Method for producing highly activated, monolithic mesh biochar electrodes

Abstract

A method of manufacturing a highly activated, highly porous, highly conductive networked monolithic electrode for an electrical energy storage device, including a supercapacitor, pseudocapacitor, battery, or for an electrical power generation device, such as a fuel-cell, or for a gas production device, such as a hydrogen gas generator or an oxygen gas generator.

Description

[0001] BACKGROUND

[0002] 1. Cross Reference to Related Applications

[0003] This application claims the priority benefit of provisional application entitled "Process for Producing a High Activated, Monolithic Net-Shaped Biomass Electrode for Use in an Ultracapacitor, Pseudo-Capacitor, Battery or Fuel-Cell" and filed on March 29, 2019, and assigned serial number 62 / 826,005. The entire contents of the above-identified provisional application are hereby incorporated by reference. SUMMARY

[0004] The present disclosure relates to a method of manufacturing electrodes for energy storage devices, power generation, and hydrogen and oxygen production, wherein the method comprises formulating a favorable composite biomass mixture, impregnating the biomass with a pre-activating agent and / or a precursor, casting or molding the impregnated biomass mixture to form pre-net-shaped monolithic biomass wafers or pellets (hereinafter "wafers"), and carbonizing the wafers in a furnace to produce net-shaped conductive monolithic carbonaceous biochar electrodes with graded pores and channels. The present disclosure further relates to the use of monolithic electrodes manufactured according to the disclosed method in ultracapacitors, pseudo-capacitors, batteries and fuel cells, and electrolysis-based gas generators. The "uncarbonized" biomass processing and pre-net-shaping into precursor wafers does not use adhesives. The pre-net-shaped monolithic wafers are subsequently carbonized at high temperatures, wherein their dimensions are reduced to yield monolithic net-shaped high surface area activated biochar carbon electrodes containing graded channels and pores. The manufacturing of the biomass-derived carbonaceous monolithic electrodes does not use adhesives. These net-shaped biochar monolithic electrodes can be further shaped and activated before final assembly into ultracapacitors, pseudo-capacitors, batteries or fuel cells or used as electrodes in electrolysis-based gas generators for the production of hydrogen and / or the production of oxygen.

[0005] 3. BACKGROUND

[0006] As global energy consumption and demand increase, the demand for renewable, sustainable and clean energy sources, as well as novel, versatile and scalable energy storage systems, is also increasing. For electrical storage in particular, batteries have become the focus due to their high energy density for electrical storage capabilities. However, supercapacitors and pseudocapacitors have proven to be promising electrochemical energy storage devices due to their high power density, low cost, excellent charge and discharge capabilities, long cycle life and environmental benefits. Fuel cells do not store electrical energy, but instead provide an energy-efficient method of converting the chemically stored energy in hydrogen and hydrocarbon fuels directly into electrical energy on and within the electrodes. The use of fuel cells to generate electricity contrasts with the use of burning fuel to generate steam for subsequent turbine generation, which is typical of conventional power plants.

[0007] Batteries have traditionally been used extensively in many applications in our daily lives. However, batteries have many limitations that restrict their widespread applicability as sustainable energy storage devices. For example, widespread use of batteries in cellular devices or automobiles requires large amounts of lithium, nickel, manganese, and cobalt, each of which needs to be harvested from the Earth, depleting reserves of these natural metals. Since these materials are non-renewable after extraction, their sustainability is very limited. As the demand for these non-renewable metals increases, their price also increases. There has been some success in recovering these specific lithium battery-related materials from spent batteries, but there are many challenges in terms of cost and re-purification.

[0008] As disclosed herein, in contrast to their battery counterparts, supercapacitors and pseudocapacitors can be made with electrodes made from renewable resources, such as biomass materials (e.g., wood, grass, other plants), which makes them lower cost and more environmentally friendly than conventional alkaline or lithium-ion batteries. In addition, supercapacitors have the ability to charge and discharge at faster rates and have longer life cycles with minimal degradation compared to batteries because energy is stored electrostatically in supercapacitors and pseudocapacitors, rather than chemically as in battery technology. Rapid charge and discharge and a greater number of life cycles enable supercapacitors to work better, last longer, and provide utility in other applications that require such functionality. The main disadvantage of conventional supercapacitors is their much lower energy density, which is typically 20:1 or worse for supercapacitors compared to lithium-ion batteries.

[0009] Pseudocapacitors can be simply described as a hybrid of supercapacitors and batteries. As mentioned above, supercapacitors store electrical energy in a static manner, while batteries store electrical energy in a chemical manner. Pseudocapacitors can use similar electrodes and ion transport mechanisms as supercapacitors, but when the migrating charged ions transport electrical energy to the opposite polarity electrode, the ions bind to specific sites on the surface of the pseudocapacitor electrode through weak chemical bonds or redox reactions, somewhat mimicking the chemical-based charge storage mechanism of batteries. This provides the pseudocapacitor with higher energy storage capacity than the direct method used in standard design supercapacitors, and results in an increase in the energy storage density of the pseudocapacitor to exceed that of its supercapacitor counterpart and approach that of a battery. One drawback is that this method reduces the power density of the pseudocapacitor (the rate at which it can discharge electrical energy) to much less than the high power density supercapacitor performance described above. Thus, the performance of the pseudocapacitor is more like that of a battery. Furthermore, the chemical reaction mechanism used in pseudocapacitors uses metals, such as manganese, iron, or other metals and alloys, to facilitate this electrical energy storage, thus requiring non-renewable manufacturing methods and resulting in a reduced number of device life cycles.

[0010] Fuel cells convert a fuel feedstock, most commonly hydrogen gas, into a chemical reaction inside, on the surface of, and in the electrodes, which outputs electricity. The most common fuel cell is the proton exchange membrane (PEM) fuel cell. This type of cell takes in hydrogen and oxygen (or air), performs an internal reaction on a membrane and conductive electrodes, and forms water and electricity. Maintaining the operation of these PEM fuel cells presents complexities and difficulties. The methods disclosed herein describe the production of stable, monolithic, carbon-based electrodes based on biochar that can be deployed in the PEM fuel cell or other fuel type fuel cell feed.

[0011] In addition to the electrical energy storage discussed above, there is also a demand for high-grade hydrogen gas to be used as a clean fuel for engines and the PEM hydrogen fuel cells described above. The methods disclosed herein describe the production of stable, monolithic, and highly porous electrodes based on biochar that can be used in a water electrolysis system to directly produce hydrogen and oxygen gases that can be directly fed into a PEM hydrogen fuel cell. Alternatively, the hydrogen and oxygen gases produced by electrolyzing water can be stored or transported for later use in a PEM hydrogen fuel cell to produce clean electricity with only water vapor as an exhaust byproduct. Still further, the hydrogen and oxygen gases can be combusted in an engine to obtain clean, non-CO2-based power, again with only water vapor as an exhaust byproduct.

[0012] The disclosure herein is generally applicable to all kinds of supercapacitors, pseudocapacitors, batteries, and fuel cells, or for use as electrodes in water electrolysis-based gas generators for hydrogen and / or oxygen production, because the electrode devices themselves have broad applicability when such electrodes are produced by the disclosed methods. For simplicity, we will hereinafter refer to supercapacitors as one of the final products comprising electrodes produced by the disclosed methods, as supercapacitors have the greatest performance improvements achieved by the disclosed invention, and other types of devices (e.g., pseudocapacitors, batteries, or fuel cells) are also suitable candidates for improvement using the products of the disclosed methods; however, all referenced electrical energy storage and conversion devices include, embody, and claim improvements by the methods of the present invention, as further described herein (including in the illustrative examples listed below).

[0013] The increased interest in supercapacitor technology is primarily focused on the development of electrode materials, as they are the primary determinant of supercapacitor performance. Porous carbon materials are widely used as supercapacitor electrode materials due to their high surface area and excellent electrical conductivity. Most research focuses on developing highly porous activated carbon materials with good electrical conductivity by using cost-effective biomaterials. These research groups and manufacturers create electrodes by combining activated carbon granules, powder, or dust with a binder. The mixture is then spread onto a current collector sheet, typically a thin foil such as aluminum, stainless steel, or titanium foil. Most activated carbon electrodes are made by carbonizing carbon source precursors such as tar pitch, sawdust, carbon-based polymer powders, coal, coke, petroleum coke, graphite materials, or biomass. These precursors are carbonized at high temperatures in a furnace to form activated carbon powder or dust. This carbonization step is typically followed by post-carbonization activation to form the activated carbon powder or dust, using strong acids, strong acids, or bases for demineralization and carbon dioxide gas or steam for pore generation. Typically, after one or more of these activation steps, the activated carbon powder or dust is mixed with a binder (up to 66% by weight compared to the activated carbon material) to form a slurry or paste-like substance for laminating, coating, pasting, or printing the slurry or finely powdered activated carbon material as a very thin layer (typically less than 200 microns thick) onto a current collector foil. Additional methods, such as electrophoresis, are used to bond the activated carbonaceous material to the foil current collector. Notably, this carbon-foil interface presents issues with conductivity, adhesion, and corrosion.

[0014] While the methods mentioned by others may be effective, these other approaches certainly have their drawbacks. For example, the addition of a binder can clog the channels and pores of the activated carbon material, which can reduce the effectiveness of the activated carbon and dilute the overall carbon content in the finished electrode. Furthermore, this manufacturing method is limited to printing or coating very thin layers of activated carbon material onto the current collector, resulting in poor conductivity and volume utilization of the final product, as well as high packaging overhead for the final device. The adhesion of the thin layer of activated carbon material can also fail or degrade.

[0015] The disclosed invention described herein utilizes an advantageous reticulated forming process that results in a product that is a thick, highly porous activated carbon monolithic electrode with hierarchical pores and channels, having a high internal surface area and high volumetric capacity, without the need for the additional use of binders that otherwise hold the activated carbon particles together. Thus, the disclosed method improves the overall efficiency of the produced monolithic electrode and minimizes packaging overhead for the assembled final product. Furthermore, the disclosed method avoids the production of dusty powdered activated carbon that would subsequently require bonding and dilution, and which would reduce the desired electrical and physical properties. Summary of the Invention

[0016] The present invention discloses a method for making a reticulated, high surface area active monolithic carbon electrode from a self-bonded pre-reticulated biomass material. Due to the self-bonding properties of the biomass material treated herein, no chemical adhesive is required. More specifically, the present disclosure relates to a method for making a thick reticulated activated carbon electrode monolith, which provides advantages in the design and manufacture of supercapacitors, pseudocapacitors, batteries and fuel cells, or is used as an electrode in a water electrolysis-based gas generator that produces hydrogen and / or produces oxygen, with much lower packaging overhead, thereby allowing more electrode material to be attached to each current collector (foil). This greatly increases the electrode mass and volume ratio in the entire final product.

