Store for the formation of electrochemical cells for battery production

Abstract

A store (10) for the formation of electrochemical cells (1) for battery production, in which a plurality of formation chambers (15) is defined and comprises a plurality of drawers (20), removably housed in one of the formation chambers (15). Each drawer (20) comprises a plurality of housings (21), to accommodate a respective tray (11) containing the electrochemical cells (1), a plurality of formation modules (22) and a power supply unit (23). Each formation module (22) comprises a contacting assembly (24) which provides an electrical contact for each electrochemical cell (1) contained in the tray (11) accommodated in a housing (21), at least one bidirectional electrical converter (25) connected to the contacting assembly (24) and an electronic control unit (26) to apply to the electrochemical cells (1), by means of the contacting assembly (24) and the at least one bidirectional electrical converter (25), a modulated voltage or current such as to allow the at least partial formation of said electrochemical cells (1).

Description

[0001] Store for the formation of electrochemical cells for battery production

[0002] The present invention relates to a store specifically designed for the formation of electrochemical cells within a battery production process.

[0003] The present invention finds preferred, though not exclusive, application in the production of secondary batteries, e.g. lithium-ion batteries, which will be referred to below without loss of generality.

[0004] As is well known, the production of electrochemical cells includes, in its most general terms:

[0005] - a step of mechanically constructing the electrochemical cell, wherein a winding of electrodes of a predefined shape and size is made, and wherein this winding is inserted into a protective outer casing,

[0006] - a step of filling the electrochemical cell with an electrolyte solution, and finally,

[0007] - a step of forming the electrochemical cell to make it suitable for supplying and / or storing electrical energy.

[0008] In particular, the latter step involves one or more electrochemical cell charge and discharge operations through the administration of modulated voltages or currents, thanks to which electrochemical phenomena are induced within the electrochemical cell, leading to the formation of a solid electrolyte interface at the electrodes.

[0009] The formation of such an interface is essential to define and optimise the properties of the electrochemical cell in terms of both charge capacity and uniformity of successive charge and discharge cycles.

[0010] In a known procedure, the electrochemical cells to be subjected to the formation process are placed in a tray provided with special housings that allow them to be transported all together in a predefined orientation and position.

[0011] The tray generally has no lid so that the electrochemical cells are freely accessible from above.

[0012] The tray with the electrochemical cells is then taken to a formation store with several formation chambers where it is contacted by a special apparatus that supplies (or draws from) each electrochemical cell with a voltage or current modulated according to a predefined electrical charge and discharge pattern.

[0013] For this purpose, the apparatus comprises a contacting assembly, configured to make electrical contact with each electrochemical cell, and typically mounted on a frame with the ability to move vertically so that it can be lowered onto the tray and make contact with the electrochemical cells housed therein.

[0014] Typically, the contacting assembly of the apparatus is powered by a plurality of bi-directional electrical converters controlled by a control unit that defines the timing and manner of the charge and discharge phases of the individual electrochemical cells in the tray.

[0015] In turn, bidirectional electrical converters are connected to a power supply unit that converts an incoming electrical current, e.g. a 380 Volt alternating current, into an outgoing electrical current, e.g. a 12 Volt direct current.

[0016] In this way, charge and discharge cycles of the electrochemical cells can be carried out, at the completion of which the contacting assembly is lifted from the electrochemical cells, allowing the entire tray containing them to be moved to a subsequent work station, typically an aging station, as better explained below.

[0017] In the present disclosure as well as in the herein enclosed claims, certain terms and expressions are deemed to have, unless otherwise expressly indicated, the meaning expressed in the following definitions.

[0018] A “store” means a containment structure, preferably of the stand-alone type, suitable for positioning within a battery production plant, equipped with a frame, possibly enclosed by one or more outer walls, within which a plurality of chambers is obtained in which the trays containing the electrochemical cells can be housed.

[0019] Preferably, the store frame consists of a metal structure comprising a plurality of vertical uprights and interconnected horizontal beams or shelves.

