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
  • H01M8/02—Details
  • H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
• • 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
  • H01M8/2404—Processes or apparatus for grouping fuel cells
• • 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
  • H01M8/2418—Grouping by arranging unit cells in a plane
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2300/00—Electrolytes
  • H01M2300/0017—Non-aqueous electrolytes
  • H01M2300/0065—Solid electrolytes
  • H01M2300/0082—Organic polymers
• • 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
  • H01M8/249—Grouping of fuel cells, e.g. stacking of fuel cells comprising two or more groupings of fuel cells, e.g. modular assemblies
• • 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
• • 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
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
  • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

• the invention relates to all installations for producing energy by means of fuel cells. It applies both to local or centralized production and to land, space or maritime transport.
• the power scale of such fuel cells is very wide, since it includes mobile or portable equipment producing a few milliwatts and static installations producing a power of several kilowatts.
• Fuel cells are electrochemical cells made up of a stack of stages, producing electricity. Each of them comprises an anode and a cathode each placed on either side of an electrolytic element. A different reagent arrives on each outer surface of the two electrodes, namely a fuel and an oxidizer. These react chemically via the electrolytic element, so that it is possible to take an electrical voltage, of the order of 1 volt, at zero current, across the terminals of the two electrodes. If the fuel is hydrogen and the oxidizer oxygen, hydrogen oxidation takes place at the anode, while at the cathode the reduction of oxygen to water occurs. The low voltage produced is the main handicap of the fuel cell system compared to conventional batteries, whose elementary voltage can rise up to 4 volts. To remedy this problem, it is customary to constitute fuel cells constructed by a stack of a large number of basic elements or stages producing electricity, according to a technology which can be called “filter- hurry ".
• Such a fuel cell therefore consists of a stack of a large number of stages.
• Each stage itself consists of a basic element consisting of a membrane / electrode assembly 2 comprising a membrane and two electrodes and of the two halves of two bipolar plates 3 each placed between the two basic membrane / electrode elements 2 of two consecutive floors.
• At least one manifold 4A supplies each stage with hydrogen and at least one manifold 4B supplies each stage with oxygen.
• Collectors for discharging products from the redox are also provided at the periphery of this stack, but are not shown in this figure 1. The entire stack is kept clamped between two end plates 1.
• a fuel cell is known using a membrane / electrode base element of a particular type. Indeed, it consists of an assembly of several membrane / electrode basic elements, that is to say of several individual batteries 10, placed one next to or behind the other, an anode 11 and a cathode 12, enclosing an electrolytic layer 13. These individual cells 11 are separated by insulating zones 17, but are connected together by a piece conductive 14. In fact, a first end 15 of this conductive part 14 is connected to the cathode 12 of a first battery 10, while a second end 16 of this conductive part 14 is connected to the anode 11 of the battery 10 which is adjacent to it.
• the main object of the invention is therefore to remedy these drawbacks, by proposing a method of manufacturing an assembly of membrane / electrode basic elements of fuel cells, comprising several elementary cells, and which can be carried out in series. , reliably, avoiding machining and which can make it possible to achieve optimum sealing between such assemblies of membrane elements / electrodes and their bipolar plates.
• the main object of the invention is a method of manufacturing a assembly of anode / membrane / cathode base elements of a fuel cell stage and consisting of a plurality of anode / membrane / cathode base elements, electrically connected to each other by an electronic conductor connecting the anode from a base element to the cathode of the adjacent base element.
• the assembly therefore includes:
• the method mainly consists in using as support a plate of weft material in which and on which are deposited the materials constituting the various elements of the assembly and in depositing a layer of seal over the entire thickness of the plate and pairs of vertical insulating walls to delimit the different elementary stacks or basic elements.
• the first operation therefore consists in cutting, to the desired shape, a piece of sheet of weft material.
• this can be made of a porous matrix, made of Teflon or glass.
• the third operation is preferably the deposition of the ionic conductor inside the plate, but not between the two vertical walls intended to delimit the elementary cells.
• the fourth operation is, in this case, the deposition of the electronic conductor between the two vertical insulating walls of all the couples.
• the following operation consists in depositing the anodes on a first surface of the plate thus filled and the cathodes on the other surface of this same plate.
• An electronic collector is placed on one of the two ends of the series of anodes and cathodes, in an opposite manner.
• FIG. 3 therefore represents the assembly of basic elements according to the invention, once completed.
• All the functional elements of this assembly are parts deposited one after the other on and / or in a plate of weft material whose thickness corresponds to the thickness of the ion conductor layer.
• the assembly comprises, first of all, a peripheral seal 21, placed over the entire thickness of the plate at the periphery thereof.
• a chemically inert material which is electronically and ionically insulating is chosen.
• the different elementary cells of this assembly each consist of an anode 22 placed on a first surface of the plate, a cathode 23 placed on the opposite surface of the plate and a deposit of ionic conductor 24 placed between the anode 22 and the cathode 23, over the entire thickness of the plate. Note that the anode protrudes from one side of the ion conductor 24 and that the cathode 23 protrudes from
• each projecting part of the anodes 22 and of the cathodes 23 is located opposite, to the thickness of the plate near, a cathode 23 or an anode 22 of a neighboring cell, except for the anode 22 of a first end cell and cathode 23 of the other end cell.
• This special protruding arrangement of the anodes 22 and the cathodes 23 allows an electronic conductor 26, deposited throughout the thickness of the plate, to connect the anode 22 of a stack of rows n to the cathode 23 of the stack next to the rank n + 1, which is placed opposite it.
