Durability of Low-Pt Loading Membrane Electrode Assembly under Dynamic Driving Conditions

In this paper, a long-term durability test for 3910 h is carried out on a low Pt-loading fuel cell stack by simulating the dynamic driving cycles. The performance of a specific membrane electrode assembly (MEA) in the stack before and after the test is analyzed, revealing the high voltage decay rate of the appliance. Various electrochemical and physical characterization techniques are used to analyze the degradation mechanism of the MEA via region-based segmentation technique. The results show that the degradation of MEA performance is mainly due to the agglomeration and loss of Pt nanoparticles in the cathode catalyst. In particular, the growth of catalyst particles occurs at the inlet and outlet of the cathode. A high loss rate of Pt particles at the cathode inlet causes their aggregation at the boundary between the catalyst layer and the membrane where the loss of Pt is initiated. Finally, the migration of the unsupported Pt particles occurs due to the gravity toward the underlying cathode micro porous layer. This study had important implications for promoting the development and commercial application of cost-efficient and long-life MEAs.