Apparatus and method for inspecting electrode assembly

Abstract

Disclosed are an apparatus and a method for inspecting an electrode assembly, which can perform inspection of the electrode assembly in a short period of time without destroying the electrode assembly. The apparatus may inspect an electrode assembly including a negative electrode, a positive electrode, and a separator interposed between the negative electrode and the positive electrode, and may include: a laser irradiation unit irradiating the electrode assembly with a laser beam; an illumination unit that irradiates the electrode assembly with light; an image acquisition unit that acquires an image of the electrode assembly irradiated with the laser beam or light; and a processor inspecting the electrode assembly based on the obtained image.

Description

Technical Field

[0001] The presented embodiments relate to an apparatus and method for inspecting an electrode assembly to check the quality of the electrode assembly. Background Art

[0002] Unlike primary batteries, which cannot be recharged, secondary batteries can be charged and discharged. Low-capacity secondary batteries are used in small portable electronic devices such as smartphones, feature phones, notebook computers, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources for motors in hybrid and electric vehicles and as power storage units. Such secondary batteries may include an electrode assembly containing a positive electrode and a negative electrode, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] With recent advances in science and technology, secondary batteries are being used in a wide variety of devices, and as a result, interest in the safety of secondary batteries is increasing.

[0004] This section is intended only to provide a better understanding of the technical background and therefore may include information that is not necessarily prior art. Summary of the Invention

[0005] At least one aspect of the present technology is to provide an inspection apparatus and / or an inspection method capable of inspecting a secondary battery and / or an electrode assembly in the secondary battery through visual inspection.

[0006] At least another aspect of the present technology is to provide an inspection apparatus and / or an inspection method capable of simultaneously performing various inspections to inspect the quality of a secondary battery and / or an electrode assembly in the secondary battery.

[0007] The above and other aspects and features of the present technology will become apparent from the following description of embodiments of the present technology.

[0008] According to some aspects of the present technology, an apparatus for inspecting an electrode assembly including a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode includes: a laser irradiation unit configured to irradiate the electrode assembly with a laser beam; an illumination unit configured to irradiate the electrode assembly with light; an image acquisition unit configured to obtain an image of the electrode assembly irradiated by the laser beam and / or light; and a processor configured to inspect the electrode assembly based on the obtained image.

[0009] According to other aspects of the present technology, a method for inspecting an electrode assembly includes performing, by an inspection device, an inspection of the electrode assembly for at least one of staggering, alignment, major diameter, volume, and folding state of the electrode assembly.

[0010] According to some embodiments, an inspection apparatus and / or an inspection method capable of performing an inspection of a secondary battery without destroying the secondary battery may be provided.

[0011] According to some embodiments, an inspection apparatus and / or an inspection method capable of performing fully automatic inspection of a secondary battery may be provided.

[0012] According to some embodiments, multiple inspections may be performed on a secondary battery within a short period of time.

[0013] However, aspects and features of the technology described herein are not limited to the above-described aspects and features, and other aspects and features not mentioned will be clearly understood by those skilled in the art from the detailed description given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The following drawings attached to this specification illustrate embodiments of the present technology and, together with the detailed description, further describe aspects and features of the present technology. Therefore, the present technology should not be interpreted as being limited to the drawings: Figure 1 is a perspective view of a cylindrical battery according to some embodiments; Figure 2 is a cross-sectional view of a cylindrical battery according to some embodiments; Figure 3 is a schematic diagram of an apparatus for inspecting an electrode assembly according to some embodiments; Figure 4 is a flow chart illustrating a method for inspecting an electrode assembly according to some embodiments; Figure 5 is a flow chart illustrating miswinding checking according to some embodiments; Figures 6A to 6B is a diagram illustrating miswinding checking according to some embodiments; Figure 7 is a flow chart illustrating miswinding checking according to some embodiments; Figure 8 is a diagram illustrating miswinding checking according to some embodiments; Figure 9 is a flow chart illustrating alignment checking according to some embodiments; Figure 10 is a diagram illustrating alignment checking according to some embodiments; Figure 11 is a flow chart illustrating alignment checking according to some embodiments; Figure 12 is a diagram illustrating alignment checking according to some embodiments; and Figure 13 is a flow chart illustrating long path checking according to some embodiments. DETAILED DESCRIPTION

[0015] Hereinafter, exemplary embodiments of the present technology will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be interpreted as limited to the ordinary meaning or dictionary meaning, and should be interpreted as having meanings and concepts consistent with the technical concept of the present technology based on the principle that the inventor(s) can act as his / her own lexicon compiler to appropriately define the concept of the term and thus interpret the technology in the most appropriate manner. The embodiments described in this specification and the configurations (constructions) shown in the drawings are only some of the embodiments of the present technology and do not represent all of the technical concepts, aspects, and features of the present technology. Therefore, it should be understood that there may be various equivalents and modifications that can replace or modify the embodiments described herein when filing this application.

