KR20140070180A - Slurry composition for preparing of electrode of redox flow battery and preparation method for electrode of redox flow battery - Google Patents

Abstract

The present invention relates to a slurry composition for manufacturing an electrode for a redox flow battery capable of increasing the lifetime of a battery by preventing the performance degradation of the battery for a long time operation, and providing an electrode having a uniform thickness and property; a manufacturing method of an electrode for a redox flow battery using the slurry composition; a carbon-based electrode including a dried product of the slurry composition for manufacturing an electrode for a redox flow battery; and a redox flow battery including the same.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a slurry composition for electrode production of a redox flow cell, and a method of manufacturing an electrode of a redox flow cell. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a slurry composition for electrode production of a redox flow cell and a method of manufacturing an electrode of redox flow battery. More particularly, the present invention relates to a slurry composition for electrode production of a redox flow cell capable of preventing deterioration of the battery performance even during long-term operation and thereby increasing the service life of the battery and providing an electrode having uniform thickness and physical properties, To a method of manufacturing an electrode of a redox flow cell.

Existing power generation systems, such as thermal power generation using nuclear fossil fuels and large-scale greenhouse gas and environmental pollution problems, and nuclear power generation, which have the problems of stability of the facility itself or waste disposal problems, have various limitations and are more environmentally friendly and highly efficient Research on the development of energy and the development of power supply system using it has been greatly increased.

Particularly, the power storage technology makes it possible to utilize renewable energy which is greatly influenced by external conditions in a wider and wider range, and the efficiency of power utilization can be further increased. And research and development have been increasing.

The redox flow cell is an oxidation / reduction cell that can convert the chemical energy of the active material directly into electrical energy. It stores renewable energy with high output fluctuation depending on the external environment such as sunlight and wind power and converts it into high quality power Energy storage system. Specifically, in the redox flow cell, the electrolyte containing the active material causing the oxidation / reduction reaction circulates between the opposite electrode and the storage tank, and charging / discharging proceeds.

The redox flow cell basically includes a tank storing different active materials in oxidation states, a pump circulating the active material during charging / discharging, and a unit cell divided into a separation membrane. The unit cell includes an electrode, an electrolyte, and a separation membrane do.

Electrodes, one of the components that have the greatest influence on the cell performance of the chemical flow cell, are manufactured by coating carbon plastic having a large reaction area on the conductive plastic sheet in order to maximize the redox reaction.

However, in the method of applying the adhesive binder on a predetermined sheet and coating the carbon compound powder, the powder of the carbon compound may not be uniformly applied. In order to fix the carbon compound powder, a thermocompression process is performed, And there is a limit in that the thermocompression-bonded carbon compound powder may be peeled off at a later stage to deteriorate the performance of the battery.

In addition, spraying, rolling, brushing, or the like has been used to more uniformly apply the carbon compound powder. However, it is difficult to apply the method to mass production of the electrode, and the amount of the carbon compound powder applied varies There is a variation in performance between the batteries. Also, the battery manufactured by applying the above method exhibits a phenomenon in which the carbon compound powder is peeled off from the electrode layer, thereby deteriorating the performance of the battery.

Accordingly, there is a need to develop a method for manufacturing an electrode layer having uniform thickness and physical properties, which can increase the lifetime of a battery by minimizing carbon peeling at the time of long-term driving.

Disclosed herein is a slurry composition for electrode fabrication of a redox flow cell capable of preventing deterioration in performance of a battery even during long-term operation to increase the lifetime of the battery and to produce an electrode layer having uniform thickness and physical properties.

The present invention also provides a method of manufacturing an electrode of a redox-flow cell using the slurry composition.

The present invention also provides a redox flow cell including a carbon-based electrode manufactured using the slurry composition.

The present invention relates to a powder of a carbon compound; Binder resin; Hydrophobic organic solvent; And a dispersant. The present invention also provides a slurry composition for electrode production of a redox flow cell.

The present invention also provides a method of manufacturing an electrode of a redox flow cell comprising coating the slurry composition on a substrate.

The present invention also provides a redox flow cell including a carbon-based electrode prepared using the slurry composition.

Hereinafter, a slurry composition for preparing an electrode of a redox flow cell, a method of manufacturing an electrode of redox flow battery, and a redox flow battery according to a specific embodiment of the present invention will be described in detail.

