高圧リチウム金属電池のヘクササイクリックコーディネートエーテル電解質におけるフッ素化の役割
Lan-Qing Wu1, Zhe Li1, Zhen-Yu Fan1
1Frontiers Science Center for New Organic Matter, Renewable Energy Conversion and Storage Center (RECAST), Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071, China.
Journal of the American Chemical Society
|February 21, 2024
まとめ
部分的に酸化エーテル,特に -CHF2グループを持つものは,高圧リチウム金属電池 (LMB) の有望性を示しています. これらの電解質はイオン輸送と安定性を改善し,弱体条件下でも長いサイクル寿命を可能にします.
科学分野:
- 電気化学
- 材料科学
- バッテリー技術
背景:
- フッ素エーサーは,その安定性のために,高性能リチウム金属電池 (LMB) の鍵です.
- フッ素化がイオン溶解にどのように影響するかを理解することは,電解質設計を最適化するために不可欠です.
- ほとんどの現在の電解質は -CF3グループを使用しており,他の化効果の探求を制限しています.
研究 の 目的:
- LMBの電解剤として,さまざまなレベルの化 (-CH2F, -CHF2, -CF3) を有する化エーテルを合成し,評価する.
- 溶解構造,イオン輸送,およびリチウム堆積に対するフッ素化の影響を調査する.
- 高圧LMBでのこれらの電解質の性能を評価する.
主な方法:
- ヘクササイクルの調整エーサーの合成:EMP,F1EMP,F2EMP,F3EMP
- 電気化学的特徴:溶解構造,リチウムイオン輸送,リチウム堆積運動,高圧安定性
- 理論的な計算とスペクトル分析
- 高電圧カトドと限られた/少ない電解質条件で全セル試験.
主要な成果:
- 溶解力はフッ素化が増加するにつれて低下し,イオン伝導性が低下する.
- 部分的にフッ素化されたエーテル (-CHF2) は,より高いLi+転送数と交換電流密度を示します.
- F2EMP電解質は,高圧LMBで168サイクルにわたって80%の容量保持を示した.
- 精度の低い電解質と陽極のない条件下で優れた性能を達成した.
結論:
- フッ素化の程度は,LMBの電解質特性と性能に大きな影響を与えます.
- -CHF2ベースのフッ素エーサーは,高電圧の用途に最適のバランスを提供します.
- この研究は,実用的な高電圧LMBのための高度な酸化エーテル電解質の設計のための洞察を提供します.
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