Systems and methods for storing electrical energy

Abstract

The present disclosure provides capacitors for storing electrical energy. The capacitors can at least partially include bast fibers, bast powder, stalk core fibers, stalk core powder, or derivatives thereof. In some cases, the dielectric of the capacitor can be formed from bast fibers, bast powder, stalk core fibers, stalk core powder, or derivatives thereof. In other cases, one or both electrodes of the capacitor can be formed from bast fibers, bast powder, stalk core fibers, stalk core powder, or derivatives thereof. The resulting capacitors can be configured to have various power densities and various energy densities within a specified operating temperature range and within a minimum number of charge / discharge cycles.

Description

[0001] This application is a divisional application of a Chinese patent application with an application date of March 28, 2018, an application number of 201880035688.3, and an invention title of "Systems and Methods for Storing Electrical Energy" (the corresponding PCT application has an application date of March 28, 2018 and an application number of PCT / US2018 / 024939).

[0002] Cross-reference

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 478,553, filed on March 29, 2017, and U.S. Provisional Patent Application No. 62 / 540,147, filed on August 2, 2017, each of which is hereby incorporated by reference in its entirety. BACKGROUND OF THE INVENTION

[0004] Capacitors are energy storage systems that can include higher power densities and can thus release energy over shorter time periods compared to some alternative energy storage systems (e.g., batteries). Supercapacitors can be configured to store several orders of magnitude more charge (and thus electrical energy) than ordinary capacitors while still including a relatively high power density. In some cases, the material properties of capacitors and supercapacitors, such as the materials of the electrodes and dielectrics of the capacitors and supercapacitors, can affect the performance of the capacitors. For example, in some cases, electrodes with a larger surface area may perform better than electrodes with a smaller surface area. Also, for example, in some cases, dielectrics with a relatively high relative dielectric constant may perform better than dielectrics with a relatively low relative dielectric constant. SUMMARY OF THE INVENTION

[0005] The present invention provides capacitors for storing electrical energy, where the capacitors at least partially include bast and / or hurd or derivatives thereof. For example, the capacitors can include bast fibers, bast powders, hurd fibers, hurd powders, or derivatives thereof. In some embodiments, the dielectric of the capacitor can be formed from bast fibers, bast powders, hurd fibers, hurd powders, and / or derivatives thereof. In some embodiments, one or both electrodes of the capacitor can be formed from bast fibers, bast powders, hurd fibers, hurd powders, and / or derivatives thereof. The resulting capacitors can be configured to have various power densities and various energy densities and can withstand various minimum numbers of charge / discharge cycles within a specified operating temperature range.

[0006] In one aspect, a capacitor for storing electrical energy is provided, wherein the dielectric of the capacitor is formed of bast or shive material or derivatives thereof. The capacitor may include a first electrode formed of a material capable of conducting electrons to or from an electrical load; a dielectric adjacent to the first electrode, wherein the dielectric is formed of bast fibers, bast powder, or derivatives thereof; and a second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from the electrical load, and wherein the second electrode is electrically isolated from the first electrode.

[0007] Electrical energy can be stored in the capacitor including a dielectric formed of bast or shive material or derivatives thereof by activating the capacitor, electrically connecting the capacitor to the electrical load, and charging or discharging the capacitor via the electrical load.

[0008] In some embodiments, at a temperature of 60°C - 100°C, the capacitor can have a power density of at least about 55 kilowatts (kW) / kilogram (kg) effective mass, 75 kW / kg effective mass, or 100 kW / kg effective mass in at least about 250 charge / discharge cycles via the electrical load.

[0009] In some embodiments, at a temperature of 60°C - 100°C, the capacitor can have a power density of at least about 55 kW / kg effective mass in at least about 250 charge / discharge cycles, 500 charge / discharge cycles, 1000 charge / discharge cycles, or 2000 charge / discharge cycles via the electrical load.

[0010] In some embodiments, at a temperature of 60°C - 100°C, the capacitor can have an energy density of at least about 40 watt - hours (Wh) / kg effective mass or 60 Wh / kg effective mass in at least about 250 charge / discharge cycles via the electrical load.

[0011] In some embodiments, the electrical load to which the electrodes of the capacitor conduct electrons to or from can be a power grid. Alternatively, the electrical load can include the circuitry of a vehicle, an aircraft, a train, or a ship.

[0012] In some embodiments, the dielectric of the capacitor can be formed of bast materials such as hemp bast or kenaf bast. The bast material can be in the form of bast fibers, bast powder, or derivatives thereof. In some embodiments, the dielectric can include shive (or fiber bundle) materials such as hemp shive or kenaf shive. The shive material can be in the form of shive fibers or shive powder.

[0013] In some embodiments, the capacitor can have a mass of at most about 2 kg or 5 kg.

[0014] In another aspect, a capacitor for storing electrical energy is provided, wherein a first electrode, a second electrode, or both the first electrode and the second electrode of the capacitor are formed of bast or rod core material or a derivative thereof. The capacitor can include a first electrode formed of a material capable of conducting electrons to or from an electrical load; a dielectric adjacent to the first electrode, wherein the dielectric is formed of a material having a lower conductivity than the material of the first electrode; and a second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from an electrical load, and wherein the second electrode is electrically isolated from the first electrode, and wherein the first electrode, the second electrode, or both the first electrode and the second electrode are formed of bast or rod core material or a derivative thereof.

[0015] Electrical energy can be stored in the capacitor including a first and / or second electrode formed of bast or rod core material or a derivative thereof by activating the capacitor, electrically connecting the capacitor to the electrical load, and charging or discharging the capacitor via the electrical load.

[0016] In some embodiments, at a temperature of 60 °C - 100 °C, the capacitor can have a power density of at least about 55 kilowatts (kW) / kilogram (kg), 75 kW / kg, or 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load.

[0017] In some embodiments, at a temperature of 60 °C - 100 °C, the capacitor can have a power density of at least about 55 kW / kg of effective mass in at least about 250, 500, 1000, or 2000 charge / discharge cycles via the electrical load.

[0018] In some embodiments, at a temperature of 60 °C - 100 °C, the capacitor can have an energy density of at least about 40 watt-hours per kilogram (Wh / kg) or 60 Wh / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load.

[0019] In some embodiments, the electrical load to which the electrodes of the capacitor conduct electrons to or from can be a power grid. Alternatively, the electrical load can include the circuitry of a vehicle, an aircraft, a train, or a ship.

[0020] In some embodiments, the first and / or second electrodes of the capacitor can be formed from bast materials such as hemp bast or kenaf bast. The bast materials can be in the form of bast fibers, bast powders, or derivatives thereof. In some embodiments, the first and / or second electrodes can include a shiv (or fiber bundle) material such as hemp shiv or kenaf shiv. The shiv material can be in the form of shiv fibers or shiv powders.

[0021] In some embodiments, the capacitor can have a mass of at most about 2 kg or 5 kg.

[0022] In another aspect, a method of manufacturing a capacitor is provided, comprising: (a) obtaining bast and / or shiv materials derived from a plant; (b) processing the bast and / or shiv materials into a processed material, the processed material being in the form of fibers or granules; (c) using the processed material to generate a first electrode, a second electrode, and / or a dielectric; and (d) assembling the first electrode, the second electrode, and the dielectric to produce the capacitor, the capacitor comprising (i) the first electrode, (ii) the dielectric adjacent to the first electrode, and (iii) the second electrode adjacent to the dielectric, wherein the second electrode is electrically isolated from the first electrode, and wherein the capacitor has a power density of at least about 55 kilowatts (kW) per kilogram (kg) of effective mass at a temperature of 60 °C to 100 °C over at least about 250 charge / discharge cycles via the electrical load.

[0023] In some embodiments, the plant is cannabis.

[0024] In some embodiments, the processing includes pulverizing the bast and / or shiv materials to form granules comprising the bast and / or shiv materials.

[0025] In some embodiments, the bast and / or shiv materials include bast and / or shiv fibers. In some embodiments, the bast and / or shiv materials are bast materials. In some embodiments, the bast and / or shiv materials are shiv materials.

[0026] In some embodiments, the method further includes weaving the capacitor into a fabric.

[0027] In some embodiments, the capacitor has a power density of at least about 75 kW / kg of effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C. In some embodiments, the capacitor has a power density of at least about 100 kW / kg of effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg of effective mass over at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg of effective mass over at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg of effective mass over at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0028] In some embodiments, the electrical load is the power grid. In some embodiments, the electrical load includes the circuitry of a vehicle.

[0029] In some embodiments, the capacitor has a mass of at most about 5 kg. In some embodiments, the capacitor has a mass of at most about 2 kg.

[0030] In some embodiments, the capacitor has an energy density of at least about 40 Wh / kg of effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C. In some embodiments, the capacitor has an energy density of at least about 60 Wh / kg of effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0031] Based on the following detailed description, other aspects and advantages of the present disclosure will become readily apparent to those skilled in the art. Only illustrative embodiments of the present disclosure are shown and described in the following detailed description. It should be recognized that the present disclosure is capable of other and different embodiments, and that several details can be modified in various obvious aspects, all without departing from the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0032] Incorporated by reference

[0033] All publications, patents, and patent applications mentioned in this specification are hereby incorporated by reference herein to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. If the publications and patents or patent applications incorporated by reference conflict with the disclosure contained in this specification, then this specification will supersede and / or take precedence over any such conflicting material. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings (also referred to herein as "figures"), in which:

[0035] Figure 1 A schematic diagram of a capacitor or supercapacitor is shown.

