KR20200117343A - Flow battery having excellent charge and discharge characteristics - Google Patents

Abstract

The present invention relates to a flow battery in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell comprising a positive electrode, a negative electrode, and a separator disposed between a positive electrode current collector and a negative electrode current collector to perform charging and discharging, wherein the positive electrode electrolyte comprises Mn(phen)_3X_n (″phen″ is ″1,10-phenanthroline″, n is a natural number of 1 or 2, and X is at least one anion selected from SO^-2_4, NO^-_3, Cl^-, Br ^- I^-, BF^-_4 and PF^-_6). In addition, the flow battery of the present invention has excellent charge/discharge properties and output capacity properties.

Description

Flow battery having excellent charge and discharge characteristics

The present invention relates to a flow battery, and more particularly, Mn (phen) ₃ X _n (where "phen" is "1,10-phenanthroline", n is a natural number of 1 or 2, and X is an anion). It relates to a flow battery that uses a positive electrode active material and has excellent output capacity characteristics.

The flow battery is an energy storage material, and contains redox materials (redox pairs) capable of redox, and is made in the form of a solution to accumulate or release energy while flowing from the flow battery.

Flow batteries are attracting attention as batteries suitable for large-capacity energy storage. However, due to its low energy density, it requires 2-3 times the volume of lithium secondary batteries.

The energy storage material of the current commercially available flow battery generally uses water-based vanadium ions, and as an electrolyte, hydrogen ions (H ⁺ ) are used as charged ions. Such a vanadium-based flow battery theoretically generates a voltage of about 1.2V, and since it is an aqueous solution, it has high ionic conductivity and has excellent output, and has excellent safety because it does not use a flammable solvent. However, there is a disadvantage of low energy density that can be stored due to the low voltage. The flow battery stores energy for a long period of time, so it is equipped with large-sized devices, and because it is a building-type device, it is less constrained by space, but a low energy density means a large-scale facility, thus increasing the size of the building. This is a high energy density, which contrasts with lithium secondary batteries that can be applied to storage for various purposes.

Vanadium-based flow battery using four oxidation states of vanadium maintains the life of the membrane for the longest, so it has good durability even when the battery is used for 10-20 years. However, since the voltage is low, not only the energy density is low, as mentioned above, but also the maximum output value is lowered. In addition, since the vanadium-based flow battery is under a strong acidic condition, the electrode is gradually corroded, which can shorten the lifespan and reduce the output.

Korean Patent Publication No. 10-1509581

The problem to be solved by the present invention is to provide a flow battery having excellent output capacity characteristics.

The present invention is a flow battery in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode, a negative electrode, and a separator disposed between the positive electrode current collector and the negative electrode current collector to perform charging and discharging, wherein the positive electrode electrolyte comprises: Mn in the positive electrode active material (phen) ₃ X _n (where, "phen" is the "1,10-phenanthroline", n is a natural number of 1 or 2, X is ^{_{SO 4 2-, NO 3 -,}} Cl -, Br ^- I ^-, BF ₄ ^- and provides a flow cell comprising the one or more anions selected from a) ^-, and PF _6.

The positive electrode electrolyte may further include a supporting electrolyte, and the supporting electrolyte is an electrolyte including a cation and an anion, and the cation of the supporting electrolyte is a quaternary ammonium ion, a high molecular weight ammonium ion, a lithium ion, a sodium ion, a hydrogen ion, and may comprise one or more cations selected from potassium ion, the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F - _{^{, I 2 Br -, Br 2}} I -, NO 3 -, SO 4 2-, PF 6 -, ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, ( ^{_{CF 3 SO 2) 2 N -}} , (C 2 F 5 SO 2) 2 N -, (CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- It may contain one or more anions selected from among. It is preferable that the supporting electrolyte has a concentration of 0.05 to 5M.

The negative electrode electrolyte may include 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride as a negative electrode active material.

It is preferable that the positive electrode active material has a concentration of 0.01 to 5.0 M.

It is preferable that the negative electrode active material has a concentration of 0.01 to 5.0 M.