[0020] In the industry, the store is also called a “rack”.

[0021] The “formation chamber” of a store is understood to be a defined location within a formation store and arranged to house a plurality of electrochemical cells, preferably contained in one or more trays, and in which these electrochemical cells can be subjected to a formation process. / formation chamber is preferably configured to house a “drawer” inside it, defined as an element prepared to be positioned in a store formation chamber and movable with respect to the formation chamber.

[0022] A drawer is preferably configured to accommodate and support a plurality of trays in order to keep them in a desired position within the formation chamber during the electrochemical cell formation step.

[0023] In other words, a drawer is basically shaped like a container, which is engaged in a removable manner with the store frame, e.g. by sliding, so that it can be accommodated within a formation chamber or, if necessary, removed from the formation chamber to be transported to another position in the store.

[0024] A formation chamber can be defined by a shelf on which a drawer rests, or by a supporting element, such as guides that can engage and hold the drawer in a certain position within the store.

[0025] The “consolidation” process of an electrochemical cell refers to the set of operations to which an electrochemical cell is subjected in order to form a solid electrolyte interface at at least one of its electrodes.

[0026] These operations generally comprise a “formation” step during which the electrochemical cell is subjected to one or more electric charge and subsequent electric discharge cycles, possibly alternating with rest cycles.

[0027] The formation step is usually followed by a “maturation” step (more commonly known by the term “aging”) during which the electrochemical cell is left to rest for an appropriately long time, so as to allow completion of the above-mentioned solid electrolyte interface.

[0028] The formation and aging steps may be distinct and separate, carried out one after the other, but in some types of processes they may be interspersed with each other, e.g. having a first formation step followed by a first aging step followed by a second formation step and a second aging step.

[0029] In the relevant technical field, the term “formation” is sometimes used to identify the entire consolidation process of the electrochemical cell, while the formation step is sometimes called the “activation” step.

[0030] “Formation module” means a group of electrical components capable of implementing the electrical charge and discharge cycles of the electrochemical cells contained in a tray.

[0031] The formation module is sometimes called a “power module” or “power device”.

[0032] Two or more components form an “individually manipulable unit” when they are bound together so that they can be transported, held, supported as if they were a single component.

[0033] The components of an individually manipulable unit can be bound together in a removable manner so that, if necessary, these components can be separated and form separate units.

[0034] The Applicant preliminarily noted that the electrochemical cell consolidation process represents a particularly critical step within the battery production cycle, due to the very long time required in both the formation and the subsequent aging step. The formation step can last as long as 10 to 15 hours while the aging step normally lasts several days, e.g. 10 to 12 days.

[0035] The Applicant thus verified that in an industrial battery production process, in which several thousand electrochemical cells per hour can be packed, enormous space is required to store the electrochemical cells for the time needed for their consolidation process.

[0036] The Applicant therefore realised that an improved consolidation process in terms of time and layout would have a major positive impact on the entire production cycle.

[0037] In this perspective, the Applicant noted that the electrochemical cell formation step appeared particularly cumbersome and time consuming.

[0038] In particular, the Applicant noted that the contacting assemblies used to contact the electrochemical cells in the tray and subject them to the envisaged charge and discharge cycles are connected to the respective bidirectional electrical converters and to the power supply unit by means of a complex system of electrical cables which, in total, occupy a large part of the store structure.

[0039] Moreover, the Applicant verified that such a system of electrical cables not only reduced the space available for the electrochemical cell tray formation process, but also constituted a significant cost in setting up the infrastructure of the formation store. The Applicant therefore noted that in conventional stores, both the bidirectional electrical converters with their respective control units and the power supply units are located in dedicated housings of the store, separate and distinct from the formation chambers.

