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WO2005106999A1 - Joint amélioré avec application dans les dispositifs éléctrochimiques - Google Patents

Joint amélioré avec application dans les dispositifs éléctrochimiques Download PDF

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Publication number
WO2005106999A1
WO2005106999A1 PCT/US2005/014344 US2005014344W WO2005106999A1 WO 2005106999 A1 WO2005106999 A1 WO 2005106999A1 US 2005014344 W US2005014344 W US 2005014344W WO 2005106999 A1 WO2005106999 A1 WO 2005106999A1
Authority
WO
WIPO (PCT)
Prior art keywords
joint
ceramic
flexible gasket
stainless steel
metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2005/014344
Other languages
English (en)
Inventor
Scott K. Weil
John S. Hardy
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Battelle Memorial Institute Inc
Original Assignee
Battelle Memorial Institute Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US11/112,122 external-priority patent/US7794170B2/en
Application filed by Battelle Memorial Institute Inc filed Critical Battelle Memorial Institute Inc
Publication of WO2005106999A1 publication Critical patent/WO2005106999A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/02—Details
    • H01M8/0271—Sealing or supporting means around electrodes, matrices or membranes
    • H01M8/028—Sealing means characterised by their material
    • H01M8/0282—Inorganic material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/02—Sealings between relatively-stationary surfaces
    • F16J15/06—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces
    • F16J15/064—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces the packing combining the sealing function with other functions
    • F16J15/065—Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces the packing combining the sealing function with other functions fire resistant
    • 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
    • H01M2008/1293—Fuel cells with solid oxide electrolytes
    • 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

