KR20160129229A - Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method - Google Patents
Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method Download PDFInfo
- Publication number
- KR20160129229A KR20160129229A KR1020150061001A KR20150061001A KR20160129229A KR 20160129229 A KR20160129229 A KR 20160129229A KR 1020150061001 A KR1020150061001 A KR 1020150061001A KR 20150061001 A KR20150061001 A KR 20150061001A KR 20160129229 A KR20160129229 A KR 20160129229A
- Authority
- KR
- South Korea
- Prior art keywords
- electrode
- ultracapacitor
- graphene
- graphene oxide
- oxide
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
- H01G11/84—Processes for the manufacture of hybrid or EDL capacitors, or components thereof
- H01G11/86—Processes for the manufacture of hybrid or EDL capacitors, or components thereof specially adapted for electrodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
- H01G11/08—Structural combinations, e.g. assembly or connection, of hybrid or EDL capacitors with other electric components, at least one hybrid or EDL capacitor being the main component
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
- H01G11/22—Electrodes
- H01G11/30—Electrodes characterised by their material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/13—Energy storage using capacitors
Abstract
The present invention relates to a method for producing a graphene oxide, comprising the steps of: forming a graphite oxide; introducing the graphite oxide into a polar solvent; and peeling the graphite oxide by ultrasonic treatment to form a graphene oxide dispersion; Forming an electrode composition comprising the graphene oxide in the form of an ultracapacitor electrode, mixing the graphene oxide with the graphene oxide to form graphene oxide, And forming an electrode for an ultracapacitor by performing a reduction heat treatment on an electrode-shaped product including an oxide. The method for manufacturing an electrode for an ultracapacitor and the ultracapacitor cell using the electrode for an ultracapacitor manufactured using the method . According to the present invention, it is possible to minimize the content of the binder required for electrode formation, to prevent the phenomenon that graphene is layered again, and to utilize inherent properties such as excellent conductivity and high specific surface area of graphene .
Description
The present invention relates to a method of manufacturing an electrode for an ultracapacitor and an ultracapacitor cell, and more particularly, to a method of manufacturing an electrode for an ultracapacitor which can minimize the content of a binder necessary for electrode formation, And an ultracapacitor cell using the electrode for an ultra capacitor, which is manufactured by using the method. The present invention also relates to a method of manufacturing an electrode for an ultracapacitor, which can utilize inherent properties such as excellent conductivity and high specific surface area.
In general, an ultracapacitor is also referred to as an electric double layer capacitor (EDLC) or a supercapacitor, which is formed by a pair of electrodes and a conductor, each having a different sign at the interface between the electrode and the conductor, (Electric double layer) of the charge / discharge operation is used, and the deterioration due to the repetition of the charging / discharging operation is very small, so that the device is not required to be repaired. Accordingly, ultracapacitors are mainly used for IC (integrated circuit) backup of various electric and electronic devices. Recently, they have been widely used for toys, solar energy storage, HEV (hybrid electric vehicle) have.
Such an ultracapacitor generally includes two electrodes of a positive electrode and a negative electrode impregnated with an electrolytic solution, a separator of a porous material interposed between the two electrodes to allow only ion conduction and to prevent insulation and short circuit, A gasket for preventing leakage of electricity and preventing insulation and short-circuit, and a metal cap as a conductor for packaging them. Then, one or more unit cells (normally 2 to 6 in the case of a coin type) are stacked in series and the two terminals of the positive and negative electrodes are combined.
The performance of the ultracapacitor is determined by the electrode active material and the electrolyte. In particular, the main performance such as the capacitance is largely determined by the electrode active material. As such an electrode active material, activated carbon is mainly used.
As the applications of ultracapacitors are expanded, higher non-storage capacities and energy densities are required, and it is required to develop electrode capacitors exhibiting higher capacitive capacities.
A problem to be solved by the present invention is to minimize the amount of binder required for electrode formation and to prevent the phenomenon of graphene from being re-deposited and to improve the inherent properties of graphene such as excellent conductivity and high specific surface area A method of manufacturing an electrode for an ultracapacitor that can be utilized, and an ultracapacitor cell to which an electrode for an ultracapacitor manufactured using the method is applied.
The present invention relates to a method for producing a graphene oxide, comprising the steps of: forming a graphite oxide; introducing the graphite oxide into a polar solvent; and peeling the graphite oxide by ultrasonic treatment to form a graphene oxide dispersion; Forming an electrode composition comprising the graphene oxide in the form of an ultracapacitor electrode, mixing the graphene oxide with the graphene oxide to form graphene oxide, And forming an electrode for an ultracapacitor by performing a reduction heat treatment on an electrode-shaped molding containing an oxide.
