Apparatus and method for assembling a battery pack

Abstract

Described herein is an apparatus (1) for assembling together battery cells or battery modules having electrical terminals (T) that must undergo a welding operation. The apparatus (1) includes a tool (4) for engaging and holding the elements to be welded, which can be moved along at least two axes to transport and maintain one or more battery cells (C) or battery modules in a configuration and / or position suitable for welding the electrical terminals (T) to respective electrical connection elements (B) and / or welding the electrical terminals (T) to each other. The apparatus also includes a welding head (10) carried by the tool (4) and positioned to perform a welding operation on the elements to be welded. The tool (4) and the welding head (10) are controlled such that the tool transports the battery cell (C) or battery module (M) to the configuration and / or position suitable for performing the welding, and the tool (4) maintains the battery cell (C) or module (M) in the configuration and / or position by applying pressure, if necessary, against the elements to be welded while performing the welding. The tool (4) is configured such that the welding head (10) is operable to perform the welding while the tool maintains the battery cell (C) or battery module (M) in the configuration and / or position suitable for welding.

Description

[Technical field]

[0001] The present invention relates generally to an apparatus and method for assembling an electric battery.

[0002] The invention particularly relates to an apparatus for assembling together battery cells or battery modules, said battery cells or battery modules comprising electrical terminals which have to be subjected to a welding operation. [Background technology]

[0003] An apparatus of the above-mentioned type is known, for example from US Patent No. 8,460,817. However, the solution described in this document is not entirely satisfactory from various points of view, in particular in terms of simplicity of construction and in terms of speed and efficiency of assembly operations for assembling together battery cells or battery modules.

[0004] Further aspects to consider are the adaptability of the device to different types of battery cells and the simplicity of operations required for deployment at the manufacturing site and start-up of the device.

[0005] [Objective of the Invention] The object of the present invention is to produce a device of the type indicated above which is structurally simple, functional and highly versatile in use.

[0006] Another object of the present invention is to produce a device of the type presented above that can be easily and quickly adapted to different applications, in particular to different battery cell configurations.

[0007] Another object of the invention is to produce a welding device of the type presented above, which ensures excellent weld quality and simple and reliable control of the preliminary stage to welding, in which the elements to be welded are brought into a configuration suitable for welding.

[0008] Another object of the invention is to produce an apparatus of the type presented above which has compact dimensions and a simple and quick start-up / installation procedure so as to be particularly suitable for being transported and put into operation at different manufacturing sites.

[0009] Yet another object of the invention is to manufacture an apparatus of the type presented above, which makes it possible to monitor the quality of the weld beads produced with said apparatus. Summary of the Invention

[0010] According to one or more embodiments, one or more of the above objects are achieved through an apparatus having the particular characteristics specifically recited in the following claims.

[0011] In particular, the invention relates to an apparatus for assembling together battery cells or battery modules, said battery cells or battery modules comprising electrical terminals which have to be subjected to a welding operation, said apparatus comprising: a tool for engaging and holding the elements to be welded, which can be moved along at least two axes to transport and maintain one or more battery cells or battery modules in a configuration and / or position suitable for performing welding of the electrical terminals of the battery cells or modules to their respective electrical connection elements and / or welding of the electrical terminals together; a welding head carried on the tool and arranged to perform a welding operation on the element to be welded; Equipped with the tool and the welding head are controlled such that the tool transports the battery cell or battery module to the configuration and / or position suitable for performing the welding and maintains the battery cell or module in the configuration and / or position during the welding, if necessary by applying pressure against the elements to be welded; The tool is configured such that the welding head is operable to perform the weld while the tool maintains the battery cell or battery module in the configuration and / or position suitable for performing the weld.

[0012] According to a preferred feature of the invention, the welding head carried on the tool is configured to perform the welding whilst remaining in a remote position relative to the elements to be welded.

[0013] In one or more embodiments, the welding head is configured to move integrally with the tool along the at least two axes and is configured to move and / or oscillate along at least a third axis.

[0014] In one or more embodiments, the tool that engages and holds the elements to be welded is a bendable tool assembly configured to simultaneously bend one or more elements prior to welding.

[0015] In one or more embodiments, the apparatus includes a system for automatically controlling the quality of the weld performed via the welding head, implemented via at least one thermal camera configured to control the quality of the weld bead in the welding area.

[0016] In one or more embodiments, the system for automatically controlling the weld quality comprises a first thermal camera and a second thermal camera, the first thermal camera and the second thermal camera being controlled such that one of the first thermal camera and the second thermal camera is always aligned with a position where the head is located to perform the weld, and the other of the first thermal camera and the second thermal camera is positioned at a still further rearward position along a respective auxiliary guide bar, the further rearward position being aligned with a previous position of the weld head such that the thermal camera at the rearmost position controls the cooling phase of the weld bead after the weld has been performed.

[0017] In one or more embodiments, the equipment is transported as a whole on a single palletizable platform.

[0018] In one or more embodiments, the apparatus includes a service system for electrical and / or fluid supply to the apparatus and a "plug-in" type quick coupling device for coupling to an external system of power and / or fluid supply.

[0019] An embodiment also relates to a related method of assembling together battery cells or battery modules, said battery cells or battery modules comprising electrical terminals which have to be subjected to a welding operation, said method comprising the steps of: controlling the tool to engage and hold the elements to be welded along the at least two axes to transport and maintain one or more battery cells or battery modules in a configuration and / or position suitable for performing welding of the electrical terminals of the battery cells or modules to respective electrical connection elements and / or welding the electrical terminals together; welding the component via the welding head carried by the tool; Equipped with.

