Degradation analysis of an H2/O2 proton exchange membrane fuel cell with dead-end cathode and anode under long-term operation

Fuel cell technology offers high-efficiency, low-emission electricity generation and has gained increasing attention for its potential in sustainable energy systems. Dead-end operations have been implemented to improve system performance by enhancing the fuel utilization. However, during dead-end operation, effective water management and attention to degradation-which can accelerate over time-are crucial. In this study, the anode and cathode of a hydrogen-oxygen proton exchange membrane fuel cell are operated in dead-end mode with various levels of gas supply humidification. The purge strategy for dead-end operation is based on the current integral for both the anode and cathode, and its effect on gas utilization and catalyst layer degradation is investigated. The results indicate that the optimal cathode purge strategy is 1400 As, which results in the highest oxygen utilization and helps prevent voltage fluctuations. On the anode side, operating at 5000 As is more suitable for achieving stable voltage output and reducing degradation. To optimize reactions and prevent water flooding, the humidity level should be maintained at around 50 % relative humidity for both the anode and cathode. This is crucial to reduce catalyst degradation, which can occur with approximately a 30 % decay at the anode outlet, while still maintaining satisfactory performance.