Lightweight and conductive

The bipolar plates of fuel cells, conductive polymer compounds are being tested as promising substitute materials for graphite and metals are discussed. The conductivity required for the bipolar plate determines what fillers or mixture of fillers are selected. The bipolar plate represents an important structural as well as functional element in the fuel cell. Using metallic materials is another possibility. Metal bipolar plates are manufactured of high-alloy steel and are characterized by very good electrical conductivity as well as mechanical integrity, but have a high density and are quite susceptible to corrosion. A uniform distribution of the fillers in the bipolar plate is essential. A combination of extrusion and stamping permits economical production of bipolar plates for portable applications when the quantity does not justify the cost of an expensive multi-cavity injection mold.