Preparation method of flexible graphite composite bipolar plate of proton exchange membrane fuel cell

The invention relates to a preparation method of a flexible graphite composite bipolar plate of a proton exchange membrane fuel cell, which comprises anode flow field, a cathode flow field and a water plate made of flexible graphite plates, which are assembled into a bipolar plate with a sealing frame and a partition plate. The method is that firstly low density flexible graphite plates are prepressed into plates with the density being of 0.65 to 0.75 g/cm under vacuum, then the plates are dipped in low viscosity resin solution under vacuum, after surface treatment and drying, the plates are pressed through a roll or a die out the flow field, and a flow filed and a water plate made of polymer/flexible graphite composite plates is obtained after the plates are solidified. At last, the flow filed and the water plate made of the polymer/flexible graphite composite plates with the sealing frame and the partition plate are assembled into a bipolar plate. The preparation method has the advantages that the resin con