[0040] On the basis of these observations, the Applicant therefore realised that by moving all the electrical components necessary to conduct the electrochemical cell formation process close to the seats where the trays containing the cells to be formed are housed, the need to use a large part of the electrical connection cables would be dispensed with, thereby appreciably simplifying the layout of the store and increasing the space available for the accommodation of electrochemical cells.

[0041] Furthermore, the Applicant realised that the layout and performance of the formation store could be further optimised by integrating the necessary components for the simultaneous formation of several trays of electrochemical cells in a single mobile unit.

[0042] The Applicant finally found that a store for the formation of electrochemical cells, comprising a plurality of drawers removably housed in a respective formation chamber, wherein each drawer comprises, together with a plurality of housings configured to accommodate respective electrochemical cell trays, also the electrical components used to conduct the formation process of the electrochemical cells contained in the trays, allowed for a tremendous reduction in the amount of electrical wiring present within the store, optimisation of the internal space and improved management of the electrical components.

[0043] In fact, each drawer forms an individually manipulable unit, which can be easily disconnected from the main utilities of the store (e.g. from the power supply and possibly from a thermal conditioning circuit) and just as easily transported out of the formation chamber. In this way, it is possible to move all components for the same plurality of trays to a desired location, e.g. in a maintenance station, in one step.

[0044] Furthermore, the proximity between power supply units, bidirectional electrical converters and contacting assemblies means that the cables required for connections between the different components can be minimised.

[0045] In a first aspect thereof, therefore, the present solution is directed at a store for the formation of electrochemical cells for battery production. Preferably, a plurality of formation chambers is defined in the store.

[0046] Preferably, the store comprises a plurality of drawers.

[0047] Preferably, each drawer is housed, more preferably in a removable manner, in one of said formation chambers.

[0048] Preferably, each drawer comprises a plurality of housings.

[0049] Preferably, each housing is configured to accommodate a respective tray containing said electrochemical cells.

[0050] Preferably, each drawer comprises a plurality of formation modules.

[0051] Preferably, each formation module comprises a contacting assembly configured to provide an electrical contact for each electrochemical cell contained in said tray when accommodated in one of said housings.

[0052] Preferably, each formation module comprises at least one bidirectional electrical converter connected to said contacting assembly to supply and receive electrical current to and from said electrochemical cells.

[0053] Preferably, each formation module comprises at least one electronic control unit configured to apply to said electrochemical cells, by means of said contacting assembly and said at least one bidirectional electrical converter, a modulated voltage or current such as to allow the at least partial formation of said electrochemical cells.

[0054] Preferably, each drawer comprises a power supply unit connected to each formation module.

[0055] Preferably, each power supply unit is configured to transform an incoming electric current, having a first voltage, into an outgoing electric current, having a second voltage adapted to supply said formation modules.

[0056] Preferably, said second voltage is lower than said first voltage.

[0057] Thanks to these characteristics, the store for the formation of electrochemical cells proposed by the present solution has an optimised and more economical layout, largely due to the reduction of electrical cables, and allows for greater flexibility and speed in the handling of electrical components. The present solution, in the aforementioned aspect, may have at least one of the further preferred features set forth below.

[0058] In some embodiments, the contacting assembly comprises two electrical contacts for each electrochemical cell contained in said tray. Preferably, these electrical contacts are arranged to directly contact the anode and cathode of an electrochemical cell, respectively.

[0059] In other embodiments, the contacting assembly has at least one contact configured to be electrically connected to the anode or cathode of an electrochemical cell without direct contact, e.g. by means of a conductive track associated with the tray.

[0060] In some embodiments, said formation module comprises at least one bidirectional electrical converter, also known simply as a bidirectional power supply, for each electrochemical cell.

[0061] The at least bidirectional electrical converter is preferably configured to transform a direct current input having a voltage comprised between 12 and 48 volts into a direct current output having a voltage comprised between 0 and 6 volts and vice versa.

[0062] Preferably, the input current to at least one bidirectional electrical converter is a direct current with a voltage comprised between 12 and 48 Volts.

