Direct Methanol Fuel Cells: Technological Advances and Further Requirements

Abstract

The direct methanol fuel cell (DMFC) has been considered as the ideal fuel cell system since it produces electric power by the direct conversion of the methanol fuel at the fuel cell anode. This is more attractive than the conventional hydrogen fuelled cells, particularly for transportation applications, which rely on bulky and often unresponsive reformer systems to convert methanol, or other hydrocarbon fuels, to hydrogen. However, commercialisation of tho DMFC has been impeded by its poor performance compared with hydrogen/air systems, the major limitation being the anode performance which requires highly efficient methanol oxidation catalysts. Such catalyst materials have been sought, and it appears that only platinum-based materials show reasonable activity and the required stability. The recent application of proton exchange membrane electrolyte materials has extended the operational temperature of DMFCs beyond those attainable with traditional liquid electrolytes, and this has led to major improvements in performance over the last five years. This article describes some key work tackling the above limitations and suggests that the DMFC is approaching the stage where it may become a commercially viable alternative to hydrogen/air systems.