Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/502—Interconnectors for connecting terminals of adjacent batteries; Interconnectors for connecting cells outside a battery casing
  • H01M50/514—Methods for interconnecting adjacent batteries or cells
  • H01M50/516—Methods for interconnecting adjacent batteries or cells by welding, soldering or brazing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
  • H01M50/471—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof
  • H01M50/474—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof characterised by their position inside the cells
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
  • B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/04—Construction or manufacture in general
  • H01M10/0413—Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/04—Construction or manufacture in general
  • H01M10/0436—Small-sized flat cells or batteries for portable equipment
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/058—Construction or manufacture
  • H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
  • H01M50/471—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof
  • H01M50/477—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof characterised by their shape
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
  • H01M50/471—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof
  • H01M50/48—Spacing elements inside cells other than separators, membranes or diaphragms; Manufacturing processes thereof characterised by the material
  • H01M50/483—Inorganic material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/531—Electrode connections inside a battery casing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/531—Electrode connections inside a battery casing
  • H01M50/533—Electrode connections inside a battery casing characterised by the shape of the leads or tabs
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/531—Electrode connections inside a battery casing
  • H01M50/536—Electrode connections inside a battery casing characterised by the method of fixing the leads to the electrodes, e.g. by welding
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/531—Electrode connections inside a battery casing
  • H01M50/54—Connection of several leads or tabs of plate-like electrode stacks, e.g. electrode pole straps or bridges
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
  • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

• TITLE Electrochemical harness, battery cell and associated manufacturing processes
• the present invention relates, according to a first aspect, to an electrochemical bundle comprising a plurality of stacks stacked along a stacking direction, each stack comprising an electrode of first polarity, an electrode of second polarity, a first separator and a second separator, the electrode of second polarity being interposed between the first separator and the second separator, the second separator being interposed between the electrode of first polarity and the electrode of second polarity, the electrode of first polarity comprising a planar collector, a connection tab electric and a layer comprising an active material covering at least one face of the collector, the electrical connection tab being devoid of the layer comprising the active material, and protruding from an upper edge of the collector, the electrical connection tab s extending between the upper edge of the collector and an upper edge in a vertical direction substantially perpendicular to the stacking direction.
• This invention is particularly applicable to electrochemical battery cells that use negative electrodes based on lithium titanium oxide (LTO) or titanium niobium oxide (TNO), graphite, silicon, lithium metal or an alloy, or any other active material which does not present a risk of depositing lithium and therefore of forming dendrites due to its high operating potential.
• This invention is also applicable for electrochemical battery cells which use positive electrodes based on lithiated oxide of nickel, manganese and cobalt (NMC), a lithiated oxide of nickel, cobalt and aluminum (NCA), a lithiated iron phosphate (LFP) or a mixed lithium iron manganese phosphate (LMFP).
• Figure 1 illustrates an example of a prior art battery cell 100 comprising such an electrochemical bundle 102.
• the electrochemical bundle 102 is connected in its upper part to the terminals 104 of the prismatic element via a weld on metal connectors 106.
• the cover which closes the battery cell is likely to exert a stress on the connection, and consequently, on the tabs 108 of the electrodes. As shown in Figure 1, they therefore fold towards the stack and generally adopt a curved configuration.
• the tongues 108 of the positive electrodes which are not coated with the layer comprising the active material are arranged near the upper edges of the collectors of the negative electrodes.
• the tabs 108 of the positive electrodes which are not coated with the layer comprising the active material are arranged near the upper edges of the collectors of the positive electrodes.
• the separator placed between each pair of opposite positive and negative electrodes is interposed between each tongue of a positive electrode and the upper edge of the opposite negative electrode, and between each tongue of a negative electrode and the upper edge of the positive electrode.
• the bending zone of the tabs occupies a large space in the upper part of the cup, limiting the dimensions of the electrodes inside the cup and consequently the capacity of the battery cell. .
• An object of the invention is therefore to provide an electrochemical bundle for a battery element which is reliable during its use and which makes it possible to optimize the electrical capacity and the compactness of the battery element.
