KR100672372B1 - Energy storage capacitor and method for fabricating the same - Google Patents

Abstract

The present invention provides an energy storage capacitor that can overcome the shortcomings in the current energy storage capacitor and improve its function by newly designing an electrode material that can be used for the anode and the cathode of the energy storage capacitor. In order to achieve this, two electrode plates having at least one mixed electrode formed by mixing activated carbon and carbon nanofibers having at least one of a positive electrode and a negative electrode, an electrolyte formed between the two electrode plates to flow a current; It is located in the middle of the electrolyte comprises a separator for separating the electrolyte.

Super Capacitor, Mixed Electrode Material, Activated Carbon, Carbon Nanofiber

Description

Energy storage capacitor and method for fabricating the same

1 is a view showing the ultra-high capacity expression principle of a general super capacitor

Figure 2a, 2b is a view showing the configuration of an energy storage capacitor according to the present invention

Figure 3 is a schematic diagram of the configuration of the energy storage capacitor electrode material according to the present invention

4 is a flowchart illustrating a process of manufacturing an electrode material according to an energy storage capacitor according to the present invention.

* Explanation of symbols for main parts of the drawings

10 porous porous nanocarbon electrode 20 electrolyte anion

30: electrolyte cation 100: electrode plate

110: activated carbon 120: carbon nanofiber

200: electrolyte 300: separator

400: metal film 500: energy storage capacitor

600: Load 700: Power

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to energy storage capacitors, and more particularly, to the construction and manufacturing method of energy storage capacitors using electrode materials suitable for realizing high output and energy density.

As an energy storage device for systems that require independent power supply such as various portable electronic devices and electric vehicles, or systems that regulate / supply instantaneous overloads, batteries are often considered first, but are not yet available for practical use. No suitable storage system has been developed.

In terms of energy input and output (ie, power) in the process of storing and utilizing electrical energy, capacitors perform better than batteries.

This is because the energy storage mechanism of the capacitor is due to the kinetic mechanism of very fast and reversible ions, unlike batteries which rely on thermodynamic mechanisms with redox processes, resulting in fast charging and charging and discharging efficiency. This is because it is higher than this battery and the charge / discharge repeated service life becomes very long.

The dual energy storage capacitor is a capacitor that functions as a conventional capacitor and has a mechanism for storing energy. It is an energy storage device that can serve as a bridge between a battery and a capacitor.

In terms of energy density and power density, an energy storage capacitor having intermediate characteristics between an electrolytic capacitor and a secondary battery has a shorter charging time, a longer life, and a higher power than a secondary battery, and is 10 times more energy than a conventional electrolytic capacitor. Is a high system. That is, it means a system combining only the advantages of the power characteristics of the electrolytic capacitor and the high energy storage characteristics of the secondary battery.

The reason why the energy storage capacitor can act as a middle part between the battery and the existing capacitor, that is, the reason why it can have a high energy density and power density at the same time can be understood as follows.

An energy storage capacitor is a type of electrical energy storage device that converts and stores a chemical reaction into electrical energy by using an electrostatic orientation (electrochemical double-layer) of ions at an electrode / electrolyte interface.

That is, the capacitance (C) value in the existing capacitor is proportional to the contact area and inversely proportional to the distance between the positive and negative charges, that is, the thickness of the dielectric layer.

In the energy storage capacitor, the area of the energy storage capacitor is increased by using a nanoscale porous carbon electrode material. In addition, the energy storage capacitor is shown in FIG. As can be seen, the thickness of the dielectric layer is reduced to an ionic layer of 10 占 so that the value of capacitance can be increased to an ultra high capacity.

Such an energy storage capacitor has been described in other words as a super capacitor.

The supercapacitors are classified into two types according to their operation principle, one of which is an electrochemical double-layer capacitor which stores electric charges in an electric double layer of an electrode / electrolyte interface, and the other is a virtual capacitor ( It is called a pseudo capacitor and is a redox capacitor that carries a change in the valence of transition metal ions on the surface of the transition metal oxide and stores charge or electrons.

Although the electric double layer capacitor has a theoretically large specific surface area using activated carbon, the area that can be calculated and used as the actual capacitance value is only 20-30% of the total. This is because the size and the degree of adsorption of ions in the electrolyte to adhere to the activated carbon.

