KR102487928B1 - Method of manufacturing multi-stage electrode slurry to improve dispersibility of additive ionomers in electrodes and electrodes for polymer electrolyte fuel cell - Google Patents

Abstract

The present invention relates to a multi-stage electrode slurry manufacturing method for improving the dispersibility of an additive and ionomer in an electrode and to an electrode for a polymer electrolyte fuel cell. The multi-stage electrode slurry manufacturing method for improving the dispersibility of an additive and ionomer in an electrode of the present invention comprises: a first step of mixing an antioxidant and a dispersion solvent; a second step of subdividing nano-sized antioxidant particles in the mixture and performing primary dispersion for uniform dispersion; a third step of mixing the primarily dispersed mixture with a fluorine-based ionomer solution; a fourth step of performing secondary dispersion so that the antioxidant exists at a position adjacent to the ionomer through interaction between the antioxidant particles and the ionomer; a fifth step of preparing a slurry by mixing a water-mixed catalyst with the secondarily dispersed mixture; a sixth step of coating the slurry; and a seventh step of manufacturing an electrode by applying heat to the coated slurry to dry the same, wherein the second step may be performed for improving the efficiency of preventing deterioration and increasing the active area of the antioxidant by physical force through the primary dispersion process and the fourth step may be performed for increasing the degree of freedom of the ionomer polymer in the mixture.

Description

Method of manufacturing multi-stage electrode slurry to improve dispersibility of additive ionomers in electrodes and electrodes for polymer electrolyte fuel cell}

The present invention relates to a method for preparing a multi-step electrode slurry that improves dispersibility of additives and ionomers in an electrode and an electrode for a polymer electrolyte fuel cell. More specifically, in order to increase the anti-deterioration effect of the nanoparticle antioxidant in the electrode, a method of manufacturing the electrode to increase the dispersion of the antioxidant in the electrode and to exist adjacent to the ionomer by adding a pretreatment step of the antioxidant and the ionomer It is about.

In general, a fuel cell generates electrical energy through an electrochemical reaction between hydrogen and oxygen, and continuously produces electricity by supplying hydrogen and oxygen to an anode and a cathode, respectively. It is a development technology.

A fuel cell includes a membrane-electrode assembly (MEA) having an anode catalyst layer and a cathode catalyst layer on both sides of an electrolyte membrane.

Such a catalyst layer may be formed by mixing and dispersing a catalyst slurry containing a catalyst and conductive binder particles, applying the catalyst slurry on a substrate, and transferring the catalyst slurry to an electrolyte membrane in a dry state.

Mixing and dispersibility of the catalyst slurry is important to achieve good performance of the membrane-electrode assembly. When the coating step is performed after the dispersion process, the distribution of the catalyst and the pore structure are determined by acting together with the step of transferring the catalyst layer to the electrolyte membrane, and accordingly, the path through which hydrogen ions, electrons, and water generated in the cathode layer are discharged. is determined

These pathways affect the performance of the fuel cell.

Therefore, when the mixing and dispersion of the catalyst slurry is not uniform and the catalyst and conductive binder particles agglomerate, it is difficult to improve the performance of the fuel cell. Therefore, in the manufacturing process of the membrane-electrode assembly, these problems are solved and It is important to prepare a catalyst slurry that maintains proper mixing and dispersion conditions.

In order for each additive to function properly in a fuel cell electrode, the additive must be present at a target position in the electrode.

When antioxidants, reverse voltage inhibitors, and electrode pore-forming and quality-improving additives are mixed with electrode components at the same time, each component does not exist in the optimal location required, but is present in a random location or uniform dispersion of each component is not achieved. Therefore, it may act as a resistance element in the MEA and lower the performance.

Therefore, there is an increasing need for an electrode slurry manufacturing method capable of solving these problems.

1. Republic of Korea Patent Registration No. 10-1071766 (Method and device for manufacturing catalyst slurry for fuel cells) 2. Korean Patent Registration No. 10-1786674 (catalyst slurry mixing/dispersion device for fuel cells).

