Method for manufacturing an electrochemical cell of a polymer matrix battery

Abstract

The invention relates to a method for manufacturing an electrochemical cell (60) of a polymer matrix battery, which comprises: - covering an anode current collector film (81) with an anode mixture (82) which contains an anode active material dispersed in a first cross-linkable liquid electrolyte containing a first cross-linkable composition, forming an anode electrode (83); - covering a cathode current collector film (91) with a cathode mixture (92) which contains a cathode active material dispersed in a second cross-linkable liquid electrolyte containing a second cross-linkable composition, forming a cathode electrode (93); - stacking the anode electrode and the cathode electrode, with the positioning therebetween of a porous, electrically insulating separator film (71) impregnated with a third cross-linkable liquid or semi-liquid electrolyte, thereby forming a stack (6); and - exposing the stack to at least one electron beam so that the first cross-linkable liquid electrolyte and the second cross-linkable liquid electrolyte solidify in bulk, thereby forming the electrochemical cell.

Description

[0001] DESCRIPTION

[0002] TITLE: Manufacturing process for a polymer matrix electrochemical battery cell

[0003] [Technical field]

[0004] The invention relates to a method for manufacturing an electrochemical battery cell, as well as to an associated installation for manufacturing an electrochemical battery cell.

[0005] The invention finds a preferred application for the manufacture of polymer matrix electrochemical battery cells, which can be used, without limitation, in fields as varied as portable electrical devices such as tools and communication equipment, electric vehicles, whether rolling, flying or floating, or even stationary electrical energy storage installations.

[0006] [State of the art]

[0007] In a known manner, an electrochemical battery cell comprises an anode electrode and a cathode electrode separated by an electrically insulating separator film, and provided respectively with an anode current collector and a cathode current collector.

[0008] To manufacture such an electrochemical cell, and in particular an electrochemical cell with a liquid electrolyte, it is known to use a sealed enclosure to contain a liquid electrolyte which ensures ionic conduction between the anode electrode and the cathode electrode as well as within each of these two electrodes. The major drawbacks lie in the production and sealing of the enclosure, as well as in the filling of the latter with liquid electrolyte and in the subsequent risks of leakage likely to cause incidents such as inflammations, explosions and environmental pollution.

[0009] There is therefore a need for a manufacturing process that is reliable, industrializable and economical.

[0010] Document WO2022 / 013741 thus proposes a manufacturing method which implements the manufacturing of an anode half-cell by solidifying a pasty cathode layer comprising a first electrolyte mixture crosslinkable under radiation, then the manufacturing of an anode half-cell by solidifying a pasty anode layer comprising a second electrolyte mixture crosslinkable under radiation. The assembly of these two half-cells is carried out after having previously subjected each of them to at least one radiation for the initiation of their crosslinking, while interposing a separation layer and before completion of their crosslinking, subsequently ensuring the solidification of the cell.

[0011] Although the half-cells and the separation layer are assembled before complete solidification, this process does not provide optimized surface cohesion between the separation layer and each of the two half-cells, mainly due to the surface effects of the crosslinkable electrolyte mixtures which have started to solidify / crosslink in a non-homogeneous manner between them, so that the ionic conductivity of the cell suffers. The homogeneity of the crosslinking is accentuated by the characteristics of the layer to be crosslinked (thickness, density of the constituents, color, presence of bodies opaque to radiation) making this process unsuitable for very thick electrochemical cells and requiring several stages of deposition of thin layers followed by exposure to radiation to properly initiate the crosslinking of the thin layer.

[0012] [Summary of the invention]

[0013] An aim of the invention is to propose a method for manufacturing an electrochemical battery cell which is both economical and usable on an industrial scale, and which provides improved results in terms of ionic conductivity, electronic conduction and which is suitable for cells of great thickness.

[0014] To this end, the invention provides a method for manufacturing a polymer matrix electrochemical battery cell, comprising the following steps:

[0015] - a first covering step in which an anode current collector film is covered or impregnated with an anode mixture which is in a pasty or semi-liquid state and which contains at least one anode active material dispersed in a first crosslinkable liquid electrolyte containing a first crosslinkable composition, so as to form an anode electrode;

[0016] - a second covering step in which a cathode current collector film is covered or impregnated with a cathode mixture which is in a pasty or semi-liquid state and which contains at least one cathode active material dispersed in a second crosslinkable liquid electrolyte containing a second crosslinkable composition, so as to form a cathode electrode;

[0017] - a third impregnation step during which a porous, electrically insulating separator film is impregnated with a third crosslinkable liquid or semi-liquid electrolyte containing a third crosslinkable composition, so as to form a pre-impregnated separator film;

[0018] - a stacking step during which the anode electrode and the cathode electrode are stacked against each other, by interposing the pre-impregnated separator film, between the anode electrode and the cathode electrode, so as to form a stack;

[0019] - a solidification step, after the stacking step, during which the stack is exposed to at least one electron beam so that the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte solidify in bulk both in the anode electrode, the cathode electrode and the separator film, thus forming the polymer matrix electrochemical cell.

[0020] Thus, the invention proposes to produce two polymer matrix half-cells, which are formed respectively from the anode electrode obtained at the end of the first covering step and the cathode electrode obtained at the end of the second covering step, then to assemble them with the interposition of the separator film (which electrically insulates the two half-cells), which will make it possible to obtain optimal surface cohesion between the separator film and each of the two half-cells.Indeed, since the anode mixture and the cathode mixture are still in a pasty or semi-liquid state and the crosslinking of the first and second crosslinkable liquid electrolytes has not yet begun (in other words the solidification of the anode mixture and the cathode mixture has not yet begun), these first and second crosslinkable liquid electrolytes will be able to be intimately inserted into the pores / holes of the separator film, itself impregnated with the third crosslinkable liquid or semi-liquid electrolyte, during the stacking step and where appropriate in the pores / holes of the current collector films, before solidification (sometimes also called gelation) which will only be initiated after the stacking step, which will then form a continuous polymer matrix throughout the stack at the end of the solidification step.

[0021] In other words, the stacking step, before the solidification step, promotes the interpenetration of the first and second crosslinkable liquid electrolytes, both in the separator film and where appropriate in the current collector films, to obtain a polymer matrix in the entire stack after crosslinking, promoting on the one hand the ionic conductivity between the two electrodes and on the other hand the electronic conductivity between each electrode and its respective current collector, thus allowing subsequent charge and discharge cycles of the final cell.

[0022] It is quite clear that the dimensions of the pores / holes of the separator film are such that the active materials and electron-conducting charges cannot fit inside these pores / holes of the separator film; this separator film must remain an electrically insulating layer, while allowing ionic conduction through it.

[0023] In addition, the third impregnation step is advantageous for increasing the interpenetration and surface cohesion between the separator film and each of the two half-cells, before solidification. In the case where the anode mixture and the cathode mixture contain electron-conducting fillers (as described later), this also makes it possible to reinforce the electrical insulation at the separator film by preventing electron-conducting fillers of the anode mixture (and therefore ultimately of the anode electrode) from coming into contact with electron-conducting fillers of the cathode mixture (and therefore ultimately of the cathode electrode).

[0024] And finally, the solidification step, under exposure to at least one electron beam, will allow a homogeneous solidification in mass by structuring the polymer matrix over the entire thickness of the stack, to form the polymer matrix electrochemical cell which will certainly be solid, but which will have properties equivalent, or at least close, to those of liquid electrolyte cells. Indeed, this process will allow the production of a polymer matrix stack comprising within it interconnected liquid domains or islands, of nanometric or micrometric dimensions, strongly ion exchangers between the anode and cathode electrodes, and containing, where appropriate, electron-conducting charges enveloped within the polymer matrix to ensure electronic conduction in the electrodes towards their respective current collectors.

[0025] With this process, the cell obtained at the end (or final electrochemical cell) can be sectioned to the desired dimensions, thus making it possible to obtain a plurality of electrochemical cells which can be assembled in series, in parallel, in series / parallel, for example by simply superimposing the external conductive faces of the current collector films, to constitute multi-cell batteries.

[0026] According to one variant, the anode mixture and the cathode mixture are pasty or semi-liquid mixtures each having, for example, a viscosity of between 10,000 and 30,000 cps (Centipoises).

[0027] Alternatively, the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte do not contain any electron-conducting charge.

[0028] According to one feature, the first crosslinkable composition, the second crosslinkable composition and the third crosslinkable composition are similar. It is indeed advantageous to use similar (and for example identical) crosslinkable compositions for the two half-cells and the separator film, to promote ionic conduction in the interface zone with the separator film.

[0029] According to one possibility, the first crosslinkable composition, the second crosslinkable composition and the third crosslinkable composition respectively comprise a first monomer or prepolymer mixture, a second monomer or prepolymer mixture and a third monomer or prepolymer mixture, which each comprise monomers or prepolymers or a combination of monomers and prepolymers, wherein the monomers or prepolymers comprise crosslinking functions for solidification of the anode mixture, the cathode mixture and the third crosslinkable liquid or semi-liquid electrolyte upon exposure to the at least one electron beam.