The step of forming the graphite oxide comprises mixing graphite, H 2 SO 4 , K 2 S 2 O 8 and P 2 O 5 with stirring, cooling the resultant mixture to room temperature, adding and leaving distilled water, , that by selectively separating the precipitate from the left output stage and, optionally dispersing the precipitate came up separated in distilled water, H 2 SO 4 and KMnO adding a 4 and H 2 SO 4 and KMnO 4 was added resulting Adding H 2 O 2 to the solution to which distilled water has been additionally added to cause the color of the solution to change to bright yellow while bubbling occurs, and selectively separating the precipitate from the solution changed to bright yellow.
The binder is preferably mixed in an amount of 1 to 20 parts by weight based on 100 parts by weight of the graphene oxide.
The molding step includes a step of rolling the composition for electrodes using a roll press molding machine to form a sheet-like electrode. The pressing pressure applied to the electrode composition by the roll press molding machine is 1 - 20 ton / cm < 2 >, the heating temperature applied to the electrode composition is in the range of 40 to 150 DEG C, and the electrode type of the sheet type preferably has an average thickness of 100 to 300 mu m.
The reduction heat treatment is preferably performed at a temperature of 150 to 350 캜 in a vacuum atmosphere.
The present invention also provides a method for manufacturing an ultracapacitor, comprising: preparing a positive electrode comprising an electrode for an ultracapacitor produced by the above production method, a negative electrode including an electrode for an ultracapacitor manufactured by the manufacturing method, and a negative electrode disposed between the positive electrode and the negative electrode, And a gasket for sealing the metal cap, wherein the cathode, the separator, and the cathode are disposed inside the metal cap, and the metal cap is filled with the electrolyte. to provide.
The present invention also provides a method of manufacturing a thin film transistor comprising a first separator for preventing a short circuit, an anode including an electrode for an ultracapacitor manufactured by the manufacturing method, a second separator for preventing a short circuit between the anode and the cathode, A first lead connected to the negative electrode, a second lead connected to the positive electrode, and a second lead connected to the positive electrode, wherein the negative electrode includes an electrode for an ultracapacitor, And a seal rubber for sealing the metal cap, wherein the roll revolver is impregnated with an electrolytic solution.
The electrode can be manufactured by coating the current collector with a graphene or a rubber (sheet) after preparing graphite oxide by peeling the graphite oxide and reducing the graphene oxide, In general, as the content of the binder used in the production of the activated carbon electrode for the ultracapacitor, it is required to use a relatively larger amount of the binder due to the high specific surface area of the graphene. In the electrode manufacturing process, The re-stacking results in a reduction in specific surface area and electrical conductivity of the graphene, resulting in a decrease in the non-storage capacity and output characteristics of the ultracapacitor.
According to the present invention, it is possible to manufacture a rubber (sheet) electrode in the form of graphene oxide, which is a step before reduction to graphene, to minimize the amount of binder required for electrode formation, , It is possible to prevent re-layering between graphenes and to prevent the phenomenon that graphenes are re-deposited, which is useful for exploiting inherent properties such as excellent conductivity and high specific surface area of graphene. It is possible to reduce the non-storage capacity and the output characteristics when applied to an ultracapacitor because the re-layering between graphenes occurs at the time of rolling using the composition for electrode including graphene. However, in the case of the present invention, The graphene oxide constituting the composition for use in the present invention is in an oxide state, and the graphene oxide and the graphene oxide are not chemically bonded to each other, and the graphene oxides in the layered structure are kept apart from each other, Do not.
1 is a cross-sectional view of a coin type ultracapacitor according to an example.
FIGS. 2 to 5 are views showing a winding type ultracapacitor according to an example.
6 is a photograph showing the composition sheet for electrodes prepared according to Experimental Example.
7 is a photograph showing an electrode for an ultracapacitor manufactured according to an experimental example.
8 is a graph showing charging and discharging curves of an electrode for an ultracapacitor manufactured according to an experimental example and an electrode manufactured according to a comparative example.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it should be understood that the following embodiments are provided so that those skilled in the art will be able to fully understand the present invention, and that various modifications may be made without departing from the scope of the present invention. It is not. Wherein like reference numerals refer to like elements throughout.
Due to its high specific surface area and electrical conductivity, graphene can be widely used as a secondary battery material including an ultracapacitor. However, graphenes require the use of a large number of binders in the case of a coating method or an electrode in the form of a rubber (sheet), and a re-layering occurs between graphenes during the rolling and drying process, Which causes a decrease in non-storage capacity and output characteristics when applied to a capacitor.
Therefore, in the present invention, graphen oxide having a relatively larger weight than graphene is used by the functional group to minimize the content of the binder, thereby forming an electrode, and an electrode is formed by thermally reducing the electrode- And to simplify the electrode process.
