KR102415844B1 - Separator consisting of lead and Unitized Regenerative Fuel Cell comprising the separator - Google Patents

Abstract

The present invention relates to a bipolar plate technology for an integrated reversible fuel cell, and more particularly, it includes a bipolar plate made of lead that can be applied instead of a metal plate or a carbon plate used as a bipolar plate in an existing integrated reversible fuel cell, and the bipolar plate It relates to an integrated reversible fuel cell.

Description

Bipolar plate composed of lead and an integrated reversible fuel cell comprising the bipolar plate

The present invention relates to a bipolar plate technology for an integrated reversible fuel cell, and more specifically, to a bipolar plate made of lead that can be applied instead of a metal plate or carbon plate used as a bipolar plate in an existing integrated reversible fuel cell, and the bipolar plate. It relates to an integrated reversible fuel cell.

In the past few decades, fuel cells have received considerable attention as electrochemical energy conversion systems for generating electricity. Among the numerous types of fuel cell devices, unitized reenerative fuel cells (URFCs) operate in water electrolyzer (WE) and fuel cell (FC) modes to convert reciprocating energy (2H ₂ O ↔) 4H ⁺ + O ₂ + 4e ^- ) as an eco-friendly hydrogen energy storage system with high energy efficiency and long-term cycle, it has attracted considerable attention and interest due to its high reciprocal energy conversion efficiency with high energy density.

During unit cell (FC mode) operation in a URFC system, the by-product is water (2H ₂ + O ₂ → 2H ₂ O) with no greenhouse gas emissions. The reverse reaction of FC mode occurs during WE mode in URFC systems. Bipolar plates are one of the most important components in PEMFC (Polymer Electrolyte Membrane Fuel Cell) and URFC systems, and are known as multifunctional components in unit cell devices. In multi-stack URFC systems, bipolar plates are used to separate individual cells, support membrane electrode assemblies, and attach each cell in series. It also plays an important role as an electron transporter and fuel distributor during unit cell operation of URFCs.

In general, carbon plates or metal plates are used as bipolar plates in integrated reversible fuel cells, but typical carbon bipolar plates have stability-related problems. V) and/or high acidic conditions at high temperature are the main problems that must be overcome to improve URFC performance. Due to the disadvantages of the carbon plate, when using a known metal plate made of stainless steel or the like, conductivity is improved, but there is a problem in that it is weak to corrosion, heavy, and expensive.

Therefore, in order to solve these problems, a bipolar plate with a new structure suitable for use as a bipolar plate for an integrated reversible fuel cell with high conductivity, stability at high temperature, excellent corrosion resistance, light weight than existing metal plates, and low cost was developed. needed to be

Korean Patent Publication No. 10-2008-0109148

As a result of research efforts to solve the above problems, the present inventors have completed the present invention by developing a technology for applying a Pb metal sheet to an integrated reversible fuel cell bipolar plate.

Therefore, an object of the present invention is to reduce the weight by using a lead metal sheet made of pure lead instead of a metal plate or carbon plate used as a bipolar plate in an existing fuel cell, and to reduce the manufacturing cost because it is flexible and easy to design and process the flow path. An object of the present invention is to provide a bipolar plate for an integrated reversible fuel cell that can contribute to commercialization of a fuel cell system by reducing the cost and an integrated reversible fuel cell including the bipolar plate.

Another object of the present invention is that the hydrophobicity of the surface of the bipolar plate can be reduced, so that the contact resistance can be reduced, it is advantageous for mass transfer, and the amount of moisture over-flooding the electrode can be effectively discharged. To provide a bipolar plate for an integrated reversible fuel cell capable of maintaining high cell performance with low interfacial resistance due to high conductivity and an integrated reversible fuel cell including the bipolar plate.

Objects of the present invention are not limited to the objects mentioned above, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the object of the present invention described above, the present invention is a metal plate composed of lead; and a flow path formed on at least one surface of the metal plate.

In a preferred embodiment, a metal coating layer formed on the surface of the metal plate on which the flow path is formed; further includes.

In a preferred embodiment, the metal coating layer is formed including any one selected from the group consisting of Ag, Pt, Au, Ni, Cr, and Sn, or one or more of oxides, carbides, and nitrides of these metals.

In a preferred embodiment, the metal plate is a Pb metal sheet, and the flow path has a depth of 1/4 or more and 2/3 or less of the thickness of the metal plate.

