CN114678661B

CN114678661B - Lead-acid battery separator, lead-acid battery, vehicle and related methods

Info

Publication number: CN114678661B
Application number: CN202210366966.1A
Authority: CN
Inventors: 埃里克·H·米勒; M·尼尔·戈洛温; 阿希拉·克里斯哈拉莫斯; 马修·霍华德; 詹姆斯·P·佩里; J·凯文·威尔
Original assignee: Daramic LLC
Current assignee: Daramic LLC
Priority date: 2015-10-07
Filing date: 2016-10-07
Publication date: 2024-05-07
Anticipated expiration: 2036-10-07
Also published as: CN108292724A; CN108292724B; KR20180053421A; DE202016009027U1; JP2023086751A; CN114678661A; EP3360177A4; JP2018530126A; EP3360177A1; JP2022009317A; WO2017062781A1

Abstract

A battery separator, wherein the battery separator comprises: a porous backing web and a plurality of broken ribs extending from at least one surface of the backing web; the back mesh has an edge region and a center region; in the central area of the back net, the broken ribs are divided into a first group of broken ribs and a second group of broken ribs; the first group of broken ribs have a first inclination angle, and the second group of broken ribs have a second inclination angle; the first inclination angle and the second inclination angle are acute angles or obtuse angles; the first angle of inclination is different from the second angle of inclination; and a third group of broken ribs are respectively arranged at the edge part of the back net to form a plurality of rows of mutually-alternating raised areas and open areas which are respectively parallel to the edges of the partition boards, and the open areas are distributed between the two rows of broken ribs. The present invention can provide enhanced electrolyte mixing and significantly reduced acid stratification.

Description

Lead-acid battery separator, lead-acid battery, vehicle and related methods

The application is a divisional application, and the priority date is 2015, 10 and 7; the original international application date is 2016, 10 and 7; the original International application number is PCT/US2016/056009; the date of entering the China national stage is 2018, 6, 5 days, and the China application number is 201680071219.8; the original name of the application is' lead-acid battery separator with improved performance, battery thereof, vehicle with the battery and related method.

Cross Reference to Related Applications

The present application claims U.S. provisional patent application Ser. No.62/238,373 filed on 10/7 of 2015; PCT patent application serial No. PCT/US2016/012805 filed on 1/11/2016 (which claims priority from U.S. provisional patent application serial No.62/238,373 filed on 10/7/2015); and priority and equity of No.62/385,347 filed 9/2016. The entire contents of each of which are hereby incorporated by reference in their entirety.

Technical Field

In accordance with at least selected embodiments, the present disclosure relates to improved lead acid batteries, such as flooded lead acid batteries, improved systems including lead acid batteries and/or battery separators, improved vehicles including such systems, methods of manufacture or use, or combinations thereof. In accordance with at least certain embodiments, the present disclosure or invention relates to improved flooded lead acid batteries, improved battery separators for such batteries, and/or methods of making, testing, or using such improved flooded lead acid batteries, or combinations thereof. Additionally, disclosed herein are methods, systems, batteries, and/or battery separators for reducing acid stratification, increasing battery life and performance in flooded lead acid batteries, as well as in flooded lead acid batteries operating in a partially charged state.

Background

To reduce fuel consumption and tailpipe emissions, automotive manufacturers have implemented varying degrees of electronic hybrid (ELECTRICAL HYBRIDIZATION). One form of Hybrid Electric Vehicle (HEV) is sometimes referred to as a "micro HEV" or "micro hybrid. In such a micro HEV or similar vehicle, the vehicle may have an idle start/stop (ISS) function, wherein the engine may be shut off at various points during idle start/stop and/or regenerative braking. While this increases the fuel economy of the vehicle, it also increases the battery burden that must power auxiliary devices (e.g., air conditioners, media players, etc.) when the vehicle is not in operation.

Conventional vehicles (e.g., automobiles without start/stop capabilities) may use conventional flooded lead acid batteries, such as SLI lead acid batteries. Since the engine is never shut down, power is extracted from the battery only when the engine is started. As such, the battery is typically in an overcharged state, rather than in a partially charged state. For example, such a conventional flooded lead acid battery, because it is typically in an overcharged state, may exist in a state of charge of greater than 95%, greater than 96%, greater than 97%, greater than 98%, greater than 99%, or even greater than 100%. Upon overcharge, bubbles (e.g., hydrogen bubbles) are generated within conventional lead acid batteries, and these circulating bubbles are used to mix the liquid electrolyte (acid) within the battery.

On the other hand, a vehicle with start/stop constantly draws power from the battery, so the battery is always in a partially charged state. At partial charge, no bubbles are generated and internal mixing of the electrolyte is greatly reduced, resulting in acid stratification within the battery. Thus, acid stratification is a problem in starting/stopping flooded lead acid batteries and various enhanced flooded batteries, whereas acid stratification is not a problem for more conventional or traditional flooded lead acid batteries, which operate at overcharge or full charge (or near full charge).

Acid stratification is a term for the process of concentrating concentrated sulfuric acid at the bottom of the cell, resulting in a correspondingly higher water concentration at the top of the cell. Acid stratification is undesirable in flooded lead acid batteries, such as enhanced flooded lead acid batteries or start/stop flooded lead acid batteries. The reduced acid content at the top of the electrode may inhibit uniformity and charge acceptance within the battery system and may increase the variation in internal resistance from top to bottom along the height of the battery. An elevated acid level at the bottom of the battery can artificially increase the battery voltage, which can interfere with the battery management system and can send an unexpected/erroneous health signal condition to the battery management system. Overall, acid stratification can lead to higher electrical resistance of the cell components, which can lead to electrode problems and/or reduced cell life. In view of the growing use of start/stop batteries and/or other enhanced flooded lead acid batteries in hybrid and all-electric vehicles expected to increase vehicle fuel efficiency and reduce carbon dioxide emissions, solutions to reduce acid stratification and/or to improve acid mixing are highly desirable.

In some cases, acid stratification may be avoided using VRLA (valve regulated lead acid) technology, where the acid is immobilized by a gel electrolyte and/or an Absorbent Glass Mat (AGM) battery separator system. In contrast to free fluid electrolytes in flooded lead acid batteries, in VRLA batteries, the electrolyte is absorbed on a fiber or fiber material, such as a glass fiber mat, a polymer fiber mat, a gel electrolyte, and the like. However, the manufacturing cost of VRLA AGM battery systems is far higher than flooded battery systems. The VRLA-AGM technique may be more susceptible to overcharging in some situations, may dry out at high temperatures, may gradually drop in capacity, and may have a lower specific energy. Similarly, in some cases, gel VRLA technology may have a higher internal resistance and may have reduced charge acceptance.

Thus, there is a need to further develop enhanced flooded lead acid batteries, e.g., enhanced flooded start/stop batteries, that do not experience acid stratification during use and/or exhibit reduced or significantly reduced levels of acid stratification during use. There is a need for improved enhanced flooded lead acid batteries that have improved uniformity and performance over previously available and that have the same or even better performance than certain VRLA AGM batteries.

Disclosure of Invention

The object of the present invention is to provide a lead acid battery and a separator therefor, which can improve the mixing of acids in a flooded lead acid battery.

To this end, the present invention provides a battery separator comprising: a porous backing web and a plurality of broken ribs extending from at least one side of the backing web; at least a portion of the plurality of broken ribs is disposed obliquely. The broken ribs may be arranged in different areas in different patterns.

During movement of the battery, the separator is positioned parallel to the start and stop movement of the battery.

The above and other needs are addressed by the present disclosure or invention, according to at least selected embodiments. For example, in accordance with at least certain embodiments, the present disclosure or invention relates to new, improved or optimized flooded lead acid batteries, systems and separators for enhanced flooded lead acid batteries, and methods of making, testing and/or using the same, and/or vehicles including the same.

Disclosed herein are new, improved or optimized enhanced flooded lead acid batteries with a specific class of separators. It has surprisingly been found that by appropriate selection of separator surface properties (and optionally specific panel and separator orientations in the vehicle) acid stratification can be reduced and/or prevented and a corresponding increase in battery performance can be observed, approaching, equivalent to or even higher than that of certain VRLA AGM or VRLA-AGM batteries. Furthermore, it has surprisingly been found that such operation of the cells and separators of the present invention, when operated using the separators described herein and one or more of the cells described herein, facilitates improved acid mixing or recycling and/or reduces or prevents acid stratification altogether without the need for mechanical means or tools (e.g., pumps for acid mixing). Various embodiments are described in further detail below.

In accordance with at least selected embodiments, aspects or objects, the present disclosure or invention relates to improved lead acid batteries, such as flooded lead acid batteries, improved systems including lead acid batteries and battery separators, improved vehicles including such systems, and/or methods of manufacture and/or use.

In accordance with at least selected embodiments, aspects, or objects, the present disclosure may provide an enhanced flooded lead acid battery, such as an enhanced flooded start/stop battery, that does not experience acid stratification and/or exhibits reduced or significantly reduced acid stratification when in use, an enhanced flooded lead acid battery having improved uniformity, such as acid mixing uniformity, etc., an improved battery operating in a partially charged state, and/or performance, and/or an improved enhanced flooded lead acid battery that is at least comparable to or exceeds the performance capabilities of certain VRLA-AGM batteries, as compared to previously existing.

Drawings

Fig. 1 includes a series of photographs comparing battery cells that have undergone 90 stop/start events or cycles. According to an exemplary embodiment, the top row shows battery cells with serrated rib separators. The bottom row depicts a battery cell having a conventional solid rib separator with such solid ribs extending vertically along the separator.

Fig. 2 includes a series of photographs comparing battery cells that have undergone 60 stop/start events or cycles, and then been at rest overnight. The test cells had separators similar to that shown in fig. 1, with the top row showing a serrated ribbed separator according to an exemplary embodiment and the bottom row showing a cell with a conventional solid ribbed separator.

Fig. 3 includes a series of photographs comparing battery cells that have undergone 90 stop/start events or cycles. The top row of test cells were provided with separators having more closely spaced serrated ribs than those shown in fig. 1 and 2. The bottom row is provided with battery cells having conventional solid rib separators, with the solid ribs extending vertically along the separator.

Fig. 4 includes a series of photographs comparing battery cells that have undergone 90 stop/start events or cycles. The top row depicts a battery cell with a dimpled separator according to an exemplary embodiment. The bottom row depicts a battery cell having a conventional separator comprising a solid large rib and a solid small rib, wherein the large and small solid ribs extend vertically along the separator.

Fig. 5 includes a series of photographs comparing battery cells that have undergone 90 stop/start events or cycles. The top row depicts a battery cell with a dimpled separator according to an exemplary embodiment. The bottom row shows battery cells with separators that include solid ribs extending vertically along the separator and engaging the depressions.

Fig. 6 includes a series of photographs comparing battery cells that have undergone 90 stop/start events or cycles. The top row depicts a battery cell with a dimpled separator according to an exemplary embodiment, and the bottom row depicts a battery cell with a separator that includes solid ribs extending along the separator along a diagonal (along a slight angle relative to the vertical of the separator).

Fig. 7A and 7B include photographs of a comparison of a conventional solid ribbed baffle (7A) and no baffle at all (7B) in a tank filled with 1.28 specific gravity acid (which is mixed).

Fig. 8 includes photographs of battery cells constructed using serrated ribbed separators according to the present disclosure prior to testing acid stratification.

Fig. 9 includes photographs of the battery cell of fig. 8 assembled within a housing for acid stratification testing. Lead tape is placed over the electrode and separator set.

Fig. 10 includes photographs of cross-sectional views of serrations or serrated ribs on a separator used in accordance with various embodiments described herein.

Fig. 11 includes two views of a profile of a serrated rib baffle used in accordance with various embodiments described herein.

Fig. 12 depicts a graph of the conductivity of sulfuric acid solution at 25 ℃ (77°f). The graph helps to understand that acid stratification can result in non-uniform current flow due to conductivity differences in the high and low acid regions of the cell and/or battery. The subzone graph represents data collected from the following web pages, which were accessed at day 2016, 7, 26: http:// myweb.wit. Edu/sandinic/Research/conductivity%20v%20concentration. Pdf; wherein conductivity is measured in siemens/cm and expressed as a function of sulfuric acid solution concentration in weight percent.

Fig. 13 includes photographs of battery cells constructed similarly to the battery cells shown in fig. 6. However, for the battery cell depicted in fig. 13, the separator is inserted into the system perpendicular to the direction of movement of the vehicle, while for the battery cell shown in fig. 6, the separator is inserted into the system parallel to the direction of movement.

Fig. 14 includes photographs of battery separators containing serrated ribs according to various embodiments described herein for use in enveloping electrodes to make start/stop automotive flooded lead acid batteries for testing, the results of which are described below.

15A-15D include diagrams of a plurality of serrated profiles of a separator according to various embodiments herein. Various optimized profiles for separators for improving and enhancing acid mixing are disclosed herein, and the diagrams set forth in fig. 15A-15D are merely examples of such optimized profiles; many other optimized profiles fall within the scope of the improved separators, batteries, systems, and methods described and claimed herein.

Fig. 16 includes a graph depicting a cycling test of one embodiment of an enhanced flooded battery or a flooded battery operating in an enhanced mode.

