WO2016060045A1 - 炭素シート、ガス拡散電極基材、および燃料電池 - Google Patents
炭素シート、ガス拡散電極基材、および燃料電池 Download PDFInfo
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- WO2016060045A1 WO2016060045A1 PCT/JP2015/078494 JP2015078494W WO2016060045A1 WO 2016060045 A1 WO2016060045 A1 WO 2016060045A1 JP 2015078494 W JP2015078494 W JP 2015078494W WO 2016060045 A1 WO2016060045 A1 WO 2016060045A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8605—Porous electrodes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/42—Platinum
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8663—Selection of inactive substances as ingredients for catalytic active masses, e.g. binders, fillers
- H01M4/8668—Binders
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/88—Processes of manufacture
- H01M4/8803—Supports for the deposition of the catalytic active composition
- H01M4/8807—Gas diffusion layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/88—Processes of manufacture
- H01M4/8817—Treatment of supports before application of the catalytic active composition
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/96—Carbon-based electrodes
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/023—Porous and characterised by the material
- H01M8/0234—Carbonaceous material
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/023—Porous and characterised by the material
- H01M8/0241—Composites
- H01M8/0243—Composites in the form of mixtures
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/023—Porous and characterised by the material
- H01M8/0241—Composites
- H01M8/0245—Composites in the form of layered or coated products
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/1007—Fuel cells with solid electrolytes with both reactants being gaseous or vaporised
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M2008/1095—Fuel cells with polymeric electrolytes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Definitions
- the present invention relates to a carbon sheet suitably used for a fuel cell, particularly a polymer electrolyte fuel cell, a gas diffusion electrode substrate including a microporous layer, and a fuel cell including the gas diffusion electrode substrate.
- a polymer electrolyte fuel cell that supplies a fuel gas containing hydrogen to the anode and an oxidizing gas containing oxygen to the cathode to obtain an electromotive force by an electrochemical reaction occurring at both electrodes is generally a separator, gas diffusion
- the electrode base material, the catalyst layer, the electrolyte membrane, the catalyst layer, the gas diffusion electrode base material, and the separator are laminated in this order.
- the above gas diffusion electrode base material has high gas diffusibility for diffusing the gas supplied from the separator to the catalyst layer, and high drainage for discharging water generated by the electrochemical reaction to the separator.
- high conductivity for taking out the generated current is necessary, and therefore, a gas diffusion electrode base material in which a microporous layer is formed on the surface of a carbon sheet made of carbon fiber or the like is widely used.
- the generated water can be quickly moved from the surface on which the catalyst layer of the gas diffusion electrode substrate is formed to the opposite surface by providing an inclination in water repellency. .
- flooding could not be sufficiently suppressed, and the power generation performance was still insufficient.
- An object of the present invention is to provide a carbon sheet that is excellent in flooding resistance, which has been difficult in the past, and that can be suitably used for a gas diffusion electrode substrate, in view of the background of the above-described conventional technology.
- Still another object of the present invention is to provide a gas diffusion electrode base material using the carbon sheet as a base material, and a fuel cell including the gas diffusion electrode base material.
- the present invention has the following configuration.
- a porous carbon sheet containing carbon fibers and a binder In the section from the surface having the 50% average fluorine intensity closest to one surface to the surface having the 50% average fluorine intensity closest to the other surface, the section is equally divided into three in the direction perpendicular to the plane of the carbon sheet. Of the layers close to one surface and the layers close to the other surface, the layer having a larger average fluorine intensity is defined as layer X, the smaller layer as layer Y, and between layer X and layer Y.
- a carbon sheet characterized in that, when the layer is a layer Z, the average fluorine intensity of the layer decreases in the order of the layer X, the layer Y, and the layer Z.
- the carbon sheet of the present invention can improve power generation performance particularly at a low temperature, and is suitably used for a gas diffusion electrode substrate.
- the carbon sheet of the present invention is a porous carbon sheet containing carbon fibers and a binder, and has a 50% average fluorine strength closest to one surface and a 50% average fluorine closest to the other surface.
- the layer obtained by equally dividing the section into three in the direction perpendicular to the surface of the carbon sheet the average of the layers among the layer close to one surface and the layer closest to the other surface
- the layer having higher fluorine strength is layer X
- the smaller layer is layer Y
- the layer between layer X and layer Y is layer Z
- the average fluorine strength of the layers is in the order of layer X, layer Y, layer Z. It is a carbon sheet characterized by becoming small.
- the 50% average fluorine intensity refers to a value of 50% of the average value of the fluorine intensity measured along a straight line in the direction perpendicular to the surface of the carbon sheet from one surface of the carbon sheet toward the other surface.
- the “surface having the 50% average fluorine intensity closest to one surface” means the point indicating the 50% average fluorine intensity closest to one surface on the straight line in the perpendicular direction of the carbon sheet in the above measurement. It represents an imaginary plane that includes a set and is substantially parallel to the surface of the carbon sheet, and does not need to be a continuous plane within the carbon sheet.
- the average fluorine intensity of layers decreases in the order of layer X, layer Y, and layer Z” means that the average fluorine intensity of each layer is in the relationship of layer X> layer Y> layer Z.
- FIG. 1 is a schematic cross-sectional view for illustrating and explaining a carbon sheet according to one embodiment of the present invention.
- the layer obtained by dividing the carbon sheet into three equal parts in the direction perpendicular to the surface is close to one surface (surface X (2))
- the layer having the highest average fluorine intensity of the layer is the layer X
- the layer close to the other surface (plane Y (3)) and having the average fluorine intensity of the layer smaller than the layer X is located between the layer Y and the layers X and Y.
- the carbon sheet (1) of the present invention is composed of the layer X (7), the layer Y (9), the layer Z (8), and the layer (4) less than 50% average fluorine intensity. .
- the carbon sheet of the present invention is produced by, for example, production of a porous body containing carbon fibers to be described later, impregnation with a resin composition, bonding and heat treatment performed as necessary, carbonization, and water repellent processing as necessary. can do.
- the carbon sheet of the present invention refers to a porous sheet containing carbon fibers and a binder, and can be water-repellent processed as necessary.
- the carbon sheet of the present invention is porous. Since the carbon sheet is porous, both excellent gas diffusibility and drainage can be achieved. In order to make the carbon sheet porous, it is preferable to use a porous body as a material used for producing the carbon sheet.
- the carbon sheet of the present invention preferably has high conductivity for taking out the generated current in addition to the above-described excellent gas diffusibility and drainage.
- a porous body having conductivity as a material used for producing the carbon sheet.
- a porous body containing carbon fibers such as carbon fiber woven fabric, carbon paper and carbon fiber nonwoven fabric, and a carbonaceous foamed porous body.
- a porous body containing carbon fiber since it is excellent in corrosion resistance, it is a more preferable embodiment to use a porous body containing carbon fiber, which has excellent characteristics to absorb dimensional change in the perpendicular direction of the electrolyte membrane, that is, “spring property”. Therefore, it is a more preferable embodiment to use a carbon paper obtained by bonding a carbon fiber papermaking body with a carbide (binder).
- the generated water generated by power generation moves quickly from the layer X to the layer Z.
- the average fluorine intensity of the layer Y is larger than the layer Z, the generated water is less likely to accumulate in the portion of the layer Y in contact with the separator rib portion, and flooding is suppressed.
- the average fluorine intensity of the layer X of the carbon sheet of the present invention is preferably 1.30 to 9.00, and preferably 1.40 to 8.00, where the average fluorine intensity of the layer Y is 1. Is more preferable, and is more preferably 1.50 to 7.00.
- the average fluorine intensity of the layer X with respect to the average fluorine intensity of the layer Y is 1.30 or more, more preferably 1.40 or more, and still more preferably 1.50 or more, the generated water is transferred from the layer X side to the layer Y side. It becomes easy to be discharged.
- the average fluorine intensity of the layer Y is 1, the average fluorine intensity of the layer X is 9.00 or less, more preferably 8.00 or less, and still more preferably 7.00 or less.
- the average fluorine intensity of layer Y increases.
- the layer Y since the layer Y is considered to have an average fluorine strength of a certain level or more, it has a water repellency of a certain level or more. As a result, the generated water is less likely to accumulate in the portion of the layer Y that contacts the separator rib portion, and flooding is suppressed.
- the average fluorine intensity of the layer Z of the carbon sheet of the present invention is preferably 0.10 to 0.90, preferably 0.30 to 0.80, where the average fluorine intensity of the layer Y is 1. Is more preferably 0.50 to 0.70.
- the average fluorine intensity of the layer Y is 1, the average fluorine intensity of the layer Z is 0.90 or less, more preferably 0.80 or less, and still more preferably 0.70 or less. Therefore, the ratio of the average fluorine intensity of the layer Z to the layer X can be reduced. As a result, the difference in the average fluorine intensity between the layer X and the layer Z increases, so that the generated water generated by power generation easily moves from the layer X to the layer Z quickly.
- the drainage speed of the generated water from the layer X is remarkably improved, and the power generation performance is easily improved.
