Oxide-based solid electrolyte and method of preparing the same

Patent metadata

Field	Value
Publication number	US-9490500-B2
Application number	US-201514608906-A
Country	US
Kind code	B2
Filing date	Jan 29, 2015
Priority date	May 28, 2014
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

An oxide-based solid electrolyte according to the present invention may be Li x La 3 M 2 O 12 and may have a cubic phase. The oxide-based solid electrolyte may further include first and second dopants. A method of preparing an oxide-based solid electrolyte according to the concept of the present invention may include mixing a lithium compound, a lanthanum compound, a metal compound, a first dopant precursor, and a second dopant precursor to prepare an intermediate, and crystallizing the intermediate to prepare Li x La 3 M 2 O 12 crystals having a cubic phase.

First claim

What is claimed is:

1. A method of preparing an oxide-based solid electrolyte, the method comprising:
mixing a lithium compound, a lanthanum compound, a metal compound, a first dopant precursor, and a second dopant precursor to prepare an intermediate; and
crystallizing the intermediate to prepare Li x La 3 M 2 O 12 crystals having a cubic phase (where x is 5 or 7, and M is any one selected from the group consisting of tantalum, niobium, and zirconium).

2. The method of claim 1 , wherein the first dopant precursor is a salt comprising a first dopant, and
the first dopant comprises any one selected form the group consisting of aluminum, germanium, silicon, gallium, indium, tin, and antimony.

3. The method of claim 2 , wherein the first dopant precursor is added to the intermediate so that the first dopant is present in a stoichiometric amount of 0.82 mol % to 1.64 mol % based on the Li x La 3 M 2 O 12 crystals.

4. The method of claim 1 , wherein the second dopant comprises any one selected from the group consisting of tantalum, niobium, and zirconium,
wherein the second dopant comprises a material that is different from a metal included in the metal compound.

5. The method of claim 4 , wherein the second dopant precursor is added to the intermediate so that the second dopant is present in a stoichiometric amount of 0.41 mol % to 0.82 mol % based on the Li x La 3 M 2 O 12 crystals.

6. The method of claim 1 , wherein the crystallizing of the intermediate comprises not forming Li x La 3 M 2 O 12 having a tetragonal phase and a material different from the Li x La 3 M 2 O 12 .

7. The method of claim 1 , wherein the crystallizing of the intermediate comprises heat treating the intermediate in a temperature range of 800° C. to 1,000° C. for 3 hours to 4 hours.

8. The method of claim 1 , wherein M is zirconium, and
the preparing of the intermediate comprises providing the lithium compound so that lithium included in the lithium compound is in an amount greater than 27.7 mol % and less than 30.9 mol % based on the Li x La 3 M 2 O 12 crystals.

9. The method of claim 1 , wherein M is tantalum, and
the preparing of the intermediate comprises providing the lithium compound so that lithium included in the lithium compound is in an amount greater than 26.8 mol % and less than 27.7 mol % based on the Li x La 3 M 2 O 12 crystals.

10. An oxide-based solid electrolyte comprising:
Li x La 3 M 2 O 12 crystals having a cubic phase;
a first dopant included in the Li x La 3 M 2 O 12 crystals; and
a second dopant included in the Li x La 3 M 2 O 12 crystals,
wherein the first dopant is included in an amount of 0.82 mol % to 1.64 mol % based on the Li x La 3 M 2 O 12 crystals, and
the second dopant is included in an amount of 0.41 mol % to 0.82 mol % based on the Li x La 3 M 2 O 12 crystals
(where x is 5 or 7, and M is any one selected from the group consisting of tantalum, niobium, and zirconium).

11. The oxide-based solid electrolyte of claim 10 , wherein the first dopant comprises any one selected form the group consisting of aluminum, germanium, silicon, gallium, indium, tin, and antimony.

12. The oxide-based solid electrolyte of claim 10 , wherein the second dopant comprises any one selected from the group consisting of tantalum, niobium, and zirconium,
wherein the second dopant comprises a material that is different from M of the Li x La 3 M 2 O 12 crystals.

Assignees

• Electronics & Telecommunications Res Inst

Inventors

• Shin Dong Ok
• Lee Young-Gi
• Kang Kunyoung
• Kim Kwang Man

Classifications

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• C04B2235/81

  Materials characterised by the absence of phases other than the main phase, i.e. single phase materials · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title

• C04B2235/3227

  Lanthanum oxide or oxide-forming salts thereof · CPC title