2369results about "Collectors/separators" patented technology

The present disclosure relates to a field of a fuel cell test, and in particular, to a method and an apparatus for optimizing design based on performance evaluation of a gas diffusion layer of a fuel cell. The method includes: determining an overall porosity of the gas diffusion layer of the fuel cell according to production requirements, and obtaining a plurality of porosity structures with the overall porosity; obtaining performance evaluation indexes of the gas diffusion layer of the fuel cell, and constructing a performance evaluation system for the gas diffusion layer of the fuel cell; calculating, with reference to evaluation functions and index weight ratios, performance comprehensive scores of the plurality of porosity structures in the performance evaluation system of the gas diffusion layer of the fuel cell; determining an optimal design scheme in the plurality of porosity structures according to the performance comprehensive scores.

The present invention relates to a composite high-temperature proton exchange membrane, a preparation method thereof, and an application thereof. The preparation method of the composite high-temperature proton exchange membrane comprises the following steps: S1. Mix a polymer represented by formula (I), a polymer represented by formula (II), and a solvent to obtain a casting solution, pour it, and dry it to obtain a composite film; S2. Immerse the composite film obtained in step S1 in an alkaline solution of borax, wash it, dry it, and then adsorb phosphoric acid to obtain the composite high-temperature proton exchange membrane. The composite high-temperature proton exchange membrane prepared by the preparation method of the present invention still maintains good proton conductivity / has high proton conductivity, has a high peak power density, and has high tensile strength and high phosphoric acid retention rate under the condition of low phosphoric acid adsorption amount.

To provide a fuel battery cell that can improve durability of a membrane electrode joined body, and a method for designing a fuel battery cell.SOLUTION: A fuel battery cell comprises: a membrane electrode joined body that generates power by using reaction gas; a pair of gas diffusion layers that sandwich the membrane electrode joined body; and a pair of separators 14 that sandwich the membrane electrode joined body and the pair of gas diffusion layers. The gas diffusion layer has a Young's modulus of 1800 MPa or more and a thickness of 0.12 mm or more and 0.25 mm or less. The separator 14 has a groove 29 that has a branch part 31 and forms a channel 28 for supplying the reaction gas to the membrane electrode joined body. A value obtained by dividing the diameter D of an inscribed circle 33 of the branch part 31 in the groove 29 by a groove width W of a general part 32 other than the branch part 31 in the groove 29 is 2.5 or less.SELECTED DRAWING: Figure 3

The invention belongs to the technical field of flow batteries, and discloses a flexible graphite bipolar plate with a self-repairing function and a preparation method and application thereof. The flexible graphite bipolar plate comprises a flexible graphite-polymer composite matrix, microcapsules and a graphene conductive layer, wherein the graphene conductive layer is arranged on the surface of the flexible graphite-polymer composite matrix; the microcapsule is dispersed in the flexible graphite-polymer composite matrix, the core of the microcapsule is a liquid metal alloy, the liquid metal alloy contains Ga, and the shell of the microcapsule is polyurethane. The microcapsules containing the liquid metal alloy are introduced into the flexible graphite bipolar plate in situ, and when the flexible graphite bipolar plate generates microcracks due to mechanical stress, thermal cycle and the like, the internal microcapsules are broken at the first time to release the liquid metal and fill the cracks, so that the graphite bipolar plate still keeps relatively high mechanical strength and air tightness, and the service life of the flexible graphite bipolar plate is prolonged. Therefore, the conductive stability and the use durability of the flow battery are improved.

The utility model relates to a bipolar plate of a hydrogen fuel cell and the hydrogen fuel cell, comprising a substrate on which a manifold region, a gap bridge region, a distribution region and an activation region are arranged; the activation area is used for catalyzing and reacting the gas; the activation area comprises a flow channel unit, the flow channel unit comprises a plurality of gas flow channels extending in the first direction, each gas flow channel comprises a straight area, a bent area, a first variable-diameter area and a second variable-diameter area which are sequentially arranged in the first direction, the first direction is the same as the length direction of the substrate, and the second direction is the same as the length direction of the substrate. The straight areas of every two adjacent gas flow channels are parallel to each other, and the bending directions of the bending areas of every two adjacent gas flow channels are parallel to each other. The bipolar plate disclosed by the utility model can improve the performance of the electric pile, and the electric pile adopting the variable-flow channel is higher in power for the electric pile with the same number of pieces. Moreover, the bipolar plate can reduce in-plane power generation deviation, so that electrochemical reaction is more uniform, the consistency of an electric pile is better, and the service life is effectively prolonged.

