Solid oxide fuel cells merits

Characteristic Features of Solid Oxide Fuel Cells 2.2.1 Merits and Demerits of SOFCs... 

Flowever, this condition provides some merits for solid oxide fuel cells. The most important one is that the operation temperature can be higher than the reforming temperature so that the heat required for the reforming process may be supplied from the SOFC exhaust heat, and this is one of the reasons why the efficiency of SOFCs can be high. For a similar reason, SOFCs are appropriate for hybrid systems with gas turbines in which further increase in efficiency can be expected by postcombustion of remaining fuels. 

Table 2.1 Merits and demerits of solid oxide fuel cells...

Some perovskite-type oxides show protonic conduction and are useful for hydrogen-related electrochemical devices, including application to solid oxide fuel cells (SOFCs). Iwahara et al. reported protonic conductivity of strontium-cerate-based perovskite-type oxides in 1981 [1], Since that time, various perovskite-type proton-conducting oxides have been found. For use of the proton-conducting perovskite oxides, we should understand not only their merits but also their weak points. This chapter concerns the protonconducting properties of typical cerium- and zirconium-containing perovskite oxides from the points of view of conductivity, stability, electrode affinity, and dopant effect. Mixed conduction occurring in a special composition of the perovskite oxide is also introduced. 

One area where there is considerable current interest in chromia-forming alloys is for metallic intercoimectors for solid oxide fuel cells (Quadakkers et al., 2003 Brady et al, 2006). For this application, a key figure of merit is the electrical conductivity of the external scale. This criterion excludes alumina and silica scales which are too insulating. Two examples are provided which show some of the potential alloy design strategies for this application. 

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