Electrode manufacture using fibrillated wet electrode slurry

Abstract

Wet electrode application techniques used for electrical energy storage devices use toxic solvents that are challenging to work with and difficult to remove. In wet-coating methods the binder partly covers active particles, limiting device performance. Dry electrode film forming techniques are associated with challenging manufacturing. Herein, a partially to fully fibrillated wet electrode or electrolyte application process involves mixing active material with a binder and optionally a conductive additive, partially to fully fibrillating the mixture, then adding a liquid, such as water to form a slurry. The slurry is coated on a current collector or electrode assembly, dried, and then roll-pressed. Optionally, the fibrillated wet mixture is adhered to the substrate, then wound into a jelly roll for the manufacture of an electrical energy storage device. A partially to fully fibrillated wet electrolyte coating may be adhered to a fibrillated wet, or dried, electrode film current collector assembly.

Description

ELECTRODE MANUFACTURE USING FIBRILLATED WET ELECTRODE SLURRYTECHNICAL FIELD

[0001] This application relates to energy storage devices, particularly to compositions of and methods for manufacturing electrodes for electrical energy storage devices.BACKGROUND

[0002] Energy storage devices may include primary and secondary batteries, capacitors, supercapacitors, and capacitor-battery hybrids, for example. Such an electrical energy storage device has a positive electrode (i.e. a cathode), a negative electrode (i.e. an anode), a separator and electrolyte. An electrode (i.e. anode or cathode) may have a metallic foil current collector applied with an electrode material layer on one or both sides. The electrodes may be wound, stacked or otherwise assembled with intervening separators into a device, a wound device generally being referred to as a jelly roll cell, which is inserted into a cell container known as a can and then saturated with an electrolyte, though many other assembly configurations may be utilized.

[0003] Traditionally, for energy storage device manufacturing methods the electrode layer is applied to the foil as a slurry, and is typically called a wet electrode application process. Additionally, the majority of slurry processes also involve the use of solvents, which tend to be toxic, costly and flammable.

[0004] More recently, electrode layers are being applied to foils as dry electrode films. However, current methods of producing dry films for electrodes are associated with problems, such as weak films with low mechanical strength, and with undesired thickness, creating challenges to complete the assembly process for the electrodes and the completed energy storage devices. Moreover, producing dry films typically demands sophisticated and precise equipment to achieve uniformity and proper layer formation.

[0005] U.S. Patent No. 10,923,295 to Raman et al. discloses an energy storage device that can include a cathode, an anode, and a separator between the cathode and the anode, in which the anode and / or electrode includes an electrode film having a super-fibrillated binder material and carbon. The electrode film can have a reduced quantity of the binder material while maintaining desired mechanical and / or electricalproperties. Increasing fibrillating of the binder material may facilitate formation of thinner electrode films, such as dry electrode films. This dry electrode approach requires deformable polytetrafluoroethylene (PTFE) binders with considerable plasticity, which can form fibers under shear force to connect electrode particles. The manufacturing processes include dry blending, dry fibrillating, dry feeding, dry compacting / calendering and bonding to the collectors, which exhibit compatibility with the roll-to-roll production line.

[0006] US Patent Application US2024 / 0178399 to Falzone et al. describes a binder powder for an electrochemical device, containing a non-fibrillated fibrillatable resin and a thermoplastic polymer.

[0007] This background is not intended, nor should it be construed, to constitute prior art against the present invention.SUMMARY OF INVENTION

[0008] The present invention is directed to a partially to fully fibri Hated wet electrode system and method, a method and apparatus for forming the fibrillated wet electrode, and electrical energy storage devices made using fibrillated wet electrodes. A fibrillated wet electrode for use in an energy storage device may be prepared using a method which includes at least one type of active material and at least one type of binder that can be fibrillated.

[0009] In some embodiments, the powder mixture for the electrode may include at least one type of conductive additive. In some embodiments, the powder mixture may include at least one type of functional additive.

[0010] In exemplary embodiments, the active materials are at least one type of activated carbon. In exemplary embodiments, the active materials are at least one type of electrode active material typically used in electrochemical energy storage devices such as batteries. In additional exemplary embodiments, the active materials are at least one type of electrolyte material, wherein the system and method are used to produce a fibrillated wet electrolyte, which may then be partially or fully dried to produce a dried fibrillated electrolyte. In additional exemplary embodiments, the active materials include at least one type of electrode active material and at least one type of electrolyte material to produce a layered or homogeneous electrode assembly.

[0011] The active electrode material in the form of a powder mixture, which may contain additional additives or solvents, is subjected to a shear or pulverizing force in order to become partially (above 0% to 99%) fibrillated to fully 100% fibrillated. The partially to fully fibrillated mixture is then mixed with a liquid, which in some embodiments is water, either deionized or purified water, to produce a fibrillated wet mixture. The fibrillated wet mixture of active electrode materials is then applied to a current collector, which may include an optional primed current collector. Priming may include the addition of a binder or binders, a mixture of conductive additive or conductive additives, and optional liquid. In an exemplary embodiment the liquid for the binder and conductive mixture is water. The optionally primed current collector may have the fibrillated wet electrode mixture applied to it through conventional methods including a Microgravure™ coater and / or an injector system. In certain embodiments the current collector foil is moved under a doctor blade to evenly disperse the fibrillated wet electrode material that was deposited on and across the current collector to ensure desired thickness. Water-based slurries may sometimes exhibit poor wettability on current collector foils, leading to adhesion issues and non-uniform electrode coatings, thus priming a current collector foil may be necessary in some embodiments. After the fibrillated wet mixture is evenly coated on the current collector, it is passed through a drying oven(s), at the desired speed and temperature, to evaporate the liquid and obtain a dry, partially to fully fibrillated electrode. After passing through the drying ovens the partially to fully fibrillated, now dry, electrode and current collector are passed through a set of press rollers to press and / or calender the electrode, which may include heating the rollers. In certain embodiments the process involves further fibri Hating the electrode, and then affixing it to the current collector with the optional priming layer by means of the press rollers. Optionally the current collector may be double-sided and have a second fibrillated wet electrode film applied, pressed, and bound to the second side of the current collector foil by the same steps as described above, for the first side of the current collector. Optionally the described electrode assembly may have a fibrillated wet electrolyte film applied, pressed, and bound to one or more sides of the electrode assembly by the same method as described above, which may be deposited on or in one or more electrode or separator layers.

[0012] In exemplary embodiments, the current collector has a priming layer such as a conductive glue or treatment applied to ensure a strong adhesion with the partially to fully fibrillated wet electrode on the first and / or second side. In additional embodiments the partially to fully fibrillated wet electrode may be applied directly to the current collector without a pre-treatment to the current collector, which in certain additional embodiments may include an additive for better adhesion. Treatments for the current collector may include surface modification techniques which may include all physical and chemical methods including etching, and additional optional examples of anodizing, or changing the surface's microstructure, and may include solvent cleaning.

[0013] Optionally, the current collector with an attached partially to fully fibrillated wet / dry electrode assembly may comprise two or more laminated electrode sections and require a step of slicing through the partially to fully fibrillated wet / dry electrode(s) to the current collector in order to form two or more separate electrodes. The resulting electrodes may then be layered and wound together, or with another electrode, with intervening ion-permeable and / or electrically insulating separators, to form a jelly roll or alternative energy storage device assembly. The energy storage device assembly then forms the core of an energy storage device.

[0014] The particle size of the precursor material used to produce active electrode materials, which in the case of activated carbon may include coal, petroleum coke and biomass as a few non-limiting examples, has a significant effect on the ultimate energy storage device performance and fibrillated wet electrode. The active material, e.g. activated carbon, used for the fibrillated wet electrode, may optionally be made with a selected particle size range, and the particle size distribution may be checked and / or adjusted at one or more points during the process.

[0015] Energy storage devices such as batteries and supercapacitors as well as hybrid devices have complex manufacturing processes that have traditionally utilized toxic solvents, those skilled in the art referring to solvent based processes as wet electrode processes. Within the last few decades, researchers and companies have developed new techniques and technologies with the goal to move away from these toxic solvent based wet electrode methods. These new methods are designed to produce electrode films that are dry, or involve a small amount of liquid or additive, which are generally referred to by those skilled in the art as dry electrode processesthat produce freestanding films, and / or dry electrode films, and utilize these specific dry electrode production processes.

[0016] During the production of dry electrode films, active materials are combined with binders, a common dry electrode binder being PTFE. The active electrode material, for instance activated carbon, may be used to make a supercapacitor as one non-limiting example, and may additionally incorporate a conductive additive such as carbon black, as one non-limiting example, and is combined with PTFE and then undergoes a process to mix and combine the materials together. After this process, the mixture undergoes a process referred to by those skilled in the art as material fibrillation, which is a process that elongates the PTFE and creates partial to full fibers from the PTFE that interweave with the active materials and conductive additives. Once this fibrillated material is pressed together, generally with heated press rollers that affix and / or interconnect the PTFE to the activated carbon producing an electrode film, it may then be affixed to a current collector substrate. This substrate may be a foil, for example aluminum used in supercapacitors, in order to produce electrodes to be used in an energy storage device.

[0017] Those skilled in the art have utilized various methods to produce dry electrode materials and combinations that may be used to produce dry electrode films. A few non-limiting examples include auguring and mixing the material while subjecting the material to a shear force, and then pressing it into a film. Also, a more common method is using a jet mill to partially or fully fibri Hate the PTFE while interweaving and combining it with the active electrode material to produce a partially to fully fibrillated mixture that may then be pressed into a freestanding film.

[0018] When partially to fully fibrillated material is pressed into a film, many properties of the film will affect its mechanical strength and the final performance of the energy storage device. Typically, higher amounts of binder (PTFE) lead to stronger films, as well thicker films also tend to be mechanically stronger, though higher amounts of binder and thicker films tend to lead to poor electrochemical performance for energy storage devices. Inversely, high amounts of conductive particles and small electrode particles, as well as thinner films tend to result in films that are mechanically weaker and tend to be more prone to surface damage, though higher amounts of conductive material, varying particle sizes and thinner films tend to lead to increased electrochemical performance for energy storage devices. These conflicting featuresbetween producing mechanically strong dry electrode films and also producing dry electrode films with good electrochemical properties result in challenges in the manufacture of energy storage devices with dry electrode production processes.

[0019] The disclosed system and method builds on the understandings for producing dry electrode films, specifically the benefit of using fibrillization to partially or fully fibrillate the binder material, to produce a system and method that produces a more consistent and manufacturable electrode and energy storage device. This is accomplished by partially to fully fibrillating the electrode mixture and then processing this fi bri Hated mixture into a wet, slurry, or ink-type electrode material by incorporating a liquid, and then applying this wet electrode mixture to a substrate such as a current collector. The disclosed system and method allows for improvements over both traditional slurry methods and dry electrode freestanding film methods, by combining the benefits of both methods without having to deal with many of the negative aspects from each method.

[0020] Specifically, the benefits of traditional slurry methods, though not only limited to the following benefits, include the simple application process via applying the electrode slurry through injectors onto a current collector and then moving the current collector and slurry under and through a die or a doctor blade to evenly distribute the electrode slurry across the current collector. This application process offers many benefits including precise control of the electrode thickness. It also presents many disadvantages including the typical use of NMP (N-methylpyrrolidone), a toxic solvent, requiring complex and expensive solvent recovery and management systems, as well as using binders that provide negative effects to the electrochemical performance of energy storage devices, as well thicker electrodes tend to crack and peel from the current collector utilizing this method. Regardless of the solvent type, the binder generally covers active materials in the slurry-type coating methods, which leads to under-utilization of active materials due to decreased access of the electrolyte to the active material.

[0021] The benefits of the fibri Hated wet mixture disclosed herein include one or more of the following:- Unlike slurry-type methods where the binder forms a network and covers the surfaces of the active material particles, the fibrillated binders bridge and link the active material particles without covering them, leading to better control overporosity and density of the laminated electrodes. Moreover, the use of fibrillated binders eliminates the mass loading limitations associated with cracking issues occurring when thicker electrodes are obtained, and if minor cracking does occur during drying, the electrodes can self-heal when pressed with the heated rollers.- The method uses a water-based slurry, whereas the majority of slurry-type methods involve a toxic solvent such as NMP, though this is not excluded in potential embodiments of the disclosure which may benefit by allowing better accessibility of the active electrode materials by optimizing binder types in one non-limiting example.- Fibrillated mixture in the dry form usually has poor processability because it is prone to severe clumping. Mechanical shredding in the dry form of the fibrillated mixture sometimes causes breakage of the fibers and leads to a weaker dry film. However, mixing the fibrillated mixture in a liquid such as water allows for processing of the slurry with significantly less damage to the partially to fully fibrillated binders.- Scale-up of manufacturing requires a fast-drying process using ovens for the slurry-type methods. When a thickly coated slurry is dried quickly, it creates a liquid density gradient between the surface of the film and the lower layers. This is because the surface dries much faster than the lower layers when exposed to heat, which causes cracks and structural integrity issues. However, the presence of fibrillated binder, as disclosed in the present invention, helps mitigate this liquid density gradient issue for thick coatings because fibrillated binders hold particles together in a three-dimensional structure, ensuring structural stability and a more flexible electrode with elasticity. Moreover, the subsequent process of hot-pressing the fibrillated electrode may enhance the structural integrity of the electrode, because the fibrillated binders soften and create better adhesion upon pressure, which may also repair imperfections that may appear.

[0022] The benefits for producing electrodes via a dry electrode free-standing film production process, though not limited to the following benefits, include the removal of solvents in the production of electrodes, which require complex solvent recovery systems for toxic solvents and the use of binders that can be fibrillated that offerexcellent electrochemical performance. Major challenges exist for producing dry electrode films, including the main challenge being the low mechanical strength of dry electrode films, which results from many factors including the films' thinness, typically about 1 / 1 Oth of a millimeter. Another challenge is the narrow range of percentages for acceptable binder(s), conductive additive(s) and active electrode material(s) to produce free-standing films strong enough to be mechanically usable, which in turn reduces electrochemical performance.

[0023] The disclosed system and method provide a form of partially to fully fi bri Hated binder and slurry that offer several advantages, which include elimination of toxic solvents such as NMP from traditional, solvent-based slurry coating methods, though these are not excluded as possible embodiments of this disclosure, by substituting water as an advantageous liquid instead of the solvent. Additionally, the disclosed system and method improves the application of the electrode to the current collector by using an advanced injection and coating method that remove the challenges with producing, handling, and affixing a thin and typically weak dry electrode freestanding film to the current collector.

[0024] In certain embodiments, the binder may be a dispersion of binder particles which may include nanoparticles, which may be in water, as a non-limiting example. In other embodiments, the binder is in particle form for instance 100nm to 1000pm, such as starting particle size of 500pm, and is, for example, PTFE. In certain embodiments, when using finer particles of a binder material, such as a dispersion of binder particles in water, the step of fibrillating the powder mixture may be eliminated.

[0025] Disclosed herein is a method for manufacturing a conductive layered assembly for an energy storage device, the method comprising the steps of: providing a mixture comprising a powdered active material, conductive additive, and fibrillatable binder, and optional additives, partially to fully fibrillating the material mixture; mixing the partially to fully fi bril lated mixture with a liquid to form a slurry with one or more optional functional additives, applying the slurry to a substrate comprising a conductive foil; drying the slurry on the substrate; pressing / calendering the layered assembly to form the conductive layered assembly.

[0026] Also disclosed is a method for manufacturing a conductive layered assembly for an energy storage device, the method comprising the steps of: mixing dry, powdered active material with a binder to form a mixture; fibrillating the mixture toobtain a partially to fully fi bril lated mixture; mixing the partially to fully fibril lated mixture with a liquid to form a slurry; applying the slurry to a substrate comprising a conductive foil; and drying the slurry on the substrate to form the conductive layered assembly.

[0027] Also disclosed is a conductive layered assembly made by: mixing dry, powdered active material with a binder to form a mixture; fibril lati ng the mixture to obtain a partially to fully fi bril lated mixture; mixing the partially to fully fibril lated mixture with a liquid to form a slurry; applying the slurry to a substrate comprising a conductive foil; and drying the slurry on the substrate to form the conductive layered assembly.

[0028] This summary provides a simplified, non-exhaustive introduction to some aspects of the invention, without delineating the scope of the invention.BRIEF DESCRIPTION OF DRAWINGS

[0029] The following drawings illustrate embodiments of the invention and should not be construed as restricting the scope of the invention in any way.

[0030] FIG. 1 is a flowchart showing the main steps of a process for making an electrode assembly or electrolyte assembly, according to an embodiment of the present invention.

