3 is the same or a different PP block copolymer.

[0172] Example 33 - (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) - PP1 is a homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus a surface coefficient of friction modifying additive, the same or different from that used in PP1.

[0173] Example 34—(PP3 / PP2 / PP1) / (PP3 / PP2 / PP1) / (PP3 / PP2 / PP1)—PP1 is homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus copolymer PP, which may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus a surface coefficient of friction modifying additive, the same or different from that used in PP1.

[0174] Example 35 - (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) PP1 is a homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus a surface coefficient of friction modifying additive, the same or different from that used in PP1.

[0175] Example 36 - (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) PP1 is homopolymer PP + modified coefficient of friction as described herein. PP1 is a homopolymer PP that may be the same or different from those used in PP1 and PP2, plus a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is a homopolymer PP that may be the same or different from those used in PP1 and PP2, plus a surface coefficient of friction modifying additive that may be the same or different from that used in PP1.

[0176] Example 37 - (PP1 / PP2 / PP3) (PP3 / PP2 / PP1) (PP3 / PP2 / PP1) PP1 is a homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus a surface coefficient of friction modifying additive that may be the same or different from that used in PP1.

[0177] Example 38 - (PP3 / PP2 / PP1) (PP1 / PP2 / PP3) (PP1 / PP2 / PP3) PP1 is a homopolymer PP plus additives described herein that may include any slip or block additive, such as siloxane, that modifies the coefficient of friction. PP2 is the same or different homopolymer PP as used in PP1 and PP3 plus a copolymer PP that may be any propylene-ethylene or ethylene-propylene random copolymer, block copolymer, or elastomer. PP3 is the same or different homopolymer PP as used in PP1 and PP2 plus a surface coefficient of friction modifying additive, the same or different from that used in PP1.

[0178] The composition of one comparative product may be as follows (preferably of about the same thickness, same thickness and porosity, or same thickness, porosity and Gurley as the inventive example being compared, and / or may be normalized for porosity and / or Gurley): Comparison 6 - Typical monolayer PP (e.g., Celgard 2500) Comparison 7 - Typical Three-Layer Laminate (PP / PE / PP) Comparison 8 - Typical ceramic coated version of typical single layer PP or typical three layer (PP / PE / PP)

[0179] Characterization of Examples - Separator Properties and Battery Performance Thickness (μm) Thickness is measured in micrometers μm using an Emveco Microgage 210-A micrometer thickness tester and test procedure ASTM D374. The thicknesses of Examples 1-6 and Comparative Examples 1-4 were determined and are reported in the tables in Figures 22 and 23. Comparative Examples with thicknesses comparable to the Examples were prepared so that the separators could be meaningfully compared.

[0180] Basic weight (mg / cm 2 ) The basis weights of Examples 1-6 and Comparative Examples 1-4 were determined and are reported in the table in FIG.

[0181] JIS Gurley (s / 100cc) Gurley is defined herein as in the Japanese Industrial Standard (JIS) Gurley and is measured herein using an OHKEN permeability tester. JIS Gurley is the permeability required for 100 cc of air to pass through a 1 square inch membrane at a constant pressure of 4.9 inches of water. The time during which the resistance is reached is defined in seconds. JIS Gurley was measured for Examples 1 to 6 and Comparative Examples 1 to 4. The results are reported in the table in FIG.

[0182] MD shrinkage rate (%) at 105℃ / 1 hour Shrinkage is measured by placing a test sample between two pieces of paper, which are then clamped together, holding the sample between the papers, and suspending it in an oven. For the "105°C for 1 hour" test, the sample is placed in an oven at 105°C for 1 hour. After the specified heating time in the oven, each sample is removed and taped to a flat opposite surface using double-sided adhesive tape, the sample is flattened and smoothed, and the exact length and width are measured. Shrinkage is measured in both machine direction (MD) and transverse direction (TD), and is expressed as MD shrinkage (%) and TD shrinkage (%).

[0183] The MD shrinkage rates of Examples 1 to 6 and Comparative Examples 1 to 4 were measured and are reported in the table in FIG.

[0184] MD tensile strength (kgf / cm 2 ) The machine direction (MD) tensile strength is measured using an Instron Model 4201 according to the ASTM-882 procedure. The MD tensile strengths of Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG.

[0185] MD elongation (%) MD elongation at break (%) is the percentage of the elongation of the test sample along the machine direction of the test sample measured at the maximum tensile strength required to break the sample. The MD elongations of Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG.

[0186] TD tensile strength (kgf / cm 2 ) The transverse direction (TD) tensile strength is measured according to the ASTM-882 procedure using an Instron Model 4201. The TD tensile strengths of Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG.

[0187] TD elongation (%) The TD elongation at break (%) is the percentage of the elongation of the test sample along the transverse direction of the test sample measured at the maximum tensile strength required to break the sample. The TD elongation of Examples 1-6 and Comparative Examples 1-4 was measured and is reported in the table in Figure 22.

[0188] Puncture strength (gf) Puncture strength is measured using an Instron Model 4442 in accordance with ASTM D3763. Measurements are taken across the width of the microporous membrane, and puncture strength is defined as the force required to puncture the test sample. The puncture strengths of Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG. 22.

[0189] One idea is to use UHMW polymers to increase puncture strength. However, these polymers, which may have molecular weights greater than 1,000,000, cause processing difficulties, especially when the process is a dry process such as the CELGARD® dry process. Utilizing these technologies can alleviate the need to use polymers with molecular weights greater than 1 M, which can be very difficult to process, especially in dry process membranes.

[0190] DB average (V) A voltage is applied to the separator membrane until dielectric breakdown of the sample is observed. A strong separator exhibits a high DB. Any non-uniformity in the separator membrane will cause a lower DB value. A battery separator with a higher average DB, and especially a higher minimum DB value, will make the battery safer when used in a battery. The average DBs of Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG. 22.

[0191] DB minimum value (V) A voltage is applied to the separator membrane until dielectric breakdown of the sample is observed. A strong separator exhibits a high DB. Any non-uniformity in the separator membrane will cause a lower DB value. A battery separator with a higher average DB, and especially a higher minimum DB value, will make the battery safer when used in a battery. The minimum DB values ​​for Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG. 22.

[0192] DB uniformity The DB values ​​of Examples 1, 4, and 5 were compared with Comparative Examples 1, 2, and 4. The results are shown in Figure 18. The DB standard deviations were calculated and are reported.

[0193] Mixed penetration average (N) Mixed penetration is the force required to cause a short circuit through a separator when placed between a cathode material and an anode material. This test is used to indicate the tendency of a separator to cause a short circuit during battery assembly. Details of this method are described in US2010 / 209758, which is incorporated herein in its entirety. Mixed penetration values ​​were calculated for Examples 1-6 and Comparative Examples 1-4 and are reported in the table in FIG. 22.

[0194] Nail penetration test Examples 1-9 and Comparative Examples 1-5 were tested, and Examples 1 and 6 passed the nail penetration test. None of the Comparative Examples passed the nail penetration test. Nail penetration tests at velocities of 1 cm / sec and 10 cm / sec are described in U.S. Pat. No. 9,065,152, the entirety of which is incorporated herein by reference.

[0195] Shutdown temperature (℃) Shutdown start temperature is 100W×cm 2 Resistance readings were recorded and reported in °C. Shutdown temperatures for Examples 1-6 and Comparative Examples 1-4 were measured and are reported in the table in FIG.

[0196] Shutdown Speed ​​(Ω-cm 2 ) The example membrane is sandwiched between two nickel discs and wetted with PC solvent. The wetted separator stack is then subjected to a temperature ramp of 60°C / min. The resistance between the two nickel discs is monitored by a multimeter for the duration of the test. The shutdown definition for this test is a resistance of 100 W x cm. 2 ~10,000W×cm 2 The result for shutdown speed is W × cm, normalized by the time required for this resistance increase. 2 The shutdown speeds are reported in units of / second. The shutdown speeds of Examples 1 to 6 and Comparative Examples 1 to 4 were measured and are reported in the table in FIG.

[0197] ER(Ω-cm2 ) The ER method uses an electrolyte solution composed of a solvent mixture of DI water and 2-propanol. Electrical resistance is evaluated by sequentially adding four circular separator disks (38 mm diameter) between two metal electrodes. The separator resistance is measured in Ω using an LCR meter and then multiplied by the area of ​​the electrodes to obtain Ω-cm. 2 Obtain the electrolyte solution. The resistivity is measured using a YSI meter.

