Improved lead-acid battery separator

Abstract

To provide an improved separator that provides improved cycle life, improved performance at partial charge, reduced water loss, and / or reduced acid depletion.SOLUTION: A lead-acid battery separator includes a porous membrane having a plurality of ribs extending from its surface. The ribs include a plurality of discontinuous peaks arranged to provide elastic support for the porous membrane to resist forces exerted by swelling NAM, thereby mitigating the effects of acid starvation associated with NAM swelling. The separator is also provided to take advantage of any motion experienced by a battery containing such a separator to facilitate acid mixing and thereby mitigate the effects of acid stratification. A lead-acid battery incorporating the separator is also provided. Such a lead-acid battery may be a flooded lead-acid battery, a reinforced flooded lead-acid battery, or may be provided to operate in a partial state of charge.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims priority to and benefit of U.S. Provisional Patent Application No. 62 / 624,278, filed January 31, 2018.

[0002] According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators for lead-acid batteries, such as flooded lead-acid batteries, and particularly reinforced flooded lead-acid batteries ("EFB"), as well as various other lead-acid batteries, such as gel and absorbent glass mat ("AGM") batteries. According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, elastomeric separators, balancing separators, EFB separators, batteries, cells, systems, methods including same, vehicles employing same, methods of manufacturing same, uses thereof, and combinations thereof. Further disclosed herein are methods, systems, and battery separators for improving battery life and reducing battery failure by reducing battery electrode acid depletion.

[0003] According to at least selected embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, reinforced flooded battery separators, batteries, cells, and / or methods of manufacturing and / or using such separators, battery separators, reinforced flooded battery separators, cells, batteries, systems, methods, and / or vehicles employing the same. According to at least certain embodiments, the present disclosure or invention is directed to new or improved battery separators, elastomeric separators, balanced separators, flooded lead-acid battery separators, or reinforced flooded lead-acid battery separators, such as those useful for deep cycling and / or partial state of charge ("PSoC") applications. Such applications may include, but are not limited to: electric machine applications, such as forklifts and golf carts (sometimes called golf cars), electric rickshaws, electric bicycles, electric tricycles, etc.; automobile or truck applications, such as starting lighting ignition (SLI) batteries, such as those used in internal combustion engine vehicles; idle-stop-start ("ISS") vehicle batteries; hybrid vehicle applications, hybrid-electric vehicle applications; batteries with high power requirements, such as uninterruptible power supply ("UPS") or valve regulated lead acid ("VRLA"), and / or batteries with high CCA requirements; inverters; and energy storage systems, such as those found in renewable and / or alternative energy systems, such as solar and wind power systems.

[0004] According to at least selected embodiments, the present disclosure or invention is directed to separators, particularly separators for flooded lead-acid batteries, capable of reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; having reduced electrical resistance and / or increasing cold cracking amps. Additionally, disclosed herein are methods, systems, and battery separators for improving battery life; reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; reducing oxidation effects; reducing water loss; reducing internal resistance; increasing wettability; improving acid diffusion; improving cold cracking amps, improving uniformity, and any combination thereof, at least in reinforced flooded lead-acid batteries. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded lead-acid batteries, including an improved novel rib design and improved separator resilience. According to at least certain embodiments, the present disclosure or invention is directed to an improved separator for reinforced flooded lead-acid batteries, including performance-enhancing additives or coatings, increased oxidation resistance, optimized porosity, increased void volume, amorphous silica, high oil absorption silica, high silanol group silica, silica with an OH to Si ratio of 21:100 to 35:100, shish-kebab structure or morphology, polyolefin microporous membranes comprising particulate fillers in an amount of 40% or more by weight of the membrane and polymer, such as ultra-high molecular weight polyethylene ("UHMWPE"), having extended chain crystals (shish formation) and folded chain crystals (kebab formation) and shish-kebab formation with an average repeat periodicity of kebab formation of 1 nm to 150 nm, reduced sheet thickness, reduced tortuosity, reduced caliper, reduced oil content, increased wettability, increased acid diffusion, and the like, and any combination thereof. [Background technology]

[0005] An exemplary lead-acid battery has a positive terminal and a negative terminal. Within the battery is an array of alternating positive (or anode) and negative (or cathode) plates, with a separator disposed between each electrode. The positive electrodes are in electrical communication with the positive terminal, and the negative electrodes are in electrical communication with the negative terminal. The positive electrodes can be doped with a positive electrode active material ("PAM"), and the negative electrodes can be doped with a negative electrode active material ("NAM"), each of which contributes to increasing the functionality of the electrode. The positive electrodes can be made essentially of lead dioxide (PbO2), and the negative electrodes can be made essentially of lead (Pb).

[0006] The anode, cathode, and separator are substantially immersed in an aqueous electrolyte solution. The electrolyte may be, for example, a solution of sulfuric acid (H2SO4) and water (H2O). The electrolyte solution may have, for example, a specific gravity of about 1.28, with a viscosity in the range of about 1.215 to 1.300.

[0007] The reaction at the lead dioxide (PbO2) anode (+) electrode (the "positive half-reaction") donates electrons and becomes positive. This positive half-reaction during charging at the lead dioxide (PbO2) anode (+) produces lead sulfate (PbSO4) and water (HO), and is shown below in Equation 1: PbO2+SO4 -2 +4H + +2e - ⇔PbSO4+2H2O (Formula 1) During the ceremony: ·PbO2 is solid lead dioxide positive (+) electrode; SO4 -2 is aqueous; 4H + is aqueous; 2e - is in a solid lead dioxide (PbO2) anode (+); ·PbSO4 is a solid precipitate in aqueous electrolytes; ·H2O is a liquid.

[0008] The positive half-reaction is reversible upon charging of the battery.

[0009] The negative half-reaction at the lead (Pb) cathode (-) electrode ("negative half-reaction") provides cations, making it negative. During discharge, the negative half-reaction produces lead sulfate (PbSO4) and anions (e - ) and is shown below in Equation 2: Pb+SO4 -2 ⇔PbSO4+2e - (Formula 2) During the ceremony: Pb is a solid lead cathode; SO4 -2 is aqueous; PbSO4 is a solid precipitate in aqueous electrolytes; and 2e - is in the lead (Pb) cathode (-) electrode; The negative half-reaction is reversible upon charging of the battery.

[0010] Taken together, these half-reactions translate into the overall chemical reaction of a lead-acid battery, as shown below in Equation 3: Pb+PbO2+2H2SO4⇔2PbSO4+2H2O (Formula 3) During the ceremony: ·Pb is a solid cathode; ·PbO2 is a solid anode (+); ·H2SO4 is a liquid in aqueous electrolyte; PbSO4 is a solid precipitate in aqueous electrolytes; and ·H2O is a liquid in aqueous electrolytes.

[0011] The overall chemical reaction is reversible upon charging the battery. For each of the above reactions, discharge moves from left to right and discharge moves from right to left. Note that other elements such as antimony (Sb) or carbon (C) may be added to the electrode plates or paste materials (PAM or NAM) to increase the efficiency of the above reactions.

[0012] As can be seen from the overall reaction, acid (H2SO4) is necessary for the electrochemical reaction and provides a medium for ions to flow between the electrodes. Therefore, it is essential that the electrodes are in constant contact with acid; otherwise, the electrodes will become acid-starved and the battery will suffer in terms of performance and lifespan.

[0013] As can be seen from Equation 2, the discharge reaction converts some of the lead (Pb) that may also be present in the NAM and the acid (H2SO4) into a larger molecule, lead sulfate (PbSO4). Because lead sulfate is a larger molecule than lead, it occupies a larger volume and is believed to contribute to NAM swelling, as discussed later in this specification. Because lead sulfate is formed during discharge, batteries operated in a partial state of charge (i.e., at least partially discharged) are more susceptible to NAM swelling.

[0014] Acid starvation has been observed to occur in the presence of NAM swelling. As the NAM swells, it compresses the cathode side of the separator and pushes the anode side toward the anode. If sufficient, this swelling can cause a portion of the separator to flex and come into contact with the anode and / or PAM. This, in turn, squeezes out any electrolyte or acid that would normally occupy the volume between the separator and the anode. The present invention addresses acid starvation as discussed in more detail herein.

[0015] Acid starvation also occurs in a condition of acid stratification, which occurs when acid, which is denser than water, settles to the bottom of the battery case and water in the electrolyte rises to the top of the case. The present invention addresses acid stratification as discussed in more detail herein.

[0016] Deep-cycle batteries, such as those used in golf carts (also known as golf cars), forklifts, electric rickshaws, electric bicycles, electric cars, hybrid vehicles, idle-stop-start ("ISS") vehicles, and stationary applications such as solar or wind power collection, operate nearly constantly in a partial state of charge. With the exception of trucks, heavy-duty ("HD") trucks, or ISS batteries, such batteries are discharged for at least 8 to 12 hours before being recharged. Furthermore, operators of these batteries must not overcharge them before recycling them for use. ISS batteries undergo discharge cycles and short intermittent charge cycles and typically rarely achieve a full charge or have been overcharged in the past. Due to their continuous use and discharge, it is essential that these batteries be able to function to their full potential during use. This is not possible if the electrodes are oxygen-starved.

[0017] In some cases, acid starvation can be at least partially avoided using valve-regulated lead-acid ("VRLA") technology, in which the acid is immobilized by either a gelled electrolyte and / or an absorbent glass mat ("AGM") battery separator system. In contrast to the free-flowing fluid electrolyte in flooded lead-acid, VRLA, and / or AGM batteries, the electrolyte is held in place by a fiber or The electrolyte is absorbed into fibrous materials such as glass fiber mats, polymer fiber mats, gelled electrolytes, etc. However, VRLA and / or AGM battery systems are substantially more expensive to manufacture than flooded battery systems. VRLA and / or AGM technology may, in some cases, be more sensitive to overcharging, dry out in high heat, lose capacity over time, and have lower specific energy. Similarly, in some cases, gelled VRLA technology may have higher internal resistance and reduced charge acceptance. Summary of the Invention [Problem to be solved by the invention]

[0018] Given the increasing use of electric vehicles, hybrid electric vehicles, ISS vehicles, and renewable and alternative energy sources to combat CO2 and other pollutant emissions, reinforced flooded lead-acid batteries are expected to become even more prevalent, and therefore batteries and separators that combat acid starvation are greatly needed.

[0019] There remains a need for improved separators that provide, at least for certain applications or batteries, improved cycle life, reduced failure, improved performance at partial states of charge, reduced water loss, and / or reduced acid depletion. More particularly, there remains a need for improved separators and improved batteries, such as those operating at partial states of charge, utilizing improved separators that provide, for example, increased battery life, reduced battery failure, improved oxidation stability, improved, maintained, and / or reduced stray current, improved end-of-charge ("EOC") current, reduced current and / or voltage required to charge and / or fully charge deep cycle batteries, minimized internal electrical resistance increase, lowered electrical resistance, reduced antimony poisoning, reduced acid stratification, reduced acid depletion, improved acid diffusion, reduced water loss, and / or improved uniformity in lead-acid batteries.

[0020] Details of one or more embodiments are set forth in the description below. Other features, objects, and advantages will be apparent from the description and claims. According to at least limited embodiments, the present disclosure or invention may address the problems or needs described above. According to at least certain embodiments, aspects, or objects, the present disclosure or invention may provide improved separators and / or batteries utilizing the separators that overcome the aforementioned problems, such as by providing batteries with reduced acid deficiency; reduced acid stratification; improved separator resilience; reduced dendrite formation; increased oxidation resistance; reduced water loss; reduced internal resistance; increased separator wettability; improved acid diffusion across the separator; improved cold cracking amps, improved uniformity; and / or improved cycling performance; and any combination thereof. [Means for solving the problem]

[0021] According to at least selected embodiments, the present disclosure or invention may address the above-mentioned problems or needs and / or provide new or improved separators and / or reinforced flooded batteries. According to at least selected embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, reinforced flooded battery separators, batteries, cells, and / or methods of making and / or using such separators, battery separators, reinforced flooded battery separators, cells, and / or batteries. According to at least certain embodiments, the present disclosure or invention is directed to new or improved battery separators, elastomeric separators, balanced separators, flooded lead-acid battery separators, or reinforced flooded battery separators for automotive applications, trucks, idle-start-stop ("ISS") batteries, batteries with high power requirements, partial-state-of-charge batteries, deep-cycle batteries such as uninterruptible power supplies ("UPS") or valve-regulated lead-acid ("VRLA") batteries, and / or batteries with high CCA requirements, and / or improved methods of making and / or using such improved separators, cells, batteries, systems, etc. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded batteries and / or improved methods of using such batteries having such improved separators. Further disclosed herein are methods, systems, and battery separators for improved battery performance and life, reduced acid stratification, reduced internal electrical resistance, increased cold cracking amps, and / or improved uniformity in at least reinforced flooded batteries. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded batteries that include or provide acid-mixed ribs or protrusions, reduced electrical resistance, performance-enhancing additives or coatings, improved fillers, increased porosity, reduced twist, reduced thickness, reduced oil content, increased wettability, increased acid diffusion, and the like.One particular, possibly preferred, new or improved separator for reinforced flooded batteries, ISS batteries, deep cycle batteries, truck batteries, heavy duty (HD) truck batteries, or partial state-of-charge batteries includes or provides acid mixing ribs, anode side serrated ribs, cathode side cross ribs ("NCR"), reduced electrical resistance, performance enhancing additives or coatings, reduced water loss, low ER, improved fillers, increased porosity, reduced twist, reduced thickness, reduced oil content, increased wettability, increased acid diffusion, etc. Another particular, possibly preferred, new or improved separator for reinforced flooded batteries, ISS batteries, deep cycle batteries, truck batteries, or partial state-of-charge batteries includes or provides acid mixing ribs, anode side serrated ribs, cathode side cross ribs, reduced electrical resistance, performance enhancing additives or coatings, reduced water loss, low ER, and / or improved fillers.

[0022] According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators for lead-acid batteries, such as flooded lead-acid batteries, and particularly reinforced flooded lead-acid batteries ("EFB"), and various other lead-acid batteries, such as gel and absorbent glass mat ("AGM") batteries. According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, elastomeric separators, balancing separators, EFB separators, batteries, cells, systems, methods including same, vehicles employing same, methods of manufacturing same, uses thereof, and combinations thereof. Further disclosed herein are methods, systems, and battery separators for improving battery life and reducing battery failure by reducing battery electrode acid depletion.

[0023] According to at least selected embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, reinforced flooded battery separators, batteries, cells, and / or methods of manufacturing and / or using such separators, battery separators, reinforced flooded battery separators, cells, batteries, systems, methods, and / or vehicles employing the same. According to at least certain embodiments, the present disclosure or invention is directed to new or improved battery separators, flooded lead-acid battery separators, or reinforced flooded lead-acid battery separators, such as those useful in deep cycling and / or partial state of charge ("PSoC") applications. Such applications may include, but are not limited to: electric machine applications, such as forklifts and golf carts (sometimes called golf cars), electric rickshaws, electric bicycles, electric tricycles, etc.; automobile or truck applications, such as start-light-ignition (SLI) batteries, such as those used in internal combustion engine vehicles; idle start-stop ("ISS") vehicle batteries; hybrid vehicle applications, hybrid-electric vehicle applications; batteries with high power requirements, such as uninterruptible power supply ("UPS") or valve regulated lead acid ("VRLA"), and / or batteries with high CCA requirements; inverters; and energy storage systems, such as those found in renewable and / or alternative energy systems, such as solar and wind power systems.

[0024] According to at least selected embodiments, the present disclosure or invention provides a separator, particularly one capable of reducing or mitigating oxygen deficiency; reducing or mitigating acid stratification; and reducing or mitigating dendritic formation. The present disclosure is directed to separators for flooded lead-acid batteries that can reduce or mitigate battery life; have reduced electrical resistance, and / or increase cold cracking amps. Additionally, disclosed herein are methods, systems, and battery separators for improving battery life; reducing or mitigating acid starvation; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; reducing oxidation effects; reducing water loss; reducing internal resistance; increasing wettability; improving acid diffusion; improving cold cracking amps, improving uniformity, and any combination thereof, in at least reinforced flooded lead-acid batteries. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded lead-acid batteries, the separator including an improved novel rib design and improved separator resilience. According to at least certain embodiments, the present disclosure or invention is directed to an improved separator for reinforced flooded lead-acid batteries, including a performance-enhancing additive or coating, increased oxidation resistance, increased porosity, increased void volume, amorphous silica, high oil absorption silica, high silanol group silica, silica with an OH to Si ratio of 21:100 to 35:100, shish-kebab structure or morphology, polyolefin microporous membranes comprising particulate fillers in an amount of 40% or more by weight of the membrane and polymer, such as ultra-high molecular weight polyethylene ("UHMWPE"), having extended chain crystals (shish formation) and folded chain crystals (kebab formation) and shish-kebab formation with an average repeat periodicity of kebab formation of 1 nm to 150 nm, reduced sheet thickness, reduced tortuosity, reduced caliper, reduced oil content, increased wettability, increased acid diffusion, and the like, and any combination thereof.

[0025] According to at least a first aspect of certain selected embodiments, a lead-acid battery separator includes a porous membrane having a polymer and a filler. The porous membrane includes at least a first surface from which at least a first plurality of ribs extend. The first plurality of ribs include a first plurality of teeth or discrete peaks or protrusions, each of which is closely spaced to provide resilience to the separator. Such resilience may refer to the separator's ability to resist deflection when under pressure due to active material swelling. Such proximity may be at least about 1.5 mm between teeth, peaks, or protrusions. The separator may further include a continuous base portion having a first plurality of teeth or discrete peaks or protrusions extending from the base portion.

[0026] In certain embodiments, the separator may include a continuous base portion having a first plurality of teeth or discrete peaks or projections extending from the base portion. The base portion may be wider than the width of the teeth or discrete peaks or projections. Additionally, the base portion may extend continuously between each of the teeth or discrete peaks or projections.

[0027] According to at least certain limited embodiments, the separator may comprise ribs that are one or more of the following: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, transverse ribs extending substantially in the widthwise direction of the separator with cracks therein or NCRs, teeth, toothed ribs, serrated, serrated ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, projections, nubs, embossments, dimples, cones, trapezoids, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, battlemented, and combinations thereof.

[0028] At least a portion of the first plurality of ribs can be defined by an angle that may be neither parallel nor perpendicular to the edge of the separator. Further, the angle can be defined as an angle relative to the longitudinal direction of the porous membrane, and the angle can be one of the following: greater than zero degrees (0°) to less than one hundred and eighty degrees (180°), greater than one hundred and eighty degrees (180°) to less than three hundred and sixty degrees (360°). In certain aspects of the disclosed embodiments, the angle can vary throughout the plurality of ribs.

[0029] In certain limited aspects of the present invention, the first plurality of ribs may have a lateral spacing pitch of about 1.5 mm to about 10 mm, and the plurality of teeth or discrete peaks or protrusions may have a longitudinal spacing pitch of about 1.5 mm to about 10 mm.

[0030] In certain limited embodiments, the separator may include a second plurality of ribs extending from the second surface of the porous membrane. The second plurality of ribs may include one or more of the following: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, cracked cross mini-ribs, and combinations thereof.

[0031] At least a portion of the second plurality of ribs can be defined by an angle that may be neither parallel nor perpendicular to the edge of the separator. Further, the angle can be defined as an angle relative to the longitudinal direction of the porous membrane, and the angle can be one of the following: greater than zero degrees (0°) to less than one hundred eighty degrees (180°), and greater than one hundred eighty degrees (180°) to less than three hundred sixty degrees (360°). In certain aspects of the disclosed embodiments, the angle can vary throughout the plurality of ribs.

[0032] The second plurality of ribs have a horizontal or vertical spacing pitch of about 1.5 mm to about 10 mm.

[0033] The first surface may include one or more ribs that are of a different height than a first plurality of ribs located adjacent the edge of the lead-acid battery separator. Similarly, the second surface may include one or more ribs that are of a different height than a second plurality of ribs located adjacent the edge of the lead-acid battery separator.

