Experimental investigation of fuel starvation on industrial-sized solid oxide fuel cells using segmented cathodes and area specific resistances

Fuel starvation must be detected timely to avoid anode oxidation, especially for industrial-sized Solid oxide fuel cells (SOFCs). In this work, a practical segmented cell measurement method is developed to detect fuel starvation occurring in local regions. For this developed method, the cathode of SOFCs is segmented, and only the voltage signal is measured in the segments. The local current-voltage (I-V) curve per segment is determined using the local voltage and the global I-V curve. Then, area specific resistance (ASR) is calculated and compared among segments to validate the data reliability. Varieties of current density loading rates and fuel flow rates are correspondingly investigated. Furthermore, fuel starvation is estimated using the rapid voltage drop in I-V curves and the rapid ASR increment in I-ASR curves. The results show that the intrinsic ASR increment is a more sensitive and robust criterion to identify the occurrence of fuel starvation than the voltage drop. This work will considerably benefit the progress of fuel starvation avoidance by setting a constant ASR threshold.

Automated summary

A practical segmented cell measurement method is developed to detect fuel starvation in solid oxide fuel cells (SOFCs) at local regions. By segmenting the cathode and only measuring the voltage signal, the local current-voltage (I-V) curve per segment is determined. The area specific resistance (ASR) is calculated and compared among segments to validate the data reliability. Fuel starvation is estimated using the rapid voltage drop in I-V curves and the rapid ASR increment in I-ASR curves, with the ASR increment being a more sensitive criterion.