Apparatus for manufacturing secondary battery and method for manufacturing secondary battery 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 contents disclosed in the documents of said Korean patent applications are incorporated herein by reference. [Background technology]

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for a variety of wireless devices such as handsets, laptops, and wireless vacuum cleaners. In recent years, the manufacturing cost per unit capacity of secondary batteries has dramatically decreased due to improvements in energy density and economies of scale, and as the driving range of BEVs (battery electric vehicles) increases to a level comparable to that of fuel-powered vehicles, the main use of secondary batteries is shifting from mobile devices to mobility.

[0004] To meet the rapid growth in demand for secondary batteries for mobility, cell manufacturers are enduring huge capital expenditures. Each company is increasing productivity per line to maximize the return on invested capital, and therefore various research is ongoing to improve yield and productivity. Summary of the Invention [Problem to be solved by the invention]

[0005] An object 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 problem]

[0006] According to an exemplary embodiment of the present invention for solving the above-mentioned problems, there is provided an apparatus for manufacturing a secondary battery, 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.

[0007] The assembly line data includes assembly line coordinates of a first part and a second part of the module frame.

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

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

[0010] The weld seam is the portion of the module frame that is intended to be scanned by the welding beam.

[0011] The controller is configured to generate signals to control the servo motors and the scanner head to weld a module frame based on the assembly line data.

[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 transmitted through the dichroic mirror and the inspection beam reflected by the dichroic mirror at least partially overlap.

[0014] The scanner head is configured to direct the inspection beam and the welding beam at an angle toward the module frame.

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

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

[0017] A gap exists between the first part and the second part, and the assembly line is a centerline of the gap.

[0018] The step of welding the first part and the second part includes scanning the module frame with a welding beam based on the assembly line data.

[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 components includes collecting assembly line data indicative of a position of the assembly line and transmitting the assembly line data to a controller.

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

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

[0023] The step of welding the first and second components includes scanning the module frame along the calibrated weld line with the welding beam. Effect of the Invention

[0024] The method for manufacturing a secondary battery according to an exemplary embodiment of the present invention may collect assembly line data of parts based on OCT (Optical Coherence Tomography) and weld a frame based on the assembly line data. OCT determines the three-dimensional shape of the parts, but there is no error due to surface roughness. In addition, the OCT optical system is coupled to the scanner head of the welding beam optical system, and the moving time of the scanner head for autofocusing and assembly line inspection can be minimized, thereby improving the productivity of the secondary battery.

[0025] The effects obtained by 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 a person having ordinary skill in the art 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 from the exemplary embodiments of the present disclosure by a person having ordinary skill in the art. [Brief description of the drawings]

[0026] [Figure 1] 1 is a diagram showing an apparatus for manufacturing a secondary battery according to an exemplary embodiment; [Diagram 2] FIG. [Diagram 3] 4 is a flowchart illustrating a method for manufacturing a secondary battery according to an exemplary embodiment. [Figure 4] 1 is a diagram illustrating a method for manufacturing a secondary battery according to an exemplary embodiment; [Diagram 5] 1 is a diagram illustrating a method for manufacturing a secondary battery according to an exemplary embodiment; [Figure 6] 4 is a flowchart illustrating a method for manufacturing a secondary battery according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Before that, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concept of the term to best describe his own invention.

[0028] Therefore, it should be understood that the embodiment described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can replace them at the time of this application.

[0029] In addition, in the description of the present invention, if it is determined that a specific description of related publicly known configurations or functions may obscure the gist of the present invention, the detailed description will be omitted.

[0030] Since the embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, the shapes and sizes of components in the drawings may be exaggerated, omitted, or illustrated roughly for clearer explanation. Therefore, the sizes and proportions of each component do not completely reflect the actual sizes and proportions.

