Method for producing a welded connection and battery component system

Abstract

The invention relates to a method for producing a welded connection (36) between a first battery component (12) and a second battery component (14) by means of a laser machining station (10). The method comprises: arranging the first battery component (12) and the second battery component (14) relative to one another so as to form a lap joint or a butt joint; cleaning an irradiation surface (38) by means of a cleaning laser beam (20) of the laser machining station (10), wherein the cleaning laser beam (20) propagates along a cleaning beam path (40); and producing the welded connection (36) by irradiating the irradiation surface (38) by means of a welding laser beam (46) of the laser machining station (10), wherein the welding laser beam (46) propagates along a welding beam path (48). The cleaning beam path (40) is guided during the cleaning of the irradiation surface (38), and the welding beam path (48) is guided during the production of the welded connection (36), via at least one common optical element (24, 28) of a beam guidance device (22) of the laser machining station (10).

Description

[0001] Title: Method for producing a welded joint and

[0002] Battery component system

[0003] Description

[0004] The invention relates to a method for producing a welded joint and a battery component system.

[0005] Typically, two battery components are joined using a weld. Often, the weld also serves as an electrical connection between the two battery components. Frequently, a surface to be irradiated with a laser beam during the welding process is cleaned before the weld is made. This reduces dirt or grime on the irradiation surface, preventing it from entering the weld during the welding process. If dirt or grime does enter the weld, it can unintentionally reduce its mechanical stability and / or increase its electrical resistance.

[0006] CN 208256816 U describes an automated welding workstation for battery modules, comprising a transport system for conveying a battery module to be welded, a laser cleaning device arranged sequentially along the direction of travel of the transport system, a laser welding device, and a detection device. The laser cleaning device is located at one entrance of the transport system. The laser welding device is located on both sides of the transport system and between the laser cleaning device and the detection device.

[0007] The invention aims to provide a method for producing a welded joint and a battery component system, each of which enables the production of a welded joint with high mechanical stability, in particular high strength, and low electrical resistance.

[0008] The invention solves this problem by providing a method with the features of claim 1 and a battery component system with the features of claim 10. Advantageous embodiments and further developments of the invention are set forth in the dependent claims.

[0009] A method according to the invention is designed for producing a welded joint between a first battery component and a second battery component using a laser processing station. The method comprises: arranging the first battery component and the second battery component relative to each other, forming an overlap or butt joint; cleaning an irradiation surface using a cleaning laser beam from the laser processing station, wherein the cleaning laser beam propagates along a cleaning beam path; and producing the welded joint using a welding laser beam from the laser processing station, wherein the welding laser beam propagates along a welding beam path.The cleaning beam path is guided through a common optical element of a beam guidance device of the laser processing station during the cleaning of the irradiation surface and the welding beam path is guided through a common optical element of a beam guidance device of the laser processing station during the creation of the weld connection.

[0010] By guiding the cleaning and welding beam paths over the same optical element of the beam guidance system, cleaning and welding can be performed without changing the position of the two battery components. This eliminates the need to transport the two battery components from a cleaning station to a welding station, thus reducing the time between cleaning and welding. This reduced time significantly reduces the amount of dirt or grime that can accumulate on the cleaned irradiated surface. Another benefit of the shorter time is that the cleaned irradiated surface has a thinner oxide layer at the time of welding.In particular, the reduced dirt or grime and / or oxide layer enables the production of a particularly stable weld joint with low electrical resistance. Specifically, the reduced dirt or grime and / or oxide layer allows for the creation of a stable weld joint with low electrical resistance using a pulsed laser beam. Another advantage of the process is that cleaning the irradiation surface and creating the weld joint can be performed in a single processing station. This reduces non-productive time, especially transport time, thereby shortening the overall production time for the weld joint and increasing productivity.

[0011] Another aspect of the process is that by cleaning the irradiated surface and producing the weld joint in a single processing station, no costs or effort are incurred for a further processing system.

[0012] The welded joint can be formed as a weld seam or a weld spot.

