Apparatus for stacking a separator strip and sheets of metal foil, and method for creating a stacked structure of a separator strip, preferably for an electrochemical cell intended for producing batteries

Abstract

A stacking apparatus (100) for stacking a separator strip (NS) and sheets of metal foils (201, 301), comprising a dispensing unit (200) for dispensing said separator strip (NS) along a predetermined feed path (PA), a stacking unit (1) comprising a stacking surface (10) configured so as to receive said separator strip (NS) and said sheets of metal foil (201, 301), a first movement device (131) configured to move an outgoing orientation control device (R2) reversibly along a displacement direction (d) wherein said first movement device (131) comprises an alignment device (205') configured to displace said outgoing orientation control device (R2) so as to align said separator strip (NS) with said predefined feed path (PA).

Description

[0001] DESCRIPTION

[0002] APPARATUS FOR STACKING A SEPARATOR STRIP AND SHEETS OF METAL FOIL, AND METHOD FOR CREATING A STACKED STRUCTURE OF A SEPARATOR STRIP, PREFERABLY FOR AN ELECTROCHEMICAL CELL INTENDED FOR PRODUCING BATTERIES

[0003] The present invention relates to an apparatus for stacking a separator strip and foil sheets, e.g. of the type formed by stacking a separator strip alternated with sheets of metal foils.

[0004] The invention is also directed to a method for stacking a separator strip and sheets of metal foils.

[0005] The present invention finds a preferred, though not exclusive, application in the field of electrochemical cell production intended, for example, for the production of pouch-type or prismatic batteries, for the manufacture of which a stacked structure of a separator strip preferably alternated with sheets of metal foils is used.

[0006] In particular, in the relevant technical field, it is known to combine several stacked layers of a separator strip folded on itself with electrode sheets of metal foils, interposed between the different layers, in order to form a structure that can be used for creating an electrochemical cell for producing batteries.

[0007] An example of an apparatus and method for creating batteries by stacking separator strips alternated with sheets of metal foils provides for displacing a stacking unit by means of a controlled pendulum movement using a servo motor and a speed reducer.

[0008] In the present disclosure, as well as in the accompanying claims, certain terms and expressions are deemed to assume, unless otherwise expressly indicated, the meaning expressed in the following definitions.

[0009] The term "separator strip" is intended to mean any solid product which, within an industrial production line, is presented in the form of an elongated strip or ribbon, i.e. an element in which the longitudinal extension is significantly greater than its transversal extension. This separator strip can be formed by a single strip or ribbon of material, or by several overlapping strips so as to form a multilayer.

[0010] The separator strip also has characteristics such as to allow some flexing during its advancement along a relative production line. The separator strip can, for example, be used by making overlaps of alternating insulating layers so as to form a stacked structure or sandwich for creating an electrochemical cell.

[0011] Furthermore, the term "separator strip" indicates a strip-shaped product that has the characteristic of allowing a form of separation and / or isolation with respect to other parts placed near it.

[0012] This separation can take place through physical or chemical characteristics depending on the intended conditions of use.

[0013] An example of such a separation characteristic may be represented by an electrically insulating polymeric strip placed in contact with sheets of metal foils of conductive electrodes.

[0014] This specific configuration mentioned is merely an example and not a limitation.

[0015] In this context, the term "stacking" means the action adapted to create a structure comprising a plurality of layers of a separator strip folded on itself so as to create a continuous structure adapted to separate or isolate other components interposed between the different levels of separator material made.

[0016] The term "stacked structure" means any structure formed by stacking, i.e. folding on itself, a strip, a ribbon or more generally a strip-shaped article, creating several superimposed layers according to their projection or superimposition, preferably vertical. It can be seen that this stacked or folded structure is aimed at producing at least partial separation with respect to potential products interposed between the various layers and does not necessarily require direct contact between the different layers of the strip adopted.

[0017] Often this stacked structure is also identified as a "Z-structure" precisely depending on the folded shape that the different layers make up.

[0018] As mentioned above, this stacked structure can be applied not only in the field of electrochemical cells but also in other sectors, such as for example in that of conductors or capacitors within which stacked structures can also be used.

[0019] The term "working path" means a closed path that a movement device or similar kinematic element performs in which the initial point and the final point of the path substantially coincide. The term "continuous" referred to an expression of motion, is intended to mean an operation that takes place without interruption, without there being a stop or an interruption in the operation in question. In particular, with preferred but not exclusive reference to the feeding or movement of a strip, the term "continuous" indicates that the strip is never stopped during its feeding or movement.

[0020] Similarly, the term "continuous" refers to a product, for example the separator strip, which does not provide for interruptions or clear separations inside and which therefore presents itself as a single body during the processing or use steps considered.

[0021] Additionally, as previously argued, it is considered that the strip adopted in the different enucleatable steps of the industrial process of interest is preferably a continuous separator strip and that, therefore, this technical solution involves a folding step of this continuous separator strip on itself in order to make at least two superimposed layers of the aforementioned stacked structure, thus emphasizing at least one procedural difference with respect to technologies adopted in the sequential stacking of individual layers or plurality of previously preformed or pre-cut separator layers (a concept that provides for the simple release of pre-structured architectures and identifiable with the most restrictive meaning of the term "stacking").

[0022] With the term "substantially constant" referred to a measurement or quantity, such as for example the displacement angle of an object during its trajectory, i.e. the angle formed by an object during its displacement, it is meant that this measurement or quantity maintains, over time, a value that preferably varies by a maximum of ±10%, preferably by a maximum of ±5%, even more preferably by a maximum of ±2%.

[0023] The term "direction" refers to an identifiable vector having direction and direction as described or represented in the description and any attached figures. In other words, in this context when the term direction is used it is meant an oriented direction. In some disclosures, the components of a free vector that are its direction, sense and norm or magnitude (or, less properly, scalar modulus) are explained in order to describe them in a more precise and detailed way. More specifically, in this context "norm" is referred to by identifying it as the Euclidean distance between two points, respectively initial and final, of a distance vector, i.e. the square root of the sum of the squares of its components. The term "substantially equal to 0 mm" means a minimised value that may deviate from the exact value of 0 mm for mere dimensional dimensions of the kinematics involved that may vary this condition by a few millimetres.

[0024] The terms "upstream" or "downstream" refer to objects or process steps that occur before or after a specific sequential flow, respectively. When these terms refer to the "direction of unwinding of a separator strip", it means that they occur respectively in previous or subsequent steps with respect to the path that the separator strip runs according to its feed direction, starting from an initial release or dispensing element (roll, coil, etc.) up to the stacking surface on which it is stacked.

[0025] In this context the term "unfold" is a synonym for "unfolding".

[0026] Moreover, in the examples and arguments given, the terms "sheet of metal foil" can be replaced by "electrode" when the embodiments refer to applications for electrochemical cells.

[0027] With the terms "as following according to at least one component" referred to B chasing A is meant that the displacement of A is in agreement with B, that is, the displacement vector of B and A have the same equal component.

[0028] In this context, the terms "same angular orientation in all assumable spatial configurations" mean that a certain arrangement of devices or objects to which a set of vectors specifically oriented in space is uniquely correlatable does not change this orientation of the set of vectors regardless of the assumed spatial configurations. In other words, when this condition occurs, the displacement operators applied to this set of vectors only produce allowed translations and not rotations.

[0029] By the terms "Y immediately downstream of X" is meant that a device or product Y is sequentially identifiable immediately after X without further intervening devices or products.

[0030] Consistently, the expression "Y immediately upstream of X" identifies a device or product or process step that is sequentially (and not distantly) immediately before X.

[0031] The term "selectively extending" means modifying the extension of an object or portion, producing an increase free of pre-imposed geometric constraints or restrictions.

[0032] The terms "during the creation of said stacked structure (S)" are intended to refer to an action or process condition that occurs during any of the steps included in the creation of said stacked structure.

[0033] The term "consistent" referred to the movement of two or more elements, is intended to mean that these elements perform substantially the same movement and substantially simultaneously. This term is understood as a synonym of integral with a broader meaning with regard to the structural constraints involved.

[0034] In other words, two elements that move according to a consistent movement carry out a solidary movement, as a single body, although not necessarily one is united or constrained directly to the other and being, potentially, also related to different units and parts of the apparatus. In fact, it may be provided that the respective movement systems of the two elements are configured, programmed or actuated in such a way as to move, when necessary, the two elements together in a coordinated manner. In addition, for example, the use of a temporary constraint, physical or digital, can be provided between the two elements which, for example, joins and coordinates them to each other in some process steps, making them move together, and separates them again, making them mobile independently of each other.

[0035] It should also be specified that the expression "to displace an object between a first position and a second position" is intended to mean both the displacement from the first position to the second position and the displacement from the second position to the first position.

[0036] This definition applies in an analogous way to similar expressions of motion, such as for example to transfer or to move a generic object between two positions or between two zones or even between two different operating configurations.

[0037] The Applicant, in the context of the constant need to increase the performance and efficiency of production processes, has previously observed how, in a production line for the creation of a stacked structure suitable for use in the creation of an electrochemical cell intended for producing batteries, the feed rate of a separator belt with respect to the unit that performs the stacking can constitute an important element of limitation of the production capacity of the line itself. Moreover, this limitation is even more critical in the event that high precision is required in the formation of the stacked structure.

[0038] In particular, the Applicant has observed that in many applications, such as for example in the production of electrochemical cells, high precision must be guaranteed in the geometry of the stacks and in the steps of positioning the electrode sheets of metal foils between one stacked layer and another in order to guarantee the performance required of the finished product.

[0039] Furthermore, the Applicant has previously observed that in the aforementioned production line for the creation of a stacked structure it is necessary to fold up to 180° a layer of separator strip in order to produce a subsequent one superimposed and vertically aligned with the underlying one.

[0040] The Applicant has observed that the separator strip is then made to displace and change angular orientation significantly during the creation steps of the stacked structure, producing over time a complex evolution of the feed direction of the separator strip along the entire feed line up to the predetermined stacking surface.

[0041] Moreover, thanks to targeted studies and in-depth studies, the Applicant has observed that such rapid movements in space and variations in the angular orientation of the separator strip during the stacking process can produce significant damage to the strip itself.

[0042] The Applicant has in fact observed that when the direction of unwinding of the separator strip changes over time, conditions of asymmetry of the fluid-dynamic lateral pressures acting on the advancing separator strip can be created.

[0043] The Applicant has internally identified and named this phenomenon with the terms "sail effect".

[0044] The Applicant has observed that such asymmetrical conditions of the sail effect can produce significant both microscopic and macroscopic deformations in the structure of the separator strip thus introducing a potentially critical step of damage to the material that constitutes an essential component of the stacked structure.

[0045] Moreover, the Applicant has observed that such micro and macro-deformations of the structure of the separator strip can lead to the formation of unwanted states of tension, risking even creating breaks in the strip, when related to conditions of excessive tension, or states of uncontrolled relaxation, even localised, when related to conditions of loss of tension, which can lead to the manifestation of folds and ripples potentially compromising the efficient alignment of the various layers and the correct contact between the stacked surfaces. Furthermore, the Applicant has observed that these problems related to the damage of the structure of the separator strip and / or the realization of non-constant and uniform states of tension with significant irregularities in the contact surfaces made can be critically significant in the specific case of application in the electrical field in which the desired conditions of insulation or contact between different parts must be absolutely guaranteed with maximum reliability and reproducibility.

[0046] In fact, the applicant observed that such conditions may lead to displacements and / or deformations of the separator strip and may compromise the ideal alignment of the different parts intended for the composition of the battery.

[0047] Furthermore, the Applicant has noted that such unwanted misalignments of the separator strip can also occur without obvious damage to the structure of the material, but as a direct consequence of a complex set of movements to which the strip is subjected during the processing process.

[0048] The Applicant has observed that this harmful and imprecise operating condition created on the separator strip is also related to the feed rate, and therefore of displacement in space, of the separator strip itself during the unwinding and stacking steps.

[0049] The Applicant has therefore perceived how it is possible to improve the precision and stacking yield of the separator strip compared to known solutions by compensating for the production of any deformations and misalignments in the separator strip during the formation of the stacked structure.

[0050] Finally, the Applicant has found that by constantly intervening on the spatial development of the feed path of the separator strip, and in particular, the part of the separator strip close to the conditions of asymmetry of the fluid dynamic lateral pressures, it is possible to speed up the unwinding and stacking operations by improving the dimensional precision and spatial development of the stacked structure, while minimizing or avoiding uncontrolled and harmful states of tension on the strip.

[0051] In addition, the Applicant has observed that this invention can also be advantageously exploited in the steps in which the strip is gripped to begin stacking on a desired stacking surface or when cutting the separator strip as well as when a sheet of metal foil is placed on it.

