Cathode composition, cathode and fuel cell including same

1. An air electrode composition comprising:

an oxide particle represented by the following Chemical Formula 1 and having a perovskite-type (ABO 3 ) structure; and

an electrolyte material:

Bi x (M1) 1-x   [Chemical Formula 1]

wherein, in Chemical Formula 1,

0.2< x< 0.8;

M1 is one or more elements selected from the group consisting of barium (Ba), sodium (Na), potassium (K) and gadolinium (Gd);

E is one or more elements selected from the group consisting of magnesium (Mg), aluminum (Al), vanadium (V), gallium (Ga), germanium (Ge), niobium (Nb), molybdenum (Mo), indium (In), tin (Sn), hafnium (Hf), tantalum (Ta), tungsten (W), titanium (Ti), chromium (Cr), manganese (Mn), nickel (Ni), cobalt (Co), copper (Cu), zinc (Zn), holmium (Ho), erbium (Er), thulium (Tr), ytterbium (Yb) and iron (Fe); and

δ is a value making the oxide particle electrically neutral.

2. The air electrode composition of claim 1 , wherein M1 is barium (Ba).

3. The air electrode composition of claim 1 , wherein E is iron (Fe).

4. The air electrode composition of claim 1 , wherein Chemical Formula 1 is represented by Bi 0.5 Ba 0.5 FeO 3 .

5. The air electrode composition of claim 1 , wherein the electrolyte material includes one or more types selected from the group consisting of zirconia-based that is not doped or is doped with at least one of gadolinium, yttrium, scandium, calcium and magnesium; ceria-based that is not doped or is doped with at least one of gadolinium, samarium, lanthanum, ytterbium and neodymium; bismuth oxide-based that is not doped or is doped with at least one of calcium, strontium, barium, gadolinium and yttrium; and lanthanum gallate-based that is not doped or is doped with at least one of strontium and magnesium.

6. The air electrode composition of claim 1 , wherein the electrolyte material includes one or more types selected from the group consisting of gadolinium-doped ceria (GDC), gadolinium-doped zirconia (GDZ), samarium-doped ceria (SDC), samarium-doped zirconia (SDZ), yttrium-doped ceria (YDC), yttrium-doped zirconia (YDZ), yttria-stabilized zirconia (YSZ), scandia-stabilized zirconia (ScSZ), lanthanum strontium gallate magnesite (LSGM) and lanthanum-doped ceria (LDC).

7. The air electrode composition of claim 1 , wherein a content ratio of the oxide particle to the electrolyte material in the air electrode composition is in a range of 9:1 to 3:7.

8. The air electrode composition of claim 1 , further comprising at least one of a solvent, a dispersant, a binder and a plasticizer.

9. The air electrode composition of claim 1 , which has sheet resistance (ASR) of 2 Ωcm 2 or less under a temperature condition of 600° C. to 700° C.

10. The air electrode composition of claim 1 , wherein the oxide particle has a coefficient of thermal expansion in a range of 11×10 −6 /C to 13×10 −6 /C.

11. An air electrode formed with the air electrode composition of claim 1 .

12. An air electrode comprising the air electrode composition of claim 1 .

13. The air electrode of claim 11 , wherein a content ratio of the oxide particle to the electrolyte material in the air electrode is in a range of 9:1 to 3:7.

14. A fuel cell comprising:

the air electrode of claim 11 ;

a fuel electrode; and

an electrolyte provided between the air electrode and the fuel electrode.

15. A method for manufacturing a fuel cell comprising:

forming an air electrode by coating the air electrode composition of claim 1 on an electrolyte surface and then sintering the result; and

forming a fuel electrode on a surface opposite to the air electrode-formed surface of the electrolyte.

16. A cell module comprising the fuel cell of claim 14 as a unit cell.