[0017] More specifically, the present disclosure provides a method for formulating and adjusting the properties of electrode wafers derived from biomass through a series of steps, such as selecting biomass materials and optionally pre-treating the biomass. As disclosed in U.S. Patent Nos. 9,478,324 and 10,121,563 by Favetta et al., exemplary pre-treatments may include one or more of: (i) washing, retting, chemically treating, demineralizing, and drying the biomass, (ii) grinding the biomass to a desired size, texture, friability, and adsorption, (iii) mixing biomass of different plant origins and different grind sizes / textures / friability / adsorption to achieve graded component particle size and porosity, (iv) adding compatible solids or liquids that are not adhesives to promote softening and self-adhesion of the biomass, and / or (v) pre-reticulating the wet biomass mixture by pressing, optionally heating or baking, to form self-bonded biomass wafers that are precursors to biochar electrodes.

[0018] Furthermore, the present disclosure provides a method for carbonizing pre-reticulated biomass wafers in a high temperature furnace and optionally further activating self-bonded carbonized electrodes derived from biomass to produce thick, highly porous and activated reticulated biochar electrode monolithic wafers for use in supercapacitors, pseudocapacitors, batteries and electric fuel cells, or as electrodes in water electrolysis-based gas generators that produce hydrogen and / or oxygen.

[0019] Additional features, benefits, and applications of the disclosed method will be apparent from the following detailed description, particularly when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To assist one of ordinary skill in the art in practicing the disclosed method, reference is made to the accompanying drawings.

[0021] Figure 1 is a schematic flow chart of an exemplary processing scheme for grinding, mixing, pre-meshing, hot pressing, carbonization, and extraction of carbonaceous monolithic biochar electrodes according to the present disclosure.

[0022] Figure 2 is a schematic flow chart providing a more detailed description of the preparation of a clean molded plate system according to the present disclosure.

[0023] Figure 3 is a schematic flow chart providing a more detailed description showing the disassembly of a pressed, heated, and baked molded plate assembly according to the present disclosure.

[0024] Figure 3A is a schematic flow chart providing a depiction of washing / cleaning steps according to the present disclosure.

[0025] Figure 4 is an exploded schematic diagram of an exemplary ultracapacitor according to the present disclosure.

[0026] Figure 5 is a schematic cross-sectional view of carbonaceous monolithic biochar electrodes assembled into a stack according to the present disclosure.

[0027] Figure 6 is a photograph of an actual terminal device (sawn in half by mechanical means) fabricated and assembled according to the disclosed method to provide electrical storage from a supercapacitor device at 12 volts DC.

[0028] Figure 7 is a scanning electron microscope (hereinafter referred to as SEM) image of a biochar wafer carbonized according to the present disclosure without using the disclosed degassing screen at a magnification of 40,480 times.

[0029] Figure 8is a SEM image (260,000x) of a biochar wafer carbonized using the disclosed degassing mesh according to the present disclosure and showing observable pores and channels that provide excellent activation for electrical storage.

[0030] Figure 9 Two (2) SEM images of biochar wafers gas activated with CO2 at elevated temperature and using the disclosed degassing screen are provided at 166,790x magnification (FIB magnification of 1,000x) and 167,080x magnification (FIB magnification of 167,080x), respectively. DETAILED DESCRIPTION

[0031] The present disclosure will now be described with reference to exemplary embodiments. It will be understood by those skilled in the art that the present disclosure is not limited to the specific embodiments disclosed herein, but is susceptible to modification, variation, and / or improvement based on the disclosure provided herein. The present disclosure expressly contemplates such modifications, variations, and / or improvements as would be apparent to those skilled in the art based on the disclosure set forth herein.

[0032] Discussion of the Drawings

[0033] As mentioned above, Figure 1 is a schematic flow chart (100) of an exemplary processing scheme for grinding, mixing, pre-meshing, hot pressing, carbonization, and extraction of carbonaceous monolithic biochar electrodes according to the present disclosure, including the following elements:

[0034] 50 Biomass selected for larger particle size grinds

[0035] 55 Biomass grinder configured for larger sized grinds.

[0036] 104Ground biomass large particles

[0037] 60 Biomass selected for smaller object size grinds

[0038] 65 Biomass grinder configured for smaller sized grinds.

[0039] 105 ground biomass small particles

[0040] 110 dry biomass mixtures of various selected particle sizes and mixtures

[0041] 120 Mixing container for mixing biomass particles of different sizes

[0042] 112 Container containing preactivator and / or precursor

[0043] 114 Preactivating agent and / or precursor in container 112

[0044] 115 The desired biomass mixture (110) and the preactivating agent and precursor (114) are mixed in 120

[0045] 130 Cleaning the molded plate assembly, further depicting the biomass mixture / preactivator / precursor placed in the cavity on the molded plate assembly

[0046] 140 Cleaning Hot Pressing System

[0047] 141 Clean the top hot plate of 140

[0048] 142 Clean the bottom hot plate of 140

[0049] A heated molding process of 144 (140) is applied to the molding plate assembly (130), including the manipulation of the biomass / precursor mixture (115) prepared within (13), thereby forming a pre-reticulated biomass wafer (150). This molding baking process causes some of the pre-activator / precursor (114) to seep onto the plate system (130) and the heated plates of the presses (141) and (142), thereby making them soiled / dirty and converting them to (146) and (147), respectively. The pressure applied by the molding system 145 is then released to allow extraction of the soiled / dirty molding plate (330) containing the baked pre-reticulated biomass wafer (150).

[0050] 145 Dirty / Soiled Heated Moulded Panel Systems (140)

[0051] Dirty / stained top heat platen of 146 145

[0052] 147 145 Dirty / dirty bottom heat press plate

[0053] 149 Cleaning process for cleaning a dirty / dirty moulding oven machine (145) to restore it to a clean and usable condition (140)

[0054] 150 Pre-reticulated biomass wafer extracted from the die plate system, having been removed from (130), where (130) is now described as a dirty / dirty die plate system (330), with further details regarding disassembly and removal being provided in Figure 3 (300) and Figure 3A Provided in (350).

[0055] 160 high temperature carbonization furnace system.

[0056] Removable bottom support plate for 162 furnace system

[0057] 164 bottom screen between the bottom tray and the pre-meshed biomass wafer.

[0058] 166 top counterweight

[0059] 168 Top screen on pre-meshed biomass wafer and below top weight

[0060] 170 Carbonized monolithic carbon biochar electrode

[0061] Figure 2 is a schematic flow chart (200) providing a more detailed depiction of the preparation of a clean molded plate system according to the present disclosure, including the following elements:

[0062] 200 - A flow chart outlining the preparation of a clean mold plate system (130), its assembly, and the addition of prepared biomaterial (115) thereto, the mold plate system consisting of parts 231, 232, 233, 235, 236, 237, and other components further described below.

[0063] 321-Base plate of molded assembly

[0064] 232 - A center formed die plate with a slotted or cylindrical hole that forms the cavity when attached and secured to 231.

[0065] 233-Top plate of molded assembly

[0066] 235 - Fastener used for assembly, attaching and securing 231 and 232 together.

[0067] 236 - Cylindrical block press insert that presses the biomass mixture (115) into the cavity of subassembly 239.

[0068] 237 - Wetted The cylindrical block insert (236) is now wetted with a non-stick lubricating release agent 242, described further below.

[0069] The subassemblies 239-231, 232, 235, add the biomass mix mixture (115) into the subassembly cavity and then press it into the cavity using (237) these subassembly parts which have been lubricated with release material 242.

[0070] 240 - Container containing mold release lubricant 242.

[0071] 242 - Mold release lubricant is used to wet all parts of the subassembly 239 to prevent sticking 115 when pressed in the heated molding press 140.

[0072] Figure 3is a schematic flow chart providing a more detailed depiction showing the disassembly of a pressed, heated and baked molded plate assembly according to the present disclosure, including the following elements:

[0073] Flowchart 300 shows the disassembly of 330, which is the pressed, heated and baked die plate component (130) which is subsequently pressed and baked in (140) and (145) and contains a pre-reticulated biomass wafer (150), further showing the die plate system parts and components previously referred to as clean parts 231, 232, 233, 235, 236, 237, now referred to as dirty / dirty parts of the die plate system and renumbered as 331, 332, 333, 335, 336, 337.

[0074] 330 - Baking the molded assembly containing the pre-reticulated biomass wafer within the cavity of the mold plate system; additionally, causing the surface of the mold plate assembly to become dirty and stained.

[0075] 333-Remove the dirty top plate from the 330 assembly.

[0076] 331 - Dirty bottom press plate of a die plate system, further showing the reticulated biomass wafer (150) obtained beneath the dirty press slug (336).

[0077] 332 - Dirty center panel of a molded panel system.

[0078] 335-Removed, dirty fasteners of molded panel systems.

[0079] 336 - Dirty compact removed from the chamber of 332 and subsequently separated from the pre-netted biomass wafer (150)

[0080] 339 - Still assembled subassembly of the molded panel system, with the cover (333) removed.

[0081] 350-cleaning steps 331, 332, 333, 335, 336, thereby restoring them to the state in Figure 2 Parts 231, 232, 233, 235, 236 used in the steps and processes depicted.

[0082] Figure 3A is a schematic flow chart (355) providing a depiction of the washing / cleaning steps according to the present disclosure, including the following elements:

[0083] Flowchart 355 shows the washing / cleaning steps of parts 331 , 332 , 333 , 335 , 336 , thereby converting them back into clean mold plate components 231 , 232 , 233 , 235 , 236 .

[0084] Figure 4 is an exploded schematic of an exemplary supercapacitor (400) according to the present disclosure, comprising the following elements:

[0085] 400 - exploded schematic of an exemplary supercapacitor according to the present disclosure comprising 410, (440) and (460).