Therefore, the present invention has been made to solve the above problems, and the problem to be solved by the present invention is to provide a multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in the electrode and an electrode for a polymer electrolyte fuel cell will be.

Specifically, the present invention is to increase the dispersion of the antioxidant in the electrode by adding a pretreatment step of the antioxidant and the ionomer in order to increase the anti-deterioration effect of the nanoparticle antioxidant in the electrode and to prepare an electrode to exist adjacent to the ionomer By proposing a method, it is intended to solve the conventional problems.

The electrode for a fuel cell manufactured by the method proposed by the present invention can increase the deterioration prevention effect while minimizing the content of the antioxidant and improve the high current performance of the MEA.

In addition, when the process is applied by applying a nano-sized oxidizing material and a metal material in addition to the nanoparticle antioxidant according to the present invention, it is possible to easily discharge water generated in a high current region by securing pores in the electrode.

According to the present invention, since the antioxidant is added for the purpose of preventing deterioration of the ionomer by free radicals in the electrode, it is intended to be placed adjacent to the ionomer.

In addition, nanoparticle antioxidants, even if they are nano-sized particles, exist in agglomerates of several micrometers or more due to the characteristics of nanomaterials. We want to increase the active area.

In addition, the antioxidant is first mixed with the ionomer and combined with the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer to suppress reaggregation of the antioxidant in the slurry.

In addition, when weak physical dispersion is performed after mixing of the ionomer, the degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, thereby improving the dispersibility of the catalyst and ionomer in the slurry to improve the performance of MEA. do.

However, the technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clear to those skilled in the art from the description below. You will be able to understand.

A multi-step electrode slurry manufacturing method for improving the dispersibility of an additive and an ionomer in an electrode related to an embodiment of the present invention for realizing the above object includes a first step of mixing an antioxidant and a dispersion solvent; a second step of subdividing and uniformly dispersing the nano-sized antioxidant particles on the mixture; a third step of mixing the first dispersed mixture with a fluorine-based ionomer solution; a fourth step of performing secondary dispersion so that the antioxidant particles exist adjacent to the ionomer through interaction between the antioxidant particles and the ionomer; a fifth step of preparing a slurry by mixing the catalyst mixed with water and the secondary dispersed mixture; A sixth step of coating the slurry; and a seventh step of fabricating an electrode by applying heat to the coated slurry and drying it, wherein the second step improves anti-deterioration efficiency, and the oxidation by physical force through the primary dispersion process. It is performed to increase the active area of the inhibitor, and the fourth step may be performed to increase the degree of freedom of the ionomer polymer in the mixture.

In addition, the primary dispersion in the second step may be performed through at least one of an ultrasonic generator, the ultrasonic probe, a homogenizer and agitator, and a magnetic stirrer.

In addition, in the fourth step, the secondary dispersion is carried out by at least one of the ultrasonic generator, the ultrasonic probe, the homogenizer, the agitator, the magnetic stirrer, and the planetary mixer. It can be done through one.

In addition, the stirring speed and ultrasonic intensity associated with the secondary dispersion may be lower than the stirring speed and ultrasonic intensity associated with the primary dispersion, and the dispersion time associated with the secondary dispersion may be shorter than the dispersion time associated with the primary dispersion.

In addition, after first mixing the antioxidant particles and the ionomer in the fourth step, by preparing a slurry in the fifth step, the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer is bonded While doing so, re-agglomeration of the antioxidant in the slurry may be inhibited.

In addition, by performing the secondary dispersion at a lower degree than the primary dispersion after mixing the ionomer, the degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, By improving the dispersibility of catalysts and ionomers in slurries, the performance of membrane-electrode assemblies (MEAs) based on these electrodes can be improved.