  • This invention relates to electrochemical devices, including, without limitation, solid oxide fuel cells, oxygen separators, and hydrogen separators. More specifically, the present invention relates to improved joints utilized in electrochemical devices, and methods of forming those joints.
  • YSZ layer In a planar design, this means that the YSZ layer must be dense, must not contain interconnected porosity, and must be connected to the rest of the device with a high temperature, gas-tight seal of the type shown in Figure 1.
  • One of the fundamental challenges in fabricating pSOFCs is how to effectively seal the thin electrochemically active YSZ membrane against the metallic body of the device creating a hermetic, rugged and stable stack. Typical conditions under which these devices are expected to operate and to which the accompanying YSZ-to- metal seal will be exposed include: (1 ) an average operating temperature of 750°C; (2) continuous exposure to an oxidizing atmosphere on the cathode side and a wet reducing gas on the anode side; and (3) an anticipated device lifetime of 10,000+ hours.
  • the sealing material typically barium aluminosilicate-based, reacts with the chromium- or aluminum oxide scale on the faying surface of the interconnect and forms a mechanically weak barium chromate or celsian phase along this interface as described in Z.G. Yang, K.S. Weil, K.D. Meinhardt, J.W. Stevenson, D.M. Paxton, G.-G. Xia, D.-S.
  • the technique differs from traditional active metal brazing in two important ways: (1 ) it utilizes a liquid-phase oxide-noble metal melt as the basis for joining and therefore exhibits high-temperature oxidation resistance and (2) the process is conducted directly in air without the use of fluxes and/or inert cover gases.
  • the strength of the bond formed during air brazing relies on the formation of a thin, adherent oxide scale on the metal substrate.
  • the technique employs a molten oxide that is at least partially soluble in a noble metal solvent to pre-wet the oxide faying surfaces, forming a new surface that the remaining molten filler material easily wets.
  • a number of metal oxide-noble metal systems are suitable, including Ag-CuO, Ag-V 2 0 5 , and Pt-Nb 2 Os as described in Z.B. Shao, K.R. Liu, L.Q. Liu, H.K. Liu, S. Dou (1993) Equilibrium phase diagrams in the systems PbO-Ag and CuO-Ag, J. Am. Cer. Soc, 76 (10) 2663-4, A.M. Meier, P.R. Chidambaram, G.R. Edwards (1995) A comparison of the wettability of copper- copper oxide and silver-copper oxide on polycrystalline alumina, J. Mater. Sci., 30 (19) 4781-6, and R.S. Roth, J.R.
  • a hostile operating environment such as an opeting environment where one side of the joint is continuously exposed to an oxidizing atmosphere and the other side is continuously exposed to a wet reducing gas.
  • the joint of the present invention is formed of a metal part 1 , a ceramic part 2, and a flexible gasket 3.
  • One side of the flexible gasket 3 is attached to the metal part 1 to form a hermetic seal between the two.
  • the other side of the flexible gasket 3 is bonded to the ceramic part 2 to form a separate hermetic seal between the flexible gasket 3 and the ceramic part 2.
  • the flexible gasket 3 is made of metal, preferably the a high temperature oxidation resistant metal with a coefficient of thermal expansion between that of metal part 1 and ceramic part 2. However, the flexible gasket 3 is thinner and more flexible than the metal part 1. As the joint is heated and cooled, differences in the material's coefficient of thermal expansion cause the ceramic part 2 and metal part 1 to expand and contract at different rates.
  • the flexible gasket 3 is thus configured to flex in response to these changes in temperature, up to and including changes in temperature in excess of 600° C while maintaining a hermetic seal between the ceramic part 2 and the flexible gasket 3, and between the metal part 1 and the flexible gasket 3.
  • the flexible gasket 3 has greater flexibility than the metal part 1.
  • the joint of the present invention preferably utilizes bonds between the ceramic part 2 and the flexible gasket 3 formed of brazed silver copper oxide alloys in air. Suitable bonds may also be formed by thin films of suitable glasses, such as those disclosed in US Patent No. 6,430,966, and polymeric pre-ceramic precursor such as those disclosed in C.A. Lewinsohn and S. Elangovan, Ceramic Engineering and Science Proc. Vol. 24, American Ceramic Soc, p. 317, (2003).
  • the bond between the flexible gasket 3 and the metal part 1 may also be formed of brazed silver copper oxide alloys in air. Alternatively, any means conventionally used to bond metal parts, such as welding, may be utilized.
  • the joint of the present invention finds particular utility in applications including, but not limited to, electrochemical devices such as solid oxide fuel cells (SOFCs), oxygen separators, and hydrogen separators.
  • SOFCs solid oxide fuel cells
  • oxygen separators oxygen separators
  • hydrogen separators hydrogen separators
  • the ceramic part 2 is an electrolyte.
  • the ceramic when utilized in certain SOFCs, it is preferred that the ceramic be an electrolyte formed of yttria stabilized zirconia (YSZ).
  • YSZ yttria stabilized zirconia
  • the flexible gasket 3 be formed of a high temperature stainless steel, thus allowing more flexibility in choosing the alloy for metal part 1.
  • the stainless steel used for the flexible gasket 3 may be an alumina forming stainless steel, a chromia forming stainless steel, or a superalloy
  • the metal part 1 may be an alumina forming stainless steel, a chromia forming stainless steel, or a superalloy.
  • Figure 1 is an illustration of a typical configuration of a solid oxide fuel cell used in a solid oxide fuel cell stack.
  • Figure 2 is an illustration of the joint of the present invention showing the arrangement of the metal part, the ceramic part, and the flexible gasket.
  • Figure 3 is a composite cross-sectional micrograph of a joint fabricated in proof of principle experiments to demonstrate the present invention.
  • Figure 4 is a graph showing the rupture strength of the joints fabricated in proof of principle experiments to demonstrate the present invention in the as-joined and as-cycled conditions.
  • a number of high temperature alloys were considered for use as the metal gasket in experiments conducted to demonstrate joints of the present invention.
  • the initial materials screening analysis focused on four key properties: high oxidation resistance, low stiffness, high ductility, and low cost. Based on these factors, a commercial alumina- forming ferritic steel was selected as the foil membrane: DuraFoil (22% Cr, 7% Al, 0.1 %La+Ce, bal. Fe, manufactured by Engineered Materials Solutions, Inc. Attleboro, Mass). The DuraFoil was supplied as 50 ⁇ m thick sheet.
  • Each foil washer was bonded to a 6.2mm thick Haynes 214 washer, with an outside diameter of 4.4cm and an inside diameter of 1.5cm, using BNi-2 braze tape purchased from Wall Colmonoy, Inc. Madison Heights, Ml.
  • Durafoil component to the Haynes 214 using BNi-2 braze tape.
  • a second ⁇ o . brazing operation was conducted by air brazing the top side of the stamped foil to the YSZ side of a 25mm diameter bilayer disc using a Ag-4mol% CuO paste.
  • Joining was conducted by applying a concentric 24mm ring of braze paste to the Durafoil washer using an automated pressure-driven dispenser. After allowing the paste to dry, the bilayer was placed YSZ-side down onto the washer and dead-loaded with 25g of weight. The assembly was heated in air at 20°C/min to 1050°C and held at temperature for 15min before furnace cooling to room temperature.
  • Thermal cycle testing was conducted by heating the specimens in air at a rate of 75°C/min to 750°C, holding at temperature for ten minutes, and cooling to ⁇ 70°C in forty minutes before re-heating under the same conditions. A minimum of six specimens was tested for each test condition. Microstructural analysis was conducted on polished cross-sectioned samples using a JEOL JSM-5900LV scanning electron microscope (SEM) equipped with an Oxford energy dispersive X-ray analysis (EDX) system.
  • SEM JEOL JSM-5900LV scanning electron microscope
  • EDX Oxford energy dispersive X-ray analysis
  • FIG. 3 Shown in Figure 3 is a composite cross-sectional micrograph of a joint according to the present invention.
  • the joint was well sealed, as determined by hermeticity testing conducted prior to metallographic analysis.
  • the entire seal between the metal gasket and the metal part is approximately 1.1 mm thick, although it is expected that this can be readily reduced simply by altering the geometry of the DuraFoil stamping.
  • the CuO-Ag braze forms a robust joint between the YSZ and the alumina scale of the DuraFoil. Note that the braze is thicker toward the center of the specimen.

