Durability Studies on PBI Based High Temperature PEMFC
Hans Aage Hjuler, Kobra Azizi, Nedjeljko Šešelj, Silvia M. Alfaro, Héctor R. García, Denys Gromadskyi, Larysa Hromadska, S. Primdahl, Jens Oluf Jensen, Qingfeng Li, Sanser Celenk, Lars Nilausen Cleemann
Abstract
HT-PEMFC based on phosphoric acid-doped polybenzimidazole membranes are a technology characterized by simplified construction and operation along with methanol reformers. Durability issues including acid loss, platinum sintering and carbon corrosion are recognized for both steady state and start-stop cycling operations. This work reports experimental studies on the degradation of PBI-based fuel cells operating with synthetic reformate fuel and air. Degradation stressors include elevated temperatures, pressures, current densities, and start-stop cycles. An average degradation rate of 9.3 mV/h is observed for continuous operation at 0.4 A/cm2 and 160 °C for 12,000 hours. High pressure (1.5 bara) operation at 170 °C and 0.8 A/cm2 shows an average degradation rate of 12.6V/h during a period of 2,000 hours. A start-stop test from 50 °C consisting of 240 cycles between temperatures of 165 and 175 °C and current density of 0.31 and 0.55 A/cm2 reveals a performance decay by 0.48-0.58 mV/cycle.