The invention belongs to the technical field of electrochemical energy storage, and discloses a flow battery composite membrane material and a preparation method thereof, and the preparation method comprises the following steps: spraying a ZIF-8 metal organic framework solution to the positive electrode side of a microporous diaphragm, and drying to obtain the flow battery composite membrane material. According to the zinc-bromine flow battery and the preparation method thereof, ZIF-8 acts on the positive electrode side of the microporous diaphragm, ZIF-8 shows good chemical stability in an acidic electrolyte environment of the zinc-bromine flow battery and is not easily oxidized and degraded by bromine, and a stable framework ensures that a screening pore channel is kept complete in long-term operation and continuously plays a role in resisting bromine, so that the corrosion of a zinc negative electrode and the loss of bromine active substances are reduced, and the service life of the zinc-bromine flow battery is prolonged. The problems of low bromine permeation and bromine reaction rate on the positive electrode side of the zinc-bromine flow battery and the like can be effectively solved, and the coulombic efficiency and the voltage efficiency can be remarkably improved, so that the microporous diaphragm with excellent comprehensive performance is obtained.

The invention relates to a solid oxide fuel cell and a preparation method thereof. The solid oxide fuel cell comprises a sheet substrate, a first cell monomer and a second cell monomer, wherein the first cell monomer and the second cell monomer are fixed on the front and back surfaces of the sheet substrate; each of the first battery monomer and the second battery monomer comprises a porous supporting layer, an anode functional layer, an electrolyte layer and a cathode functional layer which are sequentially stacked and connected; the sheet body substrate is connected between the porous support layer of the first battery monomer and the porous support layer of the second battery monomer; a separation groove is formed in the sheet body substrate, and a fuel gas flow channel is formed among the separation groove, the first battery monomer and the second battery monomer. After the pipeline connected with the fuel gas is communicated with the fuel gas flow channel, the fuel gas only flows in the fuel gas flow channel, and the fuel gas flow channel has good sealing performance. And the porous supporting layer, the anode functional layer, the electrolyte layer and the cathode functional layer are planar sheet bodies which are printed and formed layer by layer, so that the manufacturing difficulty is low, industrial large-scale manufacturing is facilitated, and the production cost is reduced.

The invention discloses a high-potential-corrosion-resistant composite coating as well as a preparation method and application thereof. The high-potential-corrosion-resistant composite coating comprises a metal transition layer, a graphite-like amorphous carbon layer and a SnO2 hole sealing layer which are sequentially formed on the surface of the metal bipolar plate serving as a substrate, wherein the SnO2 hole sealing layer is prepared in an atomic layer deposition mode. According to the high-potential-corrosion-resistant composite coating provided by the invention, the SnO2 layer is deposited on the surface of the amorphous carbon coating, so that the effect of closing amorphous carbon defects is achieved, and the high-potential-corrosion-resistant composite coating has excellent corrosion-resistant protection performance under 1.6 V high-potential corrosion.

The invention belongs to the technical field of bipolar plate materials for flow batteries, relates to a composite bipolar plate material as well as a preparation method and application thereof, and is suitable for bipolar plate materials for flow batteries. According to the bipolar plate of the flow battery, the three-dimensional porous foam metal is used as the matrix and is positioned in the middle layer, so that the overall strength and toughness of the bipolar plate can be improved, and meanwhile, the problems of local overheating and the like caused by non-uniform heating of zinc deposition in a charge-discharge test of a sedimentary flow battery such as a zinc ferroelectric pile are solved, so that the long-term operation of the battery is influenced; and the porous foam metal can well transfer heat and enable the heat to be uniformly distributed, so that the porous foam metal has a good application prospect in the sedimentary flow battery. The composite material is adhered to the two sides of the bipolar plate through a hot pressing process, so that the corrosion resistance of the bipolar plate can be ensured, meanwhile, the foam metal constructs an efficient conductive network in the bipolar plate, the foam metal and the composite material can form a synergistic conductive effect, and the electron transmission capability of the bipolar plate is also improved; in the manufacturing process, carbon paper / carbon fiber cloth is added to the upper side and the lower side at the same time, so that the surface resistance of the bipolar plate is reduced, and the performance of the bipolar plate in a flow battery is further improved.

