MEA durability is influenced by operating conditions, impurities, and mechanical stress.
Common fuel cell MEA stressors
* Start/stop cycling (carbon corrosion)
* Dry-out and re-wetting cycles (membrane stress)
* Contaminants (CO, sulfur compounds, silicones, ammonia)
* Local oxygen starvation / hotspots
Common electrolyser MEA stressors
* High anode potentials (material corrosion)
* Catalyst dissolution (oxygen side catalysts are often the limiting factor)
* Water purity issues
* Bubble management (gas blocking active sites)
Signs of MEA issues (general)
* Falling voltage at a given load
* Higher internal resistance
* Reduced maximum power
* Increased sensitivity to humidity/temperature
* Cell-to-cell imbalance within a stack