KR101494615B1 - Manufacturing method of active carbon for supercapacitor electrode - Google Patents

Abstract

The present invention is characterized in that the surface is doped with at least one kind of hetero element selected from phosphorus (P), boron (B) and fluorine (F), the carbon (C) constituting the component and the dissimilar element are 1: 0.005 to 0.05 And a specific surface area in the range of 1,000 to 3,300 m ² / g. According to the present invention, at least one kind of heteroatom selected from phosphorus (P), boron (B) and fluorine (F) doped on the surface forms a covalent bond with carbon (C) to form a stable state under severe electrochemical conditions and high temperatures And the surface of the activated carbon doped with at least one heteroatom selected from phosphorus (P), boron (B) and fluorine (F) maintains hydrophobicity and is excellent in affinity with an organic solvent, It is possible to improve the energy density of the supercapacitor by improving penetration into the activated carbon.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing activated carbon for supercapacitor electrodes,

More particularly, the present invention relates to a method for producing activated carbon for supercapacitor electrodes comprising at least one heteroatom selected from phosphorus (P), boron (B) and fluorine (F) .

Generally, a supercapacitor is also referred to as an electric double layer capacitor (EDLC), a super-capacitor, or an ultra-capacitor, which is an electrode and a conductor, and an interface (Electric double layer) in which the sign is different from each other 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. As a result, supercapacitors are widely used in 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 a supercapacitor 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 enable ion conduction only 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 the coin type) are stacked in series and the two terminals of the positive and negative electrodes are combined.

The performance of the supercapacitor 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. Activated carbon is mainly used as the electrode active material, and the non-storage capacity based on the electrode of commercial products is known to be about 19.3 F / cc.

In recent years, as the applications of super capacitors have expanded, higher non-storage capacities and energy densities have been required.

However, the conventional activated carbon used as an electrode active material has a porous structure composed mainly of carbon (C). However, the active carbon used as an electrode active material has a porous structure mainly composed of hydrogen (H), oxygen (O), sulfur (S), nitrogen (N), and the like. These functional groups are known to aggravate the electrical properties of the cell. Particularly, oxygen (O) is decomposed and desorbed in the course of charge and discharge to generate gas such as CO and CO ₂ , thereby raising the internal pressure of the unit cell or decomposing the electrolyte in the unit cell to increase the life and energy density Has become a major cause of deterioration.

A problem to be solved by the present invention is to provide a super structure capable of suppressing deterioration of electrical characteristics of a cell due to functional groups such as hydrogen (H), oxygen (O), sulfur (S) And a method for producing activated carbon for a capacitor electrode.

The present invention is characterized in that the surface is doped with at least one kind of hetero element selected from phosphorus (P), boron (B) and fluorine (F), the carbon (C) constituting the component and the dissimilar element are 1: 0.005 to 0.05 Weight ratio, and a specific surface area of 1,000-3,300 m ² / g.

The activated carbon has a pore volume in the range of 0.70 to 1.30 cm 3 / g, and the activated carbon has micro pores in a range of 70 to 92%, and mesopores and macropores in a range of 8 to 30%.

At least two kinds of different elements selected from phosphorus (P), boron (B) and fluorine (F) may be complexly doped on the surface of the activated carbon.

(A) preparing activated carbon having a specific surface area in the range of 1,000 to 3,300 m ² / g, and (b) preparing at least one selected from phosphorus (P), boron (B) and fluorine (C) drying the activated carbon impregnated in the aqueous acid solution; and (d) drying the dried product in an inert atmosphere by microwave (B) and fluorine (F) is doped on the surface, and the carbon (C) constituting the component and the above-mentioned hetero atom are mixed in a weight ratio of 1: 0.005 to 0.05 Thereby obtaining an activated carbon for a super capacitor electrode.

The activated carbon doped with the hetero-element has a pore volume ranging from 0.70 to 1.30 cm 3 / g, a micro pore ranging from 70 to 92%, and a mesopore and macro pore ranging from 8 to 30%.

