对预制PAN基炭纤维纸进行树脂浸渍、模压和高温热处理,制备燃料电池用炭纸。借助SEM和XRD等技术研究了炭纸的微观结构和石墨化度。分别用压差法、四探针电阻法和拉伸测试测得炭纸的透气率、面电阻率和拉伸强度。结果表明:增加PF树脂炭含量可以提高炭纸的体积密度和拉伸强度,但导致透气性能下降。树脂炭含量的增加也有助于炭纸形成发达的三维网络状结构,炭纸的导电性能得到改善,炭纸整体石墨化趋势有一定的加强。当PF树脂炭含量为54%时,炭纸透气率为2050mL·mm/(cm2·h·mmAq),密度为0.48g/cm3,面电阻率21.1mΩ·cm,石墨化度58%,抗拉强度达到15MPa,基本满足炭纸的应用要求。
Carbon paper for preparing proton exchange membrane fuel cell (PEMFC) was made by impregnating PAN-based carbon fiber prefab compact with PF resin, moulding and high temperature heat treatment. Microstructure characteristics and degree of graphitization of carbon paper were analyzed by SEM and XRD. Gas permeability, electrical property and tensile strength of the the carbon paper products obtained were measured by the differential pressure method, the four-probe technique and tensile test, respectively. The results indicate that with the increase of PF resin char content in the carbon paper, gas permeability decreased whereas bulk density and tensile strength increased. The increase of PF resin char content also enhanced the formation of the three dimensional conductive network in carbon paper thus improved both the overall graphitization tendency of carbon paper and its electrical property. When the PF resin char content was 54%, the properties of carbon paper were as follows: gas permeability was 2050 mL·mm/(cm2·h·mmAq), bulk density 0.48 g/cm3, in-plane electrical resistance 21.1 mΩ·cm, degree of graphitization 58%, tensile strength 15 MPa, which basically satisfied the application requirements.