Abstract
The lithium-air battery has great potential of achieving specific energy density comparable to that of gasoline. Several lithium oxide phases involved in the charge-discharge process greatly affect the overall performance of lithium-air batteries. One of the key issues is linked to the environmental oxygen-rich conditions during battery cycling. Here, the theoretical prediction and experimental confirmation of new stable oxygen-rich lithium oxides under high pressure conditions are reported. Three new high pressure oxide phases that form at high temperature and pressure are identified: Li(2)O(3), LiO(2), and LiO(4). The LiO(2) and LiO(4) consist of a lithium layer sandwiched by an oxygen ring structure inherited from high pressure ε-O(8) phase, while Li(2)O(3) inherits the local arrangements from ambient LiO(2) and Li(2)O(2) phases. These novel lithium oxides beyond the ambient Li(2)O, Li(2)O(2), and LiO(2) phases show great potential in improving battery design and performance in large battery applications under extreme conditions.