Microscale fuel cell fabrication

To build an efficient, high-quality microscale fuel cell, microfabrication techniques need to be combined with appropriate materials such as Nation based membrane electrode assemblies (MEAs). These techniques must be able to produce three-dimensional structures, allow reactant and product flow into and out of the device, process appropriate materials, and should be of low cost. Fortimately, traditional thin film techniques can be modified for microscale fuel cell fabrication, while maintaining their advantages of surface preparation, sensor integration, and finishing or packaging. In addition, other techniques are also available and are discussed in the following sections. 

Some common ways of fabricating the MEA for microscale fuel cells include hot pressing the membrane onto preformed electrodes or hot pressing a complete MEA onto a substrate, screen printing a membrane onto a substrate and depositing the electrodes on either side, and using spin deposition to deposit the membrane followed by electrode deposition. 

In designing a microscale fuel cell, there are several considerations that need to be accounted for. These include the following is the fuel cell to be completely active or passive will it operate at room temperature or elevated temperatures will the fuel be at atmospheric pressure or elevated pressure will external humidification be required and finally, will the fabrication techniques... 

Yeom et al (Univ. of Illinois) reported the fabrication of a monolithic Si-based microscale MEA consisting of two Si electrodes, with catalyst deposited directly on them, supporting aNafion - 12 membrane in-between [38]. The electrodes were identically gold-covered for current collecting, and were also covered with electrodeposited Pt black. The electrodes and the Nafion membrane were sandwiched and hot-pressed to form the MEA. The complete fuel cells were tested with various fuels H2, methanol and formic acid and reached 35 mW cm , 0.38 mW cm and 17 mW cm respectively at RT with forced... 

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