WO2006079800A1 - Fuel cell cathodes - Google Patents
Fuel cell cathodes Download PDFInfo
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- WO2006079800A1 WO2006079800A1 PCT/GB2006/000246 GB2006000246W WO2006079800A1 WO 2006079800 A1 WO2006079800 A1 WO 2006079800A1 GB 2006000246 W GB2006000246 W GB 2006000246W WO 2006079800 A1 WO2006079800 A1 WO 2006079800A1
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- Prior art keywords
- layer
- cathode
- fuel cell
- lscf
- fired
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- 239000000446 fuel Substances 0.000 title claims abstract description 36
- 238000000034 method Methods 0.000 claims abstract description 50
- 238000010304 firing Methods 0.000 claims description 18
- 239000012298 atmosphere Substances 0.000 claims description 15
- 238000009694 cold isostatic pressing Methods 0.000 claims description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 6
- 238000000462 isostatic pressing Methods 0.000 claims description 6
- 238000007650 screen-printing Methods 0.000 claims description 6
- 239000002131 composite material Substances 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 238000009718 spray deposition Methods 0.000 claims description 3
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 2
- 210000004027 cell Anatomy 0.000 description 33
- 239000003792 electrolyte Substances 0.000 description 20
- 238000012545 processing Methods 0.000 description 14
- 230000008569 process Effects 0.000 description 13
- FFBHFFJDDLITSX-UHFFFAOYSA-N benzyl N-[2-hydroxy-4-(3-oxomorpholin-4-yl)phenyl]carbamate Chemical compound OC1=C(NC(=O)OCC2=CC=CC=C2)C=CC(=C1)N1CCOCC1=O FFBHFFJDDLITSX-UHFFFAOYSA-N 0.000 description 10
- 238000007254 oxidation reaction Methods 0.000 description 8
- 239000000758 substrate Substances 0.000 description 8
- 238000005259 measurement Methods 0.000 description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical group [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000006722 reduction reaction Methods 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- 239000000919 ceramic Substances 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 238000005245 sintering Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 239000011195 cermet Substances 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000001627 detrimental effect Effects 0.000 description 2
- 239000003085 diluting agent Substances 0.000 description 2
- 238000007732 electrostatic spray assisted vapour deposition Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 238000010345 tape casting Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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- 210000003850 cellular structure Anatomy 0.000 description 1
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- 238000001652 electrophoretic deposition Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229910021526 gadolinium-doped ceria Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910000473 manganese(VI) oxide Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
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- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000010606 normalization Methods 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
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- 239000010409 thin film Substances 0.000 description 1
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8605—Porous electrodes
- H01M4/8621—Porous electrodes containing only metallic or ceramic material, e.g. made by sintering or sputtering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/8647—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites
- H01M4/8657—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites layered
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/88—Processes of manufacture
- H01M4/8878—Treatment steps after deposition of the catalytic active composition or after shaping of the electrode being free-standing body
- H01M4/8882—Heat treatment, e.g. drying, baking
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/88—Processes of manufacture
- H01M4/8878—Treatment steps after deposition of the catalytic active composition or after shaping of the electrode being free-standing body
- H01M4/8896—Pressing, rolling, calendering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/9016—Oxides, hydroxides or oxygenated metallic salts
- H01M4/9025—Oxides specially used in fuel cell operating at high temperature, e.g. SOFC
- H01M4/9033—Complex oxides, optionally doped, of the type M1MeO3, M1 being an alkaline earth metal or a rare earth, Me being a metal, e.g. perovskites
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/023—Porous and characterised by the material
- H01M8/0236—Glass; Ceramics; Cermets
-
- 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
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M8/124—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte
- H01M8/1246—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides
- H01M8/126—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides the electrolyte containing cerium oxide
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/027—Negative electrodes
-
- 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
- Y02E60/10—Energy storage using batteries
-
- 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 present invention relates to a method of producing fuel cell cathodes and to fuel cell cathodes.
- Solid oxide fuel cell cathodes based on LSCF are common in the field. This material exhibits the necessary mixed electronic and ionic conductivity and chemical stability for functioning as an SOFC cathode at typical operating temperatures.
- LSCF based cathode systems in general involves the fabrication of a single green ceramic layer by an established ceramic processing route. Such routes include tape casting, screen-printing, doctor blading and electrophoretic deposition.
- the green processed layer is subsequently sintered in air at a temperature in the range 900-1000 0 C in order to retain a high porosity.
- LSCF cathodes in reducing (low oxygen partial pressure) atmospheres cannot be satisfactorily executed because extensive aggressive reduction of the LSCF by hydrogen is suspected to induce a partial phase change in the cathode. This breakdown from a single phase is detrimental to both cathode function and structure and is generally deemed unacceptable for subsequent cathode and fuel cell performance.
- the electrolyte is fired in air at 1400° C or above and if the anode is nickel-based (generally a Ni/YSZ cermet), the anode is left in its fully oxidised state throughout the entirety of cell fabrication, and the nickel oxide is not reduced down to metallic nickel until the first operating cycle of the cell.
- Cells of this type are typically operated in the 700-900 0 C temperature range.
- the present invention aims to overcome the prior art disadvantages and to provide an improved cathode fabrication route and cathodes fabricated by same.
- a method of producing a fuel cell cathode comprising the steps of: (i) providing a primary layer comprising LSCF;
- the primary layer is provided on an electrolyte, more preferably a dense electrolyte, more preferably as dense CGO electrolyte.
- the primary layer on the electrolyte is provided on an anode, more preferably a porous anode, more preferably still a Ni-CGO porous anode.
- the anode is preferably provided on a substrate, more preferably a porous substrate, more preferably still a porous ferritic stainless steel substrate.
- the perovskite-based electrode comprises LSCF.
- the primary layer and the current collecting layer can both comprise LSCF.
- primary layers are those comprising an LSCF/CGO composite.
- the primary layer has a thickness of about 0.5-20 ⁇ m, more particularly about 1-10 ⁇ m, more particularly about 1.5-5 ⁇ m.
- the isostatic pressing is cold isostatic pressing.