• the subject of the invention is an electrochemical bundle, as defined above, in which the electrochemical bundle further comprises a first metal separation device interposed between each pair of adjacent electrical connection tabs in the direction of stacking , the first separation device being fixed to at least one of said electrical connection tabs, the first separation device extending, between each pair of adjacent electrical connection tabs, between a lower edge and an upper edge in the vertical direction, the upper edges of the first separation device substantially flush with the upper edges of the electrical connection tongues of the first polarity electrodes.
• the upper edges of the electrical connection tabs and the upper edges of the first separation device define a surface suitable for soldering an electrical connector.
• the first separation device makes it possible to densify and stiffen the upper part of the electrical connection tabs, facilitating the step of welding the electrical connector.
• the electrochemical bundle may include one or more of the following characteristics, taken individually or in any technically possible combination:
• the height of the electrical connection tab taken relative to the upper edge of the collector is less than 5 mm, preferably between 1 mm and 5 mm;
• each pair of adjacent electrical connection tabs delimit between them a gap receiving the first separation device, the width of the first separation device between the adjacent electrical connection tabs, taken along the stacking direction, being at least equal to 60 % of gap width;
• the lower edges of the first separation device are arranged apart, in the vertical direction, from the upper edges of the collectors of the first polarity electrodes of the plurality of stacks;
• the first separation device is welded to the electrical connection tab by at least one weld
• the weld is a laser weld or an ultrasonic weld
• each electrical connection tab extends between a first side edge and a second side edge in a horizontal direction substantially perpendicular to the vertical direction and the stacking direction, the first separation device being a continuous metal strip successively surrounding the first side edge of an electrical connection tab and the second side edge of an adjacent electrical connection tab;
• the first electrical connection device comprises a plurality of metal separation members, distinct from each other, interposed respectively between each pair of adjacent electrical connection tabs, each separation member extending between a lower edge and an upper edge according to direction vertical, the upper edges of the first separating device being formed by the upper edges of the various separating members.
• the invention also relates to a battery element comprising:
• At least one first electrical connector welded to the upper edges of the electrical connection tongues of the first polarity electrodes and to the upper edges of the first separation device.
• the invention also relates to a method of manufacturing an electrochemical bundle as described above, the method comprising:
• the method comprises the following characteristic: the fixing of the first separation device to the electrical connection tongue is carried out by welding.
• the invention also relates to a method for manufacturing a battery element comprising the following steps:
• Figure 1 is a perspective view of a prior art battery cell
• Figure 2 is a perspective view of a battery cell according to a first embodiment of the invention
• Figure 3 is a partial schematic views in perspective and in section of the negative electrodes of the electrochemical bundle of the battery element of Figure 2
• Figure 5 is a partial schematic view of a method of manufacturing an electrochemical bundle of the battery element of Figure 2
• Figure 6 is a perspective view of the negative electrodes of an electrochemical bundle according to a second embodiment of the invention.
• Figure 2 illustrates a battery cell 10 according to a first embodiment of the invention.
• the battery is an electrochemical battery as usually used in railway vehicles or in aircraft. Other fields of battery application are possible, such as motor vehicles, energy storage systems or electric mobility.
• the battery element 10 comprises a casing or cup (not shown) defining an interior volume and at least one electrochemical bundle 12 disposed in the interior volume of the cup.
• the battery cell comprises a cover 14 closing the interior volume of the bucket, a first polarity terminal 16, here negative, a second polarity terminal 17, here positive, a first electrical connector 18 and a second electrical connector 19 electrically connecting the electrochemical bundle 12 respectively to the first polarity terminal 16 and to the second polarity terminal 17, both accessible on the cover 14.
• the bucket has a bottom wall, and a side wall projecting from the bottom wall to delimit the interior volume.
• the cup is preferably of parallelepiped shape, in particular rectangular parallelepiped.
• the interior volume of the bucket opens through an access opening which opens upwards, when the bottom wall is placed on a horizontal collector.
• orientations are defined with reference to the bucket placed on a horizontal surface, with its bottom wall in contact with the horizontal surface.
• the terms “up”, “down”, “upper”, “lower”, “horizontal”, “vertical” extend relative to this orientation.
