Recent progress, advances, and future prospects in Na–O2 batteries

An energy storage technology, that uses sustainable and abundant materials such as sodium and oxygen, known as Na-air/O2 battery (NAB), is desirable for our society and is a real alternative to current and dominant technologies such as Li-ion batteries. However, this technology (NAB) still requires more research to overcome some of the main issues that affect the battery components, electrodes, and electrolytes. Important breakthroughs have been published during the last decade to gain deep knowledge into the battery operation towards NAB commercialisation. In this opinion, we cover the most research in the charge and discharge mechanism, as well as the sudden death of NABs reported in the literature. The section on future directions will be a valuable guidance to the research society and the development of the NAB technology.