System and method for strong electrical energy

Abstract

To provide systems and methods for suitable strong electrical energy.SOLUTION: The present disclosure provides capacitors for storing electrical energy. The capacitors can comprise, at least in part, bast fiber, bast powder, hard fiber, hard powder, or a derivative thereof. In some instances, a dielectric of a capacitor can be formed of the bast fiber, the bast powder, the hard fiber, the hard powder, or the derivative thereof. In other instances, one or both electrodes of the capacitor can be formed of the bast fiber, the bast powder, the hard fiber, the hard powder, or the derivative thereof. The resulting capacitors can have various power densities and various energy densities over various minimum numbers of charge / discharge cycles at a certain specified range of operating temperatures.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] (Cross-reference) This application claims the benefit of U.S. Provisional Patent Application No. 62 / 478,553, filed Mar. 29, 2017, and U.S. Provisional Patent Application No. 62 / 540,147, filed Aug. 2, 2017, each of which is hereby incorporated by reference in its entirety.

Background Art

[0002] Capacitors can have a higher power density and can thus release energy over shorter time periods than some alternative energy storage systems (e.g., batteries). A supercapacitor can be configured to store an amount of charge (and thereby electrical energy) that is several orders of magnitude greater than that stored by a normal capacitor while still having a higher power density. In some cases, the material properties of capacitors and supercapacitors, such as the materials for the electrodes and dielectrics of capacitors and supercapacitors, can affect capacitor performance. For example, in some cases, electrodes with a larger surface area can exhibit performance superior to electrodes with a smaller surface area. In another example, in some cases, dielectrics with a higher relative permittivity can exhibit performance superior to dielectrics with a lower relative permittivity.

Summary of the Invention

Means for Solving the Problems

[0003] Provided is a capacitor for storing electrical energy, the capacitor comprising at least in part, jute and / or bagasse or derivatives thereof. For example, the capacitor may include jute fibers, jute powder, bagasse fibers, bagasse powder, or derivatives thereof. In some embodiments, the dielectric of the capacitor can be formed from jute fibers, jute powder, bagasse fibers, bagasse powder, and / or derivatives thereof. In some embodiments, one or both electrodes of the capacitor can be formed from jute fibers, jute powder, bagasse fibers, bagasse powder, and / or derivatives thereof. The resulting capacitor can be configured to have various power densities and various energy densities and to withstand various minimum numbers of charge / discharge cycles in a defined operating temperature range.

[0004] In one aspect, a capacitor for storing electrical energy is provided, the dielectric of the capacitor being formed from jute or bagasse material or derivatives thereof. The capacitor includes a first electrode formed from a material capable of conducting electrons to or from an electrical load, a dielectric adjacent to the first electrode and formed from jute fibers, jute powder, or derivatives thereof, and a second electrode adjacent to the dielectric, the second electrode being formed from a material capable of conducting electrons to or from the electrical load and electrically isolated from the first electrode.

[0005] Electrical energy can be stored within a capacitor comprising a dielectric formed from jute or bagasse material or derivatives thereof by activating the capacitor, placing the capacitor in electrical communication with an electrical load, and charging or discharging the capacitor through the electrical load.

[0006] In some embodiments, at a temperature of 60°C to 100°C, the capacitor can have a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass, 75 kW / kg of effective mass, or 100 kW / kg of effective mass over at least about 250 charge / discharge cycles via an electrical load.

[0007] In some embodiments, at a temperature of 60°C to 100°C, the capacitor can have a power density of at least about 55 kW / kg of effective mass over at least about 250 charge / discharge cycles, 500 charge / discharge cycles, 1000 charge / discharge cycles, or 2000 charge / discharge cycles via an electrical load.

[0008] In some embodiments, at a temperature of 60°C to 100°C, the capacitor can have an energy density of at least about 40 watt-hours (Wh) / kg of effective mass or 60 Wh / kg of effective mass over at least about 250 charge / discharge cycles via an electrical load.

[0009] In some embodiments, the electrical load through which the electrodes of the capacitor conduct electrons to or from can be a power grid. Alternatively, the electrical load can include the electrical circuits of a vehicle, an airplane, a train, or a ship.

[0010] In some embodiments, the dielectric of the capacitor can be formed from a bast material such as jute 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 a shive (or chip) material such as hemp shive or kenaf shive. The shive material can be in the form of shive fibers or shive powder.

[0011] In some embodiments, the capacitor can have a mass of up to about 2 kg or 5 kg.

[0012] In another aspect, provided is a capacitor for storing electrical energy, wherein the first electrode, the second electrode, or both the first and second electrodes of the capacitor are formed from leather or sawdust material or derivatives thereof. The capacitor includes a first electrode formed from a material capable of conducting electrons to or from an electrical load, a dielectric adjacent to the first electrode and formed from a material having an electrical conductivity lower than that of the material of the first electrode, and a second electrode adjacent to the dielectric and formed from a material capable of conducting electrons to or from the electrical load and electrically isolated from the first electrode. The first electrode, the second electrode, or both the first and second electrodes are formed from leather or sawdust material or derivatives thereof.

[0013] Electrical energy can be stored in a capacitor having first and / or second electrodes formed from leather or sawdust material or derivatives thereof by activating the capacitor, electrically connecting the capacitor to an electrical load, and charging or discharging the capacitor through the electrical load.

[0014] In some embodiments, at a temperature of 60 °C to 100 °C, the capacitor can have a power density of at least about 55 kilowatts (kW) per kilogram (kg) of effective mass, 75 kW / kg of effective mass, or 100 kW / kg of effective mass over at least about 250 charge / discharge cycles through an electrical load.

[0015] In some embodiments, at a temperature of 60 °C to 100 °C, the capacitor can have a power density of at least about 55 kW / kg of effective mass over at least about 250, 500, 1000, or 2000 charge / discharge cycles through an electrical load.

[0016] In some embodiments, at a temperature of 60°C to 100°C, the capacitor can have an energy density of at least about 40 Wh / kg or 60 Wh / kg effective mass over at least about 250 charge / discharge cycles via an electrical load.

[0017] In some embodiments, the electrical load through which or from which the electrodes of the capacitor conduct electrons can be a power grid. Alternatively, the electrical load can include the electrical circuits of a vehicle, an airplane, a train, or a ship.

[0018] In some embodiments, the first and / or second electrodes of the capacitor can be formed from a tough skin material such as ramie tough skin or kenaf tough skin. The tough skin material can be in the form of tough skin fibers, tough skin powder, or derivatives thereof. In some embodiments, the first and / or second electrodes can include a sawdust (or fragments) material such as ramie sawdust or kenaf sawdust. The sawdust material can be in the form of sawdust fibers or sawdust powder.

[0019] In some embodiments, the capacitor can have a mass of up to about 2 kg or 5 kg.

[0020] In another aspect, provided is a method of manufacturing a capacitor, comprising: (a) obtaining bast and / or bagasse materials derived from plants; (b) processing the bast and / or bagasse materials into a processed material, wherein the processed material is in the form of fibers or particles; (c) using the processed material to produce a first electrode, a second electrode, and / or a dielectric; and (d) assembling the first electrode, the second electrode, and the dielectric to produce a capacitor comprising: (i) the first electrode; (ii) a dielectric adjacent to the first electrode; and (iii) a second electrode adjacent to the dielectric and electrically isolated from the first electrode, wherein the capacitor has a power density of at least about 55 kilowatts (kW) per kilogram (kg) of effective mass over at least about 250 charge / discharge cycles via an electrical load at a temperature of 60° C. to 100° C.

[0021] In some embodiments, the plant is cannabis.