- the average fluorine intensity of the layer Z with respect to the average fluorine intensity of the layer Y is 0.10 or more, more preferably 0.30 or more, and further preferably 0.50 or more, the water repellency of the layer Z is relatively improved. Since it increases, the generated water is less likely to accumulate in the layer Z, and flooding is suppressed.
- the thickness of the carbon sheet of the present invention is preferably 50 to 230 ⁇ m, more preferably 70 to 180 ⁇ m, and further preferably 90 to 130 ⁇ m.
- the thickness of the carbon sheet is 230 ⁇ m or less, more preferably 180 ⁇ m or less, and even more preferably 130 ⁇ m or less, the gas diffusibility is likely to increase, and the generated water is also easily discharged. Further, the size of the fuel cell as a whole can be easily reduced.
- the thickness of the carbon sheet is 50 ⁇ m or more, more preferably 70 ⁇ m or more, and even more preferably 90 ⁇ m or more, gas diffusion in the in-plane direction inside the carbon sheet is efficiently performed, and power generation performance is easily improved. .
- the thickness of the carbon sheet of the present invention is obtained by the following method. That is, the difference between the height when the measured object is present and absent when the pressure sheet is applied with a pressure of 0.15 MPa is measured by placing the carbon sheet and the gas diffusion electrode substrate on a smooth surface plate. Sampling is performed at 10 different locations, and the average of the measured height differences is taken as the thickness.
- the density of the carbon sheet is preferably in the range of 0.20 to 0.40 g / cm 3 , more preferably in the range of 0.22 to 0.35 g / cm 3 , and More preferably, it is within the range of 24 to 0.30 g / cm 3 .
- the density is 0.20 g / cm 3 or more, more preferably 0.22 g / cm 3 or more, and still more preferably 0.24 g / cm 3 or more, the mechanical properties of the carbon sheet are improved, and the electrolyte membrane and the catalyst layer are formed. It becomes easier to support. In addition, the electrical conductivity is high and the power generation performance is easily improved.
- the density is 0.40 g / cm 3 or less, more preferably 0.35 g / cm 3 or less, and further preferably 0.30 g / cm 3 or less, drainage is improved and flooding is easily suppressed.
- the carbon sheet having such a density is obtained by controlling the basis weight of the carbon fiber, the amount of the resin component attached to the carbon fiber, and the thickness of the carbon sheet, as will be described later in the carbon sheet manufacturing method.
- the density of the carbon sheet is obtained by dividing the basis weight (mass per unit area) of the carbon sheet weighed using an electronic balance by the thickness of the carbon sheet when pressed with a surface pressure of 0.15 MPa. be able to.
- the binder represents a component other than carbon fibers in the carbon sheet.
- the binder includes a resin composition that is a material for bonding carbon fibers to each other or a carbide thereof. Further, when a water repellent material is used for the carbon sheet of the present invention, the water repellent material is included in the binder.
- the “resin composition” may represent the resin composition, the resin composition and its carbide, and may represent the resin composition carbide.
- carbonized_material of a resin composition is what the resin component in a resin composition carbonized.
- the carbon sheet of the present invention in which the average fluorine intensity of the layers is made smaller in the order of layer X, layer Y, and layer Z controls the fiber diameter and density of the carbon fibers constituting the carbon sheet and the distribution of the binder in the perpendicular direction. However, it is more preferable to control the distribution of the binder.
- the amount of impregnation of the resin composition in the pre-impregnated body obtained by impregnating the resin composition into a porous body such as a carbon fiber paper body produced by the method described later Three pre-impregnated bodies of different sizes are prepared, and these are obtained by laminating and carbonizing them, and the amount of the resin composition attached when impregnating the resin composition into a porous body such as a carbon fiber papermaking body.
- a pre-impregnated body having a different thickness is laminated, a rapid change in fluorine strength occurs at the lamination interface, and the produced water may not be smoothly discharged and may easily stay at the interface, so a sudden change does not occur.
- Made from one pre-impregnated body It is preferable. Also, rather than laminating a plurality of pre-impregnated bodies, it is easy to reduce the thickness of the carbon sheet to be produced, so that the thickness is within the above preferred range. It is also suitable for the purpose.
- the sum of the volumes of pores having a diameter in the range of 1 to 100 ⁇ m is 100%
- the sum of the volumes of pores having a diameter in the range of 50 to 100 ⁇ m is 17 to 50%. If it exists, since drainage property improves especially and shows high flooding resistance, it is preferable.
- the pores having a diameter in the range of 50 to 100 ⁇ m have an important role in controlling water and water vapor during power generation. The proportion of large pores in this range is also related to the uniformity of the carbon sheet such as uneven formation. If the sum of the volume of pores having a diameter in the range of 1 to 100 ⁇ m is 100%, the drainage performance is improved if the sum of the volumes of pores having a diameter in the range of 50 to 100 ⁇ m is 17% or more. And flooding can be suppressed. Moreover, if it is 50% or less, since the carbon sheet which consists of papermaking etc. can produce uniformly, without formation unevenness etc., mechanical characteristics, such as tensile strength, can be improved.
- the pore diameter peak having a diameter in the range of 1 to 100 ⁇ m is preferably in the range of 30 to 50 ⁇ m, and more preferably in the range of 35 to 45 ⁇ m.
- the peak of the diameter of the pore having a diameter in the range of 1 to 100 ⁇ m is in the range of 30 to 50 ⁇ m, it is possible to more effectively suppress flooding and improve mechanical properties.
- porous body used for producing a porous carbon sheet will be described.
- the porous carbon sheet of the present invention has a high gas diffusibility for diffusing the gas supplied from the separator to the catalyst layer, and a high drainage property for discharging water generated by the electrochemical reaction to the separator. And high conductivity for taking out the generated current.
- the porous body used to obtain the porous carbon sheet is preferably a porous body containing carbon fibers such as a carbon fiber papermaking body, a carbon fiber woven fabric, and a felt type carbon fiber nonwoven fabric. It is an aspect.
- the carbon fiber papermaking body should be used as the porous body because of its excellent property of absorbing the dimensional change of the electrolyte membrane in the direction perpendicular to the surface, that is, "spring property". Is preferred.
- a carbon fiber papermaking body will be described as a representative example.
- Examples of the carbon sheet of the present invention and the carbon fiber in the porous body used to obtain the carbon sheet include polyacrylonitrile (PAN) -based, pitch-based and rayon-based carbon fibers.
- PAN polyacrylonitrile
- PAN-based carbon fibers and pitch-based carbon fibers are preferably used because of their excellent mechanical strength.
- the carbon fiber of the present invention and the carbon fiber in the porous body used to obtain the carbon sheet preferably have an average diameter of single fibers (hereinafter referred to as carbon fiber diameter) in the range of 3 to 20 ⁇ m, preferably 5 to 10 ⁇ m. More preferably within the range.
- carbon fiber diameter is 3 ⁇ m or more, more preferably 5 ⁇ m or more, the diameter of the pores becomes large, drainage performance is improved, and flooding is easily suppressed.
- the carbon fiber diameter is 20 ⁇ m or less, more preferably 10 ⁇ m or less, the thickness unevenness is reduced, and it becomes easy to control the thickness range of a preferable carbon sheet described later.
- the carbon fiber diameter is taken with a microscope such as a scanning electron microscope, and the carbon fiber is magnified 1000 times to take a photograph, randomly select 30 different single fibers, measure the diameter, The average value is obtained.
- a microscope such as a scanning electron microscope
- S-4800 manufactured by Hitachi, Ltd. or its equivalent can be used as the scanning electron microscope.
- the average length of single fibers (hereinafter referred to as carbon fiber length) is preferably in the range of 3 to 20 mm, and more preferably in the range of 5 to 15 mm.
- the carbon fiber length is 3 mm or more, more preferably 5 mm or more, the carbon sheet tends to be excellent in mechanical strength, electrical conductivity and thermal conductivity.
- the carbon fiber length is 20 mm or less, more preferably 15 mm or less, the carbon fiber is excellent in dispersibility during papermaking, and a homogeneous carbon sheet is easily obtained.
- Carbon fibers having such a carbon fiber length can be obtained by a method of cutting continuous carbon fibers into a desired length.
- the average length (carbon fiber length) of carbon fiber single fiber is 50 times larger, and the photo is taken with a microscope such as a scanning electron microscope, and 30 different single fibers are selected at random. The length is measured and the average value is obtained.
- a scanning electron microscope Hitachi, Ltd. S-4800 or an equivalent thereof can be used.
- the carbon fiber diameter and the carbon fiber length are usually measured by directly observing the carbon fiber as the raw material, but can also be measured by observing the carbon sheet.
- a carbon fiber papermaking body formed by papermaking which is one form of a porous body used to obtain a carbon sheet, is intended to keep the in-plane conductivity and thermal conductivity isotropic when made into a carbon sheet.
- the carbon fiber is preferably in the form of a sheet in which it is randomly dispersed in a two-dimensional plane.
