Improved Nickel Anodes for Industrial Water Electrolyzers

A method of increasing the energy efficiency of hydrogen production by alkaline water electrolysis is described. An ac activation of sintered Ni anodes leads to reductions in the oxygen evolution overpotential of ∼230 mV at 100–250 mA/cm 2 . The resulting reduction in cell voltage yields an increased energy efficiency and a significantly lowered cost of hydrogen production. Compared with other processes to raise anode efficiency, ac activation provides a fourfold improvement.