Method of automated prismatic electrochemical cells production and method of the cell assembly and construction

• US 20060159999A1
• Filed: 03/18/2006
• Published: 07/20/2006
• Est. Priority Date: 07/23/2001
• Status: Abandoned Application

• Current Assignee: David Chua, Hsiu-Ping Lin, Joseph B. Kejha
• Original Assignee: David Chua, Hsiu-Ping Lin, Joseph B. Kejha
• Inventors: Chua, David, Kejha, Joseph B., Lin, Hsiu-Ping
• Application Number:
  US11/378,973
• Publication Number:
  US 20060159999A1
• Time in Patent Office: Days
• US Class Current: 429/254
• CPC Class Codes: H01G 11/28 arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 11/52 Separators
• CPC Class Codes: H01G 9/00 Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
• CPC Class Codes: H01G 9/02 Diaphragms; Separators
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• 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 10/058 Construction or manufacture
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• 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 4/622 being polymers
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/72 Grids
• CPC Class Codes: H01M 4/74 Meshes or woven material; Expanded metal
• CPC Class Codes: H01M 50/426 Fluorocarbon polymers
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 50/491 Porosity
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49114 : including adhesively bonding
• CPC Class Codes: Y10T 29/49115 : including coating or impregnating

Abstract

The present invention pertains to electrochemical devices having a thin micro porous polytetrafluoroethylene separator bonded to their porous electrodes without special treatment of the separator and without additional adhesive layers. Structures of superior high energy density and power density are disclosed herein, as well as the methods of their assembly and automated production.

Claims

1. A manufacturing method of prismatic single cell electrochemical device comprising the steps of:

providing a first dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a second dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a dry, untreated microporous polytetrafluoroethylene separator;

bonding said separator between said first electrode structure and said second electrode structure by said binders of said electrodes by applying heat and pressure and cooling said device;

and drying out said aprotic liquid.

7. A manufacturing method of prismatic electrochemical devices as described in claims 1, or 2, or 3, or 5, or 6, in which said aprotic liquid is selected from the group consisting of gamma-butyrolactone, ethylene carbonate, butylene carbonate, N-methylpyrrolidinone, glycols, and their mixtures.

8. A manufacturing method of lithium-ion based electrochemical devices as described in claims 1, or 2, or 3, or 5, or 6, in which said binders are selected from the group consisting of polyvinylidene fluoride homo polymers, polyvinylidene fluoride hexafluoropropylene copolymers, and their alloys.

9. A manufacturing method of lithium-ion based electrochemical devices as described in claims 1, or 2, or 3, or 5, or 6, in which said bonding step included a controlled temperature and pressure, which do not cause decomposition of said separator.

10. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said bonding step includes controlled temperature and said temperature is higher than the melting point of said binders'"'"' material.

11. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said bonding step includes controlled pressure and said pressure is produced by a compliant roller.

12. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said bonding step includes controlled pressure and said pressure is produced by a complaint plate.

13. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said coated active materials with a carbon and polymeric binder are dip-coated on said metal current collectors.

14. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said porous metal col1ectors are selected from expanded metal foils, metal micro grids, metal grids, and perforated metal foils.

15. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said device is a rechargeable lithium-ion cell.

16. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said device is an electrochemical capacitor.

17. A manufacturing method as described in claims 1, or 2, or 3, or 5, or 6, in which said device is a rechargeable aqueous battery cell.

2. A manufacturing method of prismatic bi-cell electrochemical device comprising the steps of:

providing a first dry porous electrode structure then soaked with an aprotic liquid and having an active material with carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a second dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a third dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a first dry, untreated, microporous polytetrafluoroethylene separator;

providing a second dry, untreated, microporous polytetrafluoroethylene separator;

bonding said first separator between said first electrode structure and said second electrode structure, and said second separator between said second electrode structure and said third electrode structure by said binders of said electrodes by applying heat and pressure and cooling said device;

and drying out said aprotic liquids.