When the electrode is manufactured, the graphite oxide is peeled off to prepare graphene oxide, and the graphene is produced by reducing the graphene oxide. Then, the electrode composition containing the graphene is coated on the current collector or made of rubber (sheet) It is generally required to use a relatively large amount of binder due to the high specific surface area of graphene as a binder used in the production of an activated carbon electrode for an ultracapacitor. The re-stacking between the graphenes in the process results in a reduction in specific surface area and electrical conductivity of the graphene, resulting in a decrease in the non-storage capacity and output characteristics of the ultracapacitor.
Accordingly, in the present invention, it is possible to manufacture a rubber (sheet) electrode in the form of graphene oxide, which is a step prior to reduction to graphene, to minimize the amount of binder required for electrode formation, , It is possible to prevent re-layering between graphenes. By preventing the phenomenon of graphene from being redeposited, it is useful to take advantage of inherent properties such as excellent conductivity and high specific surface area of graphene.
According to a preferred embodiment of the present invention, there is provided an electrode for an ultracapacitor comprising the steps of: forming a graphite oxide; injecting the graphite oxide into a polar dispersing medium; separating the graphite oxide by ultrasonic treatment to form a graphene oxide dispersion; Forming a composition for electrode in a kneaded state by mixing a dispersion medium and a binder in the graphene oxide dispersion; molding the electrode composition containing graphene oxide in the form of an ultracapacitor electrode; Forming an electrode for an ultracapacitor by reducing heat treatment of an electrode-shaped molding containing the graphene oxide to reduce it to graphene.
The step of forming the graphite oxide comprises mixing graphite, H 2 SO 4 , K 2 S 2 O 8 and P 2 O 5 with stirring, cooling the resultant mixture to room temperature, adding and leaving distilled water, , that by selectively separating the precipitate from the left output stage and, optionally dispersing the precipitate came up separated in distilled water, H 2 SO 4 and KMnO adding a 4 and H 2 SO 4 and KMnO 4 was added resulting Adding H 2 O 2 to the solution to which distilled water has been additionally added to cause the color of the solution to change to bright yellow while bubbling occurs, and selectively separating the precipitate from the solution changed to bright yellow.
The binder is preferably mixed in an amount of 1 to 20 parts by weight based on 100 parts by weight of the graphene oxide.
The molding step includes a step of rolling the composition for electrodes using a roll press molding machine to form a sheet-like electrode. The pressing pressure applied to the electrode composition by the roll press molding machine is 1 - 20 ton / cm < 2 >, the heating temperature applied to the electrode composition is in the range of 40 to 150 DEG C, and the electrode type of the sheet type preferably has an average thickness of 100 to 300 mu m.
The reduction heat treatment is preferably performed at a temperature of 150 to 350 캜 in a vacuum atmosphere.
An ultracapacitor cell according to a preferred embodiment of the present invention includes an anode including an electrode for an ultracapacitor manufactured by the manufacturing method, a cathode including an electrode for an ultracapacitor manufactured by the manufacturing method, A separation membrane disposed between the anode and the cathode to prevent short-circuiting between the anode and the cathode, and a gasket disposed inside the anode, the separation membrane and the cathode, the metal cap having an electrolyte injected therein, and a gasket for sealing the metal cap .
According to another aspect of the present invention, there is provided an ultracapacitor cell including: a first separator for preventing a short circuit; an anode including an electrode for an ultracapacitor manufactured by the manufacturing method; A second separator, and a negative electrode including an electrode for an ultracapacitor manufactured by the above-described method are sequentially stacked to form a coiled roll, a first lead connected to the negative electrode, and a second lead connected to the positive electrode, 2 lead wire, a metal cap for accommodating the roll revolver, and a sealing rubber for sealing the metal cap, wherein the roll revolver is impregnated with the electrolytic solution.
Hereinafter, a method for manufacturing an electrode for an ultracapacitor according to a preferred embodiment of the present invention will be described in more detail.
The carbon material is generally classified into three-dimensional diamond and graphite, two-dimensional graphene, one-dimensional carbon nanotube, and zero-dimensional buckyball depending on its structure. Graphene is a term made by combining graphite, which means graphite, and suffix -ene, which means a molecule having a double bond of carbon. Three out of four outermost electrons constituting graphene form a sp 2 hybrid orbital, forming a strong covalent σ bond, while the remaining one electron forms a π bond with other carbons around it, Shape 2-dimensional structure. The single-layer graphene has a thickness of about 0.34 nm and is very thin and has excellent mechanical strength, thermal and electrical properties, flexibility and transparency.
Grapin became widely known as Novoselov and Professor Geim of the University of Manchester announced the world's first method of separating graphene from pencil lead graphite using the adhesion of Scotch tape. First, prepare graphite flakes, conventional scotch tape, and SiO 2 wafers. The prepared flakes are put on a scotch tape and folded several times and repeated. After this process is completed, the tape is placed on a SiO 2 wafer, rubbed off the remaining flake marks, and the tape is removed to obtain a multi-layered graphene from one layer of graphene.