[0022] In some embodiments, the processing comprises grinding the bast and / or bagasse materials to form particles comprising the bast and / or bagasse materials.

[0023] In some embodiments, the bast and / or bagasse materials comprise bast and / or bagasse fibers. In some embodiments, the bast and / or bagasse materials are bast materials. In some embodiments, the bast and / or bagasse materials are bagasse materials.

[0024] In some embodiments, the method further comprises weaving the capacitor into a fabric.

[0025] In some embodiments, the capacitor has a power density of at least about 75 kW / kg effective mass over at least about 250 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. In some embodiments, the capacitor has a power density of at least about 100 kW / kg effective mass over at least about 250 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg effective mass over at least about 500 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg effective mass over at least about 1000 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. In some embodiments, the capacitor has a power density of at least about 55 kW / kg effective mass over at least about 2000 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C.

[0026] In some embodiments, the electrical load is a power grid. In some embodiments, the electrical load includes the electrical circuit of a vehicle.

[0027] In some embodiments, the capacitor has a mass of up to about 5 kg. In some embodiments, the capacitor has a mass of up to about 2 kg.

[0028] In some embodiments, the capacitor has an energy density of at least about 40 W-hour (h) / kg effective mass over at least about 250 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. In some embodiments, the capacitor has an energy density of at least about 60 Wh / kg effective mass over at least about 250 charge / discharge cycles via an electrical load at a temperature of 60°C to 100°C. The present invention provides, for example, the following. (Item 1) A capacitor for storing electrical energy, A first electrode, wherein the first electrode is formed of a material capable of conducting electrons to or from the electrical load, the first electrode; A dielectric adjacent to the first electrode, wherein the dielectric is formed of a leather or sawdust material or a derivative thereof, the dielectric; 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 the second electrode is electrically isolated from the first electrode, the second electrode Comprising; The capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60 ° C to 100 ° C, the capacitor. (Item 2) The capacitor according to item 1, having 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 to 100 ° C. (Item 3) The capacitor according to item 2, having 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 a temperature of 60 ° C to 100 ° C. (Item 4) The capacitor according to item 1, having 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 a temperature of 60 ° C to 100 ° C. (Item 5) The capacitor according to item 4, having 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 to 100 ° C. (Item 6) The capacitor according to item 5 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 to 100°C. (Item 7) The capacitor according to item 1, wherein the electrical load is a power transmission network. (Item 8) The capacitor according to item 1, wherein the electrical load includes an electrical circuit of a vehicle. (Item 9) The capacitor according to item 1, wherein the electrical load includes an electrical circuit of an airplane. (Item 10) The capacitor according to item 1, wherein the electrical load includes an electrical circuit of a train. (Item 11) The capacitor according to item 1, wherein the electrical load includes an electrical circuit of a ship. (Item 12) The capacitor according to item 1, wherein the dielectric is formed from the bast material. (Item 13) The capacitor according to item 12, wherein the bast material is hemp bast or kenaf bast. (Item 14) The capacitor according to item 1, wherein the dielectric is formed from the ogara material. (Item 15) The capacitor according to item 14, wherein the ogara material is hemp ogara or kenaf ogara. (Item 16) The capacitor according to item 1, wherein the dielectric includes ogara or a derivative thereof. (Item 17) The capacitor according to item 1 has a mass of at most about 5 kg. (Item 18) The capacitor according to item 17 has a mass of at most about 2 kg. (Item 19) The capacitor according to item 1, having an energy density of at least about 40 Watt-hours (Wh) / kg of effective mass over at least about 250 charge / discharge cycles through the electrical load at a temperature of 60°C to 100°C. (Item 20) The capacitor according to item 19, having an energy density of at least about 60 Wh / kg of effective mass over at least about 250 charge / discharge cycles through the electrical load at a temperature of 60°C to 100°C. (Item 21) The capacitor according to item 1, wherein the leather and / or sawdust material is leather and / or sawdust fibers or leather and / or sawdust powder. (Item 22) A method for storing electrical energy, comprising: (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, the dielectric being formed of leather fibers, leather powder, or a derivative thereof, and (iii) a second electrode adjacent to the dielectric, the second electrode being formed of a material capable of conducting to or from the electrical load and being electrically isolated from the first electrode, the capacitor having a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass over at least about 250 charge / discharge cycles at a temperature of 60°C to 100°C; (b) electrically connecting the capacitor to the electrical load; (c) charging or discharging the capacitor through the electrical load. A method comprising the above steps. (Item 23) 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 to 100°C, according to the method described in item 22. (Item 24) 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 to 100°C, according to the method described in item 23. (Item 25) 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 to 100°C, according to the method described in item 22. (Item 26) 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 to 100°C, according to the method described in item 25. (Item 27) 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 to 100°C, according to the method described in item 26. (Item 28) The electrical load is a power transmission network, according to the method described in item 22. (Item 29) The electrical load includes the electrical circuit of a vehicle, according to the method described in item 22. (Item 30) The electrical load includes the electrical circuit of an aircraft, according to the method described in item 22. (Item 31) The electrical load includes the electrical circuit of a train, according to the method described in item 22. (Item 32) The electrical load includes the electrical circuit of a ship, according to the method described in item 22. (Item 33) The dielectric is formed from tough skin fibers, according to the method described in item 22. (Item 34) The method according to item 33, wherein the bast fiber is a hemp bast fiber. (Item 35) The method according to item 22, wherein the dielectric is formed from bast powder. (Item 36) The method according to item 35, wherein the bast powder is hemp bast powder or kenaf bast powder. (Item 37) The method according to item 22, wherein the dielectric contains sawdust or a derivative thereof. (Item 38) The method according to item 22, wherein the capacitor has a mass of at most about 5 kg. (Item 39) The method according to item 38, wherein the capacitor has a mass of at most about 2 kg. (Item 40) The method according to item 22, wherein the capacitor has an energy density of at least about 40 Wh / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60 °C to 100 °C. (Item 41) The method according to item 40, wherein the capacitor has an energy density of at least about 60 Wh / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60 °C to 100 °C. (Item 42) A capacitor for storing electrical energy, a first electrode, wherein the first electrode is 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 an electrical conductivity lower than that of the material of the first electrode, 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 the second electrode is electrically isolated from the first electrode, comprising At least one of the first electrode, the second electrode, or both the first electrode and the second electrode is formed from a tough skin and / or an ogara material, The capacitor has a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C. (Item 43) The capacitor according to Item 42, having 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 to 100°C. (Item 44) The capacitor according to Item 43, having 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 to 100°C. (Item 45) The capacitor according to Item 42, having 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 to 100°C. (Item 46) The capacitor according to Item 45, having 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 to 100°C. (Item 47) The capacitor according to Item 46, having 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 to 100°C. (Item 48) The capacitor according to Item 42, wherein the electrical load is a power transmission network. (Item 49) The capacitor according to Item 42, wherein the electrical load includes an electrical circuit of a vehicle. (Item 50) The electrical load is the capacitor according to item 42, including the electrical circuit of an airplane. (Item 51) The electrical load is the capacitor according to item 42, including the electrical circuit of a train. (Item 52) The electrical load is the capacitor according to item 42, including the electrical circuit of a ship. (Item 53) The first electrode is the capacitor according to item 42, formed from bast fiber. (Item 54) The bast fiber is hemp bast fiber in the capacitor according to item 53. (Item 55) The first electrode is the capacitor according to item 42, formed from bast powder. (Item 56) The bast powder is hemp bast powder or kenaf bast powder in the capacitor according to item 55. (Item 57) The first electrode is the capacitor according to item 42, including ogara or its derivatives. (Item 58) The capacitor is the capacitor according to item 42, having a mass of at most about 5 kg. (Item 59) The capacitor is the capacitor according to item 58, having a mass of at most about 2 kg. (Item 60) The capacitor is the capacitor according to item 42, having an energy density of at least about 40 Wh / kg effective mass over at least about 250 charge / discharge cycles through the electrical load at a temperature of 60 °C to 100 °C. (Item 61) The capacitor is the capacitor according to item 60, having an energy density of at least about 60 Wh / kg effective mass over at least about 250 charge / discharge cycles through the electrical load at a temperature of 60 °C to 100 °C. (Item 62) A method for storing electrical energy, comprising: (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, the dielectric being formed of a material having an electrical conductivity lower than that of the material of the first electrode, and (iii) a second electrode adjacent to the dielectric, the second electrode being formed of a material capable of conducting electrons to or from the electrical load and being 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 tough fiber, tough powder, or a derivative thereof, and the capacitor has a power density of at least about 55 kilowatts (kW) per kilogram (kg) of effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C; (b) electrically connecting the capacitor to the electrical load; (c) charging or discharging the capacitor via the electrical load. A method comprising the above steps. (Item 63) The method according to Item 62, wherein 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 to 100°C. (Item 64) The method according to Item 63, wherein 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 to 100°C. (Item 65) The method according to Item 62, wherein 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 to 100°C. (Item 66) The method according to item 65, wherein 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 to 100°C. (Item 67) The method according to item 66, wherein 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 to 100°C. (Item 68) The method according to item 62, wherein the electrical load is a power transmission network. (Item 69) The method according to item 62, wherein the electrical load includes an electrical circuit of a vehicle. (Item 70) The method according to item 62, wherein the electrical load includes an electrical circuit of an airplane. (Item 71) The method according to item 62, wherein the electrical load includes an electrical circuit of a train. (Item 72) The method according to item 62, wherein the electrical load includes an electrical circuit of a ship. (Item 73) The method according to item 62, wherein the first electrode is formed from bast fiber. (Item 74) The method according to item 73, wherein the bast fiber is hemp bast fiber. (Item 75) The method according to item 62, wherein the first electrode is formed from bast powder. (Item 76) The method according to item 75, wherein the bast powder is hemp bast powder or kenaf bast powder. (Item 77) The method according to item 62, wherein the first electrode includes ogara or a derivative thereof. (Item 78) The method according to item 62, wherein the capacitor has a mass of at most about 5 kg. (Item 79) The capacitor has a mass of up to about 2 kg, according to the method described in item 78. (Item 80) The capacitor has an energy density of at least about 40 watt-hours (W h) / kg of effective mass over at least about 500 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C, according to the method described in item 62. (Item 81) The capacitor has an energy density of at least about 60 watt-hours (W h) / kg of effective mass over at least about 500 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C, according to the method described in item 80. (Item 82) A method of manufacturing a capacitor, (a) obtaining bast and / or shavings material derived from a plant; (b) treating the bast and / or shavings material to a treated material, the treated material being in the form of fibers or particles; (c) using the treated material to produce a first electrode, a second electrode, and / or a dielectric; (d) assembling the first electrode, the second electrode, and the dielectric to produce a capacitor, the capacitor comprising: (i) the first electrode; (ii) a dielectric adjacent to the first electrode; and (iii) a second electrode adjacent to the dielectric, the second electrode being electrically isolated from the first electrode, the capacitor having a power density of at least about 55 kilowatts (kW) / kilogram (kg) of effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C; comprising a method. (Item 83) The plant is cannabis, according to the method described in item 82. (Item 84) The treatment includes grinding the bast and / or shavings material to form particles containing the bast and / or shavings material, according to the method described in item 82. (Item 85) The method according to item 82, wherein the leather and / or sawdust material contains leather and / or sawdust fibers. (Item 86) The method according to item 82, wherein the leather and / or sawdust material is a leather material. (Item 87) The method according to item 82, wherein the leather and / or sawdust material is a sawdust material. (Item 88) The method according to item 82, further comprising weaving the capacitor into the fabric. (Item 89) The capacitor according to item 82, having a power density of at least about 75 kW / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C to 100°C. (Item 90) The capacitor according to item 89, having a power density of at least about 100 kW / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at the temperature of 60°C to 100°C. (Item 91) The capacitor according to item 90, having a power density of at least about 55 kW / kg effective mass over at least about 500 charge / discharge cycles via the electrical load at the temperature of 60°C to 100°C. (Item 92) The capacitor according to item 91, having a power density of at least about 55 kW / kg effective mass over at least about 1000 charge / discharge cycles via the electrical load at the temperature of 60°C to 100°C. (Item 93) The capacitor according to item 92, having a power density of at least about 55 kW / kg effective mass over at least about 2000 charge / discharge cycles via the electrical load at the temperature of 60°C to 100°C. (Item 94) The electrical load is the capacitor according to item 82, which is a power transmission network. (Item 95) The electrical load is the capacitor according to item 82, which includes the electrical circuit of a vehicle. (Item 96) The capacitor is the capacitor according to item 82, which has a mass of at most about 5 kg. (Item 97) The capacitor is the capacitor according to item 96, which has a mass of at most about 2 kg. (Item 98) The capacitor is the capacitor according to item 82, which has an energy density of at least about 40 Wh / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C. (Item 99) The capacitor is the capacitor according to item 98, which has an energy density of at least about 60 Wh / kg effective mass over at least about 250 charge / discharge cycles via the electrical load at a temperature of 60°C to 100°C.

