Battery separator for Li-ion and/or Li-ion polymer battery

• US 20020102455A1
• Filed: 12/06/2000
• Published: 08/01/2002
• Est. Priority Date: 12/09/1999
• Status: Active Grant

• Current Assignee: NGK Spark PLUG Company Limited
• Original Assignee: NTK Powerdex, Inc.
• Inventors: Barlow, Geoffrey, Daroux, Mark L., Xing, Xuekun, Shokoohi, Frough K.
• Granted Patent: US 6,562,511 B2
• Time in Patent Office: Days
• US Class Current: 429/144
• CPC Class Codes: B32B 27/08 of synthetic resin
• 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 50/443 Particulate material
• CPC Class Codes: H01M 50/446 Composite material consisting of a mixture of organic and inorganic materials
• CPC Class Codes: H01M 50/449 having a layered structure
• CPC Class Codes: H01M 50/457 comprising three or more layers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49112 including laminating of indefinite length material

Abstract

A separator for a Li-ion polymer battery comprised of a plurality of separator layers that are laminated together. The plurality of separator layers including a first layer formed of a first separator material, and a second layer formed of a second separator material, wherein the second layer is compositionally and structurally different from the first layer.

Claims

1. A multi-layered separator for a Li-ion polymer battery, comprised of:

a plurality of separator layers that are laminated together, said plurality of separator layers including a first layer formed of a first separator material and a second layer formed of a second separator material, wherein the second layer is compositionally and structurally different from the first layer.

2. A multi-layered separator as defined in claim 1, wherein said first layer is adjacent to said second layer.

3. A multi-layered separator as defined in claim 2, wherein said separator includes two separator layers.

4. A multi-layered separator as defined in claim 1, wherein said separator includes a third layer formed of said first separator material, and said layers are arranged wherein said second layer is disposed between said first and third layer.

5. A multi-layered separator as defined in claim 4, wherein said first layer and said third layer have better adhesive properties than said second layer.

6. A multi-layered separator as defined in claim 1, wherein each of said separator layers is formed from a composition including a polymer, a filler and a plasticizer.

7. A multi-layered separator as defined in claim 6, wherein said polymer is polyvinylidene fluoride, said filler is silica and said plasticizer is dibutyl phthalate.

8. A multi-layered separator as defined in claim 6, wherein said first layer and said second layer are formed from the following:

about 33.4% by weight polyvinylidene fluoride,

about 44.4% by weight dibutyl phthalate and

about 22.2% by weight silica powder, and said second layer is comprised of the following;

about 30% by weight polyvinylidene fluoride,

about 35% by weight dibutyl phthalate and

about 35% by weight silica powder.

9. A Li-ion and/or Li-ion polymer cell, comprised of:

a cathode section;

an anode section; and

a multi-layered separator disposed between said anode section and said cathode section, said separator including a first layer formed of a first separator material and a second layer formed of a second separator material, wherein said first layer has different physical properties than said second layer.

10. A Li-ion and/or Li-ion polymer cell as defined in claim 9, wherein said separator includes a third layer formed of said first separator material, and said layers are arranged wherein said second layer is disposed between said first and third layer.

11. A Li-ion and/or Li-ion polymer cell as defined in claim 9, wherein said first layer is adjacent to said second layer.

12. A Li-ion and/or Li-ion polymer cell as defined in claim 9, wherein said separator includes two separator layers.

13. A Li-ion and/or Li-ion polymer cell as defined in claim 9, wherein each of said separator layers is formed from a composition including a polymer, a filler and a plasticizer.

14. A Li-ion and/or Li-ion polymer cell as defined in claim 13, wherein said polymer is polyvinylidene fluoride, said filler is silica and said plasticizer is dibutyl phthalate.

16. A method as defined in claim 15, wherein said multi-layered separator has two separator layers and said first separator layer is joined to said second separator layer.

17. A method as defined in claim 15, wherein said multi-layered separator has three layers and a third separator layer is disposed between said first separator layer and said second separator layer and is joined thereto.

15. A method of forming a Li-ion or Li-ion polymer battery having a multi-layered separator, comprising the steps of:

a) forming an anode section and a cathode section, said anode section having an anode layer adhered to an anode current collector layer and said cathode section having a cathode layer applied to a cathode current collector;

b) laminating a first separator layer formed of a first separator material to said anode layer of said anode section and laminating a second separator layer formed of a second separator material to said cathode layer of said cathode section, said second separator material being different from said first separator material;

c) laminating said anode section to said cathode section wherein said first separator layer and said second separator layer are disposed between said anode section and said cathode section.