The reason why this method is possible is to look at the atomic structure of graphene. Graphene has three carbon atoms forming a strong covalent bond on a two-dimensional plane, while a relatively weak van der Waals force in the vertical direction, resulting in very low coefficient of friction between layers, resulting in weak adhesion of the scotch tape It becomes possible to separate it. The exfoliated graphene was very simple to prepare for the sample, and exhibited excellent electrical and structural properties, which played a role in rapidly spreading the basic research of graphene. However, since the area is only micrometer level and the yield is low, there is a limit to the manufacturing method for various applications.
The fracture stress of graphene is ~ 40 N / m, the theoretical limit value is about 125 GPa, and the modulus of elasticity is about ~ 1.0 TPa which is more than 200 times of steel. This is because there is a hard carbon bond and there is no bond in the fault. It can also be increased by 20% in a plane axis direction, which is much higher than any other crystal. Also, as temperature rises, graphene continues to shrink by two-dimensional phonons, and at the same time it has a very flexible, yet well-cracked characteristic when pulled strongly.
Graphene has a thermal conductivity of about 5,000 W / m · K at room temperature, which is superior to carbon nanotubes or diamond. It is 50% higher than carbon nanotubes and 10 times larger than metals such as copper and aluminum. This is because graphene can easily transmit atomic vibrations. This excellent thermal conductivity also affects the long average free path of electrons. On the other hand, graphite with graphene laminate has a disadvantage in that the thermal conductivity (about 100 times) is significantly lowered in the vertical direction.
The maximum electron mobility of graphene at room temperature is about 200,000 cm 2 / Vs. This is known to be due to the very small degree of scattering of electrons in the case of graphene, which leads to a long average free path. Therefore, resistance is lower than 35% of copper with very low resistance. Also, in the case of graphene, it does not lose its electrical conductivity even when the area is increased or decreased by more than 10%.
Generally, top-down graphene production methods using graphite can be classified into three types of mechanical peeling, chemical peeling, and non-oxidative peeling.
Mechanical exfoliation refers to the removal of mechanical forces from graphite crystals consisting of van der Waals weak bonds. As if a thin film peeled off smoothly from a pencil lead and the writing was written, it was made from graphene using graphite crystals. This method is possible because electrons of the π-orbital of graphene spread widely on the surface and have a smooth surface.
The chemical stripping method is a method based on a solvent that uses an oxidation and reduction reaction and is the closest to the two goals of large area growth and mass production of graphene.
In general, graphite oxide is readily dispersible in water (distilled water) and is present as a thin film plate (graphite oxide consisting of tens to hundreds of layers) negatively charged in a polar solvent. A stripping process is required to form the dispersed graphite oxide thin film plate with graphene oxide.
The most widely used exfoliation method is ultrasonicagitation, and there is a method of separating the layer of expanded graphite oxide through rapid heating. Graphite oxide is made in the form of a brown viscous slurry and is formed from graphite oxide, a stripped thin film oxidation plate, a piece of unoxidized graphite, and residues of oxidizing agent. Graphite oxide is subjected to purification through centrifugation and the like. The refined graphite oxide is peeled off in the form of graphene oxide through ultrasonic treatment.
Hereinafter, the method of forming graphene oxide will be described in more detail. However, the method of synthesizing graphene oxide is not limited to the method described later.
Graphite, H 2 SO 4 , K 2 S 2 O 8 and P 2 O 5 are mixed at a temperature higher than room temperature (for example, 60 to 99 ° C) while stirring. Wherein the K 2 S 2 O 8 and P 2 O 5 are mixed in a weight ratio of 1: 0.1 to 10, and the H 2 SO 4 is mixed with the total content of K 2 S 2 O 8 and P 2 O 5 by 1 : 1 to 20 by volume. The resultant mixture is reacted at a temperature higher than room temperature by using a hot plate or the like. The temperature is preferably about 60 to about 99 DEG C, and the reaction is preferably performed for about 1 to about 48 hours.
Cool the resulting mixture to room temperature, add distilled water, and allow to stand. It is preferable that the abovementioned leaving is performed for about 6 to 72 hours.
The precipitate is selectively separated from the neglected result.
Selective precipitate is washed with distilled water to remove remaining acid or base. The precipitate is dispersed in distilled water and H 2 SO 4 and KMnO 4 are added. H 2 SO 4 and KMnO 4 are preferably added slowly at a temperature lower than room temperature (for example, -5 ° C to 4 ° C).
Add H 2 SO 4 and KMnO 4 to distilled water and add H 2 O 2 to distilled water to make the solution yellow.
The precipitate is selectively separated from the solution which turns bright yellow. Selective precipitate is washed with distilled water to remove remaining acid or base. In this way, graphite oxide can be obtained.
