Carbon nanotubes-polymer composite for dry processed battery electrodes

Abstract

A solvent-free process employs a composite that includes carbon nanotubes and a polymer to prepare compositions and electrodes for lithium-ion batteries. The carbon nanotubes in the composite can be multifunctional, providing two or more desirable characteristics, acting, for example, as a conductive carbon additive, as a processing, e.g., fibrillizing, agent and / or as a mechanical reinforcement. The composite can be combined with an electroactive material and a binder; the binder can be processed, e.g., fibrillated, in the presence of the carbon nanotubes in the composite. The resulting composition can be formed into a film which can be applied onto a suitable substrate to form an electrode.

Description

Docket: 2022622PCTTITLECarbon Nanotubes-Polymer Composite for Dry Processed Batery ElectrodesCROSS-REFERENCE TO RELATED APPLICATIONS[ ooi] This application claims the benefit under 35 USC 119 of U. S. Provisional Application No. 63 / 569,822 filed on March 26, 2024, the disclosure of which is hereby incorporated herein by reference in its entirety.BACKGROUND[ o 02 ] Lithium-ion batteries (LIBs) are commonly used sources of electrical energy for numerous applications ranging from electronic devices to electric vehicles. A lithium-ion battery typically includes a negative electrode and a positive electrode in an arrangement that allows lithium ions and electrons to move to and from the electrodes during charging and discharging. An electrolyte solution in contact with the electrodes provides a conductive medium in which the ions can move. To prevent direct reaction between the electrodes, an ion-permeable separator is used to physically and electrically isolate the electrodes. During operation, electrical contact is made to the electrodes, allowing electrons to flow through the device to provide electrical power, and lithium ions to move through the electrolyte from one electrode to the other.

[0003] Most commercially available lithium-ion batteries have anodes that contain graphite, a material capable of incorporating lithium through an intercalation mechanism. Typically, lithium is added to the graphite anode during the charging cycle and removed as the battery is used. Other anode materials used in addition to or alternatively to graphite include lithium titanate, tin oxide, silicon (Si) and SiOx (with x typically being 1.04, 1.06, etc.). In illustrative examples the anode includes graphite and / or a silicon-containmg compound. [ o 04 ] Cathodes include a conductive substrate supporting a mixture containing at least an electrochemically active material and a binder. The electroactive material, such as a lithium transition metal oxide, is capable of receiving and releasing lithium ions. As with the anode, the binder is used to provide mechanical integrity and stability to the electrode.Docket: 2022622PCT

[0005] Since the electroactive material and the binder often display poor electrically conducting or even insulating properties, cathodes often include an additive component which enhances the electrical conductivity of the electrode. Conductive additives, carbon conductive additives, for instance, also can be found in LIB anode compositions.

[0006] To manufacture the electrode, the active electrode material is mixed with a binder, typically a polymeric or resin material. Many existing fabrication methods employ casting techniques based on wet slurries that contain not only the binder but also solvents, plasticizers, conducive additives, and so forth. During manufacturing, the slurry is coated or extruded onto a conductive substrate. Since the solvent is detrimental to the final product, it is removed by drying,[ o 07 ] However, drying operations, in particular those aimed at solvent removal, require time, slowing down the overall production process. Also, they can raise costs as well as environmental concerns. In terms of the end product, the removal of the solvent during the drying process often leads to migration of the binder to the surface of the electrode. Though minimal migration can be acceptable in some cases, it is problematic in others. For high loadings (thick, > 4.5 mAh / g) electrodes, for instance, the migration is exacerbated, leading to delamination and poor electrode performance.[ o o 8 j As a result, “dry” alternatives, aiming at reducing or eliminating the diving step associated with slurry techniques, are being developed. While dry processes also produce electrodes that typically contain an electroactive material, binder and a conductive additive component, they do not require using a solvent.

[0009] Dry approaches that have been proposed include high shear mixing involving fibrillizable binder, use of sacrificial binder removed upon processing of the electrode, dry powder spraying, electrostatic spray deposition, cold plasma deposition, sputtering deposition, powder printing, to name a few. In some, a fibrillization promoter is incorporated into the binder and the resulting formulation is subjected to high shear mixing to fibrillate the binder, thereby generating a web-like structure that can better hold the materials together and support the active material.Docket: 2022622PCT[ o o 1 o i To date, the most common additive used to promote binder fibriliization has been activated carbon (AC). Generally, AC is derived from carbonaceous source materials such as bamboo, coconut husk, willow peat, wood, coir, lignite, coal, and petroleum pitch. Activation is achieved by physical or chemical approaches, as known in the art. For many applications, AC powders are milled to tens of micron (pm) particle dimensions prior to activation.SUMMARY[00111 While dry manufacturing processes have the potential of eliminating many of the challenges posed by the addition and / or removal of solvents (often harmful), problems remain.[ 0012 i For example, many “dry” fabrication techniques utilize not only the active electrode material but many other ingredients such as fibriliization promoters, conductive additives and binders. Since many of these components are not involved in the electrochemical reactions that generate electrical energy, they can negatively affect certain performance characteristics (e.g., capacity and energy density) of the battery, as they effectively iower the amount of active material that can be contained in a given volume.[0013 i State of the art fibriliization agents such as ACs often contain high impurity levels. Also, high surface areas and surface oxygen-containing groups that are typical for ACs tend to promote significant water uptake. These features can contribute to irreversible capacity losses, diminishing battery performance. Furthermore, ACs fail to add sufficient conductivity, raising the need for increased amounts of conductive additives in the overall formulation. Even as a simple fibriliization promoter, AC often requires relatively high loadings (5 to 10 weight %, in many cases) and this, in and of itself, also limits the amount of active materials that can be included.

[0014] It was discovered that AC can be supplemented and often entirely replaced by carbon nanotubes (CNTs), as described, for example, in International Patent Application No. PCT / US24 / 20620, filed on March 20, 2024, incorporated herein in its entirety’ by this reference.

[0015] For many applications, the CNTs can have a multifunctional character, providing two or more desirable features. For example, the carbon nanotubes can act as a fibrillizing aid,Docket: 2022622PCTserving as an AC substitute; as conductive carbon additive (by forming electrically conductive networks); and / or as a mechanical reinforcement, adding mechanical strength and flexibility to a product film / electrode.

[0016] One problem faced during the solvent-free mixing of CNTs with other ingredients, however, relates to the potential release of airborne particulates, posing health and safety concerns. With a total weight average (TWA) exposure limit of 1 micrograms per cubic meter (pg / m3) of particulates in 8 hours, emissions of CNTs-derived particulates can become problematic for industrial- scale manufacturing. Another challenge is the limited dispersibility of CNTs.

[0017] A need exists, therefore, for compositions and processes that address at least some of these issues.

[0018] Ingredients involved in the process, composition and / or articles described herein include: an electroactive component (a material or combination of materials that participates in the electrochemical charge / discharge reactions of an electrochemical cell such as by absorbing or desorbing lithium), a binder, and CNTs. In specific embodiments, the CNTs are provided as a constituent in a CNTs-polymer composite. In one example, the polymer in the CNTs- polymer composite is PTFE. In another, the polymer is polyvinylpyrrolidone (PVP). Other polymeric materials can be employed.[0019 i In many of the embodiments disclosed herein, the CNTs-polymer composite is prepared in the presence of a liquid, in an aqueous medium, for instance. For example, the CNT component, the polymer component, or both can be provided in a dispersion and combined to form a mixture that is then dried. The process can further include an agglomeration step, often conducted prior to the drying operation, in which fine CNTs- polymer particles are clustered together or “pelletized” to form entities of larger dimensions. In one example, the CNTs-polymer pellets have a particle size within a range from about 0.5 to about 30 millimeter (mm) in either direction.[ o 020 i The CNTs-polymer composite can be used to prepare an electrode composition in a dry or solvent-free process that involves combining the electroactive material, the binder, and the CNTs-polymer composite, and processing the binder (and, in some cases, also the polymerDocket: 2022622PCTin the composite) in the presence of CNTs. In general, the binder can be any semi-crystalline polymer. Accordingly, the method can be conducted with binders conventionally thought of as “fibrillizable” as well as with those conventionally considered as “non-fibrillizable” binders; combinations thereof also can be utilized,[ o 021 1 Typically, the dry process described herein is conducted without using any liquid (a solvent, for instance). In many embodiments, ingredients, including the CNTs-polymer composite, are provided as loose particulate materials such as flowing or pourable powders, flakes, beads, granules, pellets and so forth.[ o 022 i However, it is possible, in some cases, to use small amounts of liquid (solvent, for instance) to carry out the method described herein, typically in a step other than the fibrillating or binder processing step. Generally, if liquid is being added, amounts employed are no greater than about 10 wt % of the total weight amount of ingredients used. Often, liquid, e.g,, solvent, is added in an amount that is no greater than 1 wt %.[ 00231 Thus, in one implementation, a method for preparing an electrode composition comprises: combining an active electrode material, a fibrillizable binder, and a CNTs-polymer composite, and processing the binder in the presence of the CNTs-polymer composite, wherein the method is conducted in the absence of solvent.[ 0024 J In another implementation, a method for preparing an electrode composition comprises: processing a binder (subjecting the binder to high shear conditions, for example) in the presence of a CNTs-polymer composite, and adding an electrode active material before, during or after binder processing, wherein the method is conducted without adding a solvent.[ 0025 J The electroactive material, the binder, e.g., a fibrillizable binder, and the CNTs- polymer composite can be combined in a single step, followed by the binder processing, a fibrill ization operation, for instance. In other embodiments, the constituents are combined and / or processed sequentially. For example, the binder, in the presence of the CNTs-polymer composite, can be processed, e.g., fibrillized, first, this step being followed by mixing with the electroactive material. Other sequences are possible.Docket: 2022622PCT[ 0026 i Uniform distributions of constituents can be obtained using conditions other (often milder) than those utilized in the binder processing, e.g., fibril lization. Low shear mixing techniques also can prevent particle fragmentations, thus preserving particle size.[ 0027 j In specific embodiments, the method described herein is conducted without adding any fibrillating aid other than the CNTs in the CNTs-polymer composite. In such a case, the CNTs provide the entire binder processing (e.g., fibrillating) functionality, completely replacing conventional fibrillating agents such as activated carbons, for instance. It is also possible to use the CNTs in the CNTs-polymer composite in combination with various amounts of a conventional fibrillizmg aid, such as an activated carbon, for example.

[0028] The resulting electrode composition, typically a loose particulate material, can be further processed. For example, the composition can be formed into a free-standing film that can be applied to an electrically conductive substrate or support to form an electrode. In one approach, the composition is calendared and laminated to a conductive foil substrate. The calendaring operation can be conducted at or above room temperature, e.g., at a temperature similar or close to the binder polymer glass transition temperature. The lamination step can be performed during or after the composition is calendared. The resulting product electrode can be assembled into a LIB battery.[ 0029 J In a further aspect, the disclosure features a dry processed film which includes an active electrode material; a binder, typically processed, e.g., fibnlhzed; and CNTs (initially supplied as a CNTs-polymer composite). Also present in the dry processed film is the polymer m the CNTs-polymer composite, a constituent which can be identified in some cases (when using a polymer that is different from the binder, for example). Before any drying operation, the dry processed film has a weight that is the same as or within 1 % by "weight (wt %) of its theoretical weight.[ o o 3 o i The CNTs-polymer composite described herein facilitates the incorporation of CNTs into electrode compositions, without needing to rely on slurry-based fabrication techniques. Delivering CNTs in a dry CNTs-polymer composite also addresses health and safety concerns that may arise in the context of solvent-free manufacture. In some implementations, the polymer in the CNTs-polymer composite and the polymer in the binderDocket: 2022622PCTcomponent are compatible with each other, facilitating mixing, easing binder elongation and fibrill izati on, improving binder distribution in-between other electrode components and throughout the electrode. Providing CNTs bound in a polymer matrix yields products (films or electrodes, for instance) that perform at least as well as products prepared with polymer-free CNTs.

[0031] Using CNTs can bring about a number of attractive properties to a dry processed electrode film and / or electrode, including, for example, electrical conductivity', attractive physical properties, e.g., good tensile strength, thermal stability (sometimes comparable to that of diamond crystals or in-plane graphite sheets) and / or chemical stability, to name a few. Adding CNTs can reduce the amount of binder and / or conventional processing additives required in the fabrication process, increasing the potential loading with active materials and leading to higher energy density electrodes and therefore batteries.[ o 032 i Approaches described herein can reduce or eliminate the need for ACs. In many cases, smaller additive amounts are needed, increasing the available content allowed for active electrode materials, yielding batteries with higher energy densities and longer lifetimes. The CNTs can improve binder fibrillization and material distribution across the electrode.Enhanced adhesion and mechanical stability represent yet other potential benefits. Dry- processed electrodes prepared using a CNTs-polymer composite are expected to exhibit good charge transfer. The reduction in electrode impedance with a ( / NT additive can improve cell rate capacity and charging performance, opening opportunities for thicker electrodes and higher energy density batteries with fast charging capabilities.

[0033] In some cases, the initial CNTs present in the composite may be broken or separated into smaller units during processing. It is believed that such fragments, distributed, e.g., uniformly, throughout an electrode composition, can lead to electrodes with improved mechanical properties and / or electrical connectivity (by forming enhanced electrical pathways) in the resulting electrode.[ o 034 i Whereas binder migration phenomena are often observed with slurry -prepared electrodes, the process and composition described herein appear to yield uniform distributions across the electrode. The fibrillated binder keeps the electroactive particles (along with theDocket: 2022622PCTconductive additives) together (cohesion), while also keeping the electrode film layer attached to the metal substrate (adhesion).

[0035] The solvent-free techniques described herein reduce or eliminate the use of harmful solvents such as N-inethyl-2-pyrrohdone (NMP) and the like. Being able to bypass the drying step associated with slurry (or other “wet” processes) can simplify and speed up manufacture and reduce the footprint of the electrode production tine. These benefits, as well as reducing or eliminating the need for solvent recycling or emissions abatement measures can contribute to overall cost reductions.[ 0036 i The above and other features of the disclosure including various details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the disclosure are shown by¬ way of illustration and not as a limitation of the disclosure. The principles and features of this disclosure may be employed in various and numerous embodiments without departing from the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS[ o 037 i In the accompanying drawings, reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale: emphasis has instead been placed upon illustrating the principles of the disclosure. Of the drawings:[ 0038 i FIG. 1A is a schematic diagram and corresponding photograph of a pelletized CNT / polymer composite:

[0039] FIG. I B is a schematic diagram of an intermediate product;[ 0040 i FIG. 1C is a schematic diagram and corresponding photograph of a fibnlized product;

[0001] FIG. ID is a series of photographs of a free standing film prepared using the fibrilized product of FIG 1C;Docket: 2022622PCT[ 0042 i FIG. 2 shows bar charts comparing the tensile strength of dry cathode films prepared with pelletized CNT1 / PVP composite, CNT2 / PTFE composite, and pristine (non¬ pelletized) CNT1;

[0043] FIG. 3 includes bar charts comparing the tensile strength (bottom) and elastic modulus (top) of dry cathode films prepared with non-pelletized CNT2, non-pelletized CNT3 and a pelletized CNT3 / PVP-1 composite;[ 0044 i FIG. 4 includes bar charts comparing the tensile strength (bottom) and elastic modulus (top) of dry cathode films made with pelletized CNT3 / PVP composites at different CNT to PVP weight ratios;

[0045] FIG. 5 is a plot showing the 0.5C / 0.1C discharge capacity retention of full coin cells with dry cathodes prepared using pelletized CNT3 / PVP-1 composite and pelletized CNT3, in comparison with non-pelletized CNT2 and non-pelletized CNT3;[ 0046 i FIG. 6A is a plot showing the C / 3 capacity cycling of full coin cells with dry cathodes prepared using CNT3 alone and a CNT3 / PVP-1 composite up to 330 cycles;[ 0047 i FIG. 6B presents the number of cycles for cell capacity to drop by 20%, calculated by fitting the linear region of the curves shown in FIG. 6A.[ 0048 i FIG. 6C is a plot showing capacity retention comparison of the cells with dry cathodes prepared with pelletized CNT3ZPVP-1 composite, pelletized CNT3, non-pelletized CNT2, and non-pelletized CNT3;

[0009] FIG.7 shows bar charts comparing the tensile strength of dry cathode films prepared with (i) pelletized CNT3, or (ii) with the pristine (non-pelletized) using TSE;

[0050] FIG. 8 shows SEM images of the cross section of the electrode made with pelletized CNT3 and zoomed-in surface of one NCM particles (left) in this electrode, and F. DS mapping of F and C (right);[ 0051 FIG. 9 shows rate capability of dry cathodes made with pelletized CNT3 and non- pelletized pristine CNT2 using TSE, tested in full coin cells.Docket: 2022622PCTDETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] The disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the disclosure are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and wall fully convey the scope of the disclosure to those skilled in the art.[0053 i As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Also, all conjunctions used are to be understood in the most inclusive sense possible. Thus, the word "or" should be understood as having the definition of a logical "or" rather than that of a logical "exclusive or" unless the context clearly necessitates otherwise. Further, the singular forms and the articles "a", "an" and "the" are intended to include the plural forms as well, unless expressly stated otherwise. It wall be further understood that the terms: includes, comprises, including and / or comprising, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Further, it will be understood that when an element, including component or subsystem, is referred to and / or shown as being connected or coupled to another element, it can be directly connected or coupled to the other element or intervening elements may be present,

[0054] It will be understood that although terms such as “first” and “second” are used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, an element discussed below could be termed a second element, and similarly, a second element may be termed a first element without departing from the teachings of the present disclosure.[ o 055 i Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent withDocket: 2022622PCTtheir meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0056] The disclosure generally relates to the manufacture of electrodes for electrochemical cells, in many cases for batteries such as, for instance, LIBs. In one example, the batteries of interest are rechargeable LIBs. In addition, principles described herein can be applied or adapted to lithium metal batteries, for instance, lithium-sulfur batteries that include a sulfur-containing cathode, to solid state batteries (SSB), or other devices.