[0086] 410 - process of wetting the dry carbonaceous monolithic biochar electrode (170) and the non-conductive porous separator with electrolyte (414) from a container (412)

[0087] 412 - container holding electrolyte (414)

[0088] 414 - electrolyte used in the assembly of embodiments of electrodes disclosed herein to make the final product energy storage device (440)

[0089] 175 - dry non-conductive porous separator

[0090] 428 - electrode (170) that has been wetted with electrolyte (414) then used as the specific electrode for a given voltage polarity, opposite to the polarity applied to (430)

[0091] 429 - conductive glue or epoxy used to affix and adhere (428) and (430) to (424)

[0092] 430 - electrode (170) that has been wetted with electrolyte (414) then used as the specific electrode for a given voltage polarity, opposite to the polarity applied to (428)

[0093] 432 - separator (175) wetted with electrolyte (414)

[0094] 440 - exploded schematic of an exemplary supercapacitor according to the present disclosure showing the detailed assembly sequence of each component on the final embodiment energy storage device

[0095] 422 - non-conductive end compression plates used to compress and hold the energy storage device together.

[0096] 424 - conductive charge collector

[0097] 426 - non-conductive elastomeric seal such as the O-ring shown.

[0098] 428 - top mesh monolithic biochar electrode with electrolyte (414) on and inside, made by the methods disclosed herein.

[0099] 430 - bottom mesh monolithic biochar electrode with electrolyte (414) on and inside, made by the methods disclosed herein.

[0100] 432 - A non-conductive and porous membrane separator in (410) with electrolyte (414) applied thereto, placed between (408) and (410) and sealed by (406).

[0101] 440 is a schematic diagram of a compressed and assembled side view of an exemplary supercapacitor according to the present disclosure, showing the detailed assembly sequence of each component on the final embodiment power storage device

[0102] Figure 5 is a schematic cross-sectional view of a carbonaceous monolithic biochar electrode assembled into a stack according to the present disclosure, comprising the following elements:

[0103] 500 depicts a diagrammatic assembly of an embodiment of carbonaceous monolithic biochar electrodes (428) and (430) assembled into a stack, thereby allowing each of the voltage potentials stored within such a pair of electrodes (428) and (430), respectively, to be added in a final device embodiment to produce a fully contained final device that can charge, store and deliver any desired voltage, as well as the final device produced by the present disclosure, and is not limited by the voltage operating window of the electrolyte.

[0104] Figure 6 is a photograph (600) of an actual final device (sawn in half by mechanical means) manufactured by the disclosed method and assembled according to (500) to provide electrical storage from a supercapacitor device at 12 volts DC.

[0105] Figure 7 The following is an SEM image of a biochar wafer carbonized according to the present disclosure without using the disclosed degassing screen at 40,480 times magnification:

[0106] Scanning electron microscopy image of a biochar wafer 710 that was carbonized without the disclosed degassing screens (164) and (168); notably, the image of (710) shows a visible coating of tar and caramel that blocks the pores and channels. The SEM image providing the magnification data for the sample is 40,480x.

[0107] Figure 8 is an SEM image (260,000x) of a biochar wafer carbonized using the disclosed degassing screen according to the present disclosure, and showing observable pores and channels that provide excellent activation for electrical storage.

[0108] 800 shows an SEM image 810 of a biochar wafer that was carbonized using the disclosed degassing screens (164) and (168); notably, image 810 shows observable pores and channels that provide excellent activation for electrical storage. The SEM image providing the sample magnification data is 260,000 times

[0109] Figure 9 Two (2) SEM images (900) of biochar wafers gas activated with CO2 at elevated temperature and using the disclosed degassing screen are provided at 166,790x magnification (FIB magnification of 1,000x) and 167,080x magnification (FIB magnification of 264,000x), respectively.

[0110] Image 910 of a biochar wafer gas-activated with CO2 at elevated temperature using the disclosed degassing mesh. SEM data further shows sample 910 at a magnification of 166,790x and FIB at a magnification of 1,000x. Notably, sample 910 exhibits observable hierarchical pores and channels, which provide excellent activation for electrical storage.

[0111] 920 is an image of a biochar wafer gas-activated at elevated temperatures using steam and the disclosed degassing mesh. The SEM data further shows sample 910 at a magnification of 167,080x and FIB at a magnification of 264,000x. Notably, sample 920 displays observable hierarchical pores and channels, which provide excellent activation for electrical storage.

[0112] Establishment and "tuning" of material properties of pre-reticulated biomass pellets:

[0113] Biomass selection and pretreatment:

[0114] The selection of the biomass source plant species, agronomic selection, harvesting method and timing, pretreatment of the harvested biomass with cleaning, retting, chemical treatment, demineralization, and drying of the biomass feedstock are all key factors in producing superior electrodes according to the disclosed methods. Applicants incorporate by reference two (2) previously issued U.S. patents to Favetta et al., namely, U.S. Patent Nos. 9,478,324 and 10,121,563, which provide teachings related to, among other things, biomass selection and pretreatment. The entire disclosures of the '324 and '563 patents are incorporated herein by reference.

[0115] Biomass grinding promotes the production of pre-netted wafers

[0116] The biomass material (cleaned / dried from the above sources) is ground to produce biomass particles processed into a set of desired particle sizes, textures, friability and adsorbability ranges, which are used as precursors to generate a hierarchical pore structure in the electrode once it is carbonized. In the disclosed method, a range of methods (including the use of consumer-grade coffee grinders and precision Retch ZM-200 laboratory grinders with variable speeds up to 18,000 RPM), cutting rotors, and screen types and sizes can be used to produce biomass grinding, as described in detail in the Examples and Control Examples section below. However, any effective grinding method can be used, including instruments such as consumer-grade coffee grinders, industrial grinders, chainsaws, chippers, hedge trimmers, roller mills, ball mills, hammer mills, etc. Therefore, the present disclosure contemplates the use of any cutting or chopping device that can be used to deliver the desired particle size, texture, friability and adsorbability. For a given grinding step or particle size requirement, this series of devices may be alternatives (one or the other may suffice), or such devices may be tailored to meet specific requirements, such as a specific rotary hammer mill blade size or profile size with a screen size, a specific toothed rotor and cutting screen or cutting screen size, or other specific combinations, based on the particle distribution and mix of the grind size, and therefore the final electrode properties that need to be achieved.

[0117] The particle size and "fluffiness" of the biomass particles are important factors influencing and controlling the self-bonding of the intermediate pre-reticulated biomass wafers, the detachment of the wafers from the process equipment, and the non-sticking to the process equipment, and are also important for the performance of the carbonized electrode in the final product. In addition, these same starting characteristics are important for the compatibility of the obtained carbonized electrode with additional activation steps after carbonization, as well as the electrical storage performance, fuel cell conversion performance, or water electrolysis-driven H2 / O2 gas generator of the final monolithic electrode product produced according to the method.

[0118] The biomass grinding methods disclosed above can be used in accordance with the present invention to produce particles that may be described as "coarse" (i.e., wherein the majority of particles are approximately 1 mm x 5 mm), "medium" (i.e., wherein the majority of particles are approximately 0.1 mm x 2 mm), and / or "fine" (i.e., wherein all particles are less than 0.25 mm in any dimension). Alternatively, a more controlled scientific grinding method can be used to produce a very narrow distribution of particle sizes, such as 500 μm, 200 μm, 120 μm, 80 μm, 25 μm, 20 μm, etc., produced by a specifically calibrated cutting screen or sieve device.

[0119] In the exemplary embodiments of the present disclosure, particle sizes less than 20 μm were not produced because the differences in the self-bonding properties of the pre-reticulated biomass wafers were indistinguishable when a biomass grind particle size well below 80 μm was included, and the carbonization and activation, as well as the electrical performance of the final electrode device, were not affected by variations in particle size below 80 μm. Actual results of these formulated mixtures are described in the Examples and Comparative Examples sections below.

[0120] ●The various biomass grinds and source materials disclosed above are then mixed to prepare a mixture for making the pre-reticulated biomass wafers according to the present disclosure. This mixing of various grind sizes and various biomass sources and materials is then carried out as an important method to adjust the final material properties and generate the hierarchical pore structure and self-binding properties of the biomass. Once the biomass grind mixture is prepared, it must be moistened with a compatible liquid to form a paste with a consistency similar to moist sawdust, until a fully wetted material, similar to cooked oatmeal. This added liquid is not a binder or adhesive for the biomass, but rather serves to soften the lignin, hemicellulose and cellulose surfaces and the fluffy fiber extensions of the ground biomass, causing these biomass components to have open chemical bonds and be partially dissolved. When the biomass is baked in the initial oven pressing step, these chemically opened bonds and fibrils then cause the biomass surface and fiber extensions to self-bind. These liquid additives are either pressed out and leak out of the biomass pre-reticulated molded system, evaporate from it, or participate in the organic polymerization of the biomass without being cast as a binder, but can act as a copolymer, depending on the chemical reaction, as further described below.

[0121] It is recommended to mix two or more biomass feedstocks or particle sizes in specific mass ratios, such as 50% "medium" plus 50% fine, or 50% "medium" plus 25% "fine" plus 25% 80 μm. These exemplary mixtures are merely illustrative of the formulations (and are not limiting), and actual examples of good and bad biomass mixing are disclosed in the Examples and Comparative Examples sections below.

[0122] ○ In addition, the biomass source for a particular particle grind size must be considered in order to introduce the appropriate amount of lignin to hemicellulose, lignin to cellulose, lignin to other organic compounds (such as sugars, polysaccharides, tars, natural oil compounds, isoprene, terpenes and their higher polymers, including sesquiterpenes, as well as naturally derived or added chemicals, minerals, metals, etc.) into the final biomass mixture. Further mineral components are removed or added during pre-reticulation molding during the preparation and mixing of the biomass grinds, or during the previous washing and pretreatment steps described above. Further relevant teachings are provided in the '324 and '563 patents previously incorporated herein by reference. The above considerations have additional implications for the natural self-association of the biomass and in situ activation in the furnace during the high temperature carbonization or high temperature post-carbonization steps described below.

