Battery cell manufacturing process

Abstract

Method for manufacturing a battery cell. The invention relates to a method and a system (1000) for manufacturing a battery cell, said method comprising the following steps: - providing a separator film (103); - forming electrode assemblies such that each electrode assembly (3) comprises a first electrode (1), a second electrode (2), and a portion of the separator film (103), said portion being interposed between said first (1) and second (2) electrodes; - forming, in a stacking station (300), a stack of electrode assemblies (3). Figure 1

Description

Title of the invention: Method of manufacturing a battery cell Technical field of the invention

[0001] The invention relates to the technical field of manufacturing a battery cell. In particular, the invention relates to a method for manufacturing a battery cell and a system for manufacturing a battery cell. State of the art

[0002] It is known to manufacture a lithium-ion battery with a battery cell comprising a stack, said stack comprising positive electrodes and negative electrodes and in which the electrodes are separated two by two by a separator film interposed between two electrodes. To obtain such a stack, it is known to treat each layer of the stack one by one, said layer being chosen from: a positive electrode, a negative electrode, a separator film; this is not satisfactory because the manufacture of such a stack requires a lot of time.

[0003] To improve the manufacturing speed, it is known to use a separator film that is integrated into the stack by folding said separator film in an accordion fashion; thus, the same separator film is arranged to separate each pair of adjacent electrodes in the stack. For this purpose, at each fold of the separator film added to the stack, an electrode selected from a positive electrode and a negative electrode is added to a portion of the separator film previously added to the stack. However, in some cases, a problem arises: folding the separator may generate creases in said separator and cause mechanical damage to the battery cell. Furthermore, due to the increasing demand for battery cells, another problem to be solved is that of accelerating the manufacturing process of battery cells.

[0004] In an attempt to solve the above-mentioned problems, patent application US 2015 / 0263375 A1 describes a device with which, during the production of an electrode stack, a separator film is folded alternately on both sides of an electrode stack. This device uses supports, which are placed as close as possible to the fold to be formed, immobilize the material to be folded for separation over its entire width, and pocket formation occurs by means of a gas flow from an overpressure module over the entire width of the separator film, which allows for damage-free and smooth accordion folding.

[0005] However, the solution described in document US 2015 / 0263375 A1 is based on a guide device for accordion folding of the separator film, as well as at least one clamp for picking up and removing the electrodes and a pressure relief module, which suggests that the process is expensive to implement and that the movement of the different elements used slows down the manufacturing process of the battery cell. Subject of the invention

[0006] The object of the present invention is to provide a battery cell manufactured at a rapid rate.

[0007] To this end, the present invention relates to a method of manufacturing a battery cell, said method comprising the following steps: - provide a separating film; - forming electrode assemblies such that each electrode assembly comprises a first electrode, a second electrode and a portion of the separator film, said portion of the separator film being interposed between said first electrode and said second electrode; - forming, in a stacking station, a stack of electrode assemblies, the step of forming the stack comprising multiple folding of the separator film; each set of electrodes being formed before the introduction of said set of electrodes into the stacking station.

[0008] In particular, it can be understood that each set of electrodes comprises its own portion of the separator film, said own portion being different from the portion of the separator film included in each of the other sets of electrodes.

[0009] Advantageously, the method described allows high-speed stacking and less handling of the separator film, which results in faster stacking of the electrode assemblies and therefore in an acceleration of the manufacture of the battery cells.

[0010] Advantageously, the method described makes it possible to obtain a satisfactory alignment of the electrodes within the set of electrodes because the set of electrodes is formed before introducing the set of electrodes into the stack of sets of electrodes, which makes it possible to improve the overall alignment of the electrodes within the battery cell.

[0011] For each set of electrodes, the first electrode and the second electrode may be selected from a cathode and an anode. Thus, in this case, each set of electrodes comprises an anode and a cathode. For example, the first electrode is an anode for a battery cell and the second electrode is a cathode for the battery cell.

[0012] The method may further comprise one or more of the following features.

[0013] According to one characteristic, the method is such that the first electrodes of the battery cell to be manufactured are positioned sequentially on the separator film, each first electrode positioned on the separator film being intended to be associated with one of the second electrodes of the battery cell to be manufactured during the step of forming the sets of electrodes, said method comprises, for each pair of consecutive first electrodes positioned on the separator film, a distance verification step in order to determine whether or not the distance between the two consecutive first electrodes of said pair has a predefined value.

[0014] According to one feature, the method may comprise a step of cutting the separator film after completion of the stacking of electrode assemblies, to enable the battery cell comprising the stacked electrode assembly to be obtained from the stacking station.

[0015] Advantageously, cutting the separator film after completion of the stacking of electrode assemblies facilitates obtaining the battery cell from the stacking station.