The acid aqueous solution may be at least one selected from the group consisting of an aqueous solution of phosphoric acid (H ₃ PO ₄ ), an aqueous solution of boric acid (H ₃ BO ₃ ) and an aqueous solution of hydrofluoric acid (HF) Is preferably used.

The acid aqueous solution may be a mixed acid aqueous solution of at least two selected from the group consisting of aqueous phosphoric acid (H ₃ PO ₄ ), boric acid (H ₃ BO ₃ ) and hydrofluoric acid (HF) , And the activated carbon in step (d) may be doped with at least two kinds of hetero elements selected from phosphorus (P), boron (B) and fluorine (F) on its surface.

The microwave treatment preferably uses an output of 100 to 1,500 W, and the inert atmosphere may be an argon (Ar) or nitrogen (N ₂ ) gas atmosphere.

According to the present invention, hydrogen (H), oxygen (O), sulfur (S), nitrogen (H), and the like are introduced by introducing one or more kinds of different elements selected from phosphorus (P), boron N) can be removed and deterioration of the electrical characteristics of the cell can be suppressed, and the lifetime and the energy density can be prevented from being lowered.

(H), oxygen (O), sulfur (S), and nitrogen (N) are formed on the surface of activated carbon by introducing at least one heteroatom selected from phosphorus (P), boron (B) (P), boron (B) or fluorine (F) is stabilized by bonding (covalent bonding) with carbon (C) which is the main component of activated carbon and is stable under severe electrochemical conditions and high temperature The long life characteristics of the unit cell are improved, the operating voltage is increased, and the energy density is improved.

1 is a schematic view showing a coin type super capacitor as a state of use of a super capacitor electrode.
2 is a view showing a state where a lead wire is attached to the positive electrode and the negative electrode.
3 is a view showing a state in which a book revoker is formed.
4 is a view showing a state in which the bookbinding canceller is inserted into the metal cap.
5 is a partially cut-away view of the supercapacitor.
6 is a graph showing the relationship between the amount of fluorine (F) introduced into the activated carbon for supercapacitor electrodes synthesized according to Example 1 and Example 2 and the ratio of the amount of fluorine (F) to the amount of carbon (C) X-ray photoelectron spectroscopy (XPS).
7 is a graph showing the results of XPS analysis for measuring the introduction of boron (B), the content of boron (B), and the ratio of hetero atoms to carbon in activated carbon for a super capacitor electrode synthesized according to Example 3 to be.
8 is a graph showing the results of XPS analysis for determining the introduction of phosphorus (P), the content of phosphorus (P), and the ratio of the hetero atoms to carbon in the activated carbon for the supercapacitor electrode synthesized according to Example 4 to be.
FIG. 9 is a graph showing the relationship between the capacitance of the activated carbon for the supercapacitor electrode synthesized according to the embodiment 1 to 4 and the capacitance of the capacitors at a scan rate of 1, 2, 5, 10, 50 and 100 mV / (specific capacitance).

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.

Hereinafter, the term " heterogeneous material " refers to an element that is artificially introduced onto the surface of activated carbon in addition to carbon (C), which is a component of activated carbon.

According to IUPAC (International Union of Pure and Applied Chemistry) definition, the pore size of the porous body is divided into three types according to the pore diameter of the porous material. The micropore has a pore diameter of 2 nm or less, the mesopore has a pore diameter of 2 To 50 nm, and a macropore is defined as 50 nm or more. Hereinafter, the micropore means that the pore diameter is 2 nm or less according to IUPAC, the mesopore means that the pore diameter is 2 to 50 nm according to IUPAC, and the macropore has a pore diameter of 50 nm or more according to IUPAC It is used as meaning.

