Tailoring Chloride Solid Electrolytes for Reversible Redox

作者：Phillip Ridley, George Duong, Sarah L. Ko, Jin An Sam Oh, Grayson Deysher, Kent J. Griffith, Ying Shirley Meng · 发表于：Journal of the American Chemical Society · 年份：2025 · DOI：10.1021/jacs.4c14670 · 被引用次数：26 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Thermal Expansion and Ionic Conductivity

High Resolution Image Download MS PowerPoint Slide Solid-state electrolytes enable next-generation batteries that can theoretically deliver higher energy densities while improving device safety. However, when fabricating cathodes for all-solid-state batteries, solid-state electrolytes must be combined with the active materials in high weight fractions in order to achieve sufficient ionic percolation within the cathode composite. This requirement drastically hinders the practicality of solid-state batteries as the solid-state electrolyte is conventionally designed to be electrochemically inactive and is effectively electrochemical “dead weight”, lowering both the gravimetric and volumetric energy density of the cell. In this work, a well-known solid-state electrolyte, Na 2 ZrCl 6, is modified by aliovalent substitution of inactive Zr 4+ cations with redox-active M 5+ ( M = Nb or Ta) cations to create a series of Na 2– x M x Zr 1– x Cl 6 solid solutions that possess both high ionic conductivities and active sites for Na + storage. The Na + intercalation mechanisms of these solid-solution materials, in addition to those of the Na M Cl 6 end-member materials, are elucidated in this work. It was discovered that both the niobium- and tantalum-containing chlorides exhibit rather high electrochemical potentials (2.2–2.8 V vs Na 9 Sn 4 ), making them ideal catholytes to pair with commonly used oxide cathode materials like NaCrO 2 . This synergistic pairing leads to a cathode composite...