First-Charge Instabilities of Layered-Layered Lithium-Ion-Battery Materials: Relationship of Oxygen Ion Displacement to Mn Migration

Tuesday, 26 May 2015: 10:20
Continental Room B (Hilton Chicago)
J. R. Croy (Argonne National Laboratory), H. Iddir (Materials Science Division, Argonne National Laboratory), K. G. Gallagher, R. Benedek (Argonne National Laboratory), and M. Balasubramanian (Advanced Photon Source, Argonne National Laboratory)
Layered-layered composites with composition xLi2MnO3•(1-x)LiMO2 enable high capacity and energy density Li-ion batteries, but suffer from degradation with cycling. Evidence of atomic instabilities during the first charge are discussed based X-ray absorption spectroscopy, first principles simulation, and existing literature. EXAFS measurements on 0.3Li2MnO3•0.7LiMn0.5Ni0.5O2 during the first charge were analyzed to determine the coordination number deficit of Mn and Ni.