[0034] In a limited embodiment, the polymer may be one of the following: polymer, polyolefin, polyethylene, polypropylene, ultra-high molecular weight polyethylene ("UHMWPE"), phenolic resin, polyvinyl chloride ("PVC"), rubber, synthetic wood pulp ("SWP"), lignin, glass fiber, synthetic fiber, cellulosic fiber, and combinations thereof.

[0035] A fibrous mat may be provided, which may be one of: fiberglass, synthetic fiber, silica, at least one performance enhancing additive, latex, natural rubber, synthetic rubber, and combinations thereof, and may be a nonwoven, woven, mesh, fleece, net, and combinations thereof.

[0036] Additionally, the separator may be a cut piece, a leaf, a pocket, a sleeve, a wrap, an envelope, and a hybrid envelope.

[0037] In at least certain limited exemplary embodiments, the separator may include elastic means for reducing deflection of the separator.

[0038] According to at least certain limited embodiments, a lead-acid battery comprises a positive electrode and a swollen negative electrode. and a negative electrode having an active electrode material. A separator is provided such that at least a portion of the separator is disposed between the positive electrode and the negative electrode. An electrolyte is provided that substantially submerges at least a portion of the positive electrode, at least a portion of the negative electrode, and at least a portion of the separator. In at least certain limited embodiments, the separator may have a porous membrane made of at least a polymer and a filler. A first plurality of ribs may extend from a surface of the porous membrane. The ribs may be arranged to prevent acid starvation in the presence of NAM swelling, or the like. The lead-acid battery may operate under any one or more of the following conditions: during operation, stationary, for backup power applications, for cycling applications, in a partial state of charge, and any combination thereof.

[0039] The rib may include a plurality of teeth or discrete peaks or protrusions. Each tooth or discrete peak or protrusion may be spaced at least about 1.5 mm from one another within the plurality of discrete peaks. The continuous base may include a plurality of teeth or discrete peaks or protrusions extending therefrom.

[0040] The first plurality of ribs may further be provided in the battery to improve acid mixing, particularly during operation of the battery. The separator may be arranged parallel to the start and stop motion of the battery. The separator may comprise a mat adjacent to the anode, the cathode, or the separator. The mat may be at least partially made of glass fiber, synthetic fiber, silica, at least one performance-enhancing additive, latex, natural rubber, synthetic rubber, and any combination thereof. The mat may be a nonwoven fabric, a woven fabric, a mesh, a fleece, a net, and combinations thereof.

[0041] In at least certain limited embodiments of the present invention, the lead-acid battery may be a flat plate battery, a flooded lead-acid battery, an reinforced flooded lead-acid battery ("EFB"), a valve-regulated lead-acid ("VRLA") battery, a deep-cycle battery, a gel battery, an absorbent glass mat ("AGM") battery, a tubular battery, an inverter battery, a vehicle battery, a starting-lighting-ignition ("SLI") vehicle battery, an idle-start-stop ("ISS") vehicle battery, an automobile battery, a truck battery, a motorcycle battery, an all-terrain vehicle battery, a forklift battery, a golf cart battery, a hybrid-electric vehicle battery, an electric car battery, an electric rickshaw battery, or an electric bicycle battery, or any combination thereof.

[0042] In certain embodiments, the battery can operate at a depth of discharge of about 1% to about 99%.

[0043] According to at least one embodiment, a microporous separator is provided that has reduced tortuosity. Tortuosity refers to the degree of curvature / bending over its length. Thus, a microporous separator with reduced tortuosity presents a shorter path for ions to travel through the separator, thereby reducing electrical resistance. Microporous separators according to such embodiments may have reduced thickness, increased pore size, more interconnected pores, and / or more open pores.

[0044] According to at least certain selected embodiments, microporous separators with increased porosity, or separators with different pore structures and / or reduced thicknesses, whose porosity is not significantly different from that of known separators, are provided. Ions move more quickly through microporous separators with increased porosity, increased void volume, reduced tortuosity, and / or reduced thickness, thereby reducing electrical resistance. Such thickness reductions can result in a reduction in the overall weight of the battery separator, which in turn reduces the weight of the reinforced flooded battery in which the separator is used, which in turn reduces the overall weight of the vehicle in which the reinforced flooded battery is used. Such thickness reductions can alternatively result in increased space for the positive electrode active material ("PAM") or negative electrode active material ("NAM") in the reinforced flooded battery in which the separator is used.

[0045] In accordance with at least certain selected embodiments, a microporous separator is provided that has increased wettability (in water or acid) that makes the separator more accessible to electrolyte ionic species, thus facilitating their passage across the separator and reducing electrical resistance.

[0046] According to at least one embodiment, a microporous separator is provided that has a reduced final oil content. Such a microporous separator will also promote reduced ER (electrical resistance) in an enhanced flooded battery or system.

[0047] The separator may contain an improved filler that has increased friability and can increase the porosity, pore size, internal pore surface area, wettability, and / or surface area of ​​the separator. In some embodiments, the improved filler has a highly structured morphology and / or a reduced particle size and / or a different amount of silanol groups than previously known fillers, and / or is more hydroxylated than previously known fillers. The improved filler may absorb more oil and / or allow for the incorporation of a larger amount of processing oil during separator formation without simultaneously shrinking or compacting when the oil is removed after extrusion. The filler can further reduce the so-called hydrated spheres of electrolyte ions, enhancing their transport across the membrane, thereby again lowering the overall electrical resistance or ER of the battery, e.g., an enhanced flooded battery, or system.

[0048] The filler or fillers can include various species (e.g., polar species such as metals) that increase ionic diffusion and facilitate the flow of electrolyte and ions across the separator, thus leading to a decrease in overall electrical resistance when such separators are used in flooded batteries, such as enhanced flooded batteries.

[0049] The microporous separator further includes a novel and improved pore morphology and / or a novel and improved fibril morphology, so that when the separator is used in a flooded lead-acid battery, the separator contributes to significantly reducing the electrical resistance in the flooded lead-acid battery. Such an improved pore morphology and / or fibril morphology can result in a separator whose pores and / or fibrils approximate a shish kebab (or shish kebab)-type morphology. Another way to describe the novel and improved pore shape and structure is a textured fibril morphology, in which silica nodes, i.e., silica nodules, exist in a kebab-type formation on the polymer fibrils (the fibrils are sometimes called shish) within the battery separator. Furthermore, in certain embodiments, the silica structure and pore structure of the separator of the present invention can be described as a skeletal structure or a spinal column structure or a spinal cord structure, with the silica nodes on the polymer kebabs, along with the polymer fibrils, oriented substantially perpendicular to the elongated central spines or fibrils (extended chain polymer crystals) that resemble vertebrae or intervertebral discs ("kebabs"), and in some cases approximate a spine-like shape ("shishi").

[0050] In some cases, improved batteries including improved separators with improved pore and / or fibril morphology may exhibit a 20% lower electrical resistance, in some cases a 25% lower electrical resistance, in some cases a 30% lower electrical resistance, and in some cases even a drop in electrical resistance ("ER") of more than 30% (potentially reducing the battery's internal resistance), while such separators balance and maintain other important and desirable mechanical properties of lead-acid battery separators. Furthermore, in certain embodiments, the separators described herein allow more electrolyte to penetrate the pores and / or voids compared to known separators. The pores have new and / or improved hole geometries that allow for flow through or filling.

[0051] Additionally, the present disclosure provides improved reinforced flooded lead-acid batteries that include one or more improved battery separators for the reinforced flooded battery, which combine the desirable features of reduced acid stratification, reduced voltage drop (or increased voltage drop persistence), and increased CCA for the battery, in some cases greater than 8%, or greater than 9%, or in some embodiments, greater than 10%, or greater than 15%. Such improved separators can result in reinforced flooded batteries whose performance matches or even exceeds that of AGM batteries. Such low electrical resistance separators can also be processed to result in reinforced flooded lead-acid batteries with reduced water loss.

[0052] The separator may include one or more performance-enhancing additives, such as surfactants, along with other additives or agents, residual oils, and fillers. Such performance-enhancing additives can reduce separator oxidation and / or even facilitate the transport of ions across the membrane, contributing to a lower overall electrical resistance of the enhanced flooded batteries described herein.

[0053] The lead-acid battery separator described herein may include a microporous polyolefin membrane comprising a polymer, such as polyethylene, e.g., ultra-high molecular weight polyethylene, a particulate filler, and a processing plasticizer (which may optionally include one or more additional additives or agents). The microporous polyolefin membrane may comprise the particulate filler in an amount of 40% or more by weight of the membrane. The ultra-high molecular weight polyethylene may also comprise a shish-kebab morphology polymer comprising a plurality of extended chain crystals (shish formation) and a plurality of folded chain crystals (kebab formation), wherein the average repetition or periodicity of the kebab formation is 1 nm to 150 nm, preferably 10 nm to 120 nm, and more preferably 20 nm to 100 nm (at least for the rib-side portion of the separator).

[0054] The average repetition or periodicity of kebab formation is calculated according to the following definition: The surface of the polyolefin microporous membrane is observed using a scanning electron microscope ("SEM") after being subjected to metal deposition, and then an image of the surface is taken, for example, at an accelerating voltage of 1.0 kV and a magnification of 30,000 or 50,000 times. In the same visual field of the SEM image, at least three regions with continuous shish-kebab formations extending at least 0.5 μm in length are displayed. The kebab periodicity of each displayed region is then calculated. The kebab periodicity is determined by Fourier transform of the intensity profile (contrast profile) obtained by projecting the shish-kebab formation perpendicular to the shish formation in each displayed area, and the average repetition period is calculated. The images are analyzed using common analytical tools, such as MATLAB® (R2013a). The spectrum detected in the short wavelength region of the Fourier transformed spectral profile is considered noise. Such noise is mainly caused by distortion of the contrast profile. The contrast profile obtained for the separator according to the present invention appears to generate a square wave (rather than a sine wave). Furthermore, if the contrast profile is a square wave, the profile after Fourier transformation will be a sine function, and therefore, in addition to the main peak that indicates true kebab periodicity, multiple peaks will appear in the short wavelength region. Such peaks in the short wavelength region can be detected as noise.

[0055] In some embodiments, the lead-acid battery separators described herein comprise a filler selected from the group consisting of silica, precipitated silica, fumed silica, and precipitated amorphous silica; 29 The molar ratio of OH groups to Si groups in the filler, as measured by Si-NMR, is in the range of 21:100 to 35:100, in some embodiments 23:100 to 31:100, in some embodiments 25:100 to 29:100, and in certain preferred embodiments, 27:100 or greater.

[0056] The silanol groups change the silica structure from crystalline to amorphous because the relatively rigid covalent network of Si-O has partially disappeared. Amorphous-like silica, such as Si(-O-Si)2(-OH)2 and Si(-O-Si)3(-OH), has many twists, which can act as various oil absorption points. Therefore, increasing the amount of silanol groups (Si-OH) in silica increases oil absorption. Furthermore, the separators described herein, when containing silica with a higher amount of silanol groups and / or hydroxyl groups than silicas used in known lead-acid battery separators, may exhibit increased hydrophilicity and / or may have a higher void volume and / or may have certain aggregates surrounded by large voids.

[0057] The microporous separator further includes a novel and improved pore morphology and / or a novel and improved fibril morphology, so that when the separator is used in a flooded lead-acid battery, the separator contributes to significantly reducing the electrical resistance in the flooded lead-acid battery. Such an improved pore morphology and / or fibril morphology can result in a separator whose pores and / or fibrils approximate a shish kebab (or shish kebab)-type morphology. Another way to describe the novel and improved pore shape and structure is a textured fibril morphology, in which silica nodes, i.e., silica nodules, exist in a kebab-type formation on the polymer fibrils (the fibrils are sometimes called shish) within the battery separator. Furthermore, in certain embodiments, the silica structure and pore structure of the separator of the present invention can be described as a skeletal structure or a spinal column structure or a spinal cord structure, with the silica nodes on the polymer kebabs, along with the polymer fibrils, oriented substantially perpendicular to the elongated central spines or fibrils (extended chain polymer crystals) that resemble vertebrae or intervertebral discs ("kebabs"), and in some cases approximate a spine-like shape ("shishi").

[0058] In certain selected embodiments, a vehicle may include a lead-acid battery generally as described herein. The battery may further include a separator as described herein. The vehicle may be a car, truck, motorcycle, all-terrain vehicle, forklift, golf cart, hybrid vehicle, hybrid-electric vehicle battery, electric vehicle, idle-start-stop ("ISS") vehicle, electric rickshaw, electric bicycle, electric bicycle battery, and combinations thereof.

[0059] In certain preferred embodiments, the present disclosure or invention provides a flexible battery separator whose components and physical attributes and features are synergistically combined to meet or, in certain embodiments, exceed the performance of previously known flexible separators (separators having a porous membrane of a polymer, e.g., polyethylene, plus a specified amount of performance-enhancing additives and ribs), thereby unexpectedly addressing a previously unmet need in the deep-cycle battery industry. In particular, the inventive separators described herein are stronger, less brittle, less prone to breakage, and more stable (less susceptible to degradation) over time than separators traditionally used in deep-cycle batteries. The flexible, performance-enhancing additive-containing, ribbed separators of the present invention combine the desired robust physical and mechanical properties of polyethylene-based separators with the capabilities of conventional separators, while also improving the performance of battery systems employing the separators.

[0060] According to at least selected embodiments, the present disclosure or invention may address the above-mentioned problems or needs. In accordance with at least certain objectives, the present disclosure or invention may, for example, provide an enhanced flooded battery having reduced acid deficiency, reduced acid stratification, reduced dendrite growth, reduced internal electrical resistance, and increased cold cracking amps. Thus, an improved separator and / or battery can be provided that overcomes the aforementioned problems. [Brief explanation of the drawings]

[0061] [Figure 1A] FIG. 1A shows a typical lead-acid battery. [Figure 1B] FIG. 1B shows an exemplary array of alternating electrodes with battery separators interposed therebetween. [Figure 2] FIG. 2 shows a typical battery separator placed between two electrodes without any swollen active material. [Figure 3] FIG. 3 shows a typical battery separator placed between two electrodes with swollen negative electrode active material, as found in a typical lead-acid battery, especially one in a partially charged state, and especially one that is rarely overcharged. [Figure 4] FIG. 4 shows an exemplary embodiment of a battery separator of the present invention disposed between a positive electrode and a negative electrode, as found in a typical lead-acid battery; the negative electrode is shown with a swollen NAM. [Figure 5A] FIG. 5A shows an exemplary embodiment of a rib profile for an exemplary embodiment of an acid-mixing or elastomeric separator of the present invention. [Figure 5B] FIG. 5B shows an exemplary embodiment of a rib profile for an exemplary embodiment of an acid-mixing or elastomeric separator of the present invention. [Figure 5C] FIG. 5C shows an exemplary embodiment of a rib profile for an exemplary embodiment of an acid-mixing or elastomeric separator of the present invention. [Figure 5D] FIG. 5D shows an exemplary embodiment of a rib profile for an exemplary embodiment of an acid-mixing or elastomeric separator of the present invention. [Figure 6A] FIG. 6A shows the electrode surface and the part supported by the separator of the invention. [Figure 6B] FIG. 6B shows the electrode surface and the portion supported by the separator of the invention. [Figure 7A] FIG. 7A shows various exemplary negative rib configurations believed to mitigate dendrite formation and migration. [Figure 7B] FIG. 7B illustrates various exemplary negative rib configurations believed to mitigate dendrite formation and migration. [Figure 7C] FIG. 7C illustrates various exemplary negative rib configurations believed to mitigate dendrite formation and migration. [Figure 8] Figure 8 is a diagram of the test setup for mimicking NAM swelling to evaluate separator resiliency. [Figure 9] Figure 9 is a diagram of the test setup for mimicking NAM swelling to evaluate separator resiliency. [Figure 10] FIG. 10 is a photographic evaluation of separator resilience. [Figure 11] FIG. 11 is a photographic evaluation of the separator acid mixture. [Figure 12] FIG. 12 shows the particle size distribution of the new silica and the standard silica before and after 30 seconds of sonication and after 60 seconds of sonication. [Figure 13] FIG. 13 shows standard silica sizes along with silica sizes used in embodiments of the present invention. [Figure 14] Figure 14 shows the size of the new silica before and after sonication. [Figure 15] FIG. 15 shows the tip used to puncture the test separator. [Figure 16A] FIG. 16A is a schematic diagram of the extension test sample. [Figure 16B] FIG. 16B shows the sample holder for extension testing. [Figure 16C] FIG. 16C shows the sample holder for extension testing. [Figure 17A] FIG. 17A includes an SEM of the inventive separator of Example 1. [Figure 17B] FIG. 17B includes Welch power spectral density estimation graphs showing the results from FTIR spectral testing performed on the three shish kebab regions (No. 1, 2, and 3) shown and marked in FIG. 17A, where the x-axis of the graphs in FIGS. 17A-17D is normalized frequency (xπrad / sample) and the y-axis of these graphs = power / frequency (dB / rad / sample). [Figure 17C] FIG. 17C includes Welch power spectral density estimation graphs showing the results from FTIR spectral testing performed on the three shish kebab regions (No. 1, 2, and 3) shown and marked in FIG. 17A, where the x-axis of the graphs in FIGS. 17A-17D is normalized frequency (xπrad / sample) and the y-axis of these graphs = power / frequency (dB / rad / sample). [Figure 17D] FIG. 17D includes Welch power spectral density estimation graphs showing the results from FTIR spectral testing performed on the three shish kebab regions (No. 1, 2, and 3) shown and marked in FIG. 17A, where the x-axis of the graphs in FIGS. 17A-17D is normalized frequency (xπrad / sample) and the y-axis of these graphs = power / frequency (dB / rad / sample). [Figure 18A] FIG. 18A is similar to FIG. 17A, but represents an inventive separator according to Example 2. [Figure 18B] FIG. 18B is similar to FIG. 17B, but represents an inventive separator according to Example 2. [Figure 18C] FIG. 18C is similar to FIG. 17C, but represents an inventive separator according to Example 2. [Figure 18D] FIG. 18D is similar to FIG. 17D, but represents the separator of the invention of Example 2. [Figure 19A] FIG. 19A is similar to FIG. 17A, but represents an inventive separator according to Example 3. [Figure 19B] FIG. 19B is similar to FIG. 17B, but represents the separator of the invention of Example 3. [Figure 19C] FIG. 19C is similar to FIG. 17C, but represents the separator of the invention of Example 3. [Figure 19D] FIG. 19D is similar to FIG. 17D, but represents the separator of the invention of Example 3. [Figure 20A]FIG. 20A is similar to FIG. 17A, but represents the separator of the invention of Example 4. [Figure 20B] FIG. 20B is similar to FIG. 17B, but represents the separator of the invention of Example 4. [Figure 20C] FIG. 20C is similar to FIG. 17C, but represents the separator of the invention of Example 4. [Figure 20D] FIG. 20D is similar to FIG. 17D, but represents the separator of the invention of Example 4. [Figure 21A] FIG. 21A is similar to FIG. 17A, but represents the inventive separator of Example 5. [Figure 21B] FIG. 21B is similar to FIG. 17B, but represents the inventive separator of Example 5. [Figure 21C] FIG. 21C is similar to FIG. 17C, but represents the inventive separator of Example 5. [Figure 21D] FIG. 21D is similar to FIG. 17D, but represents the inventive separator of Example 5. [Figure 22A] FIG. 22A is similar to FIG. 17A, but is representative of the separator of Comparative Example 1 (CE1). [Figure 22B] FIG. 22B is similar to FIG. 17B, but is representative of the separator of Comparative Example 1 (CE1). [Figure 22C] FIG. 22C is similar to FIG. 17C, but is representative of the separator of Comparative Example 1 (CE1). [Figure 22D] FIG. 22D is similar to FIG. 17D, but is representative of the separator of Comparative Example 1 (CE1). [Figure 23A] FIG. 23A is similar to FIG. 17A, but is representative of the separator of Comparative Example 2. [Figure 23B] FIG. 23B is similar to FIG. 17B, but is representative of the separator of Comparative Example 2. [Figure 24] FIG. 24 is an SEM of the separator of Comparative Example 3. [Figure 25]FIG. 25 contains the 29Si-NMR spectra of Comparative Example 4 and Example 1, respectively. [Figure 26] FIG. 26 includes an analysis of the component peaks from the spectra of FIG. 25 to determine the Q2:Q3:Q4 ratios for the separator samples of Comparative Example 4 and Example 1, respectively. [Figure 27] FIG. 27 shows a nuclear magnetic resonance (“NMR”) tube with a separator sample immersed in D2O. [Figure 28] FIG. 28 shows the diffusion coefficients at −10° C. and Δ=20 ms for a H2SO4 only solution, a reference separator, an embodiment separator of the invention, and an AGM separator. [Figure 29] FIG. 29 shows the pore size distribution of an embodiment of the invention compared to a commercially available separator. [Figure 30] FIG. 30 shows the pore size distribution of a separator according to an embodiment of the invention. [Figure 31] FIG. 31 is a chart illustrating the dispersion of the new silica filler in a separator according to an embodiment of the invention and standard silica in a commercially available separator. [Figure 32] FIG. 32 includes a depiction of the pore size distribution of a low ER separator according to an embodiment of the present invention compared to a conventional separator. [Figure 33] Figure 33 includes a depiction of the oxidative stability of an embodiment of the present invention (sometimes referred to as an "EFS" product, Enhanced Flooded Separator™) compared to a conventional separator. In a battery overcharge test, after 1,000 hours, the separator according to the present invention is less brittle than the control separator and therefore exhibits higher elongation. [Figure 34]Figure 34 includes a depiction of electrical resistance data for separators prepared using different silica fillers. The silica fillers vary in intrinsic oil absorption. In certain embodiments of the present invention, the improved separator is formed using silica having an intrinsic oil absorption value of about 175-350 ml / 100g, in some embodiments 200-350 ml / 100g, in some embodiments 250-350 ml / 100g, and in some further embodiments 260-320 ml / 100g, although other oil absorption values ​​are possible. [Figure 35] Figure 35 contains a plot of electrical resistance data for separators prepared with different process oils, the oils having different aniline points. [Figure 36] FIG. 36 includes a plot of acid stratification (%) versus Hg porosity (%) for separators according to the present invention. [Figure 37] FIG. 37 contains a depiction of ER boil versus backweb thickness. [Figure 38] Figure 38 includes an SEM image of an embodiment of a separator of the present invention at 50,000x magnification, while Figures 39A and 39B are SEM images of the same separator at 10,000x magnification. In the SEM of Figure 38, a shish-kebab morphology or textured fibril structure is observed, with much less polymer webbing (or in some cases no polymer webbing) and much less thick fibrils or strands of hydrophobic polymer (or in some cases little or no thick fibrils or strands of hydrophobic polymer), leaving certain cavities or pores. Electrolytes and / or acids, and therefore ions, pass much more easily through the pore structure observed in this separator shown in Figures 38-39B. The separator's structure provides free space for acids to move freely. [Figure 39A] Figure 39A is an SEM image of the same separator at 10,000x magnification. [Figure 39B] Figure 39B is an SEM image of the same separator at 10,000x magnification. [Figure 40A] Figure 40A includes a depiction of the pore size distribution of separator embodiments, and Figure 40A is for a control separator. [Figure 40B] Figure 40B includes a depiction of the pore size distribution of a separator embodiment. Figure 40B is for a low ER separator with desirable mechanical properties according to one embodiment of the present invention. Note that Figure 40B can also be viewed as part of Figure 32. [Figure 41] Figure 41 includes various pore size measurements for a separator according to the present invention compared to a conventional separator. In Figure 41, the bubble flow rate difference is significant in that it measures the through-pores of the separator and their ability to functionally transport ions throughout the separator. While there is no significant difference between the average and minimum pore sizes, the maximum pore size is larger for the separator according to the present invention, and the bubble flow rate is significantly higher for the separator according to the present invention. [Figure 42A] FIG. 42A shows porometry data and depictions of liquid flow through a separator according to an embodiment of the invention (FIG. 42A) compared to liquid flow through a control separator (FIG. 42B). [Figure 42B] FIG. 42B shows porometry data and a depiction of liquid flow through a separator according to an embodiment of the invention (FIG. 42A) compared to liquid flow through a control separator (FIG. 42B). [Figure 43A] Figures 43A and 43B contain two SEMs at two different magnifications of a control separator from Daramic, LLC, in which relatively thick fibrils or strands of hydrophobic polymer are observed. [Figure 43B] Figure 43B contains two SEMs at two different magnifications of a control separator from Daramic, LLC, in which relatively thick fibrils or strands of hydrophobic polymer are observed. [Figure 44A] Figure 44A contains two SEMs at two different magnifications of another control separator from Daramic, LLC. In these SEMs, areas that appear to be polymer webbing can be observed. [Figure 44B]Figure 44B contains two SEMs at two different magnifications of another control separator from Daramic, LLC. In these SEMs, areas that appear to be polymer webbing can be observed. [Figure 45A] FIG. 45A includes an SEM of a separator formed in accordance with an embodiment of the present invention, where shish kebab polymer formation(s) is observed. [Figure 45B] Figure 45B shows how the Fourier transform contrast profile (bottom spectrum in Figure 45B) helps determine the repetition or periodicity of shish kebab formation in the separator (see shish kebab formation in the top of Figure 45B). DETAILED DESCRIPTION OF THE INVENTION