[0016] It will also be understood that the terms "comprises," "includes," and / or variations thereof, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Furthermore, the use of "may" when describing embodiments of the present technology refers to "one or more embodiments of the present technology."

[0017] In the drawings, the sizes of various elements, layers, etc. may be exaggerated for clarity of illustration. Like reference numerals denote like elements.

[0018] Referring to two compared elements, features, etc. as "the same" may mean that they are "substantially the same." Thus, the phrase "substantially the same" may include situations where there is a low degree of variation (e.g., 5% or less) that is considered in the art. Furthermore, referring to a parameter as being uniform in a given area may mean that it is uniform in terms of average value.

[0019] It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the exemplary embodiments, the first element, first component, first region, first layer or first part discussed below may be referred to as the second element, second component, second region, second layer or second part.

[0020] Throughout the specification, unless otherwise specified, each element may be in the singular or in the plural.

[0021] When any element is referred to as being disposed “on” (or “under”) or “on” (or “under”) a component, it may mean that the element is placed in contact with the upper (or lower) surface of the component, and may also mean that another component may be interposed between the component and any element disposed (or located or arranged) on (or under) the component.

[0022] Furthermore, it will be understood that when an element is referred to as being “coupled,” “linked,” or “connected” to another element, the elements may be directly “coupled,” “linked,” or “connected” to each other, or an intervening element may be present therebetween through which the element may be “coupled,” “linked,” or “connected” to the other element. Furthermore, when a part is referred to as being “electrically coupled” to another part, the part may be directly connected to the other part, or an intervening part may be present therebetween such that the part and the other part are indirectly connected to each other.

[0023] Throughout this specification, unless otherwise specified, when "A and / or B" is stated, it means A, B, or A and B. That is, "and / or" includes any and all combinations of the listed items. When "C to D" is stated, unless otherwise specified, it means C or greater and D or less.

[0024] The terminology used herein is for the purpose of describing embodiments of the present technology and is not intended to be limiting of the technology.

[0025] Typically, to check whether secondary batteries have been safely manufactured, a quality inspection is performed on a plurality of secondary batteries. The quality inspection of secondary batteries may include a miswinding inspection, an alignment inspection, a major diameter inspection, a volume inspection, and / or an end folding state inspection.

[0026] Since there is no instrument capable of automatically inspecting secondary batteries, operators manually inspect secondary batteries. For example, this is done by destroying the secondary battery. However, the inventors have recognized that such inspections result in significant battery waste, high time consumption, and inconvenience.

[0027] On the other hand, X-ray or CT equipment has been used to inspect the quality of secondary batteries to prevent damage. However, these instruments are time-consuming and have low reliability. In addition, due to the use of radiation, this method has difficulty ensuring a safe working environment and / or requires excessive inspection costs.

[0028] Figure 1 is a perspective view of a cylindrical battery according to some embodiments.

[0029] Figure 2 is a cross-sectional view of a cylindrical battery according to some embodiments.

[0030] Reference Figure 1 and Figure 2 According to various embodiments, a cylindrical lithium-ion secondary battery (or "secondary battery") 100 may include a cylindrical can 110, an electrode assembly 120, and a cap assembly 140. The cylindrical lithium-ion secondary battery 100 may also include a center pin 130. In addition, in the secondary battery 100 according to some embodiments, the cap assembly 140 also performs current interruption and is therefore generally referred to as a current interruption device.

[0031] The cylindrical can 110 may include a substantially circular bottom 111 and a cylindrical sidewall 112 extending upward from the circumference of the bottom 111 to a certain length. During the manufacturing process of the secondary battery, the upper portion of the cylindrical can 110 is open. Therefore, during the assembly process of the secondary battery, the electrode assembly 120 and the center pin 130 can be inserted into the cylindrical can 110 together with the electrolyte. The cylindrical can 110 may be formed of, for example, steel, stainless steel, aluminum, an aluminum alloy, or an equivalent thereof, but is not limited thereto.