The graphite oxide is peeled off from a polar solvent containing water (distilled water) by ultrasonic waves to form a graphene oxide dispersion. The graphite oxide is peeled off by ultrasonic treatment to obtain a graphene oxide dispersion. The graphene oxide may be in the form of a single layer, a bilayer, or a multilayer. The polar solvent may be an amide type such as dimethylformamide (DMF), a pyrrolidone type such as N-methylpyrrolidone (NMP), an alcohol type such as ethanol, a dimethylsulfoxide ; DMSO), nitrile such as acetonitrile, ketone such as acetone, tetrahydrofuran (THF), ether such as diethylether, toluene (toluene) toluene, and 1,2-dichlorobenzene (DCB), it is more effective to use a solvent having a high polarity and particularly a hydrogen bond.
A solvent and a binder are mixed in the graphene oxide dispersion to form a paste composition for electrodes.
The binder is preferably mixed in an amount of 1 to 20 parts by weight based on 100 parts by weight of the graphene oxide (solid content). The binder may be selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidene difluoride (PVDF), carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), polyvinyl butyral polyvinyl butyral (PVB), poly-N-vinylpyrrolidone (PVP), styrene butadiene rubber (SBR), polyamide-imide, polyimide, And the like can be used alone or in combination.
The dispersion medium may be an organic solvent such as ethanol (EtOH), acetone, isopropyl alcohol, N-methylpyrrolidone (NMP), propylene glycol (PG) or water.
Since the electrode composition is in the paste form, uniform mixing (complete dispersion) may be difficult. When the mixture is stirred for a predetermined time (for example, 1 minute to 12 hours) using a mixer such as a high-speed mixer, Can be obtained.
The composition for electrode comprising the graphene oxide is formed into an ultracapacitor electrode. The electrode composition may be formed into an electrode shape by pressing the electrode composition, or may be formed into an electrode shape by coating the electrode composition with a metal foil. Alternatively, the electrode composition may be rolled into a sheet state, .
More specifically explaining an example of formation in an electrode form, the electrode composition can be pressed (rolled) by using a roll press molding machine. The roll press forming machine aims at improving the electrode density through rolling and controlling the thickness of the electrode. The roll press forming machine is provided with a controller capable of controlling the thickness and heating temperature of rolls and rolls at the upper and lower ends, ≪ / RTI > As the electrode in the roll state passes the roll press, the rolling process is carried out and the roll is rolled again to complete the electrode. At this time, the pressing pressure of the press is preferably 1 to 20 ton / cm 2, and the roll temperature is preferably 40 to 150 캜. It is possible to reduce the non-storage capacity and the output characteristics when applied to an ultracapacitor because the re-layering between graphenes occurs at the time of rolling using the composition for electrode including graphene. However, in the case of the present invention, The graphene oxide constituting the composition for use in the present invention is in an oxide state, and the graphene oxide and the graphene oxide are not chemically bonded to each other, and the graphene oxides in the layered structure are kept apart from each other, Do not.
In order to reduce the graphene oxide to graphene, an electrode-shaped molded article containing the graphene oxide is subjected to reduction heat treatment to form an electrode for an ultracapacitor. The reduction heat treatment is preferably performed in a vacuum atmosphere at a temperature of 150 ° C to 350 ° C. The reduction heat treatment is preferably performed at the above temperature for about 10 minutes to 48 hours. Such a reduction heat treatment step improves the strength of the electrode for an ultracapacitor while simultaneously drying the composition for electrode (evaporation of the dispersion medium).
The electrode for an ultracapacitor manufactured as described above can be applied to a small coin type ultracapacitor with a high capacity.
FIG. 1 is a sectional view of a coin-type ultracapacitor cell to which the electrode 10 for an ultracapacitor is applied, according to an embodiment of the present invention. 1,
The coin-type ultracapacitor cell includes an
The separator may be a battery such as a polyethylene nonwoven fabric, a polypropylene nonwoven fabric, a polyester nonwoven fabric, a polyacrylonitrile porous separator, a poly (vinylidene fluoride) hexafluoropropane copolymer porous separator, a cellulose porous separator, a kraft paper or a rayon fiber, And is not particularly limited as long as it is a membrane commonly used in the field.
On the other hand, the electrolyte charged in the ultracapacitor is mixed with at least one solvent selected from the group consisting of propylene carbonate (PC), acetonitrile (AN) and sulfolane (SL), tetraethylammonium tetrafluoborate (TEABF4) and triethylmethylammonium tetrafluoborate ) May be used. The electrolytic solution may contain at least one ionic liquid selected from 1-ethyl-3-methyl imidazolium tetrafluoroborate (EMIBF4) and 1-ethyl-3-methyl imidazolium bis (trifluoromethanesulfonyl) imide.
