Journal of Power Sources, Vol.328, 75-80, 2016
Fast stack activation procedure and effective long-term storage for high-performance polymer electrolyte membrane fuel cell
Time-saving stack activation and effective long-term storage are one of most important issues that must be resolved for the commercialization of polymer electrolyte membrane fuel cell (PEMFC). Herein, we developed the cost-effective stack activation method to finish the whole activation within 30 min and the long-term storage method by using humidified N-2 without any significant decrease in cell's performance for 30 days. Specifically, the pre-activation step with the direct injection of DI water into the stack and storage at 65 or 80 degrees C for 2 h increases the distinctive phase separation between the hydrophobic and hydrophilic regions in Nafion membrane, which significantly reduces the total activation time within 30 min. Additionally, the long-term storage with humidified N-2 has no effect on the Pt oxidation and drying of Nafion membrane for 30 days due to its exergonic reaction in the cell. As a result, the high water content in Nafion membrane and the decrease of Pt oxidation are the critical factors that have a strong influence on the activation and long-term storage for high-performance PEMFC. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Polymer electrolyte membrane fuel cell (PEMFC);Stack activation;Long-term storage;Inert gas;Pt oxidation