[0029] Additional aspects and advantages of the present disclosure will be readily apparent to those skilled in the art from the following detailed description, which shows and describes only illustrative embodiments of the present disclosure. As will be recognized, the present disclosure is capable of other different embodiments and some of its details are capable of modification in various obvious respects without departing from the present disclosure. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive. Citation by reference

[0030] All publications, patents, and patent applications described herein are hereby incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. To the extent that any incorporated publications and patents or patent applications conflict with the present disclosure contained herein, the present specification is intended to supersede and / or prevail over any such conflicting materials.

Brief Description of the Drawings

[0031] The novel features of the invention are set forth with particularity in the appended claims. A further understanding of the features and advantages of the present invention will be obtained from the following detailed description, which describes illustrative embodiments in which the principles of the invention are utilized, and from the accompanying drawings (also referred to herein as "figures" (Figure and FIG.)).

[0032]

Figure 1

[0033]

Figure 2

[0034]

Figure 3

Modes for Carrying Out the Invention

[0035] Although various embodiments of the present invention are shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, modifications, and substitutions can be contemplated by those skilled in the art without departing from the present invention. It should be understood that various alternatives to the embodiments of the present invention described herein may be employed.

[0036] As used herein, the term "bast fiber" generally refers to natural (e.g., plant) fibers and / or other materials collected from the phloem (the "inner bark," sometimes called the "skin") or bast that surrounds the trunk of certain dicotyledonous plants. Such plants may include, for example, hemp plants. Bast fibers may be obtained from herbs cultivated in agriculture, such as flax, hemp, jute, sisal, kenaf, or ramie. Bast fibers may be obtained from wild plants such as trees like nettles and paulownia, linden, wisteria, or mulberry. Bast fibers may be obtained from such natural materials, for example, through 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 adhesive (pectinase) substances from the bast fibers and enable their isolation. In certain cases, bast fibers may be obtained through peeling or manual or mechanical stripping from the plant. In some cases, after extraction of the bast fibers (e.g., through stripping), the stems, trunks, or cores of the plant such as shives or fragments may be obtained.