[0052] In a first aspect thereof, therefore, the present invention is directed to a stacking apparatus preferably for stacking a separator strip and sheets of metal foils.

[0053] Preferably, said apparatus comprises a dispensing unit for dispensing said separator strip along a predefined feed path.

[0054] Preferably, said apparatus comprises a stacking unit comprising a stacking surface configured so as to receive said separator strip and said sheets of metal foils. Preferably, said separator strip and said foils are in mutual overlapping relationship.

[0055] Preferably, said apparatus comprises a first movement device configured to move an outgoing orientation control device acting on said separator strip.

[0056] Preferably, said outgoing orientation control device is placed immediately upstream of said stacking unit.

[0057] Preferably, said first movement device configured to move an outgoing orientation control device reversibly along a direction of travel between a first configuration distal to said dispensing unit and a second configuration proximal to said dispensing unit.

[0058] Preferably, said first movement device comprises an alignment device configured to displace said outgoing orientation control device so as to align said separator strip to said predefined feed path.

[0059] Thanks to this technical solution, it is possible to intervene effectively just before the stacking unit, guaranteeing a predefined alignment of the separator strip.

[0060] It is thus immediately clear that in this way an improved stacking precision of the separator strip and therefore a greater efficiency of the process involved can be guaranteed.

[0061] Based on a second aspect, the present invention also refers to a method for creating a stacked structure of a separator strip, preferably for an electrochemical cell intended for producing batteries. Preferably, said method comprises dispensing said separator strip through a dispensing unit along a predefined feed path.

[0062] Preferably, said method comprises stacking said separator strip on a movable stacking surface.

[0063] Preferably, said method comprises moving an outgoing orientation control device, acting on said separator strip and placed upstream of said stacking unit, reversibly along a displacement direction between a first configuration distal to said dispensing unit and a second configuration proximal to said dispensing unit by means of a first movement device.

[0064] Preferably, said method comprises arranging an alignment device, included in said first movement device, configured to displace said outgoing orientation control device.

[0065] Preferably, said method comprises identifying a possible alignment difference between said separator strip and said predefined feed path.

[0066] Preferably, in case said alignment difference is other than zero, said method comprises actuating said alignment device and displacing said outgoing orientation control device so as to align said separator strip to said predefined feed path while said separator strip is being continuously dispensed.

[0067] Also thanks to this second aspect of the present invention it becomes possible to guarantee a more precise and reproducible stacking of the separator strip while maintaining a high process efficiency.

[0068] The present invention, in at least one of the aforesaid aspects, may have at least one of the further preferred features set forth below.

[0069] Preferably said alignment is carried out while said separator strip is fed continuously.

[0070] In this way, it is possible to achieve this alignment of the separator strip, obtaining an improved yield process free of unwanted stops in the operating steps.

[0071] Preferably, said alignment device is configured to move said outgoing orientation control device, acting on said separator strip, according to a translation direction transverse to said predefined feed path. In this way it is possible to produce an improved correction of the alignment of the strip that turns out to be punctually localized and advantageously rapid in its implementation.

[0072] Preferably, said alignment device comprises a first frame including said outgoing orientation control device on which a first roller and a second roller are arranged.

[0073] Preferably, said first and second rollers are rotatable respectively around a first and a second longitudinal axis, which are housed so as to be placed side by side to and spaced apart from each other so as to engage said separator strip between them along said predefined feed path.

[0074] Preferably, said first frame is translatable according to said translation direction having a component parallel to said first and second longitudinal axis.

[0075] In this way it is possible to ensure an efficient control of the strip while realizing an effective form of alignment.

[0076] Preferably, said translation direction is substantially parallel to said first longitudinal axis.

[0077] In this way, alignment of the strip is realised efficiently, cost-effectively and quickly.

[0078] Preferably, said first roller and / or said second roller are constrained with an allowed rotation to an eccentric shaft.

[0079] In this way it is possible to correct any mutual abutment or contact errors on the separator strip.

[0080] Preferably, said second roller is constrained to a bracket.

[0081] Preferably, said bracket is constrained to said first frame with an allowed translation and is configured to reversibly move between a close position, wherein said second roller is at a minimum distance from said first roller and a spacedapart position, wherein said second roller is at a maximum distance from said first roller.

[0082] In this way, it is advantageously possible to displace the second roller to adapt different strip formats while facilitating the passage of the strip, particularly when there is an initial end that may be subject to unwanted flexing or curvature.

[0083] Preferably, said first and second rollers have substantially equal diameters and are constrained to the first frame by unidirectional joints or joints.

[0084] In this way, it is possible to avoid inducing surface deformations and to guide the transit of the separator strip effectively, further achieving the possibility of local movement of the separator strip with respect to the feed rate upstream of them.

[0085] Preferably, said second roller is connected to a motor element, preferably a stepper or brushless electric motor, so that it can be selectively actuatable in rotation.

[0086] In this way, the actual speed rate of the strip can be further determined at the outgoing orientation control device.

[0087] Preferably, said apparatus comprises a second movement device of said stacking surface configured to displace said stacking surface along a second working path.

[0088] Preferably, said second path defines a closed curve.

[0089] In this way, the Applicant found that it was possible to overcome the limitations of the prior art by preventing the second working path of the stacking surface from having inversion points, i.e. points at which the displacement speed of the stacking surface was zero.

[0090] This solution is not feasible when the second path defines a segment (straight or curved) or an open curve where the ends of the path do not coincide.

[0091] In other words, the Applicant found that by avoiding inversion points, it is possible to maintain a continuously moving stacking surface even by producing conditions of relative "moving stops" between different devices.

[0092] Thanks to this technical solution, the Applicant found that it was not only possible to reduce process times, but also to avoid abrupt slowdowns and accelerations, thus increasing the average life of the movement devices involved and significantly reducing unwanted stresses that could be created on the separator strip.

[0093] Preferably, said first and / or second movement device(s) is / are configured to maintain a first distance between said outgoing orientation control device and said stacking surface, measured according to an outgoing reference direction, between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm. Preferably, the first distance is measured according to said outgoing reference direction.

[0094] Preferably, the first distance is comprised between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm.

[0095] The Applicant has found that thanks to these features it is possible to maintain a sufficiently small distance between the outgoing orientation control device and the stacking surface. This distance is preferably defined taking into account the dimensional overall dimensions of the kinematics involved.

[0096] In this way, it is possible to minimise the sail effect on the section of the strip downstream of the outgoing orientation control device by reducing the extent of this tract. In fact, the Applicant has found that if it is necessary to significantly vary the angular orientation of the separator strip to be stacked, it is possible to act downstream of the outgoing orientation control device by reducing the amount of separator strip that may be exposed to orientation variations and thus to asymmetrical fluid dynamic lateral pressure conditions. In this way, the damage caused by the sail effect can be significantly reduced or eliminated.

[0097] Further, the Applicant realised that it is possible to increase or decrease the longitudinal length of the separator strip, thereby de facto realising an unwinding or winding of the separator strip, as the sail effect is only created when such changes in extension are accompanied by a change in angular orientation.

[0098] In this way, the Applicant has at least partially solved the problems of the prior art by defining a first distance between the outgoing orientation control device and the stacking surface sufficiently contained so as to place constraints on displacements having components parallel to the direction of the first distance, while allowing greater freedom of movement when the displacements occur in the directions close to a condition of perpendicularity to the reference direction of the strip exiting the outgoing orientation control device.

[0099] Preferably, said first distance is substantially constant for at least 40%, more preferably for at least 50%, more preferably for at least 80%, even more preferably for 100% of the time of said second working path.

[0100] In this way, it is possible to effectively reduce the sail effect for a significant portion of the process steps related to the unwinding and stacking action of the separator strip while keeping the first distance constant over time and equal to a predetermined value. Furthermore, it is possible to provide predetermined and limited variations of this first distance specifically aimed at producing further benefits without compromising the tension state or inducing damage in the separator strip to be stacked while still ensuring a high overall process speed.

[0101] Preferably, said first movement device of said outgoing orientation control device is configured as following according to at least one component to said second movement device when it displaces said stacking surface with a continuous movement.

[0102] In this way, it can provided for the accumulation tract to change according to the movements of the stacking surface, providing a desired additional amount of separator strip to be used for movements where the state-of-the-art solutions necessarily involve stops.

[0103] In other words, this solution avoids interruptions in the supply and movement of the separator strip that could generate unwanted tension states or otherwise decrease the productivity of the apparatus.

[0104] According to a embodiment of said method, said alignment device comprises a first frame on which a first roller and a second roller are arranged, respectively rotating about a first and a second longitudinal axis, which are housed so as to be placed side by side to and spaced apart from each other so as to engage said separator strip between them along said predefined feed path.

[0105] Preferably, said first frame is translatable according to a translation direction having a component parallel to said first and second longitudinal axis.

[0106] In this way it is possible to ensure an efficient control of the strip while realizing an effective form of alignment.

[0107] Preferably, said method comprise stacking said separator strip at said stacking surface.

[0108] Preferably, said stacking of said separator strip takes place by maintaining a first distance between said outgoing orientation control device and said stacking surface, measured according to said outgoing reference direction of said separator strip, between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm.

[0109] Also based on this aspect it is possible to achieve the same advantages described in relation to the previous aspect.

[0110] Preferably, said first movement device is configured to displace said outgoing orientation control device between an approached configuration, wherein said outgoing orientation control device (is at a minimum distance from said first orientation control device, said minimum distance being measured according to the length of said separator strip when it is comprised between said first orientation control device and said outgoing orientation control device, and an extended configuration, wherein said outgoing orientation control device is at a maximum distance from said first orientation control device, said maximum distance being measured according to said length of said separator strip when it is comprised between said first orientation control device and said outgoing orientation control device,

[0111] Preferably, said first movement device is configured to displace said outgoing orientation control device in such a way as to maintain the same angular orientation in all spatial configurations assumed by said separator strip between said close configuration and said extended configuration at said accumulation tract.

[0112] Preferably, said first movement device is configured in such a way that the only part of said separator strip downstream of said outgoing orientation control device that varies angular orientation during the creation of said stacked structure of said separator strip is a final tract defined downstream of said outgoing orientation control device and upstream of a first constraint position and / or a second constraint position of said separator strip with respect to said stacking surface.

[0113] Thanks to this technical solution, it is possible to have a desired accumulation of separator strip to be used as required by the process, allowing the tension of the separator strip to be kept constant and ensuring that the sail effect is nullified in the accumulation tract upstream of the outgoing orientation control device and minimised or avoided in the section downstream of the outgoing orientation control device. In this way, the separator strip can be stacked on the stacking surface, minimising the damage caused by the sail effect, keeping the tension on the separator strip constant and ensuring the desired precision of the stacked structure. Preferably, said final tract is oriented according to a deviation direction, which can be identified immediately downstream, with respect to said unwinding direction of said separator strip, of said outgoing orientation control device.

[0114] Preferably, said deflection direction defines a deviation angle with respect to said outgoing reference direction.

[0115] Preferably, said movement unit is configured to displace said outgoing orientation control device relative to said stacking surface by defining a second distance between said outgoing orientation control device and said stacking surface.

[0116] Preferably, said second distance is defined so as to: reduce said second distance to the minimum when said deviation angle is comprised between +80° and -80°, and / or selectively extend said second distance when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0117] Thanks to this solution, it is possible to acquire greater freedom and process adaptability or modularity, possibly even modifying the extension of the final tract of the separator strip without producing significant contributions to the sail effect, while maintaining a high process speed and guaranteeing constant separator strip tension.

[0118] Preferably, when said deviation angle is comprised between +80° and -80° said second distance is substantially equal to said first distance.

[0119] This keeps the final tract of the separator strip as small as possible when the strip has to vary significantly in angular orientation, i.e. when the deviation angle value varies, in order to reduce or eliminate the sail effect that could potentially be generated.

[0120] Preferably, when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100° said second distance is comprised between 0% and 10% of a maximum length between a first constraint position and a second constraint position.

[0121] Thanks to this technical solution, it is possible to further vary the extension of the final tract, also according to specific formats of the stacked structure to be created and / or to avoid possible interference of the kinematics provided in the apparatus. Preferably, when said deviation angle is substantially equal to +90° or -90°, said first distance varies

[0122] • when approaching said stacking surface, from said constant value by a value comprised between said first distance and 200% of said first distance, or

[0123] • when moving away from said stacking surface, from said constant value to a value comprised between said first distance and 200% of said first distance.

[0124] In this way, it is possible to displace the stacking surface beyond the condition of perpendicularity with respect to the displacement direction reference direction, thus bringing the portion of the final tract of the separator strip superimposed on the stacking surface to an improved match on it, thus increasing the precision in the creation of the stacked structure; alternatively, it is possible to increase the extension of the final tract in order to more effectively avoid possible interactions between the kinematics involved.