FIGS. 2 to 5 are views showing an ultracapacitor cell according to another example, and a method of manufacturing the ultracapacitor cell will be described in detail with reference to FIGS. 2 to 5. FIG.
As shown in FIG. 2, lead
3, the
The
As shown in Fig. 4, a sealing
The electrolytic solution is injected so that the roll-shaped winding element 175 (the
The ultracapacitor cell thus fabricated is schematically shown in Fig.
Hereinafter, experimental examples according to the present invention will be specifically shown, and the present invention is not limited to the following experimental examples.
Natural graphite of 3g (150㎛, Sigma Aldrich), H 2 SO 4 of 12㎖ (95%, Samchun Chemicals), of 2.5g K 2 S 2 O 8 (Sigma-Aldrich) and 2.5g of P 2 O 5 (Sigma Aldrich) were mixed and stirred at 80 DEG C for 5 hours. The mixture was then cooled to room temperature, 500 ml of distilled water was added slowly and allowed to stand for 24 hours.
The precipitates separated from the mixture were washed with distilled water to remove remaining acids and salts, and then dispersed in distilled water. The temperature was maintained at 0 ° C, 120 ml of H 2 SO 4 and 15 g of KMnO 4 (Sigma Aldrich) .
After the mixture was stirred again at 35 DEG C for 2 hours, 250 mL of distilled water was added slowly. The mixture was stirred for another 2 hours and 700 ml of distilled water was added thereto.
Then, 20 mL of H 2 O 2 (34.5%) was added, and the color of the solution turned bright yellow upon bubble formation. A precipitate was obtained from this solution and washed with 10% HCl (v / v) and distilled water to obtain graphite oxide.
1 g of the synthesized graphite oxide was added to 25 ml of distilled water, and the graphite oxide was peeled by ultrasonic treatment for 1 hour to prepare a graphene oxide dispersion.
25 ml of anhydrous ethanol was added to the prepared graphene oxide dispersion, and the mixture was mixed using a high-speed mixer. Polytetrafluoroethylene (PTFE) as a binder was weighed in 5 parts by weight based on 100 parts by weight of graphene oxide And the mixture was further stirred at a high speed for 10 minutes at a speed of 2000 rpm using a high-speed mixer to prepare a kneaded state.
The kneaded composition for electrode was molded in a roll press molding machine until the surface became smooth. The roll press molding machine includes an upper roll and a lower roll, and the composition for electrode is passed between the upper roll and the lower roll to form the roll. The resultant product passed between the upper roll and the lower roll was folded in half, and the process of passing the upper product between the upper roll and the lower roll was repeated 15 times to obtain a composition sheet for a electrode having a smooth surface. The pressure applied to the electrode composition was about 10 ton / cm 2, and the heating temperature was about 60 ° C. FIG. 6 is a photograph showing the composition sheet for electrodes thus formed, and the electrode composition sheet had a thickness of about 150 .mu.m.
In order to reduce graphene oxide to graphene, the electrode composition sheet was subjected to reduction heat treatment in a vacuum drier at 300 캜 for 6 hours to obtain an electrode for an ultracapacitor. The reduction heat treatment was performed in a vacuum atmosphere. 7 is a photograph showing an electrode for an ultracapacitor.
The ultra-capacitor electrode thus manufactured was punched to have a diameter of 12 mm and used as an anode and a cathode of an ultracapacitor cell.
The ultracapacitor cell fabricated using an electrode for an ultra capacitor was assembled into a full cell with a coin type cell (2032). The membrane used was TF4035 from NKK. The electrolytic solution was prepared by dissolving 1 M of TEABF 4 in an acetonitrile solvent.
<Comparative Example>
Natural graphite of 3g (150㎛, Sigma Aldrich), H 2 SO 4 of 12㎖ (95%, Samchun Chemicals), of 2.5g K 2 S 2 O 8 (Sigma-Aldrich) and 2.5g of P 2 O 5 (Sigma Aldrich) were mixed and stirred at 80 DEG C for 5 hours. The mixture was then cooled to room temperature, 500 ml of distilled water was added slowly and allowed to stand for 24 hours.
The precipitates separated from the mixture were washed with distilled water to remove remaining acids and salts, and then dispersed in distilled water. The temperature was maintained at 0 ° C, 120 ml of H 2 SO 4 and 15 g of KMnO 4 (Sigma Aldrich) .
After the mixture was stirred again at 35 DEG C for 2 hours, 250 mL of distilled water was added slowly. The mixture was stirred for another 2 hours and 700 ml of distilled water was added thereto.
Then, 20 mL of H 2 O 2 (34.5%) was added, and the color of the solution turned bright yellow upon bubble formation. A precipitate was obtained from this solution and washed with 10% HCl (v / v) and distilled water to obtain graphite oxide.