[0063] Preferably, said at least one bidirectional electrical converter is mounted on an electronic board.

[0064] Preferably, the electronic control unit of said at least one bidirectional electrical converter is also mounted on the same electronic board.

[0065] In some embodiments, each electronic control unit is associated with four bidirectional electrical converters, and, preferably, said electronic control unit and said four bidirectional electrical converters are mounted on the same electronic board.

[0066] In some embodiments, said contacting unit, said at least one electronic control unit and said at least one bidirectional electrical converter are integrated with each other in said formation module.

[0067] In other words, said formation module forms an individually manipulable unit where the aforementioned components are solidly coupled together.

[0068] In some embodiments, said power supply unit comprises one or more electrical converters, preferably bidirectional, capable of transforming an input current into an output current adapted to be supplied to the bidirectional electrical converter of a formation module, e.g. into a direct current with a voltage between 12 and 48 volts and vice versa.

[0069] In an embodiment, the input current is an alternating current, preferably with a voltage comprised between 200 and 400 volts.

[0070] In an alternative embodiment, the input current is a direct current, preferably with a voltage comprised between 600 and 800 volts.

[0071] In some embodiments, each electrical converter of said power supply unit is connected to each formation module of said drawer.

[0072] In some embodiments, each formation module is associated with a respective housing defined in said drawer.

[0073] In some embodiments, each formation module is movable with respect to said tray between an operational position, wherein said contacting assembly is moved towards a tray received in said housing, and a non-operational position wherein said contacting assembly is distanced from said tray.

[0074] Preferably, each drawer comprises a movement member associated with each formation module for moving the formation module between said operational position and said non-operational position.

[0075] In other words, each formation module is moved by a respective movement member.

[0076] Preferably, said movement member moves said formation module from said non- operational position to said operational position by lifting it upwards.

[0077] In this way, the electrochemical cells contained in the tray are contacted by the formation module from below.

[0078] In other embodiments, it is envisaged that the movement member moves the formation module from said non-operational position to said operational position by lowering it downwards. In other embodiments, the drawer comprises a movement member associated with each housing and configured to move the tray in said housing towards and away from the respective formation module.

[0079] Preferably, each formation module can be moved between said non-operational position and said operational position independently of the other formation modules.

[0080] In this way, it is possible to optimise the time required for the formation process for the electrochemical cells in each tray, without being constrained by the presence or absence of trays in the other housings of the drawer.

[0081] In some embodiments, said power supply unit remains integral with said drawer whereas said formation module is moved between said non-operational and said operational position.

[0082] In other words, the power supply unit is connected to each formation module in such a way that there is limited movement of the formation module with respect to the power supply unit.

[0083] In some embodiments, said formation store is closed by outer walls and comprises an opening for the entry and / or exit of said trays.

[0084] In this way, all the components on the drawers housed in the various formation chambers are better protected and the environment within the store more easily controllable.

[0085] In some embodiments, a transfer station configured to receive said trays at the entrance to said store is defined.

[0086] In some embodiments, said formation store comprises an internal transport system, configured to transport said tray from said entrance, preferably from said transfer station, to one of said housings.

[0087] In some embodiments, said formation chamber comprises an internal transport system, configured to move said drawer towards and away from said formation chamber.

[0088] Preferably, there is a single said internal transport system. In other words, the same internal transport system is used, when necessary, to move both the trays and the drawers. In some embodiments, said drawers are housed in formation chambers that are in columns inside the store.

[0089] Preferably, said formation chambers are arranged in at least two separate columns and said transport system is movable between at least two of said columns of formation chambers.

[0090] In some embodiments, a removable electrical connection is provided at each formation chamber to connect said power supply unit to an electric power source.

[0091] In some embodiments, said formation store comprises a maintenance station. Preferably, said drawer can be moved from said formation chamber to said maintenance station.

