Method for producing an electrochemical bundle of a lithium battery

Patent metadata

Field	Value
Publication number	US-2016226056-A1
Application number	US-201415025048-A
Country	US
Kind code	A1
Filing date	Sep 11, 2014
Priority date	Sep 25, 2013
Publication date	Aug 4, 2016
Grant date	—

Abstract

A method for producing an electrochemical bundle of a lithium battery, such as an Li-ion battery, with a view to electrically connecting same to the output terminals of the battery, wherein it includes the combination of two steps of folding an electrochemical bundle of a lithium battery which are carried out separately, i.e. a radial folding with plastic deformation and an axial compacting, which make it possible to obtain two separate areas on at least one, and preferably both, of the lateral ends of the bundle. The invention also concerns a method for producing an electrical connection part between the electrochemical bundle and one of the output terminals of the battery, and an associated current collector.

First claim

1 - 17 . (canceled)

18 . A process for producing an electrochemical bundle of a lithium accumulator, wherein the accumulator is a Li-ion accumulator, with a view to its electrical connection to the output terminals of the accumulator, including the following steps:
a/ providing an electrochemical bundle including at least one electrochemical cell consisting of a cathode and an anode on either side of a separator suitable for being impregnated with an electrolyte, the bundle having a shape that is elongate along a longitudinal axis X 1 , having, at one of its lateral ends, anode bands that are not coated and, at the other of its lateral ends, cathode bands that are not coated; b/ folding with plastic deformation, at least in a direction radial to the axis X 1 , a portion of the bands from the exterior to the interior of the electrochemical bundle, onto an area portion of at least one of the lateral ends so that at least two consecutive bands overlap in their folded portion and so that the folded portions that overlap form a substantially flat area; and c/ axial tamping along the axis of the bands of the electrochemical bundle, of at least the area portion of the lateral end that is not folded in step b/, the axial tamping being carried out repeatedly so as to obtain in the tamped and not folded area portion of the lateral end, a substantially flat plinth intended to be welded to a current collector.

19 . The process for producing an electrochemical bundle as claimed in claim 18 , the folding in step b/ and the axial tamping in step c/ being carried out at each of the lateral ends.

20 . The process for producing an electrochemical bundle as claimed in claim 18 , the thickness of the band portions folded onto a lateral end being smaller than 0.6 mm.

21 . The process for producing an electrochemical bundle as claimed in claim 18 , the axial tamping in step c/ being carried out on the entire area of a lateral end of the bundle.

22 . The process for producing an electrochemical bundle as claimed in claim 18 , the electrochemical bundle consisting of a single electrochemical cell being wound upon itself by spooling.

23 . The process for producing an electrochemical bundle as claimed in claim 22 , the folding in step b/ being carried out along at least one straight line passing through the center of the roll of the cell.

24 . The process for producing an electrochemical bundle as claimed in claim 22 , the folding in step b/ being carried out along at least one straight line not passing through the center of the roll of the cell.

25 . The process for producing an electrochemical bundle as claimed in claim 18 , in which a step d/ is carried out of welding together folded band portions of a given lateral end.

26 . The process for producing an electrochemical bundle as claimed in claim 25 , the welding step d/ being carried out between the step b/ of radial folding and the step c/ of axial tamping.

27 . The process for producing an electrochemical bundle as claimed in claim 25 , the welding step d/ consisting in obtaining a weld by ultrasonic, electric or laser welding.

28 . A process for producing an electrical connection portion between an electrochemical bundle of a lithium accumulator and one of the output terminals of the accumulator, including the following steps:
producing an electrochemical bundle according to the process as claimed in claim 18 ; welding together folded band portions of the electrochemical bundle of a given lateral end according to step d/ that is carried out of welding together folded band portions of a given lateral end; and welding the plinth obtained to a current collector itself intended to be electrically connected or coupled to an output terminal of the accumulator.

29 . The process for producing an electrical connection portion as claimed in claim 28 , in which the welding step d/ and the step of welding the plinth to a current collector are carried out simultaneously.

30 . The process for producing an electrical connection portion as claimed in claim 29 , prior to the simultaneous welding steps, a current collector is brought into contact against the plinth, the current collector including:
one or more contact ribs suitable for making contact against the plinth; and one or more apertures bounded by holding tabs suitable for holding in place the folded band portions of the electrochemical bundle.

31 . The process for producing an electrical connection portion as claimed in claim 29 , the simultaneous welding steps being carried out by laser welding.

32 . A current collector, especially intended to be employed in the process as claimed in claim 29 , including:
one or more contact ribs suitable for making contact against a plinth formed by the axially tamped and not folded band portions of a lateral end of an electrochemical bundle; and one or more apertures bounded by holding tabs suitable for holding in place the folded band portions of said lateral end of said electrochemical bundle.

33 . A lithium-ion (Li-ion) battery or accumulator including a casing including:
a bottom to which is welded one of the current collectors welded to the electrochemical bundle according to the process as claimed in claim 28 ; and a cover with a feedthrough forming an output terminal to which is welded the other of the current collectors welded to the electrochemical bundle according to the process as claimed in claim 28 .

34 . The Li-ion battery or accumulator as claimed in claim 33 , in which:
the material of the negative electrode(s) is chosen from the group including graphite, lithium, titanate oxide Li4TiO5O12; or based on silicon or based on lithium, or based on tin and alloys thereof; and the material of the positive electrode(s) is chosen from the group including lithium iron phosphate LiFePO4, lithium cobalt oxide LiCoO2, optionally substituted lithium manganese oxide LiMn2O4 or a material based on LiNixMnyCozO2 where x+y+z=1, or a material based on LiNixCoyAlzO2 where x+y+z=1, LiMn2O4, LiNiMnCoO2 or lithium nickel cobalt aluminum oxide LiNiCoAlO2.

Assignees

• Commissariat à l'Energie Atomique et aux Energies Alternatives
• Commissariat à l'Energie Atomique et aux Energies Alternatives

Inventors

• Masson Olivier
• Dewulf Frédéric
• Jost Pierre
• Leys Come-Emmanuel

Classifications

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/661

  Metal or alloys, e.g. alloy coatings (H01M4/669 take precedence) · CPC title

• H01M10/0431

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

• H01M10/052 Primary

  Li-accumulators · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title