Solvated Ions in Solid Electrodes: Alternative routes toward rechargeable batteries based on abundant elements

Storing large amounts of electrical energy is a major challenge for the forthcoming decades. Today, lithium-ion batteries (LIBs) are the best option for electric vehicles and grid storage but these rising markets put severe pressure on materials resources and supply chains. The principle of LIBs is based on solid electrodes separated by a liquid electrolyte between which Li ions are exchanged during charging and discharging. Efficient Li+ transport in the different phases and across the interfaces is essential for the performance. A fundamental difference between ion transport in solids and in solutions is that, in the latter case, the ion diffuses with a solvation shell. During charge transfer, this shell is stripped, i.e. a “naked” ion enters the solid electrode. Recently major efforts have been initiated to adopt the LIB concept to other working ions such as Na+, K+, Mg2+, Ca2+ or Al3+. This is motivated by the promise of lower cost thanks to their abundance and, in case of multivalent ions, also their higher charge density. With the exception of Na+, the progress is rather limited, however. Especially multivalent ions lead to severe lattice polarization and strong solvation shells frustrating ion mobility in solid electrodes and charge transfer.
This project aims at a radically different concept, i.e. instead of “naked” ions, solvated ions will be intercalated into the electrodes. Solvent co-intercalation is traditionally considered as highly detrimental. Latest results, however, question the generality of this argument. The SEED project will explore the concept of using solvated ions in solid electrodes for the reversible storage of a variety of ions. As the solvation shell acts as electrostatic shield and can be tuned in its composition, lattice polarization and charge transfer resistance can be minimized. Using this effect, the SEED project aims at reversible charge storage of multivalent ions in solids with properties far beyond current state-of-the art.

Adelhelm, Philipp Prof. Dr. (Details) (Physikalische und Theoretische Chemie (Physikal. Chemie d. Mat.))

Beteiligte Organisationseinheiten der HU

European Research Council (ERC) - Consolidator Grant

Projektstart: 06/2020
Projektende: 05/2025

Physikalische Chemie von Festkörpern und Oberflächen, Materialcharakterisierung

Zuletzt aktualisiert 2020-27-10 um 18:32