METHOD FOR ASSEMBLING DIAPHRAGM-ELECTRODE UNIT Russian patent published in 2003 - IPC

FIELD: electrical engineering; fuel cells with proton-conducting polymeric diaphragms. SUBSTANCE: novelty is that diaphragm- electrode unit is assembled by electrochemical method , that is, in pulsed mode of operation of fuel cell while reducing them with aid of plane- parallel gas-distributing plates provided with channels on their surfaces, 0.5 to 5.0 sq. mm deep, for feeding chemical agents and with insulating gaskets on their perimeter forming spaces separated relative to electrodes for feeding hydrogen and oxygen; total sectional area of all channels is 1 to 10% of electrode surface. Assembly is conducted at draft pressure of 2 to 150 kg/sq. cm and working gas pressure of 1 to 6 atm. abs. until temperature of 80 to 120 C is attained due to connection of electric load to auxiliary plates in pulsed mode with current density being from 100 mA/sq. cm to short-circuit currents. By the end of assembly diaphragm- electrode unit is checked for its current-voltage characteristics. Diaphragm-electrode unit is also proposed to be subjected to pre- assembly thermal reduction at draft pressure of 2 to 150 kg/sq. cm and at temperature of 90 to 220 C in aqueous dielectric environment or in air. In the latter case diaphragm is pre-dehydrated at 60 to 98 C. EFFECT: enhanced efficiency of using active surfaces of unit. 4 cl, 2 dwg