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

Abstract

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<3> 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 content in the pole plate is easier to be controlled, the sealing property to gas is good, the mechanical property is good, the thickness of the pole plate is convenient to bereduced, the preparation technology is simple, the mass production is easy, and the preparation method is significant for promoting the industrialized development of the fuel cell.

Description

A preparation method of a flexible graphite composite bipolar plate for a proton exchange membrane fuel cell technical field The invention relates to the field of proton exchange membrane fuel cells, in particular to a preparation process for flexible graphite composite bipolar plates of proton exchange membrane fuel cells. Background technique The bipolar plate is a key component in the proton exchange membrane fuel cell (PEMFC). In the fuel cell, it plays the role of distributing fuel gas and air, realizing the electrical connection between monolithic cells, taking out waste heat from the active area, and preventing gas and coolant leakage as well as facilitating water management in the battery, among other functions. In addition, the cost of the bipolar plate accounts for about 30%-45% of the total cost of the battery, and its mass accounts for 80% of the total weight, so it also has a significant effect on the mass, volume and cost of the entire PEMFC system. It can b...

AI Technical Summary

Problems solved by technology

The bipolar plate prepared by this process has good electrical conductivity, mechanical and sealing properties, but its thickness is relatively large, which has certain restrictions on the assembly and practical application of battery packs, especially for vehicles.

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