In a preferred embodiment, the water contact angle of the metal coating layer is 77° or more.

In addition, the present invention comprises the steps of polishing the surface of the lead plate; forming a flow path on at least one surface of the polished lead plate to a depth of 1/4 or more and 2/3 or less of the thickness of the lead plate; and pre-treating the lead plate having the flow path formed thereon.

In a preferred embodiment, forming a metal coating layer on the surface of the pre-treated lead plate; further comprises.

In a preferred embodiment, the channel is a serpentine structure.

In a preferred embodiment, the pretreatment includes a first water washing step of the lead plate in which the flow path is formed; a first acid treatment step of immersing the first water-washed lead plate in an acidic solution; a secondary acid treatment step of immersing the first acid-treated lead plate in another acidic solution; a secondary water washing step of washing the secondary acid-treated lead plate; and a drying step of drying the second washed lead plate.

In a preferred embodiment, the acidic solution used in the first acid treatment step is an oxalic acid solution, and the acidic solution used in the second acid treatment step is a sulfuric acid solution.

In a preferred embodiment, the step of forming the metal coating layer comprises the steps of immersing the pre-treated lead plate in a coating solution; forming a metal coating layer by electrodepositing metal ions dissolved in the coating solution on the surface of the lead plate by applying an electric field to the immersed lead plate; and a post-treatment step of washing and drying the lead plate on which the metal coating layer is formed.

In addition, the present invention provides an integrated reversible fuel cell including any one of the above-mentioned bipolar plates or a bipolar plate manufactured by any one of the above-mentioned manufacturing methods.

In a preferred embodiment, as the thickness of the coating layer formed on the surface of the bipolar plate increases, the water contact angle increases.

In addition, the present invention provides a secondary battery including any one of the above-mentioned bipolar plate or the bipolar plate manufactured by any one of the above-described manufacturing methods as a current collector.

In a preferred embodiment, the secondary battery is a redox flow battery.

According to the present invention described above, by using a lead metal sheet made of pure lead as a bipolar plate for an integrated reversible fuel cell instead of a conventional metal plate or carbon plate used as a bipolar plate in an existing fuel cell, it is possible to reduce weight and design a flow path due to flexibility. And since it is easy to process, manufacturing costs can be reduced, which can contribute to the commercialization of fuel cell systems.

In addition, according to the present invention, the hydrophobicity of the surface of the bipolar plate is high, so that the contact resistance can be reduced, it is advantageous for mass transfer, and it is possible to effectively discharge the amount of moisture over-flooding the electrode, so it has excellent corrosion resistance and excellent performance stability during long-term operation. , high conductivity, low interfacial resistance, and high cell performance.

This technical effect of the present invention is not limited only to the range mentioned above, and even if not explicitly mentioned, the effect of the invention that can be recognized by a person of ordinary skill in the art from the description of the specific content for the implementation of the invention to be described later is also of course included

1 is a schematic exploded perspective view of a known separator for a fuel cell and a stack structure based thereon.
2A is a design diagram of a bipolar plate for an integrated regenerative fuel cell according to embodiments of the present invention, and FIG. 2B is a partial longitudinal cross-sectional view of the bipolar plate having a flow path shown in FIG. 2A, and FIG. 2C. shows a part of a longitudinal cross-sectional view according to another embodiment of a bipolar plate having a flow path shown in FIG. 2A .
3A is an XRD spectrum of a Pb bipolar plate made of lead and an Ag-Pb bipolar plate in which a silver coating layer is formed on the Pb bipolar plate, and FIG. 3B is an XPS spectrum according to embodiments of the present invention.
4A is an SEM micrograph image (ae) and EDAX element mapping analysis result (fh) of a Pb bipolar plate and an Ag-Pb bipolar plate according to embodiments of the present invention, and FIG. 4B is an EDAX spectrum.
5, (a) and (b) respectively show the water contact angles of the Pb bipolar plate and the Ag-Pb bipolar plate according to the embodiments of the present invention, and (c) is a graph comparing the measured data.
6, (a) and (b) show the CV analysis results of the Pb bipolar plate and the Ag-Pb bipolar plate according to the embodiments of the present invention, respectively, (c) is the Pb bipolar plate and the Ag-Pb bipolar plate It is a graph showing the measurement result of the corrosion test of

The terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification is present, and includes one or more other features or It should be understood that the existence or addition of numbers, steps, operations, components, parts, or combinations thereof does not preclude the possibility of addition.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present invention, it should not be interpreted in an ideal or excessively formal meaning. does not

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

However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Like reference numbers used to describe the invention throughout the specification refer to like elements.

