System design for transport applications

The following contribution concerns direct methanol fuel cells (DMFC) and their ability to use the new technology as an electrochemical device in an electric propulsion system in the future. First, a brief introduction is given regarding alternative fuels and the attractiveness of methanol as one alternative fuel in comparison with hydrogen (CHG) and synthetic fuels. In addition, the properties of the DMFC propulsion system are compared with those of systems based on CHG and synthetic fuels from a technical point of view. Second, the design of the liquid-feed DMFC system is discussed on the basis of comparison between a gaseous and a liquid-feed DMFC system. Third, the CO₂ separation process is simulated, and hardware presented. The thermal management of a DMFC stack is also modeled. A brief description of system management concludes the chapter.

Keywords: methanol; liquid-feed; alcohols; direct fuels; methanol oxidation anode kinetics; DMFC; crossover; membrane; electrocatalyst; analytical tools; degradation; lifetime