US20040265653A1 - Method and apparatus for humidification of the membrane of a fuel cell - Google Patents
Method and apparatus for humidification of the membrane of a fuel cell Download PDFInfo
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- US20040265653A1 US20040265653A1 US10/608,088 US60808803A US2004265653A1 US 20040265653 A1 US20040265653 A1 US 20040265653A1 US 60808803 A US60808803 A US 60808803A US 2004265653 A1 US2004265653 A1 US 2004265653A1
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- fuel cells
- humidity
- membrane
- fuel
- fuel cell
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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
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
- H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
- H01M8/04119—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants with simultaneous supply or evacuation of electrolyte; Humidifying or dehumidifying
- H01M8/04126—Humidifying
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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
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
- H01M8/0263—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant having meandering or serpentine paths
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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
- H01M8/0267—Collectors; Separators, e.g. bipolar separators; Interconnectors having heating or cooling means, e.g. heaters or coolant flow channels
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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
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
- H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
- H01M8/04119—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants with simultaneous supply or evacuation of electrolyte; Humidifying or dehumidifying
- H01M8/04126—Humidifying
- H01M8/04141—Humidifying by water containing exhaust gases
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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
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
- H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
- H01M8/04119—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants with simultaneous supply or evacuation of electrolyte; Humidifying or dehumidifying
- H01M8/04126—Humidifying
- H01M8/04149—Humidifying by diffusion, e.g. making use of membranes
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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
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04291—Arrangements for managing water in solid electrolyte fuel cell systems
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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
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/2465—Details of groupings of fuel cells
- H01M8/2483—Details of groupings of fuel cells characterised by internal manifolds
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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 method and an apparatus for exchanging humidity between the fuels in a fuel cell.
- a fuel cell has a stack-like structure with an electrolyte arranged between end plates. Between the electrolyte and one end plate is an anode, and between the electrolyte and the other end plate is a cathode.
- Solid and liquid electrolytes are known; as the case may be, the electrolyte can be absorbed by a carrier structure or itself possesses the requisite solidity enabling it to be used in the cell.
- the operating temperatures also differ considerably and vary from ambient temperature to several hundred degrees C. and above.
- a polymer electrolyte membrane (PEM) is used in the fuel cell.
- the fuel cell is then supplied on the anode side with e.g. hydrogen in gaseous form and on the cathode side with e.g. ambient air containing oxygen.
- the hydrogen and oxygen are used here by way of a non-limiting example.
- reaction partners which participate in the chemical reaction in a fuel cell are designated as fuels, as are their carrier fluids (e.g. ambient air as a carrier fluid for the reaction partner O 2 ).
- carrier fluids e.g. ambient air as a carrier fluid for the reaction partner O 2 .
- the fuels are present in fluid form.
- a catalytic converter e.g. platinum
- the protons are transported in the membrane in the form of H 3 O + ions; this is dependent upon the appropriate water content of the membrane. With a higher water content the ability of the membrane to conduct protons improves.
- the degree of operationally necessary humidity is therefore predetermined by the person skilled in the art, taking into account the parameters of the fuel cell and characteristics of the membrane.
- the membrane continuously loses humidity, since as stated above, the protons are transported through the membrane via H 3 O + ions. Furthermore, water is produced on the cathode side. In this way the air flow on the cathode side continuously becomes charged with humidity on its route across the membrane. In the area of the inlet, the air flow which is not as yet charged with humidity helps the membrane to dry out, while in the area of the outlet it tends to have excess humidity (condensation).
- the membrane is too dry on the inlet side, which as mentioned above is undesirable. If a fuel cell stack continues to be operated, the overly dry parts of the membrane of a fuel cell generate resistance via a corresponding production of heat, which, in turn, accelerates the drying out process. This leads to a significant reduction in cell output, overheating, and even destruction of the affected cell.
- Humidity refers not only to the presence of water.
- fluids such as protons in the case of PEM membranes
- humidity refers to any substance which in the case of a given membrane (and given fuels) permits charges (such as protons in the case of PEM membranes) to be transported through the membrane.
- U.S. Pat. No. 4,973,530 discloses a method for regulating the humidity content in a fuel cell membrane by continuous addition of externally supplied water into the anode area and by continuous removal of humidity on the cathode side.
- a further membrane which is pervious to water is arranged next to the membrane of the fuel cell and the channel for the hydrogen is arranged in such an alternating pattern that it is routed back and forth in a zigzag fashion first via the membrane of the fuel cell, then via the water-pervious membrane, until both membranes are fully covered and the residual hydrogen can be expelled to the outside.
- a further, also water-pervious membrane is used to remove humidity from the cathode area with the same zigzag routing arrangement, in that a dry gas is routed over the further membrane, absorbs the humidity to be discharged, and expels it to the outside.
- the present invention relates to a system and method for humidity management in a fuel cell.
- the present invention is advantageous because humidity is removed from the fluid flow expelled from the cathode area and is added to the fluid flow which flows into the cathode area, a simple humidity circuit is produced which can be achieved without any greater construction effort and in particular does not require any further external gas or water circuits, as is the case in the above-cited prior art.
- Sufficient humidity needs only to be added to the fluid flowing into the cathode area as is necessary to keep the cathode-side inlet area of the electrolyte membrane above a critical humidity. Excess humidity can be expelled to the outside with the outflowing fluid.
- the cathode area and the anode area may be dehumidified.
- a stack of fuel cells is formed from a plurality of fuel cells, it is customary to provide the individual fuel cells with common supply and discharge channels for the fuels, said channels running along or through the stack. Arrangements are preferred in which the supply and discharge channels terminate jointly at one end of the stack, the cathode-side connection of the respective fuel cell to the humidity exchanger associated therewith being kept separate from the same connections of adjacent fuel cells. Only the dehumidified fluid expelled from the humidity exchanger is fed back into the discharge channel common to all fuel cells.
- FIG. 1 depicts a fuel cell stack according to the prior art, in schematic form
- FIG. 2 depicts a cross-section through the stack in FIG. 1 in schematic form, with laterally routed fluid channels
- FIG. 3 depicts a fuel cell according to the present invention, in schematic form
- FIG. 4 depicts a cross-section through a part of a fuel cell stack according to the present invention, in schematic form.
- FIG. 1 depicts schematically and by way of example a stack 1 of fuel cells formed from two PEM fuel cells 1 a and 1 b .
- the fuel cell stack 1 may comprise many fuel cells, with stacks having approximately 100 fuel cells being common.
