Fuel cells solid-state

The U.S. Department of Energy has a major program in the Solid State Energy Conversion Alliance to bring about dramatic reductions in fuel cell costs. The goal to cut costs to 400 per kilowatt by the year 2010 would make fuel cells competitive for most power applications. The objective is to develop a modular, all-solid-state fuel cell that can be mass-produced for different products in the same way as electronic components are made. 

This edition of the Fuel Cell Handbook is more comprehensive than previous versions in that it includes several changes. First, calculation examples for fuel cells are included for the wide variety of possible applications. This includes transportation and auxiliary power applications for the first time. In addition, the handbook includes a separate section on alkaline fuel cells. The intermediate temperature solid-state fuel cell section is being developed. In this edition, hybrids are also included as a separate section for the first time. Hybrids are some of the most efficient power plants ever conceived and are actually being demonstrated. Finally, an updated list of fuel cell URLs is included in the Appendix and an updated index assists the reader in locating specific information quickly. 

A flow diagram for a natural gas fueled, 4 MW class, solid state fuel cell power cycle is presented in Figure 9-11. A brief process description is given below, followed by a performance summary. Selected state point values are presented in Table 9-16. 

Figure 9-11 Schematic for a 4 MW Solid State Fuel Cell System... 

Table 9-16 Stream Properties for the Natural Gas Fueled Solid State Fuel Cell...

Ceria affords a number of important applications, such as catalysts in redox reactions (Kaspar et al., 1999, 2000 Trovarelli, 2002), electrode and electrolyte materials in fuel cells, optical films, polishing materials, and gas sensors. In order to improve the performance and/or stability of ceria materials, the doped materials, solid solutions and composites based on ceria are fabricated. For example, the ceria-zirconia solid solution is used in the three way catalyst, rare earth (such as Sm, Gd, or Y) doped ceria is used in solid state fuel cells, and ceria-noble metal or ceria-metal oxide composite catalysts are used for water-gas-shift (WGS) reaction and selective CO oxidation. 

Related systems It should be noted that specific properties for applications could be enhanced by using solid solutions, doped materials, and composites, instead of pure ceria. For example, ceria-zirconia solid solution is a well known ceria based material for enhanced OSC and high ionic conductivity for solid state fuel cell components. It is also used in the three way catalysts for automobile waste gas cleaning, because of the improved thermal stability, surface area, and reducibility. The synthesis, structure, and properties of ceria-zirconia have been actively studied for a long time. Di Monte and Kaspar et al. presented feature articles on the nanostructured ceria—zirconia-mixed oxides. The studies on phase, structures, as well as the microstructures are discussed and reviewed (Di Monte et al., 2004). 

Ke rwords Stabilized Zirconia/Solid State Fuel Cell/Thermal Stability/Combined Dopant/... 

During August 2001, the DOE announced a 500 million effort to produce breakthrough fuel cells that will overcome current cost barriers. DOE believes that developing an all-solid-state fuel cell "building block" that can be mass manufactured is one of the best ways to dramatically lower costs, much like advances in solid-state technology that have cut the costs of computers and other electronic devices. 

A Figure 1.20 Solid-State fuel cells manufactured by Bloom Energy. 

The six negative terms on the RHS of Eq. (2.30) are the usual definition of ASR. The comprehensive functionality of E and the more general definition of ASR have recently been developed for solid-state fuel cells with dense, mixed, ionic-electronic conducting electrolytes using the Wagner mass transfer model (MTM) [41,45,46] ... 

The comprehensive model for solid-state fuel cells incorporates not only the typical definition of ASR, but also electronic shorting, leakage, and other current loss mechanisms. The first term on the RHS of Eq. (2.32) is not an ASR term. 

A general ASR definition for solid-state fuel cells can be defined as follows ... 

The development of a modular, solid-state fuel cells that can be mass produced for different uses... 

However, a solid-state fuel cell device operated as high-speed response indicator for oxygen in gases has been announced to be commercially available suitable for monitoring the O2 content in flue gases... 

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