[0020] Embodiments also relate to associated methods of controlling the quality of the weld performed via the above-described device, as set forth in the appended claims.

[0021] Thanks to the above mentioned characteristics, the device according to the invention offers a series of advantages, in particular: The device according to the invention ensures high weld quality and simple and reliable control of the preliminary stages to welding, in which the elements to be welded are brought into a configuration and / or position suitable for carrying out the weld; The apparatus of the present invention allows for simultaneous bending of rows of terminals of multiple side-by-side cells prior to welding of the terminals; The device according to the invention is compact in size, has a simple and quick start-up / installation phase and is easily transportable to different manufacturing sites; The device according to the invention can be easily and quickly adapted to different applications and therefore offers high versatility of use; The device according to the invention makes it possible to monitor the quality of the weld beads produced with the welding head which is part of the device, and also to control the cooling phase of each weld bead, so that no delays are induced in the cycle time of the device. [Brief description of the drawings]

[0022] Further characteristics and advantages of the present invention will become apparent from the following description, given purely by way of non-limiting example, with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 is a perspective view of an apparatus for assembling battery cells or battery modules together according to a preferred embodiment of the present invention. [Diagram 2] FIG. 1 is a perspective view of an apparatus for assembling battery cells or battery modules together according to a preferred embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic cross-sectional view of the device shown in the previous figure. [Figure 4] FIG. 2 is a schematic perspective view of an enlarged scale of a battery pack to be assembled via the device according to the present invention; [Figure 5A] 1A-1D are schematic cross-sectional views illustrating several steps of a method that can be carried out using the device according to the invention; [Figure 5B] 1A-1D are schematic cross-sectional views illustrating several steps of a method that can be carried out using the device according to the invention; [Figure 5C] 1A-1D are schematic cross-sectional views illustrating several steps of a method that can be carried out using the device according to the invention; [Figure 6] 5A-5C are schematic plan views illustrating further steps of a method that can be carried out using the device according to the invention; [Figure 7] 5A-5C are schematic plan views illustrating further steps of a method that can be carried out using the device according to the invention; [Figure 8] 5A-5C are schematic plan views illustrating further steps of a method that can be carried out using the device according to the invention; [Figure 9] 5A-5C are schematic plan views illustrating further steps of a method that can be carried out using the device according to the invention; [Figure 10] FIG. 13 is a perspective view of an apparatus according to an additional embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] In the following description, various specific details are set forth for a thorough understanding of one or more example embodiments. An embodiment may be practiced without one or more of the specific details or with other methods, components, materials, etc. In other cases, known structures, materials, or operations are not shown or described in detail to avoid obscuring various aspects of the embodiments. Reference to "one embodiment" in the context of this specification indicates that a particular configuration, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, phrases such as "in one embodiment" that may appear in various places in this specification do not necessarily refer to the same embodiment. Moreover, particular features, structures, or characteristics may be combined in a suitable manner in one or more embodiments and / or may be associated with an embodiment in a different manner than as shown herein, for example, characteristics illustrated herein in connection with one drawing may be applied to one or more embodiments illustrated in a different figure.

[0024] References provided herein are merely for convenience and therefore do not define the field of protection or the scope of the embodiments.

[0025] 1 to 3 are schematic diagrams showing an apparatus 1 for assembling a battery cell C or a battery module M according to an embodiment of the present invention.

[0026] Some structural details of the device are not shown in the accompanying drawings since they can be made according to techniques well known in the referenced technical field.

[0027] It should be noted that the apparatus shown in the drawings are only example embodiments that may be made in accordance with the present invention, as the present invention is generally applicable to any apparatus for assembling together battery cells or battery modules incorporating the unique characteristics recited in the appended claims.

[0028] The device 1 according to the invention is designed to assemble together battery cells C or battery modules M, which are provided with electrical terminals T that have to be subjected to a welding operation, which can be welded together and / or to respective electrical connection elements.

[0029] The apparatus 1 can be used to assemble various types of battery cells and / or modules, for example cells that make up a battery pack for a vehicle having a pure electric or hybrid propulsion system.

[0030] Fig. 4 is an enlarged scale view of an example of a battery pack P on which the device 1 can operate. According to a technique known per se, the battery pack P is defined by a number of modules M, each of which comprises a number of battery cells C (in the example shown, of the "pouch" type, having a flat and elongated body) arranged side by side in several rows and having respective electrical terminals T. In order to make the battery pack P function, the terminals T of the cells C of each row of side by side cells must be welded to a respective conductive bar B (busbar) associated with the cell C. As can be seen in Fig. 4, each conductor bar B that will be electrically connected to the terminals T of the respective row of cells C is constructed in the form of an elongated plate with parallel slots, from which the terminals T project. According to the embodiment shown in the drawing, the electrical terminals T have a laminar shape that projects vertically from the respective slots of the respective bar B. Before proceeding with the welding of the terminals T to the conductive bar B, the electrical terminals T must be bent in order to achieve a bent configuration of the terminals T suitable for proceeding with the welding. Referring again to the specific example of FIG. 4 , a row of terminals T (the leftmost row in the drawing) is shown in a pre-bent configuration, where the terminals T are vertically spaced and protrude through a series of slits obtained on the cells C, while a row of terminals T (the rightmost row in the drawing) is shown in a bent configuration, where the terminals T are bent horizontally relative to the conductive bar B to which the terminals T must be welded.

[0031] In the accompanying drawings, the device 1 is associated with a battery pack P having the characteristics indicated above. However, as already indicated above, the device 1 can also be used to assemble other types of battery cells and modules not shown in the drawings.