[0057] Typically, LIB batteries are named according to the acronyms for the electroactive material employed to form the cathode, often an intercalation compound. Embodiments described herein can be practiced with or adapted to various types of lithium-ion batteries currently known in the art, such as, for example, LCO (lithium cobalt oxide), LMO (lithium manganese oxide), NCM (lithium nickel cobalt manganese oxide), NCA (lithium nickel cobalt aluminum oxide), LCP (lithium cobalt phosphate), LFP (lithium iron phosphate), LFMP (lithium iron manganese phosphate), LFSF (lithium iron fluorosulfate), LTS (lithium titanium sulfide) or LIBs being developed currently or in the future.[ 0058 j Many electrode manufacturing techniques for use in an electrochemical cell include the formation of an electrode composition (anode or cathode) that can be applied (coated, extruded, laminated, etc.) onto a conductive substrate. In the composition, the active electrode material is mixed (blended) with a binder (e.g., polymers, resins, etc.), which serves to associate and hold together the active materials. Liquids used to dissolve or carry the binder material, plasticizers and / or other additives often are included.

[0059] Generally, in a conventional solvent-based process, the polymer binder and other components are mixed with a suitable liquid to form a slurry that can then be applied onto the substrate. Typical liquid amounts employed are at least about 40 % based on the total weight of the ingredients used; many wet processes require higher solvent amounts. As the solvent is removed (e.g., during drying), the binder becomes increasingly sticky and adheres to the particles present and / or the substrate.

[0060] In contrast to slurry-based techniques, embodiments described herein involve a “solvent-free” also referred to as a “dry” process. In this solvent-free approach, some andDocket: 2022622PCTtypically all constituents (e.g., active material, binder, additives, etc.) needed to prepare the electrode composition are provided as loose particulate materials, e.g., free flowing powders, flakes, pellets, beads, and so forth. Implementations described herein can include one or more operations designed to mix these constituents (using, for instance, equipment designed to blend loose particulate materials) as well as at least one operation designed to process the binder. Subjecting the binder to certain shear conditions, for example, can result in binder deformations, e.g,, binder elongations, binder strands, entanglements, and so forth. With some types of binders, this is referred to as binder “fibrillization”.[0061: In many aspects of the disclosure, ingredients are combined, and the binder is processed, e.g., fibrillized, without adding any liquid, e.g., solvent,[ 0062 i While most embodiments involve a process that is conducted without liquid addition and is completely solvent free, small amounts of liquid, e.g., solvent, can be used in some cases, to moisten, for instance, at least some of the particles being mixed. This may occur, for instance, when forming a pre-blend that is then completely dried prior to conducting subsequent operations. In one example, any solvent used to form such as pre-blend is removed, e.g., by drying, before the binder is deformed. Processing (e.g., fibrillizing) the binder is then conducted with loose, free flowing or pourable particles, under entirely solvent- free conditions.[ o o 63 i Solvent can also be used in a post operation (an operation that takes place after the dry electrode composition has been formed) such as, for example, during film fabrication or electrode lamination, e.g., to facilitate film processibility. Electrode production protocols will, in some cases, call for a small amount of solvent, to “wet” the film during calendaring, for instance. Processes that involve solvent use in a post operation, after the electrode composition has been formed, also are referred to herein as “dry” or “solvent-free”.Generally, any solvent employed (to spray the film during film fabrication of lamination, for instance) is removed, e.g., by drying, as the electrode is passed through heated calendar rolls.[ o 064 i Suitable solvents can be selected from solvents typically encountered in LIB production and include but are not limited to N-methylpyrrolidone (NMP), acetone, alcohols, and water.Docket: 2022622PCT

[0065] For many applications, the amount of solvent employed is no greater than about and often less than 1 weight % of the entire product electrode composition (a composition containing electroactive material, processed, e.g., fibrillized, binder and other ingredients, an additive component, for instance). In illustrative examples, the amount of solvent employed is within a range of from about 0 to at most 1 wt %, such as from about 0 to about 0.2, to about 0.-4, to about 0.6, to about 0,8 wt %; or from about 0.2, to about 0.4, to about 0.6, to about 0.8, to about 1 wt %; or from about 0.2 to about 0.4, to about 0.6, to about 0.8, to about 1 wt%; or from about 0.4 to about 0.6, to about 0.8, to about 1 wt %; or from about 0,6 to about 0.8, to about 1.0 wt %; or from about 0.8 to about 1 wt %, based on the total weight of ingredients being used.[ 0066 i In other situations, solvent can be added in amounts within a range of from about 0 to about 10 wt %, such as within a range of form about 0 to about 2, to about 4, to about 6 to about 8 wt %; or from about 2 to about 4, to about 6, to about 8, to about 10 wt %, or from about 4 to about 6, to about 8 to about 10 wt %; or from about 6 to about 8, to about 10 wt %; or from about 8 to about 10 w4 %.[ 0067 J If used, the solvent can be removed by standard drying techniques. It is expected that the low' solvent levels utilized can be removed completely or nearly so.[ 0068 J Finished products, e.g., films or films laminated onto a current collector, prepared by the solvent-free or dry process described herein can be recognized by the absence of detectable processing solvents or processing solvent residues. In contrast to these “dry” products, products obtained by wet (slurry) techniques will typically include detectable processing solvents and / or processing solvent residues. In a different approach, dry electrodes or films prepared according to embodiments of the disclosure are expected to display a uniform or substantially uniform binder distribution across the electrode or film thickness; in general, less uniformity is observed with wet techniques, which often lead to binder migrations towards a film surface.[ 0069 As for the constituents employ ed, the solvent-free process descri bed herein involves: an electroactive component (a material or combination of materials that participates in the electrochemical charge / discharge reactions of an electrochemical cell such as byDocket: 2022622PCTabsorbing or desorbing lithium); a binder, which can be a fibrillizable or a non-fibrillizable binder; and a carbon additive component. Aspects of the disclosure relate to a carbon additive component that consists of, consists essentially of, or comprises carbon nanotubes (CNTs) and a polymer, in a CNTs-polymer composite, for example.[ o 070 i As known in the art, carbon nanotubes are carbonaceous materials, typically hydrophobic, characterized by at least one sheet of sp2-hybridized carbon atoms bonded to each other to form a honey-comb lattice that forms a cylindrical or tubular structure. The carbon atoms in a carbon nanotube are arranged in a hollow (e.g., cylindrical) structure, having a length that generally is greater than the radial diameter.

[0071] CNTs may have different morphologies, including single-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs). SWCNTs can be thought of as an allotrope of sp2-hybridized carbon similar to fullerenes. The structure is a cylindrical tube including six-membered carbon rings. Double walled carbon nanotubes (DWCNTs) tend to have properties similar to SWCNTs. Analogous MWCNTs, on the other hand, have several tubes in concentric cylinders. The number of these concentric walls may vary, e.g., from 2 to 25 or more. Typically, the diameter of MWNTs may be 10 nm or more, in comparison to 0.7 to 2.0 nm for typical SWCNTs.[ 007'2 J Based on chirality, CNTs are classified into armchair, zigzag and chiral nanotubes.[ 0073 i CNTs can provide excellent electrical and thermal conductivity, and good mechanical properties. With their great conductivity, carbon nanotubes are increasingly adopted as a conductive additive in lithium-ion battery' electrodes. They can enhance battery performance such as power, cycle life and energy density.[ 0074 i In some of the fabrication processes described herein, the CNTs provide multiple benefits (a feature referred to herein as “multifunctional”), serving, for instance, as binder fibrillating (or, in some cases, binder deforming) agents, as conductive additives (generating conductive networks, e.g., the long-range conductivity of the electrode), and as mechanical strengthening aids (imparting mechanical support, stability and / or flexibility to the electrode product, often the coating, layer or film typically applied onto the conductive substrate to formDocket: 2022622PCTa battery electrode). In many cases, these multiple benefits can be realized by supplementing or entirely replacing conventional fibrillating agents (AC, for example) with CNTs.[ 0075 i Both single and multiple walled CNTs can be used, as can mixtures of two or more different types of CNTs. The number of walls present if MWCNTs are employed, determined, for example, by transmission electron microscopy (TEM), at a magnification sufficient for analyzing the number of wall in a particular case, can be within the range of from about 2 to about 30, for example: 4 to 30; 6 to 30; 8 to 30; 10 to 30; 12 to 30; 14 to 30; 16 to 30; 18 to 30; 20 to 30; 22 to 30; 24 to 30; 26 to 30; 28 to 30; or 2 to 28; 4 to 28; 6 to 28; 8 to 28; 10 to 28; 12 to 28; 14 to 28; 16 to 28; 18 to 28; 20 to 28; 22 to 28; 24 to 28; 26 to 28; or 2 to 26; 4 to 26; 6 to 26; 8 to 26; 10 to 26; 12 to 26; 14 to 26; 16 to 26; 18 to 26; 20 to 26; 22 to 26; 24 to 26; or 2 to 24; 4 to 24; 6 to 24; 8 to 24; 10 to 24; 12 to 24; 14 to 24; 16 to 24; 18 to 24, 20 to 24; 22 to 24; or 2 to 22, 4 to 22, 6 to 22, 8 to 22; 10 to 22; 12 to 22; 14 to 22; 16 to 22; 18 to 22; 20 to 22; or 2 to 20; 4 to 20; 6 to 20; 8 to 20; 10 to 20; 12 to 20, 14 to 20, 16 to 20, 18 to 20; or 2 to 18; 4 to 18, 6 to 18, 8 to 18, 10 to 18; 12 to 18; 14 to 18; 16 to 18; or 2 to 16; 4 to 16; 6 to 16; 8 to 16; 10 to 16, 12 to 16, 14 to 16; or 2 to 14; 4 to 14; 6 to 14, 8 to 14, 10 to 14, 12 to 14, or 2 to 12; 4 to 12; 6 to 12; 8 to 12, 10 to 12, or 2 to 10; 4 to 10; 6 to 10; 8 to 10; or 2 to 8; 4 to 8; 6 to 8; or 2 to 6, 4-6; or 2 to 4.[ 0076 J In many implementations, the CNTs employed are conventional (also referred to as “ordinary”, “pristine” or “fresh”) CNTs, which often are provided in individualized form, as manufactured commercially, or, in some cases, as custom-synthesized or processed.[ 0077 i Generally, CNTs are known to contain fair amounts of catalyst and support residuals. These species can be detected by techniques such as SEM, TEM, inductively coupled plasma atomic emission spectroscopy or ICP-AES, etc.

[0078] The CNTs can have a diameter of 100 nanometers (nm) or less, such as, for example, within the range of from about 1 to about 100 nm, e.g., within the range of from about 5 to about: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 nm; or from about 10 to about: 20, 30, 40, 50, 60, 70, 80, 90, 100nm; or form about 20 to about: 30, 40, 50, 60, 70, 80, 90, 100 nm; or from about 30 to about: 40, 50, 60, 70, 80, 90, 100 nm; or from about 40 to about: 50, 60, 70, 80, 90, 100 nm; or from about 50 to about: 60, 70, 80, 90, 10 nm; or from about 60 to about:Docket: 2022622PCT70, 80, 90, 100 nm; of from about 70 to about: 80, 90, 100 nm: or from about 80 to about 90, 100 nm; or from about 90 to about 100 nm.

[0079] Specific embodiments employ CNTs having a diameter within a range of from about 2 nm to about 50 nm, determined by TEM. For instance, the CNTs employed can have a diameter within a range of from about 2 to about: 5, 10, 20, 30, 40 nm; or from about 5 to about: 10, 20, 30, 40, 50 nm; or from about 20 to about: 30, 40, 50 nm; or from about 30 to about: 40, 50 nm; or from about 40 to about 50 nm. In one example, the CNTs have a diameter within a range from about 5 to about 25 nm.[ o o 8 o i CNTs can vary in length from about 10 nanometers (nm) to about 750 microns (am), or higher. Thus, the CNTs can be from 10 nm to 100 nm, from 10 nm to 500 nm; from 10 nm to 750 nm; from 10 nm to 1 micron; from 10 nm to 1.25 micron; from 10 nm to 1.5 micron; from 10 nm to 1.75 micron; from 10 nm to 2 micron; or from 100 nm to 500 nm, from 100 nm to 750 nm, from 100 nm to 1 micron; from 100 to 1.25 micron; from 100 to 1.5 micron; from 100 to 1.75 micron from 100 to 2 microns; from 500 nm to 750 nm, from 500 nm to 1 micron; from 500 nm to 1 micron; from 500 nm to 1.25 micron; from 500 nm to 1.5 micron; from 500 nm to 1.75 micron; from 500 nm to 2 micron; from 750 nm to 1 micron; from 750 nm to 1.25 micron; from 750 nm to 1.5 micron; from 750 nm to 1.75 microns; from 750 nm to 2 microns; from 1 micron to 1.25 micron; from 1.0 micron to 1.5 micron; from 1 micron to 1.75 micron; from 1 micron to 2 microns, or from 1.25 micron to 1.5 micron; from 1.25 micron to 1.75 micron; from 1 micron to 2 microns; or from 1.5 to 1.75 micron; from 1.5 to 2 micron; or from 1.75 to 2 microns.

[0081] In some cases, the CNTs employed in the dry process described herein have an average length within a range of from about 1 microns to about 30 microns, such as within a range of from about 1 to about 5, from about 1 to about 10, from about 1 to about 15, from about 1 to about 20, from about 1 to about 25 microns; or from about 5 to about 10, from about 5 to about 15, from about 5 to about 20, from about 5 to about 25, from about 5 to about 30 microns; or from about 10 to about 15, from about 10 to about 20, from about 10 to about 25, from about 10 to about 30 microns; or from about 15 to about 20, from about 15 to about 25, from bout 15 to about 30 microns; or from about 20 to about 25, from about 20 to about 30 microns; or from about 25 to about 30 microns.Docket: 2022622PCT[ 0082 i In some embodiments, at least one of the CNTs has a length that is equal to or greater than 2 microns, as determined by SEM. In specific embodiments, more than one, e.g., a portion such as a fraction of at least about 0,1%, at least about 1%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50% or even more than one half, of the CNTs, as determined by SEM, can have a length greater than 2 microns, e.g., within ranges specified above,

[0083] The morphology of CNTs will often be characterized by a high aspect ratio, with lengths typically more than 100 times the diameter, and in certain cases much higher.

[0084] CNTs also can be characterized by their surface area. Small-diameter single- wall CNTs, for example, can have specific surface areas up to approximately 3000 m2 / g, such as, for instance, up to about 1315 m2 / g, while large-diameter multi- wall CNTs often are characterized by specific surface areas of up to about 1000 m2 / g.

[0085] In many of the embodiments described herein, the CNTs employed have a Brunauer-Emmett-Teller (BET) surface area, measured, for example, according to ASTM D6556-10, that is less than about 500 m2 / g, such as, for example, less than or equal to 400 m2 / g, or less than or equal to 300 m2 / g.[ 0086 J In some implementations, the CNTs have a BET surface area of from about 80 to about 110, from about 80 to about 200, from about 80 to about 230, from about 80 to about 260, from about 80 to about 280, from about 80 to about 310, from about 80 to about 350 m2 / g, or from about 110 to about 200, from about 110 to about 230, from about 110 to about 260, from about 110 to about 280, from about 110 to about 310, from about 110 to about 350 m2 / g, or from about 230 to about 260, from about 230 to about 280, from about 230 to about 310, from about 230 to about 350 m2 / g; or from about 260 to about 280, from about 260 to about 310, from about 260 to about 350 m2 / g; or from about 280 to about 310, from about 280 to about 350 m2 / g; or from about 310 to about 360 m2 / g.[ 0087 i In some implementations, the BET surface area of the CNTs is within a range of from about 80 to about 500, e.g., within a range of from 200 to about 500 m2 / g. In specific examples, the CNTs have a BET surface area within a range of from about 200 to about: 250,Docket: 2022622PCT300, 350. 400, 450, 500 m2 / g; or from about 250 to about: 300, 350, 400, 450, 500 m2 / g: of from about 300 to about: 350, 400, 450, 500 m2 / g; or from about 350 to about: 400, 450, 500 m2 / g; or from about 400 to about: 450, 500 m2 / g; or from about 450 to about 500 m2 / g. In one example, the CNTs employed have a BET within a range from about 190 to about 280 m2 / g.[ o o 88 i The CNTs can have a bulk density, calculated, for example, as a weight of CNT powder, free-fallen and untapped in the cylinder, divided by volume that the powder occupies, within a range of from about 0.01 to about 0.3, e.g., from about 0.01 to about 0.2, such as about 0.03 g / cm3. Further consolidation, compacting or densification, measured by tapped density, can raise the bulk density to a range between about 0.03 g / cm3to about 0.5 g / cm3.

