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-12237475-B2
Application number	US-202318348981-A
Country	US
Kind code	B2
Filing date	Jul 7, 2023
Priority date	Oct 21, 2016
Publication date	Feb 25, 2025
Grant date	Feb 25, 2025

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 contact with a current collector layer in a first step, wherein the single layer sintered lithium-stuffed garnet thin film comprises a top surface;
heating the single layer sintered lithium-stuffed garnet thin film to 700° C. to 1200° C. for 1 hour 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 single layer sintered lithium-stuffed garnet thin film in a third step in the inert or reducing atmosphere;
wherein the current collector layer comprises a metal selected from Al, Cu, Ni, steel, or alloys thereof, or combinations thereof.

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

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

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

5. The method of claim 1 , wherein the current collector comprises Ni.

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

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

8. The method of claim 1 , wherein the single layer sintered lithium-stuffed garnet thin film has a bulk, wherein the cooling in the third step is for a longest time which still provides for the top 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 r ·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 a bulk, wherein after heating the single layer sintered lithium-stuffed garnet thin film, the top surface 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 a bulk, wherein after heating the single layer sintered lithium-stuffed garnet thin film, the top surface is more dense than the bulk.

15. The method of claim 1 , wherein the thickness of the single layer sintered lithium-stuffed garnet thin film is between 1 μm and 100 μm.

16. The method of claim 1 , wherein prior to heating the single layer sintered lithium-stuffed garnet thin film to at least 400° C. in the second step, the single layer sintered lithium-stuffed garnet thin film is comprised of a plurality of particles, wherein a particle size distribution of the particles has a doo of about 25 μm-45 μm.

17. The method of claim 1 , comprising heating the single layer sintered lithium-stuffed garnet thin film to 700° C., 800° C., 900° C., 1000° C., 1100° C., or 1200° C., for 1 hour to 10 hours.

Assignees

• Quantumscape Battery Inc

Inventors

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

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/0447

  of complete cells or cells stacks · CPC title

• C01P2006/90

  Other properties not specified above · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2006/16

  Pore diameter · CPC title