WO2007113592A1 - Ensemble pour pile a combustible - Google Patents
Ensemble pour pile a combustible Download PDFInfo
- Publication number
- WO2007113592A1 WO2007113592A1 PCT/GB2007/050167 GB2007050167W WO2007113592A1 WO 2007113592 A1 WO2007113592 A1 WO 2007113592A1 GB 2007050167 W GB2007050167 W GB 2007050167W WO 2007113592 A1 WO2007113592 A1 WO 2007113592A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- gas diffusion
- membrane
- layer
- assembly
- flow field
- Prior art date
Links
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Classifications
-
- 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
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/241—Grouping of fuel cells, e.g. stacking of fuel cells with solid or matrix-supported electrolytes
-
- 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
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
-
- 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
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
- H01M8/0286—Processes for forming seals
-
- 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
- H01M8/1004—Fuel cells with solid electrolytes characterised by membrane-electrode assemblies [MEA]
-
- 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
- H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
- H01M8/0273—Sealing or supporting means around electrodes, matrices or membranes with sealing or supporting means in the form of a frame
-
- 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
- H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
- H01M8/1018—Polymeric electrolyte materials
- H01M8/102—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer
- H01M8/1023—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes
-
- 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
- H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
- H01M8/1018—Polymeric electrolyte materials
- H01M8/1039—Polymeric electrolyte materials halogenated, e.g. sulfonated polyvinylidene fluorides
-
- 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 an assembly suitable for use in a proton exchange membrane fuel cell.
- the assembly comprises at least one membrane electrode assembly and at least one flow field plate.
- a fuel cell is an electrochemical cell comprising two electrodes separated by an electrolyte.
- a fuel e.g. hydrogen or methanol
- an oxidant e.g. oxygen or air
- Electrochemical reactions occur at the electrodes, and the chemical energy of the fuel and the oxidant is converted to electrical energy and heat.
- Fuel cells are a clean and efficient power source, and may replace traditional power sources such as the internal combustion engine in both stationary and automotive power applications.
- the electrolyte is a solid polymer membrane which is electronically insulating but ionically-conducting.
- Proton- conducting membranes based on perfluorosulphonic acid materials are typically used, and protons, produced at the anode, are transported across the membrane to the cathode, where they combine with oxygen to create water.
- the principle component of a PEM fuel cell is known as a membrane electrode assembly (MEA) and is essentially composed of five layers.
- the central layer is the polymer membrane.
- an electrocatalyst layer containing an electrocatalyst, which is tailored for the different requirements at the anode and the cathode.
- an electrocatalyst layer containing an electrocatalyst, which is tailored for the different requirements at the anode and the cathode.
- a gas diffusion substrate adjacent to each electrocatalyst layer there is a gas diffusion substrate.
- the gas diffusion substrate must allow the reactants to reach the electrocatalyst layer and must conduct the electric current that is generated by the electrochemical reactions. Therefore the substrate must be porous and electrically conducting.
- the MEA can be constructed by several methods.
- the electrocatalyst layer may be applied to the gas diffusion substrate to form a gas diffusion electrode.
- Two gas diffusion electrodes can be placed either side of a membrane and laminated together to form the five-layer MEA.
- the electrocatalyst layer may be applied to both faces of the membrane to form a catalyst coated membrane.
- gas diffusion substrates are applied to both faces of the catalyst coated membrane.
- an MEA can be formed from a membrane coated on one side with an electrocatalyst layer, a gas diffusion substrate adjacent to that electrocatalyst layer, and a gas diffusion electrode on the other side of the membrane.
- Flow field plates are used to separate the MEAs.
- the plates perform several functions: supplying the reactants to the MEAs, removing products, providing electrical connections and providing physical support.
- Two MEAs may be separated by a single bipolar plate, which contacts the anode of a first MEA and the cathode of a second MEA.
- the bipolar plate supplies fuel to the first MEA and air or oxygen to the second MEA.