That is, the porous activated carbon may be classified into three types such as pore size of micro (20Å <), meso (20Å <pore size <100Å), and macropore (> 100Å). . Of these, when the pore size is micropores, the ions in the electrolyte may not be a suitable size to enter the pores. Therefore, when the pore size of the activated carbon has a large number of micropores, it results in a dramatically increased specific surface area, which is an advantage of using activated carbon.

Therefore, maintaining a pore structure suitable for the size of a predetermined electrolyte ion is a way to increase the power density of the energy storage capacitor. However, this leads to costly and time-consuming loss of several heat treatments and additional processes. In addition, the internal resistance measured after fabricating the actual device (typically measured by impedance at 1kHz) ranges from several Ω to several tens of Ω. This, in turn, lowers the impedance matching effect when serving as an auxiliary function of the battery, resulting in a decrease in overall system usage efficiency.

In addition, the use of a single type of transition metal oxide in the redox capacitor is greatly reduced in cost and efficiency. For example, RuO ₂ has proved to be the most energy-saving property at present, but the disadvantage is that it is unsuitable for mass production due to its high price, and the charge-discharge curve is nonlinear in terms of efficiency.

Therefore, the present invention has been made to solve the above problems, overcoming the disadvantages in the current energy storage capacitor by newly designing the configuration of the electrode material that can be used for the anode and cathode of the energy storage capacitor and The purpose is to provide an energy storage capacitor that can improve its function.

Another object of the present invention is to provide an energy storage capacitor which effectively works in the insertion, adsorption and desorption of electrolyte ions by using a mixture of activated carbon and carbon nanofibers.

It is still another object of the present invention to provide an energy storage capacitor that mixes activated carbon and carbon nanofibers to facilitate electron movement, thereby reducing internal resistance and contributing to improved efficiency when used as an auxiliary device of a battery. .

Features of the energy storage capacitor according to the present invention for achieving the above object are two electrode plates having at least one mixed electrode formed by mixing the active carbon and carbon nanofibers having any one of a positive electrode and a negative electrode; And an electrolyte that is formed between the two electrode plates to flow a current, and a separator that is positioned in the middle of the electrolyte to separate the electrolyte.

Preferably, the electrode plate composed of the mixed electrode is characterized in that it further comprises a metal film on top.

Preferably, the metal film has a thickness of several tens of micrometers (micrometer).

Preferably, the metal film is made of Al, Cu or Ni thin film (foil).

이상 3000

이하를 갖는 활성탄소와, 직경이 수십부터 수백 nm이고 길이가 수에서 수십 마이크로미터를 갖는 카본나노파이버와, 도전재로 카본블랙 혹은 나노금속으로 구성되는 것을 특징으로 한다.Preferably the hybrid electrode has a specific surface area of 1500

More than 3000

It is characterized by consisting of activated carbon having the following, carbon nanofibers having a diameter of several tens to hundreds of nm and a few tens of micrometers in length, and carbon black or nano metal as a conductive material.

Preferably the mixed electrode is characterized in that consisting of a thickness of less than 200㎛.

Preferably, the mixed electrode is configured such that the proportion of the carbon nanofibers occupies 1% or more and 99 wt% or less, and the mixing ratio of the carbon black or nanometal occupies 15 wt% or less. It is done.

Preferably the electrolyte is characterized by consisting of any one of an aqueous electrolyte and an organic electrolyte.

Preferably, the separator is characterized in that it is composed of any one of polypropylene and polyethylene series.

Features of the manufacturing method of the energy storage capacitor according to the present invention for achieving the above object is to prepare an electrode material in the form of a slurry (slurry) by mixing activated carbon and carbon nanofibers, the top and Coating an electrode material prepared in the form of the slurry on at least one of the lower parts, applying a predetermined pressure to the coated current collector with a roller or a phrase to form an electrode material having a predetermined thickness, and the coated electrode Performing vacuum drying and heat treatment of the ash, and compressing the ash in a sandwich form with a separator between the formed electrode materials, and injecting an electrolyte.

Preferably the coating step is characterized in that the coating further comprises a metal film after the electrode material coating.

Preferably, the metal film is coated with a thickness of several tens of micrometers (micrometer).

Preferably, the metal film is formed of an Al, Cu or Ni thin film.

Preferably, the electrode material is characterized in that the mixing ratio is formed so that the carbon nanofibers are 1wt% or more and 99wt% or less of the total ratio.

