Ceramic material and preparation method therefor
The present invention provides a ceramic material capable of demonstrating compactness and Li ion conductivity to an extent that enables the use of the ceramic material as a solid-state electrolyte material for a lithium secondary battery, or the like. A ceramic material containing Li, La, Zr, Nb and/or Ta, as well as O and having a garnet-type or garnet-like crystal structure is used.
1. A sintered body comprising:
a ceramic material having a formula of Li 7-y La 3 Zr 2-y M y O 12 -zAl
wherein M represents Nb and/or Ta,
wherein y represents a total number of moles of Nb and Ta, and
wherein z represents 0.025-0.35 moles,
wherein a molar ratio (Nb+Ta)/La is 0.03 or greater to 0.20 or lower, and
wherein a molar ratio of La to Zr and M (La: (Zr+M)) is 3:2,
the sintered body having a garnet-type or garnet-like crystal structure, a Li ion conductivity of not less than 3.0*10 −5 S/cm, and a density of not less than 4.0 g/cm 3 .
2. The sintered body according to claim 1 , wherein the ceramic material includes a combination described in any of (a) to (c) below:
(a) a combination of Li, La, Zr, Nb, O, and Al,
(b) a combination of Li, La, Zr, Ta, O, and Al,
(c) a combination of Li, La, Zr, Nb, Ta, O and Al.
3. The sintered body according to claim 1 , which is a solid-state electrolyte material having Li ion conductivity.
4. An all-solid-state secondary battery using the ceramic material according to claim 1 .
5. An air secondary battery using the ceramic material according to claim 1 .
6. A lithium ion secondary battery using the ceramic material according to claim 1 .