Rechargeable lithium-ion battery cells and methods of making the same

• US 20020136957A1
• Filed: 01/23/2001
• Published: 09/26/2002
• Est. Priority Date: 01/23/2001
• Status: Active Grant

• Current Assignee: SKC Company Limited
• Original Assignee: SKC Company Limited
• Inventors: Zhang, Zhiwei, Park, Chi-Kyun, Sun, Lu Ying, Chai, Chul
• Granted Patent: US 6,547,839 B2
• Time in Patent Office: Days
• US Class Current: 429/246
• 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 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• CPC Class Codes: H01M 50/414 Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 50/461 with adhesive layers between electrodes and separators
• 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
• CPC Class Codes: Y10T 29/49108 Electric battery cell making
• CPC Class Codes: Y10T 29/49112 including laminating of indefinite length material
• CPC Class Codes: Y10T 29/49115 including coating or impregnating

Abstract

Lithium-ion electrochemical cells include an anode, a cathode and a separator between the anode and cathode, wherein at least one of the anode, cathode and separator includes a polysiloxane coating thereon. Most preferably, the polysiloxane coating is the polymerized reaction product of dimethyl siloxane and tetra(trimethylsiloxy) silane), and is present on the surface in an amount between about 0.05 to about 0.17 mg/cm². After being coated with the polysiloxane adhesive, the electrodes and separator can easily be attached one to another at ambient temperature by application of pressure using a hand roller or with a laminator, and then subsequently formed into a spiral or stacked structure for placement in a battery cell case.

Claims

1. A lithium-ion electrochemical cell comprising an anode, a cathode and a separator between said anode and cathode, wherein at least one surface of said anode, cathode and separator includes a coating comprising a polysiloxane adhesive.

2. The electrochemical cell of claim 1, wherein the polysiloxane adhesive includes a cross-linked polymerized reaction product of polysiloxane polymers, oligomers or monomers containing at least one hydroxy or alkoxy group.

3. The electrochemical cell as in claim 2, wherein an alkoxy group is present and is methoxy or ethoxy.

4. The electrochemical cell as in claim 2, wherein the polysiloxane is dimethyl siloxane or tetra(trimethylsiloxy) silane.

5. The electrochemical cell as in claim 1 or 2, further comprising a case for containing said anode, cathode and separator.

6. The electrochemical cell as in claim 5, further comprising an electrolyte contained in said case.

7. The electrochemical cell as in claim 1 or 2, wherein said anode, cathode and separator are in the form of a spiral structure.

8. The electrochemical cell as in claim 1 or 2, wherein said anode, cathode and separator are in the form of a stacked structure.

9. The electrochemical cell as in claim 1 or 2, wherein the polysiloxane coating is present in an amount between about 0.01 to about 0.4 mg/cm².

10. A method of making an electrochemical cell comprising the steps of (i) applying a polysiloxane adhesive onto a surface of at least one of an anode, a cathode and a separator, and thereafter (ii) stacking the anode, separator and anode in that order so as to laminate one to another.

11. The method of claim 10, wherein prior to said step (i), there is practiced the step of diluting the polysiloxane adhesive with an organic solvent.

12. The method of claim 11, wherein the organic solvent is at least one selected from the group consisting of toluene, xylene, acetone, tetrahydrofuran, butanone, and dioxane.

13. The method of claim 10, 11 or 12, wherein the polysiloxane is a silicon-containing prepolymer having at least one hydroxy, methoxy or ethoxy group.

14. The method of claim 13, wherein the polysiloxane is dimethyl siloxane or tetra(trimethylsiloxy) silane.

15. The method of claim 13, which further comprises allowing the prepolymer to polymerize in the presence of moisture.

16. The method of claim 11, wherein the organic solvent-diluted polysiloxane is applied onto the surface of at least one of the anode, cathode and separator by spray-coating, brushing or dip-coating.

17. The method of claim 10, 11 or 16, wherein the polysiloxane is coated onto said surface in an amount between about 0.01 to about 0.4 mg/cm².

18. The method of claim 13, wherein the polysiloxane prepolymer is present at a concentration of between about 0.1 to about 20 wt. %.