Warehouse for the formation of electrochemical cells and method for at least partially forming electrochemical cells

Abstract

A warehouse (10) for the formation of electrochemical cells (100), comprising a containment structure (12) within which are housed: a plurality of formation modules (16), a plurality of drawers (20), a plurality of formation stations (15) and at least one service station (27); wherein each formation module (16) is configured to be coupled to a cell tray (11) to implement an at least partial formation cycle of electrochemical cells (100) contained in the cell tray (11); wherein at least part of at least one formation module (16) of the plurality of formation modules (16) is placed in each drawer (20) of at least one group of drawers of the plurality of drawers (20); wherein each drawer (20) of the at least one group of drawers (20) is movable within the containment structure (12) between at least one formation station (15) and the service station (27).

Description

[0001] Warehouse for the formation of electrochemical cells and method for at least partially forming electrochemical cells DESCRIPTION

[0002] The present invention relates to a warehouse for the formation of electrochemical cells and a method for at least partial forming electrochemical cells.

[0003] The present invention finds particular application in the production of secondary batteries, preferably rechargeable lithium batteries. Although in the course of this description, reference will be made specifically to lithium electrochemical cells, the teachings of the present invention also apply to the case of other secondary electrochemical cells.

[0004] In the production of lithium electrochemical cells, after mechanical assembly operations of the electrochemical cells, the electrochemical cells have to undergo electrical operations that lead to electrochemical phenomena within the electrochemical cells such that the anodes are covered by the so-called "Solid Electrolyte Interphase" (SEI). These operations are known in the technical sector by the term "formation" of the electrochemical cells.

[0005] The electrochemical cell formation operations typically involve a succession of charge / discharge cycles of the electrochemical cells applying currents of 0.1 -0.2 C for predetermined times (on the order of 10-24 hours). The magnitude "C" indicates a current value expressed in amperes numerically equal to the cell capacity in Ah (e.g. for a cell capacity of 2 Ah, the magnitude C is 2 A). The currents actually applied, the charge / discharge times and the number of repetitions of the various charge / discharge cycles depend on the type of battery and each battery manufacturer has developed its own "recipe" that allows to best form the electrode surface layer SEI to maximise battery performance. In fact, only if the formation process is performed properly will the electrode surface layer SEI be deposited on the electrodes of the battery, which optimizes the properties of the battery in terms of charge capacity and uniformity of charge / discharge cycles.

[0006] After the formation operations, the formed electrochemical cells are subjected to electrically passive aging operations, carried out in special resting stations (aging stations) for times in the order of tens or hundreds of hours, in which the cells are allowed "to rest" to allow them to stabilise at specially controlled temperatures.

[0007] In the Applicant's experience, the formation of the electrochemical cells is performed in a formation plant in which cell trays, each containing a plurality of electrochemical cells arranged in a matrix pattern, are positioned in respective formation chambers.

[0008] In the Applicant's experience, in the formation plants the formation chambers are arranged in cabinets, known by the term "rack". Inside each formation chamber a contacting assembly is placed, configured to enter into electrical contact with each electrochemical cell of the cell tray. A plurality of contacting assemblies, typically the contacting assemblies of the formation chambers of a shelf of the rack, is connected via a plurality of electrical cables to the electrical and electronic components necessary to provide electrical power to the contacting assembly to implement the charge / discharge cycles of the electrochemical cells.

[0009] In the Applicant's experience, the powers used for the formation of a group of 64 electrochemical cells are of the order of 5-6 kW and, considering that the groups of electrochemical cells that are formed in a formation rack can be tens or even hundreds, high electrical powers are required that must be delivered and controlled by the electrical and electronic components necessary to supply electrical power to the contacting assemblies.

[0010] It may therefore be necessary to subject to maintenance cycles, either periodically or occasionally, the electrical and electronic components necessary to supply electrical power to the contacting assemblies.

[0011] During a formation process it can also happen that, for example due to small inaccuracies in the mechanical assembly process of the electrochemical cells, in some electrochemical cells being formed the temperature increases exponentially causing a so-called thermal runaway which, even if promptly counteracted, could cause the contacting assembly on the electrochemical cells to melt.

[0012] The Applicant has noted that in the cases described above and also for other possible reasons, it may be necessary to access the electrical and electronic components necessary to supply electrical power to the contacting assembly or in combination to access the contacting assemblies placed inside the rack.

[0013] The Applicant has found in order to be able to access the inside of the rack, given the high electrical powers used, it is necessary to secure the latter by disconnecting the rack from the electrical grid in such a way that specialized operators can reach the contacting assembly and the electrical and electronic components and perform maintenance or restoration operations in total safety.

[0014] The Applicant has however noted that this may require careful planning of maintenance times.

[0015] In fact, if there were electrochemical cells on which the formation process is running, the interruption of the formation process caused by disconnection from the electrical grid of the rack would irreparably compromise the execution of the formation recipe with consequent compromise and discard of these electrochemical cells.

[0016] Therefore, in the Applicant's experience it is advisable to wait for the completion of the formation process of all the electrochemical cells present in the rack before being able to proceed with maintenance operations. Considering that the formation process does not necessarily start at the same time in all the formation chambers of the rack, managing maintenance timing and logistics can be very expensive and complicated.

[0017] Furthermore, the Applicant found that in the event that an immediate maintenance or restoration intervention was required, for example in the case of thermal runaway of a group of electrochemical cells, it would not be possible to avoid interrupting the formation process of the remaining electrochemical cells within the rack with consequent compromise and discard of these electrochemical cells.

[0018] The Applicant has therefore felt the need to make available a formation warehouse that allows a relatively easy and inexpensive execution of maintenance and possibly restoration operations of the contacting assemblies or in combination of the electrical and electronic components necessary to supply electrical power to the contacting assemblies.

[0019] The Applicant has perceived that if at least the components subject to maintenance and whose access is particularly expensive were made movable within the rack, these components could be brought if necessary into easily accessible positions in order to be able to perform the relative maintenance operations without the need to interrupt the functionality of the entire rack so that these components to be maintained can be accessed.

