Stack structure for fuel cell
Provided is a stack structure for fuel cells. The stack structure includes a plurality of fuel cells stacked to generate electricity. The stack structure further includes an interconnector and a frame. The interconnector is divided into a central region supporting and electrically connected with the fuel cells and an edge region outwardly extending from an end of the fuel cell. The frame is disposed to support a side of the fuel cell in the edge region of the interconnector, and has a combined functional layer coated on an entire surface of the frame.
1. A fuel cell stack structure, comprising:
a fuel cell comprising an electrolyte layer, a cathode layer, and an anode layer on respective surfaces of the electrolyte layer;
a first interconnector disposed on the fuel cell, the first interconnector comprising a first central region overlapping with the cathode layer and a first edge region surrounding the first central region and outwardly extending from an end of the fuel cell;
a second interconnector disposed under the fuel cell, the second interconnector comprising a second central region overlapping with the anode layer of the fuel cell and a second edge region surrounding the second central region and outwardly extending from the end of the fuel cell; and
a frame comprising an opening exposing one of the cathode layer and the anode layer to be disposed between the first edge region of the first interconnector and the second edge region of the second interconnector, the frame supporting an edge region of the fuel cell and comprising an insulating combined functional layer coated on an entire surface thereof.
2. The structure according to claim 1 , wherein the combined functional layer comprises an insulating ceramic material.
3. The structure according to claim 2 , wherein the combined functional layer includes an oxide or a glass.
4. The structure according to claim 1 , further comprising:
a gap maintaining unit disposed between one of the first and second interconnectors and the combined functional layer of the frame to uniformly maintain a gap therebetween.
5. The structure according to claim 1 , further comprising:
a sealing unit disposed between one of the first and second interconnectors and the combined functional layer of the frame to seal a space therebetween, the sealing unit comprising an insulating ceramic material.
6. The structure according to claim 1 , wherein the frame is formed of a metal material including chromium (Cr).
7. The structure according to claim 1 , wherein the fuel cell includes a solid oxide fuel cell (SOFC).
8. The structure according to claim 4 , wherein the gap maintaining unit comprises an insulating ceramic material.
9. The structure according to claim 4 , further comprising a plurality of supporting units for supporting a side of the gap maintaining unit.
10. The structure according to claim 9 , wherein the supporting units protrude from any one of the frame, the first interconnector and the second interconnector.
11. The structure according to claim 4 , wherein the gap maintaining unit protrudes from any one of the frame, the first interconnector and the second interconnector.
12. The structure according to claim 1 , further comprising a current collector disposed between one of the first and second interconnectors and the cathode layer.