Molten salt-containing metal electrode for rechargeable oxide-ion battery cells operating below 800?c

A molten salt-containing electrode for a rechargeable oxide-ion battery cell operating below 800° C., comprising:

• a molten salt-containing electrode consisting essentially of α Active Metal-βActive Metal Oxide-Active Metal Y, where Active Metal Y is a salt, α+β+ε=1 and the Active Metal and Active Metal Oxide are soluble in the selected salt, when molten at from 500° C. to 800° C.