[0016] According to one feature, the step of forming the stack may be such that each pair of adjacent electrode sets in the stack of electrode sets comprises two electrode sets respectively called first electrode set and second electrode set, the first electrode set and the second electrode set being stacked with the interposition of a part of a connecting portion, said connecting portion being formed by a corresponding part of the separator film and connecting the portion of the separator film of said first electrode set to the portion of the separator film of said second electrode set.

[0017] Advantageously, the interposition of the part of the connecting portion between the first set of electrodes and the second set of electrodes makes it possible to isolate each adjacent set of electrodes in the stack as well as the first and second electrodes of each set of electrodes using the same separator film.

[0018] According to one feature, for each set of electrodes introduced into the stacking station after a set of electrodes previously introduced into the stacking station, the step of forming the stack of sets of electrodes may comprise a first folding of the separator film in a first folding direction and a second folding of the separator film in a second folding direction to allow the stacking of said set of electrodes introduced with the corresponding set of electrodes previously introduced, the first and second folding directions being opposite.

[0019] Advantageously, the first and second folding of the separator film in opposite directions makes it possible to isolate sets of electrodes within the stack and to limit the dimension of a corresponding part of the separator film between two stacked sets of electrodes.

[0020] According to one characteristic, for each set of electrodes introduced into the stacking station after a set of electrodes previously introduced into the station stacking, the step of forming the stack of electrode sets comprises moving said previously introduced electrode set to enable stacking of said introduced electrode set with said previously introduced electrode set.

[0021] Advantageously, the movement of said previously introduced set of electrodes makes it possible to avoid creases in the separator film.

[0022] According to one feature, the stacking station comprises a stacking platform configured to perform a linear movement in a direction substantially parallel to a stacking direction of the electrode assemblies in the assembly station and configured to support the electrode assembly, and in which each movement is performed by the linear movement of the stacking platform, the speed of the linear movement of the stacking platform being adapted to the running speed of the separator film.

[0023] Advantageously, such a linear movement of the stacking platform makes it possible to impose the movement of said previous set of electrodes to allow the stacking of the set of electrodes newly introduced into the stacking station.

[0024] According to one characteristic, the step of forming the sets of electrodes comprises a step of checking the assembly such that, for each set of electrodes, an alignment between the first electrode and the second electrode of said set of electrodes is checked so as to verify whether or not one of said first and second electrodes completely covers the other of said first and second electrodes.

[0025] Advantageously, the assembly control step makes it possible to check the alignment of the electrodes in order to maximize the capacity of the battery cell.

[0026] According to one characteristic, the step of forming the stack of sets of electrodes may comprise a step of controlling the stack such that, for each set of electrodes introduced into the stacking station, the alignment between the first electrode and the second electrode is controlled so as to verify whether or not one of said first and second electrodes completely covers the other of said first and second electrodes after one of said first or second electrodes has been held and transported by an electrode-holder device towards the stacking station.

[0027] Advantageously, the stacking control step makes it possible to determine whether or not the second electrode has slipped from its position and has therefore broken the alignment between the first and second electrodes.

[0028] According to one characteristic, the step of forming sets of electrodes may comprise, for each set of electrodes to be formed, a step of rolling the first electrode of said set of electrodes onto the separator film, so that said first electrode is integral with the separator film at the end of said step of rolling.

[0029] Advantageously, the rolling of the first electrode makes it possible to fix the first electrode on the separator film in order to manufacture the set of electrodes.

[0030] According to one feature, after completion of the stacking of electrode assemblies, the separator film is cut to enable the battery cell comprising the stacked electrode assembly to be obtained from the stacking station.

[0031] Advantageously, cutting the separator film makes it possible to obtain the battery cell.

[0032] The invention also relates to a system for manufacturing a battery cell, said system comprising: - a separator film supply station; - an electrode assembly station configured to form electrode assemblies such that each electrode assembly comprises a first electrode, a second electrode and a portion of the separator film, said portion of the separator film being interposed between said first electrode and said second electrode; and - a stacking station in which a stack of electrode assemblies is intended to be formed by multiple folding of the separator film; said system being configured to allow the separator film to travel from the supply station to the stacking station, the electrode assembly station being arranged so as to be crossed by the separator film between the separator film supply station and the stacking station.

[0033] Advantageously, the system makes it possible to improve the efficiency of the battery cell manufacturing process.

[0034] The system may further comprise one or more of the following features.

[0035] According to one feature, the system comprises: - an assembly vision device configured to control, for each set of electrodes, an alignment between the first electrode and the second electrode of said set, so as to verify whether or not one of said first and second electrodes completely covers the other of said first and second electrodes.

