In pursuit of a carbon-neutral society, advancement of battery technology becomes imperative. Primary batteries, though nonrechargeable, hold promise as power sources for sensors and disaster scenarios because of their cost-effective production and voltage stability. However, most of these batteries employ expensive metal electrodes, such as lithium electrodes, necessitating exploration of alternative electrode materials.
Using carbon-based materials for the cathode, magnesium (Mg) for the anode, oxygen from the atmosphere as the cathode active material, and brine for the electrolyte, Mg-air primary batteries can be constructed using inexpensive and abundant materials. Theoretically, these batteries are expected to match lithium-air batteries with regard to performance. However, they do not perform well in terms of battery capacity and operational stability.