[0032] Furthermore, relative to the cap assembly 140 , the cylindrical can 110 may include a curling portion 113 inwardly recessed at a lower portion of the cap assembly 140 and a crimping portion 114 inwardly bent at an upper portion of the cap assembly 140 to prevent the cap assembly 140 from being separated outwardly.

[0033] The electrode assembly 120 can be housed within the cylindrical can 110. The electrode assembly 120 may include a negative electrode plate 121, a positive electrode plate 122, and a separator 123. The negative electrode plate 121 has a negative active material (e.g., graphite, carbon, etc.) coated on a negative current collector, and the positive electrode plate 122 has a positive active material (e.g., transition metal oxides (LiCoO2, LiNiO2, LiMn2O4, etc.)) coated on a positive current collector. The separator 123 is interposed between the negative and positive electrode plates 121 and 122 to prevent short circuits while allowing only lithium ion migration. Furthermore, the negative and positive electrode plates 121, 122, and separator 123 may be wound into a substantially cylindrical shape. As an example, the negative current collector may be formed of copper (Cu) foil, the positive current collector may be formed of aluminum (Al) foil, and the separator may be formed of polyethylene (PE) or polypropylene (PP), without limitation.

[0034] Furthermore, the negative electrode tab 124 may be welded to the negative electrode plate 121 to protrude downward by a certain length, and the positive electrode tab 125 may be welded to the positive electrode plate 122 to protrude upward by a certain length, and vice versa. As an example, the negative electrode tab 124 may be formed of copper (Cu) or nickel (Ni), and the positive electrode tab 125 may be formed of aluminum (Al), but is not limited thereto.

[0035] In addition, the negative electrode tab 124 of the electrode assembly 120 can be welded to the bottom 111 of the cylindrical can 110. Therefore, the cylindrical can 110 can be used as a negative electrode. It should be understood that the positive electrode tab 125 can be welded to the bottom 111 of the cylindrical can 110 to serve as a positive electrode.

[0036] In addition, a first insulating plate 126 may be placed between the electrode assembly 120 and the bottom 111. The first insulating plate 126 is coupled to the cylindrical can 110 and has a first hole 126a formed at its center and a second hole 126b formed at its periphery. The first insulating plate 126 may be used to prevent the electrode assembly 120 from electrically contacting the bottom 111 of the cylindrical can 110. Specifically, the first insulating plate 126 may be used to prevent the positive electrode plate 122 of the electrode assembly 120 from electrically contacting the bottom 111. Here, the first hole 126a is used to allow the gas to quickly flow upward through the center pin 130 when a large amount of gas is generated due to an abnormality in the secondary battery, and the second hole 126b is used to allow the negative electrode tab 124 to be welded therethrough to the bottom 111.

[0037] Furthermore, a second insulating plate 127 may be interposed between the electrode assembly 120 and the cap assembly 140. The second insulating plate 127 is coupled to the cylindrical can 110 and has a first hole 127a formed at its center and a plurality of second holes 127b formed around its periphery. The second insulating plate 127 may be used to prevent the electrode assembly 120 from electrically contacting the cap assembly 140. Specifically, the second insulating plate 127 may be used to prevent the negative electrode plate 121 of the electrode assembly 120 from electrically contacting the cap assembly 140. Here, the first hole 127a may be used to allow a large amount of gas to flow quickly into the cap assembly 140 in the event of an abnormality in the secondary battery, and one of the second holes 127b may be used to allow the positive electrode tab 125 to be welded therethrough to the cap assembly 140. Furthermore, the remaining second holes 127b may be used to allow the electrolyte to flow quickly into the cylindrical can 110 during the electrolyte injection process.

[0038] In addition, the first hole 126a of the first insulating plate 126 and the first hole 127a of the second insulating plate 127 may have a diameter smaller than that of the center pin 130 to prevent the center pin 130 from electrically contacting the bottom 111 of the cylindrical can 110 or the cap assembly 140 due to external impact.

[0039] The center pin 130 can be formed in the form of a hollow circular tube and can be substantially coupled to the center of the electrode assembly 120. Such a center pin 130 can be formed of, for example, steel, stainless steel, aluminum, an aluminum alloy, or polybutylene terephthalate, but is not limited thereto. The center pin 130 can be used to suppress deformation of the electrode assembly 120 during charging and discharging of the battery and can serve as a flow conduit for gases generated within the secondary battery. Of course, in some embodiments, the center pin 130 can be omitted.