In addition, in the first step, the antioxidant includes at least one of CeO2, CeZrO4, SnO2, TiO2, MnO2, and MnCO3, and the dispersion solvent is water, methanol, ethanol, n-propanol (n-Propyl alcohol), i-Propanol (i-Propyl alcohol), butanol (Butanol), and ethylene glycol (Ethylene glycol) may include at least one.

In addition, in the first step, at least one of a reverse voltage inhibitor, an electrode porosity forming additive, and a quality improvement additive may be further mixed in addition to the antioxidant.

In addition, in order to improve the dispersion of the antioxidant before the first step, the dried antioxidant powder is pulverized into particles of a predetermined size or more based on a mortar and pestle and / or grinder, and sieve By filtering out particles of a predetermined size or larger using a, it is possible to uniformize the size of the antioxidant powder.

In addition, since the catalyst is ignited when it comes into contact with the dispersion solvent in the fifth step, a catalyst mixed with water may be used to prevent this.

In the fifth step, the preparation of the slurry may be performed using at least one of an ultrasonic generator, an ultrasonic probe, a homogenizer and agitator, and a magnetic stirrer.

In addition, the coating of the slurry in the sixth step may be performed using at least one of a spray, a bar coater, and a slot die coater.

Meanwhile, an electrode for a fuel cell manufactured by the above manufacturing method may be provided.

In order for each additive to function properly in the electrode for a fuel cell, the additive must be present at the target position within the electrode. Conventionally, antioxidants, anti-reverse voltage agents, and additives for electrode porosity and quality improvement are simultaneously mixed with the constituent materials of the electrode. In this case, since each component does not exist in the required optimal position, exists in a random position, or does not uniformly disperse each component, there is a problem of lowering performance by acting as a resistance element in the MEA.

Accordingly, the present invention can solve the above problems by providing a user with an electrode for a polymer electrolyte fuel cell and a method for manufacturing the electrode.

That is, the present invention adds a pretreatment step of the antioxidant and the ionomer in order to increase the anti-deterioration effect of the nanoparticle antioxidant in the electrode to increase the dispersion of the antioxidant in the electrode and prepare the electrode to exist adjacent to the ionomer By providing the method to the user, the conventional problems can be solved.

The electrode for a fuel cell manufactured in this way can increase the deterioration prevention effect while minimizing the content of the antioxidant, and has an effect of improving the high current performance of the MEA.

In addition, when the process is applied by applying a nano-sized oxidizing material and a metal material in addition to the nanoparticle antioxidant, there is an effect of facilitating water discharge in a high current region by securing pores in the electrode.

In addition, even nano-sized particles, nanoparticle antioxidants exist in agglomerates of several micrometers or more due to the characteristics of nanomaterials. When strong physical force is applied through the pre-dispersion process, the agglomerated particles are broken into small particles and act as antioxidants. active area can be increased.

In addition, if the antioxidant is first mixed with the ionomer, re-aggregation of the antioxidant in the slurry can be suppressed while binding to the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer.

In addition, when weak ultrasonic dispersion is performed after mixing the ionomer, the degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, improving the dispersibility of the catalyst and ionomer in the slurry, thereby improving the performance of MEA. there is.

On the other hand, the effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

1 is a flow chart illustrating a multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode according to the present invention.
2 and 3 are views for explaining that an additional step is performed in the method of FIG. 1 .
Figure 4 shows a schematic diagram of the material position change in the electrode according to the electrode slurry manufacturing method according to the present invention.
5 shows particle size analysis (PSA) of slurry produced through a multi-step dispersion process according to the present invention.
6 shows single cell performance improvement through a multi-step dispersion process according to the present invention.
7 shows voltage changes before and after OCV Holding accelerated deterioration test (AST) according to the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. However, since the description of the present invention is only an embodiment for structural or functional description, the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, since the embodiment can be changed in various ways and can have various forms, it should be understood that the scope of the present invention includes equivalents capable of realizing the technical idea. In addition, since the object or effect presented in the present invention does not mean that a specific embodiment should include all of them or only such effects, the scope of the present invention should not be construed as being limited thereto.