Preferably, the electrolyte is characterized by consisting of at least one of an aqueous and non-aqueous electrolyte.

Preferably, when the electrolyte is an aqueous electrolyte, the solvent of the aqueous electrolyte is characterized in that at least one of distilled water (Distilled water), 2-butoxy ethanol and iso-propyl alcohol.

Preferably, when the electrolyte is an organic electrolyte, the solvent of the organic electrolyte is NMP (N-methyl pyrrolidinone) or DMF (N-dimethyl formamide).

Preferably, the step of preparing the electrode material is characterized in that to produce a slurry (slurry) by mixing a binder and a plasticizer in a predetermined ratio.

Preferably, when the electrolyte is an aqueous electrolyte, the binder is characterized by using PVA (Poly Vinyl Alcohol) or CMC (Carboxy Methyl Cellulose).

Preferably, when the electrolyte is an organic electrolyte, the binder is characterized by using at least one of polyvinylidene fluoride (PVDF) and polyacrylic vinyl copolymer (PACo).

Preferably the binder is characterized in that the mixing ratio is less than 10 wt%.

Preferably, the predetermined thickness of the electrode material is characterized in that it has within 200㎛.

Preferably the coating of the current collector is characterized in that the coating using a spray (spray) or doctor blade (doctor blade) method.

Preferably the heat treatment is characterized in that performed between 100 to 500 degrees.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the accompanying drawings.

An embodiment of an energy storage capacitor and a method of manufacturing the same according to the present invention will be described with reference to the accompanying drawings.

Figure 2a is a view showing the configuration of the energy storage capacitor according to the present invention, Figure 2b is a view showing a circuit diagram of the energy storage capacitor according to the present invention.

As shown in FIG. 2A, the structure of the energy storage capacitor includes two electrode plates 100 having at least one mixed electrode formed by mixing activated carbon and carbon nanofibers having any one of a positive electrode and a negative electrode, and the two It is composed of an electrolyte 200 is formed between the electrode plate 100 to flow a current, and the separator 300 is located in the middle of the electrolyte 200 to separate the electrolyte.

In this case, the electrode plate 100 composed of the mixed electrode further includes a metal film 400 thereon.

In addition, as shown in FIG. 2B, the energy storage capacitor 500 is implemented to be connected to the power source 700 and the load 600 in parallel.

A schematic diagram of the mixed electrode 100 is shown in detail in FIG. 3.

이상 3000

이하를 갖는 활성탄소(110)와, 직경이 수십부터 수백 nm이고, 길이가 수에서 수 마이크로미터(micrometer) 이하를 갖는 카본나노파이버(120)가 혼합되어 구성된다 As shown in FIG. 3, the mixed electrode has a specific surface area of 1500.

More than 3000

It consists of an activated carbon 110 having a diameter and carbon nanofibers 120 having a diameter of several tens to hundreds of nm and a length of several micrometers or less.

At this time, the carbon nanofiber 120 is configured to have a mixing content of 1 wt% to 99 wt% in total content. In addition, it is preferable to further mix carbon black or nanometal to the mixed electrode as a conductive material, and the mixing content is configured to have 15wt% or less.

The electrolyte 200 may be either an aqueous electrolyte or an organic electrolyte, and the separator may be polypropylene or polyethylene-based.

When described in detail with reference to the accompanying drawings, a method for manufacturing an energy storage capacitor according to the present invention configured as described above.

4 is a flowchart illustrating a process of manufacturing an electrode material according to the energy storage capacitor according to the present invention.

부터 3000

을 갖는 활성탄소(110)와 직경이 수십부터 수백 nm이고 길이가 수에서 수십 마이크로미터를 갖는 카본나노파이버(120)를 혼합하여 혼합형 전극을 생성한다 (S10). Referring to Figure 4, first, the mixing ratio of the carbon nanofibers 120 is 1wt% or more and 99wt% or less of the total ratio so that the specific surface area is 1500

From 3000

The carbon nanofibers 120 having an activated carbon 110 having a diameter of several tens to several hundred nm and a tens of micrometers in length are mixed to generate a mixed electrode (S10).

In this case, preferably, carbon black or nanometal is added to the mixed electrode so that the total ratio is 15 wt% or less, and mixed.

