KR20100116888A - Preparation method of separator for all-vanadium redox flow secondary battery and separator thereof - Google Patents

Abstract

PURPOSE: A manufacturing method of a separator and the separator are provided to prevent the degradation of the voltage efficiency by securing the excellent oxidation resistance and the low film resistance. CONSTITUTION: A manufacturing method of a separator for an all-vanadium redox flow secondary battery comprises the following steps: dissolving a copolymer polymer block-copolymerizied with polysulfone and polyphenylene sulfide sulfone, with 1,1,2,2-tetrachloroethane; adding an ion exchange radical introduction solvent; applying a positive ion exchanger to the copolymer polymer by the sulfonation; washing the sulfonated hydrocarbon polymer with methanol, and compress-drying; dissolving the sulfonated hydrocarbon polymer to N-methylpyrrolidone; and casting the dissolved solution to a glass plate, and drying.

Description

Manufacture method of separator for vanadium redox-flow secondary battery and its separator {Preparation method of separator for all-vanadium redox flow secondary battery and separator}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a diaphragm for vanadium redox-flow secondary batteries, and a diaphragm for the same. In order to replace the perfluorinated membrane, which increases the voltage resistance and decreases the voltage efficiency, the present invention relates to the manufacture of a diaphragm using a hydrocarbon-based polymer, and is an inexpensive, electrochemical and mechanical stability for a vanadium redox-flow secondary battery. The present invention relates to a method for producing a diaphragm using a hydrocarbon-based polymer having high resistance, oxidation resistance, and heat resistance, and a diaphragm thereof.

Redox-flow secondary batteries have been researched for high-capacity power storage technology or emergency power for smooth operation of power generation systems that use intermittent natural energy such as solar power generation and wind power generation [Ref. 1].

In particular, the vanadium redox-flow secondary battery using a vanadium solution as an electrolyte solves problems such as hydrogen gas generation and a decrease in battery capacity, which are a problem in the redox-flow battery using Fe / Cr as an electrolyte. The electromotive force and energy density are high (1.4V, energy density 30-50Wh / kg), the system can be simplified, and the operability is expected to be improved [Ref. 2].

Vanadium redox-flow secondary batteries include tetravalent vanadium ions in the positive electrode upon charging to be (VO ²⁺⁾ is 5 (VO ₂ ^+), the negative electrode 3 is a vanadium ion (V ³⁺⁾ 2 is (V ²⁺ ), And at the time of discharge, the valence of vanadium ions is reversed, and the charge and discharge reaction proceeds.

However, the biggest problem with vanadium redox-flow secondary batteries lies in the diaphragm. The styrene-divinyl benzen diaphragm used in the Fe / Cr system is oxidatively deteriorated by a pentavalent vanadium solution, which is also used as an oxidizing agent. • There is a problem that the voltage efficiency of the battery decreases with the increase of the membrane resistance during discharge operation [Ref. 3].

In order to maintain high current efficiency, the vanadium redox-flow secondary battery diaphragm should minimize self-discharge caused by penetration of the active species of vanadium ions and have a low film resistance in order to minimize voltage degradation. In addition, it must have high acid resistance even during long operation.

Therefore, development of a low cost, high electrochemical and mechanically stable diaphragm for vanadium redox-flow secondary batteries is required.

[references]

1) Research Trends on Hwang Gap-jin, Kang An-su, Kang Dae-soo, Redox-flow Secondary Battery, Chemical Industry and Technology, 16 (5), p.455 (1998).

2) Gab-Jin Hwang and H. Ohya, "Preparation of cation exchange membrane as a separator for the all-vanadium redox flow battery", J. Membrane Sci., 120, p.55 (1996).

3) Gab-Jin Hwang and H. Ohya, "Crosslinking of anion exchange membrane by accelerated electron radiation as a separator for the all-vanadium redox flow battery", J. Membrane Sci., 132, p.55 (1997).

4) Gab-Jin Hwang and H. Ohya, "Preparation of anion exchange membrane based on block copolymers Part I. Amination of the chloromethylated copolymers", J. Membrane Sci., 140, p. 195 (1998).

An object of the present invention for solving the above problems is to manufacture a diaphragm using a hydrocarbon polymer having low cost, high electrochemical and mechanical stability, ie low membrane resistance, oxidation resistance, and heat resistance, for a vanadium redox-flow secondary battery. A method and a diaphragm prepared therefrom are provided.

