First Evidence of Manganese–Nickel Segregation and Densification upon Cycling in Li-Rich Layered Oxides for Lithium Batteries
- 22 July 2013
- journal article
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 13 (8), 3857-3863
- https://doi.org/10.1021/nl4019275
Abstract
Lithium-rich manganese-based layered oxides Li[LixMnyTM1–x–y]O2 with TM standing for Ni, Co, or Fe are of great interest as cathode materials for lithium ion batteries. Indeed, among all of the materials, they offer the highest rechargeable capacity and energy density. However, when used, they suffer from complex evolutions that need to be understood before their practical use. Here we report on such evolutions studied using advanced transmission electron microscopy. Structural modifications are directly observed at the atomic scale using Cs corrected STEM HAADF imaging technique, and the chemical modifications are probed by the means of STEM EELS experiments. For the first time, segregation between nickel and manganese close the particle surface is pointed out. Finally, observed evolutions are correlated within a proposed mechanism that leads to the densification of the material. Our results allow understanding the link between the decrease of electrochemical performance and these evolutions occurring into the material upon cycling.Keywords
This publication has 25 references indexed in Scilit:
- Formation of the Spinel Phase in the Layered Composite Cathode Used in Li-Ion BatteriesACS Nano, 2012
- In situ investigations of a Li-rich Mn–Ni layered oxide for Li-ion batteriesJournal of Materials Chemistry, 2012
- Countering the Voltage Decay in High Capacity xLi2MnO3•(1–x)LiMO2Electrodes (M=Mn, Ni, Co) for Li+-Ion BatteriesJournal of the Electrochemical Society, 2012
- Li2MnO3-based composite cathodes for lithium batteries: A novel synthesis approach and new structuresElectrochemistry Communications, 2011
- Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical studyEnergy & Environmental Science, 2011
- Building better batteriesNature, 2008
- Comments on the structural complexity of lithium-rich Li1+xM1−xO2 electrodes (M=Mn, Ni, Co) for lithium batteriesElectrochemistry Communications, 2006
- Advances in manganese-oxide ‘composite’ electrodes for lithium-ion batteriesJournal of Materials Chemistry, 2005
- The significance of the Li2MnO3 component in ‘composite’ xLi2MnO3·(1−x)LiMn0.5Ni0.5O2 electrodesElectrochemistry Communications, 2004
- Layered Cathode Materials Li[Ni[sub x]Li[sub (1/3−2x/3)]Mn[sub (2/3−x/3)]]O[sub 2] for Lithium-Ion BatteriesElectrochemical and Solid-State Letters, 2001