FR3109673A1 - Component with active material retention reliefs for electrical energy accumulator, electrical energy accumulator using the component and manufacturing method - Google Patents

Abstract

The invention relates to a component (1) for an electric accumulator, comprising: - a substrate (10) comprising at least one electrically conductive layer (30) forming a current collector, - at least one separator film (50), - at least one layer (40) of particles of active electrode material, in electrical contact with the current collector layer, and arranged between the substrate and the separator film. According to the invention: - the layer of particles of active electrode material is devoid of binder, - At least one of the substrate and of the separator film is bristling with retention reliefs (24) of the layer of particles of active electrode material. The invention also relates to a method of making such a component and to an energy storage cell comprising one or more of such components. Applications to accumulators and supercapacitors of the lithium-ion, lithium metal, lithium-sulfur, lithium air and sodium-ion type in particular. Figure 6

Description

Component with active material retention reliefs for an electrical energy accumulator, electrical energy accumulator using the component and manufacturing method.

The present invention relates to components intended for the manufacture of electrical energy accumulators and in particular accumulators of the lithium-ion, lithium-sulfur, lithium metal, lithium-air, sodium-ion or sodium metal type, as well as their system electrochemical based on ion transport. The components can be used to manufacture batteries or supercapacitors.

The term "components" means constituent parts of an electrical energy accumulator which can be manufactured separately and assembled to form one or more accumulator cells. These are in particular components comprising at least one layer of active material. The invention also relates to a method of manufacturing the components. Finally, it relates to an electrical energy accumulator cell, as well as an electrical energy accumulator, comprising at least one of the aforementioned components.

The invention finds applications in the technical field of the manufacture of batteries and/or electric capacitors.

In the following description, the reference to batteries or to battery cells is understood as not excluding the use of the components of the invention for producing energy accumulators in the form of supercapacitors.

State of the prior art

Lithium battery cells include a positive electrode, a negative electrode, an electrolyte-permeable electrical insulating separator disposed between the positive electrode and the negative electrode, and an electrolyte impregnating the electrodes and the separator.

In the remainder of the description, the term “positive, respectively negative” electrode is understood to mean part of an electrical energy accumulator essentially comprising a positive active material, respectively a negative active material.

In the case of a lithium energy accumulator, the positive active material may comprise a lithiated metal oxide capable of constituting a reservoir of lithium ions. The negative active material may comprise, for example, graphite capable of inserting lithium ions. The positive electrode and the negative electrode are associated with electrically conductive layers, generally metallic, serving as an electrical interface with the active electrode material. These layers are referred to as current collector.

In the case of a lithium energy accumulator, the current collector associated with the positive electrode may comprise an aluminum layer in contact with the positive active material. Similarly, the current collector associated with the negative electrode may comprise a layer of copper in contact with the negative active material.

The insertion of lithium ions into the active material of the negative electrode, occurring at the time of charging of the electrical energy accumulator, has the effect of increasing the volume of the active material. Similarly, during the discharge of the electrical energy accumulator, the lithium ions are inserted into the active material of the positive electrode and also modify its volume. The repetition of a large number of charging and discharging cycles induces volume variations in the active materials during each cycle. This has the effect of modifying and disorganizing the structure of these active materials, but also of modifying the contact between the active materials and the electrode collector. As a result, the structure and electrical characteristics of the electrodes change over time, leading to a reduction in performance in the storage and return of electrical energy by the accumulator.

In order to reduce the alteration of the active electrode material, it is possible to use an active electrode material in the form of small-sized particles, i.e. powders or short fibers. These are, for example, micrometric or even nanometric particles.

The pulverulent nature of the micrometric active material avoids, or at least reduces the progressive deterioration of the electrodes during charging or discharging cycles. On the other hand, it increases the difficulty of manufacturing energy accumulators. In particular, the pulverulent nature of the active material, and/or its form factor, such as short fibers for example, poses problems of maintaining this material on current collectors for the formation of electrodes. It also poses problems of maintaining the electrodes and problems of electrical contact with the current collectors associated with the electrodes.

These difficulties can be overcome by adding a binder to the active ingredient. The binder has, in this case, a dual function of structuring the active material within the electrode and facilitating its attachment to the current collectors. The binder is preferably a polymer, for example polyvinylidene fluoride (PVDF). The amount of binder added to the active material powder can vary from 2 to 20 percent by mass of the total dry matter of the electrode.

The binder can be combined with a solvent so as to give the active material a liquid or semi-liquid consistency when coating the current collectors. The liquid or semi-liquid consistency makes it possible to deposit the active material in the form of a thin layer, comparable to a layer of ink, by implementing deposition techniques comparable to printing or screen printing techniques.

After deposition, drying in the oven makes it possible to evaporate the solvent used so that the binder solidifies by fixing the particles of active material between them and in contact with the collectors.

Also, after its deposition, the active material can undergo a calendering operation consisting in compacting it so as to reduce and calibrate its thickness while controlling the porosity of the electrode. This operation also has the effect of improving the electrical conductivity in the layer of active material by reinforcing the contact between the particles and with the current collector.

Another technique for fixing the active material consists in using a porous structure in which particles of active material are disseminated. Reference may be made on this subject to document US9077041.

While the use of active material in the form of powders of fine particles and/or with a form factor such as short fibers appears to be promising for improving the electrical capacity and the durability of electrical energy accumulators, the invention proceeds from the identification of a certain number of limits or technical difficulties. These are, in particular, technical difficulties relating to the presence of a large quantity of binder inherent in this technology.

The binder at least partially coats the particles of active material. It thus constitutes a hindrance in particular for the diffusion, or the percolation, of the electrolyte in the electrodes. This discomfort is all the more significant as the layer of active material is thick and highly compacted. However, poor percolation of the electrolyte has the effect of reducing the efficiency of the active material and constitutes a limit for the full recovery of the electrical capacity of the accumulator.

Moreover, the binder, when it partially or completely coats the particles of active material, tends to create, between the particles, a barrier with a certain effect of both electrical and ionic insulation. Without entirely preventing the circulation of electrons between the particles of active material in contact, step by step as far as the current collector, the relative insulation effect of the particles has the consequence of increasing the internal electrical resistance of the accumulators by energy. This can result in deleterious effects of heating by Joule effect, in particular under high intensity charging or discharging currents. In the same way, the fact that the particles of active material are surrounded by binder, harms the percolation of the ions conveyed in the electrolyte with the particles of active material. This results in a reduction in the electrical capacity and an impossibility of delivering high currents in such energy accumulators.

For these reasons, the use of a binder limits the possibilities of producing thick electrodes.

The invention proposes a constituent component for an electrical energy accumulator and, by extension, an electrical energy accumulator making it possible to overcome the aforementioned technical difficulties.

The invention also proposes a method for producing such a component.

An object of the invention is in particular to improve the percolation, that is to say the diffusion of the electrolyte, and therefore the circulation of the ions (lithium, sodium, etc.) conveyed by the electrolyte, in the active material of the electrodes of an energy accumulator.

Another object of the invention is to improve the electrical conduction inside the active material, and from the active material towards the current collectors of the electrical energy accumulators. It thus aims to reduce the internal resistance of electrical energy accumulators and their heating by Joule effect during charging and discharging phases. Thus, higher currents can be conveyed without penalizing the life of the energy accumulators.

Yet another object of the invention is to increase the thickness of the active material of the electrodes and thus to improve the mass ratio between the active material of the electrodes on the structural inactive material of the electrical energy accumulators. Structural inactive material of electrical energy accumulators means the material of all parts that have no direct active function in the storage of electrical energy. It is, for example, the enclosure or the casing of the electrical energy accumulators, the current collectors, the separator or even the electrical conductors used for the interconnection of accumulator cells. A better ratio of the mass of active material of electrodes to the mass of structural inactive material makes it possible to improve the specific electrical capacity of electrical energy accumulators.

Another object of the invention is to provide a component, intended for the production of electrical energy accumulators, which is both flexible and resistant, and capable of being rolled up as needed.

Another object is to propose the production of such a component with a large surface, without risking an unexpected deformation, in particular the deformation of a separating film of the component. This also makes it possible to reduce the risk of a short circuit between the electrodes.

Yet another object is to provide a method for manufacturing a substrate, and a component in accordance with the invention, all or part of the steps of which can be carried out continuously from roll to roll.

To achieve these aims, the invention relates more specifically to an electrical energy accumulator component comprising:
- a substrate provided with at least one electrically conductive layer forming a current collector,
- at least one separating film,
- At least one layer of electrode active material particles (of a type compatible with lithium, respectively with sodium), in electrical contact with the current collector layer, and placed between the substrate and the separator film.
According to the invention:
- the layer of electrode active material particles is devoid of binder,
- at least one of the substrate and of the separator film is bristling with reliefs for retaining the layer of active electrode material particles, the reliefs being independent of each other and extending between the substrate and the separator film.

It is considered that the substrate, respectively the separator film, is bristling with retention reliefs of the layer of particles of active material when the retention reliefs extend substantially perpendicular to a face of the substrate, respectively of the separator film, to which they are fixed.

The reliefs are considered to be independent of each other when they do not touch. The reliefs are spaced from each other in a plane parallel to the substrate or to the separator film. The retention reliefs define, with the substrate and the separating film, volumes containing the particles of active material. Within the component, the retention reliefs do not constitute partitioning: the volumes communicate with each other and in no way hinder the percolation and circulation of the electrolyte ions of an electrical energy accumulator cell. using the component. A particular retention relief, referred to as "lateral retention relief" in the remainder of the description, can however be formed from a continuous line and surround all of the other retention reliefs to form a basin forming a barrier to the material. active in the component.

A component in accordance with the invention can be used for assembling electrical energy accumulators, and in particular accumulators of the lithium-ion, lithium-metal, lithium-sulfur or sodium-ion and sodium-metal type. In this case, the active electrode material is of a type compatible with lithium, respectively with sodium. Examples of active materials are indicated below.

The substrate is preferably a thin film-like substrate. It has a dual function of active material support and current collector. The substrate can also have a sealing wall function for the constitution of a battery cell containing an electrolyte. This aspect is further discussed later.

The substrate comprises one or more conductive layers forming a current collector with which the active electrode material is in electrical contact. In the rest of the description, and unless otherwise specified, the singular mention of a conductive layer forming a current collector does not prejudge the possibility of implementing several electrically conductive layers, or electrically conductive films, forming a current collector.