- the bipolar plate may also perform a cooling function if coolant is supplied to coolant channels within the bipolar plate.
- two MEAs may be separated by two monopolar plates.
- a first monopolar plate contacts the anode of a first MEA and a second monopolar plate contacts the cathode of the second MEA.
- the two monopolar plates may be in contact or may be separated by a cooling plate.
- the flow field plates and MEAs in the stack are typically compressed together at pressures from 50 to 200psi absolute, using for example a bladder or piston system or a series of bolts located in stack end plates.
- Fuel cell stack assembly is a complex process wherein numerous individual components must be aligned and integrated. It is not uncommon for individual components to be damaged during stack assembly and it can be difficult to achieve the correct alignment and integration of the various components. Failure of a single MEA in a fuel cell stack can necessitate disassembly of the entire stack and significant disruption of the power supply.
- WO 2005/020356 discloses an MEA wherein encapsulation films, each comprising a backing layer and an adhesive layer, are interposed between the membrane and the gas diffusion substrates such that the backing layer contacts the gas diffusion substrate and the adhesive layer impregnates into the gas diffusion substrate.
- the encapsulation film reinforces the edge region of the MEA and can also seal the edge region of the MEA if the adhesive film impregnates through the thickness of the gas diffusion substrate.
- the MEAs may be incorporated into fuel cell stacks using standard stack assembly techniques whereby the MEAs are interposed between flow field plates and the stack is compressed using a piston system or a series of bolts located in the stack end plates.
- WO 2005/101554 discloses a method of bonding MEAs to flow field plates wherein an adhesive material is in contact with protective film layers attached to the MEA. The adhesive material is not in contact with the ionoraer membrane or the electrode layers and this is said to reduce contamination of the membrane and electrode layers.
- Multi-layer MEAs comprising an MEA and two flow field plates are assembled into stacks using standard stack assembly processes.
- the present inventors have sought to provide fuel cell components that retain the technical advantages of known MEAs, such as edge reinforcement and edge sealing, yet can be assembled into a stack in a simplified and more reliable process.
- the present invention provides an assembly for use in a fuel cell, comprising an ion-conducting membrane, first and second electrocatalyst layers disposed either side of the membrane, first and second gas diffusion substrates contacting the first and second electrocatalyst layers respectively, and a first flow field plate contacting the first gas diffusion substrate, wherein a first encapsulation film, comprising a backing layer and an adhesive layer, is positioned between edge regions of the membrane and the first gas diffusion substrate such that the adhesive layer impregnates through the thickness of the first gas diffusion substrate, and characterised in that the adhesive layer bonds the first flow field plate to the first gas diffusion layer, thereby unitising the assembly.
- a first encapsulation film comprising a backing layer and an adhesive layer
- the assembly of the invention comprises at least one MEA and at least one flow field plate that are unitised and may be handled as a single component.
- the simplest embodiment of the invention is essentially a six-layer assembly (one membrane, two electrocatalyst layers, two gas diffusion substrates and a flow field plate). If the assembly is a six-layer assembly, consisting of just one MEA and just one flow field plate, then the flow field plate is preferably a bipolar flow field plate.
- a multiplicity of six-layer assemblies, each consisting of one MEA and one bipolar flow field plate, may be further assembled into a fuel cell stack, and the only additional component that is required is a single stack end plate.
- the assembly of the invention may further comprise a second flow field plate that contacts the second gas diffusion substrate, and a second encapsulation film, comprising a backing layer and an adhesive layer, wherein the second encapsulation fihn is positioned between edge regions of the membrane and the second gas diffusion substrate such that the adhesive layer impregnates through the thickness of the second gas diffusion substrate, and wherein the adhesive layer bonds the second flow field plate to the second gas diffusion layer.
