Molecular Structure of Concentrated Electrolytes for a Highly Reversible Zinc-based Battery

We propose to use NIMROD to investigate the molecular structure of Highly Concentrated Zinc Electrolytes (HCZEs) as a function of the lithium salt content. HCZE are a new type of Water in BiSalt Electrolytes (WIBSE) which might allow the practical use of zinc anode batteries, improving their cycle life and energy density. HCZEs contain both Zn(TFSI)2 and Li(TFSI) [TFSI being bis(trifluoromethanesulfonyl)imide], this latter at very high concentrations. Ultimately, the effectiveness of HCZEs in improving the characteristics of zinc batteries is believed to be due to suppression of zinc hydroxide formation, through the depletion of water in the zinc ion solvation shell, the segregation of water molecules in the solvation shell of the lithium ions, and the disruption of the H-bond network of water. Taking advantage of hydrogen and lithium isotopic substitution methods, we aim to gather information on the water hydrogen bond network and the lithium solvent shell. Consequently, we expect to validate the proposed scenario for the zinc solvation shell. Of particular interest is the behaviour around the structural peak at Q~0.5 Å-1, signature of the anion long-range organization, which should be accessible on NIMROD. The information obtained will help validate the scenario proposed for the role played by HCZEs in zinc anode batteries and guide the design of even more appropriate electrolytes for zinc anode batteries.