(670d) A Lithium-Oxygen Battery Based on Lithium Superoxide | AIChE

(670d) A Lithium-Oxygen Battery Based on Lithium Superoxide


Lu, J. - Presenter, Argonne National Laboratory
Batteries based on sodium and potassium superoxide have recently been reported. However, there have been no reports of a battery based on lithium superoxide (LiO2), despite much recent research into the lithium-oxygen (Li-O2) battery because of its potential high energy density. Several recent studies of Li-O2 batteries have found evidence of LiO2 being formed as one component of the discharge product along with lithium peroxide (Li2O2). In addition, theoretical calculations have indicated that some forms of LiO2 may have a significant lifetime. The recent reports of the existence of LiO2 as one component in the discharge product would suggest it might be formed by itself for use in a battery. However, solid LiO2 has been difficult to synthesize in pure form because it is thermodynamically unstable with respect to disproportionation to Li2O2. Here we show for the first time that crystalline LiO2 can be stabilized in a Li-O2 battery by using a suitable cathode material, with no evidence for the presence of Li2O2 from various characterization techniques. A novel templating growth mechanism involving the use of Ir nanoparticles on the cathode surface may be responsible for the crystalline LiO2 growth. Our results demonstrate that the LiO2 formed in the Li-O2 battery is stable enough that it can be repeatedly charged and discharged with a very low charge potential (~3.2V). We anticipate that this discovery will lead to future research into methods to synthesize and stabilize LiO2. This can open the avenue for high-energy density lithium superoxide-based batteries as well as other potential uses such as a source of oxygen storage.