In-situ measurement in through-plane direction in PEMFC

Water management is a large issue for putting PEMFC to practical use. Appropriate water management enables us to suppress the drying in PEM (Polymer Electrolyte Membrane) and the flooding in GDL (Gas Diffusion Layer), which degrade the performance of PEMFC Against the background of importance for the water management, we challenged to develop the measurement method to grasp the water behavior in PEMFC Especially, we focused on through-plane direction measurement, because the through-plane direction in cell has major role for the transport of mass, heat and electric charge in the cell. We developed the three methods to measure the water in cell directly or indirectly: cross sectional cell: micro NMR-sensor array: micro thermocouple array. These three methods successively captured the distribution of the liquid water in GDL, the water content in PEM and the temperature in cell. (Figure Presented) The data obtained help us to give the possible mechanism of how the water in cell impacted the cell voltage.