Performance of the high temperature PEM membrane electrode assembly

This communication will provide details on some of the high temperature polymer electrolyte membrane (HT-PEM) membraneelectrode- assembly (MEA) performance targets most recently achieved by Danish Power Systems. These include (i) MEA performances of > 0.67 V at 0.2 A cm < sup > -2 < /sup > using dry H < inf > 2 < /inf > /Air, (ii) MEA lifetime of 12000 h at 0.23 A cm < sup > -2 < /sup > using dry H < inf > 2 < /inf > /Air with an average degradation rate of 9 μV h < sup > -1 < /sup > , and (iii) an integrated 5 kW stack/reformer system using methanol reformate as fuel. Studies using reformate have also led to promising results with an MEA performance of 0.58 V at 0.4 A cm < sup > -2 < /sup > with a degradation rate of 24 μV h < sup > -1 < /sup > using wet H < inf > 2 < /inf > (30 mol%)/Air for 500 hours. In addition to reaching these performance benchmarks, a reduction in the standard deviation for MEA performance to < 5% has been achieved through efforts aimed at improving the uniformity of the membrane and catalyst layer thicknesses.