High Power Density Fuel Cell.

An exploratory development program continuing the investigation of high power density hydrogen-oxygen fuel cell technology was conducted. An evaporatively cooled four-cell power section was designed, fabricated, and successfully tested at a steady-state power density exceeding 1500 watts per square foot, about 10 times the power density of conventional space fuel cell. The High Power Density HPD power section fabricated and tested consisted of a stack of four hydrogenoxygen, alkaline electrolyte, low-temperature, matrix fuel cells of 0.14 sq ft active area. Externally fed wick evaporator units between cells removed heat by evaporation of water at controlled pressure and temperature. Product water from the fuel cell reaction was vented to the atmosphere. Over 300 cell-hours have now been accumulated at high power density. Author