The activated carbon for a supercapacitor electrode according to a preferred embodiment of the present invention is characterized in that the surface thereof is doped with at least one different element selected from phosphorus (P), boron (B) and fluorine (F) And the heterogeneous element have a weight ratio of 1: 0.005 to 0.05, and a specific surface area of 1,000 to 3,300 m ² / g.

The activated carbon has a pore volume in the range of 0.70 to 1.30 cm 3 / g, and the activated carbon has micro pores in a range of 70 to 92%, and mesopores and macropores in a range of 8 to 30%.

At least two kinds of different elements selected from phosphorus (P), boron (B) and fluorine (F) may be complexly doped on the surface of the activated carbon.

(A) preparing activated carbon having a specific surface area in the range of 1,000 to 3,300 m ² / g, and (b) reacting phosphorous (P), boron B) and fluorine (F); (c) drying the activated carbon impregnated in the aqueous acid solution; and (c) (d) subjecting the dried resultant to microwave treatment in an inert atmosphere to form carbon (C) doped with at least one hetero element selected from phosphorus (P), boron (B) and fluorine (F) The heterogeneous element includes the steps of obtaining activated carbon having a weight ratio of 1: 0.005 to 0.05.

Hereinafter, a method of manufacturing activated carbon for a supercapacitor electrode according to a preferred embodiment of the present invention will be described in more detail.

Prepare activated carbon having a specific surface area in the range of 1,000-3,300 m ² / g.

The activated carbon is impregnated with an aqueous acid solution containing at least one kind of element selected from phosphorus (P), boron (B) and fluorine (F).

The acid aqueous solution may be at least one selected from the group consisting of an aqueous solution of phosphoric acid (H ₃ PO ₄ ), an aqueous solution of boric acid (H ₃ BO ₃ ) and an aqueous solution of hydrofluoric acid (HF) Is preferably used.

The acid aqueous solution may be a mixed acid aqueous solution of at least two selected from the group consisting of an aqueous solution of phosphoric acid (H ₃ PO ₄ ), an aqueous solution of boric acid (H ₃ BO ₃ ) and a solution of hydrofluoric acid (HF) An aqueous acid solution may be used. In this case, the surface of the activated carbon is doped with at least two kinds of hetero elements selected from phosphorus (P), boron (B) and fluorine (F).

The activated carbon impregnated in the acid aqueous solution is dried. The drying may be naturally dried or a drying apparatus such as an oven may be used. The drying is preferably performed at a temperature of about room temperature to about 100 ° C for about 10 minutes to about 48 hours.

The dried product (activated carbon) is subjected to microwave treatment in an inert atmosphere to form a mixture of carbon (C), which is doped with one or more hetero-elements selected from phosphorus (P), boron (B) and fluorine (F) The heterogeneous element obtains activated carbon having a weight ratio of 1: 0.005 to 0.05.

The microwave treatment preferably uses an output of 100 to 1,500 W, and the inert atmosphere may be an argon (Ar) or nitrogen (N ₂ ) gas atmosphere.

As a means for heating or drying the material, fire, hot air, steam, infrared rays by heat transfer, etc. are used. These are called external heating by heating the surface of the object by applying heat from the outside of the object and slowly heating the object by the heat conduction of the object.

On the other hand, in the dielectric heating using an electric field having a high frequency and the microwave heating using an electromagnetic wave of a higher frequency, the object to be heated becomes a heating element and is called internal heating because heating is performed inside the material. In the case of such internal heating, there is almost no extra heat scattering from the outside of the object, so that it is possible to perform heating with high efficiency in principle.

The microwave has a wavelength ranging from 1 mm to 100 cm and belongs to a class of waves having a short wavelength among the waves used as radio waves.

In the case of external heating, heat is generated from an external heat source and is conducted or radiated to the object to be heated. However, when a microwave is used, the object to be heated is heated and heated. Also, since the object to be heated reacts with the microwave to generate internal and volumetric heating, the temperature gradient and the heat flow inside the object to be heated are opposite to the external heating. These properties make it possible to dry very quickly and uniformly, and to reduce thermal stress and prevent cracking.

