燃料电池用集流碳板的浸渍研究

STUDY OF IMPREGNATING POLYTETRAFLUOROETHYLENE IN GRAPHITE FOR USING AS COLLECTOR OF FUEL CELL

采用浸溃聚四氟乙烯分散液的方法处理普通石墨板,使之能用于燃料电池的集流碳板。分析了聚四氟乙烯分散液浸渍燃料电池用集流碳板的可行性,优化了浸渍工艺。在5 Pa的真空下,使用70％(质量分数)聚四氟乙烯分散液,加压至O.6MPa,保持10 h的条件下,一次浸溃即可使得集流碳板的气孔率由18.20％降低到3.29％,浸渍后的集流碳板在H2压力为0.3 MPa.下无渗漏。浸溃工艺没有影响电阻率。SEM电镜表明:实验条件下聚四氟乙烯的浸渍深度可达到2.50 mm。基本满足了燃料电池用集流碳板的需要。

Ordinary graphite plate was impregnated by PTFE(polytetrafluorethylene) dispersing solution to make it be used as fuel cell collector. The impregnation process was investigated in feasibility and optimized. Porosity of graphite is dropped to 3.29 percent from 18.20 percent by once impregnation on the processing condition of 5 Pa vacuum, 70 percent in mass of PTFE ,0.6 MPa air pressure and holding lOh. The graphite plate is no leakage of Hj even at 0. 3 MPa after impregnation of PTFE. There is no effect on the graphite resistivity in impregnation process. SEM results for graphite show that the impregnation depth attained 2.50 mm. Impregnation process fundamentally meet the need of fuel cell graphite collector.