[0030] Advantageously, the first crosslinkable composition and the second crosslinkable composition are each without crosslinking initiator additive.

[0031] The absence of such additives makes it possible to limit the presence of inactive materials and therefore to increase the mass energy density of the cell.

[0032] Alternatively, the crosslinking functions are selected from acrylate, methacrylate, vinyl, styrene, isocyanate, acrylamide and methacrylamide functions.

[0033] Of course, the invention cannot be limited to such functions, but they have the advantage of being effective.

[0034] Alternatively, the first crosslinkable composition has a mass percentage in the anode mixture which is between 2 and 20%, for example between 3 and 7%, and the second crosslinkable composition has a mass percentage in the cathode mixture which is between 2 and 20%, for example between 3 and 7%.

[0035] In a particular embodiment, the first coating step implements roll-to-roll deposition or impregnation of the anode mixture onto the anode current collector film such that the anode electrode forms a first continuous strip, the second coating step implements roll-to-roll deposition or impregnation of the cathode mixture onto the cathode current collector film such that the cathode electrode forms a second continuous strip, and the third impregnation step implements continuous impregnation of the separator film with the third crosslinkable liquid or semi-liquid electrolyte such that the pre-impregnated separator film forms a third continuous strip which is interposed between the first continuous strip and the second continuous strip during the stacking step.

[0036] The roll-to-roll deposition or impregnation technique is particularly advantageous for implementation on an industrial scale, as it is both economical and rapid, which will also allow continuous stacking of the three strips.

[0037] It is further specified that the third crosslinkable liquid or semi-liquid electrolyte does not contain any electron-conducting charge.

[0038] According to one possibility, the third crosslinkable composition is without crosslinking initiator additive.

[0039] Advantageously, the third crosslinkable composition is identical to the first crosslinkable composition and to the second crosslinkable composition.

[0040] Thus, it is sufficient to prepare only one crosslinkable composition which will be used in the first, second and third crosslinkable liquid electrolytes.

[0041] Advantageously, in the third impregnation step, the third crosslinkable liquid or semi-liquid electrolyte is impregnated throughout the entire volume of the separator film, to promote cohesion with the anode electrode and the cathode electrode plated on two opposite faces of the separator film.

[0042] Alternatively, the separator film is continuously unwound from a third reel and continuously impregnated with the third crosslinkable liquid or semi-liquid electrolyte to form the third continuous strip.

[0043] In a variant not covered by the claims, the separator film may not be pre-impregnated with such a third crosslinkable liquid or semi-liquid electrolyte, to be directly and as such intercalated between the two half-cells (in other words between the anode electrode and the cathode electrode); in this case the separator film may for example be in the form of a fine mesh fabric made of electrically insulating polymer.

[0044] In an advantageous embodiment, the stacking step implements a compression of the stack before exposing it to the at least one electron beam.

[0045] The compression of the stack promotes intimate surface contact between the layers, successively the anode electrode, the separator film and the cathode electrode, and also the control of its thickness.

[0046] This compression of the stack can for example be carried out by continuous rolling or by a press, such as a hydraulic or mechanical press. Advantageously, the compression of the stack is carried out by continuous compression, between two rolling rollers of the first continuous strip, the third continuous strip and the second continuous strip.

[0047] Indeed, such compression by continuous rolling promotes productivity, while allowing precise control of the thickness of the stack before solidification.

[0048] According to a particular embodiment, the method comprises a final compression step during which the stack is compressed, for example by continuous rolling or by a press, after having been exposed to at least one electron beam.

[0049] According to one feature, the anode active material comprises particles of anode active material having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers, and the cathode active material comprises particles of cathode active material having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers.

[0050] According to another characteristic, the anode active material particles and the cathode active material particles are spherical or substantially spherical shaped particles.

[0051] Such a spherical, or substantially spherical, shape is advantageous for having anode and cathode mixtures that are homogeneous and thus allow the active particles to be well distributed before mass crosslinking, which is favorable to ionic conduction.

[0052] In a particular embodiment, the anode mixture contains first electron-conducting fillers dispersed in the first crosslinkable liquid electrolyte, and the cathode mixture contains second electron-conducting fillers dispersed in the second crosslinkable liquid electrolyte.

[0053] According to one possibility, the first electron-conducting fillers and the second electron-conducting fillers are fillers having at least one nanometer dimension between 1 and 200 nanometers.

[0054] Alternatively, the first electron-conducting charges and the second electron-conducting charges are:

[0055] - carbon fillers selected from carbon black, carbon nanofibers, titanium nitride-coated carbon nanofibers, carbon nanotubes, graphene powders, and graphene oxide powders; or

[0056] - non-carbon fillers chosen from metal fibers, metal powders such as carbon fluoride powders, aluminum or nickel powders, conductive metal oxides, conductive polymers, and conductive ceramic powders.

[0057] According to one variant, the first electron-conducting fillers and the second electron-conducting fillers have mass percentages in the respective anode mixture and cathode mixture, which are between 0.1 and 10%, and for example between 0.5 and 5%.

[0058] According to one variant, the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte each comprise at least one lithium or sodium salt dissolved in at least one liquid solvent.

[0059] Similarly, the third crosslinkable liquid electrolyte may comprise at least one lithium or sodium salt dissolved in at least one liquid solvent.

[0060] Advantageously, the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte each comprise at least one surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%.

[0061] Such a surfactant promotes the envelopment of electron-conducting charges by the crosslinked monomers or prepolymers, which is advantageous for improving safety and preventing the formation of dendrites.

[0062] Likewise, the third crosslinkable liquid electrolyte may comprise at least one surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%.

[0063] According to one feature, the first covering step involves unwinding the anode current collector film, which is previously wound onto a first reel; and covering or impregnating the anode current collector film with the anode mixture, as it unwinds.

[0064] According to another characteristic, the second covering step involves unwinding the cathode current collector film, which is previously wound on a second reel; and covering or impregnating the cathode current collector film with the cathode mixture, as it is unwound.

[0065] In an advantageous embodiment, the first covering step comprises a first thickness calibration step which consists of a mechanical adjustment of a thickness, called the first thickness, of the anode electrode before the stacking step. In this way, this first thickness is controlled, which promotes control of the thickness of the final cell. Furthermore, this calibration makes it possible to evacuate any excess deposited anode mixture (or excess first crosslinkable liquid electrolyte), which will be evacuated for example at least in part through the lateral parts of the anode electrode and / or where appropriate through the pores / holes of the anode current collector film.

[0066] Advantageously, the first thickness is adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers.

[0067] In a particular embodiment, the first thickness calibration step is implemented by compressing the anode electrode, before the stacking step.

[0068] According to one possibility, the anode electrode is compressed by continuous rolling between two rolling rolls comprising a first input roll and a first output roll.

[0069] Alternatively, the anode current collector film is continuously fed in onto the first input roll, and the anode mixture is deposited to cover or impregnate said anode current collector film at said first input roll to form the anode electrode, said anode electrode being continuously fed between the first input roll and the first output roll to be compressed and then fed out of the first output roll.

[0070] In an advantageous embodiment, the second covering step comprises a second thickness calibration step which consists of a mechanical adjustment of a thickness, called the second thickness, of the cathode electrode.

[0071] In this way, this second thickness is controlled, which promotes control of the thickness of the final cell. Furthermore, this calibration makes it possible to evacuate any excess deposited cathode mixture (or excess second crosslinkable liquid electrolyte), which will be evacuated, for example, at least in part through the lateral parts of the cathode electrode and / or, where appropriate, through the pores / holes of the cathode current collector film.

[0072] Advantageously, the second thickness is adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers.

[0073] In a particular embodiment, the second thickness calibration step is implemented by compressing the cathode electrode, before the stacking step. According to one possibility, the cathode electrode is compressed by continuous rolling between two rolling rolls comprising a second input roll and a second output roll.

[0074] Alternatively, the cathode current collector film is continuously fed in onto the second input roll, and the cathode mixture is deposited to cover or impregnate said cathode current collector film at said second input roll to form the cathode electrode, said cathode electrode being continuously fed between the second input roll and the second output roll to be compressed and then fed out of the second output roll.

[0075] According to a variant, during the solidification step, the stack is exposed to at least one electron beam which comprises:

[0076] - a single electron beam facing one of the anode electrode or the cathode electrode, or

[0077] - two electron beams facing respectively the anode electrode and the cathode electrode.

[0078] To achieve complete solidification of the stack of the electrochemical cell formed, the number of beams will depend on the thickness and mass density of each of the constituent bands of the stack, the irradiation dose emitted by each of the beams and the speed of movement of the stack in front of the electron beam(s).

