Abstract:
The invention of solid electrolyte fuel cell power generating system integrates heat exchange, combustion, exhaust recycle, steam/fuel conditioning, fuel reforming, water condensing, water drainage, or water recycle into monolithic honeycomb structures. Manifolds serve as honeycomb multiple channel group gas passageways between channels within a honeycomb or between honeycombs. The said manifolds also serve as electrical interconnect or electrical power leads between honeycomb channels within said honeycomb structure or between honeycomb fuel cell structures. Honeycomb fuel cells can be stacked by utilizing the said manifolds. The honeycomb fuel cell system converses chemical energy of a fuel gas into electrical energy by an electrochemical process. The said integrated honeycomb fuel cell system design demonstrates simple, robust, and integrated mechanical structure and may enhance power efficiency and low cost.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. provisional application No. 60/481,302 filed on Aug. 28, 2003 by Zhou with the title “Integrated Fuel Cell Power Generating System”. 
     
    
     BACKGROUND OF INVENTION  
       [0002]     Fuel cells are electrochemical devices that convert chemical energy of a reaction directly into electrical energy. Fuel cells can be divided into the following five categories based on electrolyte materials used: (1) solid oxide fuel cell (SOFC); (2) proton exchange membrane fuel cell (PEFMC); (3) molten carbonate fuel cell (MCFC); (4) phosphoric acid fuel cell (PAFC); and (5) alkaline fuel cell (AFC). Among these types of fuel cells, SOFC and PEMFC utilize solid electrolytes. In general, the solid electrolytes can be tubular, planar, or monolithic. I use solid electrolyte fuel cell to refer SOFC or PEMFC in the following text.  
         [0003]     For solid oxide fuel cells, tubular and planar types are commonly used. Tubular fuel cells are structurally robust. Planar fuel cells offer higher power density but less favorable in mechanical strength compared with tubular fuel cells. It is desirable to have a fuel cell design which may combine the advantages from both tubular and planar fuel cells. A monolithic honeycomb fuel cell structure may combine the advantages of high power density and structural robustness from planar fuel cells and tubular fuel cells, respectively.  
         [0004]     A typical solid oxide fuel cell generates electrical power by utilizing electrochemical reactions between fuel, such as, hydrogen or gaseous hydrocarbons, and oxidant, such as air. Its typical reactions are: (1) HC (Hydrocarbons)+H 2 O→CO+H 2 ; and (2) H 2 +O 2 →H 2 O. Reaction (1) is a hydrocarbon reforming reaction. Reaction (2) is a typical electrochemical oxidation reaction which results in power generation.  
         [0005]     Because of low mobility of charge carrier, O 2− , in solid oxide electrolyte, such as, Y 2 O 3  doped ZrO 2 , SOFC have to be operated at high temperatures, in a range of 600-1100° C. High temperature is required for both fuel reforming and electrochemical reactions. Feed gases including fuels and oxidants are required to be preheated before going through electrochemical reactions. Feed gases can be preheated by: (1) generating and exchanging heat from combustion of unconverted hydrocarbons contained in the exhaust gases; and (2) heat exchange between exhaust gases and feed gases. It is desirable to incorporate heat exchangers and combustors to provide efficient feed gas preheating. For honeycomb fuel cell structures, it is required to have multiple channels. In addition to oxidant and fuel channels, for example, more channels are needed for fuel reformation, exhaust gas recycle, and feed gas preheating.  
         [0006]     PEMFC can operate at a relatively low temperature, ˜80° C., because of high mobility of proton, H + , in polymer electrolytes. This enables the fuel cell to reach its operating temperature quickly. In addition to hydrogen, methanol can also be used in PEMFC as a fuel which is referred to as “direct methanol fuel cells” (DMFC). The key component for both PEMFC and DMFC is the material of proton electrolyte membranes. Presently, hydrated perfluorosulfonic acid based materials are used for PEMFC and DMFC. This type of materials has relatively high proton conductivity and excellent chemical, mechanical, thermal stability in the hydrated state. However, when temperature reaches above 80° C., proton conductivity reduces and methanol fuel crossover increases. Because of high cost of the membrane materials, composites containing hydrated perlouorosulfonic acid materials are made for the fuel cell applications with improved mechanical strength and lower costs. However, the membrane materials and the related composite materials are not mechanically stiff enough to be used alone without additional supporting structures which are usually made of precious metals. It is desirable to have reinforced composite proton exchange membrane capable of withstanding all the various load conditions experienced during fuel cell operations. Using such PEM as structural load carrier components of the PEMFC systems may largely reduce overall weight and cost of the PEMFCs. Furthermore, a honeycomb may be a good structure to meet the requirements of PEMFCs.  
