Apparatus for manufacturing secondary batteries and method for manufacturing secondary batteries using the same

Abstract

According to an exemplary embodiment, a secondary battery manufacturing apparatus is provided, the apparatus including a first beam source configured to generate a welding beam, a second beam source configured to generate an inspection beam, a scanner head configured to direct the welding beam and the inspection beam to a module frame, a servo motor configured to move the scanner head, a detector configured to sense a reflected beam that is a portion of the inspection beam reflected from the module frame, a processor configured to collect assembly line data of the module frame based on an inspection signal generated by the detector, and a controller configured to control the servo motor based on the assembly line data of the module frame.

Description

Technical Field

[0001] The present invention relates to an apparatus for manufacturing a secondary battery and a method for manufacturing a secondary battery using the same.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0084675 filed on July 8, 2022, and Korean Patent Application No. 10-2023-0083907 filed on June 29, 2023, and all the contents disclosed in the documents of the Korean patent applications are included as part of this specification.

Background Art

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as an energy source for various wireless devices such as mobile phones, laptop computers, and wireless vacuum cleaners. In recent years, due to improvements in energy density and economies of scale, the manufacturing cost per unit capacity of secondary batteries has decreased significantly, and as the driving range of BEV (battery electric vehicle) has increased to a level equivalent to that of fuel vehicles, the main application of secondary batteries has shifted from mobile devices to mobility.

[0004] To meet the rapid growth in demand for secondary batteries for mobility, cell manufacturers have endured huge capital expenditures. Each company is increasing productivity per line to maximize the return on invested capital, and various studies for improving yield and productivity are continuing for this purpose.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem to be solved by the technical idea of the present invention is to provide an apparatus for manufacturing a secondary battery with improved productivity and a method for manufacturing a secondary battery using the same.

Means for Solving the Problems

[0006] According to an exemplary embodiment of the present invention for solving the above-mentioned problems, an apparatus for manufacturing a secondary battery is provided. The apparatus includes a first beam source configured to generate a welding beam, a second beam source configured to generate an inspection beam, a scanner head configured to direct the welding beam and the inspection beam toward a module frame, a servo motor configured to move the scanner head, a detector configured to sense a reflected beam which is part of the inspection beam reflected from the module frame, a processor configured to collect assembly line data of the module frame based on an inspection signal generated by the detector, and a controller configured to control the servo motor based on the assembly line data of the module frame.

[0007] The above assembly line data includes the coordinates of the assembly lines of the first and second components of the module frame.

[0008] The above controller is configured to control the servo motor so as to scan the assembly line with the welding beam.

[0009] The above controller is configured to calibrate the weld line based on the above assembly line data.

[0010] The above-mentioned weld lines are the portions of the module frame where scanning of the welding beam is scheduled to take place.

[0011] The controller described above is configured to generate signals for controlling the servo motor and the scanner head to weld the module frame based on the assembly line data described above.

[0012] The scanner head includes a dichroic mirror configured to transmit the welding beam and reflect the inspection beam.

[0013] The optical axes of the welding beam that has passed through the dichroic mirror and the inspection beam that has been reflected by the dichroic mirror overlap at least partially.

[0014] The scanner head described above is configured to direct the inspection beam and the welding beam obliquely toward the module frame.

[0015] According to an exemplary embodiment, a method for manufacturing a secondary battery is provided. The method includes the steps of scanning the module frame with an inspection beam to collect assembly line data, including the coordinates of the assembly lines of a first and second component of the module frame, and welding the first and second components based on the assembly line data.

[0016] The above assembly line data is collected based on the three-dimensional shape of the module frame.

[0017] There is a gap between the first part and the second part. The assembly line is the center line of the gap.

[0018] The step of welding the first and second parts described above involves scanning the module frame with a welding beam based on the assembly line data described above.

[0019] The optical axis of the welding beam and the optical axis of the inspection beam partially overlap.

[0020] The step of welding the first and second parts together includes collecting assembly line data indicating the position of the assembly lines and transmitting the assembly line data to a controller.

[0021] The controller described above is configured to control the movement of the scanner head, which is configured to direct the inspection beam and the welding beam.

[0022] The method further includes calibrating the coordinates of the welding line based on the assembly line data to generate a calibrated welding line.

[0023] The step of welding the first and second components scans the module frame with the welding beam along the calibrated welding line.

