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Fleischmann S, Mancini M, Axmann P, Golla-Schindler U, Kaiser U, Wohlfahrt-Mehrens M. Insights into the Impact of Impurities and Non-Stoichiometric Effects on the Electrochemical Performance of Li 2 MnSiO 4. ChemSusChem 2016; 9:2982-2993. [PMID: 27712032 DOI: 10.1002/cssc.201600894] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/29/2016] [Indexed: 06/06/2023]
Abstract
A series of Li2 MnSiO4 samples with various Li, Mn, and/or Si concentrations are reported to study for the first time the effect of impurities and deviation from ideal stoichiometry on electrochemical behavior. Carbon-coated and nanosized powders are obtained at 600 °C and compared with those synthetized at 900 °C. Samples are investigated using XRD, SEM, high-resolution TEM, attenuated total reflection infrared spectroscopy and Brunauer-Emmett-Teller surface area to characterize crystal structure, particle size, impurity amount, morphology, and surface area. Electrochemical performance depends on impurities such as MnO as well as crystallite size, surface area, and non-stoichiometric phases, which lead to the formation of additional polymorphs such as Pmnb and P21 /n of Li2 MnSiO4 at low calcination temperatures. A systematic analysis of the main parameters affecting the electrochemical behavior is performed and trends in synthesis are identified. The findings can be applied to optimize different synthesis routes for attaining stoichiometric and phase-pure Pmn21 Li2 MnSiO4 as cathode material for Li-ion batteries.
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Affiliation(s)
- S Fleischmann
- Accumulators Materials Research (ECM), Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Helmholtzstr. 8, 89081, Ulm, Germany
| | - M Mancini
- Accumulators Materials Research (ECM), Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Helmholtzstr. 8, 89081, Ulm, Germany.
| | - P Axmann
- Accumulators Materials Research (ECM), Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Helmholtzstr. 8, 89081, Ulm, Germany
| | - U Golla-Schindler
- Electron Microscopy Group of Materials Science, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - U Kaiser
- Electron Microscopy Group of Materials Science, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - M Wohlfahrt-Mehrens
- Accumulators Materials Research (ECM), Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Helmholtzstr. 8, 89081, Ulm, Germany
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Marinaro M, Balasubramanian P, Gucciardi E, Theil S, Jörissen L, Wohlfahrt-Mehrens M. Importance of Reaction Kinetics and Oxygen Crossover in aprotic Li-O2 Batteries Based on a Dimethyl Sulfoxide Electrolyte. ChemSusChem 2015; 8:3139-3145. [PMID: 26249807 DOI: 10.1002/cssc.201500600] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/25/2015] [Indexed: 06/04/2023]
Abstract
Although still in their embryonic state, aprotic rechargeable Li-O2 batteries have, theoretically, the capabilities of reaching higher specific energy densities than Li-ion batteries. There are, however, significant drawbacks that must be addressed to allow stable electrochemical performance; these will ultimately be solved by a deeper understanding of the chemical and electrochemical processes occurring during battery operations. We report a study on the electrochemical and chemical stability of Li-O2 batteries comprising Au-coated carbon cathodes, a dimethyl sulfoxide (DMSO)-based electrolyte and Li metal negative electrodes. The use of the aforementioned Au-coated cathodes in combination with a 1 M lithium bis(trifluoromethane)sulfonimide (LiTFSI)-DMSO electrolyte guarantees very good cycling stability (>300 cycles) by minimizing eventual side reactions. The main drawbacks arise from the high reactivity of the Li metal electrode when in contact with the O2 -saturated DMSO-based electrolyte.
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Affiliation(s)
- M Marinaro
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany).
| | - P Balasubramanian
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany)
| | - E Gucciardi
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany)
| | - S Theil
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany)
| | - L Jörissen
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany)
| | - M Wohlfahrt-Mehrens
- ZSW, Center for Solar Energy and Hydrogen Research Baden-Württemberg, Helmholtzstr. 8, 89081 Ulm (Germany)
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Mancini M, Bekaert E, Diemant T, Marinaro M, Biasi LD, Behm R, Wohlfahrt-Mehrens M. Study on the stability of Li2MnSiO4 cathode material in different electrolyte systems for Li-ion batteries. Electrochim Acta 2015. [DOI: 10.1016/j.electacta.2015.07.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gorse S, Kugler B, Samtleben T, Waldmann T, Wohlfahrt-Mehrens M, Schneider G, Knoblauch V. An Explanation of the Ageing Mechanism of Li-Ion Batteries by Metallographic and Material Analysis. ACTA ACUST UNITED AC 2014. [DOI: 10.3139/147.110325] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Li-ion batteries are a key technology for both electro-mobility and stationary energy storage systems. In order to be able to represent and improve their service life in these applications, a better understanding of the processes which lead to the degradation of the individual cells is essential. The work presented in this article focuses on the comparative post mortem analysis of type 18650 commercially available cells containing the state of the art active materials (Cathode: LiMn2O4 (LMO) and Li(Ni1/3Mn1/3Co1/3)O2 (NMC), Anode: Graphite). These cells were subjected to various different ageing procedures. Amongst other effects, the cells investigated revealed signs of crack formation in the LMO- and NMC-particles, a loss in the mechanical integrity of the cathode active mass and plastic deformation of cell structure together with pronounced delamination between the active mass layers, the separator and the current collector.