[0036] Figure 2 A method of using a phloem fiber or phloem powder capacitor is shown.

[0037] Figure 3 A schematic diagram of a capacitor in electrical communication with an electrical load is shown. DETAILED DESCRIPTION

[0038] Although various embodiments of the invention have been shown and described herein, it will be readily apparent to those skilled in the art that such embodiments are provided by way of example only. Many variations, changes, and substitutions may occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed.

[0039] As used herein, the term "phloem fiber" generally refers to natural (e.g., plant) fibers and / or other materials collected from the phloem ("inner bark", sometimes referred to as "skin") or bast surrounding the stems of certain dicotyledonous plants. Such plants can include, for example, cannabis plants. Phloem fibers can be obtained from herbaceous plants cultivated in agriculture, such as, for example, flax, hemp, jute, sisal, kenaf, or ramie. Phloem fibers can be obtained from wild plants such as stinging nettle, and trees such as lime, linden, wisteria, or mulberry. Phloem fibers can be obtained from natural materials by, for example, retting or otherwise extracting from the inner xylem or epidermis (e.g., bark surface) of the plant. For example, the retting (e.g., water retting, dew retting, chemical retting, etc.) process can remove the sticky (pectinous) substances from the phloem fibers to separate them. In some cases, phloem fibers can be obtained via decortication or manually or mechanically peeling the bark from the plant. In some cases, after extracting the phloem fibers (e.g., via peeling), the stalks, stems, or cores of the plant, such as shives or fiber bundles, can be obtained.

[0040] As used herein, the term "phloem powder" generally refers to powdered phloem fibers and / or powder of the phloem or bast surrounding the stems of certain dicotyledonous plants. In some cases, the phloem powder may contain particles in the nano- or micro-meter range. The particles may be cellulose particles derived from the phloem or phloem fibers, such as microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC). In some cases, MCC and NCC can be separated and / or derived from the phloem or phloem fibers via acid hydrolysis (e.g., hydrochloric acid hydrolysis). The phloem powder may include nanoparticles and / or microparticles. The phloem powder may be hemp phloem powder, kenaf phloem powder, sisal phloem powder, and / or jute phloem powder.

[0041] As used herein, the term "core fiber" or "fascicle fiber" generally refers to natural (e.g., plant) fibers and / or other materials collected from the stalks, stems, or cores of certain dicotyledonous plants. Such plants may include, for example, hemp plants. Core fibers can be obtained from herbaceous plants cultivated in agriculture, such as, for example, flax, hemp, jute, sisal, kenaf, or ramie. Core fibers can be obtained from wild plants such as stinging nettle, and trees such as lime tree, linden, wisteria, or mulberry. Core fibers can be obtained from natural materials by, for example, impregnating or otherwise extracting the phloem from the inner xylem or epidermis (e.g., bark surface) of the plant and harvesting the inner stalks, stems, or cores of the plant. In certain cases, core fibers can be obtained via retting or manually or mechanically peeling the phloem from the plant. In some cases, after extracting the phloem fibers (e.g., via peeling), the stalks, stems, or cores of the plant, such as the core or fascicle, can be obtained.

[0042] As used herein, the term "core powder" generally refers to powdered core fibers and / or powder of the stalks, stems, or cores of certain dicotyledonous plants. In some cases, the core powder may contain particles in the nano- or micro-meter range. The particles may be cellulose particles derived from the core or core fibers. The core powder may contain nanoparticles and / or microparticles.

[0043] Capacitors are a type of energy storage system that can include a higher power density and, thus, can release energy in a shorter period of time compared to some alternative energy storage systems (e.g., batteries). Supercapacitors, also known as electric double layer capacitors, electrochemical capacitors, or ultracapacitors, can be configured to store several orders of magnitude more charge (and thus electrical energy) than a normal capacitor while still including a high power density. Capacitors have a wide range of uses and can be configured to power electrical applications that require short, powerful energy bursts (e.g., starting an engine, rapid acceleration, stabilizing a signal, etc.).

[0044] A capacitor can include two electrodes isolated from each other by an isolating material. The isolating material can be a dielectric, or in the case of a supercapacitor, can be a separator soaked in an electrolyte. Depending on the respective materials selected for the various components of the capacitor such as the electrode material and the dielectric material, the performance of the capacitor and / or supercapacitor can be significantly enhanced or weakened.

[0045] Capacitors are provided that at least partially include natural derivatives. In some cases, the natural derivative can be phloem fiber, phloem powder, or a derivative thereof. In some cases, the natural derivative can include the stalk, stem, and / or core of a herbaceous plant or plant (e.g., flax, hemp, jute, sisal, kenaf, or ramie) or a derivative of the plant. For example, the derivative can include the shive core, shive core fiber, shive core powder, fiber bundle, fiber bundle fiber, or fiber bundle powder from hemp or flax. For example, the dielectric of the capacitor can be formed from phloem fiber, phloem powder, hemp shive core, or a derivative thereof. In another example, one or both electrodes of the capacitor can be formed from phloem fiber, phloem powder, hemp shive core, or a derivative thereof. Such capacitors can be configured to have various power densities and various energy densities within a specified operating temperature range. The capacitors can be capable of withstanding repeated charge / discharge cycles within the specified operating temperature range. The capacitors of the present disclosure can be supercapacitors.

[0046] The capacitors of the present disclosure can be capable of having a substantially high energy density (e.g., at least about 40, 50, or 60 Wh / kg) and a substantially high power density (e.g., at least about 20, 40, or 60 kW / kg). These capacitors can have various uses, such as continuously or intermittently supplying energy in buildings, vehicles (e.g., automobiles, trucks, trains, jets), or electronic devices. The capacitors can be transportable.

[0047] Reference will now be made to the accompanying drawings. It should be understood that the drawings and the features therein need not be drawn to scale.

[0048] Figure 1 A schematic diagram of a capacitor is shown. Such a capacitor can be a supercapacitor. The capacitor can store electrical energy by allowing an electric potential to accumulate between two conductive electrodes and at least one non-conductive dielectric therebetween. The illustrated capacitor includes a first electrode 104, a dielectric 106, and a second electrode 108. The dielectric 106 can include an insulating material. The dielectric 106 can include a material having a lower conductivity than either of the two electrodes. The two electrodes 104, 108 can each be capable of conducting electrons.

[0049] Although a single dielectric 106 is shown, the capacitor may include multiple dielectrics, such as at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50 or more dielectrics. The dielectrics may be disposed adjacent to each other as separate layers. The dielectrics may have a uniform distribution or may have a non-uniform distribution. For example, the dielectrics may have a substantially flat boundary or a curved boundary. The dielectrics may include the same material or different materials.

[0050] The first electrode 104 may include a first conductive material that is in electrical communication with the circuit 114 via the first terminal 115. The first terminal 115 may be a conductive component (e.g., a metal plate) separate from the first conductive material 104, or may be a connection point from the first electrode 104 to the circuit 114 and / or from the circuit 114 to the first electrode 104. The second electrode 108 may include a second conductive material that is in electrical communication with the common circuit 114 via the second terminal 116. The second terminal 116 may be a conductive component separate from the second conductive material 108, or may be a connection point from the second conductive material 108 to the circuit 114 and / or from the circuit 114 to the second conductive material 108.

[0051] In some cases, each electrode 104, 108 may include one or more adjacent layers of conductive material. In some cases, the dielectric 106 may include one or more adjacent layers of insulating material (e.g., glass, air, ceramic, etc.). The first electrode 104 and the second electrode 108 may include the same material or different materials.

[0052] The capacitance of the capacitor may depend on various factors, such as the distance between the two electrodes 104, 108, the surface area of each conductive electrode, and the dielectric constant of the dielectric, etc. For example, the capacitance may increase as the distance between the two electrodes decreases and / or as the surface area of each conductive electrode increases.

[0053] The capacitor can be charged or discharged by applying an electrical load 112 to the capacitor. For example, when a voltage is applied to the capacitor via another energy storage or power supply system (e.g., a power terminal, a battery, etc.), the capacitor can be charged. The flow of current can be interrupted by the non-conductive dielectric, and as a result, opposite charges will accumulate on the two electrodes of the capacitor. An electric potential can be generated and then stored at the dielectric between the two electrodes. In another example, the capacitor can be discharged by electrically connecting the power-consuming electrical load 112 to the capacitor. The electric potential on the electrodes can be discharged via the electrical load 112.

[0054] A supercapacitor, also known as an electric double layer capacitor, an electrochemical capacitor, or an ultracapacitor, can be configured to store an amount of electric charge (and thus electrical energy) that is several orders of magnitude greater than that stored by a normal capacitor. The capacitors of the present disclosure can store charge in an amount that is at least about 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 1000, or 10000 times greater than a typical capacitor. A supercapacitor stores electrical energy by allowing an electric potential to build up between two conductive electrodes 104, 108 at a dielectric 106 or equivalent dielectric, where each of the two conductive electrodes 104, 108 is isolated from the other by the dielectric 106 therebetween.

