Secondary battery manufacturing apparatus and calibration method thereof

Abstract

Exemplary embodiments provide a secondary battery manufacturing apparatus. The secondary battery manufacturing apparatus includes: a masking jig configured to fix an electrode lead and a bus bar and including first to fourth inner side walls defining an opening exposing the electrode lead and the bus bar; a first beam source configured to generate a welding beam; a second beam source configured to generate an inspection beam; a scanning head configured to guide the welding beam and the inspection beam to the electrode lead and the bus bar; a detector; a processor; and a controller.

Description

Technical Field

[0001] This invention relates to a secondary battery manufacturing apparatus and a calibration method thereof. This application claims the benefit of priority to Korean Patent Application No. 10-2023-0135756, filed on October 12, 2023, the entire contents of which are incorporated herein by reference. Background Technology

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various types of wireless devices, such as mobile phones, laptops, and cordless vacuum cleaners. Recently, the primary use of secondary batteries is shifting from mobile devices to mobility, as the manufacturing cost per unit capacity of secondary batteries has decreased dramatically due to increased energy density and economies of scale, and as the range of battery electric vehicles (BEVs) has increased to levels comparable to those of gasoline-powered vehicles.

[0003] Battery manufacturers are making huge capital expenditures to meet the rapidly growing demand for rechargeable batteries in the mobility sector. Companies are constantly conducting research to increase output and productivity, aiming to maximize the return on invested capital by improving the productivity of each production line. Summary of the Invention

[0004] Technical issues The present invention aims to provide a secondary battery manufacturing equipment with improved productivity and a calibration method thereof.

[0005] Technical solution An exemplary embodiment of the present invention provides a secondary battery manufacturing apparatus. The secondary battery manufacturing apparatus includes: an oscillator configured to generate a processing beam; a scanning head configured to emit the processing beam generated by the oscillator toward a material; a driving device configured to move the scanning head; and a processor configured to determine the position of the focal point of the scanning head, wherein the oscillator includes a built-in sensor configured to sense reflected light as a portion of the processing beam reflected from the material, and the processor is configured to determine the position of the focal point of the scanning head based on a signal generated by the built-in sensor.

[0006] The processor can also be configured to collect the intensity distribution of reflected light based on the signal.

[0007] The processor can be configured to determine the location of the scanning head's focal point based on the intensity distribution of the reflected light.

[0008] The processor can be configured to determine the location of the scanning head's focal point based on the duration of the peak value of the intensity distribution of the reflected light.

[0009] The processor can be configured to determine the location of the scanning head's focal point based on the shape of the intensity distribution of the reflected light.

[0010] The processor can be configured to determine the location of the scanning head's focal point based on the poles of the intensity distribution of the reflected light.

[0011] An exemplary embodiment provides a method for calibrating a secondary battery manufacturing apparatus. The method includes: emitting a processing beam toward a material via a scanning head spaced apart from the material by a first working distance; sensing a first reflected light, the first reflected light being a portion of the processing beam reflected from the material at the first working distance; and determining the position of the focal point of the scanning head based on the intensity distribution of the first reflected light, wherein the first reflected light is sensed by a built-in sensor included in an oscillator configured to generate the processing beam.

[0012] The location of the scanning head's focal point can be determined based on the duration of the peak values ​​in the intensity distribution.

[0013] The location of the scanning head's focal point can be determined based on the shape of the intensity distribution.

[0014] The location of the scanning head's focal point can be determined based on the poles of the intensity distribution.

[0015] The method may further include: moving the scanning head to a second working distance; emitting a processing beam toward the material at the second working distance; and sensing a second reflected light, which is a portion of the processing beam reflected from the material at the second working distance.

[0016] The position of the scanning head's focal point can be determined based on the intensity distribution of the second reflected light.

[0017] A processing beam can be emitted at a first working distance toward a first portion of the material, and at a second working distance toward a second portion of the material spaced apart from the first portion of the material.

[0018] Beneficial effects According to an exemplary embodiment of the present invention, the position of the focal point of the scanning head can be accurately determined. Therefore, the productivity and output of secondary battery manufacturing can be improved.

[0019] The effects achievable by exemplary embodiments of the present invention are not limited to those described above, and those skilled in the art to which the exemplary embodiments of the present invention pertain will clearly derive and understand other effects not described herein from the following description. In other words, those skilled in the art can deduce from the exemplary embodiments of the present invention unintended effects achieved when implementing the exemplary embodiments of the present invention. Attached Figure Description

[0020] Figure 1This is a diagram illustrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0021] Figure 2 It shows Figure 1 The oscillator.

