KR20110040027A - Hybrid supercapacitor and manufacturing method of the same - Google Patents

Abstract

PURPOSE: A hybrid super capacitor and a manufacturing method thereof are provided to improve energy density per unit volume by doping lithium on activated carbon. CONSTITUTION: An anode includes materials which cations are inserted into or separated from according to charging or discharging. A cathode includes activated carbon which is doped with lithium and has low potential. A separation film prevents the short of the cathode and the anode. An electrolyte with dissolved lithium salt is between the anode and the cathode. A specific surface of the activated carbon is 300 to 2000 m^2/g.

Description

Hybrid supercapacitor and manufacturing method of the same

The present invention relates to a hybrid supercapacitor and a method of manufacturing the same, and more particularly, to a hybrid supercapacitor having a high energy density per unit volume and composed of activated carbon having a lower potential due to lithium doping, and a method for manufacturing the hybrid supercapacitor.

Supercapacitors are also commonly referred to as Electric Double Layer Capacitors (EDLC), Super-capacitors or Ultra-capacitors, which are the interface between electrodes and conductors and the electrolyte solution impregnated therewith. By using a pair of charge layers (electric double layers) each having a different sign, the deterioration due to repetition of the charge / discharge operation is very small and requires no maintenance. As a result, supercapacitors are mainly used to back up ICs (integrated circuits) of various electrical and electronic devices. Recently, they are widely used in toys, solar energy storage, and hybrid electric vehicle (HEV) power supplies. It is.

Such a supercapacitor generally includes two electrodes of a positive electrode and a negative electrode impregnated with an electrolyte, a separator made of a porous material interposed between the two electrodes to allow only ion conduction, and to prevent insulation and short circuit, and an electrolyte solution. It has a unit cell consisting of a gasket for preventing leakage and preventing insulation and short circuit, and a metal cap as a conductor for packaging them. One or more unit cells (usually, 2 to 6 in the case of a coin type) configured as described above are stacked in series and completed by combining two terminals of a positive electrode and a negative electrode.

As the active material of the positive electrode and the negative electrode of the conventional capacitor, a carbon material such as activated carbon is most widely used. Since the carbon material has characteristics of fast charge and discharge and a long life, a hybrid capacitor in which an active carbon of a positive electrode is replaced with a lithium transition metal oxide is used.

Hybrid supercapacitors using activated carbon powder as a cathode and lithium oxide as a cathode are disclosed in Korean Patent Laid-Open Publication No. 10-2002-0009751 and Korean Patent Publication No. 10-2001-7013373. In Korean Patent Laid-Open Publication Nos. 10-2002-0009751 and 10-2001-7013373, activated carbon powder is used as a negative electrode material and lithium oxide is used as a positive electrode material, but it is difficult to increase the energy density of a capacitor due to the limitation of the operating voltage. There is this.

In the present invention, by supplementing the low potential difference between activated carbon and lithium metal, the cathode potential is reduced by doping lithium on the activated carbon, and the insertion and desorption of lithium on the surface and the bulk of the activated carbon results in an increase in operating voltage and capacity. To present.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a hybrid supercapacitor having a high energy density per unit volume and a method of manufacturing the same by lowering a cathode potential by doping lithium on activated carbon. .

The present invention provides a positive electrode including a material capable of inserting or desorbing cations according to a charging or discharging operation, a negative electrode including activated carbon doped with lithium and having a lower potential, and a separator for preventing a short circuit between the positive electrode and the negative electrode. And it provides a hybrid supercapacitor comprising an electrolyte solution in which lithium salt is dissolved between the positive electrode and the negative electrode.

In the hybrid supercapacitor, the surface and the inside of the activated carbon are doped with lithium along the steps of pores formed in the activated carbon, and lithium is inserted or removed from both the surface and the inside of the activated carbon according to a charging or discharging operation.

The anode includes a lithium transition metal oxide, the lithium transition metal oxide is a complex metal oxide of a layer structure, a spinel structure or an olivine structure containing lithium and transition metal, the transition metal is titanium (Ti), vanadium It is preferably at least one metal selected from the group consisting of (V), manganese (Mn), iron (Fe), cobalt (Co) and nickel.