- the carbon fiber papermaking for obtaining the carbon fiber papermaking body can be performed only once or can be performed by laminating a plurality of times.
- the carbon fiber papermaking body preferably has a carbon fiber basis weight in the range of 10 to 50 g / m 2 , more preferably in the range of 15 to 35 g / m 2 , and 20 to 30 g / m 2. and even more preferably within the range of m 2.
- the carbon fiber basis weight in the carbon fiber papermaking body is 10 g / m 2 or more, more preferably 15 g / m 2 or more, and further preferably 20 g / m 2 or more
- the carbon sheet obtained from the carbon fiber papermaking body has a mechanical strength. It tends to be an excellent one.
- the basis weight of the carbon fiber in the carbon fiber paper body is 50 g / m 2 or less, more preferably 35 g / m 2 or less, and further preferably 30 g / m 2 or less, a carbon sheet obtained from the carbon fiber paper body is obtained. It tends to be excellent in in-plane gas diffusion and drainage.
- the basis weight of the carbon fibers of the carbon fiber papermaking body after pasting is preferably in the range of 10 to 50 g / m 2 .
- the basis weight of the carbon fiber in the carbon sheet is a residue of the carbon fiber paper body cut out in 10 cm square in a nitrogen atmosphere in an electric furnace at a temperature of 450 ° C. for 15 minutes to remove organic matter. It can be determined by dividing the mass by the area of the carbon fiber papermaking body (0.01 m 2 ).
- a porous body containing carbon fibers such as a carbon fiber papermaking body is impregnated with a resin composition serving as a binder.
- the binder in the carbon sheet refers to a component other than the carbon fibers in the carbon sheet, and mainly serves to bind the carbon fibers together.
- the material that plays a role in binding carbon fibers include a resin composition impregnated in a porous body or a carbide thereof.
- a porous body containing carbon fibers impregnated with a resin composition serving as a binder may be referred to as a “pre-impregnated body”.
- a method of impregnating a porous body containing carbon fibers with a resin composition as a binder a method of immersing the porous body in a resin composition to which a solvent is added, or a resin composition to which a solvent is added is applied to the porous body. And a method of transferring the layer in a film having a layer made of a resin composition to a porous body. Especially, since productivity is excellent, the method of immersing a porous body in the resin composition which added the solvent is used especially preferable.
- the carbon sheet of the present invention is characterized in that the average fluorine intensity of the layers decreases in the order of layer X, layer Y, and layer Z.
- the method for adjusting the average fluorine intensity of each layer is not particularly limited, but water repellent finishing described later is preferably used.
- the water-repellent material When performing water-repellent processing using a water-repellent material containing fluorine atoms, the water-repellent material tends to adhere more to the surface of the binding material than the carbon fiber surface, particularly the surface of the binding material carbonized with the resin component. There is. Therefore, in the carbon sheet in which the average fluorine intensity decreases in the order of the layer X, the layer Y, and the layer Z, the amount of the resin composition of the layer X, the layer Y, and the layer Z when the resin composition is impregnated into the porous body. It can obtain by making it small in order.
- a carbon fiber papermaking body is impregnated with the resin composition as a binder uniformly throughout the entire surface to obtain a pre-impregnated body, and then excess from one side before drying.
- a method of controlling and distributing the amount of the resin composition in the direction perpendicular to the surface of the carbon sheet or its carbide by removing the resin composition adhering to the surface is conceivable.
- the following method may be mentioned. After immersing the carbon fiber paper body in a solution containing the resin composition to obtain a pre-impregnated body, before the drying, the solution containing the resin composition is sucked from one surface, or the carbon fiber paper body By pressing the squeeze roll only on one surface, the adhesion amount in the vicinity of the surface Y can be reduced with respect to the adhesion amount in the vicinity of the surface X. On the other hand, since the solvent volatilizes from the surface in the drying process, the resin composition can be distributed more on the surface than in the pre-impregnated body.
- the amount of the resin composition serving as the binder can be changed so as to decrease in the order of layer X, layer Y, and layer Z, and this is averaged by carbonizing and water repellent processing.
- the fluorine intensity can be controlled to decrease in the order of layer X, layer Y, and layer Z.
- a carbon fiber papermaking body is immersed in a solution containing the resin composition to obtain a pre-impregnated body, and then the carbon
- the resin composition is additionally applied to only one surface of the fiber paper body by spraying or gravure roll, and carbonization and water repellent processing are performed, so that the average fluorine strength is in the order of the carbon sheet layers X, Y, and Z.
- a method for controlling to be small can be mentioned.
- the resin composition used in preparing the pre-impregnated body is obtained by adding a solvent or the like to the resin component as necessary.
- the resin component includes a resin such as a thermosetting resin or a thermoplastic resin, and further includes an additive such as a carbon powder or a surfactant as necessary.
- the carbonization yield of the resin component contained in the resin composition is preferably 40% by mass or more.
- the carbonization yield is 40% by mass or more, the carbon sheet tends to be excellent in mechanical properties, electrical conductivity, and thermal conductivity.
- the carbonization yield of the resin component contained in a resin composition it is about 60 mass% normally.
- thermosetting resins such as phenol resin, epoxy resin, melamine resin, and furan resin.
- a phenol resin is preferably used because of high carbonization yield.
- carbon powder can be used for the purpose of improving the mechanical properties, conductivity and thermal conductivity of the carbon sheet.
- carbon powder carbon black such as furnace black, acetylene black, lamp black and thermal black
- graphite such as scaly graphite, scaly graphite, earthy graphite, artificial graphite, expanded graphite and flake graphite, carbon nanotube, Carbon nanofibers, carbon fiber milled fibers, and the like can be used.
- the resin composition can use the above-described resin components as they are, and can contain various solvents as necessary for the purpose of improving the impregnation property into a porous body such as a carbon fiber papermaking body.
- methanol, ethanol, isopropyl alcohol, or the like can be used as the solvent.
- the resin composition is preferably in a liquid state at 25 ° C. and 0.1 MPa.
- the resin composition is liquid, the impregnation property into a porous body such as a carbon fiber papermaking body is excellent, and the resulting carbon sheet is excellent in mechanical properties, electrical conductivity, and thermal conductivity.
- the resin composition When impregnated, the resin composition is preferably impregnated so that the resin component is 30 to 400 parts by mass with respect to 100 parts by mass of the carbon fibers in the pre-impregnated body, and is 50 to 300 parts by mass. It is more preferable to impregnate.
- the carbon sheet has excellent mechanical properties, electrical conductivity and thermal conductivity when the impregnation amount of the resin component is 30 parts by mass or more, more preferably 50 parts by mass or more with respect to 100 parts by mass of the carbon fibers in the pre-impregnated body. It becomes.
- the impregnation amount of the resin component with respect to 100 parts by mass of the carbon fiber in the pre-impregnated body is 400 parts by mass or less, more preferably 300 parts by mass or less, the carbon sheet has excellent gas diffusibility.
- ⁇ Lamination and heat treatment> In the present invention, after forming a pre-impregnated body impregnated with a resin composition in a porous body such as a carbon fiber paper body, prior to carbonization, the pre-impregnated body is bonded or heat-treated on the pre-impregnated body. Can be.
- a plurality of pre-impregnated bodies can be bonded together for the purpose of making the carbon sheet have a predetermined thickness.
- a plurality of pre-impregnated bodies having the same properties can be bonded together, or a plurality of pre-impregnated bodies having different properties can be bonded together.
- a plurality of pre-impregnated bodies having different carbon fiber diameters, carbon fiber lengths, the weight of carbon fibers of a porous body such as a carbon fiber papermaking body used for obtaining a pre-impregnated body, and the amount of resin component impregnated are different. It can also be pasted together.
- discontinuous surfaces are formed in the direction perpendicular to the surface by laminating, and the drainage performance may be reduced. Therefore, in the present invention, a single sheet without bonding a porous body such as a carbon fiber papermaking body. It is preferable to use it only, and heat-treat it.
- the pre-impregnated body can be heat-treated for the purpose of thickening and curing the resin composition in the pre-impregnated body.
- a heat treatment method a method of blowing hot air, a method of heating by sandwiching between hot plates such as a press device, a method of heating by sandwiching between continuous belts, or the like can be used.
- a porous material such as a carbon fiber papermaking body is impregnated with a resin composition to obtain a pre-impregnated material, and then fired in an inert atmosphere in order to carbonize the resin component.
- a batch type heating furnace can be used, or a continuous type heating furnace can be used.
- the inert atmosphere can be obtained by flowing an inert gas such as nitrogen gas or argon gas in the furnace.
- the maximum temperature for firing is preferably in the range of 1300 to 3000 ° C, more preferably in the range of 1700 to 3000 ° C, and still more preferably in the range of 1900 to 3000 ° C.
- the maximum temperature is 1300 ° C. or higher, the carbonization of the resin component in the pre-impregnated body proceeds, and the carbon sheet has excellent conductivity and thermal conductivity.
- the maximum temperature is 3000 ° C. or lower, the operating cost of the heating furnace is lowered.
