Effect of the Anode Structure on the Stability of a Direct Methanol Fuel Cell

The stability of a direct methanol fuel cell (DMFC) was investigated by two single DMFCs with different anode structure membrane electrode assembly (MEA) under discharging at the constant current model for more than 4000 h. One of the MEAs with a catalyst coating membrane (CCM) anode electrode loads 5.5 mg cm–2 anode catalyst of Ru black loading, and the other with a gas diffusion layer coating (GDE) anode electrode loads 5.5 mg cm–2 of 60% PtRu/C. During the stability testing, DMFC with a CCM anode structure with a noble metal loading (5.5 mg cm–2) showed a 22% performance loss and that of GDE anode structure with a lower noble metal loading (3.3 mg cm–2) was 17%. Polarization curves, electrochemical measurements, and EDX (energy dispersive X-ray spectroscopy) were performed to analyze the difference of catalyst activity, internal resistance, and Ru loss between two DMFCs.