[0020] The Applicant has therefore found that by arranging a warehouse comprising a plurality of drawers on which at least some components of formation modules are arranged and by making these drawers movable within the warehouse it would be possible, in the event of maintenance and / or restoration of such components, to move the only drawer bearing the components to be maintained into a position of easy access without necessarily having to interrupt all the formation processes taking place in the warehouse to allow safe access to the components subject to maintenance.

[0021] The present invention therefore concerns, in a first aspect thereof, a warehouse for the formation of electrochemical cells.

[0022] Preferably, the warehouse comprises a containment structure.

[0023] Preferably, a plurality of formation modules are housed within the containment structure.

[0024] Preferably, a plurality of drawers are housed within the containment structure.

[0025] Preferably, a plurality of formation stations are housed within the containment structure.

[0026] Preferably, at least one service station is housed within the containment structure.

[0027] Preferably, each formation module is configured to be coupled to a cell tray to implement an at least partial formation cycle of electrochemical cells contained in said cell tray.

[0028] Preferably, at least part of at least one formation module of said plurality of formation modules is placed in each drawer, of at least one group of drawers of said plurality of drawers.

[0029] Preferably, each drawer of said at least one group of drawers is movable within said containment structure between said at least one formation station of said plurality of formation stations and said at least one service station.

[0030] In this way, it is possible to move the drawer, containing the part of the at least one formation module that must be subjected to maintenance, from the formation station to the service station and carry out the maintenance and / or restoration operations without necessarily having to interrupt the formation activity of all the remaining warehouse formation modules or to wait for the completion of the formation process of all the formation modules of the warehouse. The Applicant has also observed that making the drawers movable within the warehouse between the respective formation stations and the service station allows not to limit the warehouse in height, as the drawers can be placed at any height within the warehouse, not having to be reached by maintenance operators to carry out maintenance operations.

[0031] The present invention concerns, in a second aspect thereof, a method for at least partial forming electrochemical cells.

[0032] Preferably, it is provided a warehouse in accordance with the first aspect of the present invention.

[0033] Preferably, it is provided for coupling a cell tray containing electrochemical cells to a formation module placed in a drawer inserted in a formation station.

[0034] Preferably, it is provided for actuating at least a partial formation cycle of the electrochemical cells.

[0035] Preferably, in case it is necessary to carry out maintenance operations on the formation module it is provided for: moving the drawer from the formation station to the service station; carrying out maintenance operations on said formation module when the drawer is placed in the service station.

[0036] Preferably, it is provided for, at the end of the maintenance operations, moving the drawer from the service station to the formation station.

[0037] By "electrochemical cell" is meant an assembly consisting of at least one anode, one cathode, a possible separator made of dielectric material interposed between the anode and cathode, and an electrolyte. A battery comprises at least one electrochemical cell.

[0038] By "formation" is meant a process in which an electrochemical cell is subjected to charge / discharge / recharge cycles. The currents applied during charge / discharge / recharge cycles, measured in Amperes, are numerically of a lower order of magnitude than the number expressing the total capacity in Ah of the electrochemical cell. For example, when an electrochemical cell has a capacity of 1 Ah, the maximum currents applied are about 0.1 - 0.2 amperes. The charge / discharge / recharge cycles are implemented for such a time (e.g. 12-24 hours) to reach maximum voltage, minimum voltage, and then return the electrochemical cell to a known state of charge, typically 80%. By "bi-directional converter" is meant a power supply device capable of supplying electrical energy to a user device and extracting energy from it, enabling a bidirectional exchange of energy between the user device and the power supply device. In a bi-directional converter the direction of the electrical energy flow is directed in a controlled manner either from the power supply device towards the user device or from the user device towards the power supply device; there is never a possibility that the energy flow is simultaneously directed from the power supply device towards the user device and from the user device towards the power supply device.

[0039] By "drawer" is meant any support structure capable of supporting one or more bodies and inserted into a housing compartment, not necessarily closed on the sides and not necessarily slidable on guides or the like in order to be able to be extracted from a housing compartment.

[0040] By "conditioning" or "thermally conditioning" a physical entity (such as for example a tray, a formation module, a liquid) is meant subjecting that physical entity to a thermal heating or cooling action.

[0041] The present invention may have at least one of the preferred features described below. Such features may be present individually or in combination with each other, unless expressly stated otherwise.

[0042] The formation stations are preferably positions within the warehouse occupied by the drawers when the electrochemical cell formation operations are carried out.

[0043] Preferably, the service station is configured to allow direct access to a drawer when placed in the service station.

[0044] Preferably, said service station comprises an opening to expose a drawer of said at least one group of drawers, when placed in the service station, to an environment external to an inner volume of said containment structure.

[0045] Preferably, the service station is configured to receive only one drawer at a time.

[0046] Preferably, said part of at least one formation module placed in said drawer moves together with the drawer, transported by said drawer, when the drawer is moved between the respective formation station and the service station.

[0047] Preferably, said part of at least one formation module placed in said drawer moves together with the drawer, transported by said drawer, when the drawer is moved between the service station and the respective formation station.

[0048] Preferably, when a drawer is placed in the service station, the formation modules of other drawers placed in respective formation stations can perform formation operations on electrochemical cells.

[0049] Preferably, the service station is located, within the containment structure, at an elevation with respect to a baseplate of the warehouse, directly reachable by an operator.

[0050] Preferably, at said opening of the service station there is provided a gate configured to prevent access to said opening when said gate is in a closed condition and to allow access to said opening when said gate is in an open condition.

[0051] Preferably, each drawer of said at least one group of drawers is movable within said containment structure independently of any other drawer of said at least one group of drawers.

[0052] In the preferred embodiment of the invention, only one respective drawer is provided in each formation station.

[0053] In the preferred embodiment of the invention, all the drawers of said plurality of drawers are movable between a respective formation station and the service station and between the service station and a respective formation station.

[0054] Preferably, all the drawers of said plurality of drawers are movable independently of each other between a respective formation station and the service station and between the service station and a respective formation station.

[0055] Preferably, all the drawers of said plurality of drawers are movable one at a time between a respective formation station and the service station and between the service station and a respective formation station.