[0013] The irradiation area can be a section of a surface of the first battery component and / or a section of a surface of the second battery component. The irradiation area can be an area that is irradiated with the welding laser beam during the welding process, particularly for the purpose of introducing heat into the two battery components and / or for the purpose of locally melting the two battery components.

[0014] At least one of the two battery components can be a battery terminal and / or an electrical conductor, in particular a busbar. For example, the first battery component can be a battery terminal and the second battery component can be an electrical conductor, in particular a busbar. Each of the two battery components can be designed to conduct electrical current.

[0015] The first battery component and / or the second battery component can be made of a metallic material, preferably iron-based, aluminum-based, or copper-based. The first battery component and the second battery component can be made of the same material or of different materials.

[0016] The first battery component and / or the second battery component can each have a thickness in the range of 6 pm (micrometers) to 3 mm (millimeters).

[0017] If the two battery components are positioned relative to each other in a lap joint, the weld can be created using a deep penetration welding process. During deep penetration welding, one battery component can be welded into the other. If the two battery components are positioned relative to each other in a butt joint, the weld can be created by melting adjacent areas of the two battery components. This allows molten material from the first battery component and molten material from the second battery component to mix together.

[0018] The irradiation surface can be cleaned by irradiating it with a cleaning laser beam. This removes dirt, grime, and / or any existing oxide layer, resulting in a uniform surface finish and / or cleanliness.

[0019] For example, cleaning can roughen and / or structure the irradiation surface. This can improve and / or homogenize the absorption properties of the irradiation surface.

[0020] The weld joint can be created by irradiating the surface with a welding laser beam. This irradiation melts the material of the first battery component and the material of the second battery component, causing them to mix and solidify to form the weld joint.

[0021] In other words, the treatment area can be irradiated successively with the cleaning laser beam and the welding laser beam. Specifically, the treatment area can be irradiated with the cleaning laser beam once, twice, or several times. After cleaning, the treatment area can be irradiated again with the welding laser beam.

[0022] The cleaning blast path and the welding blast path can be the same, at least in sections. In particular, the course of the cleaning blast path and the course of the welding blast path can be the same, at least in sections.

[0023] The laser processing station can include a laser beam source unit for generating the cleaning laser beam and the welding laser beam. The laser beam source unit can include a first laser beam source for generating the cleaning laser beam and a second laser beam source for generating the welding laser beam. The first laser beam source and the second laser beam source can be configured separately, in particular independently of each other.

[0024] Each laser beam source in the laser beam source system can be configured as a solid-state laser. The solid-state laser can be configured as a rod laser, disk laser, or fiber laser.

[0025] The cleaning laser beam and the welding laser beam can each have beam parameters that are the same or different from each other.

[0026] The cleaning laser beam and / or the welding laser beam can each be designed as a continuous-wave laser beam or as a pulsed laser beam.

[0027] If the cleaning laser beam or the welding laser beam is configured as a pulsed laser beam, its pulses can each have a pulse energy in the range of 0.1 mJ (millijoules) to 10 mJ, in particular 0.5 mJ to 2 mJ. Preferably, the pulses can each have a pulse energy in the range of 0.1 mJ (millijoules) to 10 mJ, in particular 0.5 mJ to 2 mJ, if the pulse duration of the cleaning laser beam or the welding laser beam is in the range of 1 ns (nanosecond) to 1000 ns.

[0028] If the cleaning laser beam or the welding laser beam is designed as a pulsed laser beam, its average power can be in the range of 40 W (watts) to 1000 W, particularly 50 W to 500 W. In particular, an average power in the range of 50 W to 80 W may be particularly suitable for spot welding thin films, and an average power in the range of 80 W to 400 W may be particularly suitable for producing a weld seam.

[0029] If the cleaning laser beam or the welding laser beam is configured as a continuous-wave laser beam, its power can be less than or equal to 3000 W. Preferably, the cleaning laser beam or the welding laser beam can then also be configured as a single-mode laser beam.