The invention relates to a Y-doped Ti-Mn-based solid hydrogen storage alloy and a preparation method thereof, belongs to the technical field of hydrogen storage alloy materials, and has the advantages of easiness in activation, high hydrogen absorption and desorption speed, moderate hydrogen absorption and desorption plateau pressure and long cycle life. The invention provides a Y-doped Ti-Mn-based hydrogen storage alloy, which is characterized in that the chemical general formula of the hydrogen storage alloy is Ti1-x-yYxZryMn2-w-vVwFev, in the formula, x, y, w and v represent atomic ratios, 0.02 < = x < = 0.08, 0.05 < = y < = 0.15, 0.3 < = w < = 0.5, and 0.1 < = v < = 0.2. The hydrogen storage alloy is excellent in hydrogen storage performance and can be completely activated by absorbing hydrogen for the first time under the conditions of 25 DEG C and 3 MPa, the hydrogen storage capacity is larger than or equal to 1.90 wt%, the hydrogen absorption plateau pressure is larger than or equal to 0.35 MPa, the hydrogen desorption plateau pressure is smaller than or equal to 0.26 MPa, and the hydrogen absorption retention rate of the alloy is larger than or equal to 97.52% after the alloy is cycled for 1000 times.

The invention discloses a preparation method of a TPU coated Al2O3 porous polymer electrolyte membrane, an electrolyte membrane and application thereof, and the preparation method comprises the following steps: S1, adding TPU into a solvent, and violently stirring for 12 hours to obtain a TPU solution; s2, adding nano aluminum oxide into the TPU solution, and violently stirring for 12 hours to obtain a TPU-coated AlO solution; and S3, sucking the TPU-coated AlO solution onto a glass plate, removing bubbles in vacuum, transferring the TPU-coated AlO solution into water, standing for 2 hours, stripping an obtained electrolyte membrane from the glass plate after the solvent and the water are completely replaced, taking out the electrolyte membrane, and drying the electrolyte membrane to obtain the TPU-coated AlO porous polymer electrolyte membrane. According to the preparation method of the TPU coated Al2O3 porous polymer electrolyte membrane, the electrolyte membrane and the application of the electrolyte membrane, an organic-inorganic composite porous polymer membrane is prepared through a physical mixing and phase transfer method, and the electrolyte membrane not only has relatively thin thickness and relatively light weight, but also has certain lithium dendrite resisting capability and can improve the safety of liquid absorption capability; the requirement of quick charging can be met, and the safety and performance of the battery are improved.

A flow battery bipolar plate with a novel flow channel relates to the technical field of flow batteries, and comprises a bipolar plate body and two groove areas which are arranged on the bipolar plate body in a central symmetry manner, the groove area comprises an infusion hole, a transverse groove and a plurality of longitudinal grooves; the plurality of longitudinal grooves in the two groove areas are alternately arranged in an interdigital manner and are not communicated with each other; the special-shaped grooves are communicated with the transverse grooves; the infusion hole is formed in the special-shaped groove; a fan-shaped shunting column, a rectangular shunting column and a triangular shunting column are arranged in the special-shaped groove; the longitudinal groove is S-shaped; a first extending part and a second extending part are arranged on the bipolar plate body. According to the utility model, the flow channel structure of the bipolar plate is improved, so that the speed of electrolyte entering the battery is effectively reduced, the electrolyte is distributed more uniformly, the internal concentration polarization is reduced, the overall voltage drop and the pumping power loss are reduced, and the electrochemical performance of the battery is improved.