[0123] The mixing of two or more biomass materials of different particle sizes and biomass origins, and the additional wetting with a liquid activator, precursor material, and self-polymerizing compound of the biomass, allows the prepared biomass grind mixture to strengthen itself and bind the biomass particles together during the initial pressing-baking step in the hot press. As applied to the concept of the biomass mixture, the finer particles and fluffy fibrils (e.g., "fine" or 80 μm particles) of the biomass activated by the self-binding precursor agent act primarily as natural self-binding bridges and as natural self-adhesives in the biomass to hold together the longer, higher aspect ratio medium and coarse grind biomass materials, thereby forming a final web-shaped wafer with excellent physical and mechanical properties. The difference between this disclosed method of pre-reticulated biomass monolithic wafer and other methods using binders is that all the obtained components used in the disclosed method are biomass and are of organic origin when intact, with almost no residual polymeric or self-bonding precursor materials, and any such residual precursor polymers and activators are further removed in subsequent steps, so that the final product of the self-bonded monolithic biochar electrode has excellent electrical and physical properties after high-temperature carbonization in the furnace, high-temperature activation and other post-carbonization activation steps. It is these excellent physical and mechanical properties that enable the pre-reticulated biomass wafer prepared according to the disclosed method to withstand the harsh carbonization conversion into biochar monolithic wafer electrodes, and enable the obtained biochar monolithic wafer electrodes to withstand the harsh in-situ co-carbonization and activation, or post-carbonization activation further disclosed below.

[0124] The mass ratio of Biomass #1 (higher aspect ratio, larger size particles) to Biomass #2 (lower aspect ratio, smaller size particles) is typically between 1 : 10 to 10: 1. This ratio is measured on a dry basis (about 10% moisture) and on an absolutely dry basis (moisture less than 1%) of the biomass, and where the moisture content should be measured to compensate for the net mass of the actual biomass, as well as the in situ moisture content of the dilution added activator and precursor liquids, which should be compensated for in the dilution, concentration, and amount added to the biomass mixture of the activator and precursor liquids in making. Minor / subtle changes in biomass mass, moisture, and liquid concentration and amount added are tolerable, but care should be taken to maintain accuracy and proper performance of the biomass self-binding.

[0125] • Third, fourth, etc. additional biomass components of particle size, plant origin, and pretreatment can be used to further control and enhance the physical and chemical properties of the pre-reticulated biomass wafer, resulting in the physical, chemical, and electrical properties of the final reticulated carbonized thick monolithic biochar electrode element. These other additives and adhesion through finer, softer, smaller biomass ground particle sizes to the basic "scaffolding" of the larger biomass ground particles play a role in enhancing the final product reticulated monolithic biochar electrode and help facilitate electrical or physical enhancements, such as during furnace carbonization, such as during post-carbonization high temperature activation, such as through other methods (e.g., in Applicant's concurrently filed entitled "Process for Producing Highly Activated Electrode Through Electro-Activation", Serial Number PCT / US 2020 / 025648, which is incorporated herein by reference).

[0126] • In experiments and development, the dry mass loading of the biomass ranges from 0.1 g to 10 g per wafer; however, this mass loading is limited only by the size of the experimental molds and templates made for this purpose, and is an extensive property of the product. Further, to facilitate the manufacture of these molded parts, the mold plates, cavities, and press blocks are shaped as matching cylindrical blocks, resulting in pre-reticulated wafers in the form of cylindrical blocks, whereby the reticulated monolithic biochar electrode is in the shape of a cylindrical block. Any matching cavity and press block can be used in the examples, such as ovoid, such as elliptical, such as square, such as rectangular, such as any polygon, and can also not be planar or flat, but can also be curved, such as saddled, such as cupped, as set forth in the '324 and '563 patents previously incorporated herein by reference.

[0127] • Any size and shape can be used and are encompassed in the disclosure herein. The liquid to biomass ratio ranges from 0.05 to 10 milliliters per gram of biomass (dry basis), which is an important intrinsic property of the product and end product electrode manufacturing process, and is relevant.

[0128] • The density of the wetted pre-reticulated biomass wafer can range from 0.5 grams per cubic centimeter to 4 grams per cubic centimeter. This is a controllable property based on the following: the proportions of fine, medium, coarse biomass mixtures, friability, loft of each biomass grind, specific biomass plant source, activator / precursor liquid loading in the biomass, and additions to the wetted biomass prior to baking into the pre-reticulated monolith, and baking pressure, time, and temperature.

[0129] • Selected agricultural products are used as inputs (e.g., yellowtop, reed, miscanthus, generic "oakwood", bamboo, coconut shell, nut shell, etc.). Additional information on agricultural input selection is set forth in the '324 and '563 patents previously incorporated by reference herein.

[0130] • The pre-reticulation of the biomass wafer is done without binders. Naturally occurring or simple compounds are used as self-binding precursors in a typically aqueous liquid solution, such as a protic acid, e.g., formic acid (found in ant saliva), acetic acid (vinegar), propionic acid, or alternatively, common salts, such as potassium hydroxide salts (lye), sodium hydroxide salts, potassium chloride (saltpeter), sodium chloride (sea salt), sodium carbonate, sodium bicarbonate, potassium carbonate, and / or potassium bicarbonate. These precursor compounds that facilitate self-binding of the biomass are used to soften and "attack" the existing chemical bonds and surfaces of the biomass cellulose, hemicellulose, and lignin when the biomass wafer is optionally wetted and heated during the press molding and low temperature baking process to form a reticulation, and then the biomass material recombines and rebinds to itself when the biomass wafer is baked in its pre-reticulated form in the heated press.

[0131] The temperature and time for the heat-molding process is typically in the range of 100°C to 250°C for 1 to 3 hours, depending on the planned target properties of the final product electrode, the biomass mixture formulation, the moisture of the raw biomass, and the loading and concentration of the solid or liquid activator used for self-binding. These solid or liquid activator compounds do not play a role in the binding of the biomass pellets after the pressing and baking steps are completed, but only facilitate the self-binding of the biomass during the early stage of the formation of the biomass wafer when baking in the hot press. While some of the compounds can remain in the baked biomass wafer after the baking process is completed, such as those found in solid form before dissolving in water, such as potassium hydroxide, potassium chloride, sodium hydroxide, sodium chloride, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, and / or other liquid compound components, such as formic acid, performic acid, acetic acid, peracetic acid, propionic acid, hydrogen peroxide solution, these liquid compounds are typically evaporated or reacted into the biomass material to form conjugate compounds of the raw biomass material or help the self-binding polymerization of the biomass during the baking process.

[0132] • Additionally, the disclosed method also involves impregnating the biomass mixture with a pre-activation agent to further enhance activation and increase the surface area of the resulting electrode after separate furnace carbonization, which is an additional high temperature step after the initial toasting of the initially pre-reticulated biomass low temperature toasting, and this carbonization is typically done in a separate high temperature carbonization furnace, as further described below. The impregnation step disclosed herein involves the addition of the aforementioned common salts, such as the cationic salts of the Group I and Group II alkali and alkaline earth metals of the Periodic Table of Elements, such as sodium, potassium, calcium, etc., and their anionic counterparts, such as hydroxides, chlorides, carbonates or bicarbonates, etc. These alkali (Group I and II) cations remain in the biomass wafer after the low temperature heated press toasting step, and then act as catalysts and activators when the pre-reticulated biomass wafer is high temperature carbonized in a high temperature separate carbonization furnace to form the desired reticulated biochar wafer electrode product, facilitating the chemical oxidation and chemical reduction functions to consume and / or catalyze the formation of CH4(methane), CO2(carbon dioxide), CO(carbon monoxide), and other carbon-containing gases, as set forth in the '324 and '563 patents previously incorporated by reference herein. The production of these gases in the furnace forms within the biochar carbon, and these gases escape from the biomass / biochar, thereby deoxidizing and dehydrolyzing the biomass material, and reducing the carbonaceous lignin, hemicellulose, and cellulose to pure carbon or near-pure carbon, as described in the '324 and '563 patents previously incorporated by reference herein. Additionally, as these gases escape, this creates pores in the biochar, thereby activating the biochar and making it suitable for use as an electrode in supercapacitors, pseudocapacitors, batteries, chemical / electricity fuel cells, and other adsorptive applications (such as liquid or gas purification, liquid or gas storage, hydrogen storage, water purification), or as an electrode in water electrolysis-based gas generators that produce hydrogen gas and / or produce oxygen gas, etc.

[0133] Pre-treatment - impregnation of biomass grind and mix with pre-activation enhancer;

[0134] ■ Pre-activation enhancers may be added to impregnate the internal structure of the biomass plant cells and to convert and / or remove unwanted components and for subsequent pore and channel activation. It should be noted that excessive amounts of these agents or excessively long contact times or high concentrations or temperatures can have adverse and deleterious effects on the biomass, leading to complete liquefaction of the biomass, destruction of the solid and fibrous structure of the biomass and loss of the advantageous physical and electrical properties of the final electrode monolith disclosed and claimed herein. The concentration of these solids or liquids, the mass ratio of these solids or liquids to the biomass, and the ratio of the biomass grinding (particle size distribution), the grinding mixture and the target biomass mixture itself, as well as the time and temperature of contact of the solids or liquids with the target biomass, will affect the performance of the biomass mixture when forming the pre-reticulated monolithic wafer in the hot press, and will affect the performance of the pre-reticulated monolithic wafer during the carbonization in the high temperature carbonization furnace and the final activation step of the biomass electrode wafer.

[0135] ○ The nature of the pre-activation enhancer can be acidic, basic or neutral:

[0136] ■ The biomass grind can be soaked in aqueous solutions of potassium hydroxide (KOH), potassium carbonate (KCO3), potassium bicarbonate (KHCO3), sodium hydroxide (NaOH), sodium carbonate (NaCO3), sodium bicarbonate (NaHCO3), or other similar common alkaline or neutral salt solutions, as well as any mixtures of such salts. These activators for self-binding tend to preferentially attack the hydroxyl groups on cellulose and hemicellulose, while having only some effect on attacking the biomass lignin, which is mainly based on carbon rings. In addition, these methods will cations (K + 、Na + , Ca ++ ) is impregnated into the biomass, which then promotes the creation and activation of biochar pores in the subsequent high-temperature furnace carbonization step. This basic or neutral salt additive option disclosed herein allows Group I or Group II cations (K + 、Na + , Ca ++ The addition of carbon to the biochar electrode (e.g., carbonyl groups, etc.) catalyzes the oxidation and reduction of carbon and carbon bonds of the biomass / biochar while undergoing high-temperature furnace carbonization, thereby creating hierarchical channels and pores in situ within the biochar electrode. A delicate balance of the amount of such Group I or Group II cations must be observed. This catalytic and carbon-carbon reaction of the Group I and Group II cations can weaken the carbonaceous scaffold structure of the biochar electrode, making the additional post-carbonization activation step slightly more challenging to avoid physical breakdown, but will create more favorable pores for ion transport into the electrode for electrical energy storage. These additives must be carefully mixed evenly into the biomass particle mixture to avoid uneven addition clumps and agglomerates, and the mixture must be observed before molding to detect whether the biomass has degraded to an undesirable, near-paste-like consistency.

