Multi layer electrolyte and cell using the same

• US 6,413,675 B1
• Filed: 07/15/1999
• Issued: 07/02/2002
• Est. Priority Date: 07/23/1998
• Status: Expired due to Fees

• Current Assignee: NEC Tokin Corporation (Yageo Corporation)
• Original Assignee: NEC Corporation
• Inventors: Nishiyama, Toshihiko, Fujiwara, Masaki, Harada, Gaku, Okada, Shinako
• Primary Examiner(s): KALAFUT, STEPHEN J
• Application Number:
  US09/353,384
• Time in Patent Office: 1,083 Days
• Field of Search: 429/105, 429/213, 429/300, 429/303, 429/306, 429/309, 429/313, 429/314, 429/315, 429/317, 296/233
• US Class Current: 429/300
• 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 10/058 Construction or manufacture
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 2300/0094 in the form of layered products, e.g. coatings
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/137 Electrodes based on electro-active polymers
• CPC Class Codes: H01M 4/139 Processes of manufacture
• CPC Class Codes: H01M 4/1399 of electrodes based on electro-active polymers
• CPC Class Codes: H01M 4/602 Polymers
• CPC Class Codes: H01M 4/622 being polymers
• CPC Class Codes: H01M 4/623 fluorinated polymers
• CPC Class Codes: H01M 6/187 Solid electrolyte characterised by the form
• CPC Class Codes: H01M 6/188 Processes of manufacture
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49112 including laminating of indefinite length material

Abstract

A multi layer electrolyte and a secondary cell using the multi layer electrolyte. The multi layer electrolyte comprises a solid electrolyte and other electrolyte such as gel electrolyte and/or electrolytic solution layer laminated on the solid electrolyte. The secondary cell using the multi layer electrolyte includes at least a positive electrode, a negative electrode and the multi layer electrolyte which comprises: a solid electrolyte layer; and at least one electrolyte layers selected from a gel electrolyte layer and an electrolytic solution layer and laminated on the solid electrolyte layer. By this structure, it is possible to use active material dissoluble in electrolytic solution as electrode active material and to realize a cell which can be quickly charged and discharged and which has superior capacity appearance rate and superior charge-discharge cycle characteristics.

Claims

1. A cell including at least a positive electrode, a negative electrode and an electrolyte, wherein said electrolyte is a multilayer electrolyte comprising:

first and second solid electrolyte layers disposed at the outermost sides of said electrolyte such that said first and second solid electrolyte layers are disposed contiguously to said positive electrode and said negative electrode; and

at least one electrolyte layer disposed between said first and second solid electrolyte layers, wherein the at least one electrolyte layer is selected from the group consisting of a gel electrolyte layer and an electrolytic solution layer.

2. The cell as set forth in claim 1, wherein at least one of said first and second solid electrolyte layers includes perfluorocarbonsulfonic acid.

3. The cell as set forth in claim 1, wherein at least one of said first and second solid electrolyte layers includes solid polymer electrolyte comprising a polymer having ether linkage, a polymer having ester linkage, a polymer having urethane linkage, a polymer having imide linkage, a polymer having siloxane linkage, or a polymer having phosphazene linkage.

4. The cell as set forth in claim 3, wherein said polymer having ether linkage has a polyoxyethylene backbone.

5. The cell as set forth in claim 3, wherein said polymer having ester linkage has a polyethylene succinate or a poly-β

-propionlactone.

6. The cell as set forth in claim 3, wherein said polymer having imide linkage is a polyethyleneimine.

7. The cell as set forth in claim 3, wherein said polymer having siloxane linkage has a polyether group.

8. The cell as set forth in claim 3, wherein said polymer having phosphazene linkage has a polyether group.

9. A cell including at least a positive electrode, a negative electrode and an electrolyte, wherein said electrolyte is a multilayer electrolyte comprising:

a solid electrolyte layer; and

at least one electrolyte layer selected from the group consisting of a gel electrolyte layer and an electrolytic solution layer and laminated on said solid electrolyte layer,

wherein at least one of said positive electrode and negative electrode includes active material which is dissoluble in electrolytic solution, and electrode or electrodes including active material which is dissoluble in electrolytic solution are adjacent said solid electrolyte layer but are not adjacent said gel electrolyte layer or said electrolytic solution layer.

10. The cell as set forth in claim 9, wherein each of said positive electrode and said negative electrode includes active material which is dissoluble in electrolytic solution, and wherein said multilayer electrolyte comprises:

a first solid electrolyte layer contiguous to said positive electrode;

at least one electrolyte layer laminated on said first solid electrolyte layer and selected from the group consisting of a gel electrolyte layer and an electrolytic solution layer; and

a second solid electrolyte layer laminated on said at least one electrolyte layer and contiguous to said negative electrode.

