Ionic Liquid Mixtures for Supercapacitor Applications: Synergy of Electrochemistry, NMR, and Simulations

用于超级电容器应用的离子液体混合物：电化学、核磁共振和模拟的协同作用

• 批准号: 465206506
• 负责人: Professor Dr. Volker Presser
• 金额: --
• 依托单位: Leibniz-Institut für Neue Materialien gGmbH (INM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/465206506?language=en
• 关键词: Ionic; Liquid; Mixtures; Supercapacitor; Applications

The ever-growing global energy demand requires developing novel energy-storage technologies to increase energy production from renewable sources and the transition from hydrocarbon-based fuel to electrical drive. Supercapacitors with nanoporous electrodes have emerged as a critical energy-storage technology, offering high power densities and remarkable cyclability. However, they provide only moderate energy densities compared with conventional batteries and limited electrochemical performances at low temperatures. Neat ionic liquids (ILs) as an electrolyte allow high operating voltages (>3.5 V) and boost the energy storage, but the reduced ion mobility lowers the power density.Increasing the energy storage without compromising the power density would make these ecologically-friendly energy storage systems more broadly applicable. Recently, few studies showed that mixing different ILs improves supercapacitor performance by extending the electrochemical window and temperature range. While these reports are encouraging, there is no deep understanding of the underlying physical mechanisms. Many critical questions remain unanswered: How do ion properties in a mixture affect the bulk and in-pore diffusivity of ions and ultimately the charging dynamics? How does the electrochemical performance vary with the temperature? How to match the pore size and ion sizes in a mixture to maximize the stored energy? What is the relationship between the carbon structure/pore sizes and ion kinetics during charging? These are just some of the key issues essential for further development in this field. Our project addresses these questions by combining electrochemistry, in-situ nuclear magnetic resonance (NMR) measurements, and molecular simulations. We will scrutinize how the electrochemical performance is correlated with the properties

不断增长的全球能源需求要求开发新型能源储存技术，以增加可再生能源的能源生产，并从碳氢化合物燃料过渡到电力驱动。具有纳米多孔电极的超级电容器已成为一种关键的储能技术，提供高功率密度和卓越的循环能力。然而，与传统电池相比，它们仅提供中等的能量密度，并且在低温下的电化学性能有限。纯离子液体作为电解质可以提供较高的工作电压（>3.5 V），提高储能能力，但离子迁移率降低会降低功率密度，在不影响功率密度的前提下提高储能能力将使这些生态友好的储能系统得到更广泛的应用。最近，很少有研究表明，混合不同的离子液体通过扩大电化学窗口和温度范围来改善超级电容器的性能。虽然这些报告令人鼓舞，但对潜在的物理机制没有深入的了解。许多关键问题仍然没有答案：混合物中的离子性质如何影响离子的体积和孔内扩散率，并最终影响充电动力学？电化学性能如何随温度变化？如何匹配混合物中的孔隙大小和离子大小，以最大限度地存储能量？在充电过程中，碳结构/孔径与离子动力学之间的关系是什么？这些只是这一领域进一步发展所必需的一些关键问题。我们的项目通过结合电化学，原位核磁共振（NMR）测量和分子模拟来解决这些问题。我们将仔细研究电化学性能与性能的关系