[0032] In one or more embodiments of the invention, as will be explained in more detail below, the moving parts of the device 1 for carrying out the assembly of the cell C are: an engagement and holding tool 4 designed to transport and maintain one or more battery cells C in a configuration and / or position suitable for undergoing a welding operation; a welding head 10 arranged to weld a terminal T; Includes.

[0033] According to a first related characteristic of the invention, the engagement and holding tool 4 can be moved along at least two axes and the welding head 10 is carried on the tool 4 so as to provide a single movement system designed to perform both the preparatory steps for welding, and the welding step of the elements to be welded, while keeping the cell C in a configuration suitable for undergoing a welding operation.

[0034] As will be further shown in the following description, the engagement and holding tool 4 is controlled to keep the cell C in the above-mentioned configuration during the performance of the welding of the elements to be welded.

[0035] Now, in the following description, the embodiment shown in Figs. 1 to 3 will be described in detail.

[0036] With reference to the perspective views of Figures 1 and 2, the welding device 1 comprises a support structure 2 defining at least one seat 3 on which a battery pack P to be assembled is placed. Details concerning the seat 3 are not shown in the accompanying drawings since, as indicated above, these details can be made according to any prior art.

[0037] According to this example embodiment, the tool 4 carrying the head 10 is movably mounted on the support structure 2 along two mutually orthogonal axes according to an overall configuration substantially similar to that of a Cartesian robot, thus ensuring high accuracy and repeatability properties.

[0038] The support structure 2 is shown in the attached drawings very diagrammatically, as it can be made according to any configuration known in the art of reference. Actuators that can be used to control the movement of the moveable parts relative to the support structure 2 are also shown in the attached drawings, these are very diagrammatically and can be made in any known manner.

[0039] According to the embodiment shown in Figures 1-3, the assembly supported by the support structure 2 includes a bending tool assembly 4 configured to simultaneously bend one or more elements prior to welding. As will be shown in more detail in the following description, the bending tool assembly 4 includes a terminal press bar 5 configured to simultaneously bend the electrical terminals T of multiple side-by-side cells C.

[0040] The terminal pressing bar 5 is supported above the battery pack P against which the device 1 has to operate and is movable together with the whole assembly both in a first horizontal direction X and in a vertical direction Z. According to the example shown in Figures 1 to 3, the above-mentioned first horizontal direction X is perpendicular to the longitudinal direction of the terminal pressing bar 5.

[0041] The position of the assembly 4 is controlled along the above-mentioned first horizontal direction X by respective actuators A1, A2, shown purely diagrammatically in the drawings. The actuators A1, A2 can be electric or fluid actuators, made in any known manner. According to the illustrated example, the bending tool assembly 4 can move according to the first horizontal direction X through the sliding of a pair of carriages 23, 24 slidably mounted on respective end guides 19, 20. Opposite ends of the bending tool assembly 4 are connected to and supported by the carriages 23, 24. The components of these actuators are not shown in the attached drawings, since the actuators A1, A2, as mentioned above, can be made according to any known configuration, and because the removal of these details from the drawings makes the drawings simpler and easier to understand.

[0042] The reference A3 denotes an additional actuator configured to effect a movement of the bending tool assembly 4 along the vertical direction Z. The actuator A3 can be made according to any technique known per se to convert a rotational movement into a linear movement along the vertical direction Z.

[0043] According to the example shown in the drawings, two actuators A3 are arranged proximate to each carriage 23, 24, respectively, and are designed to operate simultaneously to achieve a vertical movement of the assembly 4. As will be shown in more detail later in the description, the actuators A1, A2, A3 control the movement of the bending tool assembly 4 to achieve the horizontal movement along the first direction X and the vertical movement along the direction Z to complete the stage of bending the terminal T, preliminary to the welding stage.

[0044] As shown in particular in the perspective views of Figures 1 and 2, the bending tool assembly 4 supports a frame 6 configured to move together with the bending tool assembly 4 along a first horizontal direction X and a vertical direction Z. The frame 6 is spaced at an elevated and remote position relative to the terminal pressing bar 5 and carries a welding head 10 configured to perform the welding of the electrical terminals T. According to this embodiment, the welding head 10 is configured to perform the welding while remaining in a remote position relative to the elements to be welded. Still according to the embodiment shown in Figures 1 to 3, the welding of the terminals T is performed following the stage of bending of the electrical terminals T achieved via the bending tool assembly 4, creating a weld bead connecting each terminal T to a respective conductive bar B.

[0045] According to a feature of the present invention, the welding head 10 is adapted to move integrally with the tool 4 .

[0046] With reference to the illustrated example, the welding head 10 is movably mounted on a frame 6 along a second horizontal direction Y perpendicular to the first direction X. More specifically, the frame 6 includes a guide bar 7 perpendicular to the first horizontal direction X and spaced apart at an elevated position from a terminal push bar 5 of the tool assembly 4.

[0047] The welding head 10 is movably mounted (along direction Y) on the guide bar 7 and is positioned to emit a welding beam that passes through at least one opening 11 provided on the terminal press bar 5. It will thus be appreciated that the welding head 10 is mounted on a frame 6 configured for movement integrally with the bending tool assembly 4 along a first horizontal direction X and a vertical direction Z, resulting in the head 10 being movable along three mutually orthogonal axes (X, Y, Z) according to an arrangement substantially similar to that of a Cartesian coordinate robot.

