Lithium-stuffed garnet electrolytes with a reduced surface defect density and methods of making and using the same

Patent metadata

Field	Value
Publication number	US-11916200-B2
Application number	US-201716343361-A
Country	US
Kind code	B2
Filing date	Oct 19, 2017
Priority date	Oct 21, 2016
Publication date	Feb 27, 2024
Grant date	Feb 27, 2024

Abstract

The disclosure herein relates to rechargeable batteries and solid electrolytes therefore which include lithium-stuffed garnet oxides, for example, in a thin film, pellet, or monolith format wherein the density of defects at a surface or surfaces of the solid electrolyte is less than the density of defects in the bulk. In certain disclosed embodiments, the solid-state anolyte, electrolyte, and catholyte thin films, separators, and monoliths consist essentially of an oxide that conducts Li+ ions. In some examples, the disclosure herein presents new and useful solid electrolytes for solid-state or partially solid-state batteries. In some examples, the disclosure presents new lithium-stuffed garnet solid electrolytes and rechargeable batteries which include these electrolytes as separators between a cathode and a lithium metal anode.

First claim

The invention claimed is:

1. A method for reducing the number of defects on a single layer sintered lithium-stuffed garnet thin film, the method comprising the following steps in the following order:
providing a single layer sintered lithium-stuffed garnet thin film in a first step;
heating the top and/or bottom surfaces of the sintered lithium-stuffed garnet thin film to 700° C. to 1200° C. for 1 to 10 hours in an inert or reducing atmosphere in a second step;
wherein the inert or reducing atmosphere comprises a member selected from the group consisting of Ar, Ar/H 2 , N 2 , or combinations thereof; and
cooling the sintered lithium-stuffed garnet thin film in a third step in the inert or reducing atmosphere;
wherein the single layer sintered lithium-stuffed garnet thin film is not in contact with an unsintered lithium-stuffed garnet thin film.

2. The method of claim 1 , comprising heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film to at least 750° C.

3. The method of claim 1 , comprising heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film to at least 900° C.

4. The method of claim 1 , comprising heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film to at least 1000° C.

5. The method of claim 1 , comprising heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film to at least 1100° C.

6. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has top and bottom surfaces and a bulk therebetween, wherein the cooling in the third step is for a longest time which still provides for smaller grains on the top and/or bottom surface than in the bulk.

7. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has top and bottom surfaces and a bulk therebetween, wherein the cooling in the third step is for a longest time which still provides for a top and/or bottom surface which is denser than the bulk.

8. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has top and bottom surfaces and a bulk therebetween, wherein the cooling in the third step is for a longest time which still provides for a top and/or bottom surface which is less crystalline than the bulk.

9. The method of claim 1 , wherein the inert or reducing atmosphere is Ar, Ar/H 2 , or N 2 .

10. The method of claim 1 , wherein the heating in the second step is via an oven, a laser, a Rapid Thermal Processing instrument (RTP), infrared radiation, UV radiation, or a flash lamp.

11. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has the empirical formula Li a La b Zr c Al d Me″ e O f , wherein 5<a<8.5; 2<b<4; 0<c≤2.5; 0≤d≤2; 0≤e<2, and 10<f<13, and Me″ is a metal selected from Nb, Ga, or Ta.

12. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has the empirical formula Li x La y Zr z O t ·qAl 2 O 3 , wherein 4<x<10, 1<y<4, 1<z<3, 6<t<14, and 0≤q≤1.

13. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has top and bottom surfaces and a bulk therebetween, wherein after heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film, the top or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film has a lower surface defect density than does the bulk.

14. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has top and bottom surfaces and a bulk therebetween, wherein after heating the top and/or bottom surfaces of the single layer sintered lithium-stuffed garnet thin film, the top or bottom surface is more dense than the bulk.

15. The method of claim 1 , wherein the thickness between the top and bottom surfaces is between 1 μm and 100 μm.

16. The method of claim 1 , wherein prior to the heating the top or bottom surface of the sintered lithium-stuffed garnet thin film to 700° C. to 1200° C. in the second step, the sintered lithium-stuffed garnet thin film is comprised of a plurality of particles, wherein a particle size distribution of the particles has a d 90 of about 25-45 μm.

Assignees

• Quantumscape Battery Inc

Inventors

• Cao David
• Chao Cheng-Chieh
• Chen Zhebo
• Cheng Lei
• Donnelly Niall
• Hermann Wes
• Holme Tim
• Huang Tommy
• Kerman Kian
• Li Yang
• Maheshwari Harsh

Classifications

• H01M10/4235 Primary

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title

• C01G25/006

  Compounds containing zirconium, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• C04B35/44

  based on aluminates · CPC title

• C04B35/486 Primary

  Fine ceramics · CPC title

• C04B35/495

  based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates · CPC title