Structure of sealed joint unit for electrochemical device

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional U.S. Patent Application №60 / 632,015, filed Nov. 30, 2004, entitled "NODE CONNECTIONS seal structure for an electrochemical device."

details of government support

This invention was made with government support under contract DE-AC02-05CH11231, provided by the Ministry of Energy of the United States Board of the University of California for the administration and management of Lawrence Berkeley National Laboratory. The Government has certain rights to this invention.

FIELD OF THE INVENTION

The present invention relates to compounds of the compacted assembly for high temperature electrochemical devices such as solid oxide fuel cells, in particular of modular assemblies of parallel series connected electrochemical cells. Node Connection provides a seal, structural integrity, as well as electrical connection and isolation.

BACKGROUND OF THE INVENTION

Solid state electrochemical devices are normally cells that include two porous electrodes - an anode and a cathode, and a dense solid electrolyte membrane disposed between the electrodes. In the case of a typical solid oxide fuel cell anode is exposed to fuel and the cathode is exposed to an oxidant in separate closed systems to avoid any mixing of the fuel and oxidants due to the exothermic reactions that can occur when using the hydrogen fuel.

In applications SOFC electrolyte membrane typically consists of a ceramic oxygen ion conductor. In other embodiments, the types of devices for separating gas solid membrane may be made from a mixed ionic-electronic conducting material ("MIEC"). A porous anode may be a layer of ceramic, metal or ceramic-metal composite ("cermet") that is in contact with the electrolyte membrane on the fuel side of the cell. The porous cathode is typically a metal oxide layer with a mixed ion-electronic conductivity (MIEC) metal oxide or a mixture of an electronically conductive (or MIEC metal oxide) and a metal oxide ion conductivity.

The operating temperature of solid oxide fuel cells generally varies between about 900 ° C and about 1000 ° C to maximize the ionic conductivity of the electrolyte membrane. At corresponding temperatures the oxygen ions easily migrate through the crystal lattice of the electrolyte.

Since each fuel cell generates a relatively small voltage, to increase the capacity of the system may combine several fuel cells. Such matrices or assemblies usually have a tubular or planar design. Generally planar structures have planar anode, electrolyte and cathode deposited on a conductive interconnect and collected by the serial connection. However, generally planar structure characterized by significant problems in terms of safety and reliability due to the complexity of sealing units and acquisition planar assembly. Tubular designs utilizing long porous support tubes with electrodes and electrolyte layers, deposited on the carrier tube, can reduce the number of seals required by the system. Fuel or oxidants are directed through channels in the tube or around the exterior surface of the tube.

Efficiency of high-temperature electrochemical devices (operating at temperatures above 800 ° C, for example between about 900 ° C and 1000 ° C) is limited by the quality and reliability of the seals that join multiple cells to one another, or individual cells with a casing or sets of cells. Typically, the seals must perform one or more of the following features: the mutual separation of oxidizer, fuel and process gas, containment gases in the device, the adhesion between the sealed surfaces, and electrical connection or insulation. Of course, the seal material must not be a source of contamination for the other materials in the system. Performing all these functions for one material at elevated temperature in oxidizing, reducing, or corrosive environments is difficult.

As possible for use in high temperature electrochemical devices have been considered many types of sealing materials, including ceramic adhesives, glass, brazing materials and mica compressible seal. Each of these materials has limitations that prevent the implementation of all the necessary requirements. Ceramic adhesives tend to be porous and do not possess the gas barrier. Glasses provide a good seal at the initial stage of use, but have a short lifetime due to cracking caused by thermal stresses and the chemical reaction with the joined surfaces. Solid solders are expensive and have conductivity. Mica compressible seal often have a high leakage rate and a short life due to cracking.

Thus, a need exists for an improved sealed joint for electrochemical node devices.

SUMMARY OF THE INVENTION

The present invention utilizes a combination of materials in a compact structure that allows to provide all the necessary functions for connection node high-temperature electrochemical devices. It is also proposed a method of forming the node connections. Node Connection provides a seal, structural integrity, as well as electrical connection and isolation.

