Abstract
Spinel transition metal oxides are important electrode materials for lithium-ion batteries, whose lithiation undergoes a two-step reaction, whereby intercalation and conversion occur in a sequential manner. These two reactions are known to have distinct reaction dynamics, but it is unclear how their kinetics affects the overall electrochemical response. Here we explore the lithiation of nanosized magnetite by employing a strain-sensitive, bright-field scanning transmission electron microscopy approach. This method allows direct, real-time, high-resolution visualization of how lithiation proceeds along specific reaction pathways. We find that the initial intercalation process follows a two-phase reaction sequence, whereas further lithiation leads to the coexistence of three distinct phases within single nanoparticles, which has not been previously reported to the best of our knowledge. We use phase-field theory to model and describe these non-equilibrium reaction pathways, and to directly correlate the observed phase evolution with the battery's discharge performance.
| Original language | English (US) |
|---|---|
| Article number | 11441 |
| Journal | Nature communications |
| Volume | 7 |
| DOIs | |
| State | Published - May 9 2016 |
Funding
This research used resources of the Center for Functional Nanomaterials, which is a US DOE Office of Science Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704. X.Y., E.H., K.S., H.G. and X.-Q.Y. were supported by the US DOE, the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies under Contract No. DE-SC00112704. We acknowledge the technical support by Dr Wenqian Xu from Beamline 17-BM-B of Advanced Photon Source at Argonne National Laboratory. S.Z., H.Y. and C.B.M. acknowledge the support of MRSEC award No. DMR-1120901. S.Z. also acknowledges the support of the NatureNet Science Fellowship. Q.M. and Yimei Z. are supported by DOE/BES, Division of Materials Science and Engineering, under Contract No. DE-SC0012704. Those in situ and analytical TEM experiments performed by J.L. and E.A.S. were supported as part of the Center for Mesoscale Transport Properties, an Energy Frontier Research Center supported by the US Department of Energy, Office of Science, Basic Energy Sciences, under award #DE-SC0012673. Yizhou Z. and Y.M. acknowledge the support of the Minta Martin award at University of Maryland, and the computational resources from Extreme Science and Engineering Discovery Environment (XSEDE) supported by the National Science Foundation Grant No. TG-DMR130142 and from the University of Maryland supercomputing resources. We thank Dr Peng Bai for helpful discussions on phase-field simulaitons.
ASJC Scopus subject areas
- General Physics and Astronomy
- General Chemistry
- General Biochemistry, Genetics and Molecular Biology