The microwave generator includes a magnetron generating a microwave, a guide tube for moving the microwave to one side, a waveguide having a slot for distributing the wavelength of the microwave through the guide tube evenly, and transmission.

In microwave heating, the object to be heated becomes a heating element, which is heated inside the material. In the case of such microwave heating, there is almost no extra heat scattered from the outside of the object to be heated. .

The microwave treatment is based on the heating principle of the microwave and uses the microwave energy as a heat source to heat the dried activated carbon. A microwave is generated by using a microwave generator, and the activated carbon is heated using an oscillated microwave.

The microwave treatment is preferably performed for 10 to 120 seconds.

After the microwave treatment, the surface is doped with at least one kind of heterogeneous element selected from phosphorus (P), boron (B) and fluorine (F), the carbon (C) constituting the element and the dissimilar element are mixed at a ratio of 1: 0.005 to 0.05 Of activated carbon can be obtained. Even if a hetero element is introduced on the surface of activated carbon, it does not affect the carbon structure or pore structure inside activated carbon.

The activated carbon doped with the hetero-element has a pore volume ranging from 0.70 to 1.30 cm 3 / g, a micro pore ranging from 70 to 92%, and a mesopore and macro pore ranging from 8 to 30%.

One or more heteroatoms selected from the group consisting of phosphorus (P), boron (B) and fluorine (F) doped on the surface of the activated carbon are functional groups such as hydrogen (H), oxygen (O), sulfur (S) (C) and boron (B) form a covalent bond, or carbon (C) and fluorine (F) form a covalent bond on the surface of activated carbon, Thereby forming a covalent bond. The C-P covalent bond, C-B covalent bond or C-F covalent bond remains stable under severe electrochemical conditions and at high temperatures.

The surface of the activated carbon doped with at least one heteroatom selected from phosphorus (P), boron (B) and fluorine (F) maintains hydrophobicity and has an excellent affinity with an organic solvent. It is possible to improve the energy density of the supercapacitor by improving penetration into the inside.

Hereinafter, a method of manufacturing the supercapacitor electrode using the above-described activated carbon for supercapacitor electrode will be described.

 A composition for electrodes is prepared by mixing activated carbon for a supercapacitor electrode, a conductive material, a binder and a solvent, each of which contains a heteroelement on its surface.

Wherein the composition for the electrode comprises 2 to 20 parts by weight of the conductive material for 100 parts by weight of the activated carbon for the supercapacitor electrode, 2 to 20 parts by weight of the conductive material for the supercapacitor electrode, To 100 parts by weight of the activated carbon for the supercapacitor electrode, and 100 to 300 parts by weight of the solvent. When the electrode composition is agitated for a predetermined time (for example, 10 minutes to 12 hours) using a mixer such as a planetary mixer, it is difficult to uniformly mix (completely disperse) A composition for an electrode suitable for production can be obtained. A mixer such as a planetary mixer enables the preparation of compositions for uniformly mixed electrodes.

The binder may be selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidenefluoride (PVDF), carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), polyvinyl butyral vinyl butyral (PVB), poly-N-vinylpyrrolidone (PVP), styrene butadiene rubber (SBR), polyamide-imide, polyimide One or more selected ones may be used in combination.

The conductive material is not particularly limited as long as it is an electron conductive material which does not cause a chemical change. Examples of the conductive material include natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, Super-P black, carbon fiber, , Metal powder such as aluminum and silver, or metal fiber.

The solvent may be an organic solvent such as ethanol (EtOH), acetone, isopropyl alcohol, N-methyl pyrrolidone (NMP), propylene glycol (PG) or water.