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

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

[0033] 1 and 2, according to an exemplary embodiment, a 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 a module frame MF of a battery module BM. The secondary battery manufacturing apparatus 100 may be configured to weld together a frame body FB, an end plate EP, and a top plate TP of the module frame MF. 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] As an example, the first beam source 110 may be a solid-state laser device such as a semiconductor laser device, a Neodymium YAG laser device, a Ti-Sapphire laser device, or an optical fiber laser device. As another example, the first beam source 110 may be a liquid laser device such as a dye laser device. As another example, 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 may be coupled to the scanner head 120. According to an exemplary embodiment, the welding beam WB may be transmitted to the scanner head 120 via any one of a free space optical system, an optical integrated circuit, and a fiber optic 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 may be configured to capture a three-dimensional image of the module frame MF. The OCT optical system 130 may be based on a Michelson interferometer. The operation of the OCT optical system may be based on a 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 a sample (i.e., the module frame MF). The phase delay indicates a difference in time of flight between the reflected beam RB and the reference beam RFB, which may contain information about the three-dimensional image of the module frame MF. By scanning a surface of the module frame MF with the inspection beam IB, a depth profile (i.e., depth along the X- and Y-coordinates of the module frame MF) of the portion of the scanned module frame MF may be obtained, and thus a three-dimensional image of the module frame MF may be captured.

[0040] The second beam source 131 may be a laser device. The second beam source 131 may be configured to generate the 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 may be collimated. According to an exemplary embodiment, the inspection beam IB may be parallel light. That is, the inspection beam IB may be non-converging light and non-diverging 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 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 the reference beam RFB. The reflectance of the beam splitter 133 may be substantially the same as the transmittance of the beam splitter 133, but is not limited thereto. The reflectance of the beam splitter 133 may be higher than 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] Reference beam RFB may be reflected by reference mirror 135 and transmitted through beam splitter 133 to detector 137. Inspection beam IB transmitted through beam splitter 133 may be coupled into scanner head 120 via first scanning mirror 138 and second scanning mirror 139 in sequence.

[0044] The first scanning mirror 138 may be in the optical path of the inspection beam IB between the beam splitter 133 and the scanner head 120. The second scanning mirror 139 may be 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 galvo 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 (e.g., rotate) the reflective surface. By driving the first scanning mirror 138 and the second scanning mirror 139, the module frame MF may 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 the inspection beam IB to the module frame MF, so that the module frame MF may 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 the inspection beam IB.

[0046] The inspection beam IB and the welding beam WB coupled to the scanner head 120 may be transmitted to the dichroic mirror 121. The dichroic mirror 121 may be in an optical path between the first beam source 110 and the module frame MF. The dichroic mirror 121 may be in an 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 at least partially overlap. This may achieve autofocusing of the welding beam WB by the inspection beam IB. The dichroic mirror 121 may include a distributed Bragg reflector, as a non-limiting example.

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

[0048] Dichroic mirror 121 may have high reflectance for inspection beam IB. For example, the reflectance of dichroic mirror 121 for the wavelength band of inspection beam IB may be 90% or more. For example, the reflectance of dichroic mirror 121 for the wavelength band of inspection beam IB may be 95% or more. For example, the reflectance of dichroic mirror 121 for the wavelength band of 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 may be irradiated onto the module frame MF after sequentially passing through the first scanning mirror 123, the second scanning mirror 124, and the lenses 125 and 127. However, this is not limited thereto, and the dichroic mirror 121 may be configured to reflect the welding beam WB and to transmit the inspection beam IB. In this case, the dichroic mirror may have a high reflectance for the wavelength band of the welding beam and a 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 galvo 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 (e.g., rotate) the reflective surface. By driving the first scanning mirror 123 and the second scanning mirror 124, the module frame MF may be scanned with the inspection beam IB and the welding beam WB.

[0051] According to an exemplary embodiment, 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, whereby the first scanning mirror 138 and the second scanning mirror 139 may be omitted or replaced with non-galvo mirrors (i.e., non-driven fixed mirrors).

[0052] Each of the lenses 125, 127 may be a scanning lens. For example, but not limited to, one of the lenses 125, 127 may be an F-Theta scanning lens. One of the lenses 125, 127 may be a Flat Field scanning lens or a Telecentric F-Theta scanning lens.

[0053] F-theta lenses are the standard lenses for galvo scanner based laser tooling systems. The diffraction limited, multi-element, and air-spaced lens design is optimized for a flat field at the image plane and low f-theta distortion. The output beam displacement of an 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. Thus, the angular velocities of the input and output beams are directly proportional, which allows for constant angular velocity operation of the scanning mirror and simplification of the control system.