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

Abstract

Un joint pour utilisation dans les dispositifs électrochimiques, tels que les cellules de combustible d'oxyde solides (SOFC), les séparateurs d'oxygène et les séparateurs d'hydrogène, qui va maintenir une étanchéité hermétique à des températures de fonctionnement supérieures à 600°C, malgré l'excès de cyclage thermique répété à 600°C dans un environnement de fonctionnement hostile où un côté du joint est continuellement exposé à une atmosphère oxydante et l'autre côté est continuellement exposé à un gaz réduisant l'humidité. Le joint est formé d'une partie en métal, d'une partie en céramique, et d'un raccord flexible. Le raccord flexible est en métal, mais est plus fin et plus flexible que la partie en métal. Lorsque le joint est chauffé et refroidi, le raccord flexible est configuré pour fléchir en réponse aux changements de la taille relative de la partie en métal et de la partie en céramique dus aux différences de coefficient de dilatation thermique de la partie en métal et de la partie en céramique, de telle sorte que toute la tension créée par les différences de dilatation et de contraction des parties en céramique et en métal soit absorbée et dissipée en fléchissant le raccord flexible.
PCT/US2005/014344 2004-04-27 2005-04-26 Joint amélioré avec application dans les dispositifs éléctrochimiques Ceased WO2005106999A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US56604504P 2004-04-27 2004-04-27
US60/566,045 2004-04-27
US11/112,122 2005-04-22
US11/112,122 US7794170B2 (en) 2005-04-22 2005-04-22 Joint with application in electrochemical devices

Publications (1)

Publication Number Publication Date
WO2005106999A1 true WO2005106999A1 (fr) 2005-11-10

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008016503A3 (fr) * 2006-08-02 2008-03-20 Corning Inc Pile a combustible a oxyde solide présentant une géométrie caractérisée par un joint allongé
WO2008109100A1 (fr) * 2007-03-08 2008-09-12 Corning Incorporated Revêtements conducteurs, matériaux de liaison et dispositif réalisés avec ces matériaux et procédés de production
KR20090063175A (ko) * 2007-12-13 2009-06-17 꼼미사리아 아 레네르지 아토미끄 전기화학 전지 시스템에 대한 초소성 밀봉 시스템
FR2925487A1 (fr) * 2007-12-24 2009-06-26 Commissariat Energie Atomique Dispositif de liaison souple etanche entre un substrat metallique et un substrat ceramique, application a l'etancheite d'electrolyseurs haute temperature
WO2009155184A1 (fr) * 2008-06-17 2009-12-23 Battelle Memorial Institute Joint d'étanchéité double de sofc présentant une commande dimensionnelle pour une stabilité supérieure pendant plusieurs cycles thermiques
US7691488B2 (en) * 2007-06-11 2010-04-06 Battelle Memorial Institute Diffusion barriers in modified air brazes