- Water repellent finish> it is preferable to subject the carbon fiber fired body to water repellent treatment for the purpose of improving drainage.
- the water repellent finish can be performed, for example, by applying a water repellent material to the carbon fiber fired body and heat-treating it.
- the water-repellent material is included in the carbon sheet as a binder.
- the sliding angle of water on the surface Y is preferably 40 degrees or less.
- the gas diffusion electrode substrate of the present invention can be obtained.
- the surface Y side is the separator side.
- the sliding angle of the surface Y As a method of controlling the sliding angle of the surface Y to 40 degrees or less, there is a method of melting the water repellent material to lower the viscosity during the heat treatment in the water repellent processing step.
- the water repellent material By melting the water repellent material, the water repellent material spreads uniformly on the surface of the carbon fiber in the carbon sheet, the water sliding angle can be made 40 degrees or less, and the flooding resistance can be improved.
- the sliding angle of water on the surface Y means a sliding angle obtained by measurement from the surface Y side of the carbon sheet.
- the melting point of the water-repellent material used in the water-repellent processing is preferably in the range of 200 to 320 ° C, more preferably in the range of 230 to 310 ° C, and in the range of 250 to 300 ° C. Is more preferable.
- the water repellent material has a melting point of 320 ° C. or lower, more preferably 310 ° C. or lower, and even more preferably 300 ° C. or lower, the water repellent material is easily melted during heat treatment in the water repellent processing step.
- the carbon sheet spreads uniformly on the carbon fiber surface in the carbon sheet, and a carbon sheet with high water repellency can be obtained, and the flooding resistance can be improved.
- the water repellent material has a melting point of 200 ° C. or higher, more preferably 230 ° C. or higher, and even more preferably 250 ° C. or higher, the water repellent material is less likely to be thermally decomposed during heat treatment in the water repellent processing step. It is possible to obtain a carbon sheet having a high aqueous property, and to improve the flooding resistance.
- fluorine-based polymer As the type of water repellent material used in the water repellent processing, it is preferable to use a fluorine-based polymer because of its excellent corrosion resistance.
- fluorine-based polymer include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP) and / or tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA).
- PTFE polytetrafluoroethylene
- FEP tetrafluoroethylene-hexafluoropropylene copolymer
- PFA tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer
- the water-repellent material By using tetrafluoroethylene-hexafluoropropylene copolymer (FEP) and / or tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) as the water-repellent material used in water-repellent processing, the water-repellent material is melted.
- the water repellent material spreads uniformly on the carbon fiber surface in the carbon sheet, and a carbon sheet with high water repellency can be obtained.
- the water repellent material spreads uniformly on the surface of the carbon fiber in the carbon sheet, the water repellent material on the surface of the carbon fiber becomes thin, so that the contact resistance between the separator and the carbon sheet is preferably reduced.
- the sliding angle of water on the surface Y can be made 40 degrees or less, so that the drainage of the carbon sheet can be greatly increased, and the water repellent treated carbon Since the accumulation of water inside the sheet can be reduced, the gas diffusibility can also be greatly improved. For this reason, it leads to a significant improvement in power generation performance.
- the amount of the water-repellent material attached during the water-repellent processing is preferably 1 to 50 parts by mass and more preferably 2 to 40 parts by mass with respect to 100 parts by mass of the carbon fiber fired body.
- a carbon sheet will become the thing excellent in drainage as the adhesion amount of a water repellent material is 1 mass part or more with respect to 100 mass parts of carbon fiber sintered bodies, More preferably, it is 2 mass parts or more.
- the amount of the water repellent material attached is 50 parts by mass or less, more preferably 40 parts by mass or less with respect to 100 parts by mass of the carbon fiber fired body, the carbon sheet has excellent conductivity.
- the fluorine strength of the carbon sheet is determined as follows.
- a description will be given with reference to FIG.
- the carbon sheet (1) in the direction perpendicular to the surface is randomly selected by a sharp blade.
- 50 cross-section observation samples are prepared.
- SEM scanning electron microscope
- EDX -energy dispersive X-ray analysis
- a line scan is performed on the cross section of the 50 carbon sheets (1) in the direction perpendicular to the surface of the carbon sheet (1).
- the distribution (11) of the fluorine intensity (fluorine signal intensity) is obtained.
- the fluorine intensity is measured under the conditions of an acceleration voltage of 7 kV, an enlargement magnification of 300 times, and a line width of 20 ⁇ m.
- a value (13) that is 50% of the average value (12) of the fluorine intensity measured along a straight line in the direction perpendicular to the surface of the carbon sheet from one surface of the carbon sheet (1) to the other surface is provisionally determined.
- the layer including the surface XX (5) is provisionally determined as the layer X (7)
- the surface YY is provisionally determined as layer Y (9)
- the center layer sandwiched between layers X (7) and Y (9) is defined as layer Z (8).
- the average value of the fluorine intensity in each layer X of the 50 carbon sheets is calculated, and 50 “average values of the fluorine intensity in the layer X” are obtained.
- the average value of the 50 obtained “average value of fluorine intensity in layer X” is defined as the average fluorine intensity of layer X.
- the average fluorine intensity is calculated in the same manner.
- the layer having the higher average fluorine intensity is the layer X
- the smaller layer is the layer Y
- the surface on the layer X side of the carbon sheet is the surface X
- the surface on the layer Y side is the surface Y.
- the carbon fiber fired body corresponds to a “carbon sheet”. As described above, the carbon fiber fired body is subjected to water-repellent processing as necessary. In the present invention, the carbon fiber fired body subjected to water-repellent processing also corresponds to the “carbon sheet”. The carbon fiber fired body which is not subjected to water repellent treatment naturally corresponds to a “carbon sheet”.
- the gas diffusion electrode substrate of the present invention can be produced by forming a microporous layer described later on the above-described carbon sheet.
- the carbon sheet of the present invention can be used as a gas diffusion electrode substrate by forming a microporous layer on one surface.
- the gas diffusion electrode substrate of the present invention preferably has a microporous layer on the surface X side of the carbon sheet.
- the filler-containing coating liquid is less likely to penetrate into the carbon sheet, and the microporous layer is formed on the surface of the carbon sheet with a more preferable thickness, drying of the electrolyte membrane is further suppressed by the reverse diffusion of generated water. .
- Basis weight of the microporous layer is not particularly limited, but is preferably in the range of 10 ⁇ 35g / m 2, more preferably 14 ⁇ 30g / m 2, more preferably 16 ⁇ 25g / m 2.
- the basis weight of the microporous layer is 10 g / m 2 or more, more preferably 14 g / m 2 or more, and further preferably 16 g / m 2 or more, one surface of the carbon sheet can be covered with the microporous layer, Back diffusion of water is further promoted, and drying of the electrolyte membrane can be further suppressed. Further, when the basis weight of the microporous layer is 35 g / m 2 or less, more preferably 30 g / m 2 or less, and even more preferably 25 g / m 2 or less, drainage performance is further improved and flooding can be further suppressed. .
- the microporous layer preferably contains a filler.
- carbon powder is preferable.
- Carbon powders include carbon black such as furnace black, acetylene black, lamp black and thermal black, graphite such as scaly graphite, scaly graphite, earthy graphite, artificial graphite, expanded graphite, and flake graphite, carbon nanotube, carbon nano Examples thereof include fiber and carbon fiber milled fiber.
- carbon black is more preferably used as the filler carbon powder, and acetylene black is most preferably used because it has few impurities.
- a porous body containing linear carbon and a water repellent material can be used for the microporous layer from the viewpoint of improving conductivity and drainage.
- the microporous layer contains carbon powder, the carbon powder is linear carbon, and the aspect ratio of the linear carbon is 30 to 5000, whereby the filler-containing coating that is a precursor of the microporous layer is used. Since the penetration of the liquid into the carbon sheet can be moderately suppressed and the gas diffusibility and drainage in the in-plane direction can be improved, flooding can be suppressed, and furthermore, the carbon sheet surface layer has a sufficient thickness. Since the microporous layer having a thickness is formed and the back diffusion of the generated water is promoted, drying of the electrolyte membrane can be suppressed.
- the microporous layer preferably includes a water repellent material.
- a fluorine-type polymer as a water repellent material.
- the fluorine-based polymer include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA).
- the filler-containing coating liquid may contain a dispersion medium such as water or an organic solvent, or may contain a dispersion aid such as a surfactant.
- a dispersion medium water is preferable, and a nonionic surfactant is preferably used as a dispersion aid.
- fillers and water repellent materials such as various carbon powders as described above can also be contained.
- the microporous layer can be formed by applying a coating liquid containing the above-mentioned filler (filler-containing coating liquid) to one side of the carbon sheet, preferably the surface X side of the carbon sheet.
- a coating liquid containing the above-mentioned filler filler-containing coating liquid
- the microporous layer having a pore size smaller than that of the carbon sheet inhibits drainage and gas diffusion from the gas diffusion electrode substrate to the separator. It is preferable to form a porous layer.