         [0007]     The typical electrochemical reactions of PEMFCs are: (1) Anode: H 2 →2H + +2e − ; and (2) Cathode: 1/2O 2 +2H + +2e − →H 2 O. Then the overall electrochemical reaction is H 2 +1/2O 2 →H 2 O. This is an exothermic reaction. Rejected heat can not be utilized for cogeneration. Temperature increase may reduce electrolyte ohmic resistance and CO chemisorption which is an endothermic reaction. However, this is limited by high vapor pressure of water in the electrolytes which ion conductivity is susceptible to dehydration. In the PEMFCs, water is not produced as steam but as liquid. Water balance is very import. If water is surplus, electrodes will flood which prevent gas from being diffused to electrodes. If water is deficient, electrolytes will be dehydrated. Ionic conductivity decreases and cell performance degrades. It is desirable to have a built in heat and water management system for the PEMFCs. Honeycomb structure with plural channels may be suitable for the PEMFCs. In addition to oxidant and fuel channels, for example, extra channels are needed for water management, fuel reformation, or feed gas preheating for honeycomb structure fuel cells.  
         [0008]     A honeycomb structure fuel cell or honeycomb fuel cell stacks may provide improved mechanical integrity and lower costs for solid electrolyte fuel cells. The concept of using honeycomb structure for monolithic solid oxide fuel cells is well known. However, to integrate multiple functions, such as, fuel reforming, feed gas preheating, water management, exhaust gas recycle, honeycomb manifolds with multiple groups of channels is one of the key elements. The multiple channel groups may include but are not limited to the groups of fuel gas, oxidant gas, exhaust gas, and water steam. The above said manifolds may be applied to honeycomb solid electrolyte fuel cell stacks which include SOFC or PEMFC and honeycomb fuel reformers as well.  
       SUMMARY OF INVENTION  
       [0009]     In accordance with the invention, the said manifold designs and designs of fuel cell stacks based on the said manifolds are provided. It is an object of the present invention to utilize manifolds for providing plural gas passageways to honeycomb reformers or honeycomb solid electrolyte fuel cells including SOFC and PEMFC. The said manifolds maintain the gas passageways by connecting or grouping, in serial or parallel, the alternated channels of a honeycomb structure. These said honeycomb channels are formed by interconnecting walls which are parallel or non-intervened, extended from one face to the other of the said honeycomb. Each group of the channels can be assigned to but not limited to fuel gas, oxidant gas, exhaust gas, or water steam.  
         [0010]     It is an object of the present invention to utilize honeycomb manifolds for honeycomb fuel cell stakes or honeycomb fuel reformer stacks. Honeycomb manifolds interconnect multiple channel groups, usually more than two, gas passageways within a honeycomb structure, between honeycomb structures in a said stack, or with gas or water inlets or outlets. The said honeycomb manifolds provide gas passageway interconnections among the channels within a channel group of a honeycomb, in serial or parallel or both. The said manifolds provide channel interconnections between/among channel groups of a honeycomb, in serial or parallel or both. One of the examples of this feature is exhaust channel group that may interconnect fuel outlet channels and oxidant outlet channels. Such a channel group with mixed fuel and oxidant exhausts can be used for combustion in order to preheat feed gases or solid oxide fuel cell assembly itself. The said honeycomb manifold may also provide gas passageways between or among the same or different channel groups from different honeycombs in the stack, in serial or parallel or both.  
         [0011]     It is an object of the present invention to integrate a heat exchanger, a combustor, a fuel reformer, a water recycler, or any combinations including the above mentioned in the honeycomb fuel cells or honeycomb fuel cell stacks. The integration can be within single honeycomb fuel cells or a stack of multiple honeycomb fuel cells or a combination of both. In SOFCs, fuel and oxidant outlets may be grouped into exhaust channels and connected to combustor channels. The heat generated from the combustion can be used for preheating the system and the feed gases. After the system and feed gases are warmed up, fuel gas may pass through reformer for partial or complete conversion of hydrocarbons to hydrogen or smaller hydrocarbons or for surlpher depletion. Heat management for preheating feed gas or cooling the fuel cell system and water management for fuel conditioning are important in PEMFCs. These features may be integrated into the honeycomb PEMFCs or honeycomb PEMFC stacks.  
