Evaluation of tetrafluoroethane-1,2-disulfonic acid as a fuel cell electrolyte
Fuel cell cathode polarization in 70 w/o tetrafluoroethane-1,2-disulfonic acid (TFEDSA) was compared with that observed in trifluoromethane sulfonic acid (TFMSA) and phosphoric acid electrolytes. The type of electrode used was a wet-proofed Stackpole carbon paper substrate with the catalyst layer applied by direct filtration. The catalyst was 10 w/o Pt on Vulcan XC-72R carbon black supplied by Prototech and used as received. The polytetrafluoroethylene (PTFE) content and the curing conditions for the cathodes were optimized for each electrolyte by trial and error. The resulting polarization curves were infrarad corrected and show that all three electrolytes have about the same conductivity under the conditions used. The polarization behavior in TFEDSA was intermediate between that for 85 w/o phosphoric acid and that for 60 w/o TFMSA. More quantitative kinetic measurements in concentrated TFEDSA and also TFMSA were attempted using the rotating disc method but electrolyte impurity problems prevented definite determinations. The polarization results and the conductivity data indicate that it should be possible to operate a reformed methanol (0.1% CO) fuel cell using 70% TFEDSA at 110 degrees C and achieve a potential of 0.64V per cell on air at 200 mA/cm/sup 2/ with 0.75 mg Pt/cm/sup 2/ of catalyst. An impurity in TFMSA appears to be the source of sulfur produced at a hydrogen electrode in unpurified acid; the impurity is probably SO/sub 3/. Early samples of TFESDA were badly contaminated with sulfur oxides but improvement in synthesis eliminated these impurities. Purified forms of TFMSA and TFEDSA showed no chemical instability in the fuel cell tests in this laboratory.
- Research Organization:
- Lawrence Berkeley Lab., Materials and Molecular Research Division, Berkeley, CA
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 5442048
- Journal Information:
- J. Electrochem. Soc.; (United States), Vol. 130:4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Oxygen reduction in fuel cell electrolytes
Oxygen reduction in tetrafluoroethane-1,2-disulfonic acid
Related Subjects
ELECTRODES
PLATINUM
POLARIZATION
ELECTROLYTES
ORGANIC FLUORINE COMPOUNDS
SULFONIC ACIDS
FUEL CELLS
POLYTETRAFLUOROETHYLENE
WETTABILITY
DIRECT ENERGY CONVERTERS
ELECTROCHEMICAL CELLS
ELEMENTS
FLUORINATED ALIPHATIC HYDROCARBONS
HALOGENATED ALIPHATIC HYDROCARBONS
METALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
ORGANIC SULFUR COMPOUNDS
PLATINUM METALS
POLYETHYLENES
POLYMERS
POLYOLEFINS
TRANSITION ELEMENTS
300500* - Fuel Cells