电解质动力学对超级电容器充放电性能的影响

Efficiently storing the electrical energy generated by intermittent sources and the transition to an electric transportation era depends fundamentally on the development of high electrical energy storage devices. Electric double-layer capacitors (EDLCs) are promising devices for efficient storage of electrical energy. Using the room temperature ionic liquids (RTILs) as an electrolyte in the nano-pores of carbon electrode materials, the capacitance of the EDLCs is found to be increased significantly. However, it remains unknown why some RTILs offer better capacitance during fast charge-discharge process. In this project, we will study the diffusive dynamics of RTILs in the nanopores of carbon materials during the charging and discharging process using the state-of-the-art quasielastic neutron scattering (QENS) technique. The main focuses of the project are the following: (1) To find out a relation between the diffusion rate of the RTILs in the carbon nanopores and the performance of the EDLCs. (2) Establishing a correlation between molecular sizes to the pore size for the fast charge-discharge rate and understanding the charge storage mechanism of EDLCs in the molecule level. Our results will provide a scientific basis for the design of novel EDLCs with high energy storage and rate performance. In addition，we will educate young scientist in China of Neutron Scattering techniques.

高效地存储由风能、太阳能等间歇性能源转化来的电能，并将其应用于电动交通领域，关键在于开发出高效储电装置。双电层超级电容器正是一种非常有潜力的储电装置。使用受限于碳电极材料纳米孔中的室温离子液体作为电解质，双电层超级电容器的电容会显著增大。然而，目前尚不清楚为何采用某些离子液体的电容器在快速充放电过程中具有较高的电容。在本项目中，我们将采用最先进的准弹性中子散射技术(QENS)，研究充放电过程中碳电极材料纳米孔中室温离子液体分子的扩散动力学特性。本研究计划的重点如下：第一，找出碳纳米孔中室温离子液体的扩散速率与双电层超级电容器性能之间的关系；第二，确定在快速充放电过程中离子液体分子大小与纳米孔径尺寸之间的相关性，从分子层面揭示超级电容器的储电机理。我们的研究结果，将为设计新型高性能超级电容器提供科学依据，并为中国培养中子散射领域的人才。

高效地存储由风能、太阳能等间歇性能源转化来的电能，并将其应用于电动交通领域，关键在于开发出高效储电装置。双电层超级电容器正是一种非常有潜力的储电装置。使用受限于碳电极材料纳米孔中的室温离子液体作为电解质，双电层超级电容器的电容会显著增大。然而，目前尚不清楚为何采用某些离子液体的电容器在快速充放电过程中具有较高的电容。在本项目中，我们采用最先进的准弹性中子散射技术(QENS)，研究充放电过程中碳电极材料纳米孔中室温离子液体分子的扩散动力学特性。本项目深入系统地研究了如下关键课题：第一，找出碳纳米孔中室温离子液体的扩散速率与双电层超级电容器性能之间的关系；第二，确定在快速充放电过程中离子液体分子大小与纳米孔径尺寸之间的相关性，从分子层面揭示超级电容器的储电机理。我们的研究结果为设计新型高性能超级电容器提供了新的科学依据。