BEI HOHER TEMPERATUR UND HOHEM DRUCK CHEMISCH BESTAENDIGES DICHTUNGTUNGSMATERIAL

摘要

A seal material especially adapted for phosphoric acid fuel cell stack sealing is described comprising an unfilled, unoiled high molecular weight polytetrafluoroethylene. Although the seal material is especially adapted as the regular seal around the plenums separating the oxygen and hydrogen gas inlets and outlets, it can also be used as a plenum or stack crack sealer. The material provides seal integrity and stability at temperatures in excess of 400 DEG F. (204 DEG C.)., e.g. 400 DEG F. to 450 DEG F. (204 DEG C. to 232 DEG C.), in a corrosive chemical environment at differential pressures above 50 psi (e.g. 50 psi to 80 psi). It can be used in electrochemical cells in general where high temperature, high pressure, corrosive environments prevail.