Cylindrical electrochemical cells and method of manufacture

Patent metadata

Field	Value
Publication number	US-2016351966-A1
Application number	US-201515115220-A
Country	US
Kind code	A1
Filing date	Jan 9, 2015
Priority date	Jan 28, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

An electrochemical storage cell may comprise first and second electrode sheets wound around a cylindrical core forming a jellyroll structure, the first and second electrode sheets each comprising uncoated conductive edges parallel to end faces of the jellyroll structure, and coated opposing surfaces between the uncoated conductive edges, first and second separator sheets mechanically and electrically separating the coated opposing surfaces of the first and second electrode sheets and mechanically and electrically separating the cylindrical core and the coated opposing surfaces of the first electrode sheet, and slotted cutouts from the uncoated conductive edges, the slotted cutouts angularly co-located relative to the cylindrical core upon forming the jellyroll structure.

First claim

1 . A method for an electrochemical storage cell, comprising:
winding a first electrode sheet and a second electrode sheet around a cylindrical core to form a jellyroll structure; the first electrode and the second electrode sheets each comprising uncoated conductive edges parallel to end faces of the jellyroll structure and coated opposing surfaces between the uncoated conductive edges; winding a first separator sheet and a second separator sheet around the cylindrical core wherein the first and the second separator sheets are positioned between the first and second electrode sheets to mechanically and electrically separate the coated opposing surfaces of the first electrode sheet and the second electrode sheet and to mechanically and electrically separate the cylindrical core and the coated opposing surfaces; and cutting out slots from the uncoated conductive edges of the first electrode and the second electrode sheets to form slotted cutouts, wherein the slotted cutouts are angularly co-located relative to the cylindrical core upon forming the jellyroll structure.

2 . The method of claim 1 , further comprising compressing angularly co-located portions of the uncoated conductive edges at end faces of the jellyroll structure to the cylindrical core to electrically connect the uncoated conductive edges to each other, wherein the angularly co-located portions of the uncoated conductive edges are adjacent to the slotted cutouts.

3 . The method of claim 2 , further comprising inserting a first and a second conductive core inserts into each end of the cylindrical core.

4 . The method of claim 3 , further comprising compressing the angularly co-located portions of the uncoated conductive edges at end faces of the jellyroll structure to the cylindrical core to electrically connect the uncoated conductive edges of the first electrode sheet to the first conductive core insert and to electrically connect the uncoated conductive edges of the second electrode sheet to the second conductive core insert.

5 . The method of claim 4 , further comprising welding the compressed angularly co-located portions of the uncoated conductive edges to the cylindrical core.

6 . The method of claim 5 , wherein the first and the second electrode sheets are electrically connected to the cylindrical core without welding conductive tabs to the first and second electrode sheets.

7 . An electrochemical storage cell, comprising:
a first electrode sheet and a second electrode sheet; the first and second electrode sheets wound around a cylindrical core forming a jellyroll structure; wherein the first and second electrode sheets each comprise uncoated edges parallel to end faces of the jellyroll structure and coated opposing surfaces between the uncoated conductive edges; a first separator sheet and a second separator sheet, wherein the first and second separator sheets mechanically and electrically separate the coated opposing surfaces of the first and second electrode sheets and mechanically and electrically separate the cylindrical core and the coated opposing surfaces of the first electrode sheet; and slotted cutouts from the uncoated conductive edges, the slotted cutouts angularly co-located relative to the cylindrical core upon forming the jellyroll structure.

8 . The electrochemical storage cell of claim 7 , further comprising compressing the angularly co-located portions of the uncoated conductive edges.

9 . The electrochemical storage cell of claim 8 , wherein the angularly co-located portions are electrically connected to each other.

10 . The electrochemical storage cell of claim 9 , wherein the angularly co-located portions are adjacent to the slotted cutouts.

11 . The electrochemical storage cell of claim 10 , wherein the cylindrical core comprises a pair of flat opposing sides, the pair of flat opposing sides forming a flattened ovular cross-section.

12 . The electrochemical storage cell of claim 11 , wherein the angularly co-located portions are electrically connected to the cylindrical core at the flat opposing sides.

13 . The electrochemical storage cell of claim 12 , wherein a length of the slotted cutouts forms an arc length corresponding to an angle less than 180° upon forming the jellyroll structure.

14 . The electrochemical storage cell of claim 13 , wherein a lengthwise end of the slotted cutout comprises a rounded shape.

15 . The electrochemical storage cell of claim 14 , wherein the slotted cutouts comprise a first and a second group of slotted cutouts, wherein the first and second group of slotted cutouts are angularly opposed at 180° relative to the cylindrical core.

16 . The electrochemical storage cell of claim 15 , further comprising a first and a second conductive core insert inserted into an end of the cylindrical core.

17 . The electrochemical storage cell of claim 16 , wherein a width of the coated opposing surfaces may be less than or equal to a width of the first and second separator sheets.

18 . A method for an electrochemical storage cell, comprising:
winding a first electrode sheet and a second electrode sheet around a cylindrical core to form a jellyroll structure; the first electrode and the second electrode sheets each comprising uncoated conductive edges parallel to end faces of the jellyroll structure and coated opposing surfaces between the uncoated conductive edges; winding a first separator sheet and a second separator sheet around the cylindrical core.

19 . The method of claim 18 wherein the first and the second separator sheets are positioned between the first and second electrode sheets to mechanically and electrically separate the coated opposing surfaces of the first electrode sheet and the second electrode sheet and to mechanically and electrically separate the cylindrical core and the coated opposing surfaces, the cell being an anode of a lithium-ion electrochemical storage cell.

20 . The method of claim 19 further comprising cutting out slots from the uncoated conductive edges of the first electrode and the second electrode sheets to form slotted cutouts, wherein the slotted cutouts are angularly co-located relative to the cylindrical core upon forming the jellyroll structure.

Assignees

• A123 Systems Llc

Inventors

• Batson David C
• Withers Rex
• Dawson James E

Classifications

• H01M10/0431

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title

• H01M10/0587 Primary

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M10/052

  Li-accumulators · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title