[0125] For further clarity, an approaching displacement identifies a reciprocal displacement that begins by reducing the value of the distance between the outgoing orientation control device and the stacking surface. It is to be understood that, when the amount of approaching displacement is equal to 100% of the first distance, the actual distance present between the outgoing orientation controller and the stacking surface becomes zero, while when the amount of approaching displacement is greater than 100% of the first distance, it is to be understood that the actual distance present between the outgoing orientation controller and the stacking surface begins to increase again while maintaining the same direction of approach, when the amount of approaching displacement is equal to 200% of the first distance, the outgoing orientation control device is on the opposite side of the stacking surface with respect to the initial configuration corresponding to the first distance, such that the distance between the output control device and the stacking surface assumes a value equal to 100% of said first distance, but on the opposite side with respect to the stacking surface. Preferably, said first constraint position and / or said second constraint position of said separator strip with respect to said stacking surface are / is a point at which said separator strip is respectively constrained by a first and / or second clamping device included in said stacking unit at said stacking surface. In this way, it is possible to constrain and precisely define the portions of the final tract of the separator strip to be stacked in order to achieve the desired stacked structure. At the same time, by defining the final tract of the constraint point, it is possible to manage and minimise the portion of the separator strip potentially exposed to asymmetrical conditions of lateral fluid-dynamic pressures that produce the sail effect.

[0126] According to the preferred embodiment, the first and / or second clamping devices are grippers or suction cups or electromagnetic systems adapted to selectively retain a portion of the separator strip in a manner integral to the stacking surface.

[0127] In this way, it will be possible to constrain the desired portion of the final tract reversibly and according to predetermined time sequences at different points.

[0128] According to embodiments, the stacking surface has a substantially planar development with a substantially rectangular base. It can be dimensioned according to the desired format of the stacked structure to be realised.

[0129] Preferably, the first and / or second clamping device are constrained with an allowed coplanar translation with respect to the stacking surface.

[0130] In other words, the first and / or second clamping device are constrained relative to the stacking surface with the clamping position varying in the direction of the distance between them.

[0131] In this way, the desired stacking surface format can be easily and quickly adapted to the stacking surface adopted.

[0132] Preferably, the first and / or second clamping device are constrained with an allowed translation perpendicular to the stacking surface.

[0133] Thanks to this technical solution, it will be possible to constrain the separator strip more effectively to the stacking surface as the creation of the stacked structure proceeds.

[0134] Preferably, said apparatus comprises a first and / or second release assembly of a sheet of metal foil.

[0135] Preferably, said first and / or said second sheet assembly of a sheet of metal foil is configured with respect to said second movement device to release, at a minimum release distance from said stacking surface on a portion of said separator strip at said stacking surface, a first or second sheet of metal foil upon an approaching movement of said first or second assembly of a sheet of metal foil with respect to said stacking surface during a receiving tract of said second working path.

[0136] Preferably, said approaching movement is configured so as to produce a condition of substantially zero relative speed between said first and / or said second release assembly of a sheet of metal foil and said stacking surface and having at least one displacement component parallel to said outgoing reference direction, preferably perpendicular to said stacking surface, more preferably vertical.

[0137] In this way, it is possible to manage the creation of the stacked structure with the electrode sheet of metal foil interposed between the layers of separator strip, optimising the alignment of the electrodes in the release step in order to precisely and efficiently achieve the desired electrochemical cell.

[0138] In particular, when the release takes place with a purely vertical approaching movement, unwanted horizontal displacements are avoided and thus an even more precise, reliable and reproducible release and transfer of the sheet of metal foil can be produced.

[0139] Preferably, said end tract is oriented according to a deviation direction, identifiable downstream of said outgoing orientation control device, and defining a deviation angle with respect to said outgoing reference direction.

[0140] Preferably, said first movement device and said second movement device are configured to produce a relative displacement between said stacking surface and said outgoing orientation control device so as to maintain substantially constant a same deviation angle with respect to said outgoing reference direction for a variation in extension of said final tract preferably between 10% and 100%, more preferably between 20 and 90 %, even more preferably between 40 and 60 %, of a maximum length between a first constraint position and a second constraint position of said separator strip with respect to said stacking surface.

[0141] The Applicant has found that thanks to these features it is possible to maintain a constant angular orientation between the outgoing orientation control device and the stacking surface during the unwinding and / or stacking steps in such a way that the sail effect does not occur on the separator strip as the condition of angular variation prodromal to the creation of the asymmetrical conditions of lateral fluid- dynamic pressures on the separator strip is eliminated.

[0142] Preferably, said relative displacement occurs when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0143] In this case, the variation of the extension of the final tract of the separator strip occurs in a condition of substantial perpendicularity with respect to the reference direction in output of the separator strip from the outgoing orientation control device, thus making it possible to obtain a variation of a desired amount of separator strip that can be used, for example, to more effectively avoid dimensional encumbrance problems of other close kinematics.

[0144] According to other embodiments, said relative displacement occurs when said deviation angle is substantially equal to 0°.

[0145] Thanks to this technical solution, it is possible to unwind the separator strip while maintaining the same angular orientation given by the outgoing orientation control device, thus further reducing the damage and deformation that the separator strip may suffer.

[0146] Preferably, said method comprises arranging a first and / or a second release assembly of a sheet of metal foil configured to release a first or a second sheet of metal foil on a portion of said separator strip at said stacking surface upon an approaching movement between said first or second release assembly of a sheet of metal foil and said stacking surface to a minimum release distance with said separator strip.

[0147] Preferably, said method comprises Performing said approaching movement so as to produce a condition of substantially zero relative speed between said first and / or second release assembly of a sheet of metal foil and said stacking surface and having at least one displacement component parallel to said outgoing reference direction, preferably perpendicular to said stacking surface Preferably, such an approaching movement comprises a purely vertical displacement tract, more preferably a purely vertical displacement.

[0148] Preferably, said method comprises releasing on said portion of said separator strip at said stacking surface said first or second sheet of metal foil.

[0149] This makes it possible to optimise the release step of electrode sheet of metal foil by effectively controlling their release positions. Preferably, said method comprises releasing a first and second plurality of said first and second sheets of metal foils respectively by interposing between each of them a folded tract of a separator strip of said stacked structure. first and second sheet of metal foil respectively by interposing

[0150] Preferably, said method comprises reciprocally displacing said outgoing orientation control device and / or said stacking surface by defining a second distance between said outgoing orientation control device and said stacking surface.

[0151] Preferably, the mutual movement of said outgoing orientation control device and / or said stacking surface takes place iso as to reduce said second distance to the minimum when said deviation angle is comprised between +80° and -80°, and / or selectively extend said second distance when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0152] Thanks to this solution, the method that can be adopted confers greater freedom and adaptability or process modularity, allowing even the extension of the final tract of the separator strip to be varied without producing significant sail effect contributions, while maintaining a high process speed and guaranteeing constant separator strip tension.

[0153] Preferably, said method comprises the characteristic whereby when said deviation angle is comprised between +80° and -80° said second distance is substantially equal to said first distance.

[0154] This keeps the final tract of the separator strip as small and compact as possible when the strip has to vary its angular orientation significantly, so as to reduce or eliminate the sail effect that could potentially be generated.

[0155] Preferably, said method comprises the characteristic, wherein when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100° said second distance is comprised between 0% and 10% of a maximum length comprised between a first constraint position and a second constraint position of said separator strip with respect to said stacking surface.

[0156] In this way, it is possible to further vary the extension of the final tract, also according to specific formats of the stacked structure to be realised and / or to avoid possible interference of the kinematics provided in the apparatus.

[0157] Preferably, said method comprises arranging a movement unit comprising a first and / or second movement device configured to move said outgoing orientation control device and / or said stacking surface, respectively.

[0158] In this way, the desired movements are managed by means of a movement unit configured to be able to simultaneously act on a portion of the supply unit and / or a portion of the stacking unit in order to be able to optimise the relative displacements effectively and precisely.

[0159] Preferably, said method comprises arranging a first and / or a second release assembly of a sheet of metal foil configured to release a first or a second sheet of metal foil on a portion of said separator strip at said stacking surface upon an approaching movement between said first or second release assembly of a sheet of metal foil and said stacking surface to a minimum release distance with said separator strip.

[0160] Preferably, said method comprises Performing said approaching movement so as to produce a condition of substantially zero relative speed between said first and / or second release assembly of a sheet of metal foil and said stacking surface and having at least one displacement component parallel to said outgoing reference direction, preferably perpendicular to said stacking surface Preferably, such an approaching movement comprises a purely vertical displacement tract, more preferably a purely vertical displacement.

[0161] Preferably, said method comprises releasing on said portion of said separator strip at said stacking surface said first or second sheet of metal foil.

[0162] This makes it possible to optimise the release step of electrode sheet of metal foil by effectively controlling their release positions.

[0163] Preferably, said method comprises releasing a first and second plurality of said first and second sheets respectively by interposing between each of them a folded tract of separator strip of said stacked structure.

[0164] In this way, it is possible to optimise the creation of the stacked structure with the electrode sheets of metal foils interposed between the layers of separator strip by controlling the alignment of the electrodes in the release step in order to precisely and efficiently achieve the desired electrochemical cell.

[0165] Preferably, said method comprises realising said release of said first or second sheet of metal foil upon said approaching movement when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0166] In this way, the release occurs in a condition of substantial orthogonality between the outgoing reference direction and the stacking surface, which corresponds to the configuration in which the final tract of the separator strip is practically flush with the stacking surface and thus presents the ideal condition of flatness to receive the electrode sheets of metal foils.

[0167] This further optimises the release and transfer of the foils onto the separator strip in order to achieve the desired stacked structure.

[0168] Preferably, said method comprises relatively moving said first movement device and said second movement device to produce a relative displacement between said stacking surface and said outgoing orientation control device in such a way as to maintain substantially constant, for a variation in extension of said final tract of between 10% and 100%, more preferably between 20 % and 90 %, even more preferably between 40 % and 60 %, of a maximum length between a first constraint position and a second constraint position of said separator strip with respect to said stacking surface, a same deviation angle with respect to said outgoing reference direction.

[0169] The Applicant has found that thanks to these features it is possible to maintain a constant angular orientation between the outgoing orientation control device and the stacking surface during the unwinding and / or stacking steps in such a way that the sail effect does not occur on the separator strip as the condition of angular variation prodromal to the creation of the asymmetrical conditions of lateral fluiddynamic pressures on the separator strip is eliminated.

[0170] Preferably, said method comprises performing said relative displacement when said deviation angle is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0171] In this case, the variation of the extension of the final tract of the separator strip occurs in a condition of substantial perpendicularity with respect to the reference direction in output of the separator strip from the outgoing orientation control device, thus making it possible to obtain a variation of a desired amount of separator strip that can be used, for example, to more effectively avoid dimensional encumbrance problems of other close kinematics.

[0172] Preferably, said method comprises performing said relative displacement when said deviation angle is substantially equal to 0°.

[0173] Thanks to this technical solution, it is possible to unwind the separator strip while maintaining the same angular orientation given by the outgoing orientation control device, thus further reducing the damage and deformation that the separator strip may suffer.

[0174] Preferably, said method comprises configuring said second movement device of said stacking surface so as to move said stacking surface with a continuous movement along said second path which defines a closed curve.

[0175] Thanks to this technical solution, it is possible to realise a process that never includes stops, thus optimising the completion times of the stacked structure for the electrochemical cell while maintaining an ideal constant tension of the separator strip, and also avoiding any abrupt braking and acceleration of the various work units involved, which would thus suffer a significant reduction in the average service life.

[0176] Preferably, said method comprises configuring said first movement device as following according to at least one component to said second movement device when it displaces said stacking surface with a continuous movement.

[0177] Thanks to this technical solution, it is possible to envisage that the accumulation tract changes according to the movements of the stacking surface by providing a desired additional amount of separator strip to be used for displacements where the state of the art solutions necessarily involve stops.

[0178] It is significant to note that the examples of creation discussed above can be applied to any type of strip and not only to an insulating strip.

[0179] According to a further aspect of the present invention, the apparatus comprises an alignment device comprising a first frame including said outgoing orientation control device on which a first roller and a second roller are arranged, rotating about a first and a second longitudinal axis, respectively, which are housed so as to be placed side by side and spaced apart from each other so as to engage said separator strip between them along said predefined feed path.

[0180] Preferably, said first frame is rotatable about a rotation axis perpendicular to said first and second longitudinal axis.

[0181] Preferably, said rotation axis is substantially perpendicular to a first plane on which said first and second longitudinal axes lie.