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Affiliation(s)
- S. Gorse
- Hochschule für Technik und Wirtschaft Aalen , Institut für Materialforschung Aalen, Beethovenstr. 1, 73430 Aalen; e-mails: ,
| | - B. Kugler
- Hochschule für Technik und Wirtschaft Aalen , Institut für Materialforschung Aalen, Beethovenstr. 1, 73430 Aalen; e-mails: ,
| | | | - T. Waldmann
- Zentrum für Solar- und Wasserstoffforschung , Baden-Württemberg (ZSW) Helmholtzstr. 8 , 89081 Ulm
| | - M. Wohlfahrt-Mehrens
- Zentrum für Solar- und Wasserstoffforschung , Baden-Württemberg (ZSW) Helmholtzstr. 8 , 89081 Ulm
| | - G. Schneider
- Hochschule für Technik und Wirtschaft Aalen , Institut für Materialforschung Aalen, Beethovenstr. 1, 73430 Aalen; e-mails: ,
| | - V. Knoblauch
- Hochschule für Technik und Wirtschaft Aalen , Institut für Materialforschung Aalen, Beethovenstr. 1, 73430 Aalen; e-mails: ,
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Köntje M, Memm M, Axmann P, Wohlfahrt-Mehrens M. Substituted transition metal phospho olivines LiMM′PO4 (M = Mn, M′ = Fe, Co, Mg): Optimisation routes for LiMnPO4. PROG SOLID STATE CH 2014. [DOI: 10.1016/j.progsolidstchem.2014.04.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Waldmann T, Wohlfahrt-Mehrens M. In-Operando Measurement of Temperature Gradients in Cylindrical Lithium-Ion Cells during High-Current Discharge. ACTA ACUST UNITED AC 2014. [DOI: 10.1149/2.0031501eel] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Marinaro M, Riek U, Eswara Moorthy S, Bernhard J, Kaiser U, Wohlfahrt-Mehrens M, Jörissen L. Au-coated carbon cathodes for improved oxygen reduction and evolution kinetics in aprotic Li–O2 batteries. Electrochem commun 2013. [DOI: 10.1016/j.elecom.2013.09.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Marinaro M, Theil S, Jörissen L, Wohlfahrt-Mehrens M. New insights about the stability of lithium bis(trifluoromethane)sulfonimide-tetraglyme as electrolyte for Li–O2 batteries. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.06.147] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Lian F, Gao M, Qiu WH, Axmann P, Wohlfahrt-Mehrens M. Fe-doping effects on the structural and electrochemical properties of 0.5Li2MnO3·0.5LiMn0.5Ni0.5O2 electrode material. J APPL ELECTROCHEM 2012. [DOI: 10.1007/s10800-012-0414-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Fröschl T, Hörmann U, Kubiak P, Kučerová G, Pfanzelt M, Weiss CK, Behm RJ, Hüsing N, Kaiser U, Landfester K, Wohlfahrt-Mehrens M. High surface area crystalline titanium dioxide: potential and limits in electrochemical energy storage and catalysis. Chem Soc Rev 2012; 41:5313-60. [DOI: 10.1039/c2cs35013k] [Citation(s) in RCA: 367] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Kinyanjui MK, Axmann P, Wohlfahrt-Mehrens M, Moreau P, Boucher F, Kaiser U. Origin of valence and core excitations in LiFePO(4) and FePO(4). J Phys Condens Matter 2010; 22:275501. [PMID: 21399256 DOI: 10.1088/0953-8984/22/27/275501] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Electronic structures of LiFePO(4) and FePO(4) have been investigated using valence and core electron energy loss spectroscopy (EELS) supported by ab initio calculations. Valence electron energy loss spectra of FePO(4) are characterized by interband transitions found between 0 and 20 eV, which are not observed in LiFePO(4). Spectra are fully analysed using band structure calculations and calculated dielectric functions. In particular, we show that interband transitions observed in FePO(4) spectra originate from the states at the top of the valence band, which have mainly oxygen p character. From core-loss EELS, it is observed that the O-K edge in FePO(4) has a pre-edge peak below the threshold of the main O-K edge. This pre-edge peak is not observed in the O-K spectra of LiFePO(4). The position of the pre-edge peak is determined by a charge transfer process, which shifts the position of the iron 3d bands with respect to the conduction band. The intensity of the pre-edge peak is also determined by the changes in the hybridization of iron 3d and oxygen states as a result of extraction of lithium ions from the LiFePO(4) lattice. We show that the extraction of lithium ions from LiFePO(4) results in large changes in the electronic structure, such that FePO(4) can be considered to be a charge transfer insulator while LiFePO(4) is a typical Mott-Hubbard insulator.
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Affiliation(s)
- M K Kinyanjui
- University of Ulm, Albert Einstein Allee 11, 89081 Ulm, Germany.
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Wohlfahrt-Mehrens M, Heitbaum J. Oxygen evolution on Ru and RuO2 electrodes studied using isotope labelling and on-line mass spectrometry. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0022-0728(87)85237-3] [Citation(s) in RCA: 152] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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