[0056] Preferably, within said containment structure, a transport system is housed for transferring each drawer of said at least one group of drawers between a respective formation station and said service station and between said service station and said respective formation station.

[0057] Preferably, the transport system is configured to pick up a drawer from a respective formation station, transfer it at the service station and to insert it into the service station.

[0058] Preferably, the transport system is further configured to pick up a drawer from the service station, transfer it at a formation station and to insert it into the formation station.

[0059] Preferably, the transport system is active on one drawer at a time.

[0060] Preferably, when a drawer is present in the service station, the transport system cannot pick up any other drawer from a respective formation station.

[0061] In some embodiments, the transport system is further configured to move at least one drawer within said containment structure between two formation stations of said plurality of formation stations.

[0062] Preferably, the transport system comprises a movable lift within the containment structure.

[0063] Preferably, the lift comprises a resting structure sized to transport one drawer at a time within the warehouse.

[0064] In the preferred embodiment of the invention, the formation stations are placed within the warehouse above the service station.

[0065] Preferably, when a drawer is placed inside a formation station, said drawer is not accessible from an environment external to the containment structure of the warehouse.

[0066] Preferably, each drawer is movable within the containment structure only between the formation stations and the service station and between the service station and the formation stations.

[0067] Preferably, when a drawer is placed in the service station, said part of at least one formation module placed in said drawer is accessible through said opening of the service station.

[0068] In the preferred embodiment of the invention, at least one formation module is placed in each drawer of said group of movable drawers within said containment structure.

[0069] Preferably, each formation module comprises a contacting assembly configured to provide an electrical contact for each of said electrochemical cells housed in a cell tray.

[0070] Preferably, said contacting assembly comprises a plurality of electrical contacts configured to enter into electrical contact relationship with poles of the electrochemical cells.

[0071] Preferably, each formation module further comprises at least one bi-directional converter in electrical connection with said contacting assembly.

[0072] Preferably, each formation module comprises a bi-directional converter for each electrochemical cell present in a cell tray.

[0073] Preferably, a plurality of formation modules are placed in each drawer of said group of movable drawers within said containment structure.

[0074] Preferably, the formation modules placed in a drawer move together with the drawer when the drawer is moved between the respective formation station and the service station.

[0075] Preferably, the formation modules placed in a drawer move together with the drawer when the drawer is moved between the service station and the respective formation station.

[0076] Preferably, each bi-directional converter of a formation module is placed in electrical connection with an electrical power source when the respective drawer is in a respective formation station.

[0077] Preferably, each bi-directional converter of a formation module is disconnected from said electrical power source when the respective drawer is moved between the respective formation station and the service station and between the service station and the respective formation station.

[0078] Preferably, at least one electrical quick-coupling connector is placed in each formation station to put said electrical power source in electrical connection with each bi-directional converter of the formation modules placed in a drawer.

[0079] Preferably, when a drawer is placed in a respective formation station, each bidirectional converter of the formation modules placed in a drawer is placed in electrical connection with said electrical power source through said electrical quick-coupling connector. The Applicant has noted that the drawers can also be used to simultaneously connect all the formation modules to the electrical connector present in the formation station. In this way it is possible to reduce the number of electrical connectors present in each formation station up to even one single electrical connector.

[0080] For this purpose, preferably, each drawer of said group of movable drawers inside the containment structure comprises at least one electrical plug configured to connect with said at least one electrical quick-coupling connector of a formation station.

[0081] Preferably, said at least one electrical plug is placed in electrical connection, preferably permanently, with all the bi-directional converters of the formation modules placed in said drawer.

[0082] Preferably, when the transport system picks up a drawer from a formation station, the at least one electrical plug of said drawer is disconnected from said at least one electrical quick-coupling connector placed in the formation station.

[0083] Preferably, when the transport system inserts a drawer into a formation station, the at least one electrical plug of said drawer is connected to said at least one electrical quick-coupling connector placed in the formation station.

[0084] Preferably, at least one electrical quick-coupling connector is placed in said service station, configured to put said electrical power source in electrical connection with each bi-directional converter of the formation modules placed in a drawer when said drawer is placed in the service station.

[0085] Preferably, when the transport system inserts a drawer into the service station, the at least one electrical plug of said drawer is connected to said at least one electrical quick-coupling connector placed in the service station.

[0086] Preferably, when the transport system picks up a drawer from the service station, the at least one electrical plug of said drawer is disconnected from said at least one electrical quick-coupling connector placed in the service station.

[0087] Preferably, the warehouse further comprises a transfer station configured to interface between an inner volume of said containment structure and an environment external to said inner volume of said containment structure.

[0088] Preferably, the transfer station is further configured to receive cell trays from said external environment and to deliver cell trays from said inner volume to said external environment.

[0089] Preferably, said service station is placed along a wall of said warehouse other than a wall along which said transfer station is placed.

[0090] The Applicant has perceived that the transport system used to move and transport the drawers within the warehouse can also be used to move and transport the cell trays within the warehouse.

[0091] The Applicant has therefore found that in some embodiments, regardless of the presence of the test station, it is possible to use the same transport system to move said drawers within the containment structure and between the formation stations and to move the cell trays within the containment structure between the formation stations.

[0092] In this way it is possible to reduce the space required inside the warehouse to move the drawers and the cell trays.

[0093] Preferably, the transport system is further configured to transfer cell trays containing electrochemical cells inside said containment structure between said transfer station and drawers placed in the formation stations and between said drawers placed in the formation stations and said transfer station.

[0094] Preferably, the transport system is further configured to position a tray of electrochemical cells in proximity to a contacting assembly of a formation module of a drawer placed in a respective formation station.

[0095] Preferably, the transport system is further configured to pick up a tray of electrochemical cells from a contacting assembly of a drawer formation module located in a respective formation station.

[0096] Preferably, the warehouse is part of a battery production plant comprising a plurality of cell trays each containing electrochemical cells.

[0097] Preferably, the containment structure comprises a frame and a plurality of possibly removable walls delimiting the inner volume of the warehouse.

