摘要:
The disclosure relates to asymmetric supercapacitors containing: a positive electrode comprising a current collector and a first active material selected from a layered double hydroxide of formula [M2+1−xMx3+(OH)2]An−x/n·mH2O where M2+ is at least one divalent metal, M3+ is at least one trivalent metal and A is an anion of charge n−, where x is greater than zero and less than 1, n is 1, 2, 3 or 4 and m is 0 to 10; LiCoO2; LiCoxNiyO2 where x and y are greater than zero and less than 1; LiCoxNiyMn(1−x−y)O2 where x and y are greater than zero and less than 1; CoSx where x is from 1 to 1.5; MoS; Zn; activated carbon and graphite; a negative electrode containing a material selected from a carbonaceous active material, MoO3 and Li1xMoO6−x/2; an aqueous electrolyte solution or a non-aqueous ionic conducting electrolyte solution containing a salt and a salt and a non-aqueous solution; and a separator plate. Alternatively, the electrolyte can be a solid electrolyte.
摘要:
The disclosure relates to asymmetric supercapacitors containing: a positive electrode comprising a current collector and a first active material selected from a layered double hydroxide of formula [M2+1−xMx3+(OH)2]An−x/n·mH2O where M2+ is at least one divalent metal, M3+ is at least one trivalent metal and A is an anion of charge n−, where x is greater than zero and less than 1, n is 1, 2, 3 or 4 and m is 0 to 10; LiCoO2; LiCoxNiyO2 where x and y are greater than zero and less than 1; LiCoxNiyMn(1−x−y)O2 where x and y are greater than zero and less than 1; CoSx where x is from 1 to 1.5; MoS; Zn; activated carbon and graphite; a negative electrode containing a material selected from a carbonaceous active material, MoO3 and Li1xMoO6−x/2; an aqueous electrolyte solution or a non-aqueous ionic conducting electrolyte solution containing a salt and a salt and a non-aqueous solution; and a separator plate. Alternatively, the electrolyte can be a solid electrolyte.
摘要:
Asymmetric supercapacitors comprise: a positive electrode comprising a current collector and a first active material selected from the group consisting of manganese dioxide, silver oxide, iron sulfide, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, and a combination comprising at least one of the foregoing active materials; a negative electrode comprising a carbonaceous active material; an aqueous electrolyte solution selected from the group consisting of aqueous solutions of hydroxides of alkali metals, aqueous solutions of carbonates of alkali metals, aqueous solutions of chlorides of alkali metals, aqueous solutions of sulfates of alkali metals, aqueous solutions of nitrates of alkali metals, and a combination comprising at least one of the foregoing aqueous solutions; and a separator plate. Alternatively, the electrolyte can be a non-aqueous ionic conducting electrolyte or a solid electrolyte.
摘要:
Asymmetric supercapacitors comprise: a positive electrode comprising a current collector and a first active material selected from the group consisting of manganese dioxide, silver oxide, iron sulfide, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, and a combination comprising at least one of the foregoing active materials; a negative electrode comprising a carbonaceous active material; an aqueous electrolyte solution selected from the group consisting of aqueous solutions of hydroxides of alkali metals, aqueous solutions of carbonates of alkali metals, aqueous solutions of chlorides of alkali metals, aqueous solutions of sulfates of alkali metals, aqueous solutions of nitrates of alkali metals, and a combination comprising at least one of the foregoing aqueous solutions; and a separator plate. Alternatively, the electrolyte can be a non-aqueous ionic conducting electrolyte or a solid electrolyte.
摘要:
An asymmetric supercapacitor has a positive electrode having a current collector an active material selected from the group consisting of manganese dioxide, silver oxide, iron sulfide and mixtures thereof, a negative electrode having a carbonaceous active material carbon and optional current collector, an electrolyte, and a separator plate. In a preferred embodiment at least one of the electrodes has nanostructured/nanofibrous material and in a more preferred embodiment, both electrodes have nanostructured/nanfibrous material. The electrolyte can be liquid or solid although liquid electrolytes are preferred.The asymmetric supercapacitor has improved energy density by electrically coupling an electrode of high faradaic capacity such as one having manganese oxide (MnO2) with an electrode such as carbon that stores charge through charge separation at the electric double-layer. The asymmetric supercapacitor also improves power density by using high surface area nanostructured/nanofibrous electrode materials.
摘要:
Activated carbon blacks and the enhanced methods of preparing activated carbon blacks have been discovered. In order to form an activated carbon black, a conductive carbon black is coated with nanoparticles containing metal, and then catalytically activated in steam and an inert gas to form a catalytically activated mesoporous carbon black, where the mass of the catalytically activated carbon black is lower than the mass of the carbon black. The nanoparticles may serve as catalysts for activation rugosity of mesoporous carbon blacks. The catalytically activated carbon black material may be used in all manner of devices that contain carbon materials.
摘要:
A method of using carbon dioxide and low pH effluent from prior processing batches for synthesizing-carbon particles or hydrochar from carbohydrate/water solution formulations and conversion of aqueous feedstock containing carbohydrate waste. The hydrochar is a precursor material containing biochar solids and an acidic effluent. The hydrochar can be separated into solids (biochar) and liquid where the solids can be used for preparing a variety of carbonaceous products such as activated carbon. The carbohydrate/water formulation is heated in a pressure vessel converting solid waste to hydrochar forming uniform stable carbon nuclei and converting the aqueous carbohydrates in solution to solid spherical carbon particles. Microwave-assisted or inductive heating can be used as a preprocessing step to increase formation of carbon nuclei to accelerate growth of the carbon particles.
摘要:
A composition generally includes carbon particles. The particles are prepared by dissolving a carbohydrate-based precursor in water to form a precursor solution and placing the precursor solution in a pressure vessel. The precursor solution is placed in a pressure vessel. The pressure vessel is heated to a reaction temperature to form carbon particles. The carbon particles are subjected to a chemical activation and a physical activation. The composition includes, by weight, about 5% to about 30% oxygen.
摘要:
A composition generally includes carbon particles. The particles are prepared by dissolving a carbohydrate-based precursor in water to form a precursor solution and placing the precursor solution in a pressure vessel. The precursor solution is placed in a pressure vessel. The pressure vessel is heated to a reaction temperature to form carbon particles. The carbon particles are subjected to a chemical activation and a physical activation. The composition includes, by weight, about 5% to about 30% oxygen.
摘要:
A composition generally includes carbon particles. The particles are prepared by dissolving a carbohydrate-based precursor in water to form a precursor solution and placing the precursor solution in a pressure vessel. The precursor solution is placed in a pressure vessel. The pressure vessel is heated to a reaction temperature to form carbon particles. The carbon particles are subjected to a chemical activation and a physical activation. The composition includes, by weight, about 5% to about 30% oxygen.