• the lid 14 is intended to be fixed on the bucket to close the interior volume upwards.
• Each electrochemical beam 12 is received in the interior volume.
• the volume occupied by the electrochemical bundle(s) 12 is greater than 70% of the interior volume.
• each electrochemical bundle 12 comprises a plurality of successive stacks 20 stacked in a stacking direction E, and at least one first metallic separation device 22.
• Each stack 20 comprises a first polarity electrode 24, in particular a negative electrode, a second polarity electrode 26, in particular a positive electrode, a first separator 28 and a second separator 29.
• the second polarity electrode 26 is interposed between the first separator 28 and the second separator 29.
• the second separator 29 is interposed between the first polarity electrode 24 and the second polarity electrode 26.
• Each electrochemical bundle 12 is also bathed in an electrolyte, present in the interior volume to impregnate the electrodes 24, 26, the first separator 28 and the second separator 29.
• the first polarity electrode 24, here the negative electrode comprises a flat collector 30, a layer 32 comprising an active material covering the collector 30 and an electrical connection tab 34 projecting towards the top, in a vertical direction V substantially perpendicular to the stacking direction E, relative to the collector 30 to allow connection to the first electrical connector 18.
• the second polarity electrode 26, here the positive electrode also comprises a flat collector 36, a layer 38 comprising an active material covering the collector 36 and an electrical connection tongue projecting upwards with respect to to the collector 36 to allow connection to the second electrical connector 19.
• each electrode 24, 26 is preferably metallic, for example copper or aluminum depending on the polarity of the electrode 24, 26. It constitutes a current collector. It is for example formed of a strip, in particular of a thin strip having a thickness of less than 20 ⁇ m.
• the collector 30 of each of the first polarity electrodes 24 has for example a substantially polygonal outline, in particular a rectangular outline. It extends in the vertical direction V, between a lower edge 42 and an upper edge 44, substantially perpendicular to the stacking direction E. It extends in a horizontal direction H, substantially perpendicular to the vertical direction V and to the stacking direction E, between a first side edge 46 and a second side edge (not represented). First side edge 46 is located closer to tab 34 than second side edge 48.
• the upper edge 44 extends on either side of the tongue 34, which projects from the upper edge 44.
• the height in the vertical direction V at which the upper edge 44 extends with respect to the lower edge 42 is preferably identical on either side of the tab 34.
• the tongue 34 is preferably made in one piece with the manifold 30. The tongue 34 is thus obtained during the production of the manifold 30.
• the tab 34 here has a polygonal contour, for example rectangle or square.
• the tongue 34 extends in the horizontal direction H between a first lateral edge 50 connected to the upper edge 44 of the manifold 30, and a second lateral edge 52, also connected to the upper edge 44 of the manifold 30.
• the tongue 34 extends also between the lower edge 42 of the manifold 30 and an upper edge 54 in the vertical direction V, connecting the first side edge 50 and the second side edge 52.
• the upper edge 54 defines at least one substantially planar surface.
• the height of the tab 34 taken relative to the upper edge 44 of the manifold 30 is preferably less than 3 mm, preferably between 1 mm and 5 mm.
• the tongue 34 defines a first face 56 and a second face 58 substantially parallel to the first face 56.
• the second face 58 is arranged opposite the first face 56.
• the first face 56 and the second face 58 each extend in planes substantially perpendicular to the stacking direction E.
• the tabs 34 are arranged next to each other in the stacking direction E, the first face 56 of a tab 34 being arranged opposite the second face 58 of an adjacent tab 34 along the stacking direction E.
• the tabs 34 are advantageously all identical to each other.
• Each tongue 34 is spaced from an adjacent tongue 34, in the stacking direction E, by a gap 60.
• the gap 60 is defined between the first face 56 of a tongue 34 and the second face 58 of the tongue 34 adjacent.
• the width of the gap 60 taken along the stacking direction E is equal to the sum of the widths of the second polarity electrode 26, here positive, of the first separator 28, of the second separator 29, and of two layers 32 of material comprising the active material covering one face of each of the collectors 30 of two adjacent first polarity electrodes 24.
