摘要 |
Ionomeric membranes comprising (per)fluorinated, se-micrystalline or amorphous, ionomeric polymers, having equivalent weight (EW) from 380 g/eq to 1,800 g/eq, which used in fuel cells, under the following conditions: membrane thickness 50 mum assembled between two electrodes catalyzed with 0.6 mg/cm<SUP>2 </SUP>Pt/C and treated with 0.7 mg/cm<SUP>2 </SUP>of Nafion(R), having a 10 cm<SUP>2 </SUP>area; hydrogen and air feeding, both at the pressure of 0.25 MPa, both saturated with water at 80° C.; cell temperature 75° C.; for membranes formed of copolymers TFE/F<SUB>2</SUB>C-CF-O-(CF<SUB>2</SUB>)<SUB>2</SUB>-SO<SUB>2</SUB>F, give the following maximum specific power (P<SUB>MAX</SUB>) values, at the indicated EW values: at EW=670 P<SUB>MAX </SUB>higher than 0.55 Watt/cm<SUP>2</SUP>; at EW=830 P<SUB>MAX </SUB>higher than 0.66 Watt/cm<SUP>2</SUP>; at EW=1,160 P<SUB>MAX </SUB>higher than 0.50 Watt/cm<SUP>2</SUP>; at EW=1,600 P<SUB>MAX </SUB>higher than 0.32 Watt/cm<SUP>2</SUP>. |