Different configurations of the layer forming the current collector are possible. In order to optimize the electrical contact surface with the active material, the conductive layer forming a current collector can extend over a main face of the substrate receiving the active material. In the case of a component intended for the production of a lithium-ion or sodium-ion type energy accumulator, a layer of copper, a layer of stainless steel, a layer of titanium or a film of conductive polymer electrical, forming a current collector can be associated with the negative electrode. Furthermore, a layer of aluminum, stainless steel, nickel, titanium or electrically conductive polymer can also be associated with the positive electrode. The substrate can receive active electrode material on one of its main faces or on its two opposite main faces. In the latter case, the bipolar substrate can preferably receive active materials of opposite polarities, that is to say electrodes of opposite polarities, on its two opposite faces. In the rest of the description, the mention of the layer of active material in the singular does not prejudge the fact that the substrate can carry an electrode respectively on its two opposite faces, or on a single face only.

The active material can be in the form of particles, powder or short fibers. It can also incorporate electrically conductive particles whose function is to improve the electrical connection of the particles of active material with the current collector. Electrically conductive particles can also be used to improve the mechanical structure of the electrode as well as the electrical contact of the particles of active material between them. These are, for example, carbon nanotubes, bundles of carbon nanotubes, graphite fibers, carbon fibers, carbon black or a graphene powder. Thus the terms “layer of particles of active material” are understood as designating a layer comprising particles of active material, but which may also include other particles improving the electrical interconnection of the particles of active material. However, it does not contain a binder. In other words, the layer of particles of active material does not contain any added material coating the particles and fixing the particles to each other so as to agglomerate them.

According to an important characteristic of the invention, the component comprises reliefs for retaining the active material. These are the retention reliefs, already mentioned, initially formed on the substrate. A main function of these reliefs is to ensure the maintenance and the cohesion in the component of the active material. This function is important due to the absence of a binder ensuring the agglomeration of the particles. The retention reliefs in particular prevent the layer of active material from detaching from the substrate and from the current collector, whether during the manufacture of the energy accumulators or during charging and discharging cycles of an accumulator comprising the making up.

During charging and discharging cycles of an energy accumulator, the active material increases in volume or decreases in volume depending on the insertion or deinsertion of the ions. This phenomenon manifests itself in particular on the negative electrode in the case of a silicon accumulator, but also on the positive electrode in the case of a sulfur accumulator. The retention reliefs may have other additional functions. One of these functions can be to bond the release film to the substrate while preventing its deterioration due to the deformation of the active material. In this case, the retention reliefs can be provided with a capacity for elastic deformation sufficient to accompany deformation or swelling of the layer of active material during the charging of an accumulator provided with the component, and a return to a thickness weakest of the component during the discharge.

The retention reliefs also make it possible to obtain a uniform maintenance of the separator film on the substrate, due to their distribution. Proper retention of the separator film allows large components to be produced. The components of the invention can thus have a main face with a surface that can exceed several square meters with lengths of several meters. It is thus possible to increase the storage capacity of electrical energy accumulator cells using such components. In an accumulator battery, this makes it possible to avoid parallel coupling of several electrical energy accumulator cells of lower capacity, while benefiting from a higher specific capacity as well as a charging current and significant discharge. The cohesion of the separator film and the substrate, ensured by the retention reliefs, improves the hold of the component without harming its flexibility. The component, or an electrical energy accumulator incorporating one or more components of the invention, can thus be rolled up and lend themselves to possible packaging in a rolled up form.

Another function of the retention reliefs can be to facilitate the control of the thickness of active material, by serving as a thickness gauge during a leveling of the active material at the time of its deposition on the substrate.

The retention reliefs preferably extend through the layer of particles of active material over its entire thickness between the substrate and the separator film. However, it is possible for the retention reliefs, or for some of the retention reliefs, to extend only over part of the thickness of the layer of particles of active material.

The retention reliefs can be attached to the substrate, respectively to the separator film, or can be formed in one piece with at least one of the substrate and the separator film, for example by thermoforming these supports. It is considered that the retention reliefs are formed in one piece with the substrate, respectively with the separator film, when the substrate, or the separator film, as a whole is for example thermoformed or when a layer of material forming part of the substrate is thermoformed so as to form the retention reliefs.

According to a particular embodiment of the component, the substrate may comprise a main polymer film and the retention reliefs may be formed in one piece with the main polymer film. The main polymer film can be associated with a metallic film. It can in particular be glued to a metallic film. It can also be coextruded with a metal film or formed (coated) on a metal film. The bonding of the main polymer film to the metal film can take place in particular by means of an electrically conductive adhesive layer.

The main polymer film, as well as the adhesive layer, are preferably electrically conductive, so as to form a current collector with the metallic film which is also electrically conductive. A method of manufacturing such a component is described in more detail in the following description.

When the retention reliefs are formed in one piece with the substrate, the substrate may comprise at least one surface layer of heat-sealable or heat-bondable material. This layer of heat-sealable or heat-adhesive material covers the retention reliefs or, at the very least, a top part of the retention reliefs. It is used to fix the separating film on the substrate.

According to another particular embodiment of the component, the latter may comprise retention reliefs made of a heat-weldable or heat-bondable material, fixed to the substrate.

The retention reliefs are preferably formed on the substrate insofar as the substrate generally has better mechanical strength than the separator film. The separator film is an electrically insulating film but permeable to an electrolyte and to the ions contained in an electrolyte capable of being used in an electrical energy accumulator comprising the component. The separator film is, for example, a polymer film, based on polypropylene and/or polyethylene, or a cellulose film. It can also be a composite film. The separator film may comprise, for example, at least one layer of porous ceramic deposited on a polymer film. It can also be formed from several layers of polymer, for example a layer of polyethylene sandwiched between two layers of polypropylene. The separator film may however comprise a part of the retention reliefs in addition to those arranged on the substrate.

When the retention reliefs are formed on the substrate, they can be arranged, for example, on the electrically conductive layer forming the current collector. In particular, they can be formed on such a layer covering a main face of the substrate intended to receive the layer of particles of active material. Conversely, a conductive layer forming a current collector can also cover the main face of the substrate and the retention reliefs.

The term heat-sealable or heat-bondable material is understood to mean a material, such as heat-sealing, capable of being completely or partially melted by subjecting it to a source of heat, and capable of resuming a solid consistency at the operating temperature of electric accumulators. The material of the retention reliefs is said to be "heat-bondable" when it is capable of being heat-bonded to the substrate and "heat-weldable" when it can be welded to the substrate, by the simultaneous application of heat and pressure. of contact.

Preferably, the retention reliefs can be made of a thermal adhesive based on ethylene-vinyl acetate (EVA), polyolefin or thermoplastic elastomers (TPE). The thermoglue can also include paraffins or waxes mixed with ethylene-vinyl acetate or polyolefin. The use of thermal glue advantageously makes it possible to form the hot retention reliefs with a deposition robot comparable to an inkjet printer, or with a 3D printer, depositing the reliefs in liquid or semi-liquid form.

Before the formation of the heat-bonded retention reliefs, either directly on the substrate, or on an electrically conductive layer forming a current collector, the surface receiving the retention reliefs can advantageously be subjected to a plasma treatment, a corona treatment or chemical treatment. The function of such a treatment is to improve the adhesion of the retention reliefs and to perpetuate their fixation over the long term.

The production of all or part of the retention reliefs in thermal adhesive facilitates their bonding both to the substrate and to the separating film. The thermoadhesive reliefs can also constitute spacers, or spacers, between the substrate and the separator film and contribute to the attachment of the separator to the substrate. The separator, the substrate and the retention reliefs then constitute a network of cells in mutual communication and containing the particles of active material. The particles of active material are trapped in the cells.

The use of a thermal glue is also advantageous because of its elasticity and its power of elongation, to accompany the modifications of the thickness of the layer of active material during the charging and discharging cycles of an accumulator. energy receiving the component. The elongation of the retention reliefs depends on the elasticity of the heat seal retained. It can reach up to 300 percent of the initial length or height of the retention reliefs connecting the substrate to the separator. This elasticity ensures the compatibility of the component with active materials with a high expansion coefficient. This is the case, for example, when silicon is used for the negative electrode (anode) instead of graphite or together with graphite.

As a supplement, the function of fixing the separating film can also be ensured by specific spacers, distinct from the retention reliefs. These are, for example, the rims of one or more troughs of the substrate, or even spacers, on which the separating film is glued.

Different forms of retention reliefs can be envisaged. In particular, the retention reliefs may comprise at least one of frustoconical reliefs, linear reliefs and lateral reliefs. The frustoconical reliefs are preferably in the form of small spikes, the larger base of which is connected to the support on which they are initially formed.

Optionally linear or lateral retention reliefs having an elongated shape may also be provided. They can be used, for example, to form at least one basin on the substrate, or slides favoring the guiding of a squeegee for leveling off the layer of particles of active material when it is placed on the substrate. This aspect is described below. The side reliefs for their part form a perimeter delimiting a basin to contain the active material on the substrate.

When the reliefs are tapered, they may have a diameter of between 0.2 and 1.2 mm at their base, and a diameter of between 0.1 mm and 0.4 mm at their top, for a height of 0.2 to 0. .8mm. Furthermore, the frustoconical reliefs may have, between neighboring reliefs, an average spacing of between 5 and 20 mm. The spacing between the retention reliefs is understood in the plane of the support on which they are formed.

According to one particular embodiment of the component of the invention, the substrate may have at least one depression on at least one of its faces. In this case, the cuvette is covered by the separating film. The retention reliefs and the layer of particles of active material are then located inside the bowl between the substrate and the separating film.

In this embodiment, the walls of the cuvette make it possible, if necessary, to retain the particles of active material when they are placed on the substrate, in particular in the case of their placement in the form of liquid or semi-liquid. liquid due to the addition of a carrier liquid, for example a solvent. The tops of the walls of the bowl can also be used for an operation of leveling off the layer of particles of active material or even for fixing the separator.

Preferably, the depth of the bowl, or the height of the edges of the bowl, measured from the bottom of the bowl, can be equal to the height of the retention reliefs.

When the component comprises several cups, these preferably communicate with one another. Thus, the cuvettes do not create any discontinuity in the layer of particles of active material.

According to another particular embodiment of the component of the invention, which is not exclusive of that indicated above:
- the substrate has a first main face and a second main face opposite the first main face,
- the first main face and the second main face are provided with retention reliefs,
- the first and the second face carry respectively a layer of particles of positive electrode active materials and a layer of particles of negative electrode active materials,
- A separating film respectively covers the layer of active electrode material and the retention reliefs of the first and of the second main face.

As already indicated, the separator film can be attached to the retention reliefs. The retention reliefs are essentially frustoconical reliefs. However, the first main face and the second main face can also comprise one or more lateral retention reliefs.

Such a substrate, carrying two electrodes of opposite polarity, is then qualified as bipolar. It may be common to two energy accumulators assembled in series in the same accumulator battery.