• Two vertical insulating seal layers are used to connect the anode 22 of a stack of rows n to the cathode 23 of the stack next to the rank n + 1, which is placed opposite it.
• An electronic collector 26 is placed on the anode 22 projecting from a first end stack and on the cathode 23 projecting from the other end stack.
• the assembly according to the invention forms a homogeneous one-piece assembly impermeable to gas.
• FIG. 4 shows an embodiment of the plate of weft material in the form of a porous matrix 20.
• the shape of this porous matrix 20 is directly linked to the application of the fuel cell for which it is intended and to the space available. Different forms are therefore envisaged, ranging from the prismatic cell to the spiral cylinder, passing through a simple sheet or a tube.
• the thickness of the porous matrix determines the thickness of the assembly of basic elements, produced in this porous matrix. Cleaning or chemical treatment may also be necessary depending on the different applications that must be made of the assembly and the material constituting the porous matrix.
• porous teflon and porous glass can advantageously be used to constitute this porous matrix 20.
• FIG. 5 shows the first phase of deposition of material on and in the porous matrix 20.
• This peripheral seal 21 has a thickness slightly greater than the thickness of the plate 20 so that it can be very slightly compressed.
• This step is completed by the deposition of several series of two vertical and parallel insulating walls 25 intended to delimit and isolate the areas of the plate 20 which will subsequently be filled with ionic deposition. A slight space remains between each pair of vertical insulating walls 25 to allow another subsequent deposition of an electronic conductor.
• Each insulating wall 25 crosses the entire thickness of the porous matrix 20 and exceeds one of the two surfaces of the latter, so that each insulating wall 25 also separates two anodes or two cathodes. All these deposits are made using masks placed on the parts of the two surfaces of the porous matrix which must not receive the material to be deposited.
• FIG. 6 shows a second deposit of material, which is that of the ionic conductor.
• the ionic conductor deposits 24 relate to the zones delimited by the pairs of insulating vertical walls 25 and the peripheral seal 21 at this same end. These deposits of ionic conductors 24 therefore take place over the entire thickness of the porous matrix 20.
• FIG. 7 shows the filling of the spaces located between two vertical insulating walls 25 of the same pair, by means of an electronic conductive material 26, and over the entire thickness of the porous matrix 20, in the same way as the conductor deposit ionic 24.
• the material used can be a mixture of joint material and a material containing a conductive filler, such as graphite, carbon or metal.
• the last phase consists in depositing the electrodes, that is to say the anodes 22 and the cathodes 23 and adding an electronic collector 26 to each end of the assembly.
• the anodes 22 and cathodes 23 are deposited in such a way that each catalytic layer deposited and constituting one of these electrodes protrudes with respect to one side of the opposite ion conductor layer 24 which exceeds the vertical insulating wall 25, to be in intimate contact with the deposit of conductive material 26 located between these two vertical insulating walls 25.
• each layer constituting these anodes 22 and cathodes 23 may be only a few microns.
• a collector 27 is placed on the anode 22N protruding from a first end of the assembly, while another electrical collector 27 is placed on the protruding part of the last cathode 23N of the assembly, on the other face of the porous matrix. The latter is thus completely filled and is completely covered, except at the level of the peripheral seal 21.
• the method according to the invention does not implement any machining and is relatively simple, since it only uses material deposition methods with the possible intervention of masks. It is necessary to take into account the fact of the nature of the matrix, which is here porous, but which could be of mat type or fabric.
• FIG. 8 illustrates an example of stacking made for the construction of a fuel cell where each stage uses an assembly of basic elements as just described.
• the complementary constituent elements are bipolar plates 30, each placed between two assemblies marked 40, corresponding to the thickness of the porous matrix 20, increased by the compressed additional thickness of the peripheral seal 21.
• a circuit of fuel collectors 41 is installed on the sides of the stack to supply both oxidizer and fuel, such as air and hydrogen, to each bipolar plate.
• oxidizer and fuel such as air and hydrogen
• the bipolar plates 30 must then be electronically insulating and constitute a gas-tight barrier. Common plastic materials, for example of the polysulfone, polyethylene or teflon type, can be used.
• weft material plates can, perhaps, be used. This allows to be able to build fuel cells of any section, depending on the space available to them.
• the method of manufacturing such an assembly of basic elements does not involve complicated and costly machining, but only uses deposition methods.
• This assembly structure of basic elements can be used both for batteries operating at high or low temperature.
• the number of basic elements or basic cells constituting each assembly can also be a function of the voltage which it is desired to obtain with the fuel cell constituted with a series of assemblies. All applications are possible for such a fuel cell, but light, portable systems requiring electrical supplies with a voltage greater than 1 volt and in which the weight and shape problems arise, constitute a preferred application.
• the fuel feeding a cell can be stored in the form of compressed gas outside the cell or else in the form adsorbed in hydrides, which can be produced in the form of hydride sheets in contact with the anodes.

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• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Fuel Cell (AREA)

Applications Claiming Priority (3)

Publications (1)

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ID=8858390

Family Applications (1)

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• 2000
  • 2000-12-29 FR FR0017279A patent/FR2819107B1/fr not_active Expired - Fee Related
• 2001
  • 2001-12-28 EP EP01989671A patent/EP1356536A1/de not_active Withdrawn
  • 2001-12-28 JP JP2002554907A patent/JP2004517446A/ja not_active Withdrawn
  • 2001-12-28 WO PCT/FR2001/004221 patent/WO2002054522A1/fr active Application Filing
  • 2001-12-28 US US10/451,169 patent/US20040071865A1/en not_active Abandoned

Non-Patent Citations (1)

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