[0089] The CNTs used herein can be identified and / or characterized by various techniques. Electron microscopy, including techniques such as transmission electron microscopy (TEM) and scanning electron microscopy (SEM), for example, can provide information about features such as the frequency of specific number of walls present, tube diameter, length, branching, the presence of catalyst particles, etc.[ o o 9 o i Raman spectroscopy is often used to characterize the state of carbon in the carbonaceous materials. For example, a D-band (around 1350 cm-1) is associated with sp3- carbon, whereas a G band (around 1580 cm-1) is associated with the sp2- carbon in the graphite or CNTs. A G' band (around 2700 cm-1) is expected to occur at about 2X the frequency of the D band. In some cases, it may be possible to discriminate between the CNTs employed to practice the disclosure and other carbon structures by thermogravimetric analysis (TGA).[ 0091 J Other CNT properties to be considered in multifunctional CNT candidates relate to their physical form. The CNT particle size, for example, is a property that can be determined by particle size distribution (PSD) techniques and / or scanning electrode microscopy (SEM). For example, a particle size analyzer can be used to measure the intensity of scattered light by laser diffraction to conduct particle size measurement. Average particle size (Dso) is the particle size range based on 50% in the particle size distribution of the dispersion. In specific examples, the CNTs have a Dso not greater than about 30, often not greater than about 20 or, in many cases, not greater than about 15 microns.Docket: 2022622PCT[ 0092 i Due to strong van der Waals interactions, e.g., along their length, CNTs can easily form aggregates such as bundles, ropes or agglomerates. CNTs may occur as substantially parallel “forests”, in randomly tangled masses (“pillows”) of structured agglomerations, or other kinds of aggregates.[ o o 93 i In some implementations, aggregates are tailored to have sufficient strength to fibrillate the binder, yet fall apart to some extent, generating smaller fragments that can be spread throughout the composition, yielding a uniform CNT distribution.

[0094] In many embodiments, the CNT-material has a 97% or higher CNT purity.Typically, anionic, cationic or metal impurities are low, e.g., in the parts per million (ppm) range. Often, the CNTs employed herein require no further additives to counteract Van der Waals’ forces.

[0095] Commercially available CNT materials that can be utilized include but are not limited to those available from Cabot Corporation under the tradename of ENERMAX® carbon nanotubes, from CNano under the FT trade name, from LG Chem under the Lucan trade name.[ 00961 The CNTs used in the CNTs-polymer composites described herein can undergo additional processing or modifications. CNT pellets, for example, can be produced by powder compression or by mixing a CNT powder with a liquid, typically water, followed by oven drying.[ 0097 J In some embodiments, the processing step or modification enhances the multifunctional character of the CNTs. In one approach, the CNT material is pre-milled, using, for instance, a high shear mixing apparatus such as, for instance, jet mills, ball mills, extruders, homogenizers, etc. In Table 1 below, CNT3 is a pre-milled version of CNT2. [ 0098 J Typically, pre-milling is conducted before the CNTs are mixed with the fibrillizable binder and / or electrode active material, and often before preparing the CNTs-polymer composite. The pre-milling can be conducted in a dry process, the CNTs being pre¬ milled as a dry powder. In some situations, however, the pre-milling operation can involve a solvent, If this is the case, the solvent can be removed by heat drying, freeze drying, or vacuum.Docket: 2022622PCT[ o o 99 i A pre- milling operation, optionally in conjunction with a drying step (if solvent is employed), can increase the electrochemical performance and may enhance the fibrillizing potential of the CNTs. Pre-milling may also bring about positive mechanical effects in the film and / or electrode product. Without wishing to be bound to a particular interpretation, it is believed that the smaller particles in the pre-milled (also referred to herein as “pulverized”) material can be more uniformly dispersed through the composition, thereby enhancing electrical and mechanical properties of the product (film or electrode).[ o o 1 o o j An illustrative CNTs-polymer composite contains pulverized CNTs having a Dso not greater than about 15 microns.[ ooioi] In another approach, the CNTs employed in the CNTs-polymer composite entirely lack or have reduced numbers of oxygen- containing surface groups. The reduction or absence of oxygen containing groups such as -OH, -O-, -COOH, etc., increases the hydrophobic character of the additive and thus increases the affinity of the CNTs to a hydrophobic polymer or fibril lizable binder such as PTFE. One technique for removing oxygen-containing groups from CNTs is heat treatment, which can be conducted in a vacuum oven, for example.[00102 J In addition to enhancing the hydrophobic character of the CNTs, heat treatment can also improve their electrical conductivity and reduce or minimize impurities (such those left behind from the manufacture of the CNTs) that can interfere and negatively impact cyclic performance, hot storage and / or battery safety. Other techniques that can be employed to remove impurities, include, for instance, acid washing, a combination of heat treatment and acid washing, or other techniques. In some approaches, the acid treatment includes oxidation with HNO₃,, H2SO4, HC1, HF, alone or in any combinations thereof, or graphitization. Other possible approaches include wetting MWCNTs with dimethyl formamide (DMF), oxidized first, then suspended in nitric acid.[ 001031 CNTs can be doped (with boron, for example), graphene-winged or otherwise treated.[ 001041 More than one process and / or modification can be undertaken. For example, CNTs may be both heat-treated and pre-milled.Docket: 2022622PCT[ 00105 i Thus, in general, the CNTs-polymer composite described herein can utilize CNTs without any further processing or modification (e.g., not comminuted (e.g., not pulverized), not heat-treated, not acid- washed, etc.), pulverized (pre-milled) powders, modified, e.g., heat treated CNTs, acid washed CNTs, and so forth. TEM, X-ray tomography or other techniques could be used to determine the type of CNTs employed, in some cases. Good multifunctional properties often are reflected in the quality' of the film, electrode or battery product obtained.

[0106] Blends of two or more CNTs can be utilized in some cases. For instance, CNTs can form or be compounded to form mixtures of CNTs with various combinations and distributions of the above characteristics (number of walls, diameters, lengths, morphologies, orientations, etc,).[ 00107 i Table 1 below presents physical properties characterizing illustrative CNTs, namely CNT1 through CNT10.Table 1Bulk PSD CNT type BET, m2 / g Diameter, density, (pm) nm g / cm3Dso CNT 1 208.41 | 10-20 0.06 <15 CNT 2 265.6 i 9-12 0.12 133-135 CNT 3 261.6 i 9-12 0.0308 15 CNT 4 / 9-12 / <15 CNT 5 300.41 | 5-10 0.092 60 CNT 6 225.59 j 10-20 0.16 55 CNT 7 101.22 i 30-50 0.149 80 CNT 8 268.8 i 5-10 0.0189 15-16 CNT 9 229.7 10-20 0.0614 11-15CNT 10 91.2 j 30-50 0.0511 9-15

[0108] Some embodiments employ CNTs in combination with another material, one or more types of carbon black (CB), for example. In specific implementations, the CB is multifunctional, as described, for instance, in U. S. Provisional Patent Application No.63 / 322,074, file / d on March 21, 2022, and in International Patent Application No.PCT / US23 / 64614, filed on March 17, 2023, published as WO2023 / 183754 Al on SeptemberDocket: 2022622PCT28, 2023), both with the title Solvent-Free Process for Preparing Lithium -Ion Batteries and both being incorporated herein by this reference.

[0109] The CNTs also can be provided in combination with a polymeric material. In many aspects of the disclosure, the CNTs are a constituent in a CNTs-polymer composite. The polymer in the CNTs-polymer composites described herein serves as a glue, connecting, binding together and providing connectivity for CNTs, mitigating health and safety concerns related to the potential release of airborne particulates that may arise in the context of solvent- free manufacture. The presence of polymer in the CNTs-polymer composite can further help facilitate the incorporation of CNTs into electrode compositions by interacting with the binder polymer, facilitating mixing, and easing CNT-polymer composite dispersibility,[ oo 110 i For many applications, the polymer employed in the CNTs-polymer composite is a per- and polyfluoroalkyl substance (PF AS), such as polytetrafluoroethylene (PTFE). In other cases, the CNT-polymer composite contains per- and polyfluoroalkyl substances (PFAS)-free polymers, such as, polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG). Combinations of PF AS and PFAS-free polymers can also be utilized.[ o o 111 J Further examples of polymeric constituents that can be employed include but are not limited to other fluorinated polymers such as poly(vinyldifluoroethylene) (PVDF), poly(vinyldifluoroethylene-co-hexafluoropropylene) (PVDF-HFP), polyimides, and water- soluble binders, such as poly(ethylene) oxide, polyvinyl-alcohol (PVA), cellulose, carboxymethylcellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, and copolymers and mixtures thereof. In some implementations, the CNTs used are treated with a PTFE, PVP, CMC, or with polyethylene glycol (PEG). As with the binders used (further described below), the polymer can be fibrillizable or non-fibrillizable.[00112 i Polymers such as, for instance, epoxy, polyester, viny lester, polyetherimide, polyetherketoneketone, polyphthalamide, polyetherketone, polyetheretherketone, polyimide, phenol-formaldehyde, bismateinnde, acrylonitrile-butadiene styrene (ABS), polycarbonate, polyethyleneimine, polyurethane, a thermoplastic polyurethane, polyvinyl chloride, polystyrene, polyolefins, polypropylenes, polyethylenes, polytetrafluoroethylene, elastomers such as, for example, polyisoprene, poly butadiene, butyl rubber, nitrile rubber, hydrogenatedDocket: 2022622PCTnitrile butadiene rubber (HNBR), ethylene-vinyl acetate polymers, silicone polymers, and fluorosilicone polymers, combinations thereof, or other polymers or polymeric blends can also be used in some cases. In order to enhance electrical conductivity, conductive polymers such as, for instance, polyanilines, polypyrroles, and polythiophenes can also be used.[ 00113 i The polymer loading in the CNTs-polymer composite can be within the range from about 0.1 weight percent (wt %) to about 50 wt % of the composite, e.g., in a range from about 0.1 wt % to about 10 wt %. The polymer amount relative to that of CNTs can be further refined to mitigate safety concerns or to address other desired goals. In various embodiments, the concentration of the polymer is expressed as a ratio of the CNT to the dispersant polymer by weight. One illustrative CNTs-polymer composite has a CNT to polymer weight ratio of about 19: 1. In another illustrative CNTs-polymer composite the weight ratio of the CNTs to the polymer is 200: 1. More generally, the weight ratio of the CNTs to the polymer present in the composite is within a range from about 1:1 to about 100:0.1, such as from about 10:1 to about 100:0,1.[ o o 114 i The CNTs-polymer composite described herein can be prepared by various techniques. Once formed, the composite material can be further processed. In some situations, the composite material is oven dried or freeze dried (in view of a subsequent solvent-free fabrication approach). Other possible processing steps include but are not limited to sieving and / or pelletization.[ 00115 J In one implementation, CNTs in powder form are combined with the polymer, also in powder form, using dry mechanical mixing.[ 00116 J In other approaches, one or both ingredients (CNTs and / or polymer) can be provided in a dispersion, often an aqueous dispersion. In addition to water, aqueous dispersions can include one or more dispersants, e.g. PVP-based dispersants, and / or other ingredients. Examples of suitable dispersants include poly(vinyl pyrrolidone), poly(vinylpyrrolidone-co-vinyl acetate), poly(vinyl butyral) (or PVB), poly(vinyl alcohol), poly(ethylene oxide), poly(propylene oxide), poly(propylene carbonate), cellulosic dispersants such as methyl cellulose, carboxymethyl cellulose, ethyl cellulose, hydroxymethyl cellulose and hydroxypropyl cellulose; poly(carboxylic acid) such as poly (acrylic acid), polyacrylate,Page 2.3 of SpecificationDocket: 2022622PCTpoly(methylacrylate), poly(acrylamide), amide wax, styrene maleic anhydride resins, octylphenol ethoxylate, multifunctional co-dispersants such as AMP™ dispersants, containing 2-amino-2-methyl-l- propanol, various derivatives and others known in the art. The compositions can include one or more than one dispersant(s) or one or more than one dispersant formulation(s). In many cases, aqueous dispersions will contain water in an amount of at least 40 wt %, typically in an amount of at least 75, 90 or 95 wt %. CNTs dispersions can be prepared by sonication, high shear mixing or other suitable techniques. Polymeric dispersions in various specifications can be obtained commercially or can be custom made by methods known in the art.

[0117] In some embodiments, stable dispersions can be achieved in the absence of stabilizing surfactants (dispersants), even with water as solvent. Suitable examples of solvents that can also be used include, but are not limited to, N-methyl pyrrolidone, acetone, a suitable alcohol (e.g., isopropanol, ethanol, methanol), water or any combination thereof.[ o o 118 J Since the solvent-free fabrication process described herein uses CNT-polymer composites in a loose, free flowing or pourable dry form (e.g., powders, pellets, flakes, granules, etc.), any solvents used in the dispersion) s) are removed by a suitable technique. [ o o 119 i One example for preparing a CNTs-polymer composite involves combining a dispersion containing CNTs with a polymer dispersion (e.g., a PTFE dispersion in water), followed by freeze drying the resulting mixture. Freeze drying of carbon-containing mixtures is described in PCT Application No. PCT / CN2023 / 132882, filed on November 21, 2023, incorporated by reference. In another example, CNTs in dry powder form are mixed with a polymer dispersion, such as a PTFE or a PVP dispersion in water, which results in a paste-like material of high viscosity. This paste can be pelletized (using equipment and techniques known in the art), then dried, e.g., in an oven.[ o 012 o i While various approaches can result in forming CNTs-polymer composites, it was discovered that some may yield a better product. Mixing the same polymer dispersion (PTFE Dispersion 30, for instance) with unpulverized CNTs (Dso of about 133 to 135 microns) and pulverized CNTs (Dso of approximately 15 microns) indicated that it was the smaller CNT particles that produced a smoother, higher quality free standing film. In contrast, the largerPage 2.4 of SpecificationDocket: 2022622PCTCNTs gave rise to a rougher film surface, presenting many undispersed carbon features. Thus, at least in some situations, smaller (e.g., pulverized) CNTs may be preferred when making CNTs-polymer composites from dry CNTs and a polymer dispersion.[001211 It was also discovered that mixing an aqueous CNT dispersion with an aqueous dispersion of PTFE binder, followed by freeze drying, did not appear to improve dispersibility and / or binder fibrillization in at least some dry electrode fabrication processes. In some cases, it was also found that mechanical mixing of dry' CNTs and PTFE powders was inadequate in forming a CNTs-PTFE composite particularly suitable to meet dry' processing needs. In contrast, dry CNTs powders combined with a polymer (e.g., PTFE or PVP) aqueous dispersion, followed by oven drying seemed to yield beter quality film electrodes.[ 00122 i CNTs-polymer composites, optionally sieved, can be formed into pellets by techniques known in the art. In some implementations, the CNTs-polymer pellets have a particle size from about 0.5 to about 30 mm, e.g., from 3 to 15 mm, in either direction. One example has cylindrically shaped CNTs-polymer pellets that are about 4 mm in diameter and about 5-15 mm in length.[ o o 123 J For many sol vent- free manufacturing processes, the CNTs-polymer composite material has reduced dustiness. As used herein a “dust-free” CNTs-polymer composite refers to a material that exhibits weight loss of no greater than 5 wt %, 4wt 3 wt %, 2 wt%, or 1 wt% upon screening through a 20-mesh sieve with 840pm opening.[ 00124 J In addition to the CNTs-polymer composite, the method, composition and / or articles (e.g., film, electrode, battery) described herein also employ a binder. In some embodiments, the binder is a fibrillizable binder. The fibrillizable binder can be provided in a binder component that consists of, consists essentially of, or comprises the fibrillizable binder.[ 00125 J Under certain processing conditions, e.g., high shear mixing in the presence of a fibrillizing agent, a fibrillizable binder is capable of producing fibrils, forming a network that can connect and support other particles present in the formulation. In more detail, it is believed that fibrillization of the binder generates a matrix, lattice, or web of fibrils that imparts mechanical structure to the electrode. In a product electrode, a fibrillized binder can be detected in SEM images which will show the presence of fibrils wrapped around at least aDocket: 2022622PCTportion of at least some of the particles present, e.g., active material particles. Other indirect techniques that can be employed to evaluate relative degree of binder fibrillization include, for instance, energy-dispersive X-ray spectroscopy (EDX), powder rheology, tensile strength, elastic (Young’s) modulus. EDX allows to map fluorine element distribution throughout the dry electrode and evaluate effectiveness of binder fibrillization. Powder rheology measures the cohesive interaction between the particles in the free-flowing electrode powder mix, while tensile strength and elastic modulus testing measures strength and flexibility of the free¬ standing electrode film, all being representative of the degree of binder fibrillization. In some cases, poor or no fibrillization can be inferred for dry product electrode films that crumble or peel away from the substrate.

