Embedded self-circulation of liquid fuel for a micro direct methanol fuel cell

This paper introduces a micro direct methanol fuel cell (μDMFC) with an embedded self-pumping mechanism to deliver liquid fuel. The fuel is propelled by the CO
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bubbles generated by the fuel-cell electrochemical reaction, and the bubbles are removed from the system during the selfpumping process. Furthermore, the pumping rate is selfregulated by the reaction, i.e., by the electric load. By eliminating the need for a pump and gas/liquid separator, our design allows much simpler fuel-cell systems, which is especially beneficial for miniaturization. Although we test with μDMFC in this paper, the mechanism applies to other membrane electrode assembly (MEA)-based fuel cells with organic liquid fuels as well.