Advantages of the Invention

[0024] A method for manufacturing a secondary battery according to an exemplary embodiment of the present invention can collect assembly line data of components based on OCT (Optical Coherence Tomography) and weld a frame based on the assembly line data. OCT determines the three-dimensional shape of the components without error due to surface roughness. Also, by coupling the OCT optical system to the scanner head of the welding beam optical system and minimizing the movement time of such scanner head for autofocusing and inspection of the assembly line, the productivity of the secondary battery can be increased.

[0025] The effects obtained in the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those having ordinary knowledge in the technical field to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects by implementing the exemplary embodiments of the present disclosure can also be derived by those having ordinary knowledge in the technical field from the exemplary embodiments of the present disclosure.

Brief Description of the Drawings

[0026] [Figure 1] It is a drawing showing a secondary battery manufacturing apparatus according to an exemplary embodiment. [Figure 2] It is an exploded perspective view of a module frame. [Figure 3] It is a flowchart for explaining a method for manufacturing a secondary battery according to an exemplary embodiment. [Figure 4] It is a drawing for explaining a method for manufacturing a secondary battery according to an exemplary embodiment. [Figure 5] These are drawings illustrating a method for manufacturing a secondary battery according to an exemplary embodiment. [Figure 6] This is a flowchart illustrating a method for manufacturing a secondary battery according to an exemplary embodiment. [Modes for carrying out the invention]

[0027] Preferred embodiments of the present invention will now be described in detail with reference to the attached drawings. Before that, however, terms and words used herein and in the claims should not be interpreted to be limited to their ordinary or dictionary meanings, but rather to mean and define terms in a manner consistent with the technical idea of ​​the present invention, based on the principle that an inventor may appropriately define the concept of a term in order to best describe his own invention.

[0028] Therefore, the embodiments described herein and the configurations illustrated in the drawings represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention. It should be understood that there are various equivalents and modifications that can substitute for them at the time of filing.

[0029] Furthermore, in describing the present invention, if it is determined that a specific description of a related known configuration or function may obscure the gist of the present invention, such detailed description will be omitted.

[0030] Since embodiments of the present invention are provided to more fully explain the invention to an ordinary person, the shapes and sizes of components in the drawings may be exaggerated, omitted, or illustrated schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect their actual sizes and proportions.

[0031] (First Embodiment) Figure 1 is a drawing showing a secondary battery manufacturing apparatus 100 according to an exemplary embodiment.

[0032] Figure 2 is an exploded perspective view of the module frame MF.

[0033] Referring to Figures 1 and 2, according to an exemplary embodiment, the secondary battery manufacturing apparatus 100 may include a first beam source 110, a scanner head 120, an OCT optical system 130, a processor 140, a controller 150, and a servo motor 160.

[0034] The secondary battery manufacturing apparatus 100 may be configured to process the module frame MF of the battery module BM. The secondary battery manufacturing apparatus 100 may be configured to weld the frame body FB, end plate EP, and top plate TP of the module frame MF to each other. The secondary battery manufacturing apparatus 100 may be configured to perform laser welding.

[0035] The first beam source 110 may be a laser (Light Amplification by Stimulated Emission of Radiation) device. The first beam source 110 may be configured to generate a welding beam WB. The welding beam WB may be a laser beam. According to an exemplary embodiment, the welding beam WB may be near-infrared. According to an exemplary embodiment, the wavelength of the welding beam WB may be in the range of about 750 nm to about 2500 nm. According to an exemplary embodiment, the wavelength of the welding beam WB may be about 1070 nm.

[0036] For example, the first beam source 110 may be a solid-state laser device such as a semiconductor laser device, a neodium-yag (Nd:YAG) laser device, a titanium-sapphire (Ti-Sapphire) laser device, or a fiber optic laser device. Another example is that the first beam source 110 may be a liquid laser device such as a dye laser device. Yet another example is that the first beam source 110 may be a gas laser device such as a helium-neon laser, a carbon dioxide laser, or an excimer laser.

[0037] The welding beam WB generated by the first beam source 110 can be coupled to the scanner head 120. According to an exemplary embodiment, the welding beam WB can be transmitted to the scanner head 120 via one of a free-space optical system, an optical integrated circuit, or a fiber optics system.