[0036] Advantageously, the assembly vision device makes it possible to check the alignment of the first and second electrodes in order to maximize the capacity of the battery cell.

[0037] According to one characteristic, the assembly vision device may comprise an X-ray camera.

[0038] According to one feature, the stacking station may comprise a stacking platform configured to perform a linear movement in a direction substantially parallel to a stacking direction of the electrode assemblies in the station. stacking platform and configured to support the stacked electrode assemblies, the linear movement of the stacking platform being controlled so as to depend on the running speed of the separator film.

[0039] Advantageously, the linear movement of the stacking platform makes it possible to avoid creases in the separator film.

[0040] According to one feature, the electrode assembly station is configured to implement a rolling such that, for each set of electrodes to be formed, the portion of the separator film of said set of electrodes is rolled with the first electrode of said set of electrodes. Advantageously, the rolling of the first electrode onto the separator film makes it possible to fix the first electrode onto the separator film in order to generate the set of electrodes.

[0041] According to one feature, the laminating station could comprise a heated roller laminator comprising heated rollers.

[0042] Advantageously, the heated roller laminator makes it possible to fix the first and second electrodes on the separator film in order to form a corresponding set of electrodes.

[0043] Other advantages and features will become apparent in the detailed description which follows. Summary description of the drawings

[0044] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0045] [Fig-1] [Fig.l] is a schematic representation of a manufacturing system of a battery cell allowing the implementation according to one embodiment of a method of manufacturing a battery cell.

[0046] [Fig.2] [Fig.2] is a detailed view of the stacking station of the system shown in [Fig.l].

[0047] In these figures, the same reference numerals are used to designate the same elements.

[0048] For reasons of clarity, the figures are not necessarily reproduced to scale. Detailed description

[0049] By “between two values”, it is meant that the limits defined by these two values ​​are included in the range of values ​​considered.

[0050] By insulation is meant electrical insulation.

[0051] By "substantially parallel" is meant parallel or parallel with a margin of error of plus or minus 10%.

[0052] By "substantially orthogonal" is meant orthogonal or orthogonal with a margin of error of plus or minus 10%.

[0053] The invention relates to a method of manufacturing a battery cell.

[0054] The method described comprises the following steps, which can be deduced from Figures 1 and 2: - provide a separator film 103; - forming electrode sets such that each electrode set 3 comprises a first electrode 1, a second electrode 2 of a battery cell and a portion 104 of the separator film 103, said portion 104 of the separator film 103 being interposed between said first electrode 1 and said second electrode 2; - forming, in a stacking station 300 (shown in the dotted frame of [Fig.l]), a stack 305 of electrode assemblies 3, the step of forming the stack comprising multiple folding of the separator film 103; each set of electrodes 3 being formed before the introduction of said set of electrodes 3 into the stacking station 300.

[0055] In particular, it results from the step of forming the stack 305 of sets of electrodes 3 that, for each set of electrodes 3 within said stack 305, the same separator film 103 locally forms the portion 104 of the separator film 103 within said set of electrodes 3. In other words, each set of electrodes 3 comprises its own portion 104 of the separator film 103, said own portion 104 being different from the portion of the separator film included in each of the other sets of electrodes. Advantageously, the method described makes it possible to accelerate the manufacturing process of the battery cell.

[0056] Advantageously, the method described reduces the handling of the separator film 103, thereby reducing the risk of generating creases on the separator film and damaging the separator film 103.

[0057] Advantageously, the method described improves the alignment of the first electrode 1 and the second electrode 2 within the electrode assembly 3 because the electrode assembly 3 is formed before introducing the electrode assembly 3 into the stack of electrode assemblies.

[0058] The method may also be such that, after completion of the stack 305 of electrode assemblies, the separator film 103 is cut to enable the battery cell comprising the stack 305 of electrode assemblies to be obtained from the stacking station 300. Advantageously, this enables the manufacture of a new battery cell within the stacking station 300. In other words, the battery cell comprises, or may comprise, the stack 305 of the electrode assembly.

[0059] According to one embodiment, the separator film 103 is cut using a cutting unit 400, said cutting unit 400 being able to comprise a hot wire or scissors for example in order to obtain the desired cut.

[0060] For each set of electrodes 3, the first electrode 1 and the second electrode 2 may each be chosen from a cathode and an anode. Thus, each set of electrodes comprises an anode and a cathode. For example, the first electrode 1 is an anode for a battery cell and the second electrode 2 is a cathode for the battery cell.

[0061] The separator film 103 may take the form of a strip which is initially wound so as to form a roll 101 capable of feeding the separator film 103. Thus, the separator film 103 may be fed from the roll 101 during the step of supplying the separator film 103.