Fig. 17A shows a horizontal acceleration curve with lateral or side-to-side motion experienced by a battery separator modeled as sinusoidal acceleration for Computational Fluid Dynamics (CFD) analysis. Fig. 17B shows a visual comparison of solid rib baffles and serrated rib baffles, each at about 6 seconds (as shown), and each undergoing the motion defined in fig. 17A, and analyzed using CFD. Both separators analyzed encapsulate the positive plate ("positive encapsulation" or "positive wrap").

Fig. 18A shows a solid rib separator undergoing the motion defined in fig. 17A, accelerated horizontally for 60 seconds, and analyzed using CFD to show mixing of layered electrolyte of a flooded lead acid battery. Fig. 18B depicts the volumetric uniformity of the acid portion of the analysis of fig. 18A.

Fig. 19A shows a serrated rib separator undergoing the motion defined in fig. 17A, over 60 seconds, and analyzed using CFD to show mixing of layered electrolytes of a flooded lead acid battery. Fig. 19B depicts the volumetric uniformity of the analysis of fig. 19A.

FIGS. 20A-20B depict a comparison of the CFD analysis of FIGS. 18A-18B and FIGS. 19A-19B.

FIG. 21 defines a rocking motion for use in CFD analysis of a serrated rib baffle.

FIG. 22 shows a graphical representation of CFD analysis of a serrated rib baffle undergoing the motion described in FIG. 21.

Fig. 23 is a schematic illustration of a separator that encapsulates the negative electrode plate ("negative encapsulation" or "negative wrap") of a flooded lead acid battery, such as an enhanced flooded lead acid battery and/or an ISS flooded lead acid battery.

FIG. 24A is a graphical representation of a CFD analysis of a negative encapsulated serrated rib separator plate undergoing lateral movement, and further compared to a graphical representation of a CFD analysis of a positive encapsulated serrated rib separator plate undergoing the same lateral movement. FIG. 24B is a graphical representation of the volumetric uniformity of the negative enveloping serrated rib separator of FIG. 24A. FIG. 24C is a graphical comparison of volume uniformity of negative and positive-packed serrated rib separators.

25A-25F depict variations in the form of broken ribs according to an exemplary embodiment of the present disclosure.

26A-26G illustrate a battery separator with broken ribs according to an exemplary embodiment of the present disclosure and as defined in the form shown therein.

FIG. 27A is a graphical comparison of CFD analysis of negative enveloped serrated rib separators and negative enveloped broken rib separators undergoing lateral movement. Fig. 27B depicts a comparison of the volumetric uniformity of several CFD analyses of a previously described separator plate undergoing lateral movement.

Fig. 28A is a graphical comparison of CFD analysis of negative-packed solid rib separators and negative-packed broken rib separators undergoing lateral movement. Fig. 28B depicts a comparison of the volumetric uniformity of several CFD analyses of solid rib, serrated rib and broken rib separators (all negative envelopes).

Fig. 29A details a separator plate having three regions of different rib formation. Fig. 29B depicts the rib breaking variable of a three-zone rib-breaking separator. Fig. 29C depicts the rib breaking variable of a single-zone rib-breaking separator.

FIGS. 30A-30H depict variations of multi-zone split rib-type baffles.

Figure 31 depicts a graphical representation of CFD analysis of four different three-zone rib-type negative encapsulation separators.

Fig. 32A is a graphical comparison of CFD analysis of a negative-packed three-zone rib-shaped separator and a negative-packed single-zone rib-shaped separator (as shown in fig. 26D) undergoing lateral movement. Fig. 32B depicts a comparison of the volumetric uniformity of several CFD analyses of a previously described separator plate undergoing lateral movement.

33A-33C illustrate the head space of a battery having a splash shield, according to an exemplary embodiment of the present disclosure.

Fig. 34A-34I illustrate variations of exemplary embodiments of the present disclosure.

Fig. 35 depicts a separator for a high cell having a ribbed form substantially as shown in fig. 26D.

Fig. 36 depicts the volumetric uniformity of CFD analysis of the separator depicted in fig. 35 versus other separator designs over time.

Fig. 37 depicts a velocity profile time history comparison of the inventive concept 1 high acid mixing profile with a conventional solid baffle high profile.

Fig. 38 depicts an exemplary separator of the present invention in the form of a broken rib that may be placed, for example, between a flat separator and an electrode.

39A-39C illustrate exemplary embodiments depicting power separator profiles, spacing, and headspace size values as in a high cell or cell housing.

Fig. 40 and 41 show profile prototypes of exemplary acid hybrid profiles of the present invention.

Fig. 42 includes images showing the mixing benefits of the inventive profile over conventional solid rib profiles.

Detailed Description

In various embodiments described herein, separators are used that enhance electrolyte mixing and/or circulation in flooded lead acid batteries. In certain embodiments, a separator is employed that reduces acid stratification. In various embodiments, a lead acid battery is disclosed in which acid stratification is substantially reduced as compared to known batteries because an improved or enhanced separator or separator system is used for acid mixing, and to prevent or at least reduce acid stratification and the negative effects of acid stratification. Such a battery can be used, for example, in a battery of a running vehicle. And in various embodiments, movement of a vehicle (e.g., an electric vehicle or a portion of an electric vehicle comprising a start/stop lead acid battery) for actual mixing of acid or electrolyte in combination with the enhanced battery separator described herein, unexpectedly results in a significant reduction in acid stratification shown herein and a significant improvement in acid mixing shown herein within a start/stop flooded lead acid battery and/or an enhanced flooded lead acid battery or a battery operating in an enhanced mode. For example, in various embodiments herein, stopping and starting of a start/stop electric vehicle provides energy to mix acid/electrolyte within an enhanced flooded lead acid battery and improve acid mixing and reduce or completely prevent acid stratification.

Exemplary embodiments of the separators (preferably reinforced acid-mixed separators, blades, sleeves, wraps, bags, or envelopes) described herein are preferably made from porous membranes (e.g., microporous membranes having pores less than about 1 μm, macroporous membranes having mesopores or pores greater than about 1 μm, porous polymer membranes, or porous filled polymer membranes) made from suitable natural or synthetic materials, such as polyolefin, polyethylene, polypropylene, phenolic resin, polyvinylchloride (PVC), rubber, synthetic Wood Pulp (SWP), glass fibers, cellulose fibers, or combinations thereof, more preferably microporous membranes made from thermoplastic polymers. Preferred microporous membranes can have a pore diameter of about 0.1 μm (100 nm) and a porosity of about 60%. In principle, the thermoplastic polymer may comprise all acid resistant thermoplastic materials suitable for use in lead acid batteries. Preferred thermoplastic polymers include polyethylene and polyolefin. Polyethylene-based materials include, for example, PVC. Polyolefins include, for example, polyethylene, ultra High Molecular Weight Polyethylene (UHMWPE), and polypropylene. A preferred embodiment may comprise a mixture of filler (e.g. silica) and UHMWPE. Generally, a preferred separator may be prepared by mixing about 30 wt% silica with about 10 wt% UHMWPE and about 60% process oil in an extruder. The mixture may also include minor amounts of other additives or agents (e.g., wetting agents, colorants, antistatic additives, similar materials, or combinations thereof) that are common in the separator art and extruded into a flat sheet shape. A possibly preferred polyolefin separator may be a microporous sheet of silica-filled polyolefin (with or without residual oil and one or more additives or surfactants) having serrated ribs, protrusions, stacks, pits, embossments, and combinations thereof on one or more surfaces (and which may preferably provide an acid mixing effect related to electrolyte sloshing caused by vehicle motion).

The separator is preferably made of a polyolefin, such as polypropylene, an ethylene-butene copolymer, preferably polyethylene, more preferably a high molecular weight polyethylene, i.e. a polyethylene having a molecular weight of at least 600,000 or a high density polyethylene, such as a polyethylene having a molecular weight of at least 500,000. In some embodiments, one or more ultra high molecular weight polyethylenes are used, i.e., polyethylenes having a molecular weight of at least 1,000,000, particularly greater than 4,000,000, and in some cases from 5,000,000 to 8,000,000 (as measured by a viscometry method and calculated by the Margolie equation), a standard load melt index [ as determined according to ASTM D1238 (condition E) using standard load 2,160g ] of substantially 0, and a viscosity number of no less than 600ml/g, preferably no less than 1000ml/g, more preferably no less than 2,000ml/g, and most preferably no less than 3,000ml/g (as determined at 130 ℃ in a solution of 0.02g polyolefin in 100g decalin).

According to at least one embodiment, the separator is made of Ultra High Molecular Weight Polyethylene (UHMWPE) mixed with process oil and silica, such as precipitated silica and/or fumed silica. According to at least one other embodiment, the separator is composed of Ultra High Molecular Weight Polyethylene (UHMWPE) mixed with process oil, additives and silica (e.g., precipitated silica). The separator preferably comprises a homogeneous mixture of 8 to 100% by volume of polyolefin, 0 to 40% by volume of plasticizer and 0 to 92% by volume of inert filler material. In some cases, the preferred filler is dry finely divided silica. However, the filler may be selected from the group consisting of silica, mica, montmorillonite, kaolinite, asbestos, talc, diatomaceous earth, vermiculite, natural and synthetic zeolites, cement, calcium silicate, clay, aluminum silicate, sodium aluminum silicate, aluminopolysilicates, alumina silica gel, glass particles, carbon black, activated carbon, carbon fiber, charcoal, graphite, titanium oxide, iron oxide, copper oxide, zinc oxide, lead oxide, tungsten, antimony oxide, zirconium oxide, magnesium oxide, aluminum oxide, molybdenum disulfide, zinc sulfide, barium sulfate, strontium sulfate, calcium carbonate, magnesium carbonate, and the like, and various combinations thereof.

Preferred plasticizers are petroleum oils and/or waxes. Since the plasticizer is the component most easily removed from the polymer-filler-plasticizer composition, it can be used to impart porosity to the battery separator.

The separator has an average pore diameter of less than 1 μm. Preferably, more than 50% of the pores have a diameter of 0.5 μm or less. It may be preferred that at least 90% of the pores have a diameter of less than 0.9 μm. The microporous separator preferably has an average pore size in the range of 0.05 to 0.9 μm, in some cases 0.1 to 0.3 μm.

In some cases, pore size may be measured using mercury porosimetry as described in Ritter, h.l. and Drake, l.c. in ind. According to this method, mercury is pressed into holes of different sizes by varying the pressure exerted on the mercury by a porosimeter (porosimeter model 2000, carlo Erba). The pore distribution can be determined by evaluating the raw data with MILESTONE software.

The thickness of the separator is preferably greater than 0.1mm and less than or equal to 5.0mm. The thickness of the separator may be in the range of 0.15-2.5mm, 0.25-2.25mm, 0.5-2.0mm, 0.5-1.5mm, or 0.75-1.5mm (where such thickness is considered the thickness of the entire separator, including any ribs, protrusions, dimples, etc.). In some cases, the separator may be about 0.8mm or 1.1mm thick. The separator may or may not have a laminate or some other layer (e.g., a nonwoven layer and/or an AGM layer) adhered to one or more surfaces thereof. Also, one or both electrodes may be wrapped with one or more glass fiber mats or layers and/or with a porous plate wrap.

In various possibly preferred embodiments, the microporous polyolefin separator layer comprises ribs, such as serrations, stacks, angled ribs or broken ribs, or combinations thereof. Preferred ribs may be 8 μm to 1mm high and may be spaced 1 μm to 20mm apart, while preferred backing web thicknesses for microporous polyolefin separator layers (excluding ribs or embossments) may be about 0.05mm to about 0.50mm (e.g., about 0.25mm in certain embodiments). For example, the ribs may be spaced 0.05mm、0.1mm、0.2mm、0.3mm、0.4mm、0.5mm、0.6mm、0.7mm、0.8mm、0.9mm、1.0mm、1.2mm、1.4mm、1.6mm、1.8mm、2.0mm、2.25mm、2.5mm、2.75mm、3mm、4mm、5mm、6mm、7mm、8mm、9mm or 10mm apart. In some embodiments, the ribs may be in a form such that they may be at 0 ° to 90 ° relative to each other on one side of the separator layer or on both sides of the polyolefin separator. In some embodiments, the acid mixing rib may be a front side, a positive or a positive rib. Various forms including ribs on both sides of the separator or separator layer may include positive and negative longitudinal ribs or intersecting ribs, such as smaller, more closely spaced negative longitudinal ribs or intersecting ribs or mini-ribs, on the second or back side of the separator. In some cases, such negative longitudinal ribs or cross ribs may be about 0.025mm to about 0.1mm in height, and preferably about 0.075mm, but may be as large as 0.25mm. Other forms may include ribs on both sides of the separator layer with negative mini ribs on the second or back side of the separator (mini ribs extending in the same direction relative to the lateral direction as compared to the main ribs on one side of the separator). In some cases, the height of such negative mini-ribs may be about 0.025mm to about 0.25mm, and preferably about 0.050mm to about 0.125.

In certain preferred embodiments, the ribs may be serrated. The serrations may have an average tip length of from about 0.05mm to about 1mm. For example, the average tip length may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm.