[0054] 1, the inspection beam IB and the welding beam WB are illustrated simultaneously for convenience of illustration, but the inspection beam IB and the welding beam WB may be irradiated separately onto the module frame MF. For example, after the module frame MF is inspected by the inspection beam IB, elements of the module frame MF may 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 such that at least one of the inspection beam IB and the welding beam WB is obliquely incident on the module frame MF. The oblique incidence of the welding beam WB may prevent or mitigate spatter induced by the welding beam WB from splashing 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 be different 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, the throughput of the apparatus 100 for manufacturing secondary batteries may be increased. 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 three-dimensional modeling of the module frame MF by the OCT optical system 130 may be improved.

[0057] The battery module BM may include a module frame MF, a cell stack, and a bus bar assembly. The cell stack may include a plurality of battery cells and a plurality of separators. The plurality of battery cells may include a case-electrode assembly, an electrolyte, and an electrode lead.

[0058] The case may be any one of a pouch case, a cylindrical case, and a square case. The electrode assembly may be any one of a jelly roll type and a stack type. The jelly roll type electrode assembly may include a rolled structure of a positive electrode, a negative electrode, and a separator interposed therebetween. The stack type electrode assembly may include a plurality of positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed therebetween, which are stacked in sequence. The electrode lead may include a positive electrode lead and a negative electrode lead. The positive electrode lead may be coupled to a positive electrode tab of the electrode assembly, and the negative electrode lead may be coupled to a negative electrode tab of the electrode assembly.

[0059] The separators may prevent swelling of the battery cells by supporting the battery cells horizontally. According to an exemplary embodiment, the separators may be thermal barriers.

[0060] The busbar assembly may include a busbar frame and a busbar. The busbar may be an external connection terminal for outputting the voltage and current of the cell stack and may be coupled to the positive and negative leads of the cell stack. The busbar frame may support the busbar and the electrode leads of the cell stack. The busbar assembly may further include an integrated circuit 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 the busbar assembly) may be built into the module frame MF. The module frame MF may cover the elements of the battery module BM (i.e., the cell stack and the busbar assembly). The frame body FB may include a U-shape. The frame body FB may include a bottom and a side wall connected to the bottom. The end plate EP and the top plate TP may have an approximately plate shape.

[0062] The battery module BM may be loaded onto the fixing device 200. The frame body FB, end plate EP, and top plate TP of the module frame MF may be maintained in an assembled state by the fixing device 200. With the battery module BM held by the fixing device 200, the module frame MF may 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 jigs 221, 222, 223, 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 pressed by the plurality of jigs 221, 222, 223, 225. The jigs 221, 222 may press the end plate EP and the frame body FB. The jig 225 may press the frame body FB and the top plate TP. The jig 223 may press both side walls of the frame body FB and the top plate TP.

[0064] The reflected beam RB may reach the detector 137 via lenses 125 , 127 , first and second scanning mirrors 123 and 124 , dichroic mirror 121 , first and second scanning mirrors 138 and 139 , and beam splitter 133 in sequence.

[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 charge coupled device (CCD) camera, a complementary metal oxide semiconductor (CMOS) image sensor, etc. 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 a 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 an assembly line between the frame body FB and the end plate EP, an assembly line between the frame body FB and the top plate TP, and an assembly line 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 determine a gap between the frame body FB and the end plate EP, a gap between the frame body FB and the top plate TP, and a 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 general operations of the first beam source 110, the scanner head 120, and the servo motor 160. The controller 150 may be configured to generate signals for controlling 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 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-limiting example, the controller 150 may be a Programmable Logic Controller (PLC). A PLC is a special form of microprocessor-based controller that uses programmable memory to store instructions and implement functions such as logic, sequencing, timing, counting, and arithmetic to control machines and processes. PLCs are easy to operate and program. The controller 150 may include a power supply, a Central Process Unit (CPU), an input interface, an output interface, a communication interface, and a memory device.