A composition for an electrode in which activated carbon for a supercapacitor electrode is mixed with a binder, a conductive material and a solvent is formed into an electrode form, or the electrode composition is coated on a metal foil to form an electrode, The electrode is formed in a sheet state by attaching it to a metal foil, and the resultant is dried at a temperature of 100 to 350 DEG C to form an electrode.

More specifically explaining an example of forming the electrode, the electrode composition can be pressed and formed by using a roll press molding machine. The roll press molding machine aims at improving the electrode density through rolling and controlling the thickness of the electrode. The roll press molding machine includes a controller capable of controlling the thickness and the heating temperature of the rolls and rolls at the upper and lower ends, the winding ≪ / 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 5 to 20 ton / cm 2, and the roll temperature is preferably 0 to 150 ° C. The composition for the electrode which has undergone the above press-bonding process is subjected to a drying process. The drying process is carried out at a temperature of 100 ° C to 350 ° C, preferably 150 ° C to 300 ° C. If the drying temperature is less than 100 ° C, evaporation of the solvent is difficult, which is not preferable, and oxidation of the conductive material may occur during drying at a high temperature exceeding 350 ° C, which is not preferable. Therefore, the drying temperature is preferably 100 占 폚 or more and not exceeding 350 占 폚. The drying process is preferably carried out at the above temperature for about 10 minutes to 6 hours. Such a drying process improves the strength of the electrode by drying the dried composition for electrode (solvent evaporation) and binding powder particles.

In another example of forming the electrode, the composition for the electrode may be formed using a metal foil such as a Ti foil, an Al foil, an Al etching foil, or a Cu foil metal foil), or the electrode composition may be formed into a sheet state (rubber type) by pressing the electrode composition with a roller and then attached to a metal foil to form an electrode shape. The aluminum etched foil means that the aluminum foil is etched in a concavo-convex shape. The electrode shape after the above-described process is subjected to a drying process. The drying process is carried out at a temperature of 100 ° C to 350 ° C, preferably 150 ° C to 300 ° C. If the drying temperature is less than 100 ° C, evaporation of the solvent is difficult, which is not preferable, and oxidation of the conductive material may occur during drying at a high temperature exceeding 350 ° C, which is not preferable. Therefore, the drying temperature is preferably 100 占 폚 or more and not exceeding 350 占 폚. The drying process is preferably carried out at the above temperature for about 10 minutes to 6 hours. Such a drying process improves the strength of the electrode by drying the composition for electrode (solvent evaporation) and binding the powder particles.

The super capacitor electrode manufactured as described above can be applied to a small coin type super capacitor as shown in FIG. 1 as a high capacity, a wound type super capacitor as shown in FIGS. 2 to 5, and the like.

Hereinafter, a method of manufacturing a coin-type supercapacitor will be described with reference to FIG.

FIG. 1 is a sectional view of a coin-type supercapacitor to which the supercapacitor electrode 10 is applied, according to a state of use of the supercapacitor electrode according to the present invention. In FIG. 1, reference numeral 50 denotes a metal cap as a conductor, reference numeral 60 denotes a porous separator for preventing insulation and short circuit between the supercapacitor electrodes 10, reference numeral 70 denotes an electrolyte solution preventing leakage of the electrolyte solution It is a gasket for insulation and short circuit protection. At this time, the supercapacitor electrode 10 is firmly fixed to the metal cap 50 by an adhesive.

The coin type supercapacitor includes a positive electrode made of the above-described supercapacitor electrode, a negative electrode made of the above-described supercapacitor electrode, a separator disposed between the positive electrode and the negative electrode, Is placed in a metal cap, and an electrolyte solution in which an electrolyte is dissolved is injected between the anode and the cathode, followed by sealing with a gasket.

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.

Hereinafter, a method of manufacturing a wound-type supercapacitor will be described with reference to FIGS. 2 to 5. FIG. 2 to 5 are views showing a winding type super capacitor.

As shown in FIG. 2, the lead wires 130 and 140 are attached to the positive electrode 120 and the negative electrode 110, respectively, which are formed of supercapacitor electrodes.