         [0012]     It is another object of the present invention to interconnects, via a manifold, electrodes between different channels either within a single honeycomb, between multiple honeycombs, or with electrical power leads, in series or parallel. Configurations of electrolyte, anode, cathode, and interconnect for a honeycomb fuel cell are also provided in this invention. Honeycomb manifolds may provide both gas passageways and electrical interconnections for honeycomb fuel cells.  
         [0013]     In carrying out the above objects of the present invention, a honeycomb fuel cell system is provided that integrates combustor, heat exchanger, reformer, fuel humidification, water drainage, exhaust recycle, water recycle, or in monolithic fuel cells via manifolds. The honeycomb fuel cell system of the present invention involves a fuel cell stack for conversion of chemical energy of a fuel gas into electrical energy by an electrochemical process.  
         [0014]     Other objects and advantages of the invention will become apparent upon reading the following detailed description and appended claims, and upon reference to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0015]      FIG. 1  is a schematic diagram of an embodiment of solid oxide fuel cell power generating system of the invention.  
         [0016]      FIG. 2 ( a ) to  FIG. 2 ( d ) Illustrate honeycomb structures with square cells and hexagonal cells.  
         [0017]      FIG. 3 ( a ) to  FIG. 3 ( d ) Illustrate equivalent circuits corresponding to honeycomb structures illustrated in  FIG. 2 ( a ) to  FIG. 2 ( d ), respectively.  
         [0018]      FIG. 4 ( a ) to  FIG. 4 ( k ) Illustrate honeycomb structure manifolds.  
         [0019]      FIG. 5  Illustrates a honeycomb manifold which provides electrical interconnect and stack support for segmented-cell-in-series.  
         [0020]      FIG. 6 ( a )- FIG. 6 ( b ) show electrical interconnection between two fuel cells via a manifold.  
         [0021]      FIG. 7 ( a )- FIG. 7 ( b ) show electrical interconnection between two fuel cells via a manifold. 
     
    
     DETAILED DESCRIPTION  
       [0022]     The honeycomb solid oxide fuel cell power generating system of the invention comprises:  
         [0023]     a) a honeycomb fuel cell structure containing electrolyte, an anode, a fuel inlet, a depleted fuel exhaust gas outlet, a fuel source in connection with a fuel inlet, a cathode, an oxidant inlet, an spent oxidant exhaust gas outlet, and an oxidant source in connection with oxidant inlet;  
         [0024]     b) a honeycomb structure integrated with a heat exchanger or a combustor via manifold with fuel cell;  
         [0025]     c) a means of recycling exhaust gas from depleted fuel exhaust gas outlet to heat exchanger in connection with fuel exhaust outlet and combustor in connection with heat exchanger; and  
         [0026]     d) a means of recycling exhaust gas from spent oxidant outlet to heat exchanger that is in connection with oxidant exhaust outlet.  
         [0027]      FIG. 1  shows a schematic diagram of integrated fuel cell power generating system of the invention. The system is preferably operated at temperatures between 600-1100°C. The air supply  1  is connected to heat exchanger  2  through the line  9 . The supplied air is preheated by high temperature exhaust gas through heat exchanger  2  and combustor  4  which utilizes unspent fuel from fuel cell  5  through connection  16 . The preheated air is supplied to fuel cell  5 , through connection  10 . Meanwhile, fuel supply  3  is connected to heat exchanger  7  through line  18 . Fuel is preheated in heat exchanger  7  and is further preheated by combustor  4  which burns unspent fuel exhaust from the fuel cell  5 . The preheated fuel is then provided to fuel cell  5  in which hydrocarbon fuel will be reformed and/or directly oxidized as follows: 
 HC+O 2 →H 2 +CO 2    H 2 +O 2 →H 2 O  and/or  HC+O 2 →H 2 O+CO 2    
         [0028]     The hydrocarbon can be methane, propane, etc. The unspent fuel exhaust from fuel cell  5  and feed to combustor  4  where the unspent fuel will be combusted exothermically. The heat generated from the combustion is transferred to heat exchanger  2  and  6  for preheating feed gases to support fuel cell endothermic reforming reaction.  
