Alcohol and Borohydride Alkaline Fuel Cells

Direct Alcohol and Borohydride Alkaline Fuel Cells... 

Fig. 14 (a) Schematic diagram of direct alcohol or borohydride alkaline fuel cell. 1. Fuel-electrolyte mixture storage 2. Exhausted-fuel-electrolyte mixture storage 3, 4. Peristaltic pump 5. Load 6. Anode terminal 7. Cathode terminal 8. Air 9. Cathode electrode 10. Anode electrode 11. Fuel and electrolyte mixture 12. Magnetic stirrer 13. Anode shield, (b) Experimental set-up for direct alchol or sodium borohydride alkaline fuel cell. 

The lifetime test of direct alcohol and sodium borohydride alkaline fuel cell was conducted and the results pertaining to this is shown in Fig. 30. The useful operating lifetime of 380, 400, 510 h was found for methanol, ethanol and sodium borohydride fuels, respectively. The deterioration of performance of fuel cell may be because of the carbonate precipitate, oxide layer formation and adsorbed intermediate species on catalyst surface. The used up electrodes could be regenerated by treating the electrode with hydrochloric acid. The acid treatment might have removed the carbonates and other species from the electrode. The treated electrodes could regain more than 80% of the catalytic activity. The maximum power density with 2 M fuel and 3 M KOH obtained was 21.5 mW cm at 33 mA cm of current density for sodium borohydride at 60°C, whereas, methanol and ethanol produce 15 and 16 mW cm" of maximum power... 

Verma, A. and Basu, S. Direct use of alcohols and sodium borohydride as fuel in an alkaline fuel cell , J. Power Sources, 145 (2005b) 282-285. 

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