11. A cell as set forth in claim 9, wherein said electrode or electrodes including said active material which is dissoluble in electrolytic solution include solid electrolyte material and do not include gel electrolyte and electrolytic solution.

12. A cell as set forth in claim 9, wherein said positive electrode is prepared by using polyaniline as an active material, vapor deposition carbon as a conductivity assisting agent and polyvinylidene fluoride as a binder resin.

13. A cell as set forth in claim 9, wherein said positive electrode is prepared by using benzoquinone as an active material, vapor deposition carbon as a conductivity assisting agent and polyvinylidene fluoride as a binder resin.

14. A cell as set forth in claim 9, wherein said negative electrode is prepared by using polypyridine as an active material, vapor deposition carbon as a conductivity assisting agent and formic acid.

15. A cell as set forth in claim 9, wherein said positive electrode and said negative electrode are opposed via said multi layer electrolyte, and a collector is provided on each surface of said positive electrode and said negative electrode which do not contact said multi layer electrolyte.

16. A cell including at least a positive electrode, a negative electrode and an electrolyte, wherein:

at least one of said positive electrode and said negative electrode includes active material which is dissoluble in electrolytic solution;

said electrolyte is disposed between said positive electrode and said negative electrode and comprises a first electrolyte portion which includes solid electrolyte but which does not include gel electrolyte and electrolytic solution and a second electrolyte portion which includes gel electrolyte or electrolytic solution but which does not include solid electrolyte; and

said electrode or electrodes including active material which is dissoluble in electrolytic solution are adjacent said first electrolyte portion but are not adjacent said second electrolyte portion.

17. A method for manufacturing a cell including at least a positive electrode, a negative electrode and a multi layer electrolyte, said method comprises:

preparing said positive electrode and said negative electrode, wherein at least one of said positive electrode and said negative electrode includes active material which is soluble in electrolytic solution;

forming a solid electrolyte layer on said at least one electrode including active material which is soluble in electrolytic solution; and

opposing said positive electrode and said negative electrode via a separator including gel electrolyte or electrolytic solution so that said at least one of electrode including active material which is soluble in electrolytic solution opposes said separator including gel electrolyte or electrolytic solution via said solid electrolyte layer.

18. A method for manufacturing a cell as set forth in claim 17, wherein said preparing said positive electrode and said negative electrode includes:

fabricating slurry for said positive electrode and slurry for said negative electrode respectively from active material, conductivity assisting agent and binder;

fabricating a positive electrode film on a collector sheet by using said slurry for said positive electrode and fabricating a negative electrode film on a collector sheet by using said slurry for said negative electrode; and

cutting said collector sheet on which said positive electrode film is formed and said collector sheet on which said negative electrode film is formed into predetermined respective forms.

19. A method for manufacturing a cell as set forth in claim 17, wherein said forming a solid electrolyte layer on said at least one electrode including active material which is soluble in electrolytic solution comprises:

applying or impregnating perfluorocarbonsulfonic acid solution onto said electrode including active material which is soluble in electrolytic solution.

20. A method for manufacturing a cell as set forth in claim 17, wherein said opposing said positive electrode and said negative electrode via a separator including gel electrolyte or electrolytic solution comprises:

impregnating said gel electrolyte or said electrolytic solution into said separator and opposing said positive electrode and said negative electrode via said separator into which said gel electrolyte or electrolytic solution is impregnated.

21. A multilayer electrolyte comprising:

first and second solid electrolyte layers disposed at the outermost sides of said electrolyte; and

at least one electrolyte layer disposed between said first and second solid electrolyte layers, wherein the at least one electrolyte layer is selected from the group consisting of a gel electrolyte layer and an electrolytic solution layer.

22. The multilayer electrolyte as set forth in claim 21, wherein at least one of said first and second solid electrolyte layers includes perfluorocarbonsulfonic acid.

23. The multilayer electrolyte as set forth in claim 21, wherein at least one of said first and second solid electrolyte layers includes solid polymer electrolyte comprising a polymer having ether linkage, a polymer having ester linkage, a polymer having urethane linkage, a polymer having imide linkage, a polymer having siloxane linkage, or a polymer having phosphazene linkage.

24. A multilayer electrolyte as set forth in claim 23, wherein said polymer having ether linkage has a polyoxyethylene backbone.

25. A multilayer electrolyte as set forth in claim 23, wherein said polymer having ester linkage has a polyethylene succinate or a poly-β

-propionlactone.

26. A multilayer electrolyte as set forth in claim 23, wherein said polymer having imide linkage is a polyethyleneimine.

27. A multilayer electrolyte as set forth in claim 23, wherein said polymer having siloxane linkage has a polyether group.

28. A multilayer electrolyte as set forth in claim 23, wherein said polymer having phosphazene linkage has a polyether group.