The meaning of terms described in the present invention should be understood as follows.

Terms such as "first" and "second" are used to distinguish one component from another, and the scope of rights should not be limited by these terms. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element. It should be understood that when an element is referred to as “connected” to another element, it may be directly connected to the other element, but other elements may exist in the middle. On the other hand, when an element is referred to as being “directly connected” to another element, it should be understood that no intervening elements exist. Meanwhile, other expressions describing the relationship between components, such as “between” and “immediately between” or “adjacent to” and “directly adjacent to” should be interpreted similarly.

Singular expressions should be understood to include plural expressions unless the context clearly dictates otherwise, and terms such as “comprise” or “having” refer to a described feature, number, step, operation, component, part, or It should be understood that it is intended to indicate that a combination exists, and does not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs, unless defined otherwise. Terms defined in commonly used dictionaries should be interpreted as consistent with meanings in the context of related art, and cannot be interpreted as having ideal or excessively formal meanings unless explicitly defined in the present invention.

Method for manufacturing multi-step electrode slurry to improve dispersibility of additives and ionomers in electrodes

1 is a flow chart illustrating a multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode according to the present invention.

Referring to Figure 1, first, the step (S10) of mixing the antioxidant and the dispersion solvent proceeds.

In step S10, the antioxidant may include at least one of CeO2, CeZrO4, SnO2, TiO2, MnCO3, and MnO2.

In step S10, the dispersion solvent is water, methanol, ethanol, n-propanol, i-Propyl alcohol, butanol and ethylene glycol may include at least one of them.

In step S10, at least one of a reverse voltage inhibitor, an electrode pore forming additive, and a quality improvement additive may be further mixed in addition to the antioxidant.

Thereafter, a step (S20) of subdividing the nano-sized antioxidant particles on the mixture and performing primary dispersion to uniformly disperse them proceeds.

Step S20 is performed to improve the anti-deterioration efficiency and increase the active area of the antioxidant by physical force through the primary dispersion process.

In step S20, the primary dispersion may be performed through at least one of an ultrasonic generator, an ultrasonic probe, a homogenizer and an agitator, and a magnetic stirrer.

In addition, a step (S30) of mixing the first dispersed mixture and the fluorine-based ionomer solution is performed.

In addition, a step (S40) of performing secondary dispersion so that the antioxidant particles exist adjacent to the ionomer through the interaction between the antioxidant particles and the ionomer is performed.

Step S40 is performed to increase the degree of freedom of the ionomer polymer in the mixture.

In step S40, the secondary dispersion is performed through at least one of an ultrasonic generator, the ultrasonic probe, the homogenizer, the agitator, a planetary mixer, and a magnetic stirrer. can

The stirring speed and ultrasonic intensity associated with the secondary dispersion may be lower than the stirring speed and ultrasonic intensity associated with the primary dispersion, and the dispersion time associated with the secondary dispersion may be shorter than the dispersion time associated with the primary dispersion.

In this way, by performing the secondary dispersion at a lower degree than the primary dispersion after mixing the ionomer, the degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, resulting in the slurry By improving the dispersibility of the catalyst and ionomer in the membrane-electrode assembly (MEA) based on the electrode, the performance can be improved.

In addition, a step (S50) of preparing a slurry by mixing the catalyst mixed with water and the secondary dispersed mixture is performed.

After first mixing the antioxidant particles and the ionomer through step S40, through preparing a slurry in step S50, while combining with the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer, the oxidation in the slurry Reagglomeration of the inhibitor can be inhibited.

In step S50, the preparation of the slurry may be performed through at least one of an ultrasonic generator, the ultrasonic probe, a homogenizer and agitator, and a magnetic stirrer.

In addition, the step of coating the slurry (S60) and applying heat to the coated slurry to dry it, thereby proceeding with the step of manufacturing the electrode (S70).

In step S60, the coating of the slurry may be performed using at least one of a spray, a bar coater, and a slot die coater.