[0098] In some embodiments, a plurality of transfer stations may be provided, wherein some transfer stations are configured to receive cell trays and other transfer stations are configured to extract cell trays from the warehouse. In the preferred embodiment of the invention, a single transfer station is used both to receive cell trays and to extract cell trays from the warehouse.

[0099] Preferably, associating said cell tray with a formation module comprises contacting the electrochemical cells contained in the cell tray with said contacting assembly.

[0100] Preferably, said formation stations are arranged one on top of the other in at least one column of formation stations.

[0101] Preferably, said transfer station is below said formation stations.

[0102] Preferably, a plurality of columns of formation stations are present.

[0103] The Applicant has noted that during the formation process it may be necessary to actively control the temperature of the electrochemical cells. This, for example, in order to prevent the temperature of the electrochemical cells from rising too high, leading for example to a thermal runaway.

[0104] The Applicant has also noted that, depending on the formation "recipe" to be implemented, it may be necessary to ensure that the electrochemical cells remain at predetermined temperatures or predetermined temperature intervals at predetermined steps of the formation process.

[0105] For this purpose, the Applicant has perceived that the formation warehouse could be used as an incubator for the electrochemical cells being formed.

[0106] Therefore, preferably the warehouse comprises a thermal conditioning system configured to thermally condition cell trays placed in the formation stations.

[0107] Preferably, said thermal conditioning system is configured to thermally condition at least at a first formation temperature the cell trays placed in the formation station.

[0108] Preferably, the thermal conditioning system comprises a warehouse conditioning circuit.

[0109] Preferably, the warehouse conditioning circuit is placed in fluid connection with a fluid conditioner.

[0110] The fluid conditioner may be internal to the warehouse containment structure or external to the warehouse containment structure. Preferably, a conditioning liquid circulates within the warehouse conditioning circuit.

[0111] Preferably, the conditioning liquid is optionally demineralised, osmotised or distilled water.

[0112] Preferably, said conditioning system is configured to thermally and selectively associate said fluid conditioner with said cell trays.

[0113] Preferably, said warehouse conditioning circuit does not act on said transfer station.

[0114] Preferably, when a cell tray is inserted in a respective formation station, it is provided to hydraulically connect said warehouse conditioning circuit with a cell tray conditioning circuit.

[0115] Preferably, during the movement of a cell tray operated by the transport system, the cell tray conditioning circuit is not hydraulically connected with said warehouse conditioning circuit.

[0116] The Applicant has rushed that the conditioning system could also be used to cool (or if necessary heat) the formation modules.

[0117] In this regard, preferably said conditioning system further comprises a formation module conditioning circuit for each formation module.

[0118] Preferably, said formation module conditioning circuit is placed in fluid connection with said warehouse conditioning circuit at least when said formation module is in use to implement a formation process.

[0119] Preferably, at each formation station there is placed at least one quick-coupling hydraulic connector for hydraulically connecting said warehouse conditioning circuit with said formation module conditioning circuit and with said cell tray conditioning hydraulic circuit and for disconnecting said warehouse conditioning circuit from said formation module conditioning circuit and from said cell tray conditioning hydraulic circuit.

[0120] Preferably, during the movement of a drawer from the formation station to the service station and from the service station to the formation station, the formation module conditioning circuit is not hydraulically connected with said warehouse conditioning circuit. The Applicant considers that hydraulically connecting the formation module conditioning circuit to the warehouse conditioning circuit only when the drawer is in a formation station confers high flexibility and high ease of use of the warehouse in performing the formation operations. In fact, each drawer can be moved within the warehouse without being hydraulically connected to the warehouse conditioning circuit, thus avoiding having to have to provide for complicated and expensive hydraulic connections between the warehouse conditioning circuit and the formation module conditioning circuit.

[0121] Further characteristics and advantages of the present invention will become clearer from the following detailed description of some preferred embodiments, with reference to the appended drawings and provided by way of indicative and non-limiting example, in which:

[0122] Figures 1 and 2 are schematic perspective views of a warehouse for the process of formation of electrochemical cells in accordance with the present invention;

[0123] Figure 3 is a first schematic representation of the interior of the warehouse of Figure 1 ;

[0124] Figure 4 is a second schematic representation of the interior of the warehouse of Figure 1 ;

[0125] Figure 5 is a schematic perspective view of a drawer used in the warehouse of Figure 1 ;

[0126] Figure 6 is a schematic perspective view of a formation module placed in a drawer;

[0127] Figure 7 is a schematic representation of some components of the drawer of Figure 6;

[0128] Figure 8 is a schematic representation of an electrical diagram of the warehouse of Figure 1 ;

[0129] Figure 9 is a schematic representation of a thermal conditioning system, and some of its components, of the warehouse of Figure 1 ; and

[0130] Figure 10 is a schematic representation of a cell tray. The representations in the appended figures must not be understood in scale, do not necessarily respect the proportions between the various parts and must be purely understood as diagrams.

[0131] With initial reference to Figure 1 , 10 indicates as a whole a warehouse for the process for forming electrochemical cells in accordance with the present invention.

[0132] The warehouse 10 is arranged to receive cell trays 11 containing electrochemical cells 100 (schematized in Figure 10), for example coming from an upstream packaging plant, not represented, and to subject the electrochemical cells 100 to a formation process. The electrochemical cells 100 are lithium ions secondary electrochemical cells.

[0133] Each cell tray 1 1 has a generally box-like shape, and comprises a plurality of housings for containing, preferably separated from each other, a plurality of electrochemical cells 100.

[0134] The warehouse 10 comprises a containment structure 12 having a plurality of walls 13 that are fixed, preferably removably, to a frame. The containment structure 12 is substantially box-like and encloses an inner volume 14 of the warehouse 10. In Figures 1 and 2, parts of the walls 13 placed in the front and rear position have been removed to show part of the inner volume 14 of the warehouse 10. In Figure 3 and 4 the walls 13 have not been represented.

[0135] The warehouse 10 is a structurally independent structure located within a formation plant. In other words, the warehouse 10 is a cabinet. A plurality of warehouses 10 may be provided within a formation plant.

[0136] The containment structure 12 is arranged to be mounted or rested on a floor of a warehouse or the like of an electrochemical cell formation plant.

