Solid-state eutectic electrolyte via solvation regulation for voltage-elevated and deep-reversible Zn batteries.

Ling, Wei; Mo, Funian; Wu, Xiongwei; Zeng, Xianxiang; Xiong, Jian; Huang, Yan · Nat Commun · 2025

basic_science · Level V

Where this comes from

Abstract

Solid-state electrolytes have the great potential to achieve high-voltage and durable zinc-based batteries, but their effectiveness is limited by inferior ionic conductivity and large interfacial voltage polarization. Here, a nonflammable solid-state eutectic electrolyte is prepared in situ by cross-linking polymerization of ternary eutectic electrolyte with ethoxylated trimethylpropane triacrylate. Thanks to the intermolecular interaction among the deep eutectic solvents and polymer skeleton, the solid-state eutectic electrolyte possesses satisfactory room-temperature ionic conductivity of 3.94 × 10<sup>-3</sup> S cm<sup>-1</sup>. It enables the symmetric batteries with 80% Zn utilization operating stably at high current density of 8.0 mA cm<sup>-2</sup> for 1700 h, exceeding all non-aqueous and most aqueous zinc batteries. More importantly, due to solvation structure regulation, the solid-state eutectic electrolyte is found to elevate discharge voltage plateau to 2.1 V in Zn full batteries, and presents favorable rate performance and cyclic stability at 25 <math xmlns="http://www.w3.org/1998/Math/MathML"><mo>±</mo></math> 1 °C.