• the layer 32 comprising the active material covers the whole of at least one face of the collector 30, vertically between the lower edge 42 and the upper edge 44, and horizontally between the first side edge 46 and the second side edge 48. It does not cover not the tongue 34 which remains bare.
• the active material is for example a titanium oxide lithiated or capable of being lithiated (or “LTO”), or a titanium and niobium oxide (or “TNO”) or even a mixture of these two compounds (LTO/TNO ), graphite, silicon, lithium metal or an alloy.
• LTO titanium oxide lithiated or capable of being lithiated
• TNO titanium and niobium oxide
• graphite silicon, lithium metal or an alloy.
• the active material comprises one or more of the following compounds: lithiated oxide of nickel, manganese and cobalt (NMC) of formula Li(Ni x Mn y Co z )02, lithiated oxide of nickel, cobalt and aluminum (NCA) of formula Li(Ni x C0yAli. x .y)O2, lithiated iron phosphate (LFP) with the formula LiFePC , mixed lithiated phosphate of iron and manganese (LMFP) with the formula LiFe x Mni. x PO4 and/or a lithium manganese oxide (LNMO).
• NMC lithiated oxide of nickel, manganese and cobalt
• NCA lithiated oxide of nickel, cobalt and aluminum
• NCA lithiated iron phosphate
• LFP mixed lithiated phosphate of iron and manganese
• LNMO lithium manganese oxide
• the collector 36 of each of the second polarity electrodes 26 has for example a substantially polygonal outline, in particular a rectangular outline. It extends in the vertical direction V between a lower edge 62 and an upper edge 64. It extends in the horizontal direction H between a first side edge and a second side edge. The first side edge is located at a further distance from the tab than the second side edge.
• the top edge extends to either side of the tongue, which protrudes from the top edge.
• the height at which the upper edge extends relative to the lower edge is preferably identical on either side of the tab.
• the tongue is preferably integral with the manifold 36.
• the tongue is thus obtained during the production of the manifold 36.
• the tab has a polygonal contour, for example rectangle or square.
• the tongue extends horizontally between a first side edge connected to the upper edge 64 of the manifold 36, and a second side edge, also connected to the upper edge 64 of the manifold 36.
• the tongue further defines an upper edge connecting the first side edge and the second side edge.
• the top edge defines at least one substantially planar surface.
• the height of the tongue taken relative to the upper edge of the manifold 36 is preferably less than 3 mm, preferably between 1 mm and 5 mm.
• the height of the tongue of the second polarity electrodes 26 is preferably substantially identical to the height of the tongue 34 of the first polarity electrodes 24.
• the tongue defines a first face and a second face substantially parallel to the first face disposed opposite the first face.
• the tabs of the second polarity electrodes 26 are arranged next to each other in the stacking direction E, opposite one another. They are advantageously all identical to each other.
• Each tab is spaced from an adjacent tab, in the stacking direction E, by a gap.
• the gap is defined between the first side of a tongue and the second side of the adjacent tongue.
• the width of the gap taken along the stacking direction E is equal to the sum of the widths of l first polarity electrode 24, here negative, of the first separator 28, of the second separator 29, and of two layers 32 of material comprising the active material covering each of the collectors 36 of two adjacent electrodes 26.
• the layer 32 comprising the active material covers the whole of at least one face of the collector 36, vertically between the lower edge 62 and the upper edge 64, and horizontally between the first side edge and the second side edge. It does not cover the tongue which remains bare.
• the tabs 34 of the electrodes 24 of the first polarity, here negative, are arranged away from the tabs of the electrodes of the second polarity 26, here positive, in the horizontal direction H
• Each of the first and second separators 28, 29 is formed from one or more sheets, preferably from one or more electric insulating sheets.
• Each sheet is for example formed from a sheet of polymeric material, in particular from a sheet of polyolefin which is preferably permeable to lithium ions.
• the first separator 28 and the second separator 29 are preferably identical to each other.
• each of the first and second separators 28, 29 is for example less than 25 ⁇ m.
• the electrolyte is for example liquid. It is for example formed from an organic electrolyte containing lithium compounds such as LiPF 6 and solvents. As a variant, the electrolyte is in the form of a solid or a gel, for example based on polyvinylidene fluoride (PVDF) polymers or a copolymer of polyvinylidene fluoride and hexafluoropropylene (PVDF-HFP) as well as solvents or salts.