According to the subject invention, the connection node includes: sections that provide traction elements connecting to one another; one or more seal sections that provide gas-tightness; and sections providing electrical connection and / or electrical insulation between the connecting member. Furthermore, each of the sections may be subjected to treatment or it may be coated to increase the life of these sections. Connection of a durable, gas tight and provides control of electrical characteristics in a wide temperature range. Host compounds can be used in high-temperature electrochemical devices such as solid oxide fuel cells.

An important feature of the invention is the partial or complete separation of the various functions of the connection node, providing the possibility of combining the materials and methods appropriate to each function unit to create the compound satisfies all the functional requirements and containing all the functional materials in a compact volume. Traditionally, the various functions of the node connections require physical separation of the functional objects. Compact node compounds described herein, should be inexpensive and easy to manufacture and is intended for a compact multi-cell structure.

Some particularly efficient features and techniques of specific embodiments of the invention described further below, include the selection of the thickness of the braze and insulating material, to approximate the overall coefficient of thermal expansion of the composite insulating member (comprising solder and the insulating material, as shown in Figure 2) to the coefficient of thermal expansion of the cell components. In addition, roughening the surface of the metal casing assembly compound in contact with the insulating member (D) node compounds can enhance knot strength compound. In some cases the effect may have a replacement in the brazing connections at the node structure sintering metal to metal.

A suitable configuration of the node connection for an electrochemical device has a metal casing junction node, a first porous electrode, a second porous electrode separated from the first porous electrode solid electrolyte, and an insulating member disposed between the metallic casing junction node and the electrolyte and between the metal casing junction node and a second electrode . One or more portions of solid solder structurally and electrically connects the first electrode with a metal casing and forms a connection node tight seal between the first electrode and the second electrode.

BRIEF DESCRIPTION OF DRAWINGS

1 illustrates the general features of the compacted assembly compound according to the present invention when used in the assembly of solid oxide fuel cells.

2 and 3 - the cross-sections of densified nodes compound according to alternative embodiments of the present invention, when used in the assembly of solid oxide fuel cells.

Figure 4 - the cross-sectional photomicrograph of dense insulator brazed fastened, according to one aspect of the present invention obtained by an optical microscope.

DISCLOSURE OF THE INVENTION

Next, detailed reference will be made to the specific embodiments of the invention. Examples of specific embodiments are illustrated in the accompanying drawings. Description of the invention will be conducted with reference to specific exemplary embodiments, it is obvious that the invention is not limited to such specific embodiments. On the contrary, it is expected to apply to variations, modifications and equivalents that may be included in the invention within the scope of the appended claims. In the following description, numerous specific details are considered in order to ensure a complete understanding of the present invention. The present invention may be practiced without some or all of these specific details. In other instances, well-known processing steps are not discussed in detail herein so as not to obscure the present invention.

The invention includes several members forming junction node, wherein the various elements have different functions. Node compound is effective to connect a plurality of cells (generally tubular modules) of an electrochemical device when creating, for example, an assembly of serially connected segments mnogoyacheykovyh. Node connection will be described in the context of this embodiment, but it is assumed that this example is illustrative and does not limit the scope of applicability of the invention.

A suitable configuration of the node connection for an electrochemical device according to the present invention has a metal casing junction node, a first porous electrode, a second porous electrode separated from the first porous electrode solid electrolyte, and an insulating member disposed between the metallic casing junction node and the electrolyte and between the metal casing junction node and a second electrode. One or more portions of solid solder structurally and electrically connect the first electrode with a metallic jacket and form junction node tight seal between the first electrode and the second electrode.

1 illustrates some general hallmarks node compounds according to the present invention. Functions node compound include providing mechanical joining of neighboring cells, sealing of cells prevents mixing atmosphere 1 and atmosphere 2, electrical connection between neighboring cells, and electrical insulation of the electrodes of one cell from one another. One preferred configuration for the node connections depicted in Figure 1. However, other configurations that perform the same function, without departing from the scope of the invention. 2, 3 and 4 provide further illustrate the specific characteristics of the nodes of a compound according to the present invention. Functions and features of the various elements of node connections discussed below.

