Solid polymer electrolyte composite membrane comprising porous ceramic support
View Patent ↗A solid polymer electrolyte composite membrane and method of manufacturing the same. The composite membrane comprises a porous ceramic support having a top surface and a bottom surface. The porous ceramic support may be formed by laser micromachining a ceramic sheet or may be formed by electrochemically oxidizing a sheet of the base metal. A solid polymer electrolyte fills the pores of the ceramic support and preferably also covers the top and bottom surfaces of the support. Application of the solid polymer electrolyte to the porous support may take place by applying a dispersion to the support followed by a drying off of the solvent, by hot extrusion of the solid polymer electrolyte (or by hot extrusion of a precursor of the solid polymer electrolyte followed by in-situ conversion of the precursor to the solid polymer electrolyte) or by in-situ polymerization of a corresponding monomer of the solid polymer electrolyte.
1. A solid polymer electrolyte composite membrane, said solid polymer electrolyte composite membrane comprising:
(a) a ceramic support, said ceramic support having opposing top and bottom surfaces and a plurality of pores extending from said top surface to said bottom surface;
(b) a first solid polymer electrolyte, said first solid polymer electrolyte completely filling all of said pores and covering said top and bottom surfaces of said ceramic support; and
(c) a second solid polymer electrolyte positioned at least one of over the top and under the bottom of said first solid polymer electrolyte, said second solid polymer electrolyte differing from said first solid polymer electrolyte.
2. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein each of said plurality of pores extends in a straight line perpendicularly from said top surface to said bottom surface.
3. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said plurality of pores are arranged in a non-random pattern.
4. The solid polymer electrolyte composite membrane as claimed in claim 3 wherein said plurality of pores are arranged in a hexangular pattern.
5. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said pores are unevenly distributed throughout said ceramic support.
6. The solid polymer electrolyte composite membrane as claimed in claim 5 wherein said ceramic support has a periphery and wherein said pores are positioned in a greater concentration distal to said periphery than proximate to said periphery.
7. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said pores are arranged in a honeycomb pattern.
8. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said pores are cylindrical in shape.
9. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said pores have a diameter of about 0.01 to 200 microns.
10. The solid polymer electrolyte composite membrane as claimed in claim 9 wherein said pores have a diameter of about 1 to 200 microns.
11. The solid polymer electrolyte composite membrane as claimed in claim 9 wherein said pores have a diameter of about 0.01 to 100 microns.
12. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said pores constitute about 20% to 95% of said ceramic support.
13. The solid polymer electrolyte composite membrane as claimed in claim 12 wherein said pores constitute about 40% to 70% of said ceramic support.
14. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said ceramic support comprises a material selected from the group consisting of silica, quartz, glass, boron carbonate, silicon carbide, alumina, titania, silica tungstate, sintered valve metal oxides and non-conductive diamond or diamond-like coatings.
15. The solid polymer electrolyte composite membrane as claimed in claim 14 wherein said ceramic support comprises a ceramic selected from the group consisting of silica, alumina and silicon carbide.
16. The solid polymer electrolyte composite membrane as claimed in claim 15 wherein said ceramic support is made of alumina.
17. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said ceramic support has a thickness of about 1 to 50 microns.
18. The solid polymer electrolyte composite membrane as claimed in claim 17 wherein said ceramic support has a thickness of about 7.5 to 15 microns.
19. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said first solid polymer electrolyte is selected from the group consisting of polymer compositions that contain metal salts, polymeric gels that contain electrolyte and ion exchange resins.
20. The solid polymer electrolyte composite membrane as claimed in claim 19 wherein said first solid polymer electrolyte is an ion exchange resin.
21. The solid polymer electrolyte composite membrane as claimed in claim 20 wherein said first solid polymer electrolyte is perfluorosulfonic acid (PFSA) polymer.
22. The solid polymer electrolyte composite membrane as claimed in claim 21 wherein said PFSA polymer has an equivalent weight of about 200 to 2000.
23. The solid polymer electrolyte composite membrane as claimed in claim 22 wherein said PFSA polymer has an equivalent weight of about 500 to 1200.
24. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said solid polymer electrolyte composite membrane has a thickness of about 5 to 300 microns.
25. The solid polymer electrolyte composite membrane as claimed in claim 24 wherein said solid polymer electrolyte composite membrane has a thickness of about 7.5 to 200 microns.
26. The solid polymer electrolyte composite membrane as claimed in claim 1 wherein said solid polymer electrolyte composite membrane has an ionic conductivity of 0.001 S/cm to 0.7 S/cm at room temperature with a relative humidity of 100%.