[0079] According to one characteristic, the at least one electron beam has an irradiation dose characteristic of between 10 and 100 kGy, and for example between 50 and 80 kGy.

[0080] According to another characteristic, the at least one electron beam has an accelerating voltage characteristic of between 100 keV and 1 MeV.

[0081] According to yet another characteristic, a scrolling speed of the stack has a speed characteristic of between 1 and 500 m / min, and for example between 1 and 30 m / min.

[0082] According to one variant, at least one of the anode current collector film and the cathode current collector film is chosen from:

[0083] - a metallic laminated film, for example copper or aluminum, provided with perforations;

[0084] - a porous metallic composite film based on polymer(s) and metallic fibers assembled to form a non-woven fabric; - a porous carbon composite film based on polymer(s) and carbon fibers assembled to form a non-woven fabric, the carbon fibers having possibly (therefore not necessarily) been subjected to pretreatment to improve their electronic and thermal conductivities;

[0085] - a porous film based on carbon fibers assembled to form a non-woven fabric, the carbon fibers having possibly (therefore not necessarily) been pre-treated to improve their electronic and thermal conductivities.

[0086] It is noted that when the anode current collector film is a metal laminated film, the first coating step involves coating this metal laminated film with the anode mixture. Similarly, when the cathode current collector film is a metal laminated film, the second coating step involves coating this metal laminated film with the cathode mixture.

[0087] When the anode current collector film is a porous film, the first coating step involves impregnation of this porous film with the anode mixture. Similarly, when the cathode current collector film is a porous film, the second coating step involves impregnation of this porous film with the cathode mixture.

[0088] According to one possibility, the perforations of the metallic laminated film have maximum dimensions between 0.5 and 2 millimeters and are distributed with a density between 2 and 10 perforations per cm2.

[0089] Alternatively, the pretreatment comprises depositing on the carbon fibers a pretreatment layer based on titanium nitride or titanium carbide or titanium nitride and carbide, said pretreatment layer having a thickness of between 100 and 1000 nanometers.

[0090] In one embodiment, the anode current collector film comprises an inner anode face on which the anode mixture is deposited or impregnated during the first covering step, and an outer anode face, opposite the inner anode face, where said outer anode face is covered or impregnated beforehand with a layer of conductive varnish which is waterproof and electrically conductive; and the cathode current collector film comprises an inner cathode face on which the cathode mixture is deposited or impregnated during the second covering step, and an outer cathode face, opposite the inner cathode face, where said outer cathode face is covered or impregnated beforehand with another layer of conductive varnish which is waterproof and electrically conductive.These two layers of conductive varnish will at least partially ensure the sealing of the cell; the technical purpose of such sealing being to prevent the entry of moisture and air into the electrochemical cell, as well as the evaporation of solvents from the liquid electrolytes. These two layers of conductive varnish may, for example, harden upon exposure to at least one electron beam during the solidification step (of the electrochemical cell), or be hardened before the covering steps.

[0091] According to one characteristic, the conductive varnish layer and the other conductive varnish layer each have a thickness less than or equal to 30 micrometers, for example between 5 and 30 micrometers.

[0092] Advantageously, the first recovery step and the second recovery step are carried out in parallel.

[0093] In an advantageous embodiment, the stack has two opposite longitudinal edges, and the manufacturing method comprises a step of applying electrically insulating varnish, after the stacking step and before the solidification step, during which two layers of electrically insulating varnish, waterproof and electrically insulating, are deposited respectively on the two opposite longitudinal edges of the stack.

[0094] These two layers of electrically insulating varnish will contribute to the sealing of the cell.

[0095] Advantageously, the two layers of electrically insulating varnish harden upon exposure to at least one electron beam during the solidification step.

[0096] Thus, this electrical insulating varnish comprises monomers or prepolymers or a combination of monomers and prepolymers, wherein the monomers or prepolymers comprise crosslinking functions for solidification upon exposure to the at least one electron beam.

[0097] Advantageously, the anode current collector film has two opposite longitudinal edges defining between them a width of the anode current collector film, and the anode mixture is deposited to cover or impregnate said anode current collector film, during the first covering step, to form a strip having a width less than the width of the anode current collector film, thus leaving the two longitudinal edges of the anode current collector film uncovered and unimpregnated with the anode mixture, the cathode current collector film has two opposite longitudinal edges defining between them a width of the cathode current collector film, and the cathode mixture is deposited to cover or impregnate said cathode current collector film, during the second covering step, to form a strip having a width less than the width of the cathode current collector film,thus leaving the two longitudinal edges of the cathode current collector film uncovered and unimpregnated with the cathode mixture, so that the two opposite longitudinal edges of the stack are free of the anode mixture and the cathode mixture before the step of applying the electrically insulating varnish.,

[0098] According to one variant, the active anode material is chosen from anode materials, used alone or in combination, based on:

[0099] - carbon, such as graphite,

[0100] - silicon,

[0101] - carbonaceous silicon or lithiated silicon,

[0102] - transition metals or transition metal alloys,

[0103] - composite materials combining transition metals and carbon,

[0104] - lithium metal,

[0105] - sodium metal,

[0106] - lithium titanate,

[0107] - aluminum, or magnesium, or tin, or zinc.

[0108] According to another variant, the active cathode material is chosen from cathode materials, used alone or in combination, based on:

[0109] - Nickel Manganese Cobalt lithiated,

[0110] - Nickel Cobalt Lithium aluminum,

[0111] - Lithium iron phosphate,

[0112] - Lithium Cobalt Oxide lithiated,

[0113] - Manganese oxide lithium,

[0114] - sulfur-carbon composite in the presence of a lithiated anode material,

[0115] - lithium sulfide,

[0116] - sodium alloy, such as with Na3V2(PO4)2F3.

[0117] In one embodiment, the first covering step, the second covering step, the stacking step and the solidification step are carried out in an anhydrous atmosphere, and for example in an argon or carbon dioxide atmosphere.

[0118] This atmosphere is beneficial for process safety.

[0119] The invention also relates to an installation for manufacturing an electrochemical cell of a polymer matrix battery, comprising the following stations: - a first covering station comprising a first distributor of an anode current collector film, a first reservoir containing an anode mixture which is in a pasty or semi-liquid state and which contains at least one anode active material dispersed in a first crosslinkable liquid electrolyte containing a first crosslinkable composition, and a first covering unit for covering or impregnating the anode current collector film with the anode mixture so as to form an anode electrode;

[0120] - a second covering station comprising a second distributor of a cathode current collector film, a second reservoir containing a cathode mixture which is in a pasty or semi-liquid state and which contains at least one cathode active material dispersed in a second crosslinkable liquid electrolyte containing a second crosslinkable composition, and a second covering unit for covering or impregnating the cathode current collector film with the cathode mixture so as to form a cathode electrode;

[0121] - a third impregnation station comprising a third distributor of a separator film, electrically insulating and porous, and an impregnation unit for impregnating the separator film with a third crosslinkable liquid or semi-liquid electrolyte so as to form a pre-impregnated separator film;

[0122] - a stacking station for stacking the anode electrode and the cathode electrode, with an interposition of the pre-impregnated separator film between the anode electrode and the cathode electrode, to form a stack;

[0123] - a solidification station, at the outlet of the stacking station, comprising at least one electron beam generator for exposing said stack to at least one electron beam so that the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte solidify in mass both in the anode electrode, the cathode electrode and the separator film, thus forming the polymer matrix electrochemical cell.

[0124] This installation may also have all or part of the characteristics associated with the process described above.

[0125] [Brief description of the figures]

[0126] Other characteristics and advantages of the present invention will appear on reading the detailed description below, of a non-limiting example of implementation, made with reference to the appended figures in which:

[0127] [Fig 1] is a schematic view of a manufacturing installation according to an exemplary embodiment of the invention, suitable for implementing a manufacturing method, according to the invention, of an electrochemical cell of a polymer matrix battery;

[0128] [Fig 2] is a schematic view of the first coating unit of the installation of Figure 1, for coating or impregnating an anode current collector film with an anode mixture and forming an anode electrode;

[0129] [Fig 3] is a schematic view of the second coating unit of the installation of Figure 1, for coating or impregnating a cathode current collector film with a cathode mixture and forming a cathode electrode;

[0130] [Fig 4] is a schematic view of the impregnation unit of the third impregnation station, and of the stacking station of the installation of Figure 1, for stacking the anode electrode and the cathode electrode, with an interposition of the pre-impregnated separator film;

[0131] [Fig 5] is a schematic top view of an anode current collector film partially coated with the anode mixture in the first coating unit;

[0132] [Fig 6] is a schematic top view of a cathode current collector film partially coated with the cathode mixture in the second coating unit;

[0133] [Fig 7] is a schematic sectional view of a polymer matrix battery electrochemical cell obtained at the outlet of the installation;

[0134] [Fig 8] is a schematic cross-sectional view of a variant of a polymer matrix battery electrochemical cell;

[0135] [Fig 9] is a schematic view of a bobbin winder, which follows the setup of Figure 1 to form a cell coil.

