Electrode media for use in batteries

Abstract

Articles and methods related to the use of fiber webs comprising glass fibers in electrodes of batteries such as lead acid batteries are generally described. An electrode media provided herein may comprise a fiber web comprising glass fibers of different types. Electrode media provided herein may be configured to be pasted in order to produce an electrode or battery plate. In some embodiments, an article comprising a lug attached to an electrode media is provided. The electrode media described herein may be associated with good electrical, mechanical, and / or thermal performance properties that contribute to their utility in lead acid batteries.

Description

[0001] ELECTRODE MEDIA FOR USE IN BATTERIES

[0002] RELATED APPLICATIONS

[0003] This application claims priority to United Kingdom Patent Application No. 2316551.7, filed October 30, 2023, and entitled “ELECTRODE MEDIA FOR USE IN BATTERIES,” which is incorporated herein by reference in its entirety for all purposes.

[0004] TECHNICAL FIELD

[0005] Electrode media comprising fiber webs for use in batteries, such as lead acid batteries, are generally described.

[0006] BACKGROUND

[0007] In a battery or electrochemical cell, a mechanically durable electrical connection between the active material of an electrode and an external circuit can improve battery performance. For example, classical lead acid batteries or electrochemical cells connect the active material to the circuit by impregnating the active material into a conductive grid, typically made from metallic lead. Improvements in electrical and mechanical properties of connections between active material and external circuits, as well as reductions in electrode weight, are desirable.

[0008] SUMMARY

[0009] Articles and methods related to the use of fiber webs comprising glass fibers in electrodes of batteries such as lead acid batteries are generally described. An electrode media provided herein may comprise a fiber web comprising glass fibers of different types. Electrode media provided herein may be configured to be pasted in order to produce an electrode or battery plate. In some embodiments, an article comprising a lug attached to an electrode media is provided. The electrode media described herein may be associated with good electrical, mechanical, and / or thermal performance properties that contribute to their utility in lead acid batteries.

[0010] The subject matter of the present disclosure involves, in some cases, interrelated products, alternative solutions to a particular problem, and / or a plurality of different uses of one or more systems and / or articles. In one aspect, an electrode media for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, and have an average length of less than or equal to 0.5 mm, an average diameter of greater than or equal to 0.1 microns and less than or equal to 15 microns, and an average aspect ratio of less than or equal to 50; a second plurality of fibers, wherein the second plurality of fibers are staple fibers and have an average diameter of greater than or equal to 1 micron; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron; wherein the first plurality of glass fibers makes up greater than or equal to 2 wt% and less than or equal to 99 wt% or greater than or equal to 15 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; wherein the second plurality of fibers makes up greater than 0 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; and wherein the plurality of multicomponent fibers makes up greater than or equal to 0 wt% and less than or equal to 50 wt% of the total weight of the fibers of the fiber web.

[0011] In another aspect, an electrode media for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, and have an average length of less than or equal to 0.5 mm, an average diameter of greater than or equal to 0.1 microns and less than or equal to 15 microns, and an average aspect ratio of less than or equal to 50; a second plurality of glass fibers, wherein the second plurality of glass fibers are chopped strand fibers and have an average diameter of greater than or equal to 1 micron; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron; wherein the first plurality of glass fibers makes up greater than or equal to 2 wt% and less than or equal to 99 wt% or greater than or equal to 15 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; wherein the second plurality of glass fibers makes up greater than 0 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; and wherein the plurality of multicomponent fibers makes up greater than or equal to 2 wt% and less than or equal to 20 wt% of the total weight of the fibers of the fiber web. In yet another aspect, an electrode media for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web, comprising: a plurality of glass fibers; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron; wherein the plurality of multicomponent fibers makes up greater than or equal to 2 wt% and less than or equal to 20 wt% of the total weight of the fibers of the fiber web, and wherein the multicomponent fibers are present at a first edge of the fiber web and absent from a second edge of the fiber web.

[0012] In another aspect, an electrode media for use in a lead acid battery. According to some embodiments, the electrode media comprises: a fiber web comprising: a first plurality of glass fibers, and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; wherein a plasticity of the fiber web is greater than or equal to 5%, and wherein a basis weight of the fiber web is greater than or equal to 40 gsm.

[0013] In one aspect, an electrode media for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web comprising: a first plurality of glass fibers, and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; wherein a tensile strength of the electrode media is greater than or equal to 2 Ib / inch, wherein an elongation at break of the electrode media is greater than or equal to 1%, and wherein a basis weight of the fiber web is greater than or equal to 40 gsm.

[0014] In an aspect, an electrode media for use in a lead acid battery. According to some embodiments, the electrode media comprises: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, a second plurality of glass fibers, wherein the second plurality of glass fibers are chopped strand fibers or drawn fibers, and a plurality of multicomponent fibers, wherein the fiber web has a maximum pore size of greater than or equal to 20 microns, a density of less than or equal to 250 gsm / mm, and a tensile strength of greater than or equal to 2 Ib / inch.

[0015] In another aspect, an electrode for use in a lead acid battery. According to some embodiments, the electrode comprises: a fiber web comprising: a first plurality of glass fibers; and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers, wherein the fiber web comprises a plurality of pores, wherein an active material is impregnated into the plurality of pores of the fiber web, and wherein the fiber web has a thickness of greater than or equal to 0.25 mm.

[0016] In still another aspect, an electrode for use in a lead acid battery. According to some embodiments, the electrode comprises: a fiber web comprising: a first plurality of glass fibers and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; and an electrically conductive lug interpenetrating with a boundary portion of the fiber web.

[0017] In yet another aspect, an electrode for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web comprising: a plurality of glass fibers; and a plurality of non-glass fibers, wherein an active material is impregnated into the plurality of pores of the fiber web.

[0018] In another aspect, an electrode media for use in a lead acid battery is provided. According to some embodiments, the electrode media comprises: a fiber web comprising: a plurality of glass fibers, and a plurality of staple fibers configured to mechanically reinforce the fiber web, and wherein the fiber web shrinks by less than or equal to 25% when held in air at a temperature of 650 °C for 2 hours.

[0019] In still another aspect, an electrode for use in a lead acid battery is provided. According to some embodiments, the electrode comprises: a fiber web comprising: a plurality of glass fibers and a second plurality of non-glass fibers; and an electrically conductive lug interpenetrating with a boundary portion of the fiber web; wherein an active material is impregnated into said fiber web.

[0020] Other advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments of the disclosure when considered in conjunction with the accompanying figures. In cases where the present specification and a document incorporated by reference include conflicting and / or inconsistent disclosure, the present specification shall control.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS Non-limiting embodiments of the present disclosure will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale unless otherwise indicated. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the disclosure shown where illustration is not necessary to allow those of ordinary skill in the art to understand the disclosure. In the figures:

[0022] FIG. 1 presents a non-limiting schematic top-view illustration of an electrode media, according to some embodiments;

[0023] FIG. 2 presents a non-limiting, schematic illustration of an electrode media connected to a lug, according to some embodiments;

[0024] FIG. 3 presents a non-limiting, schematic illustration of a battery plate comprising an electrode and an electrode media connected to a lug, according to some embodiments;

[0025] FIG. 4 presents a non-limiting schematic illustration of a lug forming machine, according to some embodiments;

[0026] FIG. 5 provides a non-limiting, schematic illustration of impregnation of a paste into an electrode media, according to some embodiments;

[0027] FIG. 6 provides a non-limiting, schematic illustration of a cross-section of a battery, according to some embodiments;

[0028] FIG. 7 provides the tensile strength of a plurality of non-limiting fiber webs as a function of the amount of a plurality of synthetic fibers included in the webs, according to some embodiments;

[0029] FIG. 8 provides the elongation at break of a plurality of non-limiting fiber webs as a function of the amount of a plurality of synthetic fibers included in the webs, according to some embodiments;

[0030] FIG. 9 provides the mean pore size of a plurality of non-limiting fiber webs as a function of the amount of a plurality of synthetic fibers included in the webs, according to some embodiments; FIG. 10 provides the tensile strength of a plurality of non-limiting fiber webs as a function of the amount of a plurality of microglass fibers included in the webs, according to some embodiments;

[0031] FIG. 11 provides the elongation at break of a plurality of non-limiting fiber webs as a function of the amount of a plurality of microglass fibers included in the webs, according to some embodiments; and

[0032] FIG. 12 provides the mean pore size of a plurality of non-limiting fiber webs as a function of the amount of a plurality of microglass fibers included in the webs, according to some embodiments.

[0033] DETAILED DESCRIPTION

[0034] Batteries (e.g., lead acid batteries) are an important commercial technology, whose performance may be improved using the systems and methods provided herein. Lead acid batteries generally include electrodes comprising active materials. The active materials are often prepared as pastes, which may be formed into an electrode by applying the paste to a support structure such as a metal grid. The present disclosure is directed towards an electrode media as support structures that can, in some embodiments, provide weight and performance advantages over the metal grids used in traditional electrode media.

[0035] Electrodes described herein comprise an electrode media, in some embodiments. Generally, an electrode media as described herein comprises a fibrous media that may provide support to, and / or be loaded with, an active material. An electrode media, according to some embodiments, comprises a network suitable to provide structural form to an active material and may be configured to retain an active material within the electrode media (e.g., during a pasting process). For example, an electrode media may comprise a fiber web with interconnected pores formed between the fibers of the web. An electrode media may be configured to retain an active material impregnated into the pores (e.g., interconnected interstices and / or spaces) of the electrode media.

[0036] An electrode media comprises, in at least some embodiments, a fiber web comprising one or more pluralities of fibers. The present disclosure has recognized certain advantages to the use of glass fibers in fiber webs suitable for use in an electrode media. Glass fibers are typically electrically non-conductive, whereas typical electrodes of lead acid batteries include networks (e.g., grids) of electrically conductive materials that help transfer electrons between the active material of the electrode and a circuit during use of the battery. However, it has been discovered in the context of this disclosure that the use of glass fibers in electrode media, despite their electrical nonconductivity, confer a number of advantages to the electrode media that make the fiber webs described herein particularly advantageous for use in electrodes, according to some embodiments. More specifically, and without wishing to be bound by any particular theory, it has been recognized that the use of glass fibers in an electrode media may impart a number of advantageous chemical, mechanical, and thermal advantages to the fiber web that can facilitate highly precise processing of the web without compromising performance of the electrode media in an electrochemical cell. Unexpectedly, electrode media with fiber webs including glass fibers may be particularly advantageous in the context of lead acid battery electrodes, even when the fiber webs are electrically non- conductive.

[0037] In some aspects, the disclosure is directed towards fiber webs well suited for any of a litany of challenging environments and processing conditions that may be associated with preparation and use of an electrode media in an electrochemical cell. For example, a fiber web of an electrode media may be configured to be chemically stable in a lead acid battery, to be pregnable to an active material (e.g., an active material paste) during electrode formation, to have mechanical properties suitable for continuous processing, to have thermal stability suitable for forming an electrically conductive lug onto the electrode media, and / or to have a plasticity suitable for the preparation of a fiber web with a very uniform thickness. In some embodiments, fiber webs with some or all of these properties may be prepared as described below.

[0038] A fiber web of the electrode media may provide the network into which the active material may be impregnated. In some embodiments, a fiber web is non-woven. For example, the fiber web may be a non-woven web prepared using a paper machine or other suitable process. In other embodiments, a fiber web may be woven (e.g., comprising intersecting warp and weft fibers). For example, the fiber web may be knitted.

[0039] A fiber web may comprise one or more pluralities of fibers of different types.

[0040] For example, a fiber web may comprise a first plurality of glass fibers (e.g., a plurality of microglass fibers). In some embodiments, a fiber web comprises a second plurality of fibers. The second plurality of fibers may be fibers different from the fibers of the first plurality of fibers. The differences may lie in the type or method of making the fibers (e.g., glass fibers vs. natural or synthetic fibers, microglass vs. chopped strand glass fibers, staple fibers vs. non-staple fibers), chemical compositions of the fibers, physical characteristics of the fibers (e.g., average diameter, average length, average aspect ratio, size distribution, normally distributed vs. non-normally distributed fibers, etc.), and / or other characteristics of the fibers. In some embodiments, both first and second pluralities of fibers are glass fibers. For example, the glass fibers of the first plurality may be microglass, while the glass fibers of the second plurality are chopped strand glass. In other embodiments, the first plurality of fibers are glass fibers and the second plurality of fibers are non-glass fibers. For example, the second plurality of fibers may be a plurality of synthetic fibers (e.g., a plurality of multicomponent fibers). The second plurality of fibers may be a plurality of natural (e.g., fibrillated) fibers, in some embodiments. In other embodiments, the first plurality of fibers are glass fibers and the second plurality of fibers are staple fibers. In yet other embodiments, the first plurality of fibers are glass fibers and the second plurality of fibers are fibers that have a normally distributed length. In some embodiments an electrode media comprises additional pluralities of fibers (e.g., a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers), including fibers of any of the types described in greater detail below.

[0041] It has been recognized herein that glass fibers with appropriate chemistry and physical properties may be useful for the preparation of electrode media. Glass fibers offer a number of advantages for use in electrodes. For example, glass fibers may have high thermal stability, high chemical stability, and / or favorable mechanical properties. In some embodiments, an electrode media described herein comprises multiple pluralities of glass fibers (e.g., a first plurality of glass fibers and / or a second plurality of glass fibers). For example, the electrode media may comprise glass fibers made from different processes, such as a first plurality of glass fibers comprising microglass fibers and a second plurality of glass fibers comprising chopped strand glass fibers. Fibers of the first plurality may have a composition that is the same as fibers of the second plurality. In some embodiments, the first plurality of the glass fibers and the second plurality of the glass fibers have different chemical compositions. Fibers of the first plurality may differ from fibers of the second plurality by their chemistry (e.g., by their chemical composition) and / or by their physical properties (e.g., by average length, average diameter, size distribution).

[0042] One advantage of the fiber webs provided herein is that, in various embodiments, different types of fibers may have different influences on mechanical properties such as strength, elongation at break, elasticity, and compressibility; physical properties relevant to pasting or lugging processes, such as density, pore size, and heat shrinkage; and processing performance properties such as machinability of a fiber web (e.g., as a qualitative representation of the reliability and ease with which a fiber web may be manufactured or processed using conventional processing techniques such as roll-to-roll handling of the fiber web). This disclosure provides guidance that allows the person of ordinary skill to identify appropriate combinations and relative amounts of various fibers in order to prepare reliable fiber webs for electrode media including its use in an electrochemical cell.

[0043] In some embodiments, the fiber web comprises a first plurality of glass fibers that are microglass fibers. The use of microglass fibers in a fiber web may have a number of advantages. For example, in some embodiments, microglass fibers can be used to control the pore structure of the fiber web. Without wishing to be bound by any particular theory, changing the dimensions (e.g., the average length, the average diameter) or the composition of the microglass fibers and / or changing the proportion of microglass fibers within a fiber web may be used to control pore structure, e.g., by changing the density of entanglements between microglass fibers and other fibers of the fiber web. In some embodiments, the use of microglass fibers is associated with the formation of lower-density fiber webs. Relatedly, in some embodiments, microglass fibers can influence (e.g., increase) the plasticity of a fiber web. In some embodiments, microglass fibers are advantageous for use in fiber webs of electrode media, at least in part because they are hydrophilic and / or have a low contact angle with a lead acid battery electrolyte. Another advantage of microglass fibers recognized herein is that increasing the relative amount of microglass in a fiber web can, in some embodiments, significantly reduce relative pore size, while modestly increasing strength, modestly decreasing elongation at break, and without significantly impacting properties like elasticity, density or compressibility. This may make microglass particularly useful for engineering pore size, thereby controlling performance of the web during pasting. Without wishing to be bound by any particular theory, pore size can be an important consideration in selecting an appropriate fiber web for a pasting process, since pore size may affect the ability of the fiber web to receive the paste.

[0044] A fiber web (e.g., a non-woven fiber web) described herein may comprise glass fibers of the first plurality (e.g., microglass fibers) in any of a variety of suitable amounts. In some embodiments, a first plurality of glass fibers (e.g., a first plurality of microglass fibers) makes up greater than or equal to 2 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, greater than or equal to 45 wt%, greater than or equal to 50 wt%, greater than or equal to 55 wt%, greater than or equal to 60 wt%, greater than or equal to 65 wt%, greater than or equal to 70 wt%, greater than or equal to 75 wt%, greater than or equal to 80 wt%, greater than or equal to 85 wt%, greater than or equal to 90 wt%, or greater than or equal to 95 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a first plurality of glass fibers (e.g., a first plurality of microglass fibers) makes up less than or equal to 99 wt%, less than or equal to 95 wt%, less than or equal to 90 wt%, less than or equal to 85 wt%, less than or equal to 80 wt%, less than or equal to

[0045] 75 wt%, less than or equal to 70 wt%, less than or equal to 65 wt%, less than or equal to

[0046] 60 wt%, less than or equal to 55 wt%, less than or equal to 50 wt%, less than or equal to

[0047] 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to

[0048] 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to

[0049] 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt%, and / or greater than or equal to 2 wt% or greater than or equal to 15 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 2 wt% and less than or equal to 99 wt%, greater than or equal to 15 wt% and less than or equal to 99 wt%, greater than or equal to 30 wt% and less than or equal to 80 wt%, or greater than or equal to 40 wt% and less than or equal to 60 wt% of all fibers in a fiber web (or of the total weight of the fiber web). Other ranges are also possible. A first plurality of glass fibers described herein may have any of a variety of suitable average diameters. For example, the first plurality of glass fibers may comprise microglass fibers. In some embodiments, a first plurality of glass fibers (e.g., a first plurality of microglass fibers) has an average diameter of greater than or equal to 0.1 micron, greater than or equal to 0.2 microns, greater than or equal to 0.5 microns, greater than or equal to 1 micron, greater than or equal to 1.5 microns, greater than or equal to 2 microns, greater than or equal to 2.5 microns, greater than or equal to 3 microns, greater than or equal to 3.5 microns, greater than or equal to 4 microns, greater than or equal to 4.5 microns, greater than or equal to 5 microns, greater than or equal to 5.5 microns, greater than or equal to 6 microns, greater than or equal to 6.5 microns, greater than or equal to 7 microns, greater than or equal to 7.5 microns, greater than or equal to 8 microns, greater than or equal to 8.5 microns, greater than or equal to 9 microns, or greater than or equal to 9.5 microns, and / or less than or equal to 10 microns. In some embodiments, the glass fibers of a first plurality of glass fibers have an average diameter of less than or equal to 10 microns, less than or equal to 9.5 microns, less than or equal to 9 microns, less than or equal to 8.5 microns, less than or equal to 8 microns, less than or equal to 7.5 microns, less than or equal to 7 microns, less than or equal to 6.5 microns, less than or equal to 6 microns, less than or equal to 5.5 microns, less than or equal to 5 microns, less than or equal to 4.5 microns, less than or equal to 4 microns, less than or equal to 3.5 microns, less than or equal to 3 microns, less than or equal to 2.5 microns, less than or equal to 2 microns, less than or equal to 1.5 microns, less than or equal to 1 micron, less than or equal to 0.5 microns, or less than or equal to 0.2 microns, and / or greater than or equal to 0.1 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.1 microns and less than or equal to 10 microns, greater than or equal to 1 micron and less than or equal to 8 microns, greater than or equal to 2 microns and less than or equal to 5 microns, or greater than or equal to 1 micron and less than or equal to 3.5 microns). Other ranges are also possible. The changes brought about by the addition of microglass (e.g., reducing relative pore size, modestly increasing strength, modestly decreasing elongation at break) can, in some cases, be modulated by controlling the average diameter of the microglass fibers. The magnitude of these changes may, in some cases, be increased by decreasing the average diameter of the microglass fibers incorporated into the fiber web. For example, in some embodiments, a fiber web comprising microglass with a 1 micron average diameter may have a smaller pore size than a fiber web comprising an equivalent amount of microglass with a 2 micron diameter.

[0050] The average diameter of the first plurality of fibers may be measured using a Diamscope and measuring at least 10,000 fibers. If the first plurality of fibers has an average length of greater than or equal to 500 microns, the average diameter of the first plurality of fibers may instead be measured using other techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0051] For any measurements disclosed herein using a Diamscope (e.g., average length of a population of fibers, average diameter of the population of fibers, average aspect ratio of the population of fibers), the settings are changed from the factory default settings within the Diamscope’s software as follows: “Histogram bin size” is changed from 0.20 to 0.10; “Maximum width (pm)” is changed from 30.00 to 65.00; “Minimum width (pm)” is set to 0.00; “Minimum fiber length (mm)” is changed from 0.05 to 0.02; “Maximum density of sample” is changed from 5.00 to 3.00; and “Fiber Limit” is changed from 2,000 to 10,000. Further, the Diamscope testing is performed on fiber samples and uses the 0.8mm x 75mm die cutter provided with the Diamscope, a 50ml vial with a screw on cap and 27mm diameter opening, de-ionized water, and a manual pipette with a 4mm opening, 6mm x 80mm stem and an 11mm x 35mm bulb. To prepare the sample, a single layer of fiber is peeled away from the initial sample, with a thickness no greater than 3 mm, and a width and length great enough to lay flat and cover the entire die slot on the cutter. The sample cup supplied with the slicer is placed below the die cutter and the sample is cut with the die cutter. A thin strip of fiber is collected in the sample cup below the die-cutter. This step is repeated until 4 thin strips of fiber are collected in the sample cup. The 4 thin strips of fiber are transferred into a 50 ml vial. The vial is filled with 35 ml of de-ionized water and capped. Then the vial is vigorously shaken vertically for 1 minute to disperse the fibers. The cap is removed from the vial, and a liquid sample is slowly drawn from the vial using the pipette described above, starting the draw 5 mm from the bottom and ending 5 mm from the surface of the sample. The sample is ejected into the Diamscope’s sample bowl. Within the Diamscope software, the “start scan” button is clicked, such that the sample is pre-mixed in the sample bowl for 30 seconds, after which time the fiber analysis will automatically begin. Once the fiber analysis has completed, the Diamscope will automatically report out the pertinent data. Within the data report, the mean average glass fiber diameter (pm) for the sample analyzed is listed and the mean average glass fiber length (mm) is listed. For any measurements disclosed herein, unless otherwise specified, it should be understood that the “average” value of the measurement (e.g., the average length, the average diameter of a plurality of fibers) refers to the arithmetic average.

[0052] Generally, a plurality of fibers (e.g., a first plurality of glass fibers, a second plurality of glass fibers) has a size distribution. In some embodiments, a size distribution of a plurality glass fibers is approximately normally distributed (e.g., the plurality of glass fibers has a normally distributed length and / or a normally distributed diameter). For example, chopped strand glass fibers may have a normally distributed size or length distribution. However, in some embodiments, a plurality of glass fiber has a non- normally distributed size distribution.

[0053] A first plurality of glass fibers described herein may have any of a variety of suitable average lengths. In some embodiments, a first plurality of glass fibers (e.g., a first plurality of microglass fibers) has an average length of greater than or equal to 50 microns, greater than or equal to 100 microns, greater than or equal to 150 microns, greater than or equal to 200 microns, greater than or equal to 250 microns, greater than or equal to 300 microns, greater than or equal to 350 microns, greater than or equal to 400 microns, greater than or equal to 450 microns, greater than or equal to 500 microns, greater than or equal to 550 microns, greater than or equal to 600 microns, greater than or equal to 650 microns, greater than or equal to 700 microns, greater than or equal to 750 microns, greater than or equal to 800 microns, greater than or equal to 850 microns, greater than or equal to 900 microns, or greater than or equal to 950 microns, and / or less than or equal to 1000 microns. In some embodiments, a first plurality of glass fibers (e.g., a first plurality of microglass fibers) has an average length of less than or equal to 1000 microns, less than or equal to 950 microns, less than or equal to 900 microns, less than or equal to 850 microns, less than or equal to 800 microns, less than or equal to 750 microns, less than or equal to 700 microns, less than or equal to 650 microns, less than or equal to 600 microns, less than or equal to 550 microns, less than or equal to 500 microns, less than or equal to 450 microns, less than or equal to 400 microns, less than or equal to 350 microns, less than or equal to 300 microns, less than or equal to 250 microns, less than or equal to 200 microns, less than or equal to 150 microns, or less than or equal to 100 microns, and / or greater than or equal to 50 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 50 microns and less than or equal to 1000 microns, greater than or equal to 50 microns and less than or equal to 400 microns, or greater than or equal to 100 microns and less than or equal to 200 microns). Other ranges are also possible. If the first plurality of fibers has an average length of greater than or equal to 500 microns, the average length of the first plurality of fibers may instead be measured using other techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0054] The average length of the first plurality of fibers may be measured using a Diamscope and measuring at least 10,000 fibers.

[0055] A first plurality of glass fibers described herein may have any of a variety of suitable average aspect ratios between the fibers’ length and diameter. In some embodiments, a first plurality of glass fibers has an average aspect ratio of greater than or equal to 1, greater than or equal to 10, greater than or equal to 30, greater than or equal to 50, greater than or equal to 80, greater than or equal to 100, greater than or equal to 130, greater than or equal to 150, greater than or equal to 180, greater than or equal to 200, greater than or equal to 230, greater than or equal to 250, or greater than or equal to 280, and / or less than or equal to 300. In some embodiments, a first plurality of glass fibers has an average aspect ratio of less than or equal to 300, less than or equal to 280, less than or equal to 250, less than or equal to 230, less than or equal to 200, less than or equal to 180, less than or equal to 150, less than or equal to 130, less than or equal to 100, less than or equal to 80, less than or equal to 50, less than or equal to 30, or less than or equal to 10, and / or greater than or equal to 1. Combinations of these ranges are also possible (e.g., greater than or equal to 1 and less than or equal to 300, greater than or equal to 10 and less than or equal to 150, or greater than or equal to 30 and less than or equal to 100). Other ranges are also possible.

[0056] The average aspect ratio of the first plurality of fibers may be measured using a Diamscope and measuring at least 10,000 fibers. If the first plurality of fibers has an average length of greater than or equal to 500 microns, the average aspect ratio of the first plurality of fibers may instead be measured using other techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM). A fiber web (e.g., a non-woven fiber web) described herein may comprise a second plurality of glass fibers. For example, a fiber web may comprise a second plurality of fibers that are chopped strand glass fibers. A second plurality of fibers may be included in any of a variety of suitable amounts.

[0057] In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) makes up greater than or equal to greater than or equal to 0 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, greater than or equal to 45 wt%, greater than or equal to 50 wt%, greater than or equal to 55 wt%, greater than or equal to 60 wt%, greater than or equal to 65 wt%, greater than or equal to 70 wt%, greater than or equal to 75 wt%, greater than or equal to 80 wt%, or greater than or equal to 85 wt%, and / or less than or equal to 90 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) makes up less than or equal to 90 wt%, less than or equal to 85 wt%, less than or equal to 80 wt%, less than or equal to 75 wt%, less than or equal to 70 wt%, less than or equal to 65 wt%, less than or equal to 60 wt%, less than or equal to 55 wt%, less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 90 wt%, greater than or equal to 10 wt% and less than or equal to 50 wt%, or greater than or equal to 20 wt% and less than or equal to 40 wt%). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of glass fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of glass fibers, depending on the embodiment, as the disclosure is not so limited.

[0058] A second plurality of glass fibers described herein may have any of a variety of suitable average diameters. In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) has an average diameter of greater than or equal to 5 microns, greater than or equal to 6 microns, greater than or equal to 7 microns, greater than or equal to 8 microns, greater than or equal to 9 microns, greater than or equal to 10 microns, greater than or equal to 11 microns, greater than or equal to 12 microns, greater than or equal to 13 microns, greater than or equal to 14 microns, greater than or equal to 15 microns, greater than or equal to 16 microns, greater than or equal to 17 microns, greater than or equal to 18 microns, greater than or equal to 19 microns, greater than or equal to 20 microns, greater than or equal to 21 microns, greater than or equal to 22 microns, greater than or equal to 23 microns, or greater than or equal to 24 microns, and / or less than or equal to 25 microns. In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) has an average diameter of less than or equal to 25 microns, less than or equal to 24 microns, less than or equal to 23 microns, less than or equal to 22 microns, less than or equal to 21 microns, less than or equal to 20 microns, less than or equal to 19 microns, less than or equal to 18 microns, less than or equal to 17 microns, less than or equal to 16 microns, less than or equal to 15 microns, less than or equal to 14 microns, less than or equal to 13 microns, less than or equal to 12 microns, less than or equal to 11 microns, less than or equal to 10 microns, less than or equal to 9 microns, less than or equal to 8 microns, less than or equal to 7 microns, or less than or equal to 6 microns, and / or greater than or equal to 5 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 5 microns and less than or equal to 25 microns, greater than or equal to 10 microns and less than or equal to 20 microns, or greater than or equal to 12 microns and less than or equal to 16 microns). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of glass fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of glass fibers, depending on the embodiment, as the disclosure is not so limited.

[0059] The average diameter of the second plurality of fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0060] A second plurality of glass fibers described herein may have any of a variety of suitable average lengths. In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) has an average length of greater than or equal to 2 mm, greater than or equal to 5 mm, greater than or equal to 7 mm, greater than or equal to 10 mm, greater than or equal to 12 mm, greater than or equal to 15 mm, greater than or equal to 17 mm, greater than or equal to 20 mm, greater than or equal to 22 mm, greater than or equal to 25 mm, greater than or equal to 27 mm, greater than or equal to 30 mm, greater than or equal to 32 mm, greater than or equal to 35 mm, greater than or equal to 37 mm, greater than or equal to 40 mm, greater than or equal to 42 mm, greater than or equal to 45 mm, or greater than or equal to 47 mm, and / or less than or equal to 50 mm. In some embodiments, a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) has an average length of less than or equal to 50 mm, less than or equal to 47 mm, less than or equal to 45 mm, less than or equal to 42 mm, less than or equal to 40 mm, less than or equal to 37 mm, less than or equal to 35 mm, less than or equal to 32 mm, less than or equal to 30 mm, less than or equal to 27 mm, less than or equal to 25 mm, less than or equal to 22 mm, less than or equal to 20 mm, less than or equal to 17 mm, less than or equal to 15 mm, less than or equal to 12 mm, less than or equal to 10 mm, less than or equal to 7 mm, or less than or equal to 5 mm, and / or greater than or equal to 1 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 2 mm and less than or equal to 50 mm, greater than or equal to 5 mm and less than or equal to 20 mm, or greater than or equal to 10 mm and less than or equal to 15 mm). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of glass fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of glass fibers, depending on the embodiment, as the disclosure is not so limited.