[0055] The dielectric 106 can include an electrolyte and / or a separator. For example, the two electrodes 104, 108 and the separator can be immersed in an electrolyte. The first electrode 104 and the second electrode 108 can be ionically connected to each other such that when the supercapacitor is charged, opposite charges can be formed on either side of the dielectric separator between the dielectric separator and each electrode via the movement of ions through the electrolyte. Unlike a battery, the electrodes do not chemically react with the electrolyte. Thus, two pairs of opposite charge layers can store an electric potential.

[0056] The two electrodes can each be capable of conducting electrons. The first electrode 104 of the supercapacitor can include a first conductive material that is electrically connected to a circuit 114 via a first terminal 115. The first terminal 115 can be a conductive component separate from the first conductive material 104, or can be a connection point from the first electrode 104 to the circuit 114 and / or from the circuit 114 to the first electrode 104. For example, the first conductive material can be formed of a porous conductive material (e.g., activated carbon, graphene, carbon nanotubes, carbon black, etc.) that is connected to the circuit 114 via the first terminal 115. The porous conductive material can advantageously increase the actual surface area of the electrode to store charge (e.g., ions), thereby increasing the capacitance of the capacitor (e.g., supercapacitor). Similarly, the second electrode 108 of the supercapacitor can include a second conductive material that is electrically connected to a common circuit 114 via a second terminal 116. The second terminal 116 can be a conductive component separate from the second conductive material, or can be a connection point from the second electrode 108 to the circuit 114 and / or from the circuit 114 to the second electrode 108. For example, the second conductive material can also be formed of a porous conductive material that is connected to the circuit 114 via the second terminal 116.

[0057] Different materials can be selected to form the electrodes and / or dielectrics of a capacitor to change the performance of the capacitor, such as power density and energy density. In some cases, the desired performance must be balanced against other considerations, such as the operable temperature range, thermal stability (e.g., flammability), structural stability, durability, toxicity, environmental impact, size limitations (e.g., dimensions, weight, etc.), manufacturing economics, and / or combinations thereof.

[0058] In some cases, pairing different materials within a capacitor, such as combining a first electrolyte composition (e.g., a first salt and a first solvent, etc.) with an electrode made of a second material (e.g., activated carbon), can produce different results. For example, a larger electrode surface area can generally increase capacitance. However, when the electrode includes a porous structure, the mobility of ions (in the electrolyte) through or between the porous structure of the electrode can affect the effectiveness of the larger available surface area. For example, the ions in a particular electrolyte composition may be too small or too large to effectively interface with the surface of the porous structure.

[0059] Compared to other alternatives, the manufacture of materials that include a relatively optimal structure for use as capacitor electrodes, such as graphene (e.g., activated graphene, curved graphene, laser scribed graphene, ultrathin planar graphene, spongy graphene, etc.) or other carbon micro- or nano-materials that include a large and flat adsorption surface and high in-plane conductivity, may be more expensive. For example, relatively costly methods such as exfoliation (e.g., the modified Hummers method), chemical vapor deposition, or microwave synthesis can be used to synthesize graphene-like materials. In contrast, carbon derived from petroleum or biomass waste can be synthesized by pyrolysis or hydrothermal methods.

[0060] In some cases, biomass such as bast fiber material, bast powder material, or hemp shive material (e.g., fiber or powder) can be used as a precursor for manufacturing components of the capacitors of the present disclosure, such as graphene-like carbon nanosheet structures (e.g., carbon sheets having dimensions from 1 nanometer to up to 1000 nanometers or 500 nanometers) using conventional processes such as hydrothermal synthesis. For example, such precursors can be formed in the form of sheets, tubes, or rolls. Bast fibers, bast powder, hemp shives, or derivatives thereof can be the active material of one or more components (e.g., electrodes) of the capacitor.

[0061] For example, the phloem fiber and / or the rod core fiber can first undergo hydrothermal carbonization to decompose the initial yarn-like structure of the fiber into smaller fragments. The hydrothermal synthesis process can produce a relatively high oxygen content (e.g., oxygen-containing functional groups), making the yield susceptible to subsequent activation processes using activation reagents such as potassium hydroxide (KOH). After the hydrothermal process, the fiber can then be activated with, for example, KOH to penetrate the fiber and generate carbon nanosheets. The activation temperature can be at least about 600 degrees Celsius (°C), 650 °C, 700 °C, 705 °C, 710 °C, 715 °C, 720 °C, 725 °C, 730 °C, 735 °C, 740 °C, 745 °C, 750 °C, 755 °C, 760 °C, 765 °C, 770 °C, 775 °C, 780 °C, 785 °C, 790 °C, 795 °C, 800 °C or higher. Alternatively, the activation temperature can be less than or equal to about 800 °C, 790 °C, 780 °C, 770 °C, 760 °C, 750 °C, 740 °C, 730 °C, 720 °C, 710 °C, 700 °C, 650 °C, 600 °C or lower. The phloem fiber and / or the rod core fiber can be or can not be pretreated, such as to reduce the size or open the fiber structure.

[0062] The hydrothermal carbonization process can generate graphite flakes. The graphite flakes can have a diameter of at least about 10 micrometers (μm), 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm or larger. Alternatively, the diameter of the graphite flakes can be less than or equal to about 500 μm, 400 μm, 300 μm, 200 μm, 100 μm, 50 μm, 10 μm or smaller. The graphite flakes can have a thickness of at least about 0.1 μm, 1 μm, 10 μm, 20 μm, 40 μm, 80 μm, 100 μm, 120 μm, 150 μm or larger. Alternatively, the thickness of the graphite flakes can be less than or equal to about 150 μm, 120 μm, 100 μm, 80 μm, 40 μm, 20 μm, 10 μm, 1 μm, 0.1 μm or smaller. Alternatively or additionally, the hydrothermal carbonization of the phloem fiber, phloem powder, rod core fiber or rod core powder material can generate at least one stack of carbon nanosheets.

[0063] One or more exfoliation techniques can be used to process graphite flakes or at least one stack of carbon nanosheets from a hydrothermal carbonization process to produce at least one carbon nanosheet having a thickness of one carbon atom. The exfoliation technique can have high scalability, reproducibility, processability, and / or low production costs. One or more exfoliation techniques can utilize a hydrodynamic-based liquid-phase exfoliation (LPE) device. Suitable solvents for the LPE device can be organic solvents (e.g., N,N-dimethylformamide), surfactant / aqueous solutions, aromatic solvents, or ionic liquids. The LPE device can use hydrodynamics to subject the graphite flakes or at least one stack of carbon nanosheets to dispersion in a suitable solvent or a mixture of suitable solvents under strong shear forces. The strong shear forces can be sufficient to exfoliate or peel off at least one carbon nanosheet from at least one stack of carbon nanosheets. The LPE device utilizing hydrodynamics can be a vortex fluid device, a pressure-driven hydrodynamic device, or a rotary mixer-driven hydrodynamic device. The operating speed of the vortex fluid device can be at least about 10 revolutions per minute (r.p.m.), 100 r.p.m., 1,000 r.p.m., or 10,000 r.p.m. or higher. Alternatively, the operating speed can be less than or equal to about 10,000 r.p.m., 1,000 r.p.m., 100 r.p.m., 10 r.p.m., or lower. The pressure of the pressure-driven hydrodynamic device can be at least about 1 megapascal (MPa), 5 MPa, 10 MPa, 20 MPa, 30 MPa, 40 MPa, 50 MPa, 100 MPa, or higher. Alternatively, the pressure can be less than or equal to 100 MPa, 50 MPa, 40 MPa, 30 MPa, 20 MPa, 10 MPa, 5 MPa, or lower. The rotor speed of the rotary mixer-driven hydrodynamic device can be at least about 10 r.p.m., 100 r.p.m., 1,000 r.p.m., or 10,000 r.p.m. or higher. Alternatively, the rotor speed can be less than or equal to about 10,000 r.p.m., 1,000 r.p.m., 100 r.p.m., 10 r.p.m., or lower.

