Direct Carbon Fuel Cell

A direct carbon fuel cell is a cell that relies on a carbon based material as a fuel. Unlike other forms of producing energy, a carbon based fuel cell produces energy by mixing oxygen with some form of rich carbon which results in the creation of energy. The byproduct of the reaction that takes place in a direct carbon fuel cell is carbon dioxide. The reason direct carbon fuel cells are becoming the preferred method of energy creation is because it has an efficiency of 70%. While it is not perfect, conventional combustion reactions only have an efficiency of about 35%.

To understand the chemistry of the reaction taking place, observe the following equation broken up into half cell notation:

Anode: C + 2 O(-2) –> CO2 + 4 e(-)

Cathode: O2 + 4 e(-) –> 2 O(-2)

Is it Environmentally Friendly?

Some would argue that it is not an environmentally friendly form of producing energy because the byproduct is carbon dioxide. However, because the efficiency of the direct carbon fuel cell is so much higher than the conventional combustion reaction, it requires a decreased amount of carbon based products. Because carbon dioxde requires one part carbon and two parts oxygen, if less carbon is being used to create the energy, less carbon dioxide is going to be relased which, in turn, results in a safer environment.

The best types of carbon for a direct carbon fuel cell are materials very rich in carbon. For example, coal, coke and char are three incredibly useful materials that can provide a considerable amount of carbon for the reaction to take place. Because it isn't releasing as much byproduct due to not needing it, the cell becomes very friendly to the environment.

Types of Direct Carbon Fuel Cells

There are currently four types of direct carbon fuel cells. Each has its own concept and system; however, they all are relatively beneficial and effective. They are:

• A more primitive form of direct carbon fuel cells, the first one is based on a solid oxide fuel cell concept in which the fuel (carbon) and oxidizes it to get the electrons from it and therefore, create energy.
• William W. Jacques obtained a US Patent for the molten hydroxides fuel cell in 1896. This is the second concept that had success in producing energy.
• In 1897, William W. Jacques obtained a Canadian patent for a Molten Carbonate Fuel Cell where the cell operates at extraordinarily high temperatures which creates the energy.
• A molten tin anode solid oxide fuel cell design. This uses molten tin as well as tin oxide.

All are successful varients of direct carbon fuel cells. With people more concerned about global warming and having a negative impact on the environment, more people have been looking to direct carbon fuel cells as a method in which they can create energy.