Membrane electrode assembly for a fuel cell
View Patent ↗A membrane electrode assembly for a fuel cell having a polymer electrolyte membrane, having a layer sequence comprising an ion-conducting membrane ( 2 ), a catalyst layer ( 3 ) and a gas diffusion layer ( 5 ). A substantially catalyst-free, porous condensation layer ( 5 ) is arranged between the catalyst layer ( 3 ) and the membrane ( 2 ).
1. A membrane electrode assembly for a fuel cell having a polymer electrolyte membrane, comprising:
a layer sequence having an ion-conducting membrane, a catalyst layer, a gas diffusion layer, and a substantially catalyst-free, porous condensation layer between the catalyst layer and the membrane, wherein the condensation layer is hydrophilic.
2. The membrane electrode assembly as recited in claim 1 wherein the condensation layer is ion-conducting at least in some regions.
3. The membrane electrode assembly as recited in claim 1 wherein the condensation layer has pores, the pores being provided on their inner surfaces with a coating of an ion-conducting material.
4. The membrane electrode assembly as recited in claim 3 wherein the coating includes a perfluorosulphonic acid polymer.
5. The membrane electrode assembly as recited in claim 3 wherein the coating includes an ion-conducting material corresponding to a membrane ion-conducting material of the membrane.
6. The membrane electrode assembly as recited in claim 3 wherein the coating includes methylcellulose.
7. The membrane electrode assembly as recited in claim 1 wherein the condensation layer has a smaller mean pore diameter than the catalyst layer.
8. The membrane electrode assembly as recited in claim 1 wherein the condensation layer has a mean pore diameter sufficient for capillary condensation.
9. The membrane electrode assembly as recited in claim 1 wherein the condensation layer is more hydrophilic than the catalyst layer.
10. The membrane electrode assembly as recited in claim 1 wherein the gas diffusion layer is hydrophobic.