Meanwhile, FIGS. 2 and 3 are views for explaining that an additional step is performed in the method of FIG. 1 .

Referring to FIG. 2, in order to improve the dispersion of the antioxidant before step S10, the dried antioxidant powder is pulverized into particles of a predetermined size or more based on a mortar and pestle and / or grinder, and a sieve ( A step (S5) of uniformizing the size of the antioxidant powder by filtering out particles having a predetermined size or more using a Sieve) may be added.

In addition, referring to FIG. 3 , before step S50, since the catalyst is ignited upon contact with the dispersion solvent, step S100 in which water and catalyst are mixed may be separately performed to prevent this.

Step S100 is performed independently of each step S10 to S40.

The steps proposed by the present invention are briefly summarized as follows.

[Step S10] Antioxidant + dispersion solvent mixing

- Antioxidants: CeO2, CeZrO4, SnO2, TiO2, MnCO3, MnO2, etc.

- In addition to antioxidants, additives such as reverse voltage inhibitors (reverse voltage inhibitors, electrode quality improvers, performance improvers, etc.) can be applied

- In order to improve the dispersion of antioxidants, before mixing with a solvent, the dried powder can be ground into large particles using a pestle/mortle bowl, grinder, etc., and filtered using a sieve to make the powder size uniform.

- Dispersion solvent: water, alcohol (Methanol, Ethanol, n-Propyl alcohol, i-Propyl alcohol, Butanol, Ethylene glycol, etc.) single solvent or mixed solvent

[Step S20] 1st dispersion

- For the purpose of subdividing and uniformly dispersing nano-sized antioxidant particles to improve anti-deterioration efficiency

- Dispersing equipment: ultrasonic generator, ultrasonic probe, homogenizer, high-pressure homogenizer, high-speed stirrer, magnetic stirrer

[Step S30] Fluorine-based ionomer solution mixing

[Step S40] Secondary dispersion

- The purpose of increasing the degree of freedom of the ionomer polymer and allowing the antioxidant to exist adjacent to the ionomer through the interaction between the antioxidant particles and the ionomer

- Dispersing equipment: ultrasonic generator, ultrasonic probe, homogenizer, high-pressure homogenizer, high-speed stirrer, idling mixer, magnetic stirrer

- 2nd dispersion has lower dispersion intensity than 1st dispersion (stirring speed or ultrasonic intensity or dispersion time)

[Separate Independent Step (S100)] Catalyst + Water Mixing

- The catalyst is ignited when it comes into contact with an alcohol solvent, so to prevent this, the catalyst is wetted with water (wetting)

[Step S50] Prepare a slurry by mixing the second dispersed solution with the S100 catalyst

- Slurry mixing method: ultrasonic generator, ultrasonic probe, homogenizer, high-pressure homogenizer, high-speed stirrer

[Step S60] Slurry coating method for electrode manufacturing

- Spray, bar coater, slot die coater

[Step S70] Electrode production

- Dry the coated slurry by applying heat to produce an electrode

Experiment result

Figure 4 shows a schematic diagram of the material position change in the electrode according to the electrode slurry manufacturing method.

4 (a) shows an electrode manufactured by an existing mixing process, and (b) shows an electrode manufactured by adding an ultrasonic pretreatment process of an antioxidant and an ionomer solution according to the present invention.

In addition, 10 represents a nanoparticle antioxidant, 20 represents a Pt/C catalyst, and 30 represents a PFSA fluorine-based ionomer.

Referring to (a) of FIG. 4, in the case of the conventional method, the dispersion of the ionomer 30, the catalyst 20, and the antioxidant 10 is very low, and the antioxidant 10 is aggregated and present at random locations. can confirm that

On the other hand, referring to (b) of FIG. 4 according to the present invention, the degree of freedom of the polymer of the ionomer 30 is high, so it is more flexible, and the antioxidant 10 is dispersed and present in a position adjacent to the ionomer 30 in a small size. can confirm that

In addition, it can be confirmed that the degree of dispersion of the catalyst 20 is also increased by the dispersion of the ionomer 30.

