In recent years, ternary halides Li3MX6 (M = Y, Er, In; X = Cl, Br, I) have garnered attention as solid electrolytes due to their wide electrochemical stability window and favorable roomtemperature conductivities. In this material class, the influences of iso-or aliovalent substitutions are so far rarely studied in-depth, despite this being a common tool for correlating structure and transport properties. In this work, we investigate the impact of Zr substitution on the structure and ionic conductivity of Li3InCl6 (Li3-xIn1-xZrxCl6 with 0 ≤ x ≤ 0.5) using a combination of neutron diffraction, nuclear magnetic resonance and impedance spectroscopy.Analysis of high-resolution diffraction data shows the presence of an additional tetrahedrally coordinated lithium position together with cation site-disorder, both of which have not been reported previously for Li3InCl6. This Li + position and cation disorder lead to the formation of a three-dimensional lithium ion diffusion channel, instead of the expected two-dimensional diffusion. Upon Zr 4+ substitution, the structure exhibits non-uniform volume changes along with an increasing number of vacancies, all of which lead to an increasing ionic conductivity in this series of solid solutions.

No abstract

Lithium metal batteries are gaining increasing attention due to their potential for significantly higher theoretical energy density than conventional lithium ion batteries. Here, we present a novel mechanochemical modification method for lithium metal anodes, involving roll-pressing the lithium metal foil in contact with ionic liquid-based solutions, enabling the formation of an artificial solid electrolyte interphase with favorable properties such as an improved lithium ion transport and, most importantly, the suppression of dendrite growth, allowing homogeneous electrodeposition/-dissolution using conventional and highly conductive room temperature alkyl carbonate-based electrolytes. As a result, stable cycling in symmetrical Li∥Li cells is achieved even at a high current density of 10 mA cm –2 . Furthermore, the rate capability and the capacity retention in NMC∥Li cells are significantly improved.

No abstract

Strong compositional influences are known to affect the ionic transport within the thio-LISICON family; however, a deeper understanding of the resulting structure–transport correlations has up until now been lacking. Employing a combination of high-resolution neutron diffraction, impedance spectroscopy, and nuclear magnetic resonance spectroscopy, together with bond valence site energy calculations and the maximum entropy method for determining the underlying Li+ scattering density distribution of a crystal structure, this work assesses the impact of the Li+ substructure and charge carrier density on the ionic transport within the Li4–x Ge1–x Sb x S4 substitution series. By incorporating Sb5+ into Li4GeS4, an anisometric expansion of the unit cell is observed. An additional Li+ position is found as soon as (SbS4)3– polyhedra are present, leading to a better local polyhedral connectivity and a higher disorder in the Li+ substructure. Here, we are able to relate structural disorder to an increase in configurational entropy, together with a 2 order-of-magnitude increase in ionic conductivity. This result reinforces the typically believed paradigm that structural disorder leads to improvements in ionic transport.