[0038] The OCT optical system 130 may include a second beam source 131, a beam splitter 133, a reference mirror 135, a detector 137, a first scanning mirror 138, and a second scanning mirror 139.

[0039] The OCT optical system 130 can be configured to capture a three-dimensional image of the module frame MF. The OCT optical system 130 can be based on a Michelson interferometer. The operation of the OCT optical system can be based on the phase delay between a reference beam RFB and a reflected beam RB. The reflected beam RB may be a portion of the inspection beam IB reflected by the sample (i.e., the module frame MF). The phase delay represents the difference in time of flight between the reflected beam RB and the reference beam RFB, and this time of flight difference may contain information about the three-dimensional image of the module frame MF. By scanning the surface of the module frame MF with the inspection beam IB, a depth profile of a portion of the scanned module frame MF (i.e., the depth along the X and Y coordinates of the module frame MF) can be obtained, thereby capturing a three-dimensional image of the module frame MF.

[0040] The second beam source 131 may be a laser device. The second beam source 131 may be configured to generate an inspection beam IB. The inspection beam IB may be a laser beam. According to an exemplary embodiment, the inspection beam IB may be near-infrared. According to an exemplary embodiment, the wavelength of the inspection beam IB may be in the range of about 750 nm to about 2500 nm. According to an exemplary embodiment, the wavelength of the inspection beam IB may be different from the wavelength of the welding beam WB. According to an exemplary embodiment, the wavelength of the inspection beam IB may be even shorter than the wavelength of the welding beam WB. According to an exemplary embodiment, the wavelength of the inspection beam IB may be about 820 nm.

[0041] According to an exemplary embodiment, the inspection beam IB can be collimated. According to an exemplary embodiment, the inspection beam IB can be parallel light. That is, the inspection beam IB can be non-focusing and non-divergent light. According to an exemplary embodiment, the second beam source 131 may include a collimation lens, or a collimation lens may be interposed between the second beam source 131 and the beam splitter 133.

[0042] The beam splitter 133 may be located on the optical path of the inspection beam IB between the scanner head 120 and the second beam source 131. The inspection beam IB may be transmitted to the beam splitter 133. The beam splitter 133 may be configured to split the inspection beam IB. As a non-limiting example, the beam splitter 133 may be configured to transmit a portion of the inspection beam IB and reflect a portion of the inspection beam IB to generate a reference beam RFB. The reflectance of the beam splitter 133 may be substantially the same as the transmittance of the beam splitter 133, or the reflectance of the beam splitter 133 may be lower than the transmittance of the beam splitter 133.

[0043] The reference beam RFB can be reflected by the reference mirror 135 and transmitted to the detector 137 via the beam splitter 133. The inspection beam IB, having passed through the beam splitter 133, can be coupled to the scanner head 120 via the first scanning mirror 138 and the second scanning mirror 139 in sequence.

[0044] A first scanning mirror 138 may be located in the optical path of the inspection beam IB between the beam splitter 133 and the scanner head 120. A second scanning mirror 139 may be located in the optical path of the inspection beam IB between the first scanning mirror 138 and the scanner head 120. Each of the first scanning mirror 138 and the second scanning mirror 139 may be a Garbo mirror. Each of the first scanning mirror 138 and the second scanning mirror 139 may include a reflective surface and a servo motor configured to drive the reflective surface (e.g., rotationally). By driving the first scanning mirror 138 and the second scanning mirror 139, the module frame MF can be scanned with the inspection beam IB.

[0045] The scanner head 120 may include a dichroic mirror 121, a first scanning mirror 123, a second scanning mirror 124, and lenses 125, 127. The scanner head 120 may be configured to direct the welding beam WB and inspection beam IB towards the module frame MF. This allows the module frame MF to be inspected by the inspection beam IB and welded by the welding beam WB. The scanner head 120 may scan the module frame MF with the welding beam WB and inspection beam IB.

[0046] The inspection beam IB and welding beam WB coupled to the scanner head 120 can be transmitted to a dichroic mirror 121. The dichroic mirror 121 may be in the optical path between the first beam source 110 and the module frame MF. The dichroic mirror 121 may be in the optical path between the second scanning mirror 139 and the module frame MF. The inspection beam IB reflected by the dichroic mirror 121 and the welding beam WB transmitted through the dichroic mirror 121 may have similar (or substantially the same) optical paths. The optical axis of the inspection beam IB reflected by the dichroic mirror 121 and the optical axis of the welding beam WB transmitted through the dichroic mirror 121 may overlap at least partially. This may enable autofocusing of the welding beam WB by the inspection beam IB. The dichroic mirror 121 may include, as a non-limiting example, a distributed Bragg reflector.