[0062] The separator film 103 may comprise a mixture of polyethylene or polyvinylidene fluoride, i.e. PVDF, and a ceramic coating and may have a thickness of between 12 μm and 24 μm and a width of between 90 mm and 1200 mm.

[0063] In the final battery, the separator film included in the battery cell is adapted to be impregnated with a liquid solution such as an electrolyte between the electrodes, allowing the circulation of ions.

[0064] The final battery comprises a plurality of battery cells in series each comprising an anode and a cathode.

[0065] Each cathode may comprise a mixture of aluminium and an active material such as NMC 811 - NMC being an abbreviation for a composition of Nickel, Manganese and Cobalt - and a ceramic coating such as an aluminium hydroxide oxide, for example A100H and may have a thickness of between 0.1 mm and 1 mm and a first dimension of between 50 mm and 500 mm and a second dimension, orthogonal to the first dimension, of between 300 mm and 1000 mm. In particular, the cathodes are identical.

[0066] Each anode may comprise a mixture of copper, an active material such as graphite, lithium metal and may have a thickness of between 0.1 mm and 1 mm and a first dimension of between 50 mm and 500 mm and a second dimension, orthogonal to the first dimension, of between 300 mm and 1000 mm. In particular, the anodes are identical.

[0067] In the present description, the first dimension corresponds to the width of the separator film 103 and the second dimension corresponds to the length of the separator film 103 when the corresponding electrode selected from the first electrode 1 and the second electrode 2 is in place relative to the separator film 103 to form a corresponding electrode assembly 3.

[0068] The predefined value between two consecutive first electrodes 1 can for example be chosen between the largest value between the first and the second dimension of the first and the second electrode 1, 2 plus a tolerance range which can have a adequate value to allow the stacking of the first electrode 1 and the second electrode 2 with the interposition of a corresponding separation portion. The tolerance range may be the largest value plus 10%.

[0069] According to the materials mentioned above, the battery cell is preferably intended to form a lithium-ion battery. Thus, within a given battery cell, the separator film 103 is intended to be impregnated with an electrolyte in order to define a plurality of elementary battery cells in series so that between the lower electrode set and the upper electrode set of the corresponding stack of electrode sets, each anode and each cathode is common to two successive elementary battery cells.

[0070] According to one implementation, the method is such that the first electrodes 1 of the battery cell to be manufactured are positioned sequentially on the separator film 103, each first electrode 1 positioned on the separator film 103 being intended to be associated with one of the second electrodes 2 of the battery cell to be manufactured during the step of forming the sets of electrodes 3, said method comprises, for each pair of consecutive first electrodes 1 positioned on the separator film 103, a distance verification step in order to determine whether or not the distance between the two consecutive first electrodes 1 of said pair has a predefined value.

[0071] The predefined value of the distance between two consecutive first electrodes is naturally strictly greater than the dimension of the first electrodes as a function of the length of the separator film 103 so as to allow the superposition of the sets of electrodes by folding the separator film within the stacking station 300.

[0072] The step of forming sets of electrodes may comprise, for each set of electrodes 3 to be formed, a step of rolling the first electrode 1 of said set of electrodes 3 onto the separator film 103 (in particular onto the portion 104 of the separator film 103 intended to form part of a corresponding set of electrodes 3), so that said first electrode 1 is secured to the separator film 103 at the end of said rolling step.

[0073] Advantageously, the rolling of the first electrode 1 onto the separator film 103 makes it possible to fix said first electrode 1 onto the separator film 103 in order to form the electrode assembly 3. The first electrode 1 will therefore have a fixed position relative to the portion 104 of the separator film 3 onto which it is rolled and the alignment with the second electrode 2 to associate it with said first electrode 1 and with said portion 104 of the separator film 3 to form the corresponding electrode assembly 3 is easier to verify. Thus, the rolling step is preferably carried out before the addition of the second electrode 2 within the electrode assembly 3.

[0074] According to one embodiment, in order to form a corresponding set of electrodes, an electrode holder device 602 such as a gripping robot holds the second electrode 2 and brings it against the separator film 103 so that the first electrode 1 and the second electrode 2 are aligned with the interposition of the corresponding portion 104 of the separator film 103. When the first electrode is an anode, said first electrode 1 completely covers said second electrode 2 in order to improve the capacity of the final battery.

[0075] For each set of electrodes 3, the electrode holder device 602 can also be configured to move said set of electrodes 3 towards the stacking station 300 in order to form the stack 305 of set of electrodes.

[0076] The step of forming the sets of electrodes may further comprise a step of checking the assembly such that, for each set of electrodes, an alignment between the first electrode 1 and the second electrode 2 of said set of electrodes 3 is checked so as to verify whether or not one of said first electrode 1 and second electrode 2 entirely covers the other of said first electrode 1 and second electrode 2.

