TU Darmstadt / ULB / TUbiblio

Fatigue in 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 positive electrodes for lithium ion batteries

Riekehr, Lars ; Liu, Jinlong ; Schwarz, Björn ; Sigel, Florian ; Kerkamm, Ingo ; Xia, Yongyao ; Ehrenberg, Helmut (2016):
Fatigue in 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 positive electrodes for lithium ion batteries.
In: Journal of Power Sources, 325, pp. 391-403. Elsevier B.V., ISSN 03787753,
[Article]

Abstract

Two different Li-rich nickelecobaltemanganese-oxide (Li-rich NCM) active materials with the same nominal composition 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 but different pristine nano structure have been analyzed structurally and electrochemically in different cycling states. For structural characterization, transmission electron microscopy (TEM) and high resolution synchrotron powder diffraction (SXRD) experiments were conducted. The changes in structure with increasing cycle number are correlated with characteristic features in the corresponding electrochemical dQ/dV-profiles that were obtained by galvanostatically cycling the two different active materials. The presented data demonstrates that structural changes upon cycling, e.g. LiMnO2 and spinel formation, strongly depend on the degree oxygen is involved in the reversible charge compensation for delithiation/lithiation. According to our data, firstly a twin-like environment with nanometer dimensions is formed within the R-3m matrix during the initial cycle, which then gradually transforms into a spinel-like structure with increasing cycle number. As another result, we can show that Li2MnO3 to LiMnO2 transformation is not directly dependent in the irreversible oxygen loss in the first cycle but more importantly on transition metal migration. A model is presented explaining the dependency of LiMnO2 and spinel formation on the ability of Li-rich active materials to include oxygen in the charge compensation process. © 2016 Elsevier B.V. All rights reserved.

Item Type: Article
Erschienen: 2016
Creators: Riekehr, Lars ; Liu, Jinlong ; Schwarz, Björn ; Sigel, Florian ; Kerkamm, Ingo ; Xia, Yongyao ; Ehrenberg, Helmut
Title: Fatigue in 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 positive electrodes for lithium ion batteries
Language: English
Abstract:

Two different Li-rich nickelecobaltemanganese-oxide (Li-rich NCM) active materials with the same nominal composition 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 but different pristine nano structure have been analyzed structurally and electrochemically in different cycling states. For structural characterization, transmission electron microscopy (TEM) and high resolution synchrotron powder diffraction (SXRD) experiments were conducted. The changes in structure with increasing cycle number are correlated with characteristic features in the corresponding electrochemical dQ/dV-profiles that were obtained by galvanostatically cycling the two different active materials. The presented data demonstrates that structural changes upon cycling, e.g. LiMnO2 and spinel formation, strongly depend on the degree oxygen is involved in the reversible charge compensation for delithiation/lithiation. According to our data, firstly a twin-like environment with nanometer dimensions is formed within the R-3m matrix during the initial cycle, which then gradually transforms into a spinel-like structure with increasing cycle number. As another result, we can show that Li2MnO3 to LiMnO2 transformation is not directly dependent in the irreversible oxygen loss in the first cycle but more importantly on transition metal migration. A model is presented explaining the dependency of LiMnO2 and spinel formation on the ability of Li-rich active materials to include oxygen in the charge compensation process. © 2016 Elsevier B.V. All rights reserved.

Journal or Publication Title: Journal of Power Sources
Journal Volume: 325
Publisher: Elsevier B.V.
Uncontrolled Keywords: TEM, Synchrotron XRD, Li-rich composites, Irreversible oxygen loss, Anionic charge compensation
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Erneuerbare Energien
11 Department of Materials and Earth Sciences > Material Science > Structure Research
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 20 Jun 2016 10:54
URL / URN: http://dx.doi.org/10.1016/j.jpowsour.2016.06.014
Identification Number: doi:10.1016/j.jpowsour.2016.06.014
Funders: Financial support from the Deutsche Forschungsgemeinschaft DFG within the Research Collaborative Centre 595 “Electrical Fatigue in Functional Materials” (Project T3) is gratefully acknowledged.
Export:
Suche nach Titel in: TUfind oder in Google
Send an inquiry Send an inquiry

Options (only for editors)
Show editorial Details Show editorial Details