An embodiment according to the mixing conditions of the activated carbon and carbon nanofibers is as follows.

Example 1

When using an aqueous electrolyte,

A suitable binder and a plasticizer are mixed in a suitable proportion to a carbon nanofiber 120 having a mixed content of porous activated carbon 110 and 1 wt% to 99 wt% of the total ratio to prepare a slurry.

In this case, as the slurry conditions, the solvent of the aqueous electrolyte is mixed with distilled water and 2-butoxy ethanol or iso-propyl alcohol. Then, PVA (Poly Vinyl Alcohol) or CMC (Carboxy Methyl Cellulose) is used as the binder, and the content is mixed below 10 wt%. In addition, the plasticizer may not be used in some cases, and when used, polyethylene glycol (PEG) is used.

In the case of the PVA used as the binder, dissolution is performed while stirring the water near the breaking point of the water when mixing with distilled water.

Example 2

When using an organic electrolyte,

The porous activated carbon 110 and the carbon nanofiber 120 having a mixed content of 1 wt% to 99 wt% of the total ratio are mixed in an appropriate ratio of a binder and a plasticizer to prepare a slurry.

At this time, the solvent of the organic electrolyte that can be used as the production conditions in the form of the slurry is NMP (N-methyl pyrrolidinone) or DMF (N-dimethyl formamide) is used. In addition, PVdF (poly vinylidene fluoride) or PACo (polyacrylic vinyl copolymer) is used as the binder, and the content of the binder is mixed at 10 wt% or less.

Subsequently, the mixed electrode 100 manufactured in the slurry form is coated on the current collector (S20).

At this time, the coating on the current collector using a doctor blade (doctor blade) method which is a kind of spray (spray) or tape casting (Tape casting). And the solvent of the prepared slurry can be applied to both aqueous and non-aqueous.

Then, the coated current collector is applied with a predetermined pressure with a roller or a place to form an electrode material having a thickness of 200 μm or less (S30).

Thereafter, the coated electrode material is subjected to vacuum drying and heat treatment (S40).

That is, moisture and organic solvents are removed in a vacuum drying furnace and heat treatment is performed within 200 degrees in a box furnace. By doing so, it is possible to improve the surface quality of the coating electrode by evaporating all the remaining organic solvent or water and maximizing the role of the binder.

In this case, the process may be simplified by applying mechanical pressure to match the thickness of the coating layer or simultaneously applying pressure and temperature by a hot press method. At this time, the temperature is heat treated between 100 degrees and 500 degrees and the applied pressure is up to 10 kg / cm 2 to achieve densification of the coating layer.

Then, the metal film 400 is formed of an Al, Cu or Ni thin film having a thickness of several tens of micrometers (micrometer) on the outer surface of the mixed electrode 100 coated (S50).

Finally, after the separation membrane 300 is sandwiched and sandwiched in a sandwich form, an electrolyte 200 is injected to manufacture an energy storage capacitor (S60). At this time, the solvent of the injected electrolyte can be applied to both aqueous and non-aqueous.

The separator 300 is preferably composed of any one of polypropylene and polyethylene series.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

An energy storage capacitor and a method of manufacturing the same according to the present invention as described above have the following effects.

First, the present invention increases energy use efficiency and maximizes performance and function of the battery when used in combination with a secondary battery through the composition of an electrode material that can make the most of the advantages of the conventional energy storage capacitor through the present invention. You can expect an extension.

Second, the application of the present invention can maximize the use of energy storage capacitors through the modification of the electrode material design, which can be utilized in various elements of various power systems using electric energy, thereby having enormous demand potential. Can be. At its closest, the focus is on its use as an energy source to be replaced with secondary batteries.

Third, by applying the present invention, it is expected that the present invention can be applied as an inexpensive and excellent battery replacement capacitor to all portable small electronic devices.