- the isostatic pressing is performed at a pressure of about 10- 300 MPa, more particularly about 20-100 MPa, more particularly about 30-70 MPa.
- the current collecting layer has a thickness of about 5-100 ⁇ m, more particularly about 10-70 ⁇ m, more particularly about 30-50 ⁇ m.
- the step of firing the bi-layer cathode is performed at a temperature of about 700-900 0 C, more particularly at about 800-900 0 C.
- the bi-layer cathode is fired in the p ⁇ 2 range of about 10 '10 - 10 "
- the bi-layer cathode is fired under a dilute, buffered H 2 /H 2 O atmosphere.
- bi-layer cathode is re-oxidised after being fired in said reducing atmosphere, particularly at a temperature of about 700 0 C.
- An example of a way in which the methods of the present invention can be used to make the fuel cell cathodes includes the following "Process 1 " in which the following steps are performed: (i) An LSCF/CGO composite 'active' layer (i.e. primary layer) is laid down by e.g. spray deposition or screen-printing;
- Cold isostatic pressing of the 'active' (i.e. primary) layer is then performed.
- 'active' (i.e. primary) layer is then performed.
- CIP Cold Isostatic Pressing
- the results achieved are a notable improvement over the prior art.
- a factor contributing to the lower temperature performance enhancement lies in the reduction of the cathode 'active' layer during cathode firing.
- the reaction produces a highly porous microstructure with porosity believed to be on the nano-scale.
- This microstructure possesses a vastly increased active surface area close to the electrolyte surface, and this increased specific surface area manifests itself as greatly reduced area specific resistance (ASR).
- ASR area specific resistance
- the bi-layer cathode is fired under a dilute air Argon or air Nitrogen atmosphere.
- the bi-layer cathode can be fired in the p ⁇ 2 range of about 10 "1 - ICT 10 , for example in the p ⁇ 2 range of about lO ⁇ -lO "5 .
- An example of a way in which the methods of the present invention can be used to make the fuel cell cathodes includes the following "Process 2" in which the following steps are performed: (i) As per Process 1 ; (ii) As per Process 1; (iii) As per Process 1;
- the green bi-layer cathode is fired under a dilute air in diluent gas (such a diluent gas being Argon or Nitrogen) environment in the p ⁇ 2 range lO ⁇ -lO "10 .
- diluent gas such as Argon or Nitrogen
- step (iv) of Process 1 The additional advantage of this processing step as compared to step (iv) of Process 1 is that is occurs in a more oxidising environment, resulting in a greater number of ion vacancies in the cathode lattice, greater cathode conductivity, lower ASR and thus greater cell operating performance. In addition, it removes the need for a re-oxidation step (as in Process 1 step (v)), as this can occur when the fuel cell is first used without any degrading or structural risks associated with re-oxidation from a more reduced state.
- the method of the present invention produces a functional, bi-layer cathode possessing a unique and beneficial structure having a microporous structure in the current collector and active (i.e. primary) layers capable of performing well in the 500-600 0 C operating temperature range.
- Cathodes processed by this route exhibited exceptional performance as shown in Figure 2, and when used with the metal supported IT-SOFC fuel cell of GB 2368450 they maintained their integrity throughout processing and subsequent fuel cell operation.
- a bi-layer fuel cell cathode comprising first and second layers, said first layer comprising LSCF, said second layer comprising a perovskite-based electrode, one of said first and second layers being isostatically pressed.
- bi-layer fuel cell cathodes have a novel microstructure, an example of which is shown in Figure 1 and which, as detailed above, enables previously unreported and unexpectedly high performance in the 500-600 °C temperature range.
- the bi-layer fuel cell cathode can be made according to the method of the present invention. Also provided according to the present invention is a fuel cell incorporating a cathode according to the present invention.
- Figure 1 shows a cross-sectional scanning electron microscope (SEM) image of a substrate-supported fuel cell comprising a bi-layer cathode structure, a dense electrolyte, a porous anode structure and a metal substrate.
- the top layer of the bi-layer cathode structure is the current collector, and the layer underneath is the primary layer;
- Figure 2 shows (bottom) a Cole-Cole plot of a conventional air fired LSCF cathode measured at 600° C, showing a relatively high ASR; and (top) Cole-Cole plots of two LSCF cathodes made according to the present invention - one (dashed line) fired in p ⁇ 2 of 10 "17 and one (solid line) fired in p ⁇ 2 of 10 '3 , both measured at 600° C, showing significantly lower ASR values.
- X-axes show Z' (ohm).
- Y-axes show Z" (ohm); and
- Figure 3 shows the differing power densities obtained using a fuel cell of
- GB 2368450 made with an LSCF cathode sintered at a ⁇ 2 of 10 " 17 atm as per Process A (below) and for a LSCF cathode sintered at a p ⁇ 2 of 10 "3 atm as per Process B (below). Data was obtained at 600 0 C in wet 97% H 2 and flowing air.
- X-axis shows current density (A cm ' );
- Y-axes show (left, for curves originating at
- a symmetrical LSCF electrode half-cell on a CGO support was prepared by Process 1 and another by Process 2 (above).
- an active LSCF layer of 5 ⁇ m was screen-printed on a CGO electrolyte, and cold isostatic pressing to 50MPa performed.
- a 35 ⁇ m current collector layer of LSCF was screen-printed on to define a bi-layer cathode, and the cathode assembly was fired in a H 2 O/H 2 reducing atmosphere of 10 "17 at 900° C for 1 hour.
- the cathode was subsequently heated in air at 700° C for 30 minutes prior to being used and measurement taking place.
- Process B the following process (Process B) was performed.
- an active LSCF layer of 5 ⁇ m was screen-printed on a CGO electrolyte, and cold isostatic pressing to 50MPa performed.
- a 35 ⁇ m current collector layer of LSCF was then screen-printed on to define a bi-layer cathode, and the cathode assembly was fired in Ar/air reducing atmosphere of 10 "3 at 900° C for 1 hour. No subsequent cathode conditioning in air was required.