The serrations may have an average bottom length of about 0.05mm to about 1mm. For example, the average bottom length may be greater than or equal to about 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm.

The serrations, if present, may have an average height of about 0.05mm to about 4mm. For example, the average height may be greater than or equal to about 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm. For embodiments in which the serration height is the same as the rib height, the serration rib may also be referred to as a protrusion. Such a range may be suitable for separators for industrial traction type start/stop cells, which may typically have a total thickness of about 1mm to about 4mm, and automotive start/stop cells, which may be somewhat smaller (e.g., typically about 0.3mm to about 1 mm).

The serrations may have an average center-to-center distance of from about 0.1mm to about 50 mm. For example, the average center-to-center distance may be greater than or equal to about 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.25mm, or 1.5mm; and/or less than or equal to about 1.5mm, 1.25mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, or 0.2mm.

The serrations may have an average height to bottom width ratio of about 0.1:1 to about 500:1. For example, the ratio of the average height to the bottom width may be greater than or equal to about 0.1:1, 25:1, 50:1, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1, or 450:1; and/or less than or equal to about 500:1, 450:1, 400:1, 350:1, 300:1, 250:1, 200:1, 150:1, 100:1, 50:1, or 25:1.

The serrations may have an average bottom width to top width ratio of from about 1000:1 to about 0.1:1. For example, the average bottom width to top width ratio may be greater than or equal to about 0.1:1、1:1、2:1、3:1、4:1、5:1、6:1、7:1、8:1、9:1、10:1、15:1、20:1、25:1、50:1、100:1、150:1、200:1、250:1、300:1、350:1、450:1、500:1、550:1、600:1、650:1、700:1、750:1、800:1、850:1、900:1、950:1; and/or less than or equal to about 1000:1、950:1、900:1、850:1、800:1、750:1、700:1、650:1、600:1、550:1、500:1,450:1、400:1、350:1、300:1、250:1、200:1、150:1、100:1、50:1、25:1、20:1、15:1、10:1、9:1、8:1、7:1、6:1、5:1、4:1、3:1、2:1 or 1:1.

In some embodiments, the separator may be dimpled. The depressions are typically raised features or bumps on one or more surfaces of the separator plate. The thickness of the pits may be 1-99% of the thickness of the separator. For example, the average thickness of the pits may be less than about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the separator. The depressions may be aligned along the baffle. The rows or columns may be spaced about 1 μm to about 10mm apart. For example, the rows may be about 0.05mm、0.1mm、0.2mm、0.3mm、0.4mm、0.5mm、0.6mm、0.7mm、0.8mm、0.9mm、1.0mm、1.2mm、1.4mm、1.6mm、1.8mm、2.0mm、2.25mm、2.5mm、2.75mm、3mm、4mm、5mm、6mm、7mm、8mm、9mm or 10mm. Instead, the pits may be arranged in a random array or in a random manner.

The pits may have an average pit length of about 0.05mm to about 1mm. For example, the average pit length may be greater than or equal to about 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm.

The pits may have an average pit width of about 0.01mm to about 1.0 mm. For example, the average pit width may be greater than or equal to about 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm.

The dimples may have an average center-to-center distance of from about 0.10mm to about 50 mm. For example, the average center-to-center distance may be greater than or equal to about 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.25mm, or 1.5mm; and/or less than or equal to about 1.5mm, 1.25mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, or 0.2mm.

The shape of the pit may be quadrangular, such as square and rectangular. The pits may have an average pit length to pit width ratio of about 0.1:1 to about 100:1. For example, the average length to bottom width ratio may be greater than or equal to about 0.1:1、1:1、2:1、3:1、4:1、5:1、6:1、7:1、8:1、9:1、10:1、15:1、20:1、25:1、50:1、100:1、150:1、200:1、250:1、300:1、350:1、450:1、500:1、550:1、600:1、650:1、700:1、750:1、800:1、850:1、900:1、950:1, and/or less than or equal to about 1000:1、950:1、900:1、850:1、800:1、750:1、700:1、650:1、600:1、550:1、500:1、450:1、400:1、350:1、300:1、250:1、200:1、150:1、100:1、50:1、25:1、20:1、15:1、10:1、9:1、8:1、7:1、6:1、5:1、4:1、3:1、2:1 or 1:1.

In some embodiments, the dimples may be substantially circular. The circular depressions may have a diameter of about 0.05 to about 1.0 mm. For example, the average pit diameter may be greater than or equal to about 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1mm.

Various other shapes for the pits may also be included. By way of example only, such dimples may be triangular, pentagonal, hexagonal, heptagonal, octagonal, elliptical, ellipsoidal, and combinations thereof.

In some embodiments, the separator may have features of ribs, serrations, dimples, or combinations thereof. For example, the separator may have a series of zigzag ribs extending along the separator from top to bottom, and a second series of zigzag ribs extending horizontally along the separator. In other embodiments, the separator may have alternating serrated ribs, dimples, continuous, spaced or broken solid ribs, or a combination thereof.

Table 1 includes several specific embodiments of separators, which are presented by way of example only and not intended to be limiting, having serrations and/or dimples and various parameters that may be used to form such separators to prevent acid stratification and enhance acid mixing in flooded lead acid batteries (sometimes referred to as enhanced flooded batteries).

TABLE 1

The separators disclosed herein preferably provide enhanced electrolyte mixing and/or acid circulation compared to conventional separators. In certain embodiments, the separator provides less acid stratification as measured by electrolyte density at the top and bottom of the cell. The density difference may be less than 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 2.5%, or 1% after the battery cells have undergone 30, 60, or 90 start/stop events or cycles. In certain selected embodiments, the density difference may be less than 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 2.5%, or 1% after the cell remains stationary for 24, 48, or 72 hours.

In some embodiments, the improved separator may include a coating on one or both sides. Such coatings may include surfactants or other materials. In some embodiments, the coating may include one or more materials such as described in U.S. patent publication No. 2012/0094183, which is incorporated herein by reference. Such coatings may, for example, reduce the overcharge voltage of the battery system, thereby reducing gate corrosion and preventing drying and/or moisture loss, extending battery life.

The separators used in the various embodiments herein may incorporate one or more additives. This is because the additives may enhance the separator of certain vehicle stop/start flooded lead acid batteries. One such additive that may be present in the polyolefin is a surfactant, while another such additive may include one or more latex additives. Suitable surfactants include surfactants such as alkyl sulfates; alkyl aryl sulfonates; alkylphenol-alkylene oxide addition products; a soap; alkyl-naphthalene sulfonates; dialkyl esters of sulfosuccinates; a quaternary amine; block copolymers of ethylene oxide and propylene oxide; and salts of monoalkyl phosphates and dialkyl phosphates. The additives may be nonionic surfactants such as polyol fatty acid esters, polyethoxylated fatty alcohols, alkyl polysaccharides such as alkyl polyglycosides and mixtures thereof, amine ethoxylates, sorbitan fatty acid ester ethoxylates, organosiloxane-based surfactants, ethylene vinyl acetate terpolymers, ethoxylated alkylaryl phosphates, and sucrose esters of fatty acids.

In certain embodiments, the additive may be represented by the following compounds:

Formula (I) =r (OR ¹)_n(COOM^x+ _1/x)_m (I)

Wherein the method comprises the steps of

R is a non-aromatic hydrocarbon radical having from 10 to 4200 carbon atoms, preferably from 13 to 4200 carbon atoms, which may be interrupted by oxygen atoms,

R ¹ is H, - (CH ₂)_kCOOM^x+ _1/x or- (CH ₂)_k-SO₃M^X+ _1/X, preferably H, wherein k=1 or 2,

M is an alkali or alkaline earth metal ion, H ⁺ or NH ₄ ⁺, where not all variables M simultaneously have H ⁺ groups,

N=0 or 1,

M=0 or an integer from 10 to 1400, and

X=1 or 2, wherein the ratio of oxygen atoms to carbon atoms is in the range of 1:1.5 to 1:30, m and n cannot be 0at the same time. However, it is preferred that only one of the variables n and m is not equal to 0.

Non-aromatic hydrocarbon groups refer to groups that do not contain aromatic groups or which themselves represent one. The hydrocarbon group may be interrupted by an oxygen atom, i.e. contain one or more ether groups.

R is preferably a straight-chain or branched aliphatic hydrocarbon group which may be interrupted by oxygen atoms. Saturated, uncrosslinked hydrocarbon groups are very particularly preferred.

The additives of the compounds of formula (I) used to produce the various porous membranes described herein may also provide effective protection against oxidative damage to such separators. In some embodiments, porous membranes are preferred comprising an additive comprising a compound according to formula (I), wherein

R is a hydrocarbon radical having from 10 to 180, preferably from 12 to 75 and very particularly preferably from 14 to 40, carbon atoms which may be interrupted by from 1 to 60, preferably from 1 to 20 and very particularly preferably from 1 to 8, oxygen atoms, particularly preferably of the formula R ²-[(OC₂H₄)p(OC₃H₆) q-, where

O R ² is an alkyl radical having from 10 to 30 carbon atoms, preferably from 12 to 25, particularly preferably from 14 to 20,

O p is an integer from 0 to 30, preferably from 0 to 10, particularly preferably from 0 to 4, and

O q is an integer from 0 to 30, preferably from 0 to 10, particularly preferably from 0 to 4,

The sum of p and q in the particularly preferred compounds of o is from 0 to 10, in particular from 0 to 4,

N=1, and

·m＝0。

The formula R ²-[(OC₂H₄)_p(OC₃H₆)_q -is understood to also include compounds whose sequences of radicals in brackets differ from those shown. For example, compounds according to the invention in which the groups in brackets are formed by exchanging (OC ₂H₄) and (OC ₃H₆) groups are suitable.

Additives wherein R ² is a linear or branched alkyl group having from 10 to 20, preferably from 14 to 18 carbon atoms have proven particularly advantageous. OC ₂H₄ preferably represents OCH ₂CH₂,OC₃H₆ represents OCH (CH ₃)CH₂ and/or OCH ₂CH(CH₃).

As preferred additives, particularly preferred primary alcohols (p=q= 0;m =0) are proposed, preferably primary alcohols of fatty alcohol ethoxylates (p=1 to 4;q =0), fatty alcohol propoxylates (p= 0;q =1 to 4) and fatty alcohol alkoxylates (p=1 to 2;q =1 to 4). Fatty alcohol alkoxylates can be obtained, for example, by reaction of the corresponding alcohols with ethylene oxide or propylene oxide.

Additives of the m=0 type which are insoluble or poorly soluble in water and sulfuric acid have proven to be particularly advantageous.

Additives containing compounds of formula (I) are also preferred, wherein

R is an alkane radical having from 20 to 4200, preferably from 50 to 750 and very particularly preferably from 80 to 225, carbon atoms,

M is an alkali metal or alkaline earth metal ion, H+ or NH ⁴⁺, in particular an alkali metal ion such as Li ⁺、Na⁺ and K ⁺ or H ⁺, where not all variables M have simultaneously H ⁺ radicals,

·N＝0，

M is an integer from 10 to 1400, and

X is 1 or 2.

Among the suitable additives mentioned here are polyacrylic acids, polymethacrylic acids and acrylic acid-methacrylic acid copolymers in which the acid groups are at least partially (preferably 40%, particularly preferably 80%) neutralized. The percentages refer to the number of acid groups. Very particular preference is given to poly (meth) acrylic acid which is present entirely in salt form. Poly (meth) acrylic acid refers to polyacrylic acid, polymethacrylic acid and acrylic acid-methacrylic acid copolymers. Poly (meth) acrylic acid is preferred, in particular polyacrylic acid having an average molar mass Mw of from 1,000 to 100,000g/mol, particularly preferably from 1,000 to 15,000g/mol and very particularly preferably from 1,000 to 4,000 g/mol. The molecular weight of the poly (meth) acrylic acid polymers and copolymers was determined by measuring the viscosity of a 1% aqueous solution of the polymer neutralized with sodium hydroxide solution (Fikentscher constant).

Copolymers of (meth) acrylic acid are also suitable, particularly suitable copolymers include, in addition to (meth) acrylic acid, copolymers of 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 monomers are preferred, the percentages being based on the acid form of the monomer or polymer.

For neutralizing polyacrylic acid polymers and copolymers, alkali metal and alkaline earth metal hydroxides such as potassium hydroxide, in particular sodium hydroxide, are particularly suitable.

The porous membrane may be provided in various ways with one or more additives. For example, the additive may be applied to the polyolefin at the completion (i.e., after extraction) or added to a coating mixture used to produce the porous membrane. According to one possible preferred embodiment, the additive or the solution of the additive may be applied to the surface of the porous membrane or to the surface of the coating. This variant is particularly suitable for the use of non-thermostable additives and additives that are soluble in the solvent used for the subsequent extraction. Solvents which are particularly suitable as additives according to the invention are low molecular weight alcohols, such as methanol and ethanol, and mixtures of these alcohols with water. Application may occur on the side of the porous membrane facing the negative electrode, on the side facing the positive electrode, or on both sides. For embodiments in which the coating is present on only one side of the porous membrane, the additive may be applied to the coating, to the uncoated side of the coating or to both sides of the separator.