[0048] A frame 6, which is configured to move while carrying a welding head 10 integrally with the terminal pressing bar 5, is shown diagrammatically in the attached drawings. According to the diagrammatic example shown, the frame 6 may comprise vertical parts 13, 14, 15, which are configured to support the respective ends of the above-mentioned horizontal guide bar 7. The vertical parts 13, 14, 15, which are arranged on either side of the terminal pressing bar 5, are carried by respective end parts 12 of the bending tool assembly 4. In the embodiment shown in the drawings, the above-mentioned end parts 12 are bar-like end parts perpendicular to the terminal pressing bar 5, where the extension of the bar-like end parts 12 is significantly shorter than the longitudinal extension of the terminal pressing bar 5. Referring again to the particular example shown in the drawings, the vertical parts of the frame 6 comprise a pair of vertical rods 13, each connected at one of its upper ends to a respective end of the horizontal guide bar 7 carrying the head 10. The vertical rods 13 are each supported by the bar-like end portion 12 of the assembly 4 and comprise a lower portion connected to one of the carriages 23, 24 for achieving movement along the horizontal direction X.

[0049] As indicated above, the actuator A3 controlling the movement of the assembly 4 and of the frame 6 carrying the head 10 along the vertical direction Z can be made according to a screw / nut mechanism operated by an electric motor or in any other known manner. According to a particular embodiment, this mechanism can also be implemented via a recirculating ball screw mechanism.

[0050] The actuators A1, A2, A3 operate the bending tool assembly 4 and the frame 6 carrying the head 10 to perform a horizontal movement along a first direction X and a vertical movement along a direction Z to complete the bending stage of the terminal T prior to welding. Furthermore, as also shown below, the bending tool assembly 4, and in particular the terminal pressing bar 5, is controlled to hold the terminal T in a bending position during the welding stage performed by the head 10. The actuators A1, A2, A3 can be controlled via a control circuit to move the bending tool assembly 4 (and the head 10) along a predefined bending path to bend the metal terminal T prior to welding.

[0051] As indicated above, the welding head 10 is movably mounted on the above-mentioned guide bar 7 along direction Y and is positioned to emit a welding beam which passes through at least one opening 11 provided on the terminal pressure bar 5.

[0052] As shown in particular in the schematic cross-sectional view of Figure 3, the welding head 10 is mounted on the guide bar 7 via a support element 16 slidably mounted on the bar 7. Reference A4 designates another actuator designed to move the welding head 10 along the horizontal bar 7 and thus along the horizontal direction Y. With reference to the particular embodiment shown in the drawings, the support element 16 has an L-shaped configuration defining a horizontal plane 21 on which the head 10 is supported.

[0053] In one or more embodiments, and in the embodiment shown in the drawings, the welding head 10 is a laser focusing head of any known type having a vertical axis Z1 and includes a support structure 22 with a flange connecting the support element 16 to a horizontal surface 21.

[0054] According to techniques known per se, the head 10 may receive a laser beam from a laser generator via an optical fiber. The device 1 may therefore comprise a laser source (not shown in the drawings) associated with the welding head 10. The laser source and the welding head 10 may be controlled via respective control circuits, which are also not shown in the accompanying drawings. The construction details of the welding head 10 and the laser source, as already indicated, can be made in any known manner and these details do not fall, on their own, within the scope of the present invention, so they are not shown here.

[0055] The welding head 10 is supported vertically by a support element 16 and is arranged away from the terminal pressure bar 5 and from the terminals T to be welded, so that the welding beam (schematically indicated by the dotted line L in FIG. 3) is at the correct focusing distance for the components to be welded, so that it effectively achieves the welding of the terminals T. To perform the welding of the terminals T, the head T is arranged so as to be vertically aligned with the openings 11 of the terminal pressure bar 5. According to the embodiment shown in FIGS. 1 to 9, the openings 11 are arranged side-by-side along the longitudinal extension of the terminal pressure bar 5. The openings 11 have a rectangular shape and have a tapered shape along the vertical direction Z in the direction of the terminals T of the cells C (FIG. 3).

[0056] As indicated above, the head 10 and the assembly 4 form a single movement system configured to perform the assembly of the cell C. One or more electronic units (not shown in the drawings) may be provided for controlling the assembly 4 and the head 10. The actuators A1, A2, A3, A4 may be controlled via a control circuit to move the bending tool assembly 4 (and the head 10) along a predefined bending path to bend the terminal T before welding, and to move the head 10 along a predefined welding path to weld the terminal T to the conductive bar B associated with the cell C.

[0057] Optionally, one or more embodiments of device 1 may include an auxiliary control feature that controls the vertical movement and / or vibration of head 10 in addition to the movement of head 10 that is integral with assembly 4. Thanks to this feature, it is possible to vary the distance of head 10 from terminal T, thereby making the device even more versatile for different applications.

[0058] The welding head 10 can be made according to any known welding device, with or without contact with the elements to be welded, such as, for example, a laser welding head, etc. In one or more embodiments, the welding head 10 can be an electric spot welding device having an electrode that is movable along a vertical direction.

[0059] As indicated above, the welding apparatus 1 shown in Figures 1 to 3 is configured to perform a bending step of the terminal T to be welded via the bending tool assembly 4 prior to welding of the terminal T.

