Abstract: To study the effect of carbon paper on self-humidifying performance of proton exchange membrane fuel cell(PEMFC), the membrane electrode assemblies(MEAs) were prepared by three types of Toray carbon papers TGP-H-028(0.28 mm), TGP-H-060(0.19 mm) and TGP-H-030(0.11 mm), and single PEM fuel cells were assembled by the TGP-H-028 carbon papers treated with PTFE latex of different mass fractions for the experiment studies of polarization and AC impedance. The results showed that the thick carbon paper of TGP-H-028 had a better self-humidifying performance than other carbon papers, and its peak power density increased 0.05 W/cm² comparing with that of thin carbon paper TGP-H-030; moreover, the self-humidifying performance of MEA increased with increasing PTFE mass fractions in the range of 20%—40%, the peak power density could increase about 0.25 W/cm². But the self-humidifying performance of the MEA with TGP-H-028 disposed by 60% PTFE was lower than that disposed by 40% PTFE. Finally, the microstructure, pore distribution, and hydrophobicity of the carbon papers were analyzed by methods of SEM, intrusion Hg measurement and surface tension measurement.

Key words: Fuel cell, Proton exchange membrane, Self-humidifying, Carbon paper, Electrode