Low temperature ceramic fuel cells employing lithium compounds : A review

Ceramic fuel cells employing lithium compounds show very high ionic conductivity and remarkable power density at temperatures of 350–600 °C. A composite electrolyte made of ceramic powder and lithium compound can reach ionic conductivities >0.1 S cm⁻¹ at 550 °C, even up to 0.5 S cm⁻¹. This is more than 100-times higher than the electrolyte conductivity of traditional solid oxide fuel cells employing e.g. yttria stabilized zirconia, yttrium doped barium zirconate, or strontium and magnesium doped lanthanum gallate. A fuel cell with a lithium compound for symmetrical electrode and single-oxide or composite oxide as electrolyte can reach a power density above 1 W cm⁻². Here, the development and progress of the ceramic lithium compound composite electrolyte fuel cell is reviewed to better understand its working mechanism, the origins for the high ionic conductivity, and the excellent low-temperature catalytic activity of the electrode.