[0198] calculation: 1) Average separator resistance of successive separator layers, (Ω) = (R 層4 Omega-R 層3 Ω+R 層3 Omega-R 層2 Ω / 2 2) Electrical resistance, Ω-cm 2 = average resistance of successive separator layers Ω * Area of ​​nickel-plated electrode cm 2

[0199] The QC-ER was determined for Examples 1 to 6 and Comparative Examples 1 to 4. The results are reported in the table in FIG.

[0200] McMullin number Electrical resistivity (ER) measurements are used to calculate the McMullen number. The calculation is as follows: McMullen number = (electrical resistivity, Ω-cm 2 / Separator thickness, cm) / Electrolyte resistivity (Ω-cm).

[0201] The McMullin numbers were determined for Examples 1 to 6 and Comparative Examples 1 to 4. They are reported in the table in FIG.

[0202] Cycle Life All cycling was performed in constant current (CC) mode. The cathode used was 523NMC. The anode used was superior graphite. The electrolyte was 1 M LiPF6 salt in a 3:7 v:v EC:EMC solvent. The voltage window was 3.0–4.3 V. Cycles 1–5 were charged and discharged at C / 10 rates. Cycles 6–10 were charged and discharged at C / 5 rates. Cycles 11–15 were charged at C / 5 rates and discharged at C / 2 rates. Cycles 16–20 were charged at C / 5 rates and discharged at 1C rates (charge / discharge rate capacity; 1C is the full charge or discharge rate in 60 minutes). Cycles 21–25 were charged at C / 5 rates and discharged at 5C rates. Cycles 26–30 were charged at C / 5 rates and discharged at 10C rates. Cycles 31–35 were charged and discharged at C / 10 rates.

[0203] The cycle life of Example 1 and Comparative Example 1 was compared. This was done at a C rate of C / 3 with a cutoff of 4.3 V at 523 NCM for the graphite system. The data shown represents the average of five cells for each sample (or a total of 10 cells). The results are shown in Figure 19. While not wishing to be bound by any particular theory, this is likely due to improved electrolyte uptake resulting from increased interfaces, e.g., layer interfaces, and the complexity of the pore structure. This testing demonstrates a repeatable improvement in cycle life for the multilayer product compared to the conventional trilayer.

[0204] Compression Elasticity Compressive modulus was evaluated using a TMA Q400 and a hemispherical probe. A 5 mm x 5 mm sample was compressed at a constant rate up to 1 N (568 N / cm2), then the pressure was released by returning to 0 N at a constant rate at ambient temperature. The percentage of dimensional change during compression and recovery is estimated based on the initial thickness of the sample. Example 1 and Comparative Example 1 were tested for compressive resilience. The results are reported in Figure 5 and Table 1 below.

[0205] [Table 1]

[0206] The microlayer structure imparts higher compression recovery than comparable wet process membranes. In certain applications, less squeeze and / or better compression recovery may be desirable.

[0207] Pin removal Pin removal data for installations was collected using a pin removal winding machine. The machine was equipped with a 45 mm slit roll, and the separator roll was mounted on a split pin mandrel (4 mm diameter) on the machine. The separator was wound onto the mandrel and the pins were pulled apart. The maximum removal force was recorded and reported in Newtons. For each test sample, the outer diameter was held constant, and the film tension and length varied based on film thickness. It is best to compare films of the same or nearly the same thickness.

[0208] Characterization of Examples—Structural Properties AQ porosity (%) The porosity of the microporous thin film samples was measured using ASTM method D-2873 and is defined as the percentage of voids in the microporous membrane measured in both the machine direction (MD) and the transverse direction (TD). The AQ porosity for Examples 1-6 and Comparative Examples 1-4 was calculated and is reported in the table in Figure 22. Some additional porosity data for Example 1 was determined and is reported in Table 2 below:

[0209] [Table 2]

[0210] Aquaporeporosity(%) The Aquapore (AQ) porosity for Examples 1-6 and Comparative Examples 1-4 was measured and is reported in the table in FIG.

[0211] AQ PP pore diameter (μm) Pore ​​size is measured using an Aquapore available through Porous Materials Inc. (PMI). Pore size is expressed in μm. AQ PP pore sizes for Examples 1-6 and Comparative Examples 1-4 were calculated and are reported in the table in FIG. 22. Further data for Examples 1, 9, and 10 was obtained and is reported in Table 2.

[0212] AQ PE pore diameter (μm) Pore ​​size is measured using an Aquapore available through Porous Materials Inc. (PMI). Pore size is expressed in μm. AQ PE pore sizes for Examples 1-6 and Comparative Examples 1-4 were determined and are reported in the table in FIG. 22. Further data for Examples 1, 9, and 10 were determined and are reported in Table 2.

[0213] AQ surface area (m 2 / g) Aquapore is a water intrusion measurement technique that is only available for testing base membranes. In this measurement, a large area of ​​the membrane is immersed in water and pressurized to 3,000 psi. The results of the test are the overall porosity of the membrane (reported in %), the pore size of the PP and / or PE (reported in μm), and the inner and outer surface area of ​​the pores (m 2 The aquapore surface area was determined for Examples 1-6 and Comparative Examples 1-4 and is reported in the table in Figure 22. Further data was determined for Examples 1, 9, and 10 and is reported in Table 2.

[0214] Pore ​​diameter distribution The pore diameter distributions of Examples 6 and 11 and Comparative Example 4 were measured using mercury intrusion porosimetry. The results are shown in Figure 33. The pore diameters in Comparative Example 4 were larger than those in the inventive examples and had a narrower distribution.

[0215] Calculated bending degree. The degree of bending was calculated by the following formula (1): N m =T 2 / P(1), In the formula, N m is the McMullin number, T is the tortuosity, and P is the porosity. While not wishing to be bound by any particular theory, it is believed that battery separators with higher tortuosity are safer. The reason for this is believed to be that it is more difficult for dendrites to grow between the electrodes due to the more tortuous path that growing dendrites must take to travel from the anode to the cathode. The calculated tortuosities for Examples 1-6 and Comparative Examples 1-4 are given in the table in FIG. 23.

[0216] SEM image 1. Processing conditions Procedure for cross-sectional observation using a scanning electron microscope (SEM). a.) Cut the sample to an appropriate size (a few mm square). b.) Ion milling produces a flat cross section (MD-ND plane). Ion milling equipment: E-3500 (Hitachi High-Technologies Corporation.) Ion source: Ar+ Accelerating voltage: 3.5 kV Discharge voltage: 2.0 kV Stage control: 5 (setting value) Processing time: 4 hours Temperature: 20~25℃ c.) The sample is attached to a stub using double-sided carbon conductive tape and carbon paste. d.) Apply an osmium plasma coating to make the sample conductive. 2. SEM observation conditions a.) Equipment: S-4800 (Hitachi High-Technologies Corporation.) Acceleration voltage: 1 kV Working distance: approx. 5 mm

[0217] SEM images were taken of Examples 1, 2, 4, and 6 and Comparative Examples 1, 4, and 5. Some of these images are shown in Figures 24-30. It was found that there were distinct structural differences between the multilayer products in the Examples and the three-layer products in the Comparative Examples. For example, the PP layers of the three-layer products contained more columnar or vertically continuous amorphous regions, while the amorphous regions of the multilayer PP regions (having three layers of PP in the Examples) were largely discontinuous and non-columnar. Side-by-side comparisons in Figures 28-30 illustrate these differences between the multilayer and three-layer products.

[0218] Machine Learning Exam Detailed Steps 1: Image feature extraction to obtain vectors for machine learning ·Read image by OpenCV python module cv2 Obtain 50 240x160 pixel subimages at uniformly random positions from either the PP or PE region, and normalize the images using cv2.normalize with α=0, β=255, and norm_type=cv2.NORM_MINMAX. To become. For each subimage, use the SIFT feature detector cv2.x features 2d.SIFT_create with default settings to obtain features with angle and size. Convert each angle a of the obtained features to a'=90-|a mod 180-90|. For i from 1 to 9, called the bin count, [10 * (i-1), 10 * Count the number of angles a' transformed in the range [i] Concatenate the bin count, average feature size (a scalar), and number of features (a scalar) to obtain the feature vector x k (11 dimensions) (kth image) · Take the median values ​​of 11 features from the 50 partial images and use them as the feature vector x of the input image.

