A Parametric Study of SOFC Performances with Multi-Stage Electrochemical Oxidation for Enhancement of Electric Efficiency

The solid-state ceramic construction of SOFCs enables high fuel to electricity conversion efficiencies as high as 50 to 60 percent LHV with high temperature operation, allows more flexibility in fuel choice.  Preceding studies have been  reported on multi-stage electrochemical oxidation with SOFCs for further improvement of the electric efficiencies. However there are many parameters for the multi-stage oxidation, and effects of the parameters on the efficiency remains to be identified.

In this study, we have conducted a parametric study of SOFC performances with multi-stage electrochemical oxidation by using a symbolic analysis method developed for the parametric analysis to investigate the possibility of enhancement of the electric efficiencies. In the case of two-stage oxidation, the parameters having important impacts on the efficiency are found to be ratio of active electrode area of a first stack to a second stack, and net fuel utilization which should be decided by the ratio and the fuel utilization limit of the each stack.

This research is supported by The Japan Science and Technology Agency (JST) through its COI Program.