Abstract The performance of all‐solid‐state batteries (ASSBs) relies on the Li+transport and stability characteristics of solid electrolytes (SEs). Li3PS4is notable for its stability against lithium metal, yet its ionic conductivity remains a limiting factor. This study leverages local structural disorder via O substitution to achieve an ionic conductivity of 1.38 mS cm−1with an activation energy of 0.34 eV for Li3PS4−xOx(x = 0.31). Optimal O substitution transforms Li+transport from 2D to 3D pathways with increased ion mobility. Li3PS3.69O0.31exhibits improvements in the critical current density and stability against Li metal and retains its electrochemical stability window compared with Li3PS4. The practical implementation of Li3PS3.69O0.31in ASSBs half‐cells, particularly when coupled with TiS2as the cathode active material, demonstrates substantially enhanced capacity and rate performance. This work elucidates the utility of introducing local structural disorder to ameliorate SE properties and highlights the benefits of strategically combining the inherent strengths of sulfides and oxides via creating oxysulfide SEs.
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Transforming Li 3 PS 4 Via Halide Incorporation: a Path to Improved Ionic Conductivity and Stability in All‐Solid‐State Batteries
Abstract To enhance Li+transport in all‐solid‐state batteries (ASSBs), harnessing localized nanoscale disorder can be instrumental, especially in sulfide‐based solid electrolytes (SEs). In this investigation, the transformation of the model SE, Li3PS4, is delved into via the introduction of LiBr.31P nuclear magnetic resonance (NMR)unveils the emergence of a glassy PS43−network interspersed with Br−.6Li NMR corroborates swift Li+migration between PS43−and Br−, with increased Li+mobility indicated by NMR relaxation measurements. A more than fourfold enhancement in ionic conductivity is observed upon LiBr incorporation into Li3PS4. Moreover, a notable decrease in activation energy underscores the pivotal role of Br−incorporation within the anionic lattice, effectively reducing the energy barrier for ion conduction and transitioning Li+transport dimensionality from 2D to 3D. The compatibility of Li3PS4with Li metal is improved through LiBr incorporation, alongside an increase in critical current density from 0.34 to 0.50 mA cm−2, while preserving the electrochemical stability window. ASSBs with 3Li3PS4:LiBr as the SE showcase robust high‐rate and long‐term cycling performance. These findings collectively indicate the potential of lithium halide incorporation as a promising avenue to enhance the ionic conductivity and stability of SEs.
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- Award ID(s):
- 1847038
- PAR ID:
- 10470018
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 34
- Issue:
- 4
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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