The particle dispersion and single cell performance of the electrode manufactured through the multi-step dispersion process will be described based on FIGS. 5 and 6,

5 shows particle size analysis (PSA) of slurry produced through a multi-step dispersion process according to the present invention.

Figure 5 (b) shows the size and % Tile of the Ref and the multi-step dispersion process.

In addition, (a) of FIG. 5 shows the results of the particle size analysis of Ref and the slurry of the multi-step dispersion process.

As a result, as shown in (a) of FIG. 5, it can be confirmed that the particle size of the slurry is reduced (D50 and D90 are reduced).

6 shows single cell performance improvement through a multi-step dispersion process according to the present invention.

Referring to FIG. 6, Ref and the multi-stage dispersion process are compared, and it can be confirmed that the multi-stage dispersion process improves the MEA performance.

That is, it can be clearly confirmed that a high current is generated at the same voltage.

The results of the accelerated deterioration test of the electrode manufactured through the multi-step dispersion process will be described with reference to FIG. 7 .

7 shows voltage changes before and after OCV Holding accelerated aging test (AST).

Referring to FIG. 7 , changes in cell electrodes before and after AST evaluation are shown.

This is a method for evaluating MEA Chemical Stability and Metrics among DOE's PEM Fuel Cell Testing Protocol, and is a method for evaluating ionomer deterioration of electrolyte membranes and electrodes.

The results of FIG. 7 were conducted under the following conditions.

- Cell temperature: 90℃

- Relative Humidity: Cathode 30%, Anode 30%

- Evaluation condition: OCV maintenance

- Evaluation time: 500 hours

7 shows a comparison of cell voltage changes before and after 500 hours under the above conditions.

Referring to FIG. 7, it can be clearly seen that the ionomer degradation is much less (-18.6% VS -6.51%) compared to Ref and the multi-step dispersion process according to the present invention.

Effect according to the present invention

In order for each additive to function properly in the electrode for a fuel cell, the additive must be present at the target position within the electrode. Conventionally, antioxidants, anti-reverse voltage agents, and additives for electrode porosity and quality improvement are simultaneously mixed with the constituent materials of the electrode. In this case, since each component does not exist in the required optimal position, exists in a random position, or does not uniformly disperse each component, there is a problem of lowering performance by acting as a resistance element in the MEA.

The present invention can solve the above problems by providing a user with an electrode for a polymer electrolyte fuel cell and a method for manufacturing the electrode.

That is, the present invention adds a pretreatment step of the antioxidant and the ionomer in order to increase the anti-deterioration effect of the nanoparticle antioxidant in the electrode to increase the dispersion of the antioxidant in the electrode and prepare the electrode to exist adjacent to the ionomer By providing the method to the user, the conventional problems can be solved.

The electrode for a fuel cell manufactured in this way can increase the deterioration prevention effect while minimizing the content of the antioxidant, and has an effect of improving the high current performance of the MEA.

In addition, when the process is applied by applying a nano-sized oxidizing material and a metal material in addition to the nanoparticle antioxidant, there is an effect of facilitating water discharge in a high current region by securing pores in the electrode.

In addition, even nano-sized particles, nanoparticle antioxidants exist in agglomerates of several micrometers or more due to the characteristics of nanomaterials. When strong physical force is applied through the pre-dispersion process, the agglomerated particles are broken into small particles and act as antioxidants. active area can be increased.

In addition, if the antioxidant is first mixed with the ionomer, re-aggregation of the antioxidant in the slurry can be suppressed while binding to the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer.

In addition, if weak physical dispersion is performed after mixing of the ionomer, the degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, thereby improving the dispersibility of the catalyst and ionomer in the slurry, thereby improving the performance of MEA. there is.