As used in the fuel cell electrochemical cells generally comprise an ion-conducting electrolyte, pa zmeschenny between the porous anode and the cathode. The fuel cell used as an example of an electrochemical cell for illustrative purposes, but it is obvious that the electrochemical cell can be a generator of oxygen, synthesis gas generator or apparatus for separating hydrogen gas and the like.

Electrochemical cells may be provided with a carrier anode or cathode with a carrier-supported electrolyte. Electrochemical cell with electrode carriers may have electrode substrate is a ceramic, ceramic-metal composite (cermet) or metal alloy. In one embodiment, the cells are made in the form of double layers of type Ni-YSZ / YSZ or LSM / YSZ and the counter electrode, caused after high-temperature sintering of the double layer. In another embodiment, all three layers are applied and then subjected to sintering them by a high temperature treatment in one step. For example, triple layers of LSM / YSZ / LSM or LSM / YSZ / Ni-YSZ can be sintered in one step.

Furthermore, it should be apparent that the structure carrying the electrodes may also be multi-layered or structures with smoothly varying distribution profile of the impurity composed of different materials and / or microstructures and not simply be a homogeneous electrode. For example, the carrier structure with the cathode can be a substrate of porous LSM, obtained by molding or extrusion molding, on which a layer of porous LSM + YSZ, and this layer is deposited YSZ electrolyte film and the counter electrode. In another embodiment, the porous catalyst layer type Ni-YSZ can be placed between the porous layer-type alloy ferritic steel and YSZ electrolyte layer type.

The preferred height of the electrochemical cell is determined by the conductivity of the electrode layers. For structures with a ceramic substrate is preferably an electrochemical cell height varies between approximately 1 cm and about 5 cm. The electrochemical cell structures with metal substrate preferably varies between cell height of about 2 cm and about 10 cm.

In embodiments, the carrier with the cathode in the cathode electrode is preferably a cylindrical or rectangular tube having a thickness in the range from about 100 microns to about 3000 microns.

However, particularly preferred are the cathode layers with a thickness ranging between about 150 microns and about 2000 microns. In electrochemical cells with anode supported preferred cathode is deposited as a thin film on one surface and forming as a result of coupling the cathode electrode having a thickness ranging between about 50 microns and about 1500 microns. Obviously, the selected thickness of the electrode tubes and electrolyte can vary depending on the thermal expansion, as well as the characteristics of electronic conductivity and ionic conductivity of the electrolyte and electrode materials.

Among suitable materials cathode electrodes according to the present invention can be called cermets, ceramics and metals. For example, suitable ceramic components include: La1-xSrxMnyO3-δ (1≥X≥0,05) (0,95≤u≤1,15) ("LSM") (δ is defined as the value that expresses a small deviation from the exact stoichiometry), La1-xSrxCoO3-δ. (1≥H≥0,10) ("LSC"), La1-xSrxFeyO3-δ (1≥X≥0,05) (0,95≤u≤1,15) ("LSF"), SrCo1-xFexO3- δ (0,30≥X≥0,20), La0,6Sr0,4Co0,6Fe0,4O3-δ, Sr0,7Se0,3MnO3-δ, LaNi0,6Fe0,4O3-δ, Sm0,5Sr0,5SoO3-δ, silica Zirconia stabilized with yttria (YSZ), zirconia stabilized by scandium oxide (SSZ), (CeO2) 0.8 (Gd2O3) 0.2 (CGO), LaO0,8Sr0,2Ga0,85Mg0,15O2,825 (LSGM20-15 ), (Bi2O3) 0.75 (Y2O3) 0.25 and `alumina.

Preferred materials include LSM La0,8Sr0,2MnO3, La0,65Sr0,30MnO3-δ and La0,45Sr0,55MnO3-δ. Suitable metal components, including for the cermets, are transition metals, Cr, Fe, Ag and / or alloys such as nizkohromistye ferritic steel type 405 and 409 (with 11-15% Cr), intermediate ferritic steel with a chromium content type 430 and 434 (with 16-18% Cr), high-chromium ferritic steel of type 442, 446 and E-Brite (with 19-30% Cr), chrome-based alloys such Cr5FelY chromium alloys and nickel-based alloys such Ni20Cr Inconel, in including Inconel 600 (Ni 76%, 15,5% Cr, 8% Fe, 0.2% Cu, 0.2% Si, 0.5% Mn and 0.08% C).

