Multi‐Performance Synergistic Optimization of Sandwich‐Structured Composite Bipolar Plates Based on Polyaniline/Carbon Nanotubes@Nickel Foam

ABSTRACT Bipolar plates (BPs) are pivotal components in proton exchange membrane fuel cells, directly influencing system efficiency. Conventional metal BPs face poor corrosion resistance, while graphite BPs are limited by low intrinsic conductivity and mechanical strength. Although composite fillers offer a viable approach for enhancement, the key research difficulty involves balancing and the simultaneous attainment of uniform filler dispersion, a stable conductive network, and significantly improved corrosion resistance. Here, we report a strategy to fabricate high‐performance composite BPs using highly conductive polyaniline/hydroxylated carbon nanotube and graphite as fillers. These fillers were prepared via ultrasound‐assisted dispersion, deposited onto nickel foam, and integrated with a scaled graphite interlayer through hot‐press curing. The resulting BPs exhibit an electrical conductivity of 389.9 S/cm, a thermal conductivity of 22.62 W m ⁻¹ K ⁻¹ , and a flexural strength of 64.62 MPa. The plates also show high gas tightness, effective water management, and excellent corrosion resistance. Durability tests confirm the operational stability of the developed BPs under practical conditions.