Efficient operation of solid oxide fuel cell (SOFC) stacks requires uniform temperature and fuel utilization distributions in the stack. Especially high fuel utilizations necessitate uniform fuel flow dis-tributions to avoid performance decrease or anode reoxidation. A uniform temperature distribution helps to prolong the life-time of the stack. This work presents a method to determine the fuel utili-zation and temperature distribution in SOFC stacks with electro-chemical impedance spectroscopy (EIS). The equations for relat-ing the measured impedance and fuel utilization and temperature are derived from physical equations describing the SOFC stack. The method is demonstrated with an ElringKlinger AG 10-cell stack fuelled with 50%/50% H2/N2 at nominal operation condi-tions. The difference in temperature and fuel utilization between cells was determined. The calculated distributions are in line with cell voltage measurements. The method can be used to improve SOFC stack design and performance.
|Number of pages||10|
|Publication status||Published - 30 May 2017|
|MoE publication type||A1 Journal article-refereed|
|Event||15th International Symposium on Solid Oxide Fuel Cells, SOFC XV - Hollywood, United States|
Duration: 23 Jul 2017 → 28 Jul 2017