The present invention, which achieves the object as described above and removes the drawbacks of the related art, has been described in the present invention. In the manufacturing method of the diaphragm using a hydrocarbon type polymer which replaces the perfluorine type film which raises this and decreases a voltage efficiency,

After dissolving the copolymerized copolymer of polysulfone and polyphenylene sulfide sulfone, which are engineering plastics, in tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane), an ion exchanger introducing solvent is added and nitrogen gas Sulfonation reaction was carried out while introducing a cation exchanger into the copolymerized polymer. The sulfonated polymer was washed with methanol, gelled and deposited sulfonated hydrocarbon polymer was dried under reduced pressure, and the dried sulfonated hydrocarbon polymer was methylpyridine. After dissolving in redon (NMP), the dissolved solution is cast on a glass plate and dried to prepare a hydrocarbon membrane (cation exchange membrane) in the form of a film having the following chemical molecular formula for a vanadium redox-flow secondary battery. It is achieved by providing a method for producing the diaphragm.

[Chemical molecular formula]

M: n = 1: 1 in the above.

The ion exchanger introduction solvent is characterized in that it is used one selected from chlorosulfonic acid (CSA, chlorosulfonic acid), sulfuric acid (sulfuric acid), sulfur trioxide (SO ₃ ).

The ion exchanger introducing solvent is characterized in that it is added at a rate of 1ml / min while stirring 1 ~ 10ml.

The nitrogen gas is characterized in that the sulfonation reaction for 30 minutes to 3 hours at room temperature (25 ℃) ~ 160 ℃ while flowing at a rate of 30 ~ 300ml / min.

The gelated and deposited sulfonated hydrocarbon polymer is characterized by drying under reduced pressure for 1 to 20 hours at 50 ℃ ~ 140 ℃.

After dissolving the dried sulfonated hydrocarbon polymer in methylpyrilidone (NMP) so that the ratio is 1 g: 1.5-2 ml, casting the dissolved solution on a glass plate and drying at 50-140 ° C. for 2 hours or more. It is done.

In another embodiment, the present invention is a hydrocarbon membrane (cation exchange membrane) in the form of a film prepared by the above method having the following chemical molecular formula, wherein the membrane resistance per molar sulfuric acid solution reference is 1.0 Ω · cm ² or less, and vanadium re It is achieved by providing a vanadium redox-flow secondary battery diaphragm characterized in that the electromotive force at 100% state of charge when used as a diaphragm for a dox-flow secondary battery is 1.4V.

[Chemical molecular formula]

M: n = 1: 1

In another embodiment, the present invention replaces a perfluorinated membrane which increases the voltage resistance of the vanadium redox-flow secondary battery, which is one of the high-capacity power storage methods, and increases the voltage resistance during operation of the high-cost and charge-discharge batteries. In the method for producing a diaphragm using a hydrocarbon-based polymer,

After dissolving the copolymer copolymer of polysulfone and polyphenylene sulfide sulfone, which is an engineering plastic series, in tetrachloroethane (TCE, 1, 1, 2, 2-tetrachloroethane), heteropoly acid is dissolved in dimethylacetamide ( A solution dissolved in DMAc, NN-dimethylacetamide) is added, and an ion exchanger introduction solvent is added thereto, and a sulfonation reaction is carried out while flowing nitrogen gas to introduce a cation exchanger and an inorganic supplement to the copolymer polymer, and a sulfonated reaction oil- After washing the inorganic composite hydrocarbon polymer with methanol, taking the gelled and deposited sulfonated organic-inorganic composite hydrocarbon polymer and drying under reduced pressure, the dried sulfonated organic-inorganic composite hydrocarbon polymer was dissolved in methylpyrilidone (NMP), Organic-inorganic composite carbon in film form having the following chemical molecular formula by casting the dissolved solution on a glass plate and drying it It is achieved by providing a method for producing a vanadium redox-flow secondary battery diaphragm characterized by producing a hydrogen sulfide diaphragm (cation exchange membrane).

[Chemical molecular formula]

M: n = 1: 1 in the above.

The ion exchanger introducing solvent is characterized in that it uses one selected from chlorosulfonic acid (CSA, chlorosulfonic acid), sulfuric acid (sulfuric acid), sulfur trioxide (SO ₃ ).