         [0029]     The exhaust from combustor  4  goes through heat exchanger  2  and  6  for preheating and then is released to environment through exhaust lines  8  and  13  as shown in  FIG. 1 .  
         [0030]      FIG. 2 ( a )- FIG. 2 ( d ) show honeycomb structures for fuel cell applications. The honeycomb cells may include square, hexagonal, and other polygonal shapes. In  FIG. 2 ( a ), shaded cells  19  aligned along the dotted line A. Open cells  20  aligned along the dotted line B. The shaded cells along the line A and the open cells along the line B alternate in a format of ABAB. For example, the shaded cells  19  may be considered as fuel channels and the open cells  20  may be considered as air channels. Each wall between fuel and air channels form an electrolyte cell that generates electromotive force. The honeycomb structure that forms these channels and walls comprise a group of fuel cells. These fuel cells may be connected each other in parallel or series.  
         [0031]      FIG. 2 ( b ) shows honeycomb square cells. The shaded cells  21  and open cells  22  alternate along the dotted line A′. Open cells along the dotted line B alternate with mixed cells along the dotted line A′ in a format of A′BA′B.  
         [0032]      FIG. 2 ( c ) shows an example of a combination of channels for fuel, air, fuel preheating, air preheating, fuel exhaust, and air exhaust. Cells  21   a  may be considered, for instance, fuel channels, cells  22   a  may be considered air channels, cells  21   b  preheated air channels, cells  22   b  preheated fuel channels, cells  21   c  depleted fuel exhaust channels, and cells  22   c  spent air exhaust channels. The gas preheating channels and exhaust gas channels,  21   b ,  22   b ,  21   c ,  22   c , are intervened with fuel and air channels  21   a  and  22   a  for heat exchange.  
         [0033]      FIG. 2 ( d ) shows honeycomb hexagonal cells. The shaded cells  23  are separated by open cells  24 . The walls between these channels form fuel cells. The hexagonal honeycomb structure forms a group of such fuel cells. Other polygonal cells may also be constructed in the same fashion, such as, triangular cells.  
         [0034]     Presumably, honeycomb substrate material is electrically insulating.  FIG. 3 ( a )- FIG. 3 ( d ) show equivalent circuits for corresponding honeycomb structures as shown in  FIG. 2 ( a )- FIG. 2 ( d ), respectively.  
         [0035]      FIG. 4 ( a )- FIG. 4 ( b ) show honeycomb fuel cell manifold structures.  FIG. 4 ( a ) shows a simple honeycomb manifold which allows one gas flow through the openings  27  and allows another gas flow through the side openings  26 .  FIG. 4 ( b ) shows a manifold which forms three independent gas entrances. One gas flows through the opening  35 . Another gas flows through the side openings  34  and  36 . A third gas flows through the side openings  33  and  37 . More complicated manifold can be formed in a similar fashion for multiple gas passageways. These openings can be gas outlets or inlets or any combinations of gas outlets and inlets. This allows preheating fuel, preheating air, supplying fuel, supplying air, depleted fuel recycle, and spent air to exhaust in their own channels without being mixed.  FIG. 4 ( c ) illustrates another fashion of manifold for  3  gas passageways in a square honeycomb. One gas passageway is through the honeycomb channels as shown as flow  1  per  FIG. 4 ( b ). The second gas passageway is through the perpendicular channels to the honeycomb channels as shown as flow  2  in  FIG. 4 ( c ). The third gas passageway is perpendicular to both flow  1  and flow  2  and as shown in  FIG. 4 ( c ). As seen in Fib.  4 ( c ), the perpendicular channels may be provided by the through holes. The honeycomb channels which connect to those perpendicular channels are blocked at ends. This converges honeycomb channels to three groups of channels. Each group of channels have their own directions which may separate the gas openings apart and make gas passageway interconnections easy.  FIG. 4 (D)-(F) describe another manifold.  