NOVELTY - The fuel cell device (10) comprises a ceramic support structure having a length in an x direction from a first end (11a) to a second end, a width in a y direction from first side to a second side and a thickness in z-direction from a top surface to a bottom surface, a reaction zone positioned along a first portion of the length spaced apart from the first end and having an active layer within the ceramic support structure, and a first artery flow passage and a second artery flow passage extending from the first and second side end portions of the first and second ends in the x-direction.    USE - The fuel cell device is useful in a fuel cell system (claimed).    ADVANTAGE - The fuel cell device has high power output (1-10 KW output) and density, reduces the heat transfer out along the ceramic plates thus providing good flow rates, when increases its overall size, and can be economically and efficiently manufactured with good temperature cycle performance, high scalability and productivity and reduced amount of expensive precious metals and without sacrificing density.    DETAILED DESCRIPTION - The fuel cell device (10) comprises a ceramic support structure having a length in an x direction from a first end (11a) to a second end, a width in a y direction from first side to a second side and a thickness in z-direction from a top surface to a bottom surface, a reaction zone positioned along a first portion of the length spaced apart from the first end and having an active layer within the ceramic support structure, and a first artery flow passage and a second artery flow passage extending from the first and second side end portions of the first and second ends in the x-direction along the length adjacent to the first side and to the second side and into the reaction zone and having a thickness in the z direction respectively. The length is greater than the width or thickness. The x-direction of the ceramic support structure is a dominant direction of thermal expansion. The ceramic support structure comprises an electrolyte separating a first electrode from an opposing second electrode, an active first gas passage adjacent to the first electrode, and an active second gas passage adjacent to the second electrode. Each of the active first and second gas passages has a thickness in the z direction. The active first gas passage comprises first sub-passages extending in the y direction and spaced apart in the x direction. The active second gas passage comprises second sub-passages spaced apart in the x direction and extending in the y direction toward the first side. The first and second artery flow passage are fluidically coupled to each of the first and second sub-passages of the active first and second gas passages respectively, and have a thickness greater than the thickness of each of the first and second sub-passages of the active first and second gas passages respectively. The first and second sub-passages extend from the first and second artery flow passages in the y direction toward the first and/or second sides respectively. Each of the first sub-passages decreases in area and/or volume between the first artery flow passage and the second side. Each of the second sub-passages decreases in area and/or volume between the second artery flow passage and the first side. The decrease in area and/or volume for each of the first and second sub-passages is a continuous decrease and a stepped decrease. The first end and the second end each include a groove extending in the x direction between the first side and the second side by splitting each of the first and second ends into a first side end portion and a second side end portion. The first sub-passages and second sub-passages are fluidically coupled to a first artery exhaust passage and a second artery exhaust passage extending along the length adjacent to the second side and to the first side from the reaction zone to the second side end portion and first side end portion of the second and first ends respectively. The fuel cell device further comprises first vertical flow channels and second vertical flow channels extending in the z direction from each of the first sub-passages and second sub-passages toward the top and/or bottom surface adjacent to but not intersecting the second artery flow passage and first artery flow passage on the second side and first side respectively, a first exit flow channel and a second exit flow channel on or adjacent to the top and/or bottom surface fluidically coupled to each of the first vertical flow channels and second vertical flow channels and extending in the x direction toward the second end to a desired first exit point and the first end to a desired second exit point respectively, a cold zone along a second portion of the length configured to be shielded from the heat source to remain at a low temperature below the operating reaction temperature, when the reaction zone is heated, a fuel passage within the ceramic support structure extending from the cold zone to the reaction zone and having an associated anode in the reaction zone within the ceramic support structure, an oxidizer passage within the ceramic support structure extending from the cold zone to the reaction zone and having an associated cathode in the reaction zone positioned in opposing relation to the anode within the ceramic support structure, an electrolyte disposed between the opposing anode and cathode in the reaction zone, a current collector extending continuously over the segmented electrode, and a ceramic support member connecting the first and second end members in the cold zone. The reaction zone is configured to be exposed to a heat source to heat the reaction zone to an operating reaction temperature. The anode and/or cathode or both is a segmented electrode having an area and a thickness and includes electrode material segments in a spaced pattern in the area and separated by gaps extending to the thickness of the segmented electrode. The current collector is positioned over the gaps to form voids between the electrode material segments, and fills the gaps between the electrode material segments. The anode is the segmented electrode having a different physical and/or material properties and a different composition than the current collector. The cathode is non-segmented and thicker than the anode. The current collector comprises a different metal element than the segmented electrode. An INDEPENDENT CLAIM is included for a fuel cell system.    DESCRIPTION OF DRAWING(S) - The diagram shows a perspective view a first end of a fuel Cell device.    Fuel cell device (10)    First end (11a)    Fuel inlet (12)    Ceramic (29)    Supply tube (50)    Tie wrap. (52)