- Another simple embodiment of the invention is essentially a seven-layer assembly (one membrane, two electrocatalyst layers, two gas diffusion substrates and two flow field plates). If the assembly is a seven-layer assembly, consisting of one MEA and two flow field plates, then the flow field plates are preferably monopolar flow field plates. A multiplicity of seven-layer assemblies, each consisting of one MEA and two monopolar flow field plates, may be further assembled into a fuel cell stack.
- the assembly of the invention may further comprise a second ion-conducting membrane, third and fourth electrocatalyst layers disposed either side of the second membrane, third and fourth gas diffusion substrates contacting the third and fourth electrocatalyst layers respectively, wherein a third encapsulation film, comprising a backing layer and an adhesive layer, is positioned between edge regions of the second membrane and the third gas diffusion substrate such that the adhesive layer impregnates through the thickness of the third gas diffusion substrate, and wherein the adhesive layer bonds the second flow field plate to the third gas diffusion layer.
- a third encapsulation film comprising a backing layer and an adhesive layer
- An embodiment of the invention is essentially a twelve-layer assembly (two membranes, four electrocatalyst layers, four gas diffusion substrates and two flow field plates). If the assembly is a twelve-layer assembly consisting of two MEAs and two flow field plates, then the flow field plates are preferably bipolar flow field plates. A multiplicity of twelve-layer assemblies, each consisting of two MEAs and two bipolar flow field plates, may be further assembled into a fuel cell stack, and the only additional component that is required is a single stack end plate.
- the invention has thus far been described by reference to a six-layer assembly (one MEA and one flow field plate), a seven-layer assembly (one MEA and two flow field plates) and a twelve-layer assembly (two MEAs and two flow field plates).
- Assemblies comprising further MEAs and flow field plates are within the scope of the present invention, e.g. a thirteen-layer assembly (two MEAs and three flow field plates) and an eighteen-layer assembly (three MEAs and three flow field plates).
- each MEA is unitised with an adjacent flow field plate by means of an encapsulation film, comprising a backing layer and an adhesive layer, which is positioned between edge regions of the membrane and the diffusion substrate such that the adhesive layer impregnates through the thickness of the gas diffusion substrate, and wherein the adhesive layer bonds the flow field plate to the gas diffusion layer.
- the assembly consists of n ion-conducting membranes, 2n electrocatalyst layers, 2n gas diffusion substrates and n or n+1 flow field plates, wherein n is from 2 to 10, preferably from 3 to 6.
- first encapsulation film first gas diffusion substrate, first electrocatalyst layer and the first flow field plate, but these features apply equally to the additional encapsulation films, gas diffusion substrates, electrocatalyst layers and the flow field plates.
- the unitised fuel cell assembly of the present invention comprising at least one MEA and at least one flow field plate can advantageously be used to assemble fuel cell stacks.
- the part count in the stack assembly is reduced and alignment of the components is much easier.
- the assemblies of the invention are more robust than individual MEAs and flow field plates, reducing the potential for damage to components during stack assembly. If the components fail whilst in the fuel cell stack, it is straightforward to remove and replace the faulty component.
- Assemblies having n+1 flow field plates wherein the number of membranes is n can be prepared as a gas-tight module, obviating the need for further seals. This assembly can be tested for gas leakage, electrical shorts and gas crossover prior to stack building, reducing the likelihood of failure whilst in the fuel cell stack.
- the first encapsulation film is positioned between edge regions of the membrane and the first gas diffusion substrate. If the MEA has internal porting, there may be edge regions within the assembly and not just around the periphery. Suitably the first encapsulation film covers a region that is within less than 15mm of the edge of the first gas diffusion substrate, preferably less than 8rnm.
- the first encapsulation film has a backing layer which is suitably a nonconducting self-supporting filrn material.
- the backing layer does not impregnate the first gas diffusion substrate, and suitably contacts the first gas diffusion substrate.
- the backing layer is non-adhesive.
- the melting temperature of the backing layer must be higher than the temperatures used when manufacturing the assembly (e.g. lamination temperatures), and preferably the backing layer shows no appreciable film softening at the manufacturing temperatures.