[0022] Figure 3 This is a flowchart of a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0023] Figure 4 This is a diagram illustrating a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0024] Figures 5a to 5d This is a graph used to describe a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment. Detailed Implementation

[0025] In the following, embodiments of the invention will be described in detail with reference to the accompanying drawings. Before describing the embodiments of the invention, the terms or expressions used in this specification and claims should not be construed as limited to those commonly understood or defined in common dictionaries, but should be understood based on the principles of the invention, which the inventors of this application may appropriately define in order to best interpret the invention, and according to the meanings and concepts corresponding to the invention.

[0026] Therefore, the embodiments described herein and the configurations shown in the accompanying drawings are merely examples of the present invention and do not reflect all the technical concepts of the present invention. It should be understood that various equivalents and modifications have been made to replace these configurations as of the filing date of this application.

[0027] When well-known configurations or functions related to the description of the present invention are determined to obscure the subject matter of the invention due to unnecessary details, these configurations or functions will not be described in detail.

[0028] Because embodiments of the invention are provided to explain the invention more fully to those skilled in the art, the shapes, dimensions, etc. of the components shown in the drawings may be shown enlarged, omitted, or schematically for clarity. Therefore, it should not be construed that the dimensions or proportions of the components completely reflect their actual dimensions or proportions.

[0029] (First embodiment) Figure 1 This is a diagram illustrating a secondary battery manufacturing apparatus 100 according to an exemplary embodiment.

[0030] Figure 2 It shows Figure 1 Oscillator 110.

[0031] Reference Figure 1 and Figure 2The secondary battery manufacturing equipment 100 may include an oscillator 110, an optical cable 120, a scanning head 130, a drive device 140, and a controller 150.

[0032] The secondary battery manufacturing equipment 100 can be configured to perform laser welding. As a non-limiting example, the welding performed by the secondary battery manufacturing equipment 100 can be keyhole welding. During keyhole welding, a high-energy-density processing beam PB can be emitted towards the workpiece, and a molten pool and hot molten vapor that pushes the pool apart can be generated. The secondary battery manufacturing equipment 100 can be configured to process (i.e., weld) the frame of a battery module or weld the electrode leads of a battery cell to a busbar.

[0033] Oscillator 110 may be a stimulated emission light amplification radiation (laser) device. Oscillator 110 may be configured to generate a processing beam PB. The processing beam PB may be a laser beam. According to an exemplary embodiment, the processing beam PB may be near-infrared radiation. According to an exemplary embodiment, the wavelength of the processing beam PB may be in the range of about 750 nm to about 2500 nm. According to an exemplary embodiment, the wavelength of the processing beam PB may be about 1070 nm.

[0034] As a non-limiting example, oscillator 110 may be a fiber laser. Based on the above description, those skilled in the art will be able to readily derive embodiments in which oscillator 110 is a solid-state laser device (e.g., a semiconductor laser device, an Nd:YAG laser device, or a titanium (Ti)-sapphire laser device), a liquid laser device (e.g., a dye laser device), or a gas laser device (e.g., a helium-neon laser device, a carbon dioxide laser device, or an excimer laser device).

[0035] The oscillator 110 may include multiple pump diodes 111, a pump coupler 112, a first Bragg grating 113, a second Bragg grating 114, a first optical isolator 115, a second optical isolator 116, an active optical fiber 117, an output port 118, and a built-in sensor 119.

[0036] Pump diode 111 can be configured to generate light based on an external signal and / or power (e.g., an electrical signal and / or power). The number of pump diodes 111 in oscillator 110 can be determined based on the desired intensity of the processed beam PB to be output. That is, as the number of pump diodes 111 increases, the maximum intensity of the processed beam PB can increase. The light generated from pump diode 111 can be collected in feed fiber (or multiple feed fibers) via pump coupler 112. The light collected in the feed fiber can be coupled to active fiber 117. First optical isolator 115 and second optical isolator 116 can be configured to prevent the light from traveling backward.