- the present invention may also be applied to other than PEM fuel cells.
- Each fuel cell 1 a , 1 b further comprises end plates 2 a , 2 b , with the adjacent end plates of the cells 1 a , 1 b here being combined to form a bipolar plate 3 .
- the fuel cells 1 a , 1 b of the stack 1 are constructed in the same way: between the end plates 2 a or 2 b and the bipolar plate 3 is a polymer electrolyte membrane 4 in each of the cells 1 a and 1 b .
- a polymer electrolyte membrane 4 in each of the cells 1 a and 1 b .
- an anode 5 or a cathode 6 is arranged on opposite sides of membrane 4 , i.e. on the side of the end plates 2 a or 2 b and on the side of the bipolar plate 3 .
- Channels 7 a , 7 b are used to supply gaseous fuels, in this case on the anode side H 2 , or a fluid containing H 2 (channels 7 a ) and on the cathode side O 2 or ambient air or another fluid containing O 2 (channels 7 b ). It is known in principle in the prior art for the channels 7 a and 7 b to be designed such that the transported fluids can be supplied as evenly as possible to the whole membrane surface.
- the collection channels 10 a and 10 b (running along the lateral surfaces 80 , 90 of the stack 1 ) for supplying (channels 10 a ) and discharging (channels 10 b ) fluid in the stack 1 are depicted in FIG. 2. They run along the sides of the stack and are connected with each of the fuel cells of the stack 1 via the respective channels 7 a and 7 b of the fuel cells.
- the collection channels 10 a and 10 b are open at one end, e.g. in the case of the first fuel cell of the stack 1 , and connected to the fluid supply unit of the stack, while the other end (in the case of the last fuel cell) is blind, i.e. closed.
- An electrical load 8 is connected to an anode 5 or a cathode 6 via a conductor 9 .
- FIG. 2 depicts in schematic form a cross-section through the fuel cell stack 1 at the location of a membrane 4 .
- the membrane 4 has a membrane body 13 , via which protons are transported.
- the membrane 4 has a sealing function at its edges: first of all the edge sections 14 seal off the gas supply channels and discharge channels 10 a and 10 b which, as mentioned, run along the stack and feed the channels 7 a and 7 b (FIG. 1). Also shown is the channel 10 c for the supply of coolant and a channel 10 d for discharge of the coolant, said channels also formed by edge sections 14 .
- the membrane 4 has sealing edge sections 15 for the edges of the end or bipolar plates 2 a , 2 b and 3 .
- the sections 14 and 15 prevent undesired contact of the various media (fuels, coolant and ambient air). Also shown are recesses 16 for tensile elements which hold the fuel cell stack 1 mechanically together.
- the layout shown in FIGS. 1 and 2 is known in principle to the person skilled in the art.
- Fluid supply (be it hydrogen or ambient air): at the inlet of the respective channel 10 a , 10 b high dynamic pressure, generated by the fluid pump 1 associated with the stack 1 , and correspondingly low static pressure; further back in the channel the dynamic pressure falls and the static pressure increases, until at the end of the channel (at the last fuel cell in stack 1 ) the dynamic pressure is at its lowest and the static pressure at its highest.
- the individual cells in the stack are thus fed with different pressures.
- FIG. 3 shows in schematic form an “exploded view” of a fuel cell 1 a or 1 b according to the present invention.
- the cell comprises a section A in which the electrochemical reaction for current generation takes place, and of a section B which is designed as a humidity exchanger; sections A and B are separated from one another by the operationally interacting webs 20 and 21 .
- section A includes an anode area 22 and a cathode area 23 .
- Section B includes a dehumidifying zone 24 and a humidifying zone 25 .
- the areas 22 and 23 and the zones 24 and 25 are separated from one another by the membrane 4 which extends through the whole cell 1 a , 1 b (see FIG. 1).
- the membrane may comprise a variety of materials.
- the channels 7 a run in the anode area 22 , and hydrogen flows through them in the direction of flow indicated by the arrows 32 and 33 , thereby covering the membrane 4 substantially evenly over the corresponding membrane section 26 .
- the channels 7 b for even transport of oxygen or ambient air ran across the other side of the membrane section 26 .
- ambient air enters section B of the cell 1 a , 1 b (arrow 30 ) via an inflow channel 28 .
- the route of the inflow channel 28 is depicted in simple form so as not to overcomplicate the figure; however, the person skilled in the art will provide a route which is suitable for covering the whole membrane section 27 evenly.
- the humidity exchanger is thus situated in the inflow channel 28 or the inflow line and in the outflow channel 29 or the outflow line for the fluid supplied and discharged on the cathode side.
- the sections A and B are separated from one another and sealed against fluid by the webs 20 , 21 , the membrane 4 also acting as part of the seal. Suitable sealing strategies are known to the person skilled in the art.
- the inflow channel 28 and the channel 7 b of the cathode area 23 are connected via a channel section 32 passing under the web 21 .
- the cathode area 23 and the outflow channel 29 are connected via an inner uptake channel 33 formed by an opening or eye 37 of the webs 20 , 21 , the connection being shown in more detail in FIG. 4.
- the uptake channel 33 has side walls 33 a and 33 b .
- the membrane 4 has a corresponding opening for the unobstructed passage of the transported gas at the location of the uptake channel 33 .
- the membrane 4 is, as a polymer electrolyte membrane, pervious to water. Accordingly, in section A H 3 O + ions from the anode area 22 can reach the cathode area 23 (via membrane section 26 ) and in section B water from the dehumidifying zone 24 can reach the humidifying zone 25 (via membrane section 27 ).
- water from the dehumidifying zone 24 can reach the humidifying zone 25 (via membrane section 27 ).
- membrane section A and for section B respectively, and made of a different material if necessary.
- the person skilled in the art will select such an arrangement depending on the type of fuel used, the operating temperature and the type of humidifying medium. The use of different membranes lies within the scope of the present invention.
- This arrangement allows freshly supplied ambient air from inflow channel 28 to pass membrane section 27 , pick up humidity, and then to pass under the web 21 via channel section 32 into channel 7 b , where it spreads along the membrane section 26 of the cathode area 23 , and because of its increased humidity, prevents the membrane area 34 , situated at the inlet of the channels 7 b , from drying out.
- the ambient air again picks up the humidity it loses in the membrane area 34 , and then passes through the uptake channel 33 into the dehumidifying zone 24 of section B, where in the outflow channel 29 it again loses a considerable part of its humidity, since this penetrates the membrane section 27 and is absorbed on the other side of the membrane 4 by the inflowing air.