[0064] In another example, the phloem or core powder may contain micro-sized or nano-sized cellulose particles, such as microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), or cellulose nanocrystals (CNC) derived from the phloem or core. The powder may contain nanoparticles and / or microparticles. In some cases, MCC, NCC, and CNC can be separated and / or derived from the phloem or core via acid hydrolysis (e.g., hydrochloric acid hydrolysis). For example, phloem or core fibers can be dried to a moisture content of less than 10% (e.g., in an industrial oven) after harvesting and ground (e.g., via a cutting and grinding mill) to produce phloem or core powder (e.g., hemp phloem powder, kenaf phloem powder, hemp core powder, etc.). The powder can be subjected to alkali treatment and washing. In some cases, the alkali treatment and washing can include treating with a 4% (w / w) sodium hydroxide (NaOH) solution at 80 °C for about 2 hours, washing with distilled water, and filtering. The alkali treatment and washing can be repeated (e.g., 2 cycles, 3 cycles, 4 cycles, etc.). After the alkali treatment and washing, a bleaching treatment can be performed. In some cases, the bleaching treatment can include soaking in a solution containing equal parts of acetate buffer, a 1.7% (w / w) aqueous solution of chlorite, and distilled water, washing with distilled water, and filtering. The bleaching treatment can be repeated (e.g., 2 cycles, 3 cycles, 4 cycles, etc.). Then the phloem or core can be subjected to acid hydrolysis (e.g., hydrochloric acid hydrolysis, sulfuric acid hydrolysis, etc.). In some cases, the acid hydrolysis can include subjecting 4%-6% (w / w) bleached fibers to a 60-minute treatment in preheated 65% sulfuric acid at 50 °C, mixing the suspension (e.g., via a magnetic stirrer), then separating via centrifugation at 4000 revolutions per minute (rpm) for 30 minutes, and dialyzing with distilled water. The whisker suspension can be homogenized to produce nanocellulose whiskers derived from the phloem or core. In another example, NCC or CNC (e.g., nanoparticles) can be prepared using cellulose separated from the phloem or core via acid hydrolysis (e.g., hydrochloric acid hydrolysis, sulfuric acid hydrolysis). The micron powder or nano powder derived from the phloem or core may exhibit properties such as high aspect ratio, high surface area, and high modulus. In some cases, the phloem powder may contain particles in the nano or micron range. For example, the phloem powder or core powder particles can have a diameter of at least about 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400, 450, 500 nanometers (nm) or greater. Alternatively, the phloem powder or core powder particles can have a diameter of at most about 500, 450, 400, 350, 300, 250, 150, 100, 90, 80, 70, 60, 50 nm or less.Alternatively, the phloem powder or the hurd powder particles can have a diameter of at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400, 450, 500 micrometers (μm) or greater. Alternatively, the phloem powder or the hurd powder particles can have a diameter of at most about 500, 450, 400, 350, 300, 250, 150, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10 μm or less.

[0065] In view of the above considerations, the capacitor can at least partially include phloem fibers, phloem powder, hemp hurd (e.g., fibers, powder, etc.) or derivatives thereof. For example, one or both of the two electrodes can comprise phloem fibers, phloem powder, hemp hurd or derivatives thereof. In some cases, the phloem fiber-based, phloem powder-based or hemp hurd-based electrodes can comprise carbon nanosheets or carbon nanotubes that contain a high level of mesoporosity that exhibits favorable electrochemical properties in a conventional ionic liquid electrolyte. Alternatively or additionally, the dielectric or at least a portion of the dielectric can include phloem fibers, phloem powder, hemp hurd or derivatives thereof. For example, a bilayer of NFC and CNC can be used as the dielectric in a supercapacitor. In some cases, the CNC and NFC dielectrics can be deposited on each electrode by spraying a thin film of a CNC solution (e.g., 0.8 wt% aqueous solution), drying the CNC film (e.g., at 60 °C), drop-casting an NFC gel (e.g., 0.8 wt% aqueous solution), and dehydrating the dried gel (e.g., at room temperature). A mechanical mask (e.g., a polydimethylsiloxane (PDMS) mask) can be used during deposition.

[0066] In some cases, the capacitor can at least partially include hemp (e.g., Cannabis sativa L.) phloem fibers, hemp phloem powder, hemp hurd (fibers or powder) or derivatives thereof. Hemp fibers (e.g., phloem fibers, hurd fibers, etc.) can comprise one or more layers of cellulose, hemicellulose and lignin. In particular, hemp fibers can include layered microfibrils composed of crystalline cellulose fibrils. During the hydrothermal process of hemp fibers (e.g., carried out at about 170 °C - 200 °C), in addition to other reactions (e.g., lignin hydrolysis, dehydration, decomposition, condensation, etc.), the crystalline cellulose may be partially carbonized. The hydrothermal process can loosen the interconnected layers of cellulose microfibrils while converting most of the hemicellulose and part of the lignin into soluble organic compounds. The hemicellulose and lignin can be dissolved to isolate the loose cellulose microfibrils.

[0067] During subsequent activation processes (e.g., carried out at about 700 °C - 800 °C), activation reagents such as KOH can penetrate the loose microfibril layer and thereby separate the layer into sheets. KOH can also carbonize and activate the separated layers to reduce their respective thicknesses and generate microporosity and mesoporosity in the carbon sheet structure. In particular, the crystalline cellulose content of the hemp precursor allows the derivatives formed by the KOH activation process to include a degree of orientation (e.g., the order state of graphite) in their structural properties. Alternatively, a pyrolysis process can be used to synthesize bast or core fiber derivatives.

[0068] The resulting hemp fiber derivatives can include carbon nanosheets with good microporosity, mesoporosity, and degree of graphite orientation for use in capacitor systems. In some cases, such fibers (e.g., pure hemp) or their derivatives (e.g., graphene-like carbon nanosheets) can be used as the first conductive material for the first electrode (e.g., Figure 1 the material of the first electrode 104 in Figure 1 ), the second conductive material for the second electrode (e.g.,

[0069] the material of the second electrode 108 in Figure 1 ), or the conductive material for both the first electrode and the second electrode. A dielectric, electrolyte, and / or separator can be placed between the first electrode and the second electrode to complete the capacitor. Alternatively, bast, core, or fiber bundle fibers can be obtained from flax, ramie, jute, kenaf, lime tree, linden, and / or other plants.

[0070] In some cases, the operating temperature can be changed to vary the resistance and / or dielectric constant. For example, the operating temperature can be at most about -50°C, -40°C, -30°C, -20°C, -10°C, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C or higher. Alternatively, the operating temperature can be less than or equal to 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, 60°C, 50°C, 40°C, 30°C, 20°C, 10°C, 0°C, -10°C, -20°C, -30°C, -40°C, -50°C or lower. In some cases, the phloem material can be configured to operate with a varying resistance and / or dielectric constant over a certain humidity range and / or a certain operating temperature range. In some cases, the thickness, surface quality, density (e.g., number of threads per unit length), and / or other configurations (e.g., warp and weft) of the woven structure in the cellulose fibers in the phloem or the rod core fibers can be changed to vary the resistance and / or dielectric constant.

[0071] In some cases, such phloem or rod core materials (e.g., pure hemp) or their derivatives (e.g., graphene-like carbon nanosheets, phloem fiber-reinforced polymer composites, CNC, NCC, etc.) can be used as dielectric materials (e.g., Figure 1 the dielectric 106 in). For example, one or more phloem or rod core fibers or powders (e.g., hemp, jute, etc.) can be used to reinforce a polymer (e.g., pure polypropylene, pure unsaturated polyester material, etc.) to form a hybrid fiber or powder composite with a relatively high dielectric constant (e.g., dielectric constant). A first electrode and a second electrode, each having a higher conductivity than the dielectric, can each be placed adjacent to the dielectric, where the first electrode and the second electrode are electrically isolated from each other.

[0072] In some cases, the phloem material, rod core material, or their derivatives can undergo processes such as electrospinning, solution casting, melt processing, and / or in-situ polymerization processes to form polymer composites with desired material properties such as a large surface-to-volume ratio. For example, electrospinning can control the deposition and dispersion of highly attractive nanomaterials such as graphene, carbon nanosheets, carbon nanotubes, graphene nanoribbons, and other carbon nanofiber composites. By electrospinning, carbon fibers with a diameter of less than one micron can be formed with relatively high control.

[0073] An electrospinning device may include a polymer solution, a high-voltage power supply, a needle (e.g., a spinneret, a nozzle, etc.), and an electrode collector. The high-voltage power supply may be any application unit configured to generate a strong electric field. The polymer solution may leave the container through the needle. The electrode collector may be disposed at a certain distance from the tip of the needle. The polymer solution and the electrode collector may be subjected to a strong electric field, such as by applying the high-voltage power supply. Small droplets of the polymer solution may leave the needle. When the electric force in the electric field overcomes the surface tension of the small droplets of the polymer solution, the small droplets may elongate in a substantially whip-like trajectory to form a solution jet or a focused fluid stream. Under the guidance of the strong electric field, the solution jet may bend or meander to be stretched thinner. Thereafter, the evaporation of the solvent from the jet may result in dry or semi-dry fibers, which may be randomly deposited onto the electrode collector to form a nanofiber web. The diameter of the electrospun fibers may be on the order of about one micrometer to about ten nanometers. The relatively small fiber diameter and large aspect ratio of the resulting fibers may result in a significantly higher surface-to-volume ratio.

[0074] In some cases, in addition to the strong electric field, the small droplets may also be subjected to a high-speed circumferentially uniform gas flow, such as in a gas-assisted electrospinning (GAES) system. The GAES system may provide a much higher fiber throughput, finer fibers, enhanced stretching of the fluid jet, and better control of guiding the fibers to the collector with less electrical interference between nearby or adjacent nozzles, for example.