[0077] Advantageously, the assembly control step makes it possible to check the alignment of the first and second electrodes 1, 2 in order to maximize the capacity of the battery cell, and makes it possible to avoid dendrite problems during charging and discharging of the battery.

[0078] The electrode assembly 3 that was checked during the assembly check step can then be moved to the stacking station 300.

[0079] It has been described that the alignment between the first electrode 1 and the second electrode 2 is controlled so as to verify whether or not one of said first electrode 1 and second electrode 2 completely covers the other of said first electrode 1 and second electrode 2. This control can be carried out at different times. In particular, the one of said first and second electrodes 1 and 2 which completely covers the other of said first and second electrodes 1 and 2 is the anode, because the anode must preferably completely cover the cathode to maximize the capacity of the final battery between said first and second electrodes.

[0080] After the assembly inspection step, if the first electrode 1 and the second electrode 2 are not properly aligned or if the first electrode 1 does not completely cover the second electrode 2 when the first electrode 1 is an anode, a defective electrode assembly is obtained. When the defective electrode assembly reaches the stacking station 300, the separator film 103 is cut and the resulting battery cell is discarded.

[0081] The step of forming the stack, as illustrated for example in [Fig.2], may be such that each pair of adjacent electrode sets 303, 304 to the interior of the stack 305 of electrode assemblies comprises two electrode assemblies respectively called first electrode assembly 303 and second electrode assembly 304, the first electrode assembly 303 and the second electrode assembly 304 being stacked with the interposition of a part 306 of a connecting portion 302, said connecting portion 302 being formed by a corresponding part of the separator film 103 and connecting the portion 104 of the separator film 103 of said first electrode assembly 303 to the portion 104 of the separator film 103 of said second electrode assembly 304.

[0082] The interposition of the part 306 of a connecting portion 302 means that the connecting portion 302 is in contact with both the first and second set of electrodes 303, 304.

[0083] Advantageously, the stacking of the first set of electrodes 303 and the second set of electrodes 304 with the interposition of the part 306 of a connecting portion 302 makes it possible to isolate the sets of electrodes within the stack 305.

[0084] The step of forming the stack 305 may comprise a successive introduction of the sets of electrodes to be stacked, according to a direction of introduction of the set of electrodes 3, within the stacking station 300.

[0085] The step of forming the stack of sets of electrodes may comprise a step of controlling the stack such that, for each set of electrodes 3 introduced into the stacking station 300, the alignment between the first electrode 1 and the second electrode 2 is controlled, in particular once again, so as to verify whether or not one of said first electrode 1 and second electrode 2 completely covers the other of said first electrode 1 and second electrode 2 after one of said first or second electrodes 1, 2 has been held and transported by an electrode-holder device 602 to the stacking station 300.If applicable, i.e. when the first electrode 1 is laminated with the separator film 103 and the second electrode 2 is not attached to the separator film 103, the stacking control step can also determine whether or not the second electrode 2 has slipped from its position and thus broken the alignment between the first and second electrodes 1, 2, in particular when the first electrode 1 is laminated with the separator film 103.

[0086] In the event that the alignment check between the first electrode 1 and the second electrode 2 shows that the first electrode 1 and the second electrode 2 are not correctly aligned, or when the first electrode 1 is an anode and does not entirely cover the second electrode 2, the stacking sequence stops automatically and the battery cell being manufactured is scrapped in a scrapping machine where the defective battery cells are placed.

[0087] According to one embodiment, for each set of electrodes 3 introduced into the stacking station 300 after a set of electrodes previously introduced into the stacking station 300, the step of forming the stack of electrode assemblies comprises a first folding of the separator film 103 in a first folding direction and a second folding of the separator film 103 in a second folding direction to enable the stacking of said introduced electrode assembly 3 with the corresponding previously introduced electrode assembly, the first and second folding directions being opposite.

[0088] Advantageously, the first and second folding of the separator film 103 makes it possible to isolate sets of electrodes within the stack 305 while limiting the dimension of the separator film 103 between two adjacent stacked sets of electrodes 303, 304.

[0089] According to one embodiment, for each set of electrodes 3 introduced into the stacking station 300 after a set of electrodes previously introduced into the stacking station 300, the step of forming the stack 305 of sets of electrodes comprises a displacement of said set of electrodes previously introduced to allow the stacking of said set of electrodes introduced with said set of electrodes previously introduced in particular such that said set of electrodes introduced is arranged, when stacked with said set of electrodes previously introduced, on the position of said set of electrodes previously introduced before said displacement.

[0090] Advantageously, the movement of said previously introduced set of electrodes makes it possible to avoid creases in the separator film.

