EDLstruct - Effect of carbon electrodes porous structure and electrolyte properties on the formation and composition of the electrical double-layer

在多孔导电电极中形成双电层（EDL），例如，从活性炭（AC），代表了最有吸引力的策略之一，用于快速存储能量，因此，用于实现高功率能量存储设备。然而，考虑电解质边界具有平坦表面的现有EDL模型不能应用于微孔（<2nm）AC电极的情况。最近，原位技术提供了关于AC电极中的EDL性质的重要信息，然而它们是用独特的电解质和独特类型的多孔碳实现的。因此，EDLstruct项目的目标是实现具有各种具有明确多孔结构的碳的各种有机电解质，以研究：i）孔径和分子大小对极化下离子/溶剂比的影响，和ii）找到EDL结构与碳电极电化学性能衰减之间的相关性，具体取决于温度和电极电位。为了实现这一计划，需要在碳质材料（PUT组）和电解质（FSU Jena组）方面拥有强大的能力。此外，需要使用操作中技术（PUT）来监测电极极化过程中分子通量和EDL分解的影响。因此，将通过开展5个工作包来实现研究目标。FSU Jena将设计一些非水电解质（WP 1），而PUT将设计和表征具有不同结构特性的AC（WP 2）。两个小组将研究AC电极与所考虑的电解质组合的电化学性能。为了获得关于双层形成的信息，将通过PUT（WP 3）通过热程序解吸和操作中电阻抗测量法对极化电极进行事后分析。电极-电解质相互作用对双层的热稳定性的影响将在WP 4中通过FSU Jena（TGA/DSC）和PUT（电化学在线质谱）进行研究。实验结果将在WP 5中进行批判性讨论，并在国际会议上发表和发表。

The formation of an electrical double-layer (EDL) in a porous conductive electrode, e.g., from activated carbon (AC), represents one of the most appealing strategies for fast storage of energy and, consequently, for the realization of high power energy storage devices. However, the existing models of EDL which consider the electrolyte border with a flat surface cannot be applied to the case of microporous (<2 nm) AC electrodes. Recently, in-situ techniques have provided important information about the EDL properties in AC electrodes, yet they were implemented with a unique electrolyte and a unique type of porous carbon. Therefore, the objective of the EDLstruct project is to implement a variety of organic electrolytes with a variety of carbons of well-defined porous structure in order to study: i) the influence of pore size and molecules size on the ions/solvent ratio under polarization, and ii) to find correlations between the EDL structure and the decay of electrochemical performance of carbon electrodes depending on temperature and electrodes potential. In order to realize this program, strong competence in carbonaceous materials (PUT group) as well as in electrolytes (FSU Jena group) is needed. In addition, the use of in-operando techniques (PUT) is required to monitor the effects of molecular fluxes and EDL decomposition during polarization of electrodes. Hence, the research objectives will be reached by conducting 5 work packages. FSU Jena will design a number of non-aqueous electrolytes (WP1), while PUT will design and characterize ACs with different structural properties (WP2). The electrochemical performance of AC electrodes in combination with the considered electrolytes will be investigated by both groups. In order to acquire information about the double-layer formation, post-mortem analyses of polarized electrodes by thermoprogrammed desorption and in-operando electrical dilatometry will be carried out by PUT (WP3). The influence of the electrode-electrolyte interaction on the thermal stability of the double-layer will be investigated in WP4 by FSU Jena (TGA/DSC) and PUT (electrochemical on-line mass spectrometry). The experimental results will be critically discussed in WP5, giving rise to publications and presentations at international conferences.