[0219] Rules for the OpenCV python module cv2 include Python Machine Learning by Raschka (ISBN 1783555130) and OpenCV by Python Blueprints by Michael Beyeler (1785282697), both of which are incorporated herein by reference in their entirety. Further information on OpenCV can be found at https: / / en.wikipedia.org / wiki / OpenCV

[0220] Example of PP layer: After obtaining the feature vector x from the PP layer by step 1 described below, each value x in x is converted into the following mean vector m=[0.121252742025, 0.0932702969461, 0.0637613832138, 0.0471628522627, 0.0410994787666, 0.0455612990903, 0.0663893557564, 0.143913936237, 0.373695714612, 3.470413863, 569.8305 08475] and standardized as x'=(xm) / s using standard deviation vector s=[0.0177890460233, 0.0126226741459, 0.0109280746046, 0.00952236047605, 0.00919810029221, 0.00802167410741, 0.00965575771023, 0.0135729399588, 0.0556357096109, 0.181326979354, 52.6681415756] · Let w be [-2.29884147179, -0.120953660963, 0.609748975014, -0.354807579078, 0.0742943451505, -0.0596756155513, 0.679531409197, 1.18484320645, 0.639551068782, -0.123277373445, 0.495565514875], and the dot product is w T Calculate x' ·w T If x'>-1.27465281948, classify the image as 9 layers.

[0221] Example of PE layer: After obtaining the feature vector x from the PE layer by step 1 described below, each value x in x is converted into the following mean vector m=[0.0753659021681, 0.0647442404474, 0.052445934828, 0.0441842705626, 0.0424971059836, 0.0495261454071, 0.0745156791392, 0.15315494777, 0.434028151238, 3.51412063686, 480.021 73913] and standardized as x'=(xm) / s using standard deviation vector s=[0.0212709138539, 0.0156303526361, 0.0100887199823, 0.00610554172426, 0.00588628646619, 0.00509466227247, 0.00868424601387, 0.0177249443105, 0.0499726205047, 0.217925555283, 60.5317430669] w [0.0026717153, -0.2072501509, -0.4883326802, 0.0172248418, -0.5467527574, -0.389222 5728, 0.7356477088, 1.1574408691, -1.1992044378, -1.920101147, 0.1068808983, 0.6542173447] and the dot product is w T Calculate x' ·w T If x'>-0.6542173447, classify the image as 9 layers.

[0222] Examples 1, 2, 4, 7, 8, and 10, and Comparative Examples 1, 4, and 5 were subjected to machine learning testing to determine whether the comparative (three-layer) examples and the inventive (multi-layer) examples could be distinguished by this testing. The results are shown in Figures 34 to 37. The comparative (three-layer) examples and the inventive (multi-layer) examples could be distinguished.

[0223] DSC DSC analysis was performed to determine the melting point (T m ) and the onset of crystallization are determined. A Netzsch DSC200F3 model is used with a sealed aluminum sample holder with a perforated lid. Nitrogen is used as the carrier gas at 40 ml / min to prevent sample oxidation. The mass of the analyzed samples varies between 5 and 6 mg. T m To determine the onset of crystallization and the thermal history, the samples are first subjected to a heat treatment to erase the thermal history. The instrument then performs another heating and cooling cycle at 10°C / min starting from 25°C to 300°C. Data acquisition and handling is performed by Proteus Analysis software. Examples 1, 3, 5, and 6 and Comparative Examples 1, 2, 3, and 4 were evaluated by DSC. The PE and PP layers were evaluated separately. The results are shown in Figures 31 and 32.

[0224] According to at least selected embodiments, the present application, disclosure and inventions relate to new or improved membranes, separator films, separators, battery separators, lithium secondary battery separators, multilayer membranes, multilayer separator membranes, multilayer separators, multilayer battery separators, multilayer lithium secondary battery separators, and / or multilayer battery separators, new or improved batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or methods of making and / or using such membranes, separator films, separators, battery separators, lithium secondary battery separators, batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or devices, vehicles or products comprising same. According to at least certain embodiments, the present disclosure or inventions relate to new or improved membrane layers, membranes or separator films, battery separators comprising such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved porous polymer membranes or separator membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new or improved microporous polyolefin membranes or separator membranes, microlayer membranes, multilayer membranes including one or more microlayers or nanolayer membranes, battery separators including such membranes, and / or related methods. According to at least certain embodiments, the present disclosure or invention relates to new, optimized, or improved microporous stretched polymer membranes or separator membranes having one or more new or improved outer and / or inner layers, microlayer membranes, multilayer microporous membranes or separator membranes having outer and inner layers, where some of such layers or sublayers are produced by coextrusion and then laminated together to form the new, optimized, or improved membrane or separator membrane.In some embodiments, a layer, microlayer, or nanolayer may comprise a homopolymer, copolymer, block copolymer, elastomer, and / or polymer blend. In selected embodiments, at least a layer, microlayer, or nanolayer may comprise different or distinct polymers, homopolymers, copolymers, block copolymers, elastomers, and / or polymer blends. The disclosure or invention also relates to new or improved methods of making such membranes, separator membranes, or separators, and / or new or improved methods of using such membranes, separator membranes, or separators, for example, as lithium battery separators. According to at least selected embodiments, the present application or invention is directed to new or improved multilayer and / or microlayer porous or microporous membranes, separator membranes, separators, composites, electrochemical devices, and / or batteries, and / or methods of making and / or using such membranes, separators, composites, devices, and / or batteries. According to at least certain selected embodiments, the present application or invention is directed to new or improved separator membranes that are multilayered, where one or more layers of the multilayer structure are produced in a multilayer or microlayer coextrusion die having multiple extruders. The above-described new or improved membranes, separator membranes, or separators may preferably demonstrate improved shutdown, improved strength, improved dielectric breakdown strength, and / or reduced tendency to tear.

[0225] According to at least selected embodiments, this application or invention is directed to additives for improved battery performance, improved additive-containing membranes, improved battery separators, and / or improved batteries, and / or related improved methods of manufacture and / or use thereof. According to at least certain embodiments, this application or invention is directed to additive-containing membranes, separator membranes, and / or battery separators, and / or methods of making and / or using such membranes, separator membranes, and / or battery separators. According to at least certain embodiments, this application or invention is directed to the incorporation of additives into microporous or separator membranes for use in lithium secondary batteries, e.g., lithium-ion secondary batteries, improved battery separators, and / or related methods. In some embodiments, the membranes may contain additives that improve performance in battery chemistries, e.g., in lithium-ion batteries. In other selected embodiments, the membranes may contain additives, such as siloxanes or lithium stearate, that improve pin removal performance. In certain other embodiments, the present invention may also relate to methods of making such membranes or separator membranes, and methods of using such membranes or separator membranes, for example, as lithium battery separators. According to at least selected embodiments, the present application or invention is directed to new or improved porous membranes, separator membranes, separators, dry process separators, composites, electrochemical devices, batteries, and methods of making such membranes, separators, composites, devices, and / or batteries. According to at least certain selected embodiments, the present invention is directed to new or improved separator membranes containing additives or elastomers. The improved membranes may preferably demonstrate improved shutdown, improved strength, improved dielectric breakdown strength, and / or reduced tendency to tear.According to at least certain selected embodiments, this application or invention is directed to a battery separator having a microporous polymeric thin film or membrane and an optional coating layer on at least one side of the microporous polymeric thin film, wherein at least one of the microporous polymeric thin film and the optional coating comprises an additive. The additive may be selected from the group consisting of lubricants, plasticizers, nucleating agents, shrinkage reducing agents, surfactants, SEI modifiers, cathode protection agents, flame retardant additives, LiPF salt stabilizers, overcharge inhibitors, aluminum corrosion inhibitors, lithium deposition agents or deposition modifiers, or solvation promoters, aluminum corrosion inhibitors, wetting agents, viscosity modifiers, friction reducers, COF reducers, pin removal force reducers, copolymers, block copolymers, and / or combinations thereof. Also described herein are batteries, including lithium ion primary or secondary batteries, comprising one or more of the above-described thin films, membranes, coatings, and / or separators. Methods of making the thin films, membranes, coatings, and / or battery separators are also described. According to at least certain embodiments, this application or invention provides improved or novel battery separators having at least one of increased puncture strength, reduced pin removal force, improved electrolyte wettability, and increased pore size. the microporous polymeric thin film has an optional coating layer on at least one surface thereof; a battery separator having at least one of the optional coating and the microporous polymeric thin film therein and / or thereon; an additive selected from the group of a lubricant, a surfactant, a nucleating agent, a shrinkage reducing agent, and / or a plasticizer; a microporous polymeric thin film having an additive present primarily in at least one surface region of the film, present in a single surface region of the film, present in a first surface region of the film and a second surface region of the film opposite the first surface region, or present throughout the film; a coating applied to a surface of the microporous polymeric thin film, which coating may be applied to only one surface of the microporous polymeric thin film, or may be applied to the first surface of the microporous polymeric thin film and a separate coating may be applied to the second surface of the microporous polymeric thin film opposite the first surface region; and / or combinations thereof. According to at least some preferred embodiments, the microporous polymeric thin film or membrane is a microporous polyolefin membrane, such as a dry-stretched process membrane, such as a single-layer dry-process membrane, a two-layer dry-process membrane, or a multi-layer dry-process membrane. Also, according to at least some preferred embodiments, one, two, three, four, or all five of the different types of additives may be added, or a single additive that acts as one, two, three, four, or all five of the different types of additives may be added to the thin film, coating, or separator, such as an additive that is both a lubricant and a surfactant.

