Аннотация:Transition to the renewable energy sources (solar, wind energies, etc.) and electrified transport is needed to improve our environment. For these purpose long-lived, safe, and affordable rechargeable batteries are of demand. Metal-air batteries, and especially lithium-air batteries with aprotic electrolytes promise very high specific energy in comparison to the LIBs and thus gained lots of attention in recent decades. The lithium-air battery consists of a lithium anode, a porous air cathode, and an electrolyte composed of a lithium salt dissolved in nonaqueous, organic solvent. In 1996, Abraham et al. reported the first rechargeable nonaqueous lithium-O2 battery, that laid the foundation for a new field and other analogous systems such as Na-O2 and K-O2 batteries. Significant efforts were undertaken a decade ago to commercialize Li-air batteries, which failed but prompted the research aimed at a deeper understanding of the unclear underpinning chemistry and electrochemistry. Extensive studies uncovered fundamental obstacles limiting the further development of nonaqueous Li-O2 batteries, including limited capacity, electrode passivation and degradation, poor cycling and safety issues related to Li metal anode. This chapter is aimed to shed the light on the diversity of mechanisms and elementary processes occurring in this system.