1 g of the synthesized graphite oxide was added to 25 ml of distilled water, and the graphite oxide was peeled by ultrasonic treatment for 1 hour to prepare a graphene oxide dispersion.
Hydrazine hydrate is added to the graphene oxide dispersion and the resultant hydrazine hydrate is added is reacted in a heating mantle at a temperature of 80 DEG C higher than room temperature for 12 hours to chemically reduce the graphene oxide Pin (a reduced product of graphene oxide).
The thus prepared graphene was placed in 25 ml of anhydrous ethanol and mixed using a high-speed mixer. Then, 5 parts by weight of polytetrafluoroethylene (PTFE) as a binder was weighed out based on 100 parts by weight of graphene based on the solid content, And the mixture was kneaded at high speed using a high-speed mixer at a speed of 2000 rpm for 10 minutes.
The kneaded composition for electrode was molded in a roll press molding machine until the surface became smooth. The roll press molding machine includes an upper roll and a lower roll, and the composition for electrode is passed between the upper roll and the lower roll to form the roll. The resultant product passed between the upper roll and the lower roll was folded in half, and the process of passing the upper product between the upper roll and the lower roll was repeated 15 times to obtain a composition sheet for a electrode having a smooth surface. The pressure applied to the electrode composition was about 10 ton / cm 2, and the heating temperature was about 60 ° C. The electrode composition sheet had a thickness of about 150 mu m.
The electrode composition sheet was dried in a dryer at 300 캜 for 6 hours to obtain an electrode for an ultracapacitor. The drying was performed in a vacuum atmosphere.
The ultra-capacitor electrode thus manufactured was punched to have a diameter of 12 mm and used as an anode and a cathode of an ultracapacitor cell.
The ultracapacitor cell fabricated using an electrode for an ultra capacitor was assembled into a full cell with a coin type cell (2032). The membrane used was TF4035 from NKK. The electrolytic solution was prepared by dissolving 1 M of TEABF 4 in an acetonitrile solvent.
The results of charging and discharging of the ultracapacitor cell manufactured according to the experimental and comparative examples are shown in Table 1 below.
8 is a graph showing charging and discharging curves of an ultracapacitor cell manufactured according to an experimental example and an ultracapacitor cell manufactured according to a comparative example. 8A is a graph of an ultracapacitor cell manufactured according to an experimental example, and FIG. 8B is a graph of an ultracapacitor cell manufactured according to a comparative example. The charging and discharging voltages were 0.1 to 2.7 V and the current was 0.1 A / g.
Referring to Table 1 and FIG. 8, as a result of charging and discharging, the ultracapacitor cell manufactured according to the experimental example exhibited a higher discharge capacity than the ultracapacitor cell manufactured according to the comparative example, The prepared ultracapacitor cell was found to be lower than the ultracapacitor cell manufactured according to the comparative example.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, This is possible.
110: cathode 120: anode
130: first lead wire 140: second lead wire
150: first separator 160: second separator
170: Adhesive tape 175: Winding element
180: sealing rubber 190: metal cap
192: Gasket
Claims (7)
Introducing the graphite oxide into a polar solvent, and peeling the graphite oxide by ultrasonic treatment to form a graphene oxide dispersion;
Mixing a dispersion medium and a binder in the graphene oxide dispersion to form a paste composition;
Molding the electrode composition containing graphene oxide in the form of an ultracapacitor electrode; And
And forming an electrode for an ultracapacitor by reducing heat treatment of an electrode-shaped molding containing the graphene oxide to reduce the graphene oxide to graphene.
Mixing graphite, H 2 SO 4 , K 2 S 2 O 8 and P 2 O 5 with stirring;
Cooling the resultant mixture to room temperature, adding distilled water and allowing it to stand;
Selectively separating the precipitate from the neglected result;
Dispersing the selectively separated precipitate in distilled water, adding H 2 SO 4 and KMnO 4 ;
Adding H 2 O 2 to the solution to which distilled water has been additionally added to the resultant of addition of H 2 SO 4 and KMnO 4 , thereby changing the color of the solution to a bright yellow color as the foaming occurs; And
And selectively separating the precipitate from the solution turned into a light yellow color.
Rolling the electrode composition using a roll press molding machine to form a sheet type electrode,
The pressure applied to the electrode composition by the roll press molding machine is in the range of 1 to 20 ton /
The heating temperature applied to the electrode composition is in the range of 40 to 150 占 폚,
Wherein the electrode type of the sheet type has an average thickness of 100 to 300 mu m.
An anode comprising an electrode for an ultracapacitor manufactured by the method according to claim 1;
A separation membrane disposed between the anode and the cathode and for preventing a short circuit between the anode and the cathode;
A metal cap in which the anode, the separator, and the cathode are disposed and into which an electrolyte is injected; And
And a gasket for sealing the metal cap.