[0031] FIG. 2 is a schematic drawing showing active material bound and coated with non-fibrillated binder typically produced with ink type methods that reduce accessibility of the active materials.

[0032] FIG. 3 is a schematic drawing showing active material bound with fibrillated binder using a fibrillated wet electrode method, according to an embodiment of the present invention.

[0033] FIG. 4 is a schematic drawing of apparatus for making an electrode assembly with sandwiched electrodes and electrolyte layers typically used in solid-state batteries, according to an embodiment of the present invention.

[0034] FIG. 5 is a schematic drawing of apparatus as an alternative embodiment for making an electrode assembly with electrodes and electrolyte layers typically used in solid-state batteries, according to another embodiment of the present invention.

[0035] FIG. 6 is a method for making a spooled electrolyte or electrode layer, according to an embodiment of the present invention.

[0036] FIG. 7 is a schematic drawing of apparatus for making a spooled electrolyte layer or electrode, according to an embodiment of the present invention.

[0037] FIG. 8 is a flowchart of a process for manufacturing an electrical energy storage device with the fibri Hated wet electrode material, according to an embodiment of the present invention.

[0038] FIG. 9 is a schematic cross-section of a portion of a laminated electrode with fibrillated wet electrode material, according to an embodiment of the present invention.

[0039] FIG. 10 is a flowchart for making a combined electrode and electrolyte film, according to an embodiment of the present invention.

[0040] FIG. 11 is a flowchart for making a sandwiched two-electrode electrolyte film, according to an embodiment of the present invention.

[0041] FIGS. 12 and 13 are scanning electron microscopy (SEM) images of a partially fibrillated mixture, according to an embodiment of the present invention.

[0042] FIG. 14 is an SEM image of a fibrillated wet electrode after being hot-pressed, according to an embodiment of the present invention.

[0043] FIG. 15 is an SEM image of a water-based ink-type electrode.

[0044] FIGS. 16 and 17 are SEM images of a fibrillated wet electrode before and after being hot-pressed, according to an embodiment of the present invention.

[0045] FIGS. 18 and 19 are optical images of a fibrillated wet electrode before and after being hot-pressed, according to an embodiment of the present invention.

[0046] FIG. 20 is an optical image of cracks in a typical water-based slurry-type electrode that has a non-fibrillated PTFE nanoparticle binder.

[0047] FIG. 21 is an optical image of a thin water-based slurry-type electrode that has a non-fibrillated PTFE nanoparticle binder.

[0048] FIG. 22 is an image of the electrode in FIG. 21 after being hot-pressed and gently touched.

[0049] FIG. 23 is an SEM image of the electrode of FIG. 22, showing micro cracks.DESCRIPTIONA. Glossary

[0050] Active material: the main active material used in making electrodes. The active material may be different depending on the type of energy storage device.

[0051] Additive: an additive used either in the production of the electrode or for improving the performance of the energy storage device and / or wherein the additives are added to the fibrillated mixture slurry to improve the stability, consistency, andviscosity of the slurry and enhance slurry adhesion to the substrate; wherein the additives may be one or more of different functional materials such as a binder, stabilizer, wetting agent, and surfactant, and are optional. The additive may be a conductive additive or functional additive.

[0052] Anode: when used herein in relation to an electrical energy storage device, this refers to the negative electrode.

[0053] Cathode: when used herein in relation to an electrical energy storage device, this refers to the positive electrode.

[0054] Compacted mixture: fi bri Hated or partially fibrillated mixture obtained when the powder mixture undergoes mechanical mixing or pressing, resulting in a dough-like or sheet like mixture rather than fluffy mixture.

[0055] Conductive additive: an additive used to increase the electronic conductivity of the active material and / or electrode, and is optional.

[0056] Dry film - a film obtained by a dry method, and / or solvent-free method, which can be used as an electrode of an energy storage device (dry electrode film) or as a dry electrolyte of an energy storage device depending on its material composition.

[0057] Electrolyte: a component of the energy storage device that connects the anode and cathode ionically.

[0058] Electrolyte material: the main active material used in a solid-state or semisolid-state electrolyte. For example, it may be an inorganic electrolyte or polymer electrolyte or a combination of them.

[0059] ESR: electrical equivalent series resistance calculated by using the potential drop in a constant current discharge curve of an energy storage device.

[0060] Fibrillated mixture: the powder mixture that has undergone a fi brillati ng process that may fi bri Hate the material or break it down into the desired size range, from pre-fi bri Hated deformed to partially fibrillated to the extent of fully fibrillated.

[0061] Fibrillated wet electrode slurry: the pre-fibrillated deformed to partially to fully fibrillated powder mixture that has undergone a process to combine it with a liquid, for example water, which mixes it together as a slurry. It is then applied to a current collector or other suitable substrate to form an electrode assembly.

[0062] Fibrillator: a machine that converts fibrillatable binder(s) into fibers, smaller particles, stretches or deforms the binder material, forming a pre-fibrillated deformed to fibrillated or partially fibrillated material. Non-limiting examples may include crushingand shearing machines, blending machines, fibrillating machines, feeding machines, extruding machines, heated or unheated roller press machines, auger mixing machines, compacting / calendering machines, air mills, and jet mill machines as a few non-limiting examples.

[0063] Foil, or current collector foil: an electrically conductive substrate or foil that facilitates the transfer of charge from / to electrodes. Electrodes are coated or bonded to the foil making a laminated electrode.

[0064] Fully fibril lated: wherein fibers have been extensively split or frayed into many smaller, fibers, and hair-like strands, binder particles have been subjected to a mechanical process resulting in their elongation forming fibrils. Even when a material is fully fibrillated, it may undergo further fibrillation, e.g. by converting larger fibers into smaller fibers or further elongating / stretching the fibrils.

[0065] Laminated electrode or electrode assembly: a layered structure of a current collector foil combined with a film or dried active material slurry on one or both surfaces of the current collector.

[0066] Partial fibrillation: some but not all of the binder particles are transformed into fibrils. Partially fibrillated refers to binder particles that have been split, frayed, deformed, or elongated to some extent but not as extensively as fully fibrillated fibers. In this state, the fibers exhibit some degree of splitting into smaller strands, but they retain more of their original structure compared to fully fibrillated fibers

[0067] Powder mixture: active material which may include additives (conductive additives, functional additives, etc.) and binder(s).

[0068] SEM: Scanning electron microscopy

[0069] Separator: an ion-permeable and electrically insulating separator. It is not electrically conductive, but it has pores to allow ions to pass through.

[0070] Slitting: cutting a laminated electrode to the desired width or splitting a laminated electrode into two or more electrodes.B. Exemplary Embodiments

[0071] The key steps of an exemplary method are shown in FIG. 1. In step 1 , combine and mix the dry powdered active material with fibrillatable binder(s) and optional additive(s) to form a powder mixture. In step 2, fibril late the mixture to form a pre-fi bril lated / partial ly / fully fibrillated mixture. The dry, partially to fully fibrillated mixtureis a mixture of a powdered active material and a binder that has undergone pulverization, impact, shear, or fibrillation after mixing. Other additives may be present, such as a conductive additive(s). In step 4, water and or another / alternative liquid along with optional functional additives are added to the fi bril lated mixture and mixed to make a homogeneous slurry. The liquid is not a solvent for the active material or the binder. In step 6, the slurry is spread or otherwise applied to a substrate, such as a conductive foil or electrode assembly that includes a conductive foil. In step 8, the substrate with the applied slurry is dried. In step 9, the electrode assembly is pressed / calendered to form a conductive layer assembly for use in making an electrical energy storage device.B1. Bound Material Structure

[0072] FIGS. 2 and 3 show the difference in results between the wet and fibrillated wet electrode methods, i.e. use of non-fibril lated binder and partially to fully fibrillated binder respectively. In the case of non-fibrillated binder 10 in FIG. 2, relatively large portions of the surface area of the active particles 12 are coated with the binder. Optional conductive additive particles 14 are also shown. In the case of fibrillated binder 16 in FIG. 3, the active particles 18 are held together with strands of the binder, and a relatively smaller portion of the surface area of the particles is covered. Optional conductive additive particles 14 are also shown. This figure applies to the dry electrode method and the fibrillated wet electrode method described herein.B2. Fibrillated Wet Mixture

[0073] In embodiments of the system and method as described the electrode assembly may be prepared as part of a roll-to-roll process. As a non-limiting example, the system may include at least one fibrillation unit, in which the active electrode mixture is partially to fully fibrillated. The fibrillated mixture may be mixed by a mixing unit with a liquid to form a fibrillated wet mixture, which may then be coated on a current collector by an injection unit and spreading unit. Subsequently, the coated collector may be dried with an oven or drying unit. Next the electrode coated current collector may be conveyed to a heated roll press unit where it may be pressed / calendered, followed by spooling in a spooling unit. The spooling process may include one or a plurality of tensioners and one or a plurality of alignment rollers tocontrol the spooling. In certain embodiments, the described process may be completed again on the second or opposing side of the current collector to produce a dual-sided, electrode-coated current collector.

[0074] Exemplified embodiments of the system and method to prepare the electrode assembly may be part of a roll-to-roll process. As a non-limiting example, the system may include one, two or a plurality of fibrillation units and fibrillated wet electrode mixers, electrode material injectors, doctor blades or dies, and roll press units, in which the partially to fully fibrillated mixture is formed into an electrode coating or coatings. In an exemplified embodiment, in which the fibrillated wet electrode is prepared, the fibrillated wet electrode is conveyed from the injector and coating machine to a drying unit or oven. From there, it is moved to the heated roll press unit, where it undergoes pressing / calendering, which may fibrillate or further fibrillate the mixture, and then may then be conveyed to a plurality of roll press units to successively reduce the thickness of the electrode, which may also fibrillate it further, commonly referred to as calendering. Subsequently, it is directed to a spooling unit, via spools, and through one or more tensioners and / or alignment rollers.

[0075] A fibrillated wet electrode for use in an energy storage device may be prepared by creating a powder mixture and incorporating at least one type of binder capable of fibrillation. In exemplary embodiments, the powder mixture includes at least one type of activated carbon material. In exemplary embodiments, the powder mixture may include at least one type of electrode active material. In additional exemplary embodiments, the powder mixture may include at least one type of electrolyte material. In additional exemplary embodiments, the powder mixture may include at least one type of conductive material. In additional exemplary embodiments, the powder mixture may include at least one type of optional additive material.

[0076] In an embodiment, the powder mixture is subjected to a pulverization, impact, or shear force, the powder mixture then being mixed with water or alternative liquid(s). In additional exemplary embodiments, the fibrillated wet mixture may include at least one type of functional additive material. The mixture may then be coated onto a current collector, which may include being coated on one both sides of the current collector. In certain embodiments, a fibrillated electrolyte film may be laminated onto or into a second or third film. In certain embodiments, a fibrillated wet electrolyte mixture may be coated onto or into one or more electrode assemblies.

[0077] In some embodiments, the mixture comprises by weight: 60-99% of the powdered active material; 1-15% of the binder; 0-5% of functional additives; and 0- 20% of a conductive additive. In some embodiments, the mixture comprises, by weight: 60-99% of the powdered active material; 1-15% of the partially to fully fibrillated binder; 0-5% of functional additives; and 0-20% of a conductive additive having a particle size between 1nm and 1 pm. In some embodiments, the mixture comprises, by weight: 75-97% of powdered active material, wherein the powdered active material is activated carbon; 3-15% of the binder; 0-5% of functional additives; and 0-5% of a conductive additive. In some embodiments, the mixture comprises, by weight: 60-98% of the powdered active material, wherein the powdered active material is battery material; 1-10% of the binder; 0-5% of functional additives; 1-20% of a conductive additive; and 0-5% of electrolyte material. In some embodiments, the mixture comprises, by weight: 85-99% of the powdered active material, wherein the powdered active material is electrolyte material; 1-10% of the binder; 0-5% of functional additives.B3. Method of Making an Electrolyte Layer

[0078] This method may include preparing a powder mixture including at least one type of electrolyte material, which may be an electrolyte salt, and at least one binder that can be fibrillated by undergoing a shearing process.

[0079] In exemplified embodiments of the present disclosure is a method for manufacturing an electrolyte layer which may be used in a non-limiting example(s) of a primary cell, secondary cell, solid-state battery or semi-solid-state battery. In certain embodiments, the method may include producing a solid-state dry electrolyte energy storage device. In certain embodiments, the method may include a scattering technique with controlled particle size, distribution, vibration and doctor blade to deposit the dry electrolyte on an electrode. In certain embodiments, most of the powder mixture may include one or a plurality of electrolyte material(s) and may include optional additives, as measured by weight. For example, 70% of the weight of the powder mixture or more, such as 80-95% or 80-99%, or preferably 90-99% is electrolyte material to achieve better electrochemical performance. In certain embodiments, the electrolyte powder mixture undergoes partial to full fibrillation by being subjected to a pulverization, impact, or shear force, and then undergoes additional mixing with a liquid such as water to form a fibrillated wet electrolyte mixture.This wet electrolyte mixture is applied to an electrode, and / or backing material and / or separator and dried, and optionally the assembly is pressed / calendered. Those skilled in the art will recognize the final electrolyte layer as a dry or semi-dry electrolyte layer.

[0080] Referring to FIG. 4, an apparatus is shown for making an electrolyte layer assembly, which may be useful to make as a non-limiting example a solid-state battery pouch cell. It shows a procedure for wet coating of fibrillated electrode and electrolyte layers for solid-state devices. The wet electrode fabrication process comprises several critical stages for preparing electrodes suitable for diverse applications, including batteries, capacitors, and sensors. Initially, a slurry is formulated by blending active electrode materials, conductive additives, which may include a non-fibrillated to partially to fully fibrillated binder(s) in a liquid. The use of optional binders, surfactants, and stabilizers is also considered. A layer-by-layer technique is used to laminate anode, cathode and solid electrolyte layers together. A thin layer of electrolyte, a cathode-electrolyte layer, is coated on the cathode. A thin layer of electrolyte is coated on the anode. Then, both are laminated together using a hot press to make sure both electrolyte layers merge into each other. In certain embodiments the anode and cathode compositions may include the electrolyte material. This may be used as a non-limiting example to increase the accessibility of the electrolyte material to the electrode material, and or decrease the interface resistance of the electrode and solid- state electrolyte.

[0081] A metallic foil 50, such as aluminum is coated with a cathode slurry 54 from hopper 52 with stirrer 53. The slurry may be a pre-prepared cathode suspension. This slurry is uniformly coated as a layer 56 onto the conductive substrate using precision techniques such as doctor-blade coating. The coated substrate then undergoes liquid removal within an oven 58. The resulting dried electrode film is guided through a hot roller press 60 and thereby calendered to achieve optimal density. Next, the electrolyte slurry 64 from hopper 62 with stirrer 63 is coated as a layer 66 on top of the cathode film, progressing through an oven 68 for drying and heated rollers 70 for optional calendering to form an electrolyte film 72.

[0082] Another metallic foil 74 is coated with an anode slurry 78 from hopper 76 with stirrer 77. The slurry may be a pre-prepared anode suspension. This slurry is uniformly coated as a layer 80 onto the conductive substrate, for instance copper, using precision techniques such as doctor-blade coating. The coated substrate thenundergoes liquid removal within an oven 82. The resulting dried electrode film is guided through a hot roller press 84 and thereby calendered to achieve optimal density. Next, the electrolyte slurry 88 from hopper 86 with stirrer 87 is coated as a layer 90 on top of the anode film, progressing through an oven 92 for drying and heated rollers 94 for optional calendering to form an electrolyte film 96.

[0083] Lastly, both the cathode-electrolyte layer 72 and the anode-electrolyte layer 96 are laminated together using a hot press roll 98. The two electrolyte films are laminated together using a hot roll press to make sure both electrolyte layers merge into each other, forming a collector-electrode-electrolyte layered assembly 100. This electrode-electrolyte sandwiched layer is then cut to the desired dimensions and may undergo further processes before integration into a final device. In certain embodiments a single electrolyte layer is used. In additional embodiments, for multilayer assemblies, the steps 52 to 70 for applying the electrode 56 and electrolyte 66 to the current collector 50 may be repeated on both sides of the current collector 50. In additional embodiments, for multilayer assemblies, the steps 76 to 94 for applying the electrode 80 and electrolyte 90 to the current collector 74 may be repeated on both sides of the current collector 74.

