Electrode-composite separator assembly for lithium battery and lithium battery including the same

Patent metadata

Field	Value
Publication number	US-2017092915-A1
Application number	US-201615235302-A
Country	US
Kind code	A1
Filing date	Aug 12, 2016
Priority date	Sep 25, 2015
Publication date	Mar 30, 2017
Grant date	—

Abstract

An electrode-composite separator assembly for a lithium battery includes: an electrode; and a composite separator, wherein the composite separator includes: a copolymer including a first repeating unit represented by Formula 1, a second repeating unit represented by Formula 2, and a third repeating unit represented by Formula 3; at least one selected from an inorganic particle and an organic-inorganic particle; and at least one polymer selected from a fluorinated polymer and a heat-resistant polymer, wherein Formulas 1-3 are

Also a lithium battery including the electrode composite separator assembly.

First claim

What is claimed is:

1 . An electrode-composite separator assembly for a lithium battery, the electrode-composite separator assembly comprising:
an electrode; and a composite separator, wherein the composite separator comprises
a copolymer comprising a first repeating unit represented by Formula 1, a second repeating unit represented by Formula 2, and a third repeating unit represented by Formula 3,
at least one selected from an inorganic particle and an organic-inorganic particle, and
at least one polymer selected from a fluorinated polymer and a heat-resistant polymer;
wherein Formulas 1 to 3 are

wherein, in Formula 1,
R 1 is a hydrogen or a C1-C5 alkyl group, and
R 2 is a C2-C20 alkyl group,

wherein in Formula 2,
R 5 is a hydrogen or a C1-C5 alkyl group, and
R 6 is a methyl group, and

wherein in Formula 3,
R 3 is a hydrogen or a C1-C5 alkyl group, and
R 4 is a C1-C10 alkyl group.

2 . The electrode-composite separator assembly of claim 1 , wherein the first repeating unit represented by Formula 1 is at least one selected from an ethyl (meth)acrylate unit, propyl (meth)acrylate unit, a butyl (meth)acrylate unit, a pentyl meth)acrylate unit, a hexyl (meth)acrylate unit, and an octyl (meth)acrylate unit.

3 . The electrode-composite separator assembly of claim 1 , wherein the third repeating unit represented by Formula 3 is a vinyl acetate unit.

4 . The electrode-composite separator assembly of claim 1 , wherein an amount of the second repeating unit represented by Formula 2 in the copolymer is about 0.1 mole to about 1.5 moles, based on 1 mole of the first repeating unit represented by Formula 1.

5 . The electrode-composite separator assembly of claim 4 , wherein an amount of the third repeating unit represented by Formula 3 in the copolymer is about 0.1 mole to about 3.5 moles, based on 1 mole of the first repeating unit represented by Formula 1.

6 . The electrode-composite separator assembly of claim 1 , wherein an amount of the second repeating unit represented by Formula 2 is about 0.15 mole to about 0.5 mole, based on 1 mole of the first repeating unit represented by Formula 1.

7 . The electrode-composite separator assembly of claim 1 , wherein an amount of the third repeating unit represented by Formula 3 is about 0.5 mole to about 1.5 moles, based on 1 mole of the first repeating unit represented by Formula 1.

8 . The electrode-composite separator assembly of claim 1 , wherein the copolymer is a polymer represented by Formula 4a or Formula 4b:

wherein, in Formula 4a and Formula 4b, n, m, and p are mole fractions of the first to third repeating units, respectively, and are each independently about 0.01 to about 0.99, and
wherein a sum of n, m, and p is 1.

9 . The electrode-composite separator assembly of claim 1 , wherein the fluorinated polymer is at least one selected from polyvinylidene fluoride, a vinylidene fluoride-hexafluoropropylene copolymer, a vinylidene fluoride-trichloroethylene copolymer, and a vinylidene fluoride-chlorotrifluoroethylene copolymer.