[0060] 5A-5C are schematic cross-sectional views showing several stages of a method of assembling a battery pack P that can be carried out via the device 1 shown in FIGS. 1-3. The cross sections in FIGS. 5A-5C are made according to a vertical plane perpendicular to a horizontal direction Y. In FIG. 5A, a part of the terminal pressing bar 5 is placed alongside a row of terminals T of a module M including a row of cells C. In FIG. 5B, the bending tool assembly 4 is controlled to perform a horizontal movement along a first direction X such that the terminal pressing bar 5 bends the terminals T. According to the example of the drawings, the terminals T having a laminar shape protruding vertically from the upper wall of the battery pack P are placed in a bent configuration in the direction of the cells C and the conductive bars B. Then, as shown in FIG. 5C, the terminal pressing bar 5 is controlled to perform a vertical movement along a direction Z such that the terminals T are placed in a bent configuration in contact with the conductive bars B associated with the cells C. At this point, once the bending stage is completed, the terminal pressure bar 5 remains in a lowered position relative to the cell C and the bar B, and the welding head 10 is controlled to emit the welding beam through the opening 11 and weld the bent terminal T on the respective conductive bar B. Thanks to these properties, the device according to the invention ensures a simple and reliable control of the bending stage of the terminals to be welded, before the welding of the terminals. Moreover, in order to complete the welding of the terminals T, no further components need to be prepared to hold the elements to be welded in place, before creating the weld bead.

[0061] According to a preferred characteristic of the invention, the device 1 comprises a system for automatically controlling the quality of the weld performed by the welding head 10. Naturally, this system can be associated with any type of device 1 according to the invention, without any limitation to the embodiment shown in the drawings.

[0062] In one or more embodiments, this system for automatic quality control is implemented via at least one thermal camera arranged to control the quality of the weld bead in the welding area. Said thermal camera can be made according to the techniques described in the Italian patent application No. 102018000021022 by the same applicant, said Italian patent application forming part of the state of the art according to IPC article 46(3). Naturally, the quality control system may comprise one or more devices different from said thermal camera, such as for example ultrasound, tomography, X-ray machines, etc.

[0063] In the embodiment shown in the drawings, the frame 6 comprises a first auxiliary horizontal guide bar 8 and a second auxiliary horizontal guide bar 9 on which a first thermal camera 17 and a second thermal camera 18, respectively, are slidably mounted. Each auxiliary horizontal guide bar 8, 9 is spaced apart from and parallel to the guide bar 7 carrying the head 10, along a respective side of the bar 7. The thermal cameras 17, 18 are therefore able to move along the above-mentioned second horizontal direction Y, just like the head 10. Each auxiliary guide bar 8, 9 is supported at its ends by a respective pair of vertical rods 14, 15. In a manner entirely similar to that described above for the rod 13 of the horizontal bar 7 carrying the head 10, the rods 14, 15 each comprise a lower portion supported by a bar-like end portion 12 of the bending tool assembly 4.

[0064] According to what is described in Italian patent application no. 102018000021022, each thermal camera 17, 18 is configured to provide a thermal image showing the welding area. During the operating state of the head 10, the beam delivered by the welding head 10 moves along a welding path, heating the material of the components to be welded in the welding area, thus creating a weld bead by melting the material of these components. The thermal cameras 17, 18 are configured to provide a two-dimensional image in which the value of each pixel identifies the temperature of the respective spot of the welding area. The thermal image is then processed by a processing circuit, for example a microprocessor programmed with a software code. In particular, by performing a weld, the pixels in the welding area will have a higher value (i.e. a higher temperature) and therefore the processing circuit is able to detect an area in the thermal image corresponding to the welding area. The processing circuit is configured to compare the value of each pixel of the thermal image with a reference threshold, to select pixels having a value greater than a predefined threshold, and to approximate the area in which the selected pixels are identified with a rectangular or trapezoidal area. In various embodiments, this region is divided into a number of sub-regions, and for each sub-region the respective temperature is determined as a function of the values ​​of the pixels contained in the respective sub-region. Thanks to these properties, it is possible to monitor temperature trends and to estimate the quality of the welds performed.

[0065] As indicated above, the thermal cameras 17, 18 are slidably mounted on respective auxiliary horizontal guide bars 8, 9. The positions of the thermal cameras 17, 18 are controlled along a second horizontal direction Y by respective actuators A5, A6. The actuators A5, A6 may be electric or fluid actuators made in any known manner similar to the actuator A4 that controls the head 10. Preferably, the cameras 17, 18 are also configured to be capable of rotating 360 degrees for monitoring large welding areas.

[0066] In accordance with a feature of the present invention, the cameras 17, 18 are controlled to slide along their respective horizontal auxiliary guide bars 8, 9 to follow the movement of the welding head 10 over the bar 7 so as to analyze the quality of the weld performed by the head 10 in real time as the head 10 proceeds to weld the terminal T. As will become apparent from the detailed description below, the thermal cameras 17, 18 are controlled to monitor the quality of the weld without including periods of inactivity in the quality control operating cycle due to the movement of the thermal cameras to follow the movement of the head 10.

[0067] 6 to 9 are schematic plan views showing the device 1 and in particular the movement of the welding head 10 and the cameras 17, 18 along the respective guide bars 7, 8, 9 during a work cycle.

[0068] As shown in these figures, the thermal cameras 17, 18 are controlled such that one of the first and second cameras 17, 18 is always aligned with the position where the head 10 is located to perform the weld, and the other of the first and second cameras 17, 18 is located at a position still further rearward along the respective guide bars 8, 9. This rearmost position is aligned with the previous position of the welding head 10 such that the rearmost thermal camera 17, 18 controls the cooling phase of the weld bead after performing the weld.

[0069] In Fig. 6, head 10 is in a first position along horizontal guide bar 7 to perform a first welding step through first opening 11 obtained on terminal push bar 5. One of first camera 17 and second camera 18 is positioned in alignment (with respect to horizontal direction Y) with respect to the position of head 10 to monitor the quality of the weld performed by head 10. The other of said first camera 17 and second camera 18 is positioned in a more advanced position along horizontal direction Y to "wait" for welding head 10 when, upon completion of the first welding step, welding head 10 will position itself in a more advanced position to perform a second welding step through second opening 11.