- the microporous layer is preferably formed by applying a coating liquid containing the filler (filler-containing coating liquid) a plurality of times.
- a coating liquid containing the filler (filler-containing coating liquid) By applying multiple times, the average fluorine intensity of layer X increases, and the difference in average fluorine intensity between layers X and Z increases, so the generated water generated by power generation moves quickly from layer X to layer Z. It becomes easy. As a result, the drainage speed of the generated water from the layer X is remarkably improved, and the power generation performance is easily improved.
- coating methods such as screen printing, rotary screen printing, spray spraying, intaglio printing, gravure printing, die coater coating, bar coating, and blade coating can be used.
- the coating methods exemplified above are merely examples, and are not necessarily limited thereto.
- the coated material is put into a drier set at a temperature of 80 to 180 ° C. and dried in a range of 5 to 30 minutes.
- the amount of drying air can be determined as appropriate, but rapid drying may induce surface microcracks.
- After drying the coated material it is put into a muffle furnace, a baking furnace or a high-temperature dryer, and preferably heated at a temperature of 300 to 380 ° C. for 5 to 20 minutes to melt the water repellent material, It is preferable to form a microporous layer as a binder between fillers.
- a membrane electrode assembly can be formed by bonding the gas diffusion electrode base material described above to at least one surface of a solid polymer electrolyte membrane having catalyst layers on both surfaces. At that time, by arranging the microporous layer of the gas diffusion electrode substrate on the catalyst layer side, the back diffusion of the generated water is more likely to occur, and the contact area between the catalyst layer and the gas diffusion electrode substrate is increased. The contact electrical resistance can be reduced.
- the fuel cell of the present invention includes the gas diffusion electrode base material of the present invention, that is, has a separator on both sides of the membrane electrode assembly described above. That is, a fuel cell is configured by arranging separators on both sides of the membrane electrode assembly.
- a polymer electrolyte fuel cell is constructed by laminating a plurality of such membrane electrode assemblies on both sides sandwiched by separators via gaskets.
- the catalyst layer is composed of a layer containing a solid polymer electrolyte and catalyst-supporting carbon. As the catalyst, platinum is usually used.
- a fuel cell in which a reformed gas containing carbon monoxide is supplied to the anode side it is preferable to use platinum and ruthenium as the catalyst on the anode side.
- the solid polymer electrolyte it is preferable to use a perfluorosulfonic acid polymer material having high proton conductivity, oxidation resistance, and heat resistance.
- a resin obtained by mixing a resol type phenol resin and a novolac type phenol resin at a mass ratio of 1: 1 as a thermosetting resin, scaly graphite (average particle size 5 ⁇ m) as a carbon powder, and methanol as a solvent, Thermosetting resin / carbon powder / solvent 10 parts by mass / 5 parts by mass / 85 parts by mass These are mixed and stirred for 1 minute using an ultrasonic dispersing device to uniformly disperse the resin composition.
- the carbon fiber paper body cut into 15 cm ⁇ 12.5 cm was immersed in a resin composition filled with aluminum bat and then squeezed by sandwiching it between two horizontally disposed rolls. At this time, the amount of the resin component attached to the carbon fiber papermaking body was adjusted by changing the clearance between two horizontally disposed rolls. Further, one of the two rolls was a smooth metal roll having a structure capable of removing excess resin with a doctor blade, and the other roll was a roll having a configuration of an uneven gravure roll.
- the pre-impregnated body was produced by heating and drying at a temperature of 100 ° C. for 5 minutes. Next, heat treatment was performed for 5 minutes at a temperature of 180 ° C. while pressing with a flat plate press. Spacers were arranged on the flat plate press during pressurization to adjust the distance between the upper and lower press face plates.
- the base material heat-treated with this pre-impregnated body was introduced into a heating furnace having a maximum temperature of 2400 ° C. maintained in a nitrogen gas atmosphere in a heating furnace, and a carbon sheet having a thickness of 220 ⁇ m made of a carbon fiber fired body was obtained. It was.
- ⁇ Water repellent finish> An aqueous dispersion of PTFE resin ("Polyflon” (registered trademark) PTFE Dispersion D-1E (manufactured by Daikin Industries, Ltd.)) or an FEP resin ("Neofluon”) is produced by using the carbon sheet prepared above as a water repellent material.
- the carbon fiber fired body was impregnated with a water-repellent material by immersing it in an aqueous dispersion of “(registered trademark) FEP dispersion ND-110 (manufactured by Daikin Industries, Ltd.). Thereafter, a dryer having a temperature of 100 ° C.
- the carbon sheet was heated and dried in a furnace for 5 minutes to produce a water-repellent carbon sheet, and when drying, the carbon sheet was placed vertically and the vertical direction was changed every minute.
- the aqueous dispersion of the water material was used after being diluted to an appropriate concentration so that 5 parts by mass of the water repellent material was applied to 95 parts by mass of the carbon sheet after drying.
- Carbon powder A Acetylene black “Denka Black” (registered trademark) (manufactured by Denki Kagaku Kogyo Co., Ltd.)
- Carbon powder B Linear carbon: Vapor growth carbon fiber “VGCF” (registered trademark) (manufactured by Showa Denko KK)
- Material C Water repellent material: PTFE resin (using “Polyflon” (registered trademark) PTFE dispersion D-1E (produced by Daikin Industries), which is an aqueous dispersion containing 60 parts by mass of PTFE resin)
- Material D Surfactant “TRITON” (registered trademark) X-100 (manufactured by Nacalai Tesque)
- This filler-containing coating solution is applied in a planar shape on one surface of a water-repellent carbon sheet using a slit die coater, and then heated at a temperature of 120 ° C. for 10 minutes and at a temperature of 380 ° C. for 10 minutes. did. In this way, a microporous layer was formed on the water-repellent carbon sheet to produce a gas diffusion electrode substrate.
- Carbon powder, water repellent material, surfactant and purified water are used for the filler-containing coating liquid used here, and the blending amount shown in the table is adjusted to be the composition of the filler-containing coating liquid described in parts by mass. What was done was used.
- the blending amount of the material C (PTFE resin) shown in the table represents the blending amount of the PTFE resin itself, not the blending amount of the aqueous PTFE resin dispersion.
- ⁇ Evaluation of power generation performance of polymer electrolyte fuel cells > 1.00 g of platinum-supported carbon (produced by Tanaka Kikinzoku Kogyo Co., Ltd., platinum support: 50% by mass), 1.00 g of purified water, “Nafion” (registered trademark) solution (“Nafion” (registered trademark) manufactured by Aldrich) 5.0 mass%) 8.00 g and isopropyl alcohol (manufactured by Nacalai Tesque) 18.00 g were sequentially added to prepare a catalyst solution.
- a catalyst solution was applied to 9001 (manufactured by Nichias Co., Ltd.) by spraying and dried at room temperature to prepare a PTFE sheet with a catalyst layer having a platinum amount of 0.3 mg / cm 2 .
- a solid polymer electrolyte membrane “Nafion” (registered trademark) NRE-211CS (manufactured by DuPont) cut to 8 cm ⁇ 8 cm is sandwiched between two PTFE sheets with a catalyst layer and pressed to 5 MPa with a flat plate press.
- the catalyst layer was transferred to a solid polymer electrolyte membrane by pressing at a temperature of 130 ° C. for 5 minutes. After pressing, the PTFE sheet was peeled off to produce a solid polymer electrolyte membrane with a catalyst layer.
- the solid polymer electrolyte membrane with a catalyst layer is sandwiched between two gas diffusion electrode substrates cut into 5 cm ⁇ 5 cm, pressed at a temperature of 130 ° C. for 5 minutes while being pressurized to 3 MPa with a flat plate press, and the membrane electrode A joined body was produced.
- the gas diffusion electrode substrate was arranged so that the surface having the microporous layer was in contact with the catalyst layer side.
- the obtained membrane electrode assembly was incorporated into a single cell for fuel cell evaluation, and the voltage when the current density was changed was measured.
- a serpentine type separator having a single flow path of 1.0 mm was used for the groove width, groove depth, and rib width. Further, evaluation was performed by supplying non-pressurized hydrogen to the anode side and non-pressurized air to the cathode side.
- both hydrogen and air were humidified using a humidification pot set at a temperature of 40 ° C.
- the humidity at this time was 100%.
- the utilization rates of hydrogen and oxygen in the air were 70 mol% and 40 mol%, respectively.
- An output voltage with a current density of 1.5 A / cm 2 was measured and used as an indicator of flooding resistance.
- the sliding angle of the water repellent carbon sheet was determined by a sliding method using an automatic contact angle meter.
- an automatic contact angle meter DM-501 manufactured by Kyowa Interface Science Co., Ltd. was used as an apparatus.
- the surface Y of the water-repellent carbon sheet is fixed on the apparatus stage with the upper side (measurement side), a droplet of 10 ⁇ L of ion-exchanged water is deposited on the surface Y of the carbon sheet, and after waiting for 1 second, the apparatus
- the carbon sheet that was water-repellent processed along with the stage was tilted, and the tilt angle of the apparatus stage when the liquid droplet began to slide down the carbon sheet surface was taken as the sliding angle.