[0061] The average length of the second plurality of fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0062] The glass fibers described herein may have any of a variety of appropriate chemical compositions. Typically, a glass fiber includes a chemical composition comprising a variety of different chemical compounds that together give the glass fiber certain desirable physical characteristics. For example, a glass fiber for use in an electrode media described herein may have a chemical composition that includes several of the chemical compounds described below in an amount specified in one or more ranges described below. Other additives may optionally be present in the chemical composition.

[0063] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise SiO2 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises S i O2 in an amount of greater than or equal to 50 wt%, greater than or equal to 52 wt%, greater than or equal to 55 wt%, greater than or equal to 58 wt%, greater than or equal to 60 wt%, greater than or equal to 62 wt%, greater than or equal to 65 wt%, greater than or equal to 68 wt%, greater than or equal to 70 wt%, greater than or equal to 72 wt%, greater than or equal to 75 wt%, greater than or equal to 78 wt%, greater than or equal to 80 wt%, greater than or equal to 82 wt%, greater than or equal to 85 wt%, or greater than or equal to 88 wt%. In some embodiments, a glass fiber comprises SiCh in an amount of less than or equal to 90 wt%, less than or equal to 88 wt%, less than or equal to 85 wt%, less than or equal to 82 wt%, less than or equal to 80 wt%, less than or equal to 78 wt%, less than or equal to 75 wt%, less than or equal to 72 wt%, less than or equal to 70 wt%, less than or equal to 68 wt%, less than or equal to 65 wt%, less than or equal to 62 wt%, less than or equal to 60 wt%, less than or equal to 58 wt%, less than or equal to 55 wt%, or less than or equal to 52 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 50 wt% and less than or equal to 90 wt%, greater than or equal to 55 wt% and less than or equal to 80 wt%, or greater than or equal to 60 wt% and less than or equal to 75 wt%). Other ranges are also possible.

[0064] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise AI2O3 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises AI2O3 in an amount of greater than or equal to 1 wt%, greater than or equal to 2 wt%, greater than or equal to 3 wt%, greater than or equal to 4 wt%, greater than or equal to 5 wt%, greater than or equal to 6 wt%, greater than or equal to 7 wt%, greater than or equal to 8 wt%, greater than or equal to 9 wt%, greater than or equal to 10 wt%, greater than or equal to 11 wt%, greater than or equal to 12 wt%, greater than or equal to 13 wt%, greater than or equal to 14 wt%, greater than or equal to 15 wt%, greater than or equal to 16 wt%, greater than or equal to 17 wt%, greater than or equal to 18 wt%, or greater than or equal to 19 wt%. In some embodiments, a glass fiber comprises AI2O3 in an amount of less than or equal to 20 wt%, less than or equal to 19 wt%, less than or equal to 18 wt%, less than or equal to 17 wt%, less than or equal to 16 wt%, less than or equal to 15 wt%, less than or equal to 14 wt%, less than or equal to 13 wt%, less than or equal to 12 wt%, less than or equal to 11 wt%, less than or equal to 10 wt%, less than or equal to 9 wt%, less than or equal to 8 wt%, less than or equal to 7 wt%, less than or equal to 6 wt%, less than or equal to 5 wt%, less than or equal to 4 wt%, less than or equal to 3 wt%, or less than or equal to 2 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 1 wt% and less than or equal to 20 wt%, greater than or equal to 2 wt% and less than or equal to 11 wt%, or greater than or equal to 3 wt% and less than or equal to 5 wt%). Other ranges are also possible.

[0065] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise CaO in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises CaO in an amount of greater than or equal to 2 wt%, greater than or equal to 3 wt%, greater than or equal to 4 wt%, greater than or equal to 5 wt%, greater than or equal to 6 wt%, greater than or equal to 7 wt%, greater than or equal to 8 wt%, greater than or equal to 9 wt%, greater than or equal to 10 wt%, greater than or equal to 11 wt%, greater than or equal to 12 wt%, greater than or equal to 13 wt%, greater than or equal to 14 wt%, greater than or equal to 15 wt%, greater than or equal to 16 wt%, greater than or equal to 17 wt%, greater than or equal to 18 wt%, greater than or equal to 19 wt%, greater than or equal to 20 wt%, greater than or equal to 21 wt%, greater than or equal to 22 wt%, greater than or equal to 23 wt%, or greater than or equal to 24 wt%. In some embodiments, a glass fiber comprises CaO in an amount of less than or equal to 25 wt%, less than or equal to 24 wt%, less than or equal to 23 wt%, less than or equal to 22 wt%, less than or equal to 21 wt%, less than or equal to 20 wt%, less than or equal to 19 wt%, less than or equal to 18 wt%, less than or equal to 17 wt%, less than or equal to 16 wt%, less than or equal to 15 wt%, less than or equal to 14 wt%, less than or equal to 13 wt%, less than or equal to 12 wt%, less than or equal to 11 wt%, less than or equal to 10 wt%, less than or equal to 9 wt%, less than or equal to 8 wt%, less than or equal to 7 wt%, less than or equal to 6 wt%, less than or equal to 5 wt%, less than or equal to 4 wt%, or less than or equal to 3 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 2 wt% and less than or equal to 25 wt%, greater than or equal to 3 wt% and less than or equal to 14 wt%, or greater than or equal to 4 wt% and less than or equal to 7 wt%). Other ranges are also possible.

[0066] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise MgO in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises MgO in an amount of greater than or equal to 0 wt%, greater than or equal to 0.5 wt%, greater than or equal to 1 wt%, greater than or equal to 1.5 wt%, greater than or equal to 2 wt%, greater than or equal to 2.5 wt%, greater than or equal to 3 wt%, greater than or equal to 3.5 wt%, greater than or equal to 4 wt%, greater than or equal to 4.5 wt%, greater than or equal to 5 wt%, or greater than or equal to 5.5 wt%. In some embodiments, a glass fiber comprises MgO in an amount of less than or equal to 6 wt%, less than or equal to 5.5 wt%, less than or equal to 5 wt%, less than or equal to 4.5 wt%, less than or equal to 4 wt%, less than or equal to 3.5 wt%, less than or equal to 3 wt%, less than or equal to 2.5 wt%, less than or equal to 2 wt%, less than or equal to 1.5 wt%, less than or equal to 1 wt%, or less than or equal to 0.5 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 6 wt%, greater than or equal to 1.5 wt% and less than or equal to 5 wt%, or greater than or equal to 2 wt% and less than or equal to 4 wt%). Other ranges are also possible.

[0067] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Na2O in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Na2O in an amount of greater than or equal to 6 wt%, greater than or equal to 7 wt%, greater than or equal to 8 wt%, greater than or equal to 9 wt%, greater than or equal to 10 wt%, greater than or equal to 11 wt%, greater than or equal to 12 wt%, greater than or equal to 13 wt%, greater than or equal to 14 wt%, greater than or equal to 15 wt%, greater than or equal to 16 wt%, greater than or equal to 17 wt%, greater than or equal to 18 wt%, greater than or equal to 19 wt%, or greater than or equal to 20 wt%. In some embodiments, a glass fiber comprises Na2<D in an amount of less than or equal to 21 wt%, less than or equal to 20 wt%, less than or equal to 19 wt%, less than or equal to 18 wt%, less than or equal to 17 wt%, less than or equal to 16 wt%, less than or equal to 15 wt%, less than or equal to 14 wt%, less than or equal to 13 wt%, less than or equal to 12 wt%, less than or equal to 11 wt%, less than or equal to 10 wt%, less than or equal to 9 wt%, less than or equal to 8 wt%, or less than or equal to 7 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 6 wt% and less than or equal to 21 wt%, greater than or equal to 8 wt% and less than or equal to 19 wt%, or greater than or equal to 10 wt% and less than or equal to 17 wt%). Other ranges are also possible. A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise K2O in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises K2O in an amount of greater than or equal to 0 wt%, greater than or equal to 0.5 wt%, greater than or equal to 1 wt%, greater than or equal to 1.5 wt%, greater than or equal to 2 wt%, greater than or equal to 2.5 wt%, greater than or equal to 3 wt%, greater than or equal to 3.5 wt%, greater than or equal to 4 wt%, or greater than or equal to 4.5 wt%. In some embodiments, a glass fiber comprises K2O in an amount of less than or equal to 5 wt%, less than or equal to 4.5 wt%, less than or equal to 4 wt%, less than or equal to 3.5 wt%, less than or equal to 3 wt%, less than or equal to 2.5 wt%, less than or equal to 2 wt%, less than or equal to 1.5 wt%, less than or equal to 1 wt%, or less than or equal to 0.5 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 5 wt%, greater than or equal to 0.5 wt% and less than or equal to 4 wt%, or greater than or equal to 1 wt% and less than or equal to 3 wt%). Other ranges are also possible.

[0068] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise B2O3 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises B2O3 in an amount of greater than or equal to 0 wt%, greater than or equal to 0.5 wt%, greater than or equal to 1 wt%, greater than or equal to 1.5 wt%, greater than or equal to 2 wt%, greater than or equal to 2.5 wt%, greater than or equal to 3 wt%, greater than or equal to 3.5 wt%, greater than or equal to 4 wt%, greater than or equal to 4.5 wt%, greater than or equal to 5 wt%, greater than or equal to 5.5 wt%, greater than or equal to 6 wt%, greater than or equal to 6.5 wt%, greater than or equal to 7 wt%, greater than or equal to 7.5 wt%, greater than or equal to 8 wt%, or greater than or equal to 8.5 wt%. In some embodiments, a glass fiber comprises B2O3 in an amount of less than or equal to 9 wt%, less than or equal to 8.5 wt%, less than or equal to 8 wt%, less than or equal to 7.5 wt%, less than or equal to 7 wt%, less than or equal to 6.5 wt%, less than or equal to 6 wt%, less than or equal to 5.5 wt%, less than or equal to 5 wt%, less than or equal to 4.5 wt%, less than or equal to 4 wt%, less than or equal to 3.5 wt%, less than or equal to 3 wt%, less than or equal to 2.5 wt%, less than or equal to 2 wt%, less than or equal to 1.5 wt%, less than or equal to 1 wt%, or less than or equal to 0.5 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 9 wt%, greater than or equal to 3 wt% and less than or equal to 8 wt%, or greater than or equal to 4 wt% and less than or equal to 7 wt%). Other ranges are also possible.

[0069] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Fe2O3 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Fe2O3 in an amount of less than or equal to 1.00 wt%, less than or equal to 0.95 wt%, less than or equal to 0.90 wt%, less than or equal to 0.85 wt%, less than or equal to 0.80 wt%, less than or equal to 0.75 wt%, less than or equal to 0.70 wt%, less than or equal to 0.65 wt%, less than or equal to 0.60 wt%, less than or equal to 0.55 wt%, less than or equal to 0.50 wt%, less than or equal to 0.45 wt%, less than or equal to 0.40 wt%, less than or equal to 0.35 wt%, less than or equal to 0.30 wt%, less than or equal to 0.25 wt%, less than or equal to 0.20 wt%, less than or equal to 0.15 wt%, less than or equal to 0.10 wt%, or less than or equal to 0.05 wt%. In some embodiments, a glass fiber comprises Fe2<D3 in an amount of greater than or equal to 0.00 wt%, greater than or equal to 0.05 wt%, greater than or equal to 0.10 wt%, greater than or equal to 0.15 wt%, greater than or equal to 0.20 wt%, greater than or equal to 0.25 wt%, greater than or equal to 0.30 wt%, greater than or equal to 0.35 wt%, greater than or equal to 0.40 wt%, greater than or equal to 0.45 wt%, greater than or equal to 0.50 wt%, greater than or equal to 0.55 wt%, greater than or equal to 0.60 wt%, greater than or equal to 0.65 wt%, greater than or equal to 0.70 wt%, greater than or equal to 0.75 wt%, greater than or equal to 0.80 wt%, greater than or equal to 0.85 wt%, greater than or equal to 0.90 wt%, or greater than or equal to 0.95 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0.00 wt% and less than or equal to 1.00 wt%, greater than or equal to 0.00 wt% and less than or equal to 0.75 wt%, or greater than or equal to 0.00 wt% and less than or equal to 0.05 wt%). Other ranges are also possible.

[0070] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise TiO2 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises TiO2 in an amount of less than or equal to 1.50 wt%, less than or equal to 1.45 wt%, less than or equal to 1.40 wt%, less than or equal to 1.35 wt%, less than or equal to 1.30 wt%, less than or equal to 1.25 wt%, less than or equal to 1.20 wt%, less than or equal to 1.15 wt%, less than or equal to 1.10 wt%, less than or equal to 1.05 wt%, less than or equal to 1.00 wt%, less than or equal to 0.95 wt%, less than or equal to 0.90 wt%, less than or equal to 0.85 wt%, less than or equal to 0.80 wt%, less than or equal to 0.75 wt%, less than or equal to 0.70 wt%, less than or equal to 0.65 wt%, less than or equal to 0.60 wt%, less than or equal to 0.55 wt%, less than or equal to 0.50 wt%, less than or equal to 0.45 wt%, less than or equal to 0.40 wt%, less than or equal to 0.35 wt%, less than or equal to 0.30 wt%, less than or equal to 0.25 wt%, less than or equal to 0.20 wt%, less than or equal to 0.15 wt%, less than or equal to 0.10 wt%, or less than or equal to 0.05 wt%. In some embodiments, a glass fiber comprises TiCh in an amount of greater than or equal to 0.00 wt%, greater than or equal to 0.05 wt%, greater than or equal to 0.10 wt%, greater than or equal to 0.15 wt%, greater than or equal to 0.20 wt%, greater than or equal to 0.25 wt%, greater than or equal to 0.30 wt%, greater than or equal to 0.35 wt%, greater than or equal to 0.40 wt%, greater than or equal to 0.45 wt%, greater than or equal to 0.50 wt%, greater than or equal to 0.55 wt%, greater than or equal to 0.60 wt%, greater than or equal to 0.65 wt%, greater than or equal to 0.70 wt%, greater than or equal to 0.75 wt%, greater than or equal to 0.80 wt%, greater than or equal to 0.85 wt%, greater than or equal to 0.90 wt%, greater than or equal to 0.95 wt%, greater than or equal to 1.00 wt%, greater than or equal to 1.05 wt%, greater than or equal to 1.10 wt%, greater than or equal to 1.15 wt%, greater than or equal to 1.20 wt%, greater than or equal to 1.25 wt%, greater than or equal to 1.30 wt%, greater than or equal to 1.35 wt%, greater than or equal to 1.40 wt%, or greater than or equal to 1.45 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0.00 wt% and less than or equal to 1.50 wt%, greater than or equal to 0.00 wt% and less than or equal to 0.10 wt%, or greater than or equal to 0.00 wt% and less than or equal to 0.05 wt%). Other ranges are also possible.

[0071] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise BaO in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises BaO in an amount of less than or equal to 0.300 wt%, less than or equal to 0.275 wt%, less than or equal to 0.250 wt%, less than or equal to 0.225 wt%, less than or equal to 0.200 wt%, less than or equal to 0.175 wt%, less than or equal to 0.150 wt%, less than or equal to 0.125 wt%, less than or equal to 0.100 wt%, less than or equal to 0.075 wt%, less than or equal to 0.050 wt%, or less than or equal to 0.025 wt%. In some embodiments, a glass fiber comprises BaO in an amount of greater than or equal to 0.000 wt%, greater than or equal to 0.025 wt%, greater than or equal to 0.050 wt%, greater than or equal to 0.075 wt%, greater than or equal to 0.100 wt%, greater than or equal to 0.125 wt%, greater than or equal to 0.150 wt%, greater than or equal to 0.175 wt%, greater than or equal to 0.200 wt%, greater than or equal to 0.225 wt%, greater than or equal to 0.250 wt%, or greater than or equal to 0.275 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0.000 wt% and less than or equal to 0.300 wt%, greater than or equal to 0.000 wt% and less than or equal to 0.200 wt%, or greater than or equal to 0.000 wt% and less than or equal to 0.100 wt%). Other ranges are also possible.

[0072] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise ZnO in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises ZnO in an amount of less than or equal to 0.500 wt%, less than or equal to 0.475 wt%, less than or equal to 0.450 wt%, less than or equal to 0.425 wt%, less than or equal to 0.400 wt%, less than or equal to 0.375 wt%, less than or equal to 0.350 wt%, less than or equal to 0.325 wt%, less than or equal to 0.300 wt%, less than or equal to 0.275 wt%, less than or equal to 0.250 wt%, less than or equal to 0.225 wt%, less than or equal to 0.200 wt%, less than or equal to 0.175 wt%, less than or equal to 0.150 wt%, less than or equal to 0.125 wt%, less than or equal to 0.100 wt%, less than or equal to 0.075 wt%, less than or equal to 0.050 wt%, or less than or equal to 0.025 wt%. In some embodiments, a glass fiber comprises ZnO in an amount of greater than or equal to 0.000 wt%, greater than or equal to 0.025 wt%, greater than or equal to 0.050 wt%, greater than or equal to 0.075 wt%, greater than or equal to 0.100 wt%, greater than or equal to 0.125 wt%, greater than or equal to 0.150 wt%, greater than or equal to 0.175 wt%, greater than or equal to 0.200 wt%, greater than or equal to 0.225 wt%, greater than or equal to 0.250 wt%, greater than or equal to 0.275 wt%, greater than or equal to 0.300 wt%, greater than or equal to 0.325 wt%, greater than or equal to 0.350 wt%, greater than or equal to 0.375 wt%, greater than or equal to 0.400 wt%, greater than or equal to 0.425 wt%, greater than or equal to 0.450 wt%, or greater than or equal to 0.475 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0.000 wt% and less than or equal to 0.500 wt%, greater than or equal to 0.000 wt% and less than or equal to 0.200 wt%, or greater than or equal to 0.000 wt% and less than or equal to 0.100 wt%). Other ranges are also possible. A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise F2 in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises F2 in an amount of less than or equal to 0.300 wt%, less than or equal to 0.275 wt%, less than or equal to 0.250 wt%, less than or equal to 0.225 wt%, less than or equal to 0.200 wt%, less than or equal to 0.175 wt%, less than or equal to 0.150 wt%, less than or equal to 0.125 wt%, less than or equal to 0.100 wt%, less than or equal to 0.075 wt%, less than or equal to 0.050 wt%, or less than or equal to 0.025 wt%. In some embodiments, a glass fiber comprises F2 in an amount of greater than or equal to 0.000 wt%, greater than or equal to 0.025 wt%, greater than or equal to 0.050 wt%, greater than or equal to 0.075 wt%, greater than or equal to 0.100 wt%, greater than or equal to 0.125 wt%, greater than or equal to 0.150 wt%, greater than or equal to 0.175 wt%, greater than or equal to 0.200 wt%, greater than or equal to 0.225 wt%, greater than or equal to 0.250 wt%, or greater than or equal to 0.275 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0.000 wt% and less than or equal to 0.300 wt%, greater than or equal to 0.000 wt% and less than or equal to 0.200 wt%, or greater than or equal to 0.000 wt% and less than or equal to 0.100 wt%). Other ranges are also possible.

[0073] It should, of course, be understood that a plurality of glass fibers described herein (e.g., a first plurality of glass fibers, a second plurality of glass fibers) may have a chemical composition comprising a mixture of chemical compounds, each chemical compound being present in an amount specified within the above-mentioned ranges. In embodiments wherein an electrode media comprises multiple pluralities of glass fibers, it should be understood that, in some embodiments, each plurality of glass fibers may independently have a chemical composition comprising a mixture of chemical compounds, each chemical compound being present in an amount specified within the above-mentioned ranges. The second composition may be the same as the first composition, or may differ from the first composition, depending on the embodiment. Any of a variety of suitable glass compositions may be used. Examples of suitable glass compositions that may be used include but are not limited to M glass, C glass, 253 glass, or glasses compositionally similar to Advantex ® glass produced by Owens Coming.

[0074] It may be advantageous for the glass fibers of an electrode media described herein to be relatively free of certain impurities. For example, without wishing to be bound by any particular theory, glass fibers relatively free of certain impurities may have higher thermal stability or chemical stability. The thermal stability and / or chemical stability resulting from the relative freedom of glass fibers from certain impurities may be advantageous for processing and / or use of an electrode media comprising the glass fibers.

[0075] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Li in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Li in an amount of less than or equal to 5 wt ppm (parts per million, by weight), less than or equal to 4.8 wt ppm, less than or equal to 4.6 wt ppm, less than or equal to 4.4 wt ppm, less than or equal to 4.2 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.8 wt ppm, less than or equal to 3.6 wt ppm, less than or equal to 3.4 wt ppm, less than or equal to 3.2 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.8 wt ppm, less than or equal to 2.6 wt ppm, less than or equal to 2.4 wt ppm, less than or equal to 2.2 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.8 wt ppm, less than or equal to 1.6 wt ppm, less than or equal to 1.4 wt ppm, less than or equal to 1.2 wt ppm, less than or equal to 1 wt ppm, less than or equal to 0.8 wt ppm, less than or equal to 0.6 wt ppm, less than or equal to 0.4 wt ppm, or less than or equal to 0.2 wt ppm. In some embodiments, a glass fiber comprises Li in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.2 wt ppm, greater than or equal to 0.4 wt ppm, greater than or equal to 0.6 wt ppm, greater than or equal to 0.8 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.2 wt ppm, greater than or equal to 1.4 wt ppm, greater than or equal to 1.6 wt ppm, greater than or equal to 1.8 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.2 wt ppm, greater than or equal to 2.4 wt ppm, greater than or equal to 2.6 wt ppm, greater than or equal to 2.8 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.2 wt ppm, greater than or equal to 3.4 wt ppm, greater than or equal to 3.6 wt ppm, greater than or equal to 3.8 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.2 wt ppm, greater than or equal to 4.4 wt ppm, greater than or equal to 4.6 wt ppm, or greater than or equal to 4.8 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 5 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 1.2 wt ppm, or greater than or - 1 - equal to 0 wt ppm and less than or equal to 0.8 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Li.

[0076] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Pb in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Pb in an amount of less than or equal to 15 wt ppm, less than or equal to 14.5 wt ppm, less than or equal to 14 wt ppm, less than or equal to 13.5 wt ppm, less than or equal to 13 wt ppm, less than or equal to 12.5 wt ppm, less than or equal to 12 wt ppm, less than or equal to 11.5 wt ppm, less than or equal to 11 wt ppm, less than or equal to 10.5 wt ppm, less than or equal to 10 wt ppm, less than or equal to 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Pb in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, greater than or equal to 9.5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 10.5 wt ppm, greater than or equal to 11 wt ppm, greater than or equal to 11.5 wt ppm, greater than or equal to 12 wt ppm, greater than or equal to 12.5 wt ppm, greater than or equal to 13 wt ppm, greater than or equal to 13.5 wt ppm, greater than or equal to 14 wt ppm, or greater than or equal to 14.5 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 15 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 7.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 4.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Pb.

[0077] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Sr in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Sr in an amount of less than or equal to 90 wt ppm, less than or equal to 85 wt ppm, less than or equal to 80 wt ppm, less than or equal to 75 wt ppm, less than or equal to 70 wt ppm, less than or equal to 65 wt ppm, less than or equal to 60 wt ppm, less than or equal to 55 wt ppm, less than or equal to 50 wt ppm, less than or equal to 45 wt ppm, less than or equal to 40 wt ppm, less than or equal to 35 wt ppm, less than or equal to 30 wt ppm, less than or equal to 25 wt ppm, less than or equal to 20 wt ppm, less than or equal to 15 wt ppm, less than or equal to 10 wt ppm, or less than or equal to 5 wt ppm. In some embodiments, a glass fiber comprises Sr in an amount of greater than or equal to 0 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 15 wt ppm, greater than or equal to 20 wt ppm, greater than or equal to 25 wt ppm, greater than or equal to 30 wt ppm, greater than or equal to 35 wt ppm, greater than or equal to 40 wt ppm, greater than or equal to 45 wt ppm, greater than or equal to 50 wt ppm, greater than or equal to 55 wt ppm, greater than or equal to 60 wt ppm, greater than or equal to 65 wt ppm, greater than or equal to 70 wt ppm, greater than or equal to 75 wt ppm, greater than or equal to 80 wt ppm, or greater than or equal to 85 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 90 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 45 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 20 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Sr.

[0078] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Te in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Te in an amount of less than or equal to 15 wt ppm, less than or equal to 14.5 wt ppm, less than or equal to 14 wt ppm, less than or equal to 13.5 wt ppm, less than or equal to 13 wt ppm, less than or equal to 12.5 wt ppm, less than or equal to 12 wt ppm, less than or equal to 11.5 wt ppm, less than or equal to 11 wt ppm, less than or equal to 10.5 wt ppm, less than or equal to 10 wt ppm, less than or equal to 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Te in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, greater than or equal to 9.5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 10.5 wt ppm, greater than or equal to 11 wt ppm, greater than or equal to 11.5 wt ppm, greater than or equal to 12 wt ppm, greater than or equal to 12.5 wt ppm, greater than or equal to 13 wt ppm, greater than or equal to 13.5 wt ppm, greater than or equal to 14 wt ppm, or greater than or equal to 14.5 wt ppm.

[0079] Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 15 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 7.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 4.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Te.

[0080] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Zr in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Zr in an amount of less than or equal to 10 wt ppm, less than or equal to 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Zr in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, or greater than or equal to 9.5 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 10 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 4.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 2.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Zr.

[0081] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Co in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Co in an amount of less than or equal to 5 wt ppm, less than or equal to 4.8 wt ppm, less than or equal to 4.6 wt ppm, less than or equal to 4.4 wt ppm, less than or equal to 4.2 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.8 wt ppm, less than or equal to 3.6 wt ppm, less than or equal to 3.4 wt ppm, less than or equal to 3.2 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.8 wt ppm, less than or equal to 2.6 wt ppm, less than or equal to 2.4 wt ppm, less than or equal to 2.2 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.8 wt ppm, less than or equal to 1.6 wt ppm, less than or equal to 1.4 wt ppm, less than or equal to 1.2 wt ppm, less than or equal to 1 wt ppm, less than or equal to 0.8 wt ppm, less than or equal to 0.6 wt ppm, less than or equal to 0.4 wt ppm, or less than or equal to 0.2 wt ppm. In some embodiments, a glass fiber comprises Co in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.2 wt ppm, greater than or equal to 0.4 wt ppm, greater than or equal to 0.6 wt ppm, greater than or equal to 0.8 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.2 wt ppm, greater than or equal to 1.4 wt ppm, greater than or equal to 1.6 wt ppm, greater than or equal to 1.8 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.2 wt ppm, greater than or equal to 2.4 wt ppm, greater than or equal to 2.6 wt ppm, greater than or equal to 2.8 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.2 wt ppm, greater than or equal to

[0082] 3.4 wt ppm, greater than or equal to 3.6 wt ppm, greater than or equal to 3.8 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.2 wt ppm, greater than or equal to 4.4 wt ppm, greater than or equal to 4.6 wt ppm, or greater than or equal to 4.8 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 5 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 2 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to

[0083] 1.4 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Co.

[0084] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Cr in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Cr in an amount of less than or equal to 15 wt ppm, less than or equal to 14.5 wt ppm, less than or equal to 14 wt ppm, less than or equal to 13.5 wt ppm, less than or equal to 13 wt ppm, less than or equal to 12.5 wt ppm, less than or equal to 12 wt ppm, less than or equal to 11.5 wt ppm, less than or equal to 11 wt ppm, less than or equal to 10.5 wt ppm, less than or equal to 10 wt ppm, less than or equal to 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Cr in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, greater than or equal to 9.5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 10.5 wt ppm, greater than or equal to 11 wt ppm, greater than or equal to 11.5 wt ppm, greater than or equal to 12 wt ppm, greater than or equal to 12.5 wt ppm, greater than or equal to 13 wt ppm, greater than or equal to 13.5 wt ppm, greater than or equal to 14 wt ppm, or greater than or equal to 14.5 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 15 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 8.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 5.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Cr.

[0085] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Cu in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Cu in an amount of less than or equal to 5 wt ppm, less than or equal to 4.8 wt ppm, less than or equal to 4.6 wt ppm, less than or equal to 4.4 wt ppm, less than or equal to 4.2 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.8 wt ppm, less than or equal to 3.6 wt ppm, less than or equal to 3.4 wt ppm, less than or equal to 3.2 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.8 wt ppm, less than or equal to 2.6 wt ppm, less than or equal to 2.4 wt ppm, less than or equal to 2.2 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.8 wt ppm, less than or equal to 1.6 wt ppm, less than or equal to 1.4 wt ppm, less than or equal to 1.2 wt ppm, less than or equal to 1 wt ppm, less than or equal to 0.8 wt ppm, less than or equal to 0.6 wt ppm, less than or equal to 0.4 wt ppm, or less than or equal to 0.2 wt ppm. In some embodiments, a glass fiber comprises Cu in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.2 wt ppm, greater than or equal to 0.4 wt ppm, greater than or equal to 0.6 wt ppm, greater than or equal to 0.8 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.2 wt ppm, greater than or equal to 1.4 wt ppm, greater than or equal to 1.6 wt ppm, greater than or equal to 1.8 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.2 wt ppm, greater than or equal to 2.4 wt ppm, greater than or equal to 2.6 wt ppm, greater than or equal to 2.8 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.2 wt ppm, greater than or equal to 3.4 wt ppm, greater than or equal to 3.6 wt ppm, greater than or equal to 3.8 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.2 wt ppm, greater than or equal to 4.4 wt ppm, greater than or equal to 4.6 wt ppm, or greater than or equal to 4.8 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 5 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 1.6 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 1 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Cu.

[0086] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Fe in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Fe in an amount of less than or equal to 150 wt ppm, less than or equal to 145 wt ppm, less than or equal to 140 wt ppm, less than or equal to 135 wt ppm, less than or equal to 130 wt ppm, less than or equal to 125 wt ppm, less than or equal to 120 wt ppm, less than or equal to 115 wt ppm, less than or equal to 110 wt ppm, less than or equal to 105 wt ppm, less than or equal to 100 wt ppm, less than or equal to 95 wt ppm, less than or equal to 90 wt ppm, less than or equal to 85 wt ppm, less than or equal to 80 wt ppm, less than or equal to 75 wt ppm, less than or equal to 70 wt ppm, less than or equal to 65 wt ppm, less than or equal to 60 wt ppm, less than or equal to 55 wt ppm, less than or equal to 50 wt ppm, less than or equal to 45 wt ppm, less than or equal to 40 wt ppm, less than or equal to 35 wt ppm, less than or equal to 30 wt ppm, less than or equal to 25 wt ppm, less than or equal to 20 wt ppm, less than or equal to 15 wt ppm, less than or equal to 10 wt ppm, or less than or equal to 5 wt ppm. In some embodiments, a glass fiber comprises Fe in an amount of greater than or equal to 0 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 15 wt ppm, greater than or equal to 20 wt ppm, greater than or equal to 25 wt ppm, greater than or equal to 30 wt ppm, greater than or equal to 35 wt ppm, greater than or equal to 40 wt ppm, greater than or equal to 45 wt ppm, greater than or equal to 50 wt ppm, greater than or equal to 55 wt ppm, greater than or equal to 60 wt ppm, greater than or equal to 65 wt ppm, greater than or equal to 70 wt ppm, greater than or equal to 75 wt ppm, greater than or equal to 80 wt ppm, greater than or equal to 85 wt ppm, greater than or equal to 90 wt ppm, greater than or equal to 95 wt ppm, greater than or equal to 100 wt ppm, greater than or equal to 105 wt ppm, greater than or equal to 110 wt ppm, greater than or equal to 115 wt ppm, greater than or equal to 120 wt ppm, greater than or equal to 125 wt ppm, greater than or equal to 130 wt ppm, greater than or equal to 135 wt ppm, greater than or equal to 140 wt ppm, or greater than or equal to 145 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 150 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 70 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 35 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Fe.

