电气双层电容的离子大小和孔径大小之间的关系
Celine Largeot1, Cristelle Portet, John Chmiola
1Université Paul Sabatier, CIRIMAT UNM CNRS 5085, 118 route de Narbonne, 31062 Toulouse Cedex 4, France.
Journal of the American Chemical Society
|February 9, 2008
概括
优化电化学双层电容器 (EDLC) 的性能需要将碳电极孔径大小与电解质离子大小相匹配. 精确调整,在安格斯特罗姆精度范围内,最大限度地提高了先进的储能应用的能量密度.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 电化学双层电容器 (EDLC) 弥合了介电电容器和电池之间的性能差距.
- 对于碳电极孔径大小和电解质离子大小之间对于最佳电容的关系的基本理解仍然不完整.
研究的目的:
- 为了确定在EMI-TFSI离子液中最大电容的TiC衍生碳电极的最佳孔径大小.
- 为了研究孔径大小偏差与离子大小对电容的影响.
- 提出设计具有增强能量密度的EDLC的总体策略.
主要方法:
- 在500°C制造TiC衍生的碳电极.
- 在EMI-TFSI离子液体中电容的电化学表征.
- 电极孔径大小和电解质离子大小的函数的电容分析.
主要成果:
- 当TiC衍生的碳电极孔径大小与EMI-TFSI离子大小 (约. 0.7纳米) 的距离.
- 对于优化的TiC-CDC,记录了超过160F/g和85F/cm3的电容值.
- 观察到显著的电容下降,孔径尺寸偏差距离最佳值仅为一个安格斯特罗姆.
结论:
- 在调整碳电极孔径大小相对于电解质离子大小的亚-安格斯特罗姆精度对于最大化EDLC电容至关重要.
- 这些发现为设计高能量密度EDLC提供了可概括的方法.
- 这一策略已在无溶剂和化电解质上得到验证.
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