The Problems to be Solved in Future DMFC

At the Korea Institute for Science and Technology, the operation of a six-fuel-cell stack, having a total power of 50 W, was investigated. The stack was fed with a 2 M methanol solution. The fuel cell was supposed to work at ambient temperature, but internal heat production raised its temperature to above 80°C. Using oxygen, a maximum power of 254 mW/cm was attained. With air this value was 85 mW/cm.  

Quite in contrast to polymer electrolyte fuel cells, and despite the large volume of research performed, direct methanol-type fuel cells are still not in commercial production or wide practical use. Indeed, the true performance of direct methanol fuel cells is hard to assess. The experience gathered in the tests of individual samples, performed under a variety of conditions, does not give a clear reliable picture of fuel cell s performance when used for different needs. For such an assessment, one would need statistical data obtained from tests on a sufficiently large number of cells of any single type, and accounting for all cell parameters and test conditions. 

Yet even now one potential area of application can be recognized distinctively. This is for relatively low-power energy sources (no more than 20 W) in electronic equipments such as notebooks, cameras, video cameras, DVD players, some medical devices, and so on. In these areas, direct methanol fuel cells, taking up little space, should replace the disposable or rechargeable conventional batteries used at present. 

Another potential field of application for direct methanol fuel cells, that of power sources for electric vehicles, is, so far, very remote. A large amount of research and engineering work still has to be done to master this application, mainly, work aiming at improving their technical and economic parameters to solve the particular problems 

The production volume of direct methanol fuel cells and their long-term testing results are yet insufficient for an estimate of the lifetime of such fuel cells. Even so, the researchers mainly look at all the major reasons giving rise to the gradual performance drop and/or premature failure of these fuel cells. The reasons for performance drop 

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