- the melting point of the water repellent material was measured by differential scanning calorimetry. Using a DSC6220 manufactured by Seiko Instruments Inc. (SII), the apparatus was changed from 30 ° C. to 400 ° C. at a temperature rising rate of 2 ° C./min in nitrogen, and the endothermic peak at that time was observed. The endothermic peak at a temperature of 150 ° C. or higher was defined as the melting point of the water repellent material.
- the fluorine strength of the carbon sheet was determined as follows. Hereinafter, a description will be given with reference to FIG. First, after tentatively determining one surface of the carbon sheet (1) as the surface X (2) and the other surface as the surface Y (3), the carbon sheet (1) is sectioned in a perpendicular direction at random with a sharp blade. 50 observation samples were prepared. Using a scanning electron microscope (SEM) -energy dispersive X-ray analysis (EDX) apparatus, a line scan is performed on the cross section of the 50 carbon sheets (1) in the direction perpendicular to the surface of the carbon sheet (1). Then, distribution (11) of fluorine intensity (fluorine signal intensity) was obtained.
- SEM scanning electron microscope
- EDX energy dispersive X-ray analysis
- the fluorine intensity was measured under the conditions of an acceleration voltage of 7 kV, an enlargement magnification of 300 times, and a line width of 20 ⁇ m.
- a value (13) that is 50% of the average value (12) of the fluorine intensity measured along a straight line in the direction perpendicular to the surface of the carbon sheet from one surface of the carbon sheet (1) to the other surface is provisionally determined.
- the layer including the plane XX (5) is provisionally determined as the layer X (7)
- a layer including the surface YY (6) was provisionally determined as a layer Y (9)
- a central layer sandwiched between the layers X (7) and Y (9) was defined as a layer Z (8).
- the average value of fluorine intensity in layer X of each of the 50 carbon sheets was calculated to obtain 50 “average value of fluorine intensity in layer X”.
- the average value of the 50 obtained “average value of fluorine intensity in layer X” was defined as the average fluorine intensity of layer X.
- the average fluorine intensity was calculated in the same manner.
- the layer having the higher average fluorine intensity is the layer X
- the smaller layer is the layer Y
- the surface on the layer X side of the carbon sheet is the surface X
- the surface on the layer Y side is the surface Y. It was.
- the average fluorine intensity in the carbon sheet is not required because the carbon sheet alone cannot be obtained, the carbon sheet in the gas diffusion electrode base material, or the carbon sheet in the membrane electrode assembly
- the average fluorine intensity can be obtained by the above-described method using the cross-sectional observation sample.
- the above method takes an average of 50 samples prepared at random.
- the average fluorine intensity can be obtained because averaging is performed including continuous portions.
- Example 1 According to the methods described in ⁇ Preparation of Carbon Sheet>, ⁇ Water Repellent Processing>, and ⁇ Preparation of Gas Diffusion Electrode Base>, the average fluorine strength of the layers shown in Table 1 is layer X, layer Y, layer Z. The gas diffusion electrode base material using the porous carbon sheet which becomes small in order was obtained.
- Example 2 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1.
- Example 3 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1.
- Example 4 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1. At this time, by removing a large amount of the binder from the layer Y, the difference in the average fluorine intensity between the layer X and the layer Y was changed to be larger than that in Example 2.
- Example 5 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1. At this time, the total resin composition adhesion amount was changed to be larger than that in Example 2.
- Example 6 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1. At this time, the difference in the average fluorine intensity between the layer X and the layer Y was increased with respect to Example 5 by removing a large amount of the binder from the layer Y while increasing the total resin composition adhesion amount. .
- Example 7 With the configuration shown in Table 1, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1. At this time, the sliding angle of the surface Y was adjusted to 40 degrees or less by changing the type of water repellent material used for the water repellent processing of the carbon sheet to tetrafluoroethylene-hexafluoropropylene copolymer (FEP).
- FEP tetrafluoroethylene-hexafluoropropylene copolymer
- Example 8 With the configuration shown in Table 2, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1.
- Example 9 A polyacrylonitrile long fiber was subjected to a flameproofing treatment at a temperature of 200 ° C. for 10 minutes, a nonwoven fabric was produced by hydroentanglement treatment, and roll pressing was performed. Subsequently, it was introduced into a heating furnace having a temperature of 2000 ° C. and carbonized to obtain a carbon sheet made of a carbon fiber fired body of 150 ⁇ m thick nonwoven fabric. Next, as a water repellent material to be a binder, the PTFE resin used in the above ⁇ Water repellent processing> and the carbon powder A used in ⁇ Production of gas diffusion electrode base material> are in a mass ratio of solid content.