The specific surface area of the lithium transition metal oxide is preferably in the range of 0.1 to 100 m 2 / g.

The lithium salt is preferably composed of at least one salt selected from LiPF ₆ , LiBF ₄ , LiClO ₄ , Li (CF ₃ SO ₂ ) ₂ , LiCF ₃ SO ₃ , LiSbF _6, and LiAsF ₆ .

It is preferable that the specific surface area of the said activated carbon is 300-2200 m <2> / g.

The hybrid supercapacitor has an operating voltage equal to or greater than 2.5V.

In addition, the present invention, the working electrode including the activated carbon, and the counter electrode including a lithium foil (Li foil) are arranged to be spaced apart from each other, and the working electrode and the counter electrode are impregnated with an electrolyte solution in which lithium salt is dissolved. Injecting, applying a voltage of −0.1 V to 0.6 V to the working electrode, doping lithium from the counter electrode and the lithium salt to be doped and electrodeposited on and in the surface of the activated carbon and lithium doping It provides a method of manufacturing a hybrid supercapacitor comprising the step of manufacturing a hybrid supercapacitor using the activated carbon electrode comprising the activated carbon.

The manufacturing of the hybrid supercapacitor may include a positive electrode including a lithium transition metal oxide, a negative electrode including activated carbon doped with lithium and a lower potential, and a short circuit between the positive electrode and the negative electrode between the positive electrode and the negative electrode. And disposing a separator for injecting an electrolyte solution in which lithium salt is dissolved between the positive electrode and the negative electrode, wherein the positive electrode is mixed with a lithium transition metal oxide, a conductive material, a binder, and a dispersion medium. It comprises a step of preparing a mixture comprising the coating on the metal foil, the mixture, the mixture is 100 parts by weight of lithium transition metal oxide, 2 to 15 parts by weight of conductive material based on 100 parts by weight of lithium transition metal oxide 2-10 parts by weight of the binder, and the dispersion medium was added in 200 parts by weight of 100 parts by weight of the lithium transition metal oxide. It is preferably added in portions than the large and small content of less than 300 parts by weight.

The negative electrode includes the steps of preparing an activated carbon mixture by mixing activated carbon, a conductive material, a binder and a dispersion medium, and coating the activated carbon mixture on a metal foil, wherein the activated carbon mixture is 100 parts by weight of activated carbon and 100 parts by weight of activated carbon. It is preferably added in an amount of 2 to 20 parts by weight of the conductive material and 2 to 10 parts by weight of the binder, and the dispersion medium is added in an amount of more than 200 parts by weight and less than 300 parts by weight with respect to 100 parts by weight of activated carbon.

In the method of manufacturing the hybrid supercapacitor, the surface and the inside of the activated carbon are doped with lithium along the steps of pores formed in the activated carbon, so that the insertion or desorption of lithium is performed on both the surface and the inside of the activated carbon according to a charging or discharging operation. do.

According to the present invention, the activated carbon constituting the cathode of the hybrid supercapacitor is doped with lithium by using lithium electrodeposition, thereby lowering the potential of the anode, and insertion and desorption by lithium not only on the surface of the activated carbon but also inside the activated carbon Therefore, the hybrid supercapacitor of the present invention has a high energy density per unit volume.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and the scope of the present invention is limited to the embodiments described below. It doesn't happen.

The present invention provides a positive electrode including a material capable of inserting or desorption of cations according to a charging or discharging operation, a negative electrode including activated carbon doped with lithium and having a lower potential, and a separator for preventing a short circuit between the positive electrode and the negative electrode ( Separator) and provides a hybrid supercapacitor comprising an electrolyte solution in which lithium salt is dissolved between the positive electrode and the negative electrode.