[0092] The features and advantages of the present solution will become clearer from the detailed description of an embodiment shown, by way of non-limiting example, with reference to the appended drawings in which:

[0093] - Figure 1 is a schematic front perspective view of a store for the formation of electrochemical cells made in accordance with the present solution, with one wall partially removed;

[0094] - Figure 2 is a schematic perspective view from the rear of the store in Figure 1 with a partially removed wall;

[0095] - Figure 3 is a schematic view in front elevation, of the inside of the store in Figure 1 , with the drawers in the respective formation chambers;

[0096] - Figure 4 is a schematic view similar to Figure 3 with a drawer displaced from the respective formation chamber;

[0097] - Figure 5 is a schematic representation of the functional relationships between the components of a drawer of the store in Figure 1 and the electrochemical cells of trays housed in the drawer.

[0098] With reference to the accompanying figures, 10 denotes a store made in accordance with the present invention, particularly configured to subject electrochemical cells 1 for battery production to a formation process.

[0099] The store 10 is part of a consolidation plant set up to receive electrochemical cells 1 , not illustrated, e.g. from a packaging plant, and subject them to a formation and aging process so that they are basically ready for use.

[0100] In the preferred example described here, the electrochemical cells 1 are secondary, cylindrical, lithium-ion electrochemical cells, and are brought to the store 10, by means of suitable transport systems, housed in special trays 11 .

[0101] Each tray 11 has a generic box shape open at the top, and comprises a base surrounded by side walls. A plurality of seats configured to accommodate a respective plurality of electrochemical cells 1 according to a predefined vertical orientation is defined within the tray 11 . At each seat of the tray 1 1 , the base is suitably perforated to allow access to the lower ends of the electrochemical cells 1 housed therein.

[0102] The size and materials, as well as the number of seats in the tray 11 , is variable depending on the type of electrochemical cells 1 to be formed. By way of example, each tray 11 can contain 64 electrochemical cells 1 .

[0103] The store 10 comprises a load-bearing frame 12, defining an internal shelf structure and confined externally by walls 13. Access to the internal space of the store 10 is ensured by an opening 14, located at the base of the store 10 and sized to allow the entry and exit of the trays 11 .

[0104] The internal structure of the store 10 defines a plurality of formation chambers 15 superimposed in distinct columns, arranged, for example, in two separate rows.

[0105] The store 10 further comprises a transport system 16, arranged inside the store 10, preferably between the two rows of columns of formation chambers 15, configured to transport the trays 11 from the opening 14 and the formation chambers 15.

[0106] In order to facilitate the movement of the trays 11 between the inside and the outside of the store 10, a transfer station 18 is preferably provided at the opening 14 which, from time to time, either receives the trays 11 from the outside to deliver them to the transport system 16 or receives the trays 11 from the transport system 16 to deliver them to the outside.

[0107] The transport system 16 comprises a support surface 17, on which the tray to be moved within the store 10 is placed, a first translation member, configured to move the support surface 17 along vertical uprights 19a and a second movement member, configured to move the support surface 17 along horizontal guides 19b. In this way, the transport system 16 is able to reach all the formation chambers 15 of the store 10.

[0108] The store 10 further comprises a plurality of drawers 20, each removably housed within a respective formation chamber 15.

[0109] Each drawer 20 comprises a plurality of housings 21 , configured to receive and support respective trays 11 containing electrochemical cells 1 to be subjected to the formation process, a corresponding plurality of formation modules 22, arranged to apply a modulated voltage or current to the electrochemical cells 1 leading to the formation of the electrochemical cells 1 , as well as a power supply unit 23 configured to supply a suitable current and voltage to the various formation modules 22.

[0110] Each formation module 22 comprises a contacting assembly 24 configured to provide electrical contacts for each electrochemical cell 1 contained in the tray 11 in a housing 21 .

[0111] Each formation module 22 also comprises a plurality of bidirectional electrical converters 25, suitably connected to the contacting assembly 24 to supply and receive electrical current to and from each electrochemical cell 1 in the tray 11 .