As indicated above, the substrate comprises one or more electrically conductive layers, for example layers of metal and/or of electrically conductive polymer, forming a current collector. The layer of particles of active material is in electrical contact with the layer or layers forming the current collector.

Also, the electrically conductive layer forming a current collector can be a layer covering a face of the substrate receiving the retention reliefs.

In particular, in the case of a bipolar support, conductive layers forming a current collector can respectively cover all or part of the first and the second main face of the substrate.

It should be specified that the retention reliefs can be formed on the electrically conductive layer forming the current collector or can be covered by this layer.

According to yet another possible embodiment of a component according to the invention, and in particular a bipolar component,
- the substrate may be a film comprising a central electrically conductive layer sandwiched between a first layer of polymer receiving the retention reliefs and a second layer of polymer,
- the electrically conductive layer forming a current collector can cover one face of the first layer of polymer receiving the retention reliefs,
- the electrically conductive layer forming a current collector can be electrically connected to the central electrically conductive layer, by connection wells passing through the first polymer layer.

The central electrically conductive layer can be a metal layer, and in particular an aluminum layer.

In the case of such a composite substrate, the central electrically conductive layer can be considered as also forming part of the current collector, knowing that it is in electrical contact with the electrically conductive layer covering the first layer of polymer and forming a collector current. The central electrically conductive layer, in particular when it is an aluminum layer, can also serve as a sealing barrier. This is the case when the component, used for making an energy accumulator cell, also constitutes a wall of the cell. Sealing is understood in particular with respect to an electrolyte capable of coming into contact with the electrode carried by the component.

According to yet another possible embodiment of the bipolar component,
- the substrate may be a film comprising a central conductive layer sandwiched between a first layer of polymer receiving the retention reliefs and a second layer of polymer,
- an electrically conductive layer forming a current collector can cover one face of the first layer of polymer receiving the retention reliefs,
- the first layer of polymer receiving the retention reliefs can be electrically conductive,
- the electrically conductive layer forming a current collector can be electrically connected to the central electrically conductive layer, via the first layer of electrically conductive polymer receiving the retention reliefs.

In this embodiment, the electrically conductive polymer layer serving as a support for the retention reliefs also serves as an electrical connection between the current collector layer and the central conductive layer of the substrate. All of these conductive layers participate in the current collector function.

The invention also relates to an electrical energy accumulator cell, and in particular a cell of the lithium-ion, lithium metal, lithium sulfur, sodium metal or sodium-ion type. The cell comprises at least a first component as described above, provided with a layer of positive electrode active material particles, and at least a second component provided with a layer of negative electrode active material particles. The first component is superimposed on the second component and the release film of the first component is in contact with the release film of the second component.

Alternatively a single release film can be shared between the two components.
In this case, the cell comprises at least a first component as described previously, provided with a layer of positive electrode active material particles, at least a second component provided with a layer of active material electrode particles negative, the first component being superimposed on the second component and the layer of particles of active material of the first component is separated from the layer of particles of active material of the second component by a separator film common to the first and to the second component.

The accumulator cell, in a simple embodiment, may comprise only two components. In this case, the layers of active material of the two components form the positive and negative electrodes of the accumulator. An accumulator cell can also comprise a larger stack of components, and in particular of bipolar components. It is then similar to an accumulator battery with cells coupled in series and/or in parallel.

The components can be located inside a sealed enclosure containing a liquid electrolyte, in the form of a gel or in the form of a polymer. However, and advantageously, the substrates of the components can also be used to directly constitute a sealed enclosure of the cell.

In this case, the substrate of the first component and the substrate of the second component may respectively have a peripheral zone devoid of active electrode material, and of electrically conductive layers, and a seal may connect the substrate of the first component to the substrate of the second component in the peripheral zone. In this case, the substrate of the first component and the substrate of the second component form, with the seal, a sealed enclosure of the cell.

The sealing joint can also be a joint attached to the substrates in the peripheral zone and welded or glued to the substrates.

Alternatively, the seal can be formed directly from the substrates.

Indeed, according to a particular possibility of implementation:
- the substrate of the first component and the substrate of the second component each comprise at least one layer of electrically insulating thermofusible polymer,
- the peripheral zone is devoid of a conductive layer, and of active electrode material,
- The sealing joint is a solder joint between the layer of thermofusible polymer of the substrate of the first component and the layer of thermofusible polymer of the substrate of the second component.

By thermofusible polymer is meant a polymer which can be welded by the simultaneous application of heat and pressure. The sealing joint can then be produced by applying pressure to a heating frame in the peripheral zone of the substrates, in which the layers of thermofusible polymer of the two components face each other.

According to another possibility, a sealing joint can also include a thermoglue joint, that is to say one or more strips of thermoglue. A thermoglue of the same type as that indicated for the retention reliefs can be used.

The invention finally relates to an electrical energy accumulator, for example of the lithium-ion lithium-metal, lithium-sulfur, sodium-metal or sodium-ion type, comprising at least one cell of the type indicated above and an electrolyte contained in the airtight enclosure of the cell.
The electrolyte can be placed between the separators of the components before their assembly. This is, for example, a layer of electrolyte gel or polymer electrolyte capable of diffusing into the separator sheets and into the electrodes of the components. The electrolyte, and in particular a liquid electrolyte, can also be put in place after the partial sealing of the cell. In this case, the filling can take place through a cannula provided for this purpose. The passage of the cannula can be sealed after filling, performing the final sealing of the cell.

Table I, below, gives some examples of materials that can be used for the production of a positive electrode and a negative electrode as well as for the production of the conductive layers forming the current collector of a component as described, as well as examples of electrolyte usable in an energy accumulator using these components. The examples are given for accumulators of the lithium type.

Accumulator type lithium battery or cell super capacitor Material of the conductive layer forming the current collector
(negative electrode) - Copper,
- Silicon carbide,
- Titanium
- Stainless steel
-Nickel - Aluminum
- Stainless steel
- Copper Material of the conductive layer forming the current collector (positive electrode) - Aluminum,
- Money,
- Gold
-Nickel
- Titanium
- Stainless steel - Aluminum
- Stainless steel
- Copper Active electrode material (negative electrode or anode) - graphite,
- Silicon,
- Titanium in the form Li ₄ Ti ₅ O ₁₂
- Lithium metal Graphite
Graphene
Graphene oxides
Activated carbon (meso/micro and macro porous, biomass derivatives…)
Carbon nanotubes (single-walled (SWCNT) and multi-walled (MWCNTs) nanotubes)
Conductive polymers (polyaniline, polypyrrole, etc.)
Metal oxides: nickel oxide (NiO), cobalt oxide (Co ₃ O ₄ ), ruthenium oxide (RuO ₂ ), manganese dioxide (MnO ₂ ), iridium oxide (IrO ₂ )
Family of cobalt sulphides (Co ₃ S ₄ , CoS ₂ , Co ₉ S ₈ , Co _1-x S, Co _x S _y ) Active electrode material (positive electrode or cathode) -nickel, manganese, lithium cobalt (LNMC),
-lithium manganese oxide (LMO),
-lithium nickel-cobalt-aluminum oxide (LNCA),
-lithium cobalt oxide (LCO), lithium iron oxide (LFP)
Lithium sulphide (Li ₂ S)
Sulfur
- Sodium Symmetrical systems (identical negative and positive materials)

Hybrid SCs:
Metallic oxides (to the positive) Electrolyte (salts) LiPF6, LiTFSi
LiTDI
LiClO ₄
LiTf Organic electrolytes:
Tetraethylammonium tetrafluoroborate (TEABF ₄ )

Aqueous electrolytes:
KOH, _H2SO4 , _{Na2SO4 , Li2SO4} , _K2SO4 , _KCl , _NaCl , _HClO4 , _NaOH Electrolyte (solvents) Ethylene carbonate (EC)
Dimethyl carbonate (DMC)
Propylene carbonate (PC)
Ethers: TEGDME, DME, PEGDME
1,3 dioxolane
1,4 dioxane
Sulfolane
THF Organic: Acetonitrile
Propylene carbonate (PC)

The invention finally relates to a method of manufacturing a component for an electrical energy accumulator as described above. The process comprises the following successive steps:
a) the supply of a substrate comprising at least one face provided with an electrically conductive layer forming a current collector and with retention reliefs,
b) the coating of said face with a layer of particles of active electrode material,
c) the leveling off of the layer of particles of active material at the level of the retention reliefs,
d) fixing to the retention reliefs of a separating film covering the layer of particles of active material.

The method can be completed, during step c) or at the end of step c), by compacting the layer of particles of active material.

Preferably, the substrate retention reliefs have a uniform height. The height of the retention reliefs has good uniformity when the retention reliefs are formed by stamping or thermoforming the substrate.

If this is not the case, the method may include, before step b) of packing, an operation to standardize the height of the retention reliefs.

The standardization of the reliefs of retention can in particular prove to be necessary when the reliefs of retention are reliefs of thermoglue.

In this case, the substrate may be subjected to lamination by a heated roller or to a heated press at a calibrated height so as to regularize the height of the retention reliefs.

The following operation, that is to say the lining of the substrate, consists in depositing active material on the substrate, and in particular on the face or faces of the substrate comprising a conductive layer forming a current collector and reliefs of retention. The active ingredient can be in the form of fine particles, powder or short fibres.

The deposition of the layer of active material can be facilitated by the use of a carrier liquid.

Thus, step b) of packing can advantageously comprise the application, on the face provided with retention reliefs, of a mixture of particles of active electrode material and of a volatile vector liquid. In this case, the method further comprises a stage of evaporation of the vector liquid, subsequent to the leveling off of the layer of particles.

The mixture of the particles of active material and the volatile vector liquid constitutes a sort of semi-liquid ink which, by virtue of its consistency, promotes the deposition of the layer of active material on the substrate and its leveling. It can be prepared in mixers guaranteeing its homogeneity.

The volatile carrier liquid is removed after the formation of the layer of active material so that only the particles of active material remain on the substrate. The volatile liquid can be chosen, for example, from dimethyl sulfoxide (DMSO), n-methyl-2-pyrrolidone (NMP), N-Butyl pyrrolidone (NBP), isopropanol or ethanol. Its elimination, by heating and evaporation can take place under extractor hoods, or under a suction heating press, so as to recycle it.

The operation of leveling off the layer of particles, already mentioned, makes it possible to standardize its thickness. It is considered that the layer is level with the retention reliefs when the layer of particles is leveled with the retention reliefs and in particular with the retention reliefs of greater height.

As indicated above, the retention reliefs preferably have a uniform height or are subjected to an operation consisting in making their height uniform. In this case, the leveling is carried out at a height corresponding to that of the retention reliefs.

The leveling operation can take place, for example, by passing over the surface of the layer of particles a rotating brush forming a squeegee or a vibrating ruler. The squeegee can be supported or guided by the retention reliefs and in particular by a peripheral linear relief surrounding the other retention reliefs.