The positive electrode of the hybrid supercapacitor of the present invention is a material capable of inserting or detaching cations into an electrolyte according to a charging or discharging operation, and includes a lithium transition metal oxide. The lithium transition metal oxide is a complex metal oxide having a layered structure, a spinel structure, or an olivine structure including lithium and a transition metal, and the transition metal is titanium (Ti), vanadium (V), manganese (Mn), iron ( Fe), cobalt (Co) and nickel may be at least one metal selected from the group consisting of. Examples of such lithium transition metal oxides include LiMn ₂ O ₄ , LiCoO ₂ , LiNi _1/3 Co _1/3 Mn _1/3 O ₂ , and the like. The specific surface area of the lithium transition metal oxide is preferably in the range of 0.1 to 100 m 2 / g.

The negative electrode of the present invention uses an electrode containing activated carbon doped with lithium on its surface and inside.

Hereinafter, a method of manufacturing the cathode of the hybrid supercapacitor of the present invention will be described in detail with reference to FIG. 1.

Referring to FIG. 1, an activated carbon mixture is prepared by mixing activated carbon powder, a binder, a conductive material, and a dispersion medium.

In the compounding quantity of the said activated carbon mixture, it is preferable to add 2-20 weight part of conductive materials, and 2-10 weight part of binders with respect to 100 weight part of activated carbon powders. The content of the dispersion medium is not particularly limited but is added to less than 300 parts by weight and greater than 200 parts by weight based on 100 parts by weight of the activated carbon powder.

The activated carbon powder is not particularly limited and may be used activated carbon used in general electrode production. For example, coconut shell-based activated carbon, phenol resin-based activated carbon, and the like may be used, which includes partially crystalline activated carbon. It is preferable that the specific surface area of the activated carbon powder used is 300-2200 m <2> / g. The particle size of the activated carbon powder is preferably in the range of 0.9 to 20 μm in order to facilitate electrode molding and dispersion.

The conductive material is not particularly limited as long as it is an electronic conductive material that does not cause chemical change, and examples thereof include metal powder or metal such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fiber, copper, nickel, aluminum, silver, and the like. Fiber and the like.

In addition, the binder is polytetrafluoroethylene (PTFE), polyvinylidenefloride (PVDF), carboxymethylcellulose (CMC), polyvinyl alcohol (poly vinyl alcohol; PVA), polyvinyl butyral One or two or more selected from polyvinyl butyral (PVB), poly-N-vinylpyrrolidone (PVP), styrene butadiene rubber (SBR), and the like may be used.

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

The activated carbon mixture is coated on both sides of a metal foil such as an aluminum etching foil to prepare a working electrode 20. The aluminum etching foil means that the aluminum foil is etched in an uneven shape. The working electrode 20 coated with both surfaces of the activated carbon mixture on the metal foil and the counter electrode 30 made of lithium foil are disposed in the reaction tank 10 so as to be spaced apart from each other, and an electrolyte in which lithium salt is dissolved ( 40 is injected between the working electrode 20 and the counter electrode 30 so that the working electrode 20 and the counter electrode 30 are impregnated in the electrolyte 40.

The lithium salt is not particularly limited as a lithium salt commonly used in capacitors, for example, LiPF ₆ , LiBF ₄ , LiClO ₄ , Li (CF ₃ SO ₂ ) ₂ , LiCF ₃ SO ₃ , LiSbF ₆ or LiAsF ₆ Etc. can be used.

Although the solvent which comprises the said electrolyte solution is not specifically limited, A cyclic carbonate solvent, a linear carbonate solvent, ester solvent, an ether solvent, a nitrile solvent, an amide solvent, etc. can be used. Ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, etc. may be used as the cyclic carbonate solvent, and dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, etc. may be used as the chain carbonate solvent. As the ester solvent, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, and the like may be used. The ether solvent may be 1,2-dimethoxyethane or 1,2-diene. Methoxyethane, tetrahydrofuran, 1,2-dioxane, 2-methyltetrahydrofuran, etc. may be used, and acetonitrile may be used as the nitrile solvent, and dimethylformamide may be used as the amide solvent. Can be used.