The additive may be present at a density of at least 0.5g/m²、1.0g/m²、1.5g/m²、2.0g/m²、2.5g/m²、3.0g/m²、3.5g/m²、4.0g/m²、4.5g/m²、5.0g/m²、5.5g/m²、6.0g/m²、6.5g/m²、7.0g/m²、7.5g/m²、8.0g/m²、8.5g/m²、9.0g/m²、9.5g/m² or 10.0g/m ². The additive may be present on the separator at 0.5-10g/m²、1.0-10.0g/m²、1.5-10.0g/m²、2.0-10.0g/m²、2.5-10.0g/m²、3.0-10.0g/m²、3.5-10.0g/m²、4.0-10.0g/m²、4.5-10.0g/m²、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/m²、5.0-10.5g/m²、5.0-11.0g/m²、5.0-12.0g/m² or a density in the range of 5.0-15.0g/m ².

This can be done by roll coating or impregnating the polyolefin in the additive or additive solution, followed by selective removal of the solvent (e.g. by drying). In this way, the application of the additive may be combined with, for example, extraction commonly used in the production of microporous polyolefin separator layers.

The photo examples of figures 1-7B next combine an acid electrolyte with an acid comprising a red dye to visually present an electrolyte with a higher acid density and lower pH level and distinguish it from a lower acid density and higher pH level.

Reference is now made to fig. 1. In fig. 1, a series of photographs comparing a battery cell with a serrated or stacked rib separator according to an exemplary embodiment (top row) with a battery cell with a conventional solid rib (which extends vertically along the separator) separator (down). The spacing between the stacked ribs (rib tip to rib tip) of the separator shown in the top row is about 11mm. Fig. 1 shows a side of a battery separator that generally faces a positive electrode in a flooded lead acid battery, such as a partially charged flooded lead acid battery. However, these ribs may alternatively face the negative electrode or may be included on both sides of the separator (e.g., may also be included on the side of the separator that is designed to face the negative electrode in a flooded lead acid battery). The cell shown in fig. 1 has undergone 90 start/stop events or cycles with the separator and encapsulated electrodes parallel to the direction of motion. As shown in fig. 1, cells with serrated rib separators showed significantly less acid stratification after 30, 60 and 90 start/stop cycles or events than cells with conventional separators.

Reference is now made to fig. 2. In fig. 2, a series of photographs comparing battery cells of the same type as shown in fig. 1 is shown. In a vehicle that travels 25 miles per hour, the battery cells go through 60 start/stop events or cycles and then rest overnight. The top row shows battery cells with serrated rib separators according to an exemplary embodiment, while the bottom row shows batteries with conventional solid rib conventional separators. As shown in fig. 2, the battery cells with the serrated rib separators exhibited significantly less acid stratification than the battery cells with conventional separators. Such tests validated laboratory findings shown in the photograph of fig. 1.

Turning now to fig. 3. In fig. 3, a battery cell having a narrower spaced serrated rib separator according to an exemplary embodiment (top row) is compared to a battery cell having a conventional solid ribbed separator (bottom row), wherein the solid ribs are perpendicular along the separator. The top row shows a separator with a spacing of about 7mm between the stack ribs. The battery cells underwent 90 start/stop events or cycles. As shown in fig. 3, cells with serrated rib separators showed significantly less acid stratification after 30, 60 and 90 start/stop cycles or events than cells with conventional separators.

Reference is now made to fig. 4. In fig. 4, a series of photographs depicts a comparison of a battery cell with a dimpled separator according to an exemplary embodiment (top row) with a battery cell with a conventional separator comprising a solid large rib and a solid small rib (bottom row), where such large and small solid ribs extend vertically along the separator. The battery cells underwent 90 start/stop events or cycles. As shown in fig. 4, cells with dimpled separators showed significantly less acid stratification after 30, 60, and 90 start/stop cycles or events than cells with conventional separators. Thus, solid ribs, such as shown in the bottom row of photographs in fig. 4, actually inhibit acid mixing of the separator within an idle start/stop lead acid battery.

Refer to fig. 5. In fig. 5, a series of photographs depicts a battery cell with a dimpled separator in accordance with an exemplary embodiment (top row) compared to a battery cell with a separator comprising a solid rib extending perpendicular along the separator in combination with a dimple (bottom row). The battery undergoes 90 start/stop events or cycles. As shown in fig. 5, the cells with the dimpled separator (top row) showed less acid stratification than the start/stop lead acid cells in the bottom row with separators comprising solid ribs in combination with dimples. However, some acid mixing is shown in the bottom row (e.g., as compared to the bottom row in fig. 1-4). For example, in some pictures of the bottom row, distinct areas or pockets of low density acid can be seen; however, acid mixing can also be seen. A bottom row of photographs demonstrates that a combination of serrations and solid ribs or a combination of dimples and solid ribs may prove effective in various batteries, systems and methods according to the present disclosure.

Reference is now made to fig. 6. In fig. 6, it includes a set of photographs comparing a battery cell having a dimpled separator (top row) according to an exemplary embodiment with a battery cell having a separator comprising solid ribs extending diagonally (at a small angle to the vertical of the separator) along the separator. The battery is subjected to 90 start/stop events or cycles. As shown in fig. 6, the cells with the dimpled separator (top row) showed less acid stratification than the start/stop lead acid cells in those photographs shown in the bottom row of fig. 1-4. Regarding the bottom row of photographs of fig. 6, it can be seen that some acid stratification still exists during 60 cycles or 60 start/stop events; however, acid stratification improved after 90 cycles.

Fig. 7A and 7B include photographs of a comparison of a conventional solid ribbed baffle (7A) and no baffle at all (7B) in a tank filled with 1.28 specific gravity acid (which is mixed). FIG. 7A includes a photograph of a conventional ribbed separator plate; acid stratification is indicated by the red acid concentration at the bottom of the tank and the clear liquid at the top of the tank. Fig. 7B includes a photograph with only lead gate electrodes therein without any separator; as indicated by the red color in the entire tank, much less acid stratification occurs. Fig. 7A and 7B help illustrate that conventional separators with solid ribs may prevent acid mixing and may promote acid stratification within start/stop flooded lead acid batteries. Likewise, FIG. 7B provides a baseline that does not include a spacer, with which each spacer may be compared and contrasted.

Fig. 8 includes photographs of battery cells constructed using serrated ribbed separators according to the invention prior to testing acid stratification.

Fig. 9 includes photographs of the battery cell of fig. 8 assembled within a housing for acid stratification testing. Lead tape is placed over the electrode and separator set. Once the acid is added to the housing, the acid level may be a few millimeters above these wire strips (in some cases, by way of example only, about 3mm above the wire strips). Since the housing containing the electrodes and separator is used to test acid stratification within the battery cell, in some embodiments, it may be preferable that the direction of movement of the test simulate starting/stopping movement of an electric vehicle. The run is thus essentially parallel to the plates and baffles of the photograph so that the acid moves over the surface of the electrodes when the vehicle starts, accelerates, decelerates and/or stops. Fig. 9 can also be seen as the top of the photograph facing the front bumper of an electric vehicle with start/stop capability, while the bottom of the photograph of fig. 9 faces the rear bumper of the same electric vehicle, while a bystander is looking down at a set of electrodes, separator plates, and lead strips, soon filling with acid for acid stratification testing. In other words, the electrodes and separator are parallel to the motion generated during the test.

Fig. 11 includes two views of a profile of a serrated separator used in accordance with various embodiments described herein.

Fig. 12 depicts a conductivity plot of sulfuric acid solution at 25 ℃. The graph is useful in understanding that acid stratification may result in uneven current flow due to conductivity differences in the high and low acid regions of the cell and/or battery.

Fig. 13 includes photographs of battery cells configured similarly to the battery cells depicted in fig. 6. However, for the battery cell depicted in fig. 13, in which the separator is inserted into the system perpendicular to the running direction of the vehicle (whereas for the battery cell shown in the figure, in fig. 6, the separator is inserted into the system parallel to the running direction, similar to the direction description of fig. 9 above). In various embodiments, it may be preferable that the separator be positioned parallel to the running direction of the vehicle and the battery system. This is because the photograph shown in fig. 13 shows that acid stratification is still occurring after 60 start/stop cycles or events, with no good acid mixing. With the top behavior example of fig. 13, acid stratification occurs and acid mixing is not optimal even though a dimpled separator is used therein according to various embodiments of the present invention.

Fig. 14 includes photographs of battery separators containing sawtooth ribs according to various embodiments described herein for enveloping electrodes to make start/stop automotive flooded lead acid batteries for testing, the results of which are described below.

15A-15D include diagrams of a plurality of serrated profiles of a separator according to various embodiments herein. Various optimized profiles for separators for improving and enhancing acid mixing are disclosed herein, and the diagrams set forth in fig. 15A-15D are merely examples of such optimized profiles. Many other optimized profiles fall within the scope of the separators, batteries, systems, and methods described herein.

Fig. 16 includes a chart depicting a cyclic test of one example of an enhanced flooded battery (or a flooded battery operating in an enhanced mode). In current newer battery applications, the enhanced flooded battery operates at a lower state of charge than previously known flooded lead acid batteries (which typically operate at an overcharged state or in excess of 100% state of charge). Thus, such enhanced flooded batteries may operate at less than 95% state of charge (SoC), in some cases less than 90%, in some cases less than 85%, in some cases less than 80%, in some cases less than 70%, in some cases less than 60%, in some cases less than 50%, in some cases less than 25%, in some cases even less than 10%. In this particular figure, a cycling test was performed on a battery having a depth of discharge (DoD) of 17.5%, and the separator used was a conventional ribbed separator, such as the one shown in the bottom row of photographs of fig. 1. The battery exhibits an ability to deliver energy under high cycle conditions in a high discharge state and is capable of functioning well in environments rich in lead sulfate. Batteries tested as in fig. 16 and used for start/stop applications have significantly improved energy flux compared to standard SLI batteries (e.g., batteries listed in standards such as EN 50342). Because such enhanced flooded batteries and/or flooded batteries for start/stop applications operate in a partially charged state, they need to have higher charge efficiency and/or need to be more receptive to charging. In some cases, enhanced flooded batteries use various additives in combination with one or more electrodes to increase the charge efficiency and/or to form a battery that is more receptive to charging. However, the reinforced separator described herein may achieve the same objective.

The separators, methods, batteries, and battery systems described herein can provide improved electrolyte circulation and mixing with less acid stratification over time. This is particularly important for deep cycle and/or enhanced flooded lead acid batteries, where acid stratification can significantly reduce battery performance. Various flooded lead acid batteries, enhanced flooded lead acid batteries, and applications thereof may benefit from the improved separators, methods, batteries, and systems described herein. Various start/stop vehicles, including but not limited to various electric vehicles, automobiles, hybrid vehicles, forklifts, golf carts, community electric vehicles, etc., may benefit from the improved separators, batteries, battery systems, and methods described herein, particularly vehicles and/or batteries that are not fully charged and are in a partially charged state.

The exemplary embodiments of the enhanced flooded separators described herein, which may be referred to as acid-mixing separators, may be used in enhanced flooded batteries, particularly in sports batteries, and surprisingly and unexpectedly provide enhanced flooded batteries with significantly improved acid mixing and/or acid circulation, thereby significantly reducing or completely preventing acid stratification within the enhanced flooded batteries. This may be very important because the flow and circulation of acid along the entire separator means that the entire cell is being used, rather than some smaller portion of the cell being used. That is, using the enhanced separator, battery, system, and method of the present disclosure, the electrolyte (e.g., sulfuric acid) is free to flow to and along all or nearly all portions of the separator, and thus free to flow to and along all or nearly all portions of the positive and negative electrode active materials on the electrode. In contrast, for acid stratification (see, for example only, the acid stratification present in the bottom row of photographs of fig. 1-4, wherein a red indicator has been added to the acid such that the acid is clearly visible and is present in the lower half of these test cells, the clear liquid, i.e., water, which is clearly visible and is present near the upper half of those test cells), the entire portion of the separator, and thus the positive and negative active materials of the entire portion on either side of such separator, is completely devoid of acid and thus is not fully utilized to provide the maximum potential for power to potential devices/vehicles using the cells. Accordingly, the improved separators, batteries, systems, and methods described herein greatly reduce acid stratification in flooded lead acid batteries (e.g., enhanced flooded batteries).

The cause of the acid stratification is the non-uniformity of the current density generated on the surfaces of the positive and negative plates or electrodes. The graph shown in fig. 12 illustrates the relationship of H ₂SO₄ conductivity to the weight percent sulfuric acid concentration.

In some preferred embodiments of the invention, the serrations, dimples and/or broken ribs present on one or more surfaces of the separator are unevenly distributed. Additionally, in some preferred embodiments, the serrations, dimples, and/or broken ribs present on one or more surfaces of the separator are different in certain areas or regions on at least one side of the separator. For example, the serrations and pits themselves may be non-uniform in size (e.g., may be randomly sized), and the spacing between serrations and/or pits may be random and/or non-uniform. For example, the various serrations and/or dimples used herein may be present in an ordered or disordered array on one or both surfaces of the separator. In addition, various ribs such as serrated ribs as used herein may be non-linear. For example, some of the serrated ribs may be in a wavy form or a nonlinear form.

