Interface engineering and rapid curing Synergistic regulation of composite graphite bipolar plates for PEMFC

The performance of bipolar plates in PEMFC directly affects their efficiency and commercial application. In this study, to address the issue of long preparation times and low production efficiency associated with traditional graphite bipolar plates, we optimize the epoxy resin curing system to significantly enhance the preparation efficiency and overall performance of composite graphite bipolar plates (CBPs). 1- o -Tolylbiguanide (OTB) is used as the curing agent, and 2-methylimidazole (2-MZ) is introduced as an accelerator, allowing the epoxy resin to fully cure in 3min–5min at 160 °C, greatly reducing the preparation time. Kinetic analysis shows that 2-MZ reduces the apparent activation energy of the curing reaction, accelerates the ring-opening of epoxy groups and the formation of the crosslinking network, and optimizes the resin molecular chain structure. As a result, the flexural strength and conductivity of the CBPs are significantly improved. Additionally, the introduction of anhydrous ethanol enhances the interfacial bonding between the resin and graphite filler, improving the conductive uniformity of CBPs. Electrochemical tests demonstrate that the optimized CBPs exhibit excellent corrosion resistance under simulated PEMFC acidic conditions, meeting the standards set by the DOE. This study provides a feasible strategy for the efficient, low-cost preparation of high-performance composite graphite bipolar plates, advancing the commercialization of PEMFCs.