The invention relates to a method for manufacturing a bipolar plate (10, 51) for an electrochemical cell unit (53) for converting electrochemical energy into electrical energy as a fuel cell unit (1) and / or for converting electrical energy into electrochemical energy as an electrolytic cell unit (49) having stacked electrochemical cells (52), the method comprising the steps of: providing a first plate 64) and a second plate (65), stacking the first plate (64) and the second plate (65) on top of one another such that inner surfaces (66) of the first and second plate (64, 65) lie on top of one another, applying contact forces to the first and second plates (64, 65) by means of negative pressure in a negative pressure chamber (104) relative to an ambient pressure so that, as a result of the contact forces applied by the ambient pressure, the inner surfaces (66) of the first and second plate (64, 65) lie on top of one another with an additional compression force in a contact region (68) due to the applied contact forces, producing at least one welded joint (69) between the first and second plate (64, 65) by means of a laser beam (74), forming connection channels (89) for process fluids in the first and / or second plate (64, 65), the channels opening into fluid openings (41) in the bipolar plates (10), 51) and into channels (12, 13, 14) for process fluids in the bipolar plates (10, 51), forming connection openings (93) in the first and / or second plate (64, 65) which connect the connection channels (89) to the channels (12, 13, 14) for process fluids in the bipolar plates (10, 51), the connection openings (93) being formed in the first and / or second plate (64, 65) by means of a laser beam (74).

The invention discloses a preparation method of an integrated collector plate for a vanadium battery. The preparation method comprises the following steps: preparing foamed nickel deposited by carbon nanotubes; pressing the conductive particles into sheets, sequentially putting the conductive sheets, the modified foamed nickel and the conductive sheets into a mold, and integrally forming by using a hot press to obtain the composite bipolar plate. Silver-copper composite powder is prepared by plating silver on the surface of copper powder through chemical plating, conductive adhesive containing silver-copper metal powder is prepared, and a copper plate and a composite bipolar plate are bonded through the conductive adhesive to prepare the integrated collector plate. The foamed nickel is used as a framework material, the interface between the foamed nickel and the carbon composite layer is improved by depositing the carbon nanotubes on the surface of the foamed nickel, the mechanical strength and the conductivity of the composite bipolar plate are improved, nano-scale silver particles on the surface of the copper powder can be melted by performing heat treatment on the silver-copper composite powder, a continuous silver film is formed, and the conductivity of the composite bipolar plate is improved. The conductivity and oxidation resistance of the conductive adhesive are improved, and the contact resistance between the bipolar plate and a copper plate is reduced, so that the performance of the flow battery is improved.

The present application discloses a metal composite bipolar plate, a processing method, and an application thereof. The metal composite bipolar plate includes an intermediate metal plate layer, wherein the upper and lower surfaces of the intermediate metal plate layer are respectively welded with a bipolar plate structural layer, the intermediate metal plate layer is fully encapsulated in the bipolar plate structural layer, and the intermediate metal plate layer and the bipolar plate structural layer are made of different metal materials; an atomic diffusion layer exists at the interface between the upper and lower surfaces of the intermediate metal plate layer and the bipolar plate structural layer; a plurality of flow channels are formed by stamping on the surface of the bipolar plate structural layer, and the corners at the bottom of the flow channels and the corners at the opening are both configured as chamfered structures. The present application uses titanium / titanium alloy and aluminum / aluminum alloy to form a composite plate combination. By improving the bipolar plate flow channels and adjusting the interface bonding method of the composite layer plates, cracking or warping at the flow channel corners during the stamping process is avoided, while improving the performance of the bipolar plate and reducing production costs.

The invention relates to the technical field of flow batteries, in particular to a flow battery electrode frame assembly and a battery unit.The flow battery electrode frame assembly comprises a mother frame, a public flow channel is formed in the mother frame, an internal flow channel set and an electrode cavity are formed in the mother frame, and the internal flow channel set communicates with the public flow channel and the electrode cavity; when the two adjacent mother frames are attached face to face, the internal flow channel sets on the two mother frames coincide and communicate with each other in the thickness direction of the mother frames, and the common flow channels on the two mother frames communicate with each other. The son frame is arranged on the mother frame; and the bipolar plate is arranged between the secondary frame and the primary frame. The electrode frame has the effect of increasing the depth of the flow channel within the limited thickness of the electrode frame.

An end fuel cell assembly 10N has an anode face with a first end (18, Figure 3) having an anode outlet (315, Figure 3) fluidly connected to an anode inlet (325, Figure 3) across an anode face flow fie

The invention discloses a porous material embedded micro-channel structure polar plate suitable for a fuel cell, and belongs to the technical field of fuel cells. The porous material embedded micro-channel structure polar plate suitable for the fuel cell is provided with a flow field groove, a porous flow field is arranged in the flow field groove, the porous flow field is a porous material with a continuous pore structure, and a micro-channel forming a gas transmission path is processed on the surface of the porous material. The continuous pore structure of the porous material forms a liquid water transmission path under the action of capillary force, so that the uniformity of gas distribution in a flow field is improved, meanwhile, water accumulation possibly occurring in a traditional flow channel is effectively avoided, the thickness and the volume of the fuel cell are greatly reduced, the power density can be greatly improved, and the service life of the fuel cell is prolonged. The electron transverse transmission distance is effectively shortened, and the ohmic loss is reduced.