- the backing layer does not shrink appreciably under the manufacturing conditions.
- the backing layer is suitably made of a material that does not leach contaminants into the fuel cell system, and that has low permeability to hydrogen, oxygen and water (suitably lower than the permeability of the polymer electrolyte membrane). Additionally, the material of the backing layer is preferably resistant to puncture by fibres from the gas diffusion substrate.
- the backing layer is preferably a polymeric material such as polyethylene terephthalate (PET), polyvinylidene fluoride (PVDF), ethylene-vinyl alcohol (EVOH), biaxiaUy-oriented polypropylene (BOPP), polytetrafluoro ethylene (PTFE), ethylene tetrafluoroethylene (ETFE), polyether sulphone (PES), polyether ether ketone (PEEK), fluormated ethylene-propylene (FEP), polyphenylene sulphide (PPS) or polyimide (PI).
- PET polyethylene terephthalate
- PVDF polyvinylidene fluoride
- EVOH ethylene-vinyl alcohol
- BOPP biaxiaUy-oriented polypropylene
- PTFE polytetrafluoro ethylene
- ETFE ethylene tetrafluoroethylene
- EES polyether sulphone
- PEEK polyether ether ketone
- FEP fluormated
- the first encapsulation film has an adhesive layer which is, for example, a polyethylene-based or polypropylene-based adhesive.
- the adhesive layer may contain a hot-melt adhesive, a pressure-sensitive adhesive or a thermosetting adhesive.
- the adhesive may be a copolymer of ethylene and methacrylic acid or a copolymer of ethylene and vinyl acetate, as described in US 6,756,147.
- the adhesive must be sufficiently fluid to impregnate the substrate.
- the adhesive layer does not shrink appreciably under manufacturing conditions.
- the adhesive layer is made of a material that does not leach contaminants into the fuel cell system.
- the adhesive layer must be sufficiently thick to impregnate through the first gas diffusion substrate and bond to the first flow field plate.
- the first encapsulation film has only one adhesive layer and this layer impregnates through the thickness of the first gas diffusion substrate.
- the backing layer directly contacts the membrane (or a catalyst-coated region of membrane) and there is no adhesion between the first encapsulation film and the membrane.
- the thickness of the backing film is the same as the thickness of the first electrocatalyst layer to prevent contact losses.
- the first encapsulation film has two adhesive layers, so that a first adhesive layer impregnates through the thickness of the first gas diffusion substrate, and a second adhesive layer adheres to the membrane.
- a first adhesive layer impregnates through the thickness of the first gas diffusion substrate, and a second adhesive layer adheres to the membrane.
- the thickness of the second adhesive layer is less than the thickness of the first adhesive layer.
- the thickness of the second adhesive layer is between 0.1 and 20 ⁇ m thick, more preferably between 1-1 O ⁇ m thick.
- the combined thickness of the backing layer and the second adhesive layer is the same as the thickness of the first electro catalyst layer.
- the first and second adhesive layers may contain the same or different adhesives.
- the gas diffusion substrates may be any suitable gas diffusion substrates known to those skilled in the art.
- Typical substrates include substrates based on carbon paper
- the carbon substrate is typically modified with a particulate material either embedded within the substrate or coated onto the planar faces, or a combination of both.
- the particulate material is typically a mixture of carbon black and a polymer such as ' polytetrafluoroethylene (PTFE).
- PTFE polytetrafluoroethylene
- the gas diffusion substrates are between 100 and 300 ⁇ m thick.
- the ion-conducting membrane may be any type of ion-conducting membrane known to those skilled in the art.
- the membrane is proton-conducting.
- the membranes are often based on perfluorinated sulphonic acid materials such as Nafion® (DuPont), Flemion® (Asahi).
- the membrane may be a composite membrane, containing the proton-conducting material and other materials that confer properties such as mechanical strength.
