Solid electrolyte, method for preparing same, and all-solid battery comprising same

Patent metadata

Field	Value
Publication number	US-11870033-B2
Application number	US-201916958426-A
Country	US
Kind code	B2
Filing date	Jan 11, 2019
Priority date	Jul 9, 2018
Publication date	Jan 9, 2024
Grant date	Jan 9, 2024

Abstract

A solid polymer electrolyte and a method of manufacturing the same are provided. More particularly, a solid polymer electrolyte having a high content of solids and exhibiting a flame retardant property and a method of manufacturing the same, wherein the solid polymer electrolyte includes a multifunctional acrylate-based polymer, a C2 to C10 polyalkylene oxide, a lithium salt and a non-aqueous solvent and wherein the multifunctional acrylate-based polymer is cross-linked with the polyalkylene oxide to form a semi-interpenetrating polymer network (semi-IPN).

First claim

The invention claimed is:

1. A solid polymer electrolyte comprising:
a multifunctional acrylate-based polymer;
a C2 to C10 polyalkylene oxide;
a lithium salt; and
a non-aqueous solvent, which is present in a solid state at room temperature and is homogeneously mixed within the solid polymer electrolyte through a melting process, and wherein the non-aqueous solvent comprises dimethyl sulfone,
wherein the multifunctional acrylate-based polymer and the polyalkylene oxide form a semi-interpenetrating polymer network (semi-IPN), and
wherein the multifunctional acrylate-based polymer, the C2 to C10 polyalkylene oxide, the lithium salt and the non-aqueous solvent together are present in an amount of more than 70% by weight of solids, based on a total weight of the electrolyte.

2. The solid polymer electrolyte of claim 1 , wherein the C2 to C10 polyalkylene oxide is present in an amount of from 0.1 parts by weight to 10 parts by weight, based on 100 parts by weight of the multifunctional acrylate-based polymer.

3. The solid polymer electrolyte of claim 2 , wherein the C2 to C10 polyalkylene oxide has a weight average molecular weight of from 1,000 g/mol to 1,500,000 g/mol.

4. The solid polymer electrolyte of claim 1 , wherein the multifunctional acrylate-based polymer comprises at least one polymerization unit derived from a monomer selected from trimethylolpropane ethoxylate triacrylate, trimethylolpropane propoxylate triacrylate, polyethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyester dimethacrylate, trimethylolpropane trimethacrylate, ethoxylated bisphenol A dimethacrylate, tetraethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexandiol diacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, pentaerythritol ethoxylate tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate.

5. The solid polymer electrolyte of claim 1 , wherein the C2 to C10 polyalkylene oxide comprises at least one of polyethylene oxide and polypropylene oxide.

6. The solid polymer electrolyte of claim 1 , wherein the lithium salt comprises at least one of LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiOH, LiOH H 2 O, LiBOB, LiClO 4 , LiN(C 2 F 5 SO 2 ) 2 , LiN(CF 3 SO 2 ) 2 , CF 3 SO 3 Li, LiC(CF 3 SO 2 ) 3 , LiC 4 BO 8 , LiTFSI, LiFSI, and LiClO 4 .

7. The solid polymer electrolyte of claim 1 , wherein the lithium salt is present in an amount of from 10 parts by weight to 50 parts by weight, based on 100 parts by weight of the electrolyte.

8. The solid polymer electrolyte of claim 1 , wherein the lithium salt has a concentration of from 0.5 M to 2.5 M relative to the non-aqueous solvent.

9. The solid polymer electrolyte of claim 1 , wherein the non-aqueous solvent further comprises at least one of sulfolane, and triethylene glycol dimethyl ether (TEGDME).

10. The solid polymer electrolyte of claim 1 , wherein the electrolyte has a thickness of from 10 μm to 300 μm.

11. The solid polymer electrolyte of claim 1 , wherein the electrolyte has an ionic conductivity at 25° C. of from 1.0×10 −6 S/cm to 5.0×10 −4 S/cm.

12. The solid polymer electrolyte of claim 1 , wherein the electrolyte further comprises at least one flame-retardant additive selected from a halogen-based flame retardant, a phosphorus-based flame retardant, a nitrogen-based flame retardant and an inorganic compound flame retardant.

13. The solid polymer electrolyte of claim 1 , wherein the electrolyte comprises more than 90% by weight of solids comprising the multifunctional acrylate-based polymer, the C2 to C10 polyalkylene oxide, the lithium salt and the non-aqueous solvent, based on a total weight of the electrolyte.

14. A method of manufacturing the electrolyte according to claim 1 comprising:
(1) mixing an electrolyte composition comprising a multifunctional acrylate-based polymer monomer, a C2 to C10 polyalkylene oxide, a lithium salt and a non-aqueous solvent;
(2) melting the electrolyte composition at 100° C. to 150° C. and
(3) photopolymerizing the melted electrolyte composition to obtain the electrolyte.

15. The method of claim 14 , wherein the method comprises further adding at least one photoinitiator selected from the group consisting of 2,2-dimethoxy-2-phenylacetonephenone (DMPA), 2-hydroxy-2-methylpropipphenone (HOMPP), lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), and IRGACURE 2959 (1-[4-(2-Hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one) at step (1).

16. An all-solid-state battery comprising the solid polymer electrolyte according to claim 1 and electrodes.

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Kim Daeil
• Chae Jonghyun

Classifications

• H01M10/0565 Primary

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

• C08F290/141

  Polyesters; Polycarbonates · CPC title

• H01M10/0525 Primary

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

• H01M50/411

  Organic material · CPC title

• H01M50/417

  Polyolefins · CPC title