3, the first separator 150, the anode 120, the second separator 160, and the working electrode 110 are laminated and coiled to form a roll- (175), and wound around the roll with an adhesive tape (170) or the like so that the roll shape can be maintained.

The second separator 160 between the anode 120 and the cathode 110 prevents shorting between the anode 120 and the cathode 110. The first and second separation membranes 150 and 160 may be formed of any one of 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, Or a separator commonly used in the field of batteries and capacitors such as rayon fibers.

As shown in Fig. 4, a sealing rubber 180 is mounted on a roll-shaped product and is mounted on a metal cap 190 (e.g., an aluminum case).

The electrolytic solution is injected so that the rolled element 175 and the lithium foil 195 are impregnated and sealed.

Hereinafter, embodiments according to the present invention will be specifically shown, and the present invention is not limited to the following embodiments.

≪ Example 1 >

MSP20 (Kansai Coke & Chemicals Co.), a pulmonary activated carbon, was used as an electrode active material.

3 g of MSP20 was immersed in 300 cc of a 1 M hydrofluoric acid (HF) aqueous solution and mixed for 18 hours, followed by drying at 90 캜 for 12 hours or more.

The dried resultant was subjected to microwave treatment in an argon atmosphere for 20 seconds to produce activated carbon for supercapacitor electrode containing fluorine (F) on the surface. The frequency used for the microwave treatment was 2450 MHz and the output was 400 W.

≪ Example 2 >

Activated carbon for the supercapacitor electrode containing fluorine (F) on the surface was prepared in the same manner as in Example 1, except that a 10M aqueous solution of hydrofluoric acid (HF) was used instead of the 1M hydrofluoric acid (HF) aqueous solution.

≪ Example 3 >

Activated carbon for a supercapacitor electrode containing boron (B) on its surface was prepared in the same manner as in Example 1, except that 1 M boric acid (H ₃ BO ₃ ) aqueous solution was used instead of the hydrofluoric acid (HF) aqueous solution.

<Example 4>

Activated carbon for phosphorus (P) containing phosphorus on the surface was prepared in the same manner as in Example 1, except that 1 M phosphoric acid (H ₃ PO ₄ ) aqueous solution was used instead of hydrofluoric acid (HF) aqueous solution.

&Lt; Comparative Example 1 &

MSP20 (Kansai Coke & Chemicals Co.), which is an activated carbon electrode active material, was used as the activated carbon for the supercapacitor electrode of Comparative Example 1.

X-ray photoelectron spectroscopy (X) was conducted to determine the introduction of fluorine (F), the content of fluorine (F), and the ratio of the hetero atoms to carbon in activated carbon for the super capacitor electrode synthesized according to Example 1 and Example 2, -ray photoelectron spectroscopy (hereinafter referred to as &quot; XPS &quot;) is shown in Table 1 and FIG. 6 below.

division Carbon (C) content
(weight %) Oxygen (O) content
(weight %) Fluorine (F) content
(weight %) Fluorine (F) / carbon (C) Comparative Example 1 92.3 7.7 Example 1 91.7 7.6 0.7 0.0076 Example 2 86.1 10.6 3.3 0.0383

The results of analysis by XPS to determine the introduction of boron (B), the content of boron (B), and the ratio of the hetero atoms to the carbon in the activated carbon for the super capacitor electrode synthesized according to Example 3 are shown in the following Table 2 7.

division Carbon (C) content
(weight %) Oxygen (O) content
(weight %) Fluorine (B) content
(weight %) Boron (B) / carbon (C) Comparative Example 1 92.3 7.7 Example 3 84.9 11.9 3.1 0.0365

The results of analysis by XPS to determine the presence of phosphorus (P), the content of phosphorus (P), and the ratio of the different elements to carbon in the activated carbon for the super capacitor electrode synthesized according to Example 4 are shown in the following Table 3 8.