[0226] The microporous multilayer battery separators described herein, in some embodiments, exhibit improved safety, strength, and durability compared to previous bilayer, trilayer, or multilayer battery separators. For example, the separators may exhibit increased average dielectric breakdown (DB), increased minimum DB, increased shutdown speed, and increased flexure, all of which are indicative of a safer battery separator. The separators may also exhibit increased puncture strength and increased mixed penetration values, indicating stronger, more durable batteries.

[0227] These properties of the microporous multilayer battery separators described herein are at least partially a result of the method by which they are made. In some embodiments, the method includes at least coextruding two or more polymer mixtures to form a first coextruded bi-, tri-, or multi-layer film, coextruding two or more other polymer mixtures to form a second coextruded bi-, tri-, or multi-layer film, and coextruding two or more additional polymer mixtures to form a third coextruded bi-, tri-, or multi-layer film. Coextrusion typically involves using a coextrusion die with one or more extruders (typically one extruder per layer of the bi-, tri-, or multi-layer film) feeding the die. The polymer mixtures used to form each layer of the first, second, and third bi-, tri-, or multi-layer films can be the same or different. The mixtures can include one polymer or more than one polymer, e.g., polymer blends. Also, more than three bi-, tri-, or multi-layer films can be formed. After the first, second, and third bilayer, trilayer, or multilayer thin films are formed, the thin films are laminated together with two of the thin films formed on opposite sides of one of the thin films to form the microporous battery separator described herein.

[0228] The microporous multilayer battery separators described herein can be used in lithium ion batteries, including lithium secondary batteries, resulting in batteries with improved safety and durability.

[0229] The battery separators herein can be described in several different ways.

[0230] In a first aspect, a battery separator for a lithium battery is described herein. In some embodiments, the battery separator includes at least one microporous separator membrane or sub-membrane including a plurality of porous or microporous polymeric microlayers or nanolayers, wherein at least one of the individual microlayers or nanolayers includes a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to adjacent individual microlayers or nanolayers. In some embodiments, a plurality of the separator membranes or sub-membranes of polymeric microlayers or nanolayers are laminated to each other or to a microporous polymeric membrane. In some embodiments, at least one of the separator membranes or sub-membranes of polymeric microlayers or nanolayers has at least three microlayers or nanolayers. Optionally, at least one of the separator membranes or sub-membranes of polymeric microlayers or nanolayers is made of one or more polyolefins. Optionally, at least one of the separator membranes or sub-membranes of the polymeric microlayers or nanolayers is made from a coextruded dry-process polyolefin microlayer or nanolayer. In some embodiments, at least two of the separator membranes or sub-membranes of the polymeric microlayers or nanolayers. In some embodiments, at least three of the separator membranes or sub-membranes of the polymeric microlayers or nanolayers.

[0231] Described herein are multilayer microporous thin films or membranes that can exhibit improved properties, including improved dielectric breakdown and strength, compared to conventional single-layer or triple-layer microporous membranes of the same thickness. Preferred multilayer microporous membranes include a microlayer and one or more laminated barriers. Battery separators or batteries comprising one or more of the multilayer microporous thin films or membranes are also disclosed. The batteries and battery separators of the present invention are preferably safer and more robust than batteries and battery separators using conventional single-layer and triple-layer microporous membranes. Also described herein are methods for making the multilayer microporous separators, membranes, or thin films described herein.

[0232] According to at least certain embodiments, aspects, or objectives, the following may be disclosed, provided, or anticipated:

[0233] A battery separator for a lithium battery, comprising at least one microporous separator membrane or sub-membrane comprising a plurality of porous or microporous polymeric microlayers or nanolayers, wherein at least one of the individual microlayers or nanolayers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, or comprises a different or distinct additive, drug, material, and / or filler, or comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, polymer blend, additive, drug, material, and / or filler, compared to an adjacent individual microlayer or nanolayer.

[0234] The battery separator as above, wherein a plurality of the above separator membranes or sub-membranes of polymeric microlayers or nanolayers are laminated to each other or to a microporous polymer membrane.

[0235] The battery separator above, wherein at least one of said separator membranes or sub-membranes of polymeric microlayers or nanolayers has at least three microlayers or nanolayers.

[0236] At least one of said separator membranes or sub-membranes of polymeric microlayers or nanolayers The battery separator as above, which is made of one or more polyolefins.

[0237] The battery separator above, wherein at least one of said separator membranes or sub-membranes of polymeric microlayers or nanolayers is made of a coextruded dry-process polyolefin microlayer or nanolayer.

[0238] The battery separator as described above, comprising at least two of the above separator membranes or sub-membranes of polymeric microlayers or nanolayers.

[0239] The battery separator as described above, comprising at least three of the above separator membranes or sub-membranes of polymeric microlayers or nanolayers.

[0240] 10. A battery separator or separator membrane as shown or described herein.

[0241] A lithium battery containing the battery separator described above.

[0242] Improved separator, membrane or base film, wherein the separator is a multilayer separator, membrane or base film comprising one or more microporous co-extruded micro- or nano-multilayer polymeric membranes or sub-membranes adapted to be laminated or adhered to another polymeric membrane, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, comprises a different or distinct additive, drug, material, and / or filler, or comprises a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, drugs, materials, and / or fillers, compared to an adjacent individual micro- or nano-layer.

[0243] A battery separator or separator membrane comprising one or more coextruded micro-multilayer films laminated or adhered to another polymeric film, wherein the separator or separator membrane may impart improved strength, e.g., improved puncture strength, particularly at a certain thickness, and may also exhibit improved shutdown and / or reduced tear tendency, wherein at least one of the individual microlayers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, comprises a different or distinct additive, agent, material, and / or filler, or comprises a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to adjacent individual microlayers.

[0244] 1. A battery separator or separator membrane comprising one or more coextruded micro- or nano-multilayer films optionally laminated or adhered to another polymeric film, which may exhibit improved strength, improved puncture strength, and / or improved shutdown and / or reduced tear tendency, particularly at a certain thickness, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to an adjacent individual micro- or nano-layer.

[0245] A lithium battery containing the battery separator described above.

[0246] A lithium secondary battery including the battery separator.

[0247] A lithium-ion battery including the battery separator described above.

[0248] 1. An improved battery separator comprising a multilayer microporous membrane comprising 9 or more layers, wherein at least 3 consecutive layers of the microporous membrane have a thickness of 0.1 to 5 microns.

[0249] The battery separator above, wherein at least three successive layers of the microporous thin film have a thickness of 0.1 to 3 microns.

[0250] The battery separator above, wherein at least three successive layers of the microporous thin film have a thickness of 0.1 to 2.5 microns.

[0251] The battery separator above, wherein at least three successive layers of the microporous thin film have a thickness of 0.1 to 2.0 microns.

[0252] The battery separator above, wherein the multilayer microporous thin film has a thickness of 1 micron to 30 microns.

[0253] The battery separator above, wherein the multilayer microporous thin film has a thickness of 1 micron to 20 microns.

[0254] The battery separator above, wherein the multilayer microporous thin film has a thickness of 1 micron to 15 microns.

[0255] The battery separator above, wherein the multilayer microporous thin film has a thickness of 1 micron to 10 microns.

[0256] The battery separator above, wherein at least three consecutive layers are coextruded layers.

[0257] The battery separator above, wherein at least three consecutive coextruded layers are laminated together with at least one other layer to form a microporous polymeric thin film.

[0258] The battery separator above, wherein at least one other layer is a coextruded layer.

[0259] The battery separator above, wherein at least three consecutive layers comprise a polyolefin or polyolefin blend.

[0260] The battery separator above, wherein at least three successive layers each comprise polyethylene.

[0261] The battery separator above, wherein at least three successive layers each comprise polypropylene.

[0262] The battery separator above, wherein the multilayer microporous thin film comprises 12 or more layers.

[0263] The battery separator above, wherein the multilayer microporous thin film comprises 15 or more layers.

[0264] The battery separator above, wherein the multilayer microporous thin film comprises 18 or more layers.

[0265] The battery separator above, wherein the multilayer microporous thin film comprises 21 or more layers.

[0266] The battery separator above, wherein the multilayer microporous thin film comprises 24 or more layers.

[0267] The battery separator above, wherein the multilayer microporous thin film comprises 27 or more layers.