[0075] The input polymer solution may contain a certain amount of well-dispersed fibers (e.g., bast, rod core, etc.) or their derivatives, such as graphene, carbon nanosheets, carbon nanotubes, graphene nanoribbons, and other carbon nanofiber composites. In some cases, the polymer / dispersion solution may be prepared by separately preparing the polymer solution and the dispersion solution and mixing them together. The polymer / dispersion solution may be a homogeneous solution. Electrospinning the polymer / dispersion solution may generate the resulting nanocomposite fibers with well-dispersed embedded nanostructures. For example, electrospinning a carbon nanotube (CNT) / polymer composite may result in nanocomposite fibers with better orientation, where the CNTs are oriented substantially parallel to the nanofiber axis. In some cases, the stable dispersion of CNTs may be achieved by using surfactants (e.g., sodium dodecyl sulfate), larger amphiphilic polymers (e.g., polyvinylpyrrolidone), and / or natural macromolecules (e.g., polysaccharides, gum arabic) that can be adsorbed onto the hydrophobic nanotubes. In some cases, dispersion may be promoted via sonication of the solution.

[0076] Advantageously, electrospun bast fiber / polymer composites (e.g., CNT / polymer composites) can exhibit significantly improved mechanical and electrical properties, which are suitable for use in the capacitors and / or supercapacitors described herein. The improved dispersion and orientation of nanotubes in the polymer fibers and the strong interfacial bonding resulting from nanotube surface modification can significantly improve the tensile strength and Young's modulus of the polymer. The fiber / polymer composites may also have improved resistance to mechanical strain (e.g., fracture strain), such as due to nanopores on the fiber surface shielding slippage and stress, and the highly oriented nanotubes along the fiber axis bearing the mechanical load from the polymer matrix. Additionally, the presence of conductive natural fibers (e.g., bast fibers, stalk core fibers, etc.) or fiber derivatives in the fiber / polymer composites can provide a way to improve the conductivity of polymers that are otherwise relatively poor in conductivity for various applications.

[0077] Nanofiber natural fiber / polymer composites can be used as materials in the capacitors or supercapacitors described herein, such as for electrodes and / or dielectrics.

[0078] In some cases, electrodes, dielectrics, and / or entire capacitors can be produced and / or assembled via three-dimensional (3D) printing, where fibers or powders of bast or stalk core materials (e.g., hemp, flax, etc.) are input and / or output materials. The 3D printing can be 3D nanoscale printing. For example, the individual components of a capacitor can be printed layer by layer with high modularity and flexibility onto a desired location (e.g., panel, wing, fabric, etc.).

[0079] Capacitors that at least partially comprise bast fibers, bast powders, stalk core fibers, stalk core powders, or derivatives thereof can have a mass of at most about 10 grams (g), 20 g, 30 g, 40 g, 50 g, 100 g, 200 g, 300 g, 400 g, 500 g, 600 g, 700 g, 800 g, 900 g, 1 kilogram (kg), 1.1 kg, 1.2 kg, 1.3 kg, 1.4 kg, 1.5 kg, 2 kg, 3 kg, 4 kg, 5 kg, 6 kg, 7 kg, 8 kg, 9 kg, 10 kg, 15 kg, 20 kg, 30 kg, or higher. In some cases, the mass of the capacitor can be adjusted to meet the power requirements of a specific type of electrical load (circuit of a power grid, smart grid, or vehicle, fuel vehicle, electric vehicle, airplane, jet, train, tram, ship, motorboat, electronic device, renewable energy harvesting and / or storage system, etc.) that is electrically coupled to the capacitor.

[0080] Figure 2Illustrated is a method of storing electrical energy using a natural fiber or powder capacitor. At a first operation 201, a capacitor including phloem fiber, phloem powder, rod core, or derivatives thereof is activated. The capacitor can at least partially comprise phloem fiber, phloem powder, rod core, or derivatives thereof. In some cases, the first electrode, the second electrode, or both the first and second electrodes of the capacitor can include phloem fiber, phloem powder, rod core, or derivatives thereof. In other cases, the dielectric of the capacitor can include phloem fiber, phloem powder, rod core, or derivatives thereof. In still other cases, both the dielectric of the capacitor and one or both of the electrodes can include phloem fiber, phloem powder, rod core, or derivatives thereof. For example, the capacitor can entirely include phloem material (e.g., fiber, powder), phloem-derived products, rod core material (e.g., fiber, powder), or rod core-derived products. In some cases, one or both of the electrodes can include phloem or rod core derivatives (e.g., graphene-like derivatives of hemp phloem or rod core fibers), and the dielectric can include pure phloem or rod core material (e.g., pure hemp fiber) or a mixture of phloem or rod core materials (e.g., with or without synthetic fibers, powders, etc.).

[0081] The first and second electrodes can be electrically isolated from each other such that no electrons conduct directly to or from the two electrodes. The dielectric can be placed adjacent to and between each of the first and second electrodes. In some cases, for a supercapacitor, the dielectric can include an electrolyte and / or a separator soaked in the electrolyte. The first and second electrodes can each be in contact with the electrolyte and be configured not to chemically react with the electrolyte. For example, a plurality of ions present in the electrolyte can accumulate at the electrode-electrolyte interface.

[0082] Once the capacitor is activated, at the next operation 202, the capacitor can be electrically connected to an electrical load and / or a power source. For example, the terminals of the first electrode, the terminals of the second electrode, and the electrical load and / or the power source can be electrically connected to the same circuit (e.g., via wires). Next at 203, the capacitor can be charged or discharged via the electrical load and / or the power source. In some cases, the capacitor can be electrically connected to a power source that charges the capacitor. For example, the power source can be a backup energy storage system (e.g., a battery) or a power supply. In other cases, the capacitor can be electrically connected to an electrical load that consumes electrical power and discharges the capacitor.

[0083] Figure 3A schematic diagram showing a capacitor 304 electrically connected to an electrical load 302 is shown. In some cases, when the first and second electronic components are components of the same circuit, the first electronic component (e.g., capacitor, electrical load, etc.) can be electrically connected to the second electronic component. The electrical load 302 can be an electrical grid or a circuit of a vehicle, aircraft, jet, train, tram, ship, electronic device, electrical grid, smart grid, or another device capable of consuming or generating electricity. Examples of vehicles include fuel-powered vehicles, electric vehicles, hybrid gas / electric vehicles, motorboats, or other electric or non-electric vehicles. The electronic device can be a personal computer (e.g., portable PC, desktop PC, etc.), tablet or tablet-type PC (e.g., Galaxy Tab, etc.), phone, smartphone (e.g., iPhone, Android-supported device, etc.), or personal digital assistant. For example, the capacitor 304 can be used to power an electrical load that requires short and powerful power bursts, such as starting an engine, braking, and / or providing acceleration in the wheels of a vehicle or other transportation unit (e.g., aircraft). For example, a plane electrically connected to the capacitor 304 can receive sufficient power bursts to accelerate its wheels during takeoff and / or near takeoff, thereby shortening the runway length required for takeoff.

[0084] The capacitor 304 can be used to power various high-processing and high-computation systems. For example, the capacitors of the present disclosure can power a computing system applied to any heavy processing work, such as a blockchain mining system (e.g., for cryptocurrency tokens, etc.), artificial intelligence system, quantum system, machine learning system, cryptographic system (including any decryption method), network operating system, high-definition graphics system, or other large systems. Alternatively or additionally, the capacitor can be used to significantly cool the above systems and prevent overheating.

[0085] The capacitor 304 can be used to power various horizontal takeoff and landing (HOTOL) or vertical takeoff and landing (VTOL) aircraft systems. For example, the propellers, aircraft propellers, and marine propellers used for takeoff, flight, or landing can be powered by the capacitors of the present disclosure. The propellers, aircraft propellers, and marine propellers can be electric or hybrid gas / electric. The HOTOL aircraft system can be a distributed electric propulsion system. The VTOL aircraft system can be an unmanned aerial vehicle (UAV), such as a drone. The UVA can be remotely flown by a pilot at a remote location using radio frequencies or fly autonomously following a pre-programmed flight. The aircraft system powered by the capacitor 304 can be used as a transportation system to transport at least one passenger, cargo, or both.

[0086] The capacitor 304 can be incorporated into wearable textiles for wearable energy storage. In some cases, phloem or rod core materials or their derivatives (e.g., carbon nanosheets) can be integrated as part of the dielectric material in two-dimensional supercapacitors (e.g., wires, yarns, etc.) with a high aspect ratio. The two-dimensional supercapacitor can be flexible. The two-dimensional supercapacitor can be woven into wearable textiles for wearable energy storage to power and / or charge various computing systems or electronic devices. The wearable textiles can include gloves, socks, shirts, ties, belts, and military vests. The various computing systems or electronic devices can be part of the wearable textiles (e.g., temperature sensors, heaters, light-emitting diode displays, heart rate monitors, fitness trackers, etc.) or separate portable devices (e.g., mobile devices, smartwatches, smart glasses, fitness trackers, etc.). The two-dimensional supercapacitor can be a micro-supercapacitor having a cross-sectional dimension of at least 0.1, 1, 10, 100, 1000 microns or greater. The two-dimensional supercapacitor can be composed of a layered structure of a conductive material and a phloem material or its derivatives, among others. The layered structure can be a layer-by-layer (LBL) assembly. In an example, a bilayer film including a conductive layer having at least one conductive polymer and a dielectric layer including at least phloem and / or rod core material or its derivatives can be rolled into a two-dimensional supercapacitor yarn. The bilayer film can be rolled into a two-dimensional supercapacitor yarn using an actuator. The dielectric layer can include phloem fibers oriented along the length of the two-dimensional supercapacitor yarn. The dielectric layer can also include a liquid or solid electrolyte and / or a separator. The dielectric layer can contain microporosity and / or mesoporosity with a beneficial degree of air as a separator. The two-dimensional supercapacitor yarn can include multiple LBL assemblies of the conductive layer and the dielectric layer. The two-dimensional supercapacitor yarn can have at least about 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100 or more LBL assemblies of the conductive layer and the dielectric layer.

