Composite polymer electrolyte (CPE) membranes for secondary solid state li-metal cells and process for the production thereof

Patent metadata

Field	Value
Publication number	US-11417907-B2
Application number	US-201716647085-A
Country	US
Kind code	B2
Filing date	Sep 14, 2017
Priority date	Sep 14, 2017
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

The present invention relates to a curable composition for preparing a composite polymer electrode, the curable composition containing:A) a Li-ion conducting solid electrolyte whose general composition has the formula:Li7+x−yMIIxMIII3−xMIV2−yO12whereinMII, MIII, MIV, MV are species of valence II to V; where 0≤x<3, preferably 0≤x≤2; and 0≤y<2 preferably 0≤y≤1;(B) a polymer;(C) a lithium salt;(D) an active plasticizer; and(E) a photoinitiator.The invention also relates to a process of preparing the curable composition, cured compositions and films derived from the curable composition, and solid-state lithium batteries whose solid electrolyte layer contains a cured composition or a cured film according to the invention.

First claim

The invention claimed is:

1. A curable composition for preparing a composite polymer electrolyte, the curable composition containing:
(A) a Li-ion conducting solid electrolyte;
(B) a polymer;
(C) a lithium salt;
(D) an active plasticizer; and
(E) a photoinitiator;
wherein the Li-ion conducting solid electrolyte (A) is lithium-lanthanum-zirconate (LLZO),
wherein the polymer (B) has a polymer chain of the type: polyether, polyacrylonitrile, polycarbonate, polyester, polylactone, poly(meth)acrylate ester; or polymer (B) is a block copolymer containing two or more of such polymer chain types as component blocks in polymer chains; or polymer (B) is a physical blend of two or more of such polymer chain types, and
wherein the active plasticizer (D) is one or more selected from the group consisting of: dimethoxytetraethylene glycol (TEGDME), diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, poly(ethylene glycol) dimethyl ether, and wherein the active plasticizer (D) has a water content below 10 ppm, and/or is obtained via a distillation process and/or via a drying step on molecular sieves and/or via a combination of both a distillation process and a drying step on molecular sieves to ensure its purity.

2. The curable composition according to claim 1 , wherein the polymer (B) is poly(ethylene oxide) (PEO) and/or poly(propylene oxide) (PPO).

3. The curable composition according to claim 1 , wherein the Li-ion salt (C) is one or more selected from the group consisting of: LiPF 6 , LiBF 4 , LiClO 4 , LiFSI, LiTFSI, LiBOB, LiAsF 6 , LiFAP, LiTriflate, LiDMSI, LiHPSI, LiBETI, LiDFOB, LiBFMB, LiBison, LiDCTA, LiTDI, LiPDI.

4. The curable composition according to claim 1 , wherein the active plasticizer (D) has a water content below 5 ppm, and/or is obtained via a distillation process and/or via a drying step on molecular sieves and/or via a combination of both a distillation process and a drying step on molecular sieves to ensure its purity.

5. The curable composition according to claim 1 , wherein the photoinitiator (E) has an aryl-CO— group, and is selected from the group consisting of 4-methylbenzophenone, benzophenone, chlorobenzophenone, fluorenones, xanthones, benzils, anthraquinones, terephthalophenones, an alpha-ketocoumarin, and a terephthalophenone.

6. The process of preparing a composition according to claim 1 comprising the mixing of components (A) to (E) at a temperature not exceeding 100° C.

7. The process of preparing a composition according to claim 1 comprising the mixing of components (A) to (E), with grinding, at a temperature not exceeding 100° C.

8. The process according to claim 6 , carried out a temperature not exceeding 90° C.

9. The process according to claim 6 , carried out a temperature not exceeding 80° C.

10. The process according to claim 6 , wherein no organic solvent is added to the mixture of components (A) to (E).

11. The process according to claim 6 wherein no Room Temperature Ionic Liquid (RTIL) is added to the mixture of components (A) to (E).

12. A film having a composition according to claim 1 .

13. A film according to claim 12 having a thickness of at least 0.5 μm and at most 500 μm.

14. A film according to claim 12 having a thickness of at least 1.0 μm and at most 200 μm.

15. A cured composition obtained by exposure of the curable composition according to claim 1 .

16. A cured film obtained by exposure to UV light of the film according to claim 12 .

17. A solid-state lithium battery comprising the following elements:
a positive electrode active material layer;
a solid electrolyte layer;
a negative electrode active material layer,
wherein the solid electrolyte layer contains a cured composition according to claim 15 , and the solid electrolyte layer is positioned between the positive electrode active material layer and negative electrode active material layer.

18. A solid-state lithium battery comprising the following elements:
a positive electrode active material layer;
a solid electrolyte layer;
a negative electrode active material layer,
wherein the solid electrolyte layer contains a cured composition according to claim 16 , and the solid electrolyte layer is positioned between the positive electrode active material layer and negative electrode active material layer.

19. The solid state lithium battery according to claim 17 , which is assembled in a monopolar or a bipolar configuration.

Assignees

• Toyota Motor Europe

Inventors

• Castro Laurent
• Barde Fanny
• Nair Jijeesh Ravi
• Falco Marisa
• Bella Federico
• Gerbaldi Claudio

Classifications

• H01M10/056 Primary

  characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes · CPC title

• H01M10/0562

  Solid materials · CPC title

• H01M2300/0077

  based on zirconium oxide · CPC title

• H01M2300/0091

  in the form of mixtures · CPC title

• H01M10/0565

  Polymeric materials, e.g. gel-type or solid-type · CPC title