[0087] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Mn in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Mn in an amount of less than or equal to 10 wt ppm, less than or equal to 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Mn in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, or greater than or equal to 9.5 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 10 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 3.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 2.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Mn. A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Ni in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Ni in an amount of less than or equal to 5 wt ppm, less than or equal to 4.8 wt ppm, less than or equal to 4.6 wt ppm, less than or equal to

[0088] 4.4 wt ppm, less than or equal to 4.2 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.8 wt ppm, less than or equal to 3.6 wt ppm, less than or equal to 3.4 wt ppm, less than or equal to 3.2 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.8 wt ppm, less than or equal to 2.6 wt ppm, less than or equal to 2.4 wt ppm, less than or equal to 2.2 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.8 wt ppm, less than or equal to 1.6 wt ppm, less than or equal to 1.4 wt ppm, less than or equal to 1.2 wt ppm, less than or equal to 1 wt ppm, less than or equal to 0.8 wt ppm, less than or equal to 0.6 wt ppm, less than or equal to 0.4 wt ppm, or less than or equal to 0.2 wt ppm. In some embodiments, a glass fiber comprises Ni in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.2 wt ppm, greater than or equal to 0.4 wt ppm, greater than or equal to 0.6 wt ppm, greater than or equal to 0.8 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.2 wt ppm, greater than or equal to 1.4 wt ppm, greater than or equal to 1.6 wt ppm, greater than or equal to 1.8 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.2 wt ppm, greater than or equal to 2.4 wt ppm, greater than or equal to 2.6 wt ppm, greater than or equal to 2.8 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.2 wt ppm, greater than or equal to

[0089] 3.4 wt ppm, greater than or equal to 3.6 wt ppm, greater than or equal to 3.8 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.2 wt ppm, greater than or equal to 4.4 wt ppm, greater than or equal to 4.6 wt ppm, or greater than or equal to 4.8 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 5 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 2.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 1.5 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Ni.

[0090] A glass fiber (e.g., a microglass fiber, a chopped strand glass fiber) described herein may comprise Ti in any of a variety of suitable proportions. In some embodiments, a glass fiber comprises Ti in an amount of less than or equal to 15 wt ppm, less than or equal to 14.5 wt ppm, less than or equal to 14 wt ppm, less than or equal to 13.5 wt ppm, less than or equal to 13 wt ppm, less than or equal to 12.5 wt ppm, less than or equal to 12 wt ppm, less than or equal to 11.5 wt ppm, less than or equal to 11 wt ppm, less than or equal to 10.5 wt ppm, less than or equal to 10 wt ppm, less than or equal to

[0091] 9.5 wt ppm, less than or equal to 9 wt ppm, less than or equal to 8.5 wt ppm, less than or equal to 8 wt ppm, less than or equal to 7.5 wt ppm, less than or equal to 7 wt ppm, less than or equal to 6.5 wt ppm, less than or equal to 6 wt ppm, less than or equal to 5.5 wt ppm, less than or equal to 5 wt ppm, less than or equal to 4.5 wt ppm, less than or equal to 4 wt ppm, less than or equal to 3.5 wt ppm, less than or equal to 3 wt ppm, less than or equal to 2.5 wt ppm, less than or equal to 2 wt ppm, less than or equal to 1.5 wt ppm, less than or equal to 1 wt ppm, or less than or equal to 0.5 wt ppm. In some embodiments, a glass fiber comprises Ti in an amount of greater than or equal to 0 wt ppm, greater than or equal to 0.5 wt ppm, greater than or equal to 1 wt ppm, greater than or equal to 1.5 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 2.5 wt ppm, greater than or equal to 3 wt ppm, greater than or equal to 3.5 wt ppm, greater than or equal to 4 wt ppm, greater than or equal to 4.5 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 5.5 wt ppm, greater than or equal to 6 wt ppm, greater than or equal to 6.5 wt ppm, greater than or equal to 7 wt ppm, greater than or equal to 7.5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 8.5 wt ppm, greater than or equal to 9 wt ppm, greater than or equal to 9.5 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 10.5 wt ppm, greater than or equal to 11 wt ppm, greater than or equal to

[0092] 11.5 wt ppm, greater than or equal to 12 wt ppm, greater than or equal to 12.5 wt ppm, greater than or equal to 13 wt ppm, greater than or equal to 13.5 wt ppm, greater than or equal to 14 wt ppm, or greater than or equal to 14.5 wt ppm. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 15 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 6.5 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 4 wt ppm). Other ranges are also possible. In some embodiments, a glass fiber does not comprise Ti.

[0093] It should, of course, be understood that a plurality of glass fibers described herein (e.g., a first plurality of glass fibers, a second plurality of glass fibers) may be a plurality of glass fibers having an impurity concentration within the above-mentioned ranges. In embodiments wherein an electrode media comprises multiple pluralities of glass fibers, it should be understood that, in some embodiments, each plurality of glass fibers may independently have an impurity concentration within the above-mentioned ranges. For example, a first plurality of glass fibers (e.g., a plurality of microglass fibers) may have a first impurity concentration within the above-mentioned ranges, while a second plurality of glass fibers (e.g., a plurality of chopped strand glass fibers) may have a second impurity concentration within the above-mentioned ranges. The second impurity concentration may be the same as the first impurity concentration, or may differ from the first impurity concentration, depending on the embodiment.

[0094] As described above, in some embodiments a fiber web comprises a first plurality of glass fibers and another plurality of fibers that is different from the first plurality of glass fibers. In some embodiments, a plurality of fibers (e.g., a second, third, fourth, fifth, sixth, seventh, or eighth plurality of fibers) of the fiber web is a plurality of staple fibers. Staple fibers may be cut (e.g., from a filament) or formed as non-continuous discrete fibers to have a particular length or a range of lengths as described in more detail herein. Staple fibers may be configured to mechanically and / or thermally reinforce the fiber web. For example, staple fibers may be used to control stiffness, strength, density and / or plasticity and / or thermal stability of the fiber web. Increasing the relative amount of staple fibers may, in some embodiments, increase the density and the relative pore size of the fiber web, as well as its strength and elasticity. However, increasing the relative amount of staple fibers may decrease machinability, elongation and break, and compressibility of the fiber web, according to some embodiments. The staple fibers may have any of a variety of general physical characteristics. For example, the staple fibers may be relatively straight, in some embodiments.

[0095] Staple fibers (e.g., a second plurality of fibers comprising staple fibers) may be formed from any of a variety of suitable materials, and made using any of a variety of suitable methods. For example, in some embodiments, a plurality of staple fibers is a plurality of glass fibers. A plurality of staple fibers may be a plurality of drawn glass fibers, in some embodiments. For example, staple glass fibers may be formed by drawing a melt of glass from bushing tips and then subjecting the drawn melt of glass to subjected to flame blowing or rotary spinning (e.g., centrifugal spinning) processes. According to some embodiments, a plurality of staple fibers is not a plurality of blown glass fibers. In some embodiments, a plurality of staple fibers is a plurality of non-glass fibers. For example, a plurality of staple fibers may be a plurality of conductive fibers such as carbon fibers. According to some embodiments, a plurality of staple fibers is formed by chopping longer fibers to a desired length (e.g., a plurality of staple fibers may be a plurality of chopped strand glass fibers or a plurality of chopped strand carbon fibers). In some embodiments, a plurality of staple fibers is a plurality of non-chopped fibers.

[0096] A fiber web (e.g., a non-woven fiber web) described herein may comprise a plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) in any of a variety of suitable amounts. In some embodiments, a plurality of staple fibers makes up greater than or equal to greater than or equal to 0 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, greater than or equal to 45 wt%, greater than or equal to 50 wt%, greater than or equal to 55 wt%, greater than or equal to 60 wt%, greater than or equal to 65 wt%, greater than or equal to 70 wt%, greater than or equal to 75 wt%, greater than or equal to 80 wt%, or greater than or equal to 85 wt%, and / or less than or equal to 90 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) makes up less than or equal to 90 wt%, less than or equal to 85 wt%, less than or equal to 80 wt%, less than or equal to 75 wt%, less than or equal to 70 wt%, less than or equal to 65 wt%, less than or equal to 60 wt%, less than or equal to 55 wt%, less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 90 wt%, greater than or equal to 10 wt% and less than or equal to 50 wt%, or greater than or equal to 20 wt% and less than or equal to 40 wt%). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited. Staple fibers may have any of a variety of suitable geometries. For example, a plurality of staple fibers may be a second plurality of glass fibers (e.g., a second plurality of glass fibers that are chopped strand glass fibers) having an average length or an average diameter within one of the ranges mentioned above. More generally, staple fibers such as staple glass fibers or staple carbon fibers may have any of a variety of suitable diameters and lengths, as described below. It should, of course, be understood that the ranges below may be appropriate for staple fibers of any of a variety of suitable compositions, including staple glass fibers, and that a plurality of staple glass fibers need not have a length or diameter within one of the ranges mentioned above.

[0097] A plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) described herein may have any of a variety of suitable average diameters. In some embodiments, a plurality of staple fibers has an average diameter of greater than or equal to 1 micron, greater than or equal to 2 microns, greater than or equal to 4 microns, greater than or equal to 6 microns, greater than or equal to 8 microns, greater than or equal to 10 microns, greater than or equal to 12 microns, greater than or equal to 14 microns, greater than or equal to 16 microns, greater than or equal to 18 microns, greater than or equal to 20 microns, greater than or equal to 22 microns, greater than or equal to 24 microns, greater than or equal to 26 microns, or greater than or equal to 28 microns, and / or less than or equal to 30 microns. In some embodiments, a plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) has an average diameter of less than or equal to 30 microns, less than or equal to 28 microns, less than or equal to 26 microns, less than or equal to 24 microns, less than or equal to 22 microns, less than or equal to 20 microns, less than or equal to 18 microns, less than or equal to 16 microns, less than or equal to 14 microns, less than or equal to 12 microns, less than or equal to 10 microns, less than or equal to 8 microns, less than or equal to 6 microns, less than or equal to 4 microns, or less than or equal to 2 microns, and / or greater than or equal to 1 micron. Combinations of these ranges are also possible (e.g., greater than or equal to 5 microns and less than or equal to 25 microns, greater than or equal to 10 microns and less than or equal to 20 microns, or greater than or equal to 12 microns and less than or equal to 16 microns). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0098] The average diameter of the second plurality of fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0099] A plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) described herein may have any of a variety of suitable average lengths. In some embodiments, a plurality of staple fibers has an average length of greater than or equal to 2 mm, greater than or equal to 5 mm, greater than or equal to 7 mm, greater than or equal to 10 mm, greater than or equal to 12 mm, greater than or equal to 15 mm, greater than or equal to 17 mm, greater than or equal to 20 mm, greater than or equal to 22 mm, greater than or equal to 25 mm, greater than or equal to 27 mm, greater than or equal to 30 mm, greater than or equal to 32 mm, greater than or equal to 35 mm, greater than or equal to 37 mm, greater than or equal to 40 mm, greater than or equal to 42 mm, greater than or equal to 45 mm, greater than or equal to 47 mm, greater than or equal to 50 mm, greater than or equal to 75 mm, greater than or equal to 100 mm, greater than or equal to 125 mm, greater than or equal to 150 mm, greater than or equal to 175 mm, greater than or equal to 200 mm, greater than or equal to 225 mm, greater than or equal to 250 mm, or greater than or equal to 275 mm, and / or less than or equal to 300 mm. In some embodiments, a plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) has an average length of less than or equal to 300 mm, less than or equal to 275 mm, less than or equal to 250 mm, less than or equal to 225 mm, less than or equal to 200 mm, less than or equal to 175 mm, less than or equal to 150 mm, less than or equal to 125 mm, less than or equal to 100 mm, less than or equal to 75 mm, less than or equal to 50 mm, less than or equal to 47 mm, less than or equal to 45 mm, less than or equal to 42 mm, less than or equal to 40 mm, less than or equal to 37 mm, less than or equal to 35 mm, less than or equal to 32 mm, less than or equal to 30 mm, less than or equal to 27 mm, less than or equal to 25 mm, less than or equal to 22 mm, less than or equal to 20 mm, less than or equal to 17 mm, less than or equal to 15 mm, less than or equal to 12 mm, less than or equal to 10 mm, less than or equal to 7 mm, or less than or equal to 5 mm, and / or greater than or equal to 2 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 2 mm and less than or equal to 300 mm, greater than or equal to 5 mm and less than or equal to 20 mm, or greater than or equal to 10 mm and less than or equal to 15 mm). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0100] The average length of the second plurality of fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0101] A plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) may have any of a variety of suitable length distributions. A plurality of staple fibers (e.g., a plurality of chopped strand glass fibers, a plurality of chopped carbon fibers) has a length distribution distributed symmetrically around the average length, in some embodiments. For example, the length of a plurality of staple fibers may be normally distributed, e.g., as the result of a chopping or drawing process. In some embodiments, it may be advantageous for staple fibers to have a symmetric distribution around the average length of the fibers (e.g., a normal length distribution).

[0102] The length distribution of a plurality of fibers (e.g., a plurality of staple fibers) may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0103] A plurality of fibers with an asymmetric length distribution may have a median fiber length that differs from an average fiber length in some (but not necessarily all) embodiments. Therefore, in some embodiments a plurality of staple fibers may be characterized by the similarity between the median fiber length of a plurality and the average fiber length of the staple fibers of the plurality of staple fibers. A plurality of staple fibers (e.g., a second plurality of fibers comprising staple fibers) described herein may have any of a variety of suitable similarities between the median fiber length and the average fiber length of the plurality of staple fibers. According to some embodiments, a plurality of staple fibers has a median fiber length that differs from an average fiber length of the plurality of staple fibers by less than or equal to 20%, less than or equal to 18%, less than or equal to 15% less than or equal to 12%, less than or equal to 10%, less than or equal to 8%, less than or equal to 5%, less than or equal to 2%, or less than or equal to 1% of the average length of the fibers of the plurality. In some embodiments, a plurality of staple fibers has a median fiber length that differs from an average fiber length of the plurality of staple fibers by greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 5%, greater than or equal to 8%, greater than or equal to 10%, greater than or equal to 12%, greater than or equal to 15%, or greater than or equal to 18%, and / or less than or equal to 20% of the average length of the fibers of the plurality. Combinations of these ranges are also possible (e.g., greater than or equal to 0% and less than or equal to 20%, greater than or equal to 0% and less than or equal to 10%, or greater than or equal to 0% and less than or equal to 5%). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0104] The difference between the median fiber length and the average fiber length may be measured by using a Diamscope and measuring at least 10,000 fibers to determine the median fiber length and the average fiber length. A difference between the median fiber length and the average fiber length may then be determined by taking the absolute value of the quantity: (average fiber length - median fiber length) / average fiber length x 100%. If the plurality of fibers has an average length of greater than or equal to 500 microns, the difference between the median fiber length and the average fiber length may instead be measured using other techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0105] A fiber web may comprise one or more pluralities of non-glass fibers. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are non-glass fibers. A fiber web described herein may comprise non-glass fibers in any of a variety of suitable weight percentages. In some embodiments, a plurality of non-glass fibers (e.g., a second plurality of fibers comprising non-glass fibers) makes up greater than or equal to 0 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, greater than or equal to 45 wt%, greater than or equal to 50 wt%, greater than or equal to 55 wt%, greater than or equal to 60 wt%, greater than or equal to 65 wt%, greater than or equal to 70 wt%, greater than or equal to 75 wt%, or greater than or equal to 80 wt%, and / or less than or equal to 85 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a plurality of non-glass fibers (e.g., a second plurality of fibers comprising non-glass fibers) makes up less than or equal to 85 wt%, less than or equal to 80 wt%, less than or equal to 75 wt%, less than or equal to 70 wt%, less than or equal to 65 wt%, less than or equal to 60 wt%, less than or equal to 55 wt%, less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 85 wt%, or greater than or equal to 0 wt% and less than or equal to 50 wt%). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0106] In some embodiments, a fiber web comprises a plurality of synthetic fibers. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are synthetic fibers. Synthetic fibers may comprise any of a variety of appropriate materials and particularly polymeric materials, particularly organic polymeric materials. For example, in some embodiments, a fiber web comprises a plurality of synthetic fibers that comprise one or more of a poly(olefin) (e.g., poly(propylene), poly (ethylene)), an acrylic (e.g., a dryspun acrylic, a modacrylic, a wetspun acrylic), a halogenated polymer (e.g., a fluorinated polymer, such as poly(vinyl chloride), poly(tetrafluoroethylene), and / or poly(vinylidine fluoride)), poly(styrene), poly (sulfone), poly(ethersulfone), a poly(carbonate), a poly(acrylonitrile) (e.g., an oxidized poly(acrylonitrile)), a nylon, a poly (urethane), a phenolic resin, a poly(ester), a poly(aramid) (e.g., a para-poly(aramid), a meta-poly(aramid), Kevlar, Nomex), a poly(imide), poly(phenylene oxide), poly(phenylene sulfide), poly(methyl pentene), poly(ether ketone), a liquid crystal polymer (e.g., poly(p-phenylene-2,6- benzobisoxazole; a poly(ester)-based liquid crystal polymer, such as a polymer produced by the polycondensation of 4-hydroxybenzoic acid and 6-hydroxynaphthalene-2- carboxylic acid), polyvinyl alcohol (PVA), regenerated cellulose, celluloid, cellulose acetate, and / or carboxy methylcellulose. A fiber web may comprise a plurality of monocomponent synthetic fibers and / or a plurality of multicomponent (e.g., bicomponent) synthetic fibers. Monocomponent fibers generally comprise one component. Non-limiting examples of suitable materials that may be advantageous for use in monocomponent synthetic fibers include, but are not limited to, polyvinyl alcohol (PVA), poly(olefin)s such as poly(ethylene), poly(propylene), and poly (butylene); polyesters and / or co-polyesters such as poly (ethylene terephthalate), co-poly (ethylene terephthalate), poly (butylene terephthalate), and poly(ethylene isophthalate); polyamides and co-polyamides such as nylons and aramids; and halogenated polymers such as poly(tetrafluoroethylene). Multicomponent fibers generally comprise two or more components having different chemical compositions from each other. Some or all components of a multicomponent fiber may be synthetic. Non-limiting examples of suitable materials that may be present in a component of a multicomponent fiber include poly(olefin)s such as poly(ethylene), poly(propylene), and poly (butylene); polyesters and / or co-polyesters such as poly (ethylene terephthalate), co-poly (ethylene terephthalate), poly (butylene terephthalate), and poly(ethylene isophthalate); polyamides and co-polyamides such as nylons and aramids; and halogenated polymers such as poly(tetrafluoroethylene). The synthetic fibers may, in some embodiments, be used to bind other fibers in a fiber- web (i.e., may be a synthetic binder fiber). For example, in some embodiments, a multicomponent fiber comprises a first component that melts to fuse fibers of the web while a second component of a multicomponent fiber remains rigid. As another example, in some embodiments, a synthetic binder fiber (e.g., a monocomponent synthetic binder fiber) comprises a thermoset polymer configured to melt upon initial heating, thereby fusing other fibers of a fiber web, e.g., such that when the melted polymer resolidifies it cannot be subsequently melted. Both approaches can be particularly useful for use in electrode media, where they can help provide strength and / or porosity to fiber webs to facilitate improved processing conditions.

[0107] According to some embodiments, the synthetic fibers are synthetic staple fibers.

[0108] In some embodiments, it has been recognized herein that monocomponent synthetic binder fibers (e.g., comprising PVA) can provide particular advantages for the strength and machinability of fiber webs without compromising pore size, making their use particularly advantageous. For example, in some embodiments, increasing the relative amount of monocomponent synthetic binder fibers (e.g., comprising PVA) can significantly increase the relative strength and machinability of the fiber web, while providing modest improvements in elasticity and compressability and a modest reductions in density. However, in some embodiments, increasing the relative amount of monocomponent synthetic binder fibers significantly decreases elongation at break. It has further been recognized that according to some embodiments, increasing the relative amount of multicomponent (e.g., bicomponent fibers) in the fiber web can increase relative strength and relative elongation at break without significantly impacting other properties of the fiber web. Accordingly, in some embodiments, the use of multicomponent (e.g., bicomponent) fibers in combination with monocomponent synthetic binder fibers (e.g., comprising PVA) may be particularly useful, since the monocomponent synthetic binder fibers can significantly improve machinability of the fiber web while the multicomponent fibers hedge against the reduction in elongation at break.

[0109] When present, multicomponent fibers may have a variety of suitable structures. In some embodiments, the multicomponent fibers comprise bicomponent fibers (i.e., fibers having two components). Bicomponent fibers may have a variety of suitable structures, such as core / sheath fibers (e.g., concentric core / sheath fibers, non-concentric core / sheath fibers), segmented pie fibers, split fibers, side-by-side fibers, tip-trilobal fibers, and “island in the sea” fibers. In some embodiments, a fiber web comprises a plurality of multicomponent fibers that initially had one of the above-referenced structures, but underwent a process (e.g., a splitting process) during fabrication of the fiber web to form a different structure. By way of example, some fiber webs may comprise fibers that were initially bicomponent fibers but were split during fiber web fabrication to form finer fibers.

[0110] When core / sheath bicomponent fibers are present, the sheath may have a lower melting temperature than the core. When heated, the sheath may melt prior to the core, binding other fibers within the fiber web together while the core remains solid. Nonlimiting examples of suitable bicomponent fibers, in which the component with the lower melting temperature is listed first and the component with the higher melting temperature is listed second, include the following: poly(ethylene) / poly(ethylene terephthalate), poly(propylene) / poly(ethylene terephthalate), co-poly(ethylene terephthalate) / poly(ethylene terephthalate), poly(butylene terephthalate) / poly(ethylene terephthalate), co-polyamide / polyamide, and poly (ethylene) / poly (propylene).

[0111] Without wishing to be bound by any theory, it is believed that, in some instances, inclusion of multicomponent (e.g., bicomponent) fibers in a fiber web increases the tensile strength and / or durability compared to a fiber web without multicomponent fibers, all other factors being equal. An advantage of the use of multicomponent fibers in electrode media is that, in some embodiments, the use of multicomponent fibers reduces or eliminates the disadvantages associated with using polymeric resins to prepare fiber webs, allowing the preparation of mechanically robust fiber webs with larger pores and lower densities than might be achieved using a resinous fiber web. For example, multicomponent fibers may be used to bind pluralities of fibers in the fiber web (e.g., via adhesion between the multicomponent fibers and other pluralities of fibers of the fiber web). Multicomponent fibers may thus be used to control the mechanical properties (e.g., the dry strength, the plasticity) of a fiber web, in some embodiments.

[0112] As discussed in greater detail below, in some embodiments synthetic fibers such as multicomponent fibers are damaged or destroyed in at least a portion of a fiber web during formation of the fiber web into an electrode media. In some embodiments, a fiber web used in an electrode media described herein may have a non-uniform distribution of synthetic (e.g., multicomponent) fibers. For example, in some embodiments, a fiber web comprises a plurality of synthetic fibers but has an edge portion of the fiber web that does not include synthetic fibers (e.g., since the synthetic fibers at the edge portion may be burned off during lug formation on the edge portion of the fiber web, while other fibers of the edge portion, such as glass fibers, remain intact). In some embodiments, a fiber web described herein has a mass gradient of synthetic fibers along at least a portion of a major surface of the fiber web. The lug formation process is described in greater detail below.

[0113] In some embodiments, a fiber web comprises a plurality of multicomponent fibers. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are multicomponent fibers. A plurality of multicomponent fibers may make up any of a variety of suitable proportions of a fiber web (e.g., a non-woven fiber web) described herein. In some embodiments, a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) makes up greater than or equal to 0 wt%, greater than or equal to 1 wt%, greater than or equal to 2 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, or greater than or equal to 45 wt%, and / or less than or equal to 50 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) makes up less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, less than or equal to 5 wt%, less than or equal to 2 wt%, or less than or equal to 1 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 50 wt%, greater than or equal to 5 wt% and less than or equal to 30 wt%, or greater than or equal to 10 wt% and less than or equal to 20 wt%). Other ranges are also possible.

[0114] Multicomponent fibers described herein may have any of a variety of suitable average diameters. In some embodiments, a fiber web comprises a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) having an average diameter of greater than or equal to 5 microns, greater than or equal to 6 microns, greater than or equal to 7 microns, greater than or equal to 8 microns, greater than or equal to 9 microns, greater than or equal to 10 microns, greater than or equal to 11 microns, greater than or equal to 12 microns, greater than or equal to 13 microns, greater than or equal to 14 microns, greater than or equal to 15 microns, greater than or equal to 16 microns, greater than or equal to 17 microns, greater than or equal to 18 microns, greater than or equal to 19 microns, greater than or equal to 20 microns, greater than or equal to 21 microns, greater than or equal to 22 microns, greater than or equal to 23 microns, or greater than or equal to 24 microns, and / or less than or equal to 25 microns. In some embodiments, a fiber web comprises a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) having an average diameter of less than or equal to 25 microns, less than or equal to 24 microns, less than or equal to 23 microns, less than or equal to 22 microns, less than or equal to 21 microns, less than or equal to 20 microns, less than or equal to 19 microns, less than or equal to 18 microns, less than or equal to 17 microns, less than or equal to 16 microns, less than or equal to 15 microns, less than or equal to 14 microns, less than or equal to 13 microns, less than or equal to 12 microns, less than or equal to 11 microns, less than or equal to 10 microns, less than or equal to 9 microns, less than or equal to 8 microns, less than or equal to 7 microns, or less than or equal to 6 microns, and / or greater than or equal to 5 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 5 microns and less than or equal to 25 microns, greater than or equal to 10 microns and less than or equal to 20 microns, or greater than or equal to 12 microns and less than or equal to 16 microns). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0115] The average diameter of a plurality of multicomponent fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0116] According to some embodiments, a plurality of synthetic fibers is a plurality of synthetic binder fibers (e.g., a plurality of synthetic monocomponent fibers, such as PVA fibers). In some embodiments, a plurality of synthetic binder fibers of a fiber web has an average diameter of greater than or equal to 0.2 microns, greater than or equal to 1.0 micron, greater than or equal to 5.0 microns, greater than or equal to 10.0 microns, greater than or equal to 15.0 microns, greater than or equal to 20.0 microns, or greater than or equal to 25.0 microns, greater than or equal to 30.0 microns, greater than or equal to 40.0 microns, and / or less than or equal to 50.0 microns. In some embodiments, the plurality of synthetic binder fibers has an average diameter of less than or equal to 50.0 microns, less than or equal to 40.0 microns, less than or equal to 30.0 microns, less than or equal to 25.0 microns, less than or equal to 20.0 microns, less than or equal to 15.0 microns, less than or equal to 10.0 microns, less than or equal to 5.0 microns, less than or equal to 1.0 micron, or less than or equal to 0.5 microns, and / or greater than or equal to 0.2 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.2 microns and less than or equal to 50.0 microns). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0117] The average diameter of a plurality of synthetic fibers (e.g., synthetic binder fibers) may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0118] Multicomponent fibers described herein may have any of a variety of suitable average lengths. In some embodiments, a fiber web comprises a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) having an average length of greater than or equal to 2 mm, greater than or equal to 3 mm, greater than or equal to 4 mm, greater than or equal to 5 mm, greater than or equal to 6 mm, greater than or equal to 7 mm, greater than or equal to 8 mm, greater than or equal to 9 mm, greater than or equal to 10 mm, greater than or equal to 11 mm, greater than or equal to 12 mm, greater than or equal to 13 mm, greater than or equal to 14 mm, greater than or equal to 15 mm, greater than or equal to 16 mm, greater than or equal to 17 mm, greater than or equal to 18 mm, greater than or equal to 19 mm, greater than or equal to 20 mm, greater than or equal to 21 mm, greater than or equal to 22 mm, greater than or equal to 23 mm, or greater than or equal to 24 mm, and / or less than or equal to 25 mm. In some embodiments, a fiber web comprises a plurality of multicomponent fibers (e.g., a second plurality of fibers comprising multicomponent fibers) having an average length of less than or equal to 25 mm, less than or equal to 24 mm, less than or equal to 23 mm, less than or equal to 22 mm, less than or equal to 21 mm, less than or equal to 20 mm, less than or equal to 19 mm, less than or equal to 18 mm, less than or equal to 17 mm, less than or equal to 16 mm, less than or equal to 15 mm, less than or equal to 14 mm, less than or equal to 13 mm, less than or equal to 12 mm, less than or equal to 11 mm, less than or equal to 10 mm, less than or equal to 9 mm, less than or equal to 8 mm, less than or equal to 7 mm, less than or equal to 6 mm, less than or equal to 5 mm, less than or equal to 4 mm, or less than or equal to 3 mm, and / or greater than or equal to 2 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 2 mm and less than or equal to 25 mm, greater than or equal to 5 mm and less than or equal to 20 mm, or greater than or equal to 10 mm and less than or equal to 15 mm). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0119] The average length of a plurality of multicomponent fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0120] Likewise, synthetic fibers described herein (e.g., monocomponent fibers, synthetic binder fibers) may have any of a variety of suitable average lengths. In some embodiments, a fiber web comprises a plurality of synthetic fibers (e.g., a second plurality of fibers comprising synthetic binder fibers) having an average length of greater than or equal to 0.1 mm, greater than or equal to 0.5 mm, greater than or equal to 1 mm, greater than or equal to 2 mm, greater than or equal to 3 mm, greater than or equal to 4 mm, greater than or equal to 5 mm, greater than or equal to 6 mm, greater than or equal to 7 mm, greater than or equal to 8 mm, greater than or equal to 9 mm, greater than or equal to 10 mm, greater than or equal to 11 mm, greater than or equal to 12 mm, greater than or equal to 13 mm, greater than or equal to 14 mm, greater than or equal to 15 mm, greater than or equal to 16 mm, greater than or equal to 17 mm, greater than or equal to 18 mm, greater than or equal to 19 mm, greater than or equal to 20 mm, greater than or equal to 21 mm, greater than or equal to 22 mm, greater than or equal to 23 mm, or greater than or equal to 24 mm, and / or less than or equal to 25 mm. In some embodiments, a fiber web comprises a plurality of synthetic fibers (e.g., a second plurality of fibers comprising synthetic binder fibers) having an average length of less than or equal to 25 mm, less than or equal to 24 mm, less than or equal to 23 mm, less than or equal to 22 mm, less than or equal to 21 mm, less than or equal to 20 mm, less than or equal to 19 mm, less than or equal to 18 mm, less than or equal to 17 mm, less than or equal to 16 mm, less than or equal to 15 mm, less than or equal to 14 mm, less than or equal to 13 mm, less than or equal to 12 mm, less than or equal to 11 mm, less than or equal to 10 mm, less than or equal to 9 mm, less than or equal to 8 mm, less than or equal to 7 mm, less than or equal to 6 mm, less than or equal to 5 mm, less than or equal to 4 mm, less than or equal to 3 mm, less than or equal to 2 mm, less than or equal to 1 mm, less than or equal to 0.5 mm, and / or greater than or equal to 0.1 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 0.1 mm and less than or equal to 25 mm, greater than or equal to 1 mm and less than or equal to 10 mm, or greater than or equal to 1 mm and less than or equal to 5 mm). Other ranges are also possible.

