Chapter 6. Alkaline Anionic Exchange Membrane Water Electrolysers

Alkaline anion exchange membrane water electrolysers (AAEMWE) use electrical energy to split water into its elemental components, hydrogen (on the cathode) and oxygen (on the anode). The cell reactions in the AAEMWE are the same as in traditional alkaline electrolysers using 30–35 wt% KOH liquid electrolyte. The essential difference between AAEMWE and Alkaline Water Electrolysis (AWE) is that the liquid electrolyte is replaced by a thin ion exchange membrane (solid electrolyte) to allow for OH− anions transport. This chapter describes the state of the art of AAEMWEs. It discusses aspects of electrocatalysts for the cell reaction and the membrane technology required for cell fabrication. A discussion of cell and stack construction materials is provided. Performance data for recently developed hydrogen generation cells is also provided with current progress towards commercial systems described.