Journal article

Publication year: 2023

Journal: Small

Volume number: 20

Issue number: 15

ISSN: 1613-6810

eISSN: 1613-6829

Open access status: Hybrid

DOI Link: https://doi.org/10.1002/smll.202306832

Publisher: Wiley

Abstract: 

Superionic conductors are key components of solid-state batteries (SSBs). Multicomponent or high-entropy materials, offering a vast compositional space for tailoring properties, have recently attracted attention as novel solid electrolytes (SEs). However, the influence of synthetic parameters on ionic conductivity in compositionally complex SEs has not yet been investigated. Herein, the effect of cooling rate after high-temperature annealing on charge transport in the multicationic substituted lithium argyrodite Li6.5[P0.25Si0.25Ge0.25Sb0.25]S5I is reported. It is demonstrated that a room-temperature ionic conductivity of similar to 12 mS cm-1 can be achieved upon cooling at a moderate rate, superior to that of fast- and slow-cooled samples. To rationalize the findings, the material is probed using powder diffraction, nuclear magnetic resonance and X-ray photoelectron spectroscopy combined with electrochemical methods. In the case of moderate cooling rate, favorable structural (bulk) and compositional (surface) characteristics for lithium diffusion evolve. Li6.5[P0.25Si0.25Ge0.25Sb0.25]S5I is also electrochemically tested in pellet-type SSBs with a layered Ni-rich oxide cathode. Although delivering larger specific capacities than Li6PS5Cl-based cells at high current rates, the lower (electro)chemical stability of the high-entropy Li-ion conductor led to pronounced capacity fading. The research data indicate that subtle changes in bulk structure and surface composition strongly affect the electrical conductivity of high-entropy lithium argyrodites.

Harvard Citation style: Lin, J., Schaller, M., Cherkashinin, G., Indris, S., Du, J., Ritter, C., et al. (2023) Synthetic Tailoring of Ionic Conductivity in Multicationic Substituted, High-Entropy Lithium Argyrodite Solid Electrolytes, Small, 20(15), Article 2306832. https://doi.org/10.1002/smll.202306832

APA Citation style: Lin, J., Schaller, M., Cherkashinin, G., Indris, S., Du, J., Ritter, C., Kondrakov, A., Janek, J., Brezesinski, T., & Strauss, F. (2023). Synthetic Tailoring of Ionic Conductivity in Multicationic Substituted, High-Entropy Lithium Argyrodite Solid Electrolytes. Small. 20(15), Article 2306832. https://doi.org/10.1002/smll.202306832