- the required humidity is thus part of a simple circuit and need no longer be regularly supplied from the outside.
- the inflow and outflow of the fluid in the inflow channel 28 and outflow channel 29 have the same direction of flow, so that consequently the inflowing fluid is increasingly charged with humidity, and the fluid flowing in parallel loses humidity, until both (ideally) have the same humidity (namely half) compared to the original humidity differential. This “half” humidity value cannot be exceeded.
- an inflowing and outflowing fluid can be routed in the reverse flow through section B, with the consequence that the inflowing fluid is exposed on its route to section A to ever higher humidity of the outflowing fluid, since the humidity of the latter is greatest immediately after leaving section A.
- the inflowing fluid picks up more and more humidity on its mute to section A, the humidity of the fluid flowing on the other side of the membrane 4 also increases on this route, so that there is no limit on humidity to be transferred, as with parallel flow routing of the fluid.
- This arrangement is e.g. advantageous if sufficient surface area is available in the humidity exchanger.
- FIG. 4 shows a partial cross-section along the line A*-A* of FIG. 3 through a fuel cell stack 1 with three fuel cells n ⁇ 1, n and n+1.
- the cells n and n+1 may correspond to the cells 1 a and 1 b of FIG. 1.
- the ambient air route is shown out of the cathode area 23 into the outflow channel 29 of the dehumidifying zone 24 with the sealing strategy for separating the various gas routes.
- the ambient air passes under the web 21 through a channel 35 , formed on the one hand by the side wall 33 a of the eye 37 and on the other hand by the surface of the end plate 2 a of the adjacent fuel cell (or of the surface of a seal—not shown—between the fuel cells n and n+1 or 1 a and 1 b ).
- the channel 35 routes the air into the uptake channel 33 , through the opening 38 in the membrane 4 and via a her channel 39 via the side wall 33 b of the eye 37 into the outflow channel 29 .
- This arrangement enables the webs 20 , 21 to interact along their entire length (including the eye 37 ) with a sealing effect with the membrane 4 , i.e. this rests firmly on the webs 20 , 21 and thus the various gases are unproblematically separated and sealed off from one another.
- Barriers 40 separate the superposed uptake channels 33 of each fuel cell 1 a , 1 b and 1 c fluid-tight from one another, with the consequence that each fuel cell 1 a , 1 b , 1 e (or section A thereof) has its own humidity exchanger (section B) and the fluids from each fuel cell 1 a , 1 b and 1 c expelled on the cathode side remain unmixed.
- the route (shown by a broken line) from the channel 35 of one fuel cell to the channel 39 of the other fuel cell is blocked.
- the barriers 40 are of significance according to the invention if the fluid supply and discharge channels are connected so that fluid supply or discharge take place from one end of the stack 1 (cell 1 a here by way of example).
- the following pressure conditions then result in the stack 1 : as shown in the description of FIG. 2, the static pressure rises continuously in the fluid supply channel 10 a or 10 b from its entrance at cell 1 a and reaches its maximum at the last cell 1 c , with the consequence that the individual cells 1 a , 1 b , 1 c are supplied with different, ever higher pressures.
- each cell 1 a to 1 c now feeds the fluid discharge channel 10 a or 10 b , with the highest static pressure prevailing at the location of cell 1 c and the lowest at the location of cell 1 a.
- the pressure level in the fluid supply channel 10 a or 10 b is generally higher than in the fluid discharge channel 10 a or 10 b , but the pressures are comparatively low on the supply and discharge side in the case of the first cell in the stack 1 and comparatively high in the case of the last cell.
- the pressure differential is the same over the inlet of the inflow channel 28 and the outlet of the outflow channel 29 . The same applies for inlet and outlet of the anode area.
- the barriers 40 (FIG. 4) now help to prevent a pressure equalization across the channels 33 in the stack 1 .
- the conditions described above continue to apply.
- the figure shows a (schematic) routing of the fluid channels on the cathode side such that all channels are routed in the same fuel cell.
- the optimum routing of the channels 7 a and 7 b may entail the channels 33 , 35 and 39 being routed through adjacent fuel cells, which does not exceed the scope of the invention.
- Inventively significant is the humidity circuit on the cathode side and the fact that preferably with the help of the barriers 40 all cells in the stack 1 contain the same volume flow of fluid on the cathode side from the same collection channels 10 a and 10 b (the same applies for the fluids on the anode side).
- the exemplary embodiments represented in the figures show how fluid entering the cathode area can be humidified, in that the fluid exiting therefrom is dehumidified and this humidity is supplied to the incoming fluid. Analogously, humidity can also be removed from the fluid expelled from the anode area and added to the fluid entering therein.
- the layout of such a fuel cell is then analogous to that shown in the figures and can be executed by the person skilled in the art with the aid of the present description.
- fluid supplied both to the cathode area and the anode area with humidity originating from the respective fluid outflow (humidity from the anode area is routed back thereto, and humidity from the cathode area is routed back thereto).
- the present invention can by analogy also be applied to direct methanol fuel cells (DWF).
- DWF direct methanol fuel cells
- the drying-out of the membrane is not critical in such fuel cells, since methanol with water is used on the anode side, the ambient air used on the cathode side becomes charged with water recovered in accordance with the invention, so that a larger water loss can be avoided. Higher temperatures are permissible, resulting in increased operational output. Water is not supplied separately.
- the principle of the present invention can also be used to remove humidity from the outflowing fluid of the anode area or cathode area of a cell and to supply it to the inflowing fluid of the other in each case, i.e. the cathode area or anode area
- pure hydrogen can be recirculated in the anode area (the hydrogen leaving the anode area is returned to the supply line to the anode area, so that all of the hydrogen supplied to the cell participates in the chemical reaction), the hydrogen being dehumidified after leaving the anode area and the humidity gained being added to the fluid entering the cathode area. In this way humidity leaving the anode area enters the cathode area.
Abstract
So that the electrolyte membrane of a fuel cell in the inlet area of the fuels does not dry out, a humidity circuit is provided on the cathode side and/or anode side, by means of which e.g. a fluid entering the cell on the cathode side is first humidified, so that the membrane itself no longer discharges any humidity to the fluid, but can absorb it if required and thus does not dry out.