- the membrane may comprise a proton-conducting membrane and a matrix of silica fibres, as described in EP 875 524.
- the membrane is suitably less than 200 ⁇ m thick, preferably less than 50 ⁇ m thick.
- the electrocatalyst layers comprise an electrocatalyst which may be a finely divided metal powder (metal black), or may be a supported catalyst wherein small metal particles are dispersed on electrically conducting particulate carbon supports.
- the electrocatalyst metal is suitably selected from (i) the platinum group metals (platinum, palladium, rhodium, ruthenium, iridium and osmium), (ii) gold or silver,
- a base metal or an alloy or mixture comprising one or more of these metals or their oxides.
- the preferred electrocatalyst metal is platinum, which may be alloyed with other precious metals such as ruthenium, or base metals such as cobalt, molybdenum or tungsten. If the electrocatalyst is a supported catalyst, the loading of metal particles on the carbon support material is suitably in the range 10-100wt%, preferably 15-75wt%.
- the electrocatalyst layers suitably comprise other components, such as ion- conducting polymer, which is included to improve the ionic conductivity within the layer.
- the layers can be formed on the gas diffusion substrates, or the layers can be formed on the membrane.
- the flow field plates are suitably conventional flow field plates known to those skilled in the art. They are typically made from materials such as graphite, graphite/polymer composites, metals or metal composite materials.
- the first encapsulation film is positioned between edge regions of the membrane and the first gas diffusion substrate such that the adhesive layer impregnates through the thickness of the first gas diffusion substrate.
- the first electrocatalyst layer may or may not be present at the edge regions of the membrane and the first gas diffusion substrate. It is preferred that the first electrocatalyst layer is present at the edge regions of the membrane and the first gas diffusion substrate such that the first encapsulation firm contacts the edge region of the first electrocatalyst layer.
- the backing layer of the first encapsulation film can either be between the membrane and the edge region of the first electrocatalyst layer or between the first gas diffusion substrate and the edge region of the first electrocatalyst layer.
- any electrocatalyst in this region will be outside the electrochemically active area of the MEA and will not be able to take part in the electrochemical reactions, but overlapping the edge region of the first electrocatalyst layer and the first encapsulation film can improve MEA durability.
- the assembly of the invention may be assembled from its component parts in one or more lamination steps. It is preferred that the membrane, electrocatalyst layer(s), gas diffusion substrate(s) and encapsulation film(s) are combined using, e.g. the methods disclosed in WO 2005/020356, and are subsequently combined with flow field plate(s) in a further hot pressing step. The pressure and temperature must be sufficient to adhere the adhesive layer(s) to the flow field plate(s).
- the present invention further provides a fuel cell stack comprising more than one assembly according to the invention.
- the assemblies of the invention may be assembled into a fuel cell stack by a method wherein several assemblies are stacked together.
- the assemblies may be adhered to one another using an adhesive, or they may be mechanically joined, e.g. using bolts.
- an assembly according to the invention comprising e.g. 4 to 10 MEAs may provide the entire fuel cell stack.
- Fig. 1 is a schematic diagram showing a method of preparing an assembly according to an embodiment of the invention.
- Fig. 2 is a schematic diagram showing a method of preparing an assembly according to an embodiment of the invention.
- Fig. 3 is a schematic diagram showing how assemblies according to embodiments of the invention can be assembled into fuel cell stacks.
- Step (i) of Fig. 1 shows encapsulation films comprising backing layers (5) and adhesive layers (4) positioned on the edges of the inner faces of gas diffusion electrodes comprising substrates (2) and electrocatalyst layers (3).
- the encapsulation films are hot pressed (6) at the positions shown by arrows and the adhesive layers (4) impregnate through the thickness of the gas diffusion substrates (2).
- a membrane (1) is positioned between the gas diffusion electrodes (2, 3). The membrane (1) extends beyond the gas diffusion substrates (2).
- step (iii) the gas diffusion electrodes (2, 3) axe laminated to the membrane (1) by hot pressing (6) at the positions shown by arrows.