The negative electrode electrolyte may further include a supporting electrolyte, and the supporting electrolyte is an electrolyte including a cation and an anion, and the cation of the supporting electrolyte is a quaternary ammonium ion, a high molecular weight ammonium ion, a lithium ion, a sodium ion, a hydrogen ion, and may comprise one or more cations selected from potassium ion, the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F - _{^{, I 2 Br -, Br 2}} I -, NO 3 -, SO 4 2-, PF 6 -, ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, ( ^{_{CF 3 SO 2) 2 N -}} , (C 2 F 5 SO 2) 2 N -, (CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- It may contain one or more anions selected from among. It is preferable that the supporting electrolyte has a concentration of 0.05 to 5M.

The positive electrode electrolyte and the negative electrode electrolyte may include an aqueous solvent that dissociates the electrolyte.

The positive electrode and the negative electrode may include carbon felt having electrical conductivity.

The carbon felt may be a felt activated at 300 to 550°C.

It is preferable that the cathode active material has a higher redox potential than the anode active material.

The positive electrode active material may include a derivative represented by the following structural formula.

[constitutional formula]

Wherein G includes at least one functional group selected from the group consisting of nitro, cyan, methyl, ethyl, propyl, isopropyl and butyl,

X is SO ₄ ^2-, NO ₃ ^- comprises at least one anion selected from the group consisting of ^{-, Cl -, Br - I} -, BF 4 - and PF _6.

According to the flow battery of the present invention, a positive electrode active material containing Mn(phen) ₃ X _n (where "phen" is "1,10-phenanthroline", n is a natural number of 1 or 2, and X is an anion) It is used and a negative electrode active material containing 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride is used, and has excellent charge/discharge characteristics and output capacity characteristics.

1 is a view schematically showing a flow battery according to the present invention.
2 to 4 are photographs of the battery cells used in the experimental example.
5 is a cross-sectional view illustrating a method of assembling a battery cell.
6 is a front view showing the outer case of the battery cell.
7 is a side view showing an outer case of the battery cell.
8 is a plan view showing an outer case of the battery cell.
9 is a front view showing the cover of the battery cell.
10 is a side view showing the cover of the battery cell.
11 is a plan view showing a cover of a battery cell.
12 is a graph showing a measurement result of a charge/discharge curve using an active material.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments are provided so that the present invention may be sufficiently understood by those of ordinary skill in the art, and may be modified in various other forms, and the scope of the present invention is limited to the embodiments described below. It does not become.

In the detailed description of the invention or in the claims, when any one component "includes" another component, it is not construed as being limited to consisting of only the component unless otherwise stated, and other components are further included. It should be understood that it may contain.

A flow battery according to a preferred embodiment of the present invention is a flow in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode, a negative electrode, and a separator disposed between the positive electrode current collector and the negative electrode current collector to perform charging and discharging. In the battery, the positive electrode electrolyte is Mn (phen) ₃ X _n as a positive electrode active material (here, "phen" is "1,10-phenanthroline", n is a natural number of 1 or 2, and X is SO ₄ ^2- , comprises at least one selected from ^{_{anions) - NO 3 -, Cl -}} , Br - I -, BF 4 - and PF _6.

The positive electrode electrolyte may further include a supporting electrolyte, and the supporting electrolyte is an electrolyte including a cation and an anion, and the cation of the supporting electrolyte is a quaternary ammonium ion, a high molecular weight ammonium ion, a lithium ion, a sodium ion, a hydrogen ion, and may comprise one or more cations selected from potassium ion, the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F - _{^{, I 2 Br -, Br 2}} I -, NO 3 -, SO 4 2-, PF 6 -, ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, ( ^{_{CF 3 SO 2) 2 N -}} , (C 2 F 5 SO 2) 2 N -, (CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- It may contain one or more anions selected from among. It is preferable that the supporting electrolyte has a concentration of 0.05 to 5M.

The negative electrode electrolyte may include 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride as a negative electrode active material.

It is preferable that the positive electrode active material has a concentration of 0.01 to 5.0 M.

It is preferable that the negative electrode active material has a concentration of 0.01 to 5.0 M.

The negative electrode electrolyte may further include a supporting electrolyte, and the supporting electrolyte is an electrolyte including a cation and an anion, and the cation of the supporting electrolyte is a quaternary ammonium ion, a high molecular weight ammonium ion, a lithium ion, a sodium ion, a hydrogen ion, and may comprise one or more cations selected from potassium ion, the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F - _{^{, I 2 Br -, Br 2}} I -, NO 3 -, SO 4 2-, PF 6 -, ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, ( ^{_{CF 3 SO 2) 2 N -}} , (C 2 F 5 SO 2) 2 N -, (CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- It may contain one or more anions selected from among. It is preferable that the supporting electrolyte has a concentration of 0.05 to 5M.