The ion exchanger introducing solvent is characterized in that it is added at a rate of 1ml / min while stirring 1 ~ 10ml.

The heteropoly acid (heteropoly acid) is characterized in using one selected from tungstophosphoric acid (TPA, tungstophosphoric acid), phospho molybdate, silico molybdate.

The heteropoly acid (heteropoly acid) is dissolved in a dimethylacetamide (DMAc, N-N-dimethylacetamide) so that the ratio is 1g: 1ml, characterized in that the addition of 0.1 to 10g.

The nitrogen gas is characterized in that the sulfonation reaction for 30 minutes to 3 hours at room temperature (25 ℃) ~ 160 ℃ while flowing at a rate of 30 ~ 300ml / min.

The gelated and deposited sulfonated organic-inorganic composite hydrocarbon polymer is characterized by drying under reduced pressure for 1 to 20 hours at 50 ℃ ~ 140 ℃.

After dissolving the dried sulfonated organic-inorganic hybrid hydrocarbon polymer to methylpyrilidone (NMP) in a ratio of 1 g: 1.5 to 2 ml, the dissolved solution was cast on a glass plate and then at 50 to 140 ° C. for at least 2 hours. It is characterized by drying.

In another embodiment, the present invention is a hydrocarbon membrane (cation exchange membrane) in the form of a film prepared by the above method having the following chemical molecular formula, wherein the membrane resistance per molar sulfuric acid solution reference is 1.0 Ω · cm ² or less, and vanadium re It is achieved by providing a vanadium redox-flow secondary battery diaphragm characterized in that the electromotive force at 100% state of charge when used as a diaphragm for a dox-flow secondary battery is 1.4V.

[Chemical molecular formula]

M: n = 1: 1

The hydrocarbon-based diaphragm according to the present invention has excellent thermal stability, and can be a diaphragm having excellent oxidation resistance even under a pentavalent vanadium ion solution used as an electrolyte solution for vanadium redox-flow secondary batteries, compared to a perfluorine-based membrane. When used as a redox-flow secondary battery diaphragm, it is a useful invention that can achieve the effect of preventing voltage degradation by improving the voltage efficiency and high oxidation resistance together with low film resistance without significantly reducing the electromotive force. It is an invention that is expected to be greatly used in the industry.

Hereinafter, the configuration and the operation of the embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The present invention relates to the fabrication of a diaphragm using a hydrocarbon-based polymer for use as a vanadium redox-flow secondary battery, one of a large-capacity power storage method, polysulfone (Psf, which is an engineering plastics system with high mechanical strength and heat resistance). After preparing a copolymer copolymerized with polyphenylene sulfide sulfone (PPSS, polyphenylenesulfidesulfone) in polysulfone, an ion exchanger is introduced into the copolymer to inexpensive, low film resistance, and heat resistant, thereby providing vanadium redox- The manufacturing method of the diaphragm which can be used for a flow secondary battery is related.

In more detail, commercially available polysulfone is dissolved in an organic solvent, methylpyrilidone (NMP, N-methylpyrilidone), followed by dichlorodiphenylsulfone (DCDPS, 4,4'-dichloro diphenyl sulfone) and sodium sulfide hydrate ( Sodium sulfide hydrate) and a catalyst, lithium acetate dihydrate, were added and polymerized for 4 hours while flowing nitrogen gas at 160 ° C. while stirring, and at 4 hours, chloromethylpropane (3-chloro- By stopping the reaction by slowly adding 2-methyl-1-propane, a polysulfone (Psf, polysulfone) having the following chemical molecular formula is block copolymer of polyphenylene sulfidesulfone (PPSS, polyphenylenesulfidesulfone) (Psf-PPSS) ) Is prepared [Ref. 4].

The reason why the reaction terminator is used is so that the mixing ratio of polysulfone and polyphenylene sulfide sulfone is about 1: 1.

The reason for limiting the mixing ratio is that since the ratio of polysulfone is high, it is difficult to use in aqueous sulfuric acid solution even if a diaphragm is prepared because polysulfone is weak to water.

The prepared copolymer (Psf-PPSS) is washed several times with lukewarm water to remove sodium chloride (NaCl) generated during the reaction, and then washed several times with methanol (methanol) to remove the unreacted substances.

