35results about How to "Higher than capacitance" patented technology

A method for making activated carbon materials for organic supercapacitors from straws, characterized in that crop straws are selected as raw materials, and the activated carbon materials for organic supercapacitors are obtained through the process steps of drying and crushing, carbonization, and activation in sequence. The activated carbon prepared by the method of the present invention has a large specific surface area, and when 1.2mol / l MeEt3NBF4 / AN is used as the electrolyte, the cyclic voltammetry test is carried out, and the specific capacitance is 232F / g at 2mv / s, which is suitable as an electrode material for organic supercapacitors .

High-density ordered graphene with an ion spacer layer and its preparation method and application, which relate to a high-density graphene material, its preparation method and its application in supercapacitors. The invention aims to solve the technical problems of low density and low volume specific capacitance of the existing graphene. The high-density ordered graphene with an ion spacer layer of the present invention has graphene sheets arranged in parallel in an orderly manner, and alkali metal ions are embedded between the graphene sheets to form a spacer layer, which is high-density graphene containing pores. Preparation method: reduce the graphene oxide aqueous dispersion in an alkaline reducing medium, and after washing, apply the graphene hydrogel directly on the current collector to form a thin film or grind it into a powder after drying. The material has high density, high volume specific capacitance, high rate performance and long cycle life. Electrode active materials that can be used in supercapacitors.

The invention employs a hydrothermal and calcination combined method to prepare a dual-oxide / graphene nanometer composite electrode material. The material has excellent electrochemical and energy-storage performance, and belongs to the technical field of material preparation and energy storage. The method is characterized by comprising the steps of respectively weighing a certain amount of cobalt source precursor and an aluminum source precursor and weighing a certain volume of distilled water in a small beaker, continuously adding a certain volume of graphene aqueous dispersion liquid, performing ultrasound for 30 minutes, dropwise adding a certain volume of ammonia water during stirring on a magnetic agitator, taking out a magnet, transferring a mixed solution to a stainless steel high-pressure reaction kettle containing a polytetrafluoroethylene liner, sealing the high-pressure reaction kettle, placing the high-pressure reaction kettle in a baking oven with a certain temperature, taking out the high-pressure reaction kettle after 12 hours, naturally cooling to a room temperature, performing centrifugation to obtain a precipitant, respectively washing the precipitant with the distilled water and alcohol for three times, and performing calcination on the precipitant for 3 hours under 300 DEG C to finally obtain the product. By the method, a surfactant is not needed to be used, the material is synthesized by one step, is high in yield and simple in preparation process and is suitable for industrial production, the specific capacitance value of the composite material is 968F / g when scanning current density is 1 A / g, and the retention rate still reaches 85% or above after circulation for 1,000 times.

The present invention is a kind of preparation method of flexible nano-porous nickel / nickel oxide composite electrode sheet, and the method comprises the following steps: the first step, prepare Ni-Ti precursor amorphous alloy strip, according to atomic percentage Ni:Ti=( 35+x): (65‑x), wherein, x=0~10, select high-purity Ni and Ti metals, and then smelt Ni‑Ti alloy ingots with electric arc melting furnaces; then Ni‑Ti alloy ingots Remove the superficial oxide skin, and use vacuum strip equipment to prepare Ni-Ti amorphous alloy thin strips to obtain Ni-Ti amorphous alloy thin strips with a thickness of 25-30 µm; in the second step, the Ni-Ti amorphous alloys obtained above are The strip is placed in an acidic corrosion solution at room temperature for free dealloying for 40-100 minutes, and then the obtained nanoporous thin strip is rinsed with deionized water to obtain a nanoporous nickel / nickel oxide composite electrode sheet. The composite electrode material prepared by the invention exhibits excellent flexibility and good electrochemical performance.

The invention relates to a nano-porous copper silver supported manganese dioxide electrode slice and a preparation method therefor. The cross section of the electrode slice comprises three layers. A middle core layer is an amorphous matrix. The other two sides are nano-porous copper silver. A hole wall and a surface of the nano-porous copper silver grow a layer of uniform thin manganese dioxide. The thickness of the electrode slice is about 25-35 mum. The thickness of an inside amorphous matrix layer is about 12-28 mum. The thickness of a single side of nano-porous copper silver or manganese dioxide composite electrode material layer is about 3-11 mum. The amorphous matrix comprises CuxZryAgz alloy components, wherein x is greater than or equal to 40 and less than or equal to 45, y is greater than or equal to 45 and less than or equal to 50, z is greater than or equal to 5 and less than or equal to 15, and x plus y plus z equals 100. The preparation method can realize independent support of the electrode slice. Compared with a conventional complicated process of flaking the electrode slice, the preparation method saves the step of adding substances such as a conductive agent, a binder and so on, thereby overcoming the defects in the prior art that active substances have poor dispersibility, are easy to fall off and have small effective specific surface area.

The invention discloses a preparation method of a polyaniline / carbon nano tube / nano-copper composite material, relates to a preparation method of the polyaniline / carbon nano tube composite material, and aims at solving the problems that the existing polyaniline / carbon nano tube composite material is low in electric conductivity and low in capacitance. The method is implemented as follows: firstly, putting a carbon nano tube into mixed acid, conducting backflow processing on the carbon nano tube and then conducting vacuum drying; secondly, acidizing the carbon nano tube, adding the acidized carbon nano tube into copper sulfate solution, adding NaOH solution and hydrazine hydrate solution respectively, heating, and then conducting vacuum drying to obtain nano copper / carbon nano tube composite powder; adding the nano copper / carbon nano tube into mixed solution of aniline and hydrochloric acid, then dropping ammonium persulfate solution, heating and conducting vacuum drying to obtain the polyaniline / carbon nano tube / nano-copper composite material. According to the preparation method, the size of the nano copper particles is 5-15nm, surface active agent is not needed, the nano copper can be prevented from being oxidized, the electric conductivity of the composite electrode materials is improved, the specific capacitance value is improved, and the preparation method is applied to the field of capacitor electrode materials.