[0084] Referring to FIG. 5, in another embodiment, the electrolyte film 72 is coated with another electrode slurry 102 prepared in hopper 101 with stirrer 103. This other slurry may be a pre-prepared anode suspension if the electrolyte film has a cathode, and vice versa. This slurry is uniformly coated as a layer 104 onto the substrate using precision techniques such as doctor-blade coating. The coated substrate then undergoes liquid removal within an oven 105. The resulting dried double-electrode electrolyte film is guided through a hot roller press 106 and thereby calendered to achieve optimal density. Downstream, another foil layer 107 is applied to the top of the dried anode layer and calendered by rollers 108 to result in the sandwiched assembly 109 with current collectors on the outside, an electrode on each inner side of the current collectors and an electrolyte in the middle. In additional embodiments, the steps may be repeated, and this layer-by-layer strategy may continue, to make multilayer assemblies.B4. Method of Making an Electrode

[0085] In embodiments of the present disclosure is a method for manufacturing a partially to fully fibri Hated wet electrode, which may be used in various applications including non-limiting examples such as a battery or supercapacitor. The method may comprise preparing a powder mixture including at least one type of electrode active material and at least one type of binder that can be partially to fully fi bri Hated by undergoing a pulverization, impact, or shear fibrillating process. In certain embodiments, the powder mixture includes at least one type of electrode active material and at least one type of electrolyte material. In certain embodiments the majority of the powder mixture may be the particulate electrode active material as measured by weight. For example, 70% of the weight of the powder mixture or more, such as 80-99%, or 85-99% is electrode active material. The powder mixture undergoes partial to full fibrillation by being subjected to a pulverization, impact, or shear force, followed by combining and mixing the partially to fully fibrillated material with a liquid such as water into a fibrillated wet electrode slurry.

[0086] In certain embodiments, the fibrillated mixture undergoes a mild hot rolling process to make sheets of dry fibrillated mixture, which may further fi brillate the mixture, and which may be blended before, or while, mixing with a solvent such as water. In certain embodiments, the heated roller temperature may be in a range of 40- 300°C. In certain embodiments, the thickness of the sheet after mild rolling is about 100pm-50mm.

[0087] The fibrillated wet electrode may be used for an anode or a cathode, which may have a thickness of 10pm to 500pm, preferably 50pm to 250pm for easier handling and improved performance of the final device. In an exemplary embodiment, current collectors formed typically of a metal with a thickness of 4pm to 100pm, for example 5-45pm, are fixed with the fibrillated wet electrode material to form an electrode assembly. In an exemplary embodiment, the electrode assembly may be either an anode or a cathode.

[0088] In exemplified embodiments, to form an energy storage cell, multiple layers of cathodes and anodes may be stacked in an alternating fashion with separator(s) disposed between the anodes and cathodes. In exemplary embodiments, to form an energy storage cell, multiple layers of cathode and anode may typically be arranged inan alternating fashion with two or more separator(s) disposed in between the anode and cathode and rolled into a cylindrical cell.

[0089] Briefly, and referring FIG. 6, the steps to produce a partially to fully fibrillated wet electrode in an exemplary process are shown.

[0090] In step 110, sort or produce the active electrode material (i.e. particulate active material) to be composed of particles substantially of the range 10 nm to 100 pm. This step is optional.

[0091] In step 112, mix with PTFE and / or alternative fibrillatable binder and / or a plurality of binders and optional conductive material such as carbon black.

[0092] In step 114, perform a partial to full fibrillation process by subjecting the mixture inclusive of a fibrillatable binder to a pulverization, impact, or shear fibri Hating process, for example with an air mill or jet mill, wherein certain parameters can affect fibrillation including feed material particle size and composition as well as temperature, properties of fibrillatable binder, gas flow rate, material feed rate, jet pressure, moisture, gas type and temperature. This is in contrast to traditional wet electrode processes that do not involve fibrillation of the binder, which is typically PVDF (polyvinylidene fluoride).

[0093] Optionally, the partially to fully fibrillated materials may be sorted for size in step 116. In certain embodiments this step would be used when making a strong, dry electrode.

[0094] In step 118, add to the fibrillated material a liquid such as water. In step 119, add an optional functional additive to the fibrillated material and liquid. Mix in step 120 to homogenize the fibrillated wet mixture after fibrillation, continuing to mix the fibrillated wet electrode mixture non-destructively to reduce clumps, to produce a homogenous uniform mixture of the desired thickness, which may also include a functional additive. This is in contrast to the dry electrode coating method, in which the fibrillated material is not mixed with a liquid or solvent. A specific de-clumping step 122 may be included, using a sieve, for example. Liquids such as NMP may be used other than water in some embodiments, which may benefit the performance of devices by allowing the use of fibrous binders such as PTFE and less alternative coating type dissolved binders such as PVDF, allowing better accessibility of electrolytes to the active materials of the device. However, NMP is a solvent typically for dissolving PVDF and is the most prevalent solvent used in the production of batteries. Also, a priority isto use less toxic and more environmentally friendly liquids. In other embodiments the liquid may be a solvent that includes one or a combination of any of ethanol, methanol, isopropyl alcohol, propanol and n-butanol, to name a few non-limiting examples.

[0095] Optionally, in step 124, apply a primer to a current collector or change the surface microstructure of a current collector or coat it with a binder or glue, which is preferably a conductive mixture, and then spread it uniformly to the desired thickness, width, and length.

[0096] In step 126, apply the partially to fully fibrillated wet electrode mixture to the current collector, e.g. using one or more injector(s), and then spread it uniformly in step 128 using a doctor blade to the desired thickness, width and length. This is in contrast to dry electrode processes, which do not make use of injector(s) and doctor blade(s) for administering the film, and in which instead a freestanding film is prepared and then is pressed to the foil.

[0097] In step 130, dry the partially to fully fibrillated wet electrode layer by passing the current collector that has an applied fibrillated wet electrode mixture layer through an oven or heating unit.

[0098] In step 132, adhere and press / calender the now dry fibrillated electrode layer coated on the current collector assembly by passing the current collector assembly into heated rollers of the heated roller press machine, which may further fibrillate the partially to fully fibrillated electrode material, which may be accomplished for each side individually or at the same time with both sides coated.

[0099] Repeat the calendering as required to reach the desired thickness, density, fibrillation percentage, and adherence strength for the dry fibrillated electrode assembly.

[0100] In step 134, spool the electrode assembly and ensure the assembly is spooled onto the spool at a high enough tension to ensure that the spool remains at the desired tension across the rollers and when spooled.

[0101] Repeat the required steps 124-134 for the second side of the current collector in an embodiment in which both sides of the current collector host an electrode and primer layer.B5. Particle Sorting

[0102] In certain embodiments, the active electrode materials (i.e. particulate active material) used to make the electrode for an energy storage device undergo one or more steps of sorting the particles. In certain embodiments, the active electrode material is comprised of particles, bonded particles or aggregates thereof of which the majority of their sizes range from 0.1 pm to 50 pm, or 0.5 pm to 40 pm, or 1 pm to 20 pm, or 2 pm to 10 pm. The sorted active electrode material is used to produce energy storage devices such as batteries (primary and secondary batteries), supercapacitors, and hybrid systems, and / or energy conversion devices, such as fuel cells. In some embodiments having active electrode material comprised of particles, joined particles, or aggregates, thereof of which the majority of their sizes range from 0.1 pm to 50 pm, or 0.5 pm to 40 pm, or 1 pm to 20 pm, or 2 pm to 10 pm, results in an electrode film that has superior electrochemical performance characteristics when assembled and used in an energy storage device.

[0103] Additionally, having sorted particles may additionally increase the quantity of fibers joining one or a plurality of particles to an adjacent particle or plurality of adjacent particles. The number of connected fibers each particle can accommodate is a direct result of the particle size. Smaller particles have less contacting area available to accommodate PTFE and / or alternative binder and / or a plurality of binders.

[0104] One will appreciate that when the fibrillated wet electrode material is dried in an oven and then is pressed by passing the material into compressing rollers, the partially to fully fibrillated PTFE and / or alternative binder and / or plurality of binders is forced into the larger particle cavities, and adjacent particles cavities, creating numerous binder linkages. These binder linkages per particle result in a better binding force between particles within the electrode, which results in a mechanically stronger electrode overall.

[0105] In addition to more fibers connecting particles, the compressing force and / or shear force of the heated rollers of the electrode press machine allows better adhesion of the PTFE and / or alternative binder and / or plurality of binders to each particle; this is typically done by pinching the particles together with a compressing force. Additionally, utilizing heat to further press, shear, and bind the PTFE and / or alternative binder and / or plurality of binders to the electrode particles by melting or softening, partially melting or making formable by heat, allows PTFE and / or alternative binder and / orplurality of binders to immerse within the electrode material cavities, affixing into or onto the electrode particles and current collector.

[0106] In certain embodiments, small particles less than 2 pm do not compress as easily as particles with the size range from 2 pm to 20 pm, and result in thicker electrodes when using the same roller pressure and roller gap distance for these smaller particles. For example, using similar conditions (temperature, gap, pressure, etc.), the sorted particles (particle cut) of the range of 2 pm to 10 pm produced a thinner electrode than the electrode produced by the original unsorted particles, which in certain embodiments may be preferred. Additionally, the electrodes produced with the sorted, small particles gave the thickest electrodes when compared to the other two samples, which in certain embodiments may be preferred.

[0107] When smaller particles are removed, the larger particles can compress more tightly together, which may be a result of the binder being deposited better into the electrode material, and may be the result of larger particles collapsing. These factors may result in thinner electrodes with better particle binding, leading to a stronger electrode mechanically, which in certain embodiments is preferred.

[0108] In certain embodiments, the step of sorting active electrode materials may be used to separate particles that are smaller than desired and may include sorting out any particles smaller than a specific size. This may include sorting out any particles from about 1nm up to 250pm in size and then removing the undesired particles from the active electrode materials used to make the fibril lated wet electrode mixture.

[0109] In certain embodiments, the process of sorting the particles includes sorting all of the particles to the desired particle size range. In certain embodiments, the sorting process of the particles includes sorting the particles to the desired particle size range with some particles remaining that are not the desired particle range. In certain embodiments, the sorting process of the particles includes sorting the particles to the desired particle size range with a portion of particles remaining that are not the desired particle range. In certain embodiments, a portion of the particles is sorted to reach the desired particle size range and a portion of the particles remain unsorted.

[0110] Particles may be formed to the desired size during initial processing and fabrication of the material, or alternatively particles may be subject to a combining process which may include binding or joining the particles together and mayadditionally include an additive or additives that results in forming smaller particles into larger particle assemblies.

[0111] Non-limiting examples of how to achieve a good active material by sorting the particles may include sorting the particles by means of a wet or a dry particle sorting process. For a non-limiting example, the dry particle sorting may utilize an air classifier or air classifying process. For a non-limiting example, for the wet particle sorting, the particles may be dispersed in a solution followed by a filtration step to separate smaller particles, followed by drying.

[0112] In certain embodiments, a first material with particles ranging in size from 10nm to 50pm may be used to produce the fibrillated wet electrode mixture.

[0113] In certain embodiments, one or more binders may be used. In certain embodiments, the process uses at least one fibrilliatable binder. In some embodiments the fibrillatable binder is PTFE. A given binder may require a different range of particle sizes to increase the mechanical strength and electrochemical performance of the film or slurry. This may be accomplished by utilizing particles that correlate the optimal diameter of the electrode particle size and the size of the binder fibrils once fibrillated. This can be explained further that the average length, in one non-limiting example of the fibrillated PTFE, may require a given particle size to integrate effectively into or onto the active electrode material, and the binder such as PTFE itself may have differing particle sizes leading to better integration and performance for a specific particle size or range.

[0114] The type of fibrillatable binder and the processing process will impact the diameter and length of the resulting fibers and the amount of fibers per particle. Fine- tuning these parameters allows control of the final characteristics of the fibrillated binder. Smaller particle sizes generally lead to finer diameter fibers. The Poisson ratio is the ratio of lateral contraction to longitudinal extension during stretching. The Poisson ratio of the binder can influence the mechanical properties of the fibers. Understanding the desired properties of the resulting fibers helps in selecting a binder with an appropriate Poisson ratio. The magnitude and duration of shear forces applied during fibrillation, heat, and the rate at which the mixture is fed into the fibrillator are critical. These forces can impact the degree of fibrillation and the final fiber characteristics. Optimizing shear forces based on the chosen binder type is crucial for achieving the desired results. Parameters such as temperature, pressure andprocessing time can significantly affect fibrillation. Varying these conditions while considering the type of binder may be useful to achieve the desired fiber properties and final fibril lated wet electrode mixture.

[0115] Depending on the type and morphology of the polymer binder, it can affect the electrical conductivity in at least two ways. In the case of a fibri Hated binder such as PTFE, the role of the binder here is to integrate particles tightly to provide good physical inter-particle contacts for electron transfer between particles. If the polymer forms a connecting lattice, it acts more as a glue to improve adhesion and / or create strong cohesion between the adjacent microparticles or nanoparticles and keeps particles attached together, which again improves the electron transfer. These kinds of binders are needed, for example, if we want to glue smaller particles into larger particles. For example, a binder can act as a glue for nanometer-size particles to aggregate them and form larger particles.

[0116] In additional embodiments, to achieve an active material with particles of the desired size, a process may be accomplished by aggregating and / or combining the particles. This combining and aggregating process is particularly useful for materials that have smaller particles that range in size down to nanometers. An additional embodiment may utilize a first nanoparticle-sized material, which then combines into a secondary material composed of particles that are micro-sized, from 0.1 pm to 50 pm, or 0.5 pm to 40 pm, or 1 pm to 20 pm, or 2 pm to 10 pm, and which may include a binder or a plurality of binders.

[0117] In certain embodiments, producing the particles of the desired range may be accomplished by means of adding functional additives in the material synthesis process. As a non-limiting example, a surfactant may be used while synthesizing materials typically used in batteries that will result in larger particles being formed. Additional non-limiting examples of functional additives used to make particles of the desired size may include ligands, surfactants, solvents and polymers.

[0118] The powder mixture is prepared by mechanically mixing its components, including at least one type of active material and at least one type of fibrillatable binder, and it optionally may include at least one type of conductive additive and at least one type of functional additive. In some embodiments a liquid such as a lubricant (e.g. a non-aqueous lubricant) or another liquid (e.g. water) may be added to the powdermixture. In additional embodiments a second, third, or plurality of additional binders may be used to stabilize the suspension of particles within the liquid.

[0119] Conductive additive with a smaller particle size, such as a non-limiting example of 1nm to 1 pm, may be added to the active electrode material to improve performance. The conductive additive may compose 0% to 20% by weight of the electrode material. In certain embodiments, a step of sorting or selecting particles may be performed on the conductive additive to produce the desired particle size for use in electrode material. In certain embodiments, the step of sorting the conductive particles may be performed during fibrillation or before fibrillation and may take place separately from the electrode material and fibrillation step or in a combination process.

[0120] The average particle size of typical commercial activated carbon is defined, for example, by: D10 1.9 (10% smaller than 1.9pm), D50 5.6 (50% smaller than 5.6pm), D90 9.7 (90% smaller than 9.7pm). The average particle size of the PTFE is typically 500pm. Other sizes and size distributions may be used in other embodiments.The amount of PTFE in the electrode layer mixture is in the range of 0.25% to 20%, ideally 1-15% by weight. Below this amount the resulting electrode layer becomes too weak to handle or remain uniform; above this amount, the resistance of the electrode increases to a high value. The percentage amount of PTFE to use depends on what is desired in terms of strength and thickness of the electrode, and depends on the type and density of active material, etc. For the activated carbon specified above, about 1- 20%, or about 2-15% PTFE by weight is preferred. In some embodiments, 1-10% PTFE by weight is used. For more dense materials, like battery active materials, less PTFE in the range 0.25-15% is preferred.

[0121] Optionally, one or more conductive additives (such as carbon black) may be included in the mixture, in an amount of 0-20% by weight. In some embodiments, the amount of conductive additive is 1-10%. The inclusion of a conductive additive reduces the resistance of the electrode. Above this amount, the percentage of activated carbon in the electrode is reduced enough to have a detrimental impact on the amount of charge that can be held in the electrode. The particle size of the carbon black is typically below 1 pm and down to nanometer dimensions.

[0122] The powder mixture may include, by weight 60-99% of active materials and 0- 20% of conductive additive and / or other functional additives and 0-10% of one or more binders. In an exemplary embodiment, the powder mixture may comprise 75-98%active materials, 2-15% binders, and 0-10% additives (conductive additive and / or other functional additives).

[0123] In exemplary embodiments, the binder may include a fibrillatable fluoropolymer. In some embodiments the electrode mixture may include between about 1% to 30% fluoropolymer particles by weight, or 2% to 20% fluoropolymer particles by weight, or 1% to 10% fluoropolymer particles by weight, or 2% to 9% fluoropolymer particles by weight, or 1-7% or about 9% fluoropolymer particles by weight.