Thus washed copolymerized polymer (Psf-PPSS) is dried under reduced pressure at 140 ℃. Instead of drying under reduced pressure, drying may be performed in the air for at least 24 hours or at 140 ° C or lower using an oven.

After dissolving the dried copolymer polymer (Psf-PPSS) in tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane), while stirring the chlorosulfonic acid (CSA, chlorosulfonic acid), the solvent for introducing the ion exchange group The addition and addition of a cation exchanger into the copolymer by sulfonation at room temperature (25 ° C.) to 160 ° C. for 30 minutes to 3 hours while flowing nitrogen gas. This is because if the temperature is lower than the lower limit, the reaction does not occur well, and if it exceeds 160 ° C, the volatilization of the ion exchanger introducing solvent is faster than the rate at which the ion exchanger is introduced into the membrane. The reason for limiting the time is that the reaction is less likely to occur when the value is smaller than the lower limit value, and when the reaction is performed for 3 hours or more, aggregation occurs and becomes harder than the gelled portion necessary for producing the film.

Chlorosulfonic acid (CSA, chlorosulfonic acid), which is an ion exchanger introducing agent, is added at a rate of 1 ml / min while stirring 1-10 ml. At this time, if the ion exchanger solvent is used smaller than the lower limit, the reaction does not occur well, and if it is used a lot, it is true that many ion exchangers are introduced. Beyond, the film resistance value in 1 mole sulfuric acid solution increases. Therefore, it is important to find the ratio of the copolymerization polymer and the ion exchange solvent which shows a low membrane resistance when preparing the diaphragm. In the present invention, the amount of the introduction agent of the ion exchange group is limited as described above.

In addition, the reason for limiting the addition time is that the reaction is less likely to occur when it is used below the lower limit value, and when the addition rate is high, the amount of ion exchange groups introduced into the copolymer is reduced.

In addition, the reason for flowing nitrogen gas is to prevent side reactions, nitrogen gas flows at a rate of 30 ~ 300ml / min. If the rate of nitrogen gas is less than the lower limit, the reaction does not occur well. If the flow rate is high, all of the gas is released to the atmosphere before the reaction of CSA, an ion exchange solvent. This is because CSA, an ion exchange solvent, has a very high volatilization rate.

In addition, sulfuric acid, sulfur trioxide (SO3), or the like may be used as an ion exchanger introduction solvent.

The sulfonated polymer is washed with methanol, gelled and precipitated sulfonated hydrocarbon polymer, and dried under reduced pressure at 50 ° C to 140 ° C for 1 to 20 hours. At this time, if the temperature is less than the lower limit, the reaction does not occur well, and when drying at a temperature of 140 ° C. or more for a long time, the sulfonated hydrocarbon polymer gradually burns out. In addition, the reason for carrying out the drying under reduced pressure was to remove impurities such as methanol, which is used as a cleaning agent more effectively, and showed the best effect in the interval value.

The dried sulfonated hydrocarbon polymer is dissolved in methylpyrilidone (NMP), cast the dissolved solution on a glass plate, and dried at 50-140 ° C. for at least 2 hours to form a film-type cation exchange membrane having a chemical molecular formula as follows. Is produced. At this time, if the temperature is smaller than the lower limit, the reaction does not occur well, and if the film is dried at 140 ° C. or higher, the film is not formed but the film adheres to the glass plate. The reason for limiting the drying time is due to the viscosity of the solution dissolved in NMP. If the viscosity is large, it is dried in a long time, and if the viscosity is low, it is dried in a short time, and has the most suitable viscosity for the present invention in the above section.

In addition, the sulfonated hydrocarbon polymer dried during the dissolution is dissolved in methylpyrilidone (NMP) so that the ratio is 1g: 1.5 ~ 2ml. The reason for the ratio limitation is that the film is not well formed if the ratio of the dried sulfonated hydrocarbon polymer and NMP is higher or lower than this.

M: n = 1: 1 in the above. The reason for this assumption is that if the ratio of polysulfone (m) is high, polysulfone is weak in water, and thus it is difficult to use the aqueous solution of sulfuric acid even if a diaphragm is produced.