[0137] ■ Aqueous solutions of hydrogen peroxide or acids such as formic acid, performic acid, acetic acid, peracetic acid, nitric acid, boric acid, or other protic or non-protic acids diluted in water to the disclosed concentrations can be added to the biomass mixture. This promotes the desired bonding by activating the biomass surface and / or participating in the polymerization of biomass self-association. This can be added to the biomass grind prior to final pre-reticulation in the press oven. These protic or non-protic or organic acids favor reactions with lignin and aromatic or carbocyclic structures and tend to enhance self-association via the lignin pathway, while the cellulosic reaction pathway predominates in the aforementioned salt or alkaline solution additions. These acids also further decompose cellulosic and hemicellulose structures, enabling these natural biomass compounds to recombine and polymerize during the formation of the pre-reticulated biomass wafers in the heated press oven and the subsequent high-temperature carbonization step. Compared to the alkaline or neutral salt addition methods also disclosed herein, the organic acid addition disclosed herein results in better biomass bonding, thus providing a more durable carbonaceous scaffold structure for the final biochar electrode. This then allows for a higher probability of success in obtaining a mechanically stronger final electrode product that can withstand multiple pore-generating activation steps, resulting in superior performance electrodes produced by this route.

[0138] ■ Hydrocarbon solvents, such as toluene, ethanol, and dimethylformamide (DMF), can also be added to the biomass grinding mixture before introduction into the biomass / chemical mixture to pre-activate the natural polymers (lignin, hemicellulose, cellulose) in the biomass, more specifically the fine and fluffy fibrils, by softening and / or dissolving a portion of these biomass compounds and causing them to reorganize and self-associate. Due to evaporation in the low-temperature die-pressing oven, these organic solvents generally do not remain in the final biomass pre-reticulated wafers, and further, any traces of such residual solvents remaining in the pre-reticulated wafers from the oven pressing are eliminated by evaporation during the early stages of heating in the high-temperature carbonization oven, before the actual final carbonization temperature and carbonization effect are reached.

[0139] Pre-activation enhancers can be solid or liquid. Thus far, in the disclosed methods, additive activators promoting biomass self-association have been described as typically liquid, though some reference to solid additives is possible. Other improvements to the disclosed methods have achieved good success by adding only solid activators, either in fine powder or crystalline solid form, to the biomass grind mixture during the preparation of the biomass material used to initially create pre-reticulated wafers in a heated press box. This addition of salt or acid in solid form takes advantage of the moisture content of the biomass and works well when the biomass moisture exceeds 15% by weight. It also contributes to the presence of adsorbed ambient moisture in the solid additive, which is common for compounds such as solid potassium hydroxide. Moisture further aids in solid ion dissociation, which is generated by the limited decomposition of the biomass, which results from the solids acting as hydroxyl radicals in the decomposing biomass and forming water. Care must be taken to ensure good mixing of the solids to ensure uniform incorporation into the biomass grind mixture, and because the transport of dissociated solid salts around and into the biomass material is slow, the contact time of the treatment is longer to promote chemical activation of the biomass self-association effect.

[0140] The mass ratio of biomass to preactivator is usually in the range of 1:10 to 10:1.

[0141] ● Alternatively, the biomass grind mixture can be treated with a removable templating agent (e.g., salt, wax, etc.) that can be removed by melting, washing, carbonizing, or burning or added to the pre-reticulated wafer, thereby using the template to introduce and cast controlled porosity into the pre-reticulated biomass wafer bulk structure and subsequent biochar electrode.

[0142] ● As disclosed in the '324 and '563 patents, raw or ground biomass can be "hydrothermally" treated under pressure at the gas / liquid interface of the biomass while submerged or wetted with a liquid to dissolve and selectively and controllably extract minerals from the biomass, or to partially or completely depolymerize the biomass to significantly increase the surface area and remove deleterious elements of the biomass (e.g., silica, metals, iron, etc.).

[0143] Pre-reticulation and pressing of mix into pellets or pellets:

[0144] • The '324 and '563 patents disclose the use of pre-treatment methods of biomass to influence or control web properties.

[0145] ●Optimize pressing time, formula, pressure and compression force to adjust material structure parameters.

[0146] o The low temperature oven pressing time when forming the pre-reticulated biomass wafers typically ranged from at least 45 minutes to a maximum of 180 minutes. Little benefit was achieved in testing when wafer bake times exceeding 180 minutes were used and the wafers became dry and brittle and weak.

[0147] ○ In a hot press, the pressure range of the heated mechanical press is generally 10,000 to 60,000 lbs, with consistent and excellent results when pressing at 30,000 lbs in a hot press. Since the actual pressure acting on the biomass mixture in a cylindrical die press is based on this pressure divided by the actual surface area of ​​the total number of press cylinders, the actual pressure for baking the biomass wafers in a heated press oven is as follows:

[0148] ■The circular area of ​​each cylinder bore and matching cylindrical pressing block used in the experiments was 1.25 square inches. The die plate system used for the experiments contained 16 cylindrical cavity holes. Therefore, a total biomass pressing area of ​​20 square inches was used. When the nominal hot press force of 30,000 pounds is divided by 20 square inches, the result is that the force applied when pressing and baking the biomass mixture into pre-reticulated biomass wafers in most experiments is 1,500 psi. There are many different embodiments, shapes, and numbers of cylindrical blocks, so the total force applied to the hot press will need to be adjusted for each wafer of the mold instrument. In addition, the size and number of holes, cylindrical blocks, and template dimensions are not limited to the specific embodiments disclosed above.

[0149] The pressing temperature and temperature cycles applied to the pre-reticulated biomass in the heated oven can be controlled to alter the properties of the pre-reticulated biomass flakes by carefully controlling the Maillard-like reactions, toasting, and caramelization of sugars present in the biomass or further formed by the addition of activators and self-binding precursors. These process conditions and additives control the physical properties and durability of the resulting pre-reticulated biomass flakes, and more specifically, the ultimate properties of the carbonaceous final reticulated monolithic biochar product upon carbonization in the further disclosed furnace carbonization step.

[0150] ○ The temperature range for the pre-mesh wafers in the molding oven baking step provides the best results between 80°C and 250°C. The temperature range of the pre-mesh process is highly selective because it has a sensitive effect on the formation of self-bonded biomass of the wafers. Below the lower temperature limit, the bonding effect of the fine biomass is not activated. The lower baking temperature also limits the evaporation of the aqueous solvent of the salt solution and the evaporation of the organic liquid acid or solvent, and prevents the biomass wafers from hardening, which results in loose and powdery or mushy wafers that mechanically fail and break when being manipulated or removed from the molding machine. Above the upper temperature limit, the wafers will burn, caramelize and dry out, resulting in excessive hardening and increased adhesion to the molding plate. The caramelization and poor performance in the subsequent carbonization and activation steps are caused by the collapse of the pore and scaffold structure, which greatly inhibits the activation of the final product biochar electrode.

[0151] ● It is expected that the heating and molding conditions of the low temperature press box will vary depending on the different self-binding precursors and preactivators used. The pressing conditions (pressure, temperature, and time) should be adjusted according to the preactivator used to allow the preactivator sufficient time, heat, and pressure to complete its tasks, such as self-binding, digestion, oxidation, reduction, etc.

[0152] Organic mold release agents may be applied to the mold box apparatus to prevent sticking and damage to the wafers when attempting to remove them after baking. Organic oils are preferred. Olive oil, corn oil, or rapeseed oil, or blends thereof, have been found to be suitable for minimizing, but not completely preventing, wafer sticking and damage when removing wafers from the molded plate after being removed from a low-temperature oven. Note, however, that other oils or fats may be used as they are compatible with biomass, but it is recommended that any such oils or fats applied to the molder surface have a low smoke point and burn off rapidly once the pre-reticulated biomass wafers are placed in the subsequent high-temperature carbonization furnace. These mold release oils should not adversely affect the conversion of the biomass reticulated wafers into reticulated biochar electrodes. The use of high-temperature resistant oils or lubricants, such as silicone oils, as mold release agents is discouraged because they are stable, not carbon-based, and, if used, will not react or adversely react with the biomass and will not evaporate at the early temperatures required in the furnace carbonization step. This may result in a non-conductive coating within the electrode channels and pores, which could have a detrimental effect on the electrode's performance in its final use.

[0153] High temperature carbonization

[0154] • Pre-reticulated biomass wafers are carbonized at high temperature in a furnace in the presence of inert gas to convert them into reticulated biochar electrodes.

[0155] ○The temperature of the high temperature carbonization furnace is generally between 700-1100℃.

[0156] ○ Carbonization duration at peak high temperature is generally between 30 minutes and 120 minutes. Shorter times are generally insufficient for carbonization, resulting in reduced formation of the final scaffold of the carbon structure and channels and pores. More time provides either little or no beneficial additional strength from the carbon structure scaffold, no additional channels or pores, and has the negative effect of pore and channel shrinkage, negatively impacting the electrical properties of the electrode. It should be noted that some temperature restrictions must be placed on the original pre-activation soaking of the biomass and the addition of self-binding precursors, such as those containing salts of Group I and Group II cations, such as potassium, sodium, calcium, or other metals, which become overly active and catalytic at higher temperature ranges (e.g., above 800°C). Because these ions are present in the biochar upon carbonization, the biomass / biochar material may undergo complete gasification, resulting in only a small amount of ash remaining in the high-temperature carbonization furnace where the product biochar electrode is expected to appear.