- results show ASR values of over 3 ⁇ /cm 2 for the air fired cathode, less than 0.5 ⁇ /cm 2 for the higher reducing firing and less than 0.15 ⁇ /cm 2 for the slightly reducing atmosphere, thus showing the advantages of being able to fire LSCF cathodes in a partially reducing atmosphere.
- Figure 3 shows the results, with a maximum power density of 0.465 W/cm 2 from the second cathode process compared to 0.32 W/cm 2 from the first cathode process.
- the structure of the cathodes obtained using Process A is shown in Figure 1. From top to bottom, the first (black) layer is air; the second layer is current collector; the third layer is the active (i.e. primary) layer; the second and third layers together define the bi- layer cathode; the fourth layer is the dense CGO electrolyte; the fifth layer is the Ni- CGO anode; and the sixth (bottom) layer is the ferritic stainless steel substrate.
Abstract
The present invention relates to a method of producing a fuel cell cathode, fuel cell cathodes, and fuel cells comprising same.
Description
FUEL CELL CATHODES
The present invention relates to a method of producing fuel cell cathodes and to fuel cell cathodes.
Solid oxide fuel cell cathodes based on LSCF (an example of which is Lao.6Sro.4Co0.2Feo.803) are common in the field. This material exhibits the necessary mixed electronic and ionic conductivity and chemical stability for functioning as an SOFC cathode at typical operating temperatures.
Conventional processing of LSCF based cathode systems in general involves the fabrication of a single green ceramic layer by an established ceramic processing route. Such routes include tape casting, screen-printing, doctor blading and electrophoretic deposition. The green processed layer is subsequently sintered in air at a temperature in the range 900-1000 0C in order to retain a high porosity.
Examples of these prior-art processes for preparing LSCF cathodes include screen printing and firing in air at 950 0C for 2 hours (S.P. Jiang, A comparison of O2 reduction reactions on porous (La5Sr)MnO3 and (La5Sr)(Co5Fe)O3 electrodes - Solid State Ionics
146 (2002) 1-22), LSCF sol screen printing and heating in air at 900 0C for 4 hours (J.
Liu, A. Co5 S. Paulson, V. Birss, Oxygen reduction at sol-gel derived
Lao.8Sro.2Cθo.8Fe0.203 cathodes - Solid State Ionics, available online 03 Jan 2006), wet dropping LSCF sol-precursor as the working electrode and heating in air at 900 0C for 4 hours (Liu et al. 2006, supra) , spin casting LSCF slurry and sintering in air at temperature ranges from 900 - 1250 0C for 0.2 - 4 hours (E. Murray, M. Sever, S.
Barnett, Electrochemical performance of (La,Sr)(Co,Fe)θ3-(Ce,Gd)O3 composite cathodes - Solid State Ionics 148 (2002) 27-34), and electrostatic spray assisted vapour deposition (ESAVD) technique for thin film LSCF heating at 300 - 400 0C followed by brushing on LSCF tape cast slurry and drying in air at 1000 0C for 12 minutes ( J-M
Bae, B. Steele, Properties of LaC6SrC4COc2FeC8O3-S (LSCF) double layer cathodes on
gadolinium-doped cerium oxide (CGO) electrolytes - Solid State Ionics 106 (1998) 247- 253).
Notably, conventional LSCF cathode processing requires that the sintering step is carried out in air. Conventional wisdom to date supports the view that the firing of
LSCF cathodes in reducing (low oxygen partial pressure) atmospheres cannot be satisfactorily executed because extensive aggressive reduction of the LSCF by hydrogen is suspected to induce a partial phase change in the cathode. This breakdown from a single phase is detrimental to both cathode function and structure and is generally deemed unacceptable for subsequent cathode and fuel cell performance.
In summary, conventional LSCF processing involves the firing of a green LSCF layer in air between 900 °C and 1000 °C. For the majority of current SOFC designs this processing route does not present any serious problems. For these all-ceramic (anode or electrolyte supported) fuel cell systems, which possess YSZ electrolytes, neither the cathode sintering atmosphere nor the cathode sintering temperature are detrimental to cell integrity. For all such systems, the electrolyte is fired in air at 1400° C or above and if the anode is nickel-based (generally a Ni/YSZ cermet), the anode is left in its fully oxidised state throughout the entirety of cell fabrication, and the nickel oxide is not reduced down to metallic nickel until the first operating cycle of the cell. Cells of this type are typically operated in the 700-900 0C temperature range.
For a metal supported SOFC that operates below 700° C (as described in e.g. GB 2368450), which possesses a Ni/CGO cermet anode in the reduced state and a CGO electrolyte fired in the region of 1000 °C, conventional cathode firing under air poses a threat to the maintenance of cell integrity during cell processing. The principal source of potential problems is anode re-oxidation and the associated volume changes during cathode firing in air, which can result in catastrophic electrolyte failure due to cracking and/or delaminating and/or rupture. Secondary to this problem, because of the supporting steel substrate, issues concerning extensive steel oxidation and volatile steel species migration also arise when processing at high temperatures (such as processing temperatures above 1000 0C). In addition to the stated problems with maintaining cell integrity during cathode firing, a further consideration exists. Due to the significant
electronic conductivity of CGO at temperatures above 650 0C the cell design as described in GB 2368450 requires a cathode to function acceptably in the lower temperature range of 500-600 °C.
Whilst these problems do not prevent the operation of the fuel cells, it is desirable to improve and simplify component manufacture and to improve fuel cell performance.
The present invention aims to overcome the prior art disadvantages and to provide an improved cathode fabrication route and cathodes fabricated by same.
According to a first aspect of the present invention there is provided a method of producing a fuel cell cathode, the method comprising the steps of: (i) providing a primary layer comprising LSCF;
(ii) isostatically pressing said primary layer in the pressure range 10-300 MPa;
(iii) providing on said primary layer a current collecting layer comprising a perovskite-based electrode, to define a bi-layer cathode; and (iv) firing said bi-layer cathode in a reducing atmosphere.
Preferably, the primary layer is provided on an electrolyte, more preferably a dense electrolyte, more preferably as dense CGO electrolyte.