Description
- The present invention relates to a method and an apparatus for exchanging humidity between the fuels in a fuel cell. A fuel cell has a stack-like structure with an electrolyte arranged between end plates. Between the electrolyte and one end plate is an anode, and between the electrolyte and the other end plate is a cathode. Solid and liquid electrolytes are known; as the case may be, the electrolyte can be absorbed by a carrier structure or itself possesses the requisite solidity enabling it to be used in the cell. The operating temperatures also differ considerably and vary from ambient temperature to several hundred degrees C. and above.
- It is customary to combine individual fuel cells to form a fuel cell stack, in order to obtain the desired operating voltage by connecting a suitable number of individual cells in series.
- In one of the many known structural forms to which the invention can be applied, a polymer electrolyte membrane (PEM) is used in the fuel cell. In operation the fuel cell is then supplied on the anode side with e.g. hydrogen in gaseous form and on the cathode side with e.g. ambient air containing oxygen. The hydrogen and oxygen are used here by way of a non-limiting example.
- In the present case for the sake of simplicity all reaction partners which participate in the chemical reaction in a fuel cell are designated as fuels, as are their carrier fluids (e.g. ambient air as a carrier fluid for the reaction partner O2). The fuels are present in fluid form.
- In the presence of a catalytic converter, e.g. platinum, the hydrogen molecules split into protons and electrons, while on the cathode side oxygen molecules absorb electrons and are ionized into O2− ions. Since the membrane is designed as a proton conductor, the protons formed on the anode side diffuse through the membrane to the cathode; the electrons are supplied to the cathode via a separate electrical conductor, with an electrical load being inserted. The protons and oxygen ions react there to become water.
- The protons are transported in the membrane in the form of H3O+ ions; this is dependent upon the appropriate water content of the membrane. With a higher water content the ability of the membrane to conduct protons improves. The degree of operationally necessary humidity is therefore predetermined by the person skilled in the art, taking into account the parameters of the fuel cell and characteristics of the membrane.
- If the humidity is not substantially constant across the membrane, the fuel cell cannot be kept at an optimum operating point; areas of the membrane which are too dry reduce the production of current, since dryness makes it more difficult for protons to be transported through the membrane.
- In operation, the membrane continuously loses humidity, since as stated above, the protons are transported through the membrane via H3O+ ions. Furthermore, water is produced on the cathode side. In this way the air flow on the cathode side continuously becomes charged with humidity on its route across the membrane. In the area of the inlet, the air flow which is not as yet charged with humidity helps the membrane to dry out, while in the area of the outlet it tends to have excess humidity (condensation).
- As a result, the membrane is too dry on the inlet side, which as mentioned above is undesirable. If a fuel cell stack continues to be operated, the overly dry parts of the membrane of a fuel cell generate resistance via a corresponding production of heat, which, in turn, accelerates the drying out process. This leads to a significant reduction in cell output, overheating, and even destruction of the affected cell.
- Humidity refers not only to the presence of water. Just as the term “fluids” is used here to refer to all possible fuels, “humidity” refers to any substance which in the case of a given membrane (and given fuels) permits charges (such as protons in the case of PEM membranes) to be transported through the membrane.
- U.S. Pat. No. 4,973,530 discloses a method for regulating the humidity content in a fuel cell membrane by continuous addition of externally supplied water into the anode area and by continuous removal of humidity on the cathode side. For the addition of water a further membrane which is pervious to water is arranged next to the membrane of the fuel cell and the channel for the hydrogen is arranged in such an alternating pattern that it is routed back and forth in a zigzag fashion first via the membrane of the fuel cell, then via the water-pervious membrane, until both membranes are fully covered and the residual hydrogen can be expelled to the outside. A further, also water-pervious membrane is used to remove humidity from the cathode area with the same zigzag routing arrangement, in that a dry gas is routed over the further membrane, absorbs the humidity to be discharged, and expels it to the outside.
- It is further proposed to use hydrogen as a dry gas which is to be supplied to the anode area, with the advantage that the hydrogen then already contains a certain humidity before entering the area of the membrane of the fuel cell. To construct a stack of fuel cells it is proposed to create common supply and discharge channels routed through the stack for all anode-side and cathode-side areas, including the areas conveying water (for humidification) or a dry gas (for dehumidification), in that the same fluid-conveying lines are connected together through correspondingly cut holes in the membranes.
- It is now the object of the present invention to provide an improved fuel cell or a stack of fuel cells with controlled humidity management.
- The present invention relates to a system and method for humidity management in a fuel cell. The present invention is advantageous because humidity is removed from the fluid flow expelled from the cathode area and is added to the fluid flow which flows into the cathode area, a simple humidity circuit is produced which can be achieved without any greater construction effort and in particular does not require any further external gas or water circuits, as is the case in the above-cited prior art. Sufficient humidity needs only to be added to the fluid flowing into the cathode area as is necessary to keep the cathode-side inlet area of the electrolyte membrane above a critical humidity. Excess humidity can be expelled to the outside with the outflowing fluid. The same applies for the anode area. In the context of the invention both the cathode area and the anode area may be dehumidified.
- If a stack of fuel cells is formed from a plurality of fuel cells, it is customary to provide the individual fuel cells with common supply and discharge channels for the fuels, said channels running along or through the stack. Arrangements are preferred in which the supply and discharge channels terminate jointly at one end of the stack, the cathode-side connection of the respective fuel cell to the humidity exchanger associated therewith being kept separate from the same connections of adjacent fuel cells. Only the dehumidified fluid expelled from the humidity exchanger is fed back into the discharge channel common to all fuel cells.
- As a result, not only is the drop in pressure the same for each fuel cell in the fuel cell stack on the cathode side over the inlet in front of and the outlet after the humidity exchanger, but the volume flow or mass flow of fuels is also the same, so that the production of current is the same for each of the fuel cells in the stack. This is of great importance, since otherwise comparatively low current-producing fuel cells have to be powered by the rest of the stack, thereby reducing the efficiency of the stack.
- The novel features and method steps believed characteristic of the invention are set out in the claims below. The invention itself, however, as well as other features and advantages thereof, are best understood by reference to the detailed description, which follows, when read in conjunction with the accompanying drawing, wherein:
- FIG. 1 depicts a fuel cell stack according to the prior art, in schematic form,
- FIG. 2 depicts a cross-section through the stack in FIG. 1 in schematic form, with laterally routed fluid channels,
- FIG. 3 depicts a fuel cell according to the present invention, in schematic form, and
- FIG. 4 depicts a cross-section through a part of a fuel cell stack according to the present invention, in schematic form.
