Question

The theoretical voltage of a fuel cell is 1.23 V.

If the operating point of the fuel cell is 0.6 V, the overpotential losses are______V.​

Answer 1

Answer:

0.246 V

Explanation:

The theoretical voltage of a fuel cell is 1.23 V and the operating voltage of the cell is 0.6 V and the value drops even more once the current starts to flow.

The reasons are;

1) The over-potential is required to make the cathode reaction proceed at a fast enough rate.

O₂ + 4e⁻ + 4H⁺ → 2H₂O

2) Charge carriers lose energy in the form of heat when the current flows through the media.

Hence the over-potential losses is around 20% of the total voltage, which is 1/5 of 1.23 which is 0.246 V