EFFECTS OF GRAPHITE/POLYPROPYLENE ON THE ELECTRICAL CONDUCTIVITY OF MANUFACTURED BIPOLAR PLATE

Conductive polymer composite (CPC) has been used on bipolar plates by compression and injection molding methods. The CPC material comprises 25% polypropylene and 75%graphite with size variation (40, 100, 150, and 200 μm) according to particle size dispersion test. The composite is mixed using an internal mixer to obtain a homogeneous mixture at a process temperature of 200 °C. Electrical conductivity tests are performed on each particle size composition. The highest electrical conductivity produced by compression and injection molding methods is 17 and 12 S/cm, respectively. These values are both obtained on a 40 μm graphite filler. Results show that the type of manufacturing process affects the value of electrical conductivity using the same material.