SOFC applications

FIGURE 4.5 Schematic of alloy design for SOFC applications. 

Comparison of Key Properties of Different Alloy Groups for SOFC Applications... 

Hui R, Wang Z, Kesler O, Rose L, Jankovic J, Yick S et al. Thermal plasma spraying of SOFCs applications, potential advantages, and challenges. J. Power Sources 2007 170 308-323. 

Summarizing progress in the field thus far, the book describes current materials, future advances in materials, and significant technical problems that remain unresolved. The first three chapters explore materials for the electrochemical cell electrolytes, anodes, and cathodes. The next two chapters discuss interconnects and sealants, which are two supporting components of the fuel cell stack. The final chapter addresses the various issues involved in materials processing for SOFC applications, such as the microstructure of the component layers and the processing methods used to fabricate the microstructure. 

The final chapter addresses the cross-cutting issue of materials processing for SOFC applications. The challenges in developing materials that satisfy the stringent materials property requirements is further complicated by the need to fabricate the materials in the desired shapes and with the desired microstructures. The production of a cost-effective SOFC requires compromises between materials properties and processing methods to produce materials with adequate properties at an acceptable cost. 

At the temperatures of interest for SOFC applications, the standard potentials for oxidation, Go, are similar for hydrocarbon fuels and for H2 and CO, as shown in Table 1. Since Eo for H2 is more temperature dependent than the Eg for hydrocarbons, the thermodynamic advantage for hydrocarbon fuels is more apparent at higher temperatures. However, the... 

Wang, L.S. et ah, Sputter deposition of yttria-stabilized zirconia and silver cermet electrodes for SOFC applications, Solid State Ionics, 52, 261-267 (1992). 

Evaporation and condensation of chromium vapor from the interconnect onto the air electrode are considered critical mechanisms of performance degradation in an SOFC. While no details of similar effect have been reported for the electrolysis stacks, such a mechanism is likely to be operative, leading to performance degradation. This is another area that requires attention to address and mitigate the problem in order to achieve long-term stable operation of SOFC stacks. Much of the work in this area is being conducted for SOFC applications. 

Milliken, C., Elangovan, S., and Khandkar, A., Mechanical and electrical stability of doped LaCr03 in SOFC applications, in Proceedings of the Third International Symposium on Solid Oxide Fuel Cells, S.C. Singhal and H.I. Iwahara, ed., 335, Pennington, NJ The Electrochemical Society, 1993. 

FIGURE 11.2 Schematic of alloy options for SOFC applications. 

L.-W. Tai, M.M. Nasrallah and H.U. Anderson, Lai-xSrxCoi-yFeyOs-a, A potential cathode for intermediate temperature SOFC applications, in S.C. Singhal and H. Iwahara (Eds.), Proceedings of the 3rd International Symposium on Solid Oxide Fuel Cells. The Electrochemical Society, Pennington, NJ, 1994, pp. 241-251. 

High temperature fuel cells (MCFC and SOFC) allow for the reforming process to take place inside the fuel cell stack which lowers the requirement for cell cooling and reduces cost due to absence of the external reformer vessel. A future SOFC application could also be the production of hydrogen (and electricity) by internal reforming of natural gas where more H2 as a component of the synthesis gas is produced than can be converted electrochemically into electricity the heat losses from the fuel cell operation would be used as the endothermal heat source for the reforming step [65]. 

DEVELOPMENT OF NANO-STRUCTURED YSZ ELECTROLYTE LAYERS FOR SOFC APPLICATIONS VIA SOL-GEL ROUTE... 

In order to realize the sol-gel method as a competitive technique in manufacturing of electrolyte layers for SOFC applications, further optimizations of fabrication procedures are required in the future work. For example, surface treatment of the substrates and proper thermal treatment of all layers are proposed to avoid delamination of the cathode. Deposition of a Ceo 8Gdo.20i 90 barrier layer will protect the electrolyte from the diffusion of Strontium and efficiently avoid formation of isolating zirconate layers. 

Dense electrolytes with a thickness of 3 pm have been deposited on warm-pressed anode substrates by a graded multi-layer sol-gel coating method. By applying a LSCF cathode, current density of about 840 mA/cm and power density of 588 mW/cm has been realized. It could be demonstrated that it is possible to produce highly dense YSZ electrolyte for SOFC application via sol-gel route. Enhanced electrochemical performances of single cells are expected in the future work through optimizations of fabrication procedures. 

AN OVERVIEW OF SCANDIA STABILIZED ZIRCONIA ELECTROLYTE DEVELOPMENT FOR SOFC APPLICATION... 

Scandia Stabilized Zirconia (ScSZ) shows good potential for SOFC application because of its high electrical conductivity. But, the fundamental study such as suitable composition, mechanical properties and chemical stability are insufficient to compare with Yttria Stabilized Zirconia (YSZ) which is promising material for SOFC application. 

Therefore, we have studied the properties of ScSZ for SOFC application. This paper briefly overview our ScSZ development. 

Overview of Scandia Stabilized Zirconia Electrolyte Development for SOFC Application... 

PERFORMANCE OF ELECTROLYTE SUPPORTED CELL Above results, lOSclCeSZ is expected to be the good material for SOFC application. The electrolyte supported Cell (ESC) using lOSclCeSZ for intermediate temperature SOFC was developed in this study. We have studied various electrode materials to match the lOSclCeSZ electrolyte and find that the specifications in Table 1 show good cell performance. 

Viable, especially in SOFC applications (flue gas N2 lean)... 

MICROSTRUCTURAL CHARACTERIZATION OF La-Cr-O THIN FILM DEPOSITED BY RF MAGNETRON SPUTTERING ON THE STAINLESS STEEL INTERCONNECT MATERIALS FOR SOFC APPLICATION... 

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