[0121] The average length of a plurality of synthetic fibers (e.g., monocomponent fibers, synthetic binder fibers) may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM). In some embodiments, a fiber web described herein comprises a plurality of natural fibers. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are natural fibers. In some embodiments, the natural fibers comprise natural cellulose fibers, such as cellulose wood (e.g., cedar), softwood fibers, and / or hardwood fibers. Exemplary softwood fibers include fibers obtained from mercerized southern pine (“mercerized southern pine fibers or HPZ fibers”), northern bleached softwood kraft (e.g., fibers obtained from Robur Flash (“Robur Flash fibers”)), southern bleached softwood kraft (e.g., fibers obtained from Brunswick pine (“Brunswick pine fibers”)), or chemically treated mechanical pulps (“CTMP fibers”). For example, HPZ fibers can be obtained from Buckeye Technologies, Inc., Memphis, TN; Robur Flash fibers can be obtained from Rottneros AB, Stockholm, Sweden; and Brunswick pine fibers can be obtained from Georgia-Pacific, Atlanta, GA. Exemplary hardwood fibers include fibers obtained from Eucalyptus (“Eucalyptus fibers”). Eucalyptus fibers are commercially available from, e.g., (1) Suzano Group, Suzano, Brazil (“Suzano fibers”), (2) Group Portucel Soporcel, Cacia, Portugal (“Cacia fibers”), (3) Tembec, Inc., Temiscaming, QC, Canada (“Tarascon fibers”), (4) Kartonimex Intercell, Duesseldorf, Germany, (“Acacia fibers”), (5) Mead-Westvaco, Stamford, CT (“Westvaco fibers”), and (6) Georgia- Pacific, Atlanta, GA (“Leaf River fibers”). Natural fibers, when present, may comprise fibrillated natural cellulose fibers, and / or may comprise unfibrillated natural cellulose fibers.

[0122] As discussed in greater detail below, in some embodiments natural fibers are damaged or destroyed in at least a portion of a fiber web during formation of the fiber web into an electrode media. In some embodiments, a fiber web used in an electrode media described herein may have a non-uniform distribution of natural fibers. For example, in some embodiments, a fiber web comprises a plurality of natural fibers but has an edge portion of the fiber web that does not include natural fibers (e.g., since the natural fibers at the edge portion may be burned off during lug formation on the edge portion of the fiber web, while other fibers of the edge portion, such as glass fibers, remain intact). In some embodiments, a fiber web described herein has a mass gradient of natural fibers along at least a portion of a major surface of the fiber web. The lug formation process is described in greater detail below.

[0123] A fiber web (e.g., a non-woven fiber web) described herein may comprise fibrillated fibers. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are fibrillated fibers. The fibrillated fibers may be natural or synthetic. For example, the fibrillated fibers may comprise fibrillated natural cellulose or fibrillated synthetic cellulose. A plurality of fibrillated fibers may make up any of a variety of suitable proportions of a fiber web (e.g., a nonwoven fiber web) described herein. In some embodiments, a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) makes up greater than or equal to 0 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, or greater than or equal to 45 wt%, and / or less than or equal to 50 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) makes up less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 50 wt%, greater than or equal to 5 wt% and less than or equal to 30 wt%, or greater than or equal to 10 wt% and less than or equal to 20 wt%). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0124] Fibrillated fibers described herein may have any of a variety of suitable average diameters. In some embodiments, a fiber web comprises a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) having an average diameter of greater than or equal to 3 microns, greater than or equal to 5 microns, greater than or equal to 8 microns, greater than or equal to 10 microns, greater than or equal to 13 microns, greater than or equal to 15 microns, greater than or equal to 18 microns, greater than or equal to 20 microns, greater than or equal to 23 microns, greater than or equal to 25 microns, greater than or equal to 28 microns, greater than or equal to 30 microns, greater than or equal to 33 microns, greater than or equal to 35 microns, greater than or equal to 38 microns, greater than or equal to 40 microns, greater than or equal to 43 microns, greater than or equal to 45 microns, greater than or equal to 48 microns, greater than or equal to 50 microns, greater than or equal to 53 microns, greater than or equal to 55 microns, greater than or equal to 58 microns, greater than or equal to 60 microns, greater than or equal to 63 microns, greater than or equal to 65 microns, greater than or equal to 68 microns, greater than or equal to 70 microns, greater than or equal to 73 microns, greater than or equal to 75 microns, greater than or equal to 78 microns, greater than or equal to 80 microns, greater than or equal to 83 microns, greater than or equal to 85 microns, greater than or equal to 88 microns, greater than or equal to 90 microns, greater than or equal to 93 microns, greater than or equal to 95 microns, or greater than or equal to 98 microns, and / or less than or equal to 100 microns. In some embodiments, a fiber web comprises a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) having an average diameter of less than or equal to 100 microns, less than or equal to 98 microns, less than or equal to 95 microns, less than or equal to 93 microns, less than or equal to 90 microns, less than or equal to 88 microns, less than or equal to 85 microns, less than or equal to 83 microns, less than or equal to 80 microns, less than or equal to 78 microns, less than or equal to 75 microns, less than or equal to 73 microns, less than or equal to 70 microns, less than or equal to 68 microns, less than or equal to 65 microns, less than or equal to 63 microns, less than or equal to 60 microns, less than or equal to 58 microns, less than or equal to 55 microns, less than or equal to 53 microns, less than or equal to 50 microns, less than or equal to 48 microns, less than or equal to 45 microns, less than or equal to 43 microns, less than or equal to 40 microns, less than or equal to 38 microns, less than or equal to 35 microns, less than or equal to 33 microns, less than or equal to 30 microns, less than or equal to 28 microns, less than or equal to 25 microns, less than or equal to 23 microns, less than or equal to 20 microns, less than or equal to 18 microns, less than or equal to 15 microns, less than or equal to 13 microns, less than or equal to 10 microns, less than or equal to 8 microns, or less than or equal to 5 microns, and / or greater than or equal to 3 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 3 microns and less than or equal to 100 microns, greater than or equal to 5 microns and less than or equal to 30 microns, or greater than or equal to 10 microns and less than or equal to 20 microns). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0125] The average diameter of a plurality of fibrillated fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0126] Fibrillated fibers described herein may have any of a variety of suitable average lengths. In some embodiments, a fiber web comprises a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) having an average length of greater than or equal to 2 mm, greater than or equal to 3 mm, greater than or equal to 5 mm, greater than or equal to 7 mm, greater than or equal to 10 mm, greater than or equal to 12 mm, greater than or equal to 15 mm, greater than or equal to 17 mm, greater than or equal to 20 mm, greater than or equal to 22 mm, greater than or equal to 25 mm, greater than or equal to 27 mm, greater than or equal to 30 mm, greater than or equal to 32 mm, greater than or equal to 35 mm, greater than or equal to 37 mm, greater than or equal to 40 mm, greater than or equal to 42 mm, greater than or equal to 45 mm, or greater than or equal to 47 mm, and / or less than or equal to 50 mm. In some embodiments, a fiber web comprises a plurality of fibrillated fibers (e.g., a second plurality of fibers comprising fibrillated fibers) having an average length of less than or equal to 50 mm, less than or equal to 47 mm, less than or equal to 45 mm, less than or equal to 42 mm, less than or equal to 40 mm, less than or equal to 37 mm, less than or equal to 35 mm, less than or equal to 32 mm, less than or equal to 30 mm, less than or equal to 27 mm, less than or equal to 25 mm, less than or equal to 22 mm, less than or equal to 20 mm, less than or equal to 17 mm, less than or equal to 15 mm, less than or equal to 12 mm, less than or equal to 10 mm, less than or equal to 7 mm, less than or equal to 5 mm, or less than or equal to 3 mm, and / or greater than or equal to 2 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 2 mm and less than or equal to 50 mm, greater than or equal to 3 mm and less than or equal to 25 mm, or greater than or equal to 6 mm and less than or equal to 15 mm). Other ranges are also possible. It should, of course, be understood while these ranges may refer to a second plurality of fibers, as indicated, they may also be appropriate for a third, fourth, fifth, sixth, seventh, or eighth plurality of fibers, depending on the embodiment, as the disclosure is not so limited.

[0127] The average length of a plurality of fibrillated fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0128] The fibrillated fibers may have a variety of suitable Canadian Standard Freeness (CSF). For example, in some embodiments, the fibrillated fibers have an average of greater than or equal to 20 CSF, greater than or equal to 30 CSF, greater than or equal to 40 CSF, greater than or equal to 50 CSF, greater than or equal to 75 CSF, greater than or equal to 100 CSF, greater than or equal to 120 CSF, greater than or equal to 125 CSF, greater than or equal to 150 CSF, greater than or equal to 200 CSF, greater than or equal to 250 CSF, greater than or equal to 300 CSF, greater than or equal to 350 CSF, greater than or equal to 400 CSF, greater than or equal to 450 CSF, or greater than or equal to 500 CSF. In some embodiments, the fibrillated fibers have an average of less than or equal to 650 CSF, less than or equal to 640 CSF, less than or equal to 630 CSF, less than or equal to 620 CSF, less than or equal to 610 CSF, less than or equal to 600 CSF, less than or equal to 575 CSF, less than or equal to 550 CSF, less than or equal to 525 CSF, less than or equal to 500 CSF, less than or equal to 450 CSF, less than or equal to 400 CSF, less than or equal to 350 CSF, less than or equal to 300 CSF, less than or equal to 250 CSF, less than or equal to 200 CSF, less than or equal to 150 CSF, or less than or equal to 100 CSF. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 20 CSF and less than or equal to 650 CSF or greater than or equal to 120 CSF and less than or equal to 500 CSF). Other ranges are also possible.

[0129] The Canadian Standard Freeness of the cellulose fibers may be measured according to a Canadian Standard Freeness test, specified by TAPPI test method T-227- OM-09 Freeness of pulp. The test can provide an average CSF value.

[0130] An unexpected feature of many of the abovementioned fibers (e.g., glass, synthetic, natural and / or fibrillated fibers) in the context of electrode media is that, in some embodiments, the above-mentioned fibers are electrically non-conductive. Typically, support structures for electrodes of lead acid battery are electrically conductive. For example, the lead grids typically used to support active material in lead acid battery electrodes are electrically conductive. Likewise, carbon fiber support structures may be electrically conductive. The use of electrically conductive support structures for electrodes can be beneficial, in some embodiments, since it can provide an electrically conductive pathway from the active material to an external circuit. However, it has been discovered within the context of this disclosure and recognized herein that the use of electrically non-conductive fiber webs (e.g., fiber webs consisting of electrically non-conductive fibers or comprising electrically non-conductive fibers in a weight percentage of greater than or equal to 70 wt%, greater than or equal to 80 wt%, greater than or equal to 90 wt%, greater than or equal to 95 wt%, or greater than or equal to 99 wt% versus the total weight of the fiber web) can provide other benefits when used in electrode media, as discussed elsewhere herein, resulting in lead acid battery electrodes that can outperform lead acid battery electrodes on conventional, electrically conductive support structures. Any of the above-mentioned fibers (e.g., glass, synthetic, natural and / or fibrillated fibers) may be electrically non-conductive with a minimum resistivity of greater than or equal to 102ohm-centimeters, greater than or equal to 103ohmcentimeters, greater than or equal to 104ohm-centimeters, greater than or equal to 105ohm-centimeters, greater than or equal to 106ohm-centimeters, greater than or equal to 107ohm-centimeters, greater than or equal to 108ohm-centimeters, or greater than or equal to 109ohm-centimeters.

[0131] Any of a variety of appropriate proportions of the fibers in the fiber web (e.g., the non-woven fiber web) may be electrically non-conductive. For example, glass fibers, multicomponent fibers, and / or fibrillated fibers may be electrically non-conductive. In some embodiments, a fiber web comprises electrically non-conductive fibers (e.g., a second plurality of fibers comprising electrically non-conductive fibers) in a number fraction of greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 25%, greater than or equal to 30%, greater than or equal to 35%, greater than or equal to 40%, greater than or equal to 45%, greater than or equal to 50%, greater than or equal to 55%, greater than or equal to 60%, greater than or equal to 65%, greater than or equal to 70%, greater than or equal to 75%, greater than or equal to 80%, greater than or equal to 85%, greater than or equal to 90%, or greater than or equal to 95% of the fibers of the fiber web. In some embodiments, a fiber web comprises electrically non-conductive fibers (e.g., a second plurality of fibers comprising electrically non-conductive fibers) in a number fraction of less than or equal to 100%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 75%, less than or equal to 70%, less than or equal to 65%, less than or equal to 60%, less than or equal to 55%, less than or equal to 50%, less than or equal to 45%, less than or equal to 40%, less than or equal to 35%, less than or equal to 30%, less than or equal to 25%, less than or equal to 20%, or less than or equal to 15% of the fibers of the fiber web, and / or greater than or equal to 10%. Combinations of these ranges are also possible (e.g., greater than or equal to 10% and less than or equal to 100%, greater than or equal to 50% and less than or equal to 100%, or greater than or equal to 90% and less than or equal to 100%). Other ranges are also possible.

[0132] The use of electrically conductive fibers may have certain mechanical disadvantages. For example, in some embodiments, electrically conductive fibers (e.g., carbon fibers) are mechanically elastic, making them difficult to process into fiber webs with high uniformity. However, depending on the embodiment, it may be advantageous to include at least some electrically conductive fibers in a fiber web described herein. Any of a variety of electrically conductive fiber materials may be used. For example, the electrically conductive fibers may be carbon fibers. In some embodiments, the fiber web comprises a plurality of glass fibers or silicon-based fibers that may be coated with a electrically conductive material such as a metal. For example, glass or silicon-based fibers may be coated with Pb.

[0133] A fiber web (e.g., a non-woven fiber web) described herein may comprise a plurality of electrically conductive fibers that makes up any of a variety of suitable amounts of the fiber web. For instance, in some embodiments a fiber web may comprise a second (or third, fourth, fifth, etc.) plurality of fibers that are non-glass fibers. In some embodiments, a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) makes up less than or equal to 90 wt%, less than or equal to 85 wt%, less than or equal to 80 wt%, less than or equal to 75 wt%, less than or equal to 70 wt%, less than or equal to 65 wt%, less than or equal to 60 wt%, less than or equal to 55 wt%, less than or equal to 50 wt%, less than or equal to 45 wt%, less than or equal to 40 wt%, less than or equal to 35 wt%, less than or equal to 30 wt%, less than or equal to 25 wt%, less than or equal to 20 wt%, less than or equal to 15 wt%, less than or equal to 10 wt%, or less than or equal to 5 wt% versus the weight of all fibers in a fiber web (or of the total weight of the fiber web). In some embodiments, a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) makes up greater than or equal to 0 wt%, greater than or equal to 5 wt%, greater than or equal to 10 wt%, greater than or equal to 15 wt%, greater than or equal to 20 wt%, greater than or equal to 25 wt%, greater than or equal to 30 wt%, greater than or equal to 35 wt%, greater than or equal to 40 wt%, greater than or equal to 45 wt%, greater than or equal to 50 wt%, greater than or equal to 55 wt%, greater than or equal to 60 wt%, greater than or equal to 65 wt%, greater than or equal to 70 wt%, greater than or equal to 75 wt%, greater than or equal to 80 wt%, or greater than or equal to 85 wt%, and / or less than or equal to 90 wt% of the weight of all fibers in a fiber web (or of the total weight of the fiber web). Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 90 wt%, greater than or equal to 0 wt% and less than or equal to 30 wt%, or greater than or equal to 0 wt% and less than or equal to 20 wt%). Other ranges are also possible.

[0134] Electrically conductive fibers described herein may have any of a variety of suitable average diameters. In some embodiments, a fiber web comprises a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) having an average diameter of greater than or equal to 1 micron, greater than or equal to 2 microns, greater than or equal to 4 microns, greater than or equal to 6 microns, greater than or equal to 8 microns, greater than or equal to 10 microns, greater than or equal to 12 microns, greater than or equal to 14 microns, greater than or equal to 16 microns, greater than or equal to 18 microns, greater than or equal to 20 microns, greater than or equal to 22 microns, greater than or equal to 24 microns, greater than or equal to 26 microns, or greater than or equal to 28 microns, and / or less than or equal to 30 microns. In some embodiments, a fiber web comprises a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) having an average diameter of less than or equal to 30 microns, less than or equal to 28 microns, less than or equal to 26 microns, less than or equal to 24 microns, less than or equal to 22 microns, less than or equal to 20 microns, less than or equal to 18 microns, less than or equal to 16 microns, less than or equal to 14 microns, less than or equal to 12 microns, less than or equal to 10 microns, less than or equal to 8 microns, less than or equal to 6 microns, less than or equal to 4 microns, or less than or equal to 2 microns, and / or greater than or equal to 1 micron. Combinations of these ranges are also possible (e.g., greater than or equal to 1 micron and less than or equal to 30 microns, greater than or equal to 10 microns and less than or equal to 20 microns, or greater than or equal to 12 microns and less than or equal to 16 microns). Other ranges are also possible.

[0135] The average diameter of a plurality of electrically conductive fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM).

[0136] Electrically conductive fibers described herein may have any of a variety of suitable average lengths. In some embodiments, a fiber web comprises a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) having an average length of greater than or equal to 1 mm, greater than or equal to 5 mm, greater than or equal to 10 mm, greater than or equal to 15 mm, greater than or equal to 20 mm, greater than or equal to 25 mm, greater than or equal to 30 mm, greater than or equal to 35 mm, greater than or equal to 40 mm, or greater than or equal to 45 mm, and / or less than or equal to 50 mm. In some embodiments, a fiber web comprises a plurality of electrically conductive fibers (e.g., a second plurality of fibers comprising electrically conductive fibers) having an average length of less than or equal to 50 mm, less than or equal to 45 mm, less than or equal to 40 mm, less than or equal to 35 mm, less than or equal to 30 mm, less than or equal to 25 mm, less than or equal to 20 mm, less than or equal to 15 mm, less than or equal to 10 mm, or less than or equal to 5 mm, and / or greater than or equal to 1 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 1 mm and less than or equal to 50 mm, greater than or equal to 5 mm and less than or equal to 20 mm, or greater than or equal to 10 mm and less than or equal to 15 mm). Other ranges are also possible.

[0137] The average length of a plurality of electrically conductive fibers may be measured using techniques known to those of skill in the art, e.g., scanning electron microscopy (SEM). A fiber web (e.g., a non-woven fiber web) may comprise a binder resin in any of a variety of suitable amounts. In some embodiments, a fiber web comprises a binder resin in an amount of greater than or equal to 0 wt%, greater than or equal to 2.5 wt%, greater than or equal to 5 wt%, greater than or equal to 7.5 wt%, greater than or equal to 10 wt%, greater than or equal to 12.5 wt%, greater than or equal to 15 wt%, or greater than or equal to 17.5 wt%. In some embodiments, a fiber web comprises a binder resin in an amount of less than or equal to 20 wt%, less than or equal to 17.5 wt%, less than or equal to 15 wt%, less than or equal to 12.5 wt%, less than or equal to 10 wt%, less than or equal to 7.5 wt%, less than or equal to 5 wt%, or less than or equal to 2.5 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 20 wt%, greater than or equal to 0 wt% and less than or equal to 10 wt%, or greater than or equal to 0 wt% and less than or equal to 5 wt%). Other ranges are also possible.

[0138] As discussed in greater detail below, in some embodiments binder resin is damaged or destroyed in at least a portion of a fiber web during formation of the fiber web into an electrode media. In some embodiments, a fiber web used in an electrode media described herein may have a non-uniform distribution of binder resin. For example, in some embodiments, a fiber web comprises binder resin but has an edge portion of the fiber web that does not include binder resin (e.g., since the binder resin at the edge portion may be burned off during lug formation on the edge portion of the fiber web, while at least some fibers of the edge portion, such as glass fibers, remain intact). In some embodiments, a fiber web described herein has a mass gradient of binder resin along at least a portion of a major surface of the fiber web. The lug formation process is described in greater detail below.

[0139] A fiber web described herein may have any of a variety of suitable porosities. According to some embodiments, a high fiber web porosity is advantageous. For example, a high fiber web porosity may be associated with increased room for paste impregnation, and / or with increased room for electrolyte penetration into the fiber web during use. In some embodiments, a fiber web has a porosity of greater than or equal to 70%, greater than or equal to 75%, greater than or equal to 80%, greater than or equal to 85%, greater than or equal to 90%, greater than or equal to 95%, greater than or equal to 97%, or greater than or equal to 98%. In some embodiments, a fiber web has a porosity of less than or equal to 99%, less than or equal to 98%, less than or equal to 97%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, or less than or equal to 75%. Combinations of these ranges are also possible (e.g., greater than or equal to 70% and less than or equal to 99%, greater than or equal to 85% and less than or equal to 98%, or greater than or equal to 90% and less than or equal to 97%). Other ranges are also possible.

[0140] The porosity of a fiber web is equivalent to 100% - [solidity of the fiber web]. The solidity of a fiber web is equivalent to the percentage of the interior of the fiber web occupied by solid material. The porosity and solidity determination described by this formula are appropriate for determining porosity of an unimpregnated fiber web. One non-limiting way of determining solidity of a fiber web is described in this paragraph, but other methods are also possible. The method described in this paragraph includes determining the basis weight and thickness of the fiber web and then applying the following formula: solidity = [basis weight of the fiber web / (density of the components forming the fiber web • thickness of the fiber web)] -100%. The density of the components forming the fiber web is equivalent to the average density of the material or material(s) forming the components of the fiber web (e.g., fibers, particles, resin), which is typically specified by the manufacturer of each material. The average density of the materials forming the components of the fiber web may be determined by: (1) determining the total volume of all of the components in the fiber web; and (2) dividing the total mass of all of the components in the fiber web by the total volume of all of the components in the fiber web. If the mass and density of each component of the fiber web are known, the volume of all the components in the fiber web may be determined by: (1) for each type of component, dividing the total mass of the component in the fiber web by the density of the component; and (2) summing the volumes of each component. If the mass and density of each component of the fiber web are not known, the volume of all the components in the fiber web may be determined in accordance with Archimedes’ principle.

[0141] A fiber web may have pores with any of a variety of suitable sizes. In some embodiments, large pore sizes may be advantageous for fiber webs used in electrode media. In some embodiments, a fiber web has a mean flow pore size of greater than or equal to 10 microns, greater than or equal to 20 microns, greater than or equal to 30 microns, greater than or equal to 40 microns, greater than or equal to 50 microns, greater than or equal to 60 microns, greater than or equal to 70 microns, greater than or equal to 80 microns, greater than or equal to 90 microns, greater than or equal to 100 microns, greater than or equal to 110 microns, greater than or equal to 120 microns, greater than or equal to 130 microns, or greater than or equal to 140 microns. In some embodiments, a fiber web has a mean flow pore size of less than or equal to 150 microns, less than or equal to 140 microns, less than or equal to 130 microns, less than or equal to 120 microns, less than or equal to 110 microns, less than or equal to 100 microns, less than or equal to 90 microns, less than or equal to 80 microns, less than or equal to 70 microns, less than or equal to 60 microns, less than or equal to 50 microns, less than or equal to 40 microns, less than or equal to 30 microns, or less than or equal to 20 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 10 microns and less than or equal to 150 microns, greater than or equal to 20 microns and less than or equal to 100 microns, or greater than or equal to 40 microns and less than or equal to 70 microns). Other ranges are also possible. The mean flow pore size of the unimpregnated fiber web may be determined according to ASTM F316 (2003).

[0142] In some embodiments, a fiber web has a maximum pore size of greater than or equal to 20 microns, greater than or equal to 30 microns, greater than or equal to 40 microns, greater than or equal to 50 microns, greater than or equal to 60 microns, greater than or equal to 70 microns, greater than or equal to 80 microns, greater than or equal to 90 microns, greater than or equal to 100 microns, greater than or equal to 110 microns, greater than or equal to 120 microns, greater than or equal to 130 microns, greater than or equal to 140 microns, greater than or equal to 150 microns, greater than or equal to 160 microns, greater than or equal to 170 microns, greater than or equal to 180 microns, greater than or equal to 190 microns, greater than or equal to 200 microns, greater than or equal to 210 microns, greater than or equal to 220 microns, greater than or equal to 230 microns, greater than or equal to 240 microns, greater than or equal to 250 microns, greater than or equal to 260 microns, greater than or equal to 270 microns, greater than or equal to 280 microns, or greater than or equal to 290 microns. In some embodiments, a fiber web has a maximum pore size of less than or equal to 300 microns, less than or equal to 290 microns, less than or equal to 280 microns, less than or equal to 270 microns, less than or equal to 260 microns, less than or equal to 250 microns, less than or equal to 240 microns, less than or equal to 230 microns, less than or equal to 220 microns, less than or equal to 210 microns, less than or equal to 200 microns, less than or equal to 190 microns, less than or equal to 180 microns, less than or equal to 170 microns, less than or equal to 160 microns, less than or equal to 150 microns, less than or equal to 140 microns, less than or equal to 130 microns, less than or equal to 120 microns, less than or equal to 110 microns, less than or equal to 100 microns, less than or equal to 90 microns, less than or equal to 80 microns, less than or equal to 70 microns, less than or equal to 60 microns, less than or equal to 50 microns, less than or equal to 40 microns, or less than or equal to 30 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 20 microns and less than or equal to 300 microns, greater than or equal to 50 microns and less than or equal to 200 microns, or greater than or equal to 80 microns and less than or equal to 150 microns). Other ranges are also possible.

[0143] The maximum pore size of the unimpregnated fiber web may be determined according to ASTM F316 (2003).

[0144] A fiber web (e.g., a non-woven fiber web) described herein may have any of a variety of suitable basis weights. In some embodiments, a fiber web has a basis weight of greater than or equal to 40 gsm, greater than or equal to 50 gsm, greater than or equal to 70 gsm, greater than or equal to 100 gsm, greater than or equal to 120 gsm, greater than or equal to 150 gsm, greater than or equal to 170 gsm, greater than or equal to 200 gsm, greater than or equal to 220 gsm, greater than or equal to 250 gsm, greater than or equal to 270 gsm, greater than or equal to 300 gsm, greater than or equal to 320 gsm, greater than or equal to 350 gsm, greater than or equal to 370 gsm, greater than or equal to 400 gsm, greater than or equal to 420 gsm, greater than or equal to 450 gsm, or greater than or equal to 470 gsm, and / or less than or equal to 500 gsm. In some embodiments, a fiber web has a basis weight of less than or equal to 500 gsm, less than or equal to 470 gsm, less than or equal to 450 gsm, less than or equal to 420 gsm, less than or equal to 400 gsm, less than or equal to 370 gsm, less than or equal to 350 gsm, less than or equal to 320 gsm, less than or equal to 300 gsm, less than or equal to 270 gsm, less than or equal to 250 gsm, less than or equal to 220 gsm, less than or equal to 200 gsm, less than or equal to 170 gsm, less than or equal to 150 gsm, less than or equal to 120 gsm, less than or equal to 100 gsm, less than or equal to 70 gsm, or less than or equal to 50 gsm, and / or greater than or equal to 40 gsm. Combinations of these ranges are also possible (e.g., greater than or equal to 40 gsm and less than or equal to 500 gsm, greater than or equal to 100 gsm and less than or equal to 400 gsm, or greater than or equal to 150 gsm and less than or equal to 300 gsm). Other ranges are also possible.

[0145] The basis weight of a fiber web may be determined according to the standard BCIS-03A Rev. Decl5

[0146] A fiber web (e.g., a non-woven fiber web) described herein may have any of a variety of suitable densities. Low fiber web densities may be advantageous, in some embodiments, at least inasmuch as that a low fiber web density may be associated with a high porosity, which can be advantageous as discussed above. In some embodiments, a fiber web has a density of less than or equal to 250 gsm / mm, less than or equal to 240 gsm / mm, less than or equal to 230 gsm / mm, less than or equal to 220 gsm / mm, less than or equal to 210 gsm / mm, less than or equal to 200 gsm / mm, less than or equal to 190 gsm / mm, less than or equal to 180 gsm / mm, less than or equal to 170 gsm / mm, less than or equal to 160 gsm / mm, less than or equal to 150 gsm / mm, less than or equal to 140 gsm / mm, less than or equal to 130 gsm / mm, less than or equal to 120 gsm / mm, less than or equal to 110 gsm / mm, less than or equal to 100 gsm / mm, less than or equal to 90 gsm / mm, less than or equal to 80 gsm / mm, less than or equal to 70 gsm / mm, or less than or equal to 60 gsm / mm, and / or greater than or equal to 50 gsm / mm. In some embodiments, a fiber web has a density of greater than or equal to 50 gsm / mm, greater than or equal to 60 gsm / mm, greater than or equal to 70 gsm / mm, greater than or equal to 80 gsm / mm, greater than or equal to 90 gsm / mm, greater than or equal to 100 gsm / mm, greater than or equal to 110 gsm / mm, greater than or equal to 120 gsm / mm, greater than or equal to 130 gsm / mm, greater than or equal to 140 gsm / mm, greater than or equal to 150 gsm / mm, greater than or equal to 160 gsm / mm, greater than or equal to 170 gsm / mm, greater than or equal to 180 gsm / mm, greater than or equal to 190 gsm / mm, greater than or equal to 200 gsm / mm, greater than or equal to 210 gsm / mm, greater than or equal to 220 gsm / mm, greater than or equal to 230 gsm / mm, or greater than or equal to 240 gsm / mm, and / or less than or equal to 250 gsm / mm. Combinations of these ranges are also possible (e.g., greater than or equal to 50 gsm / mm and less than or equal to 250 gsm / mm, greater than or equal to 80 gsm / mm and less than or equal to 200 gsm / mm, or greater than or equal to 100 gsm / mm and less than or equal to 140 gsm / mm). Other ranges are also possible.