- FIG. 1 depicts schematically and by way of example a stack1 of fuel cells formed from two
PEM fuel cells 1 a and 1 b. The fuel cell stack 1 may comprise many fuel cells, with stacks having approximately 100 fuel cells being common. The present invention may also be applied to other than PEM fuel cells. Eachfuel cell 1 a, 1 b further comprisesend plates 2 a, 2 b, with the adjacent end plates of thecells 1 a, 1 b here being combined to form abipolar plate 3. Thefuel cells 1 a, 1 b of the stack 1 are constructed in the same way: between theend plates 2 a or 2 b and thebipolar plate 3 is apolymer electrolyte membrane 4 in each of thecells 1 a and 1 b. On opposite sides ofmembrane 4, i.e. on the side of theend plates 2 a or 2 b and on the side of thebipolar plate 3, ananode 5 or acathode 6 is arranged. Channels 7 a, 7 b are used to supply gaseous fuels, in this case on the anode side H2, or a fluid containing H2 (channels 7 a) and on the cathode side O2 or ambient air or another fluid containing O2 (channels 7 b). It is known in principle in the prior art for the channels 7 a and 7 b to be designed such that the transported fluids can be supplied as evenly as possible to the whole membrane surface. - For clarity purposes, the
collection channels 10 a and 10 b (running along thelateral surfaces channels 10 a) and discharging (channels 10 b) fluid in the stack 1 are depicted in FIG. 2. They run along the sides of the stack and are connected with each of the fuel cells of the stack 1 via the respective channels 7 a and 7 b of the fuel cells. Preferably thecollection channels 10 a and 10 b are open at one end, e.g. in the case of the first fuel cell of the stack 1, and connected to the fluid supply unit of the stack, while the other end (in the case of the last fuel cell) is blind, i.e. closed. An electrical load 8 is connected to ananode 5 or acathode 6 via a conductor 9. - FIG. 2 depicts in schematic form a cross-section through the fuel cell stack1 at the location of a
membrane 4. Themembrane 4 has amembrane body 13, via which protons are transported. Simultaneously, themembrane 4 has a sealing function at its edges: first of all theedge sections 14 seal off the gas supply channels and dischargechannels 10 a and 10 b which, as mentioned, run along the stack and feed the channels 7 a and 7 b (FIG. 1). Also shown is the channel 10 c for the supply of coolant and a channel 10 d for discharge of the coolant, said channels also formed byedge sections 14. Additionally, themembrane 4 has sealingedge sections 15 for the edges of the end orbipolar plates sections recesses 16 for tensile elements which hold the fuel cell stack 1 mechanically together. The layout shown in FIGS. 1 and 2 is known in principle to the person skilled in the art. - In operation, the pressure conditions described below prevail in the
channels 10 a and 10 b. Fluid supply (be it hydrogen or ambient air): at the inlet of therespective channel 10 a, 10 b high dynamic pressure, generated by the fluid pump 1 associated with the stack 1, and correspondingly low static pressure; further back in the channel the dynamic pressure falls and the static pressure increases, until at the end of the channel (at the last fuel cell in stack 1) the dynamic pressure is at its lowest and the static pressure at its highest. The individual cells in the stack are thus fed with different pressures. - The same conditions prevail in the case of fluid discharge: the individual cells feed the
respective discharge channel 10 a, 10 b along its length with the fluids to be discharged, so that toward the outlet of thechannel 10 a, 10 b the dynamic pressure increases and the static pressure decreases. - It is now advantageous to arrange the openings of the
channels 10 a and 10 b at the same end of the stack 1. This configuration is described further in conjunction with FIG. 4. - FIG. 3 shows in schematic form an “exploded view” of a
fuel cell 1 a or 1 b according to the present invention. - The cell comprises a section A in which the electrochemical reaction for current generation takes place, and of a section B which is designed as a humidity exchanger; sections A and B are separated from one another by the operationally interacting
webs anode area 22 and acathode area 23. Section B includes adehumidifying zone 24 and ahumidifying zone 25. Theareas zones membrane 4 which extends through thewhole cell 1 a, 1 b (see FIG. 1). The membrane may comprise a variety of materials. - The channels7 a, indicated by broken lines, run in the
anode area 22, and hydrogen flows through them in the direction of flow indicated by thearrows membrane 4 substantially evenly over the correspondingmembrane section 26. In thecathode area 23 the channels 7 b for even transport of oxygen or ambient air ran across the other side of themembrane section 26. - In the
humidifying zone 25 ambient air (or oxygen) enters section B of thecell 1 a, 1 b (arrow 30) via aninflow channel 28. The route of theinflow channel 28 is depicted in simple form so as not to overcomplicate the figure; however, the person skilled in the art will provide a route which is suitable for covering thewhole membrane section 27 evenly. - An
outflow channel 29 with an outlet at the location of thearrow 31 is shown in thedehumidifying zone 24, once again purely schematically with a simple route in order not to overcomplicate the figure. It is within the scope of the present invention that this and other discussed routes be of different configurations as may result from design choice and/or application requirements. - The humidity exchanger is thus situated in the
inflow channel 28 or the inflow line and in theoutflow channel 29 or the outflow line for the fluid supplied and discharged on the cathode side. - As mentioned, the sections A and B are separated from one another and sealed against fluid by the
webs membrane 4 also acting as part of the seal. Suitable sealing strategies are known to the person skilled in the art. Theinflow channel 28 and the channel 7 b of thecathode area 23 are connected via achannel section 32 passing under theweb 21. Thecathode area 23 and theoutflow channel 29 are connected via aninner uptake channel 33 formed by an opening oreye 37 of thewebs uptake channel 33 hasside walls membrane 4 has a corresponding opening for the unobstructed passage of the transported gas at the location of theuptake channel 33. - The
membrane 4 is, as a polymer electrolyte membrane, pervious to water. Accordingly, in section A H3O+ ions from theanode area 22 can reach the cathode area 23 (via membrane section 26) and in section B water from thedehumidifying zone 24 can reach the humidifying zone 25 (via membrane section 27). Naturally, instead of a single membrane different membranes may be used for section A and for section B respectively, and made of a different material if necessary. The person skilled in the art will select such an arrangement depending on the type of fuel used, the operating temperature and the type of humidifying medium. The use of different membranes lies within the scope of the present invention. - This arrangement allows freshly supplied ambient air from
inflow channel 28 to passmembrane section 27, pick up humidity, and then to pass under theweb 21 viachannel section 32 into channel 7 b, where it spreads along themembrane section 26 of thecathode area 23, and because of its increased humidity, prevents themembrane area 34, situated at the inlet of the channels 7 b, from drying out. As it continues on along themembrane section 26, the ambient air again picks up the humidity it loses in themembrane area 34, and then passes through theuptake channel 33 into thedehumidifying zone 24 of section B, where in theoutflow channel 29 it again loses a considerable part of its humidity, since this penetrates themembrane section 27 and is absorbed on the other side of themembrane 4 by the inflowing air. The required humidity is thus part of a simple circuit and need no longer be regularly supplied from the outside. - In the figure, the inflow and outflow of the fluid in the
