Design and simulation for improved performance via pump-less direct ethanol fuel cell for mobile application

The advancement of direct ethanol fuel cells (DEFCs)as portable power sources demonstrated a significant challenge since the power output is still far from the acceptable standards, mainly due to the slow kinetics of the ethanol oxidation reaction (EOR)via the passive mode. While the active system presented higher power output but ends up with a bulky system including all the external mechanical devices. Thus, this work proposed a pump-less DEFC to replace the conventional passive and active DEFC systems to achieve both power generation and device portability. The electrochemical results showed that pump-less DEFCs generated comparable power output with active-feed DEFCs. Computational fluid dynamic (CFD)simulations of the anode flow field for pump-less DEFCs were carried out using three types of flow field designs with different fuel outlet directions. The results indicated that a winding outlet (L-shaped)channel produced the lowest fuel discharge velocity as a result of a high static pressure drop along the channel.