[0137] The warehouse 10 comprises at least one formation station 15. In the preferred embodiment of the invention, the warehouse 10 comprises a plurality of formation stations 15. The formation stations 15 are physical positions within the warehouse 10 at which the electrochemical cells 100 are subjected to the formation process. The formation stations 15 are arranged one on top of the other to form columns of formation stations 15. By way of example, four columns of formation stations 15 may be provided. Each formation station 15 is closed to the outside of the warehouse 10 by the walls 13. Each formation station 15 is open towards the inner volume 14. Between the columns of formation stations 15, in the inner volume 14, there is provided a space not occupied by the formation stations 15.

[0138] The warehouse 10 comprises a plurality of formation modules 16. Figure 6 schematically represents a formation module 16.

[0139] Each formation module 16 has the function of at least partially forming the electrochemical cells 100 present in a cell tray 1 1. For this purpose, each formation module 16 is configured to supply electrical energy and preferably receive electrical energy from the electrochemical cells 100 in accordance with a formation recipe that establishes times, voltages, current intensities that the formation module 16 must supply and receive from the electrochemical cells 100.

[0140] Each formation module 16 comprises a contacting assembly 17 (schematized in Figures 6 and 7) configured to contact electrical poles of the electrochemical cells 100 placed in a cell tray 1 1 . The contacting assembly 17 comprises a plurality of electrical contacts 17a configured to enter into electrical contact relationship with poles of the electrochemical cells 100.

[0141] Each formation module 16 further comprises at least one bi-directional converter 18 (schematized in Figure 7) which is placed in electrical connection with the contacting assembly 17. Each bi-directional converter is configured to deliver in output the voltage and current necessary to implement the formation recipe. Preferably, the bi-directional converter 18 is the last stage of a current conversion which, starting from a current, for example alternating, supplied at the plant level, supplies a current with voltage and intensity directly deliverable to the electrochemical cells. By way of example, the bi-directional converter 18 can be a bi-directional DC / DC power supply, which for example receives an input current with a voltage comprised between 12 Volts and 48 Volts and delivers a current with a voltage comprised between 2 and 8 Volts, for example of about 4.2 Volts. By way of example, each bi-directional converter 18 may be sized to deliver a maximum current substantially comprised between 0.05 C and 0.4 C, where C indicates a current value expressed in Amperes numerically equal to the capacity in Ah of an electrochemical cell 100. The number of bi-directional converters 18 of each formation module 16 depends on the number of electrochemical cells 100 which must be formed by the formation module 16 and on the electrical sizing of the bi-directional converter 18. Preferably a plurality of bi-directional converters 18 is provided for each formation module 16. For example, a bi-directional converter 18 may be provided for each electrochemical cell 100 of a cell tray 1 1 . Each formation module 16 may further comprise at least one control unit 19 (only schematized in Figure 7), for example a microprocessor unit, configured to command the operation of the plurality of bi-directional converters 18 so as to generate for each electrochemical cell a respective voltage or modulated current, suitable for operating the formation process.

[0142] Each formation module 16 comprises a containment frame 16a containing and integrating the bi-directional converters 18, the contacting assembly 17 and possibly the control unit 19. The contacting assembly 17 is not movable with respect to the bi-directional converters 18.

[0143] A plurality of drawers 20 are also provided within the warehouse 10. Each drawer 20 defines a supporting structure or frame 21 (schematized in Figure 5). The drawers 20 are substantially identical to each other and may have a box-like shape, a substantially planar shape or any other shape. Each drawer 20 is sized to engage and occupy a formation station 15. As schematically illustrated in Figure 5, a plurality of formation modules 16 are mounted on each drawer 20, preferably arranged one next to the other to define a row of formation modules 16. Also shown in Figure 5 are cell trays 1 1 associated with the contacting assemblies 17 of the formation modules 16. Each drawer 20 thus defines a supporting structure or frame 21 for the formation modules 16 mounted thereon. Each drawer 20 with the relative formation modules 16 mounted thereon is placed inside a respective formation station 15, as schematically illustrated in Figure 4.

[0144] To supply with electrical power the formation modules 16, and in particular the bidirectional converters 18, the warehouse 10 comprises a power supply unit 22. The power supply unit 22 comprises a plurality of electrical converters23, preferably of the bi-directional type, each configured to change input voltage values from an electrical power source 24 external to the warehouse 10 to usable input voltage values to the bi-directional converters 18 of the formation modules 16. The electrical converters 23 can be AC / DC or DC / DC converters or both types depending on the electrical conversion diagram to be implemented. The electrical converters 23 can be placed, alternatively or in combination, in appropriate electrical cabinets of the warehouse 10, in each drawer 20, in each formation module 16. In Figure 7 an electrical converter 23 placed in a drawer 20 has been schematized.

[0145] In any case, in each formation station 15 there is provided at least one electrical quick-coupling connector 25 placed in electrical connection with the external electrical power source 24. Each drawer 20 comprises at least one electrical plug

[0146] 26 configured to electrically connect with the electrical quick-coupling connector 25. The electrical plug 26 places the electrical quick-coupling connector 25 in electrical connection with the bi-directional converters 18 of the formation modules 16 placed on the drawer 20. The electrical converters 23, depending on the placement position chosen, can be placed upstream of the electrical plug 26 or downstream of the electrical plug 26 (as in the example illustrated in Figure 7).

[0147] As schematically illustrated in Figure 1 , the warehouse 10 comprises at least one service station 27 located at a maintenance level below the formation stations 15. The service station 27 is placed at a maintenance level that is directly reachable by maintenance operators. The service station 27 is open both towards the inner volume 14 of the warehouse 10 and towards the external environment. On the side facing the external environment, the service station 27 comprises an opening 28 directly accessible from the external environment. At the opening 28 there is provided a gate 29 configured to close in a controlled manner the opening 28 and inhibit access to the service station 27. Figure 1 schematically shows the gate 29 in open condition.

[0148] The drawers 20 are movable within the warehouse 10 to be able to be moved between the respective formation stations 15 and the service station 27, so that each drawer 20 can carry the formation modules 16 mounted thereon in the service station 27 to be able to perform maintenance operations on the formation modules 16.