[0047] The dichroic mirror 121 may have high transmittance to the welding beam WB. For example, the transmittance of the dichroic mirror 121 to the wavelength band of the welding beam WB may be 90% or more. For example, the transmittance of the dichroic mirror 121 to the wavelength band of the welding beam WB may be 95% or more. For example, the transmittance of the dichroic mirror 121 to the wavelength band of the welding beam WB may be 99% or more.

[0048] The dichroic mirror 121 may have a high reflectivity to the inspection beam IB. For example, the reflectivity of the dichroic mirror 121 for the wavelength band of the inspection beam IB may be 90% or more. For example, the reflectivity of the dichroic mirror 121 for the wavelength band of the inspection beam IB may be 95% or more. For example, the reflectivity of the dichroic mirror 121 for the wavelength band of the inspection beam IB may be 99% or more.

[0049] The inspection beam IB reflected by the dichroic mirror 121 and the welding beam WB transmitted through the dichroic mirror 121 can be irradiated onto the module frame MF after sequentially passing through the first scanning mirror 123, the second scanning mirror 124, and lenses 125, 127. However, the dichroic mirror 121 may also be configured to reflect the welding beam WB and transmit the inspection beam IB. In this case, the dichroic mirror may have high reflectivity for the wavelength band of the welding beam and high transmittance for the wavelength band of the inspection beam.

[0050] The first scanning mirror 123 may be in the optical path of the inspection beam IB and the welding beam WB between the dichroic mirror 121 and the module frame MF. The second scanning mirror 124 may be in the optical path of the inspection beam IB and the welding beam WB between the first scanning mirror 123 and the module frame MF. Each of the first scanning mirror 123 and the second scanning mirror 124 may be a Garbo mirror. Each of the first scanning mirror 123 and the second scanning mirror 124 may include a reflective surface and a servo motor configured to drive the reflective surface (e.g., rotationally). By driving the first scanning mirror 123 and the second scanning mirror 124, the module frame MF can be scanned with the inspection beam IB and the welding beam WB.

[0051] According to exemplary embodiments, the first scanning mirror 123 and the second scanning mirror 124 may be configured to scan the module frame MF with the inspection beam IB in addition to the welding beam WB, thereby allowing the first scanning mirror 138 and the second scanning mirror 139 to be omitted or replaced with non-Garbo mirrors (i.e., non-driven fixed mirrors).

[0052] Lenses 125 and 127 can each be a scanning lens. For example, one of lenses 125 or 127 may be, but is not limited to, an F-Theta scanning lens. One of lenses 125 or 127 may be a flat-field scanning lens or a telecentric F-Theta scanning lens.

[0053] The f-theta lens is the standard lens for Garbo scanner-based laser tooling systems. Its diffraction-limited, multi-element, and air-spaced lens design is optimized for a flat field image plane and low f-theta distortion. The displacement of the output beam in the f-theta lens is equal to f*θ, where θ is the angle of incidence of the input beam and f is the focal length. Therefore, the angular velocities of the input and output beams are directly proportional, which allows for operation of the scanning mirror at a constant angular velocity and simplifies the control system.

[0054] In Figure 1, the inspection beam IB and welding beam WB are shown together for illustrative purposes; however, the inspection beam IB and welding beam WB can also be irradiated onto the module frame MF separately. For example, the module frame MF can be inspected by the inspection beam IB, and then elements of the module frame MF can be welded by the welding beam WB.

[0055] The servo motor 160 and the fixing device 200 may be configured to adjust the relative orientation and position of the scanner head 120 and the module frame MF so that at least one of the inspection beam IB and the welding beam WB is incident on the module frame MF at an oblique angle. The oblique incidence of the welding beam WB can prevent or mitigate spatter induced by the welding beam WB from scattering onto the battery cells, thereby mitigating or preventing damage to the battery cells during processing of the module frame MF.

