In the attempt to make low cost conducting polymer composite materials for fuel cell / battery applications, polypropylene (PP) with graphite (Gr) and other carbon black/ nanotubes hybrid materials were investigated. The development of crystalline structure in polypropylene (PP) graphite composite was studied with respect to composition and processing conditions. The DSC and XRD data confirmed the preferential nucleation and beta crystalline phase formation for the binary PP-Gr composites. There was dramatic increase in the electrical conductivity by addition of small amount of thrid component (CNT <5%) to the binary PP-Gr composite even at low graphite loading of 10%. Impedance spectroscopy analysis showed that the interfacial capacitance, with the addition of 2.75 wt% CB in PP-7 wt% graphite, increases to 52 pF from 31 pF for PP-7 wt% graphite proving the occupation of CB particles in the interspaces of graphite particles. The results of electrical conductivity were correlated with the nucleation and crystallization of the beta phase of PP by graphite flakes leading to interfacial resistive layer in binary composites while suppression of these effects in the ternary composites.