3. A manufacturing method of prismatic bi-cell electrochemical device comprising the steps of:

providing a first dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

proving a second dry porous electrode structure then soaked with an aprotic liquid and having an active material with carbon and a polymeric binder coated on both sides of a solid metal foil current collector;

providing a third dry porous electrode structure then soaked with an aprotic liquid and having an active material with a carbon and a polymeric binder coated on both sides of a porous metal current collector;

providing a first dry, untreated, microporous polytetrafluoroethylene separator;

providing a second dry, untreated, microporous polytetrafluoroethylene separator;

bonding said first separator between said first electrode structures and said second electrode structure, and said second separator between said second electrode structures and said third electrode structure by said binders of said electrodes by applying heat and pressure and cooling said device;

and drying out said aprotic liquid.

4. A structure of prismatic electrochemical device comprising at least two prismatic porous electrodes having an active material with a carbon and a polymeric binder coated on both sides of porous metal current collectors of said electrodes;

and at least one prismatic microporous polytetrafluoroethylene separator bonded between said electrodes by said binders of said electrodes, and in which said binders and said separator are of dissimilar materials.

18. A structure of electrochemical devices as described in claim 4, in which said binders are selected from the group consisting of polyvinylidene fluoride homo polymers, polyvinylidene fluoride hexafluoropropylene copolymers, and their alloys.

19. A structure of electrochemical devices as described in claim 4, in which said coated active materials with a carbon and polymeric binder are dip-coated on said metal current collectors.

20. A structure of electrochemical devices as described in claim 4, in which said porous metal collectors are selected from expanded metal foils, metal micro grids, metal grids, and perforated metal foils.

21. A structure of electrochemical devices as described in claim 4, in which said device is a rechargeable lithium-ion cell.

22. A structure of electrochemical devices as described in claim 4, in which said device is an electrochemical capacitor.

23. A structure of electrochemical devices as described in claim 4, in which said device is a rechargeable aqueous battery cell.

5. A manufacturing method of automated production of a plurality of prismatic single cell electrochemical devices which comprises:

providing a first dry porous electrode length then soaked with an aprotic liquid having an active material with a carbon and a polymeric binder coated on a porous metal current collector with spaced terminal tabs thereon;

providing a second dry porous electrode length then soaked with an aprotic liquid having an active material with a carbon and a polymeric binder, coated on a porous metal current collector with spaced terminal tables thereon;

providing first dry, untreated, microporous polytetrafluoroethylene separator length;

cutting said first electrode and said second electrode lengths info leafs with said terminal tabs thereon;

assembling said first electrode leafs and said second electrode leafs onto said separator length in spaced and synchronized and overlying relation;

bonding together by heat and pressure and subsequent cooling said first electrode leafs, said separator length and said second electrode leafs into a layered assembly in overlying relation, with said first separator length between said first electrode leafs and said second electrode leafs, wherein said first separator length, said first electrode leafs and said second electrode leafs are assembled in synchronized relation to form single cells layered assembly length;

winding said layered assembly length onto a spool;

or cutting said assembly length between said leafs to form individual single cells; and

drying out said aprotic liquid, stacking, electrically connecting, activating and packaging said cells.

6. A manufacturing method of automated production of a plurality of prismatic bi-cell electrochemical devices which comprises;

providing a single cells'"'"' layered assembly length as described in claim 5;

providing a third dry porous electrode length then soaked with an aprotic liquid having an active material with a carbon and a polymeric binder coated on a porous metal current collector with spaced terminal tabs thereon;

providing second dry, untreated, microporous polytetrafluoroethylene separator length;

cutting said third electrode into leafs with said terminal tabs thereon;

assembling said single cells'"'"' layered assembly length and said second separator length in overlaying relation, and assembling said third electrode leafs onto said second separator length in spaced and synchronized and overlaying relation;

bonding together by heat and pressure said second electrode leafs, said second separator length and said third electrode leafs into a layered assembly in overlying relation, with said second separator length between said second electrode leafs and said third electrode leafs, wherein said second electrode leafs and said third electrode leafs, are assembled in synchronized relation to form bi-cell'"'"'s layered assembly length;

winding said layered assembly length onto a spool;

or cutting said assembly length between said leafs to form individual bi-cells; and

drying out said aprotic liquid, stacking, electrically connecting, activating and packaging said cells.