In the reactor 10 arranged as described above, a lithium foil is used as a counter electrode 30, and a power supply of -0.1 V to 0.6 V is supplied to the working electrode 20 including activated carbon. Apply voltage. It is preferable to apply -0.1 to 0.6V to the working electrode 20. When the applied voltage is less than -0.1V, although lithium doping is performed, uniform doping may be difficult and the applied voltage exceeds 0.6V. In this case, since the amount of lithium doped is small, there may be a limit to improving the energy density per unit volume of the hybrid supercapacitor, it is preferable to apply a voltage within the above range. The time for applying the voltage is preferably about 5 minutes to 120 minutes. When the time for applying the voltage is less than 5 minutes, the amount of lithium doped is small, which limits the energy density per unit volume of the hybrid supercapacitor. For example, when the time for applying the voltage exceeds 120 minutes, it is difficult to expect an improvement in energy density per unit volume.

When a voltage is applied to the working electrode 20, lithium is doped (electrodeposited) on the surface of the activated carbon constituting the working electrode 20. Lithium from the lithium foil forming the counter electrode 30 reaches the surface of the activated carbon through the electrolyte 40 and is doped onto the surface of the activated carbon, and lithium from the lithium salt contained in the electrolyte 40 It reaches the surface of activated carbon and is doped to the surface of activated carbon. The lithium foil forming the counter electrode 30 serves as a source of lithium in doping activated carbon with lithium, and the lithium salt contained in the electrolyte also serves as a source of lithium in doping activated carbon with lithium. . Lithium doped in activated carbon by the lithium electrodeposition method decreases the cathode potential in a hybrid capacitor using an activated carbon electrode as a cathode, thereby intercalation and deintercalation by lithium doped on the surface of the active plate during charging and discharging. ) Will happen quickly. The insertion and desorption of lithium doped on the surface of activated carbon results in a high energy density per unit volume of the hybrid supercapacitor of the present invention. In addition, the activated carbon constituting the working electrode 20 has a number of pores (pore), by the lithium electrodeposition method described above lithium is not doped only on the surface of the activated carbon, but along the pores connected to the inside or bulk (vulk) Doping is also performed deep inside the activated carbon. As such, lithium is doped not only on the surface of activated carbon, but also on the bulk (inside), so that insertion and desorption processes occur in the bulk of activated carbon during charging and discharging.

On the other hand, activated carbon and lithium have a potential difference of about 0.3V as shown in FIG. In FIG. 2, (a) is a graph showing time vs. voltage characteristics for activated carbon, and (b) is a graph showing time vs. voltage characteristics for lithium. As can be seen from FIG. 2, when lithium is doped on the surface of the activated carbon constituting the negative electrode, the negative electrode potential decreases, and the capacity of the hybrid supercapacitor is increased by insertion and desorption by lithium doped on the surface of the activated carbon. It is effective. For example, if the capacitor using the lithium-doped activated carbon as the negative electrode has an operating voltage of 2.3V, the capacitor using the lithium-doped activated carbon as the negative electrode may have an operating voltage of about 2.6V.

A hybrid supercapacitor that realizes high energy density per unit volume may be manufactured using a negative electrode including lithium-doped activated carbon.

The hybrid supercapacitor of the present invention includes a positive electrode including a lithium transition metal oxide, a negative electrode including activated carbon doped with lithium and a potential lowered, and a separator for preventing a short circuit between the positive electrode and the negative electrode between the positive electrode and the negative electrode ( A separator may be disposed, and an electrolyte solution containing lithium salt dissolved between the positive electrode and the negative electrode may be injected.

The positive electrode may be prepared by mixing a lithium transition metal oxide, a conductive material, a binder, and a dispersion medium to prepare a mixture including the lithium transition metal oxide, and coating the mixture on a metal foil. The mixture is added to 100 parts by weight of the lithium transition metal oxide, 2 to 15 parts by weight of the conductive material and 2 to 10 parts by weight of the binder with respect to 100 parts by weight of the lithium transition metal oxide, and the dispersion medium is 100 parts by weight of the lithium transition metal oxide. It is preferable to add more than 200 parts by weight to less than 300 parts by weight. The specific surface area of the lithium transition metal oxide is preferably in the range of 0.1 to 100 m 2 / g.

The separator may be 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 the like. If the separator is generally used in the field is not particularly limited.