[0268] The battery separator above, wherein the multilayer microporous thin film comprises 30 or more layers. The above battery separator, wherein the multilayer microporous thin film has a puncture strength of 290 gf or more.

[0269] The above battery separator, wherein the multilayer microporous thin film has a puncture strength of 300 gf or more.

[0270] The above battery separator, wherein the multilayer microporous thin film has a puncture strength of 310 gf or more.

[0271] A battery containing one or more of the battery separators above.

[0272] 1. A method of forming an improved battery separator comprising a multilayer microporous membrane, comprising: co-extruding at least two layers; laminating at least two coextruded layers to at least one other layer to form a multilayer microporous membrane; The above method, comprising:

[0273] The above method wherein at least three layers are coextruded.

[0274] The above method wherein at least four layers are coextruded.

[0275] The above method wherein at least five layers are coextruded.

[0276] The above method wherein at least six layers are coextruded.

[0277] The above method wherein at least seven layers are coextruded.

[0278] The above method wherein at least eight layers are coextruded.

[0279] The above method wherein at least nine layers are coextruded.

[0280] The above method wherein at least 10 layers are coextruded.

[0281] The above method, wherein at least one other layer is a coextruded layer.

[0282] The above method, wherein at least one other layer is a single extruded layer.

[0283] The above method, wherein at least two coextruded layers are laminated to two other layers.

[0284] One of the other two layers is laminated to a first surface of the at least two coextruded layers, and a second of the other two layers is laminated to a surface of the at least two coextruded layers opposite the first surface. Layered, as above.

[0285] The above method, wherein at least one of the other two layers is a coextruded layer.

[0286] The above method, wherein both of the other two layers are coextruded layers.

[0287] The above method, wherein at least one of the other two layers is a coextruded layer.

[0288] The above method, wherein both of the other two layers are coextruded layers.

[0289] The above method, wherein at least one of the at least two coextruded layers, and the other layer, comprises a polyolefin or polyolefin blend.

[0290] The above method, wherein at least one of the at least two coextruded layers comprises a different polyolefin or polyolefin blend than the other layer comprises.

[0291] The above method, wherein at least one of the at least two coextruded layers comprises polypropylene and the other layer comprises polyethylene.

[0292] The above method, wherein at least one of the at least two coextruded layers comprises polyethylene and the other layer comprises polypropylene.

[0293] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0294] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0295] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0296] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0297] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0298] The above method, wherein the other two layers each comprise polypropylene or each comprise polyethylene.

[0299] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with two or more other layers.

[0300] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with three or more other layers.

[0301] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with four or more other layers.

[0302] At least one of the other two layers is a coextruded layer coextruded with five or more other layers; The above method.

[0303] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with six or more other layers.

[0304] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with seven or more other layers.

[0305] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with eight or more other layers.

[0306] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with nine or more other layers.

[0307] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with two or more other layers.

[0308] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with three or more other layers.

[0309] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with four or more other layers.

[0310] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with five or more other layers.

[0311] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with six or more other layers.

[0312] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with seven or more other layers.

[0313] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with eight or more other layers.

[0314] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with nine or more other layers.

[0315] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with two or more other layers.

[0316] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with three or more other layers.

[0317] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with four or more other layers.

[0318] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with five or more other layers.

[0319] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with six or more other layers.

[0320] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with seven or more other layers.

[0321] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with eight or more other layers.

[0322] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with nine or more other layers.

[0323] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with two or more other layers.

[0324] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with three or more other layers.

[0325] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with four or more other layers.

[0326] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with five or more other layers.

[0327] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with six or more other layers.

[0328] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with seven or more other layers.

[0329] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with eight or more other layers.

[0330] The above method, wherein at least one of the other two layers is a coextruded layer that is coextruded with nine or more other layers.

[0331] A battery separator made by the above method.

[0332] 1. A battery separator comprising a multilayer microporous thin film: a first region comprising two or more layers, the first region comprising mostly discontinuous amorphous regions when viewed in the z-direction of the thin film using an SEM; a second region including at least one layer; The battery separator as described above.

[0333] The battery separator above, wherein the second region comprises two or more layers and an amorphous region having a maximum width of 0.8 microns when viewed in the z-direction of the thin film using an SEM.

[0334] The battery separator above, wherein the maximum width of the amorphous domain is 0.7 microns.

[0335] The battery separator above, wherein the maximum width of the amorphous domain is 0.6 microns.

[0336] The battery separator above, wherein 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more of the amorphous regions in the first region are discontinuous.

[0337] The battery separator above, wherein at least one of the first and second regions comprises one or more layers comprising a polyolefin.

[0338] The above battery separator, wherein the first region comprises at least one layer comprising polyethylene and the second region comprises at least one layer comprising polypropylene.

[0339] The battery separator above, wherein at least one of the first region and the second region comprises a coextruded bilayer, trilayer, or multilayer thin film.

[0340] The battery separator above, wherein the first region comprises a coextruded bilayer, trilayer, or multilayer thin film.

[0341] The battery separator above, wherein the first region and the second region comprise a coextruded bi-layer, tri-layer, or multi-layer thin film.

[0342] The above battery separator, wherein the first region, second region, and third region of the microporous multilayer battery separator each comprise a coextruded bilayer, trilayer, or multilayer thin film.

[0343] The above battery separator, wherein at least one of the second and third regions of the microporous multilayer battery separator comprises a coextruded bilayer, trilayer, or multilayer thin film.

[0344] The battery separator above, wherein the second region comprises a coextruded bilayer, trilayer, or multilayer thin film.

[0345] The battery separator above, wherein the third region comprises a coextruded bilayer, trilayer, or multilayer thin film.

[0346] A battery separator comprising a multilayer microporous thin film having an average dielectric breakdown value (V) higher than that of a trilayer microporous thin film having the same thickness, Gurley and / or porosity as the multilayer microporous thin film.

[0347] The battery separator as described above, comprising a multilayer microporous thin film having an average dielectric breakdown value (V) that is 1 to 35% higher than that of a trilayer microporous thin film having the same thickness, Gurley and / or porosity as the multilayer microporous thin film.

[0348] The battery separator as described above, comprising a multilayer microporous thin film having an average dielectric breakdown value (V) that is 5 to 35% higher than that of a trilayer microporous thin film having the same thickness, Gurley and / or porosity as the multilayer microporous thin film.

[0349] The battery separator as described above, comprising a multilayer microporous thin film having an average dielectric breakdown value (V) that is 10 to 35% higher than that of a trilayer microporous thin film having the same thickness, Gurley and / or porosity as the multilayer microporous thin film.

[0350] The battery separator as described above, comprising a multilayer microporous thin film having an average dielectric breakdown value (V) that is 15 to 35% higher than that of a trilayer microporous thin film having the same thickness, Gurley and / or porosity as the multilayer microporous thin film.

[0351] Multilayer microporous thin films have high average breakdown values ​​(V) that are 20-35% higher than those of trilayer microporous thin films with the same thickness, Gurley, and / or porosity. The battery separator as described above, comprising a multilayer microporous thin film.

[0352] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0353] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0354] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0355] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0356] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0357] The battery separator as described above, wherein the minimum dielectric breakdown value of the multilayer microporous thin film is higher than that of a trilayer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film, e.g., 3 to 20% higher, 5 to 15% higher, or 10 to 15% higher.

[0358] The battery separator above, wherein 9 or more layers are present in the multilayer microporous thin film.

[0359] The battery separator above, wherein 9 or more layers are present in the multilayer microporous thin film.

[0360] The battery separator above, wherein 12 or more layers are present in the multilayer microporous thin film.

[0361] The battery separator above, wherein 12 or more layers are present in the multilayer microporous thin film.

[0362] The battery separator above, wherein 15 or more layers are present in the multilayer microporous thin film.

[0363] The battery separator above, wherein 15 or more layers are present in the multilayer microporous thin film.

[0364] The battery separator above, wherein 18 or more layers are present in the multilayer microporous thin film.

[0365] The battery separator above, wherein 18 or more layers are present in the multilayer microporous thin film.

[0366] The battery separator above, wherein 21 or more layers are present in the multilayer microporous thin film.

[0367] The battery separator above, wherein 21 or more layers are present in the multilayer microporous thin film.

[0368] The battery separator above, wherein 24 or more layers are present in the multilayer microporous thin film.

[0369] The battery separator above, wherein 24 or more layers are present in the multilayer microporous thin film.

[0370] The battery separator above, wherein 27 or more layers are present in the multilayer microporous thin film.

[0371] The battery separator above, wherein 27 or more layers are present in the multilayer microporous thin film.

[0372] The battery separator above, wherein 30 or more layers are present in the multilayer microporous thin film.

[0373] The battery separator above, wherein 30 or more layers are present in the multilayer microporous thin film.