Preferably, the primary layer on the electrolyte is provided on an anode, more preferably a porous anode, more preferably still a Ni-CGO porous anode.
The anode is preferably provided on a substrate, more preferably a porous substrate, more preferably still a porous ferritic stainless steel substrate.
In certain embodiments, the perovskite-based electrode comprises LSCF. Thus, the primary layer and the current collecting layer can both comprise LSCF.
Particular examples of primary layers are those comprising an LSCF/CGO composite.
In certain embodiments, the primary layer has a thickness of about 0.5-20 μm, more particularly about 1-10 μm, more particularly about 1.5-5 μm.
In certain embodiments, the isostatic pressing is cold isostatic pressing.
In various embodiments, the isostatic pressing is performed at a pressure of about 10- 300 MPa, more particularly about 20-100 MPa, more particularly about 30-70 MPa.
In various embodiments, the current collecting layer has a thickness of about 5-100 μm, more particularly about 10-70 μm, more particularly about 30-50 μm.
hi certain embodiments, the step of firing the bi-layer cathode is performed at a temperature of about 700-900 0C, more particularly at about 800-900 0C.
hi certain embodiments, the bi-layer cathode is fired in the pθ2 range of about 10'10 - 10"
20
hi certain embodiments, the bi-layer cathode is fired under a dilute, buffered H2/H2O atmosphere.
hi certain embodiments, bi-layer cathode is re-oxidised after being fired in said reducing atmosphere, particularly at a temperature of about 700 0C.
An example of a way in which the methods of the present invention can be used to make the fuel cell cathodes includes the following "Process 1 " in which the following steps are performed: (i) An LSCF/CGO composite 'active' layer (i.e. primary layer) is laid down by e.g. spray deposition or screen-printing;
(ii) Cold isostatic pressing of the 'active' (i.e. primary) layer is then performed. In the field of SOFC processing, to isostatically press an electrode when considering microstructure is counter-intuitive. A general theme running through electrode processing is a desire to create and preserve porosity due to mass
transport and gas access considerations. Cold Isostatic Pressing (CIP) is a technique normally associated with the removal of porosity to create a denser product. In this case, CIP is employed in order to improve the contact between electrolyte and cathode to enable a firing temperature below typical LSCF cathode firing temperatures. Results revealed that the improvement in performance gained by pressing, and hence improved cathode- electrode contact, significantly outweighed any degradation due to loss of cathode porosity; (iii) An LSCF current collecting layer is applied by e.g. spray deposition or screen printing, creating a green bi-layer cathode; (iv) The green bi-layer cathode is fired under a dilute, buffered H2OZH2 atmosphere in the pθ2 range 10"10-10"20. As discussed above, for LSCF based cathode systems, conventional wisdom is of the view that low pθ2 firing is not possible due to extensive chemical decomposition and subsequent cathode failure. Due to anode re-oxidation concerns, the use of low pθ2 cathode firing during processing was explored by the inventors, and the results were not as would be expected from the priori art, and instead were highly positive;
(v) Re-oxidation of the cathode. The decomposition of the isostatically pressed LSCF structure in the low pθ2 cathode firing atmosphere followed by re- oxidation, resulted in a cathode with a structure which outperformed conventional LSCF cathodes. The reduction of the pressed structure followed by re-oxidation induced a proportion, structure and scale of porosity which significantly increased cathode triple-phase boundary length and hence cathode performance.
Although the exact structural and physical nature of the cathodes thus produced are not fully understood at present, the results achieved are a notable improvement over the prior art. Without wishing to be limited or bound by speculation, it is believed that a factor contributing to the lower temperature performance enhancement lies in the reduction of the cathode 'active' layer during cathode firing. The reaction produces a highly porous microstructure with porosity believed to be on the nano-scale. This microstructure possesses a vastly increased active surface area close to the electrolyte surface, and this increased specific surface area manifests itself as greatly reduced area specific resistance (ASR).
In other embodiments, the bi-layer cathode is fired under a dilute air Argon or air Nitrogen atmosphere.
In such embodiments, the bi-layer cathode can be fired in the pθ2 range of about 10"1- ICT10, for example in the pθ2 range of about lO^-lO"5.
The re-oxidisation step described for Process 1 need not be performed in such embodiments.
An example of a way in which the methods of the present invention can be used to make the fuel cell cathodes includes the following "Process 2" in which the following steps are performed: (i) As per Process 1 ; (ii) As per Process 1; (iii) As per Process 1;
(iv) The green bi-layer cathode is fired under a dilute air in diluent gas (such a diluent gas being Argon or Nitrogen) environment in the pθ2 range lO^-lO"10.
The additional advantage of this processing step as compared to step (iv) of Process 1 is that is occurs in a more oxidising environment, resulting in a greater number of ion vacancies in the cathode lattice, greater cathode conductivity, lower ASR and thus greater cell operating performance. In addition, it removes the need for a re-oxidation step (as in Process 1 step (v)), as this can occur when the fuel cell is first used without any degrading or structural risks associated with re-oxidation from a more reduced state.
Thus, there is no requirement for Process 1 step (v).
The method of the present invention produces a functional, bi-layer cathode possessing a unique and beneficial structure having a microporous structure in the current collector and active (i.e. primary) layers capable of performing well in the 500-600 0C operating temperature range. Cathodes processed by this route exhibited exceptional performance as shown in Figure 2, and when used with the metal supported IT-SOFC fuel cell of GB
2368450 they maintained their integrity throughout processing and subsequent fuel cell operation.
Notable advantages over the prior art achieved by the present invention include: (i) Previously unreported excellent cathode performance in the operating temperature range 500-600 0C; (ii) The preservation of metallic cell components and hence electrolyte integrity throughout cathode processing; and
(iii) The creation of a micro-porous cathode layer in direct contact with the electrolyte surface which significantly reduces ASR.
According to a second aspect of the present invention, there is provided a bi-layer fuel cell cathode comprising first and second layers, said first layer comprising LSCF, said second layer comprising a perovskite-based electrode, one of said first and second layers being isostatically pressed.