On the other hand, the electrolyte of the electrolyte solution filled in the hybrid supercapacitor of the present invention uses a lithium salt dissolved as a non-aqueous electrolyte. The lithium salt is not particularly limited as a lithium salt commonly used in capacitors, for example, LiPF ₆ , LiBF ₄ , LiClO ₄ , Li (CF ₃ SO ₂ ) ₂ , LiCF ₃ SO ₃ , LiSbF ₆ or LiAsF ₆ Etc.

Although the solvent of the said electrolyte solution is not specifically limited, A cyclic carbonate solvent, a linear carbonate solvent, an ester solvent, an ether solvent, a nitrile solvent, and an amide solvent can be used. For example, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, or the like may be used as the cyclic carbonate solvent, and dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, or the like may be used as the chain carbonate solvent. The ester solvent may be methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, etc., and the ether solvent may be 1,2-dimethoxyethane, 1 , 2-diethoxyethane, tetrahydrofuran, 1,2-dioxane, 2-methyltetrahydrofuran, etc. may be used, and acetonitrile may be used as the nitrile solvent, and the amide solvent may be used. Dimethylformamide and the like can be used.

The hybrid supercapacitor of the present invention manufactured as described above has an operating voltage of 2.6 V or more per unit cell, and a capacity of 40 F / cc is possible.

Hereinafter, specific examples and comparative examples of the present invention will be described. However, the following examples are merely provided to explain the present invention in more detail, and do not limit the technical scope of the present invention.

<Examples>

100 parts by weight of MSP20 activated carbon having a particle size of 0.9 to 20 μm (manufactured by Kansai Thermochemical Co., Ltd.) and 15 parts by weight of conductive material Super-P Black (manufactured by Kuraray Chemical Co., Japan) were dry mixed. Separately, 3 parts by weight of carboxymethyl cellulose (CMC) was added to the distilled water and mixed. The mixture was added to a planetary mixer (manufacturer: TK, model name: Hivis disper), stirred for 1 hour, dispersed, and mixed with stirring for 1 hour by adding 9.8 parts by weight of styrene-butadiene rubber (SBR). Activated carbon mixture was obtained.

Next, the activated carbon mixture was coated on both sides of a 20 μm aluminum etching foil to produce an activated carbon electrode having a thickness of 200 μm including an aluminum etching foil.

The prepared activated carbon electrode was used as a working electrode, and a lithium foil (Li foil) was used as a counter electrode to impregnate the electrolyte containing lithium salt, and then applied to the working electrode at a voltage of 0 V for 60 minutes to supply a lithium foil and Lithium of the lithium salt was allowed to be doped into the working electrode through the electrolyte. The lithium-doped activated carbon electrode was used as the negative electrode.

100 parts by weight of LiMn ₂ O ₄ (phoenix ICP) having a specific surface area of about 0.43 m 2 / g and 10 parts by weight of Super-p black (manufactured by Kuraray Chemical, Japan) as a conductive material were dry mixed. Separately, 10 parts by weight of polyvinylidene fluoride (PVdF) was added to N-methyl-2-pyrrolidone (NMP), which is methyl pyrrolidone, and mixed. Then, the two mixtures were added to a planetary mixer (manufacturer: TK, model name: Hivis disper), dispersed by stirring for 1 hour, dispersed, and then mixed with stirring for 1 hour by adding NMP 60 parts to lithium transition metal. A mixture comprising an oxide was obtained.

Next, an electrode was prepared by double-coating a mixture including the lithium transition metal oxide on a 20 μm aluminum etching foil. The thickness of the electrode thus prepared was fabricated to 100 μm including the foil and used as the anode.

The cathode and the lithium-doped cathode are disposed in an aluminum case having a diameter of 18 mm and a height of 40 mm by applying the anode and the cathode manufactured in this way, and a separator for preventing a short circuit between the cathode and the anode between the anode and the cathode. Was placed in a winding type, and the electrolyte solution containing lithium salt was injected to impregnate the positive electrode and the negative electrode. The electrolyte was used to add 1M TEABF ₄ (tetraethylammonium tetrafluoborate) and 1M LiBF ₄ (lithium tetrafluoroborate) in propylene carbonate (PC) solvent. As the separator, TF4035 (manufactured by NKK, Japan) was used.

