MICROPOROUS POLYOLEFIN FILM WITH THERMALLY STABLE POROUS LAYER AT HIGH TEMPERATURE

• US 20110064929A1
• Filed: 05/14/2009
• Published: 03/17/2011
• Est. Priority Date: 05/16/2008
• Status: Abandoned Application

• Current Assignee: SK Innovation Company Limited
• Original Assignee: SK Energy Corporation (SK Innovation Company Limited)
• Inventors: Rhee, Jang-weon, Kang, Gwigwon, Jung, Inhwa, Lee, Youngkeun
• Application Number:
  US12/992,621
• Publication Number:
  US 20110064929A1
• Time in Patent Office: Days
• US Class Current: 428/213
• CPC Class Codes: B32B 1/00 Layered products having a non-planar shape
• CPC Class Codes: B32B 2264/00 Composition or properties of particles which form a particulate layer or are present as additives
• CPC Class Codes: B32B 2264/0214 Particles made of materials belonging to B32B27/00
• CPC Class Codes: B32B 2264/0242 Vinyl halide, e.g. PVC, PVDC, PVF or PVDF (co)polymers
• CPC Class Codes: B32B 2264/0264 Polyamide particles
• CPC Class Codes: B32B 2264/0278 Polyester particles
• CPC Class Codes: B32B 2264/10 Inorganic particles
• CPC Class Codes: B32B 2264/102 Oxide or hydroxide
• CPC Class Codes: B32B 2264/104 Oxysalt, e.g. carbonate, sulfate, phosphate or nitrate particles
• CPC Class Codes: B32B 2264/12 Mixture of at least two particles made of different materials
• CPC Class Codes: B32B 2307/30 having particular thermal properties
• CPC Class Codes: B32B 2307/306 Resistant to heat
• CPC Class Codes: B32B 2307/581 Resistant to cut
• CPC Class Codes: B32B 2307/734 Dimensional stability
• CPC Class Codes: B32B 2457/10 Batteries
• CPC Class Codes: B32B 27/06 as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/045; next to a bituminous or tarry layer B32B11/046; next to a water setting substance layer B32B13/12; next to a metal layer B32B15/08; next to a glass layer B32B17/10; next to a layer formed of natural mineral fibres or particles B32B19/045; next to a wood layer B32B21/08; next to a cellulosic plastic layer B32B23/08; next to a natural or synthetic rubber layer B32B25/08
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 27/205 the fillers creating voids or cavities, e.g. by stretching
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 3/00 : Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
• CPC Class Codes: B32B 3/26 : characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids foam layer B32B5/18; layer of synthetic resin characterised by fillers that create voids or cavities B32B27/205; characterised by an apertured layer
• CPC Class Codes: B32B 7/10 : at least one layer having inter-reactive properties
• CPC Class Codes: H01M 10/0525 : Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 50/446 : Composite material consisting of a mixture of organic and inorganic materials
• CPC Class Codes: H01M 50/457 : comprising three or more layers
• CPC Class Codes: H01M 50/489 : Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24998 : Composite has more than two layers

Abstract

Provided is a microporous film for a secondary battery, and more particularly, to a microporous film for a secondary battery with excellent quality stability and heat resistance, the microporous film comprising a 3 layer microporous film wherein: an inner layer that includes polypropylene of 20-80 wt % having a melting temperature of 150° C. or higher and a filler of 80-20 wt % having a melting temperature of 140° C. or higher, wherein a gross content of the filler and polypropylene in the inner layer is 60 wt % or more, and both surface layers which include polyethylene, wherein at least one layer of the both surface layers includes polyethylene of 70 wt % or more.

Claims

1. A microporous film comprising a 3 layer microporous film wherein:

an inner layer includes polypropylene of 20-80 wt % having a melting temperature of 150°

C. or higher and a filler of 80-20 wt % having a melting temperature of 140°

C. or higher,

wherein a gross content of the filler and polypropylene in the inner layer is 60 wt % or more, and

both surface layers include polyethylene,

wherein at least one layer of the both surface layers includes polyethylene of 70 wt % or more.

2. The microporous film according to claim 1, wherein the inner layer includes polypropylene of 20-80 wt % having a melting temperature of 150°

C. or higher and a filler of 80-20 wt % having a melting temperature of 140°

C. or higher, the content of filler and polypropylene in the inner layer is 80 wt % or more, and both surface layers include polyethylene of 80 wt % or more, respectively.

3. The microporous film according to claim 2, wherein the inner layer includes polypropylene of 30-70 wt % having a melting temperature of 150°

C. or higher and a filler of 70-30 wt % having a melting temperature of 140°

C. or higher, and both surface layers are made of polyethylene.

4. The microporous film according to claim 1, wherein the thickness of the inner layer is 0.5 μ

m or more, the total thickness of the film is 7-50 μ

m, and the thickness ratio of the inner layer to the total thickness is 1%-50%.

5. The microporous film according to claim 4, wherein the puncture strength of the film is 0.12 N/μ

m or higher, the permeability is 1.0×

10<sup>−

5</sup> Darcy or higher, and the melt fracture temperature is 150°

C. or higher.

6. The microporous film according to claim 5, wherein the puncture strength of the film is 0.20 N/μ

m or higher, the permeability is 1.5×

10<sup>−

5</sup> Darcy or higher, and the melt fracture temperature is 160°

C. or higher.

8. The microporous film according to claim 1, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

13. The microporous film according to claim 2, wherein the thickness of the inner layer is 0.5 μ

m or more, the total thickness of the film is 7-50 μ

m, and the thickness ratio of the inner layer to the total thickness is 1%-50%.

14. The microporous film according to claim 3, wherein the thickness of the inner layer is 0.5 μ

m or more, the total thickness of the film is 7-50 μ

m, and the thickness ratio of the inner layer to the total thickness is 1%-50%.

15. The microporous film according to claim 2, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

16. The microporous film according to claim 3, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

17. The microporous film according to claim 4, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

18. The microporous film according to claim 5, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

19. The microporous film according to claim 6, wherein the filler having a melting temperature of 140°

C. or higher includes polyvinylidene fluoride, polymethylpentene, polyethylene terepthalate, polycarbonate, polyester, polyvinyl alcohol, polyacrylonitrile, polymethylene oxide, polyamide, or a heat resistant resin selected from a mixture thereof, or silicon dioxide (SiO₂), aluminum dioxide (Al₂O₃), calcium carbonate (CaCO₃), titanium dioxide (TiO₂), SiS₂, SiPO₄, MgO, ZnO, BaTiO₃, natural clay, organically modified clay, inorganic materials selected from a mixture thereof having an average particle size of 0.01 to 5 μ

m, or a mixture thereof.

7. (canceled)

9. (canceled)

10. (canceled)

11. (canceled)

12. (canceled)