Multilayer electrolyte cell, secondary battery comprising multilayer electrolyte cell and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-2018358652-A1
Application number	US-201715778125-A
Country	US
Kind code	A1
Filing date	Jul 7, 2017
Priority date	Jul 8, 2016
Publication date	Dec 13, 2018
Grant date	—

Abstract

The present invention relates to a multilayer electrolyte cell, a secondary battery including the multilayer electrolyte cell, and a manufacturing method thereof, and more particularly, to a multilayer electrolyte cell, in which electrolytes are configured in multiple layers by stacking polymer coating layers containing ceramic solid electrolytes and liquid electrolytes including an ionic liquid in a porous structure base, a secondary battery including the multilayer electrolyte cell, and a manufacturing method thereof.

First claim

1 . A multilayer electrolyte cell comprising:
a ceramic solid electrolyte; an anode located on one side of the ceramic solid electrolyte; a cathode located on the other side of the ceramic solid electrolyte; and a polymer coating layer formed between the ceramic solid electrolyte and the cathode, wherein in the ceramic solid electrolyte, an ionic liquid is included in a porous structure base.

2 . The multilayer electrolyte cell of claim 1 , wherein the porous structure base includes at least one inorganic ceramic selected from a group consisting of LiTiO 3 (LLTO), Li 1+x Al x Ti 2−x (PO 4 ) 3 (LTAP), Li 7 La 3 Zr 2 O 12 (LLZO), and Li 1+x Ti 2−x Al x Si y (PO 4 ) 3−y (where, 0<x<1, 0<y<1) and a Teflon-based binder

3 . The multilayer electrolyte cell of claim 2 , wherein the binder is polyvinylidene fluoride (PVDF).

4 . The multilayer electrolyte cell of claim 1 , wherein the ionic liquid includes at least one of 1-ethyl-3-methyl imidazolium, 1-butyl-3-methyl imidazolium, 1-butyl-1-methyl pyrrolidinium, 1-methyl-1-proply piperidinium, bis (trifluoromethylsulfonyl) imide (TFSI), and trifluoromethanesulfonate.

5 . The multilayer electrolyte cell of claim 1 , wherein the anode includes any one of xLi 2 MnP 3+(1−x) LiMO 2 , LiNi 0.5 Mn 1.5 O 4 , LiCoPO 4 , LiNiPO 4 , and Li 2 CoPO 4 F.

6 . The multilayer electrolyte cell of claim 1 , wherein the polymer coating layer includes any one or more of a high molecular polymer, a liquid electrolyte, a lithium salt, and an initiator.

7 . The multilayer electrolyte cell of claim 6 , wherein the high molecular polymer includes any one of ETPTA, PEO, PAN, PVdF and PMMA, the liquid electrolyte includes any one of an ether-based liquid electrolyte and a carbonate-based liquid electrolyte, the lithium salt includes any one or more of LiPFSi, LiPF 6 , LiClO 4 , LiAsF 6 , LiBF 4 , LiCF 3 SO 3 , and Li(CF 3 SO 2 )2N, and the initiator includes 2-hydroxy-2-methylpropiophenone.

8 . A secondary battery including a multilayer electrolyte cell of claim 1 .

9 . A manufacturing method of a secondary battery including a multilayer electrolyte cell, comprising:
(a) forming a polymer coating layer on a cathode; (b) stacking a ceramic solid electrolyte on an anode; and (c) stacking the ceramic solid electrolyte and the cathode so that the polymer coating layer is positioned between the ceramic solid electrolyte and the cathode.

10 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 9 , wherein step (a) includes (a1) preparing a polymer coating solution by mixing any one or more of a high molecular polymer, a liquid electrolyte, a lithium salt, and an initiator.

11 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 10 , wherein step (a1) includes
preparing an electrolyte mixture solution by mixing the high molecular polymer, the liquid electrolyte, and the lithium salt, and preparing a coating solution by mixing the initiator with the electrolyte mixture solution.

12 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 11 , wherein in step (a1), the high molecular polymer, the liquid electrolyte, and the lithium salt are mixed in a ratio of 40 to 60 wt %, 20 to 40 wt %, and 5 to 20 wt %, respectively.

13 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 11 , wherein in step (a1), the initiator is mixed in a weight ratio of 0.5 to 1.5% of a weight of the electrolyte mixture solution.

14 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 9 , wherein step (b) includes
(b1) preparing a porous structure base, (b2) preparing the ceramic solid electrolyte by impregnating an ionic liquid in the porous structure base, and (b3) stacking the ceramic solid electrolyte on the anode.

15 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 14 , wherein step (b1) includes
synthesizing ceramic powder by heat-treating a ceramic precursor, preparing a mixture solution by wet-mixing any one or more of the ceramic powder, a precursor, and a binder, generating mixture powder by spraying and drying the mixture solution, compressing the mixture powder, and forming the porous structure base by heat-treating the mixture powder.

16 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 15 , wherein in the synthesizing of the ceramic powder, the ceramic precursor is heat-treated at a temperature of 700 to 900° C.

17 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 15 , wherein in the preparing of the mixture solution, the mixture solution is mixed for 15 to 25 hours using any one of a ball mill, a rod mill, a vibrating mill, a centrifugal impact mill, a bead mill, and an attrition mill.

18 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 15 , wherein in the generating of the mixture powder, the mixture solution is sprayed and dried at a temperature of 100 to 200° C.

19 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 15 , wherein the compressing of the mixture powder includes
mixing and compressing the mixture powder and a powder precursor, and compressing the compressed mixed powder and powder precursor by cold isostatic pressing.

20 . The manufacturing method of a secondary battery including a multilayer electrolyte cell of claim 19 , wherein in the mixing and compressing of the mixture powder and the powder precursor, the mixture powder and the powder precursor are compressed at a pressure of 20 to 50 MPa and
wherein in the compressing of the compressed mixed powder and powder precursor by the cold isostatic pressing, the mixture powder and the powder precursor are compressed at a pressure of 1500 to 2500 kg/cm 2 .

21 . (canceled)

Assignees

• Lg Chemical Ltd
• Ulsan Nat Inst Science & Tech Unist

Inventors

• Lim Seongyoon
• Kwon Jiyoon
• Kim Seok Koo
• Hah Heojin
• Kim Youngsik
• Choi Hyunji
• Kim Jaekwang
• Hur Seongwoo

Classifications

• H01M2300/0074

  Ion conductive at high temperature · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M50/449

  having a layered structure · CPC title