[0157] ● Additional activation can be achieved in the high temperature carbonization furnace or in a separate subsequent high temperature furnace step by introducing an activation gas such as carbon dioxide (CO2), such as steam made from water vapor (H2O), preferably evaporated alone, but also as liquid water directly added, incorporated, injected or inserted into the high temperature furnace by any safe means considering mechanical and metallurgical design. Once the carbonization temperature (800°C to 950°C) is reached, a small amount of these activation gases can be introduced into the furnace. This allows the CO2(g) or H2O(g) or a combination thereof to react with the carbon structure of the biochar electrode, thereby resulting in a reverse Boudouard reaction (for added CO2) or a steam-carbon reaction (for added H2O), respectively, to remove carbon atoms and further expand the pores of the biochar monolithic electrode material, thereby increasing the internal surface area, creating additional pores, and generating hierarchical channels throughout the 3D structure of the thick monolithic biochar wafer electrode support. This activation step should be performed at or above the carbonization temperature and should be carefully monitored and controlled to prevent excessive gasification, which could destroy or consume the reticular carbon structure and reduce it to carbon powder or completely react all the carbon therein, resulting in a residue of only ash. Gas activation can be accomplished in several steps during the high-temperature carbonization process. It can be performed during the initial biomass carbonization process, immediately after carbonization in a high-temperature carbonization furnace, without cooling between the two separate steps, or as a separate step, allowing the carbonized wafer to cool and optionally treated with an additive or cleaning step, such as adding a liquid as disclosed in the biomass pretreatment step above, such as an aqueous solution of potassium hydroxide, such as sodium hydroxide, formic acid, performic acid, acetic acid, peracetic acid (etc.), and then the (optionally wetted) biochar wafer is re-increased in temperature, as specified above for the liquid-based second activation step or CO2 / steam activation at elevated temperatures between 800-950°C in the furnace.

[0158] The flow rate and total mass of activated gas delivered is generally based on the concentration of the gases, which may be mixed with each other or with inert gases for flow conditions, and the total mass of biomass / biochar to be processed. Optimum results are achieved when the gas flow rate is between 0.001 cubic feet per hour per gram of biomass and 0.10 cubic feet per hour per gram of biomass (on a pure gas basis). When the activated gas is blended or optionally mixed with an inert gas (e.g., argon, helium) or a carrier gas (e.g., nitrogen), the flow rate and pressure must be adjusted to accommodate the actual activated gas delivered as a pure gas, adjusting the concentration or partial pressure of these mixed gases flowing into the furnace. This flow rate and total mass of activated gas delivered to the furnace should be adjusted based on the total mass of wafer material in the furnace and the degree of activation sought to be achieved.

[0159] The steps for carbonizing biomass in a high-temperature carbonization furnace are disclosed below. Pre-reticulated biomass wafers are placed on a flat tray within the furnace. The tray is typically made of metal or ceramic materials that can withstand the harsh temperatures within the furnace during carbonization, as well as the corrosive atmosphere generated by the degassing compounds and process gases added to the furnace. In the exemplary embodiment disclosed herein, Inconel alloy is used to manufacture the furnace tray. The furnace walls are also made of Inconel.

[0160] ● Place the pre-meshed biomass wafers to be carbonized directly on the tray, or preferably on a porous substrate, such as an Inconel screen below and on top of the biomass, and then place an Inconel or ceramic weight on top of the stack. This arrangement serves two purposes. The screen allows the carbonized biomass wafers to "exhale" the exhaust gases occurring from pyrolysis while carbonizing, thereby preventing or minimizing the formation of a carbonaceous film or "crust" on the outer surfaces of the biomass wafers facing the bottom tray surface and the top weigh downplate surface while the biomass is pyrolyzed and converted into a monolithic meshed biochar. Secondly, the top weight forces the carbonized wafers and the screen layer to remain flat or meshed, minimizing or eliminating any undesirable curling, saddling, or cupping of the biochar as the biomass wafers shrink in all dimensions and lose weight and size and as it hardens into a monolithic meshed biochar electrode. Note that the "flat" bottom tray and "flat" top weight described herein may be of other shapes and curved surfaces in other embodiments to match the non-planar shape of the biomass introduced in the previous heated oven pressing step, or the shape of the electrodes generated or induced directly in the high temperature carbonization furnace. These non-planar embodiments are disclosed in the '324 and '563 patents and are incorporated herein by reference.

[0161] The target temperature of the furnace is generally between 700°C and 1100°C, preferably between 730°C and 850°C, by adding heat from external heat sources such as electric heating elements, gas burners, liquid fuel burners, etc. [See, for example, the '324 and '563 patents.] These heat sources can be directly in contact with or exposed to the exterior of the furnace, or heat can be provided by piping heater exhaust or combustion products. Since inert gases such as argon, helium, or nitrogen can be used to purge the furnace internals, the carbonizing heat source can be applied directly to the furnace by heating the purge gas before it enters the furnace. Obviously, in such heating configuration embodiments, insulation should be applied to the exterior of the furnace. Finally, a combination of internal and external heating of the furnace can be performed.

[0162] Peak carbonization furnace temperature is achieved by increasing the temperature at a ramp rate from ambient temperature to the final peak carbonization temperature, for example, increasing by 8-10°C / minute toward the target temperature. Once the temperature inside the furnace reaches the target temperature, the disclosed carbonization time measurement begins. Once the furnace reaches or exceeds the target carbonization temperature, the carbonization time typically lasts from 30 to 120 minutes.

[0163] The inner cavity of the carbonization furnace is purged with an inert gas (e.g., argon, such as helium) or a neutral, non-reactive or minimally reactive gas (e.g., nitrogen). It should be noted that oxygen and "air" must be removed from the furnace cavity before the temperature in the furnace exceeds 100°C to avoid oxidation or complete destruction of the biomass once at high temperatures above 250°C. This air removal is typically achieved by adjusting the flow rate of the purge gas entering the furnace so that the total volume of the purge gas passing through the furnace is equal to or greater than at least 5 volumes of the furnace interior space within the first 5 minutes of furnace heating. Once the high purge flow rate and the required volume are achieved, the purge gas flow rate can be reduced to the desired minimum, i.e., 0 to 20 furnace volumes per hour. Once the biomass carbonization in the furnace is completed according to the time and temperature guidelines disclosed above and described in the Examples and Control Examples section below, the carbonization furnace can be cooled.

[0164] Charring oven cooling is typically accomplished by using an external air stream that flows around the outside (not inside) of the oven cavity and optionally, a cooling stream of continuous or higher flow rate purge gas for internal cooling is applied to the oven, thereby cooling the oven and the biomass wafer and stopping the charring process. This forced external and internal cooling step can be omitted and the oven can be allowed to cool by normal ambient atmospheric convection, thermal radiation and heat conduction; however, it should be clearly understood that this ambient cooling slows the cooling process and in effect increases the charring time of the oven charring step by keeping the charred reticulated biochar electrode at an elevated temperature beyond the planned and expected charring time-temperature curve. This can have unpredictable results on the properties of the biochar electrode due to the uncontrolled nature of the time-temperature cooling curve and the random lengthened charring time that would occur if the disclosed forced cooling was omitted. Once the desired charring is complete, the disclosed forced cooling acts to stop the charring process more quickly and allows more control over the resulting properties of the biochar electrode wafer exiting the oven once cooled enough to stop any further chemical conversion. In addition, the oven should not be opened to the atmosphere, ambient air or oxygen when the biochar wafer is hot as spontaneous combustion of the biochar will occur and undesirable oxidation of the carbon biochar electrode material will occur. The cooling air for external cooling of the oven can come from a common compressor or air pump or fan, preferably at room temperature (e.g., about 25°C). Optionally, near saturated steam (slightly above 100°C) can be used to externally cool the oven from the charring temperature to about 150°C, after which the above mentioned ambient air cooling or air stream can complete the oven cooling. These times and end temperatures depend on the mass of the charring oven, the oven interior configuration and the loading of biochar within the oven, generally about 90 minutes is needed, after which the oven can be allowed to fully cool to room temperature by simple exposure to ambient air, after which the cooled oven can be subsequently opened in order to remove the reticulated monolithic activated biochar electrode.

[0165] Experimental results

[0166] Experiment #1

[0167] The pre-reticulation wafer was prepared from 50% medium grind and 50% 80 pm grind dry mass ratio, 0.65 g of proprietary biomass mixture per wafer. A pre-activation solution was prepared containing 10% KOH (wt / wt) in distilled water. The mass ratio of KOH solution to dry biomass was 0.60 g KOH (aq) solution per 1.0 g of biomass, for a total of 12.0 g of biomass was treated in a low temperature press oven for preparation. The solution was added drop-wise to the dry biomass, mixed thoroughly, and allowed to sit for 15-30 minutes. To pre-reticulate the biomass into wafers, a metal template system was used, which consisted of three stainless steel plates, each 5 / 16 inch thick, with the center plate being the template with cylindrical openings. To prepare the template, an organic release agent (olive oil) was sprayed on the middle and bottom plates of the mold. The lower and middle templates were secured with five hex nuts (3 / 8 inch diameter x 16 pitch, 3 / 4 inch long) to form the mold tray. The biomass mixture (consisting of biomass, pre-activation agent, and distilled water) that was wetted with pre-activation agent and / or precursor was then evenly distributed into the cylindrical holes of the middle template. The four sides of the metal cylindrical blocks were wetted with olive oil. The oil-wetted metal cylindrical blocks were then inserted into each of the mold cylindrical slots filled with the biomass mixture, thereby uniformly compressing the biomass. These metal cylindrical blocks were designed and manufactured to fit into the press plate cylindrical openings with minimal side clearance, with a height less than the depth of the press plate cylindrical well, leaving a designed gap space below the metal blocks while residing in the press plate cylindrical well. This gap space is the space that forms the pre-reticulated biomass wafer upon full pressing as described below. After filling the press plate cylindrical holes with the biomass mixture and inserting the oil-wetted cylindrical metal blocks into the same press plate holes, the top plate was then placed on the entire assembly to uniformly press down on the cylindrical blocks and compress and pre-reticulate the biomass. The openings in the top plate allowed the hex nut heads of the bolts that secured the two lower plate assemblies together to not interfere with the press assembly. Multiple sets of cylindrical blocks were customized that all had a tight side wall clearance to the cylindrical holes of the middle piece of the template section, and these cylindrical blocks had specific heights so that when these cylindrical blocks were placed in the press cylindrical well, different thicknesses of pre-reticulated biomass wafers were obtained based on the gap below the cylindrical blocks. The height of the cylindrical blocks was typically 60-90% of the height / gap of the cylindrical hole, thereby also setting the disclosed compression ratio of the biomass from a loosely mixed state to a compressed state. The entire stacked template, including the base, shape mask (cylindrical hole) layer, and top press plate layer, was pressed in a heated hydraulic press (Carver) at 120 °C for 1 hour to form the pre-reticulated biomass wafer with an average thickness of 0.07 inches and an average mass of 0.800 grams per wafer.