[0126] In some implementations the fibrillizable binder is a fibrillizable fluoropolymer, such as, for instance, polytetrafluoroethylene or PTFE. Other binders that can be considered fibrillizable include but are not limited to ultra-high molecular weight polypropylene, polyethylene, and co-polymers and any combination thereof.[ 00127 i The fibrillizable binder (alone or as a constituent in a binder component (e.g., in a polymer blend)) can be provided in an amount of about 0.1 to about 10 % by weight, e.g., about 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10 wt %. In one example, the fibrillizable binder is provided in an amount of about 5 wt %. In other examples the fibrillizable binder is provided in an amount within a range from about 0.1 to: about 0.5, about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 0.5 to: about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 1 to: about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 2 to: about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 3 to: about 4, about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 4 to: about 5, about 6, about 7, about 8, about 9, about 10 wt %; or from about 5 to: about 6, about 7, about 8, about 9, about 10; or from about 6 to: about 7, about 8, about 9, about 10 v %; or from about 7 to: about 8, about 9, about 10 v %; or from about 8 to: about 9, about 10 wt %.

[0128] Not all situations, however, will employ a binder that is fibrillizable. Thus, some embodiments of the disclosure employ a binder component that consists of, consistsDocket: 2022622PCTessentially of, or comprises one or more non-fibrillizable binders. As used herein, the term “non-fibrillizable” binder refers to a binder that is difficult to fibril lize at the same conditions that are sufficient to fibrillate a “fibrillizabl e” binder. Nevertheless, even without reaching full fibrill ization, practicing aspects of the disclosure (at the same or substantially the same processing conditions used for a fibrillizable counterpart) can still deform, e.g,, stretch out, elongate, entangle, etc. a non-fibrillizable binder, often to a significant extent.[ o o 129 i Without wishing to be bound by a particular interpretation or mechanism, it is believed that fibrillization may be thought of as an extreme phenomenon, where the binder polymer (which may start out as a colloidal particle) becomes stretched out very thinly, forming very long (high aspect ratio) strands (ribbons) that can bridge across more than two electroactive particles, thereby holding them together. Practicing embodiments described herein also can lead to stretching (elongating) and / or entangling a non-fibrillizable binder, forming CNTs-binder composites and / or becoming coated with CNTs. Even if not fully fibrillated, such a “processed” non-fibrillizable binder can still serve as a glue, connecting, binding together and providing connectivity for the electroactive particles and adhesion to the current collector. Deformations of a non-fibrillizable binder can be observed by at least some of the techniques noted above.[ 00130 J In one example, the non-fibrillizable binder is a fluoropolymer such aspoly vinylidene fluoride (PVDF). Other examples of binders that can be considered non- fibrillizable include poly(vinyldifluoroethylene-co-hexafluoropropylene) (PVDF-HFP), poly imides, and water-soluble binders, such as poly(ethylene) oxide, polyvinyl-alcohol (PVA), polyvinyl pyrrolidone (PVP), polyvinyl acetate, polyethylene-co-vinyl acetate, some poly olefins, cellulose, cellulose derivatives, to name a few. Other possible non-fibrillizable binders include polyethylene and polypropylene other than ultra-high molecular weight, ethyl ene-propy lene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber (SBR), butyl rubber, nitrile rubber, acrylonitrile-butadiene rubber (NBR) and its derivatives, e.g. hydrogenated nitrile butadiene rubber (HNBR), and fluoro rubber, and copolymers and mixtures thereof. In one example, the non-fibrillizable binder is a cellulose ester, a cellulose ether, cellulose nitrate, a carboxyalkylcellulose, a cellulose salt and a cellulose salt derivative. In some embodiments, the microparticulate non-fibrillizable binder is selected from at leastDocket: 2022622PCTone of cellulose, cellulose acetate, methylcellulose, ethylcellulose, hydroxylpropylcellulose (HPC), hydroxy ethylcellulose (HEC), cellulose nitrate, carboxymethylcellulose (CMC), carboxyethylcellulose, carboxypropylcellulose, carboxyisopropylcellulose, sodium cellulose, sodium cellulose nitrate, and sodium carboxyalkylcellulose. Other examples employ combinations of a non-fibrillizable binder, PVDF, for instance, and fibrillizable binder, PTFE, for instance.[ o o 131 1 Non-fibri Uizable binders can be present in the electrode compositi on in the same amounts as those used for fibrillizable binders. Other suitable amounts can be employed, as determined by routine experimentation, for example.[ 001321 Fibrillizable binders in combination with non-fibrillizable binders also can be employed. Routine experimentation can be used to arrive at suitable amounts. In many cases, the total amount of the combined binders is the same or similar to the amounts described for fibrillizable binders.

[0133] The binder employed can be the same as or different from the polymer in the CNTs-polymer composite. One example utilizes a PTFE binder and a CNTs-PTFE composite. Selecting composite formulations in which the polymer is the same as or compatible with the binder can enhance the binder affinity to the CNT / polymer composite particle and, subsequently, improve distribution, elongation and / or fibrillization of polymeric binder, ease dispersibility of CNT / polymer composite, promote uniform distribution of electrode constituents for better adhesion within the electrode and / or to a conductive substrate (current collector). As used herein, the term “compatible” refers to compounds that can be mixed together, do not undergo decomposition or chemical property changes, and have desirable physical properties upon mixing.

[0134] In some cases, the binder can be supplied partially or entirely via the CNTs- polymer composite.

[0135] For many LIB anodes, the electroactive material (also simply referred to herein as “active material” or “AM”) is graphite, e.g., natural graphite, artificial graphite (e.g., massive artificial graphite (MAG)) or blends of both. Mesocarbon microbead (MCMB), mesophase-pitch-based carbon fiber (MCF), vapor grown carbon fibre (VGCF) also can be employed.Page 2.8 of SpecificationDocket: 2022622PCTOther anode materials used in addition to or alternatively to graphite include lithium titanate, tin oxide, silicon (Si) and SiOx (with x typically being 1,04, 1.06, etc.). In illustrative examples the anode includes graphite and / or a sili con-containing compound. Other active anode materials such as, for instance, those known or currently explored, or those to be developed in the future, can be employed.

[0136] The amount of the active anode material can vary, depending on the particular type of energy storage device. In illustrative examples, the amount of active anode material (graphite, for instance) is at least 80 % by weight, e.g., at least 85, at least 90, at least 95, or at least 99 wt %, relative to the total weight of the (dry) electrode composition. The anode active material, e.g., graphite, can be provided in an amount of from about 80 to about: 85, 90, 93, 96, 99 wt %; or from about 85 to about: 90, 93, 96, 99 wt %; or from about 90 to about: 93, 96, 99 wt %; or from about 93 to about: 96, 99 wt %; or from about 96 to about 99 wt%.[ 00137 i LIBs cathodes can employ LCO (lithium cobalt oxide), LMO (lithium manganese oxide), NCM (lithium nickel cobalt manganese oxide), NCA (lithium nickel cobalt aluminum oxide), LCP (lithium cobalt phosphate), LFP (lithium iron phosphate), LFMP (lithium iron manganese phosphate), LFSF (lithium iron fluorosulfate), LTS (lithium titanium sulfide). Materials such as these are generally referred to herein as “lithium transition metal compounds”, e.g., “lithium transition metal oxides”. In addition to cathode materials based on intercalation chemistry, e.g., typically involving chemical reactions that transfer a single electron, other types of cathode materials (having lithium ions inserted into FeFs, for instance) can transfer multiple electrons through more complex reaction mechanisms, called conversion reactions. Other active cathode materials known in the art or developed in the future can be employed.

[0138] In some embodiments, the dry process described herein utilizes NCM or NCA cathode compositions. NCM (also referred to as “NMC”) and NCA are generally known to those skilled in the art.[ 00139 i In more detail, NCM can be represented by the formula Li1+x(NiyCo1-y-zMnz)1-xO2, wherein x ranges from 0 to I, y ranges from 0 to I (e.g., 0.3-0.8), and z ranges from 0 to 1 (e.g., 0.1-0.3). Examples of NCMs include Li1+x(Ni0.33Co0.33Mn0.33)1-xO2,Page 2.9 of SpecificationDocket: 2022622PCTLi1+x(Ni0.4Co0.3Mn0.3)1-xO2, Li1+x(Ni0.4Co0.2Mn0.4)1-xO2, Li1+x(Ni0.4Co0.1Mn0.5)1-xO2, Li1+x(Ni0.5Co0.1Mn0.4)1-xO2, Lll+x(N10.5CO0.3 4n0.2)l"XO2, Li1+x(Ni0.5Co0.2Mn0.3)1-xO2,Li1+x(Ni0.6Co0.2Mn0.2)1-xO2, Li1+x(Ni0.8Co0.1Mn0.1)1-xO2a nd! ’■ l-rx N iu.9C0.03 4n0.03) l~xO2.[ 001401 NCA can be represented by the formula Li1+x(NiyCo1-y-zAlz)1-xO2, wherein x ranges from 0 to 1, y ranges from 0 to 1, and z ranges from 0 to 1, An example of an NCA is Li1+x(Ni0.8Co0.15Al0.05)1-xO2.[ o o 141 1 The amount of electroactive cathode material employed can vary, depending on the particular type of energy storage device. In illustrative examples, the amount of NCM or NCA is at least 90% by weight, e.g., at least 93%, at least 96, at least 98, or at least 99 % by weight, relative to the total weight of the (dry) electrode composition. NCM or NCA can be provided in an amount of from about 90 to about: 93, 96, 99 wt %; or from about 93 to about: 96, 99 wt %; or from about 96 to about 99 wt%.[ 00142 i Electrode compositions routinely include ingredients such as conductive additives (e.g., conductive carbon additives or CCA), plasticizers and so forth. In the case of solvent- free processes, common techniques also call for a binder fibnllizing (also known as “fibrillating”) agent or aid, typically AC.[ 00143 i It was discovered that conventional fibrillizing additives (AC, for example) can be supplemented and often entirely replaced when using the CNTs-polymer composite described herein. The CNTs in the composite can provide multiple benefits (a feature referred to herein as “multifunctional”), serving, for instance, as binder fibrillating (or, in some cases, binder deforming) agents, as conductive additives (generating conductive networks, e.g., the long- range conductivity of the electrode), and as mechanical strengthening aids (imparting mechanical support, stability and / or flexibility to the electrode product, often the coating, layer or film typically applied onto the conductive substrate to form a battery electrode).

[0144] In many cases, the solvent-free process is conducted in the absence of any fibrillating aids other than the CNTs-polymer composite described above.[ 00145 i It is also possible to utilize the CNTs-polymer composite in combination with a another fibrillizing aid or fibnllizing agent. As used herein, the term “fibrillizing aid” or “fibnllizing agent” refers to a material that is other than the binder or active electrode materialDocket: 2022622PCTand that promotes filbrillization of a fibrillizable binder); “additional” or “other” fibrillizing aid or “additional” or “other” fibrillizing agent refers to a material other than (i.e., a material that excludes or is not) the CNTs in the CNTs-polymer composite. Typically, the additional fibrill izati on aid is not considered multifunctional. In some applications, the CNTs in the composite are combined with AC, in a ratio that can be within a range of from about 95:5 to about 50:50,[ 001461 Examples of other or additional materials that can be provided along with the CNTs-polymer composite can include a hard carbon, graphite, graphenes, other non- fibrillizing conductive additives, plasticizers, or any combination thereof.

[0147] Shown in FIGS. 1 A through ID is a schematic diagram and corresponding photographs of steps typically involved in a preparation procedure starting with CNTs- polymer composite to the free-standing film. In more detail, the CNTs-polymer composite of FIG. 1 A is sequentially mixed with an electrode active material and a binder to form an intermediate (FIG. IB) that is subjected to binder deformation (FIG. 1 C), then formed into a film (FIG. ID).[ 00148 J Ingredients such as the electroactive material, the binder and the CNTs-polymer composite described above can be used as loose particulate materials (e.g., flowing or pourable powders, flakes, beads, granules, pellets) to prepare an electrode composition, an electrode product (e.g., a film, such as a free-standing film), an electrode (in which the electrode composition or the electrode product (film, for example) has been applied onto a conductive substrate), and / or batteries. In some cases, the CNTs-polymer composite is provided in a sponge- like structure.[ 00149 i Turning first to the dry process employed to prepare the electrode composition, performing this process targets at least two objectives: blending some and typically all the constituents, typically provided in the form of loose (e.g., flowing or pourable) particles; and processing the binder in the presence of the CNTs in the CNTs-polymer composite. In some embodiments, each of these two objectives is met by one or more mixing operations conducted under specific shear conditions, using suitable equipment.Docket: 2022622PCT[ 00150: A low shear mixing, for example, can be selected to distribute ingredients, as uniformly as possible, for example utilizing a roll mill. As used herein, the term “low shear mixing” refers to mixing conducted under conditions that are not sufficient or not substantially sufficient to fibrillize a fibri Uizable binder. Relying on low shear mixing conditions also can avoid excessive particle fragmentations, often a consideration for some electroactive materials.[ 001511 In many embodiments, processing the binder is conducted under high shear mixing. As used herein, the term “high shear mixing” refers to shear conditions that are vigorous enough to deform (e.g., elongate, entangle) a binder to a degree sufficient to prepare a film electrode by a solvent-free technique. In the case of fibrillizable binders, high shear mixing refers to mixing under shear conditions that are sufficient to fibrillize the binder.[ 00152 i Without wishing to be bound by a particular interpretation, it is believed that, in the presence of CNTs, typically supplied in a CNTs-polymer composite, and under high shear conditions, a binder polymer is deformed, becoming stretched out, elongated and entangled. Providing CNTs in a CNTs-polymer composite can ease dispersibility of CNT aggregates, enhance the CNT distribution throughout the mixture for higher electrode conductivity and cell performance, reinforce larger polymer domains and polymer fibrils for improved electrode processability, strength and flexibility, and / or other benefits. Surface energy, elongated tubular shape, and / or the surface roughness atributes can facilitate grabbing hold of the binder polymer; the CNTs can become squished between electroactive particles, resulting in the binder polymer being stretched out. With CNTs-polymer composite dispersed in the binder or on the surface of the binder, it is thought that the CNT particles can hold together neighboring polymer domains. Other contributing factors include polymer-polymer interactions (which are expected to increase with increased polymer elongations and / or with multi-directional shear forces), electroactive particles-polymer binder interactions (which can relate to surface energy, and / or other factors.[ 00153: At the same or substantially the same high shear conditions, these manifestations tend to become more pronounced when the binder employed is a fibrillizable binder. Surface and other properties of the CNTs can promote snagging the polymer here and there. With all particles moving under high shear mixing, the polymeric binder and the polymer in the CNTs- polymer composite becomes elongated, forming very long, very thin strands (having a highDocket: 2022622PCTaspect ratio). In some cases, elongation can be observed only for the binder. Typically, these effects will be less pronounced with a non-fibrillizable binder processed at the same or substantially the same high shear conditions. Or, stated differently, a non-fibrillizable binder may require increased high shear conditions to obtain results approaching full fibril lization.[ 00154 i In addition to the processing contributions described above, CNTs in the CNTs- polymer composite can enhance electrical conductivity and, in many cases, can act as a mechanical reinforcement by holding together fibri llizable as well as non-fibrillizable polymer binders that are “deformed” (elongated, entangled, etc.) to a full or lesser extent or “undeformed” (globular, rounded, spherical shaped, etc.).

[0155] Specific shear values can depend on the scale of the operation, the materials involved, type of mixing equipment and / or other factors. Low or high mixing settings can be determined or optimized based on prior experience, routine experimentation, and so forth.

[0156] Constituents can be combined in any order designed to obtain a mixture, preferably one that is well dispersed, e.g., with a uniform distribution of the constituents, in other words a mixture that is homogeneous. In one example, the CNTs-polymer composite, in pellet form, for instance, is homogeneously dispersed on the surface of the electroactive material and the binder. If CB is employed, it can be mixed with the CNTs-polymer composite to form a pre¬ blend. In a different approach, CNTs-polymer composite and CB can be added individually to one or more other ingredients. This addition can be simultaneous or sequential.[ 00157 J Binder processing (e.g., fi brill ization) can be performed on any mixture or pre¬ mixture (pre-blend) which brings together CNTs and the binder. In some implementations, the polymer in the CNTs-polymer composite is processed, e.g., fibrillized, along with the binder. [ o o 158] Suitable techniques that can be used or adapted to conduct the steps of mixing and / or binder processing, e.g., fibril! ization, include mechanical agitation, shaking, stirring, etc., and can rely on equipment such as jet mills, tube mills, acoustic mixers, extruders, planetary mixers, other mixing devices, e.g., laboratory-scale mixers, equipment suitable for pilot-scale evaluations, for full-scale industrial manufacturing and so forth.Docket: 2022622PCT[ 00159 i Stepwise sequences can employ one type of apparatus to conduct the first operation (e.g., preparing a pre-blend), and another type of apparatus in the subsequent operation (fibril lizati on, for instance). The same is true for shear and / or other mixing parameters.