[0056] The area of ​​the welding beam WB on the module frame MF may differ from the area of ​​the inspection beam IB on the module frame MF. The area of ​​the welding beam WB on the module frame MF may be even larger than the area of ​​the inspection beam IB on the module frame MF. Since the welding beam WB covers a wide area of ​​the module frame MF, it can increase the throughput of the secondary battery manufacturing apparatus 100. Since the inspection beam IB covers a narrow area of ​​the module frame MF (i.e., has a narrow FOV (Field of View)), the resolution of the three-dimensional modeling of the module frame MF by the OCT optical system 130 can be improved.

[0057] The battery module BM may include a module frame MF, a cell stack, and a busbar assembly. The cell stack may include multiple battery cells and multiple separators. The multiple battery cells may include a case electrode assembly, electrolyte, and electrode leads.

[0058] The case may be one of a pouch case, a cylindrical case, or a rectangular case. The electrode assembly may be one of a jelly roll type or a stack type. A jelly roll type electrode assembly may include a winding structure of a positive electrode, a negative electrode, and a separator membrane interposed between them. A stack type electrode assembly may include multiple positive electrodes, multiple negative electrodes, and multiple separator membranes interposed between them, stacked sequentially. The electrode leads may include positive electrode leads and negative electrode leads. The positive electrode lead may be coupled to the positive electrode tab of the electrode assembly, and the negative electrode lead may be coupled to the negative electrode tab of the electrode assembly.

[0059] Multiple separators can prevent swelling of multiple battery cells by horizontally supporting them. According to an exemplary embodiment, the multiple separators may also be a thermal barrier.

[0060] A busbar assembly may include a busbar frame and busbars. Busbars may be external connection terminals for outputting voltage and current to the cell stack and may be coupled to the positive and negative leads of the cell stack. The busbar frame may support the busbars and the electrode leads of the cell stack. The busbar assembly may further include integrated circuits, such as a Cell Management Controller (CMC), mounted on the busbar frame.

[0061] The module frame MF may include a frame body FB, an end plate EP, and a top plate TP. The elements of the battery module BM (i.e., the cell stack and busbar assembly) may be integrated into the module frame MF. The module frame MF may cover the elements of the battery module BM (i.e., the cell stack and busbar assembly). The frame body FB may include a U-shape. The frame body FB may include a bottom and side walls connected to the bottom. The end plate EP and top plate TP may have a substantially plate shape.

[0062] The battery module BM can be loaded onto the fixing device 200. The frame body FB, end plate EP, and top plate TP of the module frame MF can be held in an assembled state by the fixing device 200. With the battery module BM held by the fixing device 200, the module frame MF can be inspected and welded by the secondary battery manufacturing apparatus 100.

[0063] The fixing device 200 may include a stage 210 and a plurality of fixtures 221, 222, 223, and 225. The battery module BM may be loaded onto the stage 210. The frame body FB, end plate EP, and top plate TP of the battery module BM loaded onto the stage 210 may be pressurized by the plurality of fixtures 221, 222, 223, and 225. Fixtures 221 and 222 may pressurize the end plate EP and the frame body FB. Fixture 225 may pressurize the frame body FB and the top plate TP. Fixture 223 may pressurize the side walls of the frame body FB and the top plate TP.

[0064] The reflected beam RB can reach the detector 137 by sequentially passing through lenses 125, 127, the first scanning mirror 123 and the second scanning mirror 124, the dichroic mirror 121, the first scanning mirror 138 and the second scanning mirror 139, and the beam splitter 133.

[0065] The detector 137 may be configured to generate an inspection signal IS based on the reflected beam RB and the reference beam RFB. The detector 137 may include, for example, a CCD (Charge Coupled Device) camera and a CMOS (Complementary Metal Oxide Semiconductor) image sensor. The detector 137 may be configured to transmit the inspection signal IS to the processor 140.

[0066] The processor 140 may be configured to determine the three-dimensional shape of the module frame MF based on the inspection signal IS. The processor 140 may be configured to collect assembly line data ALD. The processor 140 may be configured to determine the assembly lines of the frame body FB and the end plate EP, the assembly lines of the frame body FB and the top plate TP, and the assembly lines of the end plate EP and the top plate TP based on the three-dimensional shape of the module frame MF. The processor 140 may be configured to determine the gap between the frame body FB and the end plate EP, the gap between the frame body FB and the top plate TP, and the gap between the end plate EP and the top plate TP based on the three-dimensional shape of the module frame MF. The processor 140 may be configured to transmit the assembly line data ALD to the controller 150.