At this time, the ratio of the sulfonated hydrocarbon polymer and the solvent NMP is 1g: 1.5-2ml. The reason for limiting the amount of the solvent is to suppress the phenomenon of slack and dispersion of the solution when casting to produce a film.

As the casting plate for making the film, a silicone rubber plate or a screen printing machine may be used.

In another embodiment, the present invention is dissolved in a dry copolymer (Psf-PPSS) in tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane) and then tungstophosphoric which is one of heteropoly acid (heteropoly acid) A solution of acid (TPA, tungstophosphoric acid) dissolved in dimethylacetamide (DMAc, NN-dimethylacetamide) is added, and chlorosulfonic acid (CSA, chlorosulfonic acid), which is an ion exchanger introduction solvent, is added thereto under stirring, and nitrogen gas is added to 30 The cation exchanger and the inorganic supplement are introduced into the copolymer by sulfonation at room temperature (25 ° C.) to 160 ° C. for 30 minutes to 3 hours while flowing at a rate of ˜300 ml / min.

The ratio of tungstophosphoric acid (TPA, tungstophosphoric acid) and dimethylacetamide (DMAc, NN-dimethylacetamide) is 1 g: 1 ml, and 0.1 to 10 g of the dissolved solution is added thereto. Add 1-10 ml of sulfonic acid (CSA, chlorosulfonic acid) at a rate of 1 ml / min while stirring. The reason why the amount of TPA dissolved in DMAc is limited is that if the amount is less than the lower limit, the reaction does not occur well, and if it is more than that, the ion exchanger is difficult to be introduced, thereby increasing the membrane resistance in the 1 mol sulfuric acid solution.

In addition to TPA, other types of heteropolyacids, phospho molybdate and silico molybdate may be added.

The sulfonated polymer is washed with methanol, gelled and precipitated sulfonated hydrocarbon polymer, and dried under reduced pressure at 50 ° C to 140 ° C for 1 to 20 hours.

The dried sulfonated organic-inorganic hybrid hydrocarbon polymer is dissolved in methylpyrilidone (NMP), cast the dissolved solution on a glass plate, and dried at 50-140 ° C. for at least 2 hours to form an organic-inorganic hybrid cation exchange membrane in a film form. This is produced.

Hereinafter, the configuration and the operation of the embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a surface and cross-sectional photograph of the hydrocarbon-based diaphragm developed in the present invention, the thickness of the produced hydrocarbon-based diaphragm is 50 ~ 170μm.

Usually, the thickness of the perfluorinated film is 185 µm, and the film resistance in the 1 mol sulfuric acid solution also changes depending on the thickness of the film. That is, as the thickness increases, the membrane resistance also increases. The hydrocarbon-based membrane produced in the present invention has a smaller thickness than the conventional membrane and has a low membrane resistance of 1.0 Ω · cm ² in a 1 mol sulfuric acid solution.

Figure 2 is a graph showing the thermal stability by TGA (Thermogravimetric Analyzer) analysis of the hydrocarbon-based diaphragm developed in the present invention, it can be seen that it is thermally stable compared to the typical perfluorine-based diaphragm Nafion117.

3 is a graph showing the change in membrane resistance in a 1 mole sulfuric acid solution according to the amount of the ion exchanger introduced solvent of the hydrocarbon-based diaphragm developed in the present invention, the membrane resistance is 4kΩ · cm ² when the initial ion exchanger is not introduced However, the resistance tended to decrease with the introduction of the ion exchanger, and when 3 ml of CSA was introduced, the lowest resistance value was 0.96 Ω · cm ² . Therefore, the manufactured diaphragm can be used as a vanadium redox-flow secondary battery diaphragm.

4 is a graph showing the change in membrane resistance in 1 mol sulfuric acid solution according to the change of TPA amount in the amount of 4 ml CSA of the organic-inorganic hybrid hydrocarbon-based diaphragm developed in the present invention, the membrane when the initial ion exchanger is not introduced The resistance was 4 kΩ · cm ² , but the resistance tended to decrease with the increase of the amount of TPA, and the smallest value was 0.94 Ω · cm ² at 0.5 g of TPA. Had. Therefore, the manufactured diaphragm can be used as a vanadium redox-flow secondary battery diaphragm.