[0182] In this way, a correction of the alignment of the strip can be produced by having the rotation axis of the alignment group parallel to the predefined feed path. Thus, it is possible to produce different inclinations of the strip with respect to its longitudinal development direction.

[0183] According to a further embodiment, said rotation axis is substantially parallel to a first plane on which said first and second longitudinal axes lie.

[0184] This allows a correction of the alignment of the strip to be produced by having the rotation axis of the alignment device perpendicular to the predefined feed path.

[0185] This angular variation in orientation of the strip may persist until an element further changes the actual orientation of the strip.

[0186] Preferably, said first frame is directly constrained to a second frame by means of a rotation member. Preferably said second frame is constrained to said first movement device.

[0187] This makes it possible to realise an effective compact form of the invention according to the present invention.

[0188] Preferably, said rotation device is configured to produce a relative angle of rotation of said first frame with respect to said first movement device of between 0° and 10°, more preferably between 0° and 5°, even more preferably between 0° and 1 °.

[0189] The Applicant noted that such preferred rotation intervals allow the strip to be displaced effectively without inducing damage or deformation.

[0190] According to one embodiment, the first roller or the second roller is connected at its axial ends to a first and a second sensor device, respectively. In other words, for each roller there is provided a pair of sensor devices, both of which are connected to the axial ends of either the first or second roller.

[0191] Preferably, said first and second sensor devices are housed within a support portion of said first frame to which the second roller is constrained with an allowed rotation along its second longitudinal axis.

[0192] According to one embodiment, each sensor device comprises a respective first and second annular load cell surrounding a first part of a connection body, which has a second part internally fixed to a rotoidal joint configured to allow the rotation about the second longitudinal axis.

[0193] Preferably, the rotoidal joint in turn is externally fixed to the second roller.

[0194] Thanks this technical solution it is possible to minimise the radial footprint of the rotoidal joint by limiting its contribution to interaction stresses between the second roller and the strip engaging it.

[0195] For the sake of completeness, it is reported that this embodiment can be similarly implemented on the first roller.

[0196] According to an embodiment, a first and / or a second load cell are housed externally to said support portion and on sides axially opposite to the first or second roller.

[0197] Preferably, said first and second load cells are of the compression type.

[0198] In one embodiment, said support portion comprises a first and a second support bracket at or in proximity to which the two axial ends of the second roller are constrained with an allowed rotation.

[0199] Preferably, said first and second load cells are respectively interposed between said first and second support bracket and said bracket.

[0200] In other words, said first and second support brackets are connected to the bracket by means of the first and second load cell.

[0201] Thus, when the second roller is subjected to a force transferred from the strip, it moves consistently in this direction. The two load cells detect this displacement and convert it into a signal that can be correlated to the force on the second roller.

[0202] Thanks to this solution, it is therefore possible to measure and control the evolution of the forces acting on the second roller.

[0203] Clearly, again, it is reported that this embodiment can be similarly implemented on the first roller. Furthermore, this technical solution becomes advantageously practical when, for example, one does not have the possibility of inserting load cells inside the roller one wishes to control.

[0204] According to one embodiment, the alignment device comprises at least one encoder (or similar transducer) configured to detect the rotations produced by an associated roller.

[0205] According to one embodiment, at least one encoder is mounted on an extension of the second frame or on said support portion preferably on the side axially opposite said first or second roller and at said first or second longitudinal axis.

[0206] Preferably, said at least one encoder is mounted at said first rotation axis, which being optionally motorised can provide further useful information on the displacement and tension applied to the strip.

[0207] Thanks to this device, it is possible to selectively detect the rotations of the first roller that may be induced by the motor element so that a more precise control of the actual strip feed can be achieved.

[0208] Preferably, said encoder is installed axially opposite the motor element in order to advantageously optimise the various space requirements.

[0209] In embodiments, the alignment device comprises said sensor for the alignment of the strip placed close to the first or second roller.

[0210] According to some embodiments, there are provided two sensors, one placed upstream and one downstream of the alignment device.

[0211] Preferably, both the sensor placed upstream of the alignment device and the sensor placed downstream of the alignment device are positioned at a respective distance from the first longitudinal axis of the first roller comprised between 50 and 15 mm, preferably about equal to 20 mm.

[0212] It is understood that the distance between the sensor placed upstream and the first longitudinal axis may differ from the distance between the sensor placed downstream and the first longitudinal axis, as long as both are within the range described above.

[0213] Preferably, the distance of such sensors with respect to the first longitudinal axis is measured from the most proximal portion of the sensor (or, alternatively, from its sensing element).

[0214] Preferably, the sensor placed downstream of the alignment device is positioned at a distance from the stacking surface of between 100 and 5 mm, preferably about equal to 10 mm.

[0215] According to one embodiment, the first roller is positioned so that its first longitudinal axis is at a distance of 150 to 50 mm from the stacking surface, preferably equal to 94 mm.

[0216] Preferably, said first and / or second rollers have a cylindrical development.

[0217] In said sense, said cylindrical development is a function of said first and / or second longitudinal axis.

[0218] This provides an advantageous and uniform feed and control of the strip, which is subjected to a controlled and reproducible gripping.

[0219] According to further embodiments, said first and / or second rollers have concave or convex development.

[0220] Thanks to this embodiment, the strip tends to move spontaneously towards the zone of maximum concavity or convexity.

[0221] According to further embodiments, one of said first and second rollers has concave development and the other has complementary convex development.

[0222] This creates an advantageous gripping between these rollers that spontaneously and effectively guides the strip towards the zone of maximum concavity.

[0223] According to embodiments, this zone of maximum concavity or convexity may be defined at a central longitudinal zone equidistant from the longitudinal ends of the first or second roller.

[0224] This make it possible to ensure that the strip is spontaneously moved towards the central longitudinal zone of the first or second roller, keeping it further away from the axial ends.

[0225] In embodiments, this zone of maximum concavity or convexity can be spaced from a central longitudinal zone of the first or second roller. Thanks to this asymmetrical configuration, the strip can be guided in an even more specific and particular way.

[0226] According to further embodiment, one of these first and second rollers has a conical development, i.e. tapered towards one of its longitudinal ends.

[0227] Thanks to this embodiment, the strip can be made to tend to move spontaneously according to the development of the tapering. For example, the strip may move spontaneously towards the zone of the roller that has a smaller diameter.

[0228] According to an embodiment of the present technical solution, the first and / or second movement device are configured to move respectively the outgoing orientation control device and / or the stacking surface in such a way as to move them reciprocally as following according to the outgoing reference direction by adapting their displacements each time also to the varying number of separator strip layers stacked on the stacking surface.

[0229] In other words, thanks to this technical solution, it is possible to finely adjust the displacements of the outgoing orientation control device and / or the stacking surface as the thickness of the stacked structure increases.

[0230] A possible mode of operation mentioned here purely by way of non-limiting example may involve displacing the outgoing orientation control device upwards (assuming, for example, that the stacked structure is increasing in thickness vertically) and / or displacing the stacking surface downwards consistently.

[0231] The characteristics and advantages of the invention will become clearer from the detailed description of a preferred embodiment thereof, shown by way of nonlimiting example, with reference to the appended drawings wherein:

[0232] • figure 1 is a schematic, frontal view of the apparatus according to the present invention;

[0233] • figures 2 to 5 are schematic front views illustrating the apparatus according to the present invention during different operating steps;

[0234] • figure 6 is a perspective view of an apparatus made in accordance with the present invention;

[0235] • figures 7 to 12 are schematic front views illustrating the apparatus according to the present invention during different operating steps;

[0236] • figure 13 is a schematic, frontal view of the detail of a stacked structure that can be realised using the apparatus according to the present invention,

[0237] • figures 14 to 18 each represent a schematic view of a detail of operating steps of the apparatus according to the present invention;

[0238] • figures 19a, 19b, 19c each represent a non-scaled schematic front view of details of operating steps of the apparatus according to the present invention,

[0239] • figure 20 is a perspective view of an optical element according to the present invention;

[0240] • figure 21 is a perspective view of a section according to plan XXI in figure 20,

[0241] • figures 22 and 23 are further detailed perspective views of components of the embodiment of the invention in figure 20,

[0242] • figure 24 is a further detail of an embodiment of the present finding

[0243] • figure 25 is a frontal perspective view of a detail of an alternative embodiment similar to that shown in figure 20,

[0244] • figure 26 is a sectional view of a further embodiment similar to that shown in figure 21 ,

[0245] • figures 27 and 28 are perspective views of further embodiments in accordance with this technical solution,

[0246] • figure 29 is a perspective view of a detail of the section shown in figure 21 relating to a further embodiment,

[0247] • figure 30 is a perspective view of a further embodiment according to this technical solution,

[0248] • figure 31 is a perspective view of a further embodiment according to this technical solution.

[0249] With reference initially to figures 1 and 2, a stacking apparatus 100 for stacking a separator strip NS and sheets of metal foils, realised in accordance with the present invention, is collectively referred to as 100.

[0250] In preferred embodiments, the apparatus 100 is intended to carry out the winding of a strip-shaped article NS intended for the production of electrochemical cells.

[0251] It is however understood that this represents a possible embodiment example and that the apparatus 100 according to the present invention may be intended for winding strip-shaped articles also intended for different uses, even in fields other than those relating to the production of electrochemical cells.

[0252] For example, again in the field of energy storage, the present invention may find application in the manufacture of other components intended for batteries or super-capacitors.

[0253] In some embodiments, such as the one illustrated in figure 1 , the apparatus 100 can be used as part of a production line for stacked structures S for electrochemical cells, in which the separator strip NS is stacked by folding on itself, thus realising an overlapping of layers and interposing electrode sheets of metal foils between the layers.

[0254] The separator strip NS is preferably a polymeric strip with, for example, the function of electrically insulating the electrode sheets of metal foils interposed between the different layers.

[0255] Depending on the embodiment, the separator strip NS can be both a monomaterial and a multilayer comprising a plurality of overlapping layers. An example of such materials used as a separator strip is polyethylene.

[0256] In further embodiments, the separator strip can be a generic strip, also made of metal material.

[0257] Now with reference to figure 11 , 201 and 301 identify two electrode sheets of metal foils, or more simply electrodes, which are placed on the separator strip NS during the stacking steps to create the stacked structure S and thus be able to proceed with the completion of the electrochemical cell.

[0258] Specifically, 201 identifies a cathode sheet of metal foil, while 301 identifies an anode sheet of metal foil. An example of materials adoptable as a cathode in the form of sheet of metal foil is aluminium, while an example of materials adoptable as an anode in the form of sheet of metal foil is copper.

[0259] In a general configuration, the apparatus 100, realised according to embodiments depicted in the accompanying drawings, comprises a supply unit 20, a stacking unit 1 , a movement unit 130 and a first and / or second release assembly of a sheet of metal foil 200, 300.

[0260] In preferred embodiments, the separator strip NS is supplied by a special dispensing device not shown in the figures. By way of example, such a separator strip NS dispensing device may consist of large coils in which the separator strip NS is collected in such a way that it is unwound and thus supplied during the operation of the apparatus on a continuous basis.

[0261] The separator strip NS supplied by the dispensing devices is then dispensed to the supply unit 20, which, in preferred embodiments, optimises the transfer and movement of the separator strip NS before it is stacked by the corresponding stacking unit 1 , the characteristics of which will be described in detail below.

[0262] According to preferred embodiments, the supply unit 20 comprises an input section, not shown in the figures, preferably capable of receiving the separator strip NS from the dispensing device, and an output section through which the separator strip NS transits out of the supply unit 20 and is fed to the stacking unit 1. The stacking unit 1 comprises a stacking surface 10 adapted to receive the separator strip NS so that it can be stacked.

[0263] A feed path PA of the separator strip NS is thus defined between the input and output section.

[0264] It will be appreciated that the strips NS, before being provided to the supply unit 20 can pass through further units for example intended to carry out preliminary processings on the strips. For example, the separator strip may be subjected to preliminary cleaning, laser ablation or surface activation in order to equalise its surface characteristics.

[0265] In preferred embodiments, the separator strip NS is continuously supplied into the supply unit 20.

[0266] In other words, the separator strip NS is fed into the supply unit 20 without ever stopping, proceeding at a speed greater than zero and preferably substantially constant.

[0267] In some specific cases, however, there may be a need to provide for interruptions in said continuous supply or to slow down feeding the separator strip NS for other operational requirements related to the specific processing being carried out.

[0268] According to some embodiments, it is possible to continue to unwind the separator strip NS at a constant speed without ever interrupting its supply and unwinding while keeping its kinematics in motion in order to reduce or avoid abrupt acceleration and deceleration of the movement devices while always ensuring a constant tension condition.

[0269] For said and other purposes, an accumulation device configured in such a way as to accumulate a quantity of said separator strip NS can be provided.