In various embodiments, when the separator is positioned within an enhanced flooded battery, the enhancement of the separator is parallel to the direction of travel of the battery, exhibiting the effects of an enhanced flooded separator for the enhanced flooded batteries described herein. This effect can be seen by comparing the ideal results of fig. 6 with the non-ideal results of fig. 13. In the photograph of fig. 13, acid stratification was still observed even with the separator with enhanced acid mixing profile. This is because the battery cell in fig. 13 is placed such that the reinforcement on the separator and the electrode is perpendicular to the running direction in which the battery travels in the vehicle. Placing the battery in the vehicle, with the electrodes and separator parallel to the start and stop inertias, will likely in some cases allow better mixing of the acids than perpendicular placement.

The various reinforcing separators described herein, such as separators having serrations for improved acid mixing and acid circulation, may have different spacing and/or different forms. 15A-15D illustrate examples of serrated ribs that may be useful in the present invention. Such forms and others (uniform and non-uniform, and ordered and disordered) may allow for improved CCA (cold start amperage) within flooded lead acid batteries as well as other key improvements in battery electrical performance. In the zigzag form as shown in fig. 15A to 15D (by way of example only), the surface area is reduced by about 53% compared to a separator with solid ribs (control), allowing the ribs to contact less PAM (positive electrode active material) resulting in an improvement in CCA performance. In forms similar to those shown in fig. 15A-15D, rib mass can be reduced by 33% compared to solid rib profile (control), allowing for more acid availability and improved performance. In addition, balancing rib mass and open cell to maintain PAM (positive electrode active material) compression may be important for acid mixing and usability.

Furthermore, the arrangement and design of the protrusions (such as dimples, serrations, etc.) is preferably optimized for compression to prevent PAM from falling off and is preferably supported on the gate frame so as not to push particles away from intimate contact with the positive gate frame or current collector.

The battery of the present invention can save costs and requires less lead for excellent performance due to the improvement of PAM utilization. Thus, the cost of the battery, which is a need of the automobile manufacturer, can be reduced, and the weight of the battery, which is also a need of the automobile manufacturer, can be reduced.

In some cases, the reinforced separators used in the present invention may have an optimized profile having a rib surface area that is 10-90% of the surface area of a conventional rib, preferably 30-70% of the surface area of a conventional rib, and more preferably, in some cases, 40-60% of the surface area of a conventional rib, as compared to the rib surface area of a conventional rib profile, such as a solid vertical rib profile. All of these depend on rib geometry, rib spacing, and the ultimate goal of improving acid mixing and preventing acid stratification, all of which have been optimized.

Examples

Fig. 8 and 9 show battery experiments performed in a battery cell container. The battery test cells shown in these photographs have a white housing and a set of lead electrodes with the following general attributes:

TABLE 2

In other examples shown below, the commercially available panel 31, 19 panels/panel Ca/Ca extended the battery test data. In this table, the separator labeled "new" has the serrated profile shown in the envelope of fig. 14, while the result labeled "control" has solid ribs perpendicular along the separator. These results demonstrate unexpected and/or surprising findings regarding the improvement in battery performance of start/stop enhanced flooded lead acid batteries using enhanced separators in accordance with the invention. It is noted that even when the battery in the vehicle is not moved greatly, but is only in a general operation, the results thereof are still improved as shown in the following table when the test is performed while moving from one place to another place within the factory. Thus, in combination with energy from the operation of the vehicle and/or from various start/stop events, battery performance results may be more significantly improved.

TABLE 3 Table 3

18A-32B, a battery cell in a short battery such as used in an ISS, SLI, or golf car battery is depicted. The CFD examples discussed in fig. 35-37 and 39 depict battery cells in a high battery, such as a battery for the power industry, such as a forklift battery.

An example of a short cell depicts a separator having a width of about 142mm, a height of about 129mm, a back web thickness of about 250 μm, and a rib height of about 600 μm. The short cell example also depicts a headspace of about 3mm between either lateral edge of the separator and the sidewall boundary of the cell housing, about 44mm above the separator.

An example of a high cell depicts a separator having a width of about 158mm, a height of about 406mm, a back web thickness of about 500 μm and a rib height of about 1.8 mm. The high cell example also depicts a headspace of about 3mm between either lateral edge of the separator and the sidewall boundary of the cell housing and about 51mm above the separator.

The importance of this Midtronic CCA test is that it is not a global standard test, but rather a handheld device that uses an algorithm to quickly and easily calculate battery performance. Using an acid-mixing separator, an increase in the surface area of the positive gate electrode exposed to acid allows for improved conductance and improved electrode performance. Although not an industry standard, its simplicity and ease of use are considered by purchasing decisions around the world today. Improving the performance of the algorithm tester is critical to customer satisfaction and the improvement in the acid mixing baffle contributes to this result, as shown in table 3.

The following examples describe in detail the analysis of exemplary separators and batteries using Computational Fluid Dynamics (CFD) to quantify the efficacy of reversing, reducing, or completely eliminating acid stratification within a lead acid battery or flooded lead acid battery, or an enhanced rechargeable battery, or an idle start/stop rechargeable battery, of exemplary embodiments disclosed herein. The model typically begins with complete stratification, with the highest concentration of acid in the lower portion of the cell and water in the upper portion of the cell with an interface therebetween.

A sinusoidal graphical representation of lateral motion is depicted in fig. 17A. This movement can be described as moving the diaphragm and/or battery from a starting position in one direction to a positive 1 foot displacement, reversing the direction to return the modeled diaphragm and/or battery to and past the starting position to a negative 1 foot displacement, the reversing direction bringing the model back to the starting position. The above action takes place within 1 second. This pattern of motion is used in all CFD models that simulate horizontal lateral or horizontal sideways motion and repeated as many times as necessary to perform the analysis of the required amount of time. The CFD analysis described herein utilizes lateral or sideways motion in a direction parallel to the flat knitting machine of the exemplary separator. In other words, the movement is horizontal and in a direction parallel to the major plane of the example spacer.

Furthermore, analysis of the CFD model resulted in a volume uniformity index of the acid volume fraction throughout the liquid electrolyteWherein a perfectly mixed electrolyte would have a uniformity index of 1.0. This value is calculated using the following equation 1:

Wherein,

Is/>Is a volume average value of (2);

Is the value of the selected scalar in the battery cell; and

V _C is the cell capacity.

Fig. 17B shows a comparison of one solid rib spacer and one serrated rib spacer, each undergoing the motion defined in fig. 17A, and analyzed using CFD. Both separators analyzed were positive containment separators, meaning that the separator surrounded the positive electrode plate with its solid or serrated (and also broken as described below) ribs facing the positive electrode plate.

Fig. 18A shows lateral movement of the positive-enveloping solid rib separator over 60 seconds, and CFD analysis was used to show the mixing of layered electrolytes of a flooded lead acid battery. It can be seen that there is little mixing at the outer perimeter of the separator, but very little, nearly no, mixing between the solid ribs. Fig. 18B depicts the volume uniformity of the analysis and reveals that lateral motion mixing can increase the volume uniformity by 7%.

Fig. 19A shows lateral movement of the positive enveloping serrated rib separator over 60 seconds and CFD analysis was used to show the mixing of the layered electrolyte of the flooded lead acid battery. It can be seen that there is some amount of mixing at the outer periphery of the baffle, with increased mixing between the internal serrated ribs. Fig. 19B depicts the volume uniformity of the analysis and reveals that lateral motion mixing increases the volume uniformity by 12%.

Fig. 20A is a side-by-side comparison of CFD mixing results for the baffles shown in fig. 18A and 19A. Fig. 20B shows that positive encapsulation of the serrated rib separator increased the mixing uniformity by 5% as compared to positive encapsulation of the solid rib separator.

FIG. 21 defines a rocking motion used in CFD analysis of a positive enveloping serrated rib baffle. FIG. 22 shows a graphical representation of CFD analysis of a serrated rib baffle undergoing the rocking motion described in FIG. 21.

Fig. 23 is a schematic view of a separator containing or enveloping the negative electrode plate (negative envelope) of a flooded lead acid battery with solid or serrated (and broken as described below) ribs facing the positive electrode plate.

FIG. 24A is a graphical representation of a CFD analysis of a negative enveloped serrated rib baffle undergoing lateral movement and further compared to a graphical representation of a CFD analysis of a positive enveloped serrated rib baffle undergoing the same lateral movement. FIG. 24B is a graphical representation of the volume uniformity of the negative enveloping serrated rib separator of FIG. 24A, showing a 22% change in volume uniformity from onset of stratification to 60 seconds of mixing. Fig. 24C is a graphical comparison of the volume uniformity of negative and positive-packed serrated rib separators, which demonstrates a 10% increase in mixing of the negative-packed separator over the positive-packed separator.

Referring now to fig. 25A-25F, several exemplary embodiments describe a rib-break arrangement employing variables defining various rib-break forms for use in CFD analysis. 26A-26G illustrate a battery separator with broken ribs according to an exemplary embodiment of the present disclosure and as defined in the diagrams of FIGS. 26A-26G. An exemplary battery separator is shown in fig. 26A-26G; further, the example battery separators disclosed herein may have any number of columns 2606 ¹–2006ⁿ.

FIG. 27A is a graphical comparison of CFD analysis of negative encapsulated serrated rib and negative encapsulated broken rib baffles (as shown in FIG. 26D) with substantially lateral or horizontal movement. Fig. 27B depicts a comparison of the volumetric uniformity of several CFD analyses of a previously described separator plate undergoing lateral movement. The negative envelope split-fin separator produced a 26% increase in mixing at 60 seconds as compared to the negative envelope serrated fin separator.

Referring now to fig. 28A, a graphical comparison of CFD analysis of a negative encapsulated solid rib separator and a negative encapsulated broken rib separator (as shown in fig. 26D) undergoing a substantially lateral or horizontal motion as shown. Fig. 28B depicts a comparison of the volumetric uniformity of several CFD analyses of the previously described baffles undergoing substantial lateral or horizontal movement. The negative envelope rib-breaking separator produced a 28% increase in mixing over a period of 60 seconds.

Fig. 29A shows in detail a separator having three regions in the form of different broken ribs, wherein the regions vary in the transverse direction along the direction of the flat knitting machine of the separator. It should be noted that these areas may also be distributed in the machine direction of the separator or in both the machine and cross-machine directions of the separator. It is further recognized that there may be any number of regions in either or both directions. Furthermore, the edges of the separator plates themselves may be their own regions, so that for better results the edges are optimized to have a pronounced design and/or ribbed form and/or broken ribbed form, etc. In certain preferred embodiments herein, the regions of the separator (for a multi-region separator) are formed such that the mass of the form in each region is relatively uniform and/or such that the formed separator functions well on the cell forming equipment and/or the cell is formed faster because of the efficiency of acid filling.

Fig. 29B depicts a split rib form variation of a partition panel. The subscript numerals "1" and "2" relate to two different rib-breaking forms. In certain embodiments, regions 1 and 3 (subscript "1") contain the same pattern, such as a broken rib pattern, and region 2 (subscript "2") has, for example, a broken rib pattern that is different from regions 1 and 3. Fig. 29C depicts the rib breaking variable of a single-zone rib-breaking separator.

FIGS. 30A-30H depict a variation of a three-segmented, rib-type separator.

Fig. 32A is a graphical comparison of CFD analysis of a negative-packed three-zone rib-shaped separator and a negative-packed single-zone rib-shaped separator (as shown in fig. 26D) undergoing lateral movement. FIG. 32B depicts a comparison of the volumetric uniformity of acid fractions of several CFD analyses of the previously described separator undergoing lateral movement; in this figure, the tri-partition plate showed a 1% increase in mixing compared to the single-partition plate.

33A-33C illustrate the head space of a battery having a splash shield, according to an exemplary embodiment of the present disclosure. These splash baffles may be used with any of the example baffles described herein. In these embodiments, the headspace of each cell is optimized to better utilize the work or energy (horizontal and vertical energy) of moving or shaking electrolyte and/or acid waves or fluctuations to further increase the volumetric uniformity of acid mixing and acid components along all parts of the electrode plates, both throughout the lead acid cell and within the cell, to approach or even reach a volumetric uniformity of 1.0 (complete mixing). The splash guard may be formed or mounted to a cover or inner wall of the battery housing, or may take the form of a device clamped to the electrode strip. The splash shield may further have a flat surface, a curved convex or concave shape, a concave-convex shape, a sharp or rounded edge, or any other shape. Additionally, the electrode strips may be designed or moved to better mate with a splash shield or any other splash and/or movement that the electrolyte may experience during cell movement. The splash shield may also float on the electrode or contain one or more pivots to optimize the effect of any splashing and/or movement that the electrolyte may experience during cell movement.

In addition, the cell design may change to help facilitate acid separation. One such example may include mounting the battery on a resilient mount such as a spring or rubber or other viscoelastic material to allow the battery to continue to move or rock after the speed changes. The cell housing can be made higher and more electrolyte added to increase the head pressure of the overall electrolyte supply within the cell. The battery can also be designed as a horizontal cylinder or ellipsoid, or even as a sphere. In addition, the cover can be designed as a dome.