[0149] In this regard, the warehouse 10 comprises a transport system 30 configured to transport one drawer 20 at a time between the respective formation station 15 and the service station 27 and between the service station 27 and the respective formation station 15. The transport system 30 is placed inside the warehouse 10, in the inner volume 14. Preferably, the transport system 30 is placed in a space between the columns of formation stations 15.

[0150] The transport system 30 is configured to pick up each drawer 20 from the respective formation station 15 and to insert the drawer 20 into the service station

[0151] 27 and to pick up a drawer 20 from the service station 27 and insert it into the respective formation station 15.

[0152] The transport system 30 comprises a lift 31 schematized in Figure 3. The lift 31 comprises a resting structure 36 that picks up and supports a drawer 20 during its movement inside the warehouse 10. In the preferred embodiment of the invention, the resting place 36 has sizes substantially equal to the sizes of a drawer 20. The lift 31 is connected to vertical guides 32 that develop vertically inside the warehouse 10 and reach in height all the formation stations 15. The vertical guides 32 develop at least starting from the service station 27. The vertical guides 32 define a vertical transport path for the lift 31 and are placed in the space between the columns of formation stations 15, so that the lift 31 transporting a respective drawer 20 can move within the warehouse 10 without interfering with the formation stations 15. In some embodiments in which there are a plurality of columns of formation stations 15 arranged side by side inside the warehouse 10, the resting structure 36 can slide horizontally along a horizontal guide 33. The horizontal guide 33 develops between the vertical guides 32. The lift 31 can reach any drawer 20 placed in any formation station 15. The resting structure 36, when the lift 31 is positioned at a drawer 20, picks up and supports said drawer 20. Figure 3 schematically illustrates the lift 31 which has just brought a drawer 20 from a formation station 15 (illustrated empty in Figure 3) to the service station 27.

[0153] As schematically illustrated in Figure 2, the warehouse 10 comprises a transfer station 34 to which the cell trays 1 1 containing the electrochemical cells 100 that must be subjected to the formation process are conferred, preferably one at a time. The transfer station 34 is intended to allow the entry and exit of cell trays 1 1 from the warehouse 10. The transfer station 34, when the warehouse is in use to perform formation processes, is preferably the only access through which the cell trays 1 1 can be introduced and extracted from the warehouse 10.

[0154] The transfer station 34 comprises an opening 35 to allow the cell trays 1 1 to enter the inner volume 14 of the containment structure 12 and to exit the inner volume 14 of the containment structure 12. The transfer station 34 is located in a lower portion of the warehouse 10 at a transport level that is elevated with respect to the floor level (i.e. the level at which the floor of a plant in which the warehouse 10 is mounted is located). As schematically illustrated in Figure 2, the warehouse 10 comprises a single transfer station 34.

[0155] The transfer station 34 is located on a side wall of the warehouse other than the side wall on which the service station 27 is placed. Preferably, the transfer station 34 and the service station 27 are placed on mutually opposite side walls of the warehouse 10. To allow the transport of trays 1 1 inside the warehouse 10 and their positioning in the formation stations 15, the transport system 30 is also configured to transport the cell trays 1 1 inside warehouse 10 between the formation stations 15 and the transfer station 34.

[0156] In this regard, the lift 31 comprises a platform 37 configured and sized to support and transport a cell tray 1 1 . The platform 37 is slidable in a horizontal direction along the lift 31. The lift 31 is selectively configurable between a drawer 20 transport condition and a tray 1 1 transport condition. The platform 37 is slidably mounted in a horizontal direction on the resting structure 36. The platform 37 can be lifted in height with respect to the resting structure 36 and can be inserted into the resting structure 36. When the platform 37 is inserted into the resting structure 36, the lift 31 is in a drawer 20 transport condition. When the platform is placed elevated with respect to the resting structure 36, the lift is in a tray 1 1 transport condition. In the preferred embodiment of the invention, the platform 37 has sizes substantially equal to the sizes of a cell tray 1 1 . Figure 4 illustrates the transport system 30 in which the lift 31 is in the cell tray 1 1 transport condition.

[0157] As schematized in Figure 9, the warehouse 10 comprises a thermal conditioning system 40. The thermal conditioning system 40 is preferably a liquid conditioning system, wherein a conditioning liquid is heated or cooled to act as a heating or cooling agent. Such conditioning liquid may for example be demineralised, osmotised or distilled water. The thermal conditioning system 40 has the function of thermally conditioning at least the electrochemical cells 100 during the formation process, in such a way as to place the electrochemical cells 100 at predetermined and controlled temperatures.

[0158] The thermal conditioning system 40 comprises a warehouse conditioning circuit 41 . The thermal conditioning system 40 further comprises a fluid conditioner 42.

[0159] In the embodiment illustrated in Figure 9, the fluid conditioner 42 has been illustrated positioned within the warehouse 10. In other embodiments, the fluid conditioner 42 may be external to the warehouse 10. The fluid conditioner 42 may be any device capable of bringing the conditioning liquid of the thermal conditioning system 40 to a predetermined temperature, for example capable of cooling the conditioning liquid.

[0160] The warehouse conditioning circuit 41 has the function of bringing conditioning liquid at each formation station 15. For this purpose, the warehouse conditioning circuit 41 comprises a group of delivery hydraulic pipings 43 connecting the fluid conditioner 42 with each formation station 15 and a group of return hydraulic pipings 44 connecting each formation station 15 with the fluid conditioner 42, as schematized in Figure 9.

[0161] The warehouse conditioning circuit 41 further comprises delivery hydraulic connectors 45 and return hydraulic connectors 46 placed at each formation station 15. The delivery hydraulic connectors 45 and the return hydraulic connectors 46 are placed respectively on the group of delivery hydraulic pipings 43 and on the group of return hydraulic pipings 44. The delivery hydraulic connectors 45 and the return hydraulic connectors 46 are quick-coupling connectors, i.e. hydraulic connectors that can be connected to further hydraulic connectors and disconnected from said further hydraulic connectors without the need to use clamping tools. In each formation station 15 a plurality of delivery hydraulic connectors 45 and return hydraulic connectors 46 are provided, preferably in number equal to the number of formation modules 16 present in a drawer 20. Note that the transfer station 34 is not served by the thermal conditioning system 40. The service station 27 may, in some embodiments, be served by the thermal conditioning system 40 and comprise respective delivery hydraulic connectors 45 and return hydraulic connectors 46.

