| 摘要 |
Provided are a lithium-containing garnet crystal having high density and ionic conductivity, and an all-solid-state lithium ion secondary battery that uses this lithium-containing garnet crystal. The lithium-containing garnet crystal is represented by the chemical composition Li7-xLa3Zr2-xTaxO12 (0.2 ≤ x ≤ 1), has a relative density of 99% or higher, belongs to the cubic crystal system, and has a garnet type structure. This lithium-containing garnet crystal has a lithium ion conductivity of 1.0 × 10-3 S/cm or higher. In addition, this solid electrolyte material has a lattice constant a such that 1.28 nm ≤ a ≤ 1.30 nm, and lithium ions occupy 96 h sites in the crystal structure. The all-solid-state lithium ion secondary battery has a positive electrode, a negative electrode and a solid electrolyte, and the solid electrolyte is constituted from the lithium-containing garnet crystal. |