[0136] [Detailed description of one or more embodiments of the invention]

[0137] Figure 1 illustrates an installation 9 for manufacturing an electrochemical cell of a polymer matrix battery 60, and its various stations described below.

[0138] The installation 9 comprises a first covering station 1 which comprises a first distributor 10 for distributing an anode current collector film 81. This first distributor 10 is in the form of a reel unwinder or reel, and the anode current collector film 81 is in the form of a first reel 810 which is unwound from the first distributor 10 continuously. This anode current collector film 81 is chosen from:

[0139] - a metallic laminated film, for example copper or aluminium, provided with perforations, the maximum dimensions of which are for example between 0.5 and 2 millimetres and which are distributed with a density of for example between 2 and 10 perforations per cm2;

[0140] - a porous metallic composite film based on polymer(s) and metallic fibers assembled to form a non-woven fabric;

[0141] - a porous carbon composite film based on polymer(s) and carbon fibers assembled to form a non-woven fabric, the carbon fibers having optionally undergone pretreatment to improve their electronic and thermal conductivities;

[0142] - a porous film based on carbon fibers assembled to form a non-woven fabric, the carbon fibers having possibly been pre-treated to improve their electronic and thermal conductivities.

[0143] This pretreatment of carbon fibers consists, for example, of depositing on the carbon fibers a pretreatment layer based on titanium nitride or titanium carbide or titanium nitride and carbide, this pretreatment layer having, for example, a thickness of between 100 and 1000 nanometers.

[0144] The anode current collector film 81 has an inner face and an opposite outer face. According to one possibility, the outer face of the anode current collector film 81 is covered or impregnated beforehand with a layer of conductive varnish 66 (see Figure 8) which is waterproof and electrically conductive. This layer of conductive varnish 66 has for example a thickness less than or equal to 30 micrometers, for example between 5 and 30 micrometers.

[0145] The first covering station 1 also comprises a first reservoir 11 containing an anode mixture 82 which is in a pasty or semi-liquid state (for example with a viscosity of between 10,000 and 30,000 cps) and which contains at least one anode active material and first electron-conducting fillers dispersed in a first crosslinkable liquid electrolyte containing a first crosslinkable composition.

[0146] This first tank 11 is a sealed tank and in an anhydrous atmosphere, and for example in an atmosphere of an inert gas such as for example argon or carbon dioxide. This first tank 11 is advantageously equipped with a mechanical mixer or agitator 110 to homogenize the anode mixture 82.

[0147] According to one possibility, the first crosslinkable composition has a mass percentage in the anode mixture 82, which is between 2 and 20%, and for example between 3 and 7%. This first crosslinkable composition comprises a first monomer or prepolymer mixture, which comprises monomers or prepolymers or a combination of monomers and prepolymers, where the monomers or prepolymers comprise crosslinking functions for crosslinking the first crosslinkable liquid electrolyte (and therefore solidification of the anode mixture 82) upon exposure to an electron beam. These crosslinking functions are for example chosen from acrylate, methacrylate, vinyl, styrene, isocyanate, acrylamide and methacrylamide functions.

[0148] According to one possibility, the first electron-conducting fillers have a mass percentage in the anode mixture 82, which is between 0.1 and 10%, and for example between 0.5 and 5%. These first electron-conducting fillers are advantageously fillers having at least one nanometric dimension between 1 and 200 nanometers, and are:

[0149] - either carbon fillers chosen from carbon black, carbon nanofibers, carbon nanofibers coated with titanium nitride, carbon nanotubes, graphene powders, and graphene oxide powders;

[0150] - either non-carbon fillers chosen from metal fibers, metal powders such as carbon fluoride powders, aluminum or nickel powders, conductive metal oxides, conductive polymers, and conductive ceramic powders.

[0151] Alternatively, the first crosslinkable liquid electrolyte comprises at least one lithium or sodium salt dissolved in at least one liquid solvent. It is conceivable that the first crosslinkable liquid electrolyte comprises a surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%.

[0152] Alternatively, the anode active material comprises particles of anode active material having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers. These particles of anode active material are advantageously particles of spherical or substantially spherical shape. This anode active material is chosen from anode materials, used alone or in combination, based on:

[0153] - carbon, such as graphite,

[0154] - silicon,

[0155] - carbonaceous silicon or lithiated silicon,

[0156] - transition metals or transition metal alloys,

[0157] - composite materials combining transition metals and carbon, - lithium-metal,

[0158] - sodium metal,

[0159] - lithium titanate,

[0160] - aluminum, or magnesium, or tin, or zinc.

[0161] The first covering station 1 further comprises a first covering unit 12 for covering or impregnating the anode current collector film 81, and more specifically its inner face, with the anode mixture 82 so as to form an anode electrode 83 comprising the anode current collector film 81 at least partially impregnated with the first crosslinkable liquid electrolyte and a layer of the anode mixture 82.

[0162] The first recovery post 1 thus implements:

[0163] - an unwinding of the anode current collector film 81, which is previously wound on the first reel 810 on the first distributor 10; and

[0164] - the covering or impregnation, at the level of the first covering unit 12, of the anode current collector film 81 by the anode mixture 82, as it unwinds; the supply of the anode mixture 82 coming from the first reservoir 11 via a pipe 111.

[0165] This first covering unit 12 implements roll-to-roll deposition or impregnation of the anode mixture 82 onto the anode current collector film 81 so that the anode electrode 83 forms a first continuous strip, and also implements compression of the anode electrode 83 by continuous rolling between two rolling rollers 13, 14 comprising a first input roller 13 and a first output roller 14. Also, the first covering unit 12 comprises these two rolling rollers 13, 14.

[0166] Thus, the anode current collector film 81 is continuously fed into the inlet on the first inlet roller 13, and the anode mixture 82 is deposited or impregnated onto the inner face of the anode current collector film 81 at this first inlet roller to form the anode electrode 83. The first covering unit 12 thus comprises a deposition nozzle 15 which is fluidically connected to the first reservoir 11 by means of the line 111, and which is arranged adjacent to the first inlet roller 13 for depositing or impregnating anode mixture 82 onto the inner face of the anode current collector film 81.

[0167] Referring to Figure 5, the anode current collector film 81 has two opposite longitudinal edges 811 defining between them a width L81 of the anode current collector film 81 (the arrow in this Figure 5 illustrating the direction of advancement or conveyance in the installation 9) and, according to an optional possibility, the anode mixture 82 is deposited or impregnated on the anode current collector film 81, in the first covering unit 12, to form a strip having a width L82 smaller than the width L81 of the anode current collector film 81, thus leaving the two longitudinal edges 811 of the anode current collector film 81 uncovered and unimpregnated with the anode mixture 82. In other words, the anode current collector film 81 has two edge strips 812, along these two respective longitudinal edges 811, which are not covered and not impregnated with the anode mixture 82.

[0168] The width L82 of this strip is preferably greater than or equal to 90% of the width L81 of the anode current collector film 81, thus leaving approximately 5% uncovered on each of the two edge strips 812 of the anode current collector film 81. Alternatively, the anode mixture 82 is deposited or impregnated over the entire width L81 of the anode current collector film 81.

[0169] The first coating unit 12 also comprises a scraper 16 which is arranged adjacent to the first inlet roller 13 and after the deposition nozzle 15, for scraping off excess anode mixture 82 deposited on the anode current collector film 81.

[0170] Following deposition by the deposition nozzle 15 and scraping by the scraper 16, the anode electrode 83 is continuously conveyed between the first input roller 13 (which is a fixed roller) and the first output roller 14 (which is a movable roller with a compression spring) to be compressed and then conveyed out of the first output roller 14. Thus, the anode electrode 83 is compressed by continuous rolling between these two rolling rollers 13, 14.

[0171] This rolling compression thus allows a thickness calibration which consists of a mechanical adjustment of a thickness, called first thickness El, of the anode electrode 83. This first thickness El is advantageously adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers. The first covering unit 12 may comprise a first thickness sensor 17 placed on the path of the anode electrode 83 to measure this first thickness El, and thus serve to control the compression operation.

[0172] This rolling compression also promotes the impregnation of the first crosslinkable liquid electrolyte in the thickness of the anode current collector film 81. This rolling compression also makes it possible to extract any surplus of first crosslinkable liquid electrolyte, which will be evacuated through porosities in the anode active material and / or holes in the anode current collector film 81; this surplus of first crosslinkable liquid electrolyte can be recovered in a recovery tank 18.

[0173] The installation 9 comprises a second covering station 2 which comprises a second distributor 20 for distributing a cathode current collector film 91. This second distributor 20 is in the form of a reel unwinder or reel, and the cathode current collector film 91 is in the form of a second reel 910 which is unwound from the second distributor 20 continuously.