- aqueous dispersion of a water repellent material (the concentration of the aqueous water repellent material was 5% by mass of the water repellent material with respect to 95 parts by mass of the carbon sheet after drying). Adjusted to be granted).
- a carbon sheet made of a non-woven carbon fiber fired body is immersed in an aqueous dispersion of a water repellent material filled with an aluminum bat, and two rolls (two of the two) are arranged horizontally with a certain clearance.
- One roll is a smooth metal roll with a doctor blade, and the other roll is a gravure roll with irregularities), and the amount of water-repellent material attached to one surface of the carbon sheet differs from the other. It was.
- Example 10 With the configuration shown in Table 2, a carbon sheet and a gas diffusion electrode substrate were obtained in the same manner as in Example 1. At this time, by removing a small amount of the binder from the layer Y, the difference in the average fluorine intensity between the layer X and the layer Y was changed to be smaller than that in Example 2.
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Abstract
Description
一方の表面に最も近い50%平均フッ素強度を有する面から、他方の表面に最も近い50%平均フッ素強度を有する面までの区間において、前記区間を前記炭素シートの面直方向に3等分して得られる層について、一方の表面に近い層と他方の表面に近い層のうち、層の平均フッ素強度がより大きい層を層X、より小さい層を層Yとし、層Xと層Yの間の層を層Zとすると、層の平均フッ素強度が、層X、層Y、層Zの順に小さくなることを特徴とする、炭素シート。
本発明の炭素シートは、例えば、後述する炭素繊維を含む多孔体の作製、樹脂組成物の含浸、必要に応じて行われる貼り合わせと熱処理、炭化および必要に応じて撥水加工する工程により作製することができる。本発明の炭素シートは、炭素繊維および結着材を含む多孔質のものをいい、必要に応じて撥水加工することもできる。
多孔質の炭素シートを作製するために用いる多孔体について説明する。本発明の多孔質の炭素シートは、セパレータから供給されるガスを触媒層へと拡散するための高いガス拡散性と、電気化学反応に伴って生成する水をセパレータへ排出するための高い排水性、および発生した電流を取り出すための高い導電性を有することが好ましい。このため多孔質の炭素シートを得るためには、導電性を有する多孔体を用いることが好ましい。より具体的には、多孔質の炭素シートを得るために用いる多孔体は、例えば、炭素繊維抄紙体、炭素繊維織物およびフェルトタイプの炭素繊維不織布などの炭素繊維を含む多孔体を用いることが好ましい態様である。中でも、多孔体を多孔質の炭素シートとした際に、電解質膜の面直方向の寸法変化を吸収する特性、すなわち「ばね性」に優れていることから炭素繊維抄紙体を多孔体として用いることが好ましい。以下、炭素繊維抄紙体を代表例として説明する。
本発明の炭素シートを得る際においては、炭素繊維抄紙体などの炭素繊維を含む多孔体に、結着材となる樹脂組成物が含浸される。
予備含浸体を作製する際に用いる樹脂組成物は、樹脂成分に溶媒などを必要に応じて添加したものである。ここで、樹脂成分とは、熱硬化性樹脂や熱可塑性樹脂などの樹脂を含み、さらに、必要に応じて炭素粉末や界面活性剤などの添加物を含むものである。
本発明においては、炭素繊維抄紙体などの多孔体に樹脂組成物を含浸した予備含浸体を形成した後、炭化を行なうに先立って、予備含浸体を貼り合わせたり、予備含浸体に熱処理を行なったりすることができる。
本発明において、炭素繊維抄紙体などの多孔体に樹脂組成物を含浸して予備含浸体とした後、樹脂成分を炭化するために、不活性雰囲気下で焼成を行なう。この焼成は、バッチ式の加熱炉を用いることもできるし、連続式の加熱炉を用いることもできる。また、不活性雰囲気は、炉内に窒素ガスやアルゴンガスなどの不活性ガスを流すことにより得ることができる。
本発明において、排水性を向上させる目的で、炭素繊維焼成体に撥水加工を施すことが好ましい。撥水加工は、例えば、炭素繊維焼成体に撥水材を塗布し熱処理することにより行なうことができる。なお、撥水材を用いて撥水加工した場合、前記撥水材は結着材として炭素シートに含まれる。
次に、本発明のガス拡散電極基材について説明する。
本発明の炭素シートは、一方の表面にマイクロポーラス層を形成することで、ガス拡散電極基材として用いることができる。そして本発明のガス拡散電極基材は、炭素シートの面Xの側にマイクロポーラス層を有することが好ましい。面Xの側にマイクロポーラス層を有することによって、マイクロポーラス層を形成するためのフィラー含有塗液が炭素シートによりしみ込みにくくなり、面Yへのフィラー含有塗液のしみ出しがより抑制される。その結果、炭素シートの面内方向のガス拡散性がより向上し、燃料電池の発電性能がより向上する。また、フィラー含有塗液が炭素シートによりしみ込みにくくなり、炭素シートの表層にマイクロポーラス層がより好ましい厚さで形成されるため、生成水の逆拡散により、電解質膜の乾燥がより抑制される。
本発明において、前記したガス拡散電極基材を、両面に触媒層を有する固体高分子電解質膜の少なくとも片面に接合することにより、膜電極接合体を形成することができる。その際、触媒層側にガス拡散電極基材のマイクロポーラス層を配置することにより、より生成水の逆拡散が起こりやすくなることに加え、触媒層とガス拡散電極基材の接触面積が増大し、接触電気抵抗を低減させることができる。
本発明の燃料電池は、本発明のガス拡散電極基材を含むものであり、つまり上述の膜電極接合体の両側にセパレータを有するものである。すなわち、上述の膜電極接合体の両側にセパレータを配することにより燃料電池を構成する。通常、このような膜電極接合体の両側にガスケットを介してセパレータで挟んだものを複数個積層することによって固体高分子型燃料電池を構成する。触媒層は、固体高分子電解質と触媒担持炭素を含む層からなる。触媒としては、通常、白金が用いられる。アノード側に一酸化炭素を含む改質ガスが供給される燃料電池にあっては、アノード側の触媒としては白金およびルテニウムを用いることが好ましい。固体高分子電解質は、プロトン伝導性、耐酸化性および耐熱性の高い、パーフルオロスルホン酸系の高分子材料を用いることが好ましい。このような燃料電池ユニットや燃料電池の構成自体は、よく知られているところである。
・厚さ220μmの炭素シートの作製
炭素繊維径7μm、炭素繊維長12mmの東レ(株)製ポリアクリルニトリル系炭素繊維“トレカ”(登録商標)T300を、水中に分散させて湿式抄紙法により連続的に抄紙した。さらに、バインダーとしてポリビニルアルコールの10質量%水溶液を当該抄紙に塗布して乾燥させ、炭素繊維の目付が44.0g/m2の炭素繊維抄紙体を作製した。ポリビニルアルコールの付着量は、炭素繊維抄紙体100質量部に対して22質量部であった。
炭素繊維の目付を30.0g/m2とし、平板プレスでの熱処理において上下プレス面板の間隔を調整したこと以外は、上記した厚さ220μmの炭素シートの作製に記載した方法に従って、厚さが150μmの炭素シートを作製した。
炭素繊維の目付を22.0g/m2とし、平板プレスでの熱処理において上下プレス面板の間隔を調整したこと以外は、上記した厚さ220μmの炭素シートの作製に記載した方法に従って、厚さが100μmの炭素シートを作製した。
上記にて作製した炭素シートを、撥水材として、PTFE樹脂(“ポリフロン”(登録商標)PTFEディスパージョンD-1E(ダイキン工業(株)製))の水分散液、ないしはFEP樹脂(“ネオフロン”(登録商標)FEPディスパージョンND-110(ダイキン工業(株)製)の水分散液に浸漬することにより、炭素繊維焼成体に撥水材を含浸した。その後、温度が100℃の乾燥機炉内で5分間加熱して乾燥し、撥水加工された炭素シートを作製した。なお、乾燥する際は、炭素シートを垂直に配置し、1分毎に上下方向を変更した。また、撥水材の水分散液は、乾燥後で炭素シート95質量部に対し、撥水材が5質量部付与されるように適切な濃度に希釈して使用した。
<材料>
・炭素粉末A:アセチレンブラック“デンカ ブラック”(登録商標)(電気化学工業(株)製)
・炭素粉末B:線状カーボン:気相成長炭素繊維 “VGCF”(登録商標)(昭和電工(株)製)アスペクト比70
・材料C:撥水材:PTFE樹脂(PTFE樹脂を60質量部含む水分散液である“ポリフロン”(登録商標)PTFEディスパージョンD-1E(ダイキン工業(株)製)を使用)
・材料D:界面活性剤“TRITON”(登録商標)X-100(ナカライテスク(株)製)
上記の各材料を、分散機を用いて混合し、フィラー含有塗液を作製した。このフィラー含有塗液を、スリットダイコーターを用いて、撥水加工された炭素シートの一方の表面上に面状に塗布した後、120℃の温度で10分間、380℃の温度で10分間加熱した。このようにして、撥水加工された炭素シート上にマイクロポーラス層を形成して、ガス拡散電極基材を作製した。ここで用いたフィラー含有塗液には、炭素粉末、撥水材、界面活性剤および精製水を用い、表に示す、配合量を質量部で記載したフィラー含有塗液の組成となるように調整したものを用いた。表に示した材料C(PTFE樹脂)の配合量は、PTFE樹脂の水分散液の配合量ではなく、PTFE樹脂自体の配合量を表す。
白金担持炭素(田中貴金属工業(株)製、白金担持量:50質量%)1.00gと、精製水1.00g、“Nafion”(登録商標)溶液(Aldrich社製“Nafion”(登録商標)5.0質量%)8.00gと、イソプロピルアルコール(ナカライテスク社製)18.00gとを順に加えることにより、触媒液を作製した。
炭素シートおよびガス拡散電極基材の目付は、10cm四方に切り取ったサンプルの質量を、サンプルの面積(0.01m2)で除して求めた。
炭素シートおよびガス拡散電極基材を平滑な定盤にのせ、圧力0.15MPaをかけた状態での測定物がある場合からない場合の高さの差を測定した。異なる部位にて10箇所サンプリングを行い、高さの差の測定値を平均したものを厚さとした。
撥水加工された炭素シートの滑落角は、自動接触角計を用いた滑落法により求めた。装置としては、協和界面科学(株)製の自動接触角計DM-501を用いた。撥水加工された炭素シートの面Yを上側(測定側)にして装置ステージに固定し、イオン交換水10μLの液滴を炭素シートの面Yに着滴させ、1秒間待機させた後、装置ステージとともに撥水加工された炭素シートを傾斜させ、液滴が炭素シート表面を滑落し始めたときの装置ステージの傾斜角度を滑落角とした。
本発明において、撥水材の融点は示差走査熱量測定により行った。装置はセイコーインスツル株式会社(SII社)製DSC6220を用いて、窒素中にて昇温速度2℃/分で、30℃から400℃の温度まで変化させ、その際の吸発熱ピークを観察し、150℃以上の温度での吸熱ピークを撥水材の融点とした。
炭素シートのフッ素強度は、次のようにして求めた。以下、図2を用いて説明する。まず、炭素シート(1)の一方の表面を面X(2)、他方の表面を面Y(3)と仮決めした後、鋭利な刃物により無作為に炭素シート(1)の面直方向断面観察用サンプルを50個作製した。前記50個の炭素シート(1)の断面に対して、走査型電子顕微鏡(SEM)-エネルギー分散型X線分析(EDX)装置を用いて、炭素シート(1)の面直方向にラインスキャンを行い、フッ素強度(フッ素のシグナル強度)の分布(11)を求めた。フッ素強度の測定は加速電圧7kV、拡大倍率300倍、ライン幅20μmの条件で行った。炭素シート(1)の一方の表面から他方の表面に向かう、炭素シートの面直方向の直線に沿って測定したフッ素強度の平均値(12)の50%の値(13)を求め、仮決めした面X(2)に最も近い50%平均フッ素強度を有する面(面XX(5))から、仮決めした面Y(3)に最も近い50%平均フッ素強度を有する面(面YY(6))までの区間(10)において、前記炭素シート(1)を面直方向に3等分して得られる層について、面XX(5)を含む層を層X(7)と仮決めし、面YY(6)を含む層を層Y(9)と仮決めし、層X(7)と層Y(9)に挟まれる中央の層を層Z(8)とした。