[0062] According to at least limited embodiments, the present disclosure or invention may address the above-mentioned problems or needs. According to at least certain objects, aspects, or embodiments, the present disclosure or invention may provide an improved separator and / or battery that overcomes the aforementioned problems, for example, by providing a battery with a separator that reduces acid starvation and / or mitigates the effects of acid starvation.

[0063] According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators, cells, batteries, systems, and / or methods of manufacturing and / or using such new separators, cells, and / or batteries. According to at least certain embodiments, the present disclosure or invention is directed to flat plate batteries, tubular batteries, flooded lead acid batteries, reinforced flooded lead Covered are new or improved battery separators, and / or improved methods of making and / or using such improved separators, cells, batteries, systems, etc., for acid battery cells ("EFB"), deep cycle batteries, gel batteries, absorbent glass mat ("AGM") batteries, inverter batteries, solar or wind storage batteries, vehicle batteries, start-light-ignition ("SLI") vehicle batteries, idle-start-stop ("ISS") vehicle batteries, car batteries, truck batteries, motorcycle batteries, all-terrain vehicle batteries, forklift batteries, golf cart batteries, hybrid-electric vehicle batteries, electric vehicle batteries, e-rickshaw batteries, and e-bicycle batteries. Additionally, disclosed herein are methods, systems, and battery separators for improving battery performance and life, reducing battery failure, reducing acid stratification, mitigating dendrite formation, improving oxidation stability, improving, maintaining, and / or lowering stray current, improving end-of-charge current, reducing the current and / or voltage required to charge and / or fully charge deep cycle batteries, reducing internal electrical resistance, reducing antimony poisoning, increasing wettability, improving acid diffusion, improving uniformity in lead-acid batteries, and / or improving cycling performance. According to at least certain embodiments, the present disclosure or invention is directed to improved separators, the new separators including reduced electrical resistance, performance-enhancing additives or coatings, improved fillers, increased wettability, increased acid diffusion, negative cross ribs, and the like.

[0064] As can be seen from Equation 2, the discharge reaction converts a portion of the lead (Pb) that may also be present in the NAM and the acid (H2SO4) into a larger molecule, lead sulfate (PbSO4). Because lead sulfate is a larger molecule than lead, it occupies a larger volume and is believed to contribute to NAM swelling, as discussed later in this specification. Because lead sulfate is formed during discharge, batteries operating at a partial state of charge (i.e., at least partially discharged) are more susceptible to NAM swelling. Such batteries include hybrid vehicles; hybrid-electric vehicles; idle-start-stop ("ISS") vehicles; electric vehicles such as forklifts, golf carts, electric rickshaws, electric tricycles, and electric bicycles; inverters; and those operating in renewable and / or alternative energy systems, such as solar and wind power systems. Batteries in these applications are likely to operate at a partial state of charge and may experience cathode active material swelling.

[0065] 1A, an exemplary lead-acid battery 100 includes an array 102 of alternating positive electrodes 200 and negative electrodes 201, with a separator 300 interposed between each positive electrode 200 and negative electrode 201. The electrodes 200, 201 and separator 300 are substantially immersed in a sulfuric acid (H2SO4) electrolyte 104. The positive electrode 200 is in electrical communication with a positive terminal 106, and the negative electrode 201 is in electrical communication with a negative terminal 108. Alternatively, the separator may be formed as a pocket or envelope in either the positive electrode 200 or negative electrode 201.

[0066] 2, a partial exemplary array 102 is shown looking down from the top of a battery (not shown). Separator 300 is shown having a porous membrane 302 and a series of positive ribs 304 extending therefrom that are in contact with the anode 200. Although not shown, negative mini-ribs may also be present and in contact with the cathode 201.

[0067] As the battery undergoes repeated charge and discharge cycles, the negative electrode active material ("NAM") doped into the negative electrode 201 begins to expand. While not wishing to be bound by any particular theory, it is believed that NAM swelling can occur to the extent that it exerts pressure on the separator backweb 302 to the point where the backweb 302 contacts the positive electrode 200, thus depleting the positive electrode 200 and the negative electrode 201 of electrolyte 104. This is known as acid starvation and can seriously affect the performance and / or lifespan of the battery. Acid starvation can still occur even when the backweb 302 does not contact the positive electrode 200. This is because the NAM can still swell to the point where it squeezes the electrolyte 104 out of contact with the negative electrode 201 and can further deflect the backweb 302 enough to squeeze some of the electrolyte 104 away from the positive electrode 200. FIG. 3 is a schematic representation of this effect on the separator backweb 302 up to the point where the backweb 302 contacts the anode 200.

[0068] Referring now to Figure 4, a schematic diagram of a particular exemplary separator 300 of the present invention is shown. In this example embodiment, separator 300 includes ribs 106 extending longitudinally of the separator that contact the negative electrode (i.e., negative ribs). This provides support for the NAM and spacing between the NAM and the separator backweb 302 so that the NAM does not even contact the separator backweb 302 and therefore cannot flex. It should be noted that Figures 2-4 are not drawn to scale.

[0069] As discussed herein, current separators commercially available, sold, and used in flooded lead-acid batteries, particularly enhanced flooded lead-acid batteries that operate or are intended to operate in a partial state of charge, exhibit the above-mentioned NAM swelling and acid squeezing and displacement, ultimately resulting in an inoperable battery. Accordingly, there is a need for improved separators for flooded lead-acid batteries, particularly enhanced flooded lead-acid batteries that operate in a partial state of charge (e.g., those used in start / stop vehicles).

[0070] physical properties Exemplary separators may comprise a web of porous membranes, e.g., microporous membranes having pores less than about 5 μm, preferably less than about 1 μm, mesoporous membranes, or macroporous membranes having pores greater than about 1 μm. The porous membranes may preferably have pore sizes of 1 micron or less, up to 100 μm, and in certain embodiments, from about 0.1 μm to about 10 μm. The porosity of separator membranes described herein may be greater than 50% to 60% in certain embodiments. In certain limited embodiments, the porous membrane may be flat or may have ribs extending from its surface.

[0071] rib Specific goals of the present invention include minimizing the effects of NAM swelling (e.g., acid starvation) while also taking advantage of any motion the battery may undergo to maximize acid mixing and reduce the effects of acid stratification, both of which are problems seen in batteries operated at partial states of charge.

[0072] The inventors have found that one way to minimize the effects of NAM swelling is to maximize separator resiliency, for example, by reducing the likelihood that the NAM will cause the porous backweb to flex into the positive electrode active material ("PAM"). One way to increase separator resiliency is to increase the porous membrane backweb thickness. However, this also increases the separator's electrical resistance (to name only one drawback of a thicker backweb), which negatively impacts battery performance. The inventors have found that increasing the number of contact points between the separator and the positive electrode acts to strengthen the backweb between the contact points. Achieving this goal by increasing the number of ribs also increases the amount of contact area between the separator and the positive electrode. Minimizing the contact area is believed to lower the separator's electrical resistance and also open up more of the electrode's surface area to the electrolyte for the electrochemical reactions that provide battery functionality. Reducing the contact area is also believed to reduce the chance of dendrites forming through the separator, resulting in an electrical short. The issue of dendrite formation is discussed below. A further goal is to maximize the electrolyte or acid mixture of the battery used during operation to minimize the effects of acid stratification. Furthermore, solid ribs do not facilitate the goal of acid mixture to reduce acid stratification.

[0073] The present inventors have proposed a limited preferred exemplary embodiment in which the separator and adjacent electrodes The inventors have found that the separator may be provided with elastic means to resist or mitigate deflection of the backweb under the forces and pressures exerted by NAM swelling, which leads to oxygen starvation, by maximizing the number of contact points while simultaneously minimizing the contact area between the separator and adjacent electrodes. The inventors have found that another limited exemplary embodiment can provide the separator with acid mixing means to reduce, mitigate, or reverse the effects of acid stratification by maximizing the number of discrete contact points between the separator and adjacent electrodes. Another limited exemplary embodiment can provide the separator with dendrite mitigation means to reduce or mitigate lead sulfate (PbSO4) dendrite growth. The inventors have determined that such elastic means, acid mixing means, and dendrite mitigation means can be addressed, achieved, or at least partially addressed and / or achieved by the design of the rib structure. Thus, the limited embodiments described herein rely on rib structures to balance these parameters to achieve desired goals, provide resilience means, acid mixing means, and dendrite mitigation means, and / or to at least partially address and / or achieve a balance of these parameters and / or desired resilience means, acid mixing means, and / or dendrite mitigation means.

[0074] The ribs 304, 306 may be a uniform set, alternating sets, or mix or combination of solid, discrete broken ribs, continuous, discontinuous, angled, linear, longitudinal ribs extending substantially in the machine direction ("MD") of the separator (i.e., extending from the top to the bottom of the separator in the cell), transverse ribs extending substantially in the machine direction ("MD") of the separator, transverse ribs extending substantially in the machine direction ("CMD") of the separator (i.e., transverse direction of the separator in the cell, perpendicular to the MD), cross ribs extending substantially in the machine direction ("CMD") of the separator, discrete teeth or toothed ribs, serrated, serrated ribs, battlements or battlemented ribs, curved or sinusoidal, solid or broken arranged in a zigzag-like manner, grooves, channels, textured areas, embossments, dimples, porous, non-porous, mini-ribs or cross mini-ribs, etc., and combinations thereof. Additionally, either set of ribs 304, 306 may extend from or to the anode side, cathode side, or both sides.

[0075] 5A-5D, the exemplary separator includes positive ribs 304 substantially aligned in the machine direction ("MD") of the separator that are intended to contact the positive electrode in the exemplary battery. The separator further includes negative ribs 306 that are substantially aligned in the machine direction of the separator and substantially parallel to the positive ribs. The negative ribs are intended to contact the negative electrode in the exemplary battery. The negative ribs in this illustrated example are substantially aligned in the machine direction of the separator, but may alternatively be substantially aligned in the cross direction, typically known as negative cross ribs.

[0076] Continuing with reference to Figures 5A-5D, a limited embodiment of the separator of the invention comprises an array of positive ribs. The positive ribs comprise a base portion 304a that can extend the length of the separator in the longitudinal direction. Spaced teeth, discontinuous peaks, or other protrusions 304b can thus extend from the surface of the base portion, with the teeth 304b elevated above the underlying surface of the porous membrane backweb. Furthermore, the base portion can be wider than the teeth themselves. The positive ribs extend substantially parallel to one another with a typical spacing of about 2.5 mm to about 6.0 mm, with a typical spacing of about 3.5 mm. The height of the positive ribs (tooth and base combined), measured from the surface of the porous membrane backweb, can be about 10 µm to about 2.0 mm, with a typical height of about 0.5 mm. Exemplary rib teeth of adjacent ribs can be substantially coincident with one another. However, as shown in Figures 5A-5D, exemplary teeth may be fully or partially out of phase with adjacent ribs and offset from one rib to the next. As shown, the teeth are fully out of phase from one rib to the next. The teeth on the positive ribs may be spaced apart at a pitch along the separator's length of about 3.0 mm to about 6.0 mm, with a typical spacing being about 4.5 mm.

[0077] As shown in Figures 5A-5D, the negative ribs 306 are shown as being substantially parallel to the machine direction of the separator. However, they may alternatively be substantially parallel to the cross direction. The illustrated exemplary negative ribs are shown as solid and substantially straight. However, they may alternatively be toothed in a manner generally similar to the illustrated positive ribs 304. The negative ribs 306 may be spaced apart at a pitch of about 10 µm to about 10.0 mm, with a preferred pitch being about 700 µm to about 800 µm, and a more preferred nominal pitch being about 740 µm. The height of the negative ribs, as measured from the surface of the backweb, may be about 10 µm to about 2.0 mm.

[0078] It should be noted that the positive ribs may alternatively be positioned in a typical cell so that they contact the negative electrode. Similarly, the negative ribs may alternatively be positioned in a typical cell so that they contact the positive electrode.

[0079] Table 1 below is for 162mm x 162mm (262cm 2 The figures detail the number of ribs and percentage of surface contact area for four separators (one exemplary inventive separator and three control separators). As shown, the exemplary inventive separator has 43 toothed ribs uniformly spaced laterally across the width of the separator. The teeth of the positive ribs on the exemplary inventive separator are spaced 262 cm apart on the anode. 2 The control separators are further detailed in Table 1. It is understood that control separators #1, #2, and #3 are typical of commercially available separators for flooded lead-acid batteries currently in use.

[0080] [Table 1]

[0081] As described above, the inventors have found that maximizing the number of contact points while simultaneously minimizing the contact area achieves the goal of increasing separator resilience while keeping electrical resistance under control. Furthermore, the toothed design helps promote acid mixing by taking advantage of any motion the battery may be subjected to. Referring to Figures 6A and 6B, the separator rib teeth may be spaced from the nearest adjacent tooth by about 1.5 mm to about 6.0 mm, as shown by the circles surrounding points A, B, and C. The inventors have found that a preferred, non-limiting distance between adjacent teeth is about 2.0 mm. Additionally, having teeth offset from adjacent rows that are completely out of phase also helps promote acid mixing. The inventors have also found that the base portion helps to sufficiently reinforce the backweb to provide resilience for NAM swelling.

[0082] Although the exemplary inventive ribs are shown and described herein as positive ribs 304, it is understood that they can still be provided on the cathode side of the separator, and the negative ribs 306 shown and described can be provided on the anode side of the separator.

[0083] The positive or negative ribs may further be in any form or combination of solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of said porous membrane, transverse ribs extending substantially in the widthwise direction of said porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, serrated serrated ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof.

[0084] The positive or negative ribs may also be any configuration or combination defined by an angle that is neither parallel nor perpendicular to the separator edge. Furthermore, the angle may vary across the rib tooth or row. The angled rib pattern may be a potentially preferred Daramic® RipTide™ acid-mixed rib profile, which may help reduce or eliminate acid stratification in certain batteries. Furthermore, the angle may be defined relative to the longitudinal direction of the porous membrane, and the angle may be greater than about zero degrees (0°) and less than about one hundred eighty degrees (180°), as well as greater than about one hundred eighty degrees (180°) and less than about three hundred sixty degrees (360°).

[0085] The ribs may extend uniformly across the width of the separator from edge to edge. This is known as a universal profile. Alternatively, the separator may have side panels adjacent the edge, with minor ribs disposed in the side panels. These minor ribs may be more closely spaced and smaller than the major ribs. For example, the minor ribs may be 25% to 50% the height of the major ribs. Alternatively, the side panels may be flat. The side panels may serve to seal one edge of the separator to another edge of the separator, as occurs when enclosing the separator, as described later in this specification.

[0086] In limited exemplary embodiments, at least some of the negative ribs may preferably have a height that is between about 5% and about 100% of the height of the positive ribs. In some exemplary embodiments, the negative rib height may be about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 95%, or 100% of the positive rib height. In other exemplary embodiments, the negative rib height can be about 100% or less, about 95% or less, about 90% or less, about 85% or less, about 80% or less, about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, about 50% or less, about 45% or less, about 40% or less, about 35% or less, about 30% or less, about 25% or less, about 20% or less, about 15% or less, about 10% or less, or about 5% or less compared to the positive rib height.