The positive electrode electrolyte and the negative electrode electrolyte may include an aqueous solvent that dissociates the electrolyte.

The positive electrode and the negative electrode may include carbon felt having electrical conductivity.

The carbon felt may be a felt activated at 300 to 550°C.

It is preferable that the cathode active material has a higher redox potential than the anode active material.

The positive electrode active material may include a derivative represented by the following structural formula.

[constitutional formula]

Wherein G includes at least one functional group selected from the group consisting of nitro, cyan, methyl, ethyl, propyl, isopropyl and butyl,

X is SO ₄ ^2-, NO ₃ ^- comprises at least one anion selected from the group consisting of ^{-, Cl -, Br - I} -, BF 4 - and PF _6.

Hereinafter, a flow battery according to a preferred embodiment of the present invention will be described in more detail.

Flow batteries are attracting attention as batteries suitable for large-capacity energy storage. However, due to its low energy density, it requires 2-3 times the volume of lithium secondary batteries. In order to improve the energy density, it is necessary to develop a redox pair compared with a flow battery using an existing aqueous solution.

The problem with redox pairs for non-aqueous solvents is a low reaction rate (low current) with low solubility. The low solubility and low current directly affect not only the energy storage but also the output of the battery, thus acting as a direct barrier to the study of redox pairs for non-aqueous solvents.

In the present invention, a positive electrode active material containing Mn (phen) ₃ X _n (here, "phen" is "1,10-phenanthroline", n is a natural number of 1 or 2, and X is an anion), and output capacity characteristics We present this excellent flow battery.

1 is a view schematically showing a flow battery according to the present invention.

Referring to FIG. 1, the flow battery includes a positive electrode electrolyte 140 in a battery cell including a positive electrode 110, a negative electrode 120, and a membrane 130 disposed between the positive electrode 110 and the negative electrode 120. And the cathode electrolyte 150 is supplied to perform charging and discharging. The anode 110 and the cathode 120 may be connected to a power supply through a wire.

The flow battery includes a positive electrode cell 115 including a positive electrode 110 and a positive electrolyte solution 140, a negative electrode cell 125 including a negative electrode 120 and a negative electrode electrolyte 150, and a positive electrode cell 115 and a negative electrode. Separating the cell 125 and including an isolation film 130 for permeating ions. The positive cell 115, the negative cell 125, and the separator 130 constitute a battery cell. The flow battery may be formed by connecting or stacking a plurality of such battery cells.

A first tank 155 for supplying the anode electrolyte 140 may be connected to the anode cell 115 through conduits 160 and 165. A second tank 170 for supplying the cathode electrolyte 150 may be connected to the cathode cell 125 through conduits 175 and 180. A pump (not shown) for circulating the positive electrolyte solution 140 may be provided in the conduit 160, and a pump (not shown) for circulating the negative electrolyte solution 150 may be provided in the conduit 175.

The anode electrolyte 140 contained in the first tank 155 is supplied to the anode cell 115 through a conduit 160, and the anode electrolyte 140 supplied to the anode cell 115 is supplied through the conduit 165. It is discharged and is introduced into the first tank 155. The cathode electrolyte 150 contained in the second tank 170 is supplied to the cathode cell 125 through a conduit 175, and the cathode electrolyte 150 supplied to the cathode cell 125 is discharged through the conduit 180 And is introduced into the second tank 170. In this way, the positive electrolyte 140 and the negative electrolyte 150 are supplied to be circulated, and charging and discharging are performed while the positive electrolyte 140 and the negative electrolyte 150 flow in the flow battery.

The positive electrode electrolyte 140 contains a positive electrode active material, the negative electrode electrolyte 150 contains a negative electrode active material, and the positive electrode electrolyte 140 may contain an aqueous solvent that dissociates the positive electrode active material, and the negative electrode electrolyte 150 It may also include an aqueous solvent that dissociates the negative active material. It is preferable that the cathode active material has a higher redox potential than the anode active material.

