Fabrication and characterization of a passive silicon-based direct methanol fuel cell

This paper reports on the fabrication and characterization of a passive silicon microfabricated direct methanol fuel cell (μDMFC). The main characteristics of the device are its capability to work without complex pumping systems, only by capillary pressure, and the fact that its performance is not affected by the device orientation. A simple fabrication process based in deep reactive ion etching (DRIE), allows obtaining a reliable and low-cost final device. The device consists of two silicon microfabricated plates mounted together with a commercial membrane electrode assembly (MEA). The impact of current collector design on microfuel cell performance is explored and current–voltage (I–V) and current–power (I–P) curves of the device at different methanol concentration and orientation are presented. Optimal performance was obtained for methanol concentrations between 3 and 5 M, achieving a maximum power density of 12 mW/cm². The results obtained in this work demonstrate the feasibility of the device and give a guideline for design and conditions optimization.