Solid oxide fuel cell
View Patent ↗A solid oxide fuel cell ( 10 ) comprises an anode electrode ( 12 ), a cathode electrode ( 14 ) and an electrolyte ( 16 ) between the anode electrode ( 12 ) and the cathode electrode ( 14 ). A gaseous fuel is supplied to an anode chamber ( 18 ) partially defined by the anode electrode ( 12 ) and a gaseous oxidant is supplied to a cathode chamber ( 20 ) partially defined by the cathode electrode ( 14 ). The electrolyte ( 16 ) comprises a first dense non-porous layer ( 22 ), a second porous layer ( 24 ) on the first dense non-porous layer ( 22 ) and a third dense non-porous layer ( 26 ) on the second porous layer ( 24 ). The anode electrode ( 12 ) is arranged on the first dense non-porous layer ( 22 ) and the cathode electrode ( 14 ) is arranged on the third dense non-porous layer ( 26 ). The second porous layer ( 24 ) acts as a buffer between the first dense non-porous layer ( 22 ) and the third dense non-porous layer ( 26 ) to prevent defects propagating between the layers ( 22,26 ) and to prevent fuel and oxidant leaking through the electrolyte ( 16 ).
1. A solid oxide fuel cell comprising an anode electrode, a cathode electrode and an electrolyte between the anode electrode and the cathode electrode, characterized in that the electrolyte comprises a first dense non-porous layer, a second porous layer on the first dense non-porous layer and a third dense non-porous layer on the second porous layer.
2. A solid oxide fuel cell as claimed in claim 1 comprising a porous layer between the electrolyte and the anode electrode.
3. A solid oxide fuel cell as claimed in claim 2 comprising a porous layer between the electrolyte and the cathode electrode.
4. A solid oxide fuel cell as claimed in claim 1 comprising a porous layer between the electrolyte and the cathode electrode.
5. A solid oxide fuel cell as claimed in claim 1 wherein the first, second and third layers of the electrolyte have the same composition.
6. A solid oxide fuel cell as claimed in claim 1 wherein at least one of the layers of the electrolyte comprises gadolinia-doped ceria.
7. A solid oxide fuel cell as claimed in claim 6 wherein all the layers of the electrolyte comprise gadolinia-doped ceria.
8. A solid oxide fuel cell as claimed in claim 1 wherein at least one of the layers of the electrolyte comprises scandia-doped zirconia.
9. A solid oxide fuel cell as claimed in claim 8 wherein all the layers of the electrolyte comprise scandia-doped zirconia.
10. A solid oxide fuel cell stack comprising a plurality of solid oxide fuel cells as claimed in claim 1 .
11. A solid oxide fuel cell stack comprising a plurality of solid oxide fuel cells, each solid oxide fuel cell comprising an anode electrode, a cathode electrode and an electrolyte between the anode electrode and the cathode electrode, each electrolyte comprising a first dense non-porous layer, a second porous layer on the first dense non-porous layer and a third dense non-porous layer on the second porous layer.
12. A solid oxide fuel cell comprising an anode electrode, a cathode electrode and an electrolyte between the anode electrode and the cathode electrode, characterized in that the electrolyte comprising a first dense non-porous layer, a second porous layer on the first dense non-porous layer and a third dense non-porous layer on the second porous layer wherein the first, second and third layers of the electrolyte have the same composition.
13. A solid oxide fuel cell comprising an anode electrode, a cathode electrode and an electrolyte between the anode electrode and the cathode electrode, characterized in that the electrolyte comprises a first dense non-porous layer, a second porous layer on the first dense non-porous layer and a third dense non-porous layer on the second porous layer wherein the electrolyte comprises a fourth porous layer on the third dense non-porous layer and a fifth dense non-porous layer on the fourth porous layer.