Fuel cell film electrode and preparation method thereof

Abstract

The invention discloses a fuel cell film electrode and a preparation method thereof. The film electrode comprises a gas diffusion layer and catalysis layers, wherein, the catalysis layer is of multilayer composite structure and is mainly composed of a catalytic active metal, a water repellent and a conductive ion polymer, wherein, the conductive ion polymer has different contents among the catalysis layers; the multilayer composite structure has at least two layers, wherein, the first layer is a partial hydrophobic catalysis layer while the second layer is a hydrophilic catalysis layer. The invention further discloses a preparation method of the fuel cell film electrode, wherein, the diffusion layer is prepared by the dry method, the inventive film electrode structure has better water-gasmanagement ability, more uniform and stabler mass transfer and excellent electron and proton conducting ability, thus increasing the utilization rate of catalysts and enhancing electric output performance of the fuel cell.

Description

technical field [0001] The invention relates to a fuel cell, in particular to a fuel cell membrane electrode and a preparation method thereof. Background technique [0002] Fuel cells have the advantages of high energy conversion efficiency, easy start-up, and low environmental pollution. They are considered to be the best "clean energy" in the future, and many governments have invested heavily in their research. Especially proton exchange membrane fuel cells (PEMFCs), because it can be used as a power source for electric vehicles, a distributed power station and a portable mobile power source, has attracted widespread attention from all over the world in recent years, and its key technologies have also developed rapidly. . [0003] Three-in-one membrane electrode It is the core component of the proton exchange membrane fuel cell. Its performance is good or bad. The gas diffusion layer is usually composed of conductive porous materials. Its function is to collect current,...

AI Technical Summary

Problems solved by technology

The traditional hydrophobic electrode has a relatively thick catalytic layer, a large content of hydrophobic agent, and a relatively large internal resistance; and the ion-conducting polymer (Nafion) enters on the surface of the catalytic layer by spraying or immersing, so it is difficult to ensure its Fully penetrated into the catalytic layer and fully contacted with the catalyst particles, H + High conduction resistance

There is no hydrophobic agent in the catalytic layer of the thin-layer hydrophilic electrode, so there are fewer gas channels, and the gas transfer resistance is larger; and the catalyst is bonded with Nafion, and its bonding strength will gradually decrease during long-term work, thereby reducing the performance of the electrode.

The ultra-thin layer electrode is to prepare the catalyst on the electrode by sputtering deposition method, the conditions are relatively harsh, and it is not suitable for large-scale production

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