Protonic Ceramic Fuel Cells (PCFC)

Protonic Ceramic Fuel Cells are similar to SOFCs in many ways. The major difference is that hydrogen moves through the ceramic electrolyte rather than oxygen. These fuel cells are much like a hybrid between a SOFC and a PEMFC.

Function and Reactions of PCFCs

These function much like direct PEMFCs. A hydrocarbon fuel is injected at the anode where, in the presence of water, it is broken down into protons, electrons, and carbon dioxide. The protons are able to move through the ceramic layer to the cathode, while electrons must take an external route. The ceramic within PCFCs is highly conductive to protons at elevated temperatures, acting much like the polymer membrane in a PEMFC.

Benefits of PCFCs

The major benefit of PCFCs is their ability to utilize a wide variety of fuel sources. Coal, wood, hydrocarbons, and even non-fossilized organic matter can all be used as fuel.

Running at high temperatures has the additional advantage of increasing the efficiency of these fuel cells when their excess heat is coupled to the production of energy. Currently, efficiency hovers around 60% without coupling and 70% with coupling.

Drawbacks and Future Research of PCFCs

The largest drawback to PCFCs is that their high temperatures require long startup times. The other drawback is their size. They are often the size of a refrigerator. There is current research aimed at creating high density PCFCs for mobile usage.