A novel channel design and heat and mass transfer analysis of fuel cells

In this study, a novel partially separated-partially coupled cathode channel (PSPC) of proton exchange membrane fuel cell (PEMFC) is developed on the basis of the PEMFC with independent cooling channel, in order to accelerate the removal of liquid water and maintain the overall water balance. The novel cathode channel is numerically investigated by a 3D PEMFC model. The research shows that the PEMFC with PSPC can accelerate the water removal at the cathodic outlet side and improve the uniformity of water and heat distribution as the length of partition ( "L ") declines. When the L = 25 mm, PEMFC with PSPC can have a 13.5% higher current density than PEMFC with independent cooling channels. According to the analysis of local mass transfer for PSPC, the local water axial diffusion transport at coupled channel section evidently improves to induce water lateral diffusion transport of the separated channel section. This water transport mechanism of PSPC can also be adjusted by the cooling channel height, but the water balance should be considered. The PEMFC without partition easily leads to severe water imbalance. Thus, the current density of PEMFC with L = 25 mm is higher 15.9% than that without partitions under 1.4 mm total channel height of cathode.