アニオンと溶媒による交互相は,極限条件下でのリチウムイオン電池を可能にします
Sha Tan1, Oleg Borodin2, Nan Wang1
1Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States.
Journal of the American Chemical Society
|October 25, 2024
まとめ
研究者らは,リチウムイオン電池 (LIB) のための新しい電解質を開発し,2,2-二エチル炭酸 (DFDEC) 溶媒を使用した. この画期的な技術により,高速充電,高い安定性,高度なエネルギー貯蔵アプリケーションの幅広い温度性能が実現できます.
科学分野:
- 材料科学
- 電気化学
- エネルギー貯蔵
背景:
- リチウムイオン電池 (LIB) は,極端な温度や高速充電などの要求の高いアプリケーションに高度な電解質を必要とします.
- 現在の電解質は,効率的なイオン輸送と安定したインターフェーズ形成の間のトレードオフに直面します.
- アニオン由来インターフェーズは,弱溶解性溶媒のためにイオン輸送を妨げることができます.
研究 の 目的:
- 効率的なイオン輸送と 堅固なインターフェーズ形成のバランスをとる 新しい電解質を設計する
- 溶媒とアニオンの両方を同期的なインターフェーズ構築に使用することを探求する.
- 高性能のLIB電解質のための有望な溶媒を特定する.
主な方法:
- 新しい溶媒のスクリーニングにより,2,2-ジフローロエチルエチル炭酸 (DFDEC) が特定されました.
- 主な溶媒としてDFDEC,塩としてリチウムビスフローロスルフォニルイミド (LiFSI) を用いた新しい電解質の製剤.
- 開発された電解質でグラファイトのダラダラLiNi0.8Mn0.1Co0.1O2 (NMC811) の完全な細胞を試験する.
主要な成果:
- 新しい電解質は,4. 5Vのカットオフ電圧で高速充電と長期サイクルの安定性を可能にします.
- 500サイクル後に84.3%の容量保持を達成し,平均クーロンビック効率 (CE) は99.93%であった.
- 幅広い温度範囲 (-20 °Cから60 °C) で安定したバッテリーサイクルが実証されています.
結論:
- 溶媒とアニオンの両方を利用してインターフェーズ形成は,高性能LIBのための有望な戦略を提供します.
- DFDECベースの電解質は,相間安定性とイオン伝導性のバランスをとります.
- 開発された電解質は,高速充電と幅広い温度での動作を必要とする次世代のリチウムイオンバッテリーにとって大きな可能性を秘めています.
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