The positive electrode active material is Mn (phen) ₃ X _n (where, "phen" is "1,10-phenanthroline", n is a natural number of 1 or 2, X is ^{_{SO 4 2-, NO 3 -,}} Cl -, comprises at least one selected from ^{anions) - Br - I -, BF} 4 - and PF _6. An example of the positive electrode active material is Mn(phen) ₃ SO ₄ (Tris(1,10-phenanthroline) manganese(II) sulfate).

An example of a method of manufacturing the Mn(phen) ₃ X _n will be described. MnX MnX _n or _n hydrate (where, n is a natural number of 1 or 2, X is ^{_{SO 4 2-, NO 3 -,}} Cl -, Br - I -, BF 4 - and PF ₆ ^- one or more kinds selected from the group consisting of anionic ) Is dissolved in a solvent such as distilled water, and 1,10-phenanthroline monohydrate is dissolved in a solvent such as ethanol, mixed with the solution in which the MnX _n or MnX _n hydrate is dissolved, stirred, and the resulting mixture is distilled under reduced pressure to remove the solvent. , Precipitated using acetone, etc., and then filtered under reduced pressure to obtain Mn(phen) ₃ X _n .

As an example of a cathode active material, the schematic structure of Mn(phen) ₃ SO ₄ (Tris(1,10-phenanthroline) manganese(II) sulfate) is shown in Structural Formula 1 below.

[Structural Formula 1]

A method of preparing the Mn(phen) ₃ SO ₄ (Tris(1,10-phenanthroline) manganese(II) sulfate) will be described in detail by way of example. MnSO ₄ hydrate (e.g., MnSO ₄ H ₂ O) was dissolved in a solvent such as distilled water, 1,10-phenanthroline monohydrate was dissolved in a solvent such as ethanol, and then mixed with a solution of MnSO ₄ hydrate and stirred, and the resulting agitation was After distillation under reduced pressure to remove the solvent, precipitation with acetone or the like, and then filtration under reduced pressure to obtain Mn(phen) ₃ SO ₄ .

The cathode active material may include a derivative represented by the following structural formula 2.

[Structural Formula 2]

Here, G is a symbol denoting a functional group, and G may include one or more functional groups selected from the group consisting of nitro, cyan, methyl, ethyl, propyl, isopropyl, and butyl, and G is the maximum per molecule. Up to 4 substitutions are possible.

X is SO ₄ ^2-, NO ₃ ^- it may include one or more anions selected from the group consisting of ^{-, Cl -, Br - I} -, BF 4 - and PF _6.

The negative active material may include 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride (Neutral Red). The schematic structure of the 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride is shown in Structural Formula 3 below.

[Structural Formula 3]

The positive electrode electrolyte 140 may further include a supporting electrolyte. The supporting electrolyte is an electrolyte that is put into the electrolyte to increase the electrical conductivity of the electrolyte without electrolysis. The supporting electrolyte is an electrolyte containing a cation and an anion, and the cation of the supporting electrolyte includes at least one cation selected from quaternary ammonium ions, high molecular weight ammonium ions, lithium ions, sodium ions, hydrogen ions and potassium ions, and the the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F -, I 2 Br -, Br 2 I -, NO 3 -, _{^{SO 4 2-, PF 6 -,}} ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO ^{_{2) 2 N -, (CF}} 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- may comprise one anion or more species selected from, the supporting electrolyte It is preferable to have a concentration of 0.05 to 5M.

The cathode electrolyte 150 may further include a supporting electrolyte. The supporting electrolyte is an electrolyte that is put into the electrolyte to increase the electrical conductivity of the electrolyte without electrolysis. The supporting electrolyte is an electrolyte containing a cation and an anion, and the cation of the supporting electrolyte includes at least one cation selected from quaternary ammonium ions, high molecular weight ammonium ions, lithium ions, sodium ions, hydrogen ions and potassium ions, and the the anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F -, I 2 Br -, Br 2 I -, NO 3 -, _{^{SO 4 2-, PF 6 -,}} ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO ^{_{2) 2 N -, (CF}} 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- may comprise one anion or more species selected from, the supporting electrolyte It is preferable to have a concentration of 0.05 to 5M.