[0374] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises a polyolefin.

[0375] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises a polyolefin or polyolefin blend.

[0376] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises polyethylene or a polyethylene blend.

[0377] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises polyethylene or a polyethylene blend.

[0378] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises polypropylene or a polypropylene blend.

[0379] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises polypropylene or a polypropylene blend.

[0380] The battery separator above, wherein at least one of the layers of the multilayer microporous thin film comprises polypropylene or a polypropylene blend and at least one of the layers comprises polyethylene or a polyethylene blend.

[0381] Multilayer microporous thin films: a first region comprising two or more layers, the first region comprising polypropylene and predominantly discontinuous amorphous regions when viewed in the z-direction of the thin film using an SEM; a second region including at least one layer; The battery separator as described above. Multilayer microporous thin films: a first region comprising two or more layers, the first region comprising polypropylene and predominantly discontinuous amorphous regions when viewed in the z-direction of the thin film using an SEM; a second region including at least one layer; The battery separator as described above.

[0382] Multilayer microporous thin films: a first region comprising two or more layers, the first region comprising polypropylene and predominantly discontinuous amorphous regions when viewed in the z-direction of the thin film using an SEM; a second region including at least one layer; a third region including at least one layer; The battery separator as described above. Multilayer microporous thin films: a first region comprising two or more layers, the first region comprising polypropylene and predominantly discontinuous amorphous regions when viewed in the z-direction of the thin film using an SEM; a second region including at least one layer; a third region including at least one layer; The battery separator as described above.

[0383] A battery separator comprising a multilayer microporous thin film that exhibits a peak mercury intrusion value of log differential intrusion of 5 mL / g or less when measured using mercury intrusion porosimetry.

[0384] The battery separator above, wherein the peak mercury intrusion value is 4.5 mL / g or less in log differential intrusion.

[0385] The battery separator above, wherein the peak mercury intrusion value is a log differential intrusion of 4 mL / g or less.

[0386] The battery separator above, wherein the peak mercury intrusion value is 3.5 mL / g or less in log differential intrusion.

[0387] A battery separator comprising a multilayer microporous thin film having a McMillan number greater than 5.

[0388] The battery separator as described above, having a McMillan number greater than 5.5.

[0389] The battery separator as described above, wherein the McMillan number is greater than 6.

[0390] The battery separator as described above, wherein the McMillan number is greater than 7.

[0391] The battery separator as described above, having a McMillan number greater than 7.5.

[0392] The battery separator as described above, wherein the McMillan number is greater than 8.

[0393] The battery separator as described above, wherein the McMillan number is greater than 9.

[0394] The battery separator as described above, having a McMillan number of greater than 10.

[0395] A battery separator comprising a multilayer microporous thin film having a tortuosity value of 1.6 or greater.

[0396] The above battery separator, wherein the tortuosity value is 1.7 or greater.

[0397] The battery separator above, wherein the flexural degree value is 2.0 or more.

[0398] A battery separator comprising a multilayer microporous thin film having a pin removal force of less than 50N.

[0399] The above battery separator, wherein the pin removal force is less than 40N.

[0400] The above battery separator, wherein the pin removal force is less than 30N.

[0401] The above battery separator, wherein the pin removal force is less than 20N.

[0402] The above battery separator, wherein the pin removal force is less than 15N.

[0403] The above battery separator, wherein the pin removal force is less than 10N.

[0404] a first region including two or more layers; a second region comprising two or more layers on the first surface of the first region; a third region including two or more layers on a surface of the first region opposite the first surface; 1. A battery separator comprising a multilayer microporous thin film comprising: The battery separator above, wherein at least one of the first, second, or third regions comprises PE and has a lower crystallinity than the PE-containing layer of the tri-layer microporous thin film as measured by DSC, and wherein the tri-layer microporous thin film has the same thickness as the multi-layer microporous thin film.

[0405] The above battery separator, wherein the crystallinity is 1 to 20% lower.

[0406] The battery separator as described above, wherein the crystallinity is low by 1 to 17%.

[0407] The battery separator as described above, wherein the crystallinity is low by 1 to 10%.

[0408] The battery separator as described above, wherein the crystallinity is low by 1 to 5%.

[0409] A battery separator comprising a multilayer microporous thin film comprising at least two regions or sublayers each comprising at least two microlayers, the battery separator having a mixed penetration (N) value of greater than 380N.

[0410] The above battery separator having a mixed penetration (N) value of more than 400N.

[0411] The above battery separator having a mixed penetration (N) value of greater than 450N.

[0412] The above battery separator having a mixed penetration (N) value of more than 500N.

[0413] The above battery separator having a mixed penetration (N) value of greater than 550N.

[0414] The above battery separator having a mixed penetration (N) value of more than 600N.

[0415] The above battery separator having a mixed penetration (N) value of greater than 650N.

[0416] The above battery separator having a mixed penetration (N) value of more than 700N.

[0417] A battery separator comprising a multilayer microporous thin film having an electrical resistivity of 2.0 or less.

[0418] The above battery separator, wherein the electrical resistance is 1.7 or less.

[0419] The above battery separator, wherein the electrical resistance is 1.6 or less.

[0420] The above battery separator, wherein the electrical resistance is 1.5 or less.

[0421] The above battery separator, wherein the electrical resistance is 1.4 or less.

[0422] The above battery separator, wherein the electrical resistance is 1.3 or less.

[0423] The above battery separator, wherein the electrical resistance is 1.2 or less.

[0424] The above battery separator, wherein the electrical resistance is 1.1 or less.

[0425] The above battery separator, wherein the electrical resistance is 1.0 or less.

[0426] 1. A battery separator comprising a multilayer microporous thin film comprising a region, the region comprising two or more layers, and one or more of the layers comprising polyethylene, wherein the region, when tested by the machine learning test described herein, exhibits the following: W T x'-4 or W T x'≧-2.654 is filled with the above battery separator.

[0427] below: W T x' ≥ 1.3 or W T x' ≥ 2 The above battery separator is satisfied.

[0428] 1. A battery separator comprising a multilayer microporous thin film comprising a region, the region comprising two or more layers, and one or more of the layers comprising polyethylene, wherein the region, when tested by the machine learning test described herein, exhibits the following: W T x' ≥ -5 or W T x'≧-3 is filled with the above battery separator.

[0429] below: W T x' ≥ 0 or W T x' ≥ 3 The above battery separator is satisfied.

[0430] A battery separator comprising a microporous multilayer thin film having a lower standard deviation value for dielectric breakdown than a tri-layer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film.

[0431] The above battery separator has a standard deviation value that is 10 to 60% lower.

[0432] The above battery separator has a standard deviation value that is 10 to 40% lower.

[0433] The above battery separator has a standard deviation value that is 10 to 20% lower.

[0434] 1. A battery separator having at least one multilayer microporous membrane or thin film having at least two regions or sublayers each comprising at least two microlayers, said multilayer membrane having or exhibiting at least one of the following: (a) Mixed penetration (N) values ​​greater than 380N; (b) mixed penetration (N) values ​​greater than 600N; (c) bending degree ≥ 1.8; (d) average breakdown values ​​(V) that are 1–35% higher than those of trilayer microporous thin films with the same thickness, Gurley, and / or porosity as the multilayer microporous thin films; (e) a minimum dielectric breakdown value (V) that is 3 to 20% higher than that of a trilayer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous membrane; (f) have a standard deviation value of dielectric breakdown that is 10 to 60% lower than that of a trilayer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous membrane; (g) Pass the nail penetration test; (h) having at least one microlayer comprising PO, PP and / or PE and an elastomer; (i) having at least one microlayer comprising siloxane; (j) having at least one microlayer comprising PP and an elastomer; (k) having at least one microlayer comprising a copolymer (l) having at least one microlayer comprising PP and a copolymer; (m) having at least two microlayers comprising different resins or resin blends; (n) When one of the above regions comprises polypropylene in one or more of the microlayers, when this region is tested according to the machine learning test described herein, it exhibits the following: W T x' ≥ -5 or W T x' ≥ -3; is satisfied (o) When one of the regions comprises polypropylene in one or more of the microlayers, when this region is tested according to the machine learning test described herein, it exhibits the following: W T x' ≥ 0 or W T x' ≥ 3; is satisfied (p) When one of the regions comprises polyethylene in one or more of the microlayers, when this region is tested according to the machine learning test described herein, it exhibits the following: W T x' ≥ -4 or W T x' ≥ -2.654; is satisfied (q) When one of the above regions comprises polyethylene in one or more of the microlayers, when this region is tested according to the machine learning test described herein, it exhibits the following: W T x' ≥ 1.3 or W T x' ≥ 2; is satisfied (r) When one of the above regions comprises polyethylene in one or more of the microlayers, that region, when tested according to the machine learning test described herein, exhibits the following: W T x' ≥ -4 or W T x' ≥ -2; is satisfied (s) When one of the above regions comprises polyethylene in one or more of the microlayers, that region, when tested according to the machine learning test described herein, exhibits the following: W T x' ≥ 2 or W T x' ≥ 4; is satisfied (t) one of the regions contains PE and has a crystallinity, as measured by DSC, that is 1 to 20% lower than that of a PE-containing layer of a tri-layer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multi-layer microporous thin film; (u) the microporous multilayer or thin film has 30 to 100 microlayers or more; (v) at least one of the microlayers comprises lithium stearate; (w) Multilayer microporous thin films exhibit reduced MD or TD tearing; (x) at least one of the microlayers comprises PE beads; (y) have pin removal of less than 50 N; (z) showing reduced contact with the pin; (aa) having reduced MD or TD tearing; (bb) may be a precursor for at least one of transverse direction (TD) stretching, calendaring, and pore filling The above method.