A very thin layer of electrolyte is preferably applied to the cathode tube. It has been shown that the operating temperature of the electrochemical cell can be reduced by the use of thin film ceramic electrolytes and electrodes by reducing ohmic losses in ionic and ionic-electronic conducting materials deposited as thin films. Then, in one embodiment, a double layer is subjected to co-firing to obtain free of pinholes solid electrolyte film with good adhesion to the porous structure of the electrode. When selecting materials, the electrolyte and the electrodes must also take into account the mode of sintering materials and film and substrate. For example, depending on the nature of the selected electrode material may be necessary in the implementation of the second electrode when the firing temperature different from that used to give the electrolyte sufficient density to prevent the passage of gases through the electrolyte layers or the temperature used for processing the first electrode.

Among several techniques of obtaining thin films known to those skilled in the art, it may be called the methods of physical vapor deposition, calendaring, sol-gel deposition, sputtering, colloidal deposition, centrifugal casting, slip casting, tape casting, extrusion, screen printing, deposition coating with a brush, film transfer, co-extrusion, electrophoretic deposition, dip coating, aerosol spray, vacuum infiltration, plasma deposition, electrochemical deposition, and many other methods known to those skilled in the art. Preferred are coating by immersion, spray, aerosol and screen printing. Generally to adhere to the porous support and densification of the electrolyte layer requires heating to a sufficient temperature.

There are many methods of creating thin films, but is preferably a colloidal deposition method. In this embodiment, the electrolyte material is typically prepared as a suspension of the powder material in liquid media such as water, isopropanol or other suitable organic solvents. The suspension may be coated on the surface of the electrode layer in many ways; for example, aerosol spray, dip coating, electrophoretic deposition, vacuum infiltration or by tape-casting. Typically, the target unfired oxide film is deposited as colloidal particles at the burnt or partially fired substrates. Furthermore, the film should have good adhesion to the surface of the substrate without excessive infiltration into the pores of the electrode, and the polarization at the interface between the electrolyte and the electrode should be minimal.

Preference colloidal process because it is inexpensive and scalable, and allows the production of devices with high performance at reduced temperatures. However, colloidal deposition of dense electrolyte layers on porous substrates requires the chemical compatibility of the materials at the processing temperature and sufficient matching of thermal expansion coefficients between the layers.

To ensure low overpotential during device operation are generally preferred are free of pinholes and cracks dense electrolyte layer 30, the thickness of which ranges from about 1 micron to about 50 microns, on electrode substrates of high porosity and suitable microstructure. The preferred thickness of the electrolyte layer for a typical fuel element ranges from about 10 microns to about 30 microns.

The material in the electrolyte is preferably a thin layer of metal oxide powder (ceramic) type zirconia stabilized with yttrium oxide (YSZ), for example, (ZrO2) x (Y2O3) y where (0,88≥H≥0,97) and (0,03≤U≤0,12). The preferred material is (ZrO2) 0.92 (Y2O3) 0.08 or (ZrO2) 0.90 (Y2O3) 0,10, available on the market. Other possible electrolyte materials include (Z rO2) 0,9 (Sc2O3) 0,1 - zirconia stabilized with scandium oxide (SSZ), (CeO2) 0,8 (Gd2O3) 0,2 (CGO), La0,8Sr0 , 2Ga0,85Mg0,15O2,825 (LSGM20-15) and (Bi2O3) 0.75 (Y2O3) 0.25. In another embodiment, the electrolyte material may be a mixed ionic-electronic conductor, for example SrCo1-xFeXO3-δ (0,30≥X≥0,20), La0,6Sr0,4Co0,6Fe0,4O3-δ, Sm0,5Sr0,5CoO3 and La1-xSrxCoO3-δ. Such structures may also be used, for example, in devices for oxygen separation.

The anode electrode electrochemical cell with a cathode carrier in a preferred embodiment is a thin film having a thickness from about 50 microns to 500 microns. However, preferred are electrode layers having a thickness ranging between about 150 microns and about 300 microns. In electrochemical cells with anode supported preferred anode is a tube with a thickness ranging between about 250 microns and about 2500 microns.