The quaternary ammonium ion is in the nitrogen atom R ₁ , R ₂ , R ₃ , R ₄ alkyl group (R ₁ , R ₂ , R ₃ and R ₄ are methyl, ethyl, propyl, isopropyl, butyl, isobutyl A group, a pentyl group, a hexyl group, a cyclohexyl group or a benzyl group) may include a quaternary ammonium ion (R ₁ R ₂ R ₃ R ₄ N ⁺ ) including. R ₁ , R ₂ , R ₃ and R ₄ may be identical to each other or may be heterogeneous alkyl groups.

The polymeric ammonium ion may be a chain-linked ammonium ion.

As a specific example of such a supporting electrolyte, H ₂ SO ₄ , HNO ₃ , HCl, HBr, HI, HBF ₄ , HPF ₆ , HN ₄ SO ₄ , HN ₄ NO ₃ , HN ₄ Cl, HN ₄ Br, HN ₄ I aqueous solution Or a mixture of these, etc. are mentioned. It is preferable that the concentration of the aqueous solution used as the supporting electrolyte is about 0.05 to 5.0 M.

The positive electrode active material used in the positive electrode electrolyte preferably has a concentration of 0.01 to 5.0 M, and the negative electrode active material used in the negative electrode electrolyte preferably has a concentration of 0.01 to 5.0 M.

The positive electrode electrolyte 140 and the negative electrolyte 150 include an aqueous solvent that dissociates the electrolyte, and the aqueous solvent may be a solvent containing water (H ₂ O).

The positive electrode electrolyte 140 is supplied so that the positive electrode 110 is wetted, and the negative electrode electrolyte 150 is supplied so that the negative electrode 120 is wetted.

As the anode 110 and the cathode 120, a flat plate type, a grid-shaped mesh type, and a sponge-shaped felt type may be used. For example, the anode 110 and the cathode 120 include conductive metals such as Au, Pt, Ni, etc., conductive metal composites including metals such as Au, Pt, Ni, and conductive polymers such as polyacetylene and polythiophene. , Felts having electrical conductivity, such as nickel felt, carbon felt, and graphite felt, which have high specific surface area and are relatively inexpensive and have excellent electrical conductivity, can be used. In particular, carbon felt, which is a carbon material, has excellent stiffness and electrical conductivity, and can help with durability and output. It is preferable that the carbon felt is a felt activated at 300 to 550°C.

The membrane 130 disposed between the anode 110 and the cathode 120 may be formed of an anion exchange membrane or a zwitterion exchange membrane. For example, Nafion has strong mechanical rigidity and high alkali resistance, and can be used as a separator having anion selectivity.

The flow battery according to the present invention described above has the advantage of being able to construct in a short time due to a simple structure of a battery and a simple installation. In addition, the flow battery is suitable for an energy storage device that can be used for a long time because it can be easily repaired because only the stack needs to be replaced when a single stack malfunctions. Accordingly, there is a high possibility that it can be used as a buffer power in case of a power outage in chemical plants, internet data centers (IDCs), and semiconductor companies that require the stability of power in the industry. In addition, it is highly likely to be used as a replacement for a pumped-up power plant that was difficult to construct due to environmental damage. In addition, as a facility that stores power produced in new and renewable energy power generation complexes in which the quality of power is not constant and outputs power with uniform quality, it can be constructed in various sizes. It is expected that large-scale facilities of flow cells that can utilize organic solvents will be possible because it is a mountainous area without private facilities or a sea.

In the following, the experimental examples according to the present invention are specifically presented, and the present invention is not limited to the experimental examples presented below.

<Experimental Example>

1. Preparation of supporting electrolyte solution

A 1M sulfuric acid solution was used as the supporting electrolyte. After weighing 5.61 ml of sulfuric acid (Samchun pure Chem. co., 95%), put it in a 100 ml volumetric flask and add water (H ₂ O) to the 100 ml mark to prepare a sulfuric acid solution, and the sulfuric acid solution as a supporting electrolyte Used.

2. Preparation of electrode active material solution

Mn(phen) ₃ SO ₄ ) (Tris(1,10-phenanthroline) manganese(II) sulfate) used as a positive electrode active material was synthesized through the following process.

MnSO ₄ ·H ₂ O (Alfa aesar. co., 99%) 5 mmol was weighed and dissolved in distilled water. After weighing 4 equivalents of 1,10-phenanthroline monohydrate (Samchun pure Chem. co., 99%) and dissolving in ethanol, the mixture was stirred for 2 hours in a solution in which MnSO ₄ ·6H ₂ O was dissolved. The resulting mixture was distilled under reduced pressure to remove the solvent, precipitated with 200 ml of Acetone (Daejung Chem. co., 99.5%) and filtered under reduced pressure to obtain Mn(phen) ₃ SO ₄ . The reaction as described above is shown in Scheme 1 below.