[0037] Each of the first Bragg grating 113 and the second Bragg grating 114 can be a reflector. Light introduced into the active optical fiber 117 can be reflected and amplified by the first Bragg grating 113 and the second Bragg grating 114, thus generating a processed beam PB. The reflectivity of the second Bragg grating 114 can differ from that of the first Bragg grating 113. The reflectivity of the second Bragg grating 114 can be lower than that of the first Bragg grating 113. Therefore, the processed beam PB passing through the second Bragg grating 114 can be output through the output port 118. The output port 118 can be connected to the optical cable 120 or configured to emit the processed beam PB through free space.

[0038] Built-in sensor 119 can be configured to detect reflected light, which is a portion of the processed beam PB reflected from material MT. The reflected light can be re-intruded onto oscillator 110 via scanning head 130 and detected by built-in sensor 119. Built-in sensor 119 can be interposed between second optical isolator 116 and output port 118, or connected to the waveguide (i.e., optical fiber) of processed beam PB between second optical isolator 116 and output port 118. Built-in sensor 119 can be configured to generate a signal (e.g., an electrical signal) based on the reflected light.

[0039] The processing beam PB generated by oscillator 110 can be coupled to scanning head 130 via optical fiber 120. Alternatively, the processing beam PB can be transmitted to scanning head 130 via free-space optics or optical integrated circuits.

[0040] The scanning head 130 can be configured to emit a processing beam PB toward the material MT. The scanning head 130 can be configured to focus the processing beam PB. Furthermore, the scanning head 130 can be configured to scan the workpiece with the processing beam PB after calibration of the secondary battery manufacturing equipment 100 including the scanning head 130 is completed, in order to process the workpiece.

[0041] The scanning head 130 may include various types of optical elements that allow the emission, scanning, and focusing of the processing beam PB, such as beam splitters, galvanometers, scanning lenses (e.g., F-Theta lenses), dichroic mirrors, splitters, half-wave plates, quarter-wave plates, polarizers, and filters. The focal point of the scanning head 130 may be the focal point of the processing beam PB emitted by the scanning head 130. The focal point of the scanning head 130 may also be a composite focal point of the various types of optical elements included in the scanning head 130. The processing beam PB, coupled to the scanning head 130 via the optical cable 120, may pass through the various types of optical elements in the scanning head 130 and then be focused at the focal point of the scanning head 130.

[0042] The drive unit 140 can be configured to move the scanning head 130. The drive unit 140 may include a servo motor and a linear encoder, and is therefore configured to sense and accurately control the movement of the scanning head 130 (more specifically, the amount of movement of the scanning head 130 in the X-axis direction, the amount of movement of the scanning head 130 in the Y-axis direction, and the amount of movement of the scanning head 130 in the Z-axis direction).

[0043] Here, the X-axis and Y-axis directions can be substantially parallel to the surface of the material MT, and the Z-axis direction can be substantially perpendicular to the surface of the material MT. The X-axis, Y-axis, and Z-axis directions can be substantially perpendicular to each other. The X-axis, Y-axis, and Z-axis directions can be defined based on the surface of the platform supporting the material MT.

[0044] The material MT may contain metallic material. When the processing beam PB is emitted onto the material MT, the material MT may partially melt. The reflected light, as part of the processing beam PB reflected from the material MT, may reach the built-in sensor 119 of the oscillator 110, as described above. The material MT may be a sample used to determine the position of the focal point of the scanning head 130, but is not limited thereto.

[0045] The controller 150 can be configured to control the overall operation of the oscillator 110, the scanning head 130, and the drive unit 140. The controller 150 can be configured to generate signals for controlling the oscillation of the oscillator 110, the chopping frequency of the processed beam PB, the intensity of the processed beam PB, and the drive of the scanning head 130 and the drive unit 140.

[0046] Processor 160 can be configured to analyze the signal generated by built-in sensor 119. More specifically, processor 160 can be configured to collect the intensity distribution of reflected light based on the signal generated by built-in sensor 119. Processor 160 can be configured to determine the position of the focal point of scanning head 130 based on the intensity distribution of reflected light. Processor 160 can also be configured to determine the position of the focal point of scanning head 130 based on the intensity distribution of reflected light and the change in the working distance WD of scanning head 130.

[0047] For example, controller 150 can be configured to generate a signal for controlling the movement of scanning head 130 via drive device 140. To determine the position of the focal point of scanning head 130, scanning head 130 can be moved from the working distance WD of the processing window. Here, the processing window can be a range including the working distance WD when the focal point of scanning head 130 relative to the known processing beam PB is located on material MT. Here, the focal point of scanning head 130 relative to the known processing beam PB can be obtained from product or optical modeling specifications. Optical modeling can be provided based on the volume, density, molar heat capacity, melting point, and metal phase transition energy of material MT as the target metal, and the output of processing beam PB.