[0168] After baking the pre-reticulated biomass wafers in a template system, the wafers are placed on Inconel trays for placement in a furnace where they are subjected to high-temperature carbonization between 750°C and 850°C under inert gas (N2) with a 60-minute temperature ramp time in the furnace, and an additional 60 minutes of carbonization at a peak target hold temperature to convert them into final reticulated monolithic biochar electrodes for supercapacitors, batteries, fuel cells, and other adsorptive applications. When placed in the carbonization furnace, the wafers are held between ceramic plates to avoid deformation, saddle-shaped, or cupping (which can be caused by uneven heating of the furnace or uneven moisture distribution caused by poor mixing of the biomass with the activator and precursor liquids in the previous step). The flattened, compressed biomass material thus produces a flat, cylindrical biochar product, similar in shape to a coin. In addition, before insertion into the furnace for carbonization, a layer of Inconel mesh is inserted between the biomass pre-reticulated wafer and the ceramic plates on the top and bottom of the wafer to allow for degassing of the pyrolysis byproducts of the biomass carbonization during and after this basic carbonization step. This is manifested in that tar and other organic biomass vapors do not accumulate at the interface of the biomass / biochar surface and the tray or top weight, and prevents these exhaust gases from scorching and hardening on the electrode surface, causing it to close. The carbonized biomass wafers need to breathe while being carbonized. This screen layer in the carbonization process assembly also facilitates gas entry into the carbonized biomass wafer electrodes for any additional subsequent activation during or after the basic carbonization step by using added atmosphere gases (examples: disclosed CO2 or steam). (This subsequent gas activation step of this experiment was not performed in this experimental example, but is stated here to support where and how it may appear in the method and is exemplified in subsequent examples.)

[0169] After the carbonization in the furnace is completed, cooling is started by a compressed forced air flow around the outside of the furnace, and the air flow is blown between the outside insulation heater of the furnace and the outside of the furnace metal wall. After complete cooling and extraction from the carbonization furnace, before the electrochemical capacitance test, the electrode is ultrasonically treated in distilled water and electrolyte solution to remove any loose particles and impurities. A battery tester (Vencon Model UBA5) is used to measure the capacitance of the electrode pair. The supercapacitor battery is assembled using two electrodes and a diaphragm between a titanium current collector completely sandwiched between a titanium foil with a thickness of 0.02 inches and using 6.0M KOH (aq) as an electrolyte. For a 1.0 volt operating window, the measured specific capacitance is 150 farads / gram.

[0170] Experiment 2: Brewery spent grains used as a biomass source:

[0171] Experiment #2 used brewery spent grain biomass in place of fine biomass, at the same mass ratios as the medium biomass used in Experiment #1 (above), to explore its potential as a successful component of the mesh electrode and its performance. Malted barley (2-row malt was used, but the application is not particularly limited to 2-row malted barley) was obtained from a local home brewing supply store for use in this experiment. The inventor's experimental team performed the actual selection, weighing and grinding of dry grains, as well as the brewing steps, to produce the spent grain biomass source. The 2-row malted barley was ground using a hand grinder typically used in home breweries, thus supporting the above-mentioned public statement that any method can be used for biomass grinding as long as the necessary particle size and loosening can be achieved in this way. The ground grain material was washed 3 times in clean boiling filtered and demineralized tap water to extract sugars from the barley, and the brewing process was repeated. The resulting 2-row barley was labeled "Spent Grain (2-row)". The spent grain was then dried in a vacuum oven at a temperature not exceeding 60°C to prevent caramelization or residual sugars. The dried spent grain was then ground using a laboratory Retch Model ZM-200 grinder at 18,000 RPM using a 24-tooth rotor and an 80 μm screen to obtain a biomass particle size equivalent to the "fine #5 blend" biomass. The remaining procedures for making the spent grain wafers and electrodes were similar to those outlined in Experiment 1, except that fine spent grain from two-row barley was used instead of fine biomass.

[0172] The resulting single pair of biochar electrodes was assembled as described above in Experiment #1, and the specific capacitance was measured to be 120 Farads / gram in the 1.0 volt operating window.

[0173] Experiment 3: Using different biomass source mixtures

[0174] Similar to Experiment 2, other biomass materials such as reed palm, reed, and bamboo were explored for the same reasons of source or plant species diversity. Each of these biomass materials was dried in a vacuum oven at 60°C to remove moisture and then ground to a specific particle size, specifically for self-binding purposes (fine) or scaffolding and bulk contribution purposes (medium).

[0175] The results showed that bamboo performance varied depending on the part used (stem, stalk, or leaf). While bamboo stems exhibited high fiber integrity after grinding and could serve well as a "reinforcing bar" scaffold for electrodes, the high silica content of bamboo leaves prevented further exploration as a potential candidate through the examples utilized. These other plant species were processed using the same mixing and carbonization process as in Experiments #1 and #2 above.

[0176] The supercapacitor cell was assembled using two electrodes made from bamboo stalks, a separator (CelGard 3401) sandwiched between 0.02-inch-thick titanium foil, and 6.0 M KOH (aqueous solution) as the electrolyte. For a 1.0-volt operating window, the measured specific capacitance was 82 farads per gram.

[0177] The supercapacitor cell was assembled using two electrodes made from palm bamboo, a separator (CelGard 3401) sandwiched between 0.02-inch-thick titanium foil, and 6.0 M KOH (aq) as the electrolyte. The measured specific capacitance was 67 farads per gram for a 1.0-volt operating window.

[0178] Electrodes made from bamboo leaves and bamboo stems cannot be used because they are brittle and lack self-bonding after carbonization in a furnace.

[0179] Experiment 4: Results of post-carbonization activation with and without CO2

[0180] In experiment #4, similar to experiment #1, the nitrogen flow entering the furnace during the high temperature carbonization process was replaced by a carbon dioxide flow (0.3 cubic feet per hour). This purge gas replacement was performed only during the high temperature carbonization stage to evaluate the effect of gas activation after the basic 60-minute high temperature carbonization step was completed. This is believed to be beneficial for the additional activation of the reticulated carbonaceous electrode. It is well known that when CO2 is introduced in the presence of carbonaceous material, CO2 will react with the carbonaceous material to form CO (carbon monoxide) through a reverse Boudouard reaction, thereby "etching" the carbonaceous structure on the surface and inside the monolithic biochar electrode and creating more pores and channels. After the high temperature CO2 carbonization treatment, the resulting wafers showed good higher capacitance. It was observed that the surface of the CO2 activated monolithic electrodes was rougher than those without CO2 activation. This is a result of the intrusion and etching effect of CO2, as the gas distinguishes reactive and non-reactive sites based on the morphology of the biochar used for CO conversion.

[0181] Supercapacitor cells were assembled using two electrodes made from 50% medium-ground biomass and 50% 80 μm fine-ground biomass (but wetted with formic acid when preparing pre-reticulated biomass wafers for low-temperature baking). These formic acid-treated wafers were carbonized in a high-temperature furnace using an alternative CO2-activated purge gas and assembled with a separator (CelGard 3401), 0.02-inch thick titanium foil, and 6.0 M KOH (aq) as an electrolyte. For a 1.0 volt operating window, the measured specific capacitance was 208 farads / gram.

[0182] A second batch, carbonized in a furnace with all other conditions being the same but without the addition of post-carbonization CO2, allowed the assembly of a supercapacitor cell similarly using two electrodes made from 50% medium-ground biomass and 50% fine 80 μm ground biomass (but wetted with formic acid) carbonized as above, and assembled with a separator (CelGard 3401), a 0.02-inch thick titanium foil, and 6.0 M KOH (aq) as an electrolyte. For a 1.0 volt operating window, a specific capacitance of 92 farads / gram was measured.

[0183] Experiment 5: Use of the prepared biochar electrodes in fuel cells

[0184] Experiment #5 used a pair of separate monolithic biochar electrodes to create a basic cold fuel cell. To demonstrate that embodiments of these end-product electrodes produced by the disclosed methods could generate direct current (DC), a simple biofuel cell was assembled. Common garden soil (topsoil) was placed in a clear, 1-pint glass container. The biochar electrodes, produced by the method of Experiment #1 disclosed above, were each connected to a separate wire and inserted into the garden soil, with the wire extending out without contacting the soil. A common gel separator (agar or equivalent) was poured between the electrodes, dividing the soil into two "chambers." The separator gel is insulating to electrical current, but the micropores allow for diffusion of gases and ions. After allowing the microorganisms to activate for several hours to produce methane, hydrogen, and oxygen, a potential of 0.5 volts was observed across the two wires extending from the two submerged subject electrodes. Despite its simplicity, Experiment #5 fully supports the claim that the electrodes produced by the disclosed methods function in a fuel cell. Note that the disclosed method for fully fabricating these monolithic biochar electrodes utilizes a high temperature furnace, and the resulting electrodes can withstand such high temperatures when used as electrodes for typical high temperature PEM fuel cells and other fuel cell embodiments beyond the simple experiment #5 described herein.

[0185] Experiment #6: Using biochar electrodes in a water electrolysis based gas generator to produce hydrogen and / or produce oxygen.

[0186] Experiment #6 demonstrated that the disclosed reticulated biochar monolithic electrodes could be used in a water electrolysis gas generator. In this particular experiment, the electrolytic medium was distilled water containing sufficient potassium hydroxide as a solute to a concentration of approximately 6 molar (approximately 30% by weight KOH in distilled water). The addition of this electrolyte typically follows a method known as "alkaline electrolysis." The disclosed monolithic highly porous biochar electrodes, manufactured according to the methods disclosed herein and more specifically according to the recipe used in Experiment #1 above, were each secured along their edges to a conductive clip and wire and then immersed in a 6 molar aqueous KOH electrolyte solution. Care was taken to ensure that only the electrode monolithic body was immersed in and in contact with the electrolyte solution, and that the attached conductive wire, conductive clip, or fastener did not contact the electrolyte solution liquid. The positive terminal of the power supply was connected to one lead of one monolithic electrode, and the negative terminal of the power supply was connected to the other lead of the other monolithic electrode. Since both electrodes had the same recipe and manufacturing method, the polarity of the power supply leads was arbitrarily assigned to either monolithic biochar electrode. Once the electrodes were immersed in the electrolyte and all wires and fasteners were connected, a power source was turned on, applying a voltage to the electrode pair. A voltage greater than 1.23 volts, and further greater than 1.7 volts, and particularly 5 volts, was applied to the electrodes via wires connected to a DC power supply set to a 5 volt potential. After a brief period of approximately 15 seconds of immersion of the highly porous monolithic biochar electrodes in a 6 molar KOH aqueous solution, both electrodes began to produce a large number of bubbles on the wetted surface of the monolithic electrodes. Once gas generation began, a current of 0.75 amps or 1.2 amps per square inch was observed over the total cross-sectional area of ​​each wetted portion of the 0.625 square inch electrode. Gas samples confirmed the production of hydrogen at the negative electrode and oxygen at the positive electrode.