The operating voltage, capacitance, equivalent series resistance (ESR) of the hybrid supercapacitors thus prepared were measured, and the results are shown in Table 1 below.

The charge was carried out at 0.1 A for 120 minutes until the charge voltage, and the discharge was performed at 1 A at 0.1 A. Equivalent series resistance (ESR) was measured at 1 KHz.

3 is a graph showing a change in discharge capacitance according to a cycle of a hybrid supercapacitor manufactured according to the embodiment. In Figure 3 (a) is a case where the discharge capacitance according to the cycle was measured at a voltage of 2.3V, (b) is a case where the discharge capacitance according to the cycle is measured at a voltage of 2.5V, (c) is a 2.7V This is for the case where the discharge capacitance according to the cycle is measured by voltage.

Referring to FIG. 3, it can be seen that in both (a), (b), and (c), the same tendency of the discharge capacitance to decrease as the cycle increases. From this, it can be seen that the hybrid supercapacitor of the present invention manufactured according to the embodiment operates at an operating voltage of 2.7V as well as an operating voltage of 2.3V.

4 is a graph showing a change in current with time in a lithium doping process of a hybrid supercapacitor manufactured according to the embodiment.

It can be seen from FIG. 4 that the current consumption is reduced to less than 2 mA and the electrodeposition is mostly completed.

Comparative Example

A hybrid supercapacitor made by a conventional manufacturing method was used as this comparative example. That is, it compared with the 1840 (phi 18mm x 40mm) winding-type product which is a specification of 120F and 2.3V which lithium is not electrodeposited to an activated carbon electrode. The wound product shown as a comparative example uses the same winding, separator and electrolyte as in the above example.

In addition, operating voltage, capacity, and equivalent series resistance (ESR) were measured in the same manner as in the above example, and the results are shown in Table 1 below.

division Comparative example Example Working voltage (V) 2.3 2.7 Capacity (F) 120 150 Equivalent series resistance (mΩ) 20 20

As shown in Table 1, the hybrid supercapacitor of the present invention using the lithium-doped activated carbon electrode according to the embodiment as a cathode has a capacity of 25 even when using the same activated carbon as compared to the comparative example according to the prior art. It can be seen that the energy density is improved by 35% or more.

In addition, the ESR also shows the same value due to the electrode density improvement, and it can be seen that the energy density of the hybrid supercapacitor of the present invention has increased dramatically.

FIG. 5 is a graph showing a change in discharge capacitance according to a cycle of a hybrid supercapacitor according to an embodiment and a comparative example. In Figure 5 (a) shows the characteristics of the hybrid supercapacitor manufactured according to the embodiment is a case of measuring the discharge capacitance according to the cycle at a voltage of 2.7V, (b) is a characteristic of the hybrid supercapacitor according to the comparative example This is for the case of measuring the discharge capacitance according to the cycle with the voltage of 2.3V.

Referring to FIG. 5, it can be seen that in both (a) and (b), the same tendency of the discharge capacitance to decrease as the cycle increases. From this, it can be seen that the hybrid supercapacitor of the present invention manufactured according to the above embodiment is operated at an operating voltage of 2.7 V as well as an operating voltage of 2.3 V, and also at an operating voltage of 2.3 V even at an operating voltage of 2.7 V. It can be seen that it exhibits the same discharge capacitance characteristics as the hybrid capacitor according to the driven comparative example.

As mentioned above, although preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various deformation | transformation by a person of ordinary skill in the art within the scope of the technical idea of this invention is carried out. This is possible.

1 is a view showing a state for doping lithium into activated carbon.

2 is a graph showing time versus voltage characteristics for activated carbon and lithium.

3 is a graph showing a change in discharge capacitance according to a cycle of a hybrid supercapacitor manufactured according to an embodiment.

4 is a graph showing a change in current with time in a lithium doping process of a hybrid supercapacitor manufactured according to an embodiment.

5 is a graph showing a change in discharge capacitance according to a cycle of a hybrid supercapacitor according to an embodiment and a comparative example.