[0435] The battery separator above, wherein at least one surface of the battery separator is coated.

[0436] The battery separator above, wherein both sides of the battery separator are coated.

[0437] The battery separator above, wherein at least one surface is coated with a ceramic coating.

[0438] new or improved membranes, separator membranes, separators, battery separators, lithium secondary battery separators, multilayer membranes, multilayer separator membranes, multilayer separators, multilayer battery separators, multilayer lithium secondary battery separators, and / or multilayer battery separators, new or improved batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries having improved properties, and / or methods of making and / or using such membranes, separator membranes, separators, battery separators, lithium secondary battery separators, batteries, capacitors, fuel cells, lithium batteries, lithium ion batteries, lithium secondary batteries, and / or lithium ion secondary batteries, and / or devices, vehicles or products comprising same; new or improved membrane layers, membranes or separator films, battery separators containing such membranes, and / or related methods; new or improved porous polymeric membranes or separator membranes, battery separators containing such membranes, and / or related methods; new or improved microporous polyolefin membranes or separator membranes, microlayer membranes, multilayer membranes comprising one or more microlayer or nanolayer membranes, battery separators comprising such membranes, and / or related methods; Novel, optimized, or improved microporous stretched polymer membranes or separator membranes having one or more novel or improved outer and / or inner layers, microlayer membranes, multilayer microporous membranes or separator membranes having outer and inner layers, some of such layers or sub-layers produced by coextrusion and then laminated together to form said novel, optimized, or improved membrane or separator membrane; The layer, microlayer or nanolayer may comprise a homopolymer, copolymer, block copolymer, elastomer, and / or polymer blend; The layers, microlayers or nanolayers may comprise different or distinct polymers, homopolymers, copolymers, block copolymers, elastomers, and / or polymer blends; new or improved methods of making such membranes, separator membranes, or separators, and / or new or improved methods of using such membranes, separator membranes, or separators, for example, as lithium battery separators; new or improved multilayer and / or microlayer porous or microporous membranes, separator membranes, separators, composites, electrochemical devices, and / or batteries, and / or methods of making and / or using such membranes, separators, composites, devices, and / or batteries; A new or improved separator membrane that is multilayered, wherein one or more layers of the multilayer structure are produced in a multi-layer or micro-layer coextrusion die having multiple extruders; and / or A new or improved membrane, separator membrane, or separator that may preferably demonstrate improved shutdown, improved strength, improved dielectric breakdown strength, and / or reduced tendency to tear, as shown, described, or claimed herein.

[0439] Various embodiments of the present invention have been described in order to achieve various objects of the present invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Many changes and modifications will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention.

[0440] The present invention may be embodied without departing from its spirit and essential characteristics, and therefore, reference should be made to the appended claims, rather than the foregoing specification, as indicating the scope of the invention. Components that can be used to implement the disclosed methods and systems are disclosed. These and other components are disclosed herein, and it is understood that combinations, subsets, interactions, groups, etc. of these components are specifically contemplated and described herein for all methods and systems, even though their various individual and collective combinations and permutations may not be expressly disclosed. This applies to all aspects of this application, including, but not limited to, steps in the disclosed methods. Thus, when there are various additional steps that can be implemented, it is understood that these additional steps can each be implemented by any specific embodiment or combination of embodiments of the disclosed methods.

[0441] The above-set detailed description of structures and methods has been presented for purposes of illustration only. Examples have been used to disclose exemplary embodiments, including the best mode, and will also enable any person skilled in the art to practice the invention, including making and using any device or system, and performing any incorporated methods. These examples are not intended to be exhaustive or to limit the invention to the precise steps and / or forms disclosed, many modifications and variations are possible in light of the above teachings. Features described herein may be combined in any combination. Method steps described herein may be performed in any order that is physically possible. The patentable scope of the invention is defined by the appended claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims when they have structural elements that do not differ from the literal language of the claims, or when they include equivalent structural elements that do not differ substantially from the literal language of the claims.

[0442] The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein. Various modifications of the compositions and methods in addition to those shown and described herein are intended to be within the scope of the appended claims. Furthermore, although only certain representative compositions and method steps disclosed herein have been specifically described, other combinations of such compositions and method steps are also intended to be within the scope of the appended claims even if not specifically recited. Thus, although combinations of steps, elements, components, or components may be explicitly referred to herein or hereinafter, other combinations of steps, elements, components, or components are encompassed even if not explicitly recited.

[0443] As used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Ranges are expressed as "about" or "approximately" from one particular value, and Ranges may be expressed herein as "about" or "approximately" and / or to another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values ​​are expressed as approximations, by use of the antecedent "about," it is understood that the particular value forms another embodiment. It is further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. "Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances when the event or circumstance occurs and instances when the event or circumstance does not occur.

[0444] Throughout the detailed description and claims of this specification, the word "comprise" and variations of that word, such as "comprising" and "comprises," mean "including but not limited to" and are not intended to exclude, for example, other additives, components, integers, or steps. The terms "consisting essentially of" and "consisting of" may be used in place of "comprising" and "including" to provide more specific embodiments of the present invention, and are also disclosed. "exemplary" or "for example" means "an example of" and is not intended to convey an indication of a preferred or ideal embodiment. Similarly, "such as" is used in a descriptive or illustrative sense, rather than in a limiting sense.

[0445] Unless otherwise noted, all numbers expressing geometric shapes, dimensions, and the like used in the specification and claims should be understood to be at least as and should be construed in light of the number of significant digits and ordinary rounding approaches, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims.

[0446] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosed invention belongs. Publications and cited materials cited herein are specifically incorporated by reference.

[0447] Additionally, the invention illustratively disclosed herein may suitably be practiced in the absence of any element not specifically disclosed herein.

Claims

1. 1. A battery separator for a lithium battery comprising at least one microporous separator membrane or sub-membrane comprising a plurality of porous or microporous polymeric microlayers or nanolayers, wherein at least one of the individual microlayers or nanolayers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, a different or distinct additive, agent, material, and / or filler, or a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to an adjacent individual microlayer or nanolayer.

2. 10. The battery separator of claim 1, wherein a plurality of said separator membranes or sub-membranes of said polymeric microlayers or nanolayers are laminated to each other or to a microporous polymer membrane.

3. 10. The battery separator of claim 1, wherein at least one of said separator membranes or sub-membranes of said polymeric microlayers or nanolayers has at least three microlayers or nanolayers.

4. 10. The battery separator of claim 1, wherein at least one of the separator membranes or sub-membranes of the polymeric microlayer or nanolayer is made of one or more polyolefins.

5. 10. The battery separator of claim 1, wherein at least one of said separator membranes or sub-membranes of said polymeric microlayers or nanolayers is made of a co-extruded dry-process polyolefin microlayer or nanolayer.

6. 10. The battery separator of claim 1, comprising said separator membrane or sub-membrane of at least two of said polymeric microlayers or nanolayers.

7. 10. The battery separator of claim 1, comprising said separator membrane or sub-membrane of at least three of said polymeric microlayers or nanolayers.

8. A lithium battery comprising the battery separator of claim 1.

9. 1. An improved battery separator, membrane or base film, wherein the separator is a multilayer separator, membrane or base film comprising one or more microporous co-extruded micro- or nano-multilayer polymeric membranes or sub-membranes adapted to be laminated or adhered to another polymeric membrane, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, comprises a different or distinct additive, agent, material, and / or filler, or comprises a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to an adjacent individual micro- or nano-layer.