[0162] As schematized in Figure 10, each cell tray 1 1 comprises a tray conditioning circuit 47. The tray conditioning circuit 47 is preferably integrated into the cell tray 11 . The tray conditioning circuit 47 may for example comprise a heat exchanger. The tray conditioning circuit 47 comprises a delivery hydraulic connector 48 and a return hydraulic connector 49. The delivery hydraulic connector 48 is configured to hydraulically connect with one of the delivery hydraulic connectors 45 of the group of delivery hydraulic pipings 43. The delivery hydraulic connectors 48 and the return hydraulic connectors 49 are quick-coupling connectors.

[0163] The thermal conditioning system 40 may also be active on the formation modules 16 placed in the drawers 20 to thermally condition (usually to cool) the formation modules 16 when in use.

[0164] In this regard, as schematically illustrated in Figure 6, each formation module 16 comprises a formation module conditioning circuit 50. The formation module conditioning circuit 50 is preferably integrated into the formation module 16. The formation module conditioning circuit 50 may for example comprise a heat exchanger. The formation module conditioning circuit 50 comprises a delivery hydraulic connector 51 and a return hydraulic connector 52. The delivery hydraulic connector 51 is configured to connect hydraulically with the return hydraulic connector of the tray conditioning circuit 47. The return hydraulic connector 52 is configured to hydraulically connect with one of the return hydraulic connectors 46 of the group of return hydraulic pipings 44. The delivery hydraulic connectors 51 and the return hydraulic connectors 52 are quickcoupling connectors.

[0165] In use, to implement a method for at least partial forming electrochemical cells, a cell tray 1 1 reaches the transfer station 34 where it is picked up by the transport system 30. During this operation, the lift 31 is configured in the cell tray 1 1 transport condition. The cell tray 1 1 is brought at a formation station 15 by moving inside the warehouse 10, in particular by moving in the inner volume 14 transported by the platform 37 of the lift 31. When the cell tray 1 1 reaches the chosen formation station 15, the cell tray 1 1 is inserted into the respective drawer 20. In the preferred embodiment of the invention, the cell tray 1 1 is inserted into the formation station 15 directly from the platform 37. During this operation, the cell tray 1 1 is coupled to a formation module 16 present in the drawer 20. As schematically depicted in Figure 4, each formation module 16 is configured to couple with a respective cell tray 1 1 . In particular, the electrochemical cells contained in the cell tray 1 1 are contacted by the contacting assembly 17 of the formation module 16. In this way the bi-directional converters 18 are in electrical contact with the electrochemical cells 100 to be formed. In each formation station 15 only one drawer 20 is provided.

[0166] In this condition, the formation modules 16 are electrically connected to the external electrical power source 24. In particular, the electrical plug 26 of the drawer 20 is connected to the electrical quick-coupling connector 25 of the formation station 15.

[0167] When the cell tray 1 1 is coupled to the formation module 16, the tray conditioning circuit 47 is hydraulically connected to the warehouse conditioning circuit 41 through one of the delivery hydraulic connectors 45 of the group of delivery hydraulic pipings 43. The tray conditioning circuit 47 is also connected to the formation module conditioning circuit 50.

[0168] The formation module 16 is then activated and the electrochemical cells 100 are subjected to the formation process. During the formation process, conditioning liquid is sent to the tray conditioning circuit 47 and therefrom to the formation module conditioning circuit 50.

[0169] At the end of the formation process, or in any case upon partial completion of the formation process (if necessary to implement a particular formation recipe), the cell tray 1 1 comes from the formation station 15. During this operation, the cell tray 1 1 is decoupled from the formation module 16 present in the drawer 20. The contacting assembly 17 of the formation module 16 is disconnected from the electrochemical cells 100 of the cell tray 1 1 . This operation is preferably carried out by the platform 37 of the lift 31 . During the extraction of the cell tray 1 1 from the formation station 15, the tray conditioning circuit 47 is hydraulically disconnected from the warehouse conditioning circuit 41 and the formation module conditioning circuit 50.

[0170] The transport system 30 carries the cell tray 1 1 at the transfer station 34. This operation is carried out by the lift 31 configured in the cell tray 1 1 transport condition which supports and transports the cell tray 1 1 in the inner volume 14. When the cell tray 1 1 reaches the transfer station 34, the cell tray 1 1 is picked up by the platform 37 of the lift 31 and extracted from the warehouse 10.

[0171] In the event that it is necessary to carry out maintenance operations on a formation module 16 or on all the formation modules 16 of the same drawer 20, it is provided to bring the drawer 20 containing the formation module 16 to be maintained in the service station 27.

[0172] This operation can be carried out both in the event that some or all of the formation modules 16 of the drawer 20 are associated with cell trays 1 1 , and in the event that no formation module 16 of the drawer is associated with a cell tray 11 . The first case may for example happen when an unexpected event occurs, such as for example a thermal runaway of the electrochemical cells 100 of a cell tray 1 1 being formed. The second case may for example occur during a scheduled maintenance of the formation modules 16.

[0173] In the first case, it is provided to hydraulically disconnect the tray conditioning circuit 47 of each cell tray 1 1 present in the drawer 20 from the warehouse conditioning circuit 41. It is also provided to hydraulically disconnect all the formation module conditioning circuits 50 of the formation modules 16 placed in the drawer 20 from the warehouse conditioning circuit 41 .

[0174] In the second case it is provided to hydraulically disconnect all the formation module conditioning circuits 50 of the formation modules 16 placed in the drawer 20 from the warehouse conditioning circuit 41 .

[0175] In both cases it is also provided to electrically disconnect the formation modules 16 of the drawer 20 from the external electrical power source 24. This operation is carried out by disconnecting the electrical plug 26 from the electrical quickcoupling connector 25 of the formation station 15. Note that no formation module 16 of a further drawer 20 needs to be electrically disconnected from the external electrical power source 24. Thus, any formation process being executed by any formation module 16 placed on a different drawer 20 may continue without being interrupted.

