WO2016171407A1 - Supercapacitor and manufacturing method therefor - Google Patents

Abstract

A supercapacitor comprises: current collectors provided to be spaced apart so as to face each other; an organic electrolyte layer interposed between the current collectors; a separation film dividing the organic electrolyte layers so as to prevent electrical shorts between the current collectors; and a carbon nano thin film made of carbon nano materials aligned on an upper surface of each of the current collectors in a direction substantially parallel to the upper surface. Therefore, an alternating current line filtering element with improved energy density per volume and frequency response speed in a state in which an operating voltage is expanded to 2.5V can be implemented.

Description

Supercapacitors and manufacturing methods thereof

The present invention relates to a supercapacitor and a method of manufacturing the same, and more particularly, to a supercapacitor that can be used as an AC line filtering element and a method of manufacturing the supercapacitor.

Among the components constituting the AC line filtering element is an aluminum electrolytic capacitor. In particular, the aluminum electrolytic capacitor occupies the largest volume of the components. In addition, the aluminum electrolytic capacitor applied to the AC line filtering device requires a high energy density per unit volume. Therefore, miniaturization of an aluminum electrolytic capacitor, which occupies a relatively large volume among components constituting the AC line filtering element, is required.

On the other hand, supercapacitors, or electric double layer capacitors (EDLC) have a higher energy density per volume than aluminum electrolytic capacitors. The supercapacitor is considered as a substitute to replace the aluminum electrolytic capacitor.

However, typical electric double layer capacitors are difficult to apply as components of AC line filtering devices because of their very slow frequency response. That is, a general electric double layer capacitor uses activated carbon as an electrode material, but the complex and narrow pore structure restricts the movement of electrolyte ions, thereby reducing the frequency response characteristic speed.

Prior art related to the supercapacitor is Korean Patent Publication No. 10-2014-0011485 (published date: 2014.01.29.).

One object of the present invention is to provide a supercapacitor having an improved response speed and energy density per unit volume and an increased operating voltage range.

One object of the present invention is to provide a method of manufacturing the supercapacitor.

Supercapacitors according to embodiments of the present invention, the current collectors provided to face each other spaced apart, the organic electrolyte layer interposed between the current collector, the organic electrolyte layer partitions the electrical between the current collector And a carbon nano thin film made of a carbon nano material aligned in a direction substantially parallel to the upper surface on a separator for suppressing a short circuit and on an upper surface of each of the current collectors.

In one embodiment of the present invention, the carbon nanomaterial may include carbon nanotubes or graphene.

In one embodiment of the present invention, the carbon nano thin film may have a pore structure having a thickness in the range of 50 to 300 nm and a pore size distribution in the range of 2 to 50 nm.

In one embodiment of the present invention, the current collector may have a laminated structure in which a titanium thin film and a gold thin film are sequentially stacked between aluminum foils.

In one embodiment of the present invention, the organic electrolyte layer may include an alkyl salt and an ACN organic solvent.

In the method of manufacturing a supercapacitor according to embodiments of the present invention, after preparing current collectors, carbon nanomaterials are arranged on a top surface of each of the current collectors in a direction substantially parallel to the top surface. Each of the carbon nano thin films is formed. After arranging the current collectors to face each other, an organic electrolyte layer and the organic electrolyte layer are partitioned between the current collectors to form a separator for suppressing a short circuit between the current collectors.

In one embodiment of the present invention, in order to form the carbon nano thin film, after dispersing the carbon nanomaterial in a solution to form a dispersion, the dispersion is formed on the template through a vacuum filtration process on the template. The template on which the carbon nanofilm is formed is suspended on a basic solution to remove the template and leave the carbon nanofilm. Thereafter, the basic solution is diluted and converted into a neutral solution, and then each of the current collectors in which a thin gold film is formed on an aluminum foil is immersed in the neutral solution. Thereafter, the neutral solution is removed while each of the current collectors is immersed to form a carbon nano thin film on the gold thin film.