[0174] This cathode current collector film 91 is chosen from:

[0175] - a metallic laminated film, for example copper or aluminium, provided with perforations, the maximum dimensions of which are for example between 0.5 and 2 millimetres and which are distributed with a density of for example between 2 and 10 perforations per cm2;

[0176] - a porous metallic composite film based on polymer(s) and metallic fibers assembled to form a non-woven fabric;

[0177] - a porous carbon composite film based on polymer(s) and carbon fibers assembled to form a non-woven fabric, the carbon fibers having optionally undergone pretreatment to improve their electronic and thermal conductivities;

[0178] - a porous film based on carbon fibers assembled to form a non-woven fabric, the carbon fibers having possibly been pre-treated to improve their electronic and thermal conductivities.

[0179] This pretreatment of carbon fibers consists, for example, of depositing on the carbon fibers a pretreatment layer based on titanium nitride or titanium carbide or titanium nitride and carbide, this pretreatment layer having, for example, a thickness of between 100 and 1000 nanometers.

[0180] The cathode current collector film 91 has an opposite inner face and an outer face. According to one possibility, the outer face of the cathode current collector film 91 is covered or impregnated beforehand with another layer of conductive varnish 67 (see Figure 8) which is waterproof and electrically conductive. This other layer of conductive varnish 67 has for example a thickness less than or equal to 30 micrometers, for example between 5 and 30 micrometers.

[0181] The second covering station 2 also comprises a second reservoir 21 containing a cathode mixture 92 which is in a pasty or semi-liquid state (for example with a viscosity of between 10,000 and 30,000 cps) and which contains at least one cathode active material and second electron-conducting fillers dispersed in a second crosslinkable liquid electrolyte containing a second crosslinkable composition.

[0182] This second tank 21 is a sealed tank and in an anhydrous atmosphere, and for example in an atmosphere of an inert gas such as for example argon or carbon dioxide. This second tank 21 is advantageously equipped with a mechanical mixer or stirrer 210 to homogenize the cathode mixture 92.

[0183] According to one possibility, the second crosslinkable composition has a mass percentage in the cathode mixture 92, which is between 2 and 20%, and for example between 3 and 7%. This first crosslinkable composition comprises a second monomer or prepolymer mixture, which comprises monomers or prepolymers or a combination of monomers and prepolymers, where the monomers or prepolymers comprise crosslinking functions for solidification of the second crosslinkable liquid electrolyte upon exposure to an electron beam. These crosslinking functions are for example chosen from acrylate, methacrylate, vinyl, styrene, isocyanate, acrylamide and methacrylamide functions.

[0184] Advantageously, the first crosslinkable composition and the second crosslinkable composition are analogous, and for example they are identical.

[0185] According to one possibility, the second electron-conducting fillers have a mass percentage in the cathode mixture 92, which is between 0.1 and 10%, and for example between 0.5 and 5%. These first electron-conducting fillers are advantageously fillers having at least one nanometric dimension between 1 and 200 nanometers, and are:

[0186] - either carbon fillers chosen from carbon black, carbon nanofibers, carbon nanofibers coated with titanium nitride, carbon nanotubes, graphene powders, and graphene oxide powders;

[0187] - either non-carbon fillers chosen from metal fibers, metal powders such as carbon fluoride powders, aluminum or nickel powders, conductive metal oxides, conductive polymers, and conductive ceramic powders.

[0188] According to another possibility, the second crosslinkable liquid electrolyte comprises at least one lithium or sodium salt dissolved in at least one liquid solvent. It is conceivable that the second crosslinkable liquid electrolyte comprises a surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%. According to another possibility, the cathode active material comprises particles of cathode active material having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers. These particles of cathode active material are advantageously particles of spherical or substantially spherical shape. This cathode active material is chosen from cathode materials, used alone or in combination, based on:

[0189] - Nickel Manganese Cobalt lithiated,

[0190] - Nickel Cobalt Lithium aluminum,

[0191] - Lithium iron phosphate,

[0192] - Lithium Cobalt Oxide lithiated,

[0193] - Manganese oxide lithium,

[0194] - sulfur-carbon composite in the presence of a lithiated anode material,

[0195] - lithium sulfide,

[0196] - sodium alloy, such as with Na3V2(PO4)2F3.

[0197] The second covering station 2 further comprises a second covering unit 22 for covering or impregnating the cathode current collector film 91, and more specifically its inner face, with the cathode mixture 92 so as to form a cathode electrode 93 comprising the cathode current collector film 91 at least partially impregnated with the second crosslinkable liquid electrolyte and a layer of the cathode mixture 92.

[0198] The second recovery station 2 thus implements:

[0199] - an unwinding of the cathode current collector film 91, which is previously wound on the second reel 910 on the second distributor 20; and

[0200] - the covering or impregnation, at the level of the second covering unit 22, of the cathode current collector film 91 by the cathode mixture 92, as it unwinds; the supply of the cathode mixture 92 coming from the second reservoir 21 via a pipe 211.

[0201] This second covering unit 22 implements roll-to-roll deposition or impregnation of the cathode mixture 92 onto the cathode current collector film 91 so that the cathode electrode 93 forms a second continuous strip, and also implements compression of the cathode electrode 93 by continuous rolling between two rolling rollers 23, 24 comprising a second input roller 23 and a second output roller 24. Also, the second covering unit 22 comprises these two rolling rollers 23, 24.

[0202] Thus, the cathode current collector film 91 is continuously fed into the second inlet roller 23, and the cathode mixture 92 is deposited or impregnated onto the inner face of the cathode current collector film 91 at this second inlet roller 23 to form the cathode electrode 93. The second covering unit 22 thus comprises a deposition nozzle 25 which is fluidically connected to the second reservoir 21 by means of the line 211, and which is arranged adjacent to the second inlet roller 23 for depositing or impregnating cathode mixture 92 onto the inner face of the cathode current collector film 91.

[0203] With reference to Figure 6, the cathode current collector film 91 has two opposite longitudinal edges 911 defining between them a width L91 of the cathode current collector film 91 (the arrow in this Figure 6 illustrating the direction of advancement or conveyance in the installation 9) and, according to an optional possibility, the cathode mixture 92 is deposited or impregnated on the cathode current collector film 91, in the second covering unit 22, to form a strip having a width L92 smaller than the width L91 of the cathode current collector film 91, thus leaving the two longitudinal edges 911 of the cathode current collector film 91 uncovered and unimpregnated with the cathode mixture 92. In other words, the cathode current collector film 91 has two edge strips 912, along these two respective longitudinal edges 911, which are not covered and not impregnated with the cathode mixture 91.

[0204] The width L92 of this strip is preferably greater than or equal to 90% of the width L91 of the cathode current collector film 91, thus leaving approximately 5% uncovered on each of the two edge strips 912 of the cathode current collector film 91. Alternatively, the cathode mixture 92 is deposited or impregnated over the entire width L91 of the cathode current collector film 91.

[0205] The second coating unit 22 also comprises a scraper 26 which is disposed adjacent to the second inlet roller 23 and after the deposition nozzle 25, for scraping off excess cathode mixture 92 deposited on the cathode current collector film 91.

[0206] Following deposition by the deposition nozzle 26 and scraping by the scraper 26, the cathode electrode 93 is continuously fed between the second input roller 23 (which is a fixed roller) and the second output roller 24 (which is a movable roller with a compression spring) to be compressed and then fed out of the second output roller 24. Thus, the cathode electrode 93 is compressed by continuous rolling between these two rolling rollers 23, 24.

[0207] This rolling compression thus allows a thickness calibration which consists of a mechanical adjustment of a thickness, called second thickness E2, of the cathode electrode 93. This second thickness E2 is advantageously adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers. The second covering unit 22 may comprise a second thickness sensor T1 placed on the path of the cathode electrode 93 to measure this second thickness E2, and thus serve to control the compression operation.

[0208] This rolling compression also promotes the impregnation of the second crosslinkable liquid electrolyte into the thickness of the cathode current collector film 91. This rolling compression also makes it possible to extract any surplus of second crosslinkable liquid electrolyte, which will be evacuated through porosities in the cathode active material and / or holes in the cathode current collector film 91; this surplus of second crosslinkable liquid electrolyte can be recovered in a recovery tank 28.

[0209] The installation 9 comprises a third impregnation station 3 which comprises a third distributor 30 for distributing a separator film 71 which is porous and electrically insulating. This third distributor 30 is in the form of a reel unwinder or reel, and the separator film 71 is in the form of a third reel 710 which is unwound from the third distributor 30 continuously. The separator film 71 has an inner face and an opposite outer face.

[0210] This third impregnation station 3 comprises an impregnation unit 32 for impregnating the separator film 71 with a third crosslinkable liquid or semi-liquid electrolyte 72; this third crosslinkable liquid or semi-liquid electrolyte 72 containing a third crosslinkable composition for solidification of said third crosslinkable liquid or semi-liquid electrolyte under exposure to an electron beam.