[0187] Control Experimental Examples: The following are two examples of control experiments where specific details of the disclosed methods were intentionally not followed and the end results were either poor or the example electrodes failed completely.

[0188] Control experiment 1: Non-mixed two-row hop leads to fragile electrodes

[0189] Experiment #1 was repeated as a control, using only 2-row barley as a fine grind, produced using a Retsch ZM-200 at 18,000 RPM, a 24-tooth rotor, and an 80 μm screen. 2-row barley performed poorly after pressing or carbonization. The wafer surface was very rough, making it unsuitable for use as an electrode. This resulted in membrane puncture, uneven contact with the metal foil current collector, mechanical fragility, and excessive expulsion of carbonized byproducts during sonication.

[0190] Control experiment 2: The CO2 gas activation flow rate was too large, the chip broke, and the self-binding effect of the fine biomass was lost.

[0191] In an experiment similar to Experiment 4, a higher CO2 gas flow rate (0.5 cubic feet per hour) was used. After carbonization, it was observed that the original reticulated carbon flakes expected to be found in the furnace had actually been reduced to carbon powder and small clumps of carbon powder. This is most likely due to structural destruction of the carbonaceous material caused by excessive gasification. Therefore, the mass ratio of CO2 to carbonaceous material should be carefully selected to prevent excessive gasification, which would result in the conversion of most or all of the carbonaceous material to CO (carbon monoxide), ultimately reducing the reticulated flakes to an unusable powder.

[0192] Although the system and method of the present invention have been described with reference to various exemplary embodiments and implementations, it will be understood by those skilled in the art that the present invention is not limited to or restricted to these exemplary embodiments / implementations. Rather, the disclosed system / method may be changed, modified, improved, and / or enhanced without departing from the spirit or scope of the present disclosure.

Claims

1. A method for making an electrode for use in a supercapacitor, pseudocapacitor, or battery, comprising: a. forming one or more biochar electrodes by: (i) formulating a biomass mixture with biomass having different particle sizes, wherein the biomass mixture is derived from a mixture of biomass having grind sizes including a coarse grind, a medium grind, and a fine grind, wherein the biomass grind size measured in the longest dimension is selected from the group consisting of the following grind sizes: 1 mm to 2 mm, 1 mm to 500 μm, 500 μm to 200 μm, 200 μm to 120 μm, 120 μm to 80 μm, 80 μm to 25 μm, and 25 μm to 20 μm; (ii) wetting the biomass mixture with an aqueous precursor solution that is neither a binder nor an adhesive, the aqueous precursor solution being used to soften the surfaces of lignin, hemicellulose, and cellulose associated with the biomass mixture, the wetted biomass mixture having a viscosity of 0.5 g / cm 3 Up to 4g / cm 3 (iii) casting or molding the biomass mixture in an oven-pressed platen mold in the presence of a self-binding precursor compound and without a binder material to form pre-reticulated biomass wafers, wherein a portion of the biomass mixture recombines or rebonds to another portion of the biomass mixture during the casting or molding based on the presence of the self-binding precursor compound, and (iv) carbonizing the pre-reticulated biomass wafers in a furnace to form a reticulated biochar electrode; b. combining the reticulated biochar electrode with one or more charge collectors, a separator, and one or more electrolytes.

2. The method according to claim 1, wherein The self-binding precursor compound includes an acid, a basic salt, a neutral salt, or a solvent.

3. The method according to claim 2, wherein: The self-binding precursor compound comprises an acid selected from the group consisting of formic acid, performic acid, acetic acid, peracetic acid, boric acid or nitric acid or any mixture thereof, or hydrogen peroxide.

4. The method according to claim 2, wherein: The self-binding precursor compound comprises a basic salt selected from the group consisting of potassium hydroxide, sodium hydroxide and other metal salts or any mixture thereof.

5. The method according to claim 2, wherein: The self-binding precursor compound includes a solvent, which is water or an organic solvent selected from the group consisting of methanol, ethanol, toluene, dimethylformamide or hexane, or any mixture thereof.

6. The method according to claim 2, wherein: The self-binding precursor compound is added to the biomass mixture at a level between 5 wt% and 91 wt% relative to the mass of the biomass mixture.

7. The method according to claim 1, wherein The casting or molding of the biomass mixture is carried out at elevated temperature and pressure according to the following conditions: a. The temperature range is 80°C to 250°C; and b. Pressure range is 1000psi to 60,000psi.

8. The method of claim 1 further comprising adding a mold release compound to coat a platen mold associated with oven pressing.

9. The method according to claim 8, wherein The release compound is an organic compound that is compatible with the biomass mixture.

10. The method according to claim 9, wherein: The release compound is selected from the group consisting of any vegetable fat or any animal fat, and wherein the release compound is applied by wetting and spreading, or by spray coating.

11. The method according to claim 7, wherein: The biomass mixture is oven pressed for a period of time ranging from 1 to 180 minutes.

12. The method according to claim 1, wherein High temperature carbonization is performed in a purged, high temperature furnace to convert the pre-reticulated biomass wafers into the reticulated biochar electrodes.

13. The method according to claim 12, wherein: The carbonization temperature ranges from 700°C to 1100°C and is achieved at a heating rate of 5 to 20°C / min.

14. The method according to claim 1, wherein A flat or curved holder made of ceramic or metal holds the pre-reticulated biomass wafers during carbonization.

15. The method according to claim 14, wherein A screen is inserted between the interface between the flat or curved holder and the pre-meshed biomass wafer to allow degassing from the pre-meshed biomass wafer while in the carbonization furnace, thereby preventing tar, sugars, oligomers or other organic residues from accumulating in the carbonization pores of the reticulated biochar electrode.

16. The method according to claim 15, wherein Also included is inputting an activation gas into the carbonization furnace, and wherein the mesh allows the activation gas to penetrate the entire surface of the pre-meshed biomass wafer, the meshed monolithic biochar electrode, or both.

17. The method according to claim 15, wherein: The screen is made of a high temperature resistant material, which is selected from the group consisting of Inconel screen, corrugated or perforated Inconel plate or membrane, stainless steel screen, corrugated or perforated stainless steel plate or membrane, titanium screen, corrugated or perforated titanium plate or membrane, other high temperature resistant precious metals or semi-precious metals or their alloys, or ceramic materials or woven or non-woven ceramic fiber cloth or porous filler.

18. The method according to claim 1, wherein An inert purge gas is introduced into the carbonizer at a flow rate of 0.01 to 0.2 cubic feet per hour per gram of biomass while the carbonizer is at an elevated carbonization temperature.

19. The method according to claim 1, wherein An activation gas is introduced into the carbonization furnace during or after carbonization, or into a separate furnace to further activate the reticulated biochar electrode.

20. The method according to claim 19, wherein The activation gas is superheated steam or carbon dioxide and is introduced into the carbonization furnace at a space velocity of 0.001 to 0.1 cubic feet per hour per gram of biomass mixture.

21. The method according to claim 1, wherein The reticulated biochar electrodes extracted from the carbonization furnace were ultrasonically treated in a liquid solvent to remove loose particles.

22. The method according to claim 21, wherein The liquid solvent is distilled water, deionized water or an electrolyte aqueous solution, or any soluble or flushable detergent, cleaning agent, organic solvent or purifier.

23. The method according to claim 21, wherein The reticulated biochar electrode after ultrasonic treatment is rinsed with deionized water, distilled water, electrolyte solution or volatile organic solvent, and dried for use in aqueous or nonaqueous electrical applications or adsorptive applications.

24. The method according to claim 21, wherein The ultrasonically treated reticulated biochar electrode is paired with at least one non-aqueous ionic salt compound in at least one organic solvent or ionic liquid.

25. The method according to claim 21, wherein The reticulated biochar electrodes after ultrasonic treatment are rinsed and dried for use in non-aqueous electrical applications selected from the group consisting of supercapacitor electrodes, pseudocapacitors, and batteries, each electrode being paired with a non-aqueous ionic liquid.

26. The method according to claim 21, wherein The reticulated biochar electrode after ultrasonic treatment is rinsed and dried for use in a non-liquid based electrical application selected from the group consisting of supercapacitor electrodes, pseudocapacitors and batteries, and wherein the electrolyte is a solvated solid electrolyte inserted into the electrode channels and pores by soaking or vacuum impregnation and re-pressurization while immersed in a solvated solid electrolyte transport solution, followed by drying and repeating to achieve a desired electrode channel and pore capacity utilization for solid electrolyte loading.

27. The method according to claim 26, wherein The impregnated electrolyte or electrolyte precursor is a polymer to which ionically charged radicals are attached.

28. The method according to claim 27, wherein The polymers serve as solvents or copolymers for the additional addition of ionic liquids, leading to chemical and physical phase transitions in the polymer-ionic liquid mixture, converting the electrolyte into a solid-like self-assembled state and structural organization for enhanced conductivity and charge storage.

29. The method according to claim 1, wherein The reticulated biochar electrode is used as a supercapacitor electrode, a pseudocapacitor or an electrode in a battery.

30. The method of claim 1, further comprising at least one post-processing operation to modify the mesh shape of the reticulated biochar electrode.

31. The method of claim 1 further comprising the assembly of a supercapacitor, pseudocapacitor, or battery comprising securing the reticulated biochar electrodes relative to a metal charge collecting foil or plate using a highly conductive carbon glue.

32. The method of claim 1 further comprising assembly of a supercapacitor, pseudocapacitor, or battery comprising securing the reticulated biochar electrodes relative to a metal charge collecting foil or plate using a highly conductive metal epoxy.

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