[0124] In certain embodiments, the dry powder may include between about 80% to 95% of activated carbon and between about 0% to 15% of conductive additive, and the dry binder may include between about 1% to 15% fluoropolymer.

[0125] In certain embodiments, the method of manufacturing an electrode for use in an energy storage device includes the step of mixing dry carbon, dry binder particles and dry conductive particles to form a dry mixture. Thereafter, the method incudes partially to fully fibri Hating the dry mixture and mixing the dry mixture with a liquid such as water to form a partially to fully fibrillated wet mixture, which may then incorporate one or more functional additives, which is then formed onto a current collector to produce an electrode.

[0126] In certain embodiments, the method of manufacturing an electrode for use in an energy storage device includes the steps of mixing dry active material particles, dry binder particles, and conductive additive particles, followed by mixing the dry mixture, partially to fully fibri Hating the dry mixture, mixing and / or blending the fibrillated mixture with a liquid such as water with the addition of an additive. In certain embodiments, the additives may include any one or more additives selected from: acetates, alcohols, antifoaming agents, dispersion aids, water, glycols, hydrocarbons, high boiling point solvents, Isopar™ M, ketones, mineral spirits, naphtha, pyrrolidone, surfactants, toluene and xylene.

[0127] In certain embodiments the electrode may be used in an energy storage device and have a lithium-containing, non-aqueous electrolyte. In certain embodiments the electrode may be used in an energy storage device and have a lithium-containing hybrid electrolyte and / or salt-in-water electrolyte. In some embodiments, the electrode may be used in an energy storage device having an organic electrolyte. In certain embodiments, the electrode may be used in an energy storage device having anaqueous electrolyte. In certain embodiments, the electrode may be used in an energy storage device having an ionic liquid electrolyte. In certain embodiments, the electrode may be used in an energy storage device having an electrolyte with an ionic liquid and an organic solvent. In certain embodiments, the electrode may be used in an energy storage device having a dry-type electrolyte.

[0128] Referring to FIG. 7, a process and apparatus for manufacturing a fibrillated wet electrode material are shown. The starting active material 140 (a particulate active material), provided in hopper 141 , is sieved or cut to remove the smaller particles 142. The remaining, larger particles 143, i.e. the upper cut of the particulate active material, are used in the process.B6. Mixing

[0129] Still referring to FIG. 7, the starting materials 146, 150 as well as the mixed electrode mixture may be mixed in a mixer 152, for example, in order to disperse them homogenously to make the powder mixture. The mixer may be a vacuum mixer, which serves to keep the combined starting materials 154 or mixture dry, or to remove residual moisture from the materials. There is a wide range of possible stirring speeds, depending on the amount of material and the size of the mixing chamber. For example, the materials may be mixed with a stirrer 153 operating at a speed of between 20 and 50 rpm. Different stirring speeds may be used at different times during the mixing step. There may also be one or more dispersers 155 in the mixing chamber. There is a wide range of possible dispersion speeds, depending on the amount of material and the size of the mixing chamber. For example, the materials may be dispersed with a disperser operating at a speed of between 20 and 10,000 rpm. Different dispersion speeds may be used at different times during the mixing step. The running time of the mixer also has a wide range of possible durations. For example, the total running time of the mixer may be 50 minutes, 1 hour, 2 hours, up to 8 hours or more. This may be made up of a plurality of periods; for a non-limiting example: first, a 5-minute period during which the mixture is stirred at 20 rpm, without any dispersion; second, a 5--minute period during which the mixture is stirred at 35 rpm, without any dispersion; third, a 10- minute period during which the mixture is stirred at 50 rpm with the disperser operating at 500 rpm; fourth, a 10-minute period during which the mixture is stirred at 50 rpm with the disperser operating at 1000 rpm; fifth, a 20-minute period during which themixture is stirred at 20 rpm with the disperser operating at 20 rpm. In practice, the mixing time could be as short as a minute and as long as several days comprised of various mixing speeds.

[0130] The starting materials in certain embodiments, i.e. the activated carbon, the PTFE and the optional carbon black may be dried before being placed in the mixer 152, while they are in the mixer, or both. The resulting mixture may be further dried after removal from the mixer. Drying may involve vacuum drying, air drying or heating, or any combination of these. By drying the mixture, the likelihood of clumps forming is reduced, as well the process to partially to fully fi bril late the material may be improved, as well the likelihood of the mixture sticking in parts of the apparatus downstream of the mixer may be reduced. For example, the mixture may be dried for an hour after it has been mixed.B7. Fibrillation

[0131] In step 114 (FIG. 6), the powder mixture 158 (i.e. 154 after mixing) of active materials and binder is partially to fully fi brillated. It is sufficient to partially fibri Hate the mixture once, which in certain embodiments include pre-fibrillating the material. In certain embodiments prior or during fibrillation heating the fibrillatable material or mixture, heating the air used and / or the fibrillation device may be used, and may provide better fibrillation. In certain embodiments, the process of fibrillation is conducted in temperature range of 20°C to 300°C, in a range of 30°C to 100°C, or in a range of 50°C-80°C. Only the binder is partially to fully fi brillated , not the other components in the mixture, though multiple steps of fibrillation may be beneficial to further fibrillate or super-fibrillate the material such as in U.S. Patent No. 10,923,295. The mixture 154 may be transferred from the mixer 152 or other type of mixer to a hopper 156 above the fibrillator 160 via a stream of dry air under the pull of a vacuum, conveyed, or manually transferred. The mixer 152 and the hopper 156 above the fibrillator may be connected together in a closed loop, with one or more valves to seal one from the other when necessary or to control pressure differences. The rate at which the mixture is fed into the fibrillator, or the amount that is fed into the fibrillator in a batch, may be controlled to prevent an excess of the partially to fully fibrillated mixture building up and possibly clumping. The result of fibrillating is a partially to fully fibrillated mixture 161 that includes fibrils 162 of the PTFE or elongation and / ordeformation of the PTFE, sometimes referred to as pre-fibrillated material when partially fibri Hated.

[0132] The step of preparing the fibrillated mixture may comprise applying a pulverization, impact, or shear force, causing partial to full fibrillation. A gas system, such as one providing pressurized gas flow, may be used to subject the mixed powder to a pulverization, impact, or shear force. In an exemplary embodiment, air which may be dried may be used in the gas system for material transport and feeding within the machine as well as for air of jet mill fibrillation. The pressure of the gas flow applied to the mixed powder may be 345-690kPa (50-100 psi), or between 69kPa - 14Mpa (IQ- 2000 psi), which may include heated air.

[0133] A mechanical system may be used to subject the mixed powder to a pulverization, impact, or shear force, such as an auger or a mill, which may result in a dough-like partial to fully fibrillated mixture, which may be then mixed with a liquid. In some embodiments, the mixture may be heated during the shearing process. In some embodiments, a liquid or an additive may be used in the mechanical approach to facilitate the process. Before mixing with the active materials, the binder(s) may be partially to fully fibrillated by shear mixing in a liquid and / or with the help of a chemical system.

[0134] The structures of the powder mixing / blending unit, the shearing / fibrillating unit, roll press unit, calendering unit and additionally the lamination unit are generally known to those skilled in the art.

[0135] PTFE has multiple transition phases at different temperatures, for example there are different transition temperatures at about 19°C and then 30°C. At lower than 19°C, PTFE can be mixed while maintaining its shape and physical properties. In contrast, at higher than 19°C, the PTFE structure becomes weaker and more sensitive to mechanical shearing. At temperatures higher than 30°C significant fibrillation may occur. At temperatures higher than 60°C, typically significant fibrillation may occur. As the temperature increases, the fibrillation rate also has shown to increase. By fibrillating above 30°C, less time is needed for the fibrillation than if the temperature were lower than 30°C.B8. Slurry Formation

[0136] In step 118, water is added to the dry partially to fully fibrillated electrode mixture, as well as optional functional additive(s) in step 119 if required. A hopper 164 is filled with partially to fully fibrillated mixture 169, from the fibrillator 160. The material is then passed into a mixer 166 with a stirrer 168 and disperser 172, and water 165 is added. Other mixers may be used in other embodiments. In certain embodiments, 170g of the fibrillated electrode mixture may be mixed with 600ml of water; this is a ratio of 1g fibrillated material to 3.5ml of water. In certain embodiments, the slurry begins getting quite thick at about 200g of fibrillated electrode mixture to 600ml of water. In certain embodiments, the mixture range varies from an absolute maximum thickness of 1g of the fibrillated electrode mixture to 0.25ml of water, and as thin as 1g of the fibrillated electrode mixture to 20ml of water. In certain embodiments, a suitable narrower range of the ratio is from 1g fibrillated material to 10ml of water, or 1g of fibrillated material to 5ml of water, or 1g of fibrillated material to 3ml of water may be used. In certain embodiments, the water may be deionized or purified water. In certain embodiments, the partially to fully fibrillated electrode mixture may be made with lower quality water, even with tap water, without causing serious issues. However, this does introduce the possibility of contamination and side-reactions occurring in the energy storage device.

[0137] In step 120, continued mixing of the fibrillated wet electrode mixture 170 is beneficial to ensure all particles, especially smaller particles are mixed together with the larger particles forming a homogeneous fibrillated wet mixture. Mixing, for instance with a blender, results in the homogenous mixture. In certain embodiments, the mixing is accomplished by using a first starting liquid; in an exemplary embodiment this liquid is water. The partially to fully fibrillated electrode mixture is added to the liquid in a controlled blending process to allow the fibrillated electrode mixture to disperse into the liquid and form a uniform and consistent fibrillated wet electrode mixture. In certain embodiments heating the electrode mixture dispersed in the liquid while subjecting it to blending / shearing results in further formation of fibrils in the mixture. Examples of temperature ranges include 20°C to 130°C, for example 30°C to 90°C. Blending and shearing speed ranges may include 20-10,000 rpm, for example 1 ,000-8,000 rpm. In certain embodiments, additional binders, additives, and / or stabilizers, such as emulsifying agents may be used to increase the surface adhesion and / or wetting to thecurrent collector and may be used as an alternative to pre-priming the current collector, and or to stabilize the mixture. The liquid additive which may be used as a dispersion material or carrier and may be used to produce the additive solution may include an aqueous or non-aqueous additive, and non-limiting examples may include one or more of the following chemicals such as: acetone, an acetate ester, an alcohol, diethyl carbonate, dimethyl carbonate, ethanol, a glycol, a hydrocarbon, isopropanol, and particularly n-methyl-pyrrolidone as well as combinations. In alternative embodiments adding these or other additives to the mixture may be for one or both of the following purposes: 1 - for a more stable and homogenous dispersion; 2 - so that the mixture easily wets the substrate or primed substrate and makes for a good adhesion to it. The additive may be categorized into non-limiting examples of stabilizers, surfactant, wetting agents, all of which are considered polymers.

[0138] As well, emulsifying agents, such as additional binders, may be used to ensure that the fibril lated wet electrode mixture remains a consistent homogenous mixture for extended periods of time to provide a consistent working material over extended durations while applying the mixture to current collectors to form electrode assemblies.

[0139] Additional additives and stabilizers may include: acetates, alcohols, antifoaming agents, dispersion aids, water, glycols, hydrocarbons, high boiling point solvents, Isopar™ M solvent, ketones, mineral spirits, naphtha, pyrrolidone, surfactants, toluene and xylene adhesive polymer binder is selected from the group consisting of PVDF, polytetrafluoroethylene (PTFE), SBR (styrene butadiene rubber), PVA (polyvinyl alcohol), polyethylene oxide (PEO), polyacrylic acid (PAA), polyvinylpyrrolidone (PVP), polyvinyl acetate, casein, sodium alginate, guar gum, xanthan gum, polyethylene glycol (PEG), gelatin, gum arabic, gellan gum, chitosan, and mixtures thereof. The adhesive may also include one or more additives, such as a stabilizer, thickening or emulsifying agent. The thickening agent may comprise any one or a mixture of cellulose, cellulose-based water-soluble polymers. Non-limiting examples include carboxymethyl cellulose (CMC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), and sodium carboxymethyl cellulose (Na-CMC)

[0140] In certain embodiments, the additive may be 0.0%-10% by weight, and may be a polymeric compound, surfactant or viscous liquid; examples include mineral oil orwax, such as paraffin wax. These additives may act as a dispersant, for example to disperse carbon nanotubes, or as a binder. Examples may include materials described in U.S. Pat. No. 8,540,902, which provides specific examples of dispersants and polymeric binders such as thermoplastic polyester resin, polyethylene, polypropylene, polyamide, polyurethane, polyvinyl chloride, polyvinylidene fluoride, polyvinylpyrrolidone, polystyrene sulfonate, polyphenylacetylene, polymetaphenylenevinylene, polypyrrole, polypphenylene benzobisoxazole, natural polymers, amphiphilic materials in aqueous solutions, anionic aliphatic surfactant, cyclic lipopeptido bio surfactant, sodium dodecyl sulfate, water-soluble polymers, polyvinyl alcohol sodium dodecyl sulfate, polyoxyethylene surfactant, hydroxyl ethyl cellulose polyacrylic acid, polyvinyl chloride as non-limiting examples and may include one or more of the described or combinations thereof.

[0141] After mixing the dry partially to fully fibrillated electrode material with a liquid and prior to being fed into a wet electrode mixture applicating device, the material may optionally be put through a clump reducing process (homogenizer) in step 122 that does not damage the fibrils of the PTFE and / or alternative binder and / or plurality of binders, but reduces the average size of material being fed into the wet electrode mixture applicating device. The clump reducing device may be a vibratory sieve, for example.

[0142] The homogenized, partially to fully fibrillated wet mixture 174 is transferred to a hopper bin 176 for subsequent transfer of the fibrillated wet mixture to a substrate. In some embodiments, a pump is used to move the fibrillated wet mixture from the homogenizer to the hopper bin, or directly from the mixer to the hopper bin. In some embodiments, the hopper bin 176 may be replaced with the hopper bin 181 , which has an inlet 182 at the top and an outlet 183 at the bottom. In certain embodiments it may have a sloping wall 184 that may be vibrated, which may reduce the tendency of the fibrillated wet mixture to clump together and may also include a stirring or mixing assembly to ensure the fibrillated wet electrode mixture remains homogenous.

[0143] The rate at which the fibrillated wet mixture 174 is fed into the hopper bin, or the amount that is fed into the hopper bin in a batch, may be controlled to prevent an excess of the fibrillated wet mixture building up and possible clumping. Feeding of the fibrillated mixture may also be sequence-timed with a liquid type conveyor, for instance a pumping conveyor, to ensure that the feed rate is sequenced to ensure a reductionof build-up or separation time, which may cause packing or separation of the fibrillated wet electrode mixture and lead to clumping.

[0144] The homogenized, fibrillated wet mixture 174 in hopper 176 may be further de-clumped by sieving and optionally heated, for example, in order to control the particle size and viscosity of the fibrillated mixture. Clumping may be reduced by breaking the clumps into smaller clumps of an acceptable size or by removing them entirely. A sieve or other particle size sorting and separating device or machine is used to prevent larger particles or clumps of particles from reaching the subsequent stage of the process. In some embodiments, the larger clumps of the fibrillated wet mixture are broken down into smaller clumps, which for certain embodiments may include high speed blending of the fibrillated wet mixture. Benefits of the clump reducing process include an even, consistent film that has less likelihood of clumps forming and dragging along the surface of a current collector, damaging the electrode coating consistency. An even film is obtained for instance if a doctor blade, die or slot die, is used to apply the fibrillated wet electrode by spreading the mixture out through a dragging process.

[0145] One will appreciate the benefit of ensuring a consistent coating and or film throughout the entire film forming process, where inconsistencies may affect final cell performance and manufacturability of the electrode during cell assembly. This is especially the case for very thin coatings, and wherein producing a more energy-dense cell with lower electrode resistance requires minimizing the binder, reducing mechanical strength and adherence of the optional priming layer and fibrillated wet electrode.

[0146] One will appreciate that the improvements as described herein are not necessarily apparent as critical steps when testing at lab scale, for instance when producing coin cells, as the electrodes used for small scale testing are generally shorter in nature and typically are not being produced continuously, which is typically significantly more difficult to achieve.B9. Spreading

[0147] In step 126, the sieved (or de-clumped), fibrillated wet electrode mixture 174 is applied to form a layer 216 on a current collector, or more generally a substrate 214, and then dried.

