Method for preparing fuel cell membrane electrode

Abstract

The invention provides a method for preparing a fuel cell membrane electrode. The preparation method comprises the following steps: (a) respectively coating cathode catalyst slurry and anode catalystslurry on one side face of a microporous layer of a tabulate gas diffusion layer having the microporous layer, so as to form a cathode gas diffusion electrode and an anode gas diffusion electrode after drying; (b) coating electrolyte on one side face of a catalyst of the cathode gas diffusion electrode and/or the anode gas diffusion electrode obtained in the step (a); and (c) respectively placingthe cathode gas diffusion electrode and the anode gas diffusion electrode obtained in the step (b) on both sides of a supporting material, making the side face coated with the electrolyte or the sideface coated with the catalyst of the cathode gas diffusion electrode or the anode gas diffusion electrode face to the supporting material, and laminating the same with the tabulate supporting materialto form the membrane electrode. The novel process has the advantages of both CCM and GDE processes, can greatly improve the performance of the membrane electrode and prolong the service life of the membrane electrode, and meanwhile has a relatively low production cost.

Description

technical field [0001] The invention belongs to the technical field of fuel cells, and in particular relates to a method for preparing fuel cell membrane electrodes. Background technique [0002] A fuel cell is a power generation device that directly converts chemical energy into electrical energy through an electrochemical reaction. It has the characteristics of high energy conversion efficiency and environmental friendliness. It is considered to be the preferred clean and efficient power generation technology in the 21st century. [0003] Membrane electrodes are where electrochemical reactions take place, where chemical energy in the fuel is directly converted into electrical energy. Membrane electrodes are usually formed by stacking five layers of cathode gas diffusion layer, cathode catalytic layer, proton exchange membrane, anode catalytic layer, and anode gas diffusion layer. Membrane electrode preparation methods are divided into catalyst coated on the proton exchang...

AI Technical Summary

Problems solved by technology

The main advantage of the CCM process is that it has an excellent interface structure between the proton exchange membrane and the catalytic layer, and the discharge performance is high; the disadvantage is that the process is difficult to realize and the production efficiency is low, which is mainly due to the operability of the proton exchange membrane. Under the action of water or alcohol solution, the acid resin is easy to swell, and the volume becomes larger during the coating process, resulting in more defects. The polybenzimidazole film soaked in acid contains a large amount of phosphoric acid, and the catalyst cannot be coated on the film.

The main advantage of the GDE process is that the coating of the substrate is easy to operate, and the volume will not change during the coating process, so the quality of the formed catalytic layer is high. The main problem is that the interface between the proton exchange membrane and the catalytic layer depends on the post-hot pressing Manipulating builds, resulting in poorer performance and stability

At present, the modification of the existing technology mainly focuses on these two processes, and cannot take into account the two aspects of performance, production efficiency and quality.