Research On The Preparation And Properties Of The Proton Exchange Membrane Fuel Cell

As energy conversion device, proton exchange membrane fuel cell (PEMFC) has attractted worldwide attention due to its diversity and persistent. As a important component of PEMFC, gas diffusion layer (GDL) is usually made with carbon paper because of its structure and performance can make significant influence on the performance of the fuel cell. Basing on impregnation-molding preparation process, in this paper, a lot of explore and try on the carbon paper preparation had been done, and the effect of graphitization temperature on the basic properties of carbon paper has been researched.Using phenolic resin as impregnant, and then fabricating carbon paper by impregnation-molding technology, we investigated on the effect of graphitization temperature on the properties of carbon paper, the results shown that:with temperature increasing, the density is increased, then porosity, permeability and tensile strength become low. And found that flat electrical resistivity decreased and thermal conductivity increased due to the degree of graphitization of carbon paper which increasing with the graphitization temperature increasing. When the graphitization temperature2500℃, using hydrogen and oxygen as the fuel and oxidant respectively, the output voltage can up to0.532V with the current density2106mA·cm-2.Using carboxyl-terminated modifier (CTBN) modified phenolic resin as impregnant, we researched on the effect of CTBN content on the structure and properties of carbon paper, the results shown that:with CTBN addition amount increasing, porosity, permeability and conductivity of carbon paper are increased, tensile strength and bending strength are both first increased and then decreased, resistivity are decreased. When the CTBN content30wt%, mechanical performance of carbon paper to achieve optimal value, the other performance are as follows:porosity65.6%, permeability2130ml·mm·cm-2·hr-1·mmAq-1, resistivity23.2mΩ·cm, tensile strength30.14MPa, bending strength68.15MPa, compared with Toray carbon paper, respectively increased by 17%and21%, the output voltage can up to0.513V with the current density2010mA·cm-2. We also found that integration of fiber/matrix play a main role on the conductivity of carbon paper.Using conductive carbon black (CB) modified phenolic resin as impregnant, we researched on the effect of CB content on the structure and properties of carbon paper, the results shown that:with CB addition amount increasing, porosity, permeability are decreased, tensile strength first increased and then decreased, and resistivity first decreased and then increased. When the CB content6wt%, resistivity15.72mΩ·cm, tensile strength36.82MPa,22.4%、39.8%higher than that have no CB. the output voltage can up to0.502V with the current density1156mA·cm-2.