[0148] Prior to spreading, the current collector may be primed. For example, binder, solvent or other priming substance 190 in bath 192 is applied with a roller 193 and doctor blade 194 onto a foil 195 unwound from spool 196. The current collector with a coat 198 of binder, solvent or other priming substance may then be dried or heat treated in oven 210 to result in a primed substrate 214. In another example, binder, solvent or other priming substance may be sprayed with nozzles to form a film on the current collector foil 195 as it is unwound from the spool.

[0149] Spreading the fibrillated wet electrode mixture is done by feeding the sieved, fibrillated wet electrode mixture 174 from a mixing chamber 177 with stirrer 178 onto the primed current collector 214 or other substrate, typically done using an applicating doctor blade 220 to evenly spread the fibrillated wet electrode mixture. In another embodiment, spreading the fibrillated wet electrode mixture is done by pumping the fibrillated wet electrode mixture through injector nozzles to form a stream or spray of the mixture onto the current collector or primed current collector, and then optionally and preferred, passing the sprayed current collector under a doctor blade to evenly spread the fibrillated wet electrode mixture. After the fibrillated wet electrode mixture is dried via drying ovens 222, the now dried electrode is passed into and through a heated dual roller press 226, 228 to adhere and calender the dried electrode, and then spooled.

[0150] Uniformly feeding the fibrillated wet electrode mixture 216 onto the current collector is important for obtaining a consistent final electrode. Clumping and gumming of feed material may cause a weaker electrode coating and / or negatively affect electrochemical performance of the energy storage device or may prevent material from being fed into the application doctor blade or injector system, causing incomplete or inconsistent areas of the electrode coating.B10. Calendering

[0151] In the roller press, dried partially to fully fibrillated mixture coated on the current collector is heated and compressed, which may introduce fibrillation or additional fibrillation, into a multilayer electrode assembly 240 between the two rollers. The heated rollers typically have a diameter of 30cm, in one example. Other diameters are also possible, such as between 10cm and 1m. The thickness of the multilayer electrode may be set by controlling: the rotation speed of the rollers 226, 228 whichaffects the residence time within the rollers; the temperature of the rollers; the width of the fibrillated wet electrode coating; the gap between the rollers; the force by which the rollers are maintained in position and therefore pressed against the multilayer electrode assembly as it is formed; as well as the contact distance of the heated rollers the multilayer electrode is pressed within to produce a dried fibrillated electrode coating of a certain width. For example, the temperature of the heated rollers is between 50°C and 300°C. Outside this range, the ESR may be increased, and strength reduced. Optimally, the range is 60°C to 140°C. In other embodiments, the range is 80°C to 140°C. Supplying the multilayer electrode more slowly to the heated rollers and increasing the dwell time (residence time) of the multilayer electrode assembly between the rollers results in a thinner dried fibrillated electrode coating, and can also result in a more consistent and stronger coating compared to faster feed rates and shorter dwell times, though a dwell time too long, or with too much pressure or heat, may cause deflection of the current collector. Additionally, the width of the desired multilayer electrode assembly will facilitate the amount of pressure applied to it by the heated rollers to the multilayer electrode assembly. A narrower width of multilayer electrode assembly results in more pressure directed and applied and therefore a thinner multilayer electrode assembly.

[0152] Depending on the embodiment, the parameter settings of the heated rollers is such that the dwell time of the multilayer electrode within the heated rollers is limited to a maximum of a few seconds, 30 seconds, a maximum of 60 seconds or a maximum of 5 minutes, for example. Beyond these times, the material risks having its quality reduced. By controlling the feed rate and the time for which the multilayer electrode is exposed to the heated rollers helps to prevent deflection of the current collector causing it to bend and flex resulting in a more challenging process during subsequent assembly steps for the energy storage device. In some embodiments, the multilayer electrode assembly may be heated and fed onto cold or unheated rollers. In this case the temperature range of the rollers is extended to include the range 10°C to 250°C, although a more suitable overall range is 60°C to 150°C. For example, the dual roller compression step may be a step of pressing the multilayer electrode assembly such that it has an average thickness of 10-1 , 000pm, or 20-500pm, or 30-170pm, or about 65pm-110pm, in exemplary embodiments.

[0153] In certain embodiments, the heated dual roll press unit may have a controllable roller temperature, and in these embodiments the roller temperature may be set to a temperature of 5-250°C. In additional embodiments, at least one of the roller(s), each independently, in the roller press unit, may have a temperature of 5- 250°C. Additionally, the multilayer electrodes assemblies active material density (resulting in energy storage device mass loading) may be controlled by reducing the gap between the rollers in the roll press unit, or by increasing or decreasing the speed ratio of the rollers, or any additional referenced parameters.

[0154] In certain embodiments, the compression and calendering of the multilayer electrode assembly may increase its mechanical strength and electrochemical performance and decrease its thickness.

[0155] After calendering, the resulting electrode assembly is pinched between pinching rollers 230, 232, tensioned with tensioning roller 234 and wound onto a spool 242.B11. Cell Manufacturing Process

[0156] Referring to FIG. 8, a flowchart shows steps of a process for manufacturing an electrical energy storage device with the fibrillated wet electrode material.

[0157] A typical manufacturing process for primary cells, secondary cells and supercapacitors can be broadly divided into an electrode fabrication step, an electrode layering or winding step, a cell assembly step, and a cell testing or aging step. The electrode fabrication step is further divided into a powder combining and mixing step; mixed powder partial to full fibrillation step to form a fibrillated mixture; a partial to full fibrillated mixture liquid incorporating and mixing step; a coating a current collector with a fibrillated wet mixture step; a step drying the fibrillated wet electrode coated current collector; a pressing and calendering the dried partial to full fibrillated electrode and current collector step, which may introduce or increase fibrillation; in certain embodiments an electrode assembly slitting step; in exemplary embodiments a second step of coating the opposing side of the current collector with the fibrillated wet electrode mixture, a second calendering of the dried fibrillated electrode and current collector for the opposing side; an electrode assembly slitting step; a layering or winding step to form the interior cell contents; a series of cell assembly steps; and a series of cell testing and / or aging steps, or the like.

[0158] In optional step 302, the aluminum or other suitable foil for the current collector is treated to remove potential contaminations or residual oils that may be present on its surface as a result of its manufacturing process. Such residual contaminations may be removed by heating the foil to 50°C-200°C until the contaminations have substantially evaporated or been displaced. In other cases, the residual contaminations may be removed by chemical treatment of the foil. In other cases, the residual contaminations may be removed by air or atmospheric plasma treatment of the foil. The foil may be heated by one or more hot rollers, for example, or by a radiant or convection heater. By removing the residual contaminations, the adhesive that is to be applied to the foil binds more consistently and reliably to it. In turn, this allows the electrode mixture to adhere more consistently and reliably to the foil. In certain embodiments the treatment may not be necessary as the current collector may be provided without residues or oils or contaminations on its surface. However, in some cases where there is no contamination present, treatment may still be beneficial to improve surface adhesion by altering the microstructure and / or roughness of the surface.

[0159] In step 304, in certain embodiments, one or a plurality priming layers of electrically conductive adhesive materials are applied to one or both sides of the foil, to a width that corresponds to within 0.1 pm, for example, of the desired width of the electrode. The application of one or more adhesive materials may be referred to as priming the foil. The conductive adhesive may comprise one or more types of adhesive polymers and additives (5 - 45 wt.%). In some embodiments, the adhesive polymer binder is selected from the group consisting of PVDF, polytetrafluoroethylene (PTFE), SBR (styrene butadiene rubber), PVA (polyvinyl alcohol), polyethylene oxide (PEO), polyacrylic acid (PAA), polyvinylpyrrolidone (PVP) casein, sodium alginate, guar gum, xanthan gum, polyethylene glycol (PEG), gelatin, gum arabic, gellan gum and admixtures thereof. The adhesive may also include one or more forms of conductive carbon materials (55-95 wt.%). Non-limiting examples of conductive carbon includes activated carbon, carbon black, graphene, graphite, carbon nanotubes, MXenes, carbide-derived carbons, biomass-based porous carbon or their combinations. The adhesive may also include a solvent, which in some embodiments may be diluted in an aqueous solution, or comprise an aqueous solution, and / or a non-aqueous solvent. The solvent may comprise one or a combination of non-limiting examples such asethanol, methanol, isopropyl alcohol, propanol and n-butanol. The adhesive may also include one or more additives, such as a stabilizer, thickening or emulsifying agent. The thickening agent may comprise any one or a mixture of cellulose-based water- soluble, or solvent polymers. Non-limiting examples include carboxymethyl cellulose (CMC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), and sodium carboxymethyl cellulose (Na-CMC) The adhesive may be applied by a brush, an ultrasonic spray, a splatter, roller, or by a Microgravure™ technique, or by any other suitable technique. A doctor blade may be used to help spread the adhesive evenly on the foil or control the amount of the adhesive on the roller. The thickness of adhesive after drying is about 0.01-10pm, for example. In certain embodiments, priming or applying a coating provides a better adhesion of the fibrillated wet electrode material and increases the foil’s roughness.

[0160] In certain embodiments, the method includes applying a priming glue, wherein the priming glue composition is also prepared by a process of continuous stirring / blending which may or may not include the sonication of the conductive carbon materials in order to obtain a uniform suspension.

[0161] In certain embodiments, the glue composition is made with the addition of a stabilizer, wherein the stabilizer may be used to reduce or prevent phase separation of the glue in order to provide a homogenous material with consistent properties for adhesion and conductivity. A water-based glue may be used in some exemplary embodiments. In certain non-limiting examples to make the glue, a first binder may be dissolved in an excess amount of water. In additional embodiments, conductive carbon materials are then added, followed optionally by a second or plurality of binders after which the combined mixture is stirred. In another embodiment, a glue with a stabilizer may be used. For certain embodiments, the glue may be made with a first binder that may be dissolved in an excess amount of water, then a thickening additive or stabilizer may be added, which may be in a water / alcohol solvent, which may then be mixed with the first binder solution, after this a conductive carbon material or materials may be added, followed by a second binder, and finally followed by stirring the combined mixture.

[0162] In step 306, the foil with the applied adhesive is then optionally dried. This may be achieved, for example, by curing the foil with the adhesive coating in an oven. Drying may not be necessary depending on the preceding steps when applying theelectrode. In some embodiments, the foil may be coated on one side with the adhesive, dried, and then coated on the other side with further adhesive, and then dried again.

[0163] In step 308, after the adhesive has been dried, the fibrillated wet electrode mixture is then applied to one or both sides of the primed foil. In certain embodiments, the foil may be coated on one side with the fibrillated wet electrode mixture that incorporates one or more additional adhesives, then dried, then pressed, followed by, in certain embodiments, a repeat of these steps for the second side of the foil.

[0164] In step 309 a doctor blade may be used to help spread the fibrillated wet electrode evenly on the foil.

[0165] In step 310, the foil with the applied fibrillated wet electrode is dried.

[0166] In step 312, the foil with the dried fibrillated wet electrode is pressed / calendered. It is not necessary to heat-press the coating obtained by incorporating fibrillated material into traditional wet coating methods, however, calendering and or heated pressing is an option that may be included particularly when exclusively using fibrillatable binders, and is preferred. The resulting foil, with one or more adhered electrodes, is referred to as a laminated electrode or multilayer electrode assembly. In certain embodiments, the composition of the glue may vary for the anode and cathode.

[0167] In certain embodiments, the composition of the electrode may vary for the anode and cathode.

[0168] In certain embodiments, the composition of the current collector foil may vary for the anode and cathode.

[0169] In some embodiments, the foil may first be coated on one side with the fibrillated wet electrode mixture, dried, and then coated on the other side with the fibrillated wet electrode mixture, and then dried again. In these embodiments, steps 302-312 are repeated for the second side. In certain embodiments steps 302 to 306 are done for both sides of the foil before proceeding with further steps.

[0170] Optional step 314 involves optionally slitting or trimming the laminated electrode roll into two or more rolls using a slitting machine. If the laminated film has two or more sections, it must be split into two or more. For a supercapacitor with symmetric electrodes, for example, one section is used as the positive electrode and one section as the negative electrode. For an asymmetric device (such as a battery orhybrid supercapacitor / battery), two or more rolls of one type (such as positive or negative electrode) may be produced from slitting.

[0171] In step 316, two laminated electrodes, one to become positive and the other negative, are wound with intervening separator layers into a roll, which is referred to as a jelly roll. The positive and negative electrodes are aligned with each other as they are wound. In certain embodiments two laminated electrodes, one to become positive and the other negative, are aligned with each other and layered with intervening separator layers into a multilayer assembly, which is referred to as a pouch cell or prismatic cell. The separator layers may be, for example, 10-50pm cellulose layers as one non-limiting example, though those skilled in the art will appreciate other materials may be used as a separator.

[0172] In step 318, the jelly roll or multilayer assembly is heated in a vacuum oven to ensure that it is dried. The temperature may be 50-250°C, for example, and the duration of heating from 12 hours to a week or a few weeks, for example. Other drying techniques may be used to remove the residual moisture in the jelly rolls.

[0173] In step 320, in certain embodiments the edges of the foil in the jelly roll are bent over so that they are flat, i.e. perpendicular to the axis of the jelly roll. The separator material prevents shorting between the electrodes.

[0174] In step 321 , in certain embodiments, the bent over edges of each end of the foil in the jelly roll are welded together. The bent over edges are welded to additional upper and lower current collectors. This step is optional as it is also possible to design the can without additional collectors.

[0175] In step 322, in certain embodiments, a terminal is welded or otherwise connected to one of the flattened ends of the jelly roll. This terminal is to become the upper terminal of the electrical energy storage device.

[0176] In step 323, in certain embodiments, an insulator is applied to the jelly roll, around the upper terminal and the exposed edges (negative) of the jelly roll, to prevent short circuiting. The upper terminal is left exposed for eventual electrical connection.

[0177] In step 324, in certain embodiments, the jelly roll is inserted into a cell casing or can, with one or more gaskets around the negative cap on the upper terminal. The cell casing or can has a closed bottom and becomes one of the terminals of the cell. The lower current collector sits on the bottom of the can and is welded to it in certain embodiments.

[0178] In step 326, in certain embodiments the cell casing or can is folded over the upper gasket and the insulation around the upper terminal. The cell casing or can is electrically insulated from the upper terminal.

[0179] In step 328, in certain embodiments, the folded upper part of the cell casing or can is sealed onto the upper gasket. This may be done, for example, by press sealing.

[0180] In step 330, in certain embodiments, the resulting cell is heated in a vacuum oven to ensure that it is dry. Moisture and residual solvents may escape from inside the cell through an injection port in the cell casing or can. The temperature may be 20- 250°C, for example, and the duration of heating from 12 hours to a week or a few weeks, for example. Other drying techniques may be used.

[0181] In step 332, in certain embodiments, the inside of the dried cell is purged via the injection port with nitrogen or other inert gas.

[0182] In step 334, in certain embodiments, the purged can is injected with electrolyte via the injection port. The electrolyte is allowed to saturate the jelly roll over a period of time. In certain embodiments, further electrolyte is added if required and allowed to soak into the jelly roll. In certain embodiments a vacuum may be applied to the cell to ensure electrolyte is pulled into the cell and saturates the cell components. In certain embodiments pressure may force the electrolyte to be injected into the cell and saturate the cell components. In certain embodiments multiple cycles of either vacuum or pressure or combination thereof are used to ensure the electrolyte enters the cell and saturates the cell components.

[0183] In step 336, in certain embodiments the cell casing or can is temporarily sealed with a rubber port cover. In certain embodiments the cell casing is permanently sealed.

[0184] In step 338, in certain embodiments, the cell is aged, by repeatedly charging and discharging the cell, which may include one or more charging and discharging current rates. In certain embodiments aging may be repeated for 1 day to up to a few weeks until the difference in state of charge between two consecutive chargedischarge cycles is less than 0.1%. In certain embodiments the aging or warming-up process might be performed by other methods, e.g., by holding the voltage for a certain time or repeatedly charging and discharging the cell.

[0185] In step 340, in certain embodiments, the temporary seal is opened to allow any built-up gas inside the cell to escape. In certain embodiments where the cell was permanently sealed this step is omitted.

[0186] In step 342, in certain embodiments, a plug gasket is permanently inserted in the cell’s injection port for the electrolyte in order to seal it and to ensure electrolyte retention. The cell’s injection port for the electrolyte is welded over to hermetically seal the cell in certain embodiments. The resulting cell is an electrical energy storage device, such as a supercapacitor, for a non-limiting example.

[0187] Steps 320-342, in certain embodiments, may be replaced by other steps that are for manufacturing other shapes of energy storage device, and could be replaced, for example, by a single generic assembly step.

