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Title: Stress Induced Charge-Ordering Process in LiMn 2O 4

Abstract

In this letter we report the stress-induced Mn charge-ordering process in the LiMn 2O 4 spinel, evidenced by the lattice strain evolutions due to the Jahn–Teller effects. In situ neutron diffraction reveals the initial stage of this process at low stress, indicating the eg electron localization at the preferential Mn sites during the early phase transition as an underlying charge-ordering mechanism in the charge-frustrated LiMn 2O 4. The initial stage of this transition exhibits as a progressive lattice and charge evolution, without showing a first-order behavior.

Authors:
 [1];  [2];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tianjin Univ. (China)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1340435
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Materials Research Letters
Additional Journal Information:
Journal Volume: 5; Journal Issue: 2; Journal ID: ISSN 2166-3831
Publisher:
Taylor and Francis
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Chen, Yan, Yu, Dunji, and An, Ke. Stress Induced Charge-Ordering Process in LiMn2O4. United States: N. p., 2016. Web. doi:10.1080/21663831.2016.1197858.
Chen, Yan, Yu, Dunji, & An, Ke. Stress Induced Charge-Ordering Process in LiMn2O4. United States. doi:10.1080/21663831.2016.1197858.
Chen, Yan, Yu, Dunji, and An, Ke. Mon . "Stress Induced Charge-Ordering Process in LiMn2O4". United States. doi:10.1080/21663831.2016.1197858. https://www.osti.gov/servlets/purl/1340435.
@article{osti_1340435,
title = {Stress Induced Charge-Ordering Process in LiMn2O4},
author = {Chen, Yan and Yu, Dunji and An, Ke},
abstractNote = {In this letter we report the stress-induced Mn charge-ordering process in the LiMn2O4 spinel, evidenced by the lattice strain evolutions due to the Jahn–Teller effects. In situ neutron diffraction reveals the initial stage of this process at low stress, indicating the eg electron localization at the preferential Mn sites during the early phase transition as an underlying charge-ordering mechanism in the charge-frustrated LiMn2O4. The initial stage of this transition exhibits as a progressive lattice and charge evolution, without showing a first-order behavior.},
doi = {10.1080/21663831.2016.1197858},
journal = {Materials Research Letters},
number = 2,
volume = 5,
place = {United States},
year = {Mon Jul 25 00:00:00 EDT 2016},
month = {Mon Jul 25 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 2works
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  • The in situ XAFS technique has been applied for the first time to reveal variations in the local structures of Mn atoms during the charge-discharge process of LiMn{sub 2}O{sub 4}, Li(Mn{sub 1.93}Li{sub 0.07})O{sub 4}, and Li(Mn{sub 1.85}Li{sub 0.7})O{sub 4} cathode materials of lithium-ion secondary batteries. It has been demonstrated that the valence state of manganese is in a linear correlation with the peak energy of the Mn K-edge XANES spectrum. EXAFS analysis disclosed the {sup 3}+ Mn{sup 4}+ coexistence of Mn and in LiMn{sub 2}O{sub 4}, with two distinct Mn-O bond distances of 1.98 and 1.88{angstrom} for the Mn{sup 3+}.
  • The actual structure of the vanadium phosphate K{sub 6}(VO){sub 2}(V{sub 2}O{sub 3}){sub 2}(PO{sub 4}){sub 4}(P{sub 2}O{sub 7}) has been determined, using a much larger single crystal than previously used for the isostructural Rb-phase. The actual supercell is four times larger than the corresponding orthorhombic subcell with a=26.777A, b=28.480A, c=6.972A, {alpha}={beta}={gamma}=90 deg. The structure resolution, performed in the triclinic space group C-1, shows that the P{sub 2}O{sub 7} groups alone are responsible for the superstructure, all the other atoms keeping the atomic positions of the orthorhombic subcell. This structural study shows a perfect ordering of the P{sub 2}O{sub 7} groups inmore » the actual structure, in contrast to the results obtained from the subcell. Concomitantly, the V{sup 4+} and V{sup 5+} are found to be ordered in the form of [110] stripes.« less
  • Here in this study, synchrotron X-ray nano-computed tomography at Advanced Photon Source in Argonne National Laboratory has been employed to reconstruct real 3D active particle morphology of LiMn 2O 4 (LMO) commonly used in lithium-ion batteries (LIBs). For the first time, carbon-doped binder domain (CBD) has been included in the electrode structure as a 108 nm thick uniform layer using image processing technique. With this unique model, stress generated inside four LMO particles with a uniform layer of CBD has been simulated, demonstrating its strong dependence on local morphology (surface concavity and convexity), and the mechanical properties of CBD suchmore » as Young’s modulus. Specifically, high levels of stress have been found in vicinity of particle’s center or near surface concave regions, however much lower than the material failure limits even after discharging at the rate as high as 5C. On the other hand, the stress inside CBD has reached its mechanical limits when discharged at 5C, suggesting that it can potentially lead to failure by plastic deformation. The findings in this study highlight the importance of modeling LIB active particles with CBD and its appropriate compositional design and development to prevent the loss of electrical connectivity of the active particles from the percolated solid network and power losses due to CBD failure.« less
  • The process of sol–gel synthesis was applied to obtain LiMn{sub 1.5}M{sub 0.5}O{sub 4} (M=Al, Mg, Ni, Fe) and LiMn{sub 2}O{sub 4}/TiO{sub 2} nanopowders. The samples were characterized by following methods: X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), X-ray photoelectron spectroscopy (XPS) and SQUID magnetometry. XPS was used to examine the chemical composition and oxidation state of manganese, in particular the Mn{sup 3+}/Mn{sup 4+} ratio from the deconvolution of the complex Mn3p lines. The size of the grains and crystallites were independently obtained from SEM images and XRD patterns, respectively. In all the cases a critical interplay of electronic (Mn{sup 3+}/Mn{supmore » 4+} ratio), structural (unit cell volume) and magnetic properties was observed depending on the synthesis process. - Graphical abstract: SEM image of Li{sub 0.79}Ni{sub 0.41}Mn{sub 1.35}O{sub 4.45} sample. Display Omitted - Highlights: • LiMn{sub 1.5}M{sub 0.5}O{sub 4} (M=Al, Mg, Ni, Fe) and LiMn{sub 2}O{sub 4}/TiO{sub 2} obtained by sol–gel method. • XRD method was used to determine the crystal structure. • SEM/EDX imaging have been done. • XPS electronic structure was examined and discussed. • Experimental effective magnetic moment and the calculated one were compared.« less
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