High power density fuel cell for aircraft high power, supplemental. Technical report, 1 Apr--31 May 1975

Power Systems Division has conducted a two-month program to investigate the effect of increased operating pressure on the performance of lightweight high power density fuel cells. A lightweight cell had been operated during previous investigations at 60 psia to power densities as high as 2320 watts/sq ft. In this program the capability was evaluated at pressures of 60, 90, 120, 150, and 180 psia. Increasing operating pressures to 180 psia increased cell power density to 3890 watts/sq ft. Endurance tests verified stable cell operation at the increased power density levels. These tests show that operation of high power density fuel cells at higher than current baseline pressure levels can significantly improve cell performance and reduce powerplant and power system weight and volume. (GRA)