Proton methanol fuel cell technologies

Membranes made from homogeneously sulfonated polystyrene exhibited proton conductivity equal to that of Nafion, with methanol permeability about 70% smaller than for this ionomer. This is attractive particularly in relation to the methanol fuel cell technology (150). 

The electrocatalytic oxidation of methanol has been widely investigated for exploitation in the so-called direct methanol fuel cell (DMFC). The most likely type of DMFC to be commercialized in the near future seems to be the polymer electrolyte membrane DMFC using proton exchange membrane, a special form of low-temperature fuel cell based on PEM technology. In this cell, methanol (a liquid fuel available at low cost, easily handled, stored, and transported) is dissolved in an acid electrolyte and burned directly by air to carbon dioxide. The prominence of the DMFCs with respect to safety, simple device fabrication, and low cost has rendered them promising candidates for applications ranging from portable power sources to secondary cells for prospective electric vehicles. Notwithstanding, DMFCs were... 

All fuel cells for use in vehicles are based on proton-exchange-membrane fuel cell (PEMFC) technology. The methanol fuel-processor fuel cell (FPFC) vehicle comprises an on-board fuel processor with downstream PEMFC. On-board methanol reforming was a development focus of industry for a number of years until around 2002. Direct-methanol fuel cells (DMFC) are no longer considered for the propulsion of commercial vehicles in the industry (see also Chapter 13). 

However, the vapor pressure of molecular liquids, their miscibility with water and/or methanol and their viscous properties, lead to severe limitations in current fuel cell technology (see Section 23.2). Therefore, the development of non-liquid electrolytes with proton conduction properties close to these of hydrogen-bonded liquids is a key issue of current PEM fuel cell research. However, the fuel cell requirements do not allow much of a compromise with respect to proton conductivity, which should not drop below about ct = 5 x S cm i. Such high conduc-... 

Kreuer KD (1997, 2001) On the development of proton conducting materialspolymer membranes for technological applications. Solid State lonicsi 97 1-15 Hydrogen and methanol fuel cells. J Membr Sci 185 29-39... 

The route map is split into a number of sections based on application (stationary, vehicular and portable) and technology [primarily direct methanol fuel cells (DMFCs), proton-exchange membrane (PEM) and solid oxide... 

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