[0048] For example, when the working distance WD is 30 mm, the focal point of the known processing beam PB is located on the material MT, and the size of the processing window is approximately ±20 mm, the drive unit 140 can be configured to move the scanning head 130 such that the working distance WD changes within the range of approximately 10 mm to approximately 50 mm. By changing the working distance WD via the drive unit 140, the intensity distribution of reflected light from the processing beam PB can be collected.

[0049] The drive unit 140 can be configured to change the working distance WD of the scanning head 130 at set intervals (i.e., to move the scanning head 130) based on control signals from the controller 150. The set intervals can be in the range of about 0.1 mm to about 1 mm. For example, the drive unit 140 can be configured to change the working distance WD of the scanning head 130 at intervals of about 0.1 mm. As another example, the drive unit 140 can be configured to change the working distance WD of the scanning head 130 at intervals of about 1 mm.

[0050] As a non-limiting example, controller 150 may be a programmable logic controller (PLC). A PLC is a special type of microprocessor-based controller that uses programmable memory to store instructions and implement functions such as logic, sequencing, timing, counting, and arithmetic operations to control machines and processes. PLCs are easy to operate and program. Controller 150 may include a power supply, a central processing unit (CPU), input interfaces, output interfaces, communication interfaces, and storage devices.

[0051] Here, controller 150 and processor 160 can be implemented as hardware, firmware, software, or a combination thereof. For example, controller 150 and processor 160 can be computing devices such as workstation computers, desktop computers, laptop computers, and tablet computers. Controller 150 and processor 160 can be simple controllers, microprocessors, complex processors such as CPUs or GPUs, software-configurable processors, dedicated hardware, or firmware. For example, controller 150 and processor 160 can be implemented by general-purpose computers or dedicated hardware (e.g., digital signal processors (DSPs), field-programmable gate arrays (FPGAs), or application-specific integrated circuits (ASICs)).

[0052] According to some embodiments, the operation of controller 150 and processor 160 can be implemented as instructions stored on a machine-readable medium that are readable and executable by one or more processors. Here, the machine-readable medium can include any device for storing and / or transmitting information in a machine-readable (e.g., computing device) form. For example, the machine-readable medium can include read-only memory (ROM), random access memory (RAM), disk storage media, optical storage media, flash memory devices, electrical, optical, acoustic, or other types of radio signals (e.g., carrier waves, infrared signals, digital signals, etc.) and other signals.

[0053] Firmware, software, routines, and instructions can also be configured to perform the operations described above or the processes described below for controller 150 and processor 160. However, the above description is provided for ease of description only, and it should be understood that the operations described above for controller 150 and processor 160 can be implemented by a computing device, processor, controller, or other means capable of executing firmware, software, routines, instructions, etc.

[0054] Due to tolerances in the optical system, including the oscillator 110, optical cable 120, and scanning head 130, the focal point of the scanning head 130, identified based on product specifications, may differ from the actual focal point of the scanning head 130. According to an exemplary embodiment, a built-in sensor 119 included in the oscillator 110 is used to determine the focal point of the scanning head 130, thus enabling high-precision positioning. The built-in sensor 119 is based on a fiber optic system and is therefore a self-aligning element, which can help reduce the time required for aligning and repositioning the optical system. Here, the alignment of the optical system can be an initial setting for measurement and / or inspection, and its repositioning can be an additional setting for calibrating misalignments caused by thermal vibration. Furthermore, by using the built-in sensor 119, the cost of purchasing additional built-in sensors can be reduced, and the resources (e.g., development resources) required to track the movement of the processing beam PB can be reduced.

[0055] (Second Embodiment) Figure 3 This is a flowchart of a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0056] Figure 4 This is a diagram illustrating a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0057] Figures 5a to 5d This is a graph used to describe a method for calibrating a secondary battery manufacturing apparatus according to an exemplary embodiment.

[0058] Reference Figure 1 and Figure 3 In P110, a processing beam PB can be emitted toward the material MT. The processing beam PB, generated by the oscillator 110, can be emitted toward the material MT via the scanning head 130. The processing beam PB can transfer energy to the material MT, thereby causing a change in the state of the surface of the material MT and the vicinity of the surface of the material MT. For example, the surface of the material MT and the vicinity of the surface of the material MT where the processing beam PB is emitted can melt.