Here, the dispersion may be formed using an ultrasonic mill without a dispersion.

In one embodiment of the present invention, in order to form each of the current collector, the aluminum foil may be surface-etched, and a titanium thin film and a gold thin film may be sequentially formed on the surface-etched aluminum foil.

Here, the gold thin film and the titanium thin film may be formed through an electron beam vacuum deposition process.

The supercapacitor according to the embodiments of the present invention as described above may include an carbon nano thin film and an organic electrolyte layer, thereby increasing energy density per volume and improving frequency response characteristics. In addition, the thickness of the carbon nano thin film can be adjusted according to the maximum capacitance or energy density per volume applicable to the AC line filtering. That is, as the supercapacitor has an increased capacitance per volume and an operating voltage range, an energy density per volume may be 100 to 1000 times higher than that of a conventional supercapacitor.

On the other hand, since the pore structure of the carbon nano thin film is suitable for the organic electrolyte, the driving voltage can be extended to 2.5V. When the supercapacitor is applied to a low voltage AC line filtering element of 21 V or less, the capacitance per volume is higher than that of a conventional aluminum electrolytic capacitor.

1 is a schematic diagram showing the electrode density and frequency response characteristics of the supercapacitor according to the alignment direction and thickness of the carbon nanomaterial in the carbon nanotube (CNT) film formed on the substrate.

2 is a photograph for explaining a process of forming a carbon nanotube thin film on a current collector according to an embodiment of the present invention.

3 is electron micrographs showing a surface where a carbon nanotube thin film (electrode) is formed on a current collector.

4 is a graph for explaining the relationship between the electrode thickness and the carbon mass of the carbon nanotube supercapacitor (Example).

5 to 8 are graphs for explaining the frequency response characteristics according to the electrode thickness of the carbon nanotube supercapacitor (Example).

9 is a graph showing a board diagram of a carbon nanotube supercapacitor (Example) and an aluminum electrolytic capacitor (Comparative Example 1).

10 is a carbon nanotube supercapacitor (example) including a current collector in which a titanium thin film and a gold thin film are sequentially stacked on an aluminum foil, and a supercapacitor (comparative example 2) formed by using an aluminum foil as a current collector. This is a board diagram showing the phase angle.

11 to 14 are graphs for explaining the electrochemical behavior of the carbon nanotube supercapacitor (thickness of the carbon nanotube thin film = 298 nm).

15 is a graph showing the pore size distribution of carbon nanotube powder.

FIG. 16 is a graph illustrating a change in capacitance per volume according to cell voltages of a carbon nanotube supercapacitor (example) and an aluminum electrolytic capacitor.

Supercapacitors according to embodiments of the present invention, the current collectors provided to face each other spaced apart, the organic electrolyte layer interposed between the current collector, the organic electrolyte layer partitions the electrical between the current collector And a carbon nano thin film made of a carbon nano material aligned in a direction substantially parallel to the upper surface on a separator for suppressing a short circuit and on an upper surface of each of the current collectors.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In the accompanying drawings, the size and amount of the objects are shown to be enlarged or reduced than actual for clarity of the invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "include" are intended to indicate that there is a feature, step, function, component, or combination thereof described on the specification, and other features, steps, functions, components Or it does not exclude in advance the possibility of the presence or addition of them in combination.

On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Supercapacitor

A supercapacitor according to embodiments of the present invention includes current collectors, carbon nano thin films, separators, and organic electrolyte layers. The supercapacitor may have a form of a cylinder type or a plate type.

The current collectors are provided to face each other apart from each other. The current collectors may apply a voltage to ions dissociated in the organic electrolyte layer.

