A high-rate and high-efficiency molten-salt sodium–oxygen battery

A molten-salt Na–O 2 battery featuring a liquid Na negative electrode and Ni positive electrode was found to form Na 2 O 2 on discharge, enabled by nitrate redox where NO 3 − is reduced to Na 2 O and NO 2 − , then reactions with O 2 produce Na 2 O 2 and reform NO 3 − .