[0067] The controller 150 may be configured to control the various operations of the first beam source 110, the scanner head 120, and the servo motor 160. It may be configured to generate signals to control the oscillation of the first beam source 110, the chopping frequency of the welding beam WB, the intensity of the welding beam WB, the driving of the first scanning mirror 123 and the second scanning mirror 124, and the driving of the servo motor 160.

[0068] The controller 150 may be configured to generate signals for controlling the servo motor 160 and the scanner head 120 to weld the module frame MF based on the assembly line data ALD. The controller 150 may also be configured to control the movement of the scanner head 120 by the servo motor 160 and the driving of the first scanning mirror 123 and the second scanning mirror 124.

[0069] As a non-restrictive example, controller 150 could be a PLC (Programmable Logic Controller). A PLC is a special form of microprocessor-based controller that uses programmable memory to store instructions and controls machines and processes by embodying functions such as logic, sequencing, timing, counting, and arithmetic. PLCs are easy to operate and program. Controller 150 may include a power supply, a CPU (Central Process Unit), input interfaces, output interfaces, communication interfaces, and memory devices.

[0070] Here, the processor 140 and controller 150 can be embodied in hardware, firmware, software, or any combination thereof. For example, the processor 140 and controller 150 may be computing devices such as workstation computers, desktop computers, laptop computers, and tablet computers. The processor 140 and controller 150 may be simple controllers, complex processors such as microprocessors, CPUs, and GPUs, processors composed of software, dedicated hardware, or firmware. The processor 140 and controller 150 can be embodied, for example, in general-purpose computers or application-specific hardware such as DSPs (Digital Signal Processors), FPGAs (Field Programmable Gate Arrays), and ASICs (Application Specific Integrated Circuits).

[0071] According to some embodiments, the operation of the processor 140 and the controller 150 may be embodied as instructions stored on a machine-readable medium that can be read and executed by one or more processors. Here, the machine-readable medium may include any mechanism for storing and / or transmitting information in a form readable by a machine (e.g., a computing device). For example, the machine-readable medium may include ROM (Read Only Memory), RAM (Random Access Memory), magnetic disk storage media, optical storage media, flash memory devices, electrical, optical, acoustic or other forms of radio signals (e.g., carrier waves, infrared signals, digital signals, etc.) and any other signals.

[0072] Firmware, software, routines, and instructions may be configured to perform the operations described for processor 140 and controller 150, or any of the processes described below. However, this is for illustrative purposes only, and it should be understood that the operations of processor 140 and controller 150 described above may also originate from other devices that execute computing equipment, processors, controllers, or firmware, software, routines, instructions, etc.

[0073] The servo motor 160 may be configured to move the scanner head 120 in a translational direction. The servo motor 160 may be configured to move the scanner head 120 in a vertical direction (i.e., in the working distance direction). Vertical movement of the scanner head 120 allows the welding beam WB to be focused on the module frame MF. The servo motor 160 may be configured to move the scanner head 120 in a horizontal direction. Horizontal movement of the scanner head 120 allows the assembly lines of the module frame MF to be scanned by the welding beam WB, thereby allowing the frame body FB, end plate EP, and top plate TP of the module frame MF to be welded.

[0074] (Second Embodiment) Figure 3 is a flowchart illustrating a method for manufacturing a secondary battery according to an exemplary embodiment.

[0075] Figure 4 is a drawing illustrating an inspection of a modular frame according to an exemplary embodiment. In Figure 4, the first part P1 may be any one of the frame body FB, top plate TP, and end plate EP of the modular frame MF, and the second part P2 may be any other one of the frame body FB, top plate TP, and end plate EP of the modular frame MF.

[0076] Referring to Figures 1, 3, and 4, at P110, the module frame MF may be scanned with the inspection beam IB to collect assembly line data ALD. More specifically, to collect assembly line data ALD, the assembly lines AL of the first component P1 and the second component P2, and the portions of the first component P1 and the second component P2 adjacent to the assembly lines AL may be scanned with the inspection beam IB. The areas on the module frame MF scanned with the inspection beam IB may include zigzag lines (e.g., triangular waveform lines). The sampling frequency for scanning with the inspection beam IB may be in the range of tens of kHz to hundreds of kHz.

