Abstract
The aim of this paper focus on increasing the graphite/phenolic composite’s electricity and mechanical properties by adding Nano-metal oxide particles, and it discusses the composite’s mechanical properties after modified environmental test. We can take advantage of adding a large number of graphite powders to efficiently increase the electricity of the bipolar plates used in fuel cell, however they also decrease the mechanical properties at the same time. Bipolar plates decreased the mechanical properties when they are used in the environment of high temperature and high humid for a long time. Environment of thermal cycles also accelerated the crack propagation and decreased the mechanical properties. The results of this paper pointed that adding 3 phr Nano-ZnO or ITO particle had the best flexural strength (61.71、61.27 MPa), Izod impact strength (0.85、0.79 lb-ft/in) and tensile strength (39.24、39.96 MPa), but these mechanical properties couldn’t be increased when adding 5 phr Nano-metal oxide particle with the coming of the aggregation of Nano-metal oxide particle. The porosity reduced with increasing Nano-ZnO or ITO content, but the specific gravity increased with increasing Nano-ZnO or ITO content. All of these spacemen could keep gastight under the gastight test, and the corrosive current were less than 16 µA/cm2. The spacemen under the environment of 85 0C/RH85 % for 168 hr decreased flexural strength about 1.5~4.6 % than that in the normal environment. The spacemen after 500 thermal cycles (-40~1250C) decreased flexural strength about 10 % than that in the normal environment.