Studies On The Composite Membrane And Mea For PEMFC

Membrane Electrode Assembly (MEA) is the key part of the Proton Exchange Membrane Fuel Cell (PEMFC), and mainly consisted of proton exchange membrane, electrocatalyst, and gas diffusion layer. Preparation and optimization of MEA are the pivotal techniques for PEMFC. The MEA's structure and fabrication technology not only determine the performance of PEMFC, but also affect on reducing cost, improving power density and energy density, and accelerating their commercialization. To satisfy the request of the development of fuel cell, a new fabrication of membrane has been put forward, and a new fabrication method of MEA has been designed in this thesis.As for the fabrication of the proton membrane, firstly, the scrap perfluorsulfonic acid ion exchange membrane was dissolved in the combined solvent of water and alcohol at high temperature and high pressure, and the reclaimed perfluorsulfonic acid resin solution was obtained. Then FYPFSA solution (FuYuan's Perfluorsulfonic Acid solution) was introduced to improve the film forming property of the reclaimed perfluorsulfonic acid resin solution. In this paper, a perfluorsulfonic acid composite membrane was prepared with mixed perfluorsulfonic acid resin solution and PTFE as substrate. The chemical performance and electrochemical performance of composite membrane were also studied. The results show that the properties of the composite membrane of CM1 are a litter lower than those of Nafion membrane. However, the composite membrane is rather promising to have application in PEMFC on the basis of further improvement on performance of composite membrane owing to low cost.As for the MEA, a new fabrication method of direct pasting has been put forward to prepare MEA in this thesis. The platinum loading of PEMFC electrode is 0.13 mg·cm-2. The effect of the preparation condition of MEA, the components of catalyst layer and different diffusion layer, electrode structure and operation condition on the PEMFC performance are evaluated by means of voltage-current density plot of the cell, SEM and so on. The membrane prepared with the reclaimed perfluorsulfonic acid resin solution has developed the preparation methods of proton exchange membrane, which is beneficial to economize the material and decline the cost. Compared with mechanical hot pressing, the direct method of pasting have the advantage of simple technique, little limited factors and efficient industrialization.The above work has theoretic and practical value to reduce the cost of both the membrane and MEA of PEMFC.