[0087] In some limited embodiments, at least a portion of the porous membrane may have negative ribs, which may be longitudinal, transverse, or cross ribs. The negative ribs may be parallel to the top edge of the separator or may be disposed at an angle thereto. For example, the negative ribs may be oriented at about 0°, 5°, 15°, 25°, 30°, 45°, 60°, 70°, 80°, or 90° relative to the top edge. The cross ribs may be oriented at about 0° to about 30°, about 30° to about 45°, about 45° to about 60°, about 30° to about 60°, about 30° to about 90°, or about 60° to about 90° relative to the top edge.

[0088] Certain exemplary embodiments may have a base portion. If present, the base may have an average base height of about 5 μm to about 200 μm. For example, the average base height may be about 5 μm to about 200 μm. The average base width may be about 0.0 μm or more, about 5 μm or more, about 10 μm or more, about 20 μm or more, about 30 μm or more, about 40 μm or more, about 50 μm or more, about 100 μm or more, or about 200 μm or more. Furthermore, if present, the average base width may be about 0.0 μm to about 50 μm wider than the tooth width. For example, the average base width may be about 0.0 μm or more, about 5 μm or more, about 10 μm or more, about 20 μm or more, about 30 μm or more, about 40 μm or more, or about 50 μm or more wider than the tooth width.

[0089] Certain exemplary embodiments may have teeth or tooth-like ribs. If present, they may have an average tip length of about 50 μm to about 1.0 mm. For example, the average tip length may be about 50 μm or more, about 100 μm or more, about 200 μm or more, about 300 μm or more, about 400 μm or more, about 500 μm or more, about 600 μm or more, about 700 μm or more, about 800 μm or more, about 900 μm or more, or about 1.0 mm or more. Alternatively, they may be 1.0 mm or less, 900 μm or less, 800 μm or less, 700 μm or less, 600 μm or less, 500 μm or less, 400 μm or less, 300 μm or less, 200 μm or less, 100 μm or less, or 50 μm or less.

[0090] At least some of the teeth or tooth-like ribs may have an average tooth base length of about 50 μm to about 1.0 mm. For example, the average tooth base length may be about 50 μm, about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, or about 1.0 mm. Alternatively, the average tooth base length may be about 1.0 mm or less, about 900 μm or less, about 800 μm or less, about 700 μm or less, about 600 μm or less, about 500 μm or less, about 400 μm or less, about 300 μm or less, about 200 μm or less, about 100 μm or less, or about 50 μm or less.

[0091] At least some of the teeth or tooth-like ribs may have an average height (base height and tooth height combined) of about 50 μm to about 1.0 mm. For example, the average height may be about 50 μm, about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, or about 1.0 mm. Alternatively, the average height may be about 1.0 mm or less, about 900 μm or less, about 800 μm or less, about 700 μm or less, about 600 μm or less, about 500 μm or less, about 400 μm or less, about 300 μm or less, about 200 μm or less, about 100 μm or less, or about 50 μm or less.

[0092] At least some of the teeth or tooth-like ribs may have an average center-to-center pitch within a longitudinal row of about 100 μm to about 50 mm. For example, the average center-to-center pitch may be about 50 μm or more, about 100 μm or more, about 200 μm or more, about 300 μm or more, about 400 μm or more, about 500 μm or more, about 600 μm or more, about 700 μm or more, about 800 μm or more, about 900 μm or more, or about 1.0 mm or more, in similar increments up to 50 mm. Alternatively, they may be about 50 μm or less, about 100 μm or less, about 200 μm or less, about 300 μm or less, about 400 μm or less, about 500 μm or less, about 600 μm or less, about 700 μm or less, about 800 μm or less, about 900 μm or less, or about 1.0 mm or less, in similar increments up to 50 mm. Additionally, adjacent rows of teeth or toothed ribs may be similarly positioned at the same longitudinal location, i.e., offset. In an offset configuration, adjacent teeth or toothed ribs are positioned at different longitudinal locations.

[0093] At least a portion of the teeth or tooth-like ribs may have an average height-to-base width ratio of about 0.1:1.0 to about 500:1.0. For example, the average height-to-base width ratio may be about 0.1:1.0, about 25:1.0, about 50:1.0, about 100:1.0, about 150:1.0, about 200:1.0, about 250:1.0, about 300:1.0, about 350:1.0, about 450:1.0, or about 500:1.0. Alternatively, the average height-to-base width ratio may be about 500:1.0 or less, about 450:1.0 or less, about 400:1.0 or less, about 350:1.0 or less, about 300:1.0 or less, about 250:1.0 or less, about 200:1.0 or less, about 150:1.0 or less, It may be about 100:1.0 or less, about 50:1.0 or less, about 25:1.0 or less, or about 0.1:1.0 or less.

[0094] At least a portion of the teeth or toothed ribs can have an average base width to tip width ratio of about 1,000:1.0 to about 0.1:1.0. For example, the average base width to tip width ratio can be about 0.1:1.0, about 1.0:1.0, about 2:1.0, about 3:1.0, about 4:1.0, about 5:1.0, about 6:1.0, about 7:1.0, about 8:1.0, about 9:1.0, about 10:1.0, about 15:1.0, about 20:1.0, about 25:1.0, about 50:1.0, about 100:1.0, about 150:1.0, about It may be 200:1.0, about 250:1.0, 300:1.0, about 350:1.0, about 450:1.0, about 500:1.0, about 550:1.0, about 600:1.0, about 650:1.0, about 700:1.0, about 750:1.0, about 800:1.0, about 850:1.0, about 900:1.0, about 950:1.0, or about 1,000:1.0. Alternatively, the average base width to tip width ratio is about 1,000:1.0 or less, about 950:1.0 or less, about 900:1.0 or less, about 850:1.0 or less, about 800:1.0 or less, about 750:1.0 or less, about 700:1.0 or less, about 650:1.0 or less, about 600:1.0 or less, about 550:1.0 or less, about 500:1.0 or less, about 450:1.0 or less, about 400:1.0 or less, about 350:1.0 or less, about 300:1.0 or less, about 250: 1.0 or less, about 200:1.0 or less, about 150:1.0 or less, about 100:1.0 or less, about 50:1.0 or less, about 25:1.0 or less, about 20:1.0 or less, about 15:1.0 or less, about 10:1.0 or less, about 9:1.0 or less, about 8:1.0 or less, about 7:1.0 or less, about 6:1.0 or less, about 5:1.0 or less, about 4:1.0 or less, about 3:1.0 or less, about 2:1.0 or less, about 1.0:1.0 or less, or about 0.1:1.0 or less.

[0095] Figures 7A-7C illustrate various scenarios for dendrite formation. The figures show various embodiments of a separator 300 positioned between an anode 200 and a cathode 201. While all separators have positive ribs 304, only Figures 7B and 7C show a separator 300 with a cathode 306. The inventors believe that the more contact the separator 300 has with the cathode 201, the more likely dendrites 400 will form and grow within its porous structure. As shown in Figure 7A, the backweb 302 has a flat surface facing the cathode 201. According to the inventors' hypothesis, dendrites 400 have more opportunities to grow and form bridges between the cathode 201 and anode 200 within the separator 300. FIG. 7B shows a separator 300 with negative cross ribs 306, thus reducing the contact area between the separator 300 and the cathode 201 and reducing the opportunity for dendrites 400 to form and grow within the separator 300 and bridge between the two electrodes 200, 201. As shown in FIG. 7C, the separator 300 has fewer negative cross ribs 306 than shown in FIG. 7B, which are also more widely spaced and taller than those shown in FIG. 7B. In this way, there is even less contact between the separator 300 and the cathode 201, and therefore even less opportunity for dendrites 400 to bridge from the cathode 201 and anode 200. We hypothesize that reducing contact between the ribs 306 and the cathode 201, for example by providing discontinuous or broken ribs in some manner, may further reduce the opportunity for dendrite 400 growth. This can be achieved by providing discontinuous, broken, serrated, or other shaped ribs where there are portions of the rib 306 that do not contact the surface of the cathode 201. While these examples focus on the negative ribs 306, the same treatment may be applied to the positive ribs 304.

[0096] Separator testing 8 and 9, a clamp test fixture for compression testing to simulate NAM swelling to evaluate separator resiliency is shown. As shown, the structure is made of the following components: 1) a foam backing with a solid backing to simulate NAM swelling or expansion; 2) a negative rib on the foam backing; and 3) a solid plastic plate in contact with the positive rib and coated with red paint. Compression tests were performed as follows: 1) Cut or otherwise form the separator, two solid plastic plates, and foam backing all into 5-inch (12.7 cm) by 5-inch (12.7 cm) square pieces; 2) Forming a paint applicator as follows: a) Tape the felt sheet to the plastic square; b) Using a 3 mL dropper, mix 9 mL of red paint with 3 mL of water in a rectangular dish; and c) Place the paint applicator, felt side down, in the dish and leave it there until application; 3) Mark all pieces with arrows to ensure all parts are added in the same order and in the same direction. Provide the stacking cell in the following order from bottom to top: a) a first solid plastic plate (where the paint is applied); b) a separator (having positive ribs in contact with a first solid plastic plate); c) a foam backing approximately 7.6 mm thick; and d) a second solid plastic plate; 4) applying appropriate air pressure to apply the desired pressure to the foam backing while applying test pressures of about 11 kPa, about 16.5 kPa, about 22 kPa, and about 27.5 kPa to the stack to simulate NAM swelling; 5) applying paint to a first solid plastic piece by placing the first solid plastic piece on a firm, solid surface facing upward; removing the paint applicator from the paint and dragging it across the top of the pan to remove some of the paint; placing the paint applicator on the top surface of the solid plastic piece and moving it across the plastic in a first direction parallel to the surface of the first solid plastic piece, then moving the paint applicator in a second direction perpendicular to the first direction; all the while ensuring that the coating of paint is uniform and has as few air bubbles as possible; 6) Add the separator with the positive rib in contact with the coating surface and the remaining parts in the above order, and place them in a compression device before the coating material is substantially dry; 7) Engage the clamping device to clamp the stack to the desired pressure and hold the stack in the clamped position for one minute; 8) Release the compression and remove the stack from the device; remove the separator from the first solid plastic piece and leave it to dry; 9) Wipe any remaining paint off the first plastic piece with water and a paper towel for the next test; and 10) Measure the thickness of the foam backing after each test to ensure that the foam backing is still intact; replace the foam if it does not return to its original thickness after repeated use.

[0097] As shown in Figure 9, pressure was applied uniformly to the stack. Specifically, pressures of 11 kPa, 16.5 kPa, 22 kPa, and 27.5 kPa were applied in different tests on a given separator sample. In this test, the separator ribs contacted the solid plate with the red paint in the structure (i.e., before pressure was applied to the structure), which inevitably resulted in red paint adhering to the rib tips. However, transfer of red paint to the separator backweb indicated that the backweb had deformed toward the solid plate coated with red paint. The results of this compression test are detailed in Table 2 and photographed in Figure 42. It is understood that the photograph is of a representative portion of the separator, not the entire separator.

[0098] Referring to Table 2 below, the performance in the presence of NAM swelling (i.e., acid availability) is shown for one exemplary inventive separator sample and three control separator samples. The separator samples are the same as those previously shown in Table 1. It is understood that a new separator sample was used for each test at various pressures. All separators are made with the same composition of polyethylene, silica, and residual unextracted oil. Additionally, all separators have an average backweb thickness of approximately 250 μm and a total thickness ranging from approximately 800 μm to approximately 1.0 mm.

[0099] [Table 2]

[0100] The photographic results, shown in Figure 10, reveal that at all applied pressures, 0% of the red paint was transferred to the backweb surface of the inventive separator samples, with paint transferred only to the rib tips. At an applied pressure of 11 kPa, red paint was transferred to 0% of the backweb surface of control separator #1, approximately 20% of the backweb surface of control separator #2, and 50% of the backweb surface of control separator #3.

[0101] These test results show that acid availability under compression is not affected when using a separator according to the present invention. The same is shown for Control Separator #1 under low pressure. However, acid availability under compression is affected when using Control Separators #2 and #3. The control separator samples are generally representative of typical separators currently on the market for flooded lead-acid batteries that operate or are intended to operate at a partial state of charge.

[0102] To determine the effectiveness of the inventive separator in minimizing the effects of acid stratification, the separator was subjected to a motion test. For this test, a structure was assembled containing a foam backing with separators formed on both sides of the foam backing. Foam was placed on the cathode side (opposite the ribs) of both separators to simulate cathode active material swelling. The structure was then placed in a motion device. Sulfuric acid and water were added to the device. Adding methyl orange to the sulfuric acid resulted in acid red and clear water on top, creating a stratified cell. The acid had a specific gravity of 1.28. The structure was subjected to 0, 30, and 60 motions to simulate the motion of a start / stop car. Figure 11 shows photographic evidence of this motion test for an inventive separator sample and a control separator #3 sample. As shown, acid remained available to the inventive separator throughout these motions while mixing. For control separator #3, most of the acid was displaced and squeezed out from between the ribs, and no acid mixing was observed.

[0103] Backweb Thickness In some embodiments, the porous separator membrane can have a backweb thickness of about 50 μm to about 1.0 mm. For example, the backweb thickness can be about 50 μm, about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, or about 1.0 mm. In other exemplary embodiments, the backweb thickness T BACK can be about 1.0 mm or less, about 900 μm or less, about 800 μm or less, about 700 μm or less, about 600 μm or less, about 500 μm or less, about 400 μm or less, about 300 μm or less, about 200 μm or less, about 100 μm or less, or about 50 μm or less. In certain embodiments, very thin flat backweb thicknesses of 50 μm or less are provided, for example, thicknesses of about 10 μm to about 50 μm.

[0104] The total thickness of exemplary separators (backweb 302 thickness and positive rib 304 and negative rib 306 height) typically ranges from about 250 μm to about 4.0 mm. Separators used in automotive start / stop batteries typically range from about 250 μm to about 1.0 mm. Separators used in industrial traction start / stop batteries typically range from about 1.0 mm to about 4.0 mm.

[0105] Form / Envelope The separator 300 can be provided as a flat sheet, one or more leaves, a wrap, a sleeve, or an envelope or pocket separator. An exemplary envelope separator may enclose the anode (a "positive-enveloping separator"), thus having two inner surfaces facing the anode and two outer surfaces facing the adjacent cathode. Alternatively, another exemplary envelope separator may enclose the cathode (a "negative-enveloping separator"), thus having two inner surfaces facing the cathode and two outer surfaces facing the adjacent anode. In such an enclosed separator, the bottom edge 103 may be a folded or sealed crease edge. Furthermore, the side edges 105a, 105b may be continuously or intermittently sealed seam edges. The edges may be bonded or sealed by adhesive, heat, ultrasonic welding, etc., or any combination thereof.

[0106] Certain exemplary separators can be processed to form hybrid envelopes. Hybrid envelopes can be provided by folding a separator sheet in half and forming one or more slits or openings before, during, or after bonding the edges of the separator sheet together to form the envelope. The length of the openings can be at least 1 / 50, 1 / 25, 1 / 20, 1 / 15, 1 / 10, 1 / 8, 1 / 5, 1 / 4, 1 / 3, or 1 / 2 of the overall edge length. The length of the openings can be 1 / 50 to 1 / 3, 1 / 25 to 1 / 3, 1 / 20 to 1 / 3, 1 / 20 to 1 / 4, 1 / 15 to 1 / 4, 1 / 15 to 1 / 5, or 1 / 10 to 1 / 5 of the overall edge length. Hybrid envelopes can have 1 to 5, 1 to 4, 2 to 4, 2 to 3, or 2 openings, which may or may not be evenly spaced along the length of the bottom edge. Preferably, the corners of the envelope are free of openings. The slits may be cut after the separator is folded and sealed to obtain the envelope, or the slits may be formed before the porous membrane is formed into the envelope.

[0107] Some other exemplary embodiments of separator assembly configurations include: anode-facing ribs 104; cathode-facing ribs 104; cathode or anode envelope; cathode or anode sleeve, cathode or anode hybrid envelope; both electrodes may be surrounded or sleeved, and any combination thereof.

[0108] composition In certain embodiments, the improved separator may include a porous membrane that may be made from: a natural or synthetic substrate; a processed plasticizer; a filler; a natural or synthetic rubber(s) or latex, and one or more other additives and / or coatings.

[0109] Base material In certain embodiments, exemplary natural or synthetic substrates may include: polymers; thermoplastic polymers; phenolic resins; natural or synthetic rubbers; synthetic wood pulp; lignin; glass fibers; synthetic fibers; cellulosic fibers; and any combination thereof. In certain preferred embodiments, the exemplary separator may be a porous membrane made from a thermoplastic polymer. Exemplary thermoplastic polymers may include, in principle, any acid-resistant thermoplastic material suitable for use in lead-acid batteries. In certain preferred embodiments, exemplary thermoplastic polymers may include polyvinyls and polyolefins. In certain embodiments, polyvinyls may include, for example, polyvinyl chloride ("PVC"). In certain preferred embodiments, polyolefins may include, for example, polyethylene, polypropylene, ethylene-butene copolymers, and any combination thereof, preferably polyethylene. In certain embodiments, exemplary natural or synthetic rubbers may include, for example, latex, uncrosslinked or crosslinked rubber, crumb rubber, or ground rubber, and any combination thereof.

[0110] Additionally, it has been observed that NAM swelling is reduced when antimony (Sb) is present in the NAM and / or the cathode. Therefore, there may be an antimony coating on the separator or an antimony additive in the separator composition.

[0111] Polyolefin In certain embodiments, the porous membrane layer preferably comprises a polyolefin, particularly polyethylene. Preferably, the polyethylene is a high molecular weight polyethylene ("HMWPE") (e.g., a polyethylene having a molecular weight of at least 600,000). Even more preferably, the polyethylene is an ultra-high molecular weight polyethylene ("UHMWPE"). Exemplary UHMWPE may have a molecular weight of at least 1,000,000, particularly greater than 4,000,000, and most preferably 5,000,000 to 8,000,000, as measured by viscometry and calculated according to the Margolie equation. Furthermore, exemplary UHMWPE may have a standard load melt index of substantially zero (0), as measured as specified in ASTM D1238 (Condition E) using a 2,160 g standard load. Additionally, the exemplary UHMWPE may have a viscosity number, measured in a solution of 0.02 g of polyolefin in 100 g of decalin at 130° C., of 600 ml / g or greater, preferably 1,000 ml / g or greater, more preferably 2,000 ml / g or greater, and most preferably 3,000 ml / g or greater.

[0112] rubber The novel separators disclosed herein may comprise latex and / or rubber. As used herein, rubber refers to rubber, latex, natural rubber, synthetic rubber, crosslinked or uncrosslinked rubber, cured or uncured rubber, crumb rubber, or ground rubber, or mixtures thereof. Exemplary natural rubbers may include one or more blends of polyisoprene, commercially available from various suppliers. Exemplary synthetic rubbers include methyl rubber, polybutadiene, chloroprene rubber, butyl rubber, bromobutyl rubber, polyurethane rubber, epichlorohydrin rubber, polysulfide rubber, chlorosulfonyl polyethylene, polynorbornene rubber, acrylate rubber, fluororubber, and silicone rubber, and copolymer rubbers, such as styrene / butadiene rubber, acrylonitrile / butadiene rubber, ethylene / propylene rubber ("EPM" and "EPDM"), and ethylene / vinyl acetate rubber. The rubber may be crosslinked or uncrosslinked; in certain preferred embodiments, the rubber is uncrosslinked. In certain embodiments, the rubber may be a blend of crosslinked and uncrosslinked rubber.

[0113] plasticizer In certain embodiments, exemplary processing plasticizers may include processing oils, petroleum oils, paraffinic mineral oils, mineral oils, and any combination thereof.

