Structural Evolution of Li2Fe1-yMnySiO4 (y = 0, 0.2, 0.5, 1) Cathode Materials for Li-Ion Batteries upon Electrochemical Cycling

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• 作者：Ruiyong Chen ; Ralf Heinzmann ; Stefan Mangold ; V.S. Kiran Chakravadhanula ; Horst Hahn ; Sylvio Indris
• 刊名：The Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：January 17, 2013
• 年：2013
• 卷：117
• 期：2
• 页码：884-893
• 全文大小：655K
• 年卷期：v.117,no.2(January 17, 2013)
• ISSN：1932-7455

文摘

Nanocrystalline Li₂Fe_1-yMn_ySiO₄ (y = 0, 0.2, 0.5, 1) powders with in situ carbon coating have been prepared by a sol鈥揼el route and their structural evolution during the first electrochemical charge鈥揹ischarge cycles has been investigated in detail by X-ray diffraction in combination with ⁷Li MAS NMR, ⁵⁷Fe M枚ssbauer spectroscopy and in situ X-ray absorption spectroscopy. These results provide detailed information about the amorphization, phase transitions and the partially reversible change in the local environment of Li nuclei upon cycling. The redox processes of the metal cations responsible for the cycling performance of the first few cycles and for the cyclability are also derived from the combined structural characterizations.