Novel In-Situ Electrolytes for Electrochemical Capacitors

• Applicants: Professor Dr. Andrea Balducci; Professor Dr. Lars Borchardt, Ph.D.
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Physical Chemistry of Solids and Surfaces, Material Characterisation ; Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 463487968

Electrical double layer capacitors (EDLCs) are nowadays considered among the most important energy storage devices. In these devices the energy is physically stored, through the formation of an electric double-layer at the interface between (polarized) electrodes and ions of the electrolyte Carbon-based materials are currently the state-ofthe- art electrode materials in EDLCs. These materials, however, are produced by means of multi-step syntheses associated with a high energy demand and an excessive accumulation of waste and byproducts. This is in sharp contrast with the core idea of sustainable energy production and storage. In this project we aim to design carbon syntheses in such a way that the formed by-products are not treated as waste products, but instead generate a salt suitable for the realization of EDLCs. Thus, the by-products contribute to the functionality of the desired final product and waste accumulating purification steps are by-passed completely. For that reason, we call this approach the ’in situ electrolyte‘ concept. Combining the expertise on porous carbon development of the Borchardt group with the expertise on electrolyte design of the Balducci group we target the following aspects: Firstly, understanding the underlying principles of in situ electrolyte concept by investigating different activation agents, super acids and precursor materials, secondly, to utilized this strategy for the realization of lithium and sodium-based electrolytes, thirdly advancing the concept to metal-ion capacitors and fourthly developing a 3rd generation in situ electrolyte concept, in which even the electrolyte solvent can be generated from the waste products of carbon syntheses.

• DFG Programme: Research Grants