[0147] The apparent density may be determined by dividing the basis weight by the thickness web thickness. Determining basis weight and web thickness is described elsewhere herein.

[0148] A fiber web (e.g., a non-woven fiber web) described herein may have any of a variety of suitable specific surface areas. In some embodiments, a fiber web has a specific surface area of greater than or equal to 0.1 m2 / g, greater than or equal to 0.3 m2 / g, greater than or equal to 0.5 m2 / g, greater than or equal to 0.7 m2 / g, greater than or equal to 1 m2 / g, greater than or equal to 1.2 m2 / g, greater than or equal to 1.4 m2 / g, greater than or equal to 1.6 m2 / g, greater than or equal to 1.8 m2 / g, greater than or equal to 2 m2 / g, greater than or equal to 2.2 m2 / g, greater than or equal to 2.4 m2 / g, greater than or equal to 2.7 m2 / g, greater than or equal to 2.9 m2 / g, greater than or equal to 3.1 m2 / g, greater than or equal to 3.3 m2 / g, greater than or equal to 3.5 m2 / g, greater than or equal to 3.7 m2 / g, greater than or equal to 3.9 m2 / g, greater than or equal to 4.1 m2 / g, greater than or equal to 4.4 m2 / g, greater than or equal to 4.6 m2 / g, or greater than or equal to 4.8 m2 / g. In some embodiments, a fiber web has a specific surface area of less than or equal to 5 m2 / g, less than or equal to 4.8 m2 / g, less than or equal to 4.6 m2 / g, less than or equal to 4.4 m2 / g, less than or equal to 4.1 m2 / g, less than or equal to 3.9 m2 / g, less than or equal to 3.7 m2 / g, less than or equal to 3.5 m2 / g, less than or equal to 3.3 m2 / g, less than or equal to 3.1 m2 / g, less than or equal to 2.9 m2 / g, less than or equal to 2.7 m2 / g, less than or equal to 2.4 m2 / g, less than or equal to 2.2 m2 / g, less than or equal to 2 m2 / g, less than or equal to 1.8 m2 / g, less than or equal to 1.6 m2 / g, less than or equal to 1.4 m2 / g, less than or equal to 1.2 m2 / g, less than or equal to 1 m2 / g, less than or equal to 0.7 m2 / g, less than or equal to 0.5 m2 / g, or less than or equal to 0.3 m2 / g. Combinations of these ranges are also possible (e.g., greater than or equal to 0.1 m2 / g and less than or equal to 5 m2 / g, greater than or equal to 0.3 m2 / g and less than or equal to 2 m2 / g, or greater than or equal to 0.5 m2 / g and less than or equal to 1 m2 / g). Other ranges are also possible.

[0149] The specific surface area may be determined in accordance with section 10 of Battery Council International Standard BCIS-03A (2009), "Recommended Battery Materials Specifications Valve Regulated Recombinant Batteries", section 10 being "Standard Test Method for Surface Area of Recombinant Battery Separator Mat". Following this technique, the specific surface area is measured via adsorption analysis using a BET surface analyzer (e.g., Micromeritics Gemini III 2375 Surface Area Analyzer) with nitrogen gas; the sample amount is between 0.5 and 0.6 grams in a 3 / 4" tube; and, the sample is allowed to degas at 100 °C for a minimum of 3 hours.

[0150] A fiber web (e.g., a non-woven fiber web) described herein may have any of a variety of suitable mechanical properties. According to some embodiments the use of fiber webs with high tensile strength is advantageous. For example, high tensile strengths may facilitate line-processing of the fiber web for paste impregnation and / or for lug impregnation of the fiber web. Additionally, a high mechanical strength may be associated with a higher damage resistance during repeated cycling of a battery comprising the non-woven fiber web. In some embodiments, a fiber web has a tensile strength of greater than or equal to 2 Ib / inch, greater than or equal to 3 Ib / inch, greater than or equal to 4 Ib / inch, greater than or equal to 5 Ib / inch, greater than or equal to 6 Ib / inch, greater than or equal to 7 Ib / inch, greater than or equal to 8 Ib / inch, greater than or equal to 9 Ib / inch, greater than or equal to 10 Ib / inch, greater than or equal to 11 Ib / inch, greater than or equal to 12 Ib / inch, greater than or equal to 13 Ib / inch, greater than or equal to 14 Ib / inch, greater than or equal to 15 Ib / inch, greater than or equal to 16 Ib / inch, greater than or equal to 17 Ib / inch, greater than or equal to 18 Ib / inch, or greater than or equal to 19 Ib / inch, and / or less than or equal to 20 Ib / inch in the machine direction. In some embodiments, a fiber web has a tensile strength of less than or equal to 20 Ib / inch, less than or equal to 19 Ib / inch, less than or equal to 18 Ib / inch, less than or equal to 17 Ib / inch, less than or equal to 16 Ib / inch, less than or equal to 15 Ib / inch, less than or equal to 14 Ib / inch, less than or equal to 13 Ib / inch, less than or equal to 12 Ib / inch, less than or equal to 11 Ib / inch, less than or equal to 10 Ib / inch, less than or equal to 9 Ib / inch, less than or equal to 8 Ib / inch, less than or equal to 7 Ib / inch, less than or equal to 6 Ib / inch, less than or equal to 5 Ib / inch, less than or equal to 4 Ib / inch, or less than or equal to 3 Ib / inch, and / or greater than or equal to 2 Ib / inch in the machine direction. Combinations of these ranges are also possible (e.g., greater than or equal to 2 Ib / inch and less than or equal to 20 Ib / inch, greater than or equal to 2 Ib / inch and less than or equal to 10 Ib / inch, or greater than or equal to 3 Ib / inch and less than or equal to 6 Ib / inch). Other ranges are also possible. The tensile strength of the unimpregnated fiber web in a direction (e.g., the machine direction, the cross direction) can be measured according to BCIS-03A Rev.

[0151] Decl5.

[0152] In some embodiments, a fiber web has a tensile strength of greater than or equal to 2 Ib / inch, greater than or equal to 3 Ib / inch, greater than or equal to 4 Ib / inch, greater than or equal to 5 Ib / inch, greater than or equal to 6 Ib / inch, greater than or equal to 7 Ib / inch, greater than or equal to 8 Ib / inch, greater than or equal to 9 Ib / inch, greater than or equal to 10 Ib / inch, greater than or equal to 11 Ib / inch, greater than or equal to 12 Ib / inch, greater than or equal to 13 Ib / inch, or greater than or equal to 14 Ib / inch, and / or less than or equal to 15 Ib / inch in the cross direction. In some embodiments, a fiber web has a tensile strength of less than or equal to 15 Ib / inch, less than or equal to 14 Ib / inch, less than or equal to 13 Ib / inch, less than or equal to 12 Ib / inch, less than or equal to 11 Ib / inch, less than or equal to 10 Ib / inch, less than or equal to 9 Ib / inch, less than or equal to 8 Ib / inch, less than or equal to 7 Ib / inch, less than or equal to 6 Ib / inch, less than or equal to 5 Ib / inch, less than or equal to 4 Ib / inch, or less than or equal to 3 Ib / inch, and / or greater than or equal to 2 Ib / inch in the cross direction. Combinations of these ranges are also possible (e.g., greater than or equal to 2 Ib / inch and less than or equal to 15 Ib / inch, greater than or equal to 2 Ib / inch and less than or equal to 7 Ib / inch, or greater than or equal to 2 Ib / inch and less than or equal to 4 Ib / inch). Other ranges are also possible.

[0153] According to some embodiments, the fiber web has a relatively high wet tensile strength, as well as a relatively high dry tensile strength. In some embodiments, a fiber web has a wet tensile strength of greater than or equal to 1 Ib / inch, greater than or equal to 1.5 Ib / inch, greater than or equal to 2 Ib / inch, greater than or equal to 2.5 Ib / inch, greater than or equal to 3 Ib / inch, greater than or equal to 3.5 Ib / inch, greater than or equal to 4 Ib / inch, greater than or equal to 4.5 Ib / inch, greater than or equal to 5 Ib / inch, greater than or equal to 5.5 Ib / inch, greater than or equal to 6 Ib / inch, greater than or equal to 6.5 Ib / inch, greater than or equal to 7 Ib / inch, greater than or equal to 7.5 Ib / inch, greater than or equal to 8 Ib / inch, greater than or equal to 8.5 Ib / inch, greater than or equal to 9 Ib / inch, or greater than or equal to 9.5 Ib / inch, and / or less than or equal to 10 Ib / inch in the machine direction. In some embodiments, a fiber web has a wet tensile strength of less than or equal to 10 Ib / inch, less than or equal to 9.5 Ib / inch, less than or equal to 9 Ib / inch, less than or equal to 8.5 Ib / inch, less than or equal to 8 Ib / inch, less than or equal to 7.5 Ib / inch, less than or equal to 7 Ib / inch, less than or equal to 6.5 Ib / inch, less than or equal to 6 Ib / inch, less than or equal to 5.5 Ib / inch, less than or equal to 5 Ib / inch, less than or equal to 4.5 Ib / inch, less than or equal to 4 Ib / inch, less than or equal to 3.5 Ib / inch, less than or equal to 3 Ib / inch, less than or equal to 2.5 Ib / inch, less than or equal to 2 Ib / inch, or less than or equal to 1.5 Ib / inch, and / or greater than or equal to 1 Ib / inch in the machine direction. Combinations of these ranges are also possible (e.g., greater than or equal to 1 Ib / inch and less than or equal to 10 Ib / inch, greater than or equal to 1 Ib / inch and less than or equal to 5 Ib / inch, or greater than or equal to 1.5 Ib / inch and less than or equal to 3 Ib / inch). Other ranges are also possible.

[0154] The wet tensile strength of the unimpregnated fiber web in a direction (e.g., the machine direction, the cross direction) can be measured by immersing the fiber web in deionized water for 1 minute, drip drying the fiber web for 30 seconds, and subsequently measuring the tensile strength of the fiber web according to BCIS-03A Rev. Decl5.

[0155] In some embodiments, a fiber web has a wet tensile strength of greater than or equal to 1 Ib / inch, greater than or equal to 1.5 Ib / inch, greater than or equal to 2 Ib / inch, greater than or equal to 2.5 Ib / inch, greater than or equal to 3 Ib / inch, greater than or equal to 3.5 Ib / inch, greater than or equal to 4 Ib / inch, greater than or equal to 4.5 Ib / inch, greater than or equal to 5 Ib / inch, greater than or equal to 5.5 Ib / inch, greater than or equal to 6 Ib / inch, greater than or equal to 6.5 Ib / inch, or greater than or equal to 7 Ib / inch, and / or less than or equal to 7.5 Ib / inch in the cross direction. In some embodiments, a fiber web has a wet tensile strength of less than or equal to 7.5 Ib / inch, less than or equal to 7 Ib / inch, less than or equal to 6.5 Ib / inch, less than or equal to 6 Ib / inch, less than or equal to 5.5 Ib / inch, less than or equal to 5 Ib / inch, less than or equal to 4.5 Ib / inch, less than or equal to 4 Ib / inch, less than or equal to 3.5 Ib / inch, less than or equal to 3 Ib / inch, less than or equal to 2.5 Ib / inch, less than or equal to 2 Ib / inch, or less than or equal to 1.5 Ib / inch, and / or greater than or equal to 1 Ib / inch in the cross direction. Combinations of these ranges are also possible (e.g., greater than or equal to 1 Ib / inch and less than or equal to 7.5 Ib / inch, greater than or equal to 1 Ib / inch and less than or equal to 3.5 Ib / inch, or greater than or equal to 1 Ib / inch and less than or equal to 2 Ib / inch). Other ranges are also possible.

[0156] High elongation at break may also be achieved for the fiber webs. High elongation at break may also be advantageous for fiber webs, because it is associated, according to some embodiments, with tougher, more resilient fiber webs that are less likely to tear during processing. Additionally, a high elongation at break may be associated with a higher damage resistance during repeated cycling of a battery comprising the non-woven fiber web. In some embodiments, a fiber web has an elongation at break of greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 3%, greater than or equal to 4%, greater than or equal to 5%, greater than or equal to 6%, greater than or equal to 7%, greater than or equal to 8%, greater than or equal to 9%, greater than or equal to 10%, greater than or equal to 11%, greater than or equal to 12%, greater than or equal to 13%, greater than or equal to 14%, greater than or equal to 15%, greater than or equal to 16%, greater than or equal to 17%, greater than or equal to 18%, or greater than or equal to 19%, and / or less than or equal to 20% in the machine direction. In some embodiments, a fiber web has an elongation at break of less than or equal to 20%, less than or equal to 19%, less than or equal to 18%, less than or equal to 17%, less than or equal to 16%, less than or equal to 15%, less than or equal to 14%, less than or equal to 13%, less than or equal to 12%, less than or equal to 11%, less than or equal to 10%, less than or equal to 9%, less than or equal to 8%, less than or equal to 7%, less than or equal to 6%, less than or equal to 5%, less than or equal to 4%, less than or equal to 3%, or less than or equal to 2%, and / or greater than or equal to 1% in the machine direction. Combinations of these ranges are also possible (e.g., greater than or equal to 1% and less than or equal to 20%, greater than or equal to 2% and less than or equal to 13%, or greater than or equal to 3% and less than or equal to 9%). Other ranges are also possible.

[0157] The elongation at break of the unimpregnated fiber web in a direction (e.g., the machine direction, the cross direction) can be measured according to BCIS-03A Rev. Decl5.

[0158] In some embodiments, a fiber web has an elongation at break of greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 4%, greater than or equal to 6%, greater than or equal to 8%, greater than or equal to 10%, greater than or equal to 12%, greater than or equal to 14%, greater than or equal to 16%, greater than or equal to 18%, greater than or equal to 20%, greater than or equal to 22%, greater than or equal to 24%, greater than or equal to 26%, or greater than or equal to 28%, and / or less than or equal to 30% in the cross-direction. In some embodiments, a fiber web has an elongation at break of less than or equal to 30%, less than or equal to 28%, less than or equal to 26%, less than or equal to 24%, less than or equal to 22%, less than or equal to 20%, less than or equal to 18%, less than or equal to 16%, less than or equal to 14%, less than or equal to 12%, less than or equal to 10%, less than or equal to 8%, less than or equal to 6%, less than or equal to 4%, or less than or equal to 2%, and / or greater than or equal to 1% in the cross direction. Combinations of these ranges are also possible (e.g., greater than or equal to 1% and less than or equal to 30%, greater than or equal to 2% and less than or equal to 20%, or greater than or equal to 4% and less than or equal to 10%). Other ranges are also possible.

[0159] Another mechanical advantage of the fiber webs provided herein is their plasticity, according to some embodiments. For example, it has been recognized herein that plastically deformable fiber webs can be homogenized using plastic deformation. For example, plastically deformable fiber webs may be flattened to a uniform thickness (e.g., using mechanical rollers).

[0160] In some embodiments, a fiber web has a plasticity of greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 25%, greater than or equal to 30%, greater than or equal to 35%, greater than or equal to 40%, greater than or equal to 45%, greater than or equal to 50%, or greater than or equal to 55%, and / or less than or equal to 60%. In some embodiments, a fiber web has a plasticity of less than or equal to 60%, less than or equal to 55%, less than or equal to 50%, less than or equal to 45%, less than or equal to 40%, less than or equal to 35%, less than or equal to 30%, less than or equal to 25%, less than or equal to 20%, less than or equal to 15%, or less than or equal to 10%, and / or greater than or equal to 5%. Combinations of these ranges are also possible (e.g., greater than or equal to 5% and less than or equal to 60%, greater than or equal to 15% and less than or equal to 45%, or greater than or equal to 20% and less than or equal to 40%). Other ranges are also possible.

[0161] The plasticity of the unimpregnated fiber web may be determined by the following protocol. A 10cm x 10cm sample may be compressed from 2kPa to lOOkPa and back to 2kPa in 3min, following a sinusoidal pressure profile. The plasticity is calculated as the by the expression (Tf-To) / To, where Tf is the final thickness (at 10 kPa, as described elsewhere herein) measured during the sinusoidal decompression from 100 kPa back to 2 kPa and To is the initial thickness (at 10 kPa) measured during the sinusoidal compression from 2 kPa to 100 kPa. Without wishing to be bound by any particular theory, a low plasticity may be associated with a highly elastic fiber web, since the high elasticity of the web allows it to recover most of its thickness.

[0162] An advantage of some fiber webs described herein is that, according to some embodiments, they are stable at elevated temperatures. Stability at elevated temperatures may be advantageous for a fiber web of an electrode media because it may allow the addition of an electrically conductive lug to the fiber web as discussed in greater detail below. Stability at elevated temperatures may be measured by measuring shrinkage of the fiber web at elevated temperatures. More stable fiber webs shrink less at elevated temperatures. The shrinkage of a fiber web at a particular temperature may be determined by the following procedure. First, the initial length of the fiber web in the relevant direction may be measured. Next, the fiber web may be placed in an oven set and equilibrated at the relevant temperature. The interior of the oven may contain air that is in fluid communication with ambient air external to the exterior of the oven. The humidity of the ambient air external to the oven may be 45%. The fiber web may be retained in this oven for 10 minutes and then removed and allowed to cool to room temperature in room temperature air. Then, a final length of the fiber web in the relevant direction may be measured. The shrinkage in the relevant direction can be determined by applying the following formula, using lengths taken in a consistent direction: shrinkage = [(initial length of the fiber web - final length of the fiber web) / initial length of the fiber web]. The relevant direction may be a major surface dimension such as a machine direction (MD) or a cross direction (CD). Shrinkage may also be measured in major surface directions other than the machine direction or cross direction. Shrinkage could also be measured in non-major surface dimensions (e.g., in a thickness dimension).

[0163] In some embodiments, a fiber web experiences a shrinkage of less than or equal to 25%, less than or equal to 24%, less than or equal to 23%, less than or equal to 22%, less than or equal to 21%, less than or equal to 20%, less than or equal to 19%, less than or equal to 18%, less than or equal to 17%, less than or equal to 16%, less than or equal to 15%, less than or equal to 14%, less than or equal to 13%, less than or equal to 12%, less than or equal to 11%, less than or equal to 10%, less than or equal to 9%, less than or equal to 8%, less than or equal to 7%, less than or equal to 6%, less than or equal to 5%, less than or equal to 4%, less than or equal to 3%, less than or equal to 2%, or less than or equal to 1% when retained in a 540 °C oven for 1 minute. In some embodiments, a fiber web experiences a shrinkage of greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 3%, greater than or equal to 4%, greater than or equal to 5%, greater than or equal to 6%, greater than or equal to 7%, greater than or equal to 8%, greater than or equal to 9%, greater than or equal to 10%, greater than or equal to 11%, greater than or equal to 12%, greater than or equal to 13%, greater than or equal to 14%, greater than or equal to 15%, greater than or equal to 16%, greater than or equal to 17%, greater than or equal to 18%, greater than or equal to 19%, greater than or equal to 20%, greater than or equal to 21%, greater than or equal to 22%, greater than or equal to 23%, or greater than or equal to 24%, and / or less than or equal to 25% when retained in a 540 °C oven for 1 minute. Combinations of these ranges are also possible (e.g., greater than or equal to 0% and less than or equal to 25%, greater than or equal to 1% and less than or equal to 15%, or greater than or equal to 2% and less than or equal to 7%). Other ranges are also possible.

[0164] In some embodiments, a fiber web has a shrinkage in the machine direction in one or more of the above-referenced ranges when retained in a 540 °C oven for 1 minutes. In some embodiments, a fiber web has a shrinkage in the cross direction in one or more of the above-referenced ranges when retained in a 540 °C oven for 1 minute.

[0165] In some embodiments, a fiber web experiences a shrinkage of less than or equal to 25%, less than or equal to 24%, less than or equal to 23%, less than or equal to 22%, less than or equal to 21%, less than or equal to 20%, less than or equal to 19%, less than or equal to 18%, less than or equal to 17%, less than or equal to 16%, less than or equal to 15%, less than or equal to 14%, less than or equal to 13%, less than or equal to 12%, less than or equal to 11%, less than or equal to 10%, less than or equal to 9%, less than or equal to 8%, less than or equal to 7%, less than or equal to 6%, less than or equal to 5%, less than or equal to 4%, less than or equal to 3%, less than or equal to 2%, or less than or equal to 1% when retained in a 650 °C oven for 2 hours. In some embodiments, a fiber web experiences a shrinkage of greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 3%, greater than or equal to 4%, greater than or equal to 5%, greater than or equal to 6%, greater than or equal to 7%, greater than or equal to 8%, greater than or equal to 9%, greater than or equal to 10%, greater than or equal to 11%, greater than or equal to 12%, greater than or equal to 13%, greater than or equal to 14%, greater than or equal to 15%, greater than or equal to 16%, greater than or equal to 17%, greater than or equal to 18%, greater than or equal to 19%, greater than or equal to 20%, greater than or equal to 21%, greater than or equal to 22%, greater than or equal to 23%, or greater than or equal to 24%, and / or less than or equal to 25% when retained in a 650 °C oven for 2 hours. Combinations of these ranges are also possible (e.g., greater than or equal to 0% and less than or equal to 25%, greater than or equal to 1% and less than or equal to 15%, or greater than or equal to 2% and less than or equal to 7%). Other ranges are also possible.

[0166] A fiber web may be resistant to degradation in sulfuric acid, depending on the embodiment. For example, in some embodiments, a fiber web is configured to be substantially free of metallic impurities extractable in sulfuric acid.