[0114] Filler The separator may include a filler having a high structural morphology. Exemplary fillers may include silica, dry micronized silica; precipitated silica; amorphous silica; highly brittle silica; alumina; talc; fish meal; fish bone meal; carbon; carbon black, and the like, and combinations thereof. In certain preferred embodiments, the filler is one or more silicas. High structural morphology refers to an increased surface area. The filler may have a surface area of, for example, about 100 m 2 / g, about 110m 2 / g, about 120m 2 / g, about 130m 2 / g, about 140m 2 / g, about 150m 2 / g, about 160m 2 / g, about 170m 2 / g, about 180m 2 / g, about 190m 2 / g, about 200m 2 / g, about 210m 2 / g, about 220m 2 / g, about 230m 2 / g, about 240m 2 / g or about 250m 2 In some embodiments, the filler (e.g., silica) may have a high surface area of ​​greater than about 100 m / g. 2 / g~about 300m 2 / g, approx. 125m 2 / g ~ approx. 275m 2 / g, approx. 150m 2 / g ~ approx. 250m 2 / g, or preferably about 170m 2 / g ~ approx. 220m 2 The surface area can be evaluated using a TriStar 3000™ for multi-point BET nitrogen surface area. High structural morphology allows the filler to retain more oil during the manufacturing process. For example, a filler with high structural morphology has a high level of oil absorption, for example, greater than about 150 ml / 100 g, greater than about 175 ml / 100 g, greater than about 200 ml / 100 g, greater than about 225 ml / 100 g, greater than about 250 ml / 100 g, greater than about 275 ml / 100 g, greater than about 300 ml / 100 g, greater than about 325 ml / 100 g, or greater than about 350 ml / 100 g. In some embodiments, the filler (e.g., silica) may have an oil absorption of 200-500 ml / 100 g, 200-400 ml / 100 g, 225-375 ml / 100 g, 225-350 ml / 100 g, or 225-325 ml / 100 g, preferably 250-300 ml / 100 g. In some cases, a silica filler with an oil absorption of 266 ml / 100 g is used. Such a silica filler has a moisture content of 5.1%, a water content of 178 m 2 / g BET surface area, an average particle size of 23 μm, a 230 mesh sieve retention value of 0.1%, and a bulk density of 135 g / L.

[0115] Silica, which has a relatively high level of oil absorption and a relatively high level of affinity for a plasticizer (e.g., mineral oil), is desirably dispersible in a mixture of polyolefin (e.g., polyethylene) and plasticizer when forming exemplary lead-acid battery separators of the type shown herein. In the past, when large amounts of silica were used to make such separators or membranes, some separators suffered from poor dispersibility due to silica agglomeration. In at least some of the inventive separators shown and described herein, the polyolefin, e.g., polyethylene, forms a shish-kebab structure because there are few silica aggregates or agglomerates to inhibit the molecular motion of the polyolefin upon cooling of the molten polyolefin. This all contributes to improved ionic permeability through the resulting separator membrane, and the formation of the shish-kebab structure or morphology means that mechanical strength is maintained or even improved while producing a lower overall ER separator.

[0116] In some limited embodiments, the filler (e.g., silica) has an average particle size of 25 μm or less, and in some cases, 22 μm or less, 20 μm or less, 18 μm or less, 15 μm or less, or 10 μm or less. In some cases, the average particle size of the filler particles is 15-25 μm. The particle size and / or surface area of ​​the silica filler contribute to the oil absorption of the silica filler. The silica particles in the final product, i.e., separator, may fall within the aforementioned size ranges. However, the initial silica used as a raw material may be obtained as one or more agglomerates and / or aggregates and may have a size of about 200 μm or more.

[0117] In some preferred embodiments, the silica used to make the inventive separator has an increased amount or number of surface silanol groups (surface hydroxyl groups) compared to silica fillers previously used to make lead-acid battery separators, e.g. Silica fillers that may be used in certain preferred embodiments herein may be silica fillers that have at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, or at least 35% more silanol and / or hydroxyl surface groups compared to known silica fillers used to make known polyolefin lead-acid battery separators.

[0118] The ratio (Si-OH) / Si relative to elemental silicon (Si) can be measured, for example, as follows.

[0119] 1. Freeze-pulverize a polyolefin porous membrane (certain inventive membranes containing certain various oil-absorbing silicas according to the present invention) and analyze it using solid-state nuclear magnetic resonance spectroscopy ( 29 Prepare powder-like samples for Si-NMR.

[0120] 2. For powder-like samples 29 Si-NMR was performed to observe the spectrum containing Si spectral intensity directly bonded to the hydroxyl group (spectrum: Q2 and Q3) and Si spectral intensity directly bonded only to the oxygen atom (spectrum: Q4). The molecular structure of each NMR peak spectrum can be expressed as follows: Q2: (SiO)2-Si*-(OH)2: has two hydroxyl groups Q3: (SiO)3-Si*-(OH): has one hydroxyl group Q4: (SiO)4-Si*: All Si bonds are SiO Here, Si* is an element that has been verified by NMR observation.

[0121] 3. The conditions for 29Si-NMR used for observation are as follows: ·Equipment: Bruker BioSpin Avance500 ·Resonance frequency: 99.36MHz Sample size: 250mg ·NMR tube: 7mφ Observation method: DD / MAS Pulse width: 45° Repeat time: 100 seconds Scans: 800 Magic angle rotation: 5,000Hz Chemical shift reference: -22.43 ppm silicone rubber

[0122] 4. The spectral peaks are numerically separated, and the area ratio of each peak belonging to Q2, Q3, and Q4 is calculated. Then, based on this ratio, the molar ratio of hydroxyl groups (-OH) directly bonded to Si is calculated. The conditions for numerical peak separation are as follows: Fitting range: -80 to -130 ppm · Initial peak top: -93 ppm for Q2, -101 ppm for Q3, and -111 ppm for Q4, respectively. Initial full width at half maximum: 400Hz for Q2, 350Hz for Q3, and 450Hz for Q4, respectively. Gaussian function ratio: 80% initially, 70-100% during fitting.

[0123] 5. Calculate the peak area ratios of Q2, Q3, and Q4 (total is 100) based on each peak obtained by fitting. The NMR peak area corresponds to the number of molecules of each silicate bond structure (thus, in the Q4 NMR peak, four Si-O-Si bonds exist in the silicate structure; in the Q3 NMR peak, three Si-O-Si bonds exist in the silicate structure, while one Si-OH bond exists; in the Q2 NMR peak, two Si-O-Si bonds exist in the silicate structure, while two Si-OH bonds exist). Therefore, multiply the number of hydroxyl groups (-OH) in Q2, Q3, and Q4 by 2, 1, and 0, respectively. Add up these three results. The sum represents the molar ratio of hydroxyl groups (-OH) directly bonded to Si.

[0124] In certain embodiments, the silica is 29The molar ratio of OH groups to Si groups, as measured by Si-NMR, may be in the range of about 21:100 to 35:100, in some preferred embodiments about 23:100 to about 31:100, in certain preferred embodiments about 25:100 to about 29:100, and in other preferred embodiments at least about 27:100 or more.

[0125] In some limited embodiments, the use of the aforementioned fillers allows for the use of a higher proportion of processing oil during the extrusion step. The porous structure in the separator is formed, in part, by the removal of oil after extrusion; therefore, the greater the amount of oil initially absorbed, the higher the porosity or void volume. While an essential component of the extrusion step, oil is a non-conductive component of the separator. Residual oil in the separator protects the separator from oxidation if it comes into contact with the anode. The production of conventional separators allows for the precise amount of oil used in the processing step to be controlled. Generally speaking, conventional separators are produced using 50-70% processing oil, in some embodiments, 55-65%, in some embodiments, 60-65%, and in some embodiments, about 62% by weight of processing oil. Reducing the oil content below about 59% has been known to result in burning due to increased friction against the extruder components. However, increasing the oil content significantly above the specified amount can result in shrinkage during the drying stage and dimensional instability. While previous attempts to increase the oil content have resulted in pore shrinkage or condensation upon oil removal, separators prepared as disclosed herein exhibit minimal, if any, shrinkage and condensation upon oil removal. Thus, porosity can be increased without sacrificing pore size and dimensional stability, thereby decreasing electrical resistance.

[0126] In certain limited embodiments, the use of the fillers described above allows for a reduction in the final oil concentration in the final separator. Because oil is a non-conductor, reducing the oil content can increase the ionic conductivity of the separator, which can help reduce the separator's ER. Thus, separators with reduced final oil content can have increased efficiency. In certain limited embodiments, separators are provided that have a final processing oil content (by weight) of less than 20%, e.g., about 14% to 20%, and in some specific embodiments, less than 19%, less than 18%, less than 17%, less than 16%, less than 15%, less than 14%, less than 13%, less than 12%, less than 11%, less than 10%, less than 9%, less than 8%, less than 7%, less than 6%, or less than 5%.

[0127] The filler can further reduce the so-called hydrated spheres of electrolyte ions and enhance their transport across the membrane, thereby again lowering the overall electrical resistance or ER of the battery, e.g., enhanced flooded battery, or system.

[0128] The filler or fillers can include various species (e.g., polar species such as metals) that facilitate the flow of electrolyte and ions across the separator, thus leading to a decrease in overall electrical resistance when such separators are used in flooded batteries, such as reinforced flooded batteries.

[0129] friability In certain limited embodiments, the filler can be alumina, talc, silica, or a combination thereof. In some embodiments, the filler can be precipitated silica, and in some embodiments, the precipitated silica is amorphous silica. In some embodiments, it is preferred to use aggregates and / or agglomerates of silica or friable silica that allow for fine dispersion of the filler throughout the separator, thereby reducing tortuosity and electrical resistance. In certain preferred embodiments, the filler (e.g., silica) is characterized by a high level of friability. Good friability enhances dispersion of the filler throughout the polymer during extrusion of the porous membrane, enhancing porosity and thus overall ionic conductivity through the separator.

[0130] Friability can be measured as the ability, tendency, or propensity of silica particles or materials (aggregates or agglomerates) to break down into smaller, more dispersible particles, pieces, or components. As shown on the left side of Figure 12, virgin silica is more friable (broken down into smaller pieces by 30 and 60 seconds of sonication) than standard silica. For example, virgin silica had a 50% volume particle size of 24.90 μm at 0 seconds of sonication, 5.17 μm at 30 seconds, and 0.49 μm at 60 seconds. Thus, 30 seconds of sonication resulted in a greater than 50% size (diameter) reduction, and 60 seconds resulted in a greater than 75% size (diameter) reduction of 50% volume silica particles. Therefore, one possible preferred definition of "high friability" could be a 30-second sonication with at least a 50% average size (diameter) reduction, and a 60-second sonication with silica particles (or when processing a resin-silica mixture to form a membrane) with at least a 75% average size (diameter) reduction. In at least certain embodiments, it may be preferable to use a more friable silica, and even more preferable to use a silica that is friable and whose friability is multimodal, e.g., bimodal or trimodal. Referring to Figure 12, the standard silica appears monomodal in its friability or particle size distribution, while the new silica appears more friable, bimodal (two peaks) at 30 seconds of sonication and trimodal (three peaks) at 60 seconds of sonication. One or more such friability and multimodal particle sizes may provide enhanced membrane and separator properties. Figure 12 is an SEM image comparing the standard silica and the new silica. Figure 14 is an SEM image of the new silica before and after sonication.

[0131] The use of a filler having one or more of the above properties allows for the production of a separator with a higher final porosity. The separators disclosed herein can have a final porosity of greater than 60%, greater than 61%, greater than 62%, greater than 63%, greater than 64%, greater than 65%, greater than 66%, greater than 67%, greater than 68%, greater than 69%, or greater than 70%. Porosity can be measured using a gas adsorption method. Porosity can be measured according to BS-TE-2060.

[0132] In some limited embodiments, the porous separator can have a higher proportion of larger pores while maintaining an average pore size of about 1 μm or less, about 0.9 μm or less, about 0.8 μm or less, about 0.7 μm or less, about 0.6 μm or less, about 0.5 μm or less, or about 0.1 μm or less.

[0133] According to at least one embodiment, the separator is made from polyethylene, such as ultra-high molecular weight polyethylene ("UHMWPE"), mixed with processing oil and fillers, and any desired additives. According to at least one other embodiment, the separator is comprised of ultra-high molecular weight polyethylene (UHMWPE) mixed with processing oil and talc. According to at least one other embodiment, the separator is comprised of UHMWPE mixed with processing oil and silica, e.g., precipitated silica, e.g., amorphous precipitated silica. The additives can then be applied to the separator by one or more of the techniques described above.

[0134] In addition to reducing electrical resistance and increasing cold cracking amps, the preferred separator is also designed to provide other benefits. With respect to assembly, the separator passes through processing equipment more easily and is therefore manufactured more efficiently. For high speed assembly and to prevent short circuits later in life, the separator has a higher tensile strength compared to standard PE separators. Combined with reduced electrical resistance and increased cold cracking amps, battery manufacturers are likely to see improved and sustained electrical performance in their batteries with these new separators.

[0135] Electrical resistance In certain selected embodiments, the disclosed separators have reduced electrical resistance, for example, less than about 200 mΩ·cm. 2 Below, approximately 180mΩcm 2 Below, approximately 160mΩcm 2 Below, approximately 140mΩ·cm 2 Below, approximately 120mΩ·cm 2 Below, approximately 100 mΩ cm 2 Below, approximately 80 mΩ cm 2 Below, approximately 60mΩ·cm 2 Below, approximately 50 mΩ cm 2 Below, approximately 40 mΩ cm 2 Below, approximately 30 mΩ cm 2 or less, or approximately 20 mΩ·cm 2 In various embodiments, the separators described herein exhibit an ER reduction of about 20% or more compared to known separators of the same thickness. For example, known separators have an ER of 60 mΩ cm. 2 Therefore, a separator according to the present invention at the same thickness would have an ER value of about 48 mΩ·cm 2 has an ER value of less than

[0136] To test a sample separator for ER test evaluation according to the present invention, the sample separator must first be prepared. To do so, the sample separator is submerged in a bath of, preferably, demineralized water, and the water is then brought to a boil. The separator is then removed after 10 minutes in the boiling saltwater bath. After removal, excess water is shaken off the separator, and it is then placed in a sulfuric acid bath with a specific gravity of 1.280 at 27°C ± 1°C. The separator is left to soak in the sulfuric acid bath for 20 minutes. The separator is then ready to be tested for electrical resistance.

[0137] Puncture resistance In certain selected embodiments, exemplary separators may be characterized by increased puncture resistance, such as about 9 N or greater, 9.5 N or greater, 10 N or greater, 10.5 N or greater, 11 N or greater, 11.5 N or greater, 12 N or greater, 12.5 N or greater, 13 N or greater, 13.5 N or greater, 14 N or greater, 14.5 N or greater, 15 N or greater, 15.5 N or greater, 16 N or greater, 16.5 N or greater, 17 N or greater, 17.5 N or greater, 18 N or greater, 18.5 N or greater, 19 N or greater, 19.5 N or greater, or 20 N or greater. In certain embodiments, exemplary separators may be specified with a puncture resistance of about 9 N to 20 N or greater, or more preferably about 12 N to 20 N or greater.

[0138] Puncture resistance can be measured as the force required to puncture a porous membrane using a tip 500, generally as illustrated in FIG. 25. The puncture base on which the porous membrane is supported while the tip 500 punctures the membrane can generally be described as a base with linear holes 6.5 mm in diameter and 10 mm deep. The tip's travel limit can be approximately 4 mm to 8 mm below the puncture base surface. The puncture tip 100 moves linearly into the membrane at a speed of approximately 5 mm / s.

[0139] Oxidative stability In certain limited embodiments, exemplary separators can be characterized by improved and higher oxidation resistance. Oxidation resistance is measured by the lateral elongation of sample separator specimens after extended exposure to lead-acid battery electrolyte. For example, exemplary separators can have an elongation at 40 hours of about 150% or more, about 200% or more, about 250% or more, about 300% or more, 350% or more, 400% or more, 450% or more, or 500% or more. In certain embodiments, exemplary separators can have favorable oxidation resistance, i.e., an elongation at 40 hours of about 200% or more.

[0140] To test the sample for oxidation resistance, a sample specimen 600 of the exemplary separator is first cut into the shape generally shown in Figure 16A. The specimen 600 is then placed into a sample holder 650, generally shown in Figures 16B and 16C.

[0141] The first set of samples is tested for percentage elongation to break in a dry state at time=0 (0). Elongation is based on a distance of 50 mm measured from points A and B in Figure 16A. For example, if points A and B are elongated to a distance of 300%, the final distance between A and B will be 150 mm.

[0142] The elongation test is designed to simulate, in a short period of time, the prolonged exposure to electrolyte in a cycling battery. The sample 600 is first completely submerged in isopropanol, drained, and then submerged in water for 1-2 seconds. The sample is then submerged in the electrolyte solution. The solution is prepared by sequentially adding 360 ml of 1.28 specific gravity sulfuric acid, 35 ml of 1.84 specific gravity sulfuric acid, and 105 ml of 35% hydrogen peroxide. The solution is maintained at 80°C, and the sample is submerged in the solution for an extended period of time. The sample can be tested for elongation at regular intervals, such as 20 hours, 40 hours, 60 hours, and 80 hours. To test at these intervals, the sample 600 is removed from the 80°C electrolyte bath and placed under lukewarm running water until the acid is removed. The elongation can then be tested.

[0143] According to at least limited embodiments, the present disclosure or invention is directed to improved battery separators, low ER or high conductance separators, improved lead-acid batteries, e.g., flooded lead-acid batteries, high conductance batteries, and / or improved vehicles including such batteries, and / or methods of making or using such separators or batteries, and / or combinations thereof. According to at least certain embodiments, the present disclosure or invention is directed to improved lead-acid batteries incorporating improved separators, the improved lead-acid batteries exhibiting increased conductance.

[0144] Additives / Surfactants In certain embodiments, exemplary separators may include one or more performance-enhancing additives added to the separator or porous membrane. The performance-enhancing additives may be surfactants, wetting agents, colorants, antistatic additives, antimony suppression additives, UV protection additives, antioxidants, and the like, and any combination thereof. In certain embodiments, the additional surfactant may be an ionic, cationic, anionic, or nonionic surfactant.

[0145] In certain embodiments described herein, reduced amounts of anionic or nonionic surfactants are added to the porous membranes or separators of the invention. Due to the lower amount of surfactant, desirable characteristics may include lower total organic carbon ("TOC") and / or lower volatile organic compounds ("VOCs").

[0146] Certain suitable surfactants are nonionic, while other suitable surfactants are anionic. The additive may be a single surfactant or a mixture of two or more surfactants, such as two or more anionic surfactants, two or more nonionic surfactants, or at least one ionic surfactant and at least one nonionic surfactant. Certain suitable surfactants may have an HLB value of less than 6, preferably less than 3. The use of these certain suitable surfactants in combination with the inventive separators described herein can result in even further improved separators that, when used in lead-acid batteries, provide the lead-acid batteries with reduced water loss, reduced antimony poisoning, improved cycling, reduced floating current, reduced floating potential, or the like, or any combination thereof. Suitable surfactants include surfactants such as alkyl sulfates; alkylaryl sulfonates; alkylphenol-alkylene oxide adducts; soaps; alkyl-naphthalene-sulfonates; one or more sulfo-succinates, such as anionic sulfo-succinates; dialkyl esters of sulfo-succinates; amino compounds (primary, secondary, tertiary, or quaternary amines); ethylene oxide and propylene glycol mono- and di-methyl-2 ... These include block copolymers of polyethylene oxides, various polyethylene oxides, and salts of mono- and di-alkyl phosphate esters. Additives may include nonionic surfactants such as polyol fatty acid esters, polyethoxylated esters, polyethoxylated alcohols, alkyl polysaccharides such as alkyl polyglycosides and blends thereof, amine ethoxylates, sorbitan fatty acid ester ethoxylates, organosilicone surfactants, ethylene vinyl acetate terpolymers, ethoxylated alkylaryl phosphate esters, and sucrose esters of fatty acids.

