高性能リチウム/硫黄電池のための耐久性のある炭素コーティングのLi2(S) コアシェルの球体
Caiyun Nan1, Zhan Lin, Honggang Liao
1Department of Chemical and Biomolecular Engineering, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|March 4, 2014
まとめ
研究者らは,安定した炭素コーティングされた硫化リチウム (Li2S@C) のコアシェル粒子を開発した. このイノベーションは,硫化リチウムを強化しています.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 硫化リチウム (Li2S) は理論的に高い容量を有しており,有望なカトド材料となっています.
- Li2Sの実用的な応用は,低サイクル寿命とレート能力によって妨げられています.
- 安定したLi2Sベースのカトドの開発は,先進的なエネルギー貯蔵に不可欠です.
研究 の 目的:
- サイズ制御された硫化リチウム球を合成するために.
- 化学蒸気堆積 (CVD) を使用して,安定した炭素コーティングされた硫化リチウムコアシェル (Li2S@C) 粒子を生成します.
- 新しい Li2S@C カソード材料の電気化学性能を評価するために.
主な方法:
- サイズ制御されたLi2S球の合成.
- 炭素コーティングのための化学蒸気沈殿 (CVD).
- Li2S@C複合カトドの電気化学試験について.
主要な成果:
- 保護性および導電性炭素殻を持つLi2S@Cコアシェル粒子を成功して合成しました.
- 972 mAh g−1 Li2S (1394 mAh g−1 S) の高い初期放電容量を0.2Cで達成しました.
- 証明された安定したサイクリング性能と最小の形態の変化は,0.5Cで400サイクル後に,高 Li2S 含有量 (88 wt%) にもかかわらず,0.5C で 400サイクル後に示されています.
結論:
- 炭素コーティングされたLi2S@Cコアシェル粒子は,サイクルの寿命と速度能力を大幅に改善します.
- 開発されたLi2S@C素材は,高性能リチウムイオン電池における実用的な応用の可能性を示しています.
- このアプローチは,高容量カトド材料の安定化のための実行可能な戦略を提供します.
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