Claims
- 1. A process for the production of thin carbon plates useful in primary and secondary electrochemical cells and having a thickness from 0.25 mm to 5 mm and a porosity of 30% to 85% by volume comprising: (1) impregnating a cellulose sheet material consisting essentially of cotton linters with a carbonaceous impregnant selected from the group consisting of coal tar, solvent-cut coal tar pitch, slurry oil, creosote oil and mixtures thereof, (2) curing said impregnated material in air at a temperature from 90.degree. to 300.degree. C., and (3) baking said material in an inert or reducing atmosphere to carbonize the impregnant.
- 2. The process of claim 1 wherein the steps of impregnating, curing and baking are repeated until a desired porosity is reached.
- 3. The process of claim 1 wherein the impregnated material is cured in air for about 24 hours at about 225.degree. C.
- 4. The process of claim 1 wherein the impregnated material is cured and then baked on a heating schedule rising from ambient to about 600.degree. C. in about 8 hours.
- 5. The process of claim 1 for the production of carbon plates useful as electrodes in zinc-halogen batteries, wherein the impregnated material is cured, baked, and then graphitized in nitrogen on a schedule rising to a temperature in the range of from about 1900.degree. to about 3200.degree. C.
- 6. The process of claim 4 wherein the baked material is re-impregnated and re-baked on a heating schedule rising from ambient to about 600.degree. C. in about 8 hours.
- 7. The process of claim 1 wherein the material is baked in an inert or reducing atmosphere for 8 to 72 hours.
- 8. A process for producing a porous carbon plate for use in a fuel cell and having a thickness of from 0.25 to about 2.6 mm and a porosity by volume of 30 to 85% comprising: (1) impregnating a paper sheet consisting essentially of cotton linters with a carbonaceous liquid selected from the group consisting of coal tar, solvent-cut coal tar pitch, slurry oil, creosote oil and mixtures thereof, (2) curing said impregnated material in air at a temperature from 90.degree. to 300.degree. C., (3) baking said material in an inert or reducing atmosphere to carbonize the impregnant, and (4) repeating said impregnation, cure and bake cycles until a desired porosity is achieved.
- 9. The process of claim 8 wherein the impregnated material is cured in air at about 225.degree. C.
- 10. The process of claim 8 wherein the carbon plate is further heated to a graphitizing temperature in the range of 1900.degree. to 3200.degree. C.
- 11. The process of claim 10 wherein the graphitized material is re-impregnated, cured, baked, and graphitized until a selected porosity is achieved.
- 12. The process of claim 10 wherein the plate is heated to a graphitizing temperature of at least 2700.degree. C.
- 13. The process of claim 8 wherein the carbonaceous liquid is creosote oil.
- 14. The process of claim 8 wherein the product is an essentially flat plate.
- 15. The process of claim 8 wherein the product is a tubular cylinder.
- 16. The process of claim 8 wherein the carbonaceous liquid is a blend of 50% creosote oil and 50% coal tar.
Parent Case Info
This is a continuation of application Ser. No. 06/501,633, filed June 6, 1983, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
005687 |
Dec 1974 |
JPX |
2109006 |
Apr 1983 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
501633 |
Jun 1983 |
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