A technical feature of the present invention is that a lead metal sheet made of pure lead is used as a bipolar plate for an integrated reversible fuel cell instead of a metal plate or carbon plate used as a bipolar plate in an existing fuel cell. In other words, by using a lead (Pb) plate that can withstand well in sulfuric acid electrolyte as a bipolar plate, strong corrosion resistance in acid electrolyte solution and corrosion occurring in carbon plate can be prevented. It is because the flexibility which is easy to process can be acquired. Moreover, due to the high hydrophobicity of the bipolar plate surface, contact resistance can be reduced and it is advantageous for mass transfer, and it can effectively discharge the amount of over-flooding moisture in the electrode, so it has excellent corrosion resistance, excellent performance stability during long-term operation, and high conductivity The resistance is low and the cell performance can be kept high.

Accordingly, the bipolar plate of the present invention includes a metal plate made of lead; and a flow path formed on at least one surface of the metal plate. Here, the metal plate is not limited as long as it is a lead metal plate having the same active area as the thickness of 2T MEA, but may be a 1T Pb metal sheet as an embodiment. The flow path formed in the bipolar plate may be implemented to have a depth of 1/4 or more and 2/3 or less of the thickness of the metal plate, and may have a serpentine structure as shown in FIG. 2A as an embodiment.

If necessary, a metal coating layer formed on the surface of the metal plate on which the flow path is formed; may further include. The metal coating layer may be formed including any one selected from the group consisting of Ag, Pt, Au, Ni, Cr, Sn, or one or more of oxides, carbides, and nitrides of these metals. When the thickness of the coating layer becomes thick, the bipolar plate The hydrophobicity of the surface, that is, the magnitude of the water contact angle can be improved. As an embodiment, when the metal coating layer is formed, the water contact angle on the surface of the bipolar plate is at least 77°, which is the water contact angle of the bipolar plate made of lead, and may be formed to be 90° or more if necessary. On the other hand, the water contact angle is important to ensure the interaction between the bipolar plate material and water molecules, and the high water adsorption of the bipolar plate can significantly change the URFC unit cell performance. In other words, the presence of a higher amount of water molecules on the bipolar plate not only affects the electrode performance, reduces fuel distribution, and causes several problems such as lowering the overall electrochemical performance, but most importantly, water molecules on the surface of the bipolar plate If the adsorption rate of URFC is high, the decomposition (corrosion) rate can be significantly increased, which is a major disadvantage of the URFC system. Therefore, in the present invention, the accumulation of water molecules on the bipolar plate surface can be effectively controlled by modifying the surface to have hydrophobicity using the metal coating layer and controlling the thickness of the metal coating layer.

By using these characteristics, the bipolar plate of the present invention can effectively perform the role of a current collector in a secondary battery field, which is a system to which an electric field is applied during a charging/discharging process such as a redox flow battery.

In addition, the bipolar plate manufacturing method of the present invention comprises the steps of polishing the surface of the lead plate; forming a flow path on at least one surface of the polished lead plate to a depth of 1/2 or more and 2/3 or less of the thickness of the lead plate; and pre-treating the lead plate on which the flow path is formed. If necessary, forming a metal coating layer on the surface of the pre-treated lead plate; may further include.

Here, the pre-treatment is a first water washing step of the lead plate formed with the flow path; a first acid treatment step of immersing the first water-washed lead plate in an acidic solution; a secondary acid treatment step of immersing the first acid-treated lead plate in another acidic solution; a secondary water washing step of washing the secondary acid-treated lead plate; and a drying step of drying the second washed lead plate; as an embodiment, the acidic solution used in the first acid treatment step is an oxalic acid solution, and the acidic solution used in the second acid treatment step is sulfuric acid It may be a solution.

Forming the metal coating layer may include immersing the pretreated lead plate in a coating solution; forming a metal coating layer by electrodepositing metal ions dissolved in the coating solution on the surface of the lead plate by applying an electric field to the immersed lead plate; and a post-treatment step of washing and drying the lead plate on which the metal coating layer is formed.