[0160] In one embodiment, the CNTs-polymer composite, e.g., in pellet form, is first pre-processed using high shear equipment to break the composite and multifunctional additive particles (pelletized granules or other particulates susceptible to comminution under high shear conditions) into smaller fragments. The resulting mixture is then combined with the electroactive material, followed by addition of the binder; use of low' shear conditions during these steps favors preserving particle size (of the electroactive material, for example) and good mixing of all constituents without fibrillizing the binder. The electrochemical active material, the binder and the CNTs-polymer composite mixture is then subjected to high shear conditions to process, e.g., fibrillate, the binder.[ 00161: In another embodiment, CNTs-polymer composite, in pellet form, for instance, is first combined with the electroactive material in a pre-mixing step conducted under low' shear, for example, to obtain a uniform distribution of these two constituents. The binder is then added to this pre-blend and processed, e.g., mixed with other constituents without being fibnllized, under low shear conditions. The mixture is then subjected to high shear conditions to process, e.g., fibrillate, the binder.[ 00162 i Other sequences are possible. For instance, the electroactive material can be first mixed with the binder, followed by the addition of the CNTs-polymer composite, e.g., in the form of pellets, followed by binder processing, e.g., fibnllization, under high shear conditions.[ 00163 J Low shear mixing and / or processing (fibnllization, for example) can be conducted in one or more (two, three, four, five, six, etc.) mixing stages or pulses(s) that can last for a suitable period, e.g., withing a range of from about 10 seconds to about 5 minutes, e.g., within a range of from about 30 seconds to about a minute, to about 90 seconds, to about 2 minutes, to about 2.5 minutes, to about 3 minutes, to about 4 minutes, to about 5 minutes; from about 1 minute to about 90 seconds, to about 2 minutes, to about 3 minutes, to about 4 minutes, to about 5 minutes; From about 90 seconds to about 3 minutes, to about 4 minute, to about 5 minutes; from about 2 minutes to about 3 minutes, to about 4 minutes, to about 5 minutes;Docket: 2022622PCTfrom about 3 minutes to about 4 minutes, to about 5 minutes; from about 4 minutes to about 5 minutes. Different time intervals also can be employed. The duration of two, more or all pulses can be the same or different,

[0164] A pulse can be followed by a rest or a cool down period. Resting periods can be at ambient, e.g., room temperature. Cooling can be to a temperature below ambient, e.g., below room temperature, often at 0°C or below, for instance at a temperature within a range of about -5 to about 5°C.

[0165] The rest or cooling period can depend on temperatures reached during mixing, quantities handled, and so forth. In many cases, cooling will last for a few minutes, e.g., 10 minutes to half an hour or longer. Cooling periods can differ in duration and / or temperature conditions,

[0166] To illustrate, a binder-containing composition can be subjected to a high shear blending at about 25,000 RPM to about 10,000 RPM, optionally at about 18,000 RPM for half a minute, then cooled to a temperature at or below freezing, for 10 minutes, e.g., at about - 10°C. A low shear mixing can be conducted at about 2,000 RPM to about 4,000 RPM, for 1 minute followed by a cool down for 10 minutes at about 0°C.[ 00167 i In one example, a pre-blend of CNTs-polymer composite and electroactive material is prepared using an acoustic mixer e.g., for several minutes at. 100 G force. The resulting blend is combined with the binder at fi brill izati on parameters, e.g., using a tube mill (such as an IKA TubeMill 100) at 25,000 rpm in a pulsed approach.[ 00168 i In another example, all components are mixed in a tube mill (such as an IKA TubeMill 100) at 25,000 rpm in a pulsed approach in which blending is alternated with rest, periods, followed by a longer duration mixing operation.

[0169] Other techniques or equipment, a twin-screw extruder, for instance, can be employed.

[0170] CNTs-polymer composite entities, pellets, for instance, can remain intact or can become fragmented under processing conditions. Processing conditions can preserve the integrity of some or all the initial CNTs present in the composite, which will remain intact. In some cases, however, under high shear conditions, for instance, initial CNTs are broken intoDocket: 2022622PCTsmaller CNT units, generating CNT fragments, for example. Except for their reduced sizes, CNT fragments generally share the properties of intact CNTs and can be identified by electron microscopy and other techniques, as described above. Applied shear can distribute these fragments throughout the composition. Without wishing to be bound to a particular interpretation, it is believed that CNTs, as well as comminuted CNTs, distributed, e.g,, uniformly, in the electrode composition, can result in electrodes with enhanced electrical conductivity and / or desirable mechanical properties.

[0171] Mixing and / or processing, e.g., fibrillization, steps can be monitored by visual inspection, hand calendaring, powder rheology, or another suitable technique. For instance, a small amount can be handled manually and sheared or passed through a hand calendar. End points can be established based on experience, routine experimentation, visual inspection, and so forth. Whether these operations have been successful also can be determined by SEM, performance and / or other techniques typically conducted on the electrode product, e.g., an electrode film.[ 00172 i The resulting electrode composition can be in the form of pellets, powders (often fluffy powders), composites such as polymer-encapsulated granules (masterbatch) or other forms of free flowing or loose particulate materials.[ 00173 J In an optional step, the electrode composition can be sieved to remove unwanted clumps.[ 00174 J The electrode compositions prepared as described herein will typically include CNTs, an active electrode material, and a “processed” binder, which, in some cases, will include the processed polymer in the CNTs-polyrner composite. Some product electrode compositions, in particular those prepared with a fibrillizable binder, will include a post fibrillization binder (also referred to herein as a “fibrillized binder”), often exhibiting fibrils of high aspect ratios. Compositions prepared with non fibrillizable binders wall still present a binder that is “deformed” (elongated, entangled, etc.) but perhaps to a lesser extent than that observed with fibrillizable binders at the same or substantially the same fibrillization conditions. A processed, e.g., fibrillized, binder can be detected by techniques described above. Successful binder processing, e.g., fibrillization, often is reflected by the quality of theDocket: 2022622PCTresulting electrode (electrode film, for example). In some cases, electrode compositions prepared with non fibrillizable binders will include a binder that is “undeformed” (globular, rounded, spherical shaped, etc,). Even in such cases, the CNTs can act as a binder and mechanical reinforcement of the electrode.[ oo 175 i The electrode compositions can be employed to form an anode, cathode or both an anode and a cathode, e.g., for assembly in a device such as a LIB. One, more, or all properties characterizing the CNTs-polymer composite employed, can be assessed in the product electrode composition, (in which the binder has been processed, e.g., fibrillized), in product electrodes (e.g., films), typically obtained by further processing the product electrode composition, assembled electrodes (in which the product electrode, e.g., film, has been applied to the suitable substrate) and / or batteries described herein. For example, the electrode can be tested for adhesion (assessing the atachment of the electrode film to a substrate), cohesion (assessing how well particles are bound together), electrode resistivity and / or other properties, by techniques known in the art.[ 001761 Based on the total weight of the electrode composition, CNTs in the composite can be present in an amount within a range of from about 0.1 to about 10 wt %, e.g., from about 0.3 to about 5.0 wt %, e.g., from about 0.3 to about 3 wt %. In one implementation, for instance, the CNTs represent between 3 and 5 % by weight of the product electrode composition, such as, for instance, between 3 and: 3.5, 4 or 4.5 wt %; between 3.5 and: 4, 4.5 or 5 wt %; or from 4 and: 4.5 or 5 wt %; or from 4.5 and 5 wt%. In another implementation, CNTs are present in an amount within a range of from about 0.3 to: about 0.5, about 1.0, about 1.5, about 2.0, about 2.5; or from about 0.5 to: about 1.0, about 1.5, about 2.0, about 2.5, about 3; or from about 1.0 to: about 1.5, about 2.0, about 2.5, about 3.0; or from about 1.5 to: about 2.0, about 2.5, about 3.0; or from about 2.0 to: about 2.5, about 3.0; or from about 2.5 to about 3.0. Specific amounts within as well as outside these ranges can be selected.[ 00177 i In many cases, the amount of CNTs is equal to or, preferably, lower than the AC amount required to obtain the same or substantially the same electrode performance. In an alternative approach, reaching a performance level established with AC is expected to require lower amounts of CNTs, freeing extra volume for electroactive material.Docket: 2022622PCT[ 00178: In an illustrative LIB graphite anode composition, for example, the loading of the CNTs is no greater than about 5 wt % and often no greater than about 3 wt %, for example no greater than 1 wt %. In specific examples, the loading is within the rage of from about 0,1 wt % to 1,0 wt %, such as, within the range of from about 0.1 to about 0.5, or from about 0.5 to about 1 wt %. Other examples employ a loading withm the range of from about 1 to about 5 wt %, e.g., a loading of at least about 4.5, 4.0, 3,5, 3.0, 2.5, 2.0 or 1.5.[ 00179 i In an illustrative NCM cathode composition, CNTs are present in amounts less than or equal to about 5 wt %, e.g., no greater than about 3 wt %, for example no greater than 1 wt %. In specific examples, the loading of the multifunctional additive is within the rage of from about 0.1 wt % to 1.0 wt %, such as, within the range of from about 0.1 to about 0.5, or from about 0.5 to about 1 wt %. Other examples employ a loading within the range of from about 1 to about 5 wt %, e.g., a loading of at least about 4.5, 4.0, 3.5, 3.0, 2.5, 2.0 or 1.5.[ 00180 i Relative amounts of CNTs to the fibrillizable binder can be within a ratio of 5:1 to 0.1:10, e.g., from about 1:1 to 0.1:10, from 0.5:1 to 0.1:10; from 5:1 to 0.5:10, from 5:1 to 1:5; from 5:1 to 5: 10 by weight. In specific cases, the weight ratio is 1:3.[ 00181 J In one embodiment, the electrode composition contains active material in an amount of from about 90 wt % to about 99 wi %, e.g., to 96.0 wt %, polymer (including, for instance, fibrillizable binder and the polymeric constituent in the CNTs-polymer composite) in an amount of from about 1 wt % to about 5 wt % and CNTs in an amount of from about 0.3 wt % to about 5 wt %.[ 00182 i After mixing and processing, e.g., fibrillization, the composition, optionally sieved, can be formed into a product electrode by any suitable technique known in the art or developed in the future. In one implementation, the composition is formed into a film by calendaring, an operation which can be conducted at or above room temperature, e.g., at a temperature similar or close to the polymer glass transition temperature. In a typical calendaring operation, the composition is subjected to heat and pressure using an extruder. The softened material is passed through calendaring rolls (vertical, for instance) to prepare a product electrode sheet or film. In many embodiments, the film is free-standing, a propertyDocket: 2022622PCTthat can be described using a 150-μm thick film that stands on its own, any part of the film not being in contact with any type of support, e.g., a substrate.

[0183] A desired film thickness can be obtained by adjusting the gap between the rolls, and, in some situations, other process parameters.[ 00184 The roll temperature can be, for example, from about room temperature (20°C) to about 200°C. High roll temperatures may result in a thinner free-standing film on the first pass, whereas the opposite happens at lower temperature. Roll speed can vary. In illustrative examples, the roll speed is set from about 0.17 meters per minute (m / min) to about 1.3 m / min. A slower roll speed tends to produce a thinner free-standing film on the first pass compared to a faster roll speed. The hydraulic pressure employed can be within a range of from about 1,000 psi to about 7,000. Again, a higher pressure may result in a thinner free-standing film on the first pass compared to the thicker films obtained at a lower pressure.

[0185] Additional passes through the roll mill may be employed, reducing the film thickness until the desired thickness and loading are reached. In specific implementations, the film thickness is within a range of from about 50 μm to about 300 μm, e.g., from about 50 to about 200 μm, from about 100 μm to about 150 μm. Also possible are film thicknesses within a range of from 50 to 100, 50 to 150, 50 to 200, 50 to 250; or from 100 to 150, 100 to 200, 100 to 250, 100 to 300; or from 150 to 200, 150 to 250, 150 to 300; or from 200 to 250, from 200 to 300; or from 250 to 300 μm. Desired loadings may be about 10 mg / cm2to about 50 mg / cm2.[ o o 186] Free-standing films prepared in the solvent-free process described herein are expected to have good mechanical properties. One mechanical evaluation technique that can be relied upon relates to tensile strength and elastic modulus testing. For instance, an anode prepared using a CNTs-polymer composite is expected to have a tensile strength of at least lOOkPa, while the tensile strength of a NCM cathode film is expected to be at least 500kPa. In one illustrative example, the free-standing film has a tensile strength of at least 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa. A typical film thickness can be from about 30 μm to about 500 μm. In many cases, the mechanical performance of the filmDocket: 2022622PCTcomprising CNTs derived from the CNT-polymer composite was at least as good as that of a comparative film fabricated using unbound CNT.[ 00187 i In an optional operation, the film is thermally activated, e.g., to soften the binder and prepare the electrode product for being applied to a substrate. In the laboratory, this operation can be conducted using a hot plate, at 100° centigrade (C), for instance. Approaches for larger scale processes include temperature-controlled roll to roll calendars, convective and / or microwave driers, and so forth,[ o o 188 j The film, typically free-standing, contains active electrode material, CNTs (derived from the CNTs-polymer composite) and a processed, e.g., fibrillized, binder. Some films will also contain processed, e.g., fibrillized, polymer derived from the CNTs-polymer composite. [ o o 189 i To form an electrode, the film is applied to a conductive substrate or support. Anode substrates that can be utilized include but are not limited to copper, nickel, titanium, stainless steel, carbonaceous materials in the form of foil, mesh, foam, etched, or coated current collectors. Cathode substrates that can be used include but are not limited to aluminum, titanium, carbonaceous materials in the form of foil, mesh, foam, etched, coated current collectors. In one embodiment, the film is laminated to a. carbon-coated copper foil by calendaring the two together, using, for instance a. horizontal hot roller at a suitable roll temperature, roll speed and hydraulic pressure. Another example employs a carbon-coated aluminum current collector.[ 00190 J An electrically conductive glue (adhesive) can be employed to apply the film to the substrate, in some cases.[ o o 191 J The roll temperature can be within the range from about 60 to about 120°C.Temperatures that are too high can increase blister formation and poor adhesion, while temperatures that are too low can hamper adhesion.[ 00192 i Roll speed may be from about 0.17 rn / min to about 1.3 m / min, e.g., about 0.5 rn / min, while the hydraulic pressure may be set from about 500 psi to about 2,000 psi. Other settings can be employed. The pressure can be optimized to be high enough to promote adhesion to the substrate without altering loading, porosity or other properties. In someDocket: 2022622PCTimplementations, lamination is performed before setting the final thickness and / or porosity of the film electrode,[ 00193 i The formation of the film and its application to the substrate can be conducted in a single step in some cases. For instance, a powder electrode composition and a substrate foil can be fed together through calendaring rolls under conditions suitable to produce a laminate in which the composition is pressed to film thickness and adhered to the foil. In this approach, forming a free- or self-standing film is obviated.[ 00194 j The laminated structure can be shaped and / or sized for specific applications such as electrochemical cells, for instance, LIBs, e.g., rechargeable LIBs, and so forth.[ 00195 j Electrodes prepared as described herein can be incorporated into a lithium-ion battery according to methods known in the art, such as, for example, those described in " Lithium Ion Batteries Fundamentals and Applications", by Yuping Wu, CRC press, (2015). In specific implementations, the batteries are coin types such as, for example, 2032 coin-cells, 18650 cylindrical cells, pouch cells, and others.[ 001961 In an illustrative example, a LIB includes a cathode prepared by a dry process. The cathode contains CNTs, e.g., in an amount no greater than 5 wt %, active cathode material (e.g., NCM) and a fibrillized binder. In an illustrative anode, the active material and fibrillized binder can be present in an amount of at least 80 wt % and CNTs in an amount of no more than 5 wt %.[ o o 197 j Also present in the electrode is the polymer derived from the CNTs-polymer composite employed to prepare the electrode composition. This polymer can be identified by known analytical techniques as an individual constituent in cases in which the binder and the polymer in the composite are different. In some examples, the polymer derived from the CNTs-polymer composite is in a processed, e.g., fibrillized form.[ o o 198] The second (opposite) electrode in the battery also can be prepared using a solvent- free process. In one implementation, both electrodes in the battery contain a CNTs. It is also possible to prepare the second electrode by a conventional dry process (using AC, for instance), by a slurry or by another non-dry technique.Docket: 2022622PCT[ 00199 i In addition to the two electrodes, the typical LIB comprises a suitable electrolyte. Examples include, for instance, ethylene carbonate-dimethyl carbonate-ethylmethyl carbonate (EC-DMC-EMC), vinylene carbonate (VC), LiPF₆; ethylene carbonate-diethyl carbonate (EC- DEC, LiPF₆; or (EC-DMC), LiPF₆. In the laboratory, a separator that absorbs electrolyte and prevents electrical contact between electrodes, while allowing diffusion of Li ions, can be a suitable glass fiber micro filter (for example, Whatman GF / A). Membrane separators made of polypropylene / polyethylene (for example, Celgard 2300) also can be used in some cases.