[Scheme 1]

The Mn(phen) ₃ SO ₄ was weighed in an amount corresponding to 0.1 M and placed in a 10 ml volumetric flask, and the supporting electrolyte was added up to the 100 ml mark to prepare a positive electrode electrolyte.

3-Amino-7-dimethylamino-2-methylphenazine hydrochloride (Neutral Red) (Sigma Aldrich, 90%) was used as an anode active material. 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride (Neutral Red) was weighed in an amount corresponding to 0.05M and placed in a 10 ml volumetric flask, and the supporting electrolyte was added to the 100 ml mark to prepare a cathode electrolyte.

3. Electrode pretreatment

Carbon felt (NIPPON CARBON) used as an electrode was activated at 400° C. for 2 hours.

4. Cell assembly

A battery cell was produced as follows.

As shown in FIGS. 2 to 11, the outer case, carbon felt (anode), gasket, membrane, gasket, carbon felt (cathode), and outer case were stacked and assembled in this order. In order to increase the surface area of the electrode, two sheets of carbon felt were stacked and used as an anode and a cathode, respectively. And in order to reduce the risk of leakage and the internal resistance of the battery cell, it was assembled by applying strong pressure to the outside of the battery cell using bolts and nuts. After that, a positive electrode electrolyte and a negative electrode electrolyte were respectively added to carbon felt separated into a positive electrode and a negative electrode based on a membrane, and carbon felt was wetted. That is, carbon felt (anode) was wetted with a positive electrode electrolyte, and carbon felt (cathode) was wetted with a negative electrode electrolyte. The volumes of the positive electrolyte and negative electrolyte were used in 2 ml each.

A battery cell of the shape shown in FIGS. 2 to 4 was fabricated using carbon felt as a positive electrode and a negative electrode, and Nafion as an anion exchange membrane as a separator. 2 to 4 are photographs of a battery cell. 5 is a cross-sectional view illustrating a method of assembling a battery cell. 6 is a front view showing the outer case of the battery cell, FIG. 7 is a side view showing the outer case of the battery cell, and FIG. 8 is a plan view showing the outer case of the battery cell. 9 is a front view showing the cover of the battery cell, FIG. 10 is a side view showing the cover of the battery cell, and FIG. 11 is a plan view showing the cover of the battery cell.

Fabrication of the battery cell was carried out as follows. As shown in FIG. 5, a carbon felt 220a used as an anode is inserted into the concave portion 212a provided in the outer case 210a, and made of silicon to suppress leakage of the electrolyte to the outside. A gasket (230a) is attached so that the concave portion (212a) can be sealed, and a separator 240 is installed adjacent to the gasket (230a), and the concave portion (112b) provided in the outer case (210b) The carbon felt (220b) used as the cathode is inserted, and a gasket (230b) made of silicon is attached so that the concave portion (212b) can be sealed to prevent leakage of the electrolyte to the outside. After making contact with 240, a battery cell was manufactured by pressing between the outer case 210a and the outer case 210b using a bolt.

6 to 8, the outer case 210 is provided with a concave portion 212 as a space capable of accommodating carbon felt used as an anode and a cathode. In addition, the outer case 210 is provided with a through hole 214 into which a bolt is inserted. In addition, the outer case 210 is provided with an opening 216 for injecting an electrolyte or inserting the cover 250.

As shown in FIGS. 9 to 11, the cover 250 is provided with a through hole 252 for inserting a conductive wire connecting an anode or a cathode with a power supply.

5. Analysis method

In order to observe the electrochemical behavior of the assembled battery cell, a two-electrode charging/discharging test was conducted. Charge and discharge tests were conducted using a cell test system (Wonatech, Co. Ltd). The current density of charging and discharging was set to 4.02 mA, and charging and discharging were performed with a constant current (CC). To increase the output, the output current was increased from 1C to C4, and the output current was lowered to 1C to compare the output capacity by current.

12 is a graph showing a measurement result of a charge/discharge curve using an active material.

Referring to FIG. 12, as a result of charging and discharging in the battery, it was confirmed that a discharge value of approximately 0.85 V was provided.