According to one embodiment of the invention, a powder of a carbon compound; Binder resin; Hydrophobic organic solvent; And a dispersing agent, can be provided.

The present inventors have found that a powder of a carbon compound; Binder resin; Hydrophobic organic solvent; And a dispersant may be coated on a predetermined substrate to produce an electrode of a redox flow cell. In addition to being able to have uniform thickness and physical properties in the whole area of the electrode to be manufactured, It is possible to obtain uniform performance of each of the final products and minimize the phenomenon that the carbon compound or the like is peeled off from the electrode layer even when the slurry composition is manufactured using the slurry composition of a specific composition for a long period of time, The points were confirmed through experiments and the invention was completed.

Said slurry composition comprising a powder of a carbon compound; Binder resin; Hydrophobic organic solvent; And a dispersing agent can be obtained by forming a slurry phase using a commonly used mixing method. The mixing method that can be used at this time is not limited to a wide range. For example, a homogenizer or a stirrer may be used to stir at high speed, or a screw may be used for a dissolver, a roll may be passed through a gap of the roll, A slurry having a uniform composition can be formed by using a ball mill used, an agitator mill using an impact between particles, or an ultrasonic mixer.

A powder of the carbon compound; Binder resin; Hydrophobic organic solvent; And the dispersing agent are not limited, and the slurry composition may be prepared by adding or mixing the components in various order. For example, the carbon compound powder, the binder resin, and the hydrophobic organic solvent may be stirred at a high speed to prepare a mixture, and a dispersant may be added thereto. The hydrophobic organic solvent and the dispersant are mixed, A binder resin may be added and stirred at a high speed.

The composition obtained by mixing and stirring the above-described components may be in a slurry form, and such a slurry composition may comprise particles having an average particle size of from 10 to 200 mu m. The binder resin may be bonded to the powder of the carbon compound by the functional group of the dispersing agent or the dispersing agent and may be uniformly dispersed in the hydrophobic organic solvent so that the uniformly dispersed slurry phase and the particles having the average particle size may be formed have.

The slurry composition for electrode preparation of the redox flow cell may have a viscosity of 500 to 10,000 cps, preferably 1,000 to 7,000 cps.

The powder of the carbon compound preferably has a high electrical conductivity to allow the electrode formed from the slurry composition to flow in or out more effectively. Specific examples of such carbon compounds include graphite, penn carbon fibers, pitch carbon fibers, activated carbon, amorphous carbon, and mixtures of two or more thereof. Examples of commercially available powders of such carbon compounds include graphite (SG Company, GFG5) penned carbon fiber (GEFC Carbon Felt), activated carbon (OC), and amorphous carbon (Mitsubishi 300J).

The powder of the carbon compound may have a maximum diameter of 5 占 퐉 to 100 占 퐉 in order to realize more uniform and improved physical properties and electrical conductivity in the electrode which is more uniformly dispersed and produced in the slurry composition.

The binder resin binds the powder of the carbon compound contained in the electrode and forms a base material of the electrode. Specific examples of the binder resin include perfluoropolymers, benzimidazole-based polymers, polyimide-based polymers, polyetherimide-based polymers, polyphenylene sulfide-based polymers, polysulfone-based polymers, polyether sulfone-based polymers, Ketone-based polymers, polyether-ether ketone-based polymers, polyterylquinoxaline-based polymers, or mixtures of two or more thereof.

The hydrophobic organic solvent can more easily dissolve the powder of the carbon compound having the hydrophobic property and the binder resin, and can uniformly mix and disperse it to have the above-described slurry characteristic. Specific examples of the hydrophobic organic solvent include toluene, xylene, N-methylpyrrolidone, dimethylsulfoxide, dimethylacetate, or a mixture of two or more thereof.

The dispersant allows each component of the slurry composition to be more uniformly dispersed and distributed to form a dispersion or slurry phase. Specific examples of such dispersants include nonionic surfactants, silicone antifoaming agents, modified urea blends, and silicone surfactants.

Surfynol 440, Surfynol 420, Surfynol 61, Triton X-100, Tween 20, and the like can be given as nonionic surfactants that can be used as the dispersant. Examples of the silicone antifoaming agent include BYK-024 and the like. Examples of the modified urea blend include products such as BYKETOL-PC. Specific examples of the silicone surfactant include products such as DISPERBYK®-162.

