リチウム電池のためのLi2FeSiO4カトドの構造とリチウム輸送経路
A Robert Armstrong1, Navaratnarajah Kuganathan, M Saiful Islam
1School of Chemistry, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9ST, UK.
Journal of the American Chemical Society
|July 12, 2011
まとめ
Li(2) FeSiO(4) のような新しいリチウム電池カソッドの探索は極めて重要です. コンピュータモデリングは,そのサイクルされた構造が変化し,バッテリーの性能を改善するためにリチウムイオン輸送経路を変更することを明らかにします.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- 固体化学 固体化学
背景:
- Li(2) FeSiO(4) は,大規模なリチウム電池のための有望な低コストのカトド材料です.
- バッテリーサイクル中の構造変化を理解することは,材料の最適化に不可欠です.
研究 の 目的:
- 電気化学サイクル中のLi(2)FeSiO(4) の構造変化を解明する.
- サイクルされた材料におけるリチウムイオン輸送経路の変化を特徴付けるため.
主な方法:
- 準備され,サイクルされたLi(2)FeSiO(4) のX線 difraktion分析.
- 原子構造とイオン拡散経路を決定するための計算モデリング.
主要な成果:
- 準備された γ(s) ポリモルフは,サイクリング時に逆の β(II) ポリモルフに変形します.
- この変換は四面体の逆転を伴い,カチオン-酸素結合と層構造が変化します.
- コンピューターモデリングにより,サイクリングされた構造のジグザグ状の独特のLi (((+) 輸送経路が明らかになり,アースで準備された材料とは異なる.
結論:
- Li(2)FeSiO(4) の構造的進化は,その電気化学的性質に大きく影響する.
- サイクルされた材料における特定されたLi ((+) 輸送機構は,高度なリチウム電池の設計のための洞察を提供します.
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