As the active material used, Mn(phen) ₃ SO ₄ was used in a concentration of 0.1M, and 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride (Neutral Red) was used in a concentration of 0.05M, and the concentration of usable active material was about 0.01 to 5.0 M. It is believed that a derivative active material similar to the above structure can be used at the same concentration.

In the above, a preferred embodiment of the present invention has been described in detail, but the present invention is not limited to the above embodiment, and various modifications are possible by those of ordinary skill in the art.

110: anode
115: anode cell
120: cathode
125: cathode cell
130: separator
140: anode electrolyte
150: cathode electrolyte
155: first tank
170: second tank
160, 165, 175, 180: conduit

Claims (12)

In a flow battery in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode, a negative electrode, and a separator disposed between the positive electrode current collector and the negative electrode current collector to perform charging and discharging,
The cathode electrolytic solution Mn in the positive electrode active material (phen) ₃ X _n (where, "phen" is the "1,10-phenanthroline", n is a natural number of 1 or 2, X is SO ₄ ^2-, NO ₃ ^{-, Cl -, Br - I -,} BF 4 - and PF ₆ ^- flow cell comprising the one or more anionic species) selected from.
The method of claim 1, wherein the positive electrode electrolyte further comprises a supporting electrolyte,
The supporting electrolyte is an electrolyte containing cations and anions,
The cation of the supporting electrolyte includes at least one cation selected from quaternary ammonium ions, high molecular ammonium ions, lithium ions, sodium ions, hydrogen ions and potassium ions,
The anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F -, I 2 Br -, Br 2 I -, NO 3 - ^{_{, SO 4 2-, PF 6 -}} , ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, (CF 3 SO 2) 2 N -, (C 2 F 5 ^{_{SO 2) 2 N -, (}} CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- stream comprises at least one anion selected from the group consisting of battery.
The flow battery according to claim 2, wherein the supporting electrolyte has a concentration of 0.05 to 5M.
The flow battery according to claim 1, wherein the negative electrode electrolyte contains 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride as a negative electrode active material.
The method of claim 4, wherein the positive electrode active material has a concentration of 0.01 to 5.0 M,
Flow battery, characterized in that the negative active material has a concentration of 0.01 to 5.0 M.
The method of claim 4, wherein the cathode electrolyte further comprises a supporting electrolyte,
The supporting electrolyte is an electrolyte containing cations and anions,
The cation of the supporting electrolyte includes at least one cation selected from quaternary ammonium ions, high molecular ammonium ions, lithium ions, sodium ions, hydrogen ions and potassium ions,
The anion of the supporting electrolyte is ^{Cl -, Br -, I -} , F -, I 3 -, I 2 F -, Br 2 F -, Cl 2 F -, I 2 Br -, Br 2 I -, NO 3 - ^{_{, SO 4 2-, PF 6 -}} , ClO 4 -, BF 4 -, SbF 6 -, CF 3 SO 3 -, (CN) 2 N -, (CF 3 SO 2) 2 N -, (C 2 F 5 ^{_{SO 2) 2 N -, (}} CF 3 SO 2) 3 C -, CF 3 CO 2 -, C 3 F 7 CO 2 - and CH ₃ CO ₂ ^- stream comprises at least one anion selected from the group consisting of battery.
The flow battery according to claim 6, wherein the supporting electrolyte has a concentration of 0.05 to 5M.
The flow battery according to claim 1, wherein the positive electrolyte and the negative electrolyte contain an aqueous solvent that dissociates the electrolyte.
The flow battery according to claim 1, wherein the positive electrode and the negative electrode contain carbon felt having electrical conductivity.
The flow battery according to claim 9, wherein the carbon felt is an activated felt at 300 to 550°C.
The flow battery according to claim 1, wherein the positive electrode active material has a higher redox potential than that of the negative electrode active material.
The flow battery according to claim 1, wherein the positive electrode active material contains a derivative represented by the following structural formula.
[constitutional formula]

Wherein G includes at least one functional group selected from the group consisting of nitro, cyan, methyl, ethyl, propyl, isopropyl and butyl,
X is SO ₄ ^2-, NO ₃ ^- comprises at least one anion selected from the group consisting of ^{-, Cl -, Br - I} -, BF 4 - and PF _6.

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