PEM Fuel Cell

Safety Procedures

Please be aware of any potential hazard prior to operating any experiments. Only use deionized water when using the electrolyzer to produce the necessary hydrogen, H2, and oxygen, O2, for the PEM fuel cell. An electrical potential will be generated and measured, therefore, ensure all wire connections are secure. When using the methanol cell, use the 1%, 2%, or 3% concentration solutions provided to you. Even though it is a small concentration, it is still considered a flammable solution and any waste needs to be collected and disposed of properly. Ask a TA or staff to assist you with disposal.

Other Safety Concerns:

• Wear a lab coat and safety glasses at all times.

• Use switch to turn off electrolyzer.

• Use paper towels to dry any water spills.

Programs, Equipment, and Instruments

• Two digital multi-meters

• Double membrane fuel cell

• Single membrane fuel cell

• Methanol fuel cell

• Transfer pipettes

• Electrolyzer with hydrogen and oxygen fuel tanks

Objectives

1. Use nonlinear regression to determine the coefficients of the polarization (sometimes called "characteristic") curve given as Eq. (5) in Kim, Lee, et al.

2. Create a power performance curve as described by Fig 4 Benziger et al, 2006. Include both axes if possible.

3. Compare the behavior of the above two curves for pure O2 versus air.

Tips

1. The flow of electrons should be from the positive (red) fuel cell terminal, through the decade resistance box, through the current meter (ammeter), and back to the negative (black) fuel cell terminal. The voltage meter (voltmeter) should be connected to the positive and negative fuel cell terminals.

2. Before using the fuel cell, purge the gas feed lines:

   1. Close all valves.

   2. Run the electrolyzer until the H2 and O2 storage tanks are full.

   3. Open all valves to let the gas flow through the lines, through the fuel cell, and exit to the atmosphere.

   4. Repeat these three steps two more times.

3. If the confidence intervals of your characteristic curve include zero, then that region most likely does not exist in your data (you'll need to explain why). Repeat the fit without those parameters until you obtain satisfactory coefficients.

References

1. Larmine, J.; Dicks, A. Fuel Cell Systems Explained, 2nd Ed., John Wiley & Sons: West Sussex, 2003.

2. Kim, J.; Lee, S.; Srinivasan, S.; Chamberlin, C.E. J. Electrochem. Soc., 1995, 142, 2670-2674.

3. Benziger, J.B.; Satterfield, M.B.; Hogarth, W.H.J.; Nehlsen, J.P.; Kevrekidis, I.G. J. Power Sources, 2006, 155, 272-285.

4. Hoogers, G. Fuel Cell Technology Handbook. CRC Press: Boca Raton, 2003.

5. Chalk, S.G.; Miller, J.F. J. Power Sources, 2006, 159, 73-80

6. Fuel Cells 2000. http://fuelcells.org/ (accessed April 14, 2015)

7. Logan et. al., Microbial Fuel Cells: Methodology and Technology, Environ. Sci. Technol., 2006, 40, 5181-5192 [web link]

8. Rabaey, K.; Clauwert, P.; Aelterman, P.; Verstraete, W. Tubular microbial fuel cells for efficient electricity generation. Environ. Sci. Technol. 2005, 39, 8077-8082.