[0091] The stacking station 300, like that shown in [Fig. 2], may comprise a stacking platform 301 configured to perform a linear movement F1 in a direction substantially parallel to a stacking direction of the electrode assemblies in the assembly station 300 and configured to support the electrode assembly 3, and in which each movement is performed by the linear movement F1 of the stacking platform 301. In other words, the stacking station 300 is configured to support the battery cell as it is manufactured by successively introducing and stacking the electrode assembly 3 inside the stacking station 300. The speed of the linear movement F1 may be correlated to the running speed of the separator film 103 so as to avoid the formation of wrinkles on the separator film 103 as long as the stacking platform 301 descends at the correct speed. speed.

[0092] Advantageously, the linear movement F1 of the stacking platform 301 allows the displacement of said previous set of electrodes to allow the stacking of each set of electrodes introduced last into the stacking station 300 on a set of electrodes introduced previously into the stacking station 300.

[0093] In particular, the first of the sets of electrodes introduced into the stacking station 300 is arranged on the stacking platform 301 and the other sets of electrodes introduced are then stacked successively above the first of the electrodes introduced.

[0094] The stacking platform 301 may be configured to perform a linear movement F1 in a direction substantially orthogonal to a direction of introduction of the electrode assembly into the assembly station 300. This has the advantage of preventing the formation of folds on the separator film.

[0095] The invention also relates to a system 1000 for manufacturing a battery cell shown in [Fig.l], said system 1000 comprising: - a separator film supply station 100 (shown in the dotted frame in [Fig.l]); - an electrode assembly station 200 (shown in dotted lines in [Fig.l]) configured to form electrode sets such that each electrode set 3 comprises the first electrode 1, the second electrode 2 and the portion 104 of the separator film 103, said portion 104 of the separator film 103 being interposed between said first electrode 1 and second electrode 2; and - a stacking station 300, in particular as described above in relation to the manufacturing method, in which the stack of electrode assemblies is intended to be formed by multiple folding of the separator film 103. In other words, the stacking station is configured to receive the stack of electrode assemblies.

[0096] The system 1000 described is configured so as to allow the separator film 103 to travel from the supply station 100 to the stacking station 300 and the electrode assembly station 200 is arranged so as to be traversed by the separator film 103 between the separator film supply station 100 and the stacking station 300. In other words, the electrode assembly station 200 cooperates with the separator film 103 so as to form each set of electrodes 3 before said set of electrodes 3 enters the stacking station 300.

[0097] As shown in [Fig.l], the separator film supply station 100 may comprise the roller 101 continuously supplying the separator film 103 and a pulley 102 configured to bend the separator film 103 to guide it toward the electrode assembly station 200.

[0098] According to one embodiment, the electrode assembly station 200 is configured to implement a rolling such that, for each set of electrodes 3 to be formed, the portion 104 of the separator film 103 of said set of electrodes 3 is rolled with the first electrode 1 of said set of electrodes 3. The result of this rolling is in particular that the corresponding first electrode 1 is secured to the corresponding portion 104 of the separator film 103. In other words, for each electrode assembly 3 to be formed in the electrode assembly station 200, said electrode assembly station 200 is configured to laminate together the first electrode 1 of said electrode assembly 3 to be formed and the separator film 103.

[0099] To implement the above-mentioned rolling, the electrode assembly station 200 may comprise a heated roller laminator 202 comprising heated rollers 201.

[0100] The heated roller laminator 202 is configured to laminate the first electrode 1 of a corresponding electrode assembly to be formed with the separator film 103.

[0101] The first electrode 1 may be supplied by an electrode supply device 601 such as a gripping robot. The electrode supply device 601 may be configured to successively add first electrodes onto the separator film 103 before associating a corresponding second electrode 2 to form a respective electrode assembly 3 to be integrated into the battery cell.

[0102] For each set of electrodes 3 to be formed, once the first electrode 1 has been laminated onto the separator film 103, an electrode-holder device 602, in particular such as the electrode-holder device 602 described above in relation to the manufacturing method, could provide the second electrode 2 of said set of electrodes 3 in order to bring said second electrode into contact with the separator film 103 so that the first electrode 1 and the second electrode 2 are aligned and the separator film 103 is locally interposed, via the corresponding portion 104 of the separator film 103, between the first electrode 1 and the second electrode 2.

[0103] According to one embodiment, the second electrode 2 can also be laminated on the separator film 103.

[0104] Advantageously, the rolling of the second electrode 2 onto the separator film 103 makes it possible to fix the second electrode 2 onto the separator film 103, thus limiting the risk of the second electrode 2 slipping and of breaking the alignment between the first electrode 1 and the second electrode 2.