[0087] In some cases, the capacitor 304 can be integrated as part of a power grid or smart grid for an area as large as a city or multiple cities. In some cases, the electrical load 302 can be an alternative and / or renewable energy harvesting or storage system, such as but not limited to solar, wind, water, geothermal, and gravity-assisted power generation systems. In some cases, the capacitor 304 can be used as a power buffer for an energy harvesting or storage system.

[0088] In some cases, the same electrical load (e.g., a vehicle, an energy harvesting or storage system, etc.) can both charge and discharge the capacitor, such as for different applications of the electrical load.

[0089] In some cases, the first electrical load can charge the capacitor, and the second electrical load can discharge the capacitor. The circuit including the capacitor 304 and the electrical load 302 may include other electrical components (e.g., switches, transistors, regulators, etc.) to facilitate the electrical connection between the capacitor 304 and the electrical load 302. In some cases, the capacitor 304 may be electrically connected to multiple electrical loads.

[0090] In some cases, the electrical load 302 may be electrically connected to multiple capacitors 304, where the capacitors 304 are connected continuously in series, continuously in parallel, and / or discontinuously. In some cases, the circuit may include multiple capacitors and multiple electrical loads. In some cases, the circuit may include multiple power sources (e.g., fuel cells, batteries, other capacitors, etc.) including the capacitor 304. The circuit architecture of any of the circuits described above or further below is not limited to Figure 3 the circuit architecture shown in the schematic diagram.

[0091] Capacitors including phloem fibers, phloem powder, rod cores, or derivatives thereof may be capable of charging or discharging at temperatures of at least about -100°C, -50°C, -40°C, -30°C, -20°C, -10°C, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 200°C, 250°C, 300°C, 350°C, or higher. Alternatively, the capacitor may be capable of charging or discharging at temperatures less than or equal to 350°C, 300°C, 250°C, 200°C, 150°C, 100°C, 90°C, 80°C, 70°C, 60°C, 50°C, 40°C, 30°C, 20°C, 10°C, 0°C, -10°C, -20°C, -30°C, -40°C, -50°C, -100°C, or lower. In some cases, the capacitor may be capable of charging or discharging within a temperature range of, for example, about 60°C - 100°C. For example, at temperatures below a certain temperature, the rate of charging and / or discharging may be limited. For example, at temperatures above a certain temperature, the capacitor may become unstable (e.g., due to the thermal stability and flammability of the electrode material and / or dielectric material). In some cases, the capacitor may have better performance (e.g., higher power density, higher energy density, etc.) in a certain temperature range (e.g., 60°C - 100°C) than in another temperature range.

[0092] In some cases, for a temperature range of about 60°C - 100°C, the capacitor can be configured to have a power density of at least about 55 kilowatts per kilogram (kW / kg) of effective mass. The relatively high power density can allow the capacitor to recharge and / or supply a certain amount of electrical energy in a relatively short period of time. Alternatively, the capacitor can have a power density of at least about 1 kW / kg, 5 kW / kg, 10 kW / kg, 15 kW / kg, 20 kW / kg, 25 kW / kg, 50 kW / kg, 55 kW / kg, 60 kW / kg, 65 kW / kg, 70 kW / kg, 75 kW / kg, 80 kW / kg, 85 kW / kg, 90 kW / kg, 95 kW / kg, 100 kW / kg, 110 kW / kg, 120 kW / kg, 130 kW / kg, 140 kW / kg, 150 kW / kg, 200 kW / kg, 250 kW / kg, 300 kW / kg, 350 kW / kg, 400 kW / kg or higher. In some cases, the capacitor can have a higher power density in one temperature range than in another temperature range.

[0093] In some cases, for a temperature range of about 60 °C to 100 °C, the capacitor can be configured to have an energy density of at least about 40 watt-hours per kilogram (Wh / kg) of effective mass. The relatively high energy density can allow the capacitor to store a relatively high amount of energy in a fixed amount of effective mass (e.g., per capacitor). Alternatively, the capacitor can have an energy density of at least about 1 Wh / kg, 5 Wh / kg, 10 Wh / kg, 15 Wh / kg, 20 Wh / kg, 25 Wh / kg, 50 Wh / kg, 55 Wh / kg, 60 Wh / kg, 65 Wh / kg, 70 Wh / kg, 75 Wh / kg, 80 Wh / kg, 85 Wh / kg, 90 Wh / kg, 95 Wh / kg, 100 Wh / kg, 110 Wh / kg, 120 Wh / kg, 130 Wh / kg, 140 Wh / kg, 150 Wh / kg, 200 Wh / kg, 250 Wh / kg, 300 Wh / kg, 350 Wh / kg, 400 Wh / kg or higher. Such an energy density can be in at least about 10, 25, 50, 75, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000 or more charge / discharge cycles of the capacitor. In some cases, the capacitor can have a higher energy density in one temperature range than in another temperature range.

[0094] In some cases, for a temperature range of about 60°C - 100°C, the capacitor can be configured to withstand at least about 250 charge / discharge cycles while maintaining a power density of at least about 55 kW / kg of effective mass and / or an energy density of at least about 40 Wh / kg of effective mass. The more charge / discharge cycles the capacitor can withstand, the longer the capacitor can remain in the circuit without replacement. Alternatively, the capacitor can maintain a power density of at least about 55 kW / kg of effective mass and / or an energy density of at least about 40 Wh / kg of effective mass in at least about 10, 25, 50, 75, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000 or more charge / discharge cycles. Alternatively, the capacitor can maintain a power density of at least about 75 kW / kg of effective mass and / or an energy density of at least about 60 Wh / kg of effective mass in at least about 10, 25, 50, 75, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000 or more charge / discharge cycles. Alternatively, the capacitor can maintain a power density of at least about 100 kW / kg of effective mass and / or an energy density of at least about 80 Wh / kg of effective mass in at least about 10, 25, 50, 75, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000 or more charge / discharge cycles. In some cases, the capacitor can withstand more charge / discharge cycles in one temperature range than in another temperature range.

[0095] In some cases, for a temperature range of about 60°C - 100°C, the capacitor can be configured to have a charge and / or discharge time of less than about 10 seconds. Alternatively, the capacitor can have a charge / discharge time of at most about 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.1, 0.01 seconds or less. In some cases, the capacitor can have a higher energy density within a certain temperature range than within another temperature range.

[0096] One or more components of the capacitors described herein, such as electrodes or dielectric materials comprising bast fibers, bast powder, rod cores, or derivatives thereof, can be used as components of other power or energy storage systems such as batteries (e.g., solid-state batteries), fuel cells, electrochemical cells, rechargeable batteries (e.g., secondary batteries), or other storage systems. For example, a battery can include one or more electrodes comprising bast fibers, bast powder, rod cores, or derivatives thereof, such as the electrodes for capacitors described elsewhere herein. The bast fibers, bast powder, rod cores, or derivatives thereof can be the active material of the electrodes. In some cases, a battery can include an electrode comprising bast fibers, bast powder, rod cores, or derivatives thereof. In some cases, a battery can include two electrodes, each comprising bast fibers, bast powder, rod cores, or derivatives thereof of the same or different compositions. The power or energy storage system can include materials derived from other plants (e.g., derived from cannabis, derived from flax, etc.).

[0097] The present invention provides the following embodiments including but not limited to:

[0098] 1. A capacitor for storing electrical energy, comprising:

[0099] A first electrode formed of a material capable of conducting electrons to or from an electrical load;

[0100] A dielectric adjacent to the first electrode, wherein the dielectric is formed of bast or rod core material or a derivative thereof; and

[0101] A second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from the electrical load, and wherein the second electrode is electrically isolated from the first electrode,

[0102] wherein the capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0103] 2. The capacitor according to Embodiment 1, wherein the capacitor has a power density of at least about 75 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0104] 3. The capacitor according to Embodiment 2, wherein the capacitor has a power density of at least about 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0105] 4. The capacitor according to Embodiment 1, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0106] 5. The capacitor according to Embodiment 4, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 1000 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0107] 6. The capacitor according to Embodiment 5, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 2000 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0108] 7. The capacitor according to Embodiment 1, wherein the electrical load is a power grid.

[0109] 8. The capacitor according to Embodiment 1, wherein the electrical load includes a vehicle's circuit.

[0110] 9. The capacitor according to Embodiment 1, wherein the electrical load includes an aircraft's circuit.

[0111] 10. The capacitor according to Embodiment 1, wherein the electrical load includes a train's circuit.

[0112] 11. The capacitor according to Embodiment 1, wherein the electrical load includes a ship's circuit.

[0113] 12. The capacitor according to Embodiment 1, wherein the dielectric is formed of the bast material.

[0114] 13. The capacitor according to Embodiment 12, wherein the bast material is hemp bast or kenaf bast.