[0112] In particular, it is envisaged that each formation module 22 comprises a number of bidirectional electrical converters 25 equal to the number of electrochemical cells 1 present in a tray 11 , e.g. 64.

[0113] Each bidirectional electrical converter 25 is designed to transform an input current, e.g. a 12-Volt direct current, into an output current having the voltage required by the specific step of the formation process, e.g. between 0 and 5 Volts.

[0114] Each formation module 22 further comprises a plurality of electronic control units 26 configured to perform, via the bidirectional electrical converters 25 and the contacting unit 24, the electrical charge and discharge cycles of the electrochemical cells 1 required by the formation process.

[0115] The electronic control units 26 and bidirectional electrical converters 25, suitably grouped, are preferably mounted and connected to each other on respective electronic boards.

[0116] The plurality of electronic control units 26 and bidirectional electrical converters 25 are preferably integrated with the contacting assembly 24, so that each formation module 22 forms an individually manipulate unit.

[0117] Each formation module 22 thus composed, is positioned under a respective housing 21 and is mounted on a respective movement member 27 arranged to move the formation module 22 between an operational position, wherein the formation module 22 is raised towards the housing 21 , and a non-operational position, wherein the formation module 22 is lowered away from the housing 21.

[0118] When the formation module 22 is moved to the operational position, the contacting assembly 24, located at the top of the formation module 22, passes through the holes made in the base of the tray 11 with its special appendages (pins), so as to establish electrical contactwith the electrochemical cells 1 housed in the seats of the tray 11 .

[0119] Each formation module 22 can be moved between the operational and non- operational position independently of the other formation modules 22 on the same drawer 20.

[0120] The power supply unit 23 also comprises a plurality of bidirectional electrical converters 28 capable of transforming an input current from an external network R, e.g. a 380 Volt alternating current, into an output current suitable for supplying the formation module 22, e.g. a 12 Volt direct current.

[0121] The power supply unit 23 comprises fewer bidirectional electrical converters 28 than the number of formation modules 22.

[0122] Each bidirectional electrical converter 28 of the power supply unit 23 is connected to all the formation modules 22 of the same drawer 20.

[0123] The power supply unit 23 is removably mounted on the drawer 20 and is connected to the formation modules 22 via a cable system that allows the formation modules 22 to move between the operational and non-operational position, while the power supply unit 23 remains solidly constrained to the drawer 20.

[0124] The power supply unit 23 is connected to an external power supply R with a removable connection provided at each formation chamber 15.

[0125] The store 10 further comprises a maintenance station 30, for example on the opposite side to the opening 14, where each drawer 20 can be brought to facilitate maintenance of one or more of its components. In particular, it is advantageously envisaged that the operation of moving the drawers 20 between the respective formation chambers 15 and the maintenance station 30 is carried out by the transport system 16, using the same transport to move within the store 10 both the trays 11 and the drawers 20.

[0126] The electrochemical cells 1 contained in a tray 11 are formed as follows.

[0127] The tray 11 is brought to the store 10 and placed in the transfer station 18 which moves the tray 11 to the support surface 17 of the transport system 16 which, in turn, moves the tray 11 to the formation chamber 15 assigned by a management and control system of the store 10. The tray 11 is then deposited in a free housing 21 of the drawer 20.

[0128] The formation module 22 is then lifted by the movement member 27 to the operational position, where the contacting assembly 24 makes contact with the individual electrochemical cells 1 contained in the tray 11 .

[0129] At this point, the step of forming the electrochemical cells 1 is initiated, with an appropriate succession of electrical charge and discharge cycles controlled by the electronic control unit 26 via the bidirectional electrical converters 25.

[0130] The duration of the step of forming the electrochemical cells 1 depends on the construction specifications of the cells and varies between 10 and 15 hours.

[0131] At the end of the formation step, the formation module 22 is lowered by the movement member 27 into the non-operational position and the tray 11 is taken out of the housing 21 by the transport system 16 and brought to the opening 14, and from there, via the transfer station 18, to the outside of the store 10.

