Direct methanol fuel cells: fundamentals, problems and perspectives

Abstract

Fuel cells are chemoelectric engines that convert the chemical energy of a fuel directly into electricity. The process is an electrochemical reaction akin to a battery, but unlike the battery, fuel cells do not store the chemicals internally and instead use a continuous supply of fuel from an external storage tank. Accordingly, fuel cell systems have the potential to solve the most challenging problems associated with the currently available battery systems, namely their insufficient energy at a given weight (specific energy density) or volume (volumetric energy density). Besides, while the leading battery technologies are reaching the practical limits of their energy storage capabilities, commercial fuel cells are still in their infancy. Furthermore, since fuel cells operate without a thermal cycle, they offer a quantum leap in energy efficiency and virtual elimination of air pollution without the use of emission control devices as in conventional energy conversion.