Performance And Degradation Of PTFE/Nafion Composite Proton Exchange Membrane

Proton exchange membrane (PEM) is one of the key materials in the PEMFC. The development of PEMFC closely depended on the development of the proton exchange membrane. The pioneer proton exchange membrane is the polystyrene -sulfonic membrane. With the development of PEMFC, the polystyrene-sulfonic membrane was substitute gradually by Nafion membrane which made in Dupont Company. The primary element in Nafion membrane is all-fluorid-sulfonic resin. Recently, the mostly development in PEMFC was correlate with the application of all-fluorid-sulfonic resin. Thus it is very important to develop the composite membrane base on all-fluorid-sulfonic resin. The composite membrane can reduce the price of proton exchange membrane, as well as enhance the performance of proton exchange membrane.Now many research organization adopt a new technique to manufacture a kind of Nafion/PTFE composite membrane. They fill the PTFE membrane which has many empty hole with Nafion resin. The PTFE membrane work to support and enhance the main membrane, it reduce the dosage of the Nafion resin which reduce the cost of the proton exchange membrane, enhance the mechanical intensity, and improve the performance of the proton exchange membrane. Wuhan University of Technology produce successfully the Nafion/PTFE composite membrane, which thickness only half of the Nafion211 membrane, the mechanical intensity is double of the Nafion211 membrane, and its conductance is about with the Nafion211 membrane. The performance of the cell which using with the Nafion/PTFE composite membrane as the proton exchange membrane excelled the performance using with the Nafion membrane.In the circulate course of the PEMFC, the membrane electrode assembly be erode in the complex environment which include water and gas in cell. The proton exchange membrane is the hard core in the PEMFC, its degradation influence directly the degradation of full cell. Now membrane degradation become hotspot in the research of the full cell, the usable proton exchange membrane must have good wear and can withstand the degradation in physical and chemic condition. Thus the research of the degradation of the Nafion/PTFE composite proton exchangemembrane is must become important aspect.This paper expatiated the method of produce the Nafion/PTFE composite, proton exchange membrane and tested the performance of the composite membrane. Through the test we find that the physical and chemic performance of the membrane is better than the Nafion membrane, such as the mechanical intensity, conductance, cell performance. We also researched the degradation of the composite membrane, the degradation include physical degradation, chemistry degradation and electrochemistry degradation. The conclusions of the experiments prove that Nafion/PTFE composite proton exchange membrane has excellent resist degradation in physical and chemic environment.The results of the experiments indicate the Nafion/PTFE composite proton exchange membrane have excellent performance and have good resist degradation in full cells.