[0105] According to one embodiment, the system 1000 may comprise a distance vision device 501 configured to verify that, for each pair of first electrodes to be included in the battery cell and positioned sequentially on the separator film 103, the distance between the first consecutive electrodes of said pair placed on the separator film 103 has a predefined value. This distance vision device 501 is thus in particular configured to implement the distance verification step of the manufacturing method. Advantageously, the distance vision device 501 makes it possible to verify that the distance between two consecutive first electrodes has a predefined value.

[0106] The system 1000 may also include an assembly vision device. 502 configured to control, for each set of electrodes 3, an alignment between the first electrode 1 and the second electrode 2 of said set 3, so as to verify whether or not one of said first electrode 1 and second electrode 2 completely covers the other of said first electrode 1 and second electrode 2. Such an assembly vision device 502 can be arranged at the outlet of the electrode assembly station 200.

[0107] According to one embodiment, the system 1000 may further comprise a stacking vision device 503 configured to control, for each set of electrodes 3 introduced into the stacking station 200, the alignment between the first electrode 1 and the second electrode 2 so as to verify whether or not the first electrode 1 completely covers the second electrode 2 after said second electrode 2 has been held and transported by the electrode holder device 602. The stacking vision device 503 may also determine whether or not the second electrode 2 has slipped from its position and therefore broken the alignment between the first and second electrodes 1, 2 after said second electrode 2 has been held and transported by the electrode holder device 602 from the electrode assembly station 200 to the stacking station 300.Thus, the stacking vision device 503 can be configured to implement the stacking control step mentioned above. Advantageously, the vision devices 502, 503 make it possible to check the alignment of the electrodes in order to maximize the capacity of the battery cell.

[0108] Each vision device 501, 502, 503 may comprise a camera, and in particular an X-ray camera.

[0109] In the case where the distance vision device 501 indicates that the distance between two consecutive first electrodes on the separator film 103 does not have a predefined value, or if the vision devices 502, 503 indicate that the alignment between the first and second electrodes 1, 2 is not verified or that the first electrode 1 does not completely cover the second electrode 2, a defective electrode set is obtained. When the defective electrode set reaches the stacking station 300, the separator film 103 is cut and the resulting battery cell, or the portion of the battery cell, in the stacking station is discarded.

[0110] The stacking station 300 may comprise a stacking platform 301, in particular such as that described in relation to the manufacturing method, configured to perform a linear movement F1 in a direction substantially parallel to a stacking direction of the electrode assemblies in the stacking station 300 and configured to support the stacked electrode assemblies. The linear movement F1 of the stacking platform 301 is controlled so as to depend on the running speed of the separator film 103.

[0111] Preferably, this dependence of the linear motion Fl on the speed of The movement of the separator film 103 is electronically controlled. In fact, the control can be carried out by a computer which monitors the speed of the linear movement Fl and the movement speed of the separator film 103 in order to maintain the desired values.

[0112] The linear movement Fl can be generated by a servomotor.

[0113] Advantageously, the linear movement F1 of the stacking platform 301 makes it possible to avoid creases in the separator film.

[0114] The manufacturing method and system described above have an industrial application in the field of batteries.

[0115] What applies in this detailed description to the manufacturing process also applies to the system 1000, and vice versa.

[0116] Although the invention has been described in relation to particular embodiments, it is obvious that it is in no way limited thereto and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

Claims

Claims

1. A method of manufacturing a battery cell, said method comprising the following steps: - providing a separator film (103); - forming electrode sets such that each electrode set (3) comprises a first electrode (1), a second electrode (2) and a portion (104) of the separator film (103), said portion (104) of the separator film (103) being interposed between said first electrode (1) and said second electrode (2); - forming, in a stacking station (300), a stack (305) of electrode assemblies (3), the step of forming the stack comprising multiple folding of the separator film (103); each set of electrodes (3) being formed before the introduction of said set of electrodes (3) into the stacking station (300); and wherein, for each electrode assembly (3) introduced into the stacking station (300) after a previously introduced electrode assembly into the stacking station (300), the step of forming the stack (305) of electrode assemblies comprises a displacement of said previously introduced electrode assembly to enable stacking of said introduced electrode assembly with said previously introduced electrode assembly, the stacking station (300) comprising a stacking platform (301) configured to perform a linear movement (F1) in a direction substantially parallel to a stacking direction of the electrode assemblies in the stacking station (300) and configured to support the electrode assembly (3), each displacement being performed by the linear movement (F1) of the stacking platform (301), the speed of the linear movement (F1) of the stacking platform (301) being adapted to the running speed of the separating film (103),the stacking platform (301) being configured to perform the linear movement (Fl) in a direction substantially orthogonal to a direction of introduction of the set of electrodes into the stacking station (300).,

2. The method of claim 1, wherein the step of forming the stack is such that each pair of adjacent electrode sets (303, 304) within the stack (305) of electrode sets comprises two electrode sets respectively called first electrode set (303) and second electrode set of electrodes (304), the first set of electrodes (303) and the second set of electrodes (304) being stacked with the interposition of a part (306) of a connecting portion (302), said connecting portion (302) being formed by a corresponding part of the separator film (103) and connecting the portion (104) of the separator film (103) of said first set of electrodes (303) to the portion (104) of the separator film (103) of said second set of electrodes (304).