[0077] Here, the assembly line AL may be the boundary line between the first part P1 and the second part P2 of the module frame MF. The assembly line AL may be the profile of the contact surface between the first part P1 and the second part P2 of the module frame MF.

[0078] The Z-field measurement range (i.e., depth measurement limit) of the inspection beam IB can range from a few millimeters to several tens of millimeters. The Z-field measurement range (i.e., depth measurement limit) of the inspection beam IB can range from approximately 3 mm to approximately 12 mm. The resolution in the Z-axis direction of the inspection beam IB can range from approximately 1 μm to approximately 100 μm.

[0079] The diameter of the XY field measurement area (i.e., the horizontal scanning range) of the inspection beam IB can range from a few millimeters to several tens of millimeters. The XY plane resolution of the inspection beam IB can range from approximately 1 μm to approximately 100 μm. Here, the XY plane can be the scanning plane of the inspection beam IB, and the Z axis can be substantially perpendicular to the XY plane.

[0080] An inspection signal IS can be generated by scanning the module frame MF with an inspection beam IB. The processor 140 can determine the three-dimensional shape of the module frame MF based on the inspection signal IS. The processor 140 can be configured to collect assembly line data ALD based on the three-dimensional shape of the module frame MF. The assembly line data ALD may include the coordinates of the assembly line AL. The coordinates of the assembly line AL may be the coordinates on the scanning plane of the module frame MF using the inspection beam IB, and the coordinates of the assembly line AL may include X-direction coordinates and Y-direction coordinates.

[0081] A gap GP may exist between the first part P1 and the second part P2 due to manufacturing errors such as surface roughness, defects, and cracks in the first part P1 and the second part P2, as well as systematic and random errors caused by the fixing device 200. If the reflected beam RB is not detected, or if the depth of a portion of the module frame MF is greater than the critical depth, that portion of the module frame MF may be determined as the gap GP. If the module frame MF has a nonzero gap GP, the assembly line AL may be determined as the centerline of the gap GP (e.g., the widthwise centerline of the gap GP). The processor 140 may be configured to determine the assembly line AL from the gap GP. Contrary to what is shown in Figure 4, the first part P1 and the second part P2 may be ideally assembled, and the width of the gap GP may be zero.

[0082] Next, at P120, the gap GP can be compared with the critical value. If the gap GP exceeds the critical value, at P125, the module frame MF may be reassembled. After the reassembly of the module frame MF, it may be inspected again at P110 to collect the assembly line data ALD.

[0083] Referring to Figures 1, 3, and 5, if the gap (GP, see Figure 4) does not exceed a critical value (i.e., if the gap GP is below the critical value), the coordinates of the weld line WL can be calibrated at P130 based on the assembly line data ALD. The weld line WL can be determined based on a standard model of the module frame MF of the battery module BM loaded into the fixing device 200. The weld line WL may be the portion of the module frame MF where welding is planned, without production and process errors. Production and process errors in the module frame MF may cause a discrepancy between the weld line WL and the assembly line AL. The discrepancy between the weld line WL and the assembly line AL may include inclination and separation, etc. The controller 150 may be configured to calibrate the coordinates of the weld line WL based on the assembly line data ALD to generate a calibrated weld line. Calibration of the weld line WL may include calibrating the coordinates of the weld line WL based on the start and end points of the assembly line AL.

[0084] Next, in P140, the module frame MF may be welded based on the calibrated weld line. Welding the module frame MF may include scanning the module frame MF with a welding beam WB along the calibrated weld line. According to the exemplary embodiment, welding the module frame MF based on the calibrated weld line can prevent unwelded and weakly welded parts of the module frame, thereby increasing the reliability of secondary battery manufacturing.

[0085] Figure 6 is a flowchart illustrating a method for manufacturing a secondary battery according to an exemplary embodiment.

[0086] In Figure 6, the processes of P110 and P120 are substantially the same as those explained with reference to Figures 3 to 5, so their redundant explanations are omitted.

[0087] Referring to Figures 1 and 6, at P131, the module frame MF can be welded based on the assembly line data ALD. In this example, the module frame MF can be scanned directly with the welding beam WB based on the assembly line data ALD without calibrating the weld line WL based on the assembly line data ALD. The controller 150 is configured to perform many calculations in addition to calibrating the weld line WL. By having the controller 150 generate a signal for welding using the assembly line data ALD directly, the computing power of the controller 150 can be reduced, thereby improving process continuity and reliability.

