Numerical study on performance of HT-PEMFC with gradient design of Pt loading

In this paper, the spatial distribution of overpotential and current density of high temperature proton exchange membrane fuel cell (HT-PEMFC) with gradient design of platinum (Pt) loading is studied. Three Pt loading gradient distributions are considered: along the thickness direction of the catalyst layer (CL), along the flow direction and the bidirectional linear gradient distribution. The results show that the increase of the Pt loading near the membrane could improve the fuel cell performance and catalyst utilization when the total amount of Pt in CL consistent. In addition, the increase of Pt loading along the flow direction provides a more uniform current density for the fuel cell, but lower cell performance. The bidirectional linear gradient distribution of Pt loading is studied, and the results show that the current density distribution is more uniform, but the cell performance is slightly improved. Therefore, the results demonstrate that the reasonable distribution of Pt loading can improve the cell performance and improve the uniformity of current density, which is of great significance to improve the utilization of catalyst.