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Publisher Summary Direct Methanol Fuel Cells (DMFCs) represents the only class of fuel cells in which one of the reactants is provided in liquid phase unlike the other, gas-fed, cell types. Owing to the comparatively easy handling of methanol, DMFCs are mostly considered for portable and mobile applications. Their reduced power density compared with hydrogen-driven Polymer Electrolyte Membrane Fuel Cells (PEMFC) usually leads to larger stack sizes at similar power characteristics. Methanol cartridges are much easier to handle than hydrogen storage media, giving them an advantage in fuel transport. As the material requirements are comparable to hydrogen-driven PEMFCs, the components employed are in general very similar or even identical to this fuel cell type. This chapter presents an introduction to the fundamental steps of the electrochemical methanol oxidation reaction and describes requirements for catalysts employed in DMFCs, followed by the gas diffusion media, flow-field considerations and finally system requirements and performance aspects. The chapter further reviews the environmental aspects in terms of carbon dioxide separation; carbon dioxide results from the complete oxidation of methanol have recently been a strong issue in terms of “green energy conversion.” Requirements for membrane materials are almost identical to the materials employed in hydrogen-driven fuel cells. |
