Decoding Structural Disorder, Synthesis Methods, and Short- and Long-Range Lithium-Ion Transport in Lithium Argyrodites (Li_6–xPS_5–xBr_1+x)

Chemistry of Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

By varying the bromine content and cooling method, we are able to induce site disorder in Li6–xPS5–xBr1+x (x = 0, 0.3, 0.5) system via two routes, allowing us disentangle impact of chemical composition on conductivity. Through solid-state nuclear magnetic resonance (NMR), can explore environment as well short-range lithium-ion dynamics compare these results obtained from neutron diffraction electrochemical impedance spectroscopy (EIS). We find that method has a profound effect 7Li 31P cannot be explained through 4d alone. The configurational entropy (Sconf) is used more complete descriptor structural linked distortions both phosphorus lithium environment. These correlated increased intercage movement T1 spin–lattice relaxation (SLR) NMR. Further analysis prefactors SLR NMR EIS allows obtain migrational (ΔSm). For movement, ΔSm correlates with Sconf, implying related distortion cages decrease distance. Comparison shows an increase translates into long-range straightforward manner for slow-cooled samples. However, quench-cooled samples, this correlation lost. Lattice softness phonon–ion interactions suggested play important role conduction which only becomes apparent when disentangled. This work by altering one synthesis step, relationship between site-occupancy-based descriptors (site or Sconf) changed profoundly. Furthermore, it seen same, changes length scale probed. Finally, challenges implicit assumption diffusivity automatically diffusivity.

Language: Английский

Optimizing Li‐Ion Transport in LaCl_3−xBr_x Solid Electrolytes Through Anion Mixing

EcoMat, Journal Year: 2025, Volume and Issue: 7(3)

Published: March 1, 2025

ABSTRACT Solid‐state batteries based on versatile halide solid electrolytes with outstanding ionic conductivity, electrode compatibility, and stability are attracting significant research attention. Recent experimental studies have illustrated the performance of LaCl 3 as a electrolyte capable conducting Li ions through its one‐dimensional channels that can be interconnected into three‐dimensional network creation La vacancies. In this work, we present composition optimization strategy for maximizing Li‐ion conductivity in 3− x Br density functional theory ab initio molecular dynamics simulations. Our simulations show 2.5 0.5 to remarkable 66 mS cm −1 at 300 K lowest activation energy 0.10 eV, followed by values 14 0.13 respectively. Both these compositions predicted easily synthesizable, large band gaps, likely interest given their transport properties. results highlight potential enhanced achieved anion mixing. image

Language: Английский

Disorder-Mediated Ionic Conductivity in Irreducible Solid Electrolytes

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: May 25, 2025

Solid-state batteries currently receive extensive attention due to their potential outperform lithium-ion in terms of energy density when featuring next-generation anodes such as lithium metal or silicon. However, most highly conducting solid electrolytes decompose at the low operating voltages leading irreversible loss and increased cell resistance. Such performance losses may be prevented by designing which are thermodynamically stable (anolytes). Here, we report on discovery a new family irreducible (i.e., fully reduced) mechanochemically dissolving nitride into Li2S antifluorite structure, yielding crystalline Li2+xS1-xNx phases reaching >0.2 mS cm-1 ambient temperature. Combining impedance spectroscopy experiments ab initio functional theory calculations clarify mechanism disordering sulfide ions anion sublattice boosts ionic conductivity factor 105 compared host structure. This advance is achieved through novel theoretical framework, leveraging percolation analysis with local-environment-specific activation energies widely applicable disordered ion conductors. The same methodology allows us rationalize how increasing nitrogen content antifluorite-like samples leads both lower conductivity-activation energy. These findings pave way understanding eliminating decomposition-induced anode side solid-state batteries.

Language: Английский