Performance evaluation of a direct methanol fuel cell (DMFC) with novel anode flow field operating with neat methanol

Abstract

This paper reports the structural effect of a novel anode flow field on the performance of a direct methanol fuel cell (DMFC) operating with neat methanol. The anode flow fields with various vaporization channel configurations, open ratios, gap aspect ratios and vaporization channel lengths are designed, fabricated and tested on DMFCs. Results show that the DMFC with an anode flow field with central vapor inlet yields better performance than that with vapor inlet in the corner. Both the open ratio and aspect ratio of the anode flow field have significant influences on cell performance. Larger open ratio and larger aspect ratio lead to more uniform reactant distribution in the in-plane direction, but can result in a lower methanol concentration in the anode catalyst layer (ACL), which makes the DMFC suffers larger polarization loss at moderate and high current densities. In addition, it is found that a longer vaporization channel facilitates the cell to work at lower temperature, which is promising to operate a neat-methanol-fed DMFC by self-heating.