[0070] In FIG. 7 the welding head 10 has been moved along the bar 7 in order to place itself in a second position suitable for carrying out a second welding step through the second opening 11 .

[0071] In Fig. 8 the second camera 18 has been moved to a third position aligned along the horizontal direction Y with respect to a third position where the welding head 10 is positioned to perform a further welding step. In this figure the first camera 17 monitors the welding step that the head 10 performs through the second opening 11. In Fig. 9 the head 10 has been moved from the second position to the third position with the second camera 17 in place and ready to monitor the welding to be performed in this third position.

[0072] In summary, according to the method described above, the cameras 17, 18 are controlled via respective actuators A5, A6 such that one of them is always ready to monitor the welding performed by the head 10 following its movement along the bar 7.

[0073] Thanks to these properties, the device 1 is designed to monitor the quality of the weld bead produced with the welding head 10. Furthermore, since periods of inactivity in the operating cycle are eliminated due to the movement of the cameras 17, 18 as a result of the movement of the head 10 to weld the rows of terminals T, the time required to perform the completion of a welding cycle and to monitor its quality is significantly reduced.

[0074] In one or more embodiments, the device is equipped with a service system for the electrical and / or fluid supply to the device and is equipped with a "plug-in" type quick coupling device for coupling to an external power and / or fluid supply system, and thanks to these characteristics, the start-up / installation phase of the device 1 is extremely simple and fast.

[0075] Moreover, in accordance with a preferred feature of the present invention, the apparatus 1 as a whole is transported on a single palletizable platform.

[0076] Thanks to all the above indicated characteristics, the welding device 1 according to the invention is compact in size, has a simple and fast start-up phase and is particularly suitable for transporting to different production sites without having to resort to complex transport and / or installation operations.

[0077] The apparatus 1 may also include a light-tight booth (not shown in the drawings) that encloses the frame 6 carrying the head 10 such that the apparatus 1 has all the components required for its operation "on-board" without having to rely on the assembly of additional components prior to operation.

[0078] Naturally, the details of the construction of the above described embodiment may vary widely. This applies as much to the actuators A1, A2, A3, A4, A5, A6 as it does to the configuration of the terminal pressure bar 5, the support frame 6, the welding head 10 and the thermal cameras 17, 18.

[0079] Fig. 10 shows another embodiment of the device 1 according to the invention, where the engagement and holding tool 4 is a roller tool configured to carry and maintain the elements to be welded in a configuration suitable for performing the weld. The tool thus comprises a roller body 25 carried by an operating arm configured to apply pressure against the elements to be welded. In the example shown, the operating arm extends along a vertical direction and is supported by a support element 16 carrying the head 10. The roller tool is configured so that the head 10 may be operated to weld the elements to be welded, while the tool maintains the terminal T in the above-mentioned configuration suitable for performing the weld. Naturally, the device 1 shown in Fig. 10 is only another example embodiment of a device made according to the invention, as specified in the appended claims.

[0080] According to another preferred characteristic of the invention, the device 1 can be automatically reconfigured according to the requirements, without the assistance of an operator, for example following the reading of a QR code arranged on the battery pack or on the bending tool assembly, to accommodate different types of batteries. For example, a reconfiguration of the programs controlling the tool assembly and the movement of the welding head can be envisaged. Furthermore, it is possible to provide a tool store with different terminal pressing bars configured and arranged to work for battery packs having different configurations and / or dimensions. In this case, the tool assembly is connected to its support structure via a quick coupling device that allows an automatic tool change.

[0081] Thus, as is evident from the above description, the welding device according to the invention has a number of distinct advantages, in particular: The device according to the invention ensures high weld quality and simple and reliable control of the preliminary stages to welding, in which the elements to be welded are brought into a configuration and / or position suitable for carrying out the weld; The apparatus of the present invention allows for simultaneous bending of rows of terminals of multiple side-by-side cells prior to welding of the terminals; The device according to the invention is compact in size, has a simple and quick start-up / installation phase and is easily transportable to different manufacturing sites; The device according to the invention can be easily and quickly adapted to different applications and therefore offers high versatility of use; The device according to the invention makes it possible to monitor the quality of the weld beads produced with the welding head which is part of the device and also to control the cooling phase of each weld bead, so that no delays are induced in the cycle time of the device.

