Revolutionizing Li-Battery Infrastructure for Energy Storage Applications: Short Term and Long Term Solutions

Abstract

The invention of the lithium ion and more recently lithium-air (oxygen) batteries has spurred great interest due to their high energy and power densities. Here, we report two possible solutions for Li based batteries; æShort Term: High capacity cathode materials based on Li-rich layered-layered compositions are in the process of being developed. When fully developed, this class of material is expected to exhibit a cathode capacity of ~280 mAh/g which has almost double capacity compared to commercial Li-ion batteries. Major problem of Li rich material is that high rate capabilities are low. We recently found that some judicious metal modifications can enhance the rate capabilities of Li rich materials which are projected to replace current cathode technology in the next 5 years. A report of recent progress will be presented. æææææææLong Term: The lithium oxygen battery has been aggressively pursued by researchers around the world as a consequence of being the most energy dense system of all possible battery couples. Currently the technology generally is recognized as converting lithium metal and oxygen into lithium peroxide through the course of the cell discharge. This process corresponds to achieving only 70% of the total theoretical energy density possible for the system. Full reduction of the oxygen to the monoxide lithia would allow for the maximum energy density of the materials in the battery. Details of the mechanism have been studied in half cell experiments as well as cathode analysis. A report on the enhancement of the discharge process is also included.