Direct Carbon Fuel Cells
Direct carbon fuel cells (DCFCs) are high temperature fuel cells which offer the possibility to directly convert the chemical energy of carbon materials (e.g. coal, lignite, char, carbonized biomass) into electricity. In addition to using solid carbon fuels, higher overall efficiencies should be possible because the thermodynamic efficiency is close to 100 %. This means higher than those of conventional fuel cell types for gaseous fuels.
DCFC technology can employ three different electrolyte types: Molten carbonate electrolyte (liquid salt), molten hydroxide electrolyte (liquid salt) and solid oxide electrolyte (solid ceramic layer). Recently, also combined technologies have been developed.
In this chapter, all the concepts are described and their advantages and difficulties are discussed.