[0030] The pulse repetition rate of the pulsed cleaning laser beam and / or the pulsed welding laser beam can be in the range of 1 kHz (kilohertz) to 4 MHz (megahertz). The cleaning laser beam and / or the welding laser beam can each have a wavelength of 800 nm to 1200 nm, in particular 1030 nm, 1064 nm, or 1070 nm. Alternatively, the cleaning laser beam and / or the welding laser beam can each have a wavelength of 500 nm to 550 nm, in particular 515 nm.

[0031] The cleaning laser beam and / or the welding laser beam can each have a diffraction coefficient M. 2 of equal to or less than 2, particularly in the range of 1 to 1.6. Alternatively, the cleaning laser beam and / or the welding laser beam can each have a diffraction coefficient M. 2The laser beam should have a amplitude of less than or equal to 12. Preferably, the cleaning laser beam and / or the welding laser beam can each be configured as a single-mode laser beam or a multi-mode laser beam.

[0032] A cross-section of the cleaning laser beam and / or a cross-section of the welding laser beam can each exhibit a Gaussian intensity profile or a top-hat intensity profile. Advantageously, this allows for targeted melting and / or vaporization of the irradiated surface.

[0033] The beam guidance device can be configured to guide the cleaning laser beam and the welding laser beam from the laser beam source device to the two battery components. The beam guidance device can include multiple mirrors for deflecting the cleaning laser beam and the welding laser beam, multiple fiber optic cables for guiding the cleaning laser beam and the welding laser beam via waveguides, and / or multiple lenses for focusing the cleaning laser beam and the welding laser beam.

[0034] The beam guidance device can include a scanner optic, a flying optic, or a processing head over which the cleaning laser beam and / or the welding laser beam are guided. The scanner optic, flying optic, or processing head can be configured to guide the cleaning laser beam and / or the welding laser beam over the two battery components. Advantageously, the scanner optic allows the cleaning laser beam and / or the welding laser beam to be guided over the irradiation surface at high speed.

[0035] For example, the scanner optics can include a deflecting mirror over which the cleaning laser beam and / or the welding laser beam are guided. The deflecting mirror can be arranged in a housing of the scanner optics. The housing can have an opening, in particular a single opening. Preferably, the opening can face the two battery components. The deflecting mirror can be configured to direct the cleaning laser beam and the welding laser beam onto the opening. The cleaning beam path can be guided over the deflecting mirror and through the opening during cleaning of the irradiation surface, and the welding beam path can be guided through the opening during the creation of the weld.

[0036] The beam guidance device can be configured to focus the cleaning laser beam and / or the welding laser beam onto the irradiation surface. The position of the focus of the cleaning laser beam relative to the irradiation surface can differ from the position of the focus of the welding laser beam relative to the irradiation surface. Advantageously, by adjusting the position of the focuses relative to the irradiation surface, a fluence can be set at which the irradiation surface is irradiated with either the cleaning laser beam or the welding laser beam.

[0037] The beam diameter of the cleaning laser beam and / or the welding laser beam on the irradiation surface can each have a value in the range of 20 pm to 500 pm. If the cleaning laser beam or the welding laser beam is configured as a single-mode laser beam, the beam diameter on the irradiation surface can preferably have a value in the range of 20 pm to 70 pm. If the cleaning laser beam or the welding laser beam is configured as a multi-mode laser beam, the beam diameter on the irradiation surface can preferably have a value in the range of 70 pm to 300 pm.

[0038] The beam guidance system can have multiple shared optical elements. Each shared optical element of the beam guidance system can be used to direct the cleaning beam path during cleaning of the irradiated surface and the welding beam path during welding.

[0039] The method can include: detecting the actual machining position during cleaning the irradiation surface and / or during welding; and controlling the machining position to a predetermined target machining position based on the detected actual machining position. Advantageously, this allows for tolerance compensation, higher precision, and reduced scrap. In particular, the detection and control of the actual machining position can make the method suitable for automated welding.

[0040] Detecting the current processing position can involve taking a photo or video, particularly a live stream, using a camera and analyzing the image. The photo or video can contain the current processing position and / or a marker position.

[0041] The method can include: measuring the actual distance between the beam guidance device, in particular the common optical element, and the irradiation surface; and controlling the position of the focus of the cleaning laser beam and / or the focus of the welding laser beam relative to the irradiation surface to a predetermined target position based on the measured actual distance. Advantageously, this allows for high contour accuracy, especially if the irradiation surface is not flat.

