초록 |
Composite films, which can be applied to the bipolar plates of redox flow batteries and fuel cells, were fabricated via a tape-casting process that used a slurry of graphite, CNT, and resin materials. The slurry was made of 25∼45 wt% conductive filler and 55∼75 wt% PVB binder solution. The effects of the shape and physical properties of the graphite were investigated with regard to the dispersion behavior and flow of the slurry on the carrier film of the tape-casting device. As a result, the acicular graphite showed a good dispersion property with the resin of the PVB binder, as compared to spherical graphite. The composite film with acicular graphite showed a lower resistivity than that of a film with spherical graphite. The effect of adding a small amount of CNT to the composite film was also studied. The specific resistance of a composite film with acicular graphite was improved from 321 to 158 mΩ.cm by adding 0.2 wt% of CNT additive to the slurry composite of the graphite and resin. |