[0059] In P120, reflected light can be detected. The reflected light can be a portion of the processed beam PB reflected from the material MT. The reflected light can be isotropic light, such as scattered light, but is not limited to this. The reflected light can be transmitted to the oscillator 110 via the scanning head 130 and the optical fiber 120. The reflected light can be sensed by the built-in sensor 119 of the oscillator 110.

[0060] In P130, the focal point of the scanning head 130 can be determined based on the intensity distribution of the reflected light. The built-in sensor 119 can generate a signal indicating the intensity of the reflected light. A processor 160 can be connected to the built-in sensor 119. The processor 160 can be configured to collect the intensity distribution of the reflected light based on the signal generated by the built-in sensor 119.

[0061] Reference Figure 1 , Figure 3 and Figure 4 This allows for the repeated execution of steps P110 and P120, as well as the collection of the intensity distribution of reflected light, while the working distance WD is varied. Therefore, as... Figures 5a to 5d As shown, the intensity distribution of multiple reflected lights can be obtained based on the working distance WD.

[0062] For example, the scanning head 130 can be configured to emit a processing beam PB toward a first portion P1 of the material MT at a position spaced apart from the material MT by a first working distance WD1. A first reflected light, which is part of the processing beam PB reflected from the first portion P1 of the material MT, can be sensed by the built-in sensor 119 of the oscillator 110, and a first intensity distribution of the first reflected light can be collected by the processor 160.

[0063] The scanning head 130 can be configured to emit a processing beam PB toward a second portion P2 of the material MT at a position spaced apart from the material MT by a second working distance WD2. A second reflected light, which is part of the processing beam PB reflected from the second portion P2 of the material MT, can be sensed by the built-in sensor 119 of the oscillator 110, and a second intensity distribution of the second reflected light can be collected by the processor 160.

[0064] Due to the surface variations of the first portion P1, optical properties different from those of the untreated portion of material M1 may be exhibited. Therefore, in order to collect the intensity distribution from the second working distance WD2, a processed beam PB can be emitted toward the second portion P2, which is horizontally spaced from the first portion P1 (e.g., in the X-axis direction and / or Y-axis direction).

[0065] The intensity distribution of multiple reflected light rays can include a peak intensity. The optical sensor 119 can saturate at the peak intensity, but the embodiment is not limited to this. Figure 5a , Figure 5c and Figure 5d In the process, after the peak intensity of the reflected light is maintained for a set time, the intensity distribution of the reflected light may decrease. This is because the surface (or vicinity) of the material MT extends beyond the focal point (or focal region) of the scanning head 120 relative to the processing beam PB. Therefore, the state of the surface and vicinity of the material MT will not change, or it will take a long time for the state of the surface and vicinity of the material MT to change.

[0066] therefore, Figure 5a , Figure 5c and Figure 5d The peak values ​​PK1, PK3, and PK4 of the intensity distribution of the reflected light, and their durations PD1, PD3, and PD4, can be relatively long. For example, the durations PD1, PD3, and PD4 can be similar to the duration of the processing beam PB that caused the reflected light.

[0067] In contrast, Figure 5b In this process, the peak duration of the intensity distribution of reflected light can be relatively short. This is because the surface (or vicinity) of the material MT is located at (or in the focal region) of the scanning head 120 relative to the processing beam PB, and therefore melts instantaneously. When the surface of the material MT melts, the reflectivity of the material MT may decrease, resulting in a decrease in the intensity of the reflected light.

[0068] Because the intensity of the reflected light is reduced, Figure 5bThe intensity distribution of the reflected light may include additional poles AP. Here, a pole AP is a point on the graph where the slope is essentially zero. The intensity of the reflected light at pole AP may be lower than that at the peak. These additional poles in the intensity distribution of the reflected light may be caused by the melting of the material MT during the duration of the processed beam PB.

[0069] Therefore, the duration PD2 of the peak value PK2 can be relatively short. For example, the duration PD2 of the peak value PK2 can be less than or equal to about 1 / 2 of the pulse duration of the processed beam PB. For example, the duration PD2 of the peak value PK2 can be less than or equal to about 1 / 3 of the pulse duration of the processed beam PB. For example, the duration PD2 of the peak value PK2 can be less than or equal to about 1 / 4 of the pulse duration of the processed beam PB. Here, the duration of the pulse of the processed beam PB can be defined based on the full width at half maximum (FWHM) and / or the full width at half maximum (FWHM).