[0176] At this point, the transport system 30 positions the lift 31 at the formation station 15 and picks up the drawer 20 with the relative formation modules 16 mounted thereon. In this step, the lift 31 is configured in the drawer 20 transport condition. The transport system 30 moves the lift 31 with the drawer 20 at the service station 27. At this point, the transport system 30 positions the drawer in the service station 27. An electrical quick-coupling connector 25 identical to those provided in the formation stations 15 is provided in the service station 27. If necessary, the electrical plug 26 can be connected to the quick-connect electrical connector 25 of the service station 27.

[0177] The formation modules 16 mounted on the drawer 20 can be subjected to maintenance operations. This operation can be carried out without interrupting any formation process being executed by any formation module 16 placed on a drawer 20 inserted in any formation station 15.

[0178] At the end of the maintenance, the transport system 30 picks up, through the lift 31 , the drawer 20 and the formation modules 16 mounted therein from the service station 27. At this point, the transport system 30 positions the lift 31 at the formation station 15 from which the drawer 20 had been picked up. The transport system 30 then positions the drawer 20 in the formation station 15. During the positioning of the drawer 20 in the formation station 15 it is provided to electrically connect the formation modules 16 of the drawer 20 to the external electrical power source 24. This operation is carried out by connecting the electrical plug 26 to the electrical quick-coupling connector 25 of the formation station 15. During the positioning of the drawer 20 in the formation station 15 it is provided to hydraulically connect all the formation module conditioning circuits 50 of the formation modules 16 placed in the drawer 20 to the warehouse conditioning circuit 41 . The formation modules 16 are thus ready to receive tray drawers 11 and implement formation processes on the electrochemical cells 100.

Claims

CLAIMS1 . Warehouse (10) for the formation of electrochemical cells (100), comprising a containment structure (12) within which are housed: a plurality of formation modules (16), a plurality of drawers (20), a plurality of formation stations (15) and at least one service station (27); wherein each formation module (16) is configured to be coupled to a cell tray (1 1 ) to implement an at least partial formation cycle of electrochemical cells (100) contained in said cell tray (1 1 ); wherein at least part of at least one formation module (16) of said plurality of formation modules (16) is placed in each drawer (20), of at least one group of drawers of said plurality of drawers (20); wherein each drawer (20) of said at least one group of drawers (20) is movable within said containment structure (12) between said at least one formation station (15) of said plurality of formation stations (15) and said at least one service station (27).

2. Warehouse (10) according to claim 1 , wherein said service station (27) comprises an opening (28) to expose a drawer (20) of said at least one group of drawers, when placed in the service station (27), to an environment external to an inner volume (14) of said containment structure (12).

3. Warehouse (10) according to claim 1 or 2, wherein within said containment structure (12), a transport system (30) is housed for transferring each drawer (20) of said at least one group of drawers between a respective formation station (15) and said service station (27) and between said service station (27) and said respective formation station (15).

4. Warehouse (10) according to any one of the preceding claims, wherein each drawer (20) of said at least one group of drawers is movable within said containment structure (12) independently of any other drawer (20) of said at least one group of drawers.

5. Warehouse (10) according to any one of the preceding claims, wherein the formation stations (15) of said plurality of formation stations are placed above said service station (27).

6. Warehouse (10) according to any one of the preceding claims, wherein eachformation module (16) comprises a contacting assembly (17) configured to provide an electrical contact for each of said electrochemical cells (100) housed in a cell tray (1 1 ) and at least one bi-directional converter (18) in electrical connection with said contacting assembly (17); at least one formation module (16) being placed in each drawer (20) of said group of drawers.

7. Warehouse (10) according to claim 6, wherein each bi-directional converter (18) of a formation module (16) is placed in electrical connection with an electrical source (24) when the respective drawer (20) is in a respective formation station (15) and wherein each bi-directional converter (18) of a formation module (16) is disconnected from said electrical source (24) when the respective drawer (20) is moved between the respective formation station (15) and the service station (27) and between the service station (27) and the respective formation station (15).

8. Warehouse (10) according to claim 7, wherein at least one electrical quickcoupling connector (25) is placed in each formation station (15) to put said electrical source (24) in electrical connection with each bi-directional converter (18) of the formation modules (16) placed in a drawer (20) of said group of drawers.

9. Warehouse (10) according to claim 7 or 8, wherein at least one electrical quick-coupling connector (25) is placed in said service station (27), configured to put said electrical source (24) in electrical connection with each bi-directional converter (18) of the formation modules (16) placed in a drawer (20) when said drawer is placed in the service station (27).

10. Warehouse (10) according to any one of the preceding claims, comprising at least one transfer station (34) configured to interface between an inner volume (14) of said containment structure (12) and an environment external to said inner volume (14) of said containment structure (12) and to receive cell trays (1 1 ) from said external environment and to deliver cell trays (1 1 ) from said inner volume (14) to said external environment.11 . Warehouse (10) according to claim 10, wherein said service station (27) is placed along a wall of said warehouse other than a wall along which said transfer station (34) is placed.

12. Warehouse (10) according to claims 3 and 10, wherein said transportsystem (30) is further configured to transfer cell trays (1 1 ) containing electrochemical cells (100) inside said containment structure (12) between said transfer station (34) and drawers (20) placed in the formation stations (15) and between said drawers (20) placed in the formation stations (15) and said transfer station (34).

13. Method for at least partially forming electrochemical cells comprising: providing a warehouse (10) according to one or more of claims 1 to 12; coupling a cell tray (11 ) containing electrochemical cells (100) to a formation module (16) placed in a drawer (20) inserted in a formation station (15); actuating at least a partial formation cycle of the electrochemical cells (100); if maintenance operations must be carried out on the formation module (16), it is provided for: moving the drawer (20) from the formation station (15) to the service station (27); carrying out maintenance operations on said formation module (27) when the drawer (20) is placed in the service station (27); at the end of the maintenance operations, moving the drawer (20) from the service station to the formation station (15).

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