Such bi-layer fuel cell cathodes have a novel microstructure, an example of which is shown in Figure 1 and which, as detailed above, enables previously unreported and unexpectedly high performance in the 500-600 °C temperature range.
hi particular, the bi-layer fuel cell cathode can be made according to the method of the present invention. Also provided according to the present invention is a fuel cell incorporating a cathode according to the present invention.
The invention will be further apparent from the following description with reference to the several figures of the accompanying drawings which show, by way of example only, methods of manufacture of bi-layer fuel cell cathodes, and bi-layer fuel cell cathodes made according to same. Of the Figures:
Figure 1 shows a cross-sectional scanning electron microscope (SEM) image of a substrate-supported fuel cell comprising a bi-layer cathode structure, a dense electrolyte, a porous anode structure and a metal substrate. The top layer of the bi-layer cathode
structure is the current collector, and the layer underneath is the primary layer;
Figure 2 shows (bottom) a Cole-Cole plot of a conventional air fired LSCF cathode measured at 600° C, showing a relatively high ASR; and (top) Cole-Cole plots of two LSCF cathodes made according to the present invention - one (dashed line) fired in pθ2 of 10"17 and one (solid line) fired in pθ2 of 10'3, both measured at 600° C, showing significantly lower ASR values. X-axes show Z' (ohm). Y-axes show Z" (ohm); and Figure 3 shows the differing power densities obtained using a fuel cell of
GB 2368450 made with an LSCF cathode sintered at a ρθ2 of 10" 17 atm as per Process A (below) and for a LSCF cathode sintered at a pθ2 of 10"3 atm as per Process B (below). Data was obtained at 600 0C in wet 97% H2 and flowing air. X-axis shows current density (A cm' ); Y-axes show (left, for curves originating at
(0,0.9)) voltage (V), and (right, for curves originating at (0,0)) power density (W cm"2). Upper curve originating at (0,0.9) shows cathode at a pθ2 of 4x10"3 atm; lower curve originating at (0,0.9) shows cathode at a pθ2 of 10"17 atm; upper curve originating at (0,0) shows cathode at a pθ2 of 4xlO"3 atm; lower curve originating at (0,0) shows cathode at a pθ2 of 10"17 atm.
A symmetrical LSCF electrode half-cell on a CGO support was prepared by Process 1 and another by Process 2 (above).
Following the Process 1 route, the following process (Process A) was performed.
Firstly, an active LSCF layer of 5μm was screen-printed on a CGO electrolyte, and cold isostatic pressing to 50MPa performed. A 35μm current collector layer of LSCF was screen-printed on to define a bi-layer cathode, and the cathode assembly was fired in a H2O/H2 reducing atmosphere of 10"17 at 900° C for 1 hour. The cathode was subsequently heated in air at 700° C for 30 minutes prior to being used and measurement taking place.
Following the Process 2 route, involving firing in a slightly reducing atmosphere, the following process (Process B) was performed. Firstly, an active LSCF layer of 5μm was screen-printed on a CGO electrolyte, and cold isostatic pressing to 50MPa performed. A 35μm current collector layer of LSCF was then screen-printed on to define a bi-layer cathode, and the cathode assembly was fired in Ar/air reducing atmosphere of 10"3 at 900° C for 1 hour. No subsequent cathode conditioning in air was required.
Cole-Cole plots generated from the measurements of the cathodes (Figure 2, top) show the effect of these processing routes over a standard air fired LSCF cathode (Figure 2, bottom) (taken from measurements at 600° C for a LaQ.6Cao.4Fe0.8Coo.203 cathode on Ce0^SmC1O2-B electrolyte - Kilner JA, Lane JA, Fox H, Development and evaluation of oxide cathodes for ceramic fuel cell operation at intermediate temperatures, British Ceramic Proceedings, 1994, VoI: 52, Page: 268). The reducing atmosphere firing Z' measurements have been normalised to 8.52 ohm to provide consistency in presentation on the x-axis. This normalisation is required as the absolute values of the measurements depend on the substrate type, but the impedance response (and the resulting measurement changes) are only down to the electrode and are not affected by the substrate itself.
The results show ASR values of over 3 Ω/cm2 for the air fired cathode, less than 0.5 Ω/cm2 for the higher reducing firing and less than 0.15 Ω/cm2 for the slightly reducing atmosphere, thus showing the advantages of being able to fire LSCF cathodes in a partially reducing atmosphere.
Similar levels of ASR improvement have been produced on actual CGO electrolyte IT- SOFC fuel cells operating at 550-600° C. Figure 3 shows the results, with a maximum power density of 0.465 W/cm2 from the second cathode process compared to 0.32 W/cm2 from the first cathode process.
The structure of the cathodes obtained using Process A is shown in Figure 1. From top to bottom, the first (black) layer is air; the second layer is current collector; the third layer is the active (i.e. primary) layer; the second and third layers together define the bi-
layer cathode; the fourth layer is the dense CGO electrolyte; the fifth layer is the Ni- CGO anode; and the sixth (bottom) layer is the ferritic stainless steel substrate.
It will be appreciated that it is not intended to limit the present invention to the above examples only, many variants being readily apparent to a person of ordinary skill in the art without departing from the scope of the appended claims.
Claims
1. A method of producing a fuel cell cathode, the method comprising the steps of: (i) providing a primary layer comprising LSCF; (ii) isostatically pressing said primary layer in the pressure range 10-300
MPa; (iii) providing on said primary layer a current collecting layer comprising a perovskite-based electrode, to define a bi-layer cathode; and (iv) firing said bi-layer cathode in a reducing atmosphere.
2. A method according to claim 1, wherein said perovskite-based electrode comprises LSCF.
3. A method according to claim 1 or 2, said primary layer comprising an LSCF/CGO composite.
4. A method according to any of the preceding claims, said primary layer having a thickness of about 0.5-20 μm.
5. A method according to claim 4, said primary layer having a thickness of about 1-10 μm.
6. A method according to claim 5, said primary layer having a thickness of about 1.5-5 μm.
7. A method according to any of the preceding claims, said isostatic pressing being cold isostatic pressing.
8. A method according to any of the preceding claims, said isostatic pressing being performed at a pressure of about 10-300MPa.
