SEALING DEVICE FOR PREVENTING ENTRY OF PHOSPHORIC ACID INTO FUEL CELL COOLING PLATE AND METHOD OF COVERING COOLING PLATE END WITH SHEET

摘要

PROBLEM TO BE SOLVED: To provide a sealing device for preventing entry of phosphoric acid into a fuel cell cooling plate and a method of covering a cooling plate end with a sheet for preventing the entry of phosphoric acid into a cooling base plate and the leakage of water due to the phosphoric acid corrosion of a cooling pipe and preventing the absorption of phosphoric acid into an electrode substrate. SOLUTION: The sealing device for preventing the entry of phosphoric acid into the fuel cell cooling plate comprises a plurality of cells having a phosphoric acid electrolyte and the cooling plates, provided for each preset number of cells, laminated via separators, the cooling plates having side portions and outer periphery end face portions covered with a heat-resistant and phosphoric-acid resistant sheets 8, and casing seal materials 12 arranged on the outer periphery end face portions of the cooling plates between the cooling plate and the separator. The separators 10, 11 adjacent to the easing seal materials 12 have treated films, for example, fluororubber coatings 14 or fluororesin hot-melted membranes, for giving smoothing treatment to the uneven surfaces of the outer periphery end face portions.