[0037] As used herein, the term "bast powder" generally refers to powdered bast fibers and / or powder from the phloem or bast that surrounds the trunk of certain dicotyledonous plants. In some cases, the bast powder can contain particles within the nanometer or micrometer range. The particles may be cellulose particles such as microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) derived from the bast or bast fibers. In some cases, MCC and NCC may be isolated and / or derived from the bast or bast fibers through acid hydrolysis (e.g., hydrochloric acid hydrolysis). The bast powder may contain nanoparticles and / or microparticles. The bast powder can be hemp bast powder, kenaf bast powder, sisal bast powder, and / or jute bast powder.

[0038] As used herein, the term "bast fiber" or "fragment fiber" generally refers to natural (e.g., plant) fibers and / or other materials collected from the stems, trunks, or cores of certain dicotyledonous plants. Such plants may include, for example, hemp plants. Bast fibers may be obtained from herbs cultivated in agriculture, such as flax, hemp, jute, sisal, kenaf, or true hemp. Bast fibers may be obtained from wild plants such as nettles and elm, linden, wisteria, or mulberry trees. Bast fibers may be obtained from such natural materials, for example, through retting or otherwise extracting the bast from the inner xylem or epidermis (e.g., bark surface) of the plant and recovering the inner stem, trunk, or core of the plant. In certain cases, bast fibers may be obtained through peeling or manual or mechanical stripping of the bast from the plant. In some cases, after extraction of the bast fibers (e.g., through stripping), the stems, trunks, or cores of the plants such as bast or fragments may be obtained.

[0039] As used herein, the term "bast powder" generally refers to powdered bast fibers and / or powder from the trunks, stems, or cores of certain dicotyledonous plants. In some cases, the bast powder can include particles in the nanometer or micrometer range. The particles may be cellulose particles derived from bast or bast fibers. The bast powder may include nanoparticles and / or microparticles.

[0040] A capacitor is a type of energy storage system that can have a higher power density and thus can release energy over a shorter time period than some alternative energy storage systems (e.g., batteries). A supercapacitor, also known as an electric double layer capacitor, an electrochemical capacitor, or an ultracapacitor, can be configured to still have a high power density while storing an amount of charge (and thus electrical energy) that is several orders of magnitude greater than that stored by a normal capacitor. Capacitors have a variety of uses and can be configured to power electrical applications that require short but powerful bursts of energy (e.g., engine starting, rapid acceleration, signal stabilization, etc.).

[0041] A capacitor may comprise two electrodes separated from each other by a separating material. The separating material can be a dielectric or, in the case of a supercapacitor, a separator immersed in an electrolyte. The performance of a capacitor and / or supercapacitor can be significantly improved or decreased depending on the individual materials selected for the individual components of the capacitor, such as the electrode material and the dielectric material.

[0042] Provided is a capacitor that at least partially comprises a natural derivative. In some cases, the natural derivative may be a bast fiber, bast powder, or a derivative thereof. In some cases, the natural derivative may include a derivative or plant from the stem, trunk, and / or core of a herb or plant (e.g., flax, hemp, jute, sisal, kenaf, or true hemp). For example, the derivative may include shives, shive fibers, shive powder, fragments, fragment fibers, or fragment powder from hemp or flax. For example, the dielectric of the capacitor can be formed from a bast fiber, bast powder, hemp shives, or a derivative thereof. In another embodiment, one or both electrodes of the capacitor can be formed from a bast fiber, bast powder, hemp shives, or a derivative thereof. Such a capacitor can be configured to have various power densities and various energy densities within a defined operating temperature range. The capacitor can be capable of withstanding repeated charge / discharge cycles within a defined operating temperature range. The capacitor of the present disclosure may be a supercapacitor.

[0043] The capacitors of the present disclosure can enable substantially high energy density (e.g., at least about 40, 50, or 60 Wh / kg) and substantially high power density (e.g., at least about 20, 40, or 60 kW / kg). These capacitors may have various uses, such as continuous or intermittent supply of energy within a building, vehicle (e.g., car, truck, train, jet), or electronic device. The capacitor may be portable.

[0044] Now, refer to the figures. It should be understood that the figures and features therein are not necessarily drawn to an exact scale.

[0045] Figure 1 shows a schematic diagram of a capacitor. Such a capacitor may be a supercapacitor. A capacitor can store electrical energy by enabling the accumulation of an electric potential 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 with lower conductivity than either of the two electrodes. Each of the two electrodes 104, 108 can be capable of conducting electrons.

[0046] A single dielectric 106 is shown, but the capacitor may include a plurality of dielectrics such as at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, or more. The dielectrics may be arranged adjacent to each other as separate layers. The dielectrics may have a uniform profile or a non-uniform profile. For example, the dielectrics may have a substantially flat boundary or a curved boundary. The dielectrics may include the same material or different materials.

[0047] The first electrode 104 can include a first conductive material that is in electrical communication with a circuit 114 via a first terminal 115. The first terminal 115 can be a separate conductive component (e.g., a metal plate) from the first conductive material 104 or can be a connection point of the first electrode 104 to and / or from the circuit 114. The second electrode 108 can include a second conductive material that is in electrical communication with a common circuit 114 via a second terminal 116. The second terminal 116 can be a separate conductive component from the second conductive material 108 or can be a connection point of the second conductive material 108 to and / or from the circuit 114.

[0048] In some instances, each of the electrodes 104, 108 can comprise one or more adjacent layers of a conductive material. In some instances, the dielectric 106 can comprise one or more adjacent layers of an insulating material (e.g., glass, air, ceramic, etc.). The first electrode 104 and the second electrode 108 can include the same material or different materials.

[0049] The capacitance of a capacitor can depend on various factors, among other factors, including, inter alia, the distance between the two electrodes 104, 108, the surface area of the individual conductive electrodes, and the dielectric constant of the dielectric. For example, the capacitance can increase as the distance between the two electrodes decreases and / or as the surface area of the individual conductive electrodes increases.

[0050] The capacitor can be charged or discharged by applying an electrical load 112 to the capacitor. For example, the capacitor can be charged 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 flow of current can be interrupted by the non-conductive dielectric, and as a result, opposite charges can accumulate on the two electrodes of the capacitor. A potential can be created across the dielectric between the two electrodes and subsequently stored. In another embodiment, the capacitor can be discharged by electrically coupling an electrical load 112 that consumes power to the capacitor. The potential on the electrodes can be discharged via the electrical load 112.

[0051] A supercapacitor, also known as an electric double layer capacitor, an electrochemical capacitor, or an ultracapacitor, can be configured to store an amount of charge (and thereby electrical energy) that is several orders of magnitude greater than that stored by a conventional capacitor. The capacitors of the present disclosure can store 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 10,000 times more charge than a typical capacitor. A supercapacitor can store electrical energy by allowing a potential to build up across a dielectric 106 or dielectric equivalent between two conductive electrodes 104, 108, with the two conductive electrodes 104, 108 being isolated from each other by a dielectric 106 positioned therebetween.

[0052] The dielectric 106 can comprise 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 form on both sides of the dielectric separator between the dielectric separator and each electrode via ion migration through the electrolyte. Unlike in a battery, the electrodes do not chemically react with the electrolyte. As a result, two pairs of opposite charge layers can store the potential.

