用于快充离子电池的基于乙二的超缩电解质的异常稳定性
Yuki Yamada1, Keizo Furukawa, Keitaro Sodeyama
1Department of Chemical System Engineering, The University of Tokyo , Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|March 25, 2014
概括
研究人员提高了用于先进电池的超缩酸 (AN) 溶液的还原稳定性. 这一突破使得可以在AN中进行可逆间,从而改善反应动力学,使充电速度更快.
科学领域:
- 电化学和材料科学 材料科学
- 先进的电池技术 电池技术
背景情况:
- 稳定的电解质对于高压离子电池和下一代电池 (例如Li-O2) 是至关重要的.
- 基于乙尼 (AN) 的电解质具有高导电性和稳定性,但具有较差的还原稳定性.
- 这种限制阻碍了AN电解质在苛刻的电池系统中的应用.
研究的目的:
- 为了提高乙尼 (AN) 基电解质的还原性稳定性.
- 为了使AN电解质能够在需要高性能的先进电池应用中使用.
- 为了证明可逆的间隔在一个可减少的易受伤害的AN溶剂.
主要方法:
- 研究过的超缩AN溶液 (度大于4moldm(-3)).
- 在一个带有石墨电极的电池系统中应用了超缩的AN电解质.
- 利用第一原理计算和光谱分析来了解电解质的行为.
主要成果:
- 在超缩的AN溶液中实现显著增强的还原稳定性.
- 首次使用基于AN的电解质,证明了可逆与石墨的间歇作用.
- 与传统的商业电解质相比,观察到更快的反应动力学.
结论:
- 超缩的AN溶液表现出独特的还原稳定性,这是由于修改了边界轨道的特征.
- 形成一个由离子和Li+离子组成的流体聚合物网络,有助于增强稳定性.
- 这一进步为在快充和高压电池中使用AN电解质开辟了新的可能性.
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