Transient modeling and analysis of a passive liquid-feed DMFC

A two-dimensional, transient, multi-phase, multi-component model has been developed for a liquid-feed DMFC delivery system including the fuel cell itself. The model considers the mass transport in the feed delivery system attached to the anode inlet of the fuel cell, and the effect of coupled heat and mass transfer under ambient conditions. The results are compared with the existing experimental data with a high level of agreement. The effects of feed methanol concentration in the reservoir and current density on mass transport and performance of DMFC system are revealed. When initial feed concentration in the reservoir decreases, methanol crossover is minimized, but the duration of cell performance is shortened and fuel cell temperature decreases. The anodic overpotential and its increasing rate become higher, while the decreasing rates of solution leftover and methanol concentration in the reservoir become lower. When current density increases, the duration of the cell performance is shortened. While the anodic overpotential and its increasing rate, cell temperature, decreasing rates of methanol crossover, solution leftover and methanol concentration in the reservoir increase.