Direct electrochemical conversion of carbon to electrical energy in a high temperature fuel cell

Abstract

A high temperature fuel cell (10) having first and second temperature zones (14, 16) for directly converting carbon fuel (12) to electrical energy comprises a first heat source (22), a second heat source (26), and a housing (18) that includes a non-porous section (15) and a solid electrolyte (30) having first and second electrolyte surfaces (32, 34) to which first and second electrodes (36, 38) are electrically connected. The first heat source (26) establishes first temperature zone (14) in the vicinity of the solid electrolyte (30) for adjusting the conductivity of the solid electrolyte (30) and electrodes (36, 38). The second heat source (26) is positioned in the vicinity of non-porous section (15) of housing (18) a distance from first heat source (22) to establish second temperature zone (16). A fuel compartment (20) defined by the first electrolyte surface (32) of solid electrolyte (30) and the non-porous section (15) of housing (18) spans first and second temperature zones (14, 16) to allow intermixing of oxygen provided through solid electrolyte (30) and a carbon fuel (12) which is located primarily in second temperature zone (16). The fuel compartment (20) may be provided with a gas inlet (25), gas outlet (27), and return line (31) through which non-reactive gas can be circulated to enhance the mixing of oxygen with carbon fuel (12). To generate electrical power, second temperature zone (16) is adjusted to a temperature which favors the complete oxidation of carbon fuel (12), first temperature zone (14) is adjusted to a temperature that minimizes the resistance of solid electrolyte (30) and electrodes (36, 38), and oxygen is provided by supplying an oxygen containing gas to the second electrolyte surface (32) of solid electrolyte (30).

Dependencies are inferred from the claim text.