より小さな硫黄分子は,より優れたリチウム硫黄電池を約束します
Sen Xin1, Lin Gu, Na-Hong Zhao
1Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, Beijing, PR China.
Journal of the American Chemical Society
|October 30, 2012
まとめ
研究者らは,小さな硫黄分子を使って,新しいリチウム硫黄電池を開発した. このアプローチは,容量の衰えを防止し,高エネルギー貯蔵ソリューションの道を開くことで,バッテリーの性能と長寿を大幅に改善します.
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
- エネルギー貯蔵 エネルギー貯蔵
背景:
- リチウム硫黄 (Li-S) バッテリーは,理論上のエネルギー密度が高く,現在のリチウムイオン技術を上回ります.
- Li-S電池の適用を阻害する主な課題は,硫黄カトドの伝導性が低下し,溶性ポリ硫化 intermediates によって引き起こされる容量減少です.
- ポリ硫化物形成による硫黄の損失は,実用的なLi-S電池の重要な障害となっている.
研究 の 目的:
- リチウム硫黄電池の容量減少問題に対処するために.
- 硫黄の損失を軽減する新しいカトド材料を開発する.
- Li-S電池の電気化学的性能と安定性を高めるために.
主な方法:
- 導電性微孔炭素マトリックス内の転移性小硫黄分子 (S(2-4) の合成.
- 閉じ込められたS(2-4) をLi-S電池の新しいカトド材料として利用する.
- 特定の容量,サイクル安定性,速度能力の評価のための電気化学的特徴付け.
主要な成果:
- 閉じ込められたS(2-4) カトドは,S(8) とS(4)(2-) の中間物質の間の不利な移行を効果的に防ぐ.
- このコンセプトに基づいたLi-S電池は,高い比容量と良好なサイクル安定性を示した.
- 優れた速度能力が観察され,改善された電気化学的振る舞いを示しました.
結論:
- 硫黄をより小さなアロトロップ,特に限られたS2~4で制御することで,Li-S電池の容量衰えを効果的に軽減します.
- このアプローチは,実用的な高エネルギー密度バッテリーへの有望な経路を提供します.
- 開発されたLi-S電池は,携帯電子機器,電気自動車,大規模エネルギー貯蔵における応用の可能性を示しています.
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