34A-34I illustrate various details of exemplary embodiments of the present disclosure.

Fig. 35 depicts a separator for a high cell having a rib form substantially as shown in fig. 26D. Fig. 36 depicts the volumetric uniformity over time as a result of CFD analysis of the separator depicted in fig. 35 as compared to other separator designs. As shown in fig. 17A, the test cell was simulated as being subjected to lateral movement with the separator parallel to the direction of movement for 60 seconds. The thin bottom line represents a short separator plate with a solid rib form and the thick bottom line represents a high separator plate with a solid rib design. The thin top line represents a short separator with a preferred form of broken ribs and the thick top line represents a tall separator with a preferred form of broken ribs. It can be seen that the short separator plate with solid rib form showed a 13% increase in volume uniformity compared to the high separator plate with solid rib form, which increased the volume uniformity by only 7%. Short baffles with the preferred form of broken ribs showed a 28% increase in volume uniformity. High baffles with the preferred form of broken ribs showed a 62% increase in volume uniformity over 60 seconds of lateral movement. This is the maximum amplification of the test batch.

Fig. 38 depicts an exemplary separator of the present invention in the form of a broken rib that may be placed, for example, between a flat separator and an electrode. It can be seen that the broken rib is secured by a network of elongate stringers. The stringers are shown arranged vertically and horizontally, however it will be appreciated that other angles may be incorporated.

39A-39C illustrate exemplary embodiments depicting dimensional values of power separator profiles, spacing, and head space in, for example, a high battery or battery housing.

In addition, the cell design may be altered to help facilitate acid separation. One such example may include mounting the battery on a resilient mount such as a spring or rubber or other viscoelastic material to allow the battery to continue to move or rock after the speed changes. The cell housing can be made higher and more electrolyte added to increase the head pressure of the overall electrolyte supply within the cell. The battery can also be designed as a horizontal cylinder or ellipsoid, or even as a sphere. In addition, the cover can be designed as a dome.

The baffles described herein may further be used in combination with other devices for acid stratification prevention/reversal (e.g., weir devices, dip tubes, acid pumps or bubblers, displacement devices, or any combination thereof).

A number of such devices are disclosed below: U.S. patent application publication No. 2012/0214032 to Franklin et al, no. 2004/0067410 to Jones, no. 2003/0148170 to Jones, and U.S. patent No. 6,274,263 to Jones, no. 4,629,622 to Yonezu et al and No. 4,565,748 to Dahl; all of which are incorporated herein by reference. The separator may be provided in the form of a page, envelope or full sleeve/sleeve. The separator may further be provided with full-side curls/seals or spaced curls/seals and may even provide openings at the bottom folds of the folded separator.

It will be appreciated that any of the rib forms described herein may have a spacing between columns to allow gas to rise during an overcharge event. Furthermore, if the separator is folded to form an envelope, the rib-breaking pattern may not have a space in the longitudinal direction (machine direction) between the rows of the rib-breaking pattern to provide strength. In addition, the rib-broken separator may be further embossed. It is further recognized that any rib form or other protrusion may be provided on any interior surface of the battery housing or any surface on either or both of the positive and negative electrodes. For a battery placed in a vehicle, the preferred embodiment may place the separator in a direction generally parallel to the motion of the vehicle in order to utilize the starting and stopping motion of the vehicle.

It is believed that the improved separators described herein, such as the split-rib separators described herein, may further help prevent the formation of sulfated crystals, and may also help provide more uniform heat distribution and/or heat mixing and/or heat dissipation (dissipating heat in less time than known separators, such as solid rib separators for liquid lead acid batteries). It is also believed that the example rib-breaking separators described herein may also provide improved or faster or more efficient filling of lead acid batteries, gel batteries, and/or enhanced flooded batteries.

In various embodiments of the present disclosure, the disclosed separators provide reduced acid stratification, or even completely eliminate acid stratification, such that the mixing level or volume uniformity of acid or electrolyte within a flooded lead acid battery is 1.0 or near 1.0. In various embodiments, the separators disclosed herein are also low resistance (ER) separators. In such embodiments, the separator may include improvements, such as improved fillers that 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 high structural morphology and/or reduced particle size and/or a different amount of silanol groups and/or is more hydroxylated than previously known fillers. The improved filler may absorb more oil and/or may allow for the incorporation of greater amounts of process oil during separator formation without simultaneous shrinkage or compression when the oil is removed after extrusion. For example, silica having an intrinsic oil absorption value of about 175-350ml/100g, in some embodiments 200-350ml/100g, in some embodiments 250-350ml/100g, and in other embodiments 260-320ml/100g, is used to form the improved separator, although other oil absorption values are also possible.

The filler may further reduce so-called hydration spheres of electrolyte ions, enhancing their transport through the membrane, thereby again reducing the overall resistance or ER of the cell (e.g., enhanced flooded cell or system).

The one or more fillers may include various substances (e.g., polar substances such as metals) that promote the flow of electrolyte and ions through the separator. Such separators are used in rechargeable batteries, such as enhanced flooded batteries, and also result in a decrease in overall resistance.

The low ER microporous separator of the present invention may also include a novel and improved pore morphology and/or a novel and improved fibril morphology such that when such separator is used in a flooded lead acid battery, the separator contributes to a significant reduction in resistance in the flooded lead acid battery. This modified pore morphology and/or fibril morphology may result in a separator whose pores and/or fibrils approximate the roast string (shish-kebab or shish kabob) type morphology. Another way to describe new and improved pore shapes and structures is to texture fibril morphology, wherein silica nodes or nodes of silica are present on a barbecue string type structure on polymer fibrils (fibrils, sometimes referred to as shish) within a battery separator. In addition, in certain embodiments, the silica structure and pore structure of the separator according to the present invention may be described as a skeletal structure or a spinal structure or spinal structure, wherein the silica nodes on the polymer string along the polymer fibrils look like vertebrae or discs ("kebabs") and are sometimes substantially perpendicular to the elongated central spinal column or fibrils (extended chain polymer crystals), which approximate a spinal shape ("shish").

In some cases, an improved battery comprising an improved separator having improved pore morphology and/or fibril morphology may exhibit a 20%, in some cases 25%, in some cases 30%, and in some cases even more than 30% drop in electrical impedance ("ER") that may reduce the internal resistance of the battery, while such a separator maintains and maintains a balance of other critical, desirable mechanical properties of a lead acid battery separator. Furthermore, in certain embodiments, the separators described herein have new and/or improved pore shapes such that more electrolyte flows through or fills the pores and/or voids than known separators. The ultra-high molecular weight polyethylene in the separator may comprise a polymer of a barbecue string (shish-kebab) configuration comprising a plurality of extended chain crystals (shish configuration) and a plurality of folded chain crystals (barbecue string configuration), wherein the barbecue string constitutes an average repetition or period of 1nm to 150nm, preferably 10nm to 120nm, and more preferably 20nm to 100nm (at least on a portion of the side of the separator having ribs). In certain of these low ER embodiments of the present separator, the separator for a lead acid battery described herein comprises a filler selected from the group consisting of silica, precipitated silica, fumed silica, and precipitated amorphous silica; wherein the molecular ratio of OH to Si groups within the filler is in the range of 21:100 to 35:100, in some embodiments in the range of 23:100 to 31:100, in some embodiments 25:100 to 29:100, and in certain preferred embodiments 27:100 or higher, as measured by 29 Si-NMR.

In certain alternative embodiments, the disclosed separator exhibits a reduced electrical resistance, e.g., an electrical resistance of no greater than about 200mΩ.cm²、180mΩ.cm²、160mΩ.cm²、140mΩ.cm²、120mΩ.cm²、100mΩ.cm²、80mΩ.cm²、60mΩ.cm²、50mΩ.cm²、40mΩ.cm²、30mΩ.cm² or 20mΩ.cm ². In various embodiments, the separators described herein exhibit an ER reduction of about 20% or more as compared to known separators of the same thickness. For example, a known separator may have an ER value of 60mΩ.cm ²; thus, a separator according to the invention of the same thickness will have an ER value of less than about 48mΩ.cm ². The separators described herein with low ER may have any or all of the features set forth in U.S. provisional patent application No.62/319,959 owned by Daramic, LLC and filed on 8/4 of 2016, which provisional application is incorporated herein by reference in its entirety.

In accordance with at least selected embodiments, the present disclosure relates to improved lead acid batteries, such as flooded lead acid batteries, improved systems including lead acid batteries, and/or battery separators, improved vehicles including such systems, methods of manufacture or use, or combinations thereof. In accordance with at least some embodiments, the present disclosure relates to improved flooded lead acid batteries, improved battery separators for such batteries, and/or methods of making, testing, or using such improved flooded lead acid batteries, or combinations thereof. Additionally, disclosed herein are methods, systems, batteries, and/or battery separators for use in flooded lead acid batteries that reduce acid stratification, improve battery life and performance.

Exemplary separators as disclosed herein may preferably be characterized by having or providing improved electrical conductance over time. The conductance may be determined as a cold start amps (CCA), for example measured in a Midtronics tester. For example, a lead acid battery equipped with a separator of the present invention may exhibit a CCA reduction of less than 10%, less than 9%, less than 8%, less than 7%, less than 6%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, or less than 0.5% over a period of 30 days as measured by a Midtronics tester.

Preferably, the separator of the present invention comprises a porous membrane (e.g., a microporous membrane having a pore size of less than about 1 micron, a mesoporous or macroporous membrane having a pore size of greater than about 1 micron) made of a natural or synthetic material such as polyolefin, polyethylene, polypropylene, phenolic resin, PVC, rubber, synthetic Wood Pulp (SWP), glass fibers, cellulose fibers, or combinations thereof, more preferably a microporous membrane made of a thermoplastic polymer. Preferred microporous membranes can have a pore diameter of about 0.1 microns (100 nanometers) and a porosity of about 60%. In principle, the thermoplastic polymer may comprise all acid resistant thermoplastic materials suitable for use in lead acid batteries. Preferred thermoplastic polymers include polyethylene and polyolefin. Polyvinyl materials include, for example, polyvinyl chloride (PVC). Polyolefins include, for example, polyethylene, such as Ultra High Molecular Weight Polyethylene (UHMWPE), and polypropylene. A preferred embodiment may comprise a mixture of filler (e.g. silica) and UHMWPE.

The porous film layer may comprise a polyolefin, such as polypropylene, an ethylene-butene copolymer, preferably polyethylene, more preferably a high molecular weight polyethylene (e.g., a polyethylene having a molecular weight of at least 600,000), even more preferably an ultra high molecular weight polyethylene (e.g., a polyethylene having a molecular weight of at least 1,000,000, particularly exceeding 4,000,000, and most preferably from 5,000,000 to 8,000,000 (as measured by a viscometry and calculated by the Margolie equation), a standard load melt index of substantially 0 (as measured using standard load 2,160g as described in ASTM D1238 (condition E)) and a viscosity number of not less than 600ml/g, preferably not less than 1,000ml/g, more preferably not less than 2,000ml/g, and most preferably not less than 3,000ml/g (as measured at 130 ℃ in a solution of 0.02g polyolefin in 100g decalin naphthalene).

According to at least one embodiment, the porous membrane may comprise Ultra High Molecular Weight Polyethylene (UHMWPE) mixed with a processing oil and precipitated silica. According to at least one embodiment, the microporous membrane may comprise Ultra High Molecular Weight Polyethylene (UHMWPE) mixed with processing oil, additives, and precipitated silica. The mixture may also include minor amounts of other additives or agents (e.g., wetting agents, colorants, antistatic additives, etc.) common in the separator art. In some cases, the microporous polymer layer may be a homogeneous mixture of 8 to 100 volume percent polyolefin, 0 to 40 volume percent plasticizer, and 0 to 92 volume percent inert filler material. The filler may be a dry, finely divided silica. The preferred plasticizer is petroleum oil. Since the plasticizer is the component most easily removed from the polymer-filler-plasticizer composition, it can be used to impart porosity to the battery separator.

In some embodiments, the porous film may be prepared by mixing about 30 wt% silica with about 10 wt% UHMWPE and about 60% process oil in an extruder. Microporous films can be formed by passing the composition through a heated extruder, passing the extrudate produced by the extruder through a die and into a nip formed by two heated calender rolls to form a continuous web, extracting a large amount of process oil from the web with a solvent, drying the extracted web, cutting the web into channels of a predetermined width, and rolling the channels into rolls. The calender roll may be engraved with various groove forms to impart ribs, serrations, embossments, etc. to the film. Alternatively or additionally, ribs or the like may be imparted to the porous film by passing the extruded film through additional suitable grooved calender rolls or presses.

The additive, surfactant, agent, filler, or additives may be added to the porous membrane in various ways. For example, one or more additives may be added to the microporous membrane (when it is complete, e.g., after extraction), and/or to the mixture used to produce the membrane. According to a preferred embodiment, the additive or a solution of the additive is applied to the surface of the porous membrane. This variant is particularly suitable for applications of non-thermostable additives and additives that are soluble in solvents used for subsequent extraction. Solvents which are particularly suitable as additives according to the invention are low molecular weight alcohols, such as methanol and ethanol, and mixtures of these alcohols with water. The application may be on the side of the microporous membrane facing the negative electrode, the side facing the positive electrode, or both sides.