[0115] 14. The capacitor according to Embodiment 1, wherein the dielectric is formed of the rod core material.

[0116] 15. The capacitor according to Embodiment 14, wherein the core material of the rod is hemp core or kenaf core.

[0117] 16. The capacitor according to Embodiment 1, wherein the dielectric includes a rod core or a derivative thereof.

[0118] 17. The capacitor according to Embodiment 1, wherein the capacitor has a mass of at most about 5 kg.

[0119] 18. The capacitor according to Embodiment 17, wherein the capacitor has a mass of at most about 2 kg.

[0120] 19. The capacitor according to Embodiment 1, wherein the capacitor has an energy density of at least about 40 watt-hours (Wh) / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0121] 20. The capacitor according to Embodiment 19, wherein the capacitor has an energy density of at least about 60 Wh / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0122] 21. The capacitor according to Embodiment 1, wherein the phloem and / or core material of the rod is phloem and / or core fiber, or phloem and / or core powder.

[0123] 22. A method for storing electrical energy, comprising:

[0124] (a) Activating a capacitor, the capacitor comprising (i) a first electrode formed of a material capable of conducting electrons to or from an electrical load; (ii) a dielectric adjacent to the first electrode, wherein the dielectric is formed of phloem fiber, phloem powder, or a derivative thereof; and (iii) a second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from the electrical load, and wherein the second electrode is electrically isolated from the first electrode, and wherein the capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass in at least about 250 charge / discharge cycles at a temperature of 60°C - 100°C;

[0125] (b) Electrically connecting the capacitor to the electrical load; and

[0126] (c) Charging or discharging the capacitor via the electrical load.

[0127] 23. The method according to embodiment 22, wherein the capacitor has a power density of at least about 75 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0128] 24. The method according to embodiment 23, wherein the capacitor has a power density of at least about 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0129] 25. The method according to embodiment 22, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0130] 26. The method according to embodiment 25, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0131] 27. The method according to embodiment 26, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0132] 28. The method according to embodiment 22, wherein the electrical load is a power grid.

[0133] 29. The method according to embodiment 22, wherein the electrical load includes the circuitry of a vehicle.

[0134] 30. The method according to embodiment 22, wherein the electrical load includes the circuitry of an aircraft.

[0135] 31. The method according to embodiment 22, wherein the electrical load includes the circuitry of a train.

[0136] 32. The method according to embodiment 22, wherein the electrical load includes the circuitry of a ship.

[0137] 33. The method according to embodiment 22, wherein the dielectric is formed of bast fibers.

[0138] 34. The method according to embodiment 33, wherein the bast fibers are hemp bast fibers.

[0139] 35. The method according to embodiment 22, wherein the dielectric is formed of bast powder.

[0140] 36. The method according to embodiment 35, wherein the phloem powder is hemp phloem powder or kenaf phloem powder.

[0141] 37. The method according to embodiment 22, wherein the dielectric includes a rod core or a derivative thereof.

[0142] 38. The method according to embodiment 22, wherein the capacitor has a mass of at most about 5 kg.

[0143] 39. The method according to embodiment 38, wherein the capacitor has a mass of at most about 2 kg.

[0144] 40. The method according to embodiment 22, wherein the capacitor has an energy density of at least about 40 watt-hours (Wh) / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0145] 41. The method according to embodiment 40, wherein the capacitor has an energy density of at least about 60 Wh / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0146] 42. A capacitor for storing electrical energy, comprising:

[0147] A first electrode formed of a material capable of conducting electrons to or from an electrical load;

[0148] A dielectric adjacent to the first electrode, wherein the dielectric is formed of a material having a lower electrical conductivity than the material of the first electrode; and

[0149] A second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from an electrical load, and wherein the second electrode is electrically isolated from the first electrode,

[0150] wherein the first electrode, the second electrode, or both the first electrode and the second electrode are formed of phloem and / or rod core material, and

[0151] wherein the capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0152] 43. The capacitor according to Embodiment 42, wherein the capacitor has a power density of at least about 75 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0153] 44. The capacitor according to Embodiment 43, wherein the capacitor has a power density of at least about 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0154] 45. The capacitor according to Embodiment 42, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0155] 46. The capacitor according to Embodiment 45, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0156] 47. The capacitor according to Embodiment 46, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0157] 48. The capacitor according to Embodiment 42, wherein the electrical load is a power grid.

[0158] 49. The capacitor according to Embodiment 42, wherein the electrical load includes the circuitry of a vehicle.

[0159] 50. The capacitor according to Embodiment 42, wherein the electrical load includes the circuitry of an aircraft.

[0160] 51. The capacitor according to Embodiment 42, wherein the electrical load includes the circuitry of a train.

[0161] 52. The capacitor according to Embodiment 42, wherein the electrical load includes the circuitry of a ship.

[0162] 53. The capacitor according to Embodiment 42, wherein the first electrode is formed of bast fibers.

[0163] 54. The capacitor according to Embodiment 53, wherein the bast fibers are hemp bast fibers.

[0164] 55. The capacitor according to Embodiment 42, wherein the first electrode is formed of bast fiber powder.

[0165] 56. The capacitor according to Embodiment 55, wherein the bast fiber powder is cannabis bast fiber powder or kenaf bast fiber powder.

[0166] 57. The capacitor according to Embodiment 42, wherein the first electrode comprises a rod core or a derivative thereof.

[0167] 58. The capacitor according to Embodiment 42, wherein the capacitor has a mass of at most about 5 kg.

[0168] 59. The capacitor according to Embodiment 58, wherein the capacitor has a mass of at most about 2 kg.

[0169] 60. The capacitor according to Embodiment 42, wherein the capacitor has an energy density of at least about 40 Wh / kg effective mass at a temperature of 60°C - 100°C in at least about 250 charge / discharge cycles via the electrical load.

[0170] 61. The capacitor according to Embodiment 60, wherein the capacitor has an energy density of at least about 60 Wh / kg effective mass at a temperature of 60°C - 100°C in at least about 250 charge / discharge cycles via the electrical load.

[0171] 62. A method for storing electrical energy, comprising:

[0172] (a) Activating a capacitor, the capacitor comprising (i) a first electrode formed of a material capable of conducting electrons to or from an electrical load; (ii) a dielectric adjacent to the first electrode, wherein the dielectric is formed of a material having a lower electrical conductivity than the material of the first electrode; and (iii) a second electrode adjacent to the dielectric, wherein the second electrode is formed of a material capable of conducting electrons to or from an electrical load, and wherein the second electrode is electrically isolated from the first electrode, wherein the first electrode, the second electrode, or both the first electrode and the second electrode are formed of bast fiber, bast fiber powder, or a derivative thereof, and wherein the capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) effective mass at a temperature of 60°C - 100°C in at least about 250 charge / discharge cycles via the electrical load;

[0173] (b) Electrically connecting the capacitor to the electrical load; and

[0174] (c) Charging or discharging the capacitor via the electrical load.

[0175] 63. The method according to embodiment 62, wherein the capacitor has a power density of at least about 75 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0176] 64. The method according to embodiment 63, wherein the capacitor has a power density of at least about 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0177] 65. The method according to embodiment 62, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0178] 66. The method according to embodiment 65, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0179] 67. The method according to embodiment 66, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0180] 68. The method according to embodiment 62, wherein the electrical load is a power grid.

[0181] 69. The method according to embodiment 62, wherein the electrical load includes the circuitry of a vehicle.

[0182] 70. The method according to embodiment 62, wherein the electrical load includes the circuitry of an aircraft.

[0183] 71. The method according to embodiment 62, wherein the electrical load includes the circuitry of a train.

[0184] 72. The method according to embodiment 62, wherein the electrical load includes the circuitry of a ship.

[0185] 73. The method according to embodiment 62, wherein the first electrode is formed of bast fibers.

[0186] 74. The method according to embodiment 73, wherein the bast fibers are hemp bast fibers.

[0187] 75. The method according to embodiment 62, wherein the first electrode is formed of bast powder.

[0188] 76. The method according to embodiment 75, wherein the bast powder is cannabis bast powder or kenaf bast powder.

[0189] 77. The method according to embodiment 62, wherein the first electrode comprises a rod core or a derivative thereof.

[0190] 78. The method according to embodiment 62, wherein the capacitor has a mass of at most about 5 kg.

[0191] 79. The method according to embodiment 78, wherein the capacitor has a mass of at most about 2 kg.

[0192] 80. The method according to embodiment 62, wherein the capacitor has an energy density of at least about 40 watt-hours (W·h) / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0193] 81. The method according to embodiment 80, wherein the capacitor has an energy density of at least about 60 watt-hours (W·h) / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0194] 82. A method of manufacturing a capacitor, comprising:

[0195] (a) obtaining bast and / or rod core material derived from a plant;

[0196] (b) processing the bast and / or rod core material into a processed material in the form of fibers or particles;

[0197] (c) using the processed material to generate a first electrode, a second electrode, and / or a dielectric; and

[0198] (d) assembling the first electrode, the second electrode, and the dielectric to produce the capacitor, the capacitor comprising (i) the first electrode, (ii) the dielectric adjacent to the first electrode, and (iii) the second electrode adjacent to the dielectric, wherein the second electrode is electrically isolated from the first electrode, and wherein the capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0199] 83. The method according to embodiment 82, wherein the plant is cannabis.