[0132] It will be noted that the step of forming the electrochemical cells 1 in a tray 11 can proceed substantially independently of the presence or absence of other trays 11 in the same drawer 20, although it is preferred, for reasons of productivity and maximum utilisation of the available volume, that all the housings of the drawer 20 are occupied by respective trays 11 .

[0133] Should a component of a drawer 20, such as a bidirectional electrical converter 28 or a formation module 22, malfunction or when the pre-set period for scheduled overhauls has elapsed, the drawer 20 is removed from the formation chamber 15 and, via the transport system 16 is brought to the maintenance station 30 to allow for the appropriate interventions. This solution thus solves the technical problem identified above, while at the same time achieving further advantages also deriving from the specific embodiments described above.

[0134] It goes without saying that, in order to meet specific and contingent application needs, a person skilled in the art will be able to make further modifications and variants to the solution described above that are nevertheless within the scope of protection defined by the following claims.

Claims

CLAIMS1 . Store (10) for the formation of electrochemical cells (1 ) for battery production, in which a plurality of formation chambers (15) is defined and comprising a plurality of drawers (20), each removably housed in one of said formation chambers (15), wherein each drawer (20) comprises:- a plurality of housings (21 ), each configured to accommodate a respective tray (11 ) containing said electrochemical cells (1 ),- a plurality of formation modules (22), each formation module (22) comprising: i. a contacting assembly (24) configured to provide an electrical contact for each electrochemical cell (1 ) contained in said tray (11 ) when accommodated in one of said housings (21 ), ii. at least one bidirectional electrical converter (25) connected to said contacting assembly (24) to supply and receive electrical current to and from said electrochemical cells (1 ), and iii. an electronic control unit (26) configured to apply to said electrochemical cells (1 ), by means of said contacting assembly (24) and said at least one bidirectional electrical converter (25), a modulated voltage or current such as to allow the at least partial formation of said electrochemical cells (1 ),- a power supply unit (23) connected to each formation module (22) and configured to transform an input electric current, having a first voltage, into an output electric current, having a second voltage, which is lower than said first voltage and adapted to supply said formation modules (22).

2. Store according to claim 1 , wherein each formation module (22) is associated with a respective housing (21 ) defined in said drawer (20).

3. Store according to claim 1 or 2, wherein each formation module (22) is movable with respect to said drawer (20) between an operational position wherein said contacting assembly (24) is moved towards a tray (11 ) received in said housing (21 ) and a non-operational position wherein said contacting assembly (24) is distanced from said tray (11 ).

4. Store according to claim 3, wherein each drawer (20) comprises a respective movement member (27) associated with each formation module (22) for moving the formation module (22) between said operational position and said non-operational position.

5. Store according to claim 3 or 4, wherein said power supply unit (23) remains integral with said drawer (20) while said formation module (22) is moved between said non-operational position and said operational position.

6. Store according to any one of the preceding claims, wherein said power supply unit (23) comprises a plurality of electrical converters (28) and each electrical converter (28) is connected to each formation module (22).

7. Store according to any one of the preceding claims, wherein said contacting assembly (24), said at least one bidirectional electrical converter (25) and said electronic control unit (26) are integrated with each other in said formation module (22).

8. Store according to any one of the preceding claims, wherein a transfer station (18) is defined, configured to receive said trays (11 ) at an entrance (14) of said store (10).

9. Store according to any one of the preceding claims, comprising an internal transport system (16), configured to transport said tray (11 ) from an entrance (14) of said store (10) to one of said housings (21 ).

10. Store according to claim 9, wherein said internal transport system (16) is configured to move said drawer (20) to and from said formation chamber (15).

11. Store according to any one of the preceding claims, comprising a maintenance station (30) and said drawer (20) is movable from said formation chamber (15) to said maintenance station (30).

Images