[0188] In other embodiments, the application of the fibrillated wet electrode material to the current collector may be carried out electrostatically.

[0189] FIG. 9 is a schematic cross-section of a portion of a laminated electrode with the fibrillated wet electrode material for certain embodiments. In certain embodiments, the current collector 360 in one non-limiting example is aluminum foil, though other foils such as copper may be used, coated on both sides with the fibrillated wet electrode mixture 362, 364. The fibrillated binder material is shown schematically in both electrode layers. The fibrils 366 are generally distributed homogenously throughout the electrode layers.B12. Electrostatic Application

[0190] Referring to FIG. 10, a process is shown for adhering a fibrillated wet electrode film and a fibrillated wet electrolyte film to a foil, for subsequent use in a charge storage device.

[0191] In step 418, a fibrillated wet electrode mixture is provided. In step 420, the mixture is nebulized. In step 422, the nebulized mixture is electrostatically charged. In step 424, the fibrillated wet electrode mixture is applied to a foil, then dried and calendered as described above.

[0192] In step 426, a fibrillated wet electrolyte mixture is provided. In step 428, this mixture is nebulized. In step 430, this nebulized mixture is electrostatically charged. In step 432, making use of the forces due to the electrostatic charge on the nebulized mixture, the wet fibrillated electrolyte mixture is applied to the dried electrode, which isalready adhered to the foil. Adhesive may still used to adhere the fibrillated wet electrolyte film to the dried electrode film on the foil; the electrostatic charge assists in the initial contact with the adhesive.

[0193] Referring to FIG. 11 , a process is shown for adhering a fibrillated wet electrode film to an electrolyte-electrode-foil assembly created as a result of step 432 of FIG. 10, for subsequent use in a charge storage device, for example a solid-state battery.

[0194] In step 440, another fibrillated wet electrode mixture is provided. If the electrodes are different, then this is an anode mixture if the existing assembly has a cathode, and vice versa. In step 442, the mixture is nebulized. In step 444, the nebulized mixture is electrostatically charged. In step 446, the fibrillated wet electrode mixture is applied to another foil to result in another electrode assembly. In step 448, this other electrode assembly is layered upside-down on the existing electrolyte- electrode-foil assembly to form a sandwich structure, with the current collector foils on the outside, the electrodes on the inside of the foils and the electrolyte later in the middle. In step 450, the sandwich structure is passed through hot rollers to dry and calender it as described above. In certain embodiments the foils may have electrode and electrolyte layer on both sides to allow for multilayer assemblies.

[0195] Relating to the preparation of the mixture of the powdered active material and the fibrillated binder, the particles in this mixture may be charged. Ionizing devices may be used at various points in the apparatus to charge the particles, and may be used at one or more points. The ionizing device may be, for example, a corona discharge generator.

[0196] An ionizer may be used to charge the active material, which may be size- sorted. An ionizer may be used to charge the binder, which may also be size-sorted. The mixture of active material and the binder may be charged by an ionizer. As the mixture is being fed into the fibrillator, the stream of the mixture passing into it may be charged by an ionizer. During partial to full fibrillation, an ionizer may ionize the mixture as it is undergoing fibrillation. The fibrillated mixture may also be charged with an ionizer.

[0197] After fibrillation, the mixture may be ionized with an ionizer. The resulting, charged, partially to fully fibrillated mixture, irrespectively of how it has been charged, is then mixed with a liquid to form a slurry of fibrillated wet electrode mixture.C. Images

[0198] FIGS. 12 and 13 show SEM images with different magnifications for a partially fibrillated mixture that was obtained by processing the activated carbon and PTFE in an air mill. In these image we observe PTFE that has been broken down into smaller pieces and deformed, which in certain instances is referred to as pre-fibrillated or partially fibrillated. The pre-fibrillated or partially fibrillated PTFE can then be further elongated and form a further fibrous structure in subsequent steps of the process.

[0199] FIG. 14 is an SEM image of a fibrillated wet electrode coated on primed Al foil after being hot-pressed or calendered (laminated electrode). The electrode includes 90 wt% activated carbon, 9 wt% PTFE, and 1 wt% carbon black. The SEM image shows the fibrillated binders bridge and link the active material particles without fully covering them. The magnified area of the SEM image shows PTFE nanofibers.

[0200] FIG. 15 is an SEM image of a water-based ink-type electrode coated on primed Al foil. The electrode includes 90 wt% activated carbon, 9 wt% ink-type binder, and 1 wt% carbon black. The SEM image and the magnified area of the SEM image show that the binder heavily covers the surfaces of the active material particles.

[0201] FIG. 16 is an SEM image of a fibrillated wet electrode coated on primed Al foil before being pressed or calendered. The electrode includes 90 wt% activated carbon, 9 wt% PTFE, and 1 wt% carbon black.

[0202] FIG. 17 is an SEM image of the same fibrillated wet electrode as in FIG. 16, after being hot-pressed or calendered on primed Al foil (laminated electrode). This SEM image shows the homogenous and dense surface of the calendered laminated electrode without any crack or delamination.

[0203] FIG. 18 is an optical image of a fibrillated wet electrode coated on primed Al foil before being pressed or calendered. The electrode includes 90 wt% activated carbon, 9 wt% PTFE, and 1 wt% carbon black.

[0204] FIG. 19 is an optical image of the same fibrillated wet electrode as in FIG. 18 after being hot-pressed or calendered (laminated electrode).

[0205] FIGS. 20-23 are optical and SEM images of a water-based slurry-type electrode coated on primed Al foil. The coating process is similar to fibrillated wet electrode except that the binder is a dispersion of PTFE nanoparticles and without the fibrillation step. The electrodes include 90 wt% activated carbon, 9 wt% PTFEnanoparticles, and 1 wt% carbon black. FIG. 20 is an optical image that shows cracks and delamination of a typical slurry-type electrode with PTFE nanoparticles. This same type of cracking is observed with other ink-type assembly methods as the electrodes become thicker.

[0206] FIG. 21 is an optical image of a slurry-type electrode with PTFE nanoparticles, which has a thin coating of electrode. It is coated from the same batch as the electrode in FIG. 20, but with a thinner coating. FIG. 22 is an optical image of the slurry-type electrode with PTFE nanoparticles after being hot-pressed or calendered (laminated electrode). The image shows the weak binding of electrode materials to the foil even after calendering, as indicated by a gentle finger mark. This indicates the inability of PTFE nanoparticles to bind and hold active materials together, unlike the disclosed fibrillated wet electrode method, which highlights the importance of fibrillating or partially fibrillating the binder. FIG. 23 is an SEM image of the laminated electrode with PTFE nanoparticles of FIG. 22. The magnified area of the image shows micro cracks on the surface of the calendered thin electrode.D. Variations

[0207] While much of the description has focused on the making of a fibrillated wet electrode film, the steps described are also applicable to making fibrillated wet electrolyte films. In certain embodiments a variety of assembly methods and final form factors may be used for energy storage devices as a result of the described invention and benefits thereof, which may include a variety of layered, stacked, wound or offset energy storage assemblies.

[0208] Those skilled in the art will appreciate that the beneficial aspects of the invention may be a result of utilizing one or more of the described steps, wherein one or plurality of steps may be omitted from the production of an energy storage device.

[0209] An energy storage device as described herein may include one or more of the following non-limiting examples: primary battery, secondary battery, capacitors, supercapacitor, capacitor-battery hybrid, hybrid capacitor, lithium-ion capacitor, asymmetric supercapacitor, psuedocapacitor etc. Some non-limiting examples of batteries may include primary batteries (non-rechargeable). Primary batteries include compositions such as alkaline (zinc-manganese dioxide), zinc-carbon, lithium (lithiumiron disulfide), silver-oxide, zinc-air, mercury oxide, lithium-thionyl chloride, lithium-mnganese dioxide, magnesium, zinc-silver oxide, and zinc-mercury oxide. Some nonlimiting examples of batteries may include secondary batteries (rechargeable). Secondary batteries encompass compositions like lithium-ion, nickel-cadmium (NiCd), nickel-metal hydride (NiMH), lead-acid, lithium-polymer, sodium-sulfur, flow batteries (vanadium redox, zinc-bromine), solid-state batteries, nickel-zinc, lithium-titanate, rechargeable alkaline, nickel-iron, sodium-nickel chloride, and zinc-air rechargeable. Some non-limiting examples of batteries may include lithium-ion batteries. Lithium-ion batteries include various compositions such as lithium cobalt oxide (LiCoO?), lithium manganese oxide (LiMn2O4), lithium iron phosphate (LiFePO4), lithium nickel manganese cobalt oxide (NMC), lithium nickel cobalt aluminum oxide (NCA), lithium titanate (Li4TisOi2), lithium manganese nickel oxide (LiNiMnO2), lithium nickel oxide (LiNiC ), lithium manganese cobalt oxide (LiMnCoC ), lithium sulfur (Li-S), lithium air (Li-Air), lithium polymer (Li-Poly), lithium vanadium oxide (LiV20s), lithium nickel manganese cobalt oxide with high nickel content (LiNi0.8Co0.15AI0.05O2), and lithium iron manganese phosphate (LiFeMnPO4) as a few non limiting examples.

[0210] In certain embodiments, the form or design of the cell may be different, e.g. it may be a wound cell, pouch cell, a prismatic cell, a multilayer assembly, etc.

[0211] Binders other than PTFE may be used instead of the PTFE or in combination, for example, PVDF (polyvinylidene fluoride) or ultra-high molecular weight polyethylene may be used. The described system and method include an electrode film prepared by a fi bril lated wet method, wherein the electrode powder mixture may include at least one type of binder such as polytetrafluoroethylene (PTFE), polyvinylpyrrolidone (PVP), PVDF, polyethylene oxide (PEO), or carboxymethylcellulose (CMC) or polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP)

[0212] Mixers other than vacuum mixers may be used, provided that the activated carbon, PTFE, optional conductive additive, and after fibrillation liquid such as water are thoroughly mixed. This is provided that, as well, during the liquid mixing the fibrillated electrode mixture is mixed into a uniform and homogeneous mixture. Mixing may involve multiple mixers.

[0213] The current collector foil may be a metal other than aluminum, such as copper. Non-limiting examples of the current collector material include aluminum, baked carbon, copper, nickel, stainless steel which is optionally surface-treated withcarbon and / or a binder, steel or iron with optional surface-treatment, silver, stainless steel, titanium or the like. The current collector material and / or composition is not particularly limited, though it is preferred to have a high conductivity, and whereby it does not cause any chemical change or side reactions in the energy storage device.

[0214] The current collector may additionally be processed to have fine surface irregularities on the surface (enhance its roughness) of the current collector which may enhance the binding force with the fi bril lated wet electrode mixture, which may additionally reduce the surface tension between the current collector and electrode film. The current collector may be in various shapes, including a foil, a film, a sheet, a net, a weave, a mesh, a porous body, a foamed body, a non-woven web, or the like.

[0215] In certain embodiments, a conductive material may be used to increase conductivity of the electrode material and / or priming layer, which is not limited to any particular material as long as it has conductivity while not causing any chemical change in the corresponding energy storage device. Non-limiting examples of the conductive material may include: acetylene black, carbon black, channel black, furnace black, lamp black or ketjen black, thermal black; graphene; conductive fibers, examples of which include carbon fibers and metal fibers; metal powder, such as aluminum and nickel; fluorocarbon; a conductive whisker, examples of which include zinc oxide and potassium titanate; one or more conductive metal oxides, an example of which includes titanium dioxide; one or more conductive polymers, examples of which include polyphenylene derivatives. In exemplified embodiments, the conductive material may include one or more of the following: activated carbon, carbon black, carbon nanotubes, graphite.

[0216] Depending on the conductivity of the electrode active material, a conductive material may be required and / or is beneficial to be added to the electrode or electrolyte powder mixture. The conductive material may make up a minority of the powder mixture in an amount 0-20% (e.g., 5%) by weight, as one non-limiting example. Some non-limiting examples of conductive materials may include one or more, for a nonlimiting example a combination of two, of: a conductive carbon such as carbon black and / or acetylene black, graphene and / or Curved Graphene™ as described by Skeleton Technologies of Estonia, ketjen black, or Super P® (e.g. carbon black sold by Imerys Graphite & Carbon of Switzerland), activated carbon, carbon nano-tubes(CNT), graphite particles, or partially graphitic carbons such as a partially graphitic active carbon composition, a conducting polymer, or combinations thereof.

[0217] In an exemplary method of producing an electrode for an energy storage device and the described fibri Hated wet electrode by means of partially to fully fibrillating the electrode mixture and then incorporating a liquid by means of the disclosed system and method, the system and method to produce an electrode includes the following steps: a step of mixing electrode materials together; an optional step of drying mixed electrode materials; a step of conveying dry mixed electrode materials to a fibrillating machine; a step of partially to fully fibrillating electrode materials; a step of conveying fibrillated mixed electrode materials to a mixing machine, and or pressing machine; an optional step of mild heat pressing the partially fibrillated material to further fibri Hate it; a step of mixing the fibrillated electrode material with a liquid such as water; an optional step of mixing in functional additives, an optional step of mixing and or heating the mixture; a step of conveying fibrillated mixed wet electrode materials to an injection machine; a step of injecting the fibrillated wet electrode mixture onto a current collector; a step of providing a uniform layer of the desired thickness of the fibrillated wet electrode mixture on the surface of a current collector; a step of drying the fibrillated wet electrode mixture applied to the current collector; a step of feeding the dried electrode into a heated roller press to adhere the dried electrode to the current collector and calender and further fibrillate the dried electrode, which may include an optional step of heating the fibrillated particles; a step of compressing the fibrillated particles which are optionally heated; a step of controlling heated roller rotation speed, controlling electrode assembly production speed, controlling the roller press gap distance, controlling said rollers’ pressure, controlling desired electrode thickness; optionally repeating one or more of the preceding steps on the opposing side of the current collector.

[0218] In an exemplary method of producing an electrode and energy storage device and the described fibrillated wet electrode by means of partially to fully fibrillating the electrode mixture and then incorporating a liquid by means of the disclosed system and method, the system and method to produce an electrode includes the following steps: a step of optionally pre-treating a current collector foil with heat and / or chemical(s); a step of optionally priming pretreated current collector foil with an adhesive such as a conductive glue or conductive binder; a step of adhering afibri Hated wet electrode to the first side of a primed current collector; a step of drying the first side of an electrode assembly; a step of pressing the electrode assembly by means of a heated roller press machine; a step of optionally priming a second side of an optionally pre-treated current collector; a step of adhering a second fibrillated wet electrode film to a second side of an optionally primed current collector; a step of drying the second side of an electrode assembly; a step of pressing the electrode assembly by means of a heated roller press machine; a step of slitting an electrode; a step of vacuum heating and drying the laminated electrodes; a step of winding anode, cathode, and separators to form an energy storage device jelly roll and furthermore for the assembly of an energy storage device; a step of heating and drying jelly rolls in a vacuum oven; a step of bending jelly roll foil edges flat; a step of welding an upper current collector on the jellyroll; a step of welding a lower current collector on the jellyroll; a step of welding an upper terminal on the upper current collector of a jellyroll; a step of providing an insulator around exposed edges of the jellyroll and upper terminal to prevent short circuiting; a step of inserting the jellyroll in a cell case or can with one or more gaskets; a step of folding the cell casing over the gasket and upper terminal; a step of press sealing the folded upper casing into the gasket; a step of heating and drying the jelly roll cells in a vacuum oven and purging with nitrogen or inert gas; a step of injecting electrolyte; a step of letting electrolyte saturate the jellyroll electrodes; a step of injecting electrolyte a second or plurality of times; a step of temporarily sealing cell case; a step of charging and discharging the cell, generally called cell aging; a step of removing the temporary cell seal to allow excess gas to escape cell; a step of inserting a permanent plug in the cell to seal the cell; a step of welding the injection port to hermetically seal the cell.

[0219] Devices and electrode types: In an exemplary embodiment, the electrochemical energy storage device is a supercapacitor. In certain embodiments, the energy storage device is a symmetric supercapacitor in which both electrodes are the same. In some embodiments, the energy storage device is a hybrid or asymmetric supercapacitor where both electrodes and / or electrode substrates are different. In some embodiments, the active material of an electrode stores electrical energy mainly using the electrical double-layer (EDL) mechanism (a so-called EDL-type electrode). In some embodiments, the EDL-type electrode material is electrically conductive and porous with micropores, mesopores and macropores. In the preferred embodiment, theactive material of an electrode includes an activated carbon. In some embodiments, the EDL-type electrode material is selected from conductive porous carbons such as activated carbons, mesoporous carbons, hierarchical porous carbons, graphene-based materials, activated graphene, exfoliated graphite, activated exfoliated graphite, carbon nanotube-based materials, carbide-derived carbons, and / or combinations thereof. In some embodiments, the active materials of electrodes include conductive porous materials with functional groups such as oxygen-containing and nitrogen-containing groups. In some embodiments, the active materials of electrodes include conductive porous materials which are doped with heteroatoms such as nitrogen, oxygen, sulfur, phosphorus, chlorine, bromine, and iodine. In some embodiments, the active material of electrodes is a nanostructure with a certain shape, size, and porosity.

