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The proton exchange membrane fuel cell (PEMFC) its energy conversion rate, low-emission, high specific energy and high power density advantages are considered to adapt to future energy and environmental requirements of the ideal power source for one. Bipolar plate attributable to the fuel cell stack by weight from 60% to 80%, and the total cost of 40% to 50%, is a proton exchange membrane fuel cell is an important part. Therefore, it is looking for excellent performance and low cost bipolar plate materials and processing methods has become an important issue in the industrialization of fuel cell technology research. This thesis is mainly conducted the study of two aspects: First, the use of inorganic acids and Na do intercalation agent prepared no sulfur expanded Graphite (EG expandedView graphite,), by orthogonal experiment has been the expansion factor is greater sulfur-free expanded graphite. Means of XRD, SEM, EDS and TG-DTA analysis of expanded graphite structure, surface morphology and thermal stability were characterized. The results show that: HClO4, H3PO4 and of K2CrO4 inorganic acidic substances as oxidant and intercalation Preparation of expanded graphite method is simple, easy to get raw materials cycle is short, simple equipment, expansion of multiple general expansion of multiples in 250 to 400ml / g, and have thermal stability and good. Sodium plug novel method of expanded graphite layer preparation, the preparation process is organic matter decomposition to CO2 and H2O in the microwave heating process, less environmental pollution. Second, the porous structure of the expanded graphite good adsorption capacity oils other macromolecules, so that the thermoplastic phenolic resin (PF, phenolic resin) is adsorbed in the pores of the expanded graphite, prepared EG / PF composites. After drying steps to remove the moisture in the composite material of the EG / PF, and then subjected to compression molding. The subject of the composites prepared EG EG / PF / PF composite bipolar plates using two processes, process 1 EG / PF the composite curing agent mixed high-temperature molding, curing, and preparation of the bipolar plate; process 2 EG / PF composite material is mixed with a curing agent, the first curing, then the high-temperature molding, the preparation of the bipolar plate. And characterized by different expansion graphite content, the conductivity of the bipolar plate prepared by different processes, the flexural strength, compressive strength, hardness, density, electrochemical corrosion rate performance analysis, process 1 Preparation of a bipolar plate mechanical properties, density, corrosion resistance superior to the process of preparing a bipolar plate. And craft a prepared EG / PF ratio at 1:1 to 2:1 between bipolar plates prepared various performance reached the performance requirements of the U.S. Department of Energy (DOE) to develop bipolar plate materials.
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