After the evaporation and the elimination of the vector liquid, the thickness of the deposited layer is reduced so that the reliefs of retention, or at least certain reliefs of retention, protrude from its surface. The retention reliefs protruding from the layer of active material can thus be used to fix the separating film.

After the positioning of the separator film, the layer of particles of active material also undergoes compacting, or calendering. This operation can take place, for example, under a vibrating heating press and/or by passing between two mating rollers of a rolling mill, at least one of which is heated. The fact of compacting the layer of particles makes it possible to reduce its thickness and to bring the particles of active material closer together. Compaction allows the placement of a larger initial quantity of active material while limiting the final thickness of the component. Significant compaction is possible without compromising the subsequent percolation of the electrolyte, due to the absence of binder. It is thus possible to increase the electrical capacity per unit volume of the energy accumulators.

After compacting, the thickness of the layer of active material can be of the order of 100 to 400 micrometers, for example. By way of comparison, the thickness of active material of a traditional component, using a binder for the particles of active material, does not exceed 90 micrometers.

A possible heat treatment during the evaporation of the volatile vector liquid and/or during the compacting of the layer of active material is carried out at a temperature lower than a liquefaction temperature of a thermoglue which can be used for the manufacture of the retention reliefs and a temperature below a softening temperature of a polymer capable of constituting the substrate. The heat treatment is carried out, for example, at a temperature of the order of 40°C to 90°C.

Advantageously, step a) of the method may comprise the formation on one face of the substrate of retention reliefs in an elastic thermo-adhesive. In this case, the separating film can be heat-sealed onto the retention reliefs.

Fixing of the release film can take place under a heated press. This partially melts the part of the retention reliefs protruding from the layer of active material and causes them to stick to the separator film. The porous separator absorbs, like a blotter, a small part of the thermoglue of the retention reliefs, which promotes their attachment to the separator film.

At the end of its fixing, the separating film constitutes a lid which also participates in the retention of the active ingredient on the substrate. In addition, the fixing of the separator on the substrate, by means of the retention reliefs, makes it possible to obtain good robustness and good behavior of the whole of the component thus formed, without affecting its flexible character.

The retention reliefs can be hot-deposited on the substrate by a deposition robot comparable to an inkjet printer. Other deposition machines such as a 3D printer with polymer wire or thermal glue, or machines for depositing microelectronic components, can also be adapted to the formation of retention reliefs.

The retention reliefs can also be formed by rotary screen printing or by hot deformation of a layer of thermal adhesive uniformly distributed on the surface of the substrate in its part which is to receive the active material. The hot deformation of the layer can be carried out by continuous passage (roll to roll) on an engraver roller. The formation of the retention reliefs by rotary screen printing makes it possible to form pointed reliefs, or spikes, of larger size. Furthermore, the treatment of the substrate in a continuous strip (roll to roll) allows the formation of large surface components.

The step of forming the retention reliefs can be used to form other reliefs such as the walls of basins or slender reliefs. In particular, the part of the substrate to receive the active material can be laterally delimited by a wall in the form of a frame, forming a bowl. Such a cuvette is capable of containing the mixture of particles of active material and of vector liquid during the formation of the layer of active material. Linear or slender reliefs, already mentioned, can be formed to serve as a height guide during the leveling operation. All of these reliefs can be formed in heat-sealing and contribute, if necessary, to fixing the separating film.

Step a) of the method, consisting in supplying the substrate, can, if the substrate is not already provided with a conductive layer capable of constituting a current collector, comprise an additional operation of forming such a layer.

In this case, step a) of the method may comprise the deposition of the layer, forming the current collector, on the face of the substrate, provided with the retention reliefs, the layer forming the current collector covering the retention reliefs. The conductive layer forming a current collector can preferably be a metallic layer, for example copper or aluminum.

Furthermore, the conductive layer forming a current collector can be produced by vacuum deposition, and in particular by evaporation or by magnetron sputtering. It is, for example, a layer of aluminum or copper, with a thickness comprised, for example, between 80 and 500 nanometers. Other conductive materials, listed, for example, in Table I, as well as other layer thicknesses are not excluded.

When the conductive layer forming a current collector is formed after the retention reliefs, it covers these reliefs. Also, insofar as the conductive layer is formed by sputtering, precautions are taken, in particular in terms of exposure time, so as not to alter the retention reliefs or the substrate.

Advantageously, the metallized retention reliefs extend the current collector inside the layer of active material and promote electrical conduction by increasing in particular the contact surface between the active material and the current collector. This measure helps to promote an increase in the thickness of the layer of active material and a reduction in the internal electrical resistance.

When the component manufacturing process includes an operation to standardize the height of the reliefs, this operation can preferably be carried out after the deposition of the layer forming the current collector. It is thus possible to take advantage of this operation to eliminate, at least in part, the layer forming the current collector in the top part of the retention reliefs intended for fixing the separator film.

It is also possible to form the conductive layer before the retention reliefs or to form the retention reliefs on a substrate already comprising a conductive layer forming a current collector.

The method of forming the retention reliefs in the form of thermoglue bosses, in the manner described above, is perfectly suitable for the production of single components.

The method can also be adapted for continuous processing. Such processing is also referred to as "roll to roll", i.e. from roll to roll.

In this case, the components, or at least the substrates used in the manufacture of the components, can be formed in the form of very long strips packaged in rolls. The strips can then be cut to complete the components and/or to assemble the components for the formation of electrical energy accumulators.

• la fourniture d’un film polymère principal conducteur électrique,
• la formation sur le film polymère principal des reliefs de rétention. Les reliefs de rétention faisant saillie sur une première face du film polymère principal et la formation des reliefs de rétention ayant lieu par thermoformage du film polymère principal,
• le collage du film polymère principal sur un film métallique, une deuxième face du film polymère principal, opposée à la première face, étant reportée contre le film métallique lors du collage.

Thus, according to one possibility of implementing the process for manufacturing the component of the invention adapted to continuous manufacturing (“roll to roll”), step a) of the process may comprise the following operations:

• providing a primary electrically conductive polymer film,
• the formation on the main polymer film of retention reliefs. The retention reliefs protruding from a first face of the main polymer film and the formation of the retention reliefs taking place by thermoforming of the main polymer film,
• bonding the main polymer film to a metal film, a second face of the main polymer film, opposite the first face, being transferred against the metal film during bonding.

The main polymer film can be a polypropylene film or a polyethylene film filled with carbonaceous electrically conductive particles. It can in particular be loaded with carbonaceous electrically conductive particles, such as carbon nanotubes, and/or conductive carbon black and/or carbon tiles, and/or more or less long carbon fibers which improve its electrical conductivity. and/or its robustness.

The charge of carbonaceous electrically conductive particles of the film can be of the order of 10 to 50% by mass. The thickness of the film can be of the order of 20 to 300 micrometers.

The main polymer film can be rolled up in the form of a spool during its manufacture.

The formation of the retention reliefs is done by thermoforming the main polymer film. The main polymer film, initially flat, is shaped according to a desired profile of retention reliefs. This operation can take place in particular by continuously passing the film through a thermoforming machine. It is equipped, in this case, with a thermoforming die corresponding to the desired relief.

The reliefs protrude from a first face of the main polymer film. This is the face intended to be lined with active electrode material in the manner already described.

A second face of the main polymer film, opposite the first face, comprises recessed reliefs corresponding to the retention reliefs projecting on the first face.

The second side is glued on a metallic film. The metal film may have, together with the conductive polymer of the main polymer film, a current collector function in an electrical energy accumulator using the component. It can also have one of the functions of mechanical strength and sealing.

The metallic film may be, for example, one of aluminum film, aluminum alloy film, titanium film, nickel film, stainless steel film.

This is, for example, a film made of an aluminum alloy of the 6000 or 7000 series with a high elastic limit. The thickness of the film can be chosen, for example from 20 to 80µm. It can also be a film of stainless steel, nickel or titanium with a comparable thickness, from 10 to 100 µm, for example.

Advantageously, the metal film can be lined with a layer of electrically conductive heat seal on one side receiving the second side of the main polymer film during bonding. In this case, the bonding of the main polymer film to the metal film can be hot heat bonding using the heat seal layer.

The thermal adhesive layer filling the metallic film has, for example, a thickness of 3 to 10 μm. It can be a layer of ethylene-vinyl acetate (EVA) or polyolefin. Just like the main polymer film, the thermoglue layer can also be loaded with electrically conductive particles, such as carbon nanotubes or conductive carbon black so as to give it its property of electrical conduction, or so as to improve this property. .

The electrically conductive nature of the thermal adhesive layer ensures good electrical continuity between the main polymer film and the metal film.

The thermoglue is chosen with a liquefaction temperature lower than that of the polymer film and, preferably, sufficiently low so as not to alter the main polymer film during its bonding to the metal film.

The thermoglue can be hot coated on the metallic film.

During the thermal bonding of the main polymer film to the metallic film, these two films can pass between two rollers which press them against each other. The roller in contact with the metal film being a heating roller.

The roller in contact with the main polymer film can also be heated, it can also be provided with holes or a recessed relief receiving the retention reliefs of the main polymer film so as to protect these reliefs from the pressure forces during the passage of the films between the rollers.

The manufacture of the substrate may also include the formation of a layer of thermal adhesive selectively lining a vertex of each retention relief on the first face of the main polymer film. This operation can preferably be carried out after the thermal bonding of the main polymer film to the metallic film.

The thermoglue layer at the top of the retention reliefs may have a thickness of 5 to 10 μm, for example. It is used to fix a separator film on the substrate by heat-sealing during step d) of the manufacturing process of the component described above, that is to say after the filling of the substrate with the particles of active material. The layer of thermoadhesive applied to the top of the retention reliefs is preferably an electrically insulating thermoadhesive layer so as not to risk harming the also electrically insulating character of the separator film. This is, for example, a layer of ethylene-vinyl acetate (EVA) or polyolefin not loaded with conductive particles.

The coating of the retention reliefs with the heat-sealing layer can take place in a continuous coating machine (roll to roll).

At least one of the operations of thermoforming, gluing and forming a heat-sealing layer can be carried out continuously.

More generally, all of the operations for preparing the main polymer film and the metal film, their mutual bonding and the trimming of the top of the retention reliefs with a layer of thermal adhesive can be carried out continuously (roll to roll), by implementing films of the same width wound on rolls. The substrate finally obtained can also be wound on a roll before being made available for the subsequent steps of the method for manufacturing a component according to the invention.

The process for the manufacture of the substrate can be implemented for the production of a unipolar component but also for the production of a component in which the two faces of the substrate carry an electrode of active material. In this case, it is, for example, a bipolar component, with two electrodes of opposite signs.