[0220] In some embodiments, the active material of the energy storage device electrode may be a pseudocapacitive material which takes advantage of reversible surface or near-surface Faradaic reactions to store charge. In some embodiments, the pseudocapacitive materials are selected from conducting polymers (such as polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene (PEDOT)-based polymers), transition metal oxides and hydroxides (such as RuO?, V2O5, NiOx, CoOx, FeOx, MnO?, Ni(OH)2, Co(OH)2), and nitrides (such as vanadium nitride), sulfides (such as vanadium disulfide) and / or combinations thereof. In some embodiments, the active material is a so-called Mxene, a class of two-dimensional inorganic compounds that have atomically thin layers of transition metal carbides, nitrides or carbonitrides.

[0221] In some embodiments, the electrode materials of an asymmetric supercapacitor are selected from EDL-type materials, pseudocapacitive material, or their composites. In some embodiments of the energy storage device, one electrode is EDL-type and the other one is pseudocapacitive.

[0222] In some embodiments, the energy storage device is a hybrid supercapacitor wherein one electrode is a capacitor type, and the other one is a battery type. In some embodiments, the cathode material in the hybrid supercapacitor is EDL-type, pseudocapacitive, or their composite. In some embodiments, the battery-type anode is selected from an insertion type (such as lithium titanate (LTO), V2O5, Nb20s), a conversion type (such as FesO4), alloy type (such as silicon, tin), metallic (zinc), a carbonous material, and the like. In some embodiments, the battery-type anode is a composite of two or more materials. In some embodiments, the energy storage deviceis lithium-ion capacitor, wherein the anode active material allows for reversible intercalation of lithium ions such as lithium titanate (LTO, Li^isO-i?). In some embodiments, the energy storage device is a zinc-ion capacitor, wherein the anode active material allows for reversible plating and stripping of zinc ions such as metallic zinc or a zinc-based composite. In some embodiments, the energy storage device is sodium-ion capacitor.

[0223] In some embodiments, the energy storage device is a rechargeable (or secondary) battery. In some embodiments, the energy storage device is lithium-ion battery. In some embodiments, the anode active material in the energy storage device is selected from a carbonaceous material (e.g. graphitic carbon, graphite, graphenebased materials, hard carbon, soft carbon, carbon nanotubes, porous carbon), a silicon-based material (e.g. silicon and silicon dioxide), lithium titanate (LTO, Li4TisOi2), tin, tin oxide (SnOx), molybdenum oxide (MoO?), molybdenum disulfide (M0S2), nickel oxide (NiOx), copper oxide (CuOx), and / or combinations thereof. In some embodiments, the cathode active material in an energy storage device is selected from a carbonaceous material, a lithium nickel manganese cobalt oxide (NMC, e.g. Li(NiMnCo)O2), a lithium manganese oxide (LMO, e.g. LiMn2O4), a lithium cobalt oxide (LCO, e.g., LiCoO2), a lithium nickel cobalt aluminum oxide (NCA, e.g.LiNi0.8Co0.15AI0.05O2), LiMn1.5Nio.5O4 (LMNO), an olivine (such as LiFePO4), chalcogenides (LiTiS2), favorite (LiFeSO4F), manganese oxide (MnOx), sulfur, lithium sulfide (Li2S), and / or combinations thereof. In some embodiments, the energy storage device is sodium-ion battery. In some embodiments, the battery is zinc-ion battery.

[0224] Electrolyte: In some embodiments, the electrolyte is selected from; an aqueous electrolyte, super-concentrated aqueous electrolyte, hybrid electrolyte, or organic electrolytes, which may also include solid state electrolytes. In some embodiments, an organic electrolyte comprises at least one salt in at least one organic solvent or other non-aqueous solvents. In some embodiments, the super-concentrated aqueous electrolyte comprises at least one metal salt in water with a molal concentration between 1m and 100m. In some embodiments, the hybrid electrolyte further comprises at least one salt in a mixture of water and at least one non-aqueous solvent, wherein the molal concentration is between 0.1 m and 20m, wherein the volume percent of water in the solvent mixture is between 1% to 99%, wherein thenon-aqueous solvent(s) is an organic solvent or other solvents, and wherein the salt can be selected from any kind of organic salt or inorganic salt.

[0225] Foil / substrate: In some embodiments, the electrode substrates or foils are selected from metals such as aluminum (Al), copper (Cu), titanium (Ti), nickel (Ni), stainless steel (ss), a metal-based alloy, and carbonous materials such as graphite foil. In some embodiments, the current collector foil for the anode and cathode are different, e.g. in a lithium-ion battery, one may be copper and the other aluminum.

[0226] Separator: In some embodiments, the separator is electrically insulative and has pores. In the preferred embodiment, the separator is a cellulose separator. In some embodiments, the separator is selected from glass fibres, cellulose derivatives, polymer membranes such as polypropylene, polyethylene, polytetrafluoroethylene, PVDF, and polyvinyl chloride, or their combinations. In at least one embodiment, the thickness of the separator is in a range between 5pm and 100pm. In some embodiments, the separator comprises multiple layers. In some embodiments, the separator may be coated with other materials.

[0227] Binder for fi bri Hated mixture: In the preferred embodiment, the binder(s) are selected from a material than can be fibrillated. In some embodiments, the binder is polytetrafluoroethylene (PTFE). In some embodiments, the binder is selected from a group consisting of PTFE, PVDF, polyvinyl alcohol (PVA), polyvinyl acetate, polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), cellulose, carboxymethyl cellulose, PEO, polypropylene (PP), and their combinations.

[0228] Binder: Water-based or non-water based conductive glue may be prepared using one or more binders and an additional conductive additive and optionally active materials. In some embodiments therein an aqueous (water based), or non-aqueous, or organic liquid (organic solvent) formed with one or more additional binder materials is used to form a conductive glue used to bond (attach) the electrode, such as a slurry or film, to the substrate foil, which in some embodiments composes the priming layer and in additional embodiments is incorporated directly into the fibrillated wet electrode mixture. In the preferred embodiment, the liquid is water. In some embodiments, the conductive glue includes of one or more binders, one or more conductive additives, one or more solvents or liquids, optionally wetting agent, optionally stabilizer, and optionally active materials. In some embodiments, the binder is selected from a group including PTFE, PVDF, polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), cellulose,carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), casein, sodium alginate, gum arabic, gellan gum, xanthan gum, guar gum, polyethylene oxide (PEO), polyethylene glycol (PEG), gelatin, chitosan, polyvinyl alcohol (PVA), polyvinyl acetate, or their combinations.

[0229] In certain embodiments, the fibril lated wet electrode may form the positive electrode (cathode), which may include positive electrode active material, wherein nonlimiting examples may include: lithium transition metal oxides, examples may include lithium nickel-manganese-cobalt oxides; lithium nickel-manganese-cobalt oxide which may be partially substituted with other transition metals; lithium iron phosphorus oxides; or similar materials.

[0230] In certain embodiments, the fibril lated wet electrode may be made of active material which may include any one or more non-limiting examples selected from lithium transition metal oxides, lithium metal iron phosphorus oxides and metal oxides, though this is not limited those described herein. In certain embodiments, the electrode mixture may form the positive electrode and be made of active electrode materials which may include one or more of the following non-limiting examples: a layered compound, for instance lithium nickel oxide (LiNiO?) and / or lithium cobalt oxide (LiCoO?), wherein the active electrode materials may include one or more transition metals; non-limiting examples may include lithium manganese oxides, for instance those represented by the chemical formula of Lii+xMn2-xO4 (wherein x is 0-0.33), LiMnOs, LiMn2C>3 and LiMnC ; lithium copper oxide (I 2CUO2). Additionally the active electrode materials may include vanadium oxides such as non-limiting examples of I V3O4, LiVsOs, V2O5 and / or CU2V2O7; Ni-site type lithium nickel oxides represented by the chemical formula of LiNii-xMxO2 (wherein M is Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x is 0.01-0.3), for instance Li(Ni, Co, Mn, AI)O2, and wherein in certain embodiments the fraction of Ni is 50% or more of the metals except Li, lithium manganese composite oxides represented by the chemical formula of LiMn2-xMxO (wherein M is Co, Ni, Fe, Cr, Zn or Ta, and x is 0.01-0.1 ) and / or Li2MnsMO8 (wherein M is Fe, Co, Ni, Cu or Zn); LiMn2O4 in which Li is partially substituted with an alkaline earth metal ion; lithium metal phosphorous oxides LiMPO4 (wherein M is Fe, Co, Ni or Mn); disulfide compounds; and / or Fe2(MoO4)s; or similar materials though not limited by description to those stated herein.

[0231] In certain embodiments, the electrode mixture may form the electrode which may be a negative electrode, and the active material may include a negative electrode active material. Non-limiting examples of the negative electrode active material may include: carbon material or carbonous material or carbon such as activated carbon, graphite-based carbon, non-graphitizable carbon and / or metal composite oxides examples may include LixFe2O3(0 :S x :S 1 ), LixWO? (0 :S x :S 1) and / or SnxMe-i-xMe'yOz (Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, which include elements of Group 1 , 2 or 3 in the Periodic Table, halogen; 0 < x :S 1 ; 1 :Sy :S 3; 1 :S z :S 8); lithium alloy; lithium metal; silicon-based alloy; tin-based alloy; silicon oxides examples include SiO, SiO / C and / or SiO?. Additionally, in certain embodiments, the negative electrode mixture may include metal oxides, such as Bi?O3, Bi?O4 and Bi20s; GeO, GeO?, PbO, PbO?, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb20s, SnO, SnO?. Additionally, in certain embodiments, the negative electrode mixture may include conductive polymers which may include Li-Co-Ni type materials; polyacetylene as a few non-limiting examples.

[0232] Electrolyte Materials: In certain embodiments, the fi bril lated wet electrolyte may be 80-100% by weight a ceramic material such as a non-limiting examples an oxide such as a garnet-structure oxide, additional examples may include; lithium lanthanum zirconium niobium oxide (LLZNbO) (e.g. Li6.5La3Zr1.5Nbo.5O12), lithium lanthanum zirconium oxide (LLZO) with various dopants (e.g. Li6.sLa3Zr20i2 or Li?La3Zr20i2), lithium lanthanum zirconium tantalum oxide (LLZTO) (e.g.Li6.4La3Z1.4Tao.6O12), lithium lanthanum zirconium tungsten oxide (LLZWO) (e.g. Li6.3La3Zri.65Wo.350i2), which may additionally comprise a perovskite-structure oxide, for example, lithium aluminum titanium phosphate (LATP) (e.g. Lii.4Alo.4Tii.6(P04)3), and / or lithium lanthanum titanate (LLTO) (e.g. Lio.sLao.sTiOs, Lio ^Lao.seTiOs, or Lio.29Lao.57 TiO3), additionally non-limiting examples of additional materials include a lithium superionic conductor Li2+2XZni-xGeO4 (LISICON), for example lithium aluminum germanium phosphate (LAG or sodium superionic conductor i.e. NASICON-type LAGP) (e.g. Lii.5Alo.5Gei.5(P04)3or Lii.sAlo.sGei.sPsOi?), lithium aluminum titanium phosphate (LATP) (e.g. Lii.3Alo.3Tii.7(P04)3), additionally a phosphate material or additive for example, lithium germanium phosphate (LGPO) (e.g. LiGe(PO4)3), lithium titanium phosphate (LTPO) (e.g. LiTi(PO4)3), lithium phosphate (LPO) (e.g. gamma- Li3PO4 or Li7P), and / or lithium phosphorus oxynitride (LiPON).

[0233] In certain embodiments, the fibril lated wet electrolyte may include a polymer which may be 80-100% of the powder by weight: non-limiting examples may include; PEO, PEO-LiTFSI, PEO-LiTFSI / LLZO, PEO-LiCIC , PEO-LiCIC LLZO, PEO-PTFE, poly(3,4-ethylenedioxythiophene), polyethylene glycol (PEG), polyphenylene oxide (PPO), polystyrene sulfonate (PEDOT:PSS), a polyether-based polymer, a polyester- based polymer, a nitril-based polymer, a polysiloxane-based polymer, polyurethane, poly-(bis((methoxyethoxy)ethoxy)phosphazene) (MEEP), and / or polyvinyl alcohol (PVA).

[0234] In additional embodiments the fibri Hated wet electrolyte may include a sulfide of 80-100% by weight: non-limiting examples may include; lithium sulfide (LS) (e.g. l_i2S), glassy lithium sulfide boron sulfide (LSBS) (e.g. Li2S-B2Ss), lithium germanium sulfide (LGS) (e.g. Li4GeS4), lithium phosphorus sulfide (LPS) (e.g. I 3PS4 for instance 75I 2S-25P2S5 and / or LizPsSn for instance 70Li2S-30P2Ss), glassy lithium sulfide phosphorus sulfide (LSPS) ( e.g. I 2S-P2S5), glassy lithium sulfide silicon sulfide (LSSiS) (e.g. Li2S-SiS2), lithium silicon phosphorus tin sulfide (LSPTS) (e.g.Lix(SiSn)PyS2), argyridite LiePSsX (X=CI, Br) (e.g. LPSBr for instance LiePSsBr, LPSCI for instance LiePSsCI, LPSCIBr for instance LiePSsClo.sBro.s, or LSiPSCI for instance Li9.54Si1.74P1.44Sn.7CI0.3), or thio-LISICON (e.g. LGPS for instance Li-ioGePS-12).

[0235] In certain embodiments, the powder mixture may contain a lubrication material such as a polymer-containing additive solution or conductive paste which in additional embodiments may be added prior to adding the binder and which in additional embodiments may include a liquid carrier which may be a relatively small amount of liquid to have the powder mixture remain a powder or relatively dry powder.

[0236] In certain embodiments, the additive may be 0.1 %-20% by weight, and may be a polymeric compound, surfactant or viscous liquid; examples include mineral oil or wax. These additives may act as a dispersant for carbon nanotubes or as a binder.Examples may include materials described in U.S. Pat. No. 8,540,902, which provides specific examples of dispersants and polymeric binders such as thermoplastic polyester resin, polyethylene, polypropylene, polyamide, polyurethane, polyvinyl chloride, polyvinylidene fluoride, polyvinylpyrrolidone, polystyrene sulfonate, polyphenylacetylene, polymetaphenylenevinylene, polypyrrole, polypphenylene benzobisoxazole, natural polymers, amphiphilic materials in aqueous solutions, anionic aliphatic surfactant, cyclic lipopeptido bio surfactant, sodium dodecyl sulfate,water-soluble polymers, polyvinyl alcohol sodium dodecyl sulfate, polyoxyethylene surfactant, PVDF, carboxyl methyl cellulose (CMC), hydroxyl ethyl cellulose polyacrylic acid, polyvinyl chloride as non-limiting examples and may include one or more of the described or combinations thereof. Additional examples of polymer additive or binder may include styrene-butadiene rubber (SBR). The liquid additive which may be used as a dispersion material or carrier and may be used to produce the additive solution may include an aqueous or non-aqueous additive, and non-limiting examples may include one or more of the following chemicals such as: acetone, an acetate ester, an alcohol, diethyl carbonate, dimethyl carbonate, ethanol, a glycol, a hydrocarbon, isopropanol, and particularly n-methyl-pyrrolidone.

[0237] In an exemplified embodiment of the present disclosure, there is provided an energy storage device as described as a secondary battery. In an exemplified embodiment of the present disclosure, there is provided an energy storage device as described as a primary battery. In an exemplified embodiment of the present disclosure, there is provided an energy storage device described as a supercapacitor. In certain embodiments, the fi bril lated wet electrode may be used for an electrochemical device which may be a primary or secondary battery, particularly a lithium-ion secondary battery; another example may include a supercapacitor, hybrid or pseudocapacitor.

[0238] Electrode Battery Material: The active material of the electrode in exemplary embodiments may make up the majority of the powder mixture, a non-limiting example being 70-99% (e.g. 90%) by weight. The active electrode material of the cathode may include a lithium metal oxide; some non-limiting examples may include lithium nickel cobalt aluminum oxide (NCA), lithium nickel manganese oxide (LMNO), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NCM), etc. The active electrode material of the anode may include, to name a few non-limiting examples, graphite, silicon dioxide (SiO?), a mixture of the two, etc.