[0200] The composition or morphology of electrodes and / or bateries described herein can be characterized by various techniques. Examples include but are not limited to electron microscopy, e.g., TEM, SEM, X-ray tomography, Raman spectrometry, and other suitable qualitative or quantitative analytical methods. In one example, SEM data for graphite electrodes prepared by a dry process using the multifunctional additive described herein revealed the presence of ribbon-like binder fibrils, indicating effective fibril lization.[ 002 o 1 J Solvent amounts or absence thereof can be evaluated by weight testing. This involves drying the wet-casted electrode until electrode weight reaches the value theoretically calculated based on known solids loading of the slurry, or until electrode weight stabilizes and does not change for minimum of 3 min. In the case of an electrode produced entirely in the absence of solvent, the weight remains the same over the evaluation period. Or, stated differently, the weight of the just prepared electrode (before any drying operation) is the same as or within I wt % of = the weight obtained by adding together the weight of the individual ingredients provided in the process).

[0202] Another approach that could be employed to detect a solvent (e.g., NMP) relies on attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy (FTIR-ATR), in conjunction with gas chromatography (GC). In many cases, dry-processed electrode films can be distinguished from slurry-based products by very low or undetectable levels of solvent residue. A substantially uniform binder distribution, without binder migration towards a film surface, is yet another feature that often characterizes an electrode product prepared by a solvent-free process.Docket: 2022622PCT[ 00203 i Flexibility properties characterizing the electrode, (its ability to resist cracking) can be measured by visual inspection upon bending a film by hand or using a Mandrel bend tester. In specific implementations, the electrode is evaluated and expected to pass a 10 mm diameter mandrel bar test without visible cracking to unaided eye. In an illustration, the electrode was found to pass a bending test using a pen of 8 mm diameter as a rod.

[0204] Electrode performance can be tested by procedures known in the art, or techniques adapted or developed. Suitable techniques include, for instance, in-plane and thru plane electrode conductivity, electrochemical impedance spectroscopy (EIS), constant current charge-discharge rate capability, hybrid pulse power capability (HPPC), cycle life test.

[0205] In many cases, electrodes prepared by the solvent free process described herein perform at least as well and often better (as measured by in-plane resistivity, initial capacity, or first cycle efficiency, for example) relative to a comparative (also referred to herein as a “reference”) electrode containing the same amounts of active electrode material (e.g., NCM), binder, and “polymer-free” or “unbound” CNTs (namely CNTs that are not provided in a CNTs-polymer composite).[ 00206 J In one illustration, a dry process cathode prepared using the composite described herein at CNTs loadings no higher than about 1 wt %, displays at least as good a performance (measured by 0.5C / 0.1C capacity retention, discharge capacity at 300thcycle, number of cycles per 20% of capacity loss) as a comparative (reference) electrode containing the same amounts (e.g., 1 wt %) of unbound or polymer-free CNT.[ o 0207 i Electrodes prepared using the solvent-free process described herein also are expected to have good mechanical properties. Mechanical evaluation techniques that can be relied upon include peeling testing (e.g., 90°, 180°, T-peel, various fixtures), pull testing, and bending testing (mandrel experiments), to name a few. In many cases, the electrode prepared with CNTs-polymer composite performed at least as well as a comparative electrode fabricated using unbound polymer-free CNT.[ o 0208 i Without wishing to be bound by a specific interpretation, it is believed that using CNTs, supplied in a CNTs-polymer composite, can produce ribbon-like binder strands or fibrils that can be long enough to wrap around and hold together particles of the electroactiveDocket: 2022622PCTmaterial. Thus, even at relatively low levels, the CNTs appeared capable of processing, e.g., fibrillating, the binder, generating effective conductive networks in electrodes, while also contributing to desirable mechanical properties.

[0209] Electrode compositions and methods described herein also can be used (e.g., incorporated) and / or adapted to the manufacture of other energy storage devices, such as, primary alkaline batteries, primary lithium batteries, nickel metal hydride batteries, sodium batteries, lithium sulfur batteries, lithium air batteries, and super capacitor. Methods of making such devices are known in the art and are described, for example, in " Battery Reference Book", by TR Crompton, Newness (2000).[ 0021 o ] The disclosure is further illustrated by the following non-limited examples.EXEMPIJFICATIONMaterials and Methods[ o 0211 1 The active electrode material employed was lithium nickel manganese cobalt oxide NCM622 (SNCM03006) from Targray. Water-soluble polymeric binder powders used in these examples to prepare aqueous dispersions and produce CNT-polymer composites included PVP DG1902454E from Zhangzhou HuaFu Chemical Co., Ltd), CMC, PEG. The PTFE suspension Teflon™ PTFE DISP 30 wras obtained from Chemours. PTFE 601X powder was obtained from Chemours and used as a fibrillizable binder to make electrode. PTFE fine particles dispersed in water, under the designation of POLYFLON™ PTFE D-210C, were obtained from Daikin Chemicals.[ 00212 i All CNF specifications were supplied by Cabot Corporation. Their characteristics are summarized in Table 1 above.[ 00213 i Several methods could be used to obtain CNT-containing pellets. For example, pellets that did not include polymer could be prepared by: (i) CNT powder compression, or (ii) by combining CNT powder with a liquid, typically water, pelletized by pasta maker (Baice, ZH-57) and followed by removing the liquid, e.g., by oven drying. Pellets that, contained both CNTs and polymer could be prepared by mechanically mixing CNTs powder with polymer, e.g., PTFE, powder. CNTs in powder could be mixed with a polymer dispersion such as, aDocket: 2022622PCTPTFE or a PVP dispersion, then pelletized and subjected to oven drying (in the case of both PVP or PTFE dispersions) or freeze drying (exemplified for PTFE dispersions).[ 00214 i Dustiness of pellets was assessed using a 20-mesh sieve with a diameter of 840 μm to separate free powder, which was then weighed to determine the pellet weight ioss as the dustmess. Crushing force was measured by subjecting the pellet's cross-section to stress using the probe of a texture analyzer from Lotun Science and recording the maximum stress as the crushing force.[ 002151 Generally, cathode electrodes were prepared in several stages. In a first step (SI), the CNT-containmg pellets were processed under suitable conditions to maximize conductive additive di persibility (e.g., by high shear mixing). In a second step (S2), electrode components were combined and mixed under conditions suitable to fibrillate the binder (e.g., by high shear mixing). The third step (S3) involved passing the powder blend from S2 through a vertical calender pre-set to the appropriate gap based on the desired film thickness. The free-standing films obtained from S3 were laminated onto a current collector in a fourth step (S4).[ 00216 J A similar sequence of steps can be followed to prepare anode electrodes.[ 00217 i The thickness of the solvent-free electrodes was measured using a manual drop gauge with the flat gauging contact head of 7.14 mm diameter. A manual die cutter was used to punch discs of diameter of 15 mm for cathode and 16 mm for anode.[ 00218 J Mechanical properties of free-standing dry' films, for instance, tensile strength and Young’s (elastic) modulus, were tested using Mecmesm MultiTest-dV motorized force tester with a 10N load. After the films were calendered to the desired thickness, they were cut into 70 x 20 mm strips using a die cut. Then, they were placed in the apparatus and the test program for the tensile test was performed.[ 00219 i The sheet resistance of the sol vent- free electrodes was measured with a Signatone Pro4-4400 commercial system (SP4 probe head connected to the rear of a Keithley 2410-C source meter). The reported values were normalized by the electrode thickness and reported as electrode resistivity in Ohm-cm (Clem).Docket: 2022622PCTExample i[ o 022 o ] Several types of pelletized CNT were prepared comprising various amounts of different types of CNT and polymers. Detailed compositions and CNT / polymer ratios together with key pellet characteristics are summarized in Table 2.Table 2| CNT pellet type CNT / polymer Approach Dustiness Crashing | (CNT type / weight ratio (%) force (g) i polymer)| CNT 1 / PVP 100 / 1 CNT1 powder + PVP disp. 0.7 432 oven drying| CNT2 / PTFE 19 / 1 CNT2 dispersion + PTFE 0.2 Not disp. freeze drying applicable CNT3 / PVP-1 200 / 1 CNT3 powder + PVP disp, 0.5 537 oven dryingCNT3 / PVP-2 100 / 1 CNT.3 powder + PVP disp, 0.4 566 oven dryingCNT3 / PTFE 200 / 1 CNT3 powder + PTFE 0.9 427 disp. — > oven dryingCNT3 Not applicable CNT3 powder 4- water --> 1.7 364 oven dryingCNT4 / CMC 100 / 1 CNT4 powder + CMC disp. > 0.6 590 oven dryingCNT4 / PEG 100 / 1 CNT4 powder + PEG disp. 0.38 597 oven dryingCNT4 / PVP 100 / 1 CNT4 powder + PVP disp. 0.67 492 oven dryingCNT4 Not applicable CNT4 powder + water 0.84 390 oven dryingCNT4 Not applicable CNT4 powder dry / / pelletizedCNT4 / PVP 100 / 1 CNT4 powder + PVP powder / / —>■ dry pelletized[ 00221J The pellets in Table 2 were prepared using different methods. One method involved the mixing of CNT dry powder (for instance, CNT1, CNT3 and CNT4) and a water¬ based polymer dispersion at different CNT / polymer ratios. The resulting mix appeared in a form of paste-like substance with high viscosity. As the next step, the water- containing CNTs-polymer substance underwent pelletization using a pasta maker (Baice, ZH-57) and was subsequently subjected to a drying process in an oven at 150°C. Water-based polymer dispersions were prepared by dissolving polymer powders such as PVP, CMC, PEG in water.Docket: 2022622PCTAnother example of water-based polymer dispersion used was a commercially available aqueous dispersion of Teflon™ PTFE DISP 30.[ 00222 i Another method involved the mixing of aqueous dispersion of CNT2 and a water¬ based polymer dispersion at 19 / 1 CNT-to-PTFE weight ratio, followed by subsequent freeze drying at -45°C for 4h and under vacuum for 4h. The water-based polymeric binder dispersion used for this preparative method included the PTFE Daikin Chemicals suspension D-210C.

[0223] For comparison, two sets of CNT3 and CNT4 pellets (from Table 2) were prepared without a polymer. The method involved dispersing of CNT dry powder in water at 13 wt. % CNT loading, followed by pelletization of the CNT-containing paste by the pasta maker and oven drying at 150 °C.

[0224] The dry pelletized CNT method, which compacts CNT powder or mixture of CNT powder with polymer powder using a pharmaceutical tablet machine under high pressure without any solvents, was also included in Table 1.[ o 0225 i By comparing CNT4, pelletized in the absence of polymer, with the three CNT4 / polymer composites, pelletized with different polymers as listed in Table 2, it was observed that combining the polymer with CNTs resulted in reduced dustiness and an increase in crushing force. An increased level of integration was also observed in the pellets composed of CNT3 / PTFE, CNT3 / PVP-1 and CNT3 / PVP-2, compared to the pellet made solely of CNT3. In addition, all pelletized CNT, including pelletized CNT / polymer composites, exhibited significantly reduced dustiness compared to the non-pelletized CNT (e.g., nonpelletized CNT3 dry powder has a dustiness of 99.37%). This suggests that pelletized CNT and pelletized CNT / polymer composite mitigates nanohazard exposure risks of airborne CNT particles and provides the benefit of safe CNT handling at manufacturing scale.Example 2[ 00226 J Free-standing dry-processed cathode films in this example were prepared in two stages.[ 00227 J As schematically shown in FIGS. 1 A through 1C, in the first stage (SI), electrode components were blended in sequence following a two-step operation using a ResodynDocket: 2022622PCTacoustic mixer and an IKA mill. In more detail, the first step of S 1 was performed to prepare a uniform distribution of powder components in the blend, which included a 10-minute pre¬ blending of a carbon additive and electrode active material NCM 622 (Targray) in the acoustic mixer at 90% intensity and auto frequency, followed by the addition of the polymer PTFE 601X binder (Chemours) and blending at the same settings for 20 more minutes. Conductive additive in non-pelletized (fluffy) form was used as is. Conductive additive in pelletized form (obtained as described in Example 1) was pre-processed before mixing with electrode active material, which included mixing in an IKA Tube Mill for 3 min at 25,000 rpm for 5 cycles (15 min of total mixing) with 2 min resting period between the cycles.

[0228] The second step of SI, involving fibrillating the blend, was further processed using IKA Tube Mill 100 for 15 sec at 25,000 rpm for 6 cycles and 3 min at 5000 rpm for 1 cycle with 45 sec resting period between the cycles.[ o 0229 i In the second stage (S2), the powder blend obtained in S 1 was passed through a vertical calender at 100 °C to obtain free-standing films, as seen in FIG. ID, having a thickness between 30 and 130 pm.[ 00230 J The carbon additives, namely pristine (non-pelletized) CNT1 (Table 1), CNT1 / PVP composite and CNT2 / PTFE composite pelletized by different methods (Table 2) were used to prepare free-standing cathode films according to the formulations listed in Table 3. All films were prepared by a dry process and contained the carbon additive at a loading of 2 wt.%, NCM622 (94 wt.%) and PTFE (4 wt. %). In Table 3, “pass” indicates that a continuous and flexible film could be formed with the film thickness <150.urn; “fail” indicates that no continuous and flexible film could be formed with film thickness <150 jun.Table 3Formulation Active Carbon Additive Binder Ave. Dry Free-standing ID Material Film Film Quality Thickness(pm)Al 94% NCM 2% non-pelletized 4% PTFE 110 Pass CNT1A2 94% NCM 2% pelletized 4% PTFE 113 PassCNT1 / PVPA3 94% NCM 2% CNT2 / PTFE 4% PTFE 189 FailDocket: 2022622PCT[ 00231J As depicted in FIG. 2, the dry cathode film A2, prepared with the CNT1ZPVP pellet, displayed enhanced tensile strength compared to the cathode film Al made with pristine CNT1 powder. This suggests that there are strengthened interactions between the PTFE binder and CNTs for improved reinforcement and film quality.[ 00232 i The dry cathode film (formulation A3) made with the CNT2 / PTFE composite comprising a non-pulverized CNT material resulted in a thicker electrode at 189pm and the tensile strength at 250kPa, which was notably lower than the tensile strengths observed with other dry cathodes in this example, thus was labelled “fail” in Table 3. This appeared to confirm the advantages of using processed (pulverized) CNTs over pristine (non-pulverized) CNTs in the CNT / polymer composite.Example 3[ 00233 j The free-standing NCM electrode films in this example were prepared by the 2- stage procedure described in Example 2. The carbon additives employed were pellets of the CNT3 / PVP-1 and CNT3 / PVP-2 composites (from Table 2). CNT2 and CN T3, where CNT3 is the pulverized version of CNT2 were used for comparison.[ 002341 The electrode formulations employed (labeled Bl through B4), are listed in Table 4, below. All dry electrode films were prepared by a dry process and contained the carbon additive at a loading of 1 wt.%, NCM622 (96 wt. %) and PTFE (3 wt. %).Table 4Formulation ID Active material Carbon additive Binder Ave. Film |Thickness | BI 96% NCM 1% non-pelletized 3% PTFE 110 CNT2B2 96% NCM 1% non-pelletized 3% PTFE 116 CNT3B3 96% NCM 1% pelletized 3% PTFE 111 CNT3 / PVP-1B4 96% NCM 1% pelletized 3% PTFE 111CNT3 / PVP-2[ 002351 The tensile strength and elastic modulus of the selected dry cathode films shown in Table 4 are presented in FIGS. 3 and 4.Docket: 2022622PCT[ 002361 As seen in FIG. 3, although the dry electrode film B3 made with pelletized CNT3ZPVP-1 composite had a diminished tensile strength and higher elastic modulus compared to the electrode film B2 made with non-pelletized CNT3 powder, its mechanical performance was on par with dry electrode film Bl made with dry non-pelletizedCNT2 powder.

