"Lithium–air (Li-air) batteries have potentially much higher gravimetric energy storage density compared to all other battery chemistries. If successfully developed, this (charged) battery could compete with gasoline as an energy source for electric vehicles. However, in order to fulfill its promise and satisfy the key criteria for a practical electric vehicle propulsion battery, numerous scientific and technical challenges must be overcome. These include the voltage gap between the charge and discharge, inefficient cycling and limited practical specific energy. Like other battery technologies, its performance can be significantly improved by understanding the fundamental battery chemistry occurring during the electrochemical cycle. In the case of the Li-air battery the discharge and charge mechanisms are strongly dependent on the choice of electrolyte solvent, the presence of catalytic species in the cathode, which decrease the charging potential and surprisingly affect the capacity, and the porosity/surface area of the composite carbon cathode. A quantitative understanding of the electrochemical reactions (and parasitic side reactions) during the cell cycle is a necessary aspect in the development of a practical rechargeable Li-air battery. Nuclear magnetic resonance (NMR) can allow us to monitor these chemical processes, providing unique molecular and atomic information on these often disordered and amorphous materials. Here we propose to apply existing and novel solid state NMR techniques in the study of Li-air batteries under ex-situ and in-situ operating conditions. By real time monitoring of the formation and disassociation of lithium containing species we expect to derive a mechanistic description of the cell's chemistry in the presence of various electrolyte environments and catalytic species, relate this to its electrochemical performance, and suggest how the cell can be improved."
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