3. A method according to any one of claims 1 to 2, wherein, for each electrode set (3) introduced into the stacking station (300) after a previously introduced electrode set into the stacking station (300), the step of forming the stack of electrode sets comprises a first folding of the separator film (103) in a first folding direction and a second folding of the separator film (103) in a second folding direction to enable stacking of said introduced electrode set (3) with the corresponding previously introduced electrode set, the first and second folding directions being opposite.

4. Method according to any one of claims 1 to 3, wherein the first electrodes (1) of the battery cell to be manufactured are positioned sequentially on the separator film (103), each first electrode (1) positioned on the separator film (103) being intended to be associated with one of the second electrodes (2) of the battery cell to be manufactured during the step of forming the electrode assemblies (3), said method comprises, for each pair of consecutive first electrodes (1) positioned on the separator film (103), a distance verification step in order to determine whether the distance between the two consecutive first electrodes of said pair has a predefined value or not.

5. A method according to any one of claims 1 to 4, wherein the step of forming the electrode assemblies comprises a step of checking the assembly such that, for each electrode assembly, an alignment between the first electrode (1) and the second electrode (2) of said electrode assembly (3) is checked so as to verify whether or not one of said first electrode (1) and second electrode (2) completely covers the other of said first electrode (1) and second electrode (2).

6. A method according to any one of claims 1 to 5, wherein the step of forming the stack of electrode assemblies comprises a stacking control step such that, for each set of electrodes (3) introduced into the stacking station (300), the alignment between the first electrode (1) and the second electrode (2) is controlled so as to verify whether or not one of said first electrode (1) and second electrode (2) completely covers the other of said first electrode (1) and second electrode (2) after one of said first or second electrodes (1, 2) has been held and transported by an electrode holder device (602) towards the stacking station (300).

7. A method according to any one of claims 1 to 6, wherein the step of forming electrode assemblies comprises, for each electrode assembly (3) to be formed, a step of rolling the first electrode (1) of said electrode assembly (3) onto the separator film (103), so that said first electrode (1) is secured to the separator film (103) at the end of said rolling step.

8. A method according to any one of claims 1 to 7, wherein, after completion of the stacking of electrode assemblies, the separator film (103) is cut to enable the battery cell comprising the stack (305) of electrode assemblies to be obtained from the stacking station (300).

9. System (1000) for manufacturing a battery cell, said system (1000) comprising: - a separator film supply station (100); - an electrode assembly station (200) configured to form electrode assemblies such that each electrode assembly (3) comprises a first electrode (1), a second electrode (2) and a portion of the separator film (103), said portion (104) of the separator film (103) being interposed between said first electrode (1) and said second electrode (2); and - a stacking station (300) in which a stack of electrode assemblies is intended to be formed by multiple folding of the separator film (103);said system (1000) being configured to allow the separator film (103) to travel from the supply station (100) to the stacking station (300), the electrode assembly station (200) being arranged so as to be crossed by the separator film (103) between the separator film (103) supply station (100) and the stacking station (300), the stacking station (300) comprising a stacking platform (301) configured to perform a linear movement (Fl) in a substantially direction; parallel to a stacking direction of the electrode assemblies in the stacking station (300) and configured to support the stacked electrode assemblies, the linear movement (Fl) of the stacking platform (301) being controlled so as to depend on the running speed of the separator film (103), the stacking platform (301) being configured to carry out the linear movement (Fl) in a direction substantially orthogonal to a direction of introduction of the electrode assembly into the stacking station (300).

10. System (1000) according to claim 9, wherein it comprises an assembly vision device (502) configured to control, for each set of electrodes (3), an alignment between the first electrode (1) and the second electrode (2) of said set (3), so as to verify whether or not one of said first electrode (1) and second electrode (2) entirely covers the other of said first electrode (1) and second electrode (2).

11. System (1000) according to any one of claims 9 to 10, wherein the electrode assembly station (200) is configured to implement lamination such that, for each set of electrodes (3) to be formed, the portion of the separator film (103) of said set of electrodes (3) is laminated with the first electrode (1) of said set of electrodes (3).

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