What is the maximum theoretical energy efficiency of a fuel cell?
What is the maximum theoretical energy efficiency of a fuel cell? Correct Answer 83%
E°cell of an H2-O2 fuel cell = 1.23 V and ΔH=-285.8 kJ mol-1 ΔG = -n x F x E°cell = -2 x 96500 x 1.23 = -237390 J mol-1 = -237.390 kJ mol-1 Efficiency = ΔG/ΔH x 100 = -237.390/-285.8 x 100 = 83%.