Enhanced Li-ion conductivity of strontium doped Li-excess garnet-type Li7+xLa3-xSrxZr2O12

The mechanism underlying the enhancement of the conductivity of Li7La3Zr2O12 (LLZO), an oxide-based solid electrolyte that contains excess Li, was experimentally investigated through subvalent cation substitution. We prepared Sr-substituted Li-rich LLZO with high conductivity of the order of 10(-4) S/cm by using a solid-state method. We investigated the mechanism underlying the conductivity enhancement via detailed structural analysis through Sr K-edge X-ray absorption near edge spectroscopy and X-ray diffraction and neutron powder diffraction analyses. The results suggested that the conductivity enhancement is due to the change in Li+ arrangement caused by the incorporation of excess Li into the LLZO lattice.

Automated summary

The conductivity enhancement of Li7La3Zr2O12 (LLZO), an oxide-based solid electrolyte with excess Li, was investigated experimentally through subvalent cation substitution. Sr-substituted Li-rich LLZO with high conductivity of the order of 10(-4) S/cm was prepared using a solid-state method. Detailed structural analysis through Sr K-edge X-ray absorption near edge spectroscopy, X-ray diffraction, and neutron powder diffraction analyses revealed that the conductivity enhancement is a result of the change in Li+ arrangement caused by the incorporation of excess Li into the LLZO lattice.