Materials of electrodes and electrolyte are preferably matched and the thickness of the applied materials may be selected based on the characteristics of thermal expansion, electronic conductivity and ionic conductivity of the electrode materials and electrolyte, and interconnect materials. Further, the thickness of the film of electrolyte may depend on the electrolyte and gas barrier material capabilities to maintain its mechanical integrity e.g., resist cracking when exposed to temperatures in the range between the operative and inoperative states.

Metal compounds housing assembly may be made of inexpensive ferritic steel, the coefficient of thermal expansion which is matched with the typical electrode and electrolyte materials. Among the metals used for the metal jacket assembly compound can be named: Ni, Cu, alloys containing Ni, Ni based superalloys, alloys containing Cu, alloys containing Fe, stainless steel, Fe based alloys containing Cr, alloys Fe- Cr containing reactive element type Y or La, austenitic steels of type AISI 304 or 316, ferritic steel type AISI 430 or 446, alloys containing Al, Fe-Cr alloy containing A1 and a reactive element of Y-type alloys, Fe-Cr comprising 0.1-3.0 wt.% Mn, Fe-Cr alloys containing 12-30 wt.% Cr, Cr-Fe alloys containing 16-26 wt.% Cr, Fe based alloys containing 18 22 wt.% Cr, with 0.5-2.0 wt.% Mn and 0.1-1.0 wt.% Y and others. It is also possible modification of part or the whole surface of the metal by sol-gel deposition, vapor deposition, plasma spray, plating, or any other method known to those skilled in the art.

As shown in Figure 1, a single cell comprises Electrode 1, Electrode 2 and electrolyte. Electrodes 1 and 2 must be electrically insulated from one another. Electrode 1 is electrically connected to the electrode 2 of the previous cell; Electrode 2 is electrically connected to one electrode of the next cell. Node connection illustrated in Figure 1 also includes the following features:

Metal casing assembly compound: forming a support structure for a junction node, and also provides an electrical connection between adjacent cells as described above. Roughening the surface of the metallic cylinder contacting the insulating member (D), improves the strength of the connection node in certain embodiments (e.g., where the insulator is an adhesive). Not required for the surface roughness of the insulator, fastened brazing.

A. Among the various roughening methods can be called sand blasting, chemical etching, metal powder and napekaniem knurling.

B. Solid solder: provides adhesion and electrical connection between the electrode 1 and the metal casing (A), and the seal prevents mixing atmosphere 1 (electrode 1) and Atmosphere 2 (electrode 2). Preferred are brazing filler metals based on alloys of Ar, Au, Cu or Ni or a mixture of ceramic-type alumina, silica or titanium dioxide, or with a more preferred particulate or fibrous braze filler having a thermal expansion coefficient not exceeding 6 × 10- 6 1 / K (e.g., titanite aluminum / magnesium or zirconium wolframite). Brazing can be applied as preforms such as wires or foil or as pastes or inks. Applying a paste or paint is usually carried out by syringe, spray, brush, roller, by pouring or screen printing.

S.Zaschitnoe coating for brazing: 1 reduces the effects of the atmosphere in the brazing material (B). This is particularly important in the case where one atmosphere is oxidizing or corrosive. Protective coating for brazing can be made of ceramic adhesive, glass frit, etc. This stability brazing (B) under the protective cover 1 for brazing is required.

D. Insulating member: prevents a short circuit by providing insulation between the electrode 2 and the metal casing (A) of the node connection. Using non-porous insulating element prevents mixing atmosphere 1 and atmosphere 2 Coupling insulating member with a metal casing (A) of the connection node and the electrode 2 and / or electrolyte facilitates the mechanical connection with the metal casing element (A) of the node connection. As the insulating member may be used a variety of materials, including adhesives based on ceramic or glass, dense or porous ceramic member that can be secured by fitting or brazing or glass element.

Metal casing connection node of one cell may be connected to the preceding cell, that is brazed to create a plurality of serially connected cells (construction of series connected segments). As shown in Figure 1, in the case of a porous insulating member only brazing material (B) provides gas impermeability. In the case of a dense insulating member itself insulator is also involved in ensuring gastightness. For example, a glass insulator (e.g., glasses based on SiO2 or Al2O3 / SiO2) may be adhered to the cell and the metal case (A) of the node connection or a ceramic insulator (e.g., Al2O3) can be brazed to the metallic housing assembly compound and cell, as shown in Figures 2 and 4.