[0042] The actual distance can be measured by measuring capacitance. Alternatively, the actual distance can be measured using optical coherence tomography or laser triangulation.

[0043] In particular, a distance of the focus of the cleaning laser beam and / or a distance of the focus of the welding laser beam from the beam guidance device, especially the common optical element, can be specified.

[0044] Another aspect of the process is that the cleaning of the irradiation surface and the creation of the weld connection are carried out using the same components of the laser processing station, in particular the laser beam source, optics and / or sensors.

[0045] In a further development of the process, the procedure comprises: placing the two battery components at a processing point within a work area of ​​the laser processing station. Cleaning the irradiation surface and creating the weld joint are performed while the two battery components are positioned at the processing point. Advantageously, this eliminates the need for transport between cleaning the irradiation surface and creating the weld joint. In a further development of the process, the common optical element is designed as a lens or a curved mirror and is configured to focus the cleaning laser beam and the welding laser beam onto the two battery components, particularly onto the irradiation surface.Alternatively, the common optical element is designed as a waveguide and configured to guide the cleaning laser beam and the welding laser beam, particularly by means of waveguides. Alternatively, the common optical element is designed as an aperture through which the cleaning beam path passes during cleaning of the irradiation surface and the welding beam path passes during welding. Advantageously, this allows for a reduction in a number of costly components of the laser processing station.

[0046] The waveguide can therefore be designed as an optical fiber. The waveguide can be configured to guide the cleaning laser beam and the welding laser beam from the laser beam source device to the irradiation surface.

[0047] The aperture can be an opening in the laser processing station from which the cleaning laser beam emerges during the cleaning of the irradiation surface and the Swiss laser beam emerges during the welding process. The aperture can be circular. The aperture can have a diameter ranging from 0.5 cm (centimeters) to 15 cm, particularly from 1 cm to 10 cm.

[0048] In a further development of the process, the weld joint is created after cleaning the irradiated surface with a time delay of less than or equal to 100 ms, in particular less than or equal to 10 ms. Advantageously, this allows very little dirt or grime to accumulate on the irradiated surface and / or prevents the formation of a thick oxide layer before the weld joint is created.

[0049] In a further development of the process, the cleaning laser beam and the welding laser beam are generated using the same laser beam source in the laser processing station. This advantageously reduces the number of laser beam sources required, thereby saving costs for the laser processing station. Specifically, the cleaning laser beam and the welding laser beam can be generated using a single laser beam source in the laser processing station. This laser beam source can constitute the laser beam source assembly. In other words, the laser beam source assembly can have a single laser beam source. The laser beam source can be designed as a modulating laser beam source for generating the cleaning laser beam and the welding laser beam with different beam parameters.The switching time of the single laser beam source between the cleaning laser beam and the welding laser beam can be less than 100 ms (milliseconds), in particular 10 ms.

[0050] In a further development of the process, the cleaning laser beam and the welding laser beam are guided to the two battery components using the same beam guidance system. This advantageously allows for further cost savings on beam guidance system components. Furthermore, it allows for a particularly compact design of the laser processing station.

[0051] In a further development of the method, at least one section of the cleaning beam path and one section of the welding beam path outside the working area of ​​the laser processing station have the same path. Advantageously, this allows the same components of the beam guidance system to be used for guiding the cleaning laser beam and the welding laser beam to the irradiation surface. In particular, the section can extend from the laser beam source to the working area.

[0052] In a further development of the process, the laser processing station features a sensor for monitoring the cleaning of the irradiation surface and the creation of the weld joint. The process includes: monitoring the cleaning of the irradiation surface using the sensor and / or monitoring the creation of the weld joint using the sensor. Advantageously, this allows for the timely detection and correction of insufficient cleaning of the irradiation surface and / or a defective weld joint. This results in a higher quality weld joint.