5 is a graph showing charge and discharge characteristics according to the state of charge when the hydrocarbon-based diaphragm developed in the present invention is applied to a vanadium redox-flow secondary battery, and the electromotive force of the cell increases as the state of charge increases. It had a value of 1.4V at a state of charge of%. Therefore, the produced hydrocarbon-based diaphragm does not significantly reduce the electromotive force, so it can be used as a vanadium redox-flow secondary battery diaphragm.

6 is a graph showing the charge and discharge characteristics according to the state of charge when the organic-inorganic hybrid hydrocarbon-based diaphragm developed in the present invention is applied to a vanadium redox-flow secondary battery. The higher the value, the 1.4V at 100% state of charge. Therefore, the produced hydrocarbon-based diaphragm does not significantly reduce the electromotive force, so it can be used as a vanadium redox-flow secondary battery diaphragm.

Hereinafter is a preferred embodiment of the present invention.

[Example 1]

25 g of commercially available polysulfone was dissolved in 120 ml of an organic solvent, methyl pyrilidone (NMP), followed by 19 g of dichlorodiphenylsulfone (DCDPS, 4,4'-dichloro diphenyl sulfone) and sodium sulfide hydrate (sodium). 5 g of sulfide hydrate and 6 g of lithium acetate dihydrate were added to the mixture, and the mixture was stirred for 4 hours while flowing nitrogen gas at a flow rate of 100 ml / min at 160 ° C. while stirring. Slowly add 20 ml of methyl propane (3-chloro-2-methyl-1-propane) to stop the reaction, and block copolymer of polyphenylene sulfide sulfone (PPSS) to polysulfone (Psf, polysulfone) (Psf -PPSS).

The prepared copolymer (Psf-PPSS) was washed several times with lukewarm water to remove sodium chloride (NaCl) generated during the reaction, and then washed several times with methanol (methanol) to remove unreacted substances.

The washed copolymer (Psf-PPSS) was dried under reduced pressure at 140 ° C. for 6 hours.

7 g of dried copolymer polymer (Psf-PPSS) was dissolved in 50 ml of tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane), and then 1 to chlorosulfonic acid (CSA, chlorosulfonic acid), which is an ion exchanger introduction solvent. 10 ml was added at a rate of 1 ml / min while stirring and sulfonated at room temperature (25 ° C.) for 1 hour while flowing at a rate of 100 ml / min of nitrogen gas to introduce a cation exchanger into the copolymer.

The sulfonated polymer was washed with methanol, gelled and precipitated sulfonated hydrocarbon polymer, and dried under reduced pressure at 90 ° C for 5 hours.

The dried sulfonated hydrocarbon polymer was dissolved in methylpyrilidone (NMP), and then the dissolved solution was cast on a glass plate and dried at 70 ° C. for 2 hours or more to prepare a hydrocarbon-based cation exchange membrane in the form of a film.

The thermal stability by TGA, membrane resistance in 1 mol sulfuric acid solution, and the cell voltage according to the state of charge and current density when used as the membrane for vanadium redox-flow secondary battery were measured. The prepared diaphragm showed higher thermal stability compared to Nafion117, a typical perfluorine-based membrane, and the membrane resistance in 1 mole sulfuric acid solution showed a value of 1.0 Ω · cm ² or more at a 3 ml CSA content, and vanadium redox-flow. When used as a secondary battery diaphragm, the electromotive force at 100% state of charge was 1.4V (see FIGS. 2, 3, and 5).

[Example 2]

7 g of dried copolymer polymer (Psf-PPSS) was dissolved in 50 ml of tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane), and then tungstophosphoric acid (TPA) was added to dimethylacetamide (DMAc, NN-dimethylacetamide) was added 0.1 ~ 2g, and 4ml of chlorosulfonic acid (CSA, chlorosulfonic acid), an ion exchanger introduction solvent, was added at a rate of 1ml / min while stirring and at a rate of 100ml / min of nitrogen gas. Sulfonation was performed at room temperature (25 ° C.) for 1 hour while flowing to introduce a cation exchanger and an inorganic supplement into the copolymer.

The sulfonated polymer was washed with methanol, gelled and precipitated sulfonated hydrocarbon polymer, and dried under reduced pressure at 90 ° C for 5 hours.

The dried sulfonated organic-inorganic hybrid hydrocarbon polymer was dissolved in methylpyrilidone (NMP), cast the dissolved solution on a glass plate, and dried at 70 ° C. for at least 2 hours to prepare an organic-inorganic hybrid cation exchange membrane in the form of a film. It was.