[0211] This third impregnation station 3 also comprises a third tank 31 containing the third crosslinkable liquid or semi-liquid electrolyte 72 containing the third crosslinkable composition. This third tank 31 is a sealed tank and in an anhydrous atmosphere, and for example in an atmosphere of an inert gas such as for example argon or carbon dioxide. This third tank 31 is advantageously equipped with a mechanical mixer or stirrer 310 to homogenize the third crosslinkable liquid or semi-liquid electrolyte 72.

[0212] According to one possibility, the third crosslinkable composition comprises a third monomer or prepolymer mixture, which comprises monomers or prepolymers or a combination of monomers and prepolymers, wherein the monomers or prepolymers comprise crosslinking functions for solidification of the third crosslinkable liquid or semi-liquid electrolyte upon exposure to an electron beam. These crosslinking functions are for example selected from acrylate, methacrylate, vinyl, styrene, isocyanate, acrylamide and methacrylamide functions.

[0213] Advantageously, the third crosslinkable composition is analogous, and for example identical, to the first crosslinkable composition and to the second crosslinkable composition.

[0214] Alternatively, the third crosslinkable liquid or semi-liquid electrolyte comprises at least one lithium or sodium salt dissolved in at least one liquid solvent. It is conceivable that the third crosslinkable liquid or semi-liquid electrolyte comprises a surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%.

[0215] Advantageously, the third crosslinkable liquid or semi-liquid electrolyte is analogous, and for example identical, to the first crosslinkable liquid electrolyte and / or to the second crosslinkable liquid electrolyte.

[0216] The impregnation unit 32 is shaped to impregnate the third crosslinkable liquid or semi-liquid electrolyte 72 on the two opposite faces (inner face and outer face) of the separator film 71, in order to impregnate the separator film 71 with the third crosslinkable liquid or semi-liquid electrolyte 72 over the entire volume of this separator film 71. Thus, the separator film 71 is continuously conveyed to the inlet of the impregnation unit 32, and the third crosslinkable liquid or semi-liquid electrolyte 72 is impregnated on the two opposite faces of the separator film 71, in the entire volume of the separator film 71, to form a pre-impregnated separator film 73 which is in the form of a third continuous strip.In other words, the separator film 71 is continuously unwound from the third reel 710 and is continuously impregnated with the third crosslinkable liquid or semi-liquid electrolyte 72 to form the pre-impregnated separator film 73 in the form of the third continuous strip 73.

[0217] The impregnation unit 32 comprises two deposition nozzles 35 which are in fluid connection with the third reservoir 31 by means of a pipe 311, and which are arranged facing respectively the internal face and the external face of the separator film 71 to deposit the third crosslinkable liquid or semi-liquid electrolyte 72 on the internal face and the external face of the separator film 71. The impregnation unit 32 also comprises two scrapers 36 which are arranged after the two respective deposition nozzles 35, to scrape off excess third crosslinkable liquid or semi-liquid electrolyte 72 impregnated on the two opposite faces of the separator film 71. The first covering station 1, the second covering station 2 and the third impregnation station 3 operate continuously and in parallel.

[0218] The installation 9 comprises a stacking station 4 for stacking the anode electrode 83 (which forms the first continuous strip at the outlet of the first covering station 1) and the cathode electrode 93 (which forms the second continuous strip at the outlet of the second covering station 2), with an interposition of the pre-impregnated separator film 73 (which forms the third continuous strip 73 at the outlet of the third impregnation station 3) between the anode electrode 83 and the cathode electrode 93. Thus, on this stacking station 4, the third continuous strip (or pre-impregnated separator film 73) is interposed or interposed between the first continuous strip (or anode electrode 83) and the second continuous strip (or cathode electrode 93).

[0219] Thus, this stacking station 4 makes it possible to obtain at the output and continuously a stack 6 successively comprising the anode current collector film 81 (partially impregnated with the first crosslinkable liquid electrolyte), the anode mixture 82, the separator film 71 impregnated with the third crosslinkable liquid or semi-liquid electrolyte 72, the cathode mixture 92 and the cathode current collector film 91 (partially impregnated with the second crosslinkable liquid electrolyte).

[0220] This stacking station 4 implements a compression of the stack 6, for example by continuous rolling or by a press, before exposing it to at least one electron beam. This compression makes it possible to make the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte penetrate into the separator film 71, and therefore to associate them with the third crosslinkable liquid or semi-liquid electrolyte of the third continuous strip (or pre-impregnated separator film 73).

[0221] In the example illustrated in Figure 4, the stacking station 4 comprises a continuous rolling mill having two rolling rollers 41 (with for example a fixed roller and a movable roller with compression spring) to carry out continuous compression of the stack 6.

[0222] The installation 9 comprises, at the outlet of the stacking station 4, a solidification station 5 comprising at least one electron beam generator 50 for exposing the stack 6 to at least one electron beam so that the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte crosslink or solidify in bulk both in the anode current collector film 81, the anode mixture 82, the cathode mixture 92, the cathode current collector film 91 and the separator film 71, thus forming the polymer matrix electrochemical cell 60.Under the effect of the electron beam(s), the crosslinking functions of the first crosslinkable composition, the second crosslinkable composition and the third crosslinkable composition will produce a mass solidification of the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte, thus forming a polymer matrix for the electrochemical cell 60 resulting from the installation 9 and therefore from the process implemented in this installation 9.

[0223] In the example illustrated in Figure 1, the solidification station 5 comprises two electron beam generators 50 facing respectively the anode electrode 83 and the cathode electrode 93, in other words on either side of the stack 6 at the outlet of the stacking station 4.

[0224] Alternatively, and depending on whether the thickness and mass densities of the constituent strips of the polymer matrix electrochemical cell 60 in question allow it, the solidification station 5 may comprise a single electron beam generator 50 facing one of the anode electrode 83 or the cathode electrode 93.

[0225] The or each electron beam generator 50 has:

[0226] - an irradiation dose characteristic between 10 and 100 kGy, and for example between 50 and 80 kGy;

[0227] - an acceleration voltage characteristic between 100 keV and 1 MeV.

[0228] According to one possibility, the running speed of the stack 6, at the solidification station 5, has a speed characteristic of between 1 and 500 m / min, and for example between 1 and 30 m / min; this running speed being ensured by ensuring synchronization of the speeds in the previous stations, and in particular in the first covering station 1, the second covering station 2 and the third impregnation station 3 which operate continuously.

[0229] Optionally, the installation 9 comprises, between the stacking station 4 and the solidification station 5, an electrically insulating varnish application station for depositing two layers of electrically insulating varnish 68 (see Figure 8), waterproof and electrically insulating, on the two opposite longitudinal edges of the stack 6; where this electrically insulating varnish comprises monomers or prepolymers which comprise crosslinking functions for the solidification of the electrically insulating varnish upon exposure to at least one electron beam. Thus the two layers of electrically insulating varnish 68 harden in the solidification station 5, upon exposure to the electron beam(s) 50.The use of these layers of electrically insulating varnish 68 is suitable in the case described above (and illustrated in Figure 5 and Figure 6), where the two longitudinal edges 810 of the anode current collector film 81 are not covered and not impregnated with the anode mixture 82 and where the two longitudinal edges 910 of the cathode current collector film 91 are not covered and not impregnated with the cathode mixture 92, so that in this case the two opposite longitudinal edges of the stack 6 are free of the anode mixture 82 and the cathode mixture 92 before the application of electrically insulating varnish.

[0230] The installation 9 comprises, at the outlet of the solidification station 5, a final compression station 55 for compressing the stack 6, for example by continuous rolling or by a press, after having been exposed to the electron beam(s), in other words for compressing the polymer matrix electrochemical cell 60.

[0231] In the illustrated example, the final compression station 55 comprises a continuous rolling mill having two rolling rollers 56 (with for example a fixed roller and a movable roller with compression spring) to carry out continuous compression of the polymer matrix electrochemical cell 60.

[0232] This polymer matrix electrochemical cell 60 is then in the form of a continuous strip which can be wound in the form of a cell coil 61 on a coil winder 62, as illustrated in Figure 9.

[0233] Advantageously, the first covering unit 12, the second covering unit 22, the impregnation unit 32, the stacking station 4, the solidification station 5 and the final compression station 55 are arranged in an enclosure 57 in an anhydrous atmosphere, and for example in an argon or carbon dioxide atmosphere. The first distributor 10, the second distributor 20 and the third distributor 30 may be outside the enclosure 57.