[0270] As illustrated in the example embodiments of figures 1 , 6, 11 and 12, the accumulation device included in the supply unit 20 may comprise a first orientation control device R1 included in the feed path PA, and positioned upstream, with respect to an unwinding direction of the separator strip NS, of the outgoing orientation control device R2 so as to identify at least one accumulation tract T of the separator strip NS between the first orientation control device R1 and the outgoing orientation control device R2.

[0271] According to preferred embodiments, the apparatus 100 comprises a movement unit 130 which in turn comprises a first movement device 131 .

[0272] According to embodiment examples shown in figures 11 and 12, the first movement device 131 is configured to displace said outgoing orientation control device R2 between an approached configuration CR, wherein the outgoing orientation control device R2 is at a minimum distance from said first orientation control device R1 , the minimum distance being measured according to the length of said separator strip NS comprised between the first orientation control device R1 and the outgoing orientation control device R2, and an extended configuration CE, wherein said outgoing orientation control device R2 is at a maximum distance from said first orientation control device R1 , said maximum distance being measured according to said length of said separator strip NS comprised between said first orientation control device R1 and said outgoing orientation control device R2.

[0273] The amount of stored strip can be variable, in that it can be provided that the amount of separator strip NS, in terms of length, that is stored is variable during the different steps of the process, in order to meet specific needs as mentioned above.

[0274] According to preferred embodiments, the movement unit 130 comprises a further movement device (not shown in the figures) configured to move said first orientation control device R1 in order to further determine the desired amount of separator strip NS included in the accumulation tract T.

[0275] Still with reference to figures 1 , 6, 11 , 12 and 20, it can be noted that the first orientation control device R1 is a preferably idle roller and that the outgoing orientation control device R2 comprises a first and a second roller 21 T, 212' placed side by side between which the separator strip NS is passed. As illustrated in the example in figure 6, in the accumulation tract T between the first orientation control device R1 and the outgoing orientation control device R2, there are further idle rollers constrained to fixed positions, which allow for controlled winding and guiding of the separator strip NS.

[0276] More preferably, the supply unit 20 comprises at least one voltage control device, preferably a dancer positioned at the accumulation tract T.

[0277] Still with reference to figure 1 , a schematic representation of the first movement device 131 can be noted, which may comprise, for example, horizontal guides, vertical guides or combinations thereof.

[0278] Still with reference to figure 1 , it is noted that said movement device 131 of said outgoing orientation control device R2 configured to displace said outgoing orientation control device R2 along a first working path P1 .

[0279] As shown in the examples depicted in figures 1 , 11 and 12, the first working path P1 is preferably a straight tract, more preferably perpendicular to the stacking surface 10 and even more preferably with a vertical orientation.

[0280] In fact, as shown in figures 1 1 and 12, it can be noted that the first and second rollers 211 ', 212' preferentially move in pure vertical translation according to said first working path P1 moving reversibly between the close configuration CR and the extended configuration CE. It is important to note that during these displacements the separator strip NS always maintains the same angular orientation along the accumulation tract T. In other words, although the first and second rollers 211 ', 212' move solidly along said T according to pure vertical translation, the orientation they impose on the separator strip NS remains unchanged, i.e. they do not produce variations in the inclination of the strip during these movements. This means that the separator strip NS in the accumulation tract is not subjected to asymmetrical conditions of fluid-dynamic lateral pressures and therefore does not suffer from the sail effect and related potential damage.

[0281] In this way, by varying the distance between the roller included in the first orientation control device R1 and the first and second roller 21 T, 212' included in the outgoing orientation control device R2, it will be possible to vary the length of the path that the separator strip has to travel, thus allowing the desired quantity to be accumulated. In this way, considering for example the embodiment explicated in figure 12, by lowering the first and second rollers 211 ', 212' the length of the separator strip NS included in the accumulation tract T may be increased and, considering a constant or substantially constant feed rate at the supply unit 20, the part of the strip downstream of the two rollers 211 ', 212' may be slowed down or stopped without producing a necessary stop of the feeding of the separator strip NS.

[0282] This solution will be further discussed in embodiments described in detail below.

[0283] It should also be noted that in preferred embodiments, the action of the first and second rollers 21 T, 212', or more generally of the outgoing orientation control device R2, can be associated with a retaining device (not shown in the figure) of the separator strip NS configured in such a way as to selectively control the feed of the separator strip NS.

[0284] For example, in some embodiments the presence of a gripper (not shown in the figure), or other similar retaining element, acting on the separator strip at the time when it is required to be controlled, retained or stopped may be provided in order to slow down the movement of such a part of separator strip NS.

[0285] The gripper can advantageously be movable, in such a way as to further adjust the feed rate of the relative strip by controlling its movement.

[0286] The gripper can also be associated with a relative knife which, if necessary, cuts the separator strip NS to be stacked, in order to create an interruption in the continuity of this strip within the stacked structure S. This can occur, for example, upon completion of the stacking step of the separator strip NS on the stacking surface 10.

[0287] It is also significant to note that the aforementioned rollers included in the first orientation control device R1 and in the outgoing orientation control device R2 allow the passing separator strip NS to be managed by giving it specific directions (depending on the reciprocal position of the rollers, their diameters, etc.) and thus effectively performing a control of the orientation that this separator strip NS assumes in space.

[0288] Now, with reference to figure 20, it can be noted that the alignment device 205' comprises a 21 O' translation unit which in turn comprises a first frame 215' and a second frame 216'. As can be noted, the first frame 215’ includes said outgoing orientation control device R2 on which the first roller 211 ' and the second roller 212' are arranged, respectively rotating about a first and a second longitudinal axis 211'X, 212'X, which are housed so as to be placed side by side to and spaced apart from each other so as to engage the separator strip NS between them along the predefined feed path PA.

[0289] The first and second rollers 21 T, 212' are preferably made of polymeric or metallic material.

[0290] It can be noted that the first frame 215' is translatable with respect to the supply unit 2 according to the translation direction DT having a component parallel to the first and second longitudinal axis 211 'X, 212'X.

[0291] With reference to figure 20, it can be seen how in this preferred embodiment, the translation direction DT is substantially parallel to the first and second longitudinal axes 211 'X, 212'X.

[0292] Furthermore, the second frame 216' is included in the first movement device 131 , which is configured to move according to the first working path P1 . In particular, the second frame 216' comprises a base 216a' provided with through holes adapted to allow the fixing by means of screws to a translating element of the first movement device 131. Preferably, this translating element is a combination of slide and rail or similar technical solutions.

[0293] Again, the second frame 216' comprises a main plate 216b' projecting perpendicularly from the base 216a'.

[0294] With reference to figures 22 and 23, it can be noted that on the main plate 216b' of the second frame 216', a rail 216c' of linear form is integrally constrained.

[0295] Such a rail preferably has an hourglass or "H" cross-section and is configured so that a slide 215c' can slide on it in a reversible manner.

[0296] Considering now figure 23, it can be seen that the rail 216c' and the slide 215c' cause the first frame 215' to be able to move relative to the second frame 216' according to a pure translation motion along the translation direction DT.

[0297] With reference to figure 21 , it can be noted that the first roller 21 T is operatively connected to a motor element 214a' so as to be actuatable in rotation about the first longitudinal axis 211'X.

[0298] Preferably, the motor element 214a' is a stepper or brushless electric motor and the first roller 21 T is directly coaxially connected to its drive shaft.

[0299] In this way it is possible to selectively actuate the first roller 21 T in rotation to decide how fast to feed the separator strip NS when present.

[0300] Still with reference to figure 21 , it can be noted that the second roller 212' is constrained to the first frame 215' by means of an idle joint or unidirectional joint 217' with an allowed idle rotation or rotation in one direction only about the second longitudinal axis 212X'.

[0301] The second roller 212' is constrained with an allowed rotation to a bracket 218b'. Said bracket 218b' is in turn constrained with an allowed translation to the first frame 215' and is configured to reversibly displace itself between a close position PR (depicted in figure 21 ), wherein the second roller 212' is at a minimum distance from the first roller 21 T, and a spaced-apart position PD (depicted, for example, in figure 20), wherein the second roller 212' is at a maximum distance from the first roller 21 T.

[0302] With reference to figure 20, it can be noted that the first and second rollers 21 T, 212' are spaced apar from each other, resulting in an interposed first opening 218a' that can vary depending on the position of the second roller 212'.

[0303] Preferably, this first opening 218a' is not equal to zero and is determined according to the thickness of the separator strip NS to be processed.

[0304] As shown in figure 21 , the bracket 218b' is moved so that the second roller reversibly translates between the close position and the spaced-apart position by means of an actuator 215b' constrained to it and driven in displacement by means of a further motor element 214b' which in the case depicted is an electric stepper motor (or, alternatively, brushless).

[0305] It is interesting to note that when the second roller 212' is in a position PD spaced apart from the first roller 21 T, it is easier to insert an initial end or head or appendage of the separator strip NS between them.

[0306] Once the initial end of the separator strip NS has passed downstream of the first and second rollers 21 T, 212', it is possible to move the second roller 212' to the close position PR by bringing both rollers 21 T, 212' into contact on the separator strip NS.

[0307] At this point the separator strip NS is effectively engaged between the two rollers 21 T, 212' and a translation of them in the translation direction DT immediately results in a consistent translation of the portion of separator strip NS engaged therein.

[0308] Even more, once the separator strip NS is engaged between the first and second roller 21 T, 212' it will be possible to effectively advance it selectively by rotating the electric stepper or brushless motor 214' connected to the first roller 21 T.

[0309] It is considered useful to emphasise, for completeness of argument and with reference to the example in figure 24, how the alignment device 205' is configured to displace the separator strip NS so as to align a portion of reference 81 a of the separator strip NS with respect to a reference 81 b of the apparatus 100. According to preferred embodiments, the reference portion 81 a is, for example, advantageously a side edge of the separator strip NS.

[0310] Preferably and again with reference to figure 24, it can be noted that reference 81 b is a spatial point identified at a sensor 260'. Preferably, the sensor 260' can be an optical sensor, a photo / video camera, or similar technical solution.

[0311] Furthermore, the set reference can be a point, or a spatial segment or other specifically predefined geometric elements.

[0312] The sensor 260' is configured to detect any difference in alignment AAII between the separator strip NS and the predefined feed path PA. In particular, in line with what has been argued above, it is advantageous to determine this difference in alignment by noting any variation in distance between the portion of reference 81a and reference 81 b.

[0313] Therefore, the alignment device 205' is configured to include a sensor 260' to identify any alignment difference AAII between the separator strip NS and the predefined feed path PA, and in the event that the alignment difference AAII is other than zero, to displace the outgoing orientation control device R2 to align the separator strip NS to the feed path PA.

[0314] It is important to note that thanks to the claimed technical solution, the alignment of the separator strip NS can be carried out while the alignment device 205' (and thus also the outgoing orientation control device R2) are moved along the first working path P1 , allowing a continuous dispensing of the separator strip NS to be maintained.

[0315] Preferably, the apparatus 100 comprises a processing unit (not shown in the figures) operatively connected to the sensor 260' and configured to process the data collected by the sensor 260' and to identify a correction for any misalignment between an actual feed path of said separator strip NS and the predefined feed path PA.

[0316] Furthermore, the processing unit is operatively connected to different types of the alignment devices or groups according to the present invention and configured to send instructions to the latter to realise a desired alignment correction movement. This makes it possible to produce the necessary alignment in an automated, fast and efficient manner.

[0317] According to some embodiments, there are provided two sensors, one upstream and one downstream of the 205' alignment device.

[0318] Preferably, both the sensor placed upstream of the alignment device 205' and the sensor placed downstream of the alignment device 205' are positioned at a respective distance from the first longitudinal axis 211X' of the first roller 21 T comprised between 50 and 15 mm, preferably about equal to 20 mm.

[0319] It is understood that the distance between the sensor placed upstream and the first longitudinal axis 211X’ may differ from the distance between the sensor placed downstream and the first longitudinal axis 211 X', as long as both are within the interval described above.

[0320] Preferably, the distance of such sensors from the first longitudinal axis 211X' is measured from the most proximal portion of the sensor (or, alternatively, from its sensing element).

[0321] Preferably, the sensor placed downstream of the alignment device 205’ is positioned at a distance from the stacking surface of between 100 and 5 mm, preferably about equal to 10 mm.

[0322] According to one embodiment, the first roller 211 ' is positioned so that its first longitudinal axis 211 X' is at a distance of 150 to 50 mm from the stacking surface, preferably 94 mm.

