Research, Development, and Demonstration of Solid Oxide Fuel Cell Systems

The solid oxide fuel cell (SOFC) is an all-solid-state power system which operates at high temperatures to ensure adequate ionic and electronic conductivity of its components (T = 1000°C for the state-of-the-art system). The electrolyte is an oxide ion conductor. Since it is a solid-state system, it has advantages over other types of fuel cells.1 It is simpler in concept than both the molten carbonate fuel cell (MCFC) and the phosphoric acid fuel cell (PAFC), because these require the presence of three separate phases, compared with two in the SOFC. Two-phase (gas-solid) contact reduces corrosion and eliminates any problems of electrolyte management. Because of its high operating temperature, activation overpotentials are low during cell operation, and noble metal electrocatalysts are not necessary.2 However, this advantage is largely offset by the high fuel cell operating temperature, at which the free energy of formation is less negative than at room temperature, so that the open-circuit potential at practical gas utilizations is about 0.9 V. In spite of this, thermal efficiencies greater than 50% (corresponding to operation at 0.75 V, at least at modest current densities) can be obtained for chemical-to-electrical energy conversion in SOFCs.

[1]  C. Neugebauer.  Resistivity of cermet films containing oxides of silicon , 1970 .

[2]  H. Tuller,et al.  Alpha ‐ Ta2 O 5 An Intrinsic Fast Oxygen Ion Conductor , 1989 .

[3]  Carleton H. Seager,et al.  Electrical properties and conduction mechanisms of Ru‐based thick‐film (cermet) resistors , 1977 .

[4]  V. Stubican,et al.  Transport in Nonstoichiometric Compounds , 1985 .

[5]  F. R. Foulkes,et al.  Fuel Cell Handbook , 1989 .

[6]  F. H. Riddle.  AMERICAN CERAMIC SOCIETY , 1921 .

[7]  B. Baker.  Fuel Cell Systems-II , 1969 .

[8]  H. S. Spacil,et al.  Cathode Materials and Performance in High‐Temperature Zirconia Electrolyte Fuel Cells , 1969 .

[9]  A. Isenberg.  Energy conversion via solid oxide electrolyte electrochemical cells at high temperatures , 1981 .

[10]  Y. Ohno,et al.  Properties of oxides for high temperature solid electrolyte fuel cell , 1983 .

[11]  D. Dees,et al.  Conductivity of porous Ni/ZrO/sub 2/-Y/sub 2/O/sub 3/ cermets , 1987 .

[12]  R. Ruka,et al.  A Solid Electrolyte Fuel Cell , 1962 .

[13]  H. Tuller,et al.  Doped Ceria as a Solid Oxide Electrolyte , 1975 .

[14]  T. Kudo,et al.  Mixed Electrical Conduction in the Fluorite‐Type Ce1 − x Gd x O 2 − x / 2 , 1976 .

[15]  S. S. Penner,et al.  Assessment of Research Needs for Advanced Fuel Cells , 1985 .

[16]  N. Minh,et al.  Fabrication And Characterintion Of Monolithic Solid Oxide Fuel Cells , 1990, Proceedings of the 25th Intersociety Energy Conversion Engineering Conference.

[17]  K. A. Murugesamoorthi,et al.  Novel Approaches For Fabrication Of Thin Film Layers For Solid Oxide Electrolyte Fuel Cells , 1990, Proceedings of the 25th Intersociety Energy Conversion Engineering Conference.

[18]  H. Tuller,et al.  New tantala-based solid oxide electrolytes , 1981 .

[19]  H. Tuller.  6 – Mixed Conduction in Nonstoichiometric Oxides , 1981 .

[20]  N. J. Maskalick.  Design and Performance of Tubular Solid Oxide Fuel Cells , 1989 .

[21]  Takehiko Takahashi,et al.  Oxide ion conductors based on bismuthsesquioxide , 1978 .

[22]  A. T. Aldred,et al.  Localized level hopping transport in La(Sr)CrO/sub 3/ , 1979 .

[23]  H. E. Kissinger,et al.  Synthesis of air-sinterable lanthanum chromite powders , 1989 .

[24]  J. C. Olsen,et al.  THE AMERICAN INSTITUTE OF CHEMICAL ENGINEERS. , 1912, Science.

[25]  M. Sayer,et al.  Polaronic conduction in lanthanum strontium chromite , 1977 .

[26]  W. G. Parker.  Westinghouse Soled Oxide Fuel Cell Program - A 1990 Status Report , 1990, Proceedings of the 25th Intersociety Energy Conversion Engineering Conference.