[0147] In certain embodiments, the additive can be represented by a compound of formula (I): R(OR 1 ) n (COOM x+ 1 / x ) m (I) During the ceremony: R is a linear or non-aromatic hydrocarbon radical having 10 to 4200 carbon atoms, preferably 13 to 4200 carbon atoms, optionally interrupted by oxygen atoms; ·R 1 =H, -(CH2)COOM x+ 1 / x or -(CH2) k -SO3M x+ 1 / x, preferably H, where k=1 or 2; M is an alkali metal or alkaline earth metal ion, H+ or NH4+, where not all of the variables M simultaneously represent H+; n=0 or 1; m = 0 or an integer between 10 and 1400; and x=1 or 2.

[0148] The ratio of oxygen atoms to carbon atoms in the compounds according to formula (I) ranges from 1:1.5 to 1:30, and m and n cannot simultaneously be 0. However, preferably, only one of the variables n and m is not 0.

[0149] A non-aromatic hydrocarbon radical refers to a radical that does not contain an aromatic group or that represents a radical by itself, and the hydrocarbon radical may be interrupted by an oxygen atom (i.e., it may contain one or more ether groups).

[0150] R is preferably a linear or branched aliphatic hydrocarbon radical, optionally interrupted by an oxygen atom. Saturated unbridged hydrocarbon radicals are particularly preferred. However, as noted above, R may, in certain embodiments, contain an aromatic ring.

[0151] The use of compounds of formula (I) to prepare battery separators can effectively protect them from oxidative breakdown.

[0152] Preferred is a battery separator comprising a compound according to formula (I), wherein: R is a hydrocarbon radical having 10 to 180, preferably 12 to 75, particularly preferably 14 to 40 carbon atoms, which may be interrupted by 1 to 60, preferably 1 to 20, particularly preferably 1 to 8 oxygen atoms, particularly preferably of the formula R 2 -[(OC2H4)p(OC3H6) q ]-, a hydrocarbon radical of the formula: 〇R 2 is an alkyl radical having 10 to 30 carbon atoms, preferably 12 to 25, particularly preferably 14 to 20 carbon atoms, and R 2 may be linear or non-linear, such as containing aromatic rings; 〇P is an integer of 0 to 30, preferably 0 to 10, particularly preferably 0 to 4; and q is an integer of 0 to 30, preferably 0 to 10, particularly preferably 0 to 4; Particularly preferred are compounds in which the sum of p and q is 0 to 10, in particular 0 to 4; n=1; and ·m=0.

[0153] formula R 2It should be understood that -[(OC2H4)p(OC3H6)q]- also includes compounds other than those indicated by the sequence of radicals in the brackets. For example, compounds formed by alternating radicals in the brackets, (OC2H4) and (OC3H6), are preferred according to the invention.

[0154] R 2 However, additives which are linear or branched alkyl radicals having 10 to 20, preferably 14 to 18, carbon atoms have proven particularly advantageous. OC2H4 preferably represents OCH2CH2 and OC3H6 represents OCH(CH3)2 and / or OCH2CH2CH3.

[0155] Preferred additives include, in particular, alcohols (p=q=0; m=0), with primary alcohols being particularly preferred, fatty alcohol ethoxylates (p=1-4, q=0), fatty alcohol propoxylates (p=0; q=1-4) and fatty alcohol alkoxylates (p=1-2; q=1-4), with primary alcohol ethoxylates being preferred. Fatty alcohol alkoxylates are obtainable, for example, from the reaction of the corresponding alcohol with ethylene oxide or propylene oxide.

[0156] Additives of type m=0, which are insoluble or sparingly soluble in water and sulfuric acid, have proven particularly beneficial.

[0157] Also preferred are additives comprising a compound according to formula (I), wherein: R is an alkane radical having 20 to 4200, preferably 50 to 750, particularly preferably 80 to 225, carbon atoms; M is an alkali metal or alkaline earth metal ion, H + or NH4 + , especially alkali metal ions, e.g., Li + , Na + and K. + or H + and all variables M are simultaneously H + does not mean; ·n=0; m is an integer between 10 and 1400; and x=1 or 2.

[0158] Salt Additives In certain embodiments, suitable additives include polyacrylic acid, polymethacrylic acid, and acrylic acid-methacrylic acid copolymers, in particular, whose acid groups are at least partially neutralized, preferably 40%, particularly preferably 80%. The percentage refers to the number of acid groups. Particularly preferred is poly(meth)acrylic acid, which exists entirely in the form of a salt. Suitable salts include Li, Na, K, Rb, Be, Mg, Ca, Sr, Zn, and ammonium (NR4, where R is either hydrogen or a carbon functional group). Poly(meth)acrylic acids include polyacrylic acid, polymethacrylic acid, and acrylic acid-methacrylic acid copolymers. The average molar mass M is 1,000 to 100,000 g / mol, particularly preferably 1,000 to 15,000 g / mol, and very particularly preferably 1,000 to 4,000 g / mol. w The molecular weight of poly(meth)acrylic acid polymers and copolymers is determined by measuring the viscosity (Fikentscher constant) of a 1% aqueous solution of the polymer neutralized with sodium hydroxide solution.

[0159] Copolymers of (meth)acrylic acid are also suitable, in particular copolymers which, in addition to (meth)acrylic acid, contain ethylene, maleic acid, methyl acrylate, ethyl acrylate, butyl acrylate and / or ethylhexyl acrylate as comonomers. Copolymers containing at least 40% by weight, preferably at least 80% by weight, of (meth)acrylic acid monomers are also suitable. Polymers are preferred; percentages are based on the acid form of the monomer or polymer.

[0160] Alkali metal and alkaline earth metal hydroxides, such as potassium hydroxide and especially sodium hydroxide, are particularly suitable for neutralizing polyacrylic acid polymers and copolymers. Additionally, coatings and / or additives for enhancing the separator may include, for example, metal alkoxides, where the metal may be, by way of example (but not by way of limitation), Zn, Na, or Al, and, by way of example, sodium ethoxide.

[0161] In some embodiments, the porous polyolefin membrane may include a coating on one or both sides of such layer. Such coatings may include surfactants or other materials. In some embodiments, the coating may include one or more materials described, for example, in U.S. Patent No. 9,876,209, incorporated herein by reference. Such coatings can, for example, reduce the overcharge voltage of the battery system, thereby extending battery life with less grid corrosion and preventing drying out and / or water loss.

[0162] ratio In certain limited embodiments, the membrane can be prepared by combining, by weight, about 5-15% polymer, optionally about 10% polymer (e.g., polyethylene), about 10-75% filler (e.g., silica), optionally about 30% filler, and about 10-85% processing oil, optionally about 60% processing oil. In other embodiments, the filler content is reduced and the oil content is higher, e.g., greater than about 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, or 70% by weight. The filler:polymer ratio (by weight) can be approximately (or can be approximately within these specified ranges) 2:1, 2.5:1, 3:1, 3.5:1, 4.0:1, 4.5:1, 5.0:1, 5.5:1, or 6:1, etc. The filler:polymer ratio (by weight) can be from about 1.5:1 to about 6:1, in some cases from 2:1 to 6:1, from about 2:1 to 5:1, from about 2:1 to 4:1, and in some cases from about 2:1 to about 3:1. The amounts of filler, oil, and polymer are all balanced for runnability and desired separator properties, such as electrical resistivity, basis weight, puncture resistance, bending stiffness, oxidation resistance, porosity, physical strength, torsion, and the like.

[0163] According to at least one embodiment, the porous membrane can include UHMWPE blended with processing oil and precipitated silica. According to at least one embodiment, the porous membrane can include UHMWPE blended with processing oil and precipitated silica. The blend can also include small amounts of other additives or agents common in separator technology (e.g., surfactants, wetting agents, colorants, antistatic additives, antioxidants, etc., and any combination thereof). In one particular example, the porous polymer layer can be a homogeneous blend of 8-100% by volume polyolefin, 0-40% by volume plasticizer, and 0-92% by volume inert filler material. A preferred plasticizer is petroleum. Plasticizers are useful for imparting porosity to battery separators because they are easily removed from polymer-filler-plasticizer compositions by solvent extraction and drying.

[0164] In certain embodiments, the porous membranes disclosed herein may comprise latex and / or rubber, which may be natural rubber, synthetic rubber, or a mixture thereof. Natural rubber may include one or more blends of polyisoprene, commercially available from various suppliers. Exemplary synthetic rubbers include methyl rubber, polybutadiene, chloroprene rubber, butyl rubber, bromobutyl rubber, polyurethane rubber, epichlorohydrin rubber, polysulfide rubber, chlorosulfonyl polyethylene, polynorbornene rubber, acrylate rubber, fluororubber, and silicone rubber, and copolymer rubbers, such as styrene / butadiene rubber, acrylonitrile / butadiene rubber, ethylene / propylene rubber (EPM and EPDM), and ethylene / vinyl acetate rubber. The rubber may be crosslinked or uncrosslinked; in certain preferred embodiments, the rubber is uncrosslinked. In certain embodiments, the rubber may be a blend of crosslinked and uncrosslinked rubber. The rubber can be present in the separator in an amount that is at least about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10% by weight based on the final separator weight (weight of the polyolefin separator sheet or layer containing the rubber and / or latex). In certain embodiments, the rubber can be present in an amount of about 1-6%, about 3-6%, about 3%, and about 6% by weight. The porous membrane can have a filler to polymer and rubber (filler:polymer and rubber) weight ratio of about 2.6:1.0. The amounts of rubber, filler, oil, and polymer are all balanced for feasibility and desired separator properties, such as electrical resistance, basis weight, puncture resistance, bending stiffness, oxidation resistance, porosity, physical strength, torsion, etc.

[0165] Porous membranes made according to the present invention, including polyethylene and a filler (e.g., silica), typically have a residual oil content; in some embodiments, such residual oil content is about 0.5% to about 40% of the total weight of the separator membrane (sometimes about 10-40% of the total weight of the separator membrane, sometimes about 20-40% of the total weight). In certain limited embodiments herein, some to all of the residual oil in the separator may be replaced by adding more performance-enhancing additives, such as surfactants, for example, surfactants with a hydrophilic-lipophilic balance ("HLB") of less than 6, or, for example, nonionic surfactants. For example, the performance-enhancing additives, such as surfactants, for example, nonionic surfactants, may constitute from 0.5% to the entire amount of the residual oil (e.g., 20%, or 30%, or even 40%) of the total weight of the porous separator membrane, thereby partially or completely replacing the residual oil in the separator membrane.

[0166] manufacturing In some embodiments, exemplary porous membranes can be produced by mixing the components in an extruder. For example, about 30% by weight of filler, about 10% by weight of UHMWPE, and about 60% processing oil can be mixed in the extruder. Exemplary porous membranes can be produced by passing the components through a heated extruder and passing the extrudate produced by the extruder through a die and a nip formed by two heated press or calender stacks or rolls to form a continuous web. A substantial amount of the processing oil can be extracted from the web using a solvent, which can then be removed by drying. The web can then be cut into lanes of a predetermined width and then wound into a roll. Furthermore, various groove patterns can be cut into the press or calender roll to provide ribs, grooves, textured areas, embossments, etc., substantially as described herein.

[0167] Rubber manufacturing In some embodiments, exemplary porous membranes can be made by mixing components in an extruder. For example, about 5-15% by weight of polymer (e.g., polyethylene), about 10-75% by weight of filler (e.g., silica), about 1-50% by weight of rubber and / or latex, and about 10-85% by weight of processing oil can be mixed in the extruder. Exemplary porous membranes can be made by passing the components through a heated extruder and passing the extrudate produced by the extruder through a die and a nip formed by two heated press or calender stacks or rolls to form a continuous web. A substantial amount of the processing oil can be extracted from the web by using a solvent. The web can then be dried, slit into lanes of a predetermined width, and then wound into a roll. Additionally, the press or calender roll can be cut with various groove patterns to provide ribs, grooves, textured areas, embossments, etc., substantially as described herein. The amounts of rubber, filler, oil, and polymer are all balanced for feasibility and desired separator properties, such as electrical resistance, basis weight, puncture resistance, bending stiffness, oxidation resistance, porosity, physical strength, torsion, and the like.

[0168] In addition to adding rubber to the extruder components, certain embodiments incorporate the rubber into the porous membrane after extrusion. For example, the rubber may be coated on one or both sides, preferably the side facing the cathode, with a liquid slurry containing rubber and / or latex, optionally silica, and water, which is then dried to form a film of this material on the surface of the exemplary porous membrane. For better wetting of this layer, known wetting agents can be added to the slurry for use in lead-acid batteries. In certain embodiments, the slurry may also contain one or more performance-enhancing additives, such as those described herein. After drying, a porous layer and / or film is formed on the surface of the separator, which adheres very well to the porous membrane and increases electrical resistance very little, if at all. After the rubber is added, further compression can be performed using either a machine press or a calender stack or rolls. Another possible method for applying the rubber and / or latex is to dip coat, roller coat, spray coat, or curtain coat one or more surfaces of the separator with the rubber and / or latex slurry, or any combination thereof. These processes can occur before or after the processing oil is extracted, or before or after scoring into lanes.

[0169] A further embodiment of the present invention involves depositing the rubber onto the membrane by impregnation and drying.

[0170] Manufactured with performance-enhancing additives In certain embodiments, performance enhancing additives or agents (e.g., surfactants, wetting agents, colorants, antistatic additives, antioxidants, etc., and any combination thereof) may also be mixed together with other components in the extruder. A porous membrane according to the present disclosure can then be extruded into a sheet or web shape and finished in substantially the same manner as described above.

[0171] In certain embodiments, in addition to or instead of being added to the extruder, one or more additives can be applied, for example, to the separator porous membrane during finishing (e.g., after the majority of the processing oil has been extracted and before or after the rubber is introduced). According to certain preferred embodiments, the additive or a solution of the additive (e.g., an aqueous solution) is applied to one or more surfaces of the separator. This variant is particularly suitable for applying non-heat-resistant additives and additives that are stable in the solvent used for processing oil extraction. Particularly suitable solvents for the additives according to the invention are low-molecular-weight alcohols, such as methanol and ethanol, as well as mixtures of these alcohols with water. Application can be carried out on the side of the separator facing the cathode, the side facing the anode, or both. Application can also be carried out during extraction of the pore-forming agent (e.g., processing oil) in a solvent bath. In certain limited embodiments, some portion of the performance-enhancing additive, for example, a surfactant coating or performance-enhancing additive (or both) added to the extruder before the separator is made, can combine with antimony in the battery system to deactivate the antimony and / or form compounds with the antimony and / or cause the antimony to fall into the mud rest of the battery and / or prevent antimony from depositing on the cathode. The surfactant or additive can also be added to the electrolyte, glass mat, battery case, pasting paper, paste mat, etc., or combinations thereof.

[0172] In certain embodiments, additives (e.g., nonionic surfactants, anionic surfactants, surfactants, or mixtures thereof) at least 0.5 g / m 2 , 1.0 g / m 2 , 1.5g / m 2 , 2.0 g / m 2 , 2.5g / m 2 , 3.0 g / m 2 , 3.5g / m 2 , 4.0g / m 2 , 4.5g / m 2 , 5.0g / m 2 , 5.5g / m2 , 6.0 g / m 2 , 6.5g / m 2 , 7.0 g / m 2 , 7.5g / m 2 , 8.0 g / m 2 , 8.5g / m 2 , 9.0 g / m 2 , 9.5g / m 2 or 10.0 g / m 2 or even about 25.0 g / m 2 Additives may be present at densities or add-on levels up to 0.5-15 g / m 2 , 0.5 to 10 g / m 2 , 1.0 to 10.0 g / m 2 , 1.5 to 10.0 g / m 2 , 2.0 to 10.0 g / m 2 , 2.5 to 10.0 g / m 2 , 3.0~10.0g / m 2 , 3.5 to 10.0 g / m 2 , 4.0~10.0g / m 2 , 4.5 to 10.0 g / m 2 , 5.0~10.0g / m2, 5.5~10.0g / m2, 6.0~10.0g / m2, 6.5~10.0g / m2, 7.0~10.0g / m2, 7.5~10.0g / m 2 , 4.5 to 7.5 g / m 2 , 5.0~10.5g / m 2 , 5.0~11.0g / m 2 , 5.0~12.0g / m 2 , 5.0~15.0g / m 2 , 5.0~16.0g / m 2 , 5.0~17.0g / m 2 , 5.0~18.0g / m 2 , 5.0~19.0g / m 2 , 5.0~20.0g / m 2 , 5.0~21.0g / m 2 , 5.0~22.0g / m 2 , 5.0~23.0g / m 2 , 5.0~24.0g / m 2 , or 5.0 to 25.0 g / m 2 may be present on the separator at a density or add-on level of

[0173] Application can also be performed by immersing the battery separator in the additive or a solution of the additive (solvent bath application) and removing the solvent if necessary (e.g., by drying). In this way, application of the additive can be combined with extraction, which is often applied, for example, during membrane manufacturing. Other preferred methods are spraying the additive onto the surface, or dip-coating, roller-coating, or curtain-coating one or more additives onto the surface of the separator.

[0174] In certain embodiments described herein, reduced amounts of ionic, cationic, anionic, or nonionic surfactants are added to the inventive separator. In such cases, desirable characteristics may include lower total organic carbon and / or lower volatile organic compounds (due to the lower amount of surfactant) that can make desirable inventive separators according to such embodiments.

[0175] Combine with fibrous mat In certain embodiments, exemplary separators according to the present disclosure can be combined (laminated or otherwise) with another layer, such as a fibrous layer or fibrous mat, having improved wicking properties and / or improved wettability or electrolyte retention. The fibrous mat can be a woven fabric, a nonwoven fabric, a fleece, a mesh, a net, a single layer, a multi-layer (each layer can have the same, similar, or different properties as the other layers), composed of fiberglass or synthetic fibers, a fleece or woven fabric made from synthetic fibers or a mixture of fiberglass and synthetic fibers or paper, or any combination thereof.

[0176] In certain embodiments, the fibrous mat (laminate or otherwise) or mat can be used as a carrier for additional materials. The additional materials can include, for example, rubber and / or latex, optionally silica, water, and / or one or more performance-enhancing additives, such as the various additives described herein, or any combination thereof. By way of example, the additional materials can be delivered in the form of a slurry, which can then be coated onto one or more surfaces of the fibrous mat to form a film, or can be dipped into the fibrous mat to impregnate it.

[0177] If a fibrous layer is present, it preferably has a surface area greater than that of the fibrous layer. Thus, when the porous membrane and fibrous layer are combined, the fibrous layer does not completely cover the porous layer. Preferably, at least two opposing edge regions of the membrane layer remain uncovered to provide edges for heat sealing to facilitate optional formation of pockets or envelopes and / or the like. Such fibrous mats can have thicknesses of at least 100 μm, and in some embodiments, at least about 200 μm, at least about 250 μm, at least about 300 μm, at least about 400 μm, at least about 500 μm, at least about 600 μm, at least about 700 μm, at least about 800 μm, at least about 900 μm, at least about 1 mm, at least about 2 mm, etc. The subsequently laminated separator may be shredded. In certain embodiments, the fibrous mat is laminated to the ribbed surface of the porous membrane. In certain embodiments, the improved separators described herein can be supplied in roll and / or cut strip form, providing handling and / or assembly advantages to battery manufacturers. Also, as previously mentioned, the improved separator can be a stand-alone separator sheet or layer without the addition of one or more fibrous mats or the like.

[0178] When the fibrous mat is laminated to the porous membrane, they can be bonded together by adhesives, heat, ultrasonic welding, compression, etc., or any combination thereof. The fibrous mat can also be a PAM or NAM bearing mat.

[0179] Example The following examples further illustrate at least selected separator embodiments of the present invention.

[0180] In certain embodiments, the following precipitated silicas can be used to obtain separators according to the invention: Median particle size 20.48 μm, mean particle size 24.87 μm (measured using a Coulter LS230) The silica samples shown in Table 3, having the following properties, were used in the preparation of the separator:

[0181] [Table 3]

[0182] The polyethylene separator made using the above silica had the following properties as shown in Tables 4 and 5: [Table 4]

[0183] [Table 5]

[0184] Additionally, in further embodiments, the following silica fillers, as described below in Table 6, were used in the separators described in Table 7 below:

[0185] [Table 6]

[0186] [Table 7]

[0187] Further examples: In the following series of examples, inventive reinforced flooded separators were made according to various embodiments of the present invention and tested against a control separator. The results are shown in Table 8 below.