[0239] In certain embodiments, the fibril lated wet electrode mixture may include a positive electrode active material to make up the majority of the powder mixture, a nonlimiting example being 70-99% by weight, including lithium transition metal oxides; examples may include lithium cobalt oxide (LiCoC ), lithium iron phosphate (LiFePC>4), lithium nickel manganese cobalt oxide (LiNixMnyCozO2), lithium manganese oxide (LiMn2C>4), lithium nickel oxide (Li NiC>2), lithium nickel cobalt aluminum oxide(LiNi0.8Co0.15AI0.05O2), lithium-rich layered oxides (Lii+xTMi-xO2, TM: transition metal), vanadium oxides such as LiVaC , LiVsOs and V2O5.

[0240] In certain embodiments, the fibril lated wet electrode mixture may include a negative electrode active material of 70-99% by weight; non-limiting examples may include synthetic graphite, natural graphite, carbon, tin oxide (SnOx), titanium oxide (TiO2), lithium titanium oxide (Li4Ti50i2), silicon-graphite, silicon oxide (SiOx).

[0241] In certain embodiments the fibrillated wet-electrolyte may be 70-99% by weight of ion-conducting inorganic ceramic oxides; non-limiting examples may include garnet-based ceramics such as LiyLasZ^O^, perovskites such as Lao.57Lio.29Ti03, Li- superionic conductors (LISICON) such as Lii+xAlxTi2X(PO4)3, sodium superionic conductors (NASICON) such as Lii.3Alo.3Tii.7(P04)3.

[0242] In certain embodiments, the fibrillated wet electrolyte may include a sulfide- based inorganic material; non-limiting examples may include lithium sulfide (Li2S), lithium sulfide boron sulfide (Li2S-B2Ss), lithium germanium sulfide (Li4GeS4).

[0243] In certain embodiments, the fibrillated wet electrolyte may include an ionconducting polymer such as polyethylene oxide (PEO), PVDF, poly(vinylidene fluoride- co-hexafluoropropylene) (PVDF-HFP), polyethylene glycol (PEG), and other additives including but not limited to a salt such as LiTFSI, LiCIO4, LiPFe, and / or ion-conducting oxides or sulfides such as those mentioned in the above statements.

[0244] The binder or adhesion material may include a material soluble in a solvent, e.g. water, or be formed as an acrylic binder, or the like.

[0245] In some embodiments, the binder may include a non-fibrillated fibrillatable resin and a thermoplastic polymer. The thermoplastic polymer may have a low melting point, at or below 375°C, e.g. below 200°C. In some embodiments, it is a fluoropolymer, e.g. PVDF, polyfluoroethylene-propylene (FEP), polyethylene fluoroethylene propylene (EFEP), polyethylene tetrafluoroethylene (ETFE), PTFE, hexafluoropropylene, vinylidene fluoride, fluoroelastomers (e.g. FKM and FFKM), polyperfluoroalkoxy alkane, polyvinyl fluoride, and alloys and blends thereof. In other embodiments, it may be a non-fluorinated polymer, examples of which include, but are not limited to, polyolefins such as polyethylene and polypropylene, polyamide such as nylon, polystyrene, thermoplastic polyurethane, polyimide, polyacrylate, polycarbonate, polylactic acid, polyether ether ketone, PEG, and alloys and blends thereof.

[0246] The thermoplastic polymer may be used in particulate form, as an emulsion or as a resin. Examples of the resin include non-fluorinated polymers such as polyethylene, polypropylene, polyamide, polystyrene, thermoplastic polyurethane, polyimide, polyacrylate, polycarbonate, polylactic acid, polyether ether ketone, and polyethylene glycol; and fluoropolymers. The resin may include polyethylene or a fluoropolymer. Examples of the fluoropolymer include a tetrafluoroethylene (TFE) / perfluoro(alkyl vinyl ether) copolymer, a TFE / hexafluoropropylene copolymer, ETFE, a TFE / HFPNDF copolymer, a VDF / TFE copolymer, EFEP, polychlorotrifluoroethylene, a chlorotrifluoroethylene (CTFE) / TFE copolymer, an ethylene / CTFE copolymer, PVF, and PVDF.

[0247] In the binder, the number of fibrillatable resin particles having an aspect ratio of 30 or higher is 0.5-20% of the total. A non-fibri Hated fibrillatable resin means that the number of fibrillatable resin particles having an aspect ratio of 20 or higher is 0.5-20% of the total.

[0248] The PTFE, where used as the binder, may be a homopolymer of TFE or may be a modified PTFE containing a polymerized unit based on TFE (TFE unit) and a polymerized unit based on a modifying monomer (modifying monomer unit). The modified PTFE may contain 99.0 wt% or more of the TFE unit and 1 .0 wt% or less of the modifying monomer unit. The modified PTFE may consist only of a TFE unit and a modifying monomer unit. In order to achieve improved binding force, improved electrode strength, and improved electrode flexibility, the PTFE is a modified PTFE.

[0249] In some embodiments, the electrode mixture prepared for use in an energy storage device may undergo an activation step (reference in U.S. Pat. No.11 ,616,218). Some non-limiting examples of materials that may be used in an activation step include solvents added to the electrode mixture. Non-limiting example solvents may include acetates (e.g. methyl acetate, ethyl acetate), hydrocarbons (e.g. hexane, benzene, toluene), alcohols (e.g. butanol, ethanol, isopropyl alcohol, methanol, propanol), acetone, dimethyl carbonate, diethylcarbamazine, glycols, tetrachloroethylene, etc.

[0250] In certain embodiments, the fibril lated wet electrode materials may include 70--98 wt% active material; 0.5-10 wt% conductive material; 0.5-10 wt% binder. In exemplary embodiments the fibril lated wet electrode materials may include 85-98 wt% active material; 0.5-5 wt% conductive material; 0.5-10 wt% binder.

[0251] In certain embodiments, the electrode mixture for use in an energy storage device may be partially composed of a filler. In certain embodiments, the filler may be an ingredient utilized to inhibit the electrode from swelling. In additional embodiments the electrode mixture for use in an energy storage device does not include a filler. In certain embodiments, a filler may not be needed in the electrode as certain fibrillatable material such as PTFE show good ability to limit swelling of the electrode.

[0252] In certain embodiments, wherein the fibrillated electrode mixture, and / or pre- fibri Hated electrode mixture, and / or active electrode material, undergoes a kneading step, the kneading may be carried out by using a kneader machine. In certain embodiments, a few non-limiting examples of devices that may be used for the kneading step include a kneader, a batch kneader, a continuous kneader, a twin screw extruder, a single screw extruder.

[0253] In certain embodiments, utilizing the present disclosure, a method to prepare a fibrillated wet electrode for use in an energy storage device may benefit by eliminating a drying step for removing toxic solvents such as NMP from the powder mixture or fibrillated wet electrode. In certain embodiments, utilizing the present disclosure, a method to prepare a fibrillated wet electrode for use in an energy storage device may benefit by eliminating the solvent recovery for toxic solvents such as NMP from the electrode.

[0254] The film for use in an energy storage device according to the present disclosure may show increased flexibility, tensile strength, and / or durability, therefore, when the film is initially wound and stored, or subsequently unwound, minimal to no breakage or cracking is observed, advantageously.

[0255] In alternative processes for producing energy storage devices that utilize alternative methods, wet methods, and partially wet methods, or dry methods with additives, the disclosed method of pre-sorting the active electrode material, by particle size sorting and removing smaller particles, may be beneficial. In addition, in certain embodiments, this approach may be beneficial to alternative dry electrode processes in which the powder mixture is blended and extruded into films directly, with or without addition of additives, solvents or other liquids.

[0256] The electrode may be produced by various methods; some non-limiting examples include traditional wet “slurry” coating methods, extrusion methods, and dry methods, as a few non-limiting examples and the described system and methodfeatures and benefits may be utilized for such methods. The process disclosed herein may then be used to apply a fibri Hated wet electrode layer to the traditionally manufactured electrode assembly.

[0257] In some embodiments, the fibril lated wet electrode manufacturing method can be utilized to coat (spray) catalyst onto a gas diffusion layer (substrate), resulting in a gas diffusion electrode (GDE). In some embodiments, an energy conversion device in a building transforms energy from one form to another, and may comprise the use of a GDE, wherein non-limiting examples may include fuel cells. In some embodiments, the GDE employed in the fuel cells facilitates the electrochemical reactions between hydrogen (fuel) and oxygen (oxidant) to generate electricity and water. Non-limiting examples of fuel cells include polymer electrolyte membrane (PEM), solid oxide, alkaline, phosphoric acid, and molten carbonate.

[0258] In an exemplary embodiment, the electrochemical energy storage device is a redox flow battery (RFB); a type of rechargeable device that stores energy in liquid electrolyte solutions containing dissolved redox (reduction-oxidation) active species. In other embodiments, the battery's two electrodes can be carbon-based materials that serve as substrates, with the catalyst coated onto them to promote a reversible oxidation-reduction (redox) reaction between two liquid electrolytes carrying distinct active species. In some embodiments, a fibrillated wet electrode design can be employed to ensure catalyst deposition on the electrode surface. All-vanadium, ironchromium, zinc-bromine, hydrogen-bromine, and / organic RFBs are all non-limiting examples of active species used in RFB systems. Embodiments, depending on their configuration, may exhibit all or fewer than all of the advantages described herein. Other advantages not mentioned may be present in one or more of the embodiments.

[0259] Features from any of the embodiments may be combined with features from any of the other embodiments to form another embodiment within the scope of the invention.

[0260] All parameters, dimensions, angles, materials, quantities and configurations described or shown herein are examples only and may be changed depending on the specific embodiment implemented. Temperatures that have been given to the nearest degree include all temperatures within a range of ±0.5°C of the given value. Likewise, numbers and percentages are specified to the nearest significant digit. All ranges given include all subranges within the range. For example, if a range is given as m-q, thenthe ranges m-n, n-p and p-q are included, where n and p are any values that satisfy m<n<p<q. In general, unless otherwise indicated or clear from the context, singular elements may be in the plural and vice versa with no loss of generality.

[0261] It will be clear to one having skill in the art that further variations to the specific details disclosed herein can be made, resulting in other embodiments that are within the scope of the invention disclosed.

[0262] Throughout the description, specific details have been set forth in order to provide a more thorough understanding of embodiments of the invention. However, the invention may be practised without these specific details. In other instances, well known elements have not been shown or described in detail and repetitions of steps and features have been omitted to avoid unnecessarily obscuring the invention.Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense. It will be clear to one having skill in the art that variations to the details disclosed herein can be made, resulting in other embodiments that are within the scope of the invention disclosed. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the claims.

[0263] Terms used herein and throughout this disclosure, should not be construed as limited to general and dictionary meanings, and include the appropriate definition as defined by the inventor, on the principle the inventor is allowed to define terms in order to provide the best explanation of the invention or particular aspect thereof.

[0264] The terminology used herein is for the purpose of describing and depicting particular embodiments of the invention and is not intended to be limiting for any particular aspects or embodiments of the disclosed invention.

[0265] Throughout the description and specification contained herein the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0266] The terms "comprises" and / or "comprising", or "includes" and / or "including" if and when used in this specification, are not intended to preclude the presence of other elements but also specify the possible presence of other elements, unless otherwise stated.

[0267] The entire disclosure of every reference cited herein is incorporated herein in its entirety.

Claims

CLAIMS1. A method for manufacturing a conductive layered assembly for an energy storage device, the method comprising the steps of: mixing dry, powdered active material with a binder to form a mixture; fibri Hating the mixture to obtain a partially to fully fi bril lated mixture; mixing the partially to fully fibrillated mixture with a liquid to form a slurry; applying the slurry to a substrate comprising a conductive foil; and drying the slurry on the substrate to form the conductive layered assembly.

2. The method of claim 1 , further comprising adding and mixing one or more additives into the slurry.

3. The method of claim 2, wherein the one or more additives comprise one or more functional additives.

4. The method of claim 1 , further comprising adding a conductive additive to the mixture before the fibri Hating step and / or during the second mixing step.

5. The method of claim 1 , further comprising calendering the conductive layered assembly between rollers at a temperature between 50°C and 160°C.

6. The method of claim 5, wherein the calendering increases adhesion of the dried slurry to the substrate and compacts the dried slurry.

7. The method of claim 1 , wherein the liquid comprises water.

8. The method of claim 2, wherein the one or more additives are selected from another binder, a stabilizer, a wetting agent, and a surfactant.

9. The process of claim 1 , wherein the mixture comprises by weight:0-5% of functional additives; and0-20% of a conductive additive.

10. The method of claim 1 , wherein: the dry, powdered active material comprises activated carbon; the substrate is a current collector; and the dried slurry on the substrate is an electrode.

11. The method of claim 1 , wherein: the dry, powdered active material comprises material used to make a primary or secondary battery electrode; the substrate is a current collector; and the dried slurry on the substrate is an electrode.

12. The method of claim 1 , wherein the conductive layered assembly is incorporated in a primary battery, a secondary battery, a capacitor, a supercapacitor, a capacitor-battery hybrid, a hybrid capacitor, an asymmetric supercapacitor or a psuedocapacitor.

13. The method of claim 1 , wherein: the dry, powdered active material comprises an electrolyte material; and the dried slurry on the substrate is an electrolyte.

14. The method of claim 1 , wherein: the dry, powdered active material comprises an electrolyte material; the substrate is an electrode assembly comprising an electrode applied to the conductive foil; and the slurry is applied to the electrode.

15. The method of claim 1 , wherein: a majority by weight of the dry, powdered active material comprises particles with sizes between a lower limit of 0.001 pm and an upper limit of 50pm; the conductive foil has a thickness between 4pm and 100pm; andthe mixture comprises, by weight:60-99% of the dry, powdered active material;1-15% of the binder;0-5% of functional additives; and0-20% of a conductive additive having a particle size between 1nm and 1 pm.

16. The method of claim 1 , wherein the mixture comprises, by weight:75-97% of the dry, powdered active material, wherein the dry, powdered active material is activated carbon;3-15% of the binder;0-5% of functional additives; and0-5% of a conductive additive.

17. The method of claim 1 , wherein the mixture comprises, by weight:60-98% of the dry, powdered active material, wherein the dry, powdered active material is battery material;1-10% of the binder;0-5% of functional additives;1-20% of a conductive additive; and 0-5% of electrolyte material.

18. The method of claim 1 , wherein the mixture comprises, by weight:85-99% of the dry, powdered active material, wherein the dry, powdered active material is electrolyte material;1-10% of the binder;0-5% of functional additives.

19. The method of claim 1 , wherein the step of applying the slurry comprises: nebulizing the slurry; and electrostatically charging the nebulized slurry.

20. The method of claim 1 , wherein the step of applying the slurry comprises:spraying the slurry onto the substrate; and spreading the slurry on the substrate with a doctor blade.

21. The method of claim 1 further comprising, during, before or after the first mixing step, electrostatically charging the dry, powdered active material, the binder or both the dry, powdered active material and the binder.

22. The method of claim 1 , wherein: the dry, powdered active material comprises activated carbon; the mixture further comprises carbon black; and the binder is PTFE (polytetrafluoroethylene).

23. The method of claim 1 , wherein the conductive foil is a current collector, the method further comprising priming a surface of the conductive foil by: applying more of the binder to the surface; applying more of the liquid to the surface; applying another binder to the surface; applying a conductive additive to the surface; applying an adhesive to the surface; applying a solvent to the surface; cleaning the surface; heating the surface; etching the surface; anodizing the surface; removing traces of oil from the surface; or any combination selected therefrom.

24. The method of claim 1 , wherein the slurry comprises 1 g of the mixture for every 1-20ml of the liquid in the slurry.

25. The method of claim 1 , wherein the liquid is water, ethanol, methanol, isopropyl alcohol, propanol, n-butanol, N-methylpyrrolidone or any combination selected therefrom.

26. The method of claim 1 , wherein the energy storage device may include one or more anode layers, one or more cathode layers, one or more electrolyte layers or any combination thereof to form a layered assembly.

27. A conductive layered assembly made by: mixing dry, powdered active material with a binder to form a mixture; fibrillating the mixture to obtain a partially to fully fibri Hated mixture; mixing the partially to fully fi bri Hated mixture with a liquid to form a slurry; applying the slurry to a substrate comprising a conductive foil; and drying the slurry on the substrate to form the conductive layered assembly.

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