Anionic Clustering in Zinc Salt–Concentrated Electrolyte Mixtures

Zinc shows great promise either as an alternative or additive to lithium ion batteries due to its low toxicity, low cost and high abundance. Yet if zinc ions are to be utilised in consumer battery materials, it is crucial to understand their solvation environment. This has important consequences for the electrical properties of the resulting electrolyte, and can influence both ion transport and the redox potential - key device properties. Here we propose to use neutron total scattering to determine the solvation structure of Zinc in two bis(trifluoromethanesulfonyl)imide (TFSI)-rich, technologically relevant environments: in a TFSI-based ionic liquid and in the lithium TFSI water-in-salt electrolyte. The zinc-TFSI solvation structure is contested in the literature, but by using total scattering and empirical potential structure refinement we will clarify our understanding of the solvation environment.