FIG. 4 (D) is a front view of the manifold for honeycombs with square channels. The manifold has one to one corresponding channels to interconnect with the honeycomb channels. Some of the channels labeled “flow  1 ” as shown in  FIG. 4 (D) may directly lead the honeycomb channels to the manifold openings. Some of the honeycomb channels as predetermined may be combined by channels perpendicular to the honeycomb channel direction. The perpendicular channels lead to the openings denoted as “flow  2 ” as shown in  FIG. 4 (D). Some of the channels are combined by diagonal channels which are perpendicular to the honeycomb channels and in angle of 45 degrees with the perpendicular channels. The diagonal manifold channels lead to the side openings denoted as “flow  3 ” as shown in  FIG. 4 (D). These channels are perpendicular to the honeycomb channels but with  135  angles with flow  2  channels. The manifold channels may not be limited by any shapes. The round channels shown in the drawings are for illustrative and simplicity purpose. Manifold channels may not be limited by three as shown in the drawings. Higher channel count manifolds are possible. Again, for simplicity and illustrative purpose, I use three or less groups of manifold channels for descriptions and explanations.  FIG. 4  (E) shows the manifold side view. All of the honeycomb channels have one-to-one interconnection with manifold channels. However, these manifold channels have three levels of depths. The first depth is through holes which form “flow  1 ” channels as shown in  FIG. 4 (D-E). The second level of manifold channel depth exits to the side openings “flow  2 ” via perpendicular channels as shown in  FIG. 4 (D-E). The third level of manifold channel depth exits to the side openings “flow  3 ” via perpendicular channels as show in  FIG. 4 (D-E). The  FIG. 4 (F) shows the 3-D manifold which further describes the channel interconnections between manifold and honeycomb and manifold internal channel structures as well. For SOFC applications, the manifold may be made of ceramics, e.g. Al 2 O 3  or cordierite. In other applications, high purity Al 2 O 3  is used as high temperature molten metal filtering and cordierite is used in automotive catalytic converters. For honeycomb fuel cells, manifold may also provide electrical interconnections between electrodes. This requires that a manifold shall be made as a substrate for continuous electrical leads without short circuit. One may use wash coating to deposit electrical conductor layers utilizing selective grouped manifold channels.  FIG. 4 (G)-(H) demonstrate a manifold for hexagonal honeycomb fuel cells. The manifold channel group  1  is perpendicular to the paper and denoted as “ 1 ” for each of its openings as seen in  FIG. 4 (G). These channels are straight with and connected to the honeycomb structure channels. The manifold channel group  2  is perpendicular to the honeycomb fuel cell channels and have openings across the manifold from the top to the bottom which are denoted as “flow  2 ” as seen in  FIG. 4 (G). The manifold channel group  3  is perpendicular to both of the channel group  1  and  2 . It has the similar configurations to the channel group  2 . As seen in  FIG. 4 (H), the manifold may be made of individual slabs. For each slab, selective through holes and grooves may made to interconnect the predetermined channels. A manifold may be provided using combinations of these slabs with different patterns of through holes and grooves for various channel shapes and gas passageways of honeycomb fuel cells. These slabs may be combined by seals. These slabs and manifold can be further extended for multiple honeycombs for gas passageways and electrical interconnections.  FIG. 4 (I)-(J) shows similar manifold configurations for triangle honeycomb channels.  FIG. 4 (K) illustrates interconnections among multiple honeycombs. The structure may be dependant upon the manifold configurations and design requirements for gas and electrical interconnection. Electrically conductive seals may be a good choice for adhesion between a manifold and honeycomb, gas leak proof, and electrical interconnections.  
         [0036]      FIG. 5  shows a manifold which allows two gases from honeycomb  39  to enter into honeycomb  38  via manifold  40  without being mixed. Presumably, the manifold  40  is electrically conductive either in bulk or by surface coated electrical layers. The manifold serves an electrical interconnect between the honeycomb  38  and  39  in addition to maintaining gas passageways.  
