Journal article

Publication year: 2021

Pages: 7309-7315

Journal: ACS Applied Energy Materials

Volume number: 4

Issue number: 7

ISSN: 2574-0962

DOI Link: https://doi.org/10.1021/acsaem.1c01417

Publisher: American Chemical Society

Abstract: 
Superionic lithium argyrodites are attractive as solid electrolytes for all-solid-state batteries. These materials of composition Li6PS5X (X = Cl, Br, and I) exhibit structural disorder between the X-/S2- positions, with higher disorder realizing better Li+ transport. Further replacement of the sulfide by chloride anions (for the series Li7-xPS6-xClx) has been shown to increase the ionic conductivity. However, the underlying changes to the lithium substructure are still relatively unknown. Here, we explore a larger range of nominal halide compositions in this material from x = 0.25 to x = 1.5 and explore the changes with neutron diffraction and impedance spectroscopy. The replacement of S2- by Cl- causes a lowered average charge in the center of the prevalent Li+ "cages", which in turn causes weaker interactions with Li+ ions. Analysis of neutron diffraction data reveals that the increased Cl- content causes these clustered Li+ "cages" to become more interconnected, thereby increasing Li+ conductivity through the structure. This study explores the understanding of the fundamental structure-transport correlations in the argyrodites, specifically structural changes within the Li+ ion substructure upon changing the anionic charge distribution.

Harvard Citation style: Gautam, A., Ghidiu, M., Suard, E., Kraft, M. and Zeier, W. (2021) On the Lithium Distribution in Halide Superionic Argyrodites by Halide Incorporation in Li_7-xPS_6-xCl_x, ACS Applied Energy Materials, 4(7), pp. 7309-7315. https://doi.org/10.1021/acsaem.1c01417

APA Citation style: Gautam, A., Ghidiu, M., Suard, E., Kraft, M., & Zeier, W. (2021). On the Lithium Distribution in Halide Superionic Argyrodites by Halide Incorporation in Li_7-xPS_6-xCl_x. ACS Applied Energy Materials. 4(7), 7309-7315. https://doi.org/10.1021/acsaem.1c01417