Each of the current collectors may have a laminated structure in which a titanium thin film and an Au thin film are sequentially stacked on an aluminum foil. The gold element included in the gold thin film is a material that forms an excellent electrical contact with the carbon nano thin film. Thus, as the gold thin film is formed, electrical contact between the carbon nano thin film and the aluminum foil may be improved. That is, depending on the type of metal in contact with the carbon nano thin film such as carbon nanotubes or graphene, the metal wettablity and Schottky barrier height, and also the interface and device characteristics may be affected. Considering that the gold thin film may be additionally formed.

Meanwhile, a titanium thin film may be used as an adhesion layer between the gold thin film and the aluminum foil.

The organic electrolyte layer is interposed between the current collectors. The organic electrolyte layer is made of an organic electrolyte material. The organic electrolyte material replaces the existing aqueous electrolyte material so that the supercapacitor can have an extended operating voltage range. For example, the supercapacitor made of the aqueous electrolyte material has an operating range of about 1.23 V, whereas in the case of the supercapacitor including the organic electrolyte layer and the carbon nano thin film, ions dissociated from the organic electrolyte layer have a pore structure. By having suitable accessibility to the carbon nano thin film having a can have an increased operating voltage range. For example, the supercapacitor including the organic electrolyte layer and the carbon nano thin film may have an operating voltage range of up to 2.5V.

The organic electrolyte layer may be formed of an alkyl salt and an ACN organic solvent. For example, the alkyl salt may include tetraethylammonium, tetrabutylammonium or tetramethylammonium as a cation. In particular, examples of the alkyl salt include tetraethylammonium tetrafluoroborate (TEABF ₄ ).

The separator is provided in the organic electrolyte layer. The separator partitions the organic electrolyte layer. The separator may suppress electrical short between the current collectors.

The carbon nano thin film is formed on an upper surface of each of the current collectors. The carbon nano thin film is made of carbon nano material aligned in a direction substantially parallel to the upper surface of the current collectors. The carbon nano thin film functions as an electrode of a supercapacitor.

When the carbon nanomaterial is aligned in a direction perpendicular to the upper surface (see FIG. 1A), the carbon nanomaterial may have a macroporous pore structure. In this case, the response speed is high, but since the pore size of 50 nm or more is formed, the energy density per volume may be low.

On the other hand, as the carbon nano thin film is aligned in a direction substantially parallel to the upper surface, the pore size may be reduced. As a result, the energy density per volume may be increased while the response speed may be reduced (see FIG. 1B).

Thus, the carbon nano thin film may have a thickness in the range of 50 to 300 nm. As a result, the carbon nano thin film may have an improved energy density per volume and response speed. In this case, the carbon nano thin film may have a pore structure having a pore size distribution in the range of 2 to 50 nm.

Meanwhile, the carbon nanomaterial may include carbon nanotubes or graphene.

For example, the carbon nanotubes may include single-walled carbon nanotubes, double-walled carbon nanotubes, multiwalled carbon nanotubes, thin multiwalled carbon nanotubes, and bundle carbon nanotubes.

Manufacturing method of supercapacitor

2 is a photograph for explaining a process of forming a carbon nanotube thin film on a current collector according to an embodiment of the present invention.

Referring to FIG. 2, in the method of manufacturing a supercapacitor according to embodiments of the present invention, first, current collectors are prepared. The current collector may be formed using a metal material. When the current collector has a multilayer structure, the current collector may be formed by sequentially forming a titanium thin film and a gold thin film on an aluminum foil.

More specifically, after the aluminum foil is prepared, the surface of the aluminum foil is etched to treat the surface of the aluminum foil. This may increase the surface roughness of the surface of the aluminum foil to increase the bonding strength with the carbon nano thin film formed subsequently.

Thereafter, a titanium thin film and a gold thin film are sequentially formed on the surface-treated aluminum foil. The titanium thin film and the gold thin film may be formed through an electron beam vacuum deposition process. As a result, a current collector in which a titanium thin film and a gold thin film are sequentially formed is formed on the aluminum foil. The gold thin film may be improved in electrical contact properties by contact with a subsequently formed carbon nano thin film.

