(146d) The Miniature Direct Formic Acid Fuel Cell: Optimization and the Study of the Anode Catalyst

Small fuel cells have been proposed to replace batteries for such applications as small hand-held electronic devices, on chip sensors, implantable devices, as well as for communications [1-3]. Formic acid fuel cells are ideal, because they have a lower crossover than DMFCs [4]. This allows one to use more concentrated fuels [5-6], and practically no balance of plant. A brief overview of previous optimization of membrane thickness and fuel concentration will be given for our 4.9 mm2 fuel cell. Currently, the fuel cell can obtain 150 W-hr/l as well as a peak power density of 43 mW/cm^2. Also, work that will be presented will focus on the optimization of the catalyst ink layer. Nafion is an important binder in fuel cell catalyst inks. The proper amount needs to be added to the ink to ensure both good adhesion between the catalyst layer and the membrane, but also enough to allow for good proton and electron conduction[7-11]. Fuel Cell and electrochemical data will be presented to illustrate the effects of Nafion loading on the anode of the direct formic acid fuel cell.

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