In addition, the integrated reversible fuel cell of the present invention may include, as a bipolar plate, a lead metal plate or a lead metal plate having a metal coating layer formed thereon as described above. There is no need to manufacture the compounding required to manufacture the carbon plate during manufacturing, and it has excellent flexibility and workability, so it is lighter than other metal plates and has strong corrosion resistance, and it is economical because it can simplify the flow path plate design process.

Example 1

A Pb bipolar plate having a design diagram shown in FIG. 2A and a cross-sectional view of the structure shown in FIG. 2B was manufactured in the following manner.

1. Abrasive processing step

The surface of a 1 mm thick Pb plate (area 10x10 cm 2 ) was polished.

2. Forming a flow path

A serpentine structure flow path was processed to a depth of 0.6 mm on the surface of the polished Pb plate, and round processing was performed.

3. Preprocessing Steps

The Pb plate in which the flow path was formed was washed with water at 60°C for 30 minutes, and immersed in oxalic acid conditions at 60°C for 30 minutes. Thereafter, after treatment in 5M sulfuric acid solution at 60°C for 30 minutes, and finally washed with water at 60°C and dried, a Pb bipolar plate was prepared.

Example 2

The Pb bipolar plate prepared in Example 1 was treated as follows to prepare an Ag-Pb bipolar plate having a schematic diagram shown in FIG. 2A and a cross-sectional view of the structure shown in FIG. 2C.

The Pb bipolar plate was immersed in an Ag precursor solution (AgNO 3 solution), and an electric field (5 mA/cm 2 )) was applied to both edges in the immersed state to electrodeposit Ag on the surface of the Pb bipolar plate. Thereafter, the Ag-Pb bipolar plate was prepared by washing and drying the plate on which the Ag coating layer was formed.

Experimental Example 1

The crystal structures of the Pb bipolar plate obtained in Example 1 and the Ag-Pb bipolar plate obtained in Example 2 were analyzed by X-ray diffraction method (XRD, using a Bruker Advance D8 diffractometer), and X-ray photoelectron spectroscopy (XPS, MultiLab) 2000) to investigate the chemical composition and state of each sample by performing XPS, and the results are shown in FIGS. 3A and 3B, respectively.

Figure 3a shows the XRD spectra of the Pb bipolar plate and the Ag-Pb bipolar plate. For the Pb bipolar plate, the diffraction peaks (2θ) were observed at 31.33°, 36.32°, 52.29°, 62.24°, 65.33° and 77.17°, which are (111), (200), (220), (311), (222) and (400) with respect to the reflection grating plane. Therefore, it was confirmed that the Pb bipolar plate diffraction peak corresponds to a face-centered cubic (FCC) crystal structure (JCPDS card number: 02-0799). More interestingly, the peak intensity behavior was changed after coating Ag on the Pb bipolar plate surface as shown in Fig. 3a. It was observed that the Pb diffraction peak was significantly minimized in the Ag-Pb bipolar plate. Instead, a new additional diffraction peak of Ag with higher intensity was observed because the Ag layer was uniformly coated on the surface of the Pb bipolar plate. The diffraction peaks (2θ) of Ag were observed at 38.22°, 44.41°, 64.56° and 77.46°, which correspond to the reflection grating planes of (111), (200), (220) and (311), respectively. The diffraction peak of Ag corresponds to the FCC structure (JCPDS card number: 04-0783). In addition, the low intensity Pb diffraction peak corresponds to the FCC structure of the Pb bipolar plate. The reduced diffraction intensity of the Pb peak appears to be due to the coating of the Ag layer on the surface of the Pb bipolar plate. Therefore, the successful coating of the Ag layer on the Pb substrate could be confirmed from the XRD analysis.

Figure 3b shows the XPS spectra of the Pb bipolar plate and the Ag-Pb bipolar plate. The high-resolution deconvolution XPS spectra of the Pb bipolar plate and Ag-Pb bipolar plate are shown in Figs. S1 and S2, respectively. In the recorded XPS spectra of the Pb bipolar plate, the most dominant peaks were observed at binding energies of 142.4 and 137.4 eV, which correspond to the Pb 4f peaks of Pb 4f5/2 and Pb 4f7/2, respectively. After coating the Ag layer on the Pb bipolar plate, the intensity of the observed Pb peaks at 142.4 and 137.4 eV was significantly reduced. This decrease in Pb peak intensity is mainly due to the presence of a thick coating layer of other materials on the Pb surface. The two new predominant peaks observed at binding energies of 368 and 374 eV correspond to Ag 3d5/2 and Ag 3d3/2, respectively, and are attributed to Ag. In the XPS spectrum of Ag-Pb bipolar plate, the peak intensity of Ag 3d is much higher than that of Pb 4f. This appears to be due to the presence of an Ag layer on the Pb surface. Therefore, the XPS results of the Pb bipolar plate and the Ag-Pb bipolar plate show that Ag was uniformly coated on the surface of the Pb bipolar plate.