[0088] The present invention has been described in more detail above with reference to the drawings and embodiments. However, the configurations described in the drawings or embodiments described herein are merely one embodiment of the present invention and do not represent the entire technical concept of the present invention. It should be understood that there are various equivalents and modifications that can substitute for them at the time of filing this application. [Explanation of Symbols]

[0089] 100 Secondary battery manufacturing equipment 110 First Beam Source 120 Scanner Heads 121 Dichroic Mirror 123 First Scanning Mirror 124 Second Scanning Mirror 125 lens 127 Lens 130 OCT optical system 131 Second Beam Source 133 Beam Splitter 135 Standard Mirror 137 Detectors 138 First Scanning Mirror 139 Second scanning mirror 140 processors 150 controllers 160 Servo motors 200 Fixation device

Claims

1. A first beam source configured to generate a welding beam, A second beam source configured to generate an inspection beam, A scanner head configured to direct the welding beam and the inspection beam toward the module frame, A servo motor configured to move the scanner head, A detector configured to sense a reflected beam, which is a portion of the inspection beam reflected from the module frame, A processor configured to collect assembly line data of the module frame based on an inspection signal generated by the detector, A controller configured to control the servo motor based on the assembly line data of the module frame, The assembly line data includes the coordinates of the assembly lines of the first and second components of the module frame. The assembly lines of the first and second parts and the portions of the first and second parts adjacent to the assembly lines are scanned with the inspection beam, including the triangular waveform line. The assembly line data is collected based on the three-dimensional shape of the module frame. If there is a gap between the first part and the second part, the assembly line is determined as the widthwise center line of the gap. Secondary battery manufacturing equipment.

2. The controller is configured to control the servo motor to scan the assembly line with the welding beam. The secondary battery manufacturing apparatus according to claim 1.

3. The controller is configured to calibrate the weld line based on the assembly line data, and The aforementioned weld line is the portion of the module frame where scanning of the welding beam is planned. The secondary battery manufacturing apparatus according to claim 1 or 2.

4. The controller is configured to generate signals for controlling the servo motor and the scanner head to weld the module frame based on the assembly line data. The secondary battery manufacturing apparatus according to claim 1 or 2.

5. The scanner head includes a dichroic mirror configured to transmit the welding beam and reflect the inspection beam, The secondary battery manufacturing apparatus according to claim 1 or 2.

6. The optical axes of the welding beam transmitted through the dichroic mirror and the inspection beam reflected by the dichroic mirror overlap at least partially. The secondary battery manufacturing apparatus according to claim 5.

7. The scanner head is configured to direct the inspection beam and the welding beam obliquely to the module frame. The secondary battery manufacturing apparatus according to claim 1 or 2.

8. The steps include scanning the module frame with an inspection beam to collect assembly line data, including the coordinates of the assembly lines of the first and second components of the module frame, A step of welding the first part and the second part based on the data of the assembly line, Includes, In the scanning stage, This includes scanning the assembly lines of the first and second parts and the portions of the first and second parts adjacent to the assembly lines with the inspection beam, including the triangular waveform lines. The assembly line data is collected based on the three-dimensional shape of the module frame. If there is a gap between the first part and the second part, the assembly line is determined as the widthwise center line of the gap. A method for manufacturing rechargeable batteries.

9. The step of welding the first and second parts involves scanning the module frame with a welding beam based on the assembly line data. A method for manufacturing a secondary battery according to claim 8.

10. The optical axis of the welding beam and the optical axis of the inspection beam partially overlap. A method for manufacturing a secondary battery as described in claim 9.

11. The step of welding the first and second parts includes collecting assembly line data indicating the position of the assembly line and transmitting the assembly line data to a controller. The controller is configured to control the movement of the scanner head configured to direct the inspection beam and the welding beam. A method for manufacturing a secondary battery according to claim 8.

12. The further step includes calibrating the coordinates of the weld line based on the assembly line data to generate a calibrated weld line, A method for manufacturing a secondary battery according to claim 11.

13. The step of welding the first and second parts involves scanning the module frame with the welding beam along the calibrated weld line. A method for manufacturing a secondary battery according to claim 12.

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