Localized deactivation of a membrane
AssigneeGM Global Technology Operations LLC
InventorsMatthew M. Fay, Bebe T. Dobulis, Timothy J. Fuller
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Abstract
A method including providing an ion conductive membrane and deactivating a selected region of the membrane.
Claims19
A method comprising:
- providing an ion conductive membrane comprising a polymer electrolyte and having a body;
- deactivating an edge region by introducing at least one metal ion that forms insoluble sulfate and sultanate salts to said membrane extending through the thickness of the body and extending into the body thereof so that the edge region is not ion conductive, wherein the membrane includes a central active region which is ion conducting through the active region of the membrane, and said deactivated edge region which is not ion conducting surrounds the active region and prevents the conduction of ions through the deactivated region of the membrane.
A method as set forth in claim wherein said membrane comprises a proton conductive polymer electrolyte membrane.
A membrane for a membrane electrode assembly of a fuel cell, comprising a polymer electrolyte including sulfonic acid groups, said membrane having an ion conductive active central region and an ion non-conductive deactivated edge region, wherein said edge region comprises metal ions that form low solubility products with said sulfonic acid group of said polymer electrolyte to effectively render the edge region ion non-conductive.
A method comprising:
- providing an ion conductive membrane having a body and at least one edge region;
- said membrane comprising a polymer electrolyte including sulfonic acid groups;
- providing a membrane deactivating solution comprising at least one metal ion that forms a lower solubility product with sulfonic acid groups;
- immersing at least one edge region of the membrane in the deactivating solution to allow the metal on to form a low solubility product with the sulfonic acid groups of the polymer electrolyte and to render the at least one edge region ion non-conductive;
- removing the at least one edge region of the membrane from the deactivating solution;
- and
- removing any excess deactivating solution that may be left on the at least one edge region of the membrane;
- wherein the metal ion comprises at least one of barium, strontium, lead, silver or mercury ion.
A method comprising:
- providing an ion conductive membrane baying a body;
- deactivating a selected region of said membrane extending at least into the body thereof so that the selected region is not ion conductive, the deactivating comprising providing a deactivating solution and immersing said selected region of said membrane in said deactivating solution, wherein the solution comprising a metal ion that forms an insoluble sulfate and sulfonate salt and the metal ion comprises at least one of barium, strontium, lead, silver or mercury ion.
Dependencies are inferred from the claim text.