With a view to producing such a component, the method may comprise the formation of a first substrate and a second substrate, each substrate comprising a main polymer film with retention reliefs, and a metal film bonded to the polymer film main, and the bonding of the first substrate on the second substrate by means of the metallic film of the first substrate, of the metallic film of the second substrate and of a layer of electrically conductive thermal adhesive interposed between the metallic films of the first and of the second substrate.

The two substrates are thus bonded back to back via their metallic films. This operation can take place after coating the free face of the metal layer of at least one of the substrates with a thin layer of thermal adhesive then by passing the two substrates between two heated pressing rollers.

The thermal adhesive layer is preferably an electrically conductive layer so as to ensure an electrical connection between the two metal layers. This electrical connection subsequently provides series or parallel interconnection of accumulators including the two adjoining substrates respectively.

It should be specified that a single metallic film can be used for the first substrate and the second substrate. In this case, the single metallic film is bonded respectively to one side of the main polymer films opposite to the side on which the retention reliefs project. The term "bonded" is understood as not excluding the possible possibility of coextrusion or coating of the metallic film directly on the main polymer film of one of the substrates.

Other characteristics and advantages of the invention emerge from the description which follows, with reference to the figures of the drawings. This description is given for purely illustrative and non-limiting purposes.

Brief description of figures

FIG. 1A is a schematic cross-section of a substrate illustrating a step for forming retention reliefs for the manufacture of a component according to the invention.

Figure 1B is a perspective view of a component blank similar to Figure 1A.

FIG. 1C is a schematic section of another substrate illustrating the formation of retention reliefs for the manufacture of a component according to the invention.

FIG. 2A is a schematic section of the substrate illustrating the formation of an electrically conductive layer forming a current collector.

FIG. 2B is a schematic section of a substrate illustrating an alternative embodiment.

FIG. 3A is a schematic section of the substrate of FIG. 2A and illustrates an operation for regularizing the height of the retention reliefs.

Figure 3B is a schematic representation of a rolling mill implemented for a continuous regularization operation (roll to roll - from roll to roll) of the height of the retention reliefs.

FIGS. 4 and 5 are schematic sections of the substrate illustrating steps for coating the substrate with a layer of active material.

Figures 6 and 7 are schematic cross-sections of a component according to the invention obtained by applying a separator film to the substrate of Figure 5.

Figure 8 is a schematic section of a component according to the invention illustrating a variant embodiment.

Figures 9 and 10 are schematic sections of a component according to the invention and illustrate another variant embodiment.

Figure 11 is a schematic section illustrating another possible embodiment of a substrate according to the invention.

Figure 12 is a schematic representation of an installation that can be used for the continuous manufacture of a substrate according to Figure 11.

Figure 13 is a schematic section of part of a component according to the invention and using the substrate according to Figure 11.

Figure 14 is a schematic section of an electric accumulator comprising an electric accumulator cell formed from components comparable to those of Figures 9 and 10.

FIG. 15 is a diagrammatic cross-section of components in accordance with the invention and illustrates a step for assembling an electric accumulator.

Figure 16 is a schematic section of components according to the invention and illustrates a step of assembling another electric accumulator.

Figure 17 is a schematic section of part of an electrical energy accumulator made from components according to the invention.

The figures are executed in free scale. For reasons of clarity, the different parts of the figures are not represented according to a uniform scale. In particular, the thickness of certain layers or thin films is exaggerated to improve the readability of the figures.

Detailed description of embodiments of the invention

In the following description, identical, similar or equivalent parts of the different figures are marked with reference signs of the same numerical value so as to facilitate transfer from one figure to another.

FIG. 1A shows a substrate 10 comprising a film 9 made of a polymer material on which are formed a certain number of heat-sealed retention reliefs 24 independent of each other. The retention reliefs 24 are distributed over the surface of the film 9. This is, for example, a heat-sealable polymer film that is electrically insulating and impermeable to an electrolyte. The example of FIG. 1A does not prejudge the use of other types of substrates and in particular of multilayer substrates or of substrates having other physical characteristics. Film 9 of substrate 10 is a thin film, with a thickness comprised, for example between 20 and 120 micrometers. It is considered here essentially in its support function.

The substrate comprises on one of its main faces 22 retention reliefs 24 made of thermal adhesive, in the form of small spikes or spikes. The tips are preferably hot formed when the thermoglue is liquefied. The retention reliefs can be deposited on the main face by a hot printer. They are distributed on the surface with regular or irregular spacing. The number of independent reliefs per surface unit is preferably between 50 and 250 units per square decimetre. The height of the retention reliefs is for example between 0.2 and 0.8 mm.

The number of retention reliefs per unit area can be adapted according to the size and shape of an electrical energy accumulator for which the component including the substrate is intended. In general, for large surface components the relative spacing of the retention reliefs between them can be greater than for small surface components. The spacing between reliefs can be different depending on the width and length of the substrate. It can be regular or not. Knowing that the retention reliefs also participate in the mechanical strength of the substrate, and therefore of the component including the substrate, their average spacing and the number of reliefs per unit area can also be adapted to the mechanical constraints of manufacturing an accumulator. 'electric energy.

In addition to the independent retention reliefs 24 indicated above, the substrate 10 bears, as also shown in FIG. 1B, on its main face 22 a lateral retention relief 26, also made of thermal adhesive. This relief surrounds a region of the substrate provided with retention reliefs 24. More specifically, the lateral retention relief forms, on the surface of the substrate 10, the side wall of a bowl 18 inside which there is a large number of retention reliefs 24 in the form of studs or tapered studs. The retention reliefs 24 can also have an elongated linear shape on the substrate (not shown in this shape in the figures), they are independent of each other.

The lateral retention relief is treated in the same way as the retention reliefs, whether they are tapered or linear. Also, and unless otherwise specified, the lateral retention relief and the retention reliefs of linear or frustoconical shape are indifferently referred to as “retention reliefs”.

The formation of the retention reliefs 24, 26 can be done by supplying material, and in particular by supplying thermoglue as shown in FIG. 1A. It can be preceded by a surface treatment of the substrate to clean the substrate and prepare it for receiving the retention reliefs, so as to improve their adhesion. The surface treatment can be treatment by plasma, by corona discharge, and/or by chemical means.

According to another possibility, illustrated by FIG. 1C, the retention reliefs 24, 26 can also be formed in one piece with the substrate 10. In the example of FIG. 1C, retention reliefs 24 are formed on the two opposite main faces of the substrate 10, by roll stamping a main polymer film 111 of the substrate 10. This is, for example, a heat-sealable polymer film that is electrically insulating and impermeable to an electrolyte. The retention reliefs 24 can also be formed when the polymer film 111 is extruded or by thermoforming this same film.

It can also be noted in FIG. 1C that the retention reliefs 24, 26 may comprise on their top parts, or covering their top parts, a layer of heat-sealing material 25. This is, for example, a heat-sealing adhesive comparable to that used for the formation of the retention reliefs 24 of FIG. 1A. The superficial layer of heat-bondable material is intended for fixing on the top parts of the retention reliefs of a polymer film, for example an electrically insulating separator film but permeable to the passage of ions. According to another possibility, the layer of heat-sealing material, also referred to as "heat-melting layer", may not be applied to all the retention reliefs 24, but nevertheless applied continuously and uniformly to the lateral retention relief 26. Thus , the bowl 18, surrounded by the lateral retention relief 26, is closed during the bonding of a polymer film on the lateral retention relief 26. The thickness of the thermal adhesive layer 25 can be from 3 to 10 micrometers for example. The placement of layers 25 of thermal glue limited to the top of the retention reliefs is a solution adopted in particular, when the main polymer film 111 of the substrate 10 is electrically conductive and is intended to also form a current collector in a storage battery. electric energy. This measure then makes it possible to prevent the heat-sealing layer from electrically insulating the substrate from the electrodes that it is likely to carry.

The fixing of a separator film on the top parts of the retention reliefs by means of thermoglue is described later in relation to Figure 6.

The substrates of FIGS. 1A, 1B and 1C can be used for continuing the process for manufacturing a component according to the invention.

A following operation is illustrated by FIG. 2A, starting from the substrate of FIG. 1A. It consists in forming on the substrate 10 an electrically conductive layer 30. This is, for example, a metallic layer of copper or aluminum formed by vacuum deposition, for example by magnetron sputtering, on the main face. 22 of the substrate 10. The electrically conductive layer 30, thin, for example a few tens to a few hundreds of nanometers, is intended to form a current collector of the substrate. It can be formed over the whole of the main face 22 of the substrate without necessarily being a continuous layer. Indeed, it can simply form an electrically conductive mesh on the main face 22 of the substrate so as to conduct the electrons which would be exchanged with a layer deposited subsequently, and in particular an electron-emitting or receiving layer.

According to a variant represented in FIG. 2B, the electrically conductive layer 30 can also be formed before the retention reliefs. In this case, the retention reliefs 24, 26 are formed on the electrically conductive layer 30.

It should be specified that the electrically conductive layer 30 can be formed on the whole of the main face 22 of the substrate 10. It can also be limited to parts of the substrate corresponding to the cups 18, or take the form of a electrical mesh on the main side of the substrate.

The following component manufacturing operations can be implemented from the substrate of FIG. 2A or from the substrate of FIG. 2B. For simplicity, the following operations are described starting from the substrate of FIG. 2A.

It may be noted that the various retention reliefs 24, 26 do not necessarily have a uniform height when they are deposited on the substrate.

Thus, before being supplied for the production of a component according to the invention, the substrate of FIG. 2A can advantageously be subjected to an operation of regularization, or of calibration of the height of the retention reliefs. During this operation the height of the reliefs is standardized.

The regularization of the height of the retention reliefs is illustrated by FIG. 3A. It consists in subjecting the substrate to a rolling mill 100 represented symbolically in the form of a pair of rollers 102, 104 conjugate of which at least one is heated, preferably the roller 102, in contact with the retention reliefs.

The passage of the substrate 10 in the rolling mill has the effect not only of standardizing the height of the reliefs 24, 26, but also of removing part of the electrically conductive layer 30 when the latter is at the top of the reliefs, as in the case of the substrate of FIG. 2A. The elimination of the electrically conductive layer 30 at the top of the reliefs can prove to be advantageous insofar as it prevents a certain quantity of conductive material from the conductive layer 30 from being introduced into an electrically insulating separator film in front of be transferred later to the substrate. Thus, the conductive layer 30 is preferably formed before the operation of standardizing the height of reliefs.

