Effect of operating temperature on fuel cell polarization curve

A similar effect may be expected if pure oxygen is used instead of air. Because oxygen concentration in air is only 21 %, operation with pure oxygen results in a 

The fuel cell efficiency is defined as a ratio between the electricity produced and hydrogen consumed. Of course, both must be in same units, such as Watts or kilowatts. 

Electricity produced is simply a product between voltage and current. 

It should be noted that AH/2F has dimension of Volts, and for AH = 286 kJ/mol it has a value of 1.482 V, which is the so-called thermo neutral potential. 

By combining Equations (III.38) through (III.41), the fuel cell efficiency is simply directly proportional to cell potential  

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Figure IIL7. Effect of operating temperature on fuel cell polarization curve [13],... 

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