[0323] According to an embodiment shown in figure 31 instead of two sensors, three sensors are provided respectively, of which the first sensor 260a' is placed upstream of the alignment device 205' and the second and third sensors 260b', 260c' downstream of the alignment device 205'. More particularly, the second sensor 260b' is positioned so that it is at a distance from the first longitudinal axis 211X' of the first roller 211 ' of between 50 and 15 mm, preferably about equal to 20 mm, while the third sensor 260c' is positioned so that it is at a distance from the second longitudinal axis 212X' of the second roller 212' of between 50 and 15 mm, preferably about equal to 20 mm.

[0324] Similarly, the above considerations for the sensor downstream of the alignment device with respect to the stacking surface also apply to the second and third sensors 260b', 260c'. figure 25 shows a further possible embodiment in which the first and second rollers 211 ', 212' have concave and convex development.

[0325] In more detail, it can be noted that the two rollers 211 ', 212' are shaped in such a way that they are substantially complementary and effectively engage the separator strip NS between them.

[0326] According to the embodiments shown, the first roller 211 ' has a substantially convex development along its longitudinal axis 211 X' while the second roller 212' preferably has a concave development.

[0327] In a further embodiment shown for illustrative and non-limiting purposes in figure 26, the first roller 211 ' (or, similarly, the second roller 212') can have a conical development with respect to its longitudinal axis. As can be noted, the first roller 211 ' has a tapered development from one axial end towards the other. It is also possible to realise a combination of the first and second rollers 21 T, 212' having a conical development and configured as complementary between them, i.e. with tapering oriented from opposite directions with reference to the respective longitudinal axes.

[0328] In preferred embodiments, the roller included in the first orientation control device R1 is preferably mounted on a dancer, or similar technical solution, which allows the orientation of the separator strip NS to be changed by tilting or moving the rotation axis of the roller.

[0329] With reference to now to figures 1 to 12, the stacking unit 1 is arranged immediately downstream of the supply unit 20 in such a way as to receive the separator strip NS moved by it.

[0330] Preferably, the separator strip NS is supplied by being displaced along a supply direction while the outgoing orientation control device R2 is in charge of giving an outgoing reference direction DRU (i.e. a final angular orientation) that the separator strip NS would assume if it could freely continue its imposed motion and the constraints and kinematics placed downstream of said outgoing orientation control device R2 did not intervene.

[0331] As can be noted for example from figures 3, 6 and 8, the outgoing reference direction DRU is preferably vertical.

[0332] In the example shown in figure 9, the outgoing reference direction DRU imposed on the separator strip NS by the two rollers 211 ', 212' is substantially horizontal. For greater convenience and clarity, an orientation angle a is defined, which defines the angle that the outgoing reference direction DRU determines with respect to the vertical of the room in which the apparatus 100 is installed.

[0333] In this sense, it can be clearly understood how the configuration of the separator strip NS with respect to the outgoing orientation control device R2 results in a vertical outgoing reference direction DRU and a consequent orientation angle value a equal to 0°, for example in the embodiment shown in figure 5, while figure 9 shows a embodiment relative to a horizontal outgoing reference direction DRU and a relative orientation angle value a equal to 90°.

[0334] With reference to, for example, to figure 1 or 2, TF identifies an end section of said separator strip NS defined downstream of said outgoing orientation control device R2 and upstream of a first constraint position PV1 or a second constraint position PV2 of said separator strip NS with respect to said stacking surface 10. It can be noted that, according to preferred embodiments shown in figures 11 and 12, the first constraint position PV1 corresponds to a point of intervention of a first clamping device 51 , while the second constraint position PV2 corresponds to a point of intervention of a second clamping device 52 included in the stacking unit 1 and acting at the stacking surface 10. More precisely and now with reference to figure 12 only, the first clamping device 51 is the device placed in a distal position with respect to said outgoing orientation control device R2, while the second clamping device 52 is placed in a close position with respect to said outgoing orientation control device R2.

[0335] According to preferred embodiments, the first and / or second clamping devices 51 , 52 are grippers or suction cups or electromagnetic systems adapted to selectively retain a portion of the separator strip NS in a manner integral with the stacking surface 10.

[0336] According to embodiments, the stacking surface 10 has a substantially planar development with a substantially rectangular base. It can be dimensioned according to the desired format of stacked structure S to be created.

[0337] Again, the relative positions of the first and / or second clamping device 51 , 52 can also be defined or changed depending on the format of stacked structure S to be created. In other words, the first and / or second clamping device 51 , 52 are constrained with an allowed coplanar and / or perpendicular translation with respect to the stacking surface 10.

[0338] According to some embodiments, shown by way of example in figure 11 , the stacking unit 1 comprises a plurality of clamping devices 51 , 52.

[0339] Still with reference to figure 11 , it can be noted that the separator strip NS is constrained by the second clamping device 52. In this condition, the final tract TF is defined downstream of the outgoing orientation control device R2 and the second clamping device 52.

[0340] It can be clearly seen that, at the moment when the first clamping device 51 is activated, the final tract TF changes its extension and its deviation angle [3.

[0341] This is because it is now the first clamping device 51 that defines the extension and angular orientation of the final tract TF.

[0342] In general, the activation of a clamping system, which produces the creation of a removable constraint of the separator strip NS at the stacking surface 10, interposed between the outgoing orientation control device R2, placed upstream, and a clamping device placed further downstream, always results in a variation of the extension of the final tract and in some cases a variation of the relative deviation angle [3.

[0343] According to what has been discussed above and as shown for example in figures 11 and 12, it can be noted that the extension and orientation of the final tract TF can vary significantly and rapidly depending on whether or not a clamping device is engaged on the separator strip NS. It is in fact evident that when a gripper acts on a section of separator strip NS by constraining it solidly to the stacking surface 10, this portion does not undergo any further displacements relative to the stacking surface but moves rigidly with it as if defining a single body. In this sense, therefore, it seems appropriate to grasp how the part of the separator strip NS not yet constrained to the stacking surface 10 and placed downstream of the outgoing orientation control device R2 is identified as the aforementioned final tract TF and characterised by the possibility of varying significantly in extension and spatial orientation before being further constrained and behaving in a manner integral to said stacking surface 10.

[0344] Preferably and with reference, for example, to figures 3, 5 and 8, embodiments are shown in which said final tract TF is oriented according to a deviation direction DD, identifiable downstream of said outgoing orientation control device R2, and defining a deviation angle [3 with respect to said outgoing reference direction DRU.

[0345] Again, as can further be noted from figures 3, 5 and 8, the deviation angle [3 can vary from approximately +100° to -100° with respect to the outgoing reference direction DRU.

[0346] Thanks to this angular variation of the final tract TF, it is possible to stack it on the stacking surface 10 by first folding it in one direction and then in the opposite direction, thus creating a sequence of continuous, overlapping layers as shown in figure 13.

[0347] With reference to figure 13, it can be noted that the two clamping devices 51 , 52 acting respectively at the first and second constraint position PV1 , PV2 can act on the portion of the separator strip NS to be constrained simultaneously or at different times. According to preferred embodiments, the clamping device concerned is actuated by clamping the new layer of separator strip NS as soon as it is substantially brought to abut on the stacking surface 10 or on an underlying layer of the stacked structure S, when in the process of completion.

[0348] With reference to figure 6, it is interesting to note that said outgoing reference direction DRU corresponds to the longitudinal axis of a Pll output plane coplanar to said separator strip NS at said outgoing orientation control device R2.

[0349] According to one embodiment, said apparatus 100 comprises the movement unit 130 comprising the first and / or a second movement device 131 , 132 which are / is configured to move respectively said outgoing orientation control device R2 and / or said stacking surface 10 so as to mutually displace them as following according to said outgoing reference direction DRU, so as to maintain said deviation angle [3 greater than ±60°, more preferably ±70°, even more preferably ±80° when said end tract TF has an extension greater than 1 / 3 of a maximum length comprised between said first constraint position PV1 and said second constraint position PV2 of said separator strip NS with respect to said stacking surface 10. Preferably, said maximum length is measured in a direction perpendicular to said PU exit plane.

[0350] Indeed, it can be noted that, considering what is shown in figures 1 , 2, 6, 11 and 12, the first movement device 131 moves said outgoing orientation control device R2 as following with respect to the movements produced by the stacking surface 10 by the second movement device 132. Preferably, the second movement device 132 may comprise, for example, horizontal or vertical guides or combinations thereof.

[0351] According to preferred embodiments, this displacement produced by the movement device 131 is configured to be a pure vertical translation. Since the first and second movement devices 131 , 132 are configured to be in mutual pursuit this implies that the second movement device 132 will also move the stacking surface 10 by the same amount as the vertical translation achieved by the outgoing orientation control device R2.

[0352] With reference to for example to figures 1 and 2, it can be noted that the displacement of the stacking surface 10 produced by the second movement device 132 defines the second working path P2, which corresponds to a closed path of complex shape, e.g. bilobed or elongated jib-shaped, comprising both horizontal and vertical displacement components, said second working path P2 being however configured to displace in a manner consistent with the first working path P1 of the outgoing orientation control device R2.

[0353] In other words, the second working path P2 is configured to include a vertical translation component substantially equal in extension and simultaneous to the pure vertical translation realised by the outgoing orientation control device R2 according to the first working path P1. This pure vertical translation component included in the first and second working paths P1 , P2 is identified in figure 2 as V1.

[0354] This implies that while the stacking surface 10 is displaced vertically consistently with the outgoing orientation control R2, its further displacement according to a horizontal component is realised.

[0355] In this way, it is possible to produce a rapid horizontal displacement of the stacking surface 10 by varying the deviation angle [3 at high speed, thus bringing into short displacement along said second working path P2 an extensive amount of the final tract TF of the separator strip NS approaching the stacking surface 10, in order to achieve the abutment condition between the final tract TF and the stacking surface 10 about a value of the deviation angle [3 equal to about +90° or -90°.

[0356] In other words and with reference now to figure 7, said movement unit 130 is configured to relatively displace said outgoing orientation control device R2 with respect to said stacking surface 10 so as to maintain a first distance D1 therebetween, measured according to said outgoing reference direction DRU, substantially constant while said stacked structure of said separator strip NS is being produced and comprised between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm.

[0357] As can be noted, for example, from figures 1 , 6 and 14, and as described above, the first distance D1 , preferably measured in the vertical direction, is always kept below a limit value comprised between 0 and 30 mm and, subject to the kinematic motion involved, as constant as possible.

[0358] It can be seen that this value can be maintained even when the stacking surface 10 is displaced horizontally by amounts greater than 30 mm, since what is binding is the distance according to the vertical component alone. According to preferred embodiments and with reference to figure 8 and even more so to figure 10, it can be noted that, for values of the deviation angle [3 which are close to, for example, +90° or -90°, the first movement device 131 and said second movement device 132 are configured to produce a relative displacement SR between said stacking surface 10 and said outgoing orientation control device R2 so as to maintain substantially constant a same deviation angle [3 with respect to said outgoing reference direction DRU for a variation of extension of said final tract TF preferably between 10 and 100%, more preferably between 20% and 90%, even more preferably between 40 and 60% of a maximum length between a first constraint position PV1 and a second constraint position PV2 of said separator strip NS with respect to said stacking surface 10, so as to minimize the amount of surface of said separator strip NS exposed to variations in lateral fluiddynamic pressures as a function of angular variations of unwinding of said separator strip NS during the creation of a stacked structure of said separator strip NS.

[0359] It is in fact clear that when the stacking surface 10 is displaced according to the second working path P2 at a deviation angle [3 equal to 85° ± 10%, for example moving away from the outgoing orientation control device R2, the configuration imposes to keep the outgoing orientation control device R2 as following according to at least one component to the stacking surface 10, i.e., to keep the first distance D1 substantially constant, causing the relative displacement of the stacking surface 10 with respect to the outgoing orientation control device R2 to be substantially horizontal according to a deviation angle [3 substantially equal to +90° or -90°, thereby, in such a case, preventing the sail effect from forming on the final tract TF of the separator strip NS.

[0360] According to embodiments shown for example in figure 15, when said deviation angle [3 is substantially equal to +90° or -90°, said first distance D1 varies

[0361] • when approaching said stacking surface, from said constant value by a value comprised between said first distance and 200% of said first distance, or

[0362] • when moving away from said stacking surface, from said constant value to a value comprised between said first distance and 200% of said first distance.

[0363] In this way, it is, for example, possible to further increase the value of the deviation angle [3 by causing the separator strip NS to be brought into contact with said stacking surface 10 more effectively and reducing the possibility of creases forming on the surface of the separator strip NS while it is being constrained by the first and / or second clamping device 51 , 52.