[0070] Here, the processor 140 and the controller 150 may be embodied in hardware, firmware, software, or any combination thereof. For example, the processor 140 and the controller 150 may be a computing device such as a workstation computer, a desktop computer, a laptop computer, a tablet computer, etc. The processor 140 and the controller 150 may be a simple controller, a complex processor such as a microprocessor, a CPU, a GPU, a processor configured by software, a dedicated hardware or firmware. The processor 140 and the controller 150 may be embodied by a general-purpose computer or application-specific hardware such as a digital signal process (DSP), a field programmable gate array (FPGA), and an application specific integrated circuit (ASIC), for example.

[0071] In some embodiments, the operations of the processor 140 and the controller 150 may be embodied as instructions stored on a machine-readable medium that may be read and executed by one or more processors. Here, a 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, a machine-readable medium may include a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk storage medium, an optical storage medium, a flash memory device, an electrical, optical, acoustic or other form of radio wave signal (e.g., carrier wave, infrared signal, digital signal, etc.), and any other signal.

[0072] Firmware, software, routines, instructions may be configured to perform the operations described for processor 140 and controller 150 or any of the steps described below, however, this is for convenience of explanation and it should be understood that the operations of processor 140 and controller 150 described above may result from a computing device, processor, controller, or other device executing firmware, software, routines, instructions, etc.

[0073] The servo motor 160 may be configured to translate the scanner head 120. The servo motor 160 may be configured to move the scanner head 120 in a vertical direction (i.e., in the working distance direction). The vertical movement of the scanner head 120 may focus the welding beam WB on the module frame MF. The servo motor 160 may be configured to move the scanner head 120 in a horizontal direction. The horizontal movement of the scanner head 120 may scan the assembly line of the module frame MF with the welding beam WB, thereby welding the frame body FB, the end plate EP, and the top plate TP of the module frame MF.

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

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

[0076] 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 the assembly line data ALD, the assembly line AL of the first part P1 and the second part P2, and portions of the first part P1 and the second part P2 adjacent to the assembly line AL may be scanned with the inspection beam IB. The area on the module frame MF scanned with the inspection beam IB may include a zigzag line (e.g., a triangular waveform line). The sampling frequency of the scanning of 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 a boundary line between the first part P1 and the second part P2 of the module frame MF. The assembly line AL may be a profile of a contact surface between the first part P1 and the second part P2 of the module frame MF.

[0078] The Z-field measurement area (i.e., depth measurement limit) of the inspection beam IB may be in the range of several mm to tens of mm. The Z-field measurement area (i.e., depth measurement limit) of the inspection beam IB may be in the range of about 3 mm to about 12 mm. The resolution in the Z-axis direction of the inspection beam IB may be in the range of about 1 μm to about 100 μm.

[0079] The diameter of the XY field measurement area (i.e., horizontal scanning range) of the inspection beam IB may be in the range of several mm to several tens of mm. The diameter of the XY field measurement area (i.e., horizontal scanning range) of the inspection beam IB may be in the range of several mm to several tens of mm. The XY plane resolution of the inspection beam IB may be in the range of about 1 μm to about 100 μm. Here, the XY plane may be the scanning plane of the inspection beam IB, and the Z axis may be substantially perpendicular to the XY plane.

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

[0081] Due to manufacturing errors such as surface roughness, missing parts, and cracks of the first part P1 and the second part P2, and systematic and random errors due to the fixing device 200, there may be a gap GP between the first part P1 and the second part P2. When the reflected beam RB is not sensed or the depth of a part of the module frame MF is greater than the critical depth, the part of the corresponding module frame MF may be determined as the gap GP. When the module frame MF has a nonzero gap GP, the assembly line AL may be determined as the center line of the gap GP (e.g., the widthwise center line of the gap GP). The processor 140 may be configured to determine the assembly line AL from the gap GP. Unlike what is illustrated in FIG. 4, the first part P1 and the second part P2 may be ideally assembled, and the width of the gap GP may also be zero.

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

[0083] 1, 3 and 5, when the gap (GP, see FIG. 4) does not exceed the critical value (i.e., when the gap GP is equal to or smaller than the critical value), the coordinates of the weld line WL may be calibrated based on the assembly line data ALD in P130. The weld line WL may be determined based on a standard model of the module frame MF of the battery module BM loaded on the fixing device 200. The weld line WL may be a portion of an ideal module frame MF that is not subject to production and process errors and is to be welded. Due to production and process errors of the module frame MF, there may be a deviation between the weld line WL and the assembly line AL. The deviation between the weld line WL and the assembly line AL may include inclination, separation, and the like. 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. Calibrating the weld line WL may include calibrating the coordinates of the weld line WL based on a start point and an end point of the assembly line AL.

