Solid oxide fuel cell device

A solid oxide fuel cell device comprising:

• a rectangular solid ceramic substrate extending in length from a first end surface to a second end surface, in width from a first side surface to a second side surface, and in height from a bottom surface to a top surface, wherein the first and second end surfaces, first and second side surfaces and bottom and top surfaces collectively define an exterior surface, and wherein thermal expansion occurs primarily along the length;
• an active structure internal to the exterior surface and extending along only a first portion of the length, the active structure comprising an anode in opposing relation to a cathode with an electrolyte therebetween, wherein the electrolyte is monolithic with the solid ceramic substrate, and wherein the first portion of the length along which the active structure extends is configured to be heated to an operating reaction temperature greater than 700° C. to generate a fuel cell reaction when the active structure is supplied with fuel and oxidizer;
• wherein a remaining portion of the length from the first portion is a non-active section of the solid ceramic substrate lacking the anode in opposing relation to the cathode and to which no heat is applied such that no fuel cell reaction can be generated and such that heat is dissipated along the remaining portion of the length away from the first portion,
• wherein a second portion of the length in the remaining portion of the length adjacent the first end surface and/or the second end surface is sufficiently distanced away from the first portion of the length such that the exterior surface in the second portion is at a low temperature below 300° C. when the first portion of the length is at the operating reaction temperature due to the heat from the first portion being dissipated along the remaining portion of the length;
• and
• wherein the anode and cathode each have an electrical pathway extending from the internal active structure to the exterior surface in the second portion of the length for electrical connection at the low temperature below the operating reaction temperature.