FIG. 3B illustrates the operation for standardizing the height of the retention reliefs by continuous passage (roll to roll) of the substrate 10 in the rolling mill 200. A first roller 210 unwinder is arranged upstream of the rolling mill 200. The substrate 10 coming from the unwinding roller 210 passes between the rollers 202, 204 of the rolling mill 200, at least one of which is heated, maintained at a calibrated distance from each other. Finally the substrate is received and rolled up on a winding roll 212 downstream of the rolling mill. For reasons of clarity, the retention reliefs located on the substrate 10 are not represented in FIG. 3B. The arrows present in the vicinity of the rollers 210, 212 indicate the direction of unwinding/winding up of the substrate.

The standardization of the height of the reliefs can also take place in a heated press whose height is calibrated.

The precision of the standardization of the height of the reliefs can be of the order of +/-5µm.

When the retention reliefs are produced by stamping or by thermoforming the substrate, as indicated with reference to FIG. 1B, their height is initially uniform. An additional height calibration operation is then not necessary.

A following operation of the manufacturing process comprises the coating of the substrate with a layer of active material. This operation is illustrated in Figures 4 and 5.

A first step of the packing, shown in FIG. 4, consists in depositing on the main face 22 of the substrate, and in particular in the bowl 18, a layer 40 of active electrode material and in leveling it at the height of the reliefs of retention 24.26 of bowl 18.

The active material is a material formed from particles and/or short fibres. The dimension of the particles or fibers is micrometric and/or nanometric. The composition of the active material depends on the type of electrode that it must form on the surface of the substrate and on the technology of the battery for which the component is intended. Simply by way of example, an active material intended to form a negative electrode for an energy accumulator of the lithium ion type can comprise particles of graphite, carbon and silicon or lithium metal.

To facilitate the deposition of the layer of active material 40, the particles of active material are mixed with a solvent constituting a liquid vector, so as to form a semi-liquid ink. The liquid carrier is, for example, dimethyl sulfoxide (DMSO), methyl-2-pyrrolidone (NMP), N-Butyl pyrrolidone (NBP), isopropanol or ethanol.

The leveling can be carried out by means of a blade 42 or a rotating brush. The blade 42 can bear, or at least a height reference, on the retention reliefs 24, 26. At the end of the leveling, the surface of the layer 40 of active material is flush with the top of the retention reliefs 24, 26. The thickness of the layer corresponds to the height of the retention reliefs.

A following step, illustrated by FIG. 5, comprises the evaporation of the solvent 44 used as liquid carrier. Evaporation is caused by heating the substrate under a fume hood.

The evaporation of the liquid vector has the consequence of reducing the thickness of the layer of active material 40 remaining on the substrate 10. The reduction in height can reach 30 to 50 percent of the initial height depending on the mass rate of liquid vector in the ink. The free ends of the retention reliefs 24, 26 now protrude from the surface of the layer of active material 40.

A following operation, considered as sealing, comprises the attachment to the substrate 10 of a separating film 50. The separating film is transferred onto the main face 22 of the substrate so as to cover the layer 40 of active material.

In the exemplary embodiment illustrated by FIG. 6, the separating film is welded to the substrate by thermal bonding. More specifically, a heating press, not shown, makes it possible to apply the separating film 50 to the layer 40 of active material and to partially melt the retention reliefs 24, 26 made of thermal adhesive. The separator film 50 is thus stuck on the retention reliefs 24, 26 and more precisely on the part of these reliefs which protrudes from the surface of the layer 40 of active material. The separating film 50 thus covers the whole of the bowl 18.

The separator film is, for example, a polymer film. It is electrically insulating and porous. The porosity of the separator film corresponds to its function of allowing ions carried by an electrolyte to diffuse into an energy accumulator. Its electrically insulating character makes it possible to avoid bringing the electrode formed by the layer of active material into electrical contact with an electrode of another homologous component of opposite polarity.

After the separator film has been bonded, the active material 40 is trapped in small cells, communicating with each other. The cells are delimited by the retention reliefs 24, 26 on the side edges of the component, the substrate 10 and the separator film 50.

Following the placement of the separator, and possibly concomitantly with its bonding, a compacting operation is carried out by means of a pneumatic or hydraulic press. The compacting makes it possible to reduce the thickness of the layer 40 of active material. The compacting operation is illustrated in Figure 7 where an arrow 52 in dashed lines symbolically indicates the action of a heating press or the action of the rollers of a rolling mill. The heating character of the press or of at least one roll of the rolling mill makes it possible to soften the retention reliefs adhering to the separator. When they cool, the retention reliefs firm up again and maintain the active material at the residual thickness reached after compaction.

The components 1 according to FIGS. 6 and 7 are capable of being implemented for the production of an electrical energy accumulator cell. Such a cell is described below.

FIG. 8 shows another possible embodiment of a component according to the invention.

Substrate 10 (10a, 10c) of component 1 of FIG. 8 has two opposite main faces 22a and 22c. It comprises two support polymer films 9a, 9c joined to one another by a face devoid of retention reliefs. The films can be joined by means of a layer of electrically conductive thermoglue, not shown, or can be replaced by a single support film.

Each of the main faces 22a, 22c receives retention reliefs 24a, 24c, 26a, 26c, an electrically conductive layer 30a, 30c, a layer of active material 40+, 40- forming an electrode, and a separating film 50a, 50c. The active material 40+, 40- of the electrodes, held by the retention reliefs 24a, 24c, is respectively contained in basins 18a, 18c, delimited respectively by linear retention reliefs 26a, 26c, and covered with the separating film 50a, 50c. The manufacture of the retention reliefs 24a, 24c, 26a, 26c, the deposition of the active material 40+, 40-, and the fixing of the separator films 50a, 50c can take place according to the methods already described with reference to FIGS. 1 to 6.

Component 1 of FIG. 8 can advantageously constitute a bipolar component with an active electrode material 40+ on one of its main faces 22a and an active negative electrode material 40- on the opposite main face 22c.

Figures 9 and 10 illustrate yet another possible embodiment of a component according to the invention.

In FIG. 9, component 1c comprises a composite substrate 10c formed from a stack of three layers.

It comprises an electrically insulating outer layer 11c, a central electrically conductive layer 12c, and an electrically insulating inner layer 13c. It should be specified that the outer 11c and inner 13c layers can also be electrically conductive. The terms "external" and "internal" are understood herein as "facing away from the electrode" and "facing towards the electrode", respectively.

The outer layer 11c can be, for example, a layer of polyethylene terephthalate (PET) or of polypropylene (PP) with a thickness of 20 to 100 μm, preferably 30 μm. The internal layer 13c of the substrate is, for example, a layer of polypropylene, also with a thickness of 20 to 100 μm, preferably 30 μm. Polymer materials may or may not be charged with conductive particles. The central electrically conductive layer 12c is, for example, an aluminum layer with a thickness of 80 to 100 μm, preferably 40 μm.

The composite substrate 10c on the side of its internal layer 13c bristles with retention reliefs 24c, 26c and is lined with a layer of active material 40+ forming a positive electrode (cathode). This is, for example, LiNiMnCoO₂or LiNiCoAlO₂ for a component 1c intended for a lithium accumulator. The layer of active material 40+ is received on a first electrically conductive layer 30c, made of aluminium. The layer of active material is covered with a separating film 50c. The first electrically conductive layer has a thickness of 80 to 150 nm. It covers the internal layer 13c of the substrate 10c. It is formed before the retention reliefs 24c, 26c, so that it does not cover the retention reliefs 24c, 26c. The electrically conductive layer 30c forms a current collector.

The free face of outer layer 11c is also covered with a second electrically conductive layer 31c. It is also a layer of aluminum or stainless steel with a thickness of 80 to 150 nm.

The first electrically conductive layer 30c and the second electrically conductive layer 31c are respectively in electrical contact with the central electrically conductive layer 12c and therefore in electrical contact with each other. It can be noted, in fact, that contact wells 16c and 17c are respectively formed in the outer layer 11c and the inner layer 13c of the substrate 10c. The contact wells 16c, 17c are holes or grooves crossing right through the inner layer, respectively the outer layer of the substrate. The first and second electrically conductive layers 30c, 31c extend into the contact wells 16c, 17c so that they are in electrical contact with the central electrically conductive layer 12c.

As all of the electrically conductive layers 30c, 31c and 12c are in electrical contact with each other and with the active material electrode, they form a current collector. However, the functions of the three layers are different. The first electrically conductive layer 30c, made of aluminium, provides physical and electrical contact with the electrode, that is to say with the layer of active material 40+. The second conductive layer 31c, ensures a possible physical and electrical connection contact of the component 1c with other external components. It can constitute a connection terminal of an electric accumulator using the component.

The central conductive layer 12c, assembled by lamination with the internal and external layers 13c, 11c of the substrate 10c, in addition to its function of electrical contact can also have a function consisting in improving the tightness of the substrate. The tightness of the substrate is understood with respect to an electrolyte when the substrate is used in an energy accumulator cell.

Figure 10 shows part of a component 1a similar to that of Figure 9 shown by reversing the order of the layers. The references of the various parts of the component are the same as those of FIG. 9 followed by the letter "a" instead of the letter "c". Reference may thus be made to the preceding description.

Unlike Figure 9 which shows a component carrying a positive electrode, Figure 10 shows a component carrying a negative electrode. The negative electrode is formed of a layer of active material 40-. It is, for example, a layer comprising particles of graphite, carbon and/or silicon. Also, the first electrically conductive layer 30a is a layer of copper in component 1a whereas it is an aluminum layer in component 1c of FIG. 9 essentially for reasons of electrochemical compatibility.

Figures 8 to 10, which have just been described, illustrate the production of a component according to the invention from a substrate comprising hot-melt retention reliefs added to the substrate.

Yet another possible embodiment of a substrate 10 is described below, with reference to Figures 11 and 12.

Figure 11 shows part of a main electrically conductive polymer film 111 which has undergone deformation by thermoforming giving it a shape with reliefs. This is, for example, an electrically conductive polymer film (for example polypropylene or charged polyethylene) with a thickness of 20 to 300 μm.

The reliefs of the polymer film constitute retention reliefs 124, 126 comparable to those of the figures previously described. The retention reliefs include tapered reliefs 124 and a lateral retention relief 126.

The retention reliefs 124, 126 form projections on a first face 113 of the main polymer film 111. This is the face intended to subsequently receive the active material for the production of a component according to the invention.

On a second face 115, opposite the first face 113, it can be seen that the main polymer film 111 comprises depressions. This is the hollow relief corresponding to the retention reliefs.

As shown in FIG. 11, the production of a substrate 10 is completed by bonding the main polymer film to a metallic film 112. This is, for example, an aluminum film, a film in one aluminum based alloy or stainless steel film. More generally, the metal is chosen for its electrical conductivity and mechanical strength properties. Its thickness can be around 20 to 80 µm.