9. A method according to claim 8, said isostatic pressing being performed at a pressure of about 20-100 MPa.
10. A method according to claim 9, said isostatic pressing being performed at a pressure of about 30-70 MPa.
11. A method according to any of the preceding claims, said current collecting layer having a thickness of about 5-100 μm.
12. A method according to claim 11, said current collecting layer having a thickness of about 10-70 μm.
13. A method according to claim 12, said current collecting layer having a thickness of about 30-50 μm.
14. A method according to any of the preceding claims, wherein said bi-layer cathode is fired at a temperature of about 700-900 0C.
15. A method according to claim 14, wherein said bi-layer cathode is fired at a temperature of about 800-900 0C.
16. A method according to any of the preceding claims, wherein said bi-layer cathode is fired in the pθ2 range of about 10"10-10"20.
17. A method according to claim 16, wherein said bi-layer cathode is fired under a dilute, buffered H2/H2O atmosphere.
18. A method according to any of the preceding claims, wherein said bi-layer cathode is re-oxidised after being fired in said reducing atmosphere.
19. A method according to claim 18, wherein said bi-layer cathode is re-oxidised at a temperature of about 700 0C.
20. A method according to any of claims 1-15, wherein said bi-layer cathode is fired under a dilute air Argon or air Nitrogen atmosphere.
21. A method according to claim 20, wherein said bi-layer cathode is fired in the ρθ2 range of about lO^-lO"10.
22. A method according to claim 21, wherein said bi-layer cathode is fired in the pθ2 range of about lO^-lO"5.
23. A method according to any of the preceding claims, wherein each of said layers is deposited by spray deposition or screen-printing.
24. A method of producing a fuel cell cathode substantially as hereinbefore described with reference to the accompanying drawings.
25. A fuel cell cathode produced by the method of any one of the preceding claims.
26. A bi-layer fuel cell cathode comprising first and second layers, said first layer comprising LSCF, said second layer comprising a perovskite-based electrode, one of said first and second layers being isostatically pressed.
27. A bi-layer fuel cell cathode according to claim 26, said first and second layers each comprising LSCF.
28. A fuel cell cathode substantially as hereinbefore described with reference to the accompanying drawings.
29. A fuel cell comprising a fuel cell cathode according to any of claims 25-28.
Priority Applications (8)
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EP06700946A EP1851815B1 (en) | 2005-01-25 | 2006-01-25 | Method of producing a fuel cell cathode |
US11/814,764 US20080318129A1 (en) | 2005-01-25 | 2006-01-25 | Fuel Cell Cathodes |
DK06700946.4T DK1851815T3 (en) | 2005-01-25 | 2006-01-25 | Process for producing a fuel cell cathode |
AT06700946T ATE537574T1 (en) | 2005-01-25 | 2006-01-25 | PRODUCTION PROCESS OF A FUEL CELL CATHODE |
ES06700946T ES2378525T3 (en) | 2005-01-25 | 2006-01-25 | Production method of a cathode for fuel cells |
CA2597997A CA2597997C (en) | 2005-01-25 | 2006-01-25 | Fuel cell cathodes |
US12/716,982 US20100159364A1 (en) | 2005-01-25 | 2010-03-03 | Fuel cell cathodes |
US13/630,183 US20130022898A1 (en) | 2005-01-25 | 2012-09-28 | Fuel cell cathodes |
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GB0501590.4 | 2005-01-25 | ||
GBGB0501590.4A GB0501590D0 (en) | 2005-01-25 | 2005-01-25 | Processing of enhanced performance LSCF fuel cell cathode microstructure and a fuel cell cathode |
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US12/716,982 Continuation US20100159364A1 (en) | 2005-01-25 | 2010-03-03 | Fuel cell cathodes |
US13/630,183 Continuation US20130022898A1 (en) | 2005-01-25 | 2012-09-28 | Fuel cell cathodes |
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EP (1) | EP1851815B1 (en) |
AT (1) | ATE537574T1 (en) |
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DK (1) | DK1851815T3 (en) |
ES (1) | ES2378525T3 (en) |
GB (1) | GB0501590D0 (en) |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2031679A2 (en) | 2007-08-31 | 2009-03-04 | Technical University of Denmark | Composite electrodes |
EP2131438A1 (en) | 2008-04-23 | 2009-12-09 | Ceres Intellectual Property Company Limited | Fuel cell module support |
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US8561535B2 (en) | 2010-02-27 | 2013-10-22 | Corning Incorporated | Method of screen printing on 3D glass articles |
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DE102016000799A1 (en) | 2016-01-27 | 2017-07-27 | Forschungszentrum Jülich GmbH | Process for the preparation of ceramic cathode layers on current collectors |
CA3117803A1 (en) * | 2018-10-30 | 2020-05-07 | Phillips 66 Company | Thermoelectrically enhanced fuel cells |
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2368450A (en) | 2000-10-25 | 2002-05-01 | Imperial College | Fuel cells |
US20020081762A1 (en) | 2000-10-10 | 2002-06-27 | Jacobson Craig P. | Electrochemical device and process of making |
US20040021240A1 (en) | 2002-07-31 | 2004-02-05 | Hancun Chen | Ceramic manufacture for a composite ion transport membrane |
US20040104519A1 (en) | 2002-11-29 | 2004-06-03 | Hancun Chen | Method of manufacturing an electrolytic cell |