[0234] Figure 7 schematically illustrates a cross-section of the polymer matrix electrochemical cell 60 obtained at the outlet of the installation 9, with a superposition:

[0235] - the anode current collector film 81 inside which the first electrolyte has solidified, in particular at the interface with the anode mixture 82;

[0236] - of the anode mixture 82 inside which the first electrolyte has solidified, taking in the mass the first electron-conducting charges (of nanometric dimensions) and the particles of active anode material (of micrometric dimensions);

[0237] - the separator film 71 inside which the third electrolyte has solidified, as well as the first electrolyte at the interface with the anode mixture 82 and the second electrolyte at the interface with the cathode mixture 92;

[0238] - of the cathode mixture 92 inside which the second electrolyte has solidified, taking into the mass the second electron-conducting charges (of nanometric dimensions) and the particles of active cathode material (of micrometric dimensions);

[0239] - the cathode current collector film 91 inside which the second electrolyte has solidified, in particular at the interface with the cathode mixture 92.

[0240] In the anode mixture 82 of the electrochemical cell 60 the anode active material particles are coated with the first solidified electrolyte, and in the cathode mixture 92 of the electrochemical cell 60 the cathode active material particles are coated with the second solidified electrolyte.

[0241] The term "solidified electrolyte" is used here in a simplified manner to express the fact that it is the crosslinking of the crosslinkable composition initially included in the corresponding liquid electrolyte, the electrolyte remaining trapped in the liquid state and forming domains or islands within the polymer matrix with the possibility of ionic exchanges between the different domains or islands, and coating the active materials and the electron-conducting charges.

[0242] Figure 8 illustrates a variant of the electrochemical cell 60, which still includes the same overlay, but which is sealed with the addition of:

[0243] - the conductive varnish layer 66, waterproof and electrically conductive, on the external face of the anode current collector film 81;

[0244] - the other layer of conductive varnish 67, waterproof and electrically conductive, on the external face of the cathode current collector film 82; and

[0245] - the two layers of electrically insulating varnish 68, waterproof and electrically insulating, on the two opposite longitudinal edges of the electrochemical cell 60 (these two layers of electrically insulating varnish 68 initially deposited on the stack 6 having hardened, during exposure to the electron beam(s) 50).

Claims

CLAIMS 1. Method for manufacturing an electrochemical cell (60) of a polymer matrix battery, comprising the following steps: - a first covering step in which an anode current collector film (81) is covered or impregnated with an anode mixture (82) which is in a pasty or semi-liquid state and which contains at least one anode active material dispersed in a first crosslinkable liquid electrolyte containing a first crosslinkable composition, so as to form an anode electrode (83); - a second covering step in which a cathode current collector film (91) is covered or impregnated with a cathode mixture (92) which is in a pasty or semi-liquid state and which contains at least one cathode active material dispersed in a second crosslinkable liquid electrolyte containing a second crosslinkable composition, so as to form a cathode electrode (93); - a third impregnation step during which a separator film (71), electrically insulating and porous, is impregnated with a third crosslinkable liquid or semi-liquid electrolyte (72) containing a third crosslinkable composition, so as to form a pre-impregnated separator film (73); - a stacking step during which the anode electrode (83) and the cathode electrode (93) are stacked against each other, by interposing the pre-impregnated separator film (73), between the anode electrode (83) and the cathode electrode (93), so as to form a stack (6); - a solidification step, after the stacking step, during which the stack (6) is exposed to at least one electron beam so that the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte (72) solidify in mass both in the anode electrode (83), the cathode electrode (93) and the separator film (71), thus forming the polymer matrix electrochemical cell (60).

2. Manufacturing method according to claim 1, wherein the first crosslinkable composition, the second crosslinkable composition and the third crosslinkable composition are similar.

3. Manufacturing method according to claim 1 or 2, wherein the first crosslinkable composition, the second crosslinkable composition and the third crosslinkable composition respectively comprise a first monomer or prepolymer mixture, a second monomer or prepolymer mixture and a third monomer or prepolymer mixture, each comprising monomers or prepolymers or a combination of monomers and prepolymers, wherein the monomers or prepolymers comprise crosslinking functions for solidification of the anode mixture (82), the cathode mixture (92) and the third crosslinkable liquid or semi-liquid electrolyte (72) upon exposure to the at least one electron beam.

4. Manufacturing method according to claim 3, in which the crosslinking functions are chosen from acrylate, methacrylate, vinyl, styrene, isocyanate, acrylamide and methacrylamide functions.

5. Manufacturing method according to any one of the preceding claims, in which the first crosslinkable composition has a mass percentage in the anode mixture (82), which is between 2 and 20%, and for example between 3 and 7%, and the second crosslinkable composition has a mass percentage in the cathode mixture (92), which is between 2 and 20%, and for example between 3 and 7%.

6. A manufacturing method according to any preceding claim, wherein the first coating step involves roll-to-roll deposition or impregnation of the anode mixture (82) onto the anode current collector film (81) such that the anode electrode (83) forms a first continuous strip, the second coating step involves roll-to-roll deposition or impregnation of the cathode mixture (92) onto the cathode current collector film (91) such that the cathode electrode (93) forms a second continuous strip, and the third impregnation step involves continuous impregnation of the separator film (71) with the third crosslinkable liquid or semi-liquid electrolyte (72) such that the pre-impregnated separator film (73) forms a third continuous strip which is interposed between the first continuous strip and the second continuous strip during the stacking step.

7. A manufacturing method according to claim 6, wherein the separator film (71) is continuously unwound from a third reel (710) and continuously impregnated with the third crosslinkable liquid or semi-liquid electrolyte (72) to form the third continuous strip.

8. Manufacturing method according to any one of the preceding claims wherein, in the third impregnation step, the third electrolyte crosslinkable liquid or semi-liquid (72) is impregnated throughout the entire volume of the separator film (71).

9. Manufacturing method according to any one of the preceding claims, in which the stacking step implements a compression of the stack (6), for example by continuous rolling or by a press, before exposing it to the at least one electron beam.

10. Manufacturing method according to claims 6 and 9, in which the compression of the stack (6) is carried out by continuous compression, between two rolling rollers (41), of the first continuous strip, the third continuous strip and the second continuous strip.

11. Manufacturing method according to any one of the preceding claims, comprising a final compression step during which the stack (6) is compressed, for example by continuous rolling or by a press, after having been exposed to the at least one electron beam.

12. A manufacturing method according to any one of the preceding claims, wherein the anode active material comprises anode active material particles having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers, and the cathode active material comprises cathode active material particles having maximum dimensions of between 0.5 and 200 micrometers, and for example between 1 and 20 micrometers.

13. A manufacturing method according to claim 12, wherein the anode active material particles and the cathode active material particles are spherical or substantially spherical shaped particles.

14. A manufacturing method according to any preceding claim, wherein the anode mixture (82) contains first electron-conducting fillers dispersed in the first crosslinkable liquid electrolyte, and the cathode mixture (92) contains second electron-conducting fillers dispersed in the second crosslinkable liquid electrolyte.

15. The manufacturing method of claim 14, wherein the first electron-conducting fillers and the second conductive fillers electrons are charges having at least one nanometric dimension between 1 and 200 nanometers.

16. A manufacturing method according to claim 14 or 15, wherein the first electron-conducting fillers and the second electron-conducting fillers are: - carbon fillers selected from carbon black, carbon nanofibers, titanium nitride-coated carbon nanofibers, carbon nanotubes, graphene powders, and graphene oxide powders; or - non-carbon fillers chosen from metal fibers, metal powders such as carbon fluoride powders, aluminum or nickel powders, conductive metal oxides, conductive polymers, and conductive ceramic powders.

17. A manufacturing method according to any one of claims 14 to 16, wherein the first electron-conducting fillers and the second electron-conducting fillers have mass percentages in the respective anode mixture (82) and cathode mixture (92) which are between 0.1 and 10%, and for example between 0.5 and 5%.

18. A manufacturing method according to any one of the preceding claims, wherein the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte each comprise at least one lithium or sodium salt dissolved in at least one liquid solvent.

19. Manufacturing method according to any one of the preceding claims, in which the first crosslinkable liquid electrolyte and the second crosslinkable liquid electrolyte each comprise at least one surfactant with a mass percentage of between 1 and 5%, and for example between 2 and 4%.

20. Manufacturing method according to any one of the preceding claims, in which the first covering step implements: - unwinding the anode current collector film (81), which is previously wound on a first reel (810); and - covering or impregnating the anode current collector film (81) with the anode mixture (82), as it unrolls.

21. Manufacturing method according to any one of the preceding claims, in which the second covering step implements: - unwinding of the cathode current collector film (91), which is previously wound on a second reel (910); and - covering or impregnating the cathode current collector film (91) with the cathode mixture (92), as it unrolls.

22. Manufacturing method according to any one of the preceding claims, in which the first covering step comprises a first thickness calibration step which consists of a mechanical adjustment of a thickness, called first thickness (El), of the anode electrode (83) before the stacking step.

23. Manufacturing method according to claim 22, in which the first thickness (El) is adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers.

24. Manufacturing method according to claim 22 or 23, wherein the first thickness calibration step is implemented by compressing the anode electrode (83), before the stacking step.