On the other hand, the effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

In addition, the above-described system and its control method are not limited to the configuration and method of the above-described embodiments, but all or part of each of the embodiments is optional so that various modifications can be made. It may be configured in combination with.

Claims (13)

A first step of mixing an antioxidant and a dispersion solvent;
a second step of subdividing and uniformly dispersing the nano-sized antioxidant particles on the mixture;
a third step of mixing the first dispersed mixture with a fluorine-based ionomer solution;
a fourth step of performing secondary dispersion so that the antioxidant particles exist adjacent to the ionomer through interaction between the antioxidant particles and the ionomer;
a fifth step of preparing a slurry by mixing the catalyst mixed with water and the secondary dispersed mixture;
A sixth step of coating the slurry; and
A seventh step of manufacturing an electrode by applying heat to the coated slurry and drying it;
The second step is performed to improve the anti-deterioration efficiency and increase the active area of the antioxidant by physical force through the primary dispersion process,
The fourth step is performed to increase the degree of freedom of the ionomer polymer in the mixture,

The stirring speed and ultrasonic intensity related to the secondary dispersion are lower than the stirring speed and ultrasonic intensity related to the primary dispersion,
The dispersion time associated with the secondary dispersion is shorter than the dispersion time associated with the primary dispersion,

After first mixing the antioxidant particles and the ionomer through the fourth step, through preparing a slurry in the fifth step,
While binding to the -SO ₃ functional group of the side chain of the PFSA fluorine-based ionomer, reaggregation of the antioxidant in the slurry is suppressed,

By performing the secondary dispersion to a lower degree than the primary dispersion after mixing the ionomer,
The degree of freedom of the ionomer polymer increases and the electrostatic repulsive force due to the charge of the functional group of the side chain increases, thereby improving the dispersibility of the catalyst and the ionomer in the slurry, thereby a membrane-electrode assembly based on the electrode ( MEA) performance is improved,

In the first step above
The antioxidant,

includes at least one of
The dispersion solvent is at least one of water, methanol, ethanol, n-propanol, i-propanol, butanol, and ethylene glycol. A multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode comprising one.
According to claim 1,
In the second step, the first dispersion,
A multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode performed through at least one of an ultrasonic generator, an ultrasonic probe, a homogenizer, and an agitator.
According to claim 2,
In the fourth step, the secondary dispersion,
Improving the dispersibility of additives and ionomers in electrodes performed through at least one of an ultrasonic generator, an ultrasonic probe, a homogenizer, an agitator, a planetary mixer, and a magnetic stirrer Multi-step electrode slurry manufacturing method.
delete delete delete delete According to claim 3,
In the first step, a multi-step electrode slurry manufacturing method for improving the dispersibility of an additive and an ionomer in an electrode in which at least one of a reverse voltage inhibitor, an electrode pore forming and quality improving additive is further mixed in addition to the antioxidant.
According to claim 8,
In order to improve the dispersion of the antioxidant before the first step,
The dried antioxidant powder is pulverized into particles of a predetermined size or larger based on a mortar and pestle and/or a grinder, and sieving particles of a predetermined size or larger using a sieve to obtain the antioxidant powder. A multi-step electrode slurry manufacturing method that improves the dispersibility of additives and ionomers in an electrode that uniformizes the size.
According to claim 9,
In the 5th step above
Since the catalyst is ignited when in contact with the dispersion solvent, a multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode in which the catalyst mixed with the water is used to prevent this. According to claim 10,
In the fifth step, the preparation of the slurry is
A multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode performed through at least one of an ultrasonic generator, an ultrasonic probe, a homogenizer and an agitator, and a magnetic stirrer.
According to claim 11,
In the sixth step, the coating of the slurry,
A multi-step electrode slurry manufacturing method for improving the dispersibility of additives and ionomers in an electrode performed using at least one of a spray, a bar coater, and a slot die coater. An electrode for a fuel cell manufactured by the manufacturing method of any one of claims 1 to 3 and 8 to 12.

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