SEPARATOR FOR RECHARGEABLE LITHIUM BATTERY

• US 20140057155A1
• Filed: 05/31/2013
• Published: 02/27/2014
• Est. Priority Date: 08/23/2012
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Original Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Inventors: Kim, In, Kim, Hyung-Sik, Kim, Duk-Jung, Park, Zin
• Granted Patent: US 10,700,331 B2
• Time in Patent Office: Days
• US Class Current: 429/144
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 50/414 Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/42 Acrylic resins
• CPC Class Codes: H01M 50/426 Fluorocarbon polymers
• CPC Class Codes: H01M 50/449 having a layered structure
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A separator for a rechargeable lithium battery includes a backbone polymer, an ion conductive polymer coating the backbone polymer, and an electrolyte solution immersing the backbone polymer, wherein the backbone polymer and the ion conductive polymer are different from each other.

Claims

1. A separator for a rechargeable lithium battery comprising:

a backbone polymer;

an ion conductive polymer coating the backbone polymer; and

an electrolyte solution immersing the backbone polymer,

wherein the backbone polymer and the ion conductive polymer are different from each other.

2. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer comprises a polymer having high crystallinity.

3. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer comprises at least one selected from the group consisting of polyvinylidenefluoride (PVdF), polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), polyolefin, polyethyleneoxide (PEO), polypropyleneoxide (PPO), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), and polyvinylchloride (PVC).

4. The separator for a rechargeable lithium battery of claim 1, wherein the ion conductive polymer is a gel-type polymer.

5. The separator for a rechargeable lithium battery of claim 1, wherein the ion conductive polymer comprises at least one selected from the group consisting of a copolymer of polyvinylidenefluoride and hexafluoropropylene (PVdF-HFP), polyethylene (PE), polypropylene (PP), polyolefin, polyethyleneoxide (PEO), polypropyleneoxide (PPO), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), and polyvinylchloride (PVC).

6. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer comprises polyvinylidenefluoride (PVdF), and the ion conductive polymer comprises a copolymer of polyvinylidenefluoride and hexafluoropropylene (PVdF-HFP).

7. The separator for a rechargeable lithium battery of claim 4, wherein the PVdF-HFP comprises hexafluoropropylene (HFP) in an amount of about 2 to about 70 wt % based on the total weight of the PVdF-HFP.

8. The separator for a rechargeable lithium battery of claim 4, wherein the PVdF-HFP comprises the hexafluoropropylene (HFP) in an amount of about 5 to about 15 wt % based on the total weight of the PVdF-HFP.

9. The separator for a rechargeable lithium battery of claim 1, wherein the electrolyte solution comprises a lithium salt and a non-aqueous organic solvent.

10. The separator for a rechargeable lithium battery of claim 7, wherein the lithium salt comprises LiClO₄, and the non-aqueous organic solvent comprises a mixture of propylenecarbonate (PC) and ethylenecarbonate (EC).

11. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer is included in an amount of about 5 wt % to about 90 wt % based on the total weight of the separator.

12. The separator for a rechargeable lithium battery of claim 1, wherein the ion conductive polymer is included in an amount of about 5 wt % to about 90 wt % based on the total weight of the separator.

13. The separator for a rechargeable lithium battery of claim 1, wherein the electrolyte solution is included in an amount of about 5 wt % to about 90 wt % based on the total weight of the separator.

14. The separator for a rechargeable lithium battery of claim 1, wherein the ion conductive polymer and the electrolyte solution are included in a weight ratio of about 1:

9 to about 9;

1.

15. The separator for a rechargeable lithium battery of claim 1, wherein the ion conductive polymer and the electrolyte solution are included in a weight ratio of about 1:

2 to about 1;

9.

16. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer comprises a film.

17. The separator for a rechargeable lithium battery of claim 1, wherein the backbone polymer comprises at least one selected from the group consisting of polyvinylidenefluoride (PVdF), polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), polyolefin, polyethyleneoxide (PEO), polypropyleneoxide (PPO), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), and polyvinylchloride (PVC), and the ion conductive polymer comprises at least one selected from the group consisting of a copolymer of polyvinylidenefluoride and hexafluoropropylene (PVdF-HFP), polyethylene (PE), polypropylene (PP), polyolefin, polyethyleneoxide (PEO), polypropyleneoxide (PPO), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), and polyvinylchloride (PVC).