[0082] Naturally, the details of construction and the embodiments may vary widely from those described and illustrated solely by way of example, without prejudice to the principles of the invention and without departing from the scope of the invention as defined by the appended claims. (Other possible items) [Item 1] 1. An apparatus for assembling a battery cell or a battery module, the battery cell or the battery module comprising electrical terminals which must be subjected to a welding operation, the apparatus comprising: a tool for engaging and holding the elements to be welded, which can be moved along at least two axes to transport and maintain one or more battery cells or battery modules in a configuration and / or position suitable for welding the electrical terminals of the battery cells or modules to their respective electrical connection elements and / or for welding the electrical terminals to each other; a welding head carried by the tool and arranged to perform a welding operation on the element to be welded; Equipped with the tool and the welding head are controlled such that the tool transports the battery cell or battery module to the configuration and / or position suitable for performing the welding, and the tool maintains the battery cell or module in the configuration and / or position while performing the welding, by applying pressure, if necessary, against the elements to be welded; The apparatus, wherein the tool is configured such that the welding head is operable to perform the welding while the tool maintains the battery cell or battery module in the configuration and / or position suitable for welding. [Item 2] 2. The apparatus of claim 1, wherein the welding head carried by the tool is configured to perform the welding while remaining in a remote position relative to the elements to be welded. [Item 3] Item 1, wherein the welding head is configured to be movable integrally with the tool along the at least two axes, and the welding head is configured to move and / or oscillate along at least a third axis. [Item 4] Item 1, the apparatus of item 1, wherein the tool that engages and holds the elements to be welded is a bending tool assembly configured to simultaneously bend one or more elements as a prelude to the weld. [Item 5] Item 5. The apparatus of item 4, wherein the bending tool assembly comprises a terminal press bar configured to simultaneously bend the electrical terminals of multiple side-by-side cells prior to welding the electrical terminals. [Item 6] 6. The apparatus of claim 5, wherein the welding head is positioned to emit a welding beam that passes through at least one opening provided on the terminal press bar such that the welding head is configured to weld the element after bending the electrical terminal through the terminal press bar while the terminal press bar holds the electrical terminal in a welding position. [Item 7] 7. The apparatus of claim 6, wherein the terminal pressure bar carries a guide bar perpendicular to a first horizontal direction, positioned at a position higher than the terminal pressure bar and spaced apart from the terminal pressure bar, and the welding head is movably mounted on the guide bar along a second horizontal direction. [Item 8] Item 8. The apparatus of item 7, wherein the guide bar is part of a frame supported via the bending tool assembly, the frame connected to the bending tool assembly such that the frame is movable integrally with the bending tool assembly along the first horizontal direction and along a vertical direction. [Item 9] 2. The apparatus of claim 1, further comprising a system for automatically controlling the quality of the weld performed via the welding head. [Item 10] 10. The apparatus of claim 9, wherein the automatically controlling system comprises at least one thermal camera configured to check the quality of a weld bead in a welding area. [Item 11] Item 11. The apparatus of item 10, wherein the at least one thermal camera is configured to provide an image in which a value of each pixel identifies a temperature of a respective spot of the welding area so as to estimate the quality of the welding being performed. [Item 12] 12. The apparatus according to item 10 or 11, wherein the frame comprises two auxiliary guide bars parallel to and spaced apart from each other, on which the first thermal camera and the second thermal camera are slidably mounted, respectively. [Item 13] the thermal camera is controllable to slide along the respective auxiliary guide bar, following the movement of the welding head on the guide bar, to analyze the quality of the weld performed by the welding head in real time while the welding head performs the welding of the electrical terminal; and the thermal cameras are controllable such that one of the first and second thermal cameras is always aligned with a position where the welding head is located to perform the welding, and the other of the first and second thermal cameras is still located at a further rearward position along the respective auxiliary guide bar, the further rearward position being aligned with a previous position of the welding head such that the thermal camera in the rearmost position controls a cooling phase of the weld bead after the welding has been performed. Item 13. The device according to item 12, [Item 14] The apparatus described in item 1, wherein the apparatus is equipped with a service system for electrical and / or fluid supply to the apparatus, the apparatus is transported on a single palletizing platform, and the apparatus is equipped with a "plug-in" type quick coupling device for coupling to an external power and / or fluid supply system. [Item 15] A method of assembling together battery cells or battery modules, said battery cells or battery modules comprising electrical terminals which must be subjected to a welding operation, said method comprising the steps of: Providing a device according to any one of items 1 to 14; controlling the tool to engage and hold the elements to be welded along the at least two axes to transport and maintain one or more battery cells or battery modules in a configuration and / or position suitable for welding the electrical terminals of the battery cells or modules to respective electrical connection elements and / or welding the electrical terminals to each other; welding the component via the welding head carried by the tool; A method comprising: [Item 16] A method for checking the quality of the welding carried out via an apparatus for assembling battery cells or battery modules, the battery cells or battery modules comprising electrical terminals which must be subjected to a welding operation, the method comprising the steps of: Providing an apparatus according to claim 1, comprising an automatic control system for checking the quality of the weld performed via the welding head; controlling the automatic control system to automatically check the quality of the weld to analyze the quality of the weld performed by the weld head in real time while the weld head proceeds to weld the electrical terminal; A method comprising: [Item 17] The automatic control system for checking the quality of the weld comprises a first thermal camera and a second thermal camera configured to provide an image in which a value of each pixel identifies a temperature of a respective spot of a welded area so as to estimate the quality of the weld performed, the method comprising: controlling one of the first thermal camera and the second thermal camera such that the one is always aligned with a position where the welding head is located to perform the welding; controlling the other of the first and second thermal cameras to a further rearward position, the further rearward position being aligned with a previous position of the welding head such that the first and second thermal cameras at the rearmost positions control a cooling phase of the weld bead after performing the welding; 17. The method of claim 16, further comprising:

Claims

1. An apparatus for assembling a battery pack comprising a plurality of battery modules, each of which includes a plurality of battery cells arranged along a first direction, arranged along a second direction intersecting the first direction, each of the plurality of battery cells having an electrical terminal that must be subjected to a welding operation, the apparatus comprising: a tool including a bending tool assembly configured to move along the first direction to simultaneously bend a plurality of electrical terminals of a plurality of battery cells arranged along the second direction across the plurality of battery modules among the plurality of battery cells as a preparation for welding the plurality of electrical terminals of the plurality of battery cells to respective electrical connection elements and / or welding the plurality of electrical terminals to each other, and then maintain the plurality of electrical terminals in a bent state; a welding head carried by the tool so as to be transportable along the first direction and the second direction and arranged to perform a welding operation on the element to be welded; Equipped with the tool controls the bending tool assembly to transport the bending tool assembly and the welding head along the first direction to a position suitable for performing the welding operation, and to maintain the electrical terminals of the battery cells arranged along the second direction across the battery modules in the bent state by applying pressure, if necessary, against the elements to be welded during the welding operation; The tool is configured such that the welding head is operable to convey the welding head along the second direction to perform the welds while the bending tool assembly maintains the plurality of electrical terminals in the bent state.