Family Cites Families (66)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US645551A (en) * | 1899-03-11 | 1900-03-20 | Jasper N Clutter | Coal-gate for locomotive-tenders. |
US3645690A (en) * | 1968-01-22 | 1972-02-29 | Beckman Instruments Inc | Automated chemical analyzer |
US4296070A (en) * | 1980-06-16 | 1981-10-20 | Eastman Kodak Company | Slide distributor for a chemical analyzer |
JPH076992B2 (en) * | 1985-06-21 | 1995-01-30 | 富士写真フイルム株式会社 | Chemical analyzer |
DE3786087T2 (en) * | 1986-02-07 | 1993-09-16 | Fuji Photo Film Co Ltd | DEVICE FOR CHEMICAL ANALYSIS. |
US5154889A (en) * | 1986-08-07 | 1992-10-13 | Fuji Photo Film Co., Ltd. | Chemical analysis apparatus |
US4847208A (en) * | 1987-07-29 | 1989-07-11 | Bogen Steven A | Apparatus for immunohistochemical staining and method of rinsing a plurality of slides |
US5209903A (en) * | 1989-09-06 | 1993-05-11 | Toa Medical Electronics, Co., Ltd. | Synthetic apparatus for inspection of blood |
US5250262A (en) * | 1989-11-22 | 1993-10-05 | Vettest S.A. | Chemical analyzer |
US5595707A (en) * | 1990-03-02 | 1997-01-21 | Ventana Medical Systems, Inc. | Automated biological reaction apparatus |
US6472217B1 (en) * | 1990-03-02 | 2002-10-29 | Ventana Medical Systems, Inc. | Slide aqueous volume controlling apparatus |
US5225325A (en) * | 1990-03-02 | 1993-07-06 | Ventana Medical Systems, Inc. | Immunohistochemical staining method and reagents therefor |
US5425918A (en) * | 1990-07-18 | 1995-06-20 | Australian Biomedical Corporation | Apparatus for automatic tissue staining for immunohistochemistry |
US5244787A (en) * | 1991-01-31 | 1993-09-14 | Biogenex Laboratories | Antigen retrieval in formalin-fixed tissues using microwave energy |
US5273905A (en) * | 1991-02-22 | 1993-12-28 | Amoco Corporation | Processing of slide mounted material |
US5696887A (en) * | 1991-08-05 | 1997-12-09 | Biotek Solutions, Incorporated | Automated tissue assay using standardized chemicals and packages |
US5355439A (en) * | 1991-08-05 | 1994-10-11 | Bio Tek Instruments | Method and apparatus for automated tissue assay |
US5232664A (en) * | 1991-09-18 | 1993-08-03 | Ventana Medical Systems, Inc. | Liquid dispenser |
FI915731A0 (en) * | 1991-12-05 | 1991-12-05 | Derek Henry Potter | FOERFARANDE OCH ANORDNING FOER REGLERING AV TEMPERATUREN I ETT FLERTAL PROV. |
US5578452A (en) * | 1992-01-16 | 1996-11-26 | Biogenex Laboratories | Enhancement of immunochemical staining in aldehyde-fixed tissues |
US6180061B1 (en) * | 1992-05-11 | 2001-01-30 | Cytologix Corporation | Moving platform slide stainer with heating elements |
US5316452A (en) * | 1992-05-11 | 1994-05-31 | Gilbert Corporation | Dispensing assembly with interchangeable cartridge pumps |
US5645114A (en) * | 1992-05-11 | 1997-07-08 | Cytologix Corporation | Dispensing assembly with interchangeable cartridge pumps |
US5947167A (en) * | 1992-05-11 | 1999-09-07 | Cytologix Corporation | Dispensing assembly with interchangeable cartridge pumps |
US5439649A (en) * | 1993-09-29 | 1995-08-08 | Biogenex Laboratories | Automated staining apparatus |
US6632598B1 (en) * | 1994-03-11 | 2003-10-14 | Biogenex Laboratories | Deparaffinization compositions and methods for their use |
US5525514A (en) * | 1994-04-06 | 1996-06-11 | Johnson & Johnson Clinical Diagnostics, Inc. | Wash detection method for dried chemistry test elements |
AUPN038995A0 (en) * | 1995-01-05 | 1995-01-27 | Australian Biomedical Corporation Limited | Method and apparatus for human or animal cell sample treatment |
US5551487A (en) * | 1995-03-10 | 1996-09-03 | Hewlett-Packard Company | Micro-dispenser for preparing assay plates |
AUPN923596A0 (en) * | 1996-04-12 | 1996-05-09 | Australian Biomedical Corporation Limited | Method and apparatus for treatment of human or animal cell samples |
US5839091A (en) * | 1996-10-07 | 1998-11-17 | Lab Vision Corporation | Method and apparatus for automatic tissue staining |
US5804141A (en) * | 1996-10-15 | 1998-09-08 | Chianese; David | Reagent strip slide treating apparatus |
US5958341A (en) * | 1996-12-23 | 1999-09-28 | American Registry Of Pathology | Apparatus for efficient processing of tissue samples on slides |
US5948359A (en) * | 1997-03-21 | 1999-09-07 | Biogenex Laboratories | Automated staining apparatus |
US6489171B1 (en) * | 1997-04-18 | 2002-12-03 | Cell Marque Corporation | Chemical dispensing system and method |
US5985214A (en) * | 1997-05-16 | 1999-11-16 | Aurora Biosciences Corporation | Systems and methods for rapidly identifying useful chemicals in liquid samples |
US5922604A (en) * | 1997-06-05 | 1999-07-13 | Gene Tec Corporation | Thin reaction chambers for containing and handling liquid microvolumes |
US5882601A (en) * | 1997-06-18 | 1999-03-16 | Merck & Co., Ltd. | Deflected septum seal access port |
US6093574A (en) * | 1997-08-11 | 2000-07-25 | Ventana Medical Systems | Method and apparatus for rinsing a microscope slide |
CA2635001C (en) * | 1997-08-20 | 2012-12-04 | Ervin Essenfeld | High quality, continuous throughput, tissue fixation-dehydration-fat removal-impregnation |
US6649368B1 (en) * | 1997-10-24 | 2003-11-18 | Cell Marque Corporation | Composition and method for treating tissue samples |
US6269846B1 (en) * | 1998-01-13 | 2001-08-07 | Genetic Microsystems, Inc. | Depositing fluid specimens on substrates, resulting ordered arrays, techniques for deposition of arrays |
US6428752B1 (en) * | 1998-05-14 | 2002-08-06 | Affymetrix, Inc. | Cleaning deposit devices that form microarrays and the like |
