Structural Relaxation and Nanodomain Dynamics in Highly Concentrated Electrolytes for Zinc Batteries

Published

June 17, 2024

Author(s)

Antonio Faraone, Fei Wang, Saya Takeuchi, Joseph Dura

Abstract

QuasiElastic Neutron Scattering (QENS) was employed to investigate the molecular-level dynamics of highly concentrated zinc-ion electrolytes (HCZE), a water-in-salt electrolyte enabling zinc batteries. Using heavy water, the coherent neutron scattering component of the spectra is enhanced, which probes the collective dynamics of electrolyte molecular structures, such as the anion-rich domains and nearest neighbor's cage. Thus, timescales of molecular diffusion and domain restructuring were obtained. Shear viscosity scales with the anion domain relaxation time. However, the molar conductivity is inversely proportional to the relaxation time of the aqueous domain. These results support the current understanding of ion transport in water-in-salt and water-in-bisalt electrolytes via water channels within anion-rich domains. Nevertheless, the HCZE conductivity is lower than expected by scaling the measured water domain structural relaxation to that of ideal low-concentration salt electrolytes. This finding shows that tortuosity and anion channel relaxation influence ion conduction.

Citation

Journal of Physical Chemistry C

Volume

128

Issue

29

Pub Type

Journals

Download Paper

https://doi.org/10.1021/acs.jpcc.4c00360

Local Download

Keywords

Batteries, Electrolytes, QENS

Citation

Faraone, A. , Wang, F. , Takeuchi, S. and Dura, J. (2024), Structural Relaxation and Nanodomain Dynamics in Highly Concentrated Electrolytes for Zinc Batteries, Journal of Physical Chemistry C, [online], https://doi.org/10.1021/acs.jpcc.4c00360, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957070 (Accessed December 13, 2024)