[0053] 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 in electrical communication with the circuit 114 via the first terminal 115. The first terminal 115 can be a conductive component separate from the first conductive material or can be the connection point of the first electrode 104 to and / or from the circuit 114. For example, the first conductive material can be formed from a porous conductive material (such as activated carbon, graphene, carbon nanotubes, carbon black, etc.) that communicates with the circuit 114 via the first terminal 115. The porous conductive material advantageously increases the actual surface area of the electrode, stores charge (such as ions), thereby increasing the capacitance of the capacitor (such as a supercapacitor). Similarly, the second electrode 108 of the supercapacitor can include a second conductive material that is in electrical communication with the common circuit 114 via the second terminal 116. The second terminal 116 can be a conductive component separate from the second conductive material or can be the connection point of the second electrode 108 to and / or from the circuit 114. For example, the second conductive material can also be formed from a porous conductive material that communicates with the circuit 114 via the second terminal 116.

[0054] Different materials can be selected to form the electrodes and / or dielectrics of the capacitor to vary the performance capabilities of the capacitor such as power density and energy density. In some cases, the desired performance capabilities must be considered in comparison to other considerations such as the operable temperature range, thermal stability (such as flammability), structural stability, durability, toxicity, environmental impact, dimensional limitations (such as size, weight, etc.), manufacturing economy, and / or combinations thereof.

[0055] In some cases, different materials paired within a capacitor, such as using a first electrolyte composition (e.g., a first salt and a first solvent, etc.) in combination with an electrode made from a second material (e.g., activated carbon), can produce different results. For example, a larger electrode surface area can generally increase the capacitance. However, when the electrode has a porous structure, the transport ability 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, ions in a particular electrolyte composition may be too small or too large to effectively interface with the surface of the porous structure.

[0056] Materials with a relatively optimal structure for use as capacitor electrodes, such as graphene (e.g., activated graphene, curved graphene, laser scribed graphene, ultrathin planar graphene, sponge-like graphene, etc.) or other carbon micro or nano materials with large and flat adsorption surfaces and high in-plane electrical conductivity, can be expensive to manufacture compared to other alternatives. For example, graphene-like materials can be synthesized using relatively costly methods such as exfoliation (e.g., modified Hummers method), chemical vapor deposition, or microwave synthesis. In contrast, carbon derived from petroleum or bio-waste can be synthesized through pyrolysis or hydrothermal methods.

[0057] In some cases, biomass such as leather fiber material, leather 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 of 1 nanometer to a maximum of 1000 nanometers or 500 nanometers), using conventional processes such as hydrothermal synthesis. Such precursors may be formed, for example, in the form of sheets, tubes, or rolls. Leather fiber, leather powder, hemp shive, or derivatives thereof can be active materials for one or more components (e.g., electrodes) of the capacitor.

[0058] For example, the bast fiber and / or the bamboo fiber can first undergo hydrothermal carbonization to break down the initial thread-like structure of the fiber into smaller fragments. The hydrothermal synthesis process can result in a high oxygen content (e.g., oxygen-containing functional groups), making the product susceptible to a subsequent activation process using an activating reagent such as potassium hydroxide (KOH). After the hydrothermal process, the fiber can then be activated with KOH, for example, to penetrate the fiber and produce 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 bast fiber and / or the bamboo fiber may or may not be pre-treated, such as to reduce the size or expand the fiber structure.

[0059] The hydrothermal carbonization process can produce 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 greater. 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 less. 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 greater. 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 less. Alternatively, or in addition thereto, hydrothermal carbonization of the bast fiber, bast powder, sawdust fiber, or sawdust powder material can produce at least one stack of carbon nanosheets.

[0060] At least one stack of graphene flakes or carbon nanosheets from the hydrothermal carbonization process may be processed using one or more exfoliation techniques to produce at least one carbon nanosheet having a thickness of one carbon atom. The exfoliation techniques can have high scalability, reproducibility, processability, and / or low production costs. The one or more exfoliation techniques may utilize a liquid-phase exfoliation (LPE) device based on fluid dynamics. 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 fluid dynamics to disperse at least one stack of graphene flakes or carbon nanosheets in one of the suitable solvents or a mixture thereof under intensive shear forces. The intensive shear forces can be sufficient to exfoliate or delaminate at least one carbon nanosheet from at least one stack of carbon nanosheets. The LPE device that utilizes fluid dynamics can be a vortex fluid device, a pressure-driven fluid dynamics device, or a rotary mixer-driven fluid dynamics 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 a speed of about 10,000 r.p.m., 1,000 r.p.m., 100 r.p.m., 10 r.p.m., or less than that. The pressure of the pressure-driven fluid dynamics 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 a pressure of 100 MPa, 50 MPa, 40 MPa, 30 MPa, 20 MPa, 10 MPa, 5 MPa, or lower. The rotor speed of the rotary mixer-driven fluid dynamics 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 may be about 10,000 r.p.m., 1,000 r.p.m., 100 r.p.m., 10 r.p.m., or less than or equal to a lower speed.

[0061] In another embodiment, the bast or bagasse powder can include micron-sized or nano-sized cellulose particles such as microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), or cellulose nanocrystals (CNC) derived from the bast or bagasse. The powder may include nanoparticles and / or microparticles. In some cases, MCC, NCC, and CNC may be isolated and / or derived from the bast or bagasse via acid hydrolysis (e.g., hydrochloric acid hydrolysis). For example, the bast or bagasse fibers, after recovery, can be dried to a moisture content of less than 10% (e.g., in an industrial oven), and then ground into a fine powder (e.g., via a cutting mill grinder), resulting in a bast or bagasse powder (e.g., hemp bast powder, kenaf bast powder, hemp bagasse powder, etc.). The powder can be subjected to an alkali treatment and washing. In some cases, the alkali treatment and washing can include treatment at 80 °C for about 2 hours using a 4% (w / w) sodium hydroxide (NaOH) solution, washing with distilled water, and filtration. The alkali treatment and washing can be repeated (e.g., 2 cycles, 3 cycles, 4 cycles, etc.). Following the alkali treatment and washing, a bleaching treatment can be carried out. In some cases, the bleaching treatment can include steps of immersing in a solution containing an equal amount of acetic acid buffer, 1.7% (w / w) aqueous chloride solution, and distilled water, washing with distilled water, and filtration. The bleaching treatment can be repeated (e.g., 2 cycles, 3 cycles, 4 cycles, etc.). The bast or bagasse can then be subjected to acid hydrolysis (e.g., hydrochloric acid hydrolysis, sulfuric acid hydrolysis, etc.). In some instances, the acid hydrolysis can include steps of exposing 4 - 6% (w / w) bleached fibers to preheated 65% sulfuric acid at 50 °C for 60 minutes, mixing the suspension (e.g., via a magnetic stirrer), separating via a centrifuge maintained at 4000 revolutions per minute (rpm) for 30 minutes, and dialyzing with distilled water. The whisker crystal suspension can be homogenized, resulting in bast or bagasse-derived nanocellulose whisker crystals.In another example, NCC or CNC (e.g., nanoparticles) can be prepared using cellulose isolated from bast or shives via acid hydrolysis (e.g., hydrochloric acid hydrolysis, sulfuric acid hydrolysis). Bast or shives-derived micro or nano powders can demonstrate properties such as high aspect ratio, high surface area, and high elasticity. In some cases, bast powder can contain particles within the nanometer or micrometer range. For example, bast or shives powder particles may 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, bast or shives powder particles may have a diameter of up to about 500, 450, 400, 350, 300, 250, 150, 100, 90, 80, 70, 60, 50 nm, or less. Alternatively, bast or shives powder particles may 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, bast or shives powder particles may have a diameter of up to about 500, 450, 400, 350, 300, 250, 150, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10 μm, or less.