[0237] The influence of the polymer loading in the composite was evident when comparing CNT3ZPVP composites with different CNT / polymer ratios in Formulations B3 and B4. As illustrated in FIG, 4, the electrode derived from formulation B3, which utilized a composite CNT3 / PVP-1 with CNT / polymer weight ratio at 200 / 1, exhibited a lower (improved) elastic modulus compared to formulation B4, which was made with CNT3 / PVP-2 composite containing CNT / polymer weight ratio at 100 / 1. This further suggests that lower polymer amounts in the CNT / polymer composite may be preferred for improved flexibility of free-standing dry -processed films.Example 4[ 00238 i A series of dry-process cathodes (labeled Cl through C4) were prepared by laminating -dry-processed free-standing cathode films, prepared following S1-S2 as described in Example 2, onto a current collector (S3). In more detail, free-standing electrode films obtained in S2 were laminated on the carbon-coated, 17-pm thick Al foil by calendaring them together through a vertical calender at 100 °C to obtain the electrode.[ 00239 J The electrode formulations employed, and the characteristics of the resulting cathodes are listed in Table 5 below. All dry cathodes films contained NCM622 (96 wt.%), PTFE (3 wt.%), and 1 wt.% carbon additives.Docket: 2022622PCTTable 5Electrode Formulation Active material Electrode ID loading [mg / cm2] density [g / cm’J Cl 96% NCM, 1% non-pelletized CNT2, 25.7 3.63% PTFEC2 96% NCM, 1% non-pelletized CNT3, 24.6 3.83% PTFEC3 96% NCM, 1% pelletized CNT3 / PVP-1, 25.4 3.73% PTFEC4 96% NCM, 1% pelletized CNT3, 3% 25.8 3.7PTFE[ 002401 The cathodes from Table 5 were tested in 2032 full coin cells. Fifteen-millimeter in diameter discs were punched for coin-cell preparation and dried at 100°C under vacuum for a minimum of 4 hours. Discs were calendered at the desired electrode density with a manual roll press and assembled into 2032 coin-cells in an argon-filled glove box (M-Braun) for testing against slurry-processed graphite anodes which contained 3% CB, 5% PVDF, 92% natural graphite, at anodic access of 1.2, measured as a negative to positive electrodes capacity ratio (N / P). 2325 Celgard film was used as the separator. The 1 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate-dimethyl carbonate-ethyl methyl carbonate (EC-DMC-EMC, 1:1:1 by wt.) with 1 wt.% vinylene carbonate (VC) from E-Lyte was used as electrolyte. The room temperature (25 °C) rate performance of the full coin cells was measured by first forming them by four C / 20-D / 20 charge-discharge cycles, then charging and discharging them at each rate for four cycles at C / 10, C / 5, C / 3, C / 2, 1C, and 2C, respectively. Cycling performance testing of the full cells was carried out at 25°C using C / 3 charge and C / 3 discharge rate after C-rate capability test. The cells comprising cathode C3 underwent additional formation cycle at C / 20 charge and C / 20 discharge before cycling test.

[0241] Summarized in FIG. 5 are the results of rate capability test showing 0.5C / 0.1C discharge capacity retention for the cathodes from Table 5. The results indicate that, in addition to mitigating the nanomaterial handling risks during production, the 1% pelletized CNT3 / PVP-1 composite and 1% pelletized CNT3 -containing electrodes performed on par with those containing non-pelletized CNTs alone, showing no adverse effect from containing additional polymer and / or being handled in pelletized form.Docket: 2022622PCT[ 00242 i FIG. 6A displays a plot illustrating the room temperature cycling of full coin cells with dry cathodes comprising n on-pelletized CNT3 and pelletized CNT3 / PVP-1 composite up to 330 cycles. The capacity loss rate (in mAh per cycle) was calculated by fitting the linear region of cycling curves (cycles 20-330) with a simple linear function Capacity = a + b ■ Cycle#, where b is a slope representing capacity loss rate. The results are summarized in Table 6. R-square (R2) of the fit was 0.97. See also FIG. 6B. Data modeling based on capacity fading indicate that the electrode made with pelletized CNT3 / PVP-1 composite can have longer cycle life by the time its capacity drops by 20% compared to the electrode made with CNT3 powder alone, which indicated the structural and electrochemical stability of the former. This prediction was further supported by experimental data collected after 1000 cycles (see also FIG. 6C).Table 6Electrode Formulation Discharge Capacity loss rate #Cycles per ID Capacity at (mAh / cyc) 20% of 300cyc (mAh) Capacity Loss C2 96%NCM, 1% 6.064.0.08 0.00134±9.66E- 966.8Ot60.73CNT3, 053% PTFEC3 96% NCM, 1% 5.94±0.16 0.00126±1.57E- 1120.66±115.5CNT3 / PVP-1, 3% 04PTFE

[0243] FIG. 6C displays a plot to show the room temperature capacity retention of full coin cells with dry cathodes Cl through C4 tested up to 1000 cycles. The electrode made with pelletized CNT3 / PVP-1 composite showed improved capacity retention by 7.3% compared to the electrodes made with non-pelletized CNT3 powder and by 8.4% compared to electrodes made with the commercially available CNT2 dry powders alone, winch indicated the structural and electrochemical stability and enhanced performance of the former.Example 5[ 00244 i A series of free-standing dry-processed cathode films in this example were prepared in two stages (SI, S2) as described below and then laminated onto a current collector (S3) for electrochemical testing. Electrode powder processing in SI was carried out inDocket: 2022622PCTsequential steps, as follows, enabling improved dispersibility of CNTs and lower binder loading in the electrode formulation.[ 00245 i Step SI -A: Initially, CNT pellets or non-pelletized CNT were mixed with the active material NCM in an Eirich mixer at a speed of 25 m / s in counter-rotation mode, and the mixture was processed for 6 minutes to form the Mixture 1.

[0246] Step Sl-B: Following the initial mix, the mixture 1 was further processed with the binder PTFE in the Eirich mixer, but at a lower speed of 5 m / s in co-rotation mode for 3 minutes. The reduced speed and shorter mixing time helped to incorporate the binder gently without over-fibrilize it, ensuring it effectively binds the components without clumping.

[0247] Step Sl-C: The mixed material was then subjected to extrusion using a twin-screw extruder (TSE). The screw' rotation speeds are varied at 400 rpm for all samples. This variation in speed allowed for the adjustment of shear and mixing intensity, which can be optimized for different formulations to ensure uniformity and proper compaction of the material.

[0248] Step Sl-D: After extrusion, the material w'as milled into flakes using an IKA mill. The milling was performed at 5000 rpm, with durations set at 20 seconds, 40 seconds, and 60 seconds. This step reduces the pelletized material into finer flakes, improving the surface area and ensuring a more uniform texture, which wa.s crucial for the next processing step.

[0249] Then, it followed the similar calendaring as Example 2 and laminating onto current collector stages S2 and S3 as described m Example 2 and Example 4, respectively.

[0250] The electrode formulations employed, and the characteristics of the resulting cathodes are listed in Table 7 below. All dry cathodes films contained NCM622 (97 wt.%), PTFE (2 wt.%), and 1 wt.% carbon additives.Docket: 2022622PCTTable 7Electrode Formulation | Active material Electrode ID | loading density | [mg / cm2] [g / cm3]DI 97% NCM622, 1% pelletized CNT3, 2% PTFE 32.96 0.9D2 97% NCM622, 1% non-pelletized CNT2, 2% 33.30 0.9PTFE

[0251] Overall, as shown in FIG. 7, the dry electrodes made with the CNT3 pellets are on par with the commercially available non-pelletized pristine CNT2 in the mechanical film tensile strength and exhibit elastic modulus improved by 9.7%.[ 00252 i The SEM and elemental mapping images of Electrode DI made with CNT3 pellet as shown in FIG.8 demonstrated the uniform distribution of CNTs after processing, which were well-dispersed across the surface of NCM particles in the electrode. The CNTs appeared to be evenly integrated, which will contribute to the conductivity across the structure.Additionally, SEM images combined with the F and C elemental maps clearly showed that the PTFE binder has been effectively fibrillated, with fibrils extending across the electrode. This suggested that the fibrillation process has successfully formed a network of PTFE fibrils, promoted structural integrity and enhanced the overall performance of the electrode made with pelletized CNT3. The rate performance data shown in FIG.9 demonstrated that electrodes made with CNT3 pellet (Electrode DI) outperformed the one made with non-pelletized CNT2 dry powder (Electrode D2) at lower C-rates (C / 5 to C / 2). Overall, the performance suggests that the CNT3 pellet without any polymer also offers a balance between discharge capacity and safety.ASPECTS[ 00253 i Aspect 1. A method for preparing an electrode composition, the method comprising:Docket: 2022622PCTcombining an active electrode material, a binder and a carbon nanotubes-polymer composite; andprocessing the binder in the presence of the carbon nanotubes-polymer composite, wherein, the method is conducted in the absence of solvent.[ 00254: Aspect 2. The method of aspect 1, wherein carbon nanotubes in the carbon nanotubes-polymer composite are multi-walled multifunctional carbon nanotubes.[ 00255 i Aspect 3. The method of aspect 1 or 2, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 80 to about 500 m2 / g.[ 002561 Aspect 4. The method of aspect 1 or 2, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 200 to about 500 m2 / g.

[0257] Aspect 5. The method of any of aspect 1 -4, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.[ o 0258 i Aspect 6. The method of any of aspect 1-5, wherein carbon nanotubes in the carbon nanotubes-polymer composite have an average particle size (Dso) within a range of from about 5 to about 500 microns, as determined by laser diffraction analysis.

[0259] Aspect 7, The method of any of aspect 1 -6, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder.

[0260] Aspect 8. The method of any of aspects 1 through 7, wherein the carbon nanotube- polymer composite is a dust-free, loose particulate material.

[0261] Aspect 9. The method of any of aspects 1 through 8, wherein the carbon nanotubes-polymer composite is in pellet form.

[0262] Aspect 10, The method of any of aspects 1 through 9, wherein the carbon nanotubes-polymer composite contains a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.Docket: 2022622PCT[ 00263 i Aspect 11. The method of any of aspects 1 through 10, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.[ 00264 i Aspect 12. The method of aspect 11, wherein the PF AS polymer is PTFE.[ o 0265 ] Aspect 13. The method of any of aspects 1 through 10, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

[0266] Aspect 14. The method of aspect 13, wherein the PFAS-free polymer is PVP or HNBR.

[0267] Aspect 15. The method of any of aspects 1 through 14, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100:0.1.[ 00268 i Aspect 16. The method of any of aspects 1 through 14, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10:1 to about 100:0.1.

[0269] Aspect 17, The method of any of aspects 1 through 16, wherein the active electrode material, the binder, the carbon nanotubes-polymer composite and the electrode composition are loose particulate materials.

[0270] Aspect 18. The method of any of aspects 1 through 17, wherein carbon nanotubes in the carbon nanotubes-polymer composite are present in amount of no greater than about 5 % by weight based on the total weight of the electrode composition.

[0271] Aspect 19, The method of any of aspects 1 through 18, wherein the active electrode material is a lithium transition metal compound.

[0272] Aspect 20, The method of any of aspects 1 through 18, wherein the active electrode material is graphite, a silicon-containing compound or any combination thereof.

[0273] Aspect 21, The method of any of aspects 1 through 20, wherein the method is conducted in the presence of the carbon nanotubes in the carbon nanotubes-polymer composite as the only fibrillating agent.Docket: 2022622PCT[ 00274: Aspect 22. The method of any of aspects 1 through 21, wherein the binder is a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.[ 00275: Aspect 23. The method of any of aspects 1 through 21, wherein the binder contains polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or any combination thereof.

[0276] Aspect 24. The method of any of aspects 1 through 23, wherein the binder includes a polymer that is the same or substantially the same as the polymer in the carbon nanotubes- polymer composite.

[0277] Aspect 25. The method of any of aspects 1 through 24, wherein processing the binder includes a high shear operation sufficient to fibri llize a fibrillizable binder.

[0278] Aspect 26. The method of any of aspects 1 through 24, wherein processing the binder includes a high shear operation sufficient to deform a non-fibrillizable binder.

[0279] Aspect 27. The method of any of aspects 1 through 26, wherein the electrode composition contains active material in an amount from about 92 wt % to about 99.8 wt %, binder in an amount of from about 0.1 wt % to about 5 wt % and carbon nanotubes-polymer composite in an amount of from about 0.1 wt % to about 3 wt %..

[0280] Aspect 28, A method further comprising applying the electrode composition prepared according to any of the preceding aspects to a conductive substrate, to form a battery electrode.[ o 0281 ] Aspect 29. A method further comprising calendaring the electrode composition prepared according to any of aspects 1 through 27 to form a film.[ o 0282 ] Aspect 30. The method of aspect 29, wherein the film is free-standing and has a thickness within a range of from about 30 to about 500 microns.[ o 0283 ] Aspect 31. The method of aspect 30, wherein the film has a tensile strength of at least about 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa.[ o 0284 ] Aspect 32. A method comprising applying the film according to any of aspects 29 through 31 to a conductive substrate to form a battery electrode.Docket: 2022622PCT[ 00285 i Aspect 33. The method of any of aspects 1 through 32, wherein the carbon nanotubes-polymer composite is prepared by a method that includes:combining carbon nanotubes and a polymer to form a mixture, andremoving a liquid from the mixture to obtain the carbon nanotubes-polymer composite, wherein the carbon nanotubes, the polymer, or both is / are provided in a dispersion.

[0286] Aspect 34. The method of aspect 33, wherein the dispersion is an aqueous dispersion.

[0287] Aspect 35. The method of any of aspects 1 through 32, wherein the carbon nanotubes-polymer composite is prepared by combining carbon nanotubes and the polymer, wherein the carbon nanotubes, the polymer, or both is / are provided as a dry powder.[ 00288 Aspect 36. A method for preparing an electrode composition, the method comprising:(a) subjecting a binder to high shear conditions in the presence of a carbon nanotubes-polymer composite to process the binder; and(b) adding an electrode active material before, during or after step (a), wherein, the method is conducted without adding a solvent.

[0289] Aspect 37. The method of aspect 36, wherein carbon nanotubes in the carbon nanotubes-polymer composite are multi-walled multifunctional carbon nanotubes.

[0290] Aspect 38. The method of aspect 36 or 37, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 80 to about 500 m2 / g.

[0291] Aspect 39. The method of aspect 36 or 37, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 200 to about 500 m2 / g.

[0292] Aspect 40. The method of any of aspects 36-39, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.Docket: 2022622PCT[ 00293 i Aspect 41. The method of any of aspect 36-40, wherein carbon nanotubes in the carbon nanotubes-polymer composite have an average particle size (Dso) within a range of from about 5 to about 500 microns, as determined by laser diffraction analysis.

[0294] Aspect 42. The method of any of aspect 36-41, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder,

[0295] Aspect 43. The method of any of aspects 36 through 42, wherein the carbon nanotube-polymer composite is a dust-free, loose particulate material.

[0296] Aspect 44. The method of any of aspects 36 through 43, wherein the carbon nanotubes-polymer composite is in pellet form.

[0297] Aspect 45. The method of any of aspects 36 through 44, wherein the carbon nanotubes-polymer composite contains a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.[ o 0298 ] Aspect 46. The method of any of aspects 36 through 45, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.[ o 0299 Aspect 47. The method of aspect 46, wherein the PF AS polymer is PTFE.

[0300] Aspect 48. The method of any of aspects 36 through 45, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

[0301] Aspect 49. The method of aspect 48, wherein the PFAS-free polymer is PVP or HNBR.

[0302] Aspect 50. The method of any of aspects 36 through 49, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100:0.1.[ 00303 Aspect 51. The method of any of aspects 36 through 49, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10:1 to about 100:0.1.Docket: 2022622PCT

[0304] Aspect 52. The method of any of aspects 36 through 51, wherein the active electrode material, the binder, the carbon nanotubes-polymer composite and the electrode composition are loose particulate materials.

[0305] Aspect 53. The method of any of aspects 36 through 52, wherein carbon nanotubes in the carbon nanotubes-polymer composite are present in amount of no greater than about 5 % by weight based on the total weight of the electrode composition,[ 003061 Aspect 54. The method of any of aspects 36 through 53, wherein the active electrode material is a lithium transition metal compound.[ 00307 i Aspect 55. The method of any of aspects 36 through 53, wherein the active electrode material is graphite, a silicon-containing compound or any combination thereof. [ 00308 i Aspect 56. The method of any of aspects 36 through 55, wherein the method is conducted in the presence of the carbon nanotubes in the carbon nanotubes-polymer composite as the only fibri Hating agent.

[0309] Aspect 57, The method of any of aspects 36 through 56, wherein the binder is a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.

[0310] Aspect 58, The method of any of aspects 36 through 57, wherein the binder contains polytetrafluoroethylene (PTFE), poly vinylidene fluoride (PVDF), or any combination thereof.[ 00311 1 Aspect 59. The method of any of aspects 36 through 58, wherein the binder includes a polymer that is the same or substantially the same as the polymer in the carbon nanotubes-polymer composite.

[0312] Aspect 60, The method of any of aspects 36 through 59, wherein processing the binder includes a high shear operation sufficient to fibri llize a fibrillizable binder.

[0313] Aspect 61, The method of any of aspects 36 through 59, wherein processing the binder includes a high shear operation sufficient to deform a non-fibrillizable binder.

[0314] Aspect 62, The method of any of aspects 36 through 61, wherein a mixing operation combining two or more ingredients is conducted at shear conditions that are lower than shear conditions employed in processing the binder.Docket: 2022622PCT

[0315] Aspect 63. A method further comprising applying the electrode composition prepared according to any of aspects 36 through 62 to a conductive substrate, to form a battery electrode.

[0316] Aspect 64. A method further comprising calendaring the electrode composition prepared according to any of aspects 36 through 62 to form a film.

[0317] Aspect 65. The method of aspect 63, wherein the film is free-standing and has a thickness within a range of from about 30 to about 500 microns,

[0318] Aspect 66. The method of aspect 65, wherein the film has a tensile strength of at least about 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa.