Subsequently, each of the carbon nano thin films made of carbon nanomaterials aligned in a direction substantially parallel to the upper surface is formed on the upper surface of each of the current collectors.

In order to form the carbon nano thin film, first, the carbon nanomaterial is dispersed in a solution to form a dispersion. For example, carbon nanotubes may be used as the carbon nanomaterial. The solution may be made of a propylene carbonate material. In this case, the dispersion may be formed using an ultrasonic grinder without a separate dispersion. (See FIG. 2A)

The dispersion is then formed on a template through a vacuum filtration process to form a carbon nanofilm. That is, the dispersion is poured onto the template and the carbon nanomaterials contained in the dispersion are coated on the template surface through a vacuum filtration process. As a result, a carbon nanofilm is uniformly formed on the template. In this case, the template may be formed using a material and the ennodic aluminum oxide. (See Figure 2 (b))

The template on which the carbon nanofilm is formed is then suspended on a basic solution such as sodium hydroxide solution to remove the template and leave the carbon nanofilm in the basic solution. (See Figure 2 (c))

Thereafter, deionized water is added to the basic solution to dilute the basic solution to convert the basic solution into a neutral solution. Thereafter, the neutral solution is removed while the aluminum foil in which the titanium thin film and the gold thin film are sequentially formed in the neutral solution is removed to form a carbon nano thin film on the aluminum foil including the gold thin film. (See FIG. 2 (d).)

The collectors on which the carbon nano thin films are formed are disposed to face each other. At this time, the supercapacitor may have a cylindrical shape or a plate shape according to the arrangement.

Subsequently, an organic electrolyte layer and the organic electrolyte layer are partitioned between the current collectors to form a separator to suppress a short circuit between the current collectors, thereby manufacturing a supercapacitor.

The organic electrolyte layer may be formed using an organic electrolyte including an alkyl salt and an ACN organic solvent. For example, the alkyl salt may include tetraethylammonium, tetrabutylammonium or tetramethylammonium as a cation. In particular, examples of the alkyl salt include tetraethylammonium tetrafluoroborate (TEABF ₄ ).

When the carbon nano thin film is formed on the current collector through the vacuum filtration process as described above, a plasma enhanced chemical vapor deposition (PECVD) process for manufacturing graphene and carbon nanotubes aligned in a conventional vertical direction or Compared to a thermal CVD process, the simplicity can improve the economics. Furthermore, the thickness of the carbon nano thin film may be adjusted by controlling the amount of carbon nano material included in the dispersion.

In addition, in the supercapacitor including the organic electrolyte layer and the carbon nano thin film, the ions dissociated from the organic electrolyte layer may have an increased operating voltage range by having a suitable accessibility to the carbon nano thin film having a pore structure. . For example, the supercapacitor including the organic electrolyte layer and the carbon nano thin film may have an operating voltage range up to 2.5V.

Production Example Carbon nano  Preparation of the tube film

2 mg of single-walled carbon nanotubes (SWCNTs) were dispersed in 20 mL of propylene carbonate for 20 minutes using an ultrasonic mill. A predetermined amount of the prepared carbon nanotube solution was diluted in methanol and dispersed for 3 minutes using an ultrasonic mill. Thereafter, the diluted carbon nanotube solution was coated on an enodic aluminum oxide template (AAO) by vacuum filtration. When the AAO template coated with the carbon nanotube film was floated on the sodium hydroxide (NaOH) solution, the AAO template was dissolved and the carbon nanotube film remained. Deionized water was added to form a neutral solution until the sodium hydroxide solution became neutral (pH 7). Subsequently, when the aluminum current collector in which the gold / titanium thin film was deposited on the aluminum foil in the neutral solution was settled and the neutral solution was removed, the carbon nanotube film remaining in the neutral solution was formed as an electrode on the aluminum current collector. On the other hand, the thickness of the carbon nanotube film functioning as an electrode was adjusted from 53 nm to 298 nm, respectively.