JP3847559B2 (en) * | 1998-02-27 | 2006-11-22 | ベンタナ・メデイカル・システムズ・インコーポレーテツド | Automated molecular pathology device with independent slide heater |
US6855559B1 (en) * | 1998-09-03 | 2005-02-15 | Ventana Medical Systems, Inc. | Removal of embedding media from biological samples and cell conditioning on automated staining instruments |
US6183693B1 (en) * | 1998-02-27 | 2001-02-06 | Cytologix Corporation | Random access slide stainer with independent slide heating regulation |
US6096271A (en) * | 1998-02-27 | 2000-08-01 | Cytologix Corporation | Random access slide stainer with liquid waste segregation |
US6582962B1 (en) * | 1998-02-27 | 2003-06-24 | Ventana Medical Systems, Inc. | Automated molecular pathology apparatus having independent slide heaters |
US20030211630A1 (en) * | 1998-02-27 | 2003-11-13 | Ventana Medical Systems, Inc. | Automated molecular pathology apparatus having independent slide heaters |
US6495106B1 (en) * | 1998-03-24 | 2002-12-17 | Biogenex Laboratories | Automated staining apparatus |
US6248468B1 (en) * | 1998-12-31 | 2001-06-19 | Siemens Westinghouse Power Corporation | Fuel electrode containing pre-sintered nickel/zirconia for a solid oxide fuel cell |
US6544798B1 (en) * | 1999-02-26 | 2003-04-08 | Ventana Medical Systems, Inc. | Removal of embedding media from biological samples and cell conditioning on automated staining instruments |
US6673620B1 (en) * | 1999-04-20 | 2004-01-06 | Cytologix Corporation | Fluid exchange in a chamber on a microscope slide |
AU6079500A (en) * | 1999-07-08 | 2001-01-30 | Lee Angros | Antigen recovery and/or staining apparatus and method |
US6403036B1 (en) * | 1999-09-29 | 2002-06-11 | Ventana Medical Systems, Inc. | Temperature monitoring system for an automated biological reaction apparatus |
US6358473B1 (en) * | 1999-10-05 | 2002-03-19 | Albert Coello | Microscope slide heater |
US6403931B1 (en) * | 1999-10-07 | 2002-06-11 | Ventana Medical Systems, Inc. | Slide heater calibrator and temperature converter apparatus and method |
US6943035B1 (en) * | 2000-05-19 | 2005-09-13 | Genetix Limited | Liquid dispensing apparatus and method |
US6627159B1 (en) * | 2000-06-28 | 2003-09-30 | 3M Innovative Properties Company | Centrifugal filling of sample processing devices |
US7025933B2 (en) * | 2000-07-06 | 2006-04-11 | Robodesign International, Inc. | Microarray dispensing with real-time verification and inspection |
US6632554B2 (en) * | 2001-04-10 | 2003-10-14 | Hybrid Power Generation Systems, Llc | High performance cathodes for solid oxide fuel cells |
WO2003027041A1 (en) * | 2001-09-26 | 2003-04-03 | Ngk Insulators, Ltd. | Laminated ceramic sintered compact, method for producing laminated ceramic sintered compact, electrochemical cell, electroconductive joining member for electrochemical cell, and electrochemical device |
AU2003228709B2 (en) * | 2002-04-26 | 2006-12-21 | Ventana Medical Systems, Inc. | Automated molecular pathology apparatus having fixed slide platforms |
AU2003228791A1 (en) * | 2002-05-03 | 2003-11-17 | Battelle Memorial Institute | Cerium-modified doped strontium titanate composition for solid oxide fuel cell anodes and electrodes for other electrochemical devices |
USD495425S1 (en) * | 2003-03-24 | 2004-08-31 | Vision Biosystems, Limited | Cover tile |
US7770965B2 (en) * | 2003-04-09 | 2010-08-10 | Shane Zwezdaryk | Chair |
-
2005
- 2005-01-25 GB GBGB0501590.4A patent/GB0501590D0/en not_active Ceased
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2006
- 2006-01-25 ES ES06700946T patent/ES2378525T3/en active Active
- 2006-01-25 CA CA2597997A patent/CA2597997C/en active Active
- 2006-01-25 WO PCT/GB2006/000246 patent/WO2006079800A1/en active Application Filing
- 2006-01-25 AT AT06700946T patent/ATE537574T1/en active
- 2006-01-25 EP EP06700946A patent/EP1851815B1/en active Active
- 2006-01-25 DK DK06700946.4T patent/DK1851815T3/en active
- 2006-01-25 US US11/814,764 patent/US20080318129A1/en not_active Abandoned
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2010
- 2010-03-03 US US12/716,982 patent/US20100159364A1/en not_active Abandoned
-
2012
- 2012-09-28 US US13/630,183 patent/US20130022898A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20020081762A1 (en) | 2000-10-10 | 2002-06-27 | Jacobson Craig P. | Electrochemical device and process of making |
GB2368450A (en) | 2000-10-25 | 2002-05-01 | Imperial College | Fuel cells |
US20040021240A1 (en) | 2002-07-31 | 2004-02-05 | Hancun Chen | Ceramic manufacture for a composite ion transport membrane |
US20040104519A1 (en) | 2002-11-29 | 2004-06-03 | Hancun Chen | Method of manufacturing an electrolytic cell |
Non-Patent Citations (1)
Title |
---|
SAHIBZADA M ET AL: "Pd-promoted La0.6Sr0.4Co0.2Fe0.8O3 cathodes", SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 113-115, 1 December 1998 (1998-12-01), pages 285 - 290, XP004153308, ISSN: 0167-2738 * |
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Also Published As
Publication number | Publication date |
---|---|
CA2597997C (en) | 2013-06-25 |
US20080318129A1 (en) | 2008-12-25 |
ATE537574T1 (en) | 2011-12-15 |
US20130022898A1 (en) | 2013-01-24 |
EP1851815B1 (en) | 2011-12-14 |
CA2597997A1 (en) | 2006-08-03 |
GB0501590D0 (en) | 2005-03-02 |
ES2378525T3 (en) | 2012-04-13 |
EP1851815A1 (en) | 2007-11-07 |
US20100159364A1 (en) | 2010-06-24 |
DK1851815T3 (en) | 2012-04-02 |
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