Thermal stability by TGA, membrane resistance in 1 mole sulfuric acid solution, and cell voltage according to the state of charge and current density when used as membrane for vanadium redox-flow secondary battery Measured. The fabricated organic-inorganic hybrid hydrocarbon-based diaphragm showed higher thermal stability compared to Nafion117, a typical perfluorine-based membrane, and the membrane resistance of 1 mole sulfuric acid solution was 1.0Ω · cm ² or less at 0.5g TPA or higher. When used as a diaphragm for vanadium redox-flow secondary battery, the electromotive force at 100% state of charge showed 1.4V (see FIGS. 2, 4, and 6).

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

1 is a surface and a cross-sectional photograph of a hydrocarbon-based diaphragm developed in the present invention,

2 is a graph showing the thermal stability of the hydrocarbon-based diaphragm developed in the present invention,

3 is a graph showing a change in membrane resistance in a 1 mole sulfuric acid solution according to the amount of the ion exchange group introduced solvent of the hydrocarbon-based diaphragm developed in the present invention,

4 is a graph showing the change of membrane resistance in 1 mol sulfuric acid solution according to the change of TPA amount in the amount of CSA of 4ml of the organic-inorganic hybrid hydrocarbon-based diaphragm developed in the present invention,

5 is a graph showing charge and discharge characteristics according to the state of charge when the hydrocarbon-based diaphragm developed in the present invention is applied to a vanadium redox-flow secondary battery.

6 is a graph showing charge and discharge characteristics according to the state of charge when the organic-inorganic hybrid hydrocarbon-based diaphragm developed in the present invention is applied to a vanadium redox-flow secondary battery.

Claims (16)

Diaphragm using hydrocarbon-based polymers, which replaces perfluorine-based membranes that reduce voltage efficiency by increasing membrane resistance during operation of expensive and charged / discharged batteries used in vanadium redox-flow secondary batteries, one of the large-capacity power storage methods. In the manufacturing method of After dissolving the copolymerized copolymer of polysulfone and polyphenylene sulfide sulfone, which are engineering plastics, in tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane), an ion exchanger introducing solvent is added and nitrogen gas Sulfonation reaction was carried out while introducing a cation exchanger into the copolymerized polymer. The sulfonated polymer was washed with methanol, gelled and deposited sulfonated hydrocarbon polymer was dried under reduced pressure, and the dried sulfonated hydrocarbon polymer was methylpyridine. After dissolving in redon (NMP), the dissolved solution is cast on a glass plate and dried to prepare a hydrocarbon membrane (cation exchange membrane) in the form of a film having the following chemical molecular formula for a vanadium redox-flow secondary battery. Method of manufacturing the diaphragm. [Chemical molecular formula]

M: n = 1: 1 The method according to claim 1, Preparation of the vanadium redox-flow secondary battery diaphragm characterized in that the ion exchanger introduction solvent is selected from chlorosulfonic acid (CSA, chlorosulfonic acid), sulfuric acid (sulfuric acid), sulfur trioxide (SO ₃ ). Way. The method according to claim 1, The ion exchanger introducing solvent is a method for producing a vanadium redox-flow secondary battery diaphragm, characterized in that the addition of 1 to 10ml at a rate of 1ml / min while stirring. The method according to claim 1, Wherein the nitrogen gas flowing at a rate of 30 ~ 300ml / min at room temperature (25 ℃) ~ 160 ℃ sulfonation reaction for 30 minutes to 3 hours, characterized in that the manufacturing method of the vanadium redox-flow secondary battery diaphragm. The method according to claim 1, The gelated and deposited sulfonated hydrocarbon polymer is dried under reduced pressure at 50 ° C. to 140 ° C. for 1 to 20 hours. The method according to claim 1, After dissolving the dried sulfonated hydrocarbon polymer in methylpyrilidone (NMP) so that the ratio is 1 g: 1.5-2 ml, casting the dissolved solution on a glass plate and drying at 50-140 ° C. for 2 hours or more. The manufacturing method of the diaphragm for vanadium redox flow secondary batteries which are used. Claims 1 to 6 and is prepared by the method of the hydrocarbon to the diaphragm of the film type having the chemical molecular formula (cation exchange membrane) according to any hanhang, based on 1 mol of sulfuric acid per film resistance indicates a value of 1.0Ω · cm ² or less, vanadium les A vanadium redox-flow secondary battery diaphragm characterized by having an electromotive force of 1.4 V at 100% state of charge when used as a diaphragm for a dox-flow secondary battery. [Chemical molecular formula]

