Thermal conductivity in the three layered regions of micro porous layer coated porous transport layers for the PEM fuel cell

In this study we have used X-ray computer tomography (XCT), scanning electron microscopy (SEM), and thermal conductivity measurements to show that a MPL coated PTL is actually a three layered structure where the PTL is on one side, the MPL on the other, and a composite region consisting of the MPL as a matrix with the PTL fibres in the middle. We have shown that the thermal conductivity of the MPL-PTL-composite region is much larger than for the two others and that temperature differences inside this layer can be neglected compared to the regions where it is MPL-only and PTL-only. We have also shown that the MPL has a significantly lower thermal conductivity than the other two layers. In light of this research, the MPL of the commercial SGL should be integrated into the GDL in order to have lower temperature deviations in the PEMFC. A relevant literature review is included.