inflow channel 28 andoutflow channel 29 have the same direction of flow, so that consequently the inflowing fluid is increasingly charged with humidity, and the fluid flowing in parallel loses humidity, until both (ideally) have the same humidity (namely half) compared to the original humidity differential. This “half” humidity value cannot be exceeded. - If still more humidity is to be taken up into the inflowing fluid, an inflowing and outflowing fluid can be routed in the reverse flow through section B, with the consequence that the inflowing fluid is exposed on its route to section A to ever higher humidity of the outflowing fluid, since the humidity of the latter is greatest immediately after leaving section A. Though the inflowing fluid picks up more and more humidity on its mute to section A, the humidity of the fluid flowing on the other side of the
membrane 4 also increases on this route, so that there is no limit on humidity to be transferred, as with parallel flow routing of the fluid. This arrangement is e.g. advantageous if sufficient surface area is available in the humidity exchanger. - FIG. 4 shows a partial cross-section along the line A*-A* of FIG. 3 through a fuel cell stack1 with three fuel cells n−1, n and n+1. The cells n and n+1 may correspond to the
cells 1 a and 1 b of FIG. 1. The ambient air route is shown out of thecathode area 23 into theoutflow channel 29 of thedehumidifying zone 24 with the sealing strategy for separating the various gas routes. - At the end of its route through the
cathode area 23, the ambient air passes under theweb 21 through achannel 35, formed on the one hand by theside wall 33 a of theeye 37 and on the other hand by the surface of the end plate 2 a of the adjacent fuel cell (or of the surface of a seal—not shown—between the fuel cells n and n+1 or 1 a and 1 b). Thechannel 35 routes the air into theuptake channel 33, through theopening 38 in themembrane 4 and via a herchannel 39 via theside wall 33 b of theeye 37 into theoutflow channel 29. - This arrangement enables the
webs membrane 4, i.e. this rests firmly on thewebs -
Barriers 40 separate thesuperposed uptake channels 33 of eachfuel cell 1 a, 1 b and 1 c fluid-tight from one another, with the consequence that eachfuel cell 1 a, 1 b, 1 e (or section A thereof) has its own humidity exchanger (section B) and the fluids from eachfuel cell 1 a, 1 b and 1 c expelled on the cathode side remain unmixed. The route (shown by a broken line) from thechannel 35 of one fuel cell to thechannel 39 of the other fuel cell is blocked. - The
barriers 40 are of significance according to the invention if the fluid supply and discharge channels are connected so that fluid supply or discharge take place from one end of the stack 1 (cell 1 a here by way of example). The following pressure conditions then result in the stack 1: as shown in the description of FIG. 2, the static pressure rises continuously in thefluid supply channel 10 a or 10 b from its entrance at cell 1 a and reaches its maximum at the last cell 1 c, with the consequence that theindividual cells 1 a, 1 b, 1 c are supplied with different, ever higher pressures. - At its outlet each cell1 a to 1 c now feeds the
fluid discharge channel 10 a or 10 b, with the highest static pressure prevailing at the location of cell 1 c and the lowest at the location of cell 1 a. - The following conditions occur in the stack during operation; the pressure level in the
fluid supply channel 10 a or 10 b is generally higher than in thefluid discharge channel 10 a or 10 b, but the pressures are comparatively low on the supply and discharge side in the case of the first cell in the stack 1 and comparatively high in the case of the last cell. For each cell the pressure differential is the same over the inlet of theinflow channel 28 and the outlet of theoutflow channel 29. The same applies for inlet and outlet of the anode area. - Thus the conditions are created whereby in each of the individual cells the same volume flow or mass flow of fuels essentially prevails as a result of the same pressure drop, and thus the intensity of the chemical reaction is the same, meaning that production of current is essentially the same in all cells.
- The barriers40 (FIG. 4) now help to prevent a pressure equalization across the
channels 33 in the stack 1. The conditions described above continue to apply. - If the
barriers 40 are removed, the pressure is equalized in thechannel 33 which is now continuous (but closed at its end), so that in section A of each cell at the inlet of the cathode area a different pressure, rising from the first to the last cell, prevails, but at the outlet of section A (in channel 33) a leveled-out pressure prevails. Un-equal pressure drop over section A for the different cells results in different volume flow or mass flow of fuel, causing the output of the individual cells to differ, which can be undesirable and harmful. - The figure shows a (schematic) routing of the fluid channels on the cathode side such that all channels are routed in the same fuel cell. However, the optimum routing of the channels7 a and 7 b may entail the
channels barriers 40 all cells in the stack 1 contain the same volume flow of fluid on the cathode side from thesame collection channels 10 a and 10 b (the same applies for the fluids on the anode side). - The exemplary embodiments represented in the figures show how fluid entering the cathode area can be humidified, in that the fluid exiting therefrom is dehumidified and this humidity is supplied to the incoming fluid. Analogously, humidity can also be removed from the fluid expelled from the anode area and added to the fluid entering therein. The layout of such a fuel cell is then analogous to that shown in the figures and can be executed by the person skilled in the art with the aid of the present description. Naturally it is also possible to charge fluid supplied both to the cathode area and the anode area with humidity originating from the respective fluid outflow (humidity from the anode area is routed back thereto, and humidity from the cathode area is routed back thereto).
- The present invention can by analogy also be applied to direct methanol fuel cells (DWF). Although the drying-out of the membrane is not critical in such fuel cells, since methanol with water is used on the anode side, the ambient air used on the cathode side becomes charged with water recovered in accordance with the invention, so that a larger water loss can be avoided. Higher temperatures are permissible, resulting in increased operational output. Water is not supplied separately.
- The principle of the present invention can also be used to remove humidity from the outflowing fluid of the anode area or cathode area of a cell and to supply it to the inflowing fluid of the other in each case, i.e. the cathode area or anode area For example, pure hydrogen can be recirculated in the anode area (the hydrogen leaving the anode area is returned to the supply line to the anode area, so that all of the hydrogen supplied to the cell participates in the chemical reaction), the hydrogen being dehumidified after leaving the anode area and the humidity gained being added to the fluid entering the cathode area. In this way humidity leaving the anode area enters the cathode area.