[0364] With reference to figures 19a, 19b, 19c, some moments are shown in detail regarding the changes in the first distance D1 as the outgoing orientation control device R2 and the stacking surface 10 move in mutual approach. In the example shown, the first direction D1 is measured along the vertical axis Z. In more detail, figure 19a schematically shows a condition where the first distance D1 is equal to 10mm and the approaching displacement begins. For the sake of simplicity and purely for illustrative purposes, we consider a case in which the outgoing orientation control device R2 is substantially stationary while the stacking surface 10 is displaced in approach along the outgoing reference direction DRU, i.e. upwards, figure 19b shows that the stacking surface 10 has reached the height of the outgoing orientation control device R2 and the first distance D1 has become substantially zero, figure 19c shows the moment when the stacking surface 10 continues the movement in progress in figure 19b maintaining the same direction and direction by adding a further value of upward vertical displacement equal in modulus to the initial value of the first distance D1. In this configuration, the deviation angle [3 is substantially equal to 110°.

[0365] With reference to figure 2, said movement unit 130 is configured to displace said outgoing orientation control device R2 relative to said stacking surface 10 by defining a second distance D2 between said outgoing orientation control device R2 and said stacking surface 10 so as to:

[0366] - Reduce said second distance D2 to the minimum when said deviation angle [3 is comprised between +80° and -80°, and / or

[0367] - Selectively extend said second distance D2 when said deviation angle [3 is comprised between + 81 ° and +100° or - 81 ° and -100°.

[0368] Still with reference to figure 2, it is noted that the second distance D2 is identified as the minimum distance existing between any portion of said outgoing orientation control device R2 and any portion of the stacking surface 10.

[0369] It can thus be clearly grasped that the second distance D2 can preferably be substantially equal to said first distance D1 when said deviation angle [3 is comprised between +80° and -80°, thus fulfilling the condition for the first distance D1 between 0 mm and 30 mm.

[0370] Furthermore, according to preferred embodiments, when said deviation angle [3 is comprised between + 81 ° and +100° or - 81 ° and -100° said second distance D2 is comprised between 0% and 70% of the maximum length between said first constraint position PV1 and said second constraint position PV2.

[0371] Alternatively, according to other preferred embodiments, when said deviation angle [3 is comprised between + 81 ° and +100° or - 81 ° and -100° said second distance D2 is comprised between 0% and 10% of a maximum length between said first constraint position PV1 and said second constraint position PV2.

[0372] According to the embodiments shown for example in figures 11 , 16 and 17, the apparatus preferably comprises a first and a second release assembly of a sheet of metal foil 200, 300, configured with respect to said second movement device 132 to release, at a minimum release distance DmR from said stacking surface 10 on a portion of said separator strip NS at said stacking surface 10, a first and / or second sheet of metal foil 201 , 301 upon an approaching movement Mac of said first and / or second release assembly of a sheet of metal foil 200, 300 with respect to said stacking surface 10 during a receiving tract TR of said second working path P2, said approaching movement Mac being configured so as to produce a condition of substantially zero relative speed between said first and / or a second release assembly of a sheet of metal foil 200, 300 and said stacking surface 10, and having at least one displacement component parallel to said outgoing reference direction DRU, preferably perpendicular to said stacking surface 10, more preferably vertical.

[0373] According to embodiments, said first and / or second release assemblies of a sheet of metal foil 200, 300 comprise corresponding first and / or second displacement devices 210, 310 configured to selectively displace said first and / or second release assemblies of a sheet of metal foil 200, 300 according to said approaching movement Mac.

[0374] Preferably, said first and / or second displacement device 210, 310 are kinematics with two degrees of freedom, plus preferably a composition of a horizontal guide and a vertical guide.

[0375] According to preferred embodiments shown in figures 16 and 17, the approaching movement Mac substantially begins when the first orientation control device R1 and the outgoing orientation control device R2 are in the close configuration CR, while the approaching movement Mac substantially ends when the first orientation control device R1 and the outgoing orientation control device R2 are in the extended configuration CE.

[0376] With specific reference now to figures 2 and 17 and considering a preferred embodiment, it is noted that such a general configuration implies that while the outgoing orientation control device R2 translates vertically displacing away from the first orientation control device R1 of purely vertical motion V1 moving from the close configuration CR to the extended configuration CE, the stacking surface 10 and the second release assembly of a sheet of metal foil 300 perform a movement having the same vertical component V1 so as to realise at this process step a condition of consistent or integral movement substantially identical for the vertical component between the three different devices.

[0377] This fine concerted mechanism ensures that the release of the second sheet of metal foil 301 occurs with a minimum of inducible damage on the stacked structure S being made, with a minimum of sail effect given by the guaranteed condition of first distance D1 between 0 mm and 30 mm, with a constant tension of the separator strip NS guaranteed by the possibility of selectively determining the accumulation tract T and realising a continuous motion of the stacking surface 10 permitted by the fact that while the release of the first or second sheet of metal foil 201 , 301 takes place, the whole system translates vertically, displacing from the close to the extended configuration.

[0378] This concerted mechanism also occurs similarly when the release of the first sheet of metal foil 201 by the release assembly of a sheet of metal foil 300 is realised.

[0379] Preferably, and with reference to figure 11 , said first and second release assemblies of a sheet of metal foil 200, 300 respectively comprise a first or second retaining device 230, 330 configured to selectively retain the first or second sheet of metal foil 201 , 301 , for example before and during the approaching movement Mac, and to release the first or second sheet of metal foil 201 , 301 , by deactivating said first or second retaining device 230, 330 for example at the end of the approaching movement Mac.

[0380] These first and second retaining devices 230, 330 are vacuum systems such as suction cups.

[0381] According to one embodiment, said second movement device 132 is configured to displace said stacking surface 10 along said receiving tract TR of said second working path P2 so as to approach it with respect to said first and / or second displacement device 210, 310 during said approaching movement Mac.

[0382] Thanks this technical solution it is possible to reduce the approaching time and increases the relative speed when approaching between stacking surface 10 and the first or second release assembly of a sheet of metal foil 200, 300.

[0383] According to a further embodiment, said second movement device 132 is configured to displace said stacking surface 10 along said receiving tract TR of said second working path P2 so as to displace it away from said first and / or second movement device 210, 310) during said approaching movement Mac, said approaching being performed by means of a difference in the displacement speed between said stacking surface 10 and said first or second release assembly of a sheet of metal foil 200, 300.

[0384] In this way, an approach between the stacking surface 10 and the first or second release assembly of a sheet of metal foil 200, 300 can be realised, allowing a less abrupt or sudden release to take place.

[0385] The present invention also relates to an implementation of a method 500 for creating the stacked structure S of a separator strip NS, preferably for an electrochemical cell intended for producing batteries.

[0386] Said method 500 comprises arranging an apparatus 100 comprising a fixed frame on which the supply unit 20, the movement unit 130, the stacking unit 1 and the first and second electrode release assemblies 200, 300 are constrained.

[0387] As described above, the movement unit 130 preferably comprises a vertical guide 131 allowing pure vertical movement of the first and second rollers 21 T, 212' placed side by side and counter-rotating, and a combined horizontal and vertical guide 132 allowing complex displacement in space discussed in more detail below. According to alternative embodiments, the outgoing orientation control R2 comprises four rollers.

[0388] The stacking surface 10 is mounted on an equipment integrally constrained to the combined horizontal and vertical guide 132.

[0389] The vertical guide 131 and the combined horizontal and vertical guide 132 are mounted on the fixed frame of the apparatus 100 and guided by means of motorisation.

[0390] Downstream of the dispensing zone (not shown in the figures) the separator strip NS passes through the supply unit 20. In more detail and with reference to figures 1 , 16 and 17, the separator strip NS passes through the accumulation tract T, included in the supply unit 20, defined between the accompanying roller R1 and the first and second rollers 21 T, 212' located at the exit of the accumulation tract T itself.

[0391] Downstream of the first and second rollers 211 ', 212' the conveyor belt is permanently constrained to the stacking surface 10 by the gripper 52.

[0392] In alternative embodiments (not shown in full in the figures), all movements implemented with motorised systems can alternatively be implemented with pneumatic or electric systems (and vice versa).

[0393] It is interesting to note that when the second roller 212' is in a position PD spaced apart from the first roller 211 ', it is easier to insert an initial end or head of the separator strip NS between them.

[0394] Preferably, once the initial end of the separator strip NS has passed downstream of the first and second rollers 211 ', 212' while they were arranged according to the spaced-apart position PD, it is possible to move the second roller 212' to the close position PR by bringing both rollers 21 T, 212' into contact on the separator strip NS.

[0395] At this point the separator strip NS is effectively engaged between the two gripping rollers 211 ', 212' and their translation, according to the translation direction DT, or their rotation immediately results in a consistent displacement of the portion of separator strip NS engaged there.

[0396] Even more, once the separator strip NS is engaged between the first and second roller 211 ', 212' it will be possible to effectively advance it selectively by rotating the electric stepper or brushless motor 214a' connected to the first roller 211 '.

[0397] With reference to figure 30, it can be noted that the alignment device 205' comprises a linear transducer 228c' configured to detect the linear displacements and speed of the first frame 215' along the translation direction DT.

[0398] In more detail, the linear transducer 228c' comprises a sensing element (sensor) 228c1 ' configured to detect a physical displacement and a measuring slider 228c2' configured to follow the movement of the measured object and transmit the change to the sensing element.

[0399] In the embodiment shown in figure 30, the sensor 228c1 ' is mounted on the second fixed frame 216', while the slider 228c2' is mounted on the first movable frame 215'.

[0400] Now with reference to figures 27 and 28, it can be noted that a first and a second load cell 218c', 218d' can be mounted on the bracket 218b'. These first and second load cells 218c', 218d' are of the compression type and housed on axial ends opposite with respect to the second longitudinal axis 212X' of the second roller 212'.

[0401] In addition, the first and second load cells 218c', 218d' are respectively interposed between a first and second support bracket, on which the second roller 212' with an allowed rotation is housed, and the bracket 218b'. As will be seen below as a function of further embodiments, these support brackets are included in a support portion 215d' for the second roller 212'.

[0402] In this way, when the second roller 212' is subjected to a force transferred by the separator strip NS moves consistently in that direction and the two load cells 218c', 218d' detect this displacement by converting it into a signal that can be correlated to the force applied.

[0403] Furthermore, these load cells are configured in such a way as to be able to detect, in addition to tension variations induced by the separator strip NS, useful information so that an operatively connected processing unit can modify the position of the bracket 218b' so as to bring the second roller 212' closer to or further away from the first gripping roller 21 T, thereby optimising the clamping force exerted on the separator strip NS by the two rollers 21 T, 212'. figure 29 shows a detailed axial section of an embodiment in which the second roller 212' is connected at its axial ends to a first and a second sensor device 1001 , 1002 respectively, which are preferably housed within the support portion 215d' to which the second roller 212' is constrained with an allowed rotation about its own second longitudinal axis 212X'.

[0404] This support portion 215d' preferably comprises the first and second support brackets described above and which are configured to accommodate the respective ends of the second roller 212'. Returning to what is shown in figure 29, each sensor device 1001 , 1002 comprises in turn a respective first and second annular load cell 1001a, 1002a surrounding a first part 601 of a connection body 600, which has a second part 602 internally fixed to a rotoidal joint 610 configured to allow the rotation about the second longitudinal axis 212X'.

[0405] This rotary joint 610 in turn is externally fixed to the second roller 212'. In particular, this configuration advantageously minimises the radial footprint of the rotoidal joint 610 by limiting its contribution to interaction stresses between the second roller 212' and the separator strip NS engaging it.

[0406] The embodiments shown for the first and / or second roller 21 T, 212' can advantageously be applied to any roller included in the apparatus described herein.

[0407] As shown in figure 30, in some embodiments the alignment device 205' includes at least one encoder 211 a' (or similar transducer) configured to detect the rotations produced by a roller associated therewith.

[0408] According to an embodiment, the encoder 21 1 a' is mounted on an extension of the second frame 216' or on the support portion 215d' preferably on the side axially opposite said first or second roller 21 T, 212' at the first or second longitudinal axis 211X', 212X'.

[0409] According to an embodiment shown for example in figure 30, at least one encoder 211 a' is mounted at the first rotation axis 211X' which, being optionally motorised, can provide further useful information on the displacement and tension applied to the separator strip NS.

[0410] Thanks to such a device, it is possible to selectively detect the rotations of the first roller 211 ' that are induced by the motor element 214a' so that a more precise control of the actual feed of the separator strip NS can be achieved. In particular, the measurement of the rotations of the first roller 21 T about its first longitudinal axis 211X' by means of the encoder 211 a' is significantly advantageous immediately after a new end of the separator strip NS has been interposed between the first roller 21 T and the second roller 212' and the first roller 21 T has been brought closer to the second roller 212' bringing them to the close position PR.