[0070] The focal position of the scanning head 130 can be determined based on the intensity distribution of the reflected light. The focal position of the scanning head 130 can also be determined based on the shape of the intensity distribution of the reflected light. The shape of the intensity distribution can include the duration of peaks and the number of poles.

[0071] More specifically, one of the intensity distributions of reflected light collected from multiple working distances WD can be selected, and the working distance WD corresponding to the selected intensity distribution of the reflected light can be determined as the position of the focal point of the scanning head 130.

[0072] For example, the intensity distribution with the shortest peak duration can be selected from the intensity distributions of reflected light collected at multiple working distances WD, and the working distance WD corresponding to the selected intensity distribution of the reflected light can be determined as the position of the focal point of the scanning head 130.

[0073] As another example, an intensity distribution with the maximum number of poles can be selected from the intensity distributions of reflected light collected from multiple working distances WD, and the working distance WD corresponding to the selected intensity distribution of the reflected light can be determined as the location of the focal point of the scanning head 130. Here, a pole is a point on the curve with a slope of zero, and the intensity distribution of the reflected light can have multiple poles (e.g., two poles) as the material MT melts during the duration of the pulse of the reflected light.

[0074] The present invention has been described in more detail above with reference to the accompanying drawings and embodiments. However, the configurations shown in the drawings or embodiments described in this specification are merely embodiments of the present invention and do not reflect all the technical concepts of the present invention. Therefore, it should be understood that various equivalents and modifications have been made to replace these configurations as of the filing date of this application.

Claims

1. A secondary battery manufacturing apparatus, comprising: An oscillator configured to generate a processed beam; A scanning head configured to emit the processing beam generated by the oscillator toward the material; A driving device configured to move the scanning head; as well as A processor configured to determine the position of the focal point of the scanning head. The oscillator includes a built-in sensor configured to sense reflected light, which is a portion of the processed light beam reflected from the material. The processor is configured to determine the position of the focal point of the scanning head based on signals generated by the built-in sensor.

2. The secondary battery manufacturing equipment according to claim 1, wherein, The processor is also configured to collect the intensity distribution of the reflected light based on the signal.

3. The secondary battery manufacturing equipment according to claim 2, wherein, The processor is configured to determine the position of the focal point of the scanning head based on the intensity distribution of the reflected light.

4. The secondary battery manufacturing equipment according to claim 3, wherein, The processor is configured to determine the position of the focal point of the scanning head based on the duration of the peak value of the intensity distribution of the reflected light.

5. The secondary battery manufacturing equipment according to claim 3, wherein, The processor is configured to determine the position of the focal point of the scanning head based on the shape of the intensity distribution of the reflected light.

6. The secondary battery manufacturing equipment according to claim 3, wherein, The processor is configured to determine the position of the focal point of the scanning head based on the poles of the intensity distribution of the reflected light.

7. A method for calibrating secondary battery manufacturing equipment, the method comprising: A processing beam is emitted toward the material via a scanning head spaced a first working distance from the material; Sensing a first reflected light, which is a portion of the processed beam reflected from the material at the first working distance; as well as The position of the focal point of the scanning head is determined based on the intensity distribution of the first reflected light. The first reflected light is sensed by a built-in sensor included in an oscillator configured to generate the processed beam.

8. The method according to claim 7, wherein, The location of the focal point of the scanning head is determined based on the duration of the peak value of the intensity distribution.

9. The secondary battery manufacturing equipment according to claim 7, wherein, The position of the focal point of the scanning head is determined based on the shape of the intensity distribution.

10. The secondary battery manufacturing equipment according to claim 7, wherein, The location of the focal point of the scanning head is determined based on the poles of the intensity distribution.

11. The method of claim 7, further comprising: Move the scanning head to the second working distance; The processing beam is emitted toward the material at the second working distance; as well as Sensing a second reflected light, which is a portion of the processed beam reflected from the material at the second working distance.

12. The method according to claim 11, wherein, The position of the focal point of the scanning head is determined based on the intensity distribution of the second reflected light.

13. The method according to claim 12, wherein, The processing beam is emitted at a first working distance toward a first portion of the material, and at a second working distance toward a second portion of the material spaced apart from the first portion of the material.

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