Long‐Term Testing in Dynamic Mode of HT‐PEMFC H3PO4/PBI Celtec‐P Based Membrane Electrode Assemblies for Micro‐CHP Applications

摘要: High temperature proton exchange membrane fuel cells (HT-PEMFC) have a promising market in micro-combined heat and power (μ-CHP) applications. Operating above 150 °C, they would better cope with return temperatures of typical heating systems than conventional PEMFCs allow simplification system regulations dedicated to failure prevention. Single cell 500 We HT-PEMFC stack integrating Celtec P 1000 MEAs were fed synthetic reformate air successfully operated at 160 °C under accelerated annual μ-CHP profile. The single was unaffected by 500 h current cycling while stop/start cycles induced some voltage loss. After 658 h cumulated operation, performance loss limited 7.6%: its electrical efficiency (LHV) decreased from 30.6 28.3%. Moreover, four initial weakly impacted performance, indicating that selected shutdown/restart protocol is convenient for field application. Conversely, after additional start/stop cycles, degradation rate increased specific (mostly associated lower OCV) exhibited significantly higher rates. Finally, transient evolution during step exhibits undershoot which magnitude strongly depends on location the stack: it dead-end exhibiting highest