Abstract
In this study, water behavior in an operating PEFC was visualized by using neutron radiography, and the cell voltage and the pressure drop between inlet and outlet of air were simultaneously measured. The PEFC is compliant with JARI (Japan Automobile Research Institute) standard PEFC. Electrode area with 50×50 mm^2 was visualized, and the cell temperature was kept at 80 ℃. The effect of geometry, i.e. single-serpentine and three-serpentine, relative humidity of air and current density were investigated. From the experiments, it can be confirmed that fluctuation of area-average water thickness in three-serpentine channel is larger than that in single-serpentine channel and water in the channel is likely to accumulate at corners of the channel in single-serpentine channel. Furthermore, movement of condensed water is strongly related with the cell voltage and the pressure drop.