(N/A) fuel cell is a device that converts chemical energy directly into electrical energy and possesses a construction similar to a galvanic cell.
Construction: In fuel cells,reactants are fed continuously to the electrodes,and products are removed continuously from the electrolyte compartment. These cells are designed to convert the energy of combustion of fuels like $H_2$,$CH_4$,or $CH_3OH$ directly into electrical energy.
Advantages of fuel cells:
$(i)$ There is no air or noise pollution.
$(ii)$ Fuel cells have high efficiency of $70 \%$ or more,whereas thermal power stations have low efficiency of $40 \%$ or less.
$(iii)$ Various types of fuels can be used in fuel cells.