[0188] [Table 8]

[0189] The results in Table 8 above show that the separator of Example A exhibited an approximately 20% lower ER compared to the control separator A. Similarly, the separator of Example B exhibited a 20% lower ER compared to the control separator A. These desirable ER results were obtained despite the fact that the porosity percentages of inventive separators A and B were within the acceptable range of porosity for such separators (60% ± 7.5%). Thus, the separator's novel and unexpected pore structure, coupled with the separator's porosity percentage being consistent (not significantly different) from that of known separators, contribute to the low ER.

[0190] Further examples: Several separators were formed in accordance with the present invention. These separators were compared to comparative separators. SEMs of the inventive separators were taken to image the shish kebab formation on the inventive separators.

[0191] Example 1: In Example 1, a reinforced flooded separator having a backweb thickness of 250 μm was prepared. In accordance with the present invention, a low ER separator was fabricated using UHMWPE, silica, and oil, where the silica used was a highly oil-absorbing silica. SEM images of the inventive low ER separator were taken. See Figure 17.

[0192] Three shish kebab regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of FIG. 17A, which is an SEM of the separator of Example 1. FTIR spectral profiles were then acquired for each of the three shish kebab regions. See FIGS. 17B-17D. The acquired FTIR spectra for each of the three shish kebab regions (No. 1, 2, and 3) of the SEM of FIG. 17A of the separator of Example 1 revealed the following peak position information and periodicity or repetition of shish kebab formation or morphology, as shown in Table 9 below:

[0193] [Table 9]

[0194] Finally, the average repeat or periodicity of the shish kebab morphology or structure was obtained to be 63 nm.

[0195] Example 2: Further, for Example 2, a reinforced flooded separator having a backweb thickness of 200 μm was fabricated using UHMWPE, silica, and oil in the same manner as in Example 1, except that the silica used was a highly oil-absorbent silica. SEM images of the inventive low ER separator were taken. See Figure 18A.

[0196] Three shish kebab regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of FIG. 18A, which is an SEM of the separator of Example 2. FTIR spectral profiles were then acquired for each of the three shish kebab regions. See FIGS. 18B-18D. The acquired FTIR spectra for each of the three shish kebab regions (No. 1, 2, and 3) of the SEM of FIG. 18A of the separator of Example 2 revealed the following peak position information and periodicity or repetition of the shish kebab formation or morphology, as shown in Table 10 below:

[0197] [Table 10]

[0198] Finally, the average repeat or periodicity of the shish kebab morphology or structure was obtained to be 63 nm.

[0199] Example 3: Regarding Example 3, a reinforced flooded separator having a backweb thickness of 250 μm was fabricated in accordance with the present invention using UHMWPE, silica, and oil in the same manner as in Example 1 above, except that the silica used was a highly oil-absorbent silica. An SEM of the inventive low ER separator was taken. See Figure 19A.

[0200] Three shish kebab regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of Figure 19A, which is an SEM of the separator of Example 3. FTIR spectral profiles were then acquired for each of the three shish kebab regions. See Figures 19B-19D. The acquired FTIR spectra for each of the three shish kebab regions (No. 1, 2, and 3) of the SEM of Figure 19A of the separator of Example 3 revealed the following peak position information and periodicity or repetition of shish kebab formation or morphology, as shown in Table 11 below:

[0201] [Table 11]

[0202] Finally, the average repeat or periodicity of the shish kebab morphology or structure was obtained to be 74 nm.

[0203] Example 4: For Example 4, a reinforced flooded separator having a backweb thickness of 250 μm was fabricated in accordance with the present invention using UHMWPE, silica, and oil in the same manner as in Example 1 above, except that the silica used was a high-oil-absorbency silica (a different high-oil-absorbency silica from the silica used in Examples 1-3 above; each of the high-oil-absorbency silicas used to fabricate the separators of Examples 1-5 ranged from about 230 to about 280 ml / 100 g). An SEM of the inventive low-ER separator was taken. See Figure 20A.

[0204] Three shish kebab regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of Figure 20A, which is an SEM of the separator of Example 4. FTIR spectral profiles were then acquired for each of the three shish kebab regions. See Figures 20B-20D. The acquired FTIR spectra for each of the three shish kebab regions (No. 1, 2, and 3) of the SEM of Figure 20A of the separator of Example 4 revealed the following peak position information and periodicity or repetition of shish kebab formation or morphology, as shown in Table 12 below:

[0205] [Table 12]

[0206] Finally, the average repeat or periodicity of the shish kebab morphology or structure was obtained to be 55 nm.

[0207] Example 5: For this example, Example 5, a reinforced flooded separator having a backweb thickness of 250 μm was fabricated in accordance with the present invention using UHMWPE, silica, and oil in the same manner as Example 1 above, except that the silica used was a highly oil-absorbent silica (a highly oil-absorbent silica different from the silica used in Examples 1-3 above and Example 4 above). An SEM of the inventive low ER separator was taken. See Figure 21A.

[0208] Three shish kebab regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of Figure 21A, which is an SEM of the separator of Example 5. FTIR spectral profiles were then acquired for each of the three shish kebab regions. See Figures 21B-21D. The acquired FTIR spectra for each of the three shish kebab regions (No. 1, 2, and 3) of the SEM of Figure 21A of the separator of Example 5 revealed the following peak position information and periodicity or repetition of shish kebab formation or morphology, as shown in Table 13 below:

[0209] [Table 13]

[0210] Finally, the average repeat or periodicity of the shish kebab morphology or structure was obtained to be 61 nm.

[0211] Comparative Example 1: A comparative polyethylene lead-acid battery separator was obtained with a backweb thickness of 250 μm. An SEM of the separator of Comparative Example 1 was taken. See Figure 22A.

[0212] Three regions, numbered No. 1, 2, and 3, respectively, were identified in the SEM of FIG. 22A, which is an SEM of the separator of Comparative Example 1. FTIR spectral profiles were then acquired for each of the three regions. See FIGS. 22B-22D. The FTIR spectra acquired for each of the three numbered regions (No. 1, 2, and 3) of the SEM of FIG. 22A of the separator of Comparative Example 1 revealed the following peak position information and periodicity or repetition information regarding the crystalline structure or morphology of the three regions, as shown in Table 14 below.

[0213] [Table 14]

[0214] Finally, the average repeat or periodicity of the crystalline structure or morphology of the identified regions was 170 nm.

[0215] Comparative Example 2: Another comparative polyethylene lead-acid battery separator was obtained with a backweb thickness of 250 μm. An SEM of the separator of Comparative Example 2 was taken. See Figure 23A.

[0216] The region of the separator SEM image numbered No. 1 was identified in the SEM of FIG. 23A, which is the SEM of the separator of Comparative Example 2. An FTIR spectral profile of that region was then acquired. See FIG. 23B. The acquired FTIR spectrum of region (No. 1) of FIG. 23A of the separator of Comparative Example 2 revealed the following peak position information and periodicity or repetition related to the crystalline structure and / or morphology of that region, as shown in Table 15 below:

[0217] [Table 15]

[0218] Therefore, the repeat or periodicity of the crystalline structure of the morphology of the identified regions was 212 nm.

[0219] Comparative Example 3: Yet another comparative polyethylene lead-acid battery separator was obtained commercially from Daramic, LLC. The separator had a backweb thickness of 250 μm. This separator was fabricated similarly to the separators described in Examples 1-5 above, except that the silica used to fabricate this separator did not have a high oil absorption value.

[0220] An SEM was taken of the separator of Comparative Example 3. See Figure 24. Observing Figure 25, there were no shish-kebab formations extending continuously for lengths of at least 0.5 μm in this SEM image of the microporous polyolefin membrane. Therefore, no areas were marked or further analyzed on the SEM.

[0221] Table 16 below compares the results obtained for the periodicity or repetition of the shish kebab region in Examples 1-5 to the results obtained for Comparative Examples 1-3.

[0222] [Table 16]

[0223] For Examples 1-5, the average repeat or periodicity of the shish kebab formation and / or crystal structure and / or morphology was 1 nm to 150 nm, preferably 10 nm to 120 nm, and even more preferably 20 nm to 100 nm. Such types of structures were not observed for the separators of Comparative Examples 1-3.

[0224] Further properties and characteristics of the separators of Examples 1-2 and 4-5 are shown in Table 17 below (while Table 3 above includes the properties of the separator of Example 3).

[0225] [Table 17]

[0226] Solid-state NMR example: For the two separator samples, the ratio of silanol groups (Si-OH) to elemental silicon (Si) (Si-OH) / Si was determined as described in great detail above. 29 Si solid-state NMR techniques were used to measure the NMR performance of the separator of Example 1, as well as a sample of a comparative separator of Comparative Example 4, which was made using the same type of polyethylene polymer and silica as the separator described above as Comparative Example 3, a polyethylene separator commercially available from Daramic, LLC, having a backweb thickness of 250 μm.

[0227] For each sample 29 Si-NMR spectra were obtained and are included in Figure 26. The Q2 signal was observed at approximately -93 ppm, while the Q3 signal was observed at approximately -103 ppm and the Q4 signal was observed at approximately -111 ppm. Each component peak was analyzed as shown in Figure 24 and the Q2:Q3:Q4 molar ratio was calculated using the information from Figure 24, with the results shown in Table 18 below:

[0228] [Table 18]

[0229] In the above results, the OH / Si ratio of the separator of Example 1 is 35% higher than that of the separator of Comparative Example 4, which means that the additional hydroxyl and / or silanol groups present on the silica of the inventive separator may contribute to the improved characteristics of the inventive separator, such as its desirable pore structure and / or morphology and its low ER.

[0230] conclusion According to at least selected embodiments, the present disclosure or invention is directed to separators, particularly separators for flooded lead-acid batteries, capable of reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; having reduced electrical resistance and / or increasing cold cracking amps. Additionally, disclosed herein are methods, systems, and battery separators for improving battery life; reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; reducing oxidation effects; reducing water loss; reducing internal resistance; increasing wettability; improving acid diffusion; improving cold cracking amps, improving uniformity, and any combination thereof, in at least reinforced flooded lead-acid batteries. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded lead-acid batteries, including an improved novel rib design and improved separator resilience. According to at least certain embodiments, the present disclosure or invention is directed to an improved separator for reinforced flooded lead-acid batteries, including a performance-enhancing additive or coating, increased oxidation resistance, increased porosity, increased void volume, amorphous silica, high oil absorption silica, high silanol group silica, silica with an OH to Si ratio of 21:100 to 35:100, shish-kebab structure or morphology, polyolefin microporous membranes comprising particulate fillers in an amount of 40% or more by weight of the membrane and polymer, such as ultra-high molecular weight polyethylene ("UHMWPE"), having extended chain crystals (shish formation) and folded chain crystals (kebab formation) and shish-kebab formation with an average repeat periodicity of kebab formation of 1 nm to 150 nm, reduced sheet thickness, reduced tortuosity, reduced caliper, reduced oil content, increased wettability, increased acid diffusion, and the like, and any combination thereof.

[0231] According to at least a first aspect of certain selected embodiments, a lead-acid battery separator includes a porous membrane having a polymer and a filler. The porous membrane includes at least a first surface having a first plurality of ribs extending from the first surface. The first plurality of ribs includes a first plurality of teeth or discrete peaks or protrusions, each of which is closely spaced to provide resilience to the separator. Such resilience may refer to the separator's ability to resist deflection when under pressure due to NAM swelling. Such proximity may be at least about 1.5 mm between teeth, peaks, or protrusions. The separator may further include a continuous base portion having a first plurality of teeth or discrete peaks or protrusions extending from the base portion.

[0232] In certain embodiments, the separator may include a continuous base portion having a first plurality of teeth or discrete peaks or projections extending from the base portion. The base portion may be wider than the width of the teeth or discrete peaks or projections. Additionally, the base portion may extend continuously between each of the teeth or discrete peaks or projections.

[0233] According to at least certain limited embodiments, the separator may comprise ribs that are one or more of the following: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, transverse ribs extending substantially in the widthwise direction of the separator with cracks therein, teeth, toothed ribs, serrated, serrated ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof.

[0234] At least a portion of the first plurality of ribs can be defined by an angle that may be neither parallel nor perpendicular to the edge of the separator. Further, the angle can be defined as an angle relative to the longitudinal direction of the porous membrane, and the angle can be one of the following: greater than zero degrees (0°) to less than one hundred and eighty degrees (180°), greater than one hundred and eighty degrees (180°) to less than three hundred and sixty degrees (360°). In certain aspects of the disclosed embodiments, the angle can vary throughout the plurality of ribs.

[0235] In certain limited aspects of the present invention, the first plurality of ribs may have a lateral spacing pitch of about 1.5 mm to about 10 mm, and the plurality of teeth or discrete peaks or protrusions may have a longitudinal spacing pitch of about 1.5 mm to about 10 mm.

[0236] In certain limited embodiments, the separator may include a second plurality of ribs extending from a second surface of the porous membrane. The second plurality of ribs may comprise one or more of the following: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof.

[0237] At least a portion of the second plurality of ribs can be defined by an angle that may be neither parallel nor perpendicular to the edge of the separator. Further, the angle can be defined as an angle relative to the longitudinal direction of the porous membrane, and the angle can be one of the following: greater than zero degrees (0°) to less than one hundred eighty degrees (180°), greater than one hundred eighty degrees (180°) to less than three hundred sixty degrees (360°). In certain aspects of the disclosed embodiments, the angle can vary throughout the plurality of ribs.

[0238] The second plurality of ribs have a horizontal or vertical spacing pitch of about 1.5 mm to about 10 mm.

[0239] The first surface may include one or more ribs that are of a different height than a first plurality of ribs located adjacent the edge of the lead-acid battery separator. Similarly, the second surface may include one or more ribs that are of a different height than a second plurality of ribs located adjacent the edge of the lead-acid battery separator.

[0240] In a limited embodiment, the polymer may be one of the following: polymer, polyolefin, polyethylene, polypropylene, ultra-high molecular weight polyethylene ("UHMWPE"), phenolic resin, polyvinyl chloride ("PVC"), rubber, synthetic wood pulp ("SWP"), lignin, glass fiber, synthetic fiber, cellulosic fiber, and combinations thereof.

[0241] A fibrous mat may be provided, which may be one of: fiberglass, synthetic fiber, silica, at least one performance enhancing additive, latex, natural rubber, synthetic rubber, and combinations thereof, and may be a nonwoven, woven, mesh, fleece, net, and combinations thereof.

[0242] Additionally, the separator may be a cut piece, a leaf, a pocket, a sleeve, a wrap, an envelope, and a hybrid envelope.

[0243] In at least certain limited exemplary embodiments, the separator may include elastic means for reducing deflection of the separator.

[0244] According to at least certain limited embodiments, the lead-acid battery may include a positive electrode and a negative electrode having a swollen negative electrode active material. A separator is provided such that at least a portion of the separator is disposed between the positive electrode and the negative electrode. An electrolyte is provided that substantially submerges at least a portion of the positive electrode, at least a portion of the negative electrode, and at least a portion of the separator. In at least certain limited embodiments, the separator may include a porous membrane made of at least a polymer and a filler. A first plurality of ribs may extend from a surface of the porous membrane. The ribs may be arranged to prevent acid starvation in the presence of NAM swelling, for example. The lead-acid battery may operate under any one or more of the following conditions: during operation, stationary, for backup power applications, for cycling applications, in a partial state of charge, and any combination thereof.

[0245] The rib may include a plurality of teeth or discrete peaks or protrusions. Each tooth or discrete peak or protrusion may be spaced at least about 1.5 mm from one another within the plurality of discrete peaks. The continuous base may include a plurality of teeth or discrete peaks or protrusions extending therefrom.

[0246] The first plurality of ribs may further be provided to enhance acid mixing in the battery, particularly during operation of the battery. The separator may be arranged parallel to the start and stop motion of the battery. The separator may be arranged adjacent to the anode, the cathode, or the separator. The mat may comprise a mat. The mat may be at least partially made of fiberglass, synthetic fiber, silica, at least one performance enhancing additive, latex, natural rubber, synthetic rubber, and any combination thereof. The mat may be a nonwoven fabric, a woven fabric, a mesh, a fleece, a net, and combinations thereof.

[0247] In at least certain limited embodiments of the present invention, the lead-acid battery may be a flat plate battery, a flooded lead-acid battery, an reinforced flooded lead-acid battery ("EFB"), a valve-regulated lead-acid ("VRLA") battery, a deep cycle battery, a gel battery, an absorbent glass mat ("AGM") battery, a tubular battery, an inverter battery, a vehicle battery, a start-light ignition ("SLI") vehicle battery, an idle-start-stop ("ISS") vehicle battery, an automobile battery, a truck battery, a motorcycle battery, an all-terrain vehicle battery, a forklift battery, a golf cart battery, a hybrid-electric vehicle battery, an electric car battery, an electric rickshaw battery, or an electric bicycle battery, or any combination thereof.

[0248] In certain embodiments, the battery can operate at a depth of discharge of about 1% to about 99%.

[0249] According to at least one embodiment, a microporous separator is provided that has reduced tortuosity. Tortuosity refers to the degree of curvature / bending over its length. Thus, a microporous separator with reduced tortuosity presents a shorter path for ions to travel through the separator, thereby reducing electrical resistance. Microporous separators according to such embodiments may have reduced thickness, increased pore size, more interconnected pores, and / or more open pores.

[0250] According to at least certain selected embodiments, microporous separators with increased porosity, or separators with different pore structures and / or reduced thicknesses, whose porosity is not significantly different from that of known separators, are provided. Ions move more quickly through microporous separators with increased porosity, increased void volume, reduced tortuosity, and / or reduced thickness, thereby reducing electrical resistance. Such thickness reductions can result in a reduction in the overall weight of the battery separator, which in turn reduces the weight of the reinforced flooded battery in which the separator is used, which in turn reduces the overall weight of the vehicle in which the reinforced flooded battery is used. Such thickness reductions can alternatively result in increased space for the positive electrode active material ("PAM") or negative electrode active material ("NAM") in the reinforced flooded battery in which the separator is used.

[0251] In accordance with at least certain selected embodiments, a microporous separator is provided that has increased wettability (in water or acid) that makes the separator more accessible to electrolyte ionic species, thus facilitating their passage across the separator and reducing electrical resistance.

[0252] According to at least one embodiment, a microporous separator is provided that has a reduced final oil content. Such a microporous separator will also promote reduced ER (electrical resistance) in an enhanced flooded battery or system.

[0253] The separator may contain an improved filler that has increased friability and can increase the porosity, pore size, internal pore surface area, wettability, and / or surface area of ​​the separator. In some embodiments, the improved filler has a highly structured morphology and / or a reduced particle size and / or a different amount of silanol groups than previously known fillers, and / or is more hydroxylated than previously known fillers. The improved filler may absorb more oil and / or allow for the incorporation of a larger amount of processing oil during separator formation without simultaneously shrinking or compacting when the oil is removed after extrusion. The filler can further reduce the so-called hydrated spheres of electrolyte ions, enhancing their transport across the membrane, thereby again lowering the overall electrical resistance or ER of the battery, e.g., an enhanced flooded battery, or system.

[0254] The filler or fillers can include various species (e.g., polar species such as metals) that increase ionic diffusion and facilitate the flow of electrolyte and ions across the separator, thus leading to a decrease in overall electrical resistance when such separators are used in flooded batteries, such as enhanced flooded batteries.

[0255] The microporous separator further includes a novel and improved pore morphology and / or a novel and improved fibril morphology, so that when the separator is used in a flooded lead-acid battery, the separator contributes to significantly reducing the electrical resistance in the flooded lead-acid battery. Such an improved pore morphology and / or fibril morphology can result in a separator whose pores and / or fibrils approximate a shish kebab (or shish kebab)-type morphology. Another way to describe the novel and improved pore shape and structure is a textured fibril morphology, in which silica nodes, i.e., silica nodules, exist in a kebab-type formation on the polymer fibrils (the fibrils are sometimes called shish) within the battery separator. Furthermore, in certain embodiments, the silica structure and pore structure of the separator of the present invention can be described as a skeletal structure or a spinal column structure or a spinal cord structure, with the silica nodes on the polymer kebabs, along with the polymer fibrils, oriented substantially perpendicular to the elongated central spines or fibrils (extended chain polymer crystals) that resemble vertebrae or intervertebral discs ("kebabs"), and in some cases approximate a spine-like shape ("shishi").

