溶塩 リチウム 酸素 バッテリー
Vincent Giordani1, Dylan Tozier2, Hongjin Tan1
1Liox Power, Inc. , 129 N. Hill Ave., Pasadena, California 91106, United States.
Journal of the American Chemical Society
|February 13, 2016
まとめ
この研究は,リチウム酸素電池のための新しい溶解塩電解質を導入し,エネルギー効率とレート能力を改善します. 新しいアプローチは伝統的な電解質の課題を克服し,より安定したリチウム過酸化物の形成と分解を可能にします.
科学分野:
- 電気化学
- 材料科学
- エネルギー貯蔵
背景:
- リチウム酸素 (Li/O2) バッテリーは理論的には高い容量ですが,不安定な電解質や電極材料で課題に直面しています.
- 伝統的な有機電解質は揮発性があり 空気不耐性があり バッテリーの性能を制限します
研究 の 目的:
- 有機電解質を溶けた窒素塩に置き換えて,安定で効率的な中間温度Li/O2電池を開発する.
- 溶けた塩の電解質を用いたリチウム/O2電池の電気化学的振る舞いと性能を調査する.
主な方法:
- リチウムアノド,溶けた窒素ベースの電解質 (LiNO3-KNO3ユーテクティック) と80°C以上で動作する多孔性炭素カトドを使用した.
- 現場圧力およびガス分析,スキャニング電子顕微鏡 (SEM),および回転円盤電極電圧測定 (RDEV) を用いる.
主要な成果:
- 溶けた塩のLi/O2電池で高いエネルギー効率 (∼95%) と改善されたレート能力を達成しました.
- リチウム過酸化物 (Li2O2) の安定した形成と分解が示され,放電/充電余電位が低い (∼50 mV).
- 炭素の反応性と制御されていないLi2O2の降水が,サイクル寿命の主要な制限として特定された.
結論:
- 溶けた窒素電解質は,安定して効率的なリチウム/O2電池を開発するための有望な代替手段です.
- Li2O2の溶解性と安定性は,電池の性能を向上させる.
- 炭素カソッドの分解を緩和し,サイクル寿命を延長するためにLi2O2の降水を制御することに焦点を当てなければならない.
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