The invention relates to a method for producing a coated metal substrate plate (10), wherein a metal substrate plate (1) is coated with an adhesion promoter layer (2) in a first surface region by means of an arc vapour deposition (Arc-PVD) method, at least one single layer of a tetrahedral amorphous carbon layer (3) of the ta-C:H type having at least 3 wt.% hydrogen is formed with a first layer thickness in the range from 10 to 500 nm on the adhesion promoter layer (2) by means of the arc vapour deposition (Arc-PVD) method, wherein a temperature of the metal substrate plate (1), of the adhesion promoter layer (2) and of the tetrahedral amorphous carbon layer (3) is maintained in the range from 100 to 180°C during coating. The invention also relates to a coated metal substrate plate (10) produced thereby and to an electrochemical cell (20) comprising at least one such metal substrate plate, and to a coating installation (200) for carrying out the method.

A bipolar plate-gas diffusion layer (GDL) assembly for a polymer-electrolyte-membrane fuel cell includes a flat metallic bipolar plate and a porous metal GDL adjacent to and in direct contact with the flat metallic bipolar plate. The porous metal GDL includes flow channels defined by flow channel walls with flow channel surfaces. The flow channel walls and flow channel surfaces have an average porosity generally equal to an average porosity of an interior of the porous metal GDL.

The application relates to the technical field of all-vanadium redox flow batteries, and discloses an integrated electrode plate and a preparation method and application thereof, which comprises the following steps: mixing and calcining a metal organic framework material and polyvinylpyrrolidone to obtain a porous carbon material; uniformly melting and mixing the porous carbon material, resin and conductive carbon material, and performing die forming to obtain a modified bipolar plate; using silver-coated copper powder as a conductive filler, and using epoxy modified acrylic resin as an organic carrier to prepare ultraviolet light curing silver-coated copper conductive adhesive; and bonding the electrode and the modified bipolar plate through ultraviolet light curing to prepare the integrated electrode plate. The porous carbon is obtained by using a polyvinylpyrrolidone-assisted limited carbonization method, the conductivity of the bipolar plate is improved, epoxy modified acrylic resin is used as the organic carrier, the silver-coated copper powder is uniformly distributed in the organic carrier, the conductivity of the conductive adhesive is improved, and the integrated electrode plate improves the performance of the flow battery.

The invention relates to a flow frame unit (12) for a redox flow battery and a cell stack (10) comprising at least two flow frame units (12).

To provide a fuel cell that can be constructed thinly while ensuring sufficient thickness of the gas diffusion layer. [Solution] A fuel cell cell that generates electricity by the reaction of a reaction gas comprises a membrane electrode assembly having an electrolyte membrane and a catalyst layer, a gas diffusion layer laminated on the membrane electrode assembly and made of a porous metal, and a separator laminated on the gas diffusion layer and parallel to the plane direction of the membrane electrode assembly, wherein the gas diffusion layer has grooves through which the reaction gas flows on the separator side.

The invention relates to an electrochemical cell assembly (10) comprising a stack (16) of cell units (18), wherein in said stack there is provided a fluid inlet manifold (28) and a fluid outlet manifold (30), each cell unit has a fluid inlet port (38) being in communication with the fluid inlet manifold and a fluid outlet port (40) being in communication with the fluid outlet manifold, each cell unit defines an inner fluid flow path (36) for fluid to flow from the fluid inlet port to the fluid outlet port, each cell unit has a fluid permeability along its fluid flow path, an average fluid permeability of the cell units in an upper half (52) of the stack is higher than an average fluid permeability of the cell units in a lower half (54) of the stack.

