Thin layer electrochemical cell with self-formed separator

• US 7,335,441 B2
• Filed: 03/23/2004
• Issued: 02/26/2008
• Est. Priority Date: 08/20/2001
• Status: Expired due to Fees

• Current Assignee: Power Paper Ltd. (Products To Go, Inc.)
• Original Assignee: Power Paper Ltd. (Products To Go, Inc.)
• Inventors: Nitzan, Zvi, Luski, Shalom, Shchori, Ehud
• Primary Examiner(s): Kalafut; Stephen J.
• Application Number:
  US10/806,192
• Publication Number:
  US 20040175624A1
• Time in Patent Office: 1,435 Days
• Field of Search: 429/124, 429/129, 429/144, 429/247, 429/253, 429/254, 429/255, 429/303, 429/306, 429/309, 429/317, 429/178, 296/231
• US Class Current: 429/124
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 2300/0002 Aqueous electrolytes
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 50/124 having a layered structure
• CPC Class Codes: H01M 50/1245 characterised by the external coating on the casing
• CPC Class Codes: H01M 50/403 Manufacturing processes of separators, membranes or diaphragms
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 6/12 with flat electrodes
• CPC Class Codes: H01M 6/181 with polymeric electrolytes
• CPC Class Codes: H01M 6/188 Processes of manufacture
• CPC Class Codes: H01M 6/22 Immobilising of electrolyte
• CPC Class Codes: H01M 6/40 Printed batteries , e.g. thin film batteries
• 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

Abstract

A method of forming an electrochemical cell is disclosed. The method comprises contacting a negative pole layer and a positive pole layer one with the other or with an optional layer interposed therebetween. The pole layers and the optional layer therebetween are selected so as to self-form an interfacial separator layer between the pole layers upon such contacting.

Claims

1. A method of forming an electrochemical cell, the method comprising

(a) printing a layer of positive pole powder onto a first substrate;

(b) printing a first layer of electrolyte on said positive pole layer, wherein said first electrolyte layer comprises a first self-forming separator layer ingredient;

(c) printing a layer of negative pole powder onto a second substrate;

(d) printing a second layer of electrolyte on said negative pole layer, wherein said second electrolyte layer comprises a second self-forming separator layer ingredient; and

(e) contacting said first substrate and said second substrate readily facilitating interaction between said self-forming separator layer ingredients in said positive pole layer and said negative pole layer to self form an interfacial separator layer between said negative pole layer and said positive pole layer.

2. The method of claim 1, further comprising the step of printing an ink prior to step (a) onto at least one of inner sides of first and second substrates, said ink being a current conductor.

3. A method of forming an electrochemical cell, the method comprising

(a) printing a layer of positive pole powder onto a first substrate;

(b) printing a first layer of electrolyte on said positive pole layer, wherein said first electrolyte layer comprises a first self-forming separator layer ingredient;

(c) printing a layer of negative pole powder onto a second substrate;

(d) printing a second layer of electrolyte on said negative pole layer, wherein said second electrolyte layer comprises a second self-forming separator layer ingredient; and

(e) contacting said first substrate and said second substrate with a thin layer interposed between said positive pole layer and said negative pole layer, wherein said thin layer comprises a third self-forming separator layer ingredient, readily facilitating interaction between said self-forming separator layer ingredients in said positive pole layer and said negative pole layer with said self-forming separator layer ingredient in said thin layer to self-form an interfacial separator layer between said negative pole layer and said positive pole layer.

4. The method of claim 3, wherein said positive pole layer and said negative pole layer are applied simultaneously onto said thin layer.

5. An electrochemical cell comprising a printed negative pole layer, a printed positive pole layer, a printed electrolyte, and a self-formed separator layer interposed between said negative pole layer and said positive pole layer.

6. The cell according to claim 5, wherein there is no separately added separator.

7. The cell according to claim 5, wherein said pole layers are selected such that said electrochemical cell is sufficiently deliquescent for keeping said pole layers generally wet and sufficiently electroactive for obtaining ionic conductivity between said pole layers.

8. The cell according to claim 5, wherein said self-formed separator layer comprises a polymer precipitate or a gel.

9. The cell according to claim 5, wherein said self-formed separator layer self-forms via a physical interaction.

10. The cell according to claim 9, wherein said physical interaction results in a formation of a polymer precipitate or a gel between said pole layers.

11. The cell according to claim 5, wherein said self-formed separator layer self-forms via a chemical reaction.

12. The cell according to claim 11, wherein said chemical reaction results in a formation of a polymer precipitate or a gel between said pole layers.

13. The cell according to claim 5, wherein said self-formed separator layer self-forms via a physical interaction between at least one polymer and at least one polymer precipitating agent.

14. The cell according to claim 5, wherein said self-formed separator layer self-forms via a physical interaction between at least one polymer and at least one electrostatic cross-linking agent.

15. The cell according to claim 5, wherein said self-formed separator layer self-forms via a chemical reaction between at least one polymerizable unit and at least one polymerization activator.

16. The cell according to claim 5, wherein at least one of said pole layers includes a material that is both deliquescent and electroactive.

17. The cell according to claim 16, wherein said material includes zinc chloride.

18. The cell according to claim 5, wherein said positive pole layer includes manganese dioxide powder and said negative pole layer includes zinc powder.

19. The cell according to claim 18, wherein said negative pole layer further includes carbon powder.

20. The cell according to claim 18, wherein said positive pole layer further includes carbon powder.

21. The cell according to claim 13, wherein said at least one polymer precipitating agent includes zinc chloride.

22. The cell according to claim 14, wherein said at least one polymer includes at least one anionically charged polymer.

23. The cell according to claim 22, wherein said at least one electrostatic cross-linking agent includes zinc ions.

24. The cell according to claim 22, wherein said at least one anionically charged polymer includes a polymer comprising a free carboxylic group.

25. The cell according to claim 14, wherein said at least one electrostatic cross-linking agent includes zinc chloride.

26. The cell according to claim 5, and further comprising at least one terminal in electrical contact with at least one of said pole layers.

27. An electrochemical cell comprising a printed negative pole layer, a printed positive pole layer, a printed electrolyte and a self-formed separator layer interposed between said negative pole layer and said positive pole layer, wherein said self-formed separator layer comprises a polymer precipitate or a gel formed by a deliquescent and/or adhesive polymer.

28. The electrochemical cell according to claim 27, wherein at least one controlled property of the formed separator layer is at least one of thickness, porosity, and adhesiveness.

29. An electrochemical cell comprising a printed negative pole layer, a printed positive pole layer, a printed electrolyte and a self-formed separator layer interposed between said negative pole layer and said positive pole layer, wherein said self-formed separator layer comprises a polymer precipitate or a gel formed via an interaction between at least one polymer and at least one polymer precipitating agent or at least one electrostatic cross-linking agent.

30. An electrochemical cell with controllable properties comprising:

a negative pole layer;

a positive pole layer;

an electrolyte; and

an integral and in-situ formed interfacial separator layer interposed therebetween, wherein at least one property of the formed separator layer is controlled by selection of electrolyte solution components in the negative and positive pole layers to facilitate controlling electrical and physical properties of the cell.