[0062] In light of the above considerations, the capacitor may at least partially include bast fibers, bast powder, hemp shives (e.g., fibers, powders, etc.), or derivatives thereof. For example, one or both of the two electrodes may include bast fibers, bast powder, hemp shives, or derivatives thereof. In some cases, the bast fiber-based, bast powder-based, or hemp shive-based electrodes may include carbon nanosheets or carbon nanotubes that exhibit a high level of mesoporosity demonstrating favorable electrochemical properties in conventional ionic liquid electrolytes. Alternatively, or in addition, the dielectric or at least a portion of the dielectric may include bast fibers, bast powder, hemp shives, or derivatives thereof. For example, the double layer of NFC and CNC can be used as the dielectric within the supercapacitor. In some cases, the CNC and NFC dielectrics can be deposited on each electrode by spray coating a thin film of a CNC solution (e.g., 0.8 wt% in water), drying the CNC film (e.g., at 60 °C), drop casting an NFC gel (e.g., 0.8 wt% in water), and drying the gel (e.g., at room temperature) for dehydration. A mechanical mask (e.g., a polydimethylsiloxane (PDMS) mask) may be used during the deposition.

[0063] In some cases, the capacitor may at least partially include hemp (e.g., Cannabis sativa L.) bast fibers, hemp bast powder, hemp shives (fibers or powder), or derivatives thereof. Hemp fibers (e.g., bast fibers, shive fibers, etc.) may include one or more layers of cellulose, hemicellulose, and lignin. In particular, hemp fibers may include laminated microfibers composed of crystalline cellulose fibrils. During the hydrothermal process of hemp fibers (e.g., carried out at about 170 - 200 °C), among other reactions (e.g., hydrolysis, dehydration, decomposition, condensation of lignin, etc.), crystalline cellulose can be partially carbonized. The hydrothermal process can convert most of the hemicellulose and part of the lignin into soluble organic compounds while relaxing the interbonded layers of cellulose microfibers. Hemicellulose and lignin can be dissolved and isolate the relaxed cellulose microfibers.

[0064] During a subsequent activation process (e.g., carried out at about 700 - 800 °C), an activation reagent such as KOH, for example, can penetrate the relaxed microfiber layer, thereby separating the layer as a sheet. KOH can further carbonize and activate the separated layer, reduce its individual thickness, and generate microporosity and mesoporosity within the carbon sheet structure. In particular, the crystalline cellulose content of the hemp precursor enables the derivative formation from the KOH activation process to have a certain degree of order (e.g., graphite order) in its structural properties. Alternatively, a pyrolysis process can be used to synthesize bast or shive fiber derivatives.

[0065] The derivatives resulting from the hemp fibers can include carbon nanosheets with favorable microporosity, mesoporosity, and graphite alignment for use in a capacitor system. 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., the material of the first electrode 104 in FIG. 1), the second conductive material for the second electrode (e.g., the material of the second electrode 108 in FIG. 1), or the conductive material for both the first and second electrodes. A dielectric, electrolyte, and / or separator can be placed between the first and second electrodes to complete the capacitor. Alternatively, bast, ogara, or fragment fibers can be obtained from flax, true hemp, jute, kenaf, Chinese cork tree, linden, and / or other plants.

[0066] In other instances, the bast fiber, bast powder, bagasse, or derivatives thereof can be used as a dielectric material (e.g., dielectric 106 in FIG. 1). For example, the cellulose fibers or powder in the bast or bagasse (e.g., fiber or powder) can have a relatively high dielectric constant, which can be advantageous for capacitor performance. In some instances, natural fibers or powders (e.g., bast fibers, bast powders, bagasse fibers, bagasse powders, etc.) are mixed with synthetic fibers or powders in variable ratios to vary the electrical resistance and / or dielectric constant. In some instances, the moisture content (e.g., humidity) is modified to vary the electrical resistance and / or dielectric constant of the bast or bagasse material. For example, the bast or bagasse material can have a moisture content of at least about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more. Alternatively, the bast or bagasse material can have a moisture content of less than or equal to about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, or less.

[0067] In some cases, the operating temperature can be varied to vary the electrical resistance and / or the electrical permittivity. For example, the operating temperature can be up to 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 less. In some cases, the tough skin material can be configured to exhibit performance with variable electrical resistance and / or electrical permittivity over a certain humidity range and / or operating temperature range. In some cases, the thickness, surface mass, density (e.g., number of threads / unit length), and / or other configurations (e.g., warp and weft) of the wavy structure within the cellulose fibers within the tough skin or ogara fibers can be modified to vary the electrical resistance and / or the electrical permittivity.

[0068] In some cases, such tough skin or ogara materials (e.g., pure hemp) or derivatives thereof (e.g., graphene-like carbon nanosheets, tough skin fiber-reinforced polymer composites, CNC, NCC, etc.) can be used as dielectric materials (e.g., dielectric 106 in FIG. 1). For example, a polymer (e.g., pure polypropylene, pure unsaturated polyester material, etc.) can be reinforced with one or more tough skin or ogara fibers or powders (e.g., hemp, jute, etc.) to form a hybrid fiber or powder composite material having a higher dielectric constant (e.g., permittivity). The first electrode and the second electrode each have a higher electrical conductivity than the dielectric and can each be disposed adjacent to the dielectric, and the first and second electrodes are electrically isolated from each other.

[0069] In some cases, the elastomeric material, the wood pulp material, or its 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. Through electrospinning, carbon fibers with a diameter of less than 1 micrometer (micron) can be formed with relatively high control.

[0070] The electrospinning setup can include a polymer solution, a high-voltage power source, a needle (e.g., a spinneret, nozzle, etc.), and an electrode collector. The high-voltage power source can be any applied unit configured to generate a strong electric field. The polymer solution can exit the container through the needle. The electrode collector may be disposed at a distance from the tip of the needle. The polymer solution and the electrode collector can be subjected to the strong electric field applied by, for example, the high-voltage power source. The droplets of the polymer solution can exit the needle. When the electric force within the electric field overcomes the surface tension of the polymer solution droplets, the droplets can be elongated in a substantially whip-like trajectory to form a solution jet or a focused fluid stream. Under the direction of the strong electric field, the solution jet can be bent or whipped and stretched thinner. Subsequently, solvent evaporation from the jet can result in dry or semi-dry fibers that can randomly deposit on the electrode collector to form a nanofiber web. The electrospun fiber diameter can be on the order of about 1 micron to about 10 nanometers. The resulting small fiber diameter and large aspect ratio of the fibers can lead to a significantly high surface / volume ratio.

[0071] In some cases, the droplets can be subjected to a high-speed circumferentially uniform air flow in addition to a strong electric field, as in a gas-assisted electrospinning (GAES) system. The GAES system can provide much higher throughput of fibers, thinner fibers, and improved extensibility of the fluid jet, and better control of directing the fibers towards the collector with, for example, low electrical interference between adjacent or neighboring nozzles.

[0072] The input polymer solution can include a well-dispersed amount of fibers (e.g., bast, ogara, etc.) or derivatives thereof such as graphene, carbon nanosheets, carbon nanotubes, graphene nanoribbons, and other carbon nanofiber composites. In some cases, the polymer / dispersion solution can be prepared by separately preparing the polymer solution and the dispersion solution and mixing them together. The polymer / dispersion solution can be a homogeneous solution. Electrospinning the polymer / dispersion solution can produce resulting nanocomposite fibers having well-dispersed embedded nanostructures. For example, a carbon nanotube (CNT) / polymer composite subjected to electrospinning can result in better-aligned nanocomposite fibers in which the CNTs are oriented substantially parallel to the nanofiber axis. In some cases, stable dispersion of the CNTs can be achieved by using surfactants (e.g., sodium lauryl sulfate), 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 can be facilitated via sonication of the solution.