[0167] In some embodiments, a fiber web contains extractable Pb impurities in an amount of less than or equal to 20 ppm, less than or equal to 19 ppm, less than or equal to 18 ppm, less than or equal to 17 ppm, less than or equal to 16 ppm, less than or equal to 15 ppm, less than or equal to 14 ppm, less than or equal to 13 ppm, less than or equal to 12 ppm, less than or equal to 11 ppm, less than or equal to 10 ppm, less than or equal to 9 ppm, less than or equal to 8 ppm, less than or equal to 7 ppm, less than or equal to 6 ppm, less than or equal to 5 ppm, less than or equal to 4 ppm, less than or equal to 3 ppm, less than or equal to 2 ppm, or less than or equal to 1 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Pb impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 1 ppm, greater than or equal to 2 ppm, greater than or equal to 3 ppm, greater than or equal to 4 ppm, greater than or equal to 5 ppm, greater than or equal to 6 ppm, greater than or equal to 7 ppm, greater than or equal to 8 ppm, greater than or equal to 9 ppm, greater than or equal to 10 ppm, greater than or equal to 11 ppm, greater than or equal to 12 ppm, greater than or equal to 13 ppm, greater than or equal to 14 ppm, greater than or equal to 15 ppm, greater than or equal to 16 ppm, greater than or equal to 17 ppm, greater than or equal to 18 ppm, or greater than or equal to 19 ppm and / or less than or equal to 20 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 20 ppm, greater than or equal to 0 ppm and less than or equal to 6 ppm, or greater than or equal to 0 ppm and less than or equal to 5 ppm). Other ranges are also possible. The amount of extractable Pb impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0168] In some embodiments, a fiber web contains extractable Sr impurities in an amount of less than or equal to 20 ppm, less than or equal to 19 ppm, less than or equal to 18 ppm, less than or equal to 17 ppm, less than or equal to 16 ppm, less than or equal to 15 ppm, less than or equal to 14 ppm, less than or equal to 13 ppm, less than or equal to 12 ppm, less than or equal to 11 ppm, less than or equal to 10 ppm, less than or equal to 9 ppm, less than or equal to 8 ppm, less than or equal to 7 ppm, less than or equal to 6 ppm, less than or equal to 5 ppm, less than or equal to 4 ppm, less than or equal to 3 ppm, less than or equal to 2 ppm, or less than or equal to 1 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Sr impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 1 ppm, greater than or equal to 2 ppm, greater than or equal to 3 ppm, greater than or equal to 4 ppm, greater than or equal to 5 ppm, greater than or equal to 6 ppm, greater than or equal to 7 ppm, greater than or equal to 8 ppm, greater than or equal to 9 ppm, greater than or equal to 10 ppm, greater than or equal to 11 ppm, greater than or equal to 12 ppm, greater than or equal to 13 ppm, greater than or equal to 14 ppm, greater than or equal to 15 ppm, greater than or equal to 16 ppm, greater than or equal to 17 ppm, greater than or equal to 18 ppm, or greater than or equal to 19 ppm and / or less than or equal to 20 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 20 ppm, greater than or equal to 0 ppm and less than or equal to 6 ppm, or greater than or equal to 0 ppm and less than or equal to 3 ppm). Other ranges are also possible. The amount of extractable Sr impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0169] In some embodiments, a fiber web contains extractable Te impurities in an amount of less than or equal to 25 ppm, less than or equal to 24 ppm, less than or equal to 23 ppm, less than or equal to 22 ppm, less than or equal to 21 ppm, less than or equal to 20 ppm, less than or equal to 19 ppm, less than or equal to 18 ppm, less than or equal to 17 ppm, less than or equal to 16 ppm, less than or equal to 15 ppm, less than or equal to 14 ppm, less than or equal to 13 ppm, less than or equal to 12 ppm, less than or equal to 11 ppm, less than or equal to 10 ppm, less than or equal to 9 ppm, less than or equal to 8 ppm, less than or equal to 7 ppm, less than or equal to 6 ppm, less than or equal to 5 ppm, less than or equal to 4 ppm, less than or equal to 3 ppm, less than or equal to 2 ppm, or less than or equal to 1 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Te impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 1 ppm, greater than or equal to 2 ppm, greater than or equal to 3 ppm, greater than or equal to 4 ppm, greater than or equal to 5 ppm, greater than or equal to 6 ppm, greater than or equal to 7 ppm, greater than or equal to 8 ppm, greater than or equal to 9 ppm, greater than or equal to 10 ppm, greater than or equal to 11 ppm, greater than or equal to 12 ppm, greater than or equal to 13 ppm, greater than or equal to 14 ppm, greater than or equal to 15 ppm, greater than or equal to 16 ppm, greater than or equal to 17 ppm, greater than or equal to 18 ppm, greater than or equal to 19 ppm, greater than or equal to 20 ppm, greater than or equal to 21 ppm, greater than or equal to 22 ppm, greater than or equal to 23 ppm, or greater than or equal to 24 ppm and / or less than or equal to 25 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 25 ppm, greater than or equal to 0 ppm and less than or equal to 7 ppm, or greater than or equal to 0 ppm and less than or equal to 6 ppm). Other ranges are also possible. The amount of extractable Te impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0170] In some embodiments, a fiber web contains extractable Cr impurities in an amount of less than or equal to 40 ppm, less than or equal to 38 ppm, less than or equal to 36 ppm, less than or equal to 34 ppm, less than or equal to 32 ppm, less than or equal to 30 ppm, less than or equal to 28 ppm, less than or equal to 26 ppm, less than or equal to 24 ppm, less than or equal to 22 ppm, less than or equal to 20 ppm, less than or equal to 18 ppm, less than or equal to 16 ppm, less than or equal to 14 ppm, less than or equal to 12 ppm, less than or equal to 10 ppm, less than or equal to 8 ppm, less than or equal to 6 ppm, less than or equal to 4 ppm, or less than or equal to 2 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Cr impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 2 ppm, greater than or equal to 4 ppm, greater than or equal to 6 ppm, greater than or equal to 8 ppm, greater than or equal to 10 ppm, greater than or equal to 12 ppm, greater than or equal to 14 ppm, greater than or equal to 16 ppm, greater than or equal to 18 ppm, greater than or equal to 20 ppm, greater than or equal to 22 ppm, greater than or equal to 24 ppm, greater than or equal to 26 ppm, greater than or equal to 28 ppm, greater than or equal to 30 ppm, greater than or equal to 32 ppm, greater than or equal to 34 ppm, greater than or equal to 36 ppm, or greater than or equal to 38 ppm and / or less than or equal to 40 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 40 ppm, greater than or equal to 0 ppm and less than or equal to 16 ppm, or greater than or equal to 0 ppm and less than or equal to 10 ppm). Other ranges are also possible. The amount of extractable Cr impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0171] In some embodiments, a fiber web contains extractable Mn impurities in an amount of less than or equal to 20 ppm, less than or equal to 19 ppm, less than or equal to 18 ppm, less than or equal to 17 ppm, less than or equal to 16 ppm, less than or equal to 15 ppm, less than or equal to 14 ppm, less than or equal to 13 ppm, less than or equal to 12 ppm, less than or equal to 11 ppm, less than or equal to 10 ppm, less than or equal to 9 ppm, less than or equal to 8 ppm, less than or equal to 7 ppm, less than or equal to 6 ppm, less than or equal to 5 ppm, less than or equal to 4 ppm, less than or equal to 3 ppm, less than or equal to 2 ppm, or less than or equal to 1 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Mn impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 1 ppm, greater than or equal to 2 ppm, greater than or equal to 3 ppm, greater than or equal to 4 ppm, greater than or equal to 5 ppm, greater than or equal to 6 ppm, greater than or equal to 7 ppm, greater than or equal to 8 ppm, greater than or equal to 9 ppm, greater than or equal to 10 ppm, greater than or equal to 11 ppm, greater than or equal to 12 ppm, greater than or equal to 13 ppm, greater than or equal to 14 ppm, greater than or equal to 15 ppm, greater than or equal to 16 ppm, greater than or equal to 17 ppm, greater than or equal to 18 ppm, or greater than or equal to 19 ppm and / or less than or equal to 20 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 20 ppm, greater than or equal to 0 ppm and less than or equal to 6 ppm, or greater than or equal to 0 ppm and less than or equal to 4 ppm). Other ranges are also possible. The amount of extractable Mn impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0172] In some embodiments, a fiber web contains extractable Fe impurities in an amount of less than or equal to 350 ppm, less than or equal to 325 ppm, less than or equal to 300 ppm, less than or equal to 275 ppm, less than or equal to 250 ppm, less than or equal to 225 ppm, less than or equal to 200 ppm, less than or equal to 175 ppm, less than or equal to 150 ppm, less than or equal to 125 ppm, less than or equal to 100 ppm, less than or equal to 75 ppm, less than or equal to 50 ppm, or less than or equal to 25 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Fe impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 25 ppm, greater than or equal to 50 ppm, greater than or equal to 75 ppm, greater than or equal to 100 ppm, greater than or equal to 125 ppm, greater than or equal to 150 ppm, greater than or equal to 175 ppm, greater than or equal to 200 ppm, greater than or equal to 225 ppm, greater than or equal to 250 ppm, greater than or equal to 275 ppm, greater than or equal to 300 ppm, or greater than or equal to 325 ppm and / or less than or equal to 350 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 350 ppm, greater than or equal to 0 ppm and less than or equal to 100 ppm, greater than or equal to 0 ppm and less than or equal to 75 ppm, or greater than or equal to 0 ppm and less than or equal to 50 ppm). Other ranges are also possible. The amount of extractable Fe impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0173] In some embodiments, a fiber web contains extractable Co impurities in an amount of less than or equal to 40 ppm, less than or equal to 38 ppm, less than or equal to 36 ppm, less than or equal to 34 ppm, less than or equal to 32 ppm, less than or equal to 30 ppm, less than or equal to 28 ppm, less than or equal to 26 ppm, less than or equal to 24 ppm, less than or equal to 22 ppm, less than or equal to 20 ppm, less than or equal to 18 ppm, less than or equal to 16 ppm, less than or equal to 14 ppm, less than or equal to 12 ppm, less than or equal to 10 ppm, less than or equal to 8 ppm, less than or equal to 6 ppm, less than or equal to 4 ppm, or less than or equal to 2 ppm versus the weight of the dry fiber web and / or greater than or equal to 0 ppm. In some embodiments, a fiber web contains extractable Co impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 2 ppm, greater than or equal to 4 ppm, greater than or equal to 6 ppm, greater than or equal to 8 ppm, greater than or equal to 10 ppm, greater than or equal to 12 ppm, greater than or equal to 14 ppm, greater than or equal to 16 ppm, greater than or equal to 18 ppm, greater than or equal to 20 ppm, greater than or equal to 22 ppm, greater than or equal to 24 ppm, greater than or equal to 26 ppm, greater than or equal to 28 ppm, greater than or equal to 30 ppm, greater than or equal to 32 ppm, greater than or equal to 34 ppm, greater than or equal to 36 ppm, or greater than or equal to 38 ppm and / or less than or equal to 40 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 40 ppm, greater than or equal to 0 ppm and less than or equal to 16 ppm, or greater than or equal to 0 ppm and less than or equal to 2 ppm). Other ranges are also possible. The amount of extractable Co impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0174] In some embodiments, a fiber web contains extractable Ni impurities in an amount of less than or equal to 20 ppm, less than or equal to 19 ppm, less than or equal to 18 ppm, less than or equal to 17 ppm, less than or equal to 16 ppm, less than or equal to 15 ppm, less than or equal to 14 ppm, less than or equal to 13 ppm, less than or equal to 12 ppm, less than or equal to 11 ppm, less than or equal to 10 ppm, less than or equal to 9 ppm, less than or equal to 8 ppm, less than or equal to 7 ppm, less than or equal to 6 ppm, less than or equal to 5 ppm, less than or equal to 4 ppm, less than or equal to 3 ppm, less than or equal to 2 ppm, or less than or equal to 1 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Ni impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 1 ppm, greater than or equal to 2 ppm, greater than or equal to 3 ppm, greater than or equal to 4 ppm, greater than or equal to 5 ppm, greater than or equal to 6 ppm, greater than or equal to 7 ppm, greater than or equal to 8 ppm, greater than or equal to 9 ppm, greater than or equal to 10 ppm, greater than or equal to 11 ppm, greater than or equal to 12 ppm, greater than or equal to 13 ppm, greater than or equal to 14 ppm, greater than or equal to 15 ppm, greater than or equal to 16 ppm, greater than or equal to 17 ppm, greater than or equal to 18 ppm, or greater than or equal to 19 ppm and / or less than or equal to 20 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 20 ppm, greater than or equal to 0 ppm and less than or equal to 6 ppm, or greater than or equal to 0 ppm and less than or equal to 3 ppm). Other ranges are also possible. The amount of extractable Ni impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0175] In some embodiments, a fiber web contains extractable Cu impurities in an amount of less than or equal to 30 ppm, less than or equal to 28 ppm, less than or equal to 26 ppm, less than or equal to 24 ppm, less than or equal to 22 ppm, less than or equal to 20 ppm, less than or equal to 18 ppm, less than or equal to 16 ppm, less than or equal to 14 ppm, less than or equal to 12 ppm, less than or equal to 10 ppm, less than or equal to 8 ppm, less than or equal to 6 ppm, less than or equal to 4 ppm, or less than or equal to 2 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Cu impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 2 ppm, greater than or equal to 4 ppm, greater than or equal to 6 ppm, greater than or equal to 8 ppm, greater than or equal to 10 ppm, greater than or equal to 12 ppm, greater than or equal to 14 ppm, greater than or equal to 16 ppm, greater than or equal to 18 ppm, greater than or equal to 20 ppm, greater than or equal to 22 ppm, greater than or equal to 24 ppm, greater than or equal to 26 ppm, or greater than or equal to 28 ppm and / or less than or equal to 30 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 30 ppm, greater than or equal to 0 ppm and less than or equal to 10 ppm, or greater than or equal to 0 ppm and less than or equal to 2 ppm). Other ranges are also possible. The amount of extractable Cu impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0176] In some embodiments, a fiber web contains extractable Zn impurities in an amount of less than or equal to 250 ppm, less than or equal to 240 ppm, less than or equal to 230 ppm, less than or equal to 220 ppm, less than or equal to 210 ppm, less than or equal to 200 ppm, less than or equal to 190 ppm, less than or equal to 180 ppm, less than or equal to 170 ppm, less than or equal to 160 ppm, less than or equal to 150 ppm, less than or equal to 140 ppm, less than or equal to 130 ppm, less than or equal to 120 ppm, less than or equal to 110 ppm, less than or equal to 100 ppm, less than or equal to 90 ppm, less than or equal to 80 ppm, less than or equal to 70 ppm, less than or equal to 60 ppm, less than or equal to 50 ppm, less than or equal to 40 ppm, less than or equal to 30 ppm, less than or equal to 20 ppm, or less than or equal to 10 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Zn impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 10 ppm, greater than or equal to 20 ppm, greater than or equal to 30 ppm, greater than or equal to 40 ppm, greater than or equal to 50 ppm, greater than or equal to 60 ppm, greater than or equal to 70 ppm, greater than or equal to 80 ppm, greater than or equal to 90 ppm, greater than or equal to 100 ppm, greater than or equal to 110 ppm, greater than or equal to 120 ppm, greater than or equal to 130 ppm, greater than or equal to 140 ppm, greater than or equal to 150 ppm, greater than or equal to 160 ppm, greater than or equal to 170 ppm, greater than or equal to 180 ppm, greater than or equal to 190 ppm, greater than or equal to 200 ppm, greater than or equal to 210 ppm, greater than or equal to 220 ppm, greater than or equal to 230 ppm, or greater than or equal to 240 ppm and / or less than or equal to 250 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 250 ppm, greater than or equal to 0 ppm and less than or equal to 60 ppm, or greater than or equal to 0 ppm and less than or equal to 10 ppm). Other ranges are also possible. The amount of extractable Zn impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0177] In some embodiments, a fiber web contains extractable Ti impurities in an amount of less than or equal to 30 ppm, less than or equal to 28 ppm, less than or equal to 26 ppm, less than or equal to 24 ppm, less than or equal to 22 ppm, less than or equal to 20 ppm, less than or equal to 18 ppm, less than or equal to 16 ppm, less than or equal to 14 ppm, less than or equal to 12 ppm, less than or equal to 10 ppm, less than or equal to 8 ppm, less than or equal to 6 ppm, less than or equal to 4 ppm, or less than or equal to 2 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Ti impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 2 ppm, greater than or equal to 4 ppm, greater than or equal to 6 ppm, greater than or equal to 8 ppm, greater than or equal to 10 ppm, greater than or equal to 12 ppm, greater than or equal to 14 ppm, greater than or equal to 16 ppm, greater than or equal to 18 ppm, greater than or equal to 20 ppm, greater than or equal to 22 ppm, greater than or equal to 24 ppm, greater than or equal to 26 ppm, or greater than or equal to 28 ppm and / or less than or equal to 30 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 30 ppm, greater than or equal to 0 ppm and less than or equal to 10 ppm, or greater than or equal to 0 ppm and less than or equal to 6 ppm). Other ranges are also possible. The amount of extractable Ti impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0178] In some embodiments, a fiber web contains extractable Al impurities in an amount of less than or equal to 2500 ppm, less than or equal to 2400 ppm, less than or equal to 2300 ppm, less than or equal to 2200 ppm, less than or equal to 2100 ppm, less than or equal to 2000 ppm, less than or equal to 1900 ppm, less than or equal to 1800 ppm, less than or equal to 1700 ppm, less than or equal to 1600 ppm, less than or equal to 1500 ppm, less than or equal to 1400 ppm, less than or equal to 1300 ppm, less than or equal to 1200 ppm, less than or equal to 1100 ppm, less than or equal to 1000 ppm, less than or equal to 900 ppm, less than or equal to 800 ppm, less than or equal to 700 ppm, less than or equal to 600 ppm, less than or equal to 500 ppm, less than or equal to 400 ppm, less than or equal to 300 ppm, less than or equal to 200 ppm, or less than or equal to 100 ppm and / or greater than or equal to 0 ppm versus the weight of the dry fiber web. In some embodiments, a fiber web contains extractable Al impurities in an amount of greater than or equal to 0 ppm, greater than or equal to 100 ppm, greater than or equal to 200 ppm, greater than or equal to 300 ppm, greater than or equal to 400 ppm, greater than or equal to 500 ppm, greater than or equal to 600 ppm, greater than or equal to 700 ppm, greater than or equal to 800 ppm, greater than or equal to 900 ppm, greater than or equal to 1000 ppm, greater than or equal to 1100 ppm, greater than or equal to 1200 ppm, greater than or equal to 1300 ppm, greater than or equal to 1400 ppm, greater than or equal to 1500 ppm, greater than or equal to 1600 ppm, greater than or equal to 1700 ppm, greater than or equal to 1800 ppm, greater than or equal to 1900 ppm, greater than or equal to 2000 ppm, greater than or equal to 2100 ppm, greater than or equal to 2200 ppm, greater than or equal to 2300 ppm, or greater than or equal to 2400 ppm and / or less than or equal to 2500 ppm versus the weight of the dry fiber web. Combinations of these ranges are also possible (e.g., greater than or equal to 0 ppm and less than or equal to 2500 ppm, greater than or equal to 0 ppm and less than or equal to 600 ppm, or greater than or equal to 0 ppm and less than or equal to 400 ppm). Other ranges are also possible. The amount of extractable Al impurities may be determined in accordance with BCIS-03a Rev Dec 15.

[0179] In some embodiments, a fiber web has a shrinkage in the machine direction in one or more of the above-referenced ranges when retained in a 650 °C oven for 2 hours. In some embodiments, a fiber web has a shrinkage in the cross direction in one or more of the above-referenced ranges when retained in a 650 °C oven for 2 hours.

[0180] A fiber web as described above may be a layer. The term “layer” generally refers to an arrangement of material that, when the material is laid flat, has a thickness dimension, a depth dimension that is perpendicular to the thickness dimension, and a width dimension that is perpendicular to both the thickness dimension and the depth dimension, where the lengths of each of the depth dimension and the width dimension are at least 3 times the length of the thickness dimension. In some embodiments, the length of the depth dimension of the layer is at least 5 times, at least 10 times, at least 25 times, at least 50 times, at least 100 times, at least 500 times, or at least 1000 times the length of the thickness dimension of the layer. In some embodiments, the length of the width dimension of the layer is at least 5 times, at least 10 times, at least 25 times, at least 50 times, at least 100 times, at least 500 times, or at least 1000 times the length of the thickness dimension of the layer. The width and depth dimensions of a layer define its major surfaces.

[0181] A fiber web (e.g., a non-woven fiber web) described herein may have any of a variety of suitable thicknesses. In some embodiments, a fiber web has a thickness of greater than or equal to 0.25 mm, greater than or equal to 0.5 mm, greater than or equal to 0.7 mm, greater than or equal to 1 mm, greater than or equal to 1.2 mm, greater than or equal to 1.5 mm, greater than or equal to 1.7 mm, greater than or equal to 2 mm, greater than or equal to 2.2 mm, greater than or equal to 2.5 mm, greater than or equal to 2.7 mm, greater than or equal to 3 mm, greater than or equal to 3.2 mm, greater than or equal to 3.5 mm, greater than or equal to 3.7 mm, greater than or equal to 4 mm, greater than or equal to 4.2 mm, greater than or equal to 4.5 mm, greater than or equal to 4.7 mm, greater than or equal to 5 mm, greater than or equal to 6 mm, greater than or equal to 7 mm, greater than or equal to 8 mm, greater than or equal to 9 mm, greater than or equal to 10 mm, greater than or equal to 11 mm, greater than or equal to 12 mm, greater than or equal to 13 mm, or greater than or equal to 14 mm, and / or less than or equal to 15 mm. In some embodiments, a fiber web has a thickness of less than or equal to 15 mm, less than or equal to 14 mm, less than or equal to 13 mm, less than or equal to 12 mm, less than or equal to 11 mm, less than or equal to 10 mm, less than or equal to 9 mm, less than or equal to 8 mm, less than or equal to 7 mm, less than or equal to 6 mm, less than or equal to 5 mm, less than or equal to 4.7 mm, less than or equal to 4.5 mm, less than or equal to 4.2 mm, less than or equal to 4 mm, less than or equal to 3.7 mm, less than or equal to 3.5 mm, less than or equal to 3.2 mm, less than or equal to 3 mm, less than or equal to 2.7 mm, less than or equal to 2.5 mm, less than or equal to 2.2 mm, less than or equal to 2 mm, less than or equal to 1.7 mm, less than or equal to 1.5 mm, less than or equal to 1.2 mm, less than or equal to 1 mm, less than or equal to 0.7 mm, or less than or equal to 0.5 mm, and / or greater than or equal to 0.25 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 0.25 mm and less than or equal to 15 mm, greater than or equal to 1 mm and less than or equal to 4 mm, or greater than or equal to 1.5 mm and less than or equal to 3 mm). Other ranges are also possible. It should be understood that the above-mentioned ranges may describe an impregnated (e.g., with active material or lug material) or an unimpregnated fiber web, as the disclosure is not so limited.

[0182] The thickness of a fiber web described herein may be measured according to BCIS-03A, Rev Dec 2015, under 10 kPa of applied pressure.

[0183] A fiber web may have any of a variety of suitable length and width dimensions. For example, in some embodiments the fiber web may be the fiber web of an electrode media suitable for use in exactly one electrode of a battery. As another example, in some embodiments, the fiber web is a fiber web of a large electrode media suitable for use in a plurality of electrodes. For example, the fiber web may be part of a roll of electrode media that can be formed into multiple electrodes (e.g., by line-processing and subsequently cutting the electrode media).

[0184] A fiber web suitable for use in an electrochemical cell may have any of a variety of appropriate lengths and widths. In some embodiments, a fiber web suitable for use in an electrochemical cell has a length of greater than or equal to 10 mm, greater than or equal to 30 mm, greater than or equal to 50 mm, greater than or equal to 70 mm, greater than or equal to 90 mm, greater than or equal to 110 mm, greater than or equal to 130 mm, greater than or equal to 150 mm, greater than or equal to 170 mm, greater than or equal to 190 mm, greater than or equal to 210 mm, greater than or equal to 230 mm, greater than or equal to 250 mm, greater than or equal to 260 mm, greater than or equal to 280 mm, greater than or equal to 300 mm, greater than or equal to 320 mm, greater than or equal to 340 mm, greater than or equal to 360 mm, greater than or equal to 380 mm, greater than or equal to 400 mm, greater than or equal to 420 mm, greater than or equal to 440 mm, greater than or equal to 460 mm, or greater than or equal to 480 mm. In some embodiments, a fiber web suitable for use in an electrochemical cell has a length of less than or equal to 500 mm, less than or equal to 480 mm, less than or equal to 460 mm, less than or equal to 440 mm, less than or equal to 420 mm, less than or equal to 400 mm, less than or equal to 380 mm, less than or equal to 360 mm, less than or equal to 340 mm, less than or equal to 320 mm, less than or equal to 300 mm, less than or equal to 280 mm, less than or equal to 260 mm, less than or equal to 250 mm, less than or equal to 230 mm, less than or equal to 210 mm, less than or equal to 190 mm, less than or equal to 170 mm, less than or equal to 150 mm, less than or equal to 130 mm, less than or equal to 110 mm, less than or equal to 90 mm, less than or equal to 70 mm, less than or equal to 50 mm, or less than or equal to 30 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 10 mm and less than or equal to 500 mm, greater than or equal to 30 mm and less than or equal to 300 mm, or greater than or equal to 50 mm and less than or equal to 200 mm). Other ranges are also possible.

[0185] In some embodiments, a fiber web suitable for use in an electrochemical cell has a width of greater than or equal to 10 mm, greater than or equal to 30 mm, greater than or equal to 50 mm, greater than or equal to 70 mm, greater than or equal to 90 mm, greater than or equal to 110 mm, greater than or equal to 130 mm, greater than or equal to 150 mm, greater than or equal to 170 mm, greater than or equal to 190 mm, greater than or equal to 210 mm, greater than or equal to 230 mm, greater than or equal to 250 mm, greater than or equal to 260 mm, greater than or equal to 280 mm, greater than or equal to 300 mm, greater than or equal to 320 mm, greater than or equal to 340 mm, greater than or equal to 360 mm, greater than or equal to 380 mm, greater than or equal to 400 mm, greater than or equal to 420 mm, greater than or equal to 440 mm, greater than or equal to 460 mm, or greater than or equal to 480 mm. In some embodiments, a fiber web suitable for use in an electrochemical cell has a width of less than or equal to 500 mm, less than or equal to 480 mm, less than or equal to 460 mm, less than or equal to 440 mm, less than or equal to 420 mm, less than or equal to 400 mm, less than or equal to 380 mm, less than or equal to 360 mm, less than or equal to 340 mm, less than or equal to 320 mm, less than or equal to 300 mm, less than or equal to 280 mm, less than or equal to 260 mm, less than or equal to 250 mm, less than or equal to 230 mm, less than or equal to 210 mm, less than or equal to 190 mm, less than or equal to 170 mm, less than or equal to 150 mm, less than or equal to 130 mm, less than or equal to 110 mm, less than or equal to 90 mm, less than or equal to 70 mm, less than or equal to 50 mm, or less than or equal to 30 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 10 mm and less than or equal to 500 mm, greater than or equal to 30 mm and less than or equal to 300 mm, or greater than or equal to 50 mm and less than or equal to 200 mm). Other ranges are also possible.

[0186] A battery or electrochemical cell described herein may comprise a battery plate comprising an electrode media discussed above. The battery plate may generally include any of a variety of appropriate numbers of electrode media (e.g., 1, 2, or more electrode media). Generally, a battery plate is an article comprising an electrode (e.g., an electrode comprising the electrode media). In some embodiments, the battery plate includes an electrode comprising an electrode media and an active material. In some embodiments, the battery plate comprises an electrode comprising an electrode media and an active material, and further comprises one or more additional elements (e.g., a lug, an additional electrode). For example, in some embodiments, a battery plate includes more than one electrode. In a bipolar battery, for example, a battery plate may comprise both a positive electrode and a negative electrode (e.g., on opposite sides of the battery plate). The electrode may comprise (e.g., may be coextensive with) the entire electrode media, or may comprise only a portion of the electrode media of the battery plate. To provide an illustrative example, in a bipolar battery plate, an electrode may be coextensive with an entire electrode media. As another illustrative example, in some embodiments, a battery plate comprises a lug that is coextensive with a portion of the electrode media that is not comprised by the electrode.

[0187] A battery plate may comprise one or more layers. In some embodiments, a battery plate comprises exactly one layer (e.g., an electrode media). According to some embodiments, the battery plate comprises more than one layer. For example, in some embodiments, the battery plate has a bi-layered structure comprising an electrode media adjacent to a current collector electrically connected to the lug. The battery plate may include more than one electrode media. For example, the battery plate may comprise a first electrode comprising a first electrode media and a second electrode comprising a second electrode media (e.g., on opposite sides of a bipolar battery plate). Generally, the battery plate may include any of a variety of appropriate numbers of layers. For example, a battery plate may include 1, 2, 3, 4, 5, 6, 7, or 8 layers, in some embodiments.

[0188] In some embodiments, it may be advantageous for a battery plate to include a third layer, a fourth layer, and / or a fifth layer. For example, the battery plate may comprise a divider article (e.g., a divider layer) configured such that when the battery plate is installed in the battery, the divider article electrically connects the first electrode and the second electrode. The divider article may comprise one or more layers. In some embodiments, a divider article is configured such that when the battery plate is installed in a battery the divider article ionically isolates the first electrode and the second electrode. For example, the divider article may both electrically connect and ionically isolate the first electrode and the second electrode of a bipolar battery plate, in some embodiments. Any of a variety of suitable materials may be used for the divider article. For example, in some embodiments the divider article comprises a metal (e.g., the divider article may comprise a metal layer. In some embodiments, the divider article comprises a semiconductor (e.g., a degenerate semiconductor) such as silicon (e.g., the divider article may comprise a semiconductor layer). According to some embodiments, the divider article comprises a conductive polymer (e.g., the divider article may comprise a conductive polymer layer). The divider article may be a single layer (i.e., the divider article may be a divider layer) or may comprise a plurality of layers. Each layer of a divider article may independently comprise one or more of the forgoing materials (e.g., metals, semiconductors such as silicon, and / or conductive polymers).

[0189] A battery plate may comprise a lug, according to some embodiments. In other embodiments, an electrode media connected to (e.g., attached to) a lug is provided. Generally, a ‘lug’ is a connector that can be configured to electrically connect an active material of an electrode to an external circuit. A lug may be added to an electrode media, in some embodiments. For example, FIG. 1 presents a non-limiting schematic top- view illustration of an electrode media 101 comprising a fiber web 105 without a lug, according to some embodiments, while FIG. 2 presents a non-limiting, schematic illustration of a comparable electrode media 201 comprising a fiber web 205, to which a lug 211 has been added.

[0190] It is appreciated that a battery plate does not necessarily include a lug. For example, Valve-Regulated Lead Acid Batteries (VRLAs) , such as bipolar batteries, do not generally require electrodes comprising lugs, and may be prepared using electrode media without lugs. However, the use of a lug can provide certain advantages in electrochemical cells. For example, a lug may be configured to transmit electrical current between the electrochemical cell and an external circuit. In some embodiments, the lug supports the electrode media mechanically (e.g., by mechanically framing an edge of the electrode media, providing mechanical support to the electrode media). In some embodiments, a lug extends along (e.g., is attached to) one, two, three, four, or more sides of an electrode media. For example, a lug could extend along a circular edge of a circular electrode media (e.g., of the type that might be used in a cylindrical battery). FIG. 2 provides another example, where lug 211 extends along edge 202 of rectangular electrode media 201. In some embodiments, the use of battery plates comprising an electrode media with a lug extending along one edge of the electrode media (as shown in FIG. 2) is advantageous. For example, a battery plate comprising an electrode media with a lug extending along one edge of the electrode media may, in some embodiments, be prepared by an in-line process, making the battery plates easy to manufacture. The use of lugs in connection with the electrodes described herein may have additional advantages for backwards compatibility of the electrodes with other battery technologies. For example, in some embodiments, an electrode comprising a lug can be backwards- compatible with existing battery designs, making the lugged electrodes easier to incorporate into other batteries. For example, lug 211 of FIG. 2 comprises a tab 217 comparable to tabs of battery plates used in many conventional lead acid batteries. Lugs may be used alone, or may be used in combination with an additional current collector (e.g., a discrete layer configured to conduct current to the lug from the electrode), depending on the embodiment.

[0191] Of course, the omission of lugs may also be advantageous, in some circumstances. For example, where lugs are not necessary, batteries comprising battery plates without lugs may advantageously have a lower weight than batteries comprising lugged electrodes.

[0192] The lug may comprise any of a variety of appropriate lug materials. For example, the lug may comprise an electrically conductive lug material, such as a metal. In some embodiments, the lug material comprises (e.g., is) metallic lead in the form of pure lead or a lead alloy (e.g., a lead-calcium alloy, lead-tin alloy, or lead-aluminium alloy). According to some embodiments, the lug material comprises (e.g., is) a thermoplastic, thermoset, or reaction-set electrically conductive polymer. Suitable lug materials may be formable (e.g., by melt processing or solution processing).

[0193] A lug may have any of a variety of appropriate dimensions. For example, in some embodiments, a lug extends parallel to the length or width of the fiber web of an electrochemical cell over a distance within one of the length and / or width ranges provided above for the fiber web of an electrochemical cell.

[0194] An electrode media comprising a fiber web (e.g., an electrode media of a battery plate) may have a lug zone. A lug zone generally refers to a portion of a fiber web wherein lug material surrounds and / or penetrates the fibers of the fiber web (e.g., a portion of the fiber web that is coextensive with a portion of the lug). For example, referring again to FIG. 2, electrode media 201 comprises a lug zone 213, where lug 211 extends into electrode media 201 such that lug material surrounds and / or penetrates the fibers of fiber web 205 of electrode media 201. As shown, lug zone 213 represents a volume wherein the fiber web of electrode media 201 (and / or fiber web 205) is coextensive with the lug. A lug zone may provide a secure mechanical connection between the lug and the fiber web, and may provide electrical communication between the lug and the electrode.

[0195] Lug material may impregnate any of a variety of appropriate fractions of the (unimpregnated) pore volume of the lug zone. In some embodiments, lug material impregnates greater than or equal to 50%, greater than or equal to 55%, greater than or equal to 60%, greater than or equal to 65%, greater than or equal to 70%, greater than or equal to 75%, greater than or equal to 80%, greater than or equal to 85%, greater than or equal to 90%, greater than or equal to 95%, or greater than or equal to 98% of the pore volume of the lug zone. In some embodiments, lug material impregnates less than or equal to 100%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 75%, less than or equal to 70%, less than or equal to 65%, less than or equal to 60%, or less than or equal to 55% of the pore volume of the lug zone. Combinations of these ranges are also possible (e.g., greater than or equal to 50% and less than or equal to 100%, greater than or equal to 60% and less than or equal to 98%, or greater than or equal to 70% and less than or equal to 95%). Other ranges are also possible.

[0196] A battery plate comprising a lug may comprise an electrode that directly contacts the lug zone. For example, FIG. 3 shows a non-limiting, top-view schematic illustration of a battery plate 300 comprising a lug 311 attached to an electrode media 301. Battery plate 300 comprises an electrode 305 which comprises electrode media 301 comprising a fiber web 306 and an active material 307. Lug 311 is attached to electrode media 301 by a lug zone 313.

[0197] It should be understood that a lug may extend beyond a lug zone, such that a portion of the lug is not co-extensive with the fiber web. For example, referring again to FIG. 2, lug 211 extends beyond lug zone 213, since lug 211 comprises a portion 215 that is not coextensive with electrode media 201. The use of a lug that extends beyond the lug zone as shown in FIG. 2 may provide any of a number of advantages, including improved mechanical strength of the lug, better electrical conductivity of the lug, and / or better backward compatibility with other electrode technologies.

[0198] The lug may be formed by any of a variety of appropriate methods. At least some embodiments comprise forming a lug by melting a lug material and pressure impregnating it, while molten, into a fiber web. At least some embodiments comprise surrounding or enclosing a portion of the fiber web (e.g., an edge portion of the fiber web) in a die and impregnating (e.g., pressure impregnating) the molten lug material into the fiber web to form a lug zone. Impregnated, molten lug material may be allowed to cool and solidify. In at least some embodiments pressure impregnating the molten lug material into the fiber web includes pressure impregnating the molten lug material into the die. In other embodiments a lug material may be a thermoplastic, thermoset, or reaction-set electrically conductive polymer that is pressure impregnated into a fiber web. The die may comprise die parts that are brought together with the fiber web between. In some embodiments, a closing pressure or force of the die parts against the fiber web is less than a pressure impregnating the molten lug material into the die. In other embodiments pressure impregnating the molten lug material into the fiber web includes closing a die on the lug material and fiber web so that the die closing force pressure impregnates the molten lug material into the fiber web. According to some embodiments, closing the die parts holds the fiber web in place to allow the molten lug material to pressure impregnate the fiber web.

[0199] In some embodiments, a lug is formed via continuous pressure impregnation process as described herein and with reference to U.S. Patent Application No. US-2017- 0346068-A1, filed December 11, 2015, entitled “LEAD-ACID BATTERY ELECTRODE MANUFACTURE”, and patented as U.S. Patent No. 10,476,069, which is incorporated herein by reference in its entirety.

[0200] Briefly, a lug forming machine may be arranged to form a lug by pressure impregnation of the lug material into the fiber web as the fiber web moves relative to a pressure injection stage of a lug forming machine. A fiber web may move relative to the pressure injection stage on a heat sink conveyor of a lug forming machine. FIG. 4 provides a non-limiting, schematic illustration of a lug forming machine 400 according to some embodiments. Lug forming machine 400 comprises side by side pressure injectors 401 and 402 to form a continuous lug along opposite lengthwise edges of a fiber web 413. As illustrated, fiber web 413, can be provided to lug forming machine 400 as a continuous layer. In some embodiments, fiber web 413 can then be passed through lug forming machine 400 by being mounted above a conveyor 411 of lug forming machine 400. As illustrated, lug forming machine 400 may comprise a frame 403 supporting conveyer 411 and pressure injectors 401 and 402. According to some embodiments, conveyor 411 has a width across an axis of rotation equal to or greater than a width W of fiber web 413 so that conveyer 411 supports the full width of fiber web 413, as shown.

[0201] Lug forming machine 400 may comprise a fiber web feed system 415 configured to draw fiber web 413 through the lug forming machine. Fiber web feed system 415 is mounted on frame 403 in some embodiments. According to some embodiments, fiber web feed system 415 comprises drivers opposite nip rollers 421 located on the exit side of conveyor 411 in the machine direction.

[0202] During lug formation, fiber web 413 passes through a gap between conveyer 411 and pressure injectors 401 and 402 as pressure injection pulses from pressure injectors 401 and 402 impregnate fiber web 413 with molten lug material (e.g., molten Pb) along either edge of fiber web 413 to form a continuous lug.