[0200] 84. The method according to embodiment 82, wherein the processing includes pulverizing the phloem and / or the rod core material to form particles containing the phloem and / or the rod core material.

[0201] 85. The method according to embodiment 82, wherein the phloem and / or the rod core material includes phloem and / or rod core fibers.

[0202] 86. The method according to embodiment 82, wherein the phloem and / or the rod core material is phloem material.

[0203] 87. The method according to embodiment 82, wherein the phloem and / or the rod core material is rod core material.

[0204] 88. The method according to embodiment 82, further comprising weaving the capacitor into a fabric.

[0205] 89. The capacitor according to embodiment 82, wherein the capacitor has a power density of at least about 75 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0206] 90. The capacitor according to embodiment 89, wherein the capacitor has a power density of at least about 100 kW / kg of effective mass in at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0207] 91. The capacitor according to embodiment 90, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0208] 92. The capacitor according to embodiment 91, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0209] 93. The capacitor according to embodiment 92, wherein the capacitor has a power density of at least about 55 kW / kg of effective mass in at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

[0210] 94. The capacitor according to embodiment 82, wherein the electrical load is a power grid.

[0211] 95. The capacitor according to embodiment 82, wherein the electrical load includes a circuit of a vehicle.

[0212] 96. The capacitor according to embodiment 82, wherein the capacitor has a mass of at most about 5 kg.

[0213] 97. The capacitor according to embodiment 96, wherein the capacitor has a mass of at most about 2 kg.

[0214] 98. The capacitor according to embodiment 82, wherein the capacitor has an energy density of at least about 40 Wh / kg effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0215] 99. The capacitor according to embodiment 98, wherein the capacitor has an energy density of at least about 60 Wh / kg effective mass in at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C - 100°C.

[0216] Embodiment

[0217] In an example, electrodes for a capacitor are formed by carbonizing and activating the hydrothermal product of hemp bast fibers. Hemp bast fibers and dilute sulfuric acid are sealed in a steel autoclave. The autoclave is heated at 180°C for 24 hours and then cooled to room temperature (e.g., about 20°C - 25°C). The contents of the autoclave are filtered, washed with distilled water, and dried to obtain a carbonaceous solid (e.g., biochar). The biochar and potassium hydroxide (KOH) are mixed at a mass ratio of 1:1, and the mixture is heated at 700°C - 800°C (e.g., 3°C / min) for 1 hour under an argon gas flow. The activated sample is then washed with 10 weight percent (wt%) hydrochloric acid (HCl) and distilled water. The carbon is dried in an oven at 100°C for 12 hours. The carbon nanosheets (CNS-700) activated at 700°C by the above process have a surface area density of 1690 square meters per gram (m 2 g -1 ), the carbon nanosheets (CNS-750) activated at 750°C by the above process have a surface area density of 2287 m 2 g -1 , and the carbon nanosheets (CNS-800) activated at 800°C by the above process have a surface area density of 1505 m 2 g -1 . The electrical conductivities of CNS-700, CNS-750, and CNS-800 are 217 siemens per meter (S m -1 ), 211 S m -1 and 226 S m-1 At a working temperature of 20 °C, CNS-750 and CNS-800 exhibit energy densities of 19 watt-hours per kilogram (Wh / kg) and 18 Wh / kg, respectively. -1 ) and 18 Wh / kg -1 At a working temperature of 60 °C, CNS-750 and CNS-800 exhibit energy densities of 34 Wh / kg -1 and 31 Wh / kg -1 respectively. At a working temperature of 100 °C, CNS-750 and CNS-800 exhibit energy densities of 40 Wh / kg -1 and 34 Wh / kg -1 respectively. The maximum power densities of CNS-800 at working temperatures of 20 °C, 60 °C, and 100 °C are 28 kilowatts per kilogram (kW / kg), -1 ) 49 kW / kg, -1 and 77 kW / kg -1 respectively. After 10,000 cycles, CNS-800 can retain 96% of its initial capacitance.

[0218] Although the preferred embodiments of the present invention have been shown and described herein, it will be readily apparent to those skilled in the art that these embodiments are provided by way of example only. The present invention is not limited by the specific examples provided in this specification. While the invention has been described in accordance with the foregoing specification, it is not meant to be construed in a limiting sense with respect to the description and illustration of the embodiments herein. Various changes, alterations, and substitutions will now occur to those skilled in the art without departing from the invention. In addition, it should be understood that all aspects of the present invention are not limited to the specific descriptions, configurations, or relative proportions described herein, which depend on various conditions and variables. It should be understood that various alternatives to the embodiments of the present invention described herein can be used to practice the present invention. Accordingly, it is intended that the present invention also cover any such alternatives, modifications, variations, or equivalents. The scope of the present invention is intended to be defined by the following claims and to cover the methods and structures and their equivalents falling within the scope of these claims.

Claims

1. A method of manufacturing a capacitor, which comprises: (a) obtaining a phloem or core material derived from a plant; (b) processing the phloem or core material into a processed material, the processed material being in the form of fibers or particles, and the processed material comprising stacked graphene-like nanosheets; (c) using the processed material to generate a dielectric, wherein the dielectric comprises a separator, and the separator comprises the processed material; and (d) assembling a first electrode, a second electrode and the dielectric to produce the capacitor, the capacitor comprising (i) the first electrode, (ii) the dielectric adjacent to the first electrode, and (iii) the second electrode adjacent to the dielectric, wherein the second electrode is electrically isolated from the first electrode, and wherein the capacitor has a power density of at least 55 kilowatts (kW) / kilogram (kg) of effective mass in at least 250 charge / discharge cycles via an electrical load at a temperature of 60°C - 100°C.

2. The method according to claim 1, wherein the plant is cannabis.

3. The method according to claim 1, wherein the processing comprises crushing the phloem or core material to form particles comprising the phloem or core material.

4. The method according to claim 1, wherein the phloem or core material comprises phloem or core fibers.

5. The method according to claim 1, wherein the phloem or core material is phloem material.

6. The method according to claim 1, wherein the phloem or core material is core material.

7. The method according to claim 1, wherein, the dielectric further comprises an electrolyte.

8. The method according to claim 1, further comprising using the processed material to produce the first electrode, the second electrode, or both the first electrode and the second electrode.

9. The method according to claim 1, wherein the processing comprises hydrothermal carbonization of the phloem or core material.

10. The method according to claim 9, further comprising treating the phloem or core material with an activating reagent to produce the processed material.

11. The method according to claim 10, wherein the activating reagent comprises potassium hydroxide.

12. The method according to claim 10, further comprising treating the phloem or core material with an activating reagent at a temperature of at least 600°C.

13. The method according to claim 1, wherein the processing comprises using liquid phase exfoliation, chemical vapor deposition, microwave synthesis, pyrolysis, or any combination thereof on the phloem or core material to produce the processed material.

14. The method according to claim 1, wherein the processing comprises using an alkali treatment, a bleaching treatment, an acid hydrolysis, or any combination thereof to produce the processed material.

15. The method according to claim 1, wherein assembling the capacitor comprises three-dimensional printing.

16. The method according to claim 1, wherein the dielectric is a composite material comprising the phloem or core material.

17. The method according to claim 16, wherein the processing includes electrospinning, solution casting, melt processing, or any combination thereof to produce the composite material.

18. The method according to claim 1, wherein the first electrode or the second electrode is a composite material comprising the bast or rod core material.

19. The method according to claim 1, further comprising weaving the capacitor into a fabric.

20. The method according to claim 1, wherein the capacitor has a power density of at least 75 kW / kg of effective mass in at least 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

21. The method according to claim 20, wherein the capacitor has a power density of at least 100 kW / kg of effective mass in at least 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

22. The method according to claim 1, wherein the capacitor has a power density of at least 55 kW / kg of effective mass in at least 500 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

23. The method according to claim 22, wherein the capacitor has a power density of at least 55 kW / kg of effective mass in at least 1000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

24. The method according to claim 23, wherein the capacitor has a power density of at least 55 kW / kg of effective mass in at least 2000 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

25. The method according to claim 1, wherein the electrical load is a power grid.

26. The method according to claim 1, wherein the electrical load includes the circuitry of a vehicle.

27. The method according to claim 1, wherein the capacitor has a mass of at most 5 kg.

28. The method according to claim 27, wherein the capacitor has a mass of at most 2 kg.

29. The method according to claim 1, wherein the capacitor has an energy density of at least 40 W·h / kg of effective mass in at least 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

30. The method according to claim 29, wherein the capacitor has an energy density of at least 60 Wh / kg of effective mass in at least 250 charge / discharge cycles via the electrical load at the temperature of 60°C - 100°C.

31. An electrode comprising a nanofiber and a polymer composite material, wherein the nanofiber comprises a bast or rod core material, wherein the bast or rod core material comprises stacked graphene-like nanosheets, and wherein the electrode is configured to conduct ions to or from an electrical load.

32. An electrode comprising a porous conductive material, wherein the porous conductive material comprises bast or rod core material, wherein the bast or rod core material comprises stacked graphene-like nanosheets, and wherein the electrode is configured to conduct ions to or from an electrical load.

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