Abstract

Engineers, scientists and environmentalists have been working on the development of clean energy technology. Now-a-days widely available clean energy sources are solar panels and wind mills. The problem associated with them is the stability of the source since solar energy and wind energy cannot be available in night time and cloudy days, and windless days, respectively. Therefore, researchers are always in search of another energy source. In 1962, Scientists at Westinghouse Electric Corporation first announced that electricity can be successfully generated using solid electrolyte. The new device using this solid electrolyte is known as solid oxide fuel cell (SOFC).

SOFC is a solid electrochemical conversion device which directly converts chemical energy of fuel into electrical energy. In this device, fuel is oxidized with the help of oxygen; air is used as the source of oxygen. The advantage of this fuel cell is that it does not contain liquid electrolyte, so there is no chance of liquid flooding. The primary structure of unit cell consists of anode, cathode and electrolyte; interconnect is necessary for assembling many cells together and sealant is another optional component for planner type of SOFC to prevent mixing of fuel and air.Electrolyte is nonporous to avoid mixing of fuel and air directly while the electrodes are porous to allow fuel and air to come in contact with triple phase boundary (TPB) where reaction takes place between fuel gas and oxidant in presence of electrode and electrolyte; electrolyte must be ion conducting along with electronically non-conducting while the electrodes must be both ionic and electronically conductive to facilitate current collection (in cathode) and catalytic activities.