Example  Fabrication of Carbon Nanotube Supercapacitors

A supercapacitor was manufactured using a two-electrode carbon nanotube electrode / current collector, an organic electrolyte layer, and a separator formed in the above-described preparation example in a glove box. The organic electrolyte was used by dissolving 1M tetraethylammonium tetrafluoroborate (TEABF ₄ ) in acetonitrile. Polytetrafluoroethylene (PTFE) was used as the separator.

Experimental Example  1. Characterization

The shape and thickness of the carbon nanotube films were analyzed by electron scanning microscope (SEM) and atomic force microscope (AFM). The specific surface area and pore size distribution of carbon nanotube powders are obtained through Brunauer-Emmett-Teller (BET) and Barrett-Joiner-Hilda (BJH).

Experimental Example  2. Measurement of electrochemical properties

Cyclic voltammetry, constant current charge and discharge, and electrochemical impedance spectroscopy are performed. The frequency response is driven by a direct current of 0 V and an alternating current of 10 mV. All electrochemical measurements are made with a two-electrode system. Electrochemical measurements of aluminum electrolytic capacitors are made for comparison with carbon nanotube supercapacitors.

3 is electron micrographs showing the surface of the carbon nanotube thin film formed on the current collector.

3 (a) and 3 (b) are low and high magnification scanning electron micrographs of a carbon nanotube film coated on a current collector including gold / titanium / aluminum foil.

In FIG. 3A, the dark areas are pores generated during the etching process to expand the surface area of the aluminum foil. These pores range in size from several nm to several tens of μm. It can be seen that the carbon nanotube film covers the entire surface of the metal current collector by covering the pores of the aluminum foil.

A cross section of a very thin carbon nanotube is shown on the etched aluminum foil in FIG. The thickness of the carbon nanotube film was prepared from 53 to 298 nm, which corresponds to a mass of 4 to 32 μg of carbon nanotube film. (See Figure 4)

As the thickness of the carbon nanotube film increases, the density of the carbon nanotube increases from 0.75 g / cc to 1.08 g / cc. This corresponds to 48.7% to 70.1% of theoretical density (1.54 g / cc) when the diameter of single-walled carbon nanotubes is 1 nm.

5 to 8 are graphs for explaining the frequency response characteristics according to the electrode thickness of the carbon nanotube supercapacitor (Example). 9 is a graph showing a board diagram of a carbon nanotube supercapacitor (Example) and an aluminum electrolytic capacitor (Comparative Example 1).

5 to 9, the organic electrolyte and the carbon nanotube supercapacitors have a frequency response characteristic fast enough for an AC line filtering application.

As shown in FIG. 5, the 120 Hz phase angle of the supercapacitor having a thickness of 53 nm to 298 nm ranges from -82.2 ° to -84.3 °.

This characteristic is similar to that of a commercial aluminum electrolytic capacitor (Comparative Example 1) with a 120 Hz phase angle of -82 °. (See FIG. 9)

Referring to FIG. 6, the Nyquist plot shows nearly vertical behavior and low equivalent series resistance (0.22 to 0.26 Ω), which means that all supercapacitors exhibit capacitor behavior. The absence of a semicircle and a -45 ° line in the high frequency region means physical adsorption and desorption of ions with very fast charge storage. The pore structure of the carbon nanotube film contributes to the rapid movement of electrolyte ions.

On the other hand, the frequency response characteristic and capacitance per area of the supercapacitor vary with the electrode thickness. As the electrode thickness decreases, the response speed increases, but the capacitance decreases.

In the balance between the response speed and the capacitance, an appropriate thickness capable of maintaining the maximum capacitance while maintaining a high phase angle (<-80 °, 120 Hz) is important (see FIG. 7). That is, as the thickness of the carbon nanotube film is increased from 53 to 298 nm, the capacitance increases about 58 times from 58 to 282 μF / cm ² .