The microporous membrane may also be prepared by immersing the microporous membrane in the additive or additive solution, followed by optional removal of the solvent, for example by drying. In this way, the application of the additive may be combined with, for example, extraction, which is often applied during the production of the separator.

Another preferred option is to mix one or more additives into the mixture of thermoplastic polymer and optional filler and other additives used to make the porous membrane. The homogeneous mixture containing the additive is then formed into a web material.

The separator of the present invention may be a low ER separator, a low moisture loss separator, and/or may have at least a portion including protrusions, broken ribs, serrated ribs, discontinuous ribs, etc. (non-solid ribs) to improve acid mixing or conduction of the separator. The protrusions include features such as short rib segments, bumps (nub), embossments, and the like. The protrusions may be located on either or both sides of the separator. Typically, the protrusions will be located at least on the side facing the positive plate (positive active material or PAM). The protrusions may be arranged in rows, with the protrusions in each row being spaced apart from each other and from the protrusions in an adjacent row. In some cases, the protrusions may be located on the side of the separator facing the positive electrode active material, on the side of the separator facing the negative electrode active material (or NAM), or on both sides of the separator.

In some embodiments of the invention, the protrusions are ribs having a height of at least about 0.005mm、0.01mm、0.025mm、0.05mm、0.075mm、0.1mm、0.2mm、0.3mm、0.4mm、0.5mm、0.6mm、0.7mm、0.8mm、0.9mm、1.0mm、1.1mm、1.2mm、1.3mm、1.4mm or 1.5 mm.

In some embodiments of the invention, the protrusions are short length ribs having a rib width of at least about 0.005mm、0.01mm、0.025mm、0.05mm、0.075mm、0.1mm、0.2mm、0.3mm、0.4mm、0.5mm、0.6mm、0.7mm、0.8mm、0.9mm、1.0mm、1.1mm、1.2mm、1.3mm、1.4mm or 1.5 mm. The ribs may have a width of about 0.005-1.5mm,0.01-1.0mm,0.025-1.0mm,0.05-1.0mm,0.075-1.0mm,0.1-1.0mm,0.2-1.0mm,0.3-1.0mm,0.4-1.5mm, 1.0mm,0.5-1.0mm,0.4-0.8mm, or 0.4-0.6 mm.

The separator may include negative longitudinal or intersecting ribs or mini-ribs, such as negative ribs having a height of about 25 to 250 microns, possibly preferably about 50 to 125 microns, more preferably about 75 microns.

In certain embodiments, the protrusions may include ribs, wherein each rib has a longitudinal axis disposed at an angle of 0 ° to less than 180 ° relative to the top edge of the baffle. In some cases, all of the ribs in the separator may be disposed at the same angle, while in other embodiments, the ribs may be disposed at different angles. For example, in some embodiments, the separator may include rows of ribs, with at least some of the rows having ribs at an angle α relative to the top edge of the separator. All of the ribs in a single row may have the same approximate angle, but in other cases, ribs of different angles may be included in a single row.

In some cases, one entire face of the separator plate will contain multiple rows of protrusions, while in other embodiments, some segments of the separator plate surface will not include protrusions. These segments may occur along any edge of the separator including the top, bottom or sides, or may occur toward the middle of the separator, with the segments being surrounded on one or more sides by portions having protrusions.

In certain possible preferred embodiments with broken ribs (see fig. 1), the section will contain at least two sets of rows, wherein the ribs in the first row are arranged at an angle of 0 ° to less than 180 °, and the ribs in the second row are arranged at an angle of from 0 ° to less than 180 °, which may be the same or different from the angle of the ribs in the first set of rows. Fig. 40 includes an illustration of a spacer (100) having a top edge (101) with multiple sets of first (102) and second (103) rows.

In certain other possibly preferred embodiments (see fig. 41), the second portion will comprise at least two sets of rows, wherein the ribs in the first row are disposed at an angle of 0 ° to less than 180 °, and the ribs in the second row are disposed at an angle of 0 ° to less than 180 °, which may be the same or different from the angle of the ribs in the first set. Fig. 41 includes an illustration of a baffle (400) having a top edge (401) with a central first portion (402) and an outer second (403) portion.

In some cases, the second portion will include a fifth set of rows with ribs, designated herein as R ⁵ (404), having an angle θ ⁵ (405) relative to the top edge of the back web, where θ ⁵ is from 0 ° to 90 °, from 30 ° to 85 °, from 45 ° to 85 °, from 60 ° to 80 °, or from 60 ° to 75 °. The preferred value for θ ⁵ is 90 °. The portion may include a sixth set of rows, denoted herein as R ⁶ (406), having an angle θ ⁶ (407) with ribs having an angle θ ⁶ relative to the top edge of the back web, where θ ⁶ ranges from 90 ° to less than 180 °, 95 ° to 150 °, 95 ° to 120 °, 100 ° to 120 °, or 105 ° to 120 °. The first preferred value for θ ⁶ is 90 °. The ribs in different rows may be the same (as shown at 400) or different sizes. The distance between adjacent rows may be from-5 to 5mm, where a negative number indicates the degree of row overlap. The distance may be measured from center rib to center rib.

When there are different rows, the rows may appear in a repeating pattern. (400) The simplest repeating pattern-R ⁵-R⁶ -can be seen. Other modes include -R⁵-R⁵-R⁶-;-R⁵-R⁵-R⁵-R^6-;-R⁵-R⁵-R⁶-R⁶-;-R⁵-R⁵-R⁵-R⁵-R⁶-;-R⁶-R⁵-R⁵-R⁵-R⁶-;-R⁵-R⁵-R⁵-R⁶-R⁶-;, and so on.

In some selected embodiments, the porous separator may have negative longitudinal or transverse ribs as protrusions on opposite sides of the membrane. The negative or rear rib may be parallel to the top edge of the separator plate or may be placed at an angle thereto. For example, the intersecting ribs may be about 90 °, 80 °, 75 °, 60 °, 50 °, 45 °, 35 °,25 °,15 °, or 5 ° relative to the top edge. The intersecting ribs may be oriented at about 90-60 °, 60-30 °, 60-45 °, 45-30 °, or 30-0 ° relative to the top edge. Typically, the intersecting ribs are located on the face of the membrane that faces the negative electrode. In some embodiments of the invention, the ribbed film can have transverse cross ribs having a height of at least about 0.005mm, 0.01mm, 0.025mm, 0.05mm, 0.075mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1.0 mm. In some embodiments of the invention, the ribbed film can have transverse cross ribs of no greater than about 1.0mm, 0.5mm, 0.25mm, 0.20mm, 0.15mm, 0.10mm, or 0.05mm in height.

In some embodiments of the invention, the ribbed film can have transverse cross ribs having a width of at least about 0.005mm, 0.01mm, 0.025mm, 0.05mm, 0.075mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1.0 mm. In some embodiments of the invention, the ribbed film can have transverse cross ribs of no greater than about 1.0mm, 0.5mm, 0.25mm, 0.20mm, 0.15mm, 0.10mm, or 0.05mm width.

In certain selected embodiments, the porous membrane may have a transverse cross rib height of about 0.10-0.15mm and a longitudinal rib height of about 0.1-0.15 mm. In some embodiments, the porous membrane may have a transverse cross rib height of about 0.10-0.125mm and a longitudinal rib height of about 0.1-0.125 mm.

The microporous membrane may have a backsheet thickness of at least 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1.0 mm. The ribbed separator plate can have a backweb thickness of no greater than about 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, or 0.1 mm. In some embodiments, the microporous membrane may have a backsheet thickness of between about 0.1-1.0mm, 0.1-0.8mm, 0.1-0.5mm, 0.1-0.4mm, 0.1-0.3 mm. In some embodiments, the microporous membrane may have a back web thickness of about 0.2 mm.

The separator of the present invention may be provided in sheet form or in the form of a package, sleeve, pocket or envelope. In some embodiments, the microporous membrane covered on at least one side with at least one fibrous layer is provided as a pocket or envelope. When a fibrous layer is present, it is preferred that the microporous membrane have a larger surface area than the fibrous layer. Thus, when combining a microporous membrane and a fibrous layer, the fibrous layer does not completely cover the microporous layer. Preferably, at least two opposing edge regions of the film layer remain uncovered to provide an edge for heat sealing, which aids in forming a pocket or envelope. The separator may be treated to form a hybrid envelope. The hybrid envelope may be formed by forming one or more slits or openings before, during, or after folding the separator sheet in half and bonding the edges of the separator sheet together to form the envelope. The sides are bonded together using welding or mechanical seals to form a seam that brings one side of the separator sheet into contact with the other side of the separator sheet. For example, heat treatment or ultrasonic treatment may be used to accomplish the welding. This process produces an envelope shape with a bottom folded edge and two lateral edges.

The separator disclosed herein in the form of an envelope may have one or more slits or openings along the fold or seal crease of the envelope. The length of the opening may be at least 1/50^th、1/25^th、1/20^th、1/15^th、1/10^th、1/8^th、1/5^th、1/4^th or 1/3 ^rd of the entire edge length. The length of the opening may be 1/50 ^th to 1/3 ^rd、1/25^th to 1/3 ^rd、1/20^th to 1/3 ^rd、1/20^th to 1/4 ^th、1/15^th to 1/4 ^th、1/15^th to 1/5 ^th or 1/10 ^th to 1/5 ^th of the entire edge length. The hybrid envelope may have 1-5, 1-4, 2-3, or 2 openings, which may or may not be equally disposed along the length of the bottom edge. Preferably there is no opening at the corners of the envelope. The slit may be cut after the separator has been folded and sealed to form the envelope, or may be formed before the porous film is formed into the envelope.

Exemplary separators as disclosed herein may preferably be characterized by having or providing improved electrical conductance over time. The conductance may be determined as a cold start amps (CCA), for example measured in a Midtronics tester. For example, a lead acid battery equipped with a separator of the present invention may exhibit a CCA reduction of less than 10%, less than 9%, less than 8%, less than 7%, less than 6%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, or less than 0.5% over a period of 30 days as measured by a Midtronics tester. In contrast, the CCA reduction observed for conventional batteries under similar conditions is typically much greater.

The separators provided herein allow for reduced water loss and floating current in the cells produced as compared to cells made with conventional separators. In some embodiments, the water loss may be reduced by more than 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 80%. In some embodiments, the floating current may be reduced by more than 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 80%. Batteries prepared using the disclosed separators exhibit an increase in internal resistance that decreases over time, and in some cases, do not.

In addition to reducing moisture loss and extending battery life, a separator that may be preferred may also provide other benefits. For assembly, the separator has a negative cross rib design to maximize bending stiffness and ensure maximum manufacturing productivity. In order to prevent high-speed assembly and short-circuiting in later use, the separator has excellent puncture resistance and oxidation resistance as compared with a standard PE separator.

In accordance with at least selected embodiments, the present disclosure or invention relates to improved battery separators, low ER or high conductivity separators, improved lead acid batteries (e.g., flooded lead acid batteries), high conductivity batteries, and/or improved vehicles including such batteries, and/or methods of making or using such separators or batteries, and/or combinations thereof. In accordance with at least some embodiments, the present disclosure or invention relates to an improved lead acid battery comprising an improved separator and exhibiting increased electrical conductance.

It is believed that the improved separators described herein, such as the split-rib separators described herein, may further help prevent the formation of sulfated crystals, and may also help provide more uniform heat distribution and/or heat mixing and/or heat dissipation (dissipating heat in less time than known separators, such as solid rib separators for flooded lead acid batteries). It is also believed that the example rib-breaking separators described herein may also provide improved or faster or more efficient filling of lead acid batteries, gel batteries, and/or enhanced flooded batteries.

In various embodiments of the present disclosure, the disclosed separators provide reduced acid stratification, or even completely eliminate acid stratification, such that the mixing level or volume uniformity of acid or electrolyte within a flooded lead acid battery is 1.0 or near 1.0. In various embodiments, the separators disclosed herein are also low resistance (ER) separators. In such embodiments, the separator may include improvements, such as improved fillers that 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 high structural morphology and/or reduced particle size and/or a different amount of silanol groups and/or is more hydroxylated than previously known fillers. The improved filler may absorb more oil and/or may allow for the incorporation of greater amounts of process oil during separator formation without simultaneous shrinkage or compression when the oil is removed after extrusion. For example, silica having an intrinsic oil absorption value of about 175-350ml/100g, in some embodiments 200-350ml/100g, in some embodiments 250-350ml/100g, and in other embodiments 260-320ml/100g is used to form the improved separator, although other oil absorption values are possible.

The one or more fillers may include various substances (e.g., polar substances, such as metals) that facilitate the flow of electrolyte and ions through the separator. Such separators are used in rechargeable batteries, such as enhanced flooded batteries, and also result in a decrease in overall resistance.