• PVDF polyvinylidene fluoride
• PVDF-HFP hexafluoropropylene
• the electrochemical bundle comprises a first metal separation device 22 attached to the tabs 34 of the first polarity electrodes 24 and a second metal separation device (not shown) attached to the tabs of the second polarity electrodes 26.
• first metal separation device 22 attached to the tabs 34 of the first polarity electrodes 24
• second metal separation device (not shown) attached to the tabs of the second polarity electrodes 26.
• the first metallic separation device 22 is interposed between each pair of adjacent tongues 34 of the electrodes of first polarity 24, here negative. More particularly, the first separation device 22 is placed in each gap 60 delimited between two adjacent tabs 34 .
• the first separation device 22 is attached to at least one of the tabs 34 of the electrodes 24 of each of the pairs of adjacent electrodes 24.
• the first separation device 22 is attached to each of the tabs 34 of the electrodes 24 of each of the pairs of adjacent electrodes 24.
• the first separation device 22 is welded to the tab or tabs of each pair of adjacent electrodes 24, by at least one weld 66 ( Figure 4).
• the weld 66 is for example a laser weld or an ultrasonic weld.
• the first separation device 22 then electrically connects together the plurality of electrical connection tabs 34 of the first polarity electrodes 24.
• the separation device 22 is glued to the tongue or tongues of each pair of adjacent electrodes 24 by means of an adhesive.
• the adhesive is for example polyvinylidene fluoride (PVDF).
• the first separation device 22 extends, between the tabs 34 of each pair of adjacent electrodes 24, between a lower edge 68 and an upper edge 70 in the vertical direction V.
• Each upper edge 70 of the first separation device 22 extends between the upper edges 54 of two adjacent tabs 34 in the stacking direction E.
• the first separation device 22 is arranged away from the collectors 30, 36 of the first polarity electrodes 24 and of the second polarity electrodes 26, above the collectors 30, 36, in the vertical direction, to avoid any contact with the layers 32 comprising the active material and the second polarity electrodes 26.
• the upper edges 70 of the first separation device 22 are substantially flush with the upper edges 54 of the electrical connection tabs 34 of the plurality of electrodes of first polarity 24.
• substantially is meant that the difference in height between the upper edges 54 of the electrical connection tabs 34 and the upper edges 70 of the first separation device 22, taken in the vertical direction, is between 0 mm and 0.5 mm.
• the upper edges 70 of the first separation device 22 and the upper edges 54 of the tabs 34 extend substantially in the same plane P, substantially parallel to the stacking direction E.
• the width of the first separation device 22 taken along the stacking direction E between two adjacent electrical connection tabs 34 is for example between 60% and 90% of the width of the gap 60.
• the first separation device 22 is in contact with the tongue 34 adjacent to the tongue 34 on which the first separation device 22 is fixed. adjacent and of the weld or welds 66 is substantially equal to the width of the gap 60. In other words, the first separation device 22 is fixed on the first face 56 of a tab 34 and is in contact with the second face 58 of the tongue 34 adjacent.
• the first separation device 22 is formed by a continuous metal strip 72 successively surrounding, in the vertical direction, the first lateral edge 50 of an electrical connection tongue 34 and the second lateral edge 52 of a tab 34 of adjacent electrical connection.
• the first electrical connector 18 comprises at least one substantially planar lower face welded to the upper edges 70 of the first separation device 22 and to the upper edges 54 of the tabs 34 for electrical connection of the first polarity electrodes 24.
• collectors 30, 36 are made by unrolling a strip of metal strip.
• the strip of metal foil is previously coated with an ink comprising in particular the active material to form each electrode.
• the contour of each of the collectors 30, 36 is obtained by stamping.
• the ink also contains a binder and an electronic compound.
• the deposit forms the layer 32 comprising the active material.
• the tabs 34 are not coated with ink comprising the active material.
