Boosting Ion Transport and Stability in Halide Solid Electrolytes via S and F Codoping
Journal article, 2025

Structural and compositional modification of solid-state electrolytes (SSEs) is a common approach to improve ionic conductivity and interfacial stability, yet the mechanisms remain unclear. Here, we studied Li2ZrCl6 (LZC) codoped with sulfur (S) and fluorine (F). X-ray and neutron diffraction with bond valence site energy (BVSE) simulations reveal that codopant-induced lattice distortion facilitates ion transport. The S/F codoped sample achieves a room-temperature ionic conductivity of 0.51 mS cm-1, twice that of pristine LZC (0.26 mS cm-1). Advanced characterizations further show that S and F participate in forming the solid electrolyte interphase (SEI), enhancing the electrode interfacial stability. As a result, solid-state batteries with the codoped SSE deliver capacity retentions of 97.1% at 0.1 C and 82.8% at 0.5 C. This study demonstrates the synergistic effects of structural modulation on ionic conduction and SEI formation, providing insights for designing high-performance SSEs.

Inorganic compounds

Halogens

Batteries

Solid electrolytes

Ionic conductivity

Author

Priya Ganesan

Helmholtz Association of German Research Centres

Karlsruhe Institute of Technology (KIT)

Ramon Zimmermanns

Karlsruhe Institute of Technology (KIT)

Helmholtz Association of German Research Centres

Guillaume Navallon

Helmholtz Association of German Research Centres

Karlsruhe Institute of Technology (KIT)

Yang Hu

Karlsruhe Institute of Technology (KIT)

Helmholtz Association of German Research Centres

Thomas Diemant

Helmholtz Association of German Research Centres

Karlsruhe Institute of Technology (KIT)

Gabriel J. Cuello

Institut Laue-Langevin

Ines Puente Orench

Institut Laue-Langevin

Blanka Detlefs

European Synchrotron Radiation Facility (ESRF)

Ritambhara Gond

Chalmers, Electrical Engineering, Electric Power Engineering

Alberto Varzi

Helmholtz Association of German Research Centres

Karlsruhe Institute of Technology (KIT)

Jianneng Liang

Karlsruhe Institute of Technology (KIT)

Helmholtz Association of German Research Centres

Maximilian Fichtner

Karlsruhe Institute of Technology (KIT)

Helmholtz Association of German Research Centres

ACS Energy Letters

23808195 (eISSN)

Vol. 10 11

Subject Categories (SSIF 2025)

Materials Chemistry

Inorganic Chemistry

DOI

10.1021/acsenergylett.5c02729

More information

Latest update

6/1/2026 2