[0073] Advantageously, the electrospun fibrous polymer composites (e.g., CNT / polymer composites) can demonstrate significantly improved mechanical and electrical properties suitable for use in the capacitors and / or supercapacitors described herein. The improved dispersion and orientation of nanotubes within the polymer fibers and the strong interfacial adhesion resulting from nanotube surface modification can significantly improve the tensile strength and Young's modulus of the polymer. The fiber / polymer composites can also have improved resistance to mechanical strain (e.g., crushing strain) due to nanopores on the fiber surface that shield slippage and stress and highly aligned nanotubes along the fiber axis that receive mechanical loading from the polymer matrix. Further, the presence of conductive natural fibers (e.g., bast fibers, wood pulp fibers, etc.) or fiber derivatives within the fiber / polymer composites can provide a way for relatively low-conductive polymers to improve their conductivity for various applications.

[0074] The nanofiber natural fiber / polymer composites can be used as materials for electrodes and / or dielectrics, etc. in capacitors or supercapacitors as described herein.

[0075] In some cases, the electrodes, dielectrics, and / or all of the capacitors may be produced and / or assembled via three-dimensional (3D) printing, where the input and / or output materials are bast or wood pulp materials (e.g., hemp, flax, etc.) fibers or powders. The 3D printing can be 3D nanoscale printing. For example, the individual components of the capacitor may be printed layer by layer on a desired location (e.g., panel, wing, fabric, etc.) with high modularity and flexibility.

[0076] A capacitor that at least partially includes a leather fiber, leather powder, sawdust fiber, sawdust powder, or a derivative thereof can have a mass of up to 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 needs of a particular type of electrical load (such as a power grid, smart grid, or the electrical circuit of a vehicle, gas vehicle, electric vehicle, airplane, jet, train, rail vehicle, ship, motor ship, electronic device, renewable energy recovery and / or storage system, etc.) that is electrically coupled to the capacitor.

[0077] Figure 2 illustrates a method of storing electrical energy using a natural fiber or powder capacitor. In a first operation 201, a capacitor including bast fiber, bast powder, sawdust, or a derivative thereof is activated. The capacitor can include at least partially bast fiber, bast powder, sawdust, or a derivative thereof. In some cases, the first electrode, the second electrode, or both the first and second electrodes of the capacitor can include bast fiber, bast powder, sawdust, or a derivative thereof. In other cases, the dielectric of the capacitor can include bast fiber, bast powder, sawdust, or a derivative thereof. In still other cases, both the dielectric and one or both of the electrodes of the capacitor can include bast fiber, bast powder, sawdust, or a derivative thereof. For example, the capacitor can consist entirely of a bast material (e.g., fiber, powder), a bast derivative, a sawdust material (e.g., fiber, powder), or a sawdust derivative product. In certain cases, one or both of the electrodes can include a bast or sawdust derivative (e.g., a graphene-like derivative of hemp bast or sawdust fiber), and the dielectric can include a pure bast or sawdust material (e.g., pure hemp fiber) or a mixture of bast or sawdust materials (e.g., with or without synthetic fibers, powders, etc.).

[0078] The first and second electrodes can be electrically isolated from each other such that electrons are not directly conducted to or from the two electrodes. The dielectric can be disposed adjacent to each of the first and second electrodes and between the two electrodes. In some cases, with respect to a supercapacitor, the dielectric can comprise an electrolyte and / or a separator immersed in the electrolyte. The first and second electrodes can each be configured to contact the electrolyte and not chemically react with the electrolyte. For example, a plurality of ions present in the electrolyte can concentrate on the electrode-electrolyte interface.

[0079] Once the capacitor is activated in the following 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 and the terminals of the second electrode and the electrical load and / or the power source can be electrically connected in the same circuit (e.g., via a conductive wire). In the following 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 an alternative energy storage system (e.g., a battery) or a power supply source. In other cases, the capacitor can be electrically connected to an electrical load that consumes power and discharges the capacitor.

[0080] FIG. 3 shows a schematic diagram of a capacitor 304 in electrical communication with an electrical load 302. In some instances, a first electronic component (e.g., a capacitor, an electrical load, etc.) can be in electrical communication with a second electronic component when the first and second electronic components are components of the same electrical circuit. The electrical load 302 can be a power grid or a vehicle, airplane, jet, train, railroad car, ship, electronic device, electrical circuit of a smart grid, or another device capable of consuming or generating power. Examples of vehicles include gasoline vehicles, electric vehicles, hybrid gas / electric vehicles, motor ships, or other electric or non-electric vehicles. The electronic device can be a personal computer (e.g., a portable PC, a desktop PC, etc.), a slate or tablet PC (e.g., an Apple® iPad®, a Samsung® Galaxy Tab, etc.), a phone, a smartphone (e.g., an Apple® iPhone®, an Android-compatible device, a Blackberry®), or a personal digital assistant. As an example, the capacitor 304 can be used to power an electrical load that requires a short but powerful burst of power, such as starting an engine, braking, and / or providing acceleration at the wheels of a vehicle or other transport unit (e.g., an airplane). For example, an airplane in electrical communication with the capacitor 304 can receive a sufficient burst of power to accelerate its wheels during takeoff and / or in the vicinity thereof, such as to shorten the runway length required for takeoff.

[0081] Capacitor 304 can be used to power various high - processing and computing systems. For example, computing systems applied to any high - load processing tasks such as blockchain mining systems (e.g., for cryptocurrency tokens, etc.), artificial intelligence systems, quantum systems, machine learning systems, encryption systems (including any decoding methods), network operating systems, high - definition graphic systems, or other large - scale systems may be powered by the capacitor of the present disclosure. Alternatively, or in addition, the capacitor may be used to significantly cool the above - mentioned systems and prevent overheating.

[0082] Capacitor 304 can be used to power various horizontal take - off and landing (HOTOL) or vertical take - off and landing (VTOL) aircraft systems. For example, rotors, prop - rotors, and propellers used for take - off, flight, or landing may be powered by the capacitor of the present disclosure. The rotors, prop - rotors, or propellers may be electric or hybrid gas / electric. The HOTOL aircraft system may be a distributed electric propulsion system. The VTOL aircraft system may be an unmanned aerial vehicle (UAV) such as a drone. The UAV may be flown remotely by a pilot at a remote location using radio frequencies or may fly autonomously according to a pre - programmed flight. The aircraft system powered by capacitor 304 may be used as a transportation system for carrying at least one passenger, one piece of luggage, or both.

[0083] The capacitor 304 can be incorporated into a wearable fabric that can be worn as a wearable energy storage device. In some cases, leather or hemp material or derivatives thereof (e.g., carbon nanosheets) can be integrated as part of the dielectric material into a two-dimensional supercapacitor with a high aspect ratio (e.g., wires, threads, etc.). The two-dimensional supercapacitor may be flexible. The two-dimensional supercapacitor can be woven into a wearable fabric as a wearable energy storage device and power and / or charge various computing systems or electronic devices. The wearable fabric may include gloves, socks, shirts, ties, belts, and military vests. Various computing systems or electrical devices may be part of a wearable fabric (e.g., temperature sensors, heaters, light-emitting diode displays, heart rate monitors, fitness trackers, etc.) or a separate portable device (e.g., mobile devices, smartwatches, smart glasses, fitness trackers, etc.). The two-dimensional supercapacitor may be a microsupercapacitor having a cross-sectional dimension of at least 0.1, 1, 10, 100, 1000 micrometers or more. The two-dimensional supercapacitor may be, but is not limited to, a hierarchically structured composition of a conductive material and a leather or derivative thereof. The hierarchically structured composition may be a layer-by-layer (LBL) assembly. In one embodiment, a two-layer film including a conductive layer including at least one conductive polymer and a dielectric layer including at least leather and / or hemp material or derivatives thereof may be wound around a two-dimensional supercapacitor yarn. An actuator may be used to wind the two-layer film around the two-dimensional supercapacitor yarn. The dielectric layer may include mast fibers aligned along the length of the two-dimensional supercapacitor yarn. The dielectric layer may further include a liquid or solid electrolyte and / or a separator. The dielectric layer may contain a preferred degree of air with microporosity and / or mesoporosity as a separator. The two-dimensional supercapacitor yarn may constitute a plurality of LBL assemblies of the conductive layer and the dielectric layer.The two-dimensional supercapacitor thread may have at least about 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, or more LBL assemblies of conductive layers and dielectric layers.