To provide a fuel cell cell having a separator that can improve drainage performance. [Solution] The fuel cell cell comprises a membrane electrode assembly, a pair of gas diffusion layers provided so as to sandwich the membrane electrode assembly, and a pair of separators provided so as to sandwich the pair of gas diffusion layers. At least one of the pair of separators has a flow channel portion through which the reaction gas flows on the surface facing the gas diffusion layer, and a rib portion provided adjacent to the flow channel portion and in contact with the gas diffusion layer. The flow channel portion has a bottom surface away from the gas diffusion layer and a side portion connecting the bottom surface and the rib portion, and the side portion is provided with a groove extending from the connection portion with the rib portion toward the bottom surface.

A separator for a fuel cell includes a rectangular plate-shaped body. The body forms passages through which gas flows. The body includes central regions and a reversing region. The central regions extend along one side of the body, and are arranged in a direction in which another side of the body that intersects the one side extends. The passages include multiple central passage sections that extend in the longitudinal direction through each central region, and a reversing passage section that extends through the reversing region and connects the central passage sections of adjacent ones of the central regions. The ribs are formed such that two or more of the central passage sections are formed in each of the central regions, and the reversing passage section in the reversing region is connected to two or more of the central passage sections in the corresponding central region.

The invention discloses a composite forming process of a bipolar plate of a multilayer flow battery, which comprises the following steps of: placing a metal foil in a punching machine for rolling and punching to obtain a perforated metal foil; cleaning the perforated metal foil with alcohol, stacking the flexible graphite paper, the perforated metal foil and the flexible graphite paper according to a sandwich structure, and rolling and forming by a roller press to obtain a composite bipolar plate; and carrying out infiltration, cleaning, curing and drying treatment on the pressed composite bipolar plate to obtain the multilayer flow battery bipolar plate. According to the composite forming process of the bipolar plate of the multilayer flow battery, the perforated metal foil is used as the interlayer, the flexible graphite paper is used as the upper layer and the lower layer, and a'sandwich 'structure is constructed by adopting a sprint process, so that the prepared bipolar plate of the multilayer flow battery is high in combination degree, and layering of the metal foil and the flexible graphite paper can be avoided; the bending strength and the conductivity of the bipolar plate of the multilayer flow battery are effectively improved, the contact resistance is reduced, and a better conductive network is constructed.

The invention relates to a fuel cell membrane electrode assembly, a single cell and a fuel cell, the fuel cell membrane electrode assembly comprises a proton exchange membrane and a membrane electrode frame, the membrane electrode frame comprises a first frame connected to the cathode side of the proton exchange membrane, and one side, connected with the proton exchange membrane, of the first frame is further connected with a second frame; the thickness of the first frame is smaller than that of the second frame. According to the fuel cell, the first frame and the second frame are asymmetrically designed on the two sides of the proton exchange membrane, so that a space condition can be provided for increasing the flow channel depth of a cathode distribution area, the air or oxygen flow resistance on the cathode side is remarkably reduced, and the overall electrochemical reaction efficiency of the fuel cell is improved. Due to the low-density characteristic of hydrogen, the overall flow resistance of the anode is relatively small, so that the flow channel depth of the anode side distribution area is not changed or is properly reduced. And meanwhile, the first frame and the second frame form the membrane electrode frame with the double-layer structure, so that the packaging process is reduced, and the material cost and the process cost are reduced.

The invention discloses an integrated gas diffusion layer with a hydrophilic and hydrophobic structure and a preparation method and application thereof, and belongs to the technical field of fuel cells. The integrated gas diffusion layer structure comprises a hydrophilic layer and a hydrophobic layer, the hydrophilic layer is a planar layer, the hydrophobic layer is a mixed layer with ridges I and grooves I, no transition layer exists between the hydrophilic layer and the hydrophobic layer, the hydrophilic layer is located between the hydrophobic layer and a fuel cell membrane electrode catalyst layer, and the hydrophobic layer is located between a fuel cell bipolar plate and the hydrophilic layer. The preparation method of the integrated gas diffusion layer comprises the following steps: sequentially blade-coating hydrophobic layer slurry and hydrophilic layer slurry into a mold with a ridge II and a groove II, and finally demolding to obtain the integrated gas diffusion layer. The integrated gas diffusion layer is used for the gas diffusion layer of the proton exchange membrane fuel cell, the hydrophobic layer has a larger contact angle, gas transmission and discharge of generated water are facilitated, the hydrophilic layer separates out the water through capillary action, the mass transfer resistance is reduced, and the performance of a membrane electrode is improved.