Referring to FIG. 8, as the thickness of the carbon nanotube film is increased from 53 to 298 nm, the time constant increases from 60 to 500 μs. This is because the time constant increases because the pore structure, which is the distance required to move the electrolyte ions during charge and discharge, increases as the electrode thickness increases. Supercapacitors with relatively short time constants can serve as sufficient AC line filtering at 120 Hz.

10 is a phase angle of a carbon nanotube supercapacitor (example) including a current collector in which a titanium thin film and a gold thin film are sequentially formed on an aluminum foil and a supercapacitor (comparative example 2) using an aluminum foil as a metal current collector. This is a board diagram showing.

Referring to FIG. 10, an aluminum current collector may additionally deposit a gold thin film in contact with the carbon nanotube thin film, thereby exhibiting a very high frequency response even when an organic electrolyte is used. An aluminum current collector (Comparative Example 2) made of aluminum foil without a gold thin film has a phase angle of approximately -34 ° at 120 Hz, which makes it difficult to use AC line filtering.

Therefore, in order for the supercapacitor to have improved frequency response characteristics, it is possible to further deposit a titanium thin film and a gold thin film on the aluminum foil. In this case, gold (Au) forming the gold thin film forms an improved electrical contact with the carbon nanotubes. Therefore, the electrical contact may be improved as the carbon nanotubes are exposed to the gold thin film.

11 to 14 are graphs for explaining the electrochemical behavior of the carbon nanotube supercapacitor (thickness of the carbon nanotube thin film = 298 nm).

11 to 14, it can be seen that the carbon nanotube supercapacitors have an excellent response speed.

As shown in FIG. 11, the cyclic voltammogram maintains a rectangular shape even at a high scanning speed of 450 V / s (32 μg / cm 2). As the scan rate is increased from 50 to 450 V / s, the capacitance per volume decreases approximately 20% from 10.9 to 8.8 F / cc.

12 shows a nearly linear relationship between current density and scanning speed. In particular, it is shown that there is little variation in the scanning speed of 200 V / s or less.

The constant current charge / discharge curve of FIG. 13 shows a triangular shape and almost no IR drop in a wide current density range.

In Figure 14 the current density is 1 to 20 mA / cm ² It can be seen that the capacitance decreases by about 11% (12.8 ~ 11.5 F / cc) as it increases.

As a result, it can be seen that the carbon nanotube supercapacitor has an improved speed capability with excellent frequency response.

Meanwhile, the carbon nanotube supercapacitor according to the embodiments of the present invention shows the highest energy density per volume (4.11 mWh / cc) among the 120 Hz line filtering supercapacitors developed so far. These results show energy densities that are 100-1000 times higher than previously reported.

This can be obtained through an organic electrolyte layer having a carbon nano thin film of increased density (1.08 g / cc) and an increased operating voltage range (2.5 V).

In addition, graphene and carbon nanotube structures vertically aligned with respect to the current collector surface (see FIG. 1 (a)) exhibit high phase angles from -82 ° to -85 ° at 120 Hz, but have an energy density per volume (0.04 to 0.1 mWh / cc) is low.

On the other hand, supercapacitors made of carbon black or graphene quantum dots also show low energy density of 0.2 to 0.4 mWh / cc and have a low phase angle of -75 ° at 120 Hz.

15 is a graph showing the pore size distribution of carbon nanotube powder.

Referring to FIG. 15, a carbon nanotube supercapacitor according to embodiments of the present invention has improved frequency response. This may be due to the pore structure of the electrode material relatively large compared to the size of the electrolyte ions.

On the other hand, Brunauer-Emmett-Teller (BET) and Barrett-Joiner-Hellenda (BJH) analyzes showed pore distribution of Masophorus (2-50 nm) with an average pore diameter of 6.51 nm. have.