[0084] In some cases, the capacitor 304 can be integrated as part of a power grid or smart grid for an area the size of a city or multiple cities. In some cases, the electrical load 302 can be, but is not limited to, an alternative and / or renewable energy recovery or storage system such as a solar power generation, wind power generation, hydro power generation, geothermal power generation, and gravity-assisted power generation system. In some cases, the capacitor 304 may act as a power buffer for an energy recovery or storage system.

[0085] In some cases, the same electrical load (e.g., a vehicle, an energy recovery or storage system, etc.) can both charge and discharge the capacitor for different uses of the electrical load, etc. In some cases, a first electrical load can charge the capacitor and a second electrical load can discharge the capacitor. A circuit comprising the capacitor 304 and the electrical load 302 may comprise other electrical components (e.g., switches, transistors, regulators, etc.) and can facilitate electrical communication between the capacitor 304 and the electrical load 302. In some cases, the capacitor 304 can be in electrical communication with multiple electrical loads. In some cases, the electrical load 302 can be in electrical communication with multiple capacitors 304, which are connected continuously in series, continuously in parallel, and / or discontinuously. In some cases, a circuit may comprise multiple capacitors and multiple electrical loads. In some cases, a circuit may comprise multiple power sources (e.g., fuel cells, batteries, other capacitors, etc.) including the capacitor 304. The circuit architecture for any of the circuits described above or further below is not limited to that shown in the schematic diagram of FIG. 3.

[0086] A capacitor containing a leather fiber, leather powder, sawdust, or a derivative thereof can be capable of charging or discharging electricity at 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 a higher temperature. Alternatively, the capacitor can be capable of charging or discharging electricity at a temperature 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 less than that temperature. In some cases, the capacitor can be capable of charging or discharging electricity in a temperature range such as about 60 - 100 °C. For example, below a certain temperature, the charge and / or discharge rate can be limited. For example, above a certain temperature, the capacitor can become unstable (e.g., due to the thermal stability and flammability of the electrode material and / or dielectric material). In some cases, the capacitor can have better performance (e.g., higher power density, higher energy density, etc.) in a certain temperature range (e.g., 60 - 100 °C) than another temperature range.

[0087] In some cases, over a temperature range of about 60 to 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. A relatively higher power density can enable the capacitor to recharge and / or supply a certain amount of electrical energy in a relatively shorter time period. 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.

[0088] In some cases, over a temperature range of about 60 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. A relatively higher energy density can enable the capacitor to store a relatively higher amount of energy at 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 over 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.

[0089] In some cases, over a temperature range of about 60 to 100 °C, the capacitor can be configured to 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 while enduring at least about 250 charge / discharge cycles. The more charge / discharge cycles the capacitor can endure, the longer the capacitor can remain in the circuit without the need for 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 over 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 over 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 over 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.

[0090] In some cases, over a temperature range of about 60 to 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, or less. In some cases, the capacitor can have a higher energy density in one temperature range than in another temperature range.

[0091] One or more components of the capacitors described herein, such as electrodes or dielectric materials, including leather fibers, leather powder, sawdust, or derivatives thereof, may be used as components for other power or energy storage systems such as batteries (e.g., solid-state batteries), fuel cells, electrochemical cells, rechargeable cells (e.g., secondary cells), or other storage systems. For example, a battery may comprise one or more electrodes including leather fibers, leather powder, sawdust, or derivatives thereof, such as an electrode described anywhere herein for use in a capacitor. Leather fibers, leather powder, sawdust, or derivatives thereof may be active materials for the electrodes. In some cases, a battery may comprise one electrode including leather fibers, leather powder, sawdust, or derivatives thereof. In some cases, a battery may comprise two electrodes, each containing the same or different compositions of leather fibers, leather powder, sawdust, or derivatives thereof. The power or energy storage system may include other plant-derived materials (e.g., hemp-derived, flax-derived, etc.).

Example

[0092] (Example)

[0093] In one embodiment, the electrodes for use in a capacitor were formed by carbonizing and activating the hydrothermal product of ramie fiber. Ramie fiber and diluted sulfuric acid were sealed inside a steel autoclave. The autoclave was heated at 180 °C for 24 hours and then cooled to room temperature (e.g., about 20 - 25 °C). The contents inside the autoclave were filtered, washed with distilled water, dried, resulting in a carbonaceous solid (e.g., biochar). Biochar and potassium hydroxide (KOH) were mixed at a 1:1 mass ratio, and the mixture was heated under an argon flow at 700 - 800 °C (e.g., 3 °C / min) for 1 hour. The activated sample was then washed with 10 wt% (weight %) hydrochloric acid (HCl) and distilled water. The carbon was dried in an oven at 100 °C for 12 hours. The carbon nanosheet (CNS - 700) activated at 700 °C through the above process has a surface area density of 1690 square meters / gram (m 2 g -1 ), and the carbon nanosheet (CNS - 750) activated at 750 °C through the above process has a surface area density of 2287 m 2 g -1 . The carbon nanosheet (CNS - 800) activated at 800 °C through the above process has a surface area density of 1505 m 2 g -1 . The electrical conductivities of CNS - 700, CNS - 750, and CNS - 800 are 217 Siemens / meter (S m -1 ), 211 S m -1 , and 226 S m -1 , respectively. At an operating temperature of 20 °C, CNS - 750 and CNS - 800 exhibit energy densities of 19 watt - hour / kilogram (Wh kg -1 ) and 18 Wh kg -1 , respectively. At an operating temperature of 60 °C, CNS - 750 and CNS - 800 exhibit energy densities of 34 Wh kg -1 and 31 Wh kg -1 , respectively. At an operating temperature of 100 °C, CNS - 750 and CNS - 800 are 40 Wh kg-1 and 34 Wh / kg -1 showed an energy density of. The maximum power density CNS-800 at operating temperatures of 20 °C, 60 °C, and 100 °C was 28 kilowatts per kilogram (kW / kg -1 ), 49 kW / kg -1 , and 77 kW / kg -1 , respectively. CNS-800 was able to retain 96% of its initial capacitance even after 10,000 cycles.

[0094] Preferred embodiments of the present invention are shown and described herein, but it will be apparent to those skilled in the art that such embodiments are provided by way of example only. It is not intended that the present invention be limited by the specific examples provided herein. The present invention is described with reference to the foregoing specification, but the description and illustration of the embodiments herein are not intended to be construed in a limiting sense. Numerous variations, modifications, and substitutions will occur to those skilled in the art without departing from the present invention. Furthermore, it should be understood that all aspects of the present invention are not limited to the specific depictions, 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 may be employed in practicing the present invention. Accordingly, the present invention is also considered to cover any such alternatives, modifications, variations, or equivalents. The following claims define the scope of the present invention, and it is intended that methods and structures within the scope of these claims and their equivalents be covered.

Claims

[Claim 1] The invention as described in the drawings.

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