- The invention being thus described, it will be obvious that the same may be varied in many ways. The variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
Claims (23)
1. A method of providing humidity to an electrolyte membrane of a fuel cell, said membrane running between a cell anode area and a cell cathode area, comprising the step of exchanging humidity between fluid flowing from one of said anode and cathode areas to fluid flowing into said one of said anode and cathode areas.
2. The method according to claim 1 , wherein said step of exchanging her comprises the steps of routing said fluid flowing from said one of said anode and cathode areas along an opposite side of a membrane to said fluid flowing into said one of said anode and cathode areas, said membrane being pervious to said humidity, such that said exchanged fluid passes through said membrane, and
further comprising the step of discharging said fluid flowing from one of said anode and cathode areas after said step of exchanging.
3. The method according to claim 2 , wherein said fluid flowing from one of said anode and cathode areas and said fluid flowing into said one of said anode and cathode areas comprise one of a same, opposite, and cross-current-routed direction of flow.
4. The method according to claim 1 , wherein said fuel cell comprises a plurality of fuel cells each comprising separate channels for accommodating flowing fluid, said plurality of fuel cells combine to form a fuel stack, and each of said plurality of fuel cells comprise a dehumidification unit.
5. The method according to claim 4 , wherein a separate membrane section pervious to humidity is assigned to each cathode area of each of said plurality of fuel cells.
6. The method according to claim 2 , wherein said fuel cell comprises a plurality of fuel cells each comprising separate channels for accommodating flowing fluid, said plurality of fuel cells combine to form a fuel stack, and each of said plurality of fuel cells comprise a dehumidification unit.
7. The method according to claim 6 , wherein a separate membrane section pervious to humidity is assigned to each cathode area of each of said plurality of fuel cells.
8. The method according to claim 3 , wherein said fuel cell comprises a plurality of fuel cells each comprising separate channels for accommodating flowing fluid, said plurality of fuel cells combine to form a fuel stack, and each of said plurality of fuel cells comprise a dehumidification unit.
9. The method according to claim 8 , wherein a separate membrane section pervious to humidity is assigned to each cathode area of each of said plurality of fuel cells.
10. A fuel cell, comprising:
a cathode area,
an anode area,
an electrolyte membrane;
an inflow line for accommodating fluid to one of said cathode area and anode area,
an outflow line for accommodating fluid from said one of said cathode area and anode area, and
a humidity exchanger functionally associated with one of said cathode area and anode area and positioned along one of said inflow line and out flow line, said exchanger providing humidification of fluid supplied to said one of said cathode area and anode area.
11. The fuel cell according to claim 10 , wherein said humidity exchanger comprises a humidifying and dehumidifying zone separated by a humidity pervious membrane, and wherein said inflow line is positioned in said humidifying zone and the outflow line is positioned in said dehumidifying zone.
12. The fuel cell according to claim 11 , further comprising an electrolyte membrane, and said electrolyte membrane and said humidity pervious membranes comprise substantially similar materials.
13. The fuel cell according to claim 12 , wherein said electrolyte membrane and said humidity pervious membrane combine to form different portions of a single membrane.
14. The fuel cell according to claim 10 , further comprising a plurality of fuel cells combined to form a stack, wherein each of said plurality of fuel cells has a separate humidity exchanger connected to said cathode area of each of said plurality of fuel cells.
15. The fuel cell according to claim 14 , wherein at least sections of one of said inflow and outflow lines of each of said plurality of fuel cells run through an adjacent one of said plurality of fuel cells.
16. The fuel cell according to claim 10 , further comprising a plurality of fuel cells combined to form a stack, wherein each of said plurality of fuel cells has a separate humidity exchanger connected exclusively to a cathode area of each of said plurality of fuel cells.
17. The fuel cell according to claim 16 , wherein at least sections of one of said inflow and outflow lines of each of said plurality of fuel cells run through an adjacent one of said plurality of fuel cells.
18. The fuel cell according to claim 11 , further comprising a plurality of fuel cells combined to form a stack, wherein each of said plurality of fuel cells has a separate humidity exchanger connected exclusively to a cathode area of each of said plurality of fuel cells.
19. The fuel cell according to claim 18 , wherein at least sections of one of said inflow and outflow lines of each of said plurality of fuel cells run through an adjacent one of said plurality of fuel cells.
20. The fuel cell according to claim 12 , further comprising a plurality of fuel cells combined to form a stack, wherein each of said plurality of fuel cells has a separate humidity exchanger connected exclusively to a cathode area of each of said plurality of fuel cells.
21. The fuel cell according to claim 20 , wherein at least sections of one of said inflow and outflow lines of each of said plurality of fuel cells run through an adjacent one of said plurality of fuel cells.
22. The fuel cell according to claim 13 , further comprising a plurality of fuel cells combined to form a stack, wherein each of said plurality of fuel cells has a separate humidity exchanger connected exclusively to a cathode area of each of said plurality of fuel cells.