上記の<炭素シートの作製>、<撥水加工>および<ガス拡散電極基材の作製>に記載した方法に従って、表1に示す、層の平均フッ素強度が、層X、層Y、層Zの順に小さくなる多孔質の炭素シートを用いたガス拡散電極基材を得た。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。この際、層Yから結着材を多く取り除くことによって層Xと層Yの平均フッ素強度の差が実施例2に対して大きくなるように変更した。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。この際、全体の樹脂組成物付着量を実施例2に対して大きくなるように変更した。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。この際、全体の樹脂組成物付着量を多くしつつ、層Yから結着材を多く取り除くことによって層Xと層Yの平均フッ素強度の差が実施例5に対して大きくなるように変更した。
表1に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。この際、炭素シートの撥水加工に用いる撥水材の種類をテトラフルオロエチレン-ヘキサフルオロプロピレン共重合体(FEP)に変更することで面Yの滑落角が40度以下となるようにした。
表2に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。
ポリアクリロニトリルの長繊維を200℃の温度で10分間の耐炎化処理を行い、水流交絡処理により不織布を作製し、ロールプレスを行った。次いで2000℃の温度の加熱炉に導入し炭化処理することで、厚さ150μmの不織布の炭素繊維焼成体からなる炭素シートを得た。
次に、結着材となる撥水材として、上記の<撥水加工>で用いたPTFE樹脂と、<ガス拡散電極基材の作製>で用いた炭素粉末Aとを、固形分の質量比が1:1となるように混合し、撥水材の水分散液を作製した(撥水材の水分散液の濃度は、乾燥後で炭素シート95質量部に対し、撥水材が5質量部付与されるように調整した)。次に、不織布の炭素繊維焼成体からなる炭素シートを、アルミバットに満たした撥水材の水分散液に浸漬し、一定のクリアランスをあけて水平に2本配置したロール(2本のうちの一方のロールはドクターブレードを有する平滑な金属ロール、他方のロールは凹凸のついたグラビアロール)に挟んで絞り、炭素シートの一方の表面と他方の表面の撥水材の付着量に差を付けた。その後、380℃の温度で10分間加熱して乾燥した。このようにして、表2に示す、層の平均フッ素強度が、層X、層Y、層Zの順に小さくなる撥水加工された炭素シートを作製した。
表2に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。この際、層Yから結着材を少量取り除くことによって層Xと層Yの平均フッ素強度の差が実施例2に対して小さくなるように変更した。
上記の<炭素シートの作製>に記載した方法において、炭素繊維抄紙体から樹脂組成物の含浸液を2本のロールに挟んで絞る工程において、2本とも同じ形状の金属ロールを用いたこと以外は、表2に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。これにより、両面とも近い結着材量が付着することによって、層Xと層Yの平均フッ素強度が同じ値となった。
上記の<炭素シートの作製>に記載した方法において、炭素繊維抄紙体に樹脂組成物を含浸させる際に、一方の表面側からグラビア塗布により樹脂組成物を付着させたこと以外は、表2に示す構成にて、実施例1と同様にして炭素シートおよびガス拡散電極基材を得た。
2:面X
3:面Y
4:50%平均フッ素強度未満の層
5:面XX
6:面YY
7:層X
8:層Z
9:層Y
10:区間
11:フッ素強度の分布
12:フッ素強度の平均値
13:フッ素強度の平均値の50%の値
Claims (10)
- 炭素繊維および結着材を含む多孔質の炭素シートであって、
一方の表面に最も近い50%平均フッ素強度を有する面から、他方の表面に最も近い50%平均フッ素強度を有する面までの区間において、前記区間を前記炭素シートの面直方向に3等分して得られる層について、一方の表面に近い層と他方の表面に近い層のうち、層の平均フッ素強度がより大きい層を層X、より小さい層を層Yとし、層Xと層Yの間の層を層Zとすると、層の平均フッ素強度が、層X、層Y、層Zの順に小さくなることを特徴とする、炭素シート。 - 層Yの平均フッ素強度を1としたときに、層Xの平均フッ素強度が1.30~9.00である、請求項1に記載の炭素シート。
- 層Yの平均フッ素強度を1としたときに、層Zの平均フッ素強度が0.10~0.90である、請求項1または2に記載の炭素シート。
- 層Yに最も近い表面を面Yとしたときに、
面Yにおける水の滑落角が40度以下である、請求項1~3のいずれかに記載の炭素シート。 - 炭素シートが撥水材を含み、
前記撥水材の融点が、200~320℃の範囲内である、請求項1~4のいずれかに記載の炭素シート。 - 前記撥水材が、テトラフルオロエチレン-ヘキサフルオロプロピレン共重合体(FEP)および/またはテトラフルオロエチレン-パーフルオロアルキルビニルエーテル共重合体(PFA)を含む、請求項5に記載の炭素シート。
- 厚さが50~230μmである、請求項1~6のいずれかに記載の炭素シート。
- 層Xに最も近い表面を面Xとしたときに、請求項1~7のいずれかに記載の炭素シートの面X側にマイクロポーラス層を有する、ガス拡散電極基材。
- 前記マイクロポーラス層が炭素粉末を含み、前記炭素粉末がアスペクト比30~5000の線状カーボンを含む、請求項8に記載のガス拡散電極基材。
- 請求項8または9に記載のガス拡散電極基材を含む、燃料電池。
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US (1) | US20170244107A1 (ja) |
EP (1) | EP3228588B1 (ja) |
JP (1) | JP7129751B2 (ja) |
CA (1) | CA2962722C (ja) |
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Cited By (3)
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WO2018096895A1 (ja) * | 2016-11-24 | 2018-05-31 | 旭化成株式会社 | 炭素フォーム、膜電極複合体 |
JP2018156818A (ja) * | 2017-03-17 | 2018-10-04 | 東レ株式会社 | ガス拡散電極、および、燃料電池 |
US11655152B2 (en) | 2017-03-13 | 2023-05-23 | Asahi Kasei Kabushiki Kaisha | Carbon foam and manufacturing method thereof |
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KR102664327B1 (ko) * | 2018-12-05 | 2024-05-08 | 주식회사 제이앤티지 | 일방향으로 배향된 탄소 섬유를 포함하는 탄소 기재 및 이를 채용한 기체확산층 |
FR3098357B1 (fr) * | 2019-07-01 | 2021-12-24 | Commissariat Energie Atomique | Procédé de fabrication d’un dispositif de diffusion gazeuse à propriétés électriques améliorées |
KR20210074896A (ko) * | 2019-12-12 | 2021-06-22 | 현대자동차주식회사 | 연료전지용 기체확산층 및 그 제조방법 |
DE102020121892A1 (de) * | 2020-08-20 | 2022-02-24 | Carl Freudenberg Kg | Gasdiffusionslage für Brennstoffzellen mit verbesserten Biegeeigenschaften |
CN114709435B (zh) * | 2022-06-02 | 2022-09-13 | 武汉氢能与燃料电池产业技术研究院有限公司 | 一种气体扩散层中复合微孔层及其制备方法 |
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JP2020128330A (ja) * | 2016-11-24 | 2020-08-27 | 旭化成株式会社 | 炭素フォーム、膜電極複合体 |
WO2018096895A1 (ja) * | 2016-11-24 | 2018-05-31 | 旭化成株式会社 | 炭素フォーム、膜電極複合体 |
KR20190040270A (ko) * | 2016-11-24 | 2019-04-17 | 아사히 가세이 가부시키가이샤 | 탄소 폼, 막 전극 복합체 |
CN109863129A (zh) * | 2016-11-24 | 2019-06-07 | 旭化成株式会社 | 碳泡沫、膜电极复合体 |
JPWO2018096895A1 (ja) * | 2016-11-24 | 2019-06-24 | 旭化成株式会社 | 炭素フォーム、膜電極複合体 |
AU2017364461B2 (en) * | 2016-11-24 | 2020-01-16 | Asahi Kasei Kabushiki Kaisha | Carbon foam and membrane electrode composite |
KR102428982B1 (ko) * | 2016-11-24 | 2022-08-03 | 아사히 가세이 가부시키가이샤 | 탄소 폼, 막 전극 복합체 |
KR102242600B1 (ko) * | 2016-11-24 | 2021-04-20 | 아사히 가세이 가부시키가이샤 | 탄소 폼, 막 전극 복합체 |
JP7096855B2 (ja) | 2016-11-24 | 2022-07-06 | 旭化成株式会社 | 炭素フォーム、膜電極複合体 |
US11171339B2 (en) | 2016-11-24 | 2021-11-09 | Asahi Kasei Kabushiki Kaisha | Carbon foam and membrane electrode assembly |
KR20210043753A (ko) * | 2016-11-24 | 2021-04-21 | 아사히 가세이 가부시키가이샤 | 탄소 폼, 막 전극 복합체 |
US11655152B2 (en) | 2017-03-13 | 2023-05-23 | Asahi Kasei Kabushiki Kaisha | Carbon foam and manufacturing method thereof |
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JP7114858B2 (ja) | 2017-03-17 | 2022-08-09 | 東レ株式会社 | ガス拡散電極、および、燃料電池 |
Also Published As
Publication number | Publication date |
---|---|
EP3228588B1 (en) | 2020-04-29 |
JP7129751B2 (ja) | 2022-09-02 |
EP3228588A4 (en) | 2018-06-06 |
CA2962722A1 (en) | 2016-04-21 |
JPWO2016060045A1 (ja) | 2017-07-27 |
US20170244107A1 (en) | 2017-08-24 |
TW201622220A (zh) | 2016-06-16 |
CA2962722C (en) | 2023-04-04 |
EP3228588A1 (en) | 2017-10-11 |
TWI692143B (zh) | 2020-04-21 |
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