Performance analysis of the ordered and the conventional catalyst layers in proton exchange membrane fuel cells

• Published in: Electrochimica acta 2006-06, Vol.51 (23), p.4934-4941
• Main Authors: Du, C.Y., Yang, T., Shi, P.F., Yin, G.P., Cheng, X.Q.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cathode; Conventional active layer; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Numerical model; Ordered active layer; Proton exchange membrane fuel cell
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2006.01.047

Two steady-state, one-dimensional models of the cathode active layer for the proton exchange membrane fuel cell, a conventional active layer model with the agglomerate structure and an ordered active layer model, have been compared. The model equations account for the Tafel kinetics of oxygen reduction reaction, proton migration and oxygen diffusion in the polymer electrolyte and gas pores. The polarization curves simulated by the ordered active layer predict a superior performance than the conventional active layer model even with lower platinum loadings. Analysis of the overpotential contributions indicates that the better performance of the ordered catalyst layer can be attributed to the reduction of concentration polarization. Simulation results also reveal that the ordered active layer gives more uniform oxygen concentration and overpotential distributions while the conventional catalyst layer shows more evenly distributed local current source. The present results will be helpful for practical fuel cell designs.