Got Enough O?

Dominik C.
6th Grade, Suntree Elementary, Melbourne, Florida
Teacher: Pam Seaton

Dominik's Science Fair Project board
Click to view a close-up

Question: Is there a difference if air instead of pure oxygen is used in a fuel cell?

Hypothesis: I believe there is a difference because of the reduced oxygen supply; indeed, the air only contains 21% oxygen (78% nitrogen, 1% argon and other gases)

Conclusion: My hypothesis was correct. There is a difference in the characteristic curve of a hydrogen fuel cell when using air instead of oxygen. This experiment showed that the current rises quickly as the resistance is increased, which puts a greater demand for electricity on the fuel cell. Using air resulted in a dip in the characteristic curve at higher currents as a result of the reduced oxygen supply. The air which provides less oxygen resulted in the fuel cell not being able to produce enough electricity for the demand because of this reduced oxygen supply.