         [0037]      FIG. 6 ( a ) illustrates an electrical interconnection configuration via manifold. Honeycomb  49  and honeycomb  58  are mechanically jointed by a manifold  56 . Air and fuel gas flow through the aligned channels in  49  and  58 . Part  50  is a porous support for an anode layer  51 , an electrolyte layer  52 , and a cathode layer  53  in honeycomb structure  49 . Part  63  is a porous support for an anode layer  62 , an electrolyte layer  61 , and a cathode  60  in honeycomb structure  58 . Part  57  is an electrical interconnection slab of manifold  56 . The manifold  56  can be metallic or surface coated or partially coated with an electrical conducting layer. It is noticed that a cathode layer  53  is connected with an anode layer  62  via manifold slab  57 . It is also noticed that the cathode  53  and  62  can be directly interconnected with seals  54  and  59  without the manifold slab  57 . In this case, the manifold  56  without the slab  57  serves as mechanical support and alignment for the honeycombs  49  and  58 . The electrical interconnection is sealed with an electrical conductive seal  54  and  59 . Seal  55  is to seal manifold  56  and honeycomb structures  49  and  58 . The porous support  50  for anode can be embedded with catalysts for hydrocarbon reform.  
         [0038]      FIG. 6 ( b ) illustrates an electrical interconnection configuration via manifold. Honeycomb  64  and honeycomb  72  are mechanically jointed by a manifold  70 . Air and fuel gas flow through the aligned channels in  64  and  72 . Part  65  is a porous anode which supports an electrolyte layer  66  and a cathode layer  67  in honeycomb structure  64 . Part  74  is a porous cathode which supports an electrolyte layer  75  and an anode layer  76  in the honeycomb structure  72 . Part  71  is an electrical interconnection slab of manifold  70 . The manifold  70  can be metallic or surface coated or partially coated with an electrical conducting layer. It is noticed that an anode support  65  is connected with an cathode support  74  via manifold slab  71 . It is also noticed that the anode  65  and cathode  74  can be directly interconnected with seal  68  and  73  but without the manifold slab  71 . In this case, the manifold  70  without the slab  71  serves as mechanical support and alignment for the honeycombs  64  and  72 . The electrical interconnection is provided with an electrical conductive seal  68  and  73 . Seal  69  is to seal manifold  70  and honeycomb structures  64  and  72 . The porous anode  65  can be used for direct hydrocarbon oxidation.  
         [0039]      FIG. 7 ( a ) illustrates an electrical interconnection configuration via manifold. Honeycomb  77  and honeycomb  84  are mechanically jointed by a manifold  96 . Air and fuel gas flow through the aligned channels in  77  and  84 . Part  78  is a porous anode which also supports an electrolyte layer  79  and a cathode layer  80  in the honeycomb structure  77 . Part  89  is a porous support for an anode layer  88 , an electrolyte layer  87 , and a cathode layer  86  in the honeycomb structure  84 . Part  83  is an electrical interconnection slab of manifold  82 . The manifold  82  can be metallic or surface coated or partially coated with an electrical conducting layer. It is noticed that an anode support  78  is connected with an cathode layer  86  via manifold slab  83 . It is also noticed that the anode  78  and cathode  86  can be directly interconnected with seal  85  without the manifold slab  83 . In this case, the manifold  82  without the slab  83  serves as mechanical support and alignment for the honeycomb structures  77  and  84 . The electrical interconnection is secured with an electrical conductive seal  85 . Seal  81  is to seal manifold  82  and honeycomb structures  77  and  84 . The porous anode  78  can be used for direct hydrocarbon oxidation. The porous support  89  for anode can be embedded with catalysts for hydrocarbon reform.  
         [0040]      FIG. 7 ( b ) illustrates an electrical interconnection configuration via manifold. Honeycomb  90  and honeycomb  97  are mechanically jointed by a manifold  95 . Air and fuel gas flow through the aligned channels in both  95  and  97 . Part  93  is a porous cathode which supports an anode layer  92  and a cathode layer  91  in honeycomb structure  90 . Part  102  is a porous support for an anode layer  101 , an electrolyte layer  100 , and a cathode layer  99  in the honeycomb structure  97 . Part  96  is an electrical interconnection slab of manifold  95 . The manifold  95  can be metallic or surface coated or partially coated with an electrical conducting layer. It is noticed that an cathode support  93  is connected with an anode layer  101  via manifold slab  96 . It is also noticed that the cathode  93  and anode  101  can be directly interconnected with seal  98  without the electrical interconnecting slab  96 . In this case, the manifold  95  without the slab  96  serves as mechanical support and alignment for the honeycomb structures  90  and  97 . The electrical interconnection is secured with an electrical conductive seal  98 . Seal  94  is to seal manifold  95  and honeycombs  90  and  97 . The porous support  102  for anode can be embedded with catalysts for hydrocarbon reform.