Flexible graphite-based integrated anode plate for direct methanol fuel cells at high methanol feed concentration

An integrated anode plate suitable for operating direct methanol fuel cells (DMFCs) at a high methanol feed concentration is reported. This anode structure which was made of flexible graphite materials not only provides dual role of liquid diffusion layer and flow field plate, but also serves as a methanol blocker by decreasing methanol flux to the interface of catalyst and membrane electrolyte. DMFCs incorporating this new anode structure exhibited a much higher open circuit voltage (OCV) (∼0.51 V) than that (∼0.42 V) of a conventional DMFC at a 10 M methanol feed. Cell polarization data show that this new anode structure significantly improves the cell performance at high methanol concentration scenarios (e.g. 12 M or above). Moreover, this new design greatly simplifies the anode structure and offers a promising approach in running passive-mode DMFC at high methanol feed concentrations.