In this embodiment, the electrolyte is contacted brazing. This can be a source of weakness, as thermal expansion coefficient mismatch between the braze and electrolyte can cause cracking of the electrolyte and mixing atmospheres 1 and 2. A modification of the composition of the electrolyte layer for reinforcement or a layer of a complete replacement of the more resistant material near the junction node. For example, in the case of electrolyte of zirconia stabilized with yttria (YSZ), a certain amount of Al2O3 may be mixed with the electrolyte during cell formation. This somewhat reduces the conductivity of the electrolyte, but can significantly improve the resistance to cracking. In another embodiment, the composition of the electrolyte can vary from YSZ-rich in the cell to Al2O3-rich region near the braze.

Components of the cell and the metal casing (A) a compound selected node such that they have similar coefficients of thermal expansion (CTE). This reduces the thermal stress on the device, especially when sudden changes in temperature, such as when turning. For example, SOFC (solid oxide fuel cells) all the components matched in CTE with an electrolyte (i.e. 10,5 × 10-6 1 / K for YSZ). Many suitable insulating materials such as Al2O3 have a CTE lower than that of YSZ, whereas most of the material for brazing has a higher CTE. Therefore it is preferable to choose the thickness of the portion of the braze and insulating material such that the overall CTE of the composite insulating member (comprising braze and insulation material as shown in Figures 2 and 4) was close to the CTE of the components of the cell. For example, soldering of the insulating member of aluminum oxide of thickness 0.5 mm can be carried braze forming portion thickness of 0.2 mm.

When the insulating member comprises an adhesive, it is preferable to improve adhesion to the surface, the mating with adhesive were rough, porous, oxidised or coated with a primer. We investigated the effect of surface treatment on the shear strength lap joint obtained by joining strips of stainless steel 430 with an adhesive based on phosphate as the filler using insulating particles. The results are given in the table below. The table shows that all treatments increase shear strength. The surface of the electrode on the substrate of porous metal (e.g., electrode 2) is naturally similar to a sintered surface. Therefore, adhesion of the insulating adhesive with the electrode 2 should be strong. Increasing the strength of the connection node for the geometry shown in Figure 1, must be provided by treating the metallic casing assembly compound. Among suitable treatments include: chemical etching or oxidizing, sanding, sandblasting, scribing or knurling, etc..

Filling adgezivaPoverhnostnaya polosySoprotivlenie processing steel sections (kPa) Al2O3Ne provodilas1700Al2O3Pridanie roughness sand ochistkoy3000ZrO2He provodilas1400ZrO2Napekanie FeCR particles to obtain porous poverhnosti2900ZrO2Gruntovka adhesive silver napolneniem4300MgO / Al2O3Ne provodilas1000MgO / Al2O3Okislenie for 1 hour at 900 ° C for vozduhe1700

Figures 2 and 3 show additional illustrations of examples of the present invention described generally with reference to Figure 1, it includes many of the common features described above. 2, a first electrode (second electrochemical cell) is structurally and electrically connected to the metal casing assembly brazing compound 1, and a gas tight seal between electrodes 1 and 2 creates a pair of portions brazing (brazing portions 2 and 3) on both sides of the insulating member .

3, the first electrode and electrically and structurally connected to the metal casing assembly compound braze 1. However, in this embodiment, the braze portion is extended to provide contact with the electrolyte and also to create a gas tight seal between electrodes 1 and 2, regardless of the presence or lack of brazing portions 2 and 3 on both sides of the insulating member. In the absence of brazing portions, creating a seal between the insulating member and the electrolyte and between the insulating member and the metal casing, the insulating member may be displaced and CTE mismatch issues between the insulating member and the electrolyte does not occur.