division Carbon (C) content
(weight %) Oxygen (O) content
(weight %) Phosphorus (P) content
(weight %) Phosphorus (P) / carbon (C) Comparative Example 1 92.3 7.7 Example 3 85.2 13.4 1.3 0.0153

It is judged that the heterogeneous element is introduced without affecting the pore characteristics of the activated carbon for the supercapacitor electrode.

division Specific surface area
(m ² / g) Pore volume
(cm &lt; ³ &gt; / g)  Pore fraction (%) The micro- Meso and macro. Comparative Example 1 2379 1.01 90.0 10.0 Example 1 2313 0.99 89.9 10.1 Example 2 2120 0.91 88.0 12.0 Example 3 2297 0.95 89.1 10.9 Example 4 2301 0.97 89.6 10.4

The specific capacitance was measured by the cyclic voltammetry test and the scan rate was 1, 2, 5, 10, 50 and 100 mV / s in the range of 0 ~ 2.7V. 9.

Referring to FIG. 9, not only the discharge capacity increase but also the rate characteristic are improved. This is because the microporosity structure is maintained while the heterogeneous element is introduced, and the conductivity is improved by bonding at the surface of activated carbon.

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, but, on the contrary, This is possible.

10: super capacitor electrode 50: metal cap
60: Membrane 70: Gasket
110: working electrode 120: positive electrode
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

Claims (8)

delete delete delete (a) preparing activated carbon having a specific surface area in the range of 1,000 to 3,300 m ² / g;
(b) impregnating the activated carbon with an acid aqueous solution containing at least one heteroatom selected from phosphorus (P), boron (B) and fluorine (F);
(c) drying the activated carbon impregnated in the aqueous acid solution;
(d) subjecting the dried resultant to microwave treatment in an inert atmosphere to form carbon (C) doped with at least one hetero element selected from phosphorus (P), boron (B) and fluorine (F) The heterogeneous element comprises a step of obtaining activated carbon having a weight ratio of 1: 0.005 to 0.05,
The acid aqueous solution may be one or more selected from the group consisting of aqueous solutions of phosphoric acid (H ₃ PO ₄ ), boric acid (H ₃ BO ₃ ) and hydrofluoric acid (HF) Wherein the carbon nanotubes are used as the carbon nanotubes.
The method of claim 4, wherein the activated carbon doped with the hetero-element has a pore volume in the range of 0.70 to 1.30 cm 3 / g, a micropore in a range of 70 to 92%, a mesopore and macropores in a range of 8 to 30% Wherein the carbon nanotubes are formed on the surface of the supercapacitor electrode.
delete (a) preparing activated carbon having a specific surface area in the range of 1,000 to 3,300 m ² / g;
(b) impregnating the activated carbon with an acid aqueous solution containing at least one heteroatom selected from phosphorus (P), boron (B) and fluorine (F);
(c) drying the activated carbon impregnated in the aqueous acid solution;
(d) subjecting the dried resultant to microwave treatment in an inert atmosphere to form carbon (C) doped with at least one hetero element selected from phosphorus (P), boron (B) and fluorine (F) The heterogeneous element comprises a step of obtaining activated carbon having a weight ratio of 1: 0.005 to 0.05,
The acid aqueous solution is prepared by using at least two mixed acid aqueous solutions selected from an aqueous solution of phosphoric acid (H ₃ PO ₄ ), a solution of boric acid (H ₃ BO ₃ ) and a solution of hydrofluoric acid (HF) Wherein the activated carbon in the step (d) is a mixture of at least two kinds of different elements selected from phosphorus (P), boron (B) and fluorine (F) Gt;
5. The method for producing activated carbon for a supercapacitor electrode according to claim 4, wherein the microwave treatment uses an output of 100 to 1,500 W, and the inert atmosphere is an atmosphere of argon (Ar) or nitrogen (N ₂ ) gas .

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