アセトニトリル中のリチウム窒素の電気化学的振る舞いを,量子化学的方法で予測する
Vyacheslav S Bryantsev1, Jasim Uddin, Vincent Giordani
1Liox Power, Inc., 129 N. Hill Ave., Suite 103, Pasadena, California 91106, United States.
Journal of the American Chemical Society
|February 5, 2014
まとめ
有機電解質におけるリチウム窒素 (LiNO2) の安定性は,充電可能なリチウム酸素電池にとって極めて重要です. この研究では,LiNO2がバッテリー充電中にリチウム窒素 (LiNO3) を再生し,電解質の性能を向上させることが明らかになりました.
科学分野:
- 電気化学 電気化学について
- マテリアルサイエンス 材料科学
- コンピューティング・ケミストリー
背景:
- 電解質の安定性は,リチャージ可能なリチウム酸素 (Li-O2) バッテリーにとって非常に重要です.
- リチウムナイトレート (LiNO3) はリチウムアノドを安定させるが,副産物であるリチウムナイトライト (LiNO2) を生成する.
- Li-O2電池の電解質におけるLiNO2の振る舞いは十分に理解されていません.
研究 の 目的:
- アセトニトリル (AN) 溶媒におけるLiNO2の化学的および電気化学的振る舞いを調査する.
- LiNO2酸化反応の反応機構と潜在的な再生経路を解明する.
- Li-O2電池の性能に対するLiNO2の行動の影響を評価する.
主な方法:
- 密度関数理論 (DFT) とカップリングされたクラスター計算.
- 中性分子のための暗黙の溶解モデルとイオンのための混合クラスター/連続体モデル.
- 電気化学的検証のためのサイクル電圧測定実験.
主要な成果:
- 窒素化合物の予測された酸化還元電位は,高い精度 (0.10Vの平均誤差) を示しています.
- ANにおけるLiNO2酸化は,ダイマー形成,オートイオン化,およびニトロシルイオン (NO+) との反応を含む.
- シミュレートされたサイクルボルトアモグラムは,実験データと密接に一致し,提案された反応機構をサポートします.
結論:
- 充電条件下でLiNO2をLiNO3に再生するメカニズムが提案されています.
- この再生経路は,酸素が存在するリチウム-O2電池に特異的です.
- LiNO2の振る舞いを理解することは,電解質の安定性を高め,充電可能なLi-O2電池の開発の鍵です.
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