10 . The electrode-composite separator assembly of claim 1 , wherein the fluorinated polymer comprises a high-viscosity, high-molecular weight fluorinated polymer having a viscosity of about 3,000 to about 5,000 centipoise when determined in acetone in an amount of 2 to 5 weight percent and a weight average molecular weight of about 1,000,000 to about 1,200,000 Daltons, and
a high-elasticity, low-viscosity fluorinated polymer having a viscosity of about 2,000 to about 4,000 centipoise when determined in acetone in an amount of 2 to 5 weight percent and a tensile modulus of about 1,300 to about 2,000 megaPascals.

11 . The electrode-composite separator assembly of claim 1 , wherein the heat-resistant polymer is at least one selected from a polyimide, polyethersulfone, polyvinylidene fluoride, polyamide, poly(meta-phenylene isophthalamide), polysulfone, polyetherketone, polyethylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, a polyphosphazene, poly (diphenoxy phosphazene), poly{bis[2-(2-methoxyethoxy)phosphazene]}, polyurethane copolymers, polyurethane, polyether urethane, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, polyester sulfone, polyetherimide, polycarbonate, polyphenylene sulfide, polyacrylate, and polytetrafluoroethylene.

12 . The electrode-composite separator assembly of claim 1 , wherein the at least one selected from an inorganic particle and an organic-inorganic particle is at least one selected from Al 2 O 3 , SiO 2 , B 2 O 3 , Ga 2 O 3 , TiO 2 , SnO 2 , BaTiO 3 , Pb(Zr a Ti 1−a )O 3 wherein 0≦a≦1, Pb 1−x La x Zr y O 3 wherein 0<x<1 and 0<y<1, Pb(Mg 3 Nb 2/3 ) 3 , PbTiO 3 , HfO 2 , SrTiO 3 , CeO 2 , MgO, NiO, CaO, ZnO, Y 2 O 3 , SiC, ZrO 2 , a borosilicate, BaSO 4 , a nanoclay, fumed silica, fumed alumina, graphite oxide, graphene oxide, and a metal-organic framework.

13 . The electrode-composite separator assembly of claim 1 , wherein an amount of the at least one selected from an inorganic particle and an organic-inorganic particle is about 500 parts to about 7,000 parts by weight, based on 100 parts by weight of a total weight of the copolymer comprising the first repeating unit represented by Formula 1, the second repeating unit represented by Formula 2, and the third repeating unit represented by Formula 3, and
the at least one selected from a fluorinated polymer and a heat-resistant polymer.

14 . The electrode-composite separator assembly of claim 1 , wherein a weight ratio of the copolymer comprising the first repeating unit represented by Formula 1, the second repeating unit represented by Formula 2, and the third repeating unit represented by Formula 3 to the at least one polymer selected from the fluorinated polymer and the heat-resistant polymer is about 1:9 to about 9:1.

15 . The electrode-composite separator assembly of claim 1 , wherein the composite separator has a thickness of about 5 micrometers to about 60 micrometers.

16 . The electrode-composite separator assembly of claim 1 , wherein the copolymer comprising the first repeating unit represented by Formula 1, the second repeating unit represented by Formula 2, and the third repeating unit represented by Formula 3 is a block copolymer.

17 . The electrode-composite separator assembly of claim 1 , wherein the composite separator comprises Al 2 O 3 , the copolymer represented by Formula 4a or Formula 4b, and polyvinylidene fluoride:

wherein, in Formula 4a and Formula 4b, n, m, and p are mole fractions of the first to third repeating units, respectively, and are each independently about 0.01 to about 0.99, and a sum of n, m, and p is 1.

18 . The electrode-composite separator assembly of claim 1 , wherein the electrode-composite separator assembly has a thermal shrinkage ratio of less than about 1% in both of a vertical direction and a horizontal direction after storage at 150° C. for 1 hour.

19 . The electrode-composite

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Ku Junhwan
• Shon Jeongkuk
• Song Minsang
• Ji Sangmin
• Choi Jaeman
• Park Myungkook
• Lee Byungmin
• Kim Hana

Classifications

• H01M10/0562

  Solid materials · CPC title

• H01M10/0525

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

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• C08L53/00

  Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers · CPC title

• H01M10/052 Primary

  Li-accumulators · CPC title