The invention relates to a method for improving carbide derived carbon super capacitor performance. The method mainly comprises steps that firstly, acid solution of nitric acid and hydrofluoric acid is prepared according to a mole proportion of MHNO3:MHF of 1:2-2:1, secondly, to-be-treated carbide derived carbon is completely dipped into the acid solution, through ultrasonic concussion, air left on the carbide derived carbon is removed, under the 25-40 DEG C environment temperature, standing dipping for 48-264 hours is carried out, and lastly, washing is carried out till neutral property is realized, drying is then carried out, treatment on the carbide derived carbon is accomplished. The method is advantaged in that the method is simple and easy, cycle utilization of the acid solution can be realized, a raw material utilization rate is high, on the condition that excellent power characteristics of the carbide derived carbon and double electric layer characteristics are kept, a specific capacitance value is substantially improved, and excellent super capacitor performance is presented.

The invention discloses a method for preparing a nitrogen-containing porous carbon / manganese dioxide nanowire composite electrode for a supercapacitor, which uses nitrogen-containing biomass carbon and manganese dioxide as raw materials to prepare the electrode. First, manganese dioxide nanowires are synthesized by hydrothermal method, and then manganese dioxide nanowires, nitrogen-containing biomass carbon and silicon dioxide are mixed, followed by high-temperature carbonization and alkali etching, and finally a composite electrode material is formed. The prepared composite electrode material has a high specific capacitance value, at 2mol / L Ca(NO 3 ) 2 In the electrolyte, the specific capacity can reach up to 357.5F / g, and it has excellent cycle stability. After 5000 cycles, the specific capacity can still maintain 97.2%. The biomass carbon used in the invention is a renewable resource, and the manganese dioxide is an environment-friendly raw material, both of which have the characteristics of abundant raw materials and low cost. The composite electrode for supercapacitor prepared by the invention has excellent performance and simple operation, and can meet the application requirements of energy storage.

The invention discloses a preparation method of porous carbon and a product thereof. The preparation process of the method comprises the following steps: uniformly mixing a biomass carbon source, a structure-directing agent and water to obtain mixed liquor; carrying out a hydrothermal reaction; cooling, washing, drying and calcining to obtain the porous carbon, wherein the mass ratio of the structure-directing agent to the biomass carbon source is 1:5000-1:50; the structural guiding agent is ionic polyelectrolyte. The invention further discloses porous carbon prepared by using the method. The particle diameter of the porous carbon is 50-100 nanometers, the BET specific surface area is 1000-2000m<2> / g, the BJH beverage aperture is 2-10 nanometers, the pore volume is 0.8-1.2cm<3> / g, and meso pores account for 50-70 percent of the total pore volume. A super capacitor manufactured by taking the porous carbon as an electrode material has the advantages of high activity, low resistance and large specific capacitance, and the maximum specific capacitance value can be up to 223F / g.

The invention discloses graphene-based hydrogel and a preparation method thereof as well as a preparation method and an application of a supercapacitor electrode taking the graphene-based hydrogel as an active material, and relates to a graphene material and a preparation method thereof as well as a preparation method of a supercapacitor electrode. The invention aims at solving the technical problems that a conventional preparation method of the graphene-based hydrogel utilizes a toxic reducing agent and is complex in operation. The graphene-based hydrogel disclosed by the invention is hydrogel formed by graphene or graphene and an ungraphitised carbon material. The preparation method comprises the following steps of: after oxidizing graphite into graphite oxide, dispersing the graphite oxide separately or with the ungraphitised carbon material in water to obtain graphene-based colloidal dispersion through reduction; after rotary evaporation or rotary centrifugal treatment at reduced pressure, obtaining the graphene-based hydrogel through leaching or washing; and after coating the graphene-based hydrogel on an electrode current collector, immersing the electrode current collector in electrolyte for dipping to obtain the supercapacitor electrode which can be used as the anode and / or cathode of a supercapacitor.

The present invention provides a method for preparing a polyaniline / RuO2 / SnO2 composite electrode material, including: sputtering a SnO2 film onto a tantalum substrate by a magnetron sputtering method, to form a SnO2 layer; preparing porous-structured RuO2 nanoparticles with a uniform pore size distribution (10-15 nm) by a template method; and embedding polyaniline into the RuO2 nanoparticle matrix by a electrodeposition method, to finally obtain a multilayer-structured polyaniline / RuO2 / SnO2 composite electrode material with a specific capacitance value of 680-702 F·g−1 and an excellent cycling charge-discharge performance after it is assembled into an electrochemical capacitor.

The invention relates to a preparation method of a carbon particle / manganese dioxide composite electrode material, and the invention relates to a preparation method of a composite electrode material. The invention aims to solve the problems of high internal resistance and poor charge-discharge cycle stability existing in the existing manganese dioxide electrode material. The method of the present invention: mix manganese sulfate, potassium permanganate and distilled water evenly, place the substrate in the mixed solution, perform hydrothermal reaction to obtain the manganese dioxide nanosheet material, and place the manganese dioxide nanosheet material in the plasma The enhanced chemical vapor deposition vacuum device is used for deposition to obtain the carbon particle / manganese dioxide composite electrode material. The invention is used for a preparation method of a carbon particle / manganese dioxide composite electrode material.