• Each stack 20 is made by arranging an electrode of first polarity 24, here negative, opposite an electrode of second polarity 26, here positive, with the interposition of the first separator 28 and the second separator 29. The stacks 20 are then themselves stacked successively one after the other in the stacking direction E.
• the first separation device 22 here the metal strip 72, is interposed between each pair of adjacent electrical connection tabs 34.
• the first separation device 22 is then fixed on at least one of the tabs 34 of two adjacent electrodes 24 so that the upper edge 70 of the first fixing device 22 is substantially flush with the upper edges 54 of the electrical connection tabs 34 adjacent.
• the fixing is advantageously carried out by ultrasonic welding using a sonotrode 74.
• the cross section of the head of the sonotrode 74 is between 2 mm and 4 mm.
• one or more substantially spot welds are made between the first separation device 22 and the tongue 34.
• a weld line is made between the first separation device 22 and the tongue 34.
• the section welded to each tab 34 is for example between 1 mm 2 and 10 mm 2 , preferably at least equal to 2 mm 2 .
• the welded section is chosen so as to ensure good mechanical strength between the components.
• the electrical connection tabs 34 are surrounded with the continuous metal strip 72 by successively surrounding in the vertical direction V the first lateral edge 50 of a tab 34 and the second lateral edge 52 of the adjacent tab 34.
• the electrochemical bundle 12 manufactured as above is inserted into the interior volume of the bucket.
• the first electrical connector 18 is then soldered to the upper edges 54 of the electrical connection tabs 34 of the first polarity electrodes 24 and to the upper edges 70 of the first separation device 22.
• the second electrical connector 19 is soldering it to the upper edges of the electrical connection tongues of the second polarity electrodes 26 and to the upper edges of the second separation device.
• Cover 14 provided with terminals 16, 17 is placed above the cup so that terminals 16, 17 are in electrical contact with first electrical connector 18 and second electrical connector 19 respectively.
• the upper edges 54 of the tabs 34 and the upper edges 70 of the first separation device 22 arranged substantially in the same plane facilitate the welding of the first electrical connector 18.
• the height of the tabs 34 of the bundle 12 according to the invention is relatively shorter than the tabs of the state of the art.
• the relative gain in capacity between a battery cell 100 of the state of the art and a battery cell 12 according to the invention is between 5% and 8%.
• the first separation device 22 and the second separation device are each formed by a plurality of separation members 76 distinct from each other.
• Each separation member 76 of the first separation device 22 is interposed between each pair of adjacent connecting tabs 34.
• the separating members 76 are preferably all identical to each other.
• Each separating member 76 extends vertically between a lower edge 78 and an upper edge 80. It extends horizontally between a first side edge 82 and a second side edge 84. The first side edge 82 and the second side edge 84 connect the upper edge 80 and the lower edge 78.
• each separating member 76 taken along the horizontal direction H between the first side edge 82 and the second side edge 84 is between 50% and 100% of the length of the tongues 34 taken along this same direction.
• each separating member 76 is substantially equal to the length of each of the tabs 34.
• the methods for manufacturing the electrochemical bundle 12 and the associated battery element 10 are identical to the methods described above.
• the bucket is replaced by a flexible pouch containing the electrochemical bundle(s) described above.
• the separation device 22 in particular the metal strip 72 is advantageously formed of solid metal, that is to say devoid of macroscopic porosity (for example of pore size greater than 50 ⁇ m).
• the separation device 22 is for example made of copper, stainless steel, nickel or aluminum, depending on the polarity of the electrode.
• the separation device 22 has a thickness advantageously ranging from 10 ⁇ m to 100 ⁇ m.

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• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• Inorganic Chemistry (AREA)
• Materials Engineering (AREA)
• Connection Of Batteries Or Terminals (AREA)
• Electric Double-Layer Capacitors Or The Like (AREA)
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• 2021
  • 2021-12-22 FR FR2114203A patent/FR3131101B1/fr active Active
• 2022
  • 2022-12-20 US US18/722,657 patent/US20250055138A1/en active Pending
  • 2022-12-20 WO PCT/EP2022/086899 patent/WO2023118077A1/fr not_active Ceased
  • 2022-12-20 EP EP22840682.3A patent/EP4454047A1/de active Pending

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