Metal-air (or metal oxygen) batteries have been a research topic for many decades with the hope of creating high specific energy batteries. However, most of this research is conducted at room temperatures, where a number of challenges remain. For aqueous metal-oxygen batteries, such as the aluminum-air primary cell, corrosion reactions between the aqueous electrolyte and negative electrode significantly decrease available capacity of the device. While this problem can be mitigated by using high purity metals, this significantly increases cost . Non-aqueous electrolytes have been explored for a number of different metal-air battery systems, particularly for the lithiumair system, but the insoluble nature of metal oxide discharge products results in passivation of the air electrode . Furthermore, the catalysts used in non-aqueous lithium-air batteries are sensitive to atmospheric contaminants such as water and CO2. Some have proposed to enclose a metal-air battery in a sealed pressure vessel to mitigate the contaminant problem. However, in this case the energy density is significantly limited and may not be competitive compared to even current lithium-ion batteries .