[0084] Subsequently, 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 along the calibrated weld line with the welding beam WB. According to an exemplary embodiment, welding the module frame MF based on the calibrated weld line may prevent unwelded and weak welds of the module frame, thereby improving the reliability of manufacturing the secondary battery.

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

[0086] In FIG. 6, the processes of P110 and P120 are substantially the same as those described with reference to FIGS. 3 to 5, and therefore a duplicated description thereof will be omitted.

[0087] 1 and 6, in P131, the module frame MF may be welded based on the assembly line data ALD. In this example, the welding line WL may not be calibrated based on the assembly line data ALD, but the module frame MF may be directly scanned with the welding beam WB based on the assembly line data ALD. The controller 150 is configured to perform many calculations in addition to calibrating the welding line WL. The controller 150 may reduce the computing power of the controller 150 by generating a signal for welding using the assembly line data ALD as it is, thereby improving the continuity and reliability of the process.

[0088] The present invention has been described in more detail above with reference to the drawings and embodiments, etc. However, the configurations described in the drawings or embodiments, etc. in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, so it should be understood that there may be various equivalents and modifications that can replace them at the time of filing this application. [Explanation of symbols]

[0089] 100 Secondary battery manufacturing equipment 110 First Beam Source 120 Scanner Head 121 Dichroic Mirror 123 First Scanning Mirror 124 2nd Scanning Mirror 125 Lens 127 Lens 130 OCT optical system 131 Second Beam Source 133 Beam splitter 135 Reference Mirror 137 Detector 138 First Scanning Mirror 139 2nd Scanning Mirror 140 processors 150 Controller 160 Servo Motor 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 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 for the module frame based on inspection signals generated by the detector; and a controller configured to control the servo motor based on assembly line data of the module frame.

2. The secondary battery manufacturing apparatus according to claim 1 , wherein the assembly line data includes coordinates of assembly lines of a first component and a second component of the module frame.

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

4. the controller is configured to calibrate a weld line based on the assembly line data; and 4. The secondary battery manufacturing apparatus according to claim 1, wherein the welding line is a portion of the module frame that is to be scanned by the welding beam.

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

6. The secondary battery manufacturing apparatus according to any one of claims 1 to 3, wherein the scanner head includes a dichroic mirror configured to transmit the welding beam and reflect the inspection beam.

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

8. 4. The secondary battery manufacturing apparatus according to claim 1, wherein the scanner head is configured to direct the inspection beam and the welding beam in an oblique direction relative to the module frame.

9. scanning the module frame with an inspection beam to collect assembly line data including assembly line coordinates of a first part and a second part of the module frame; and welding the first part and the second part based on the assembly line data.

10. The method for manufacturing a secondary battery according to claim 9 , wherein the assembly line data is collected based on a three-dimensional shape of the module frame.

11. a gap between the first part and the second part; The method for manufacturing a secondary battery according to claim 10 , wherein the assembly line is a center line of the gap.

12. 12. The method of manufacturing a secondary battery according to claim 9, wherein the step of welding the first part and the second part includes scanning the module frame with a welding beam based on the assembly line data.

13. The method for manufacturing a secondary battery according to claim 12 , wherein an optical axis of the welding beam and an optical axis of the inspection beam partially overlap each other.

14. the step of welding the first and second parts includes collecting assembly line data indicative of a position of the assembly line; and transmitting the assembly line data to a controller; The method for manufacturing a secondary battery according to any one of claims 9 to 11, wherein the controller is configured to control the movement of a scanner head configured to direct the inspection beam and the welding beam.

15. The method of manufacturing a secondary battery according to claim 14 , further comprising the step of calibrating coordinates of a weld line based on the assembly line data to generate a calibrated weld line.

16. 16. The method of manufacturing a secondary battery according to claim 15, wherein the step of welding the first part and the second part comprises scanning the module frame along the calibrated weld line with the welding beam.

Images