SOFC on a metal substrate, comprising the connection node of the present invention may be assembled as follows:

Assembling the parts of the cell

1. Build unbaked (unbaked) of the blank electrode 2

- Forming the metal substrate

- The application of the porous intermediate layer the YSZ

2. Spray bars for the electrolyte to the electrode 2

3. Joint sintering electrode 2 and electrolyte in reducing atmosphere at a temperature of 1100-1400 ° C (typically 1300 ° C)

4. The application of green stock electrode electrolyte 1

- The application of the porous intermediate layer the YSZ

- Applying a current collector (a decorated metal)

5. Sintering of all the cell structure in a reducing atmosphere at a temperature of 1100-1400 ° C (typically 1300 ° C)

The structure of the cell is created (infiltration catalysts will be made later). Additional details of the assembly of the cell described herein, can be found in the transferred common use №6605316 U.S., incorporated herein by reference in their entirety and for all purposes.

Note: Step 3 is optional (i.e., all 5 layers can be subjected to co-sintered in one step). Step 3 allows you to carry out the inspection / quality control of the electrolyte layer prior to application of the electrode 1.

Assembling the parts of the connection node

6. A compound of the metal casing from the cell via the insulating element D

- Placement element

- If member D is an adhesive: cure (in air, various manufacturing operations in the temperature range 20-350 ° C)

- If member D is a dense spacer brazed reinforcement: curing step is unnecessary, and the connection will be accomplished later in step 8 brazing

7. Placing paste / powder / tablet brazing

Step 7 may also be formed during the assembly of Step 6

8. Braze in typically inert / reducing, possibly oxidizing atmosphere at a temperature 5-150 ° C above the melting point of the brazing material (i.e., at a temperature of 800-1100 ° C for the brazing materials based on silver)

9. Application of the protective coating (optional step, depending on nature of braze material, as noted above)

Brazing can be replaced by sintering of metal-metal electrode for connection of two metallic housing assembly (A) of the compound in the next cell segment into coherent structure; electrode 2 may be coupled to the insulating member (D) in the same cell using a decoration and sinter methods such as those described in co-pending international patent application PCT / US2005 / 043109, filed 29 November 2005 g.pod entitled "COMPOUND OF DISSIMILAR MATERIAL" ("JOINING OF DISSIMILAR MATERIALS"), claims priority to provisional US patent application №60 / 632,030, filed Nov. 30, 2004 under the name of "joining dissimilar materials" ("JOINING OF DISSIMILAR MATERIALS"), which are incorporated herein by reference. Stages 7 and 8 are replaced by another stage of sintering in a similar stage 5. Perhaps the inclusion of this step in the number of stages of the cell assembly.

The procedure required steps is optional, and can be adjusted for a particular set of inputs.

Preparation of catalyst

The catalysts may be infiltrated or incorporated into the cell during assembly of its parts.

The following description provides information regarding the preparation of catalysts in accordance with a specific embodiment: the catalysts (cathode / electrode 1 in particular) can not usually be processed under severe conditions required for brazing or metal sintering with the metal, so they are added after the completion of these stages.

10. Infiltration starting catalyst material into the porous YSZ and support / current collector

11. Formation of the catalyst (typically at 600-800 ° C in air)

- Formation of the catalyst may be a single step or may occur during the first cycle of operation of the cell.

Furthermore, details regarding the preparation of the catalyst described herein can be found in the transferred common use №6,682,842 U.S., incorporated herein by reference in their entirety and for all purposes.

Connection of the present invention may include without limitation, find use:

1) providing sealing / compounds in electrochemical devices;

2) ensuring the seal / connection in electronic devices;

3) providing sealing / connection devices transporting liquids and gases (e.g., heat exchangers, devices for separating gas, devices for desalination and gas Manifold).

Conclusion

Thus, the invention encompasses a combination of materials in a compact structure to provide all the necessary functions of the node connection for high-temperature electrochemical devices. It is also proposed a method of forming the node connections. Node Connection provides a seal, structural integrity, as well as electrical connection and isolation.

The foregoing has been a detailed description of the invention in order to ensure clarity of understanding, but it is obvious that it can be made certain changes and additions are possible without departing from the scope of the appended claims. It should be noted that there are many alternative ways of implementing both technologies and compositions of the present invention. Consequently, the implementation of the above examples should be considered as illustrative and not restrictive, and the invention should not be limited to the details herein.

All documents cited herein are incorporated by reference for all purposes.