[0053] For example, if there is heavily adhering dirt, a single pass of the cleaning laser beam over the irradiation surface may not be sufficient. In this case, the sensor can detect insufficient cleaning of the irradiation surface, causing the cleaning laser beam to pass over it a second time. Similarly, a weld may have a welding defect. This defect can be detected by the sensor. To correct the defect, the faulty weld can be treated with the welding laser beam.

[0054] The sensor can, for example, be designed as a camera.

[0055] In a further development of the process, the welding laser beam is a pulsed laser beam whose laser pulses have a pulse duration of less than 5 ms, in particular 1 ps (microsecond). Additionally or alternatively, the cleaning laser beam is a pulsed laser beam whose laser pulses have a pulse duration of less than 5 ms, in particular 1 ps. Such pulse durations have proven particularly advantageous for cleaning and for creating the weld. Advantageously, this allows high intensities to be achieved at moderate average powers, resulting in targeted heat input at the irradiation surface.

[0056] In particular, the pulse duration of the cleaning laser beam and / or the pulse duration of the welding laser beam can have a value in the range of 1 ns to 5 ms, especially 50 ns to 500 ns.

[0057] A battery component system according to the invention comprises a first battery component, a second battery component, and a laser processing station for producing a welded joint between the first and second battery components. The laser processing station has a working chamber, a laser beam source device, and a beam guidance device. The two battery components are arranged in the working chamber for producing the welded joint. The laser beam source device is configured to generate a cleaning laser beam for cleaning an irradiation surface and a welding laser beam for producing the welded joint. The beam guidance device is configured to direct the cleaning laser beam and the welding laser beam onto the two battery components. The beam guidance device has at least one common optical element.The cleaning laser beam propagates along a cleaning beam path, and the welding laser beam propagates along a welding beam path. The common optical element is arranged such that the cleaning beam path and the welding beam path are guided over the common optical element. The battery component system is specifically designed and configured to execute the previously described process. The previously given description of the process can also apply to identical or functionally equivalent features of the laser processing station.

[0058] The laser processing station may include a control unit. The control unit may include an electronic computing unit, in particular a computer and / or a microcontroller.

[0059] The control unit can be designed to control the beam guidance device and thereby guide the cleaning laser beam or the welding laser beam over the two battery components.

[0060] The control unit can be configured to control the laser beam source device to generate the cleaning laser beam or the welding laser beam.

[0061] Further advantages and advantageous embodiments of the invention can be seen from the figures, their description, and the claims. All features disclosed in the figures, their description, and the claims can be essential to the invention, both individually and in any combination. The figures show:

[0062] Fig. 1 shows a schematic representation of a laser processing station during the cleaning of an irradiation surface, and

[0063] Fig. 2 is a schematic representation of the laser processing station of Fig. 1 during the production of a weld joint.

[0064] Fig. 1 shows a laser processing station 10. The laser processing station 10 is designed to produce a welded connection between a first battery component 12 and a second battery component 14.

[0065] In the illustrated embodiment, the first battery component 12 is an electrical conductor in the form of a busbar, and the second battery component 14 is a battery terminal. The battery terminal is mechanically and electrically connected to the busbar by means of a welded connection so that electrical current can be conducted to or from the battery terminal via the busbar. Both battery components 12 and 14 are made of a metallic material. The material of the first battery component 12 is copper-based, and the material of the second battery component 14 is iron-based.

[0066] The two battery components 12, 14 are arranged relative to each other in a lap joint. In an alternative embodiment, not shown, the two battery components can be arranged relative to each other in a butt joint.

[0067] The two battery components 12, 14 are arranged in a work chamber 16 of the laser processing station 10 for producing the welded joint. Thus, the two battery components 12, 14 together with the laser processing station 10 form a battery component system 100.

[0068] The laser processing station 10 has a laser beam source unit 18. The laser beam source unit 18 consists of a single laser beam source. This single laser beam source is configured to generate a cleaning laser beam 20 and a welding laser beam. The laser beam source is a modulatable fiber laser designed to generate the cleaning laser beam and the welding laser beam with different beam parameters. The switching time of the fiber laser for switching between the cleaning laser beam and the welding laser beam can be less than 100 ms, in particular 10 ms.