23. The fuel cell according to claim 22 , wherein at least sections of one of said inflow and outflow lines of each of said plurality of fuel cells run through an adjacent one of said plurality of fuel cells.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/608,088 US20040265653A1 (en) | 2003-06-30 | 2003-06-30 | Method and apparatus for humidification of the membrane of a fuel cell |
PCT/EP2004/006206 WO2005004265A1 (en) | 2003-06-30 | 2004-06-09 | Method and apparatus for internal humidification of the membrane of a fuel cell |
EP04736397.3A EP1642352B1 (en) | 2003-06-30 | 2004-06-09 | Method and apparatus for internal humidification of the membrane of a fuel cell |
US11/903,171 US7645530B2 (en) | 2003-06-30 | 2007-09-20 | Method and apparatus for humidification of the membrane of a fuel cell |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/608,088 US20040265653A1 (en) | 2003-06-30 | 2003-06-30 | Method and apparatus for humidification of the membrane of a fuel cell |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US11/903,171 Continuation US7645530B2 (en) | 2003-06-30 | 2007-09-20 | Method and apparatus for humidification of the membrane of a fuel cell |
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US20040265653A1 true US20040265653A1 (en) | 2004-12-30 |
Family
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Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
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US10/608,088 Abandoned US20040265653A1 (en) | 2003-06-30 | 2003-06-30 | Method and apparatus for humidification of the membrane of a fuel cell |
US11/903,171 Expired - Fee Related US7645530B2 (en) | 2003-06-30 | 2007-09-20 | Method and apparatus for humidification of the membrane of a fuel cell |
Family Applications After (1)
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US11/903,171 Expired - Fee Related US7645530B2 (en) | 2003-06-30 | 2007-09-20 | Method and apparatus for humidification of the membrane of a fuel cell |
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US (2) | US20040265653A1 (en) |
EP (1) | EP1642352B1 (en) |
WO (1) | WO2005004265A1 (en) |
Cited By (10)
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EP2059967A1 (en) * | 2006-08-16 | 2009-05-20 | Hytheon Inc. | Optimizing performance of end cells in a fuel cell stack |
US20100304233A1 (en) * | 2009-05-28 | 2010-12-02 | Delphi Technologies, Inc. | Fuel cell assembly |
US11754225B2 (en) | 2021-03-16 | 2023-09-12 | Marathon Petroleum Company Lp | Systems and methods for transporting fuel and carbon dioxide in a dual fluid vessel |
US11752472B2 (en) | 2019-12-30 | 2023-09-12 | Marathon Petroleum Company Lp | Methods and systems for spillback control of in-line mixing of hydrocarbon liquids |
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US20100304258A1 (en) * | 2009-05-26 | 2010-12-02 | Chan Alistair K | System and method of altering temperature of an electrical energy storage device or an electrochemical energy generation device using high thermal conductivity materials |
US8101293B2 (en) * | 2009-05-26 | 2012-01-24 | The Invention Science Fund I, Llc | System for altering temperature of an electrical energy storage device or an electrochemical energy generation device using high thermal conductivity materials based on states of the device |
US9065159B2 (en) | 2009-05-26 | 2015-06-23 | The Invention Science Fund I, Llc | System and method of altering temperature of an electrical energy storage device or an electrochemical energy generation device using microchannels |
US20100304259A1 (en) * | 2009-05-26 | 2010-12-02 | Searete Llc. A Limited Liability Corporation Of The State Of Delaware | Method of operating an electrical energy storage device or an electrochemical energy generation device using high thermal conductivity materials during charge and discharge |
US8802266B2 (en) * | 2009-05-26 | 2014-08-12 | The Invention Science Fund I, Llc | System for operating an electrical energy storage device or an electrochemical energy generation device using microchannels based on mobile device states and vehicle states |
US8715875B2 (en) * | 2009-05-26 | 2014-05-06 | The Invention Science Fund I, Llc | System and method of operating an electrical energy storage device or an electrochemical energy generation device using thermal conductivity materials based on mobile device states and vehicle states |
DE102012218303A1 (en) * | 2011-10-08 | 2013-04-11 | Volkswagen Ag | Method for producing humidifier for humidification of process gases for fuel cell, involves stacking generated strips on humidifier stack which is laminated with water-permeable membrane |
US10673082B2 (en) | 2015-12-09 | 2020-06-02 | Parker-Hannifin Corporation | System and method for fuel cell cathode gas humidification |
CN113611890B (en) * | 2018-11-16 | 2023-02-21 | 上海恒劲动力科技有限公司 | Streamline-shaped flow dividing structure and method of flow guide channel |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4973530A (en) * | 1989-12-21 | 1990-11-27 | The United States Of America As Represented By The United States Department Of Energy | Fuel cell water transport |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6416895B1 (en) * | 2000-03-09 | 2002-07-09 | Ballard Power Systems Inc. | Solid polymer fuel cell system and method for humidifying and adjusting the temperature of a reactant stream |
DE19921007C1 (en) * | 1999-05-06 | 2000-11-16 | Dornier Gmbh | PEM fuel cell with membrane electrode assembly has gas channels integrated in bipolar plates cladded with fluid transporting layer for damping membranes via condensed water |
JP2000323159A (en) * | 1999-05-11 | 2000-11-24 | Fuji Electric Co Ltd | Solid polymer type fuel cell |
-
2003
- 2003-06-30 US US10/608,088 patent/US20040265653A1/en not_active Abandoned
-
2004
- 2004-06-09 EP EP04736397.3A patent/EP1642352B1/en active Active
- 2004-06-09 WO PCT/EP2004/006206 patent/WO2005004265A1/en active Application Filing
-
2007
- 2007-09-20 US US11/903,171 patent/US7645530B2/en not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4973530A (en) * | 1989-12-21 | 1990-11-27 | The United States Of America As Represented By The United States Department Of Energy | Fuel cell water transport |
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EP2059967A1 (en) * | 2006-08-16 | 2009-05-20 | Hytheon Inc. | Optimizing performance of end cells in a fuel cell stack |
EP2059967A4 (en) * | 2006-08-16 | 2012-02-29 | Hyteon Inc | Optimizing performance of end cells in a fuel cell stack |
US20100304233A1 (en) * | 2009-05-28 | 2010-12-02 | Delphi Technologies, Inc. | Fuel cell assembly |
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US11774990B2 (en) | 2019-12-30 | 2023-10-03 | Marathon Petroleum Company Lp | Methods and systems for inline mixing of hydrocarbon liquids based on density or gravity |
US11794153B2 (en) | 2019-12-30 | 2023-10-24 | Marathon Petroleum Company Lp | Methods and systems for in-line mixing of hydrocarbon liquids |
US11754225B2 (en) | 2021-03-16 | 2023-09-12 | Marathon Petroleum Company Lp | Systems and methods for transporting fuel and carbon dioxide in a dual fluid vessel |
US11774042B2 (en) | 2021-03-16 | 2023-10-03 | Marathon Petroleum Company Lp | Systems and methods for transporting fuel and carbon dioxide in a dual fluid vessel |
US11815227B2 (en) | 2021-03-16 | 2023-11-14 | Marathon Petroleum Company Lp | Scalable greenhouse gas capture systems and methods |
US11807945B2 (en) | 2021-08-26 | 2023-11-07 | Marathon Petroleum Company Lp | Assemblies and methods for monitoring cathodic protection of structures |
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US11965317B2 (en) | 2023-08-28 | 2024-04-23 | Marathon Petroleum Company Lp | Systems, methods, and controllers to enhance heavy equipment warning |
Also Published As
Publication number | Publication date |
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US7645530B2 (en) | 2010-01-12 |
US20080182140A1 (en) | 2008-07-31 |
WO2005004265A1 (en) | 2005-01-13 |
EP1642352B1 (en) | 2013-11-13 |
EP1642352A1 (en) | 2006-04-05 |
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