[0203] The fiber webs discussed herein may be suitable for a lug-forming process that produces a lug zone. For example, the fiber webs may have a high thermal stability, as discussed in greater detail above. Likewise, high mechanical strength and plasticity may be advantageous for producing uniform and high-quality lug zones.

[0204] An electrochemical cell (e.g., of a battery) described herein may comprise an electrode comprising an electrode media and an active material. For example, electrode 305 of FIG. 3 comprises (a portion of) electrode media 301 and active material 307 distributed therein. An electrode may comprise an electrode media comprising a fiber web as discussed above. In some embodiments, the electrode is coextensive with the entire electrode media such that active material is distributed throughout the entire electrode media and / or fiber web. It should be understood that the present disclosure distinguishes the term “battery plate” from the term “electrode”. A bipolar battery plate, for example, may comprise two electrodes — a negative electrode associated with a first electrochemical cell and a positive electrode associated with a second electrochemical cell — as discussed herein.

[0205] An electrode may be a positive electrode comprising a positive active material (PAM). In some embodiments an electrode is a negative electrode comprising a negative active material (NAM). An electrode may span a portion of (e.g., the entirety of) a fiber web, as discussed above. In some embodiments, the electrode is part of a battery plate, comprising a lug, as discussed above. The fiber web may be flexible, and may help to accommodate volume changes of the active material during battery cycling. In some embodiments, the fibers reinforce the active material, e.g., helping to maintain the pore sizing and / or pore volumes.

[0206] The active material, and / or lug material, advantageously, contains no more than a low level of antimony, according to some embodiments. Without wishing to be bound by any particular theory, antimony present in the active material may promote undesirable side-reactions that result in hydrogen production and / or loss of water from the electrolyte. A dry active material or paste described herein may comprise antimony in an amount of less than or equal to 50 wt ppm, less than or equal to 48 wt ppm, less than or equal to 45 wt ppm, less than or equal to 42 wt ppm, less than or equal to 40 wt ppm, less than or equal to 38 wt ppm, less than or equal to 35 wt ppm, less than or equal to 32 wt ppm, less than or equal to 30 wt ppm, less than or equal to 28 wt ppm, less than or equal to 25 wt ppm, less than or equal to 22 wt ppm, less than or equal to 20 wt ppm, less than or equal to 18 wt ppm, less than or equal to 15 wt ppm, less than or equal to 12 wt ppm, less than or equal to 10 wt ppm, less than or equal to 8 wt ppm, less than or equal to 5 wt ppm, or less than or equal to 2 wt ppm. In some embodiments, a dry active material or paste described herein may comprise antimony in an amount of greater than or equal to 0 wt ppm, greater than or equal to 2 wt ppm, greater than or equal to 5 wt ppm, greater than or equal to 8 wt ppm, greater than or equal to 10 wt ppm, greater than or equal to 12 wt ppm, greater than or equal to 15 wt ppm, greater than or equal to 18 wt ppm, greater than or equal to 20 wt ppm, greater than or equal to 22 wt ppm, greater than or equal to 25 wt ppm, greater than or equal to 28 wt ppm, greater than or equal to 30 wt ppm, greater than or equal to 32 wt ppm, greater than or equal to 35 wt ppm, greater than or equal to 38 wt ppm, greater than or equal to 40 wt ppm, greater than or equal to 42 wt ppm, greater than or equal to 45 wt ppm, or greater than or equal to 48 wt ppm.

[0207] Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt ppm and less than or equal to 50 wt ppm, greater than or equal to 0 wt ppm and less than or equal to 20 wt ppm, or greater than or equal to 0 wt ppm and less than or equal to 10 wt ppm). Other ranges are also possible.

[0208] In some embodiments, the formed electrode (e.g., comprising an electrode media) comprises an expander. An expander may be in the paste or active material. In some embodiments, the expander is provided in in the electrolyte. According to some embodiments, an expander helps prevents agglomeration of sulphate particles at the negative plate. Without wishing to be bound by any particular theory, agglomeration of sulphate particles at the negative plate may form a solid mass of lead sulfate during discharge, thereby reducing battery performance. Any of a variety of suitable types of expander may be used. For example, the paste or active material may comprise a nonsynthetic organic expander such as an expander derived from a wood chemical, such as a lignin, a lignosulphonate, or a humic acid or salt thereof. In some embodiments, the paste or active material comprises a lignosulphonate expander. Non-limiting examples of a suitable lignosulphonate expander include those available from Borregaard A.S. Norway and sold under the Vanisperse™ name such as Vanisperse™ A, or Vanisperse™ HT-1, Vanisperse™ DCA, Maracell XE, Maracell B, Maracell E, and Maracell B. Other types of expander materials may comprise a functional organic additive (e.g., that may be in a liquid, solid, or gaseous form) having a molecular weight > 1 kDa. According to some embodiments, the paste or active material contains a doping agent (e.g., carbon such as carbon particles, carbon black, carbon fibers, graphite that may be fibers of various lengths, flakes, chunks or of other suitable configuration). In some embodiments, the paste or active material contains an organic polymer as an expander (e.g., synthetic organic polymers such as polycondensates of aromatic sulfones, including phenyl sulfone, naphthalene sulfone, benzyl sulfone, etc; polycondensates of aromatic disulfones, aromatic hydroxy-sulphones, aromatic dihydroxy-disulfones, etc; aromatic sulfonic acid polymers; naphthalene sulfonate condensate; a phenolic sulfonate condensate; a bisphenol condensate; and / or a combination, copolymer or salt thereof). Non-limiting examples of an organic polymer that may be used include Baypure CX - 100, Baypure DS, Polystyrenesulfonate, a napthlalene formaldehyde condensate or salt thereof, bisphenolA aminobenzenesulfonic acid, polyacrylate acid.

[0209] A paste or active material may comprise an expander in any of a variety of appropriate proportions at impregnation. In some embodiments, a paste or active material comprises an expander in an amount of greater than or equal to 0.00 wt%, greater than or equal to 0.01 wt%, greater than or equal to 0.05 wt%, greater than or equal to 0.10 wt%, greater than or equal to 0.15 wt%, greater than or equal to 0.20 wt%, greater than or equal to 0.25 wt%, greater than or equal to 0.30 wt%, greater than or equal to 0.35 wt%, greater than or equal to 0.40 wt%, greater than or equal to 0.45 wt%, greater than or equal to 0.50 wt%, greater than or equal to 0.60 wt%, greater than or equal to 0.70 wt%, greater than or equal to 0.80 wt%, greater than or equal to 0.90 wt%, greater than or equal to 1 wt%, greater than or equal to 1.2 wt%, greater than or equal to 1.5 wt%, greater than or equal to 1.8 wt%, greater than or equal to 2 wt%, greater than or equal to 2.5 wt%, greater than or equal to 3 wt%, greater than or equal to 3.5 wt%, greater than or equal to 4 wt%, greater than or equal to 4.5 wt%, greater than or equal to 5 wt%, greater than or equal to 5.5 wt%, greater than or equal to 6 wt%, greater than or equal to 6.5 wt%, greater than or equal to 7 wt%, greater than or equal to 7.5 wt%, greater than or equal to 8 wt%, greater than or equal to 8.5 wt%, greater than or equal to 9 wt%, greater than or equal to 9.5 wt%, or greater than or equal to 10 wt% at impregnation. In some embodiments, a paste or active material comprises an expander in an amount of less than or equal to 12 wt%, less than or equal to 10 wt%, less than or equal to 9.5 wt%, less than or equal to 9 wt%, less than or equal to 8.5 wt%, less than or equal to 8 wt%, less than or equal to 7.5 wt%, less than or equal to 7 wt%, less than or equal to 6.5 wt%, less than or equal to 6 wt%, less than or equal to 5.5 wt%, less than or equal to 5 wt%, less than or equal to 4.5 wt%, less than or equal to 4 wt%, less than or equal to 3.5 wt%, less than or equal to 3 wt%, less than or equal to 2.5 wt%, less than or equal to 2 wt%, less than or equal to 1.8 wt%, less than or equal to 1.5 wt%, less than or equal to 1.5 wt%, less than or equal to 1.2 wt%, less than or equal to 1 wt%, less than or equal to 0.90 wt%, less than or equal to 0.80 wt%, less than or equal to 0.70 wt%, less than or equal to 0.60 wt%, less than or equal to 0.50 wt%, less than or equal to 0.45 wt%, less than or equal to 0.40 wt%, less than or equal to 0.35 wt%, less than or equal to 0.30 wt%, less than or equal to 0.25 wt%, less than or equal to 0.20 wt%, less than or equal to 0.15 wt%, less than or equal to 0.10 wt%, or less than or equal to 0.05 wt% at impregnation. Combinations of these ranges are also possible (e.g., greater than or equal to 0.00 wt% and less than or equal to 12 wt%, greater than or equal to 0.01 wt% and less than or equal to 10 wt%, greater than or equal to 0.20 wt% and less than or equal to 5 wt%, or greater than or equal to 0.20 wt% and less than or equal to 0.40 wt%). Other ranges are also possible. According to some embodiments, the paste comprises more than one expander. It should, of course, be understood that if the paste comprises more than one expander, each individual expander may be included in an amount specified within one of the foregoing ranges.

[0210] An electrode for a lead acid battery may be formed by positioning an active material comprising lead and / or lead dioxide within an electrode media. For example, an active material may be positioned within an electrode media by a pasting process, wherein a paste comprising the active material is impregnated into at least a portion of the electrode media or fiber web to form an electrode. A formed electrode may then be assembled into an electrochemical cell or battery. After assembly, the battery may undergo a formation step, during which the battery becomes fully charged and ready for operation. Formation may involve passing an electric current through an assembly of alternating negative and positive electrodes separated an electrolyte and / or a separator. During formation, lead dioxide in a battery paste or active material disposed on a negative battery plate may be transformed into lead, and / or lead in a battery paste or active material disposed on the positive battery plate may be transformed into lead dioxide.

[0211] In some embodiments, an electrode is formed via a pasting process as described herein and with reference to International Application No. PCT / IB2016 / 057459, filed December 9, 2016, and entitled “LEAD- ACID BATTERY ELECTRODE MANUFACTURE”, which is incorporated herein by reference in its entirety.

[0212] Briefly, a lead acid battery paste or active material may comprise a mixture of Pb and PbO (e.g., in the form of particles of Pb and PbO). In some embodiments, a paste or active material comprises dilute sulfuric acid. According to some embodiments, a paste or active material comprises lead sulphate (PbSO4, e.g., in the form of particles). A paste or active material may optionally contain an additive. For example, the paste or active material may contain barium sulphate. Without wishing to be bound by any particular theory, in some embodiments, barium sulfate acts as a seed crystal for lead sulphate crystallisation, encouraging the lead to lead sulfate reaction.

[0213] A paste for a pasting process may comprise sulfuric acid in any of a variety of suitable amounts. In some embodiments, a paste comprises sulfuric acid in an amount of greater than or equal to 0 wt%, greater than or equal to 1 wt%, greater than or equal to 2 wt%, greater than or equal to 3 wt%, greater than or equal to 4 wt%, or greater than or equal to 5 wt%. In some embodiments, a paste comprises sulfuric acid in an amount of less than or equal to 6 wt%, less than or equal to 5 wt%, less than or equal to 4 wt%, less than or equal to 3 wt%, less than or equal to 2 wt%, or less than or equal to 1 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 6 wt%, greater than or equal to 1 wt% and less than or equal to 5 wt%, or greater than or equal to 2 wt% and less than or equal to 4 wt%). Other ranges are also possible.

[0214] Paste properties may be controlled to control the porosity and pore size of the final electrode, according to some embodiments. Suitable electrode porosity can provide a number of performance advantages, depending on the embodiment. For example, without wishing to be bound by any particular theory, porosity of the electrode may increase contact between the active material and the electrolyte, improving battery performance. A paste may have any of a variety of appropriate densities at impregnation. In some embodiments, a paste has a density at impregnation of greater than or equal to 1.5 g / cm3, greater than or equal to 1.8 g / cm3, greater than or equal to 2 g / cm3, greater than or equal to 2.2 g / cm3, greater than or equal to 2.5 g / cm3, greater than or equal to 2.8 g / cm3, greater than or equal to 3 g / cm3, greater than or equal to 3.2 g / cm3, greater than or equal to 3.5 g / cm3, greater than or equal to 3.8 g / cm3, greater than or equal to 4 g / cm3, greater than or equal to 4.2 g / cm3, greater than or equal to 4.5 g / cm3, greater than or equal to 4.8 g / cm3, greater than or equal to 5 g / cm3, greater than or equal to 5.2 g / cm3, greater than or equal to 5.5 g / cm3, greater than or equal to 5.8 g / cm3, greater than or equal to 6 g / cm3, greater than or equal to 6.2 g / cm3, greater than or equal to 6.5 g / cm3, or greater than or equal to 6.8 g / cm3. In some embodiments, a paste has a density at impregnation of less than or equal to 7 g / cm3, less than or equal to 6.8 g / cm3, less than or equal to 6.5 g / cm3, less than or equal to 6.2 g / cm3, less than or equal to 6 g / cm3, less than or equal to 5.8 g / cm3, less than or equal to 5.5 g / cm3, less than or equal to 5.2 g / cm3, less than or equal to 5 g / cm3, less than or equal to 4.8 g / cm3, less than or equal to 4.5 g / cm3, less than or equal to 4.2 g / cm3, less than or equal to 4 g / cm3, less than or equal to 3.8 g / cm3, less than or equal to 3.5 g / cm3, less than or equal to 3.2 g / cm3, less than or equal to 3 g / cm3, less than or equal to 2.8 g / cm3, less than or equal to 2.5 g / cm3, less than or equal to 2.2 g / cm3, less than or equal to 2 g / cm3, or less than or equal to 1.8 g / cm3. Combinations of these ranges are also possible (e.g., greater than or equal to 1.5 g / cm3and less than or equal to 7 g / cm3, greater than or equal to 3 g / cm3and less than or equal to 6.5 g / cm3, or greater than or equal to 3 g / cm3and less than or equal to 6 g / cm3). Other ranges are also possible.

[0215] In some embodiments the solid content (e.g., the active material content) of the paste and / or the liquid content (e.g., the sulfuric acid and / or solvent content) of the paste can be varied to achieve suitable paste densities. In some embodiments, a paste has a solid content of greater than 0 wt%, greater than or equal to 2 wt%, greater than or equal to 5 wt%, greater than or equal to 8 wt%, greater than or equal to 10 wt%, greater than or equal to 12 wt%, greater than or equal to 15 wt%, greater than or equal to 18 wt%, greater than or equal to 20 wt%, greater than or equal to 22 wt%, greater than or equal to 25 wt%, greater than or equal to 28 wt%, greater than or equal to 30 wt%, greater than or equal to 32 wt%, greater than or equal to 35 wt%, greater than or equal to 38 wt%, greater than or equal to 40 wt%, greater than or equal to 42 wt%, greater than or equal to 45 wt%, greater than or equal to 48 wt%, greater than or equal to 50 wt%, greater than or equal to 52 wt%, greater than or equal to 55 wt%, greater than or equal to 58 wt%, greater than or equal to 60 wt%, greater than or equal to 62 wt%, greater than or equal to 65 wt%, greater than or equal to 68 wt%, greater than or equal to 70 wt%, greater than or equal to 72 wt%, greater than or equal to 75 wt%, greater than or equal to 77 wt%, greater than or equal to 78 wt%, greater than or equal to 80 wt%, greater than or equal to 82 wt%, greater than or equal to 85 wt%, greater than or equal to 86 wt%, greater than or equal to 88 wt%, greater than or equal to 90 wt%, greater than or equal to 92 wt%, greater than or equal to 95 wt%, or greater than or equal to 96 wt%. In some embodiments, a paste has a solid content of less than or equal to 98 wt%, less than or equal to 96 wt%, less than or equal to 95 wt%, less than or equal to 92 wt%, less than or equal to 90 wt%, less than or equal to 88 wt%, less than or equal to 86 wt%, less than or equal to 85 wt%, less than or equal to 82 wt%, less than or equal to 80 wt%, less than or equal to 78 wt%, less than or equal to 77 wt%, less than or equal to 75 wt%, less than or equal to 72 wt%, less than or equal to 70 wt%, less than or equal to 68 wt%, less than or equal to 65 wt%, less than or equal to 62 wt%, less than or equal to 60 wt%, less than or equal to 58 wt%, less than or equal to 55 wt%, less than or equal to 52 wt%, less than or equal to 50 wt%, less than or equal to 48 wt%, less than or equal to 45 wt%, less than or equal to 42 wt%, less than or equal to 40 wt%, less than or equal to 38 wt%, less than or equal to 35 wt%, less than or equal to 32 wt%, less than or equal to 30 wt%, less than or equal to 28 wt%, less than or equal to 25 wt%, less than or equal to 22 wt%, less than or equal to 20 wt%, less than or equal to 18 wt%, less than or equal to 15 wt%, less than or equal to 12 wt%, less than or equal to 10 wt%, less than or equal to 8 wt%, less than or equal to 5 wt%, or less than or equal to 2 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 98 wt%, greater than or equal to 70 wt% and less than or equal to 88 wt%, or greater than or equal to 77 wt% and less than or equal to 86 wt%). Other ranges are also possible.

[0216] In some embodiments, a paste has a liquid content of greater than 0 wt%, greater than or equal to 1 wt%, greater than or equal to 2 wt%, greater than or equal to 3 wt%, greater than or equal to 4 wt%, greater than or equal to 5 wt%, greater than or equal to 6 wt%, greater than or equal to 7 wt%, greater than or equal to 8 wt%, greater than or equal to 9 wt%, greater than or equal to 10 wt%, greater than or equal to 11 wt%, greater than or equal to 12 wt%, greater than or equal to 13 wt%, greater than or equal to 14 wt%, greater than or equal to 15 wt%, greater than or equal to 17 wt%, greater than or equal to 20 wt%, greater than or equal to 22 wt%, greater than or equal to 25 wt%, or greater than or equal to 27 wt%. In some embodiments, a paste has a liquid content of less than or equal to 30 wt%, less than or equal to 27 wt%, less than or equal to 25 wt%, less than or equal to 22 wt%, less than or equal to 20 wt%, less than or equal to 17 wt%, less than or equal to 15 wt%, less than or equal to 14 wt%, less than or equal to 13 wt%, less than or equal to 12 wt%, less than or equal to 11 wt%, less than or equal to 10 wt%, less than or equal to 9 wt%, less than or equal to 8 wt%, less than or equal to 7 wt%, less than or equal to 6 wt%, less than or equal to 5 wt%, less than or equal to 4 wt%, less than or equal to 3 wt%, less than or equal to 2 wt%, or less than or equal to 1 wt%.

[0217] Combinations of these ranges are also possible (e.g., greater than 0 wt% and less than or equal to 30 wt% or greater than 0 wt% and less than or equal to 23 wt%). Other ranges are also possible.

[0218] A paste may have any of a variety of suitable shear strengths at impregnation. The paste may have a sufficiently low shear strength to flow (slump) when placed in a cylindrical shape on a horizontal surface under gravity. A sufficiently low shear strength for impregnation may be inferred, in some embodiments, when noticeable slumping is observed for a 30mm high by 30mm diameter cylinder of paste. Paste suitable for impregnation may have a creamy consistency. The consistency of the paste can be adjusted, in some embodiments, by adjusting the weight percentage of sulfuric acid in the paste. A paste may have any of a variety of suitable rheological properties at impregnation.

[0219] After mixing, the paste is applied to the electrode media, according to some embodiments. In some embodiments, pasting occurs using a pasting machine. In at least some embodiments pasting comprises applying the paste to the electrode media (e.g., fiber web) by impregnating the paste into the electrode media (e.g., fiber web) under pressure. In some embodiments, the paste is subjected to an ultrasound vibration during pasting.

[0220] Pressure applied during pasting may be provided in a confined pasting zone of a pasting machine. A pasting process may comprise moving at least a portion of an electrode media (e.g., fiber web) through the confined pasting zone to impregnate a paste through a major surface of the electrode media (e.g., fiber web) and into and through the electrode media. A confined pasting zone is operatively coupled to a pressure supply configured to maintain pressure on paste in the applied pasting zone, according to some embodiments. A confined pasting zone may be operatively coupled to a vibrator configured to vibrate the paste in the confined pasting zone. A pasting machine may be configured to move a electrode media continuously through a confined pasting zone as part of a continuous, in-line process for impregnating paste into the electrode media, where the electrode media is continuously moved through the machine, in further embodiments the electrode media can be under tension. In further embodiments the machine may be arranged to compress the electrode media as it moves into and / or through the confined pasting zone. This same confined pasting zone can further be provided without the use of a machine.

[0221] The paste may be applied such that any of a variety of suitable proportions of the pasted active material are impregnated into the fiber web (e.g., as opposed to remaining above a surface of the fiber web). In some embodiments, greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 25%, greater than or equal to 30%, greater than or equal to 35%, greater than or equal to 40%, greater than or equal to 45%, greater than or equal to 50%, greater than or equal to 55%, greater than or equal to 60%, greater than or equal to 65%, greater than or equal to 70%, or greater than or equal to 75%, and / or less than or equal to 100% of the paste (or resulting active material in the electrode) is impregnated into the fiber web. In some embodiments, less than or equal to 80%, less than or equal to 75%, less than or equal to 70%, less than or equal to 65%, less than or equal to 60%, less than or equal to 55%, less than or equal to 50%, less than or equal to 45%, less than or equal to 40%, less than or equal to 35%, less than or equal to 30%, less than or equal to 25%, less than or equal to 20%, less than or equal to 15%, or less than or equal to 10% of the paste (or resulting active material in the electrode) is impregnated into the fiber web. Combinations of the above-referenced ranges are possible. Other ranges are also possible.

[0222] FIG. 5 provides a non-limiting, schematic illustration of impregnation of a paste into an electrode media (e.g., fiber web), according to some embodiments. FIG. 5 shows an electrode media 504 (e.g., fiber web) moving in a machine direction indicated by arrow MD. Electrode media 504 is being drawn by driven rollers 512. During impregnation, electrode media 504 moves over a flat surface 501 such as a flat plate. A paste P is delivered onto electrode media 504 from a paste supply (not shown) opposite flat surface 501 via a paste delivery outlet 505 comprising an orifice 506. The orifice may be at least wide across the machine direction as the width of the electrode media. Immediately downstream of paste delivery outlet 505 in the machine direction is a vibrator 503, having a lower surface 508. Lower surface 508 extends across electrode media 504 and angles downwardly towards the electrode media in the machine direction as shown. It should, of course, be understood that in some embodiments lower surface 508 can be moved within a range of movement from the angled position to a position substantially co-planar with the electrode media. A confined pasting zone 502 is defined downstream of orifice 506, between lower surface 508 and flat surface 501. In some instances, a cross-sectional area of the confined pasting zone in the machine direction (illustrated as approximately triangular in FIG. 5), is wider upstream than downstream, as shown.

[0223] In use, as electrode media 504 moves forward in the machine direction, paste P is continuously delivered under pressure from orifice 506 into the confined pasting zone. The paste pressure may be a static pressure (e.g., a pumping pressure) on the wedge- shaped body of paste P maintained within the confined pasting zone. Without wishing to be bound by any particular theory, a pasting pressure may be chosen to overcome flow resistance of the fibers to the paste, frictional flow resistance of the fibers to the paste, and paste surface tension forces. Any of a variety of suitable pasting pressures may be used.

[0224] In some embodiments, a pasting pressure is greater than or equal to 0.2 kPa, greater than or equal to 0.5 kPa, greater than or equal to 1 kPa, greater than or equal to 5 kPa, greater than or equal to 10 kPa, greater than or equal to 15 kPa, greater than or equal to 20 kPa, greater than or equal to 25 kPa, greater than or equal to 30 kPa, greater than or equal to 35 kPa, greater than or equal to 40 kPa, greater than or equal to 45 kPa, greater than or equal to 50 kPa, greater than or equal to 55 kPa, greater than or equal to 60 kPa, greater than or equal to 65 kPa, greater than or equal to 70 kPa, greater than or equal to 75 kPa, greater than or equal to 80 kPa, greater than or equal to 85 kPa, greater than or equal to 90 kPa, or greater than or equal to 95 kPa. In some embodiments, a pasting pressure is less than or equal to 100 kPa, less than or equal to 95 kPa, less than or equal to 90 kPa, less than or equal to 85 kPa, less than or equal to 80 kPa, less than or equal to 75 kPa, less than or equal to 70 kPa, less than or equal to 65 kPa, less than or equal to 60 kPa, less than or equal to 55 kPa, less than or equal to 50 kPa, less than or equal to 45 kPa, less than or equal to 40 kPa, less than or equal to 35 kPa, less than or equal to 30 kPa, less than or equal to 25 kPa, less than or equal to 20 kPa, less than or equal to 15 kPa, less than or equal to 10 kPa, less than or equal to 5 kPa, less than or equal to 1 kPa, or less than or equal to 0.5 kPa. Combinations of these ranges are also possible (e.g., greater than or equal to 0.2 kPa and less than or equal to 100 kPa, greater than or equal to 0 kPa and less than or equal to 80 kPa, or greater than or equal to 0 kPa and less than or equal to 60 kPa). Other ranges are also possible.

[0225] The paste in the confined pasting zone may be considered as a body of flowing paste under pressure, according to some embodiments. In some embodiments, the paste is fluidized by vibration of vibrator 503.

[0226] In some embodiments, the porosity of an electrode comprising a fibrous material as an electrode media may be varied at least in part by controlling the method by which the fibrous material is impregnated with paste. For example, the degree of penetration of the paste into the electrode media and the resulting porosity of an electrode formed therefrom may be controlled by varying the pressure applied to the paste and / or vibration during impregnation.

[0227] After pasting, the electrodes are dried, for example by air drying or flash drying, and then cured.

[0228] An electrode may be air dried at any of a variety of suitable temperatures. In some embodiments, an electrode is air dried at a temperature of greater than or equal to 5 °C, greater than or equal to 10 °C, greater than or equal to 15 °C, greater than or equal to 20 °C, greater than or equal to 25 °C, greater than or equal to 30 °C, or greater than or equal to 35 °C. In some embodiments, an electrode is air dried at a temperature of less than or equal to 40 °C, less than or equal to 35 °C, less than or equal to 30 °C, less than or equal to 25 °C, less than or equal to 20 °C, less than or equal to 15 °C, or less than or equal to 10 °C. Combinations of these ranges are also possible (e.g., greater than or equal to 5 °C and less than or equal to 40 °C, or greater than or equal to 10 °C and less than or equal to 30 °C). Other ranges are also possible. An electrode may be air dried for any of a variety of suitable times. In some embodiments, an electrode is air dried for greater than or equal to 4 h, greater than or equal to 8 h, greater than or equal to 12 h, greater than or equal to 16 h, greater than or equal to 20 h, greater than or equal to 24 h, greater than or equal to 28 h, greater than or equal to 32 h, or greater than or equal to 36 h. In some embodiments, an electrode is air dried for less than or equal to 40 h, less than or equal to 36 h, less than or equal to 32 h, less than or equal to 28 h, less than or equal to 24 h, less than or equal to 20 h, less than or equal to 16 h, less than or equal to 12 h, or less than or equal to 8 h. Combinations of these ranges are also possible (e.g., greater than or equal to 4 h and less than or equal to 40 h, greater than or equal to 8 h and less than or equal to 36 h, or greater than or equal to 24 h and less than or equal to 36 h). Other ranges are also possible.

[0229] In some embodiments drying is by flash drying. Flash drying may comprise exposing an electrode to an elevated temperature for a short period of time. An electrode may be flash dried by heating the electrode to any of a variety of suitable temperatures. In some embodiments, an electrode is flash dried by heating the electrode to a temperature of greater than or equal to 40 °C, greater than or equal to 45 °C, greater than or equal to 50 °C, greater than or equal to 55 °C, greater than or equal to 60 °C, greater than or equal to 65 °C, greater than or equal to 70 °C, or greater than or equal to 75 °C. In some embodiments, an electrode is flash dried by heating the electrode to a temperature of less than or equal to 80 °C, less than or equal to 75 °C, less than or equal to 70 °C, less than or equal to 65 °C, less than or equal to 60 °C, less than or equal to 55 °C, less than or equal to 50 °C, or less than or equal to 45 °C. Combinations of these ranges are also possible (e.g., greater than or equal to 40 °C and less than or equal to 80 °C, or greater than or equal to 45 °C and less than or equal to 75 °C). Other ranges are also possible.

[0230] An electrode may be flash-dried at the elevated temperature for relatively short period of time. For example, in some embodiments, an electrode is flash dried at the elevated temperature for less than or equal to 60 s, less than or equal to 45 s, less than or equal to 30 s, or less than or equal to 15 s. In some embodiments, an electrode is flash dried at the elevated temperature for greater than or equal to 5 s, greater than or equal to 15 s, greater than or equal to 30 s, or greater than or equal to 45 s. Combinations of these ranges are also possible (e.g., greater than or equal to 5 s and less than or equal to 60 s, greater than or equal to 5 s and less than or equal to 45 s, or greater than or equal to 5 s and less than or equal to 30 s). Other ranges are also possible.

[0231] In at least some embodiments, the dried electrodes are dry to the touch and / or sufficiently dry to be capable of being stacked on top of one another without sticking together. After drying, an electrode may have any of a variety of suitable moisture contents. In some embodiments, a dried electrode has a moisture content of less than or equal to 15 wt%, less than or equal to 13 wt%, less than or equal to 12 wt%, less than or equal to 10 wt%, less than or equal to 8 wt%, less than or equal to 7 wt%, less than or equal to 5 wt%, or less than or equal to 4 wt%. In some embodiments, a dried electrode has a moisture content of greater than or equal to 2 wt%, greater than or equal to 4 wt%, greater than or equal to 5 wt%, greater than or equal to 7 wt%, greater than or equal to 8 wt%, greater than or equal to 10 wt%, greater than or equal to 12 wt%, or greater than or equal to 13 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 2 wt% and less than or equal to 15 wt%, greater than or equal to 3 wt% and less than or equal to 14 wt%, or greater than or equal to 5 wt% and less than or equal to 17 wt%). Other ranges are also possible.

