Performance study of μDMFC with foamed metal cathode current collector

Abstract

Micro Direct Methanol Fuel Cells (μDMFCs) often have application in moveable power due to their green and portable nature. In a μDMFC's structure, a current collector of the μDMFC needs to have high corrosion resistance such that the μDMFC can work for a long time in a redox reaction and respond to variable environmental conditions. To this end, four cathode current collectors were prepared. The materials selected were foam stainless steel (FSS) and foam titanium (FT), with fields of hole type and grid type. The performance of μDMFC with different cathode collector types was investigated by I–V–P polarization curves, Electrochemical Impedance Spectroscopy (EIS), and discharge test. The experimental results show that the maximum power density of the hole-type FSS cathode current collector μDMFC (HFSS-μDMFC) is 49.53 mW cm⁻² at 70 °C in the methanol solution of 1 mol L⁻¹, which is 70.15% higher than that of the hole-type FT cathode current collector μDMFC (HFT-μDMFC). The maximum power density of the grid-type FSS cathode current collector μDMFC (GFSS-μDMFC) is 22.60 mW cm⁻², which is 11.99% higher than that of the grid-type FT cathode current collector μDMFC (GFT-μDMFC). The performance of the HFSS-μDMFC is optimal in the methanol solution of 1 mol L⁻¹.