Fuel Cells (SOFC, MCFC, PAFC, DMFC)

Question 1

What is an SOFC?

Answer 1

A solid oxide fuel cell (SOFC) is an electrochemical cell producing electricity directly from oxidizing fuel.

Question 2

What are the properties of a SOFC?

Answer 2

1. Operates at high T: 800 - 1000.
   - Therefore used for stationary applications.
2. No platinum catalysts required.
3. Conversion of fuel to electricity.
4. High efficiency if secondary electricity generation systems used.
5. Low densities in range of 0.1 - 1 kW/L.

Question 3

What are four advantages of SOFC?

Answer 3

1. Long-term stability.
2. Fuel flexibility.
3. Low emissions.
4. Low cost.
5. Uses less pure hydrogen, carbon monoxide, ammonia, methane and other liquid fuels.

Question 4

How does a SOFC operate?

Answer 4

1. Air insterted from cathode.
   Cathode: Air electrode
   - 0.5O2 + 2e- = O2-
2. Hydrocarbon fuel inserted from anode.
   Anode: Fuel electrode
   - H2 + O2- = H2O + 2e-
   - CO + O2- = CO2 + 2e-