Elsevier, International Journal of Hydrogen Energy, 13(36), p. 8088-8093, 2011
DOI: 10.1016/j.ijhydene.2011.01.109
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A co-planar micro Direct Methanol Fuel Cell (mDMFC) configuration was designed, devel-oped and tested. The system geometry consisted of anodic and cathodic micro-channels arranged in the same plane. Firstly, micro-channels for a uniform distribution of oxygen and methanol were designed and realized on a polymeric substrate of polycarbonate. Then, the deposition of the catalytic elements inside the micro-channels by a spray-coating technique was carried out. Micro-channels were then covered by a catalyzed membrane containing separate anode and cathode layers. Different cell configurations were built, tested and evaluated. It was observed that the open circuit voltage varied significantly as a function of the membrane humidification degree and distance between anode and cathode channels in this planar design. In the presence of a large distance between the anode and cathode channel, the OCV reached 0.97 V. This high OCV reflected the absence of methanol cross-over due to the specific planar configuration. Regrettably, the overall cell impedance (ohmic and polarization resistance) limited the performance. A maximum power density of 1.3 mW cm À2 (active area) was achieved at room tempera-ture with the smallest distance between anode and cathode (0.25 mm).