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DOE OSTI · 1860666

Impacts of vacancy-induced polarization and distortion on diffusion in Solid Electrolyte Li 3 OCl

Mehmedovic, Zerina·Wei, Vanessa·Grieder, Andrew·Shea, Patrick·Wood, Brandon C.·Adelstein, Nicole
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Abstract

We report that Lithium-rich oxychloride antiperovskites are promising solid electrolytes for enabling next-generation batteries. Here, we report a comprehensive study varying Li + concentrations in Li 3 OCl using ab initio molecular dynamics simulations. The simulations accurately capture the complex interactions between Li + vacancies (V$^'_{Li}$), the dominant mobile species in Li 3 OCl. The V$^'_{Li}$ polarize and distort the host lattice, inducing additional non-vacancy-mediated diffusion mechanisms and correlated diffusion events that reduce the activation energy barrier at concentrations as low as 1.5% V$^'_{Li}$. Our analyses of discretized diffusion events in both space and time illustrate the critical interplay between correlated dynamics, polarization and local distortion in promoting ionic conductivity in Li 3 OCl.

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25 ENERGY STORAGE36 MATERIALS SCIENCE37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICScorrelated motionsolid state batterysuperionic

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Mehmedovic, Zerina, Wei, Vanessa, Grieder, Andrew, Shea, Patrick, Wood, Brandon C., Adelstein, Nicole. 2021-10-11. Impacts of vacancy-induced polarization and distortion on diffusion in Solid Electrolyte Li 3 OCl. https://doi.org/10.1098/rsta.2019.0459

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