Self-supporting electrode with integral gas feed conduit

Claim 2

An elongated electrode, characterized in that said electrode comprises an electronically conductive self-supporting structure having an inner and outer wall and having an open end and a closed end, where the inner wall defines a conduit through the length of the electrode structure, where the area between the walls contains at least one additional conduit through the length of the electrode structure, and where the conduits communicate with each other near the closed end of the structure.

Claim 3

An electrode according to claim 1, charac­terized in that the composition of the structure is more dense near the inner wall.

Claim 4

An electrode according to claim 1, charac­terized in that the conduit defined by the inner wall is central to the electrode cross-section and there are at least four conduits surrounding the central conduit in the area between the walls.

Claim 5

An electrode according to claim 1, charac­terized in that a portion of the electrode structure containing the inner wall extends outward along the axial length of the electrode.

Claim 6

An electrode according to claim 1, charac­terized in that a portion of the outer wall of the elec­trode has openings therein connecting to conduits disposed in the area between the inner and outer walls.

Claim 7

An electrode according to claim 1, charac­terized in that the electrode comprises a material of LaMnO₃, CaMnO₃, LaNiO₃, LaCoO₃, LaCrO₃, or mixtures thereof.

Claim 8

An electrode according to claim 1, charac­terized in that the electrode consists essentially of LaMnO₃ doped with Sr.

Claim 9

An electrode according to claim 1, charac­terized in that the electrode has a contacting layer of solid electrolyte on the outer wall of the self-supporting electrode and an outer layer of porous electrode on top of the electrolyte, where the outer electrode and the electro­lyte have a discontinuity containing an electronically conductive interconnect which extends an axial length along the self-supporting inner electrode.

Claim 10

A plurality of the electrodes according to claim 8, where the inner self-supporting electrode is an air electrode, the outer electrode is a fuel electrode, the interconnect on one electrode structure is electronically connected to a fuel electrode of an adjacent electrode structure, fuel is fed to contact the fuel electrodes, and oxidant is fed to contact the air electrodes, where the air enters the conduit defined by the inner wall of the air electrode, flows to closed end of the air electrode and through a passage into the conduit in the area between the air electrode inner and outer walls, and then flows countercurrent to the entering air through the air electrode.

Claim 11

The plurality of electrodes according to claim 9 where the electrolyte is yttria stabilized zirco­nia and the fuel electrode is nickel zirconia cermet or cobalt zirconia cermet.