A first lead wire connected to the negative electrode;
A second lead wire connected to the positive electrode;
A metal cap for receiving the book revolver; And
And a sealing rubber for sealing the metal cap,
Wherein the roll revolver is impregnated in an electrolytic solution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020150061001A KR101729509B1 (en) | 2015-04-30 | 2015-04-30 | Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020150061001A KR101729509B1 (en) | 2015-04-30 | 2015-04-30 | Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| KR20160129229A true KR20160129229A (en) | 2016-11-09 |
| KR101729509B1 KR101729509B1 (en) | 2017-04-24 |
Family
ID=57529453
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020150061001A KR101729509B1 (en) | 2015-04-30 | 2015-04-30 | Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR101729509B1 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101079317B1 (en) | 2009-11-26 | 2011-11-04 | 한국세라믹기술원 | Manufacturing method of graphene electrode for supercapacitor and supercapacitor graphene electrode manufactured by the method |
-
2015
- 2015-04-30 KR KR1020150061001A patent/KR101729509B1/en active IP Right Grant
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101079317B1 (en) | 2009-11-26 | 2011-11-04 | 한국세라믹기술원 | Manufacturing method of graphene electrode for supercapacitor and supercapacitor graphene electrode manufactured by the method |
Also Published As
| Publication number | Publication date |
|---|---|
| KR101729509B1 (en) | 2017-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101815902B1 (en) | Manufacturing method of electrode active material for ultracapacitor and manufacturing method of ultracapacitor electrode using the electrode active material | |
| US10692660B2 (en) | Three-dimensional graphene framework-based high-performance supercapacitors | |
| US8845994B2 (en) | Electrode active material having high capacitance, method for producing the same, and electrode and energy storage device comprising the same | |
| JP5322435B2 (en) | Negative electrode active material for electricity storage devices | |
| US11545310B2 (en) | High capacitance composites | |
| KR20180061087A (en) | Dispersions of porous graphene materials and uses thereof | |
| KR20160114812A (en) | Manufacturing method of supercapacitor graphene electrode using reduced graphene oxide and supercapacitor cell using the supercapacitor electrode manufactured by the method | |
| KR101793040B1 (en) | Manufacturing method of electrode active material for ultracapacitor, manufacturing method of ultracapacitor electrode using the electrode active material and ultracapacitorusing the electrode active material | |
| KR101614299B1 (en) | Manufacturing method of ultracapacitor electrode with high density and supercapacitor cell using the ultracapacitor electrode manufactured by the method | |
| Khanra et al. | Electrochemical performance of reduced graphene oxide surface-modified with 9-anthracene carboxylic acid | |
| KR101635763B1 (en) | Composite for ultracapacitor electrode, manufacturing method of ultracapacitor electrode using the composite, and ultracapacitor manufactured by the method | |
| KR101166696B1 (en) | Supercapacitor and manufacturing method of the same | |
| KR102081616B1 (en) | Supercapacitor having excellent stability for high voltage and method for manufacturing the same | |
| KR101591264B1 (en) | Electrode active material, manufacturing method of the same and manufacturing method of ultra-capacitor electrode | |
| KR101537953B1 (en) | Manufacturing method of super capacitor electrode | |
| KR101771000B1 (en) | Manufacturing method of flexible ultracapacitor electrode and ultracapacitor using the ultracapacitor electrode | |
| KR102013173B1 (en) | Composite for ultracapacitor electrode, manufacturing method of ultracapacitor electrode using the composite, and ultracapacitor manufactured by the method | |
| KR101729509B1 (en) | Manufacturing method of ultracapacitor electrode and ultracapacitor cell using the ultracapacitor electrode manufactured by the method | |
| KR102188237B1 (en) | Composite for supercapacitor electrode, manufacturing method of supercapacitor electrode using the composite, and supercapacitor manufactured by the method | |
| KR101860755B1 (en) | Composite for ultracapacitor electrode, manufacturing method of ultracapacitor electrode using the composite, and ultracapacitor manufactured by the method | |
| KR102188242B1 (en) | Composite for supercapacitor electrode, manufacturing method of supercapacitor electrode using the composite, and supercapacitor manufactured by the method | |
| JP2008166309A (en) | Lithium ion capacitor | |
| Li et al. | In situ growth of ultrashort rice-like CuO nanorods supported on reduced graphene oxide nanosheets and their lithium storage performance | |
| JP2006310412A (en) | Lithium-ion capacitor | |
| KR102013179B1 (en) | Manufacturing method of electrode active material for supercapacitor, manufacturing method of supercapacitor electrode and manufacturing method of supercapacitor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A201 | Request for examination | ||
| E902 | Notification of reason for refusal | ||
| E701 | Decision to grant or registration of patent right | ||
| GRNT | Written decision to grant |