Meanwhile, in the slurry composition for electrode production of the redox-flow battery, the content of the above-mentioned components can be controlled according to the characteristics of the slurry to be produced and the characteristics of the electrode. For example, the slurry composition for electrode preparation of the redox flow cell may comprise 1 to 90% by weight of a powder of a carbon compound; 1 to 90% by weight of a binder resin; 1 to 90% by weight of a hydrophobic organic solvent; And 0.1 to 30% by weight of a dispersing agent.

According to another embodiment of the present invention, there is provided a method of manufacturing an electrode of a redox flow cell, which comprises coating a slurry composition for electrode production of the redox flow cell on a substrate.

As described above, the electrode of the redox flow cell can be produced by applying the slurry composition having the specific composition on a predetermined substrate. In addition to being able to have uniform thickness and physical properties in all regions, It is possible to minimize the phenomenon that the carbon compound or the like is peeled from the electrode layer even when the battery is used for a long period of time, .

The slurry composition for electrode preparation of the redox-flow battery may be applied on the substrate to a thickness of 5 to 200 탆.

The substrate is a support for a slurry composition to be applied, and can be removed if a solid state electrode is formed through a process such as drying. Examples of such substrates are not limited, and various conductive plastic sheets, organic substrates (such as polymer substrates), inorganic substrates (such as metal substrates), glass substrates, and organic substrates such as fibers and woods can be used.

The coating of the slurry composition may be carried out using various coatings or coating methods known in the art. For example, a slot die coater, a comma coater, a blade coater, a gravure coater, a bar coater, or a lip coater may be used.

Meanwhile, the method for manufacturing the electrode of the redox-flow battery may further include drying the coated slurry composition. The method, apparatus or temperature conditions that can be used in such a drying step are not particularly limited, and a method of heating with a predetermined heat source, a method of ventilation, a method of drying at a room temperature or a low temperature, and the like can be used variously.

And, in order to ensure more uniform application and uniformity of the slurry composition, the method of manufacturing the electrode of the redox-flow battery may further include defoaming the slurry composition.

According to another embodiment of the present invention, there is provided a redox flow cell including a carbon-based electrode manufactured using the slurry composition for electrode preparation of the redox flow cell.

According to another embodiment of the present invention, a redox flow cell including a carbon-based electrode including a dried slurry composition for electrode production of the redox flow cell may be provided.

Wherein the redox flow cell comprises: a tank in which different active materials having different oxidation states are stored; A pump for circulating the active material during charging / discharging; And a unit cell divided into an electrode, an electrolyte, and a separator. The unit cell may include the carbon-based electrode, the electrolyte, and the porous separator.

According to the present invention, there is provided a slurry composition for electrode production of a redox flow cell, which can provide an electrode having uniform thickness and physical properties, which can increase the service life of the battery by preventing deterioration of battery performance even during long- , A carbon-based electrode including a dried product of the slurry composition for electrode preparation of the redox-flow battery, and a redox-flow battery including the redox-flow battery.

1 is a schematic view showing the structure of a redox flow cell.
Fig. 2 is a diagram comparing the thickness deviations of the electrode and the commercial electrode obtained in Example 2. Fig.
FIG. 3 is a graph comparing the loading values (mg / cm 2) of the electrodes obtained in Example 2 and commercial electrodes.
Fig. 4 shows the results of measurement of the performance-maintaining ability of the carbon electrode and the commercial electrode (ZBB, Electrode) obtained in Example 2. Fig.

The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

[ Example 1 : Redox  Manufacture of electrode for flow cell Slurry  Preparation of the composition]

10 g of activated carbon (OC, Samchully Carbotheque, maximum diameter: 74 탆) and 10.38 g of a binder solution (polypropylene, 747 MH, 20% by weight, Zenchem) were added to 28 g of a dispersion medium (toluene, Aldrich) Branson), and 0.5 g of a dispersant (DISPERBYK®-162) was added and mixed for 30 minutes to prepare a slurry composition (viscosity of 2,500 cps).

It was confirmed that the average particle size of the particles measured by filling the slurry into a grind gauge was distributed in a range of at least 20 μm to a maximum of 200 μm.

[ Example 2 : Redox  Electrode fabrication of flow cell]

The slurry composition of Example 1 was coated on a conductive plastic sheet (Electrode, ZBB) to a thickness of 100 mu m using a bar-coater (Dongyang ENG). The coated carbon slurry was dried at 80 ° C for 30 minutes to allow the binder resin to have crystallinity, and then cooled to room temperature to prepare a carbon electrode.