Experimental Example 2

The surface morphology of the Pb bipolar plate obtained in Example 1 and the Ag-Pb bipolar plate obtained in Example 2 and the presence of a coating layer coated on the surface were analyzed using SEM and EDAX analysis, and the results are shown in FIGS. 4a and 4b. indicated. Here, the surface morphology of the bipolar plate was analyzed using a scanning electron microscope (SEM, HITACHI, SU-70). Energy dispersive X-ray spectroscopy (EDAX) elemental analysis data and mapping were used to further confirm the presence of surface coatings.

The SEM micrograph images and EDAX mapping profiles of the Pb bipolar plate and Ag-Pb bipolar plate are shown in Figs. 4a and 4b (a-c) and (d-i), respectively. Prior to SEM, the surface of the bipolar plate was cleaned to remove impurities. As shown in (a-c) of Fig. 4a, only Pb elements were observed in the mapping profile; This confirms that the source material is Pb. In contrast, after coating the Ag layer on the Pb-Ag bipolar plate, a smooth surface was observed as shown in Fig. 4a(d) and (e). In addition, EDAX element mapping analysis was performed on Ag-Pb bipolar plates, and the corresponding results are shown in Fig. 4a (f-h). From (g) and (h) of Fig. 4a, it is clear that Ag ultimately appears on the entire surface of the Pb bipolar plate as a homogeneous coating layer. Due to this coated layer, not much Pb is observed on the surface. In addition, (i) and (j) of Fig. 4b, which is the result of EDAX pattern analysis, shows the EDAX spectra of the Pb bipolar plate and the Ag-coated Pb bipolar plate, respectively. The most observed elemental peak in Fig. 4b(i) is due to the Pb metal. However, this peak was significantly suppressed after coating Ag on the surface of the Pb bipolar plate as shown in Fig. 4b(j). The coexistence of most of the peaks corresponds to Pb and Ag elements, confirming that Ag was uniformly and effectively coated on the surface of the Pb bipolar plate.

Considering that the performance of the URFC is also related to the surface properties of the bipolar plate, it can be confirmed that the Ag-Pb bipolar plate of the present invention can be advantageous for the electrochemical reaction occurring during the reciprocal energy conversion in the URFC system.

Experimental Example 3

The water contact angle was measured using a GSA-X instrument (SurfaceTech Co., Ltd., Korea) on the surfaces of the Pb bipolar plate obtained in Example 1 and the Ag-Pb bipolar plate obtained in Example 2, and the results are shown. 5 is shown.

In FIG. 5, (a) is the water contact angle of the Pb bipolar plate surface, (b) is the water contact angle of the Ag-Pb bipolar plate surface, and (c) is a comparison of the data of the Pb bipolar plate and the Ag-Pb bipolar plate. As shown in (a), water droplets adhere to the surface of the Pb bipolar plate. However, the water adsorption behavior on the surface of the Ag-Pb bipolar plate was significantly different from the water adsorption behavior of the Pb bipolar plate as observed in Fig. 5(b), indicating an increase in the contact angle. The identified water contact angle data of the bipolar plate material are shown in Figure 5, and the corresponding water contact angle values of the Pb bipolar plate and Ag-Pb bipolar plate were observed to be 77.83° and 92.21°, respectively. This proves that the water contact angle of the Pb bipolar plate can be significantly improved by coating Ag on the surface of the Pb bipolar plate. A high water contact angle offers many advantages, including improved corrosion resistance. In addition, it was observed that the water contact angle of the Ag-Pb bipolar plate was increased when the coating thickness of Ag formed on the surface of the Pb bipolar plate was increased. Therefore, the water contact angle can be changed by changing the type, thickness, and process of the metal coating layer formed on the surface of the Pb bipolar plate, so that, if necessary, the hydrophobicity of the surface of the bipolar plate can be controlled as desired. In particular, when the hydrophobicity of the surface of the bipolar plate is increased, it can easily act on the discharge of water during fuel cell operation.

