Performance degradation of 1 kW proton exchange membrane fuel cell stack using graphitized carbon supported Pt nanoparticle catalyst
By Pan, Fengwen; Li, Jun; Gao, Ying; Li, Bing
Published in Journal of Power Sources
Journal of Power Sources
2020
Abstract
Graphitic carbon-supported Pt nanoparticles (Pt/GC) are used as high durability catalysts in 1 kW proton exchange membrane fuel cell (PEMFC) stack. Accelerated degradation tests (ADT) with different protocols at the half-cell and single cell level show that Pt/GC catalysts exhibited better durability than commercial Pt/C. After 458 h of dynamic drive cycle durability testing, the PEMFC stack exhibits a voltage degradation rate at 1000 mA cm?2 of 5.3% and 85 ?V/h. The results show that the majority of degradation was due to the contact angles of the hydrophilicity of the catalyst layer (CL) and the substrate layer (SL) is enhanced, which means the decrease in PEMFC stack durability also comes from the increase in mass transfer resistance and the reduction in the water management capacity of the cell. Partly, another reason is the collapse of the CL, which comes from the uneven assembly force and the structural change of CL. However, the structure and the size of the Pt/GC catalyst and electrochemically active surface area (ECSA) of CL is found hardly changed after 458 h, which indicates excellent stability of the catalyst and MEA under these practical conditions. Herein, this further supports that Pt/GC catalyst makes practical PEMFC applications possible.