Claims (10)

An anode including a material capable of inserting or desorption of cations according to a charging or discharging operation; A negative electrode including activated carbon doped with lithium to lower the potential; A separator for preventing a short circuit between the positive electrode and the negative electrode; And Hybrid supercapacitor comprising an electrolyte solution in which lithium salt is dissolved between the positive electrode and the negative electrode. The method of claim 1, wherein the surface and the inside of the activated carbon is doped with lithium in accordance with the step of the pores formed in the activated carbon, and the insertion or desorption of lithium is performed on both the surface and the inside of the activated carbon in accordance with the charging or discharging operation A hybrid supercapacitor characterized by the above. The method of claim 1, wherein the anode comprises a lithium transition metal oxide, The lithium transition metal oxide is a complex metal oxide having a layered structure, a spinel structure, or an olivine structure containing lithium and a transition metal, and the transition metal is titanium (Ti), vanadium (V), manganese (Mn), iron ( Fe), cobalt (Co) and nickel is a hybrid supercapacitor, characterized in that at least one metal selected from the group consisting of. The method of claim 1, wherein the lithium salt, A hybrid supercapacitor comprising at least one salt selected from LiPF ₆ , LiBF ₄ , LiClO ₄ , Li (CF ₃ SO ₂ ) ₂ , LiCF ₃ SO ₃ , LiSbF _6, and LiAsF ₆ . The hybrid supercapacitor of claim 1, wherein the specific surface area of the activated carbon is in the range of 300 to 2200 m 2 / g. The method of claim 1, wherein the hybrid supercapacitor, Hybrid supercapacitor, characterized in that the operating voltage is equal to or greater than 2.5V. Arranging a working electrode including activated carbon and a counter electrode including a lithium foil to be spaced apart from each other, and injecting an electrolytic solution in which lithium salt is dissolved so that the working electrode and the counter electrode are impregnated; Applying a voltage of -0.1 V to 0.6 V on the working electrode; Doping and depositing lithium from the counter electrode and the lithium salt on the surface and the inside of the activated carbon; And A method of manufacturing a hybrid supercapacitor comprising the steps of preparing a hybrid supercapacitor using an activated carbon electrode including lithium-doped activated carbon as a cathode. The method of claim 7, wherein the manufacturing of the hybrid supercapacitor, A positive electrode including a lithium transition metal oxide, a negative electrode including activated carbon doped with lithium, and a potential lowered, a separator between the positive electrode and the negative electrode to prevent a short circuit between the positive electrode and the negative electrode, and the positive electrode and the negative electrode Injecting an electrolyte solution in which lithium salt is dissolved between the negative electrode, The positive electrode includes a step of preparing a mixture containing a lithium transition metal oxide by mixing a lithium transition metal oxide, a conductive material, a binder and a dispersion medium, and coating the mixture on a metal foil, the mixture is a lithium transition metal 100 parts by weight of oxide, 2 to 15 parts by weight of the conductive material and 2 to 10 parts by weight of the binder are added to 100 parts by weight of the lithium transition metal oxide, and the dispersion medium is more than 200 parts by weight based on 100 parts by weight of the lithium transition metal oxide. A method for producing a hybrid supercapacitor, characterized in that the addition of a large and less than 300 parts by weight. The method of claim 7, wherein the negative electrode comprises the steps of preparing an activated carbon mixture by mixing activated carbon, a conductive material, a binder and a dispersion medium, and coating the activated carbon mixture on a metal foil, wherein the activated carbon mixture is 100 parts by weight of activated carbon And 2 to 20 parts by weight of the conductive material and 2 to 10 parts by weight of the binder with respect to 100 parts by weight of activated carbon, and the dispersion medium is added in an amount of more than 200 parts by weight and less than 300 parts by weight with respect to 100 parts by weight of activated carbon. Method of manufacturing a hybrid supercapacitor, characterized in that. The method of claim 7, wherein the surface and the inside of the activated carbon are doped with lithium along the step of pores formed in the activated carbon, so that the insertion or desorption of lithium is performed on both the surface and the inside of the activated carbon according to a charging or discharging operation. Method for producing a hybrid supercapacitor

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