Claims (24)

Two electrode plates having at least one of a positive electrode and a negative electrode and having at least one mixed electrode formed by mixing activated carbon and carbon nanofibers; An electrolyte formed between the two electrode plates to flow a current; Energy storage capacitor, characterized in that it comprises a separator located in the middle of the electrolyte to separate the electrolyte. The method of claim 1, The electrode plate composed of the mixed electrode further comprises a metal film on top of the energy storage capacitor. The method of claim 2, The metal film is energy storage capacitor, characterized in that having a thickness of several tens (micrometer). The method of claim 2, The metal film is an energy storage capacitor, characterized in that consisting of Al, Cu or Ni thin film (foil). The method of claim 1, wherein the mixed electrode Specific surface area 1500

More than 3000

Activated carbon having the following Carbon nanofibers having a diameter of tens to hundreds of nm and a length of several tens of micrometers, Energy storage capacitor, characterized in that composed of either carbon black or nano metal. The method of claim 1, The energy storage capacitor, characterized in that the mixed electrode is composed of a thickness of less than 200㎛. The method of claim 1, The mixed electrode is configured such that the mixing ratio of the carbon nanofibers occupies 1% or more and 99 wt% or less, and the mixing ratio of the carbon black or nanometal occupies 15 wt% or less. Energy storage capacitor, characterized in that. The method of claim 1, The electrolyte is characterized in that it is composed of any one of an aqueous electrolyte and an organic electrolyte, When the electrolyte is an aqueous electrolyte, the solvent is at least one of distilled water, 2-butoxy ethanol and iso-propyl alcohol, When the electrolyte is used as the organic electrolyte, the solvent is NMP (N-methyl pyrrolidinone) or DMF (N-dimethyl formamide) characterized in that the energy storage capacitor. The method of claim 1, The separator is an energy storage capacitor, characterized in that composed of any one of polypropylene and polyethylene series. Preparing an electrode material in the form of a slurry by mixing activated carbon and carbon nanofibers; Coating an electrode material manufactured in the form of the slurry on at least one of upper and lower portions of a current collector; Applying a predetermined pressure to the coated current collector with a roller or a place to form an electrode material having a predetermined thickness; Performing vacuum drying and heat treatment on the coated electrode material; An energy storage capacitor manufacturing method comprising the step of placing a separator between the formed electrode material and crimping in a sandwich form, injecting an electrolyte. The method of claim 10, The coating step is a method of manufacturing an energy storage capacitor, characterized in that the coating further comprises a metal film after the electrode material coating. The method of claim 11, The metal film is energy storage capacitor manufacturing method characterized in that the coating to a thickness of several tens (micrometer). The method of claim 11, The metal film is Al, Cu or Ni thin film (foil) characterized in that the energy storage capacitor manufacturing method characterized in that. The method of claim 10, The electrode material is an energy storage capacitor manufacturing method characterized in that the mixing ratio is formed so that the carbon nanofibers are 1wt% or more and 99wt% or less of the total ratio. The method of claim 10, The electrolyte is a method of manufacturing an energy storage capacitor, characterized in that at least one of an aqueous and non-aqueous electrolyte. The method according to claim 15, wherein when the electrolyte is an aqueous electrolyte, The solvent of the aqueous electrolyte is an energy storage capacitor manufacturing method characterized in that at least one of distilled water (Distilled water), 2-butoxy ethanol and iso-propyl alcohol. The method of claim 15, wherein when the electrolyte is an organic electrolyte, The solvent of the organic electrolyte is NMP (N-methyl pyrrolidinone) or DMF (N-dimethyl formamide) method for producing an energy storage capacitor, characterized in that. The method of claim 10, The manufacturing of the electrode material is a method of manufacturing an energy storage capacitor, characterized in that to produce a slurry (slurry) by mixing a binder and a plasticizer in a predetermined ratio. 19. The method of claim 18, wherein when the electrolyte is an aqueous electrolyte, The binder is PVA (Poly Vinyl Alcohol) or CMC (Carboxy Methyl Cellulose) energy storage capacitor manufacturing method characterized in that using. The method of claim 18, wherein when the electrolyte is an organic electrolyte, The binder is an energy storage capacitor manufacturing method characterized in that using at least one of PVdF (poly vinylidene fluoride) and PACo (polyacrylic vinyl copolymer). The method of claim 18, The binder is an energy storage capacitor manufacturing method, characterized in that the mixing ratio is less than 10 wt%. The method of claim 10, The predetermined thickness of the electrode material has a method of producing an energy storage capacitor, characterized in that less than 200㎛. The method of claim 10, The coating of the current collector is an energy storage capacitor manufacturing method characterized in that the coating using a spray (spray) or doctor blade (doctor blade) method. The method of claim 10, The heat treatment is an energy storage capacitor manufacturing method, characterized in that performed between 100 to 500 degrees.

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