Production of membrane electrode assemblies and stacks thereof
In a method for the production of a membrane electrode assembly comprising a membrane, electrodes and a catalyst, the catalyst is pressed into the membrane material, e.g. when forming the material in situ.
1. A method for the production of a membrane electrode assembly (MEA), which comprises assembling the components thereof, including a membrane, electrodes and a catalyst, wherein the assembling also comprises:
depositing solid catalyst particles on the surface of a transfer medium;
introducing a monomer mixture into the space between two such catalyst-coated transfer media;
polymerizing the mixture in situ, whereby the catalyst is pressed into the membrane material, thereby forming the membrane in situ; and
peeling away the transfer media;
wherein the membrane is hydrophilic and hydratable.
2. The method according to claim 1 , wherein the catalyst is present on a surface of at least one of the electrodes.
3. The method according to claim 1 , wherein forming the membrane comprises expansion.
4. The method according to claim 1 , for the production of a stack of MEAs.
5. A method for the production of a membrane electrode assembly (MEA), which comprises assembling the components thereof, including a membrane, electrodes and a catalyst, wherein the assembling also comprises:
depositing solid catalyst particles on the surface of an electrode material;
treating the solid catalyst particles to render the catalyst active and permanently attached to the electrode material;
introducing a monomer mixture into the space between two such catalyst-coated electrode materials; and
polymerizing the mixture in situ, whereby the catalyst is pressed into the membrane material thereby forming the membrane in situ;
wherein the membrane is hydrophilic and hydratable.
6. The method according to claim 5 , wherein the catalyst is present on a surface of at least one of the electrodes.
7. The method according to claim 5 , wherein forming the membrane comprises expansion.
8. The method according to claim 5 , for the production of a stack of MEAs.
9. The method according to claim 5 , wherein the catalysed surface of the electrode material is pressed against the surface of a thermoplastic film at a temperature above the glass transition temperature of the film, so that the catalyst particles are partially impressed into the surface of the film.