[0069] The cleaning laser beam 20 and the welding laser beam differ in their beam parameters. Both the cleaning laser beam 20 and the welding laser beam are pulsed laser beams. The pulse duration of the cleaning laser beam 20 and the pulse duration of the welding laser beam each range from 1 ns to 1000 ns. The pulse duration of the cleaning laser beam 20 and the pulse duration of the welding laser beam can be the same or different.

[0070] The pulse energy of the cleaning laser beam 20 can be lower than the pulse energy of the welding laser beam. The average power of the cleaning laser beam 20 can also be lower than the average power of the welding laser beam. A cross-section of the cleaning laser beam 20 and a cross-section of the welding laser beam each exhibit a Gaussian intensity profile. The cleaning laser beam 20 and the welding laser beam are each single-mode laser beams.

[0071] The laser processing station 10 has a beam guidance device 22. The beam guidance device 22 is designed to direct the cleaning laser beam 20 and the welding laser beam onto the two battery components 12, 14.

[0072] The beam guidance device 22 has a waveguide 24 in the form of an optical fiber and a scanner optic 26. The waveguide 24 is configured to guide the cleaning laser beam 20 and the welding laser beam from the laser beam source device 18 to the scanner optic 26. The scanner optic 26 is configured to direct the cleaning laser beam 20 and the welding laser beam onto the two battery components 12 and 14.

[0073] The scanner optics 26 have a deflecting mirror 28. The deflecting mirror 28 is a movable mirror, for example, a mirror movable by means of a galvanometer drive. The deflecting mirror 28 has a curved mirror surface which is designed to focus the cleaning laser beam 20 and the welding laser beam onto the two battery components 12, 14.

[0074] The deflecting mirror 28 is arranged in a housing 30 of the scanner optics 26. The housing 30 has an opening 32. The opening 32 faces the working chamber 16, in particular the two battery components 12, 14 arranged in the working chamber 16. The deflecting mirror 28 is configured to direct the cleaning laser beam 20 and / or the welding laser beam onto the opening 32. After the cleaning laser beam 20 or the welding laser beam has passed through the scanner optics 26, the cleaning laser beam 20 or the welding laser beam exits the opening 32.

[0075] The laser processing station 10 has a control unit 34 in the form of a computer. The control unit 34 is designed to control the beam guidance device 22, in particular the deflecting mirror 28, and thereby guide the cleaning laser beam 20 or the welding laser beam over the two battery components 12, 14.

[0076] Additionally, the control unit 34 is configured to control the laser beam source device 18 such that the laser beam source device 18 generates the cleaning laser beam 20 or the welding laser beam. In the embodiment shown in Fig. 1, a weld joint in the form of a weld seam 36 is to be produced. The weld seam 36 to be produced is shown as a dotted line in Fig. 1. To produce the weld seam 36, an irradiation area 38 is to be irradiated with the welding laser beam for the purpose of locally melting the two battery components 12, 14. The irradiation area 38 is a surface section of a surface of the first battery component 12.

[0077] To produce the weld seam 36, the control unit 34 controls the laser beam source device 18 such that it generates the cleaning laser beam 20. The cleaning laser beam 20 is shown as a dashed line in Fig. 1. The cleaning laser beam 20 propagates along a cleaning beam path 40.

[0078] The cleaning laser beam 20 is guided from the laser beam source device 18 to the scanner optics 26 by means of the waveguide 24. The cleaning beam path 40 is guided via the deflecting mirror 28 and the aperture 32.

[0079] The control unit 34 controls the beam guidance device 22 such that the cleaning laser beam 20 is directed by means of the deflecting mirror 28 onto the first battery component 12, in particular the irradiation surface 38. The cleaning laser beam 20 is guided over the irradiation surface 38 by controlling the deflecting mirror 28 by means of the control unit 34. This results in the cleaning of the irradiation surface 38 by means of the cleaning laser beam 20, whereby dirt, grime and an oxide layer of the first battery component 12 are locally removed, in particular from the irradiation surface 38.

[0080] Additionally, cleaning roughens the irradiation surface 38, thereby increasing the absorption of the welding laser beam by the first battery component 12.