- monopolar flow field plates (7) are laminated to the gas diffusion substrates (2) by hot pressing (6) at the positions shown by arrows.
- Step (i) of Fig. 2 shows a membrane (1), catalyst layers (3) on each face of the membrane, and two gas diffusion substrates (2).
- Encapsulation films comprising backing layers (5), first adhesive layers (4) and second adhesive layers (8) are positioned on the edges of the inner faces of the substrates (2).
- the encapsulation films are hot pressed (6) at the positions shown by arrows.
- the gas diffusion substrates (2) are laminated to the catalyst- coated membrane (I 5 3), the first adhesive layers (4) impregnate through the thickness of the gas diffusion substrates (2) and the second adhesive layers (8) adhere to the membrane.
- the encapsulation films extend beyond the edge of the membrane, and the region between the backing layers (5) is filled by adhesive.
- step (iii) bipolar flow field plates (7), a monopolar flow field plate (9) and membrane electrode assemblies are by hot pressed (6) at the positions shown by arrows.
- step (iv) shows the final assembly comprising three MEAs and four flow field plates.
- Figure 3a shows an assembly (10) comprising an MEA and two monopolar flow field plates. Six of these assemblies can be compiled to provide the fuel cell stack shown as (11).
- Figure 3b shows an assembly (12) comprising two MEAs and two bipolar flow field plates. Two of these assemblies and one stack end plate (13) can be used to provide the fuel cell stack shown as (14).
- Figure 3c shows an assembly (15) comprising three MEAs and four flow field plates (the plates within the assembly are bipolar plates whereas the plates on the exterior of the assembly are monopolar plates). Two of these assemblies can be used to provide the fuel cell stack shown as (16).
- the fuel cell stacks (11, 14, 16) have a smaller number of MEAs than is usual in practice, but the skilled person will appreciate that additional assemblies can be combined to form larger stacks.
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Abstract
L'invention concerne un ensemble pour une pile à combustible, ledit ensemble comprenant une membrane conductrice d'ions, des première et deuxième couches de photocatalyseur disposés de part et d'autre de la membrane, des premier et deuxième substrats de diffusion de gaz respectivement placés au contact des première et deuxième couches de photocatalyseur, et une première plaque à champ de propagation de flux placée au contact du premier substrat de diffusion de gaz. Une premier pellicule d'enrobage comprenant une couche support et une couche d'adhésif est placée entre des régions de bord de la membrane et le premier substrat de diffusion de gaz de façon à ce que la couche d'adhésif imprègne l'épaisseur du premier substrat de diffusion de gaz et colle la première plaque à champ de propagation de flux sur le premier substrat de diffusion de gaz pour solidariser ainsi l'ensemble.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB0606435.6A GB0606435D0 (en) | 2006-03-31 | 2006-03-31 | Assembly for use in a fuel cell |
GB0606435.6 | 2006-03-31 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007113592A1 true WO2007113592A1 (fr) | 2007-10-11 |
Family
ID=36424934
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB2007/050167 WO2007113592A1 (fr) | 2006-03-31 | 2007-03-29 | Ensemble pour pile a combustible |
Country Status (2)
Country | Link |
---|---|
GB (1) | GB0606435D0 (fr) |
WO (1) | WO2007113592A1 (fr) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2056382A2 (fr) | 2007-11-01 | 2009-05-06 | Honeywell International Inc. | Procédé de formation d'un bloc de pile à combustible |