15 shows the pore size distribution of carbon nanotube powder. On the other hand, the sizes of the solvated ions of TEA ⁺ and BF ₄ ⁻ are approximately 1.3 nm and 1.16 nm.

Therefore, due to the pore structure larger than the ionic size of the organic electrolyte, it can be seen that the dissociated ions in the electrolyte have excellent mobility in the macroporous structure of the carbon nanotubes.

FIG. 16 is a graph illustrating a change in capacitance per volume according to cell voltages of a carbon nanotube supercapacitor (example) and an aluminum electrolytic capacitor.

Referring to FIG. 16, the large specific surface area (1125.3 m ² / g) of the carbon nanotubes contributes to the high capacitance of the supercapacitor.

Supercapacitors with carbon nanotubes show a capacitance per volume (25.5 mF / cc to 3.0 mF / cc) at 2.5 V, 8.5 times higher than commercial aluminum electrolytic capacitors (AEC). Connecting a 2.5 V supercapacitor in series or increasing the dielectric layer thickness of an aluminum electrolytic capacitor can increase the operating voltage.

C _{vol of} supercapacitor (∝1 / V ² ) C _vol of this aluminum electrolytic capacitor Because it is reduced more quickly than (∝1 / V ), carbon nanotube supercapacitors have a higher volumetric capacitance up to 21 V than commercial aluminum electrolytic capacitors. Therefore, aluminum electrolytic capacitors could be replaced by low voltage supercapacitors (<21 V). These results were compared by assuming the total thickness of the carbon nanotube supercapacitor to 110 μm in consideration of the volume of all components (electrode, current collector, separator, packaging film).

Such supercapacitors can be usefully used in small electronic devices requiring excellent frequency characteristics.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (10)

Current collectors provided to face each other apart from each other; An organic electrolyte layer interposed between the current collectors; A separator for partitioning the organic electrolyte layer to suppress an electrical short between the current collectors; And And a carbon nano thin film made of carbon nano material aligned in a direction substantially parallel to the upper surface on the upper surface of each of the current collectors. The supercapacitor of claim 1, wherein the carbon nanomaterial comprises carbon nanotubes or graphene. The supercapacitor of claim 1, wherein the carbon nano thin film has a pore structure having a thickness in a range of 50 to 300 nm and a pore size distribution in a range of 2 to 50 nm. The supercapacitor of claim 1, wherein the current collector has a laminated structure in which a titanium thin film and a gold thin film are sequentially stacked on an aluminum foil. The supercapacitor of claim 1, wherein the organic electrolyte layer comprises an alkyl salt and an ACN organic solvent. Preparing current collectors; Forming each of the carbon nano thin films of carbon nanomaterials aligned on a top surface of each of the current collectors in a direction substantially parallel to the top surface; Arranging the current collectors to face each other; And Comprising the organic electrolyte layer and the organic electrolyte layer between the current collector to form a separator for suppressing a short circuit between the current collector, respectively. The method of claim 6, wherein the forming of the carbon nano thin film, Dispersing the carbon nanomaterial in solution to form a dispersion; Forming the carbon nanofilm on the template through the vacuum filtration process; Floating the template in which the carbon nanofilm is formed in a basic solution to remove the template and to leave the carbon nanofilm; Diluting the basic solution to convert it into a neutral solution; Dipping a current collector in which a thin gold film is formed on an aluminum foil in the neutral solution; And Removing the neutral solution while the current collector is immersed to form a carbon nano thin film on the gold thin film. The method of claim 7, wherein the forming of the dispersion is performed using an ultrasonic grinder without a dispersion. The method of claim 6, wherein preparing the current collectors, Surface etching the aluminum foil; And And sequentially forming the titanium thin film and the gold thin film on the surface-etched aluminum foil, respectively. The method of claim 9, wherein the forming of the gold thin film and the titanium thin film, respectively, is performed by an electron beam vacuum deposition process.

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