| 초록 |
Generally, the membrane-electrode assemblies for a liquid-feed direct methanol fuel cell (DMFC) are fabricated by using a Nafion solution and tape-casting, with unsupported Pt-Ru as an anode catalyst and carbon supported 40 wt.% Pt as a cathode catalyst. Preparation of polymeric composite bipolar plates has been relying on high loadings of discrete and conductive graphite/carbon filler particles to meet fuel-cell plate conductivity targets. Unfortunately, at these loadings, the plate materials are inherently brittle, resulting in the high scrap rates and the inability to mold thin plates required for high stack volumetric power densities. In this work, therefore, low loading of high-aspect-ratio conductive fillers, such as PAN-based nanofibers prepared by electrospinning is used to simultaneously increase the plate conductivity and toughness, and to reduces the bulk resistance in the current-flow direction. To evaluate the fracture toughness of the bipolar plates, analytical expression for critical stress intensity factor (KIC) may be characterized by single edge notched (SEN) test in three-point flexure.
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