[0081] Fig. 1 shows the laser processing station 10 during cleaning. The cleaning of the irradiation surface 38 takes place while the two battery components 12, 14 are placed at a processing point 42 within the working area 16.

[0082] The cleaning of the irradiation surface 38 is monitored by a sensor 44 in the form of a camera on the laser processing station 10. For this purpose, the camera 44 takes photographs during the cleaning process, which are then evaluated by the control unit 34. If, based on the evaluation of the photographs, the control unit 34 determines that the irradiation surface 38 is insufficiently cleaned after a pass with the cleaning laser beam 20, the control unit 34 initiates another pass over the irradiation surface 38 with the cleaning laser beam 20.

[0083] Additionally, during the cleaning of the irradiation surface 38, the control unit 34 can detect the actual processing position of the cleaning laser beam 20 using the sensor 44. Based on the detected actual processing position of the cleaning laser beam 20, the control unit 34 can adjust the processing position to a predefined target processing position.

[0084] After cleaning the irradiation surface 38, the control unit 34 controls the laser beam source device 18 such that the laser beam source device 18 generates the welding laser beam. The switch from the cleaning laser beam 20 to the welding laser beam occurs with a time delay of less than 100 ms, in particular less than 10 ms.

[0085] Fig. 2 shows the laser processing station 10 from Fig. 1 while the laser beam source device 18 generates the welding laser beam 46. The welding laser beam 46 is represented by a solid line in Fig. 2. The welding laser beam 46 propagates along a welding beam path 48.

[0086] The welding laser beam 46 is guided from the laser beam source device 18 to the scanner optics 26 by means of the waveguide 24. The welding beam path 48 is guided via the deflecting mirror 28 and the aperture 32. In particular, the welding laser beam 46 exits the scanner optics 26 through the same aperture 32.

[0087] The control unit 34 controls the beam guidance device 22 such that the welding laser beam 46 is directed by means of the deflecting mirror 28 onto the first battery component 12, in particular the irradiation surface 38. The welding laser beam 46 is guided over the irradiation surface 38 by the control unit 34 by means of the deflecting mirror 28. This melts and mixes the material of the two battery components 12, 14. After the molten material solidifies, the weld seam 36 is formed.

[0088] The welding beam path 48 and the cleaning beam path 40 are each guided via the waveguide 24 and the deflecting mirror 28. Therefore, the waveguide 24 and the deflecting mirror 28 each form a common optical element of the beam guidance device 22, through which the welding beam path 48 and the cleaning beam path 40 are guided. The cleaning laser beam 20 and the welding laser beam 46 are guided to the two battery components 12 and 14 by means of the same beam guidance device 22.

[0089] Furthermore, in the illustrated embodiment shown in Figures 1 and 2, the welding blast path 48 and the cleaning blast path 40 are identical. In particular, the welding blast path 48 and the cleaning blast path 40 have the same course.

[0090] The creation of the weld joint 36 is monitored by the sensor 44. For this purpose, the camera 44 takes photographs during the creation of the weld joint 36, which are evaluated by the control unit 34. If the control unit 34 determines, based on the evaluation of the photographs, that the weld joint 36 has a welding defect, the control unit 34 initiates the welding laser beam 46 to pass over the welding defect.

[0091] Additionally, during the welding process 36, the control unit 34 can detect the actual processing position of the welding laser beam 46 using the sensor 44. Based on the detected actual processing position of the welding laser beam 46, the control unit 34 can adjust the processing position to a predefined target processing position.

[0092] This causes the irradiation area 38 to be successively traversed by the cleaning laser beam 20 and the welding laser beam 46. During the traversal of the irradiation area 38 by the cleaning laser beam 20 and the welding laser beam 46, the two battery components 12, 14 are positioned at the same processing point 42 within the working area 16.

[0093] Since the two battery components 12, 14 are positioned at the same processing station 42 during the cleaning of the irradiation surface 38 and during the creation of the weld 36, transport of the two battery components 12, 14 between the cleaning of the irradiation surface 38 and the creation of the weld 36 can be avoided. This reduces the production time for the creation of the weld 36, thereby increasing the productivity of the laser processing station 10.