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0967672A (ja) * 1995-08-29 1997-03-11 Tokyo Gas Co Ltd フェライト系ステンレス鋼、これを使用した固体電解質燃料電池およびこのフェライト系ステンレス鋼の製造方法
US6430966B1 (en) * 1999-07-30 2002-08-13 Battelle Memorial Institute Glass-ceramic material and method of making
US20030132270A1 (en) * 2002-01-11 2003-07-17 Weil K. Scott Oxidation ceramic to metal braze seals for applications in high temperature electrochemical devices and method of making
US20040060967A1 (en) * 2002-09-27 2004-04-01 Zhenguo Yang Gas-tight metal/ceramic or metal/metal seals for applications in high temperature electrochemical devices and method of making

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0967672A (ja) * 1995-08-29 1997-03-11 Tokyo Gas Co Ltd フェライト系ステンレス鋼、これを使用した固体電解質燃料電池およびこのフェライト系ステンレス鋼の製造方法
US6430966B1 (en) * 1999-07-30 2002-08-13 Battelle Memorial Institute Glass-ceramic material and method of making
US20030132270A1 (en) * 2002-01-11 2003-07-17 Weil K. Scott Oxidation ceramic to metal braze seals for applications in high temperature electrochemical devices and method of making
US20040060967A1 (en) * 2002-09-27 2004-04-01 Zhenguo Yang Gas-tight metal/ceramic or metal/metal seals for applications in high temperature electrochemical devices and method of making

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 1997, no. 07 31 July 1997 (1997-07-31) *

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008016503A3 (fr) * 2006-08-02 2008-03-20 Corning Inc Pile a combustible a oxyde solide présentant une géométrie caractérisée par un joint allongé
WO2008109100A1 (fr) * 2007-03-08 2008-09-12 Corning Incorporated Revêtements conducteurs, matériaux de liaison et dispositif réalisés avec ces matériaux et procédés de production
US7691488B2 (en) * 2007-06-11 2010-04-06 Battelle Memorial Institute Diffusion barriers in modified air brazes
CN101459247A (zh) * 2007-12-13 2009-06-17 法国原子能委员会 优选用于电化学电池系统的超塑性密封结构系统
EP2071216A1 (fr) * 2007-12-13 2009-06-17 Commissariat à l'Energie Atomique Joint d'étanchéité superplastique, de préférence pour système à cellules électrochimiques
FR2925140A1 (fr) * 2007-12-13 2009-06-19 Commissariat Energie Atomique Joint d'etancheite superplastique, de preference pour systeme a cellules electrochimiques
KR20090063175A (ko) * 2007-12-13 2009-06-17 꼼미사리아 아 레네르지 아토미끄 전기화학 전지 시스템에 대한 초소성 밀봉 시스템
US8246056B2 (en) 2007-12-13 2012-08-21 Commissariat A L'energie Atomique Superplastic sealing system, preferentialy for electrochemical cell system
CN101459247B (zh) * 2007-12-13 2013-11-27 法国原子能委员会 优选用于电化学电池系统的超塑性密封结构系统
KR101580833B1 (ko) 2007-12-13 2015-12-29 꼼미사리아 아 레네르지 아또미끄 에 오 에네르지 알떼르나띠브스 전기화학 전지 시스템에 대한 초소성 밀봉 시스템
FR2925487A1 (fr) * 2007-12-24 2009-06-26 Commissariat Energie Atomique Dispositif de liaison souple etanche entre un substrat metallique et un substrat ceramique, application a l'etancheite d'electrolyseurs haute temperature
WO2009083539A1 (fr) * 2007-12-24 2009-07-09 Commissariat A L'energie Atomique Liaison souple etanche entre un substrat metallique et un substrat ceramique, procede de realisation d'une telle liaison, application du procede a l'etancheite d'electrolyseurs haute temperature et des piles a combustible
US8424878B2 (en) 2007-12-24 2013-04-23 Commissariat A L'energie Atomique Et Aux Energies Alternatives Sealed flexible link between a metal substrate and a ceramic substrate, method for making such a link, application of the method to sealing high temperature electrolyzers and fuel cells
WO2009155184A1 (fr) * 2008-06-17 2009-12-23 Battelle Memorial Institute Joint d'étanchéité double de sofc présentant une commande dimensionnelle pour une stabilité supérieure pendant plusieurs cycles thermiques

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