Ceramic electrolyte material comprising a modified polycrystalline lithium metal phosphate

Patent metadata

Field	Value
Publication number	US-9905883-B2
Application number	US-201313852491-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 28, 2013
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

There is disclosed a polycrystalline lithium-ion conductive membrane for a lithium-air battery that comprises at least one surface, a polycrystalline lithium-ion conductive material comprising grain boundaries, and at least one modifying phase, wherein (a) the at least one modifying phase is incorporated into the grain boundaries to form a modified polycrystalline lithium-ion conductive material comprising modified grain boundaries, (b) the at least one modifying phase is incorporated into the at least one surface to form a modified surface, or both (a) and (b). Various lithium based batteries, including lithium ion, lithium-air, and lithium-water batteries are disclosed, as well as methods for modifying the polycrystalline lithium-ion conductive membrane to allow it to be used in such battery applications.

First claim

What is claimed is:

1. A polycrystalline lithium-ion conductive membrane comprising:
a polycrystalline lithium-ion conductive material comprising grain boundaries and a lithium metal phosphate comprising Li 1+x Al x Ti 2−x (PO 4 ) 3 where x>0, and at least one modifying phase comprising at least one oxide or phosphate of Ge, Ca, Y, Si, Mg, or Ga; and
wherein the at least one modifying phase is incorporated into the grain boundaries to form a modified polycrystalline lithium-ion conductive material comprising modified grain boundaries.

2. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the modified polycrystalline lithium-ion conductive material exhibits one of (c) a lower rate of etching by water than the polycrystalline lithium-ion conductive material, (d) a higher electrical conductivity than the polycrystalline lithium-ion conductive material, or both (c) and (d).

3. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the modified grain boundaries exhibit a lower rate of etching by water than the grain boundaries of the polycrystalline lithium-ion conductive material.

4. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the modified grain boundaries comprise Li 1+x Al x Ge y Ti 2−x−y (PO 4 ) 3 , where 0<x<0.6 and 0<y<2.

5. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the at least one modifying phase is incorporated into at least one surface of the polycrystalline lithium-ion conductive membrane to form a modified surface.

6. The polycrystalline lithium-ion conductive membrane of claim 5 , wherein the polycrystalline lithium-ion conductive membrane comprises two modified surfaces located on two opposite surfaces of said modified polycrystalline lithium-ion conductive membrane to form a structure having a modifying phase concentration gradient, wherein the concentration is higher at said opposite surfaces than at a center of the structure.

7. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the polycrystalline lithium-ion conductive material exhibits a density of at least 92% of a theoretical density of the polycrystalline lithium-ion conductive material.

8. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the polycrystalline lithium-ion conductive membrane has a thickness ranging from about 5 μm to about 500 μm.

9. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the polycrystalline lithium-ion conductive membrane is hermetic and diffusion of helium through the polycrystalline lithium-ion conductive membrane is less than about 10 −2 cm 3 /m 2 /day.

10. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the polycrystalline lithium-ion conductive membrane has a conductivity of greater than about 10 −4 S/cm.

11. A lithium battery comprising:
an anode comprising lithium;
a cathode; and
the polycrystalline lithium-ion conductive membrane of claim 1 located between the anode and cathode.

12. The lithium battery of claim 11 , wherein the lithium battery is selected from lithium ion batteries, lithium-air batteries, lithium-water batteries, and combinations thereof.

13. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the at least one modifying phase is incorporated into the grain boundaries near a surface of the polycrystalline lithium ion-conductive membrane and into the grain boundaries near a core of the polycrystalline lithium-ion conductive membrane.

14. The polycrystalline lithium-ion conductive membrane of claim 1 , wherein the at least one modifying phase is distributed in the grain boundaries throughout the polycrystalline lithium-ion conductive membrane.

15. A polycrystalline lithium-ion conductive membrane comprising:
a polycrystalline lithium-ion conductive material including grain boundaries and comprising Li 1+x Al x Ti 2−x (PO 4 ) 3 , where x>0; and
at least one modifying phase comprising Ge,
wherein (a) the at least one modifying phase is incorporated into the grain boundaries of the polycrystalline lithium-ion conductive material to form modified grain boundaries, (b) the at least one modifying phase is incorporated into at least one surface of the polycrystalline lithium-ion conductive membrane to form a modified surface, or both (a) and (b).

16. The polycrystalline lithium-ion conductive membrane of claim 15 , wherein the modified grain boundaries or modified surface comprise Li 1+x Al x Ge y Ti 2−x−y (PO 4 ) 3 , where 0<x<0.6 and 0<y<2.

17. A method for modifying the polycrystalline lithium-ion conductive membrane of claim 1 , the method comprising:
preparing a composition comprising the modifying phase or a precursor of the modifying phase;
forming a coated polycrystalline lithium-ion conductive membrane by applying the composition to at least one surface of the polycrystalline lithium-ion conductive membrane; and
annealing the coated polycrystalline lithium-ion conductive membrane to form the modified polycrystalline lithium-ion conductive membrane having (a) a modified surface comprising the modifying phase, (b) the modified grain boundaries comprising the modifying phase, or both (a) and (b).

18. The method of claim 17 , wherein the polycrystalline lithium-ion conductive material comprises lithium metal phosphate, and wherein the modifying phase comprises Ge.

19. The method of claim 17 , wherein the composition comprises GeO 2 particles made by a sol-gel process using a germanium isopropoxide precursor.

20. The method of claim 19 , wherein the GeO 2 particles have an average particle size ranging from 20-100 nm.

21. The method of claim 17 , wherein the step of applying the composition comprises dip-coating the composition onto the polycrystalline lithium-ion conductive membrane.

22. The method of claim 17 , further comprising drying the coated polycrystalline lithium-ion conductive membrane prior to the annealing.

23. The method of claim 17 , wherein the annealing is performed for a time ranging from about 0.5 to 12 hours in a furnace having a temperature ranging from about 700° C. to about 1000° C.

Assignees

• Corning Inc

Inventors

• Badding Michael Edward
• Brown Jacqueline Leslie
• Kester Lanrik Wayne
• Liu Xinyuan

Classifications

• H01M50/497

  Ionic conductivity · CPC title

• H01M50/434

  Ceramics · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title

• H01M2/145

  Electricity · mapped topic

• Y02T10/7011

  Cross-Sectional Technologies · mapped topic