The metallic film 112 is glued against the second face 115 of the main polymer film 111. It can be noted that the metallic film is flat and does not follow the shape of the depressions of the second face 115 of the main polymer film. Thus, and more specifically, the bonding takes place outside the zones of the main polymer film corresponding to the retention reliefs 124, 126.

The bonding of the film takes place by means of a layer of electrically conductive thermal adhesive 117 which covers one side of the metallic film 112 coming against the main polymer film. The electrically conductive heat seal layer 117 can be omitted in the case of direct coating of the main polymer film 111 on the metal film 112. For simplicity, the heat seal layer 117 is not shown in the following figures.

The formation of the substrate 10 by thermoforming a main polymer film and by bonding or coating on a metal film is an operation which can take place continuously (roll to roll) as shown in figure 12.

Figure 12 shows an installation 300 for the continuous formation of a substrate according to Figure 11. The installation 300 comprises a first unwind roll 310 and a second unwind roll 312, a forming unit 320 and a coating unit 330 Forming unit 320 receives main polymer film 111 from unwind roll 310. Main polymer film 111 passes between heated rolls 322, 324 of the forming unit. The heating rollers 322, 324 respectively present conjugate complementary reliefs 326, 328, corresponding to the retention reliefs to be formed on the main polymer film.

The coating unit 330 receives the main polymer film 111 at the exit of the forming unit 320 and the metallic film 112 coming from the second unwind roll 312. The coating unit 330 also comprises two conjugate heating rolls 324, 332 between which pass the main polymer film and the metallic film. It may be noted that the forming unit 320 and the coating unit 330 share a common heating roller 324. The mating heating rollers 324, 332 of the coating unit have the function of applying the metallic film 112 to the of the main polymer film not having the retention reliefs and to stick the metallic film on this face. The heating roller 324 placed on the side of the main polymer film has, as previously indicated, a relief 326, corresponding to the pattern of the retention reliefs, while the heating roller 332 receiving the metal film is smooth. The metal film 112 may have on its face facing the main polymer film a layer of conductive thermoglue promoting its bonding. It is not shown in Figure 12.

Once the film 111 has been formed and associated with the metal film 112 to form the substrate 10, the latter is wound on a take-up roll 314.

The combination of the metallic film 112 and the main polymer film 111 constitutes a substrate 10 which can be used for the production of a component 1 according to the invention. In this case, the substrate can be lined with a layer of active electrode material particles 40, without binder, and covered with a separator film 50 as shown in Figure 13.

The coating of the substrate with the active electrode material, and the attachment to the substrate of a separator film can take place in the manner described with reference to Figures 4 to 6.

Note, however, that to bond the separator film 50 to the substrate 10, and more specifically to the retention reliefs 124, 126 of the substrate, a thin layer of thermoglue 125 is placed at the top of the retention reliefs. The thin layer of thermal glue is also visible in FIG. 11. It can be formed by hot coating and is preferably electrically insulating so as not to disturb the insulating nature of the separator. It is preferably formed after the packing of the substrate with the active material and after evaporation of the solvents. When gluing the separator film, the heat-sealing layer diffuses locally into the separator film at the location of the retention reliefs.

Figure 14 shows an electric accumulator cell 100 formed by assembling two components 1a and 1c as described with reference to Figures 9 and 10.

The components are superposed by bringing their separating films 50a, 50c into mutual contact.

It can be noted in FIG. 14 that the first electrically conductive layer 30a, 30c, the second electrically conductive layer 31a, 31c, the intermediate conductive layer 12a, 12c, the retention reliefs 24a, 24c, 26a, 26c and the layers of material active 40+, 40- of the components 1a, 1c do not extend over the entire surface of the substrates 10a, 10c of the components. In fact, only the internal 13a, 13c and external 11a, 11c layers of the substrates 10a, 10c, that is to say the electrically insulating polymer layers extend in a peripheral zone 102 of the substrates. These layers are also devoid of openings or connection wells 16a, 16c, 17a, 17c in the peripheral zone 102.

The peripheral zone 102 can have a width of a few millimeters to one centimeter. When the polymer layers of the substrate are heat-weldable, a peripheral sealing joint 104 can be formed by applying a heating frame in the peripheral zone 102, so as to weld the polymer layers together. The joint thus makes it possible to seal the cell 100 formed of the two components and ensures its peripheral tightness. According to another possibility, a sealing joint, for example an electrically insulating polymer joint, can also be attached between the two components and bonded to the layers extending in the peripheral zone. The sealing joint is limited to the peripheral zone.
An electrolyte can then be introduced into the cell. When it is filled with an electrolyte 106, the cell 100 forms an accumulator of electrical energy.

A battery formed from several individual electric accumulators can be formed by a stack of cells as represented in FIG. 14. More generally, a battery can be formed by association in series and/or in parallel of a plurality of individual cells or by the placing in series, respectively in parallel, of sub-assemblies comprising in turn individual cells in parallel, respectively in series.

According to another possibility, also described later in relation to FIG. 16, one or more components 1b such as component 1 according to FIG. 8 can be interposed between components 1a and 1c of FIG. 15, respecting an alternation of positive and negative electrodes.

FIG. 15 illustrates an operation for assembling components according to the invention for forming an energy accumulator during which one of the components is completed during assembly. For simplicity, the peripheral zone of the components mentioned in connection with FIG. 15 is not shown.

A first component 1a, comparable to that of FIG. 7, comprises a negative electrode 40- in contact with an electrically conductive layer 30a forming a current collector. The references indicated in Figure 15 are those of Figure 7 followed by the letter "a". It is thus possible to refer to FIGS. 7 and above.

A second component 1c is brought close to component 1a. The part numbers are the same for both components except that the letter c follows the part numbers for component 1c. The second component is provided with a positive electrode 40+ in contact with an electrically conductive layer 30c forming a current collector.

It can be observed that the second component 1c, unlike component 1a, has no separating film. The component is thus comparable to the component blank in Figure 5.

The second component 1c is transferred onto the first component 1a by bringing its positive electrode 40+ into contact with the separating film 50a of the first component 1a. The two components are then subjected to a heating press making it possible to heat-bond the second component 1c on the separating film 50a of the first component. Heat bonding is used by taking advantage of the retention reliefs 24c of the second component 1c which, by partially melting, are fixed on the separator 50a.

A compaction of the two components is also carried out. Preferably the assembly of the two components is carried out by transferring the component supporting or requiring the strongest compaction onto the component supporting or requiring more limited compaction. Indeed, the layer of particles of active material of the component initially provided with the separator film undergoes two hot pressing operations while the layer of particles of active material of the component initially devoid of separator film only undergoes a single heating press operation.

The ends of components 1a and 1c are then sealed, for example in the manner indicated with reference to Figure 14 to form an accumulator cell.

In FIG. 15, for reasons of clarity, the height of the retention reliefs 24 and 26 for the two components is substantially identical, and the thickness of the layers of particles of active material forming the positive and negative electrodes 40+ and 40- is also substantially identical. It should be noted, however, that this is neither a necessary measure nor a general rule. Indeed, and on the contrary, the thicknesses of the layers of active material forming the positive and negative electrodes, and therefore the height of the retention reliefs, can be adjusted independently for each component or for each side of the same bipolar component. It is thus possible to independently adjust the ion storage capacity of the positive electrode and of the negative electrode which is conjugated to it, so that these capacities are those retained during the dimensioning of the energy accumulator.

For this purpose, it is possible, for example, to initially set the height of the retention reliefs and the thickness of the positive electrode (cathode side) and then determine the height of the retention reliefs and the thickness of the negative electrode, depending on the materials used, to adapt the ion storage capacity.

FIG. 16 illustrates the formation of an energy accumulator by assembling three components 1a, 1b, 1c. As for Figure 15, the peripheral part of the components is not represented.

A first component 1a is comparable to the first component 1a of FIG. 15. It comprises a negative electrode 40- and a separating film 50a. A second component 1c is comparable to the second component 1c of FIG. 15. It comprises a positive electrode 40+ and has no separating film. Finally, a third component, 1b, placed between the first component 1a and the second component 1c is a bipolar component comparable to that of FIG. 8.

The third component, 1b, comprises a face with a positive electrode 40+, devoid of a separator, and an opposite face with a negative electrode 40- and provided with a separator film 50b.

For simplicity, the conductive layers forming current collectors of the three components are indicated indistinctly with the reference numeral 30. These are continuous conductive layers extending over the retention reliefs 24, 26. The arrangement of the components is such that a separating film 50a, 50b is respectively arranged between two electrodes of opposite polarity of two successive components.

The assembly, signified by hatched arrows, is carried out under a heating press so that the retention reliefs, and in particular the retention reliefs located on the faces of the components initially devoid of separator film, stick to the separator film. of the opposite component. In the example shown, during assembly the retention reliefs 24, 26 are aligned.

After assembly, a border (not shown) of a battery thus formed of two cells in series, can be sealed in the manner already mentioned in connection with FIG. 14. The cells can be lined, independently of one of them. another, an electrolyte to form electrical energy accumulators, interconnected in series in the battery. The electrolyte can be in the form of a liquid, a gel or a polymer. It should be specified that the electrolyte cannot circulate from one cell to another, each cell being sealed in relation to the other cell.

According to a comparable pattern, it is also possible to produce accumulator batteries comprising a number of cells greater than two.

The conductive layers 30 forming the current collector of the components 1a and 1c constitute external terminals of the electrical energy accumulator. Furthermore, the conductive layers 30 forming the current collector on the two opposite faces of the central bipolar component 1b are interconnected by the supporting polymer films 9b which are electrically conductive here.

Figure 17 shows part of a stack of components 1a, 1b, 1c, 1d that can be implemented in an electrical energy accumulator and using components comparable to that of Figure 13 or components made from a substrate comparable to that of FIG. 1C.

Components 1a, 1b, 1c, 1d each have a main polymer film 111a, 111b, 111c, 111d, respectively. The main polymer film has undergone thermoforming to form retention reliefs 124. The main polymer film used for each component is a charged and electrically conductive polymer film, so that each main polymer film also constitutes a current collector. The main polymer film is also electrolyte tight.

By analogy with the preceding figures, the layers of electrode active material particles are marked with the numerical references 40+ (for a positive electrode) and 40- (for a negative electrode). They are also referred to as "positive electrode" and "negative electrode".

For components 1a and 1d, the retention reliefs are only made on one of the faces of the main polymer film. The opposite face is coated on a metal film 112a, 112d which can either serve as the outer casing of the battery consisting of three electrical energy accumulators, or be brought into contact with other components of the stack, not shown. . Component 1a includes a negative electrode 40- while component 1d includes a positive electrode 40+.