2. The apparatus of claim 1 , wherein the welding head carried by the tool is configured to perform the welding while remaining in a remote location relative to the elements to be welded.

3. 2. The apparatus of claim 1, wherein the welding head is configured to be movable together with the tool along the first direction and along the tool along the second direction, and the welding head is configured to move and / or oscillate along a third direction that intersects at least the first and second directions.

4. the bending tool assembly includes a terminal pressing bar configured to simultaneously bend the electrical terminals of the plurality of battery cells arranged along the second direction before welding the electrical terminals.

2. The apparatus of claim 1.

5. The device described in claim 4, wherein the terminal pressing bar is provided corresponding to the plurality of battery cells arranged along the second direction and includes a plurality of openings extending along the second direction.

6. 6. The apparatus of claim 5, wherein the welding head is positioned to emit a welding beam that passes through the plurality of openings in the terminal press bar such that the welding head is configured to weld the element after bending the electrical terminal through the terminal press bar while the terminal press bar holds the electrical terminal in a welding position.

7. 7. The apparatus of claim 6, wherein the terminal pressure bar carries a guide bar along the first direction, the guide bar extending along the second direction, positioned at a position higher than the terminal pressure bar and spaced apart from the terminal pressure bar, and the welding head is movably mounted on the guide bar along the second direction.

8. 8. The apparatus of claim 7, wherein the guide bar is part of a frame supported via the bending tool assembly, the frame being connected to the bending tool assembly so as to be movable integrally therewith along the first direction and along a third direction intersecting the first direction and the second direction.

9. the apparatus includes a system for automatically controlling the quality of the weld performed via the welding head; The apparatus of claim 1 , wherein the automatically controlling system comprises at least one thermal camera configured to check the quality of a weld bead in a welding area.

10. 10. The apparatus of claim 9, wherein the at least one thermal camera is configured to provide an image in which a value of each pixel identifies a temperature of a respective spot of the weld area so as to estimate the quality of the weld performed.

11. the frame includes two auxiliary guide bars parallel to each other and spaced apart from each other in the first direction, on which the first thermal camera and the second thermal camera are respectively slidably mounted along the second direction; 11. Apparatus according to claim 9 or 10.

12. the thermal camera is controllable to slide along the second direction along each of the auxiliary guide bars to follow the movement of the welding head on a guide bar to analyze the quality of the weld performed by the welding head in real time while the welding head performs the welding of the electrical terminal; and the thermal cameras are controllable such that one of the first and second thermal cameras is always aligned with a position where the welding head is located to perform the welding, and the other of the first and second thermal cameras is still located at a further rearward position along the respective auxiliary guide bar, the further rearward position being aligned with a previous position of the welding head such that the thermal camera in the rearmost position controls a cooling phase of the weld bead after the welding has been performed. The device according to claim 11 , characterized in that

13. 2. The apparatus of claim 1, wherein the apparatus is equipped with a service system for electrical and / or fluid supply to the apparatus, the apparatus is transported on a single palletizing platform, and the apparatus is equipped with a "plug-in" type quick coupling device for connecting to an external power and / or fluid supply system.

14. A method for assembling the battery pack, in which the battery modules, each including the battery cells arranged along the first direction, are arranged along the second direction, each of the battery cells having an electrical terminal that must be subjected to a welding operation, the method comprising: Providing a device according to any one of claims 1 to 13; controlling the tool including the bending tool assembly to move along the first direction to simultaneously bend a plurality of electrical terminals of a plurality of battery cells arranged along the second direction across the plurality of battery modules among the plurality of battery cells as a preparatory step for welding the electrical terminals of the plurality of battery cells to respective electrical connection elements and / or welding the electrical terminals to each other, and then to maintain the plurality of electrical terminals in a bent state; welding the element via the welding head transportable by the tool along the first direction and the second direction; A method comprising:

15. A method for checking the quality of the welding performed via an apparatus for assembling the battery pack, in which the battery modules, including the battery cells arranged along the first direction, are arranged along the second direction, each of the battery cells having an electrical terminal which must be subjected to a welding operation, the method comprising: providing an apparatus as claimed in claim 1, comprising an automatic control system for checking the quality of the weld performed via the welding head, the automatic control system comprising at least one thermal camera configured to check the quality of a weld bead in a welding area; controlling the automatic control system to automatically check the quality of the weld to analyze the quality of the weld performed by the weld head in real time while the weld head proceeds to weld the electrical terminal; A method comprising:

16. The automatic control system for checking the quality of the weld comprises a first thermal camera and a second thermal camera configured to provide an image in which a value of each pixel identifies a temperature of a respective spot of a welded area so as to estimate the quality of the weld performed, the method comprising: controlling one of the first thermal camera and the second thermal camera such that the one of the first thermal camera and the second thermal camera is always aligned with a position where the welding head is located to perform the welding; controlling the other of the first and second thermal cameras to a further rearward position, the further rearward position being aligned with a previous position of the welding head such that the first and second thermal cameras at the rearmost positions control a cooling phase of the weld bead after performing the welding; The method of claim 15 further comprising:

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