10. A battery separator or separator membrane comprising one or more coextruded micro-multilayer films laminated or adhered to another polymeric film, wherein the separator or separator membrane may impart improved strength, e.g., improved puncture strength, particularly at a certain thickness, and may also exhibit improved shutdown and / or reduced tear tendency, wherein at least one of the individual microlayers is made of a different or distinct polymer, polymeric material, or polymeric polymeric material compared to an adjacent individual microlayer. The battery separator or separator membrane comprises a low molecular weight polymer, a homopolymer, a copolymer, and / or a polymer blend, or comprises different or separate additives, agents, materials, and / or fillers, or comprises a combination of different or separate polymers, low molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers.

11. 1. A battery separator or separator membrane comprising one or more coextruded micro- or nano-multilayer films optionally laminated or adhered to another polymeric film, which may exhibit improved strength, improved puncture strength, and / or improved shutdown and / or reduced tear tendency, particularly at a certain thickness, wherein at least one of the individual micro- or nano-layers comprises a different or distinct polymer, molecular weight polymer, homopolymer, copolymer, and / or polymer blend, comprises a different or distinct additive, agent, material, and / or filler, or comprises a combination of different or distinct polymers, molecular weight polymers, homopolymers, copolymers, polymer blends, additives, agents, materials, and / or fillers, compared to an adjacent individual micro- or nano-layer.

12. 10. A lithium battery comprising the battery separator of claim 9.

13. A lithium battery comprising the battery separator of claim 10.

14. 12. A lithium battery comprising the battery separator of claim 11.

15. A lithium secondary battery comprising the battery separator of claim 1.

16. A lithium ion battery comprising the battery separator of claim 1.

17. 1. An improved battery separator comprising a multi-layer microporous membrane comprising nine or more layers, wherein at least three consecutive layers of said microporous membrane have a thickness of 0.1 to 5 microns.

18. 20. A battery comprising one or more of the battery separators of claim 17.

19. 1. A method for forming an improved battery separator comprising a multilayer microporous membrane, comprising: co-extruding at least two layers; laminating the at least two coextruded layers to at least one other layer to form the multilayer microporous membrane; The method comprising:

20. 20. A battery separator made by the method of claim 19.

21. 1. A battery separator comprising a multilayer microporous thin film: a first region comprising two or more layers, the first region comprising mostly discontinuous amorphous regions when viewed in the z-direction of said thin film using an SEM; a second region comprising at least one layer, the second region comprising two or more layers and an amorphous region having a maximum width of 0.8 microns when viewed in the z-direction of the thin film using an SEM; The battery separator comprising:

22. 22. The battery separator of claim 21, wherein said amorphous domains have a maximum width of 0.7 microns.

23. 22. The battery separator of claim 21, wherein said amorphous domains have a maximum width of 0.6 microns.

24. 22. The battery separator of claim 21, wherein at least 50%, at least 60%, at least 70%, at least 80%, or at least 90% of said amorphous regions in said first region are discontinuous.

25. 1. A battery separator comprising a multilayer microporous thin film, A battery separator comprising a multi-layer microporous membrane having an average dielectric breakdown value (V) higher than that of a three-layer microporous membrane having the same thickness, Gurley and / or porosity as said multi-layer microporous membrane.

26. 26. The battery separator of claim 25, comprising a multi-layer microporous membrane having an average dielectric breakdown value (V) that is 1 to 35% higher than that of a three-layer microporous membrane having the same thickness, Gurley and / or porosity as said multi-layer microporous membrane.

27. A battery separator comprising a multilayer microporous thin film that exhibits a peak mercury intrusion value of log differential intrusion of 5 mL / g or less, as measured using mercury intrusion porosimetry.

28. A battery separator comprising a multilayer microporous thin film having a McMillan number greater than 5.

29. A battery separator comprising a multilayer microporous thin film having a tortuosity value of 1.6 or greater.

30. A battery separator comprising a multilayer microporous thin film having a pin removal force of less than 50N.

31. a first region comprising two or more layers; a second region comprising two or more layers on a first surface of the first region; a third region comprising two or more layers on a surface of the first region opposite the first surface; 1. A battery separator comprising a multilayer microporous thin film comprising: the battery separator, wherein at least one of the first, second, or third regions comprises PE and has a lower crystallinity than the PE-containing layer of the tri-layer microporous thin film as measured by DSC, and the tri-layer microporous thin film has the same thickness as the multi-layer microporous thin film.

32. A battery separator comprising a multilayer microporous thin film comprising at least two regions or sub-layers each comprising at least two microlayers, the battery separator having a mixed penetration (N) value of greater than 380N.

33. 1. A battery separator comprising a multilayer microporous thin film comprising a region, the region comprising two or more layers, and one or more of the layers comprising polyethylene, wherein the region, when tested by the machine learning test described herein, exhibits the following: W Ｔ x'≧−4 or W Ｔ x'≧−2.654 wherein the battery separator is filled.

34. W Ｔ x'≧1.3 or W Ｔ x'≧2 34. The battery separator of claim 33, wherein:

35. 1. A battery separator comprising a multilayer microporous thin film comprising a region, the region comprising two or more layers, and one or more of the layers comprising polypropylene, wherein the region, when tested by the machine learning test described herein, exhibits the following: W Ｔ x'≧−5 or W Ｔ x'≧-3 wherein the battery separator is filled.

36. below: W Ｔ x' ≧ 0 or W Ｔ x′≧3 36. The battery separator of claim 35, wherein:

37. A battery separator comprising a microporous multilayer thin film having a lower standard deviation value for dielectric breakdown than a tri-layer microporous thin film having the same thickness, Gurley, and / or porosity as the multilayer microporous thin film.

38. 1. A battery separator having at least one multilayer microporous membrane or thin film having at least two regions or sublayers each comprising at least two microlayers, said multilayer membrane having or exhibiting at least one of the following: (a) Mixed penetration (N) values ​​greater than 380N; (b) a mixed penetration (N) value of greater than 600 N; (c) a degree of tortuosity of 1.8 or greater; (d) an average dielectric breakdown value (V) that is 1 to 35% higher than that of a tri-layer microporous membrane having the same thickness, Gurley, and / or porosity as said multi-layer microporous membrane; (e) a minimum dielectric breakdown value (V) that is 3 to 20% higher than that of a tri-layer microporous membrane or membrane having the same thickness, Gurley, and / or porosity as said multi-layer microporous membrane; (f) having a standard deviation value of dielectric breakdown that is 10 to 60% lower than that of a tri-layer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multi-layer microporous membrane; (g) Passes the nail penetration test; (h) having at least one microlayer comprising PO, PP and / or PE and an elastomer; (i) having at least one microlayer comprising siloxane; (j) having at least one microlayer comprising PP and an elastomer; (k) having at least one microlayer comprising copolymer (I) having at least one microlayer comprising PP and copolymer; (m) having at least two microlayers comprising different resins or resin blends; (n) when one of the regions comprises polypropylene in one or more of the microlayers, when the region is tested according to the machine learning test described herein, W Ｔ x'≧−5 or W Ｔ x′ ≥ −3; is satisfied (o) when one of the regions comprises polypropylene in one or more of the microlayers, when the region is tested according to the machine learning test described herein, W Ｔ x' ≧ 0 or W Ｔ x′≧3; is satisfied (p) when one of the regions comprises polyethylene in one or more of the microlayers, when the region is tested according to the machine learning test described herein, W Ｔ x'≧−4 or W Ｔ x' ≥ -2.654; is satisfied (q) when one of the regions comprises polyethylene in one or more of the microlayers, when that region is tested according to the machine learning test described herein, W Ｔ x'≧1.3 or W Ｔ x′≧2; is satisfied (r) when one of the regions comprises polyethylene in one or more of the microlayers, when that region is tested according to the machine learning test described herein, W Ｔ x'≧−4 or W Ｔ x′ ≥ −2; is satisfied (s) when one of the regions comprises polyethylene in one or more of the microlayers, when that region is tested according to the machine learning test described herein, W Ｔ x'≧2 or W Ｔ x′ ≥ 4; is satisfied (t) one of the regions comprises PE and has a crystallinity, as measured by DSC, that is 1 to 20% lower than that of a PE-containing layer of a tri-layer microporous membrane or thin film having the same thickness, Gurley, and / or porosity as the multi-layer microporous thin film; (u) the microporous multilayer or thin film has 30 to 100 microlayers or more; (v) at least one of said microlayers comprises lithium stearate; (w) the multilayer microporous thin film exhibits reduced MD or TD tearing; (x) at least one of said microlayers comprises PE beads; (y) having a pin removal of less than 50 N; (z) exhibits reduced contact with the pin; (aa) has reduced MD or TD splitting; (bb) may be a precursor for at least one of transverse direction (TD) stretching, calendaring, and pore filling The battery separator.

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