• • Graphite-based bipolar plates (GBPs) constitute approximately 70% of stack volume/weight and 30% of stack cost, making material and process optimization critical for commercial PEMFC viability.
• • The review identifies that graphite particle size, morphology, and surface characteristics directly influence electrical conductivity and mechanical strength; for instance, larger flake sizes enhance conductivity but reduce mechanical integrity, necessitating a balance.
• • Filler type (e.g., CNTs, carbon black, graphene oxide, carbon fibers) and content are pivotal; multiscale filler design can achieve synergistic improvements, with specific formulations enabling electrical conductivity above 100 S/cm and flexural strength exceeding 40 MPa.
• • Molding processes (injection vs. compression molding) and resin content optimization are key to reducing gas permeability below 10^-6 cm^3/(cm^2·s) while maintaining corrosion resistance, meeting DOE 2025 targets.