Claims
- 1. A process for producing a phosphoric acid-type fuel cell comprising a step of interposing a phosphoric acid electrolyte-retaining matrix between a pair of gas-diffusion electrodes, the electrolyte-retaining matrix being prepared by a method comprising the following steps:
- (1) preparing a mixture consisting essentially of silicon carbide powder and a metal phosphate-forming inorganic material, said silicon carbide powder having an average particle size of 0.1 to 10 .mu.m;
- (2) adding phosphoric acid in an amount larger than that required for forming a phosphate by the reaction with the inorganic material to the mixture; and
- (3) heating the phosphoric acid-containing mixture to a temperature of 100.degree.-250.degree. C. to form the metal phosphate as a binder bonding the silicon carbide together and to form a matrix retaining phosphoric acid as electrolyte therein; said matrix consisting essentially of 30-90 weight % of silicon carbide powder and 10-70 weight % of the metal phosphate.
- 2. A process according to claim 1 wherein the phosphoric acid is added to the mixture in such an amount that 40-80 wt. %, based on the silicon carbide powder, of phosphoric acid is present in free form other than phosphate.
- 3. A process for producing a phosphoric acid-type fuel cell according to claim 1 wherein the inorganic material is a metal oxide.
- 4. A process for producing a phosphate-type fuel cell according to claim 1 wherein the inorganic material is a metal salt.
- 5. A process for producing a phosphoric acid-type fuel cell according to claim 3 wherein the metal oxide is zirconium oxide.
- 6. A process for producing a phosphoric acid-type fuel cell according to claim 4 characterized in that the metal salt is zirconium chloride.
- 7. A process for producing a fuel cell according to claim 1, wherein a mixture of said silicon carbide with a metal salt solution is prepared.
- 8. A process for producing a fuel cell according to claim 3 wherein the metal oxide is tin oxide.
- 9. A process for producing a fuel cell according to claim 3 wherein the metal oxide is titanium oxide.
- 10. A process for producing a fuel cell according to claim 3 wherein the metal oxide is silicon oxide.
- 11. A process for producing a fuel cell according to claim 3 wherein the metal oxide is aluminum oxide.
- 12. A process for producing a fuel cell according to claim 4, wherein the metal salt is selected from the group consisting of a halide, a hydroxide, an oxychloride and a nitrate of at least one element selected from the group consisting of Zr, Ti, Sn, Si and Al.
- 13. A process for producing a fuel cell according to claim 1, wherein the inorganic material is a metal selected from the group consisting of Zr, Ti, Sn, Si and a mixture thereof.
- 14. A process for producing a fuel cell comprising a step of interposing an electrolyte-retaining matrix between a pair of gas-diffusion electrodes, wherein the electrolyte-retaining matrix is prepared by a method comprising the following steps:
- (1) preparing a mixture consisting essentially of silicon carbide powder and a metal phosphate-forming inorganic material, said silicon carbide powder having an average particle size of 0.1 to 10 .mu.m;
- (2) adding phosphoric acid in an amount required for forming a phosphate by the reaction with the inorganic material to the mixture; and
- (3) heating the phosphoric acid containing mixture to a temperature of 100.degree.-250.degree. C. to form the metal phosphate as a binder bonding the silicon carbide powder together and to form a matrix retaining phosphoric acid as electrolyte therein; said matrix consisting essentially of 30-90 weight % of silicon carbide powder and 10-70 weight % of the metal phosphate.
- 15. A process for producing a fuel cell according to claim 14 wherein the electrolyte to be retained by the matrix is phosphoric acid.
- 16. A process for producing a fuel cell according to claim 14 wherein the inorganic substance is zirconium oxide.
- 17. A process for producing a fuel cell according to claim 14 wherein a mixture of said silicon carbide with a metal salt solution is prepared.
Priority Claims (2)
Number |
Date |
Country |
Kind |
56-141525 |
Sep 1981 |
JPX |
|
56-141524 |
Sep 1981 |
JPX |
|
Parent Case Info
This is a division of application Ser. No. 414,394, filed Sept. 2, 1982, now U.S. Pat. No. 4,529,671.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
3453149 |
Adlhart et al. |
Jul 1969 |
|
3575718 |
Adlhart et al. |
Apr 1971 |
|
3594253 |
Froberg et al. |
Jul 1971 |
|
4017664 |
Breault |
Apr 1977 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
56-18366 |
Feb 1981 |
JPX |
332660 |
Jul 1930 |
GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
414394 |
Sep 1982 |
|