Experimental Example 4

The CV and corrosion tests of the Pb bipolar plate obtained in Example 1 and the Ag-Pb bipolar plate obtained in Example 2 were analyzed as follows using a Bio-logic Science instrument, and the results are shown in FIGS. 6a to 6c it was The performance of the electrochemical system composed of three electrodes as counter, reference and working electrodes: Pt wire, Hg/Hg ₂ SO ₄ and Pb bipolar plate or Ag-Pb bipolar plate was respectively analyzed. The CV of each bipolar plate with an active surface area of 1 cm 2 was measured at a scan rate of 5 mV/s in 0.5 MH ₂ SO ₄ solutions of 0 to -1.2 V and 0 to 1.2 V. Corrosion was analyzed in a 0.5 M H2SO4 solution with a HF concentration of 3 ppm at a scan rate of 2 mV/s under URFC operating conditions.

The CV performance of the Pb bipolar plate and the Ag-Pb bipolar plate is as shown in Figs. 6a and 6b. As shown in Fig. 6a, a strong redox reaction was observed in the Pb bipolar plate, thus confirming the possibility of an efficient electrochemical reaction. The oxidation and reduction peaks of Pb such as oxidation (Pb to PbSO ₄ ) and reduction (PbSO ₄ to Pb) in the Pb bipolar plate were much lower in the Ag-Pb bipolar plate than in the Pb bipolar plate due to the presence of Ag.

In order to further understand the electrochemical stability performance of the bipolar plate material, a corrosion test was performed, and Fig. 6c compares the corrosion test results of the Pb bipolar plate and the Ag-Pb bipolar plate. The corrosion resistance of the Pb bipolar plate was reduced compared to that of the Ag-Pb bipolar plate, and the corrosion of the Ag-Pb bipolar plate coated with Ag on the surface of the Pb bipolar plate was significantly reduced. This shows that the metal coating layer formed on the surface of the Pb bipolar plate can improve the corrosion resistance of the Pb bipolar plate, thereby improving the overall stability of the bipolar plate.

Experimental Example 5

In order to compare and analyze the corrosion properties of the Pb bipolar plate obtained in Example 1 and the carbon material bipolar plate, a corrosion test was performed as follows. The corrosion test was performed at -1.5V to 2.0V using the same method as in Experimental Example 4 using three electrodes, and the electrolyte was tested and evaluated in 0.5M H ₂ SO ₄ .

As a result of the evaluation, the corrosion current density (I _corr ) of the carbon bipolar plate was 3.22 μA/cm ² , but the Pb bipolar plate (metal plate) had a low corrosion current density of 0.202 μA/cm ² .

Therefore, the Pb bipolar plate according to the present invention also has slightly lower performance than the Ag-Pb bipolar plate, but it seems to be suitable as a URFC bipolar plate. (DOE target; 1.00 μA/cm ² or less)

Although the present invention has been illustrated and described with reference to preferred embodiments as described above, it is not limited to the above-described embodiments, and those of ordinary skill in the art to which the present invention pertains within the scope not departing from the spirit of the present invention Various changes and modifications will be possible.

100: Pb bipolar plate / Ag-Pb bipolar plate
110: lead metal plate 120: euro
130: metal coating layer

Claims (15)

metal plate made of lead; a flow path formed on at least one surface of the metal plate; and a metal coating layer formed on the surface of the metal plate on which the flow path is formed.
The metal plate is a Pb metal sheet,
The flow path is formed to have a depth of 1/4 or more and 2/3 or less of the thickness of the metal plate,
The water contact angle of the metal coating layer is 90° or more,
As the thickness of the metal coating layer increases, the water contact angle increases.
delete The method of claim 1,
The metal coating layer is any one selected from the group consisting of Ag, Pt, Au, Ni, Cr, Sn, or a bipolar plate characterized in that it is formed including at least one of oxides, carbides, and nitrides of these metals.
delete delete delete delete delete delete delete delete An integrated reversible fuel cell comprising the bipolar plate of claim 1 or 3. delete A secondary battery comprising the bipolar plate of claim 1 or 3 as a current collector.
15. The method of claim 14,
The secondary battery is a secondary battery, characterized in that the redox flow battery.

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