US8399145B2 (en) | 2007-09-25 | 2013-03-19 | Johnson Matthey Fuel Cells Limited | Membrane electrode assembly |
GB2555126A (en) * | 2016-10-19 | 2018-04-25 | Univ Cape Town | A method of securing a gas diffusion layer to a catalyst coated membrane |
BE1027329B1 (fr) * | 2018-11-23 | 2021-04-08 | Hyet Holding B V | Compresseur a etat solide |
WO2022084121A1 (fr) * | 2020-10-19 | 2022-04-28 | Robert Bosch Gmbh | Unité membrane-électrode destinée à une cellule électrochimique, et procédé de fabrication d'une unité membrane-électrode |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
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WO2000026975A1 (fr) * | 1998-10-30 | 2000-05-11 | International Fuel Cells, Llc | Ensemble electrodes a membrane ameliore pour pile a combustible a membrane echangeuse de protons |
US6495278B1 (en) * | 1997-03-29 | 2002-12-17 | Ballard Power Systems Inc. | Polymer electrolyte membrane electrochemical fuel cells and stacks with adhesively bonded layers |
JP2003068332A (ja) * | 2001-06-15 | 2003-03-07 | Nok Corp | 燃料電池用構成部品 |
WO2005020356A1 (fr) * | 2003-08-22 | 2005-03-03 | Johnson Matthey Public Limited Company | Scellage d'un ensemble d'electrodes a membrane |
EP1624515A1 (fr) * | 2004-05-28 | 2006-02-08 | Du Pont Canada Inc. | Sous-ensemble d'une pile à combustible monobloc et méthode pour sa fabrication |
-
2006
- 2006-03-31 GB GBGB0606435.6A patent/GB0606435D0/en not_active Ceased
-
2007
- 2007-03-29 WO PCT/GB2007/050167 patent/WO2007113592A1/fr active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6495278B1 (en) * | 1997-03-29 | 2002-12-17 | Ballard Power Systems Inc. | Polymer electrolyte membrane electrochemical fuel cells and stacks with adhesively bonded layers |
WO2000026975A1 (fr) * | 1998-10-30 | 2000-05-11 | International Fuel Cells, Llc | Ensemble electrodes a membrane ameliore pour pile a combustible a membrane echangeuse de protons |
JP2003068332A (ja) * | 2001-06-15 | 2003-03-07 | Nok Corp | 燃料電池用構成部品 |
WO2005020356A1 (fr) * | 2003-08-22 | 2005-03-03 | Johnson Matthey Public Limited Company | Scellage d'un ensemble d'electrodes a membrane |
EP1624515A1 (fr) * | 2004-05-28 | 2006-02-08 | Du Pont Canada Inc. | Sous-ensemble d'une pile à combustible monobloc et méthode pour sa fabrication |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8399145B2 (en) | 2007-09-25 | 2013-03-19 | Johnson Matthey Fuel Cells Limited | Membrane electrode assembly |
EP2056382A2 (fr) | 2007-11-01 | 2009-05-06 | Honeywell International Inc. | Procédé de formation d'un bloc de pile à combustible |
EP2056382A3 (fr) * | 2007-11-01 | 2012-07-25 | Honeywell International Inc. | Procédé de formation d'un bloc de pile à combustible |
US9029038B2 (en) | 2007-11-01 | 2015-05-12 | Honeywell International Inc. | Method of forming a fuel cell stack |
US9225027B2 (en) | 2007-11-01 | 2015-12-29 | Honeywell International Inc. | Method of forming a fuel cell stack |
GB2555126A (en) * | 2016-10-19 | 2018-04-25 | Univ Cape Town | A method of securing a gas diffusion layer to a catalyst coated membrane |
GB2555126B (en) * | 2016-10-19 | 2019-05-15 | Univ Cape Town | A method of securing a gas diffusion layer to a catalyst coated membrane |
BE1027329B1 (fr) * | 2018-11-23 | 2021-04-08 | Hyet Holding B V | Compresseur a etat solide |
WO2022084121A1 (fr) * | 2020-10-19 | 2022-04-28 | Robert Bosch Gmbh | Unité membrane-électrode destinée à une cellule électrochimique, et procédé de fabrication d'une unité membrane-électrode |
Also Published As
Publication number | Publication date |
---|---|
GB0606435D0 (en) | 2006-05-10 |
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