[0232] Dried electrodes may be cured in an oven. In various embodiments, curing reduces the moisture content of the dried electrode. A cured electrode may have any of a variety of suitable moisture contents. In some embodiments, a cured electrode has a moisture content of less than or equal to 1 wt%, less than or equal to 0.9 wt%, less than or equal to 0.8 wt%, less than or equal to 0.7 wt%, less than or equal to 0.6 wt%, less than or equal to 0.5 wt%, less than or equal to 0.4 wt%, less than or equal to 0.3 wt%, less than or equal to 0.2 wt%, or less than or equal to 0.1 wt%. In some embodiments, a cured electrode has a moisture content of greater than or equal to 0 wt%, greater than or equal to 0.1 wt%, greater than or equal to 0.2 wt%, greater than or equal to 0.3 wt%, greater than or equal to 0.4 wt%, greater than or equal to 0.5 wt%, greater than or equal to 0.6 wt%, greater than or equal to 0.7 wt%, greater than or equal to 0.8 wt%, or greater than or equal to 0.9 wt%. Combinations of these ranges are also possible (e.g., greater than or equal to 0 wt% and less than or equal to 1 wt%, greater than or equal to 0 wt% and less than or equal to 0.9 wt%, or greater than or equal to 0 wt% and less than or equal to 0.8 wt%). Other ranges are also possible. A curing process may be performed by heating the electrode in an oven. An electrode may be cured at any of a variety of suitable temperatures. In some embodiments, an electrode is cured at a temperature of greater than or equal to 50 C, greater than or equal to 55 C, greater than or equal to 60 C, greater than or equal to 65 C, greater than or equal to 70 C, greater than or equal to 75 C, greater than or equal to 80 C, or greater than or equal to 85 C. In some embodiments, an electrode is cured at a temperature of less than or equal to 90 C, less than or equal to 85 C, less than or equal to 80 C, less than or equal to 75 C, less than or equal to 70 C, less than or equal to 65 C, less than or equal to 60 C, or less than or equal to 55 C. Combinations of these ranges are also possible (e.g., greater than or equal to 50 C and less than or equal to 90 C, or greater than or equal to 55 C and less than or equal to 85 C). Other ranges are also possible.

[0233] The electrode may be cured by any of a variety of suitable protocols. To provide one, non-limiting example, in some embodiments, an oven containing the electrode is slowly heated to one of the above-mentioned temperatures. In some embodiments, the relative humidity of the oven is relatively high while the electrode is heated. For example, the initial relative humidity of the oven can be greater than or equal to 80%, greater than or equal to 90%, or greater than or equal to 95%, in some embodiments. The relative humidity of the oven may be slowly reduced while maintaining the temperature of the oven in order to cure the electrode. The relative humidity of the oven may be decreased to a relative humidity of less than or equal to 20%, less than or equal to 10%, or less than or equal to 5% during curing. The oven may then be maintained at the low relative humidity and elevated temperature for a period of time, before progressively reducing said temperature to room temperature while increasing the relative humidity to about, for example 20%. It should, of course, be understood that other curing processes are also possible as the disclosure is not so limited.

[0234] Electrode media, electrodes, and / or battery plates as described herein may be used in any of a variety of suitable batteries. Generally, a battery comprises one or more electrochemical cells, each electrochemical cell including a first electrochemical cell and a second electrochemical cell. In each electrochemical cell, electrons may pass from a first battery plate (e.g., comprising a negative electrode) to a second battery plate (e.g., comprising a positive electrode) during discharge and from the second battery plate to the first battery plate during charge. Positively charged ions may also flow through the electrochemical cell during each of these processes in a direction opposite to a direction of electron flow. An electrochemical cell may further comprise an electrolyte configured to transport these ions and / or a separator disposed between electrodes of opposing polarity. The electrochemical cell may comprise one or more battery plates. In some embodiments, the electrochemical cell comprises the whole battery plate. According to some embodiments, the electrochemical cell comprises a portion of a battery plate. For example, a first electrochemical cell may comprise a first electrode of a battery plate and a second electrochemical cell may comprise a second electrode of the battery plate as discussed above, according to some embodiments.

[0235] The batteries described herein may comprise a plurality of electrochemical cells. For example, in some embodiments, a battery comprises greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, greater than or equal to 5, greater than or equal to 10, greater than or equal to 15, greater than or equal to 20, greater than or equal to 30, or greater than or equal to 50 electrochemical cells. In some embodiments, a battery comprises less than or equal to 250, less than or equal to 225, less than or equal to 200, less than or equal to 175, less than or equal to 150, less than or equal to 125, less than or equal to 100, less than or equal to 75, less than or equal to 50, or less than or equal to 25 electrochemical cells. Combinations of these ranges are also possible (e.g., greater than or equal to 2 and less than or equal to 250, greater than or equal to 3 and less than or equal to 100, or greater than or equal to 5 and less than or equal to 10 electrochemical cells). Other ranges are also possible. In some embodiments, a battery comprises exactly 1 electrochemical cell.

[0236] A battery may be a bipolar battery, in some embodiments. Bipolar batteries comprise a battery plate that comprises a positive electrode of a first electrochemical cell and a negative electrode of a second electrochemical cell. A battery plate of a bipolar battery may comprise exactly one electrode media (e.g., supporting both a positive and a negative electrode) or may comprise a plurality of electrode media (e.g., including a first electrode media supporting a first electrode of a first electrochemical cell and a second electrode media supporting a second electrode of a second electrochemical cell). In contrast to battery plates of a bipolar battery, any battery plate of a monopolar battery serves exclusively as a negative electrode or as a positive electrode of an electrochemical cell.

[0237] FIG. 6 provides a schematic cross-section of a non-limiting battery 600, according to some embodiments. Battery 600 is presented as a bipolar battery that comprises a stack 625 of electrochemical cells 601, 602, and 603 enclosed by a housing 650. A first bipolar battery plate 605 is disposed between electrochemical cells 601 and 602 and a second bipolar battery plate 605 is disposed between electrochemical cells 602 and 603. Each bipolar battery plate 605 comprises a positive electrode 607 comprising an electrode media and a negative electrode 609 comprising an electrode media, although it should of course be understood that other electrode configurations of the bipolar battery plate are possible as the disclosure is not so limited. Between the positive electrodes 607 and negative electrodes 609 of each battery plate are divider layers (e.g., metal foil) 611 that electrically connects and ionically isolates positive electrode 607 and negative electrode 609 of each bipolar battery plate 605.

[0238] A battery plate of a bipolar battery does not require a lug. In some embodiments, a battery plate of a bipolar battery is permeable to electron flow through major surfaces faces of the battery plate, but are impermeable to electrolyte.

[0239] A negative electrode comprising a negative active material (NAM) and a positive electrode comprising a positive active material (PAM) may be provided on opposing surfaces of an electrode media of a bipolar battery plate. A bipolar battery may comprise one bipolar plate, but often comprises a stack of bipolar plates. In some embodiments, a number of bipolar battery plates of a bipolar battery is one less than the number of electrochemical cells of the bipolar battery (e.g., such that the bipolar battery plates may be disposed between consecutive pairs of electrochemical cells of a stack of electrochemical cells of the battery). A bipolar battery may further comprise a positive end comprising a positive electrode and negative end comprising a negative electrode located at opposite ends of the bipolar plate or stack of bipolar plates, facing electrodes of opposite polarity with separators in between, according to some embodiments. For example, referring again to FIG. 6, battery 600 comprises an end battery plate 615 comprising a positive electrode 617 and an end battery plate 635 comprising a negative electrode 639, located at opposite ends of stack 625 of electrochemical cells 601, 602, and 603. Each of battery plates 615 and 635 is shown comprises a current collector 621, but it should of course be understood that one or both of the endplates could comprise a lug in addition to or instead of current collectors 621, as the disclosure is not so limited. As shown, each of electrochemical cells 601, 602, and 603 includes a separator 619 disposed between a positive electrode and a negative electrode.

[0240] A battery or electrochemical cell described herein may be used in any of a variety of suitable applications. For example, in some embodiments, a battery or electrochemical cell described herein is used in a vehicle. The battery may be used in any of a variety of suitable types of vehicle. For example, the battery may be used in a road vehicle (e.g., a car, a truck, a motorcycle, a scooter), a watercraft (e.g., a boat), or an aircraft (e.g., an autonomous aircraft such as a drone). In some embodiments, a battery is used in an energy storage application, e.g., for an energy storage system (ESS). The Energy storage systems may used for residential and / or commercial energy storage applications.

[0241] To assemble a battery, in some embodiments, electrodes are inserted into an electrochemical cell container, and electrically connected as a stack of alternating positive and negative electrodes with a suitable electrolyte and / or separator between each positive and negative electrode. A stack may then be assembled and provided and / or inserted into a battery casing. A stack may be compressed (e.g., to ensure the electrodes and separators are compressed against one another). A lid may be placed on the casing or the casing otherwise sealed. In some embodiments, electrolyte is added to the lidded or sealed casing. In some embodiments, a vacuum is drawn in the casing (e.g., to aid electrolyte addition. In some embodiments, electrolyte addition can be carried out several times (interspersed with electrolyte removal) to ensure full saturation of the separator with the electrolyte.

[0242] After assembly, the battery or electrochemical cell is then subjected to an initial charge for electrochemical cell formation, according to some embodiments. During initial electrode or electrochemical cell formation (the first charge cycle during which active particle linkages form, as discussed above) electrode or electrochemical cell formation may occur, without wishing to be bound by any particular theory, by formation of an electrically conductive framework. Formation may also generate small PbSO4 particles. In some embodiments, the small PbSCU particles attach to the electrically conductive framework to provide and receive current. It may be advantageous that during formation, charging current is pulsed (e.g., is pulsed periodically). However, non-pulsed charging is also possible, as the disclosure is not so limited.

[0243] To provide a specific, non-limiting example of battery assembly, assembly of 12V VRLA AGM batteries is discussed below. 12V VRLA AGM batteries generally follow a standard construction process where a 2V electrochemical cell or plate group is constructed using the electrodes in an alternative configuration of 1 negative, 1 positive with a separator in between. The plate groups are then stacked together, to form a stack which can then undergo compression to ensure each stack fits into the chambers of the battery casing and to ensure contact between the electrodes themselves and the separator. In some cases, a plunger moves across the top of the plate group to force the battery stack into each of the chambers. Each chamber with a stack or plate group forms an electrochemical cell. A cast on strap is applied to connect each electrochemical cell to the terminals of the batteries. A lid is placed securely on the battery casing. Electrolyte filling then commences, where a vacuum is drawn on the battery and at the same time the electrolyte is introduced into the battery. The vacuum forces electrolyte into the separator and plates. This process may be repeated several times to ensure full saturation. The battery is then ready to undergo formation. This 12V VRLA AGM assembly process can be used for batteries of other architectures. For example, the 12V VRLA AGM assembly process may be used to prepare a 48V battery.

[0244] An electrochemical cell or battery described herein may have any of a variety of suitable performance properties. For example, a battery or electrochemical cell may be configured to have suitable: formation properties; discharge properties such as C20 discharge properties, reserve capacity discharge properties, and Cold Cranking Amps (CCA) discharge properties; water consumption; and / or cycle life.

[0245] A battery or electrochemical cell may have any of a variety of suitable water consumptions. One advantage of using the electrode media described herein is that, in some embodiments, the electrode media may be associated with relatively low water consumption by the battery or electrochemical cell. In some embodiments the water consumption of the battery is less than or equal to 9 g / (Ah C20), less than or equal to 8 g / (Ah C20), less than or equal to 7 g / (Ah C20), less than or equal to 6 g / (Ah C20), less than or equal to 5 g / (Ah C20), less than or equal to 4 g / (Ah C20), less than or equal to 3 g / (Ah C20), less than or equal to 2 g / (Ah C20), or less than or equal to 1 g / (Ah C20). In some embodiments the water consumption of the battery is greater than or equal to 0 g / (Ah C20), greater than or equal to 1 g / (Ah C20), greater than or equal to 2 g / (Ah C20), greater than or equal to 3 g / (Ah C20), greater than or equal to 4 g / (Ah C20), greater than or equal to 5 g / (Ah C20), greater than or equal to 6 g / (Ah C20), greater than or equal to 7 g / (Ah C20), or greater than or equal to 8 g / (Ah C20). Combinations of these ranges are also possible (e.g., greater than or equal to 0 g / (Ah C20) and less than or equal to 9 g / (Ah C20), greater than or equal to 0 g / (Ah C20) and less than or equal to 8 g / (Ah C20), or greater than or equal to 1 g / (Ah C20) and less than or equal to 7 g / (Ah C20)). Other ranges are also possible. Water consumption is as measured in accordance to the European Standard (EN50432-l:2015), as set out in Table 1 below:

[0246] Table 1

[0247] The following examples are intended to illustrate certain embodiments of the present disclosure, but do not exemplify the full scope of the disclosure.

[0248] EXAMPLE 1

[0249] This example sets out processability tests of fiber webs having different weight percentages of glass fiber types, according to some embodiments.

[0250] Samples of fiber webs were fabricated using various weight percentages of different types of glass fibers obtained from manufacturers. These glass fibers were processed in a paper machine to create non-woven fiber webs. The processability of each sample was assessed, and each sample was determined to have a “high” or “low” processing difficulty, as shown in Table 2. Additional observations were made about the characteristics of the fiber web samples after processing, which are also noted in Table 2. Table 2 - Processability of samples in paper machine.

[0251] As shown in Table 2, samples 2 and 3 were processable and had high strength, stiffness, and temperature resistance after processing. Sample 1 has a lower processing difficulty and a lower temperature resistance.

[0252] EXAMPLE 2 This example sets out the various tests conducted to assess the physical properties of different fiber web samples. Samples 1, 2, and 3 are the same samples 1, 2, and 3 reported in Example 1. Sample 5 is a fiber web including 35 wt% chopped strand glass fibers, 15 wt% bicomponent fibers, and 50 wt% microglass fibers, giving it an identical fiber makeup to Sample 3 and prepared by the same process. However, Sample 5 and Sample 3 were prepared to have different basis weights. The basis weights of Samples 1-3 and 5 are reported in Table 3 below.

[0253] Samples 1-3 and 5 were tested to determine a wide variety of physical properties. - I l l -

[0254] The basis weight, tensile strength, and % elongation of the samples was measured according to methods described above. The density and thickness of the samples in both no-contact and lOkPa pressure conditions were also measured according to standard methods, as described above. Finally, the mean, minimum, and maximum pore sizes of each sample was determined according to standard methods, as described above. The physical properties of each sample are summarized in Table 3. All fiber webs were observed to have relatively large pores and relatively low densities, but the largest pores and lowest 10 kPa densities were observed in sample 1, which included the highest proportion of microglass fibers.

[0255] Table 3 - Physical properties of fiber web samples.

[0256] The thermal stability of Samples 1-3, discussed qualitatively in Table 2, was also quantified by measuring thermal shrinkage at conditions of 540°C for 1 minute and 650°C for two hours, according to methods discussed in greater detail above. The shrinkage in both machine direction (MD) and cross direction (CD) was measured and reported in Table 4.

[0257] Table 4 - Thermal stability of fiber web samples.

[0258] As reported qualitatively in Example 1, Samples 2 and 3 experienced relatively low thermal shrinkage, compared with Sample 1. The reduction in thermal shrinkage may, in some embodiments, be related to the relatively high amount of chopped strand glass in Samples 2 and 3, relative to Sample 1.

[0259] Examples 1 and 2 demonstrate that fiber webs including glass fibers can be prepared to have suitable mechanical and thermal properties for use in electrode media. Furthermore, Examples 1 and 2 demonstrate particular advantages associated with the use of multiple pluralities of glass fibers of different types.

[0260] EXAMPLE 3

[0261] This example sets out various tests carried out on fiber webs including glass fibers, in order to determine whether metal lugs could be attached to the fiber webs, and to test whether the fiber webs could be pasted in order to form a battery plate. Samples 6 and 7 were commercially available fiber webs as, detailed below. Sample 8 had the fiber composition of Sample 1 as set forth in Table 2 above, including 10 wt% chopped strand glass fibers, 15 wt% bicomponent fibers, and 75 wt% microglass fibers. During processing, Sample 8 was plastically formed to have a thickness of less than 1.5 mm, as set forth in the tables described below. Sample 9 had the fiber composition of Sample 3 set forth in Table 2 above, including 35 wt% chopped strand glass, 15 wt% bicomponent fibers, and 50 wt% microglass fibers. During processing, Sample 9 was plastically formed to have a thickness of less than 1.7 mm, as set forth in the tables described below.

[0262] Each fiber web was cut to the size of an electrode. Each fiber web was tested to determine the ability of the fiber web to receive a lug. If the fiber web could receive a lug, then it underwent a pasting process to form an electrode.

[0263] For lug formation, each fiber web underwent a pressure impregnation process using molten lead as the lug material. Each fiber web was passed through a lug forming machine where molten lead was provided to one edge of the glass fiber sample.

[0264] For the fiber webs that could receive a lug, the fiber web was then moved on to the pasting step. For pasting, an 86% leady oxide paste was made by first mixing the amount of leady oxide with an expander in a bowl. The remaining ingredients (see Table 5 below) were then added to the bowl. Mixing was recommenced after addition of the remaining ingredients. A total mixing time of the paste did not exceed 15 minutes. This resulted in a paste, which was then used to manually paste the fiber web samples. Manual pasting was performed by placing the fiber web on an ultrasound plate and spreading the paste onto the surface of the fiber web. The ultrasound plate was turned on to vibrate the paste into the fiber web for approximately ~1.5 - 2.0 min. During pasting, each fiber web was turned over one or more times to reverse a direction of paste-flow, until a smooth distribution of paste was observed across the surface of the glass fiber. The smooth paste distribution indicated that the majority of the paste had penetrated into the fiber web.

[0265] Table 5 - Paste ingredients.

[0266] Ingredients

[0267] Leady oxide (%) Leady oxide (g) Barium sulfate (g) H2SO4 (g) Water (g) Expander (g)

[0268] 86% 44,790 358.3 223 6,875 383 The results of lug formation and pasting are set out in Table 6 below, along with a description of each tested fiber web.

[0269] Table 6 - Results.

[0270] Fiber web Able to receive Able to Observations

[0271] Samples lug be pasted

[0272] Sample 6 No N / A Unsuccessful - once heat applied, fiber web melted

[0273] Owens Corning and disintegrated. This sample fiber web could not

[0274] Grade 731ED proceed to pasting.

[0275] Sample 7 Yes Yes Successful. This sample fiber web could receive a lug

[0276] Frenzelit IsoGLAS and was able to be pasted. needlemat This pasted and lugged web went on to be used in a

[0277] 3mm thick, 1N / 2P battery.

[0278] 360g / m2

[0279] Sample 8 Yes, but fell apart N / A Unsuccessful - fiber web could receive a lug,

[0280] 10 wt% chopped on removal from however it disintegrated upon removal from lug strand glass, 15 lug machine machine. This sample fiber web could not proceed to pasting. wt% bicomponent, 75 wt% microglass 1.42 mm thick, 240g / m2

[0281] Sample 9 Yes Yes Successful. This sample fiber web could receive a lug

[0282] 35 wt% chopped and was able to be pasted. strand glass, 15 This pasted and lugged fiber web went on to be used wt% bicomponent, in a 6P / 7N battery

[0283] 50 wt% microglass 1.7 mm thick, 220g / m2

[0284] Only Samples 7 and 9 were both sufficiently heat stable to receive a lug and had sufficient strength to be pasted. Although Sample 7 was able to receive a lug, the interface between the lug and the fiber web was structurally weak. This example demonstrates that not all fiber webs including glass fibers are capable of receiving a lug. For example, a fiber web like Sample 6 or Sample 8 may lack the requisite thermal stability to receive a lug. Furthermore, this example demonstrates that the high thermal stability of fiber webs described in earlier examples may be a good proxy for the ability of a fiber web to receive a lug. For example, Sample 9 included both chopped strand glass and microglass in weight percentages demonstrated to have good thermal stability in earlier examples — and Sample 9 was the only sample to survive the lug formation process with a high quality lug.

[0285] EXAMPLE 4

[0286] This Example describes the performance of Samples 7 and 9 after formation into lugged battery plate and incorporation into a lead acid battery.

[0287] Battery plates including lugged and pasted Samples 7 and 9 were flash dried to achieve a moisture content of between 9-13%. The battery plates were then cured in a humidity and temperature-controlled curing oven to create dry unformed (DUF) electrodes. A 1N / 2P battery was constructed by assembling one negative and two positive (1N / 2P) cells using a DUF electrode made from Sample 7 with two commercially available traditional positive electrodes and a Daramic DuraLife® (a polyethylene battery separator) separator placed between each pair of electrodes. A matched 1N / 2P battery control (without a fiber web) was made using commercially available traditional positive and negative electrodes in the dry unformed state with a Daramic DuraLife® (a polyethylene battery separator) separator in between.

[0288] A 2V 60Ah battery (nominal capacity) battery was constructed by assembling a battery with 6 negative, seven positive (6N / 7P) cells using...

Claims

CLAIMSWhat is claimed is:

1. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, and have an average length of less than or equal to 0.5 mm, an average diameter of greater than or equal to 0.1 microns and less than or equal to 15 microns, and an average aspect ratio of less than or equal to 50; a second plurality of fibers, wherein the second plurality of fibers are staple fibers and have an average diameter of greater than or equal to 1 micron; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron; wherein the first plurality of glass fibers makes up greater than or equal to 2 wt% and less than or equal to 99 wt% or greater than or equal to 15 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; wherein the second plurality of fibers makes up greater than 0 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; and wherein the plurality of multicomponent fibers makes up greater than or equal to 0 wt% and less than or equal to 50 wt% of the total weight of the fibers of the fiber web.

2. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, and have an average length of less than or equal to 0.5 mm, an average diameter of greater than or equal to 0.1 microns and less than or equal to 15 microns, and an average aspect ratio of less than or equal to 50; a second plurality of glass fibers, wherein the second plurality of glass fibers are chopped strand fibers and have an average diameter of greater than or equal to 1 micron; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron;wherein the first plurality of glass fibers makes up greater than or equal to 2 wt% and less than or equal to 99 wt% or greater than or equal to 15 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; wherein the second plurality of glass fibers makes up greater than 0 wt% and less than or equal to 90 wt% of the total weight of the fibers of the fiber web; and wherein the plurality of multicomponent fibers makes up greater than or equal to 2 wt% and less than or equal to 20 wt% of the total weight of the fibers of the fiber web.

3. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web, comprising: a plurality of glass fibers; and a plurality of multicomponent fibers, wherein the plurality of multicomponent fibers has an average diameter of greater than or equal to 1 micron; wherein the plurality of multicomponent fibers makes up greater than or equal to 2 wt% and less than or equal to 20 wt% of the total weight of the fibers of the fiber web, and wherein the multicomponent fibers are present at a first edge of the fiber web and absent from a second edge of the fiber web.

4. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web comprising: a first plurality of glass fibers, and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; wherein a plasticity of the fiber web is greater than or equal to 5%, and wherein a basis weight of the fiber web is greater than or equal to 40 gsm.

5. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web comprising: a first plurality of glass fibers, anda second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; wherein a tensile strength of the electrode media is greater than or equal to 2 Ib / inch, wherein an elongation at break of the electrode media is greater than or equal to 1%, and wherein a basis weight of the fiber web is greater than or equal to 40 gsm.

6. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web, comprising: a first plurality of glass fibers, wherein the first plurality of glass fibers are microglass fibers, a second plurality of glass fibers, wherein the second plurality of glass fibers are chopped strand fibers or drawn fibers, and a plurality of multicomponent fibers, wherein the fiber web has a maximum pore size of greater than or equal to 20 microns, a density of less than or equal to 250 gsm / mm, and a tensile strength of greater than or equal to 2 Ib / inch.

7. An electrode for use in a lead acid battery, the electrode comprising: a fiber web comprising: a first plurality of glass fibers; and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers, wherein the fiber web comprises a plurality of pores, wherein an active material is impregnated into the plurality of pores of the fiber web, and wherein the fiber web has a thickness of greater than or equal to 0.25 mm.

8. An electrode for use in a lead acid battery, the electrode comprising:a fiber web comprising: a first plurality of glass fibers and a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, natural fibers, or glass fibers different from the glass fibers of the first plurality of glass fibers; and an electrically conductive lug interpenetrating with a boundary portion of the fiber web.

9. An electrode for use in a lead acid battery, comprising: a fiber web comprising: a plurality of glass fibers; and a plurality of non-glass fibers, wherein an active material is impregnated into a plurality of pores of the fiber web.

10. An electrode media for use in a lead acid battery, the electrode media comprising: a fiber web comprising: a plurality of glass fibers, and a plurality of staple fibers configured to mechanically reinforce the fiber web, and wherein the fiber web shrinks by less than or equal to 25% when held in air at a temperature of 650 °C for 2 hours.

11. An electrode for use in a lead acid battery, the electrode comprising: a fiber web comprising: a plurality of glass fibers and a second plurality of non-glass fibers; and an electrically conductive lug interpenetrating with a boundary portion of the fiber web; wherein an active material is impregnated into said fiber web.

12. The electrode media or electrode of any one of the preceding claims, wherein the staple fibers are glass fibers or carbon fibers.

13. The electrode media or electrode of any one of the preceding claims, wherein the staple fibers are chopped strand glass fibers or drawn fibers.

14. The electrode media or electrode of any one of claims 4-5, 7-9, and 11-13, wherein the second plurality of fibers is a plurality of multicomponent fibers.

15. The electrode media or electrode of any one of claims 9-13, further comprising a plurality of multicomponent fibers.

16. The electrode media or electrode of any one of claims 1-3, 6, and 14-15, wherein the plurality of multicomponent fibers binds the pluralities of fibers in the fiber web.

17. The electrode media or electrode of any one of the preceding claims, wherein the glass fibers of the first plurality of glass fibers control a pore structure of the fiber web.

18. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a basis weight of greater than or equal to 40 gsm.

19. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a thickness of greater than or equal to 0.25 mm.

20. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers has an average diameter of greater than or equal to 0.1 microns and less than or equal to 15 microns.

21. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers has an average diameter of less than or equal to 5 microns.

22. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers has an average aspect ratio of less than or equal to 50.

23. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Li in an amount of less than or equal to 5 wt ppm.

24. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Pb in an amount of less than or equal to 15 wt ppm.

25. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Sr in an amount of less than or equal to 90 wt ppm.

26. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Te in an amount of less than or equal to 15 wt ppm.

27. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Zr in an amount of less than or equal to 10 wt ppm.

28. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Co in an amount of less than or equal to 5 wt ppm.

29. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Cr in an amount of less than or equal to 15 wt ppm.

30. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Cu in an amount of less than or equal to 5 wt ppm.

31. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Fe in an amount of less than or equal to 150 wt ppm.

32. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Mn in an amount of less than or equal to 10 wt ppm.

33. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Ni in an amount of less than or equal to 5 wt ppm.

34. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers comprises Ti in an amount of less than or equal to 15 wt ppm.

35. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of fibers is a plurality of glass fibers different from the glass fibers of the first plurality of glass fibers.

36. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Li in an amount of less than or equal to 5 wt ppm.

37. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Pb in an amount of less than or equal to 15 wt ppm.

38. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Sr in an amount of less than or equal to 90 wt ppm.

39. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Te in an amount of less than or equal to 15 wt ppm.

40. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Zr in an amount of less than or equal to 10 wt ppm.

41. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Co in an amount of less than or equal to 5 wt ppm.

42. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Cr in an amount of less than or equal to 15 wt ppm.

43. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Cu in an amount of less than or equal to 5 wt ppm.

44. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Fe in an amount of less than or equal to 150 wt ppm.

45. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Mn in an amount of less than or equal to 10 wt ppm.

46. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Ni in an amount of less than or equal to 5 wt ppm.

47. The electrode media or electrode of any one of the preceding claims, wherein the second plurality of glass fibers comprises Ti in an amount of less than or equal to 15 wt ppm.

48. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers has an average diameter of less than or equal to 5 microns.

49. The electrode media or electrode of any one of the preceding claims, wherein the first plurality of glass fibers has an average length of less than or equal to 0.5 mm.

50. The electrode media of any one of the preceding claims, further comprising an active material at least partially impregnated within pores of the fiber web.

51. The electrode media or electrode of any one of claims 1-10 and 12-49, further comprising a lug zone comprising a metal lug material at least partially surrounding some fibers of the fiber web.

52. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a maximum pore size of greater than or equal to 20 microns.

53. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a density of less than or equal to 160 gsm / mm.

54. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a strength of greater than or equal to 2 Ibs / inch.

55. The electrode media or electrode of any one of the preceding claims, wherein greater than or equal to 90% of the fibers of the fiber web are electrically non-conductive fibers having a minimum resistivity of greater than or equal to 102ohm-centimeters.

56. The electrode media or electrode of any one of the preceding claims, wherein greater than or equal to 90% of the fibers of the fiber web are electrically non-conductive fibers having a minimum resistivity of greater than or equal to 108ohm-centimeters.

57. The electrode media or electrode of any one of the preceding claims, wherein the fiber web is a non-woven fiber web.

58. The electrode media or electrode of any one of the preceding claims, wherein a plasticity of the fiber web is greater than or equal to 5%.

59. The electrode media or electrode of any one of the preceding claims, wherein a basis weight of the fiber web is greater than or equal to 40 gsm.

60. The electrode media or electrode of any one of the preceding claims, wherein an elongation at break of the electrode media is greater than or equal to 1%.

61. The electrode media or electrode of any one of the preceding claims, wherein the fiber web shrinks by less than or equal to 25% when held at a temperature of 650 °C in air for 2 hours.

62. The electrode media or electrode of any one of the preceding claims, wherein the plurality of staple fibers has a normally distributed length.

63. The electrode media or electrode of any one of the preceding claims, wherein the average length of the plurality of staple fibers and the median length of the plurality of fibers differ by no more than 5%.

64. The electrode media or electrode of any one of the preceding claims, wherein staple fibers have an average length of greater than or equal to 2mm and less than or equal to 300mm.

65. The electrode media or electrode of any one of the preceding claims, wherein chopped strand fibers have an average length of greater than or equal to 2mm and less than or equal to 300mm.

66. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a mean flow pore size of greater than or equal to 10 microns.

67. The electrode media or electrode of any one of the preceding claims, wherein the fiber web has a mean flow pore size of greater than or equal to 30 microns.

68. The electrode of any one of the preceding claims, wherein at greater than or equal to 5% of the active material of the electrode is interpenetrated into the fiber web.

69. The electrode media or electrode of any one of the preceding claims, wherein the fiber web comprises a plurality of synthetic monocomponent fibers.

70. The electrode media or electrode of claim 69, wherein the plurality of synthetic monocomponent fibers comprises polyvinyl alcohol (PVA).

71. An electrochemical cell comprising the electrode media or electrode of any one of the preceding claims.

72. A battery comprising the electrode media or electrode or electrochemical cell of any one of the preceding claims.

73. A vehicle comprising the electrode media or electrode or electrochemical cell or battery of any one of the preceding claims.

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