M: n = 1: 1 Diaphragm using hydrocarbon-based polymers, which replaces perfluorine-based membranes that reduce voltage efficiency by increasing membrane resistance during operation of expensive and charged / discharged batteries used in vanadium redox-flow secondary batteries, one of the large-capacity power storage methods. In the manufacturing method of After dissolving the copolymer copolymer of polysulfone and polyphenylene sulfide sulfone, which is an engineering plastic series, in tetrachloroethane (TCE, 1, 1, 2, 2-tetrachloroethane), heteropoly acid is dissolved in dimethylacetamide ( A solution dissolved in DMAc, NN-dimethylacetamide) is added, and an ion exchanger introduction solvent is added thereto, and a sulfonation reaction is carried out while flowing nitrogen gas to introduce a cation exchanger and an inorganic supplement to the copolymer polymer, and a sulfonated reaction oil- After washing the inorganic composite hydrocarbon polymer with methanol, taking the gelled and deposited sulfonated organic-inorganic composite hydrocarbon polymer and drying under reduced pressure, the dried sulfonated organic-inorganic composite hydrocarbon polymer was dissolved in methylpyrilidone (NMP), Organic-inorganic composite carbon in film form having the following chemical molecular formula by casting the dissolved solution on a glass plate and drying it A method for producing a vanadium redox-flow secondary battery diaphragm characterized by producing a hydrogen sulfide diaphragm (cation exchange membrane). [Chemical molecular formula]

M: n = 1: 1 The method according to claim 8, Preparation of the vanadium redox-flow secondary battery diaphragm characterized in that the ion exchanger introduction solvent is selected from chlorosulfonic acid (CSA, chlorosulfonic acid), sulfuric acid (sulfuric acid), sulfur trioxide (SO ₃ ). Way. The method according to claim 9, The ion exchanger introducing solvent is a method for producing a vanadium redox-flow secondary battery diaphragm, characterized in that the addition of 1 to 10ml at a rate of 1ml / min while stirring. The method according to claim 8, The heteropoly acid (heteropoly acid) is a method for producing a diaphragm for vanadium redox-flow secondary battery, characterized in that using one selected from tungstophosphoric acid (TPA, tungstophosphoric acid), phospho molybdate, silico molybdate. The method according to claim 8, Method for producing a diaphragm for vanadium redox-flow secondary battery, characterized in that 0.1 to 10 g of the dissolved heteropoly acid (DMAc, NN-dimethylacetamide) is dissolved in a ratio of 1 g: 1 ml to 1 ml. . The method according to claim 8, Wherein the nitrogen gas flowing at a rate of 30 ~ 300ml / min at room temperature (25 ℃) ~ 160 ℃ sulfonation reaction for 30 minutes to 3 hours, characterized in that the manufacturing method of the vanadium redox-flow secondary battery diaphragm. The method according to claim 8, The gelated and deposited sulfonated organic-inorganic hybrid hydrocarbon polymer is dried under reduced pressure at 50 ° C. to 140 ° C. for 1 to 20 hours. The method according to claim 8, After dissolving the dried sulfonated organic-inorganic hybrid hydrocarbon polymer to methylpyrilidone (NMP) in a ratio of 1 g: 1.5 to 2 ml, the dissolved solution was cast on a glass plate and then at 50 to 140 ° C. for at least 2 hours. The manufacturing method of the diaphragm for vanadium redox-flow secondary batteries characterized by drying. A hydrocarbon membrane (cation exchange membrane) in the form of a film prepared by the method according to any one of claims 8 to 15, having the following chemical molecular formula, wherein the membrane resistance per molar sulfuric acid solution reference is 1.0 Ω · cm ² or less and vanadium resin A vanadium redox-flow secondary battery diaphragm characterized by having an electromotive force of 1.4 V at 100% state of charge when used as a diaphragm for a dox-flow secondary battery. [Chemical molecular formula]

M: n = 1: 1

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