25. A manufacturing method according to claim 24, wherein the anode electrode (83) is compressed by continuous rolling between two rolling rollers comprising a first input roller (13) and a first output roller (14).

26. A manufacturing method according to claim 25, wherein the anode current collector film (81) is continuously fed in on the first inlet roller (13), and the anode mixture (82) is deposited or impregnated on said anode current collector film (81) at this first inlet roller (13) to form the anode electrode (83), this anode electrode (83) being continuously fed between the first inlet roller (13) and the first outlet roller (14) to be compressed and then fed out of the first outlet roller (14).

27. A manufacturing method according to any preceding claim, wherein the second covering step comprises a second thickness calibration step which consists of a mechanical adjustment of a thickness, called second thickness (E2), of the cathode electrode (93).

28. Manufacturing method according to claim T1, in which the second thickness (E2) is adjusted to a value between 10 and 1000 micrometers, and for example between 30 and 500 micrometers.

29. A manufacturing method according to claim T1 or 28, wherein the second thickness calibration step is implemented by compressing the cathode electrode (93), before the stacking step.

30. A manufacturing method according to claim 29, wherein the cathode electrode (93) is compressed by continuous rolling between two rolling rollers comprising a second input roller (23) and a second output roller (24).

31. A manufacturing method according to claim 30, wherein the cathode current collector film (91) is continuously fed in on the second input roller (23), and the cathode mixture (92) is deposited or impregnated on said cathode current collector film (91) at this second input roller (23) to form the cathode electrode (93), this cathode electrode (93) being continuously fed between the second input roller (23) and the second output roller (24) to be compressed and then fed out of the second output roller (24).

32. Manufacturing method according to any one of the preceding claims, in which, during the solidification step, the stack (6) is exposed to at least one electron beam which comprises: - a single electron beam facing one of the anode electrode (83) or the cathode electrode (93), or - two electron beams facing respectively the anode electrode (83) and the cathode electrode (93).

33. Manufacturing method according to any one of the preceding claims, in which the at least one electron beam has an irradiation dose characteristic of between 10 and 100 kGy, and for example between 50 and 80 kGy.

34. Manufacturing method according to any one of the preceding claims, wherein the at least one electron beam has an acceleration voltage characteristic of between 100 keV and 1 MeV.

35. Manufacturing method according to any one of the preceding claims, in which a running speed of the stack (6) has a speed characteristic of between 1 and 500 m / min, and for example between 1 and 30 m / min.

36. A manufacturing method according to any one of the preceding claims, wherein at least one of the anode current collector film (81) and the cathode current collector film (91) is selected from: - a metallic laminated film, for example copper or aluminum, provided with perforations; - a porous metallic composite film based on polymer(s) and metallic fibers assembled to form a non-woven fabric; - a porous carbon composite film based on polymer(s) and carbon fibers assembled to form a non-woven fabric, the carbon fibers having optionally undergone pretreatment to improve their electronic and thermal conductivities; - a porous film based on carbon fibers assembled to form a non-woven fabric, the carbon fibers having possibly been pre-treated to improve their electronic and thermal conductivities.

37. Manufacturing method according to claim 36, wherein the perforations of the metallic laminated film have maximum dimensions of between 0.5 and 2 millimeters and are distributed with a density of between 2 and 10 perforations per cm2.

38. Manufacturing method according to claim 36, wherein the pretreatment comprises depositing on the carbon fibers a pretreatment layer based on titanium nitride or titanium carbide or titanium nitride and carbide, said pretreatment layer having a thickness of between 100 and 1000 nanometers.

39. Manufacturing method according to any one of the preceding claims, in which the anode current collector film (81) comprises an internal anode face on which the anode mixture (82) is deposited or impregnated during the first covering step, and an external anode face, opposite the internal anode face, where said external anode face is covered or impregnated beforehand with a layer of conductive varnish (66) which is waterproof and electrically conductive; and the cathode current collector film (91) comprises an internal cathode face on which the cathode mixture (92) is deposited or impregnated during the second covering step, and an external cathode face, opposite the internal cathode face, where said external cathode face is covered or impregnated beforehand with another layer of conductive varnish (67) which is waterproof and electrically conductive.

40. Manufacturing method according to claim 39, in which the conductive varnish layer (66) and the other conductive varnish layer (67) each have a thickness less than or equal to 30 micrometers, for example between 5 and 30 micrometers.

41. A manufacturing method according to any one of the preceding claims, wherein the first covering step and the second covering step are carried out in parallel.

42. Manufacturing method according to any one of the preceding claims, in which the stack (6) has two opposite longitudinal edges, and the manufacturing method comprises a step of applying electrically insulating varnish, after the stacking step and before the solidification step, during which two layers of electrically insulating varnish (68), waterproof and electrically insulating, are deposited respectively on the two opposite longitudinal edges of the stack (6).

43. A manufacturing method according to claim 42, wherein the two layers of electrically insulating varnish (68) harden upon exposure to the at least one electron beam during the solidification step.

44. A manufacturing method according to claim 42 or 43, wherein the anode current collector film (81) has two opposite longitudinal edges (811) defining between them a width (L81) of the anode current collector film (81), and the anode mixture (82) is deposited or impregnated onto said anode current collector film (81), during the first covering step, to form a strip having a width (L82) less than the width (L81) of the current collector film anode (81), thus leaving the two longitudinal edges (811) of the anode current collector film (81) uncovered and unimpregnated with the anode mixture (82), the cathode current collector film (91) has two opposite longitudinal edges (911) defining between them a width (L91) of the cathode current collector film (91), and the cathode mixture (92) is deposited or impregnated on said cathode current collector film (91), during the second covering step, to form a strip having a width (L92) less than the width (L91) of the cathode current collector film (91), thus leaving the two longitudinal edges (911) of the cathode current collector film (91) uncovered and unimpregnated with the cathode mixture (92), so that the two opposite longitudinal edges of the stack (6) are devoid of the anode mixture (82) and the cathode mixture (92) before the step of applying the electrical insulating varnish.

45. Manufacturing method according to any one of the preceding claims, in which the active anode material is chosen from anode materials, used alone or in combination, based on: - carbon, such as graphite, - silicon, - carbonaceous silicon or lithiated silicon, - transition metals or transition metal alloys, - composite materials combining transition metals and carbon, - lithium metal, - sodium metal, - lithium titanate, - aluminum, or magnesium, or tin, or zinc.

46. ​​Manufacturing method according to any one of the preceding claims, in which the active cathode material is chosen from cathode materials, used alone or in combination, based on: - Nickel Manganese Cobalt lithiated, - Nickel Cobalt Lithium aluminum, - Lithium iron phosphate, - Lithium Cobalt Oxide lithiated, - Manganese oxide lithium, - sulfur-carbon composite in the presence of a lithiated anode material, - lithium sulfide, - sodium alloy, such as with Na3V2(PO4)2F3.

47. Manufacturing method according to any one of the preceding claims, in which the first covering step, the second covering step, the stacking step and the solidification step are carried out in an anhydrous atmosphere, and for example in an argon or carbon dioxide atmosphere.

48. Installation for manufacturing an electrochemical cell (60) of a polymer matrix battery, comprising the following stations: - a first covering station (1) comprising a first distributor (10) of an anode current collector film (81), a first reservoir (11) containing an anode mixture (82) which is in a pasty or semi-liquid state and which contains at least one anode active material dispersed in a first crosslinkable liquid electrolyte containing a first crosslinkable composition, and a first covering unit (12) for covering or impregnating the anode current collector film (81) with the anode mixture (82) so as to form an anode electrode (83); - a second covering station (2) comprising a second distributor (20) of a cathode current collector film (91), a second reservoir (21) containing a cathode mixture (92) which is in a pasty or semi-liquid state and which contains at least one cathode active material dispersed in a second crosslinkable liquid electrolyte containing a second crosslinkable composition, and a second covering unit (22) for covering or impregnating the cathode current collector film (91) with the cathode mixture (92) so as to form a cathode electrode (93); - a third impregnation station (3) comprising a third distributor (30) of a separator film (71), electrically insulating and porous, and an impregnation unit (32) for impregnating the separator film (71) with a third crosslinkable liquid or semi-liquid electrolyte (72) so as to form a pre-impregnated separator film (73); - a stacking station (4) for stacking the anode electrode (83) and the cathode electrode (93), with an interposition of the pre-impregnated separator film (73) between the anode electrode (83) and the cathode electrode (93), to form a stack (6); - a solidification station (5), at the outlet of the stacking station (4), comprising at least one electron beam generator (50) for exposing said stack (6) to at least one electron beam so that the first crosslinkable liquid electrolyte, the second crosslinkable liquid electrolyte and the third crosslinkable liquid or semi-liquid electrolyte (72) solidify in mass both in the anode electrode (83), the electrode cathode (93) and the separator film (71), thus forming the polymer matrix electrochemical cell (60).

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