[0411] At this point it is possible to feed by rotation of the motor element 214a' the free end of the separator strip NS (not yet engaged on the stacking surface) in contact with the first roller 21 T knowing, thanks to the information provided by the encoder 211 a', by how much and with what speed the end of the separator strip NS is displacing itself.

[0412] It can be noted from figure 30 that the encoder 211 a' is installed on the side axially opposite to the motor element 214a', so that the various overall dimensions required can be optimised advantageously. In embodiments, a portion integral with the roller (e.g. its shaft) extends longitudinally beyond the first roller 211 ' so that its rotations can be measured by the encoder 211 a'.

[0413] For further clarity and completeness of description, an example of a sequence of operations carried out by apparatus 100 according to method 500 in order to create the stacked structure S is shown in Table 1 below.

[0414] Table 1. Example of a sequence of main operations for creating the stacked structure S.

[0415] With reference to Table 1 and figure 18, it can be noted that in step 1 , the final tract TF of the separator strip NS is oriented according to a deviation angle [3 equal to 0°.

[0416] The final tract TF is measured just downstream of the last contact point between the roller R2b and the separator strip NS and just upstream of the contact point between the first gripper 52 and the separator strip NS.

[0417] The final tract is approximately 12 mm long. The first distance D1 is equal to 7 mm and the second distance D2 is equal to the first distance D1 . figure 18 again shows the second closed working path P2 realised by the combined horizontal and vertical guide 132 showing its substantially bilobed shape (similar to the infinity symbol placed horizontally) with the lateral tracts substantially straight and vertical (as can be noted from the parallelism between these portions of the second working path P2 and the vector triplet shown in which Z represents the vertical axis).

[0418] It is interesting to note that according to an embodiment of the present technical solution, the first and / or the second movement device 131 , 132 are configured to respectively move the outgoing orientation control device R2 and / or the stacking surface 10 in such a way as to move them reciprocally as following according to the outgoing reference direction DRU by adapting their displacements each time also to the varying number of layers of separator strip NS stacked on the stacking surface 10.

[0419] In other words, thanks to this technical solution, it is possible to finely adjust the displacements of the outgoing orientation control R2 and / or the stacking surface 10 as the thickness of the stacked structure increases.

[0420] A possible mode of operation mentioned here purely by way of non-limiting example may involve displacing the outgoing orientation control device R2 upwards (assuming, for example, that the stacked structure is increasing in thickness vertically) and / or displacing the stacking surface 10 downwards consistently.

[0421] Again, in step 1 the accompanying roller R1 and the two counter-rotating facing rollers 21 T, 212' are in the extended configuration CE. The accumulation tract T is measured, according to the length of the separator strip NS, from the horizontal diameter of the accompanying roller R1 to the horizontal diameter of the two counter-rotating facing rollers 21 T, 212'.

[0422] In step 2, with reference to figure 18, the stacking surface 10 is moved simultaneously to the right (corresponding to an increment in the Y-position coordinate) and upwards (corresponding to an increment in the Z-position coordinate). The separator strip NS is still retained by the second gripper 52 (see e.g. figure 5).

[0423] Simultaneously, the first and second rollers 211 ', 212' side-by-side counterrotating rise vertically (corresponding to an increase in the Z-coordinate position) being displaced by the vertical guide 131 from the extended configuration CE to the close configuration CR.

[0424] As can be noted from figure 18 and Table 1 , the deviation angle [3 increases from 0° to 90°.

[0425] In figures 1 -5 and 7-18 shown, the representation is two-dimensional in the YZ plane.

[0426] In this discussion, therefore, conditions in which the change in position along X will be significant will not be made explicit.

[0427] Again, with reference to figure 6, it can be seen that displacements along the axis X of the separator strip NS and therefore of the output plane Pll would entail misalignment and / or torsional phenomena of the strip itself, thus complicating or compromising the effectiveness of the invention itself.

[0428] In step 3 and with reference to figure 16, following pure vertical translation, the first and second counter-rotating rollers 21 T, 212' have reached the close configuration CR, the deviation angle [3 is substantially equal to 90° and the stacking surface 10 is flanked on the right to the two rollers 21 T, 212'.

[0429] The separator strip NS is substantially abutted on the surface 10 and is further clamped by the first gripper 51 .

[0430] Still with reference to figure 16, at the end of step 3, the second release assembly of the electrode 300 has reached a position where it is above facing the stacking surface 10.

[0431] The first distance D1 is about equal to 3 mm while the second distance D2, measured as the shortest distance between any part of the first and second roller 21 T, 212' and any part of the stacking surface 10, is about equal to 7 mm.

[0432] In step 4, the "moving stop" begins. As argued above, we are in the following condition: the displacement vector of the first working path of the first and second rollers 21 T, 212’ coincides in direction and modulus with the displacement vector of the second working path of the stacking surface 10. This displacement vector is a pure downward oriented vertical translation (corresponding to a displacement having a negative value in the Z component only) by displacing the first and second rollers 21 T, 212' and the stacking surface in an integral manner from the close configuration CR to the extended configuration CE. Throughout the "moving stop" the deviation angle [3 is kept substantially equal to +90°.

[0433] At the end of step 4, a configuration equal to 6 / 7 of the extended CE configuration is reached and the "moving stop" ends, concluding the minimum close distance following step and the release of the second electrode 301 on the first folded layer of separator strip NS of the stacked structure S.

[0434] During step 4, the first and second rollers 21 T, 212', the stacking surface 10 and the second electrode release assembly 300 moved by the same displacement according to an identical displacement vector.

[0435] The first distance D1 and the second distance D2 have the same values as in step 3.

[0436] In step 5, the stacking surface 10 is displaced downwards and to the left similarly to step 2 but with the opposite direction of displacement. Consistently, the first and second rollers 21 T, 212' translate further downwards reaching the extended configuration CE.

[0437] In this step 5, the deviation angle [3 is reduced from +90° to 0°, returning to a situation equivalent to step 1 , with the differences being that now the separator strip NS is retained by the first gripper 51 and on the first folded layer of separator strip NS the electrode 301 has been placed.

[0438] Steps 6 to 10 represent the mirror image on the left of what occurred during steps 2 to 5 on the right, envisaging the intervention of the first electrode release assembly 200.

[0439] Consistently, therefore, at the end of step 10 (equivalent in spatial configuration of the apparatus 100 to that of step 1 ) two layers of separator strip NS will have been folded on the stacking surface 10 and two electrodes 301 , 201 (cathode and anode) will have been positioned.

[0440] As can be clearly seen, from step 10, the method 500 can continue with the new step 2 proceeding with the creation of the desired stacked structure S. More generally, all the elements described so far in relation to the embodiment illustrated in figure 1 may be combined with all the possible embodiments provided for by the present invention and described above.

[0441] Obviously, a person skilled in the art may, in order to meet specific and contingent application requirements, make further modifications and variants, all falling within the scope of protection as defined by the following claims.

Claims

CLAIMS1. Stacking apparatus (100) for stacking a separator strip (NS) and sheets of metal foil (201 , 301 ), comprising:- A dispensing unit (200) for dispensing said separator strip (NS) along a predefined feed path (PA),- A stacking unit (1 ) comprising a stacking surface (10) configured so as to receive said separator strip (NS) and said sheets of metal foil (201 , 301 ),- A first movement device (131 ) configured to reversibly displace an outgoing orientation control device (R2) acting on said separator strip (NS) and placed immediately upstream of said stacking unit (1 ), along a displacement direction (d) between a first configuration distal to said dispensing unit (200) and a second configuration proximal to said dispensing unit (200), wherein said first movement device (131 ) comprises an alignment device (205') configured to displace said outgoing orientation control device (R2) so as to align said separator strip (NS) to said predefined feed path (PA).

2. Apparatus (100) according to the preceding claim, wherein said alignment device (205') is configured to displace said outgoing orientation control device (R2), acting on said separator strip (NS), according to a translation direction (DT) transverse to said predefined feed path (PA).

3. Apparatus (100) according to the preceding claim, wherein:- said alignment device (205') comprises a first frame (215') including said outgoing orientation control device (R2) on which a first roller (21 T) and a second roller (212') are arranged, respectively rotating about a first and a second longitudinal axis (211 'X, 212'X), which are housed so as to be placed side by side to and spaced apart from each other so as to engage said separator strip (NS) between them along said predefined feed path (PA),- said first frame (215') may be translated according to said translation direction (DT) having a component parallel to said first and second longitudinal axis (211'X, 212'X).

4. Apparatus (100) according to the preceding claim, wherein said translation direction (DT) is substantially parallel to said first longitudinal axis (211X').

5. Apparatus (100) according to any one of claims 3 to 4, wherein:- said second roller (212') is constrained to a bracket (218'),- said bracket (218') is constrained to said first frame (215') with an allowed translation and is configured to reversibly displace between a close position, wherein said second roller (212') is at a minimum distance from said first roller (21 T), and a spaced-apart position, wherein said second roller (212') is at a maximum distance from said first roller (211 ').

6. Apparatus (100) according to one of the preceding claims, comprising a second movement device (132) of said stacking surface (10) configured to displace said stacking surface (10) along a second working path (P2), wherein said first and / or second movement device(s) (131 , 132) is / are configured to maintain a first distance (D1 ) between said outgoing orientation control device (R2) and said stacking surface (10), measured according to an outgoing reference direction (DRU), between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm.

7. Apparatus according to the preceding claim, wherein said first distance (D1 ) is substantially constant for at least 40%, more preferably for at least 50%, more preferably for at least 80%, even more preferably for at least 100% of the time of the second working path (P2).

8. Apparatus (100) according to claim 6 or 7, wherein said second movement device (132) is configured to move with a continuous movement said stacking surface (10) along said second path (P2) which defines a closed curve.

9. Apparatus (100) according to the preceding claim, wherein said first movement device (131 ) is configured as following, according to at least one component, said second movement device (132) when it displaces said stacking surface (10) with a continuous movement.

10. Method for creating a stacked structure (S) of a separator strip (NS), preferably for an electrochemical cell intended for producing batteries, comprising:- dispensing via a dispensing unit (200) said separator strip (NS) along a predefined feed path (PA),- stacking said separator strip (NS) on a movable stacking surface (10),- moving an outgoing orientation control device (R2), acting on said separator strip (NS) and placed upstream of said stacking unit (10), reversibly along a first working path (P1 ) between a first configuration distal to said dispensing unit (200) and a second configuration proximal to said dispensing unit (200) by means of a first movements 31 ),- arranging an alignment device (205'), included in said first movement device (131 ), configured to displace said outgoing orientation control device (R2),- Identifying a possible alignment difference (AAII) between said separator strip (NS) and said predefined feed path (PA),- In the event that said alignment difference (AAII) is other than zero, actuating said alignment device (205') and displacing said outgoing orientation control device (R2) so as to align said separator strip (NS) to said predefined feed path (PA) while said separator strip (NS) is being continuously dispensed.11 . Method according to the preceding claim, wherein- said alignment device (205') comprises a first frame (215') on which a first roller (21 T) and a second roller (212') are arranged, respectively rotating about a first and a second longitudinal axis (211 'X, 212'X), which are housed so as to be placed side by side to and spaced apart from each other so as to engage said separator strip (NS) between them along said predefined feed path (PA),- said first frame (215') is translatable according to a translation direction (DT) having a component parallel to said first and second longitudinal axis (211'X, 212'X).

12. Method according to claim 10 or 11 , comprising maintaining a first distance (D1 ) between said outgoing orientation control device (R2) and said stacking surface (10), measured according to said outgoing reference direction (DRU) of said separator strip (NS), between 0 and 30 mm, more preferably between 0 and 15 mm, even more preferably substantially equal to 0 mm.

13. Method according to any one of claims 10 to 12, comprisingArranging a first and / or a second release assembly (200, 300) of a sheet of metal foil configured to release a first or a second sheet ofmetal foil (201 , 301 ) on a portion of said separator strip (NS) at said stacking surface (10) upon an approaching movement (Mac) between said first or second release assembly (200, 300) of a sheet of metal foil and said stacking surface (10) to a minimum release distance (DmR) with said separator strip (NS),- Performing said approaching movement (Mac) so as to produce a condition of substantially zero relative speed between said first and / or second release assembly of a sheet of metal foil (200, 300) and said stacking surface (10) and having at least one displacement component parallel to said outgoing reference direction (DRU), preferably perpendicular to said stacking surface (10), even more preferably vertical,- Releasing on said portion of said separator strip (NS) at said stacking surface (10) said first or second sheet of metal foil (201 , 301 ).

14. Method according to the preceding claim, comprisingReleasing a first and second plurality of said first and second sheets of metal foils (201 , 301 ) respectively by interposing between each of them a folded tract of a separator strip (NS) of said stacked structure (S).

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