[0319] Aspect 67. A method comprising applying the film according to any of aspects 64 through 66 to a conductive substrate to form a battery electrode.

[0320] Aspect 68. The method of any of aspects 36 through 67, wherein the carbon nanotubes-polymer composite is prepared by a method that includes:combining carbon nanotubes and a polymer to form a mixture, andremoving a liquid from the mixture to obtain the carbon nanotubes-polymer composite, wherein the carbon nanotubes, the polymer, or both is / are provided in a dispersion.

[0321] Aspect 69. The method of aspect 68, wherein the dispersion is an aqueous dispersion.

[0322] Aspect 70. The method of any of aspects 36 through 67, wherein the carbon nanotubes-polymer composite is prepared by combining carbon nanotubes and the polymer, wherein the carbon nanotubes, the polymer, or both is / are provided as a dry powder.

[0323] Aspect 71. A dry processed film comprising: an active electrode material, a processed binder and a carbon nanotubes-polymer composite, wherein before any drying operation, the film contains solvent residue in an amount no greater than 1 wt % relative to the weight of the film electrode, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 80 to about 500 m2 / g.Docket: 2022622PCT

[0324] Aspect 72. The dry processed film of aspect 71, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 200 to about 500 m2 / g.

[0325] Aspect 73. The dry processed film of aspect 71 or 72, wherein the dry processed film is free standing or laminated to a substrate,

[0326] Aspect 74. The dry processed film of any of aspects 71 through 73, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are multi -walled multifunctional carbon nanotubes.

[0327] Aspect 75. The dry processed film of any of aspects 71 through 74, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.

[0328] Aspect 76, The dry processed film electrode of any of aspects 71 through 75, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have an average particle size (Dso) within a range of from about 5 to about 500 microns as measured by laser diffraction analysis.

[0329] Aspect 77, The dry processed film of any of aspect 71 through 76, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder.

[0330] Aspect 78, The dry processed film of any of aspects 71 through 77, wherein the active electrode material, the binder, the carbon nanotubes and the electrode composition are particulate materials.

[0331] Aspect 79. The dry processed film of any of aspects 71 through 78, wherein the active electrode material is a lithium transition metal compound.

[0332] Aspect 80. The dry processed film of any of aspects 71 through 78, wherein the active electrode material is graphite, a silicon-contaming compound, or any combination thereof.

[0333] Aspect 81, The dry processed film of any of aspects 71 through 80, wherein carbon nanotubes in the carbon nanotubes-polymer composite are present in amount of no greater than about 5 % by weight based on the total weight of the electrode composition.Docket: 2022622PCT

[0334] Aspect 82. The dry processed film of any of aspects 71 through 81, wherein the carbon nanotubes in the caron nanotubes-polymer composite are the only fibnllating agent.

[0335] Aspect 83. The dry processed film of any of aspects 71 through 82, wherein the binder is a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.

[0336] Aspect 84. The dry processed film of any of aspects 71 through 83, wherein the binder contains polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or any combination thereof

[0337] Aspect 85. The dry processed film of any of aspects 71 through 84, wherein the binder includes a polymer that is the same or substantially the same as the polymer m the carbon nanotubes-polymer composite.

[0338] Aspect 86. The dry processed film of any of aspects 71 through 85, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.

[0339] Aspect 87. The dry processed film of aspect 86, wherein the PF AS polymer is PTFE.

[0340] Aspect 88. The dry processed film of any of aspects 71 through 85, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

[0341] Aspect 89. The dry processed film of aspect 88, wherein the PFAS-free polymer is PVP or HNBR.

[0342] Aspect 90. The dry processed film of any of aspects 71 through 89, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100: 0, 1.

[0343] Aspect 91, The method of any of aspects 71 through 89, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10:1 to about 100:0.1.

[0344] Aspect 92. The dry processed film of any of aspects 71 through 91, wherein the film is free-standing and has a thickness within a range of from about 30 to about 500 microns.Docket: 2022622PCT

[0345] Aspect 93. The dry processed film of aspect 92, wherein the film has a tensile strength of at least about 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa.

[0346] Aspect 94. An electrode comprising the dry’ processed film of any of aspects 71 through 93.

[0347] Aspect 95. The electrode of aspect 94, wherein the dry processed film is applied to a substrate.

[0348] Aspect 96. A battery’ comprising the electrode of aspect 94 or aspect 95.

[0349] Aspect 97. A carbon nanotubes-polymer composite, comprising:a plurality of multi-walled carbon nanotubes; anda polymer,wherein the carbon nanotubes-polymer composite is in pellet form and has a weight loss of 5% or less upon screening the carbon nanotubes-polymer composite through a 20-mesh sieve with 840 micron openings.

[0350] Aspect 98. The carbon nanotubes-polymer composite of aspect 97, wherein the composite has a weight loss of 3% or less upon screening the carbon nanotubes- polymer composite through a 20-mesh sieve with 840 micron openings.

[0351] Aspect 99. The carbon nanotubes-polymer composite of aspect 97, wherein the composite has a weight loss of 1% or less upon screening the carbon nanotubes- polymer composite through a 20-mesh sieve with 840 micron openings.

[0352] Aspect 100. The carbon nanotubes-polymer composite of any of aspects 97-99, wherein the carbon nanotubes have a BET within a range of from about 80 to about 500 m2 / g.

[0353] Aspect 101. The carbon nanotubes-polymer composite of any of aspects 97-100, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.

[0354] Aspect 102. The carbon nanotubes-polymer composite of any of aspects 97-101, wherein carbon nanotubes in the carbon nanotubes-polymer composite have an averageDocket: 2022622PCTparticle size (D50) within a range of from about 5 to about 500 microns, as determined by laser diffraction analysis.

[0355] Aspect 103. The carbon nanotubes-polymer composite of any of aspects 97-102, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder.

[0356] Aspect 104. The carbon nanotubes-polymer composite of any of aspects 97-103, wherein the carbon nanotubes-polymer composite contains a PFAS polymer,

[0357] Aspect 105. The carbon nanotubes-polymer composite of any of aspects 97-104, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

[0358] Aspect 106. The car bon nanotubes-polymer composite of any of aspects 97- 105, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100:0.1.

[0359] Aspect 107. The carbon nanotubes-polymer composite of any of aspects 97-106, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10:1 to about 100:0.1.

[0360] Aspect 108: A dry processed film comprising: an active electrode material, a processed binder, and the carbon nanotubes-polymer composite of any of aspects 97 through 107.

[0361] Aspect 109: An electrode comprising the dry processed film of aspect 108.

[0362] Aspect 110: A battery comprising the electrode of aspect 109,

[0363] While this disclosure has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the disclosure encompassed by the appended claims

Claims

Docket: 2022622PCTCLAIMSWhat is claimed is:

1. A method for preparing an electrode composition, the method comprising:combining an active electrode material, a binder and a carbon nanotubes-polymer composite; andprocessing the binder in the presence of the carbon nanotubes-polymer composite, wherein,the method is conducted in the absence of solvent.

2. A method for preparing an electrode composition, the method comprising:(a) subjecting a binder to high shear conditions in the presence of a carbon nanotubes- polymer composite to process the binder; and(b) adding an electrode active material before, during or after step (a), wherein,the method is conducted without adding a solvent.

3. The method of claim 1 or 2, wherein carbon nanotubes in the carbon nanotubes-polymer composite are multi-walled multifunctional carbon nanotubes.

4. The method of any preceding claim, wherein carbon nanotubes in the carbon nanotubes- polymer composite have a BET within a range of from about 80 to about 500 m2 / g.

5. The method of any preceding claim, wherein carbon nanotubes in the carbon nanotubes- polymer composite have a BET within a range of from about 200 to about 500 m2 / g.

6. The method of any preceding claim, wherein carbon nanotubes in the carbon nanotubes- polymer composite have a diameter within a range from about 2 to about 50 nanometers.Docket: 2022622PCT7. The method of any preceding claim, wherein carbon nanotubes in the carbon nanotubes- polymer composite have an average particle size (D50) within a range of from about 5 to about 500 microns, as determined by laser diffraction analysis.

8. The method of any preceding claim, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder.

9. The method of any preceding claim, wherein the carbon nanotube-polymer composite has a weight loss of 5% or less upon screening the carbon nanotubes-polymer composite through a 20-mesh sieve with 840 micron openings.

10. The method of any preceding claim, wherein the carbon nanotubes-polymer composite is in pellet form.I I. The method of any preceding claim, wherein the carbon nanotubes-polymer composite contains a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.

12. The method of any preceding claim, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.

13. The method of claim 12, wherein the PF AS polymer is PTFE.

14. The method of any of claims 1 through 11, wherein the carbon nanotubes-polymer composite contains a PF AS -free polymer.

15. The method of claim 14, wherein the PFAS-free polymer is PVP or HNBR.

16. The method of any preceding claim, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100: 0.1.Docket: 2022622PCT17. The method of any of claims 1 through 16, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10: 1 to about 100:0.1.

18. The method of any preceding claim, wherein the active electrode material, the binder, the carbon nanotubes-polymer composite and the electrode composition are loose particulate materials.

19. The method of any preceding claim, wherein carbon nanotubes in the carbon nanotubes- polymer composite are present in amount of no greater than about 5 % by weigh t based on the total weight of the electrode composition.

20. The method of any preceding claim, wherein the active electrode material is a lithium transition metal compound.

21. The method of any preceding claim, wherein the active electrode material is graphite, a silicon-containing compound or any combination thereof.

22. The method of any preceding claim, wherein the method is conducted in the presence of the carbon nanotubes in the carbon nanotubes-polymer composite as the only fibrillating agent.

23. The method of any preceding claim, wherein the binder is a fibrillizable binder, a non- fibrillizable binder, or any combination thereof.

24. The method any preceding claim, wherein the binder contains polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or any combination thereof.

25. The method of any preceding claim, wherein the binder includes a polymer that is the same or substantially the same as the polymer in the carbon nanotubes-polymer composite.Docket: 2022622PCT26. The method of any preceding claim, wherein processing the binder includes a high shear operation sufficient to fibrillize a fibrillizable binder.

27. The method of any preceding claim, wherein processing the binder includes a high shear operation sufficient to deform a non-fibrillizable binder.

28. The method of any preceding claim, wherein the electrode composition contains active material in an amount from about 92 wt % to about 99.8 wt %, binder in an amount of from about 0.1 wt % to about 5 wt % and carbon nanotubes-polymer composite in an amount of from about 0.1 wt % to about 3 wt %..

29. A method further comprising applying the electrode composition prepared according to any of the preceding claims to a conductive substrate, to form a battery electrode.

30. A method further comprising calendaring the electrode composition prepared according to any of claims 1 through 29 to form a film.

31. The method of claim 30, wherein the film is free-standing and has a thickness within a range of from about 30 to about 500 microns.

32. The method of claim 31, wherein the film has a tensile strength of at least about 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa.

33. A method comprising applying the film according to any of claims 30 through 32 to a conductive substrate to form a battery electrode.

34. The method of any of claims 1 through 33, wherein the carbon nanotubes-polymer composite is prepared by a method that includes:combining carbon nanotubes and a polymer to form a mixture, andremoving a liquid from the mixture to obtain the carbon nanotubes-polymer composite, wherein the carbon nanotubes, the polymer, or both is / are provided in a dispersion.Docket: 2022622PCT35. The method of claim 34, wherein the dispersion is an aqueous dispersion,36. The method of any of claims 1 through 33, wherein the carbon nanotubes-polymer composite is prepared by combining carbon nanotubes and the polymer, wherein the carbon nanotubes, the polymer, or both is / are provided as a dry powder.

37. A dry processed film comprising: an active electrode material, a processed binder and a carbon nanotubes-polymer composite, wherein before any drying operation, the film contains solvent residue in an amount no greater than 1 wt % relative to the weight of the film electrode, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 80 to about 500 m2 / g.

38. The dry processed film of claim 37, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a BET within a range of from about 200 to about 500 m2 / g.

39. The dry processed film of claim 37 or 38, wherein the dry processed film is free standing or laminated to a substrate.

40. The dry processed film of any of claims 37 through 39, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are multi-walled multifunctional carbon nanotubes.

41. The dry processed film of any of claims 37 through 40, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.

42. The dry processed film electrode of any of claims 37 through 41, wherein the carbon nanotubes in the carbon nanotubes-polymer composite have an average particle size (Dso) within a range of from about 5 to about 500 microns as measured by laser diffraction analysis.Docket: 2022622PCT43. The dry processed film of any of claims 37 through 42, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry powder.

44. The dry processed film of a any of claims 37 through 43, wherein the active electrode material, the binder, the carbon nanotubes and the electrode composition are particulate materials.

45. The dry processed film of any of claims 37 through 44, wherein the active electrode material is a lithium transition metal compound.

46. The dry processed film of any of claims 37 through 45, wherein the active electrode material is graphite, a silicon-contammg compound, or any combination thereof.

47. The dry processed film of any of claims 37 through 46, wherein carbon nanotubes in the carbon nanotubes-polymer composite are present in amount of no greater than about 5 % by weight based on the total weight of the electrode composition.

48. The dry processed film of any of claims 37 through 47, wherein the carbon nanotubes in the caron nanotubes-polymer composite are the only fibrillating agent.

49. The dry processed film of any of claims 37 through 48, wherein the binder is a fibrillizable binder, a non-fibrillizable binder, or any combination thereof.

50. The dry processed film of any of claims 37 through 49, wherein the binder contains polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or any combination thereof.

51. The dry processed film of any of claims 37 through 50, wherein the binder includes a polymer that is the same or substantially the same as the polymer in the carbon nanotubes-polymer composite.Docket: 2022622PCT52. The dry processed film of any of claims 37 through 51, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.

53. The dry processed film of claim 52, wherein the PF AS polymer is PTFE.

54. The dry processed film of any of claims 37 through 51, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

55. The dry processed film of claim 54, wherein the PFAS-free polymer is PVP or HNBR.

56. The dry processed film of any of claims 37 through 55, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1:1 to about 100:0.1.

57. The method of any of claims 37 through 55, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10: 1 to about 100:0.1.

58. The dry processed film of any of claims 37 through 57, wherein the film is free-standing and has a thickness within a range of from about 30 to about 500 microns.

59. The dry processed film of claim 58, wherein the film has a tensile strength of at least about 0.1 MPa and / or an elastic modulus no greater than about 1000 MPa.

60. An electrode comprising the dry processed film of any of claims 37 through 59.

61. The electrode of claim 60, wherein the dry processed film is applied to a substrate.

62. A battery comprising the electrode of claim 60 or claim 61.

63. A carbon nanotubes-polymer composite, comprising:Docket: 2022622PCTa plurality’ of multi-walled carbon nanotubes; and aa polymer,wherein the carbon nanotubes-polymer composite is in pellet form and has a weight loss of 5% or less upon screening the carbon nanotubes-polymer composite through a 20-mesh sieve with 840 micron openings.

64. The carbon nanotubes-polymer composite of claim 63, wherein the composite has a weight loss of 3% or less upon screening the carbon nanotubes-polymer composite through a 20-mesh sieve with 840 micron openings.

65. The carbon nanotubes-polymer composite of claim 63, wherein the composite has a weight loss of 1% or less upon screening the carbon nanotubes-polymer composite through a 20-mesh sieve with 840 micron openings.

66. The carbon nanotubes-polymer composite of any of claims 63 through 65, wherein the carbon nanotubes have a BET within a range of from about 80 to about 500 m2 / g.

67. The carbon nanotubes-polymer composite of any of claims 63 through 66, wherein carbon nanotubes in the carbon nanotubes-polymer composite have a diameter within a range from about 2 to about 50 nanometers.

68. The carbon nanotubes-polymer composite of any of claims 63 through 67, wherein carbon nanotubes in the carbon nanotubes-polymer composite have an average particle size (Dso) within a range of from about 5 to about 500 microns, as determined by laser diffraction analysis.

69. The carbon nanotubes-polymer composite of any of claims 63 through 68, wherein the carbon nanotubes in the carbon nanotubes-polymer composite are pre-milled as a dry’ powder.

70. The carbon nanotubes-polymer composite of any of claims 63 through 69, wherein the carbon nanotubes-polymer composite contains a PF AS polymer.Docket: 2022622PCT71. The carbon nanotubes-polymer composite of any of claims 63 through 70, wherein the carbon nanotubes-polymer composite contains a PFAS-free polymer.

72. The carbon nanotubes-polymer composite of any of claims 63 through 71, wherein the weight % ratio of carbon nanotubes in the composite to the polymer in the composite is from about 1: 1 to about 100: 0, 1.

73. The carbon nanotubes-polymer composite of any of claims 63 through 71, wherein the weight % ratio of the carbon nanotubes in the composite to the polymer in the composite is from about 10: 1 to about 100:0.1.

74. A dry processed film comprising: an active electrode material, a processed binder, and the carbon nanotubes-polymer composite of any of claims 63 through 72.

75. An electrode comprising the dry processed film of claim 74.

76. A battery comprising the electrode of claim 75.

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