[0256] In some cases, improved batteries including improved separators with improved pore and / or fibril morphology may exhibit 20% lower electrical resistance, in some cases 25% lower electrical porosity, in some cases 30% lower electrical resistance, and in some cases even greater than a 30% reduction in electrical resistance ("ER") (potentially reducing the battery's internal resistance), while maintaining a balance of other important and desirable mechanical properties of lead-acid battery separators. Furthermore, in certain embodiments, the separators described herein have new and / or improved pore geometries that allow more electrolyte to flow through or fill the pores and / or voids compared to known separators.

[0257] Additionally, the present disclosure provides improved reinforced flooded lead-acid batteries that include one or more improved battery separators for the reinforced flooded battery, which combine the desirable features of reduced acid stratification, reduced voltage drop (or increased voltage drop persistence), and increased CCA for the battery, in some cases greater than 8%, or greater than 9%, or in some embodiments, greater than 10%, or greater than 15%. Such improved separators can result in reinforced flooded batteries whose performance matches or even exceeds that of AGM batteries. Such low electrical resistance separators can also be processed to result in reinforced flooded lead-acid batteries with reduced water loss.

[0258] The separator may include one or more performance-enhancing additives, such as surfactants, along with other additives or agents, residual oils, and fillers. Such performance-enhancing additives can reduce separator oxidation and / or even facilitate the transport of ions across the membrane, contributing to a lower overall electrical resistance of the enhanced flooded batteries described herein.

[0259] The lead-acid battery separators described herein are polyolefin microporous membranes comprising a polymer, e.g., polyethylene, e.g., ultra-high molecular weight polyethylene, a particulate filler, and an additive. The separator may include a microporous polyolefin membrane containing a plasticizer (which may optionally contain one or more further additives or agents). The microporous polyolefin membrane may contain a particulate filler in an amount of 40% by weight or more of the membrane. The ultra-high molecular weight polyethylene may also include a shish-kebab morphology polymer containing a plurality of extended chain crystals (shish formation) and a plurality of folded chain crystals (kebab formation), where the average repetition or periodicity of the kebab formation is 1 nm to 150 nm, preferably 10 nm to 120 nm, and more preferably 20 nm to 100 nm (at least for the rib-side portion of the separator).

[0260] The average repetition or periodicity of kebab formation is calculated according to the following definition: The surface of the polyolefin microporous membrane is observed using a scanning electron microscope ("SEM") after being subjected to metal deposition, and then an image of the surface is taken, for example, at an accelerating voltage of 1.0 kV and a magnification of 30,000 or 50,000 times. In the same visual field of the SEM image, at least three areas of continuous shish-kebab formations extending at least 0.5 μm in length are visible. The kebab periodicity of each displayed region is then calculated. The kebab periodicity was determined by Fourier transform of the intensity profile (contrast profile) obtained by projecting the shish-kebab formation in each displayed area perpendicular to the shish formation, and the average repetition period was calculated. The images are analyzed using common analytical tools, such as MATLAB (R2013a). -Spectrum detected in the short wavelength region of the spectral profile after Fourier transformation is considered to be noise. Such noise is mainly caused by distortion of the contrast profile. The contrast profile obtained for the separator according to the present invention appears to produce a square wave (rather than a sine wave). Furthermore, if the contrast profile is a square wave, the profile after Fourier transformation will be a sine function, and therefore will have multiple peaks in the short wavelength region in addition to the main peak that indicates the true kebab periodicity. Such peaks in the short wavelength region can be detected as noise.

[0261] In some embodiments, the lead-acid battery separators described herein comprise a filler selected from the group consisting of silica, precipitated silica, fumed silica, and precipitated amorphous silica; 29 The molar ratio of OH groups to Si groups in the filler, as measured by Si-NMR, is in the range of 21:100 to 35:100, in some embodiments 23:100 to 31:100, in some embodiments 25:100 to 29:100, and in certain preferred embodiments, 27:100 or greater.

[0262] The silanol groups change the silica structure from crystalline to amorphous because the relatively rigid covalent network of Si-O has partially disappeared. Amorphous-like silica, such as Si(-O-Si)2(-OH)2 and Si(-O-Si)3(-OH), has many twists, which can act as various oil absorption points. Therefore, increasing the amount of silanol groups (Si-OH) in silica increases oil absorption. Furthermore, the separators described herein, when containing silica with a higher amount of silanol groups and / or hydroxyl groups than silicas used in known lead-acid battery separators, may exhibit increased hydrophilicity and / or may have a higher void volume and / or may have certain aggregates surrounded by large voids.

[0263] The microporous separator further includes a new and improved pore morphology and / or a new and improved fibril morphology, so that when the separator is used in a flooded lead-acid battery, the separator contributes to significantly reducing the electrical resistance in the flooded lead-acid battery. Such improved pore morphology and / or fibril morphology contributes to significantly reducing the electrical resistance in the flooded lead-acid battery. The fibrils can result in a separator that approximates a shish kebab (or shish kebab)-type morphology. Another way to describe the new and improved pore shape and structure is a textured fibril morphology, in which silica nodes, i.e., silica nodules, are present in a kebab-type formation on the polymer fibrils (the fibrils are sometimes referred to as shish) in the battery separator. Furthermore, in certain embodiments, the silica and pore structure of the separators of the present invention can be described as a skeletal, spinal, or spinal structure, in which the silica nodes on the polymer kebabs are oriented along the polymer fibrils, resembling vertebrae or intervertebral discs ("kebabs"), and in some cases, substantially perpendicular to the elongated central spines or fibrils (extended chain polymer crystals) that approximate a spine-like shape ("shishi").

[0264] In certain selected embodiments, a vehicle may include a lead-acid battery generally as described herein. The battery may further include a separator as described herein. The vehicle may be a car, truck, motorcycle, all-terrain vehicle, forklift, golf cart, hybrid vehicle, hybrid-electric vehicle battery, electric vehicle, idle-start-stop ("ISS") vehicle, electric rickshaw, electric bicycle, electric bicycle battery, and combinations thereof.

[0265] In certain preferred embodiments, the present disclosure or invention provides a flexible battery separator whose components and physical attributes and features are synergistically combined to meet or, in certain embodiments, exceed the performance of previously known flexible separators (separators having a porous membrane of a polymer, e.g., polyethylene, plus a specified amount of performance-enhancing additives and ribs), thereby unexpectedly addressing a previously unmet need in the deep-cycle battery industry. In particular, the inventive separators described herein are stronger, less brittle, less likely to break, and more stable (less susceptible to degradation) over time than separators traditionally used in deep-cycle batteries. The flexible, performance-enhancing additive-containing, ribbed separators of the present invention combine the desirable robust physical and mechanical properties of polyethylene-based separators with the capabilities of conventional separators, while also improving the performance of battery systems employing the separator.

[0266] According to at least limited embodiments, aspects or objects disclosed or provided herein are new or improved separators, battery separators, reinforced flooded battery separators, batteries, cells, and / or methods of making and / or using such separators, battery separators, reinforced flooded battery separators, cells, and / or batteries. According to at least certain embodiments, the present disclosure or invention is directed to new or improved battery separators for reinforced flooded batteries. Additionally, disclosed herein are methods, systems, and battery separators having reduced ER, improved puncture strength, improved separator CMD stiffness, improved oxidation resistance, reduced separator thickness, reduced basis weight, and any combination thereof. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded batteries having reduced ER, improved puncture strength, improved separator CMD stiffness, improved oxidation resistance, reduced separator thickness, reduced basis weight, or any combination thereof. According to at least certain embodiments, separators are provided that include or exhibit reduced ER, improved puncture strength, improved separator CMD stiffness, improved oxidation resistance, reduced separator thickness, reduced basis weight, and any combination thereof. According to at least certain embodiments, separators are provided for battery applications, including flat plate batteries, tubular batteries, vehicle SLI and HEV ISS applications, deep cycle applications, golf car or golf cart and e-rickshaw batteries, batteries operating at partial state of charge ("PSOC"), inverter batteries, and storage batteries for renewable energy sources, and any combination thereof.

[0267] According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators for lead-acid batteries, such as flooded lead-acid batteries, and particularly reinforced flooded lead-acid batteries ("EFB"), and various other lead-acid batteries, such as gel and absorbent glass mat ("AGM") batteries. According to at least limited embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, elastomeric separators, balancing separators, EFB separators, batteries, cells, systems, methods including same, vehicles employing same, methods of manufacturing same, uses thereof, and combinations thereof. Further disclosed herein are methods, systems, and battery separators for improving battery life and reducing battery failure by reducing battery electrode acid depletion.

[0268] According to at least selected embodiments, the present disclosure or invention is directed to new or improved separators, battery separators, reinforced flooded battery separators, batteries, cells, and / or methods of manufacturing and / or using such separators, battery separators, reinforced flooded battery separators, cells, batteries, systems, methods, and / or vehicles employing the same. According to at least certain embodiments, the present disclosure or invention is directed to new or improved battery separators, elastomeric separators, balancing separators, flooded lead-acid battery separators, or reinforced flooded lead-acid battery separators, such as those useful for deep cycling and / or partial state of charge ("PSOC") applications. Such applications include, but are not limited to: electric machine applications, such as forklifts and golf carts (sometimes referred to as golf cars), electric rickshaws, electric bicycles, electric tricycles, etc.; automobile or truck (or HD truck) applications, such as start-light-ignition ("SLI") batteries, such as those used for internal combustion engine vehicles; idle-start-stop ("ISS") vehicle batteries; hybrid vehicle applications, hybrid-electric vehicle applications; for batteries with high power requirements, such as uninterruptible power supply ("UPS") or valve-regulated lead-acid ("VRLA"), and / or batteries with high CCA requirements; inverters; and energy storage systems, such as those found in renewable and / or alternative energy systems, e.g., solar and wind power systems.

[0269] According to at least selected embodiments, the present disclosure or invention is directed to separators, particularly separators for flooded lead-acid batteries, capable of reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; having reduced electrical resistance and / or increasing cold cracking amps. Additionally, disclosed herein are methods, systems, and battery separators for improving battery life; reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; reducing oxidation effects; reducing water loss; reducing internal resistance; increasing wettability; improving acid diffusion; improving cold cracking amps, improving uniformity, and any combination thereof, in at least reinforced flooded lead-acid batteries. According to at least certain embodiments, the present disclosure or invention is directed to improved separators for reinforced flooded lead-acid batteries, including an improved novel rib design and improved separator resilience. According to at least certain embodiments, the present disclosure or invention is directed to an improved separator for reinforced flooded lead-acid batteries, including a performance-enhancing additive or coating, increased oxidation resistance, increased porosity, increased void volume, amorphous silica, high oil absorption silica, high silanol group silica, silica with an OH to Si ratio of 21:100 to 35:100, shish-kebab structure or morphology, polyolefin microporous membranes comprising particulate fillers in an amount of 40% or more by weight of the membrane and polymer, such as ultra-high molecular weight polyethylene ("UHMWPE"), having extended chain crystals (shish formation) and folded chain crystals (kebab formation) and shish-kebab formation with an average repeat periodicity of kebab formation of 1 nm to 150 nm, reduced sheet thickness, reduced tortuosity, reduced caliper, reduced oil content, increased wettability, increased acid diffusion, and the like, and any combination thereof.

[0270] According to at least selected embodiments, the present disclosure or invention is directed to separators, elastic separators, balanced separators, and particularly separators for flooded lead-acid batteries capable of reducing or mitigating acid deficiency; reducing or mitigating acid stratification; reducing or mitigating dendrite growth; having reduced electrical resistance and / or capable of increasing cold cracking amps; having reduced electrical resistance and negative cross ribs; having low water loss, reduced electrical resistance and / or negative cross ribs; having dendrite blocking or prevention performance, properties and / or structure; having acid intermixing prevention performance, properties and / or structure; having reinforced negative cross ribs; having glass mat on the anode and / or cathode side of a PE membrane, piece, sleeve, fold, wrap, Z-wrap, S-wrap, pocket, envelope, etc.; having glass mat laminated to a PE membrane; and / or combinations or subcombinations thereof.

[0271] The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended to be illustrative of the claims and certain aspects of any functionally equivalent compositions and methods intended to be within the scope of the claims. Various modifications of the compositions and methods, in addition to those shown and described herein, are intended to be included within the scope of the appended claims. Furthermore, while only certain representative compositions and method steps disclosed herein have been specifically described, other combinations of compositions and method steps, even if not specifically recited, are intended to be included within the scope of the appended claims. Thus, although a combination of steps, elements, components, or elements is explicitly recited herein, other combinations of steps, elements, components, and elements are included even if not explicitly recited. As used herein, the word "comprising" and variations thereof are used synonymously with the word "including" and variations thereof and are open, non-limiting terms. Although the terms "comprising" and "including" are used herein to describe various embodiments, the terms "consisting essentially of" and "consisting of" can be used in place of "comprising" and "comprising" to provide more specific embodiments of the invention, which are also disclosed. Except in the examples, or unless otherwise noted, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims should be understood to be construed in light of significant digits and ordinary rounding approaches, at least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims.

[0272] The present invention may be embodied in other forms without departing from its spirit and essential attributes, and therefore, reference should be made to the appended claims, rather than the foregoing specification, as indicating the scope of the invention. Disclosed are components that can be used to practice the disclosed methods and systems. Where these and other components are disclosed herein, and combinations, subsets, interactions, groups, etc. of these components are disclosed, specific reference to each of these various individual and collective combinations may not be expressly disclosed, but it is understood that each is specifically contemplated and described herein for all methods and systems. This applies to all aspects of the present application, including, but not limited to, steps in disclosed methods. Thus, it is understood that various additional steps, if any, that can be performed can be performed with any specific embodiment or combination of embodiments of the disclosed methods.

[0273] The foregoing descriptions of structures and methods have been presented for purposes of example only. The examples are used to disclose example embodiments, including the best mode, and to enable any person skilled in the art to practice the invention, including making and using the devices or systems, and performing any incorporated methods. These examples are not intended to be exhaustive or to provide a complete understanding of the invention as disclosed herein. Furthermore, it is not intended to be limited to the steps and / or configuration thereof, and many modifications and variations are possible in light of the above teachings. The features described herein can be combined in any combination. The steps of methods described herein can 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 if they have structural elements that do not differ from the claim language, or if they include equivalent structural elements that are substantially different from the claim language.

[0274] The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended as illustrations of certain aspects of the claims. Any functionally equivalent compositions and methods are intended to be within the scope of the claims. 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, while only certain representative compositions and method steps disclosed herein have been specifically recited, other combinations of compositions and method steps, even if not specifically recited, are intended to be within the scope of the appended claims. Thus, although combinations of steps, elements, components, or elements may be explicitly recited herein, other combinations of steps, elements, components, and elements are included even if not explicitly recited.

[0275] 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 can be expressed herein as from "about" or "approximately" one particular value and / or to "about" or "approximately" 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 described event or circumstance may or may not occur, and that the description includes instances when said event or circumstance occurs and instances when said event or circumstance does not occur.

[0276] Throughout the description and claims of this specification, the word "comprise" and variations of this 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 words "consisting essentially of" and "consisting of" can be used in place of "comprising" and "including" to provide more specific embodiments of the present invention, which are also disclosed. "Exemplary" or "for example" means "one example of" and is not intended to indicate a preferred or ideal embodiment. Similarly, "such as" is used for descriptive or illustrative purposes, not limiting.

[0277] Unless otherwise noted, all numbers expressing shapes, dimensions, and the like used in the specification and claims should be understood to be construed in light of significant digits and ordinary rounding approaches but rather as an attempt to limit the application of the doctrine of equivalents to the scope of the claims.

[0278] 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 mentioned herein and the materials cited therein are specifically incorporated by reference.

[0279] Moreover, the invention illustratively disclosed herein may suitably be practiced in the absence of any element not specifically disclosed herein.

Claims

1. 1. A lead-acid battery separator comprising a porous membrane comprising a polymer and a filler, the porous membrane having at least a first surface and at least a first plurality of ribs or protrusions extending from the first surface; the first plurality of ribs extend parallel to one another at intervals of 2.5 mm to 6.0 mm, the height of the first plurality of ribs is 10 μm to 500 μm as measured from the surface of the porous membrane, the first plurality of ribs include a first plurality of peaks, each of the first plurality of peaks being at least 1.5 mm from a nearest adjacent peak; 10. A lead-acid battery separator, wherein the second plurality of ribs are one of the group consisting of: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, projections, nubs, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof.

2. 10. The lead-acid battery separator of claim 1, wherein said first plurality of discrete peaks further includes a continuous base portion extending therefrom, said continuous base portion being wider than a width of said discrete peaks.

3. the first plurality of ribs are one of the group consisting of: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, serrated, serrated ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, protrusions, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof; and at least a portion of the first plurality of ribs are defined at an angle that is neither parallel nor perpendicular to an edge of the separator; the angle varies among the at least some of the first plurality of ribs; or At least a portion of the first plurality of ribs are defined by an angle relative to a longitudinal direction of the porous membrane, the angle being: greater than zero degrees (0°) to less than one hundred eighty degrees (180°); 2. The method of claim 1, wherein the angle is selected from the group consisting of greater than 0 degrees (0°) to less than 360 degrees (360°). Lead acid battery separator.

4. At least a portion of the first plurality of ribs are defined by an angle relative to a longitudinal direction of the porous membrane, the angle being: greater than zero degrees (0°) to less than one hundred eighty degrees (180°); 4. The method of claim 3, wherein the angle is selected from the group consisting of greater than 0 degrees (0°) to less than 360 degrees (360°). Lead acid battery separator.

5. 10. The lead-acid battery separator of claim 1, wherein at least a portion of said first plurality of ribs have a height of between 600 μm and 800 μm.

6. 4. The lead-acid battery separator of claim 3, wherein at least a portion of said first plurality of ribs have a lateral spacing pitch of between 1.5 mm and 10 mm.

7. At least some of the first plurality of discontinuous teeth have longitudinal spacings of 1.5 mm to 10 mm.

4. The lead acid battery separator of claim 3 having a tack.

8. further comprising a second plurality of ribs extending from a second surface of the porous membrane; 10. The lead acid battery separator of claim 1, wherein the second plurality of ribs are one of the group consisting of: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, projections, nubs, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof.

9. the second plurality of ribs are one of the group consisting of: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, protrusions, nubs, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof; 9. The lead-acid battery separator of claim 8, wherein at least a portion of said second plurality of ribs are defined by an angle that is neither parallel nor perpendicular to an edge of said separator.

10. 10. The lead-acid battery separator of claim 9, wherein said angle varies among said at least some of said second plurality of ribs.

11. the second plurality of ribs are one of the group consisting of: solid ribs, discrete broken ribs, continuous ribs, discontinuous ribs, discontinuous peaks, discontinuous protrusions, angled ribs, linear ribs, longitudinal ribs extending substantially in the lengthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the porous membrane, transverse ribs extending substantially in the widthwise direction of the separator, discrete teeth, toothed ribs, battlements, battlemented ribs, curved ribs, sinusoidal ribs, arranged in a continuous zigzag sawtooth-like manner, arranged in a broken discontinuous zigzag sawtooth-like manner, grooves, channels, textured areas, protrusions, nubs, embossments, dimples, columns, mini-columns, porous, non-porous, mini-ribs, cross mini-ribs, and combinations thereof; 9. The lead-acid battery separator of claim 8, wherein at least a portion of said second plurality of ribs are defined by an angle relative to a longitudinal direction of said porous membrane, said angle being selected from the group consisting of: greater than zero degrees (0°) to less than one hundred eighty degrees (180°), and greater than one hundred eighty degrees (180°) to less than three hundred sixty degrees (360°).

12. 12. The lead-acid battery separator of claim 11, wherein said angle varies among said at least some of said second plurality of ribs.

13. 9. The lead-acid battery separator of claim 8, wherein at least a portion of said second plurality of ribs have a height of between 600 μm and 800 μm.

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