リチウムデンドライトの自己加熱による治癒
Lu Li1, Swastik Basu1, Yiping Wang2
1Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
Science (New York, N.Y.)
|March 31, 2018
まとめ
電流の高密度は リチウムデンドライトを 驚くほど回復させます この自己修復メカニズムは,リチウム硫黄電池の安定したサイクルを効率的に可能にします.
科学分野:
- 材料科学
- 電気化学
- エネルギー貯蔵
背景:
- リチウム金属電極は,高エネルギー密度の充電電池に不可欠です.
- リチウム塗装/剥離中のデンドライトの成長は,バッテリーの故障と安全性の問題を引き起こします.
- この問題は通常,高い電流密度によって悪化します.
研究 の 目的:
- リチウムデンドライトの異常な進化を調査する
- デンドライトの緩和のための高密度の電流の可能性を調査する.
- リチウム硫黄電池の 安全で効率的なサイクルを可能にします
主な方法:
- 異なる電流密度でリチウム塗装と剥離の実験調査.
- デンドライトの形状と表面の進化を監視する.
- リチウム金属電極に高電流密度処理を施す.
- リチウム硫黄電池は,処理された電極で回転しています.
主要な成果:
- デンドライトの自己治癒には,臨界電流密度 (~9 mA/cm2) が確認された.
- 高密度の電流は自己加熱を誘導し,リチウムの表面移動と治癒を促進します.
- リチウムの表面を高密度電流で 繰り返し滑らかにしました
- リチウム-硫黄電池の安全なサイクルが実証され,高キュロンビック効率です.
結論:
- 高い電流密度では,デンドライトの成長による有害な影響を自己治癒によって逆転させることができます.
- この新しいアプローチは,デンドライトのないリチウム金属アノドを展開するための経路を提供します.
- より安全で高性能の充電電池,特にリチウム硫黄系の開発を可能にします.
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