Novel Membrane Electrode Assembly (MEA) Fabrication for PEMFC Operations under Non-humidified Conditions

The operation under non-humidified condition was demonstrated with novel MEA (membrane electrode assembly) for a PEMFC (proton exchange membrane fuel cell). For a conventional PEMFC operation, Pt is loaded uniformly on the whole active area of MEA. In the report, Pt catalyst was coated with a gradient on the active area of MEA. The catalyst amount was reduced gradually from cathode inlet to outlet. When the cell was fully humidified, the performance of gradient catalyst coated MEA was lower than that of the uniform catalyst coated one. However, when the cell was operated under non-humidified condition, the cell performance of the gradient catalyst coated MEA was higher than that of the uniform catalyst coated MEA. In the case of the gradient catalyst coated electrode, the amount of water which was generated at the cathode inlet site was relatively large compared to uniform catalyst coated one and the water was used to hydrate the MEA properly, resulting in higher cell performance under non-humidified condition.