[ Experimental Example : Evaluation of Physical Properties of Electrode]

Experimental Example 1 : Measurement of electrode thickness and loading deviation

The thickness and loading value (mg / cm 2) of the coating layer were measured at 10 points of the carbon electrode and the commercial electrode (ZBB, Electrode) obtained in Example 2, and the deviations were compared.

The results of measuring the thickness and loading of the carbon electrode and the commercial electrode of Example 2 are shown in Table 1 below.

Measurement results of thickness and loading Measuring position Thickness measurement result (탆) Loading measurement result (mg / cm2) Example 2 Used electrode Example 2 Used electrode One 1022 1050 2.4 1.2 2 1016 993 2 2.8 3 1015 1016 1.9 2.2 4 1009 1011 2.2 1.3 5 1029 992 2.1 1.9 6 1008 996 2.2 2.1 7 1015 1034 1.8 2 8 1014 1011 2 2.6 9 1027 999 2.1 2.1 10 1012 997 2.1 2.3 medium 1016.7 1009.9 2.08 2.05 Standard Deviation 7.12 19.19 0.17 0.50

As shown in Table 1, FIG. 2 and FIG. 3, it was confirmed that the carbon electrode obtained in Example 2 had a more uniform thickness and loading value than the commercial electrode.

Experimental Example 2 : Measurement of performance maintenance capability during long-term operation

A zinc-bromodeoxane flow cell was fabricated using the carbon electrode obtained in Example 2 and a commercial electrode (ZBB, Electrode). The cell was driven at least 50 times and the energy efficiency was measured.

As can be seen from FIG. 4, it was confirmed that the carbon electrode obtained in Example 2 was not much lowered in energy efficiency during long-term operation than the commercial electrode, and thus had a higher performance maintenance capability.

Claims (15)

Powder of carbon compound;
Binder resin;
Hydrophobic organic solvent; And
A slurry composition for electrode production of redox flow cells, comprising a dispersant.
The method according to claim 1,
Wherein the particles contained in the slurry have an average particle size of 10 to 200 占 퐉.
The method according to claim 1,
And a viscosity of 500 to 10,000 cps.
The method according to claim 1,
Wherein the carbon compound comprises at least one member selected from the group consisting of graphite, pellet carbon fiber, pitch carbon fiber, activated carbon and amorphous carbon.
The method according to claim 1,
Wherein the powder of the carbon compound has a maximum diameter of 5 mu m to 100 mu m.
The method according to claim 1,
The binder resin may be at least one selected from the group consisting of perfluorinated polymers, benzimidazole polymers, polyimide polymers, polyetherimide polymers, polyphenylene sulfide polymers, polysulfone polymers, polyether sulfone polymers, polyether ketone polymers, A polyether-ether ketone-based polymer, and a polyether-quinoxaline-based polymer.
The method according to claim 1,
Wherein the hydrophobic organic solvent comprises at least one selected from the group consisting of toluene, toluene, xylene, N-methylpyrrolidone, dimethylsulfoxide, and dimethyl acetate.
The method according to claim 1,
Wherein the dispersant comprises at least one compound selected from the group consisting of a nonionic surfactant, a silicone antifoaming agent, a modified urea combination, and a silicone surfactant.
The method according to claim 1,
1 to 90% by weight of a powder of a carbon compound;
1 to 90% by weight of a binder resin;
1 to 90% by weight of a hydrophobic organic solvent; And
And 0.1 to 30% by weight of a dispersant.
10. A method of manufacturing an electrode of a redox flow cell, comprising the step of coating the slurry composition of any one of claims 1 to 9 onto a substrate.
11. The method of claim 10,
Wherein the coating thickness of the composition is 5 to 200 占 퐉.
11. The method of claim 10,
Wherein the coating of the slurry composition uses a slot die coater, a comma coater, a blade coater, a gravure coater, a bar coater, or a lip coater.
11. The method of claim 10,
And drying the coated slurry composition. ≪ Desc / Clms Page number 20 >
11. The method of claim 10,
Further comprising defoaming the slurry composition. ≪ RTI ID = 0.0 > 11. < / RTI >
A redox flow cell comprising a carbon-based electrode prepared using the slurry composition of any one of claims 1 to 9.

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