Components 1b and 1c are made from a substrate comparable to that of FIG. 1C formed from a main electrically conductive polymer film having retention reliefs on its two opposite main faces. The main electrically conductive polymer film also forms the current collector. These are so-called “bipolar” components knowing that they carry 40+ and 40- electrodes of opposite signs on their opposite main faces. It may be noted that the particles of active material of the electrodes come to fill the recessed parts formed respectively by the retention reliefs on the face opposite to that on which they protrude.

In the stack, each positive 40+, respectively negative 40-, electrode of a component faces a negative 40-, respectively positive 40+ electrode of an adjacent component. The electrodes 40+, 40- of the adjacent components are separated by separator films 50ab, 50bc, 50cd glued to the top part of the retention reliefs 124. Thus, the separator films 50ab, 50bc, 50cd are placed between the components 1a and 1b , 1b and 1c, and 1c and 1d, respectively. The gluing of the separator films 50ab, 50bc, 50cd on the retention reliefs can take place by means of a thermoglue lining. This is a 125 heat seal gasket as shown in Figures 11 and 13.

An electrical energy battery comprising the stack of components of Figure 17, comprises several cells electrically connected in series via main polymer films 111a, 111b, 111c. The main polymer films 111a, 111b, 111c also prevent passage of the electrolyte (not shown) from one cell to another.

Claims (33)

1) Component (1, 1a, 1c) for an electric accumulator, comprising:
- a substrate (10, 10a, 10c) comprising at least one electrically conductive layer (30, 30a, 30c, 12a, 12c, 111, 112) forming a current collector,
- at least one separating film (50, 50a, 50c),
- at least one layer (40, 40+, 40-) of electrode active material particles, in electrical contact with the current collector layer, and placed between the substrate and the separator film, characterized in that:
- the layer of electrode active material particles is devoid of binder,
- at least one of the substrate and of the separator film is bristling with retention reliefs (24, 24a, 24c, 26, 124, 126) of the layer of particles of electrode active material, the reliefs being independent of each other others and extending between the substrate (10, 10a, 10c) and the separator film (50, 50a, 50c). 2) Component according to claim 1, comprising retention reliefs (24) formed in one piece with at least one of the substrate and the separator film. 3) Component according to claim 2, in which the substrate comprises a main polymer film (111, 111a, 111b, 111c, 111d) and in which the retention reliefs (124) are formed in one piece with the main polymer film . 4) Component according to claim 3, wherein the main polymer film is associated with a metal film (112, 112a, 112d). 5) Component according to claim 3 or 4, wherein the substrate (10) comprises at least one surface layer (25, 125) of heat-sealable or heat-adhesive material. 6) Component according to claim 1, comprising retention reliefs (24, 24a, 24b, 26) in a heat-sealable or heat-adhesive material, fixed to the substrate (10, 10a, 10c). 7) Component according to any one of the preceding claims, in which the retention reliefs (24, 24a, 24c, 26, 26a, 26c, 124, 126) comprise at least one of frustoconical reliefs (24, 24a, 24c , 124) and linear reliefs (26, 26a, 26c, 126). 8) Component according to claim 7, in which the frustoconical reliefs having at their base a diameter of between 0.2 and 1.2 mm, having at their top a diameter of between 0.1 mm and 0.4 mm, and a height of 0.2 to 0.8mm. 9) Component according to claim 7 or 8, wherein the retention reliefs are frustoconical reliefs having, between neighboring reliefs, an average spacing of between 5 and 20 mm. 10) Component according to any one of the preceding claims, in which:
- the substrate (10) has at least one depression (18, 18a, 18c) on at least one of its faces (22, 22a, 22c),
- the cuvette is covered by the separating film (50, 50a, 50c, 50ab, 50bc, 50cd),
- the retention reliefs and the layer (40, 40+, 40-) of particles of active material are located inside the bowl (18, 18a, 18c) between the substrate and the separator film. 11) Component according to any one of the preceding claims, in which:
- the substrate (10) has a first main face (22a) and a second main face (22c) opposite the first main face,
- the first and the second main face are provided with retention reliefs (24a, 24c, 26a, 26c),
- the first and the second main face carry respectively a layer (40+) of positive electrode active material particles and a layer (40-) of negative electrode active material particles,
- a separating film (50a, 50c) respectively covers the layer of active electrode material and the retention reliefs of the first and of the second main face. 12) Component according to any one of the preceding claims, in which the electrically conductive layer (30, 30a, 30c) forming a current collector covers one face (22, 22a, 22c) of the substrate receiving the retention reliefs (24, 24a , 24c, 26, 26a, 26c). 13) Component according to claim 12, wherein:
- the substrate (10a, 10c) is a film comprising a central conductive layer (12a, 12c) sandwiched between a first layer of polymer (13a, 13c) receiving the retention reliefs and a second layer of polymer (11a, 11c ),
- the electrically conductive layer (30a, 30c) forming a current collector covers one face of the first polymer layer (13a, 13c) receiving the retention reliefs (24a, 24c, 26a, 26c),
- the electrically conductive layer (30a, 30c) forming a current collector is electrically connected to the central electrically conductive layer, via connection wells (17a, 17c) passing through the first polymer layer (13a, 13c). 14) Component according to any one of claims 12 and 13, wherein:
- the substrate (10a, 10c) is a film comprising a central conductive layer (12a, 12c) sandwiched between a first layer of polymer (13a, 13c) receiving the retention reliefs and a second layer of polymer (11a, 11c ),
- the electrically conductive layer (30a, 30c) forming a current collector covers one face of the first polymer layer (13a, 13c) receiving the retention reliefs (24a, 24c, 26a, 26c),
- the first layer of polymer (13a, 13c) receiving the retention reliefs is electrically conductive,
- the electrically conductive layer (30a, 30c) forming a current collector is electrically connected to the central electrically conductive layer, via the first electrically conductive polymer layer (13a, 13c) receiving the retention reliefs. 15) Cell (100) of electrical energy accumulator comprising at least a first component (1c) according to any one of the preceding claims, provided with a layer (40+) of positive electrode active material particles, and at least a second component (1a) according to any one of the preceding claims provided with a layer (40-) of particles of negative electrode active material, the first component being superimposed on the second component and the separator film (50c ) of the first component being in contact with the separator film (50a) of the second component. 16) Cell (100) of electrical energy accumulator comprising at least a first component (1c) according to any one of claims 1 to 14, provided with a layer (40+) of particles of active electrode material positive, and at least one second component (1a) according to any one of Claims 1 to 14, provided with a layer (40-) of negative electrode active material particles, the first component being superimposed on the second component, and the layer of particles of active material (40+) of the first component (1c) being separated from the layer of particles of active material (40-) of the second component by a separator film (50a) common to the first and to the second component. 17) Cell according to any one of claims 15 and 16, wherein the substrate (10) of the first component (1c) and the substrate (100) of the second component (1a) respectively have a peripheral zone (102) devoid of particles electrode active material and electrically conductive layers, and wherein a seal (104) connects the substrate of the first component to the substrate of the second component in the peripheral zone, the substrate of the first component and the substrate of the second component forming , with the seal, a sealed enclosure of the cell. 18) Cell according to claim 17, in which:
- the substrate of the first component and the substrate of the second component each comprise at least one layer (11,13) of electrically insulating thermofusible polymer,
- the peripheral zone (102) has no conductive layer and active electrode material,
- the sealing joint (104) is a solder joint between the layer of thermofusible polymer (11, 13) of the substrate (10) of the first component (1c) and the layer of thermofusible polymer (11, 13) of the substrate (10 ) of the second component (1a). 19) Cell according to claim 17, wherein the seal (104) includes a heat seal. 20) Electrical energy accumulator comprising at least one cell (100) according to any one of claims 15 to 19, and an electrolyte (106) contained in the sealed enclosure of the cell. 21) A method of manufacturing a component according to any one of claims 1 to 11, comprising the following successive steps:
a) the supply of a substrate (10) comprising at least one face (22) provided with an electrically conductive layer (30) forming a current collector and provided with retention reliefs (24, 26, 124, 126),
b) the coating of said face with a layer (40) of particles of active electrode material,
c) the leveling off of the layer (40) of particles of active material at the level of the retention reliefs (24, 26, 124, 126),
d) fixing to the retention reliefs (24, 26, 124, 126), a separator film (50) covering the layer (40) of particles of active material. 22) Process according to claim 21, comprising before step b), an operation of standardizing the height of the retention reliefs. 23) Method according to any one of claims 21 and 22, wherein step b) of packing comprises the application, on the face (22) provided with retention reliefs (24, 26, 124, 126), of a mixture of particles of active electrode material (40) and a volatile carrier liquid (44), the method further comprising a step of evaporating the carrier liquid, after the leveling of the layer of particles. 24) A method according to any one of claims 21 to 23, wherein step a) comprises the formation on one side of the substrate of the retention reliefs (24, 26) in an elastic heat seal, and wherein, during the step d) the separator film (50) is heat-sealed onto the retention reliefs. 25) Method according to any one of claims 21 to 24, wherein step a) comprises depositing the layer (30), forming a current collector, on the face (22) of the substrate, provided with the retention reliefs (24), the layer forming the current collector covering the retention reliefs. 26) Process according to claims 22 and 25 wherein the standardization of the height of the reliefs is carried out after the deposition of the layer (30) forming a current collector. 27) The method of claim 25, wherein the current collector layer is formed by magnetron sputtering. 28) Process according to claim 21, for manufacturing a component according to any one of claims 1 to 11, provided with a main polymer film and a metallic film, in which step a) comprises:

• providing a primary electrically conductive polymer film (111), and
• the formation on the main polymer film of retention reliefs (124, 126), the retention reliefs protruding from a first face (113) of the main polymer film, the formation of the retention reliefs taking place by thermoforming of the main polymer film,
• bonding the main polymer film to a metal film (112), a second face (115) of the main polymer film (111), opposite the first face (113), being transferred against the metal film (112) during bonding.

29) The method of claim 28, wherein the metal film (112) is lined with a heat-sealing layer (117), electrically conductive, on one face receiving the second face (115) of the main polymer film during bonding, and wherein the bonding of the main polymer film (111) to the metallic film is hot heat bonding using the heat seal layer (117). 30) A method according to any one of claims 28 and 29 further comprising the formation of a thermal adhesive layer selectively lining a top of each retention relief on the first face (113) of the main polymer film. 31) Process according to claims 28 to 30, wherein at least one of the operations of thermoforming, gluing and forming a layer of thermal adhesive is carried out continuously. 32) Process according to any one of claims 28 to 31, in which
the main polymer film (111) is one of a polypropylene film and a polyethylene film, loaded with carbonaceous electrically conductive particles. 33) Method according to any one of claims 21 to 32, further comprising, during step d), or at the end of step d), compacting the layer (40) of particles of active ingredient.