Claims

Patent claims 1. Method for producing a welded joint (36) between a first battery component (12) and a second battery component (14) using a laser processing station (10), comprising: Arranging the first battery component (12) and the second battery component (14) in a butt joint or overlap joint relative to each other, cleaning an irradiation surface (38) by means of a cleaning laser beam (20) of the laser processing station (10), wherein the cleaning laser beam (20) propagates along a cleaning beam path (40), and Producing the weld joint (36) by irradiating the irradiation surface (38) using a welding laser beam (46) of the laser processing station (10), wherein the welding laser beam (46) propagates along a welding beam path (48), wherein the cleaning beam path (40) during cleaning the irradiation surface (38) and the welding beam path (48) during producing the weld joint (36) are guided over at least one common optical element (24, 28) of a beam guidance device (22) of the laser processing station (10).

2. Method according to claim 1, wherein the method comprises: placing the two battery components (12, 14) at a processing point (42) within a working space (16) of the laser processing station (10), wherein the cleaning of the irradiation surface (38) and the production of the weld connection (36) are carried out while the two battery components (12, 14) are placed at the processing point (42).

3. A method according to any of the preceding claims, wherein the common optical element (24, 28) is configured as a lens or a curved mirror (28) and is configured for focusing the cleaning laser beam (20) and the welding laser beam (46) onto the two battery components (12, 14), or wherein the common optical element (24, 28) is configured as a waveguide (24) and is configured for guiding the cleaning laser beam (20) and the welding laser beam (46), or wherein the common optical element (24, 28) is designed as an aperture through which the cleaning beam path (40) passes during the cleaning of the irradiation surface (38) and the welding beam path (48) passes during the production of the weld connection (36).

4. Method according to one of the preceding claims, wherein the production of the weld joint (36) after cleaning the irradiation surface (38) takes place with a time delay of less than or equal to 100 ms, in particular less than or equal to 10 ms.

5. Method according to one of the preceding claims, wherein the cleaning laser beam (20) and the welding laser beam (46) are generated by means of the same laser beam source of the laser processing station (10).

6. Method according to one of the preceding claims, wherein the cleaning laser beam (20) and the welding laser beam (46) are guided to the two battery components (12, 14) by means of the same beam guidance device (22).

7. Method according to one of the preceding claims, wherein at least one section of the cleaning beam path (40) and one section of the welding beam path (48) outside the working area (16) of the laser processing station (10) have the same course.

8. Method according to one of the preceding claims, wherein the laser processing station (10) has a sensor (44) for monitoring the cleaning of the irradiation surface (38) and the production of the weld joint (36), wherein the method comprises: monitoring the cleaning of the irradiation surface (38) by means of the sensor (44) and / or monitoring the production of the weld joint (36) by means of the sensor (44).

9. A method according to any of the preceding claims, wherein the welding laser beam (46) is a pulsed laser beam whose laser pulses have a pulse duration of less than 5 ms, and / or wherein the cleaning laser beam (20) is a pulsed laser beam whose laser pulses have a pulse duration of less than 5 ms.

10. Battery component system (100) comprising: a first battery component (12), a second battery component (14), and a laser processing station (10) for producing a welded joint (36) between the first battery component (12) and the second battery component (14), comprising: a working chamber (16) in which the two battery components (12, 14) are arranged for producing the welded joint (36), a laser beam source device (18) configured to generate a cleaning laser beam (20) for cleaning an irradiation surface (38) and a welding laser beam (46) for producing the welded joint (36), a beam guidance device (22) for directing the cleaning laser beam (20) and the welding laser beam (46) onto the two battery components (12, 14), wherein the beam guidance device (22) comprises at least one common optical element (24, 28) shows,wherein the cleaning laser beam (20) propagates along a cleaning beam path (40) and the welding laser beam (46) propagates along a welding beam path (48), wherein the common optical element (24, 28) is arranged such that the cleaning beam path (40) and the welding beam path (48) are guided over the optical element (24, 28).

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