The low ER microporous separator of the present invention may also include a novel and improved pore morphology and/or a novel and improved fibril morphology such that when such separator is used in a flooded lead acid battery, the separator contributes to a significant reduction in electrical impedance in the flooded lead acid battery. This modified pore morphology and/or fibril morphology may result in a separator whose pores and/or fibrils approximate the roast string (shish-kebab or shish kabob) type morphology. Another way to describe new and improved pore shapes and structures is to texture fibril morphology, wherein silica nodes or nodes of silica are present on a barbecue string type structure on polymer fibrils (fibrils, sometimes referred to as shish) within a battery separator. In addition, in certain embodiments, the silica structure and pore structure of the separator according to the present invention may be described as a skeletal structure or a spinal structure or spinal structure, wherein the silica nodes on the polymer string along the polymer fibrils look like vertebrae or discs ("kebabs") and are sometimes substantially perpendicular to the elongated central spinal column or fibrils (extended chain polymer crystals), which approximate a spinal shape ("shish").

In some cases, an improved battery comprising an improved separator having improved pore morphology and/or fibril morphology may exhibit a 20%, in some cases 25%, in some cases 30%, and in some cases even more than 30% drop in electrical impedance ("ER") that may reduce the internal resistance of the battery, while such a separator maintains and maintains a balance of other critical, desirable mechanical properties of a lead acid battery separator. Furthermore, in certain embodiments, the separators described herein have new and/or improved pore shapes such that more electrolyte flows through or fills the pores and/or voids than known separators. The ultra-high molecular weight polyethylene in the separator may include a polymer of a barbecue string (shish-kebab) configuration including a plurality of extended chain crystals (shish configuration) and a plurality of folded chain crystals (barbecue string configuration), wherein the barbecue string constitutes an average repetition or period of 1nm to 150nm, preferably 10nm to 120nm, and more preferably 20nm to 100nm (at least on a portion of the side of the separator having the ribs). In certain of these low ER embodiments of the present separator, the separator for a lead acid battery described herein comprises a filler selected from the group consisting of silica, precipitated silica, fumed silica, and precipitated amorphous silica; wherein the molecular ratio of OH to Si groups within the filler is in the range of 21:100 to 35:100, in some embodiments in the range of 23:100 to 31:100, in some embodiments 25:100 to 29:100, and in certain preferred embodiments 27:100 or higher, as measured by 29 Si-NMR.

In some cases, an improved battery comprising an improved separator having improved pore morphology and/or fibril morphology may exhibit a 20%, in some cases 25%, in some cases 30%, and in some cases even more than 30% drop in resistance ("ER") that may reduce the internal resistance of the battery, while such a separator maintains and maintains a balance of other critical desirable mechanical properties of a lead acid battery separator. Furthermore, in certain embodiments, the separators described herein have new and/or improved pore shapes such that more electrolyte flows through or fills the pores and/or voids than known separators. The ultra-high molecular weight polyethylene in the separator may include a polymer of a barbecue string (shish-kebab) configuration including a plurality of extended chain crystals (shish configuration) and a plurality of folded chain crystals (barbecue string configuration), wherein the barbecue string constitutes an average repetition or period of 1nm to 150nm, preferably 10nm to 120nm, and more preferably 20nm to 100nm (at least on a portion of the side of the separator having the ribs). In certain of these low ER embodiments of the present separator, the separator for a lead acid battery described herein comprises a filler selected from the group consisting of silica, precipitated silica, fumed silica, and precipitated amorphous silica; wherein the molecular ratio of OH to Si groups within the filler is in the range of 21:100 to 35:100, in some embodiments in the range of 23:100 to 31:100, in some embodiments in the range of 25:100 to 29:100, and in certain preferred embodiments 27:100 or higher, as measured by ²⁹ Si-NMR.

In certain alternative embodiments, the disclosed separator exhibits a reduced electrical resistance, e.g., an electrical resistance of no greater than about 200mΩ.cm²、180mΩ.cm²、160mΩ.cm²、140mΩ.cm²、120mΩ.cm²、100mΩ.cm²、80mΩ.cm²、60mΩ.cm²、50mΩ.cm²、40mΩ.cm²、30mΩ.cm²、 or 20mΩ.cm ². In various embodiments, the separators described herein exhibit an ER reduction of about 20% or more as compared to known separators of the same thickness. For example, a known separator may have an ER value of 60mΩ.cm ²; thus, a separator according to the invention of the same thickness will have an ER value of less than about 48mΩ.cm ². The separators described herein with low ER may have any or all of the features set forth in U.S. provisional patent application No.62/319,959 owned by Daramic, LLC and filed on 8/4 of 2016, which provisional application is incorporated herein by reference in its entirety.

In some embodiments, the improved high conductivity separator may be a low ER separator, a low moisture loss separator, a broken or serrated rib separator, and/or may optionally include a coating on one or both sides. Such coatings may include surfactants or other materials. In some embodiments, the coating may include one or more materials such as described in U.S. patent publication No. 2012/0094183, which is incorporated herein by reference. Such coatings may, for example, reduce the overcharge voltage of the battery system, thereby reducing gate corrosion and preventing drying and/or moisture loss, extending battery life.

The foregoing written description of structures and methods has been presented for purposes of illustration. The embodiments are provided to disclose exemplary embodiments, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. It is not intended to be exhaustive or to limit the invention to the precise steps and/or forms disclosed, and many modifications and variations are possible in light of the above teaching. The features described herein may be combined in any combination. The steps of the methods described herein may be performed in any order that is physically possible. The patentable scope of the invention is defined by the appended claims, and may include other examples that occur to those skilled in the art. Other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

The combination and method of the appended claims are not limited in scope by the specific components and methods described herein, which are intended as illustrations of some aspects of the claims. Any components and methods that are functionally equivalent should fall within the scope of the claims. Various modifications other than the components and methods shown and described herein are intended to fall within the scope of the appended claims. Furthermore, although only certain representative components and method steps disclosed herein are specifically described, other combinations of components and method steps are intended to fall within the scope of the appended claims, even if not specifically recited. Thus, a step, element, component, or combination of components may be explicitly mentioned herein or less, but include other combinations of steps, elements, components, and components and are intended to be included even if not explicitly stated.

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 may be expressed herein as "about" one particular value, and/or "about" 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 will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

"Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

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

Except where indicated, all numbers expressing geometry, dimensions, and so forth, used in the specification and claims are to be understood as being at least partially understood and not intended to limit the application of the doctrine of equivalents to the scope of the claims, construed in light of the number of significant digits and ordinary rounding approaches.

Unless defined otherwise, 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. The publications cited herein and the materials cited therein are specifically incorporated by reference.

Claims

1. A battery separator comprising: a porous backing web having a left portion, a middle portion, and a right portion, wherein,

A first set of broken ribs located in the left portion extending from at least one side of the back web; the first set of broken ribs being divided into a plurality of columns and rows, each of the first set of broken ribs having a first angular orientation relative to the left edge, the first angular orientation being greater than 90 ° and less than 180 °;

A second set of broken ribs extending from the middle of the back web; the second set of broken ribs having a second angular orientation relative to the upper edge, the second angular orientation being greater than 90 ° and less than 180 °; the second group of broken ribs are divided into a plurality of columns and a plurality of rows, and complementary angles are formed between the two columns; and

A third set of broken ribs disposed on the right, the third set of broken ribs disposed in a plurality of rows and a plurality of columns, each of the third set of broken ribs having a third angular orientation relative to the right edge, the third angular orientation being greater than 90 ° and less than 180 °.

2. A battery separator, wherein the battery separator comprises a porous backing web having an upper region, a bottom region, and a central region, the upper region extending downwardly from an upper edge of the backing web; the bottom region extending upwardly from the lower edge of the back web; the central region is located between the upper region and the bottom region;

A plurality of central region ribs extending from the back web from a central region of the back web, the plurality of central region ribs each having an angular orientation relative to the upper edge, the plurality of central region ribs each having an angle complementary to an adjacent one;

A plurality of upper region ribs having an angular orientation relative to the upper edge that is greater than 90 ° and less than 180 °;

the plurality of bottom region ribs have an angular orientation relative to the lower edge that is greater than 90 ° and less than 180 °.

3. A method of reducing acid stratification in a battery comprising: there is provided one or more battery separators as described in claim 1 or 2.

4. A method as in claim 3, further comprising: the battery is placed in the vehicle such that the separator moves parallel to the movement and stops the movement.

5. A method according to claim 3, wherein one or more baffles are provided in an interior space defined at the top of the cell to redirect at least a portion of the electrolyte, which is induced to move to the cell during movement.

6. A lead acid battery comprising the battery separator of claim 1 or 2.

7. A vehicle comprising the lead acid battery of claim 6.

8. A battery separator for enhancing acid mixing in a flooded lead acid battery, comprising:

a porous back web comprising a plurality of broken ribs extending from at least one side of the back web, which are distributed in a pattern in the left, middle, right of the back web, forming mutually alternating raised areas and open areas in the transverse and/or longitudinal direction, the open areas being rib-free spaced areas between two adjacent rows and columns in the transverse and/or longitudinal direction;

at least a portion of the plurality of broken ribs are defined by one or more different angular orientations; the battery separator includes at least one transverse rib on the other side of the backing web or has at least one surfactant on or in the separator.

9. The battery separator of claim 8 wherein said one or more different angular orientations are defined relative to a machine direction of said separator; and the one or more different angular orientations are selected from: greater than 0 ° and less than 180 °, greater than 180 ° and less than 360 °.

10. The battery separator of claim 8 further comprising: one or more sets of ribs within the plurality of broken ribs; and

A first set of the one or more sets of ribs has a first angular orientation; at least a second set of the one or more sets of ribs has a second angular orientation.

11. The battery separator of claim 8 wherein,

The plurality of broken ribs are arranged in an array of columns and rows; the columns are separated by a variable column spacing; and/or the rows are separated by a variable row spacing.

12. The battery separator of claim 8 wherein,

The plurality of broken ribs are arranged in an array; the array of columns is disposed in a plurality of column intervals; and at least one of the plurality of column sections has a different arrangement of a plurality of broken ribs than at least one other of the plurality of column sections, and/or

The plurality of broken ribs are arranged in a row array; the row array is disposed in a plurality of row intervals; and at least one of the plurality of row intervals has a different arrangement of a plurality of broken ribs than at least one other of the plurality of row intervals.

13. The battery separator of claim 8 wherein,

The separator is selected from: polyolefin, rubber, polyvinyl chloride, phenolic resin, cellulose, or combinations thereof;

the separator is selected from: a filler, a surfactant, or a combination thereof; and/or

The battery separator further includes: an absorbent glass mat.

14. The battery separator of claim 8 wherein,

The battery separator further includes a second face rib extending from a side of the back web opposite the plurality of ribs;

the second face-off rib is generally parallel to the transverse direction of the separator; and/or

The second face broken rib is a mini rib; the second face broken rib is a negative side rib; the second face broken rib is a solid rib; the second face broken rib is an intermittent rib; the second surface broken rib is a straight rib; or the second face-broken rib is a sinusoidal rib.

15. A lead acid battery, comprising:

One or more baffles comprising one or more ribs disposed on the baffles, distributed in a pattern on the left, middle, right of the back mesh;

wherein the one or more separators are disposed within the cell at least partially submerged within an acidic electrolyte disposed within the cell;

the one or more ribs promote mixing of the acid electrolyte when the battery is subjected to acceleration; the battery separator includes at least one transverse rib on the other side of the porous backing web, or has at least one surfactant on or in the separator,

A space of two sides of 3mm is reserved between any transverse edge of the separator and the boundary of the side wall of the battery shell; while the headspace above the separator was 44mm for the short cells and 51mm for the high cells.

16. The lead-acid battery of claim 15, wherein the lead-acid battery is a flooded lead-acid battery, a partially charged state-of-operation battery, or for use in an application selected from the group consisting of: idle stop/start applications, power applications, deep cycle applications, or combinations thereof.

17. The lead-acid battery of claim 15, wherein,

The lead-acid battery is subjected to acceleration; each of the one or more baffles is parallel to the direction of the acceleration; and/or

The lead acid battery further includes alternating sequence of positive and negative electrodes, the separator disposed around the negative electrode, the plurality of broken ribs adjacent to the positive electrode; or alternatively

The lead acid battery also includes alternating sequences of positive and negative electrodes, the separator disposed about the positive electrode, the plurality of broken ribs adjacent the negative electrode.

18. A battery separator wherein its porous backing web is divided into at least two portions; at least one part of the ribs is provided with a plurality of inclined broken ribs; wherein one portion has a particularly different rib distribution pattern than another portion; the different rib distribution patterns include: an array of different columns and rows, a rib arrangement of different rows and/or columns, the rib structure comprising a rib shape, a rib orientation, a rib size and/or a rib spacing,

Inversion, reduction, or complete elimination of acid stratification within the cell was quantified using Computational Fluid Dynamics (CFD) and determination of separator enveloping positive or negative plates.

19. The battery separator of claim 18 wherein,

The array of the plurality of columns is divided into a plurality of column intervals; at least one of the plurality of column intervals has a different rib layout than at least one other of the plurality of column intervals;

The array of rows is divided into a plurality of row segments; at least one of the plurality of row segments has a different structural rib layout than at least one other of the plurality of row segments;

the plurality of columns/rows are separated from each other by different column/row spacings;

the other group of broken ribs are arranged on the edge part to form mutually alternate raised areas and open areas, which are distributed between the two rows and are parallel to the edges of the partition board.