[0040] The cap assembly 140 may include a top plate 141 , a middle plate 142 , an insulating plate 143 , and a bottom plate 144 .

[0041] The middle plate 142 may be disposed under the top plate 141 and may have a substantially flat shape.

[0042] The insulating plate 143 may be formed in a circular ring shape having a constant width in a bottom view. Furthermore, the insulating plate 143 may serve to insulate the middle plate 142 and the bottom plate 144 from each other. The insulating plate 143 may be placed between the middle plate 142 and the bottom plate 144, for example, and may be ultrasonically welded to the middle plate 142 and the bottom plate 144, without limitation.

[0043] The cap assembly 140 may be fixed to the interior of the cylindrical can 110 via a gasket 145 to seal the housing. The gasket 145 may electrically insulate between the cylindrical can 110 and the cap assembly. The gasket 145 may prevent moisture or electrolyte from flowing in or out between the cylindrical can and the cap assembly.

[0044] However, it should be understood that the present technology is not limited to this, and the shell can have various shapes (such as a circular shape, a bag shape, etc.), and can be formed of metal (such as aluminum, aluminum alloy and nickel-plated steel), a laminated film or plastic that constitutes a bag, without limitation.

[0045] Already referenced Figure 1 and Figure 2 A cylindrical lithium-ion secondary battery 100 according to some embodiments is described. On the other hand, as described herein, safety concerns regarding the secondary battery 100 have been increasing in recent years. Therefore, when the manufacture of the secondary battery 100 is completed, the secondary battery 100 is quality-checked before being applied to a product. Here, the quality inspection of the secondary battery 100 may be a process of inspecting the appearance of the secondary battery 100 to ensure that the secondary battery 100 has been properly manufactured according to the design. The quality inspection of the secondary battery 100 may be performed by visually inspecting the electrode assembly 120 in the secondary battery.

[0046] Next, a method and / or apparatus for inspecting an electrode assembly in the secondary battery 100 will be described.

[0047] On the other hand, the objects to be inspected by the apparatus for inspecting electrode assemblies according to some embodiments are not limited to electrode assemblies. The inspection apparatus can inspect not only electrode assemblies but also secondary batteries in which electrode assemblies are embedded, battery modules including secondary batteries, battery packs, and the like. Furthermore, the inspection apparatus can inspect any object formed by stacking multiple layers, such as an electrode assembly. To simplify the description, an electrode assembly will be described herein as a non-limiting example of an object to be inspected.

[0048] Figure 3 is a schematic diagram of an apparatus for inspecting an electrode assembly according to some embodiments.

[0049] exist Figure 3 In the embodiment, the electrode assembly 200 is shown as including, for example Figure 1 and Figure 2 The electrode assembly 120 shown in FIG. Figure 1 and Figure 2 As described, the electrode assembly 200 may include a negative electrode, a positive electrode, and a separator placed between the negative electrode and the positive electrode. The electrode assembly 200 may include a laminated structure formed by stacking the negative electrode, the positive electrode, and the separator. The electrode assembly 200 includes, for example, a core-type electrode assembly formed by winding such a laminated structure in one direction. The electrode assembly 200 to be inspected by the inspection equipment according to some embodiments is not limited to the core-type, and may include, for example, a bag-type, a prismatic type, a coil type, and the like. However, in order to simplify the description, the core-type electrode assembly 200 will be described as the object of inspection by way of example below.

[0050] exist Figure 3 In the figure, the inspection device 300 represents a device for inspecting the electrode assembly 200. The inspection device 300 inspects the quality of the electrode assembly 200. Specifically, the inspection device 300 inspects the quality of the electrode assembly 200 by inspecting the shape of the electrode assembly 200 (i.e., the appearance of the electrode assembly 200). For example, the inspection device 300 inspects the electrode assembly 200 for at least one of winding, alignment, major diameter, volume, and folded state.

[0051] to this end, Figure 3 The inspection device 300 shown in FIG includes a laser irradiation unit 310, an illumination unit 330, an image acquisition unit 340, and a processor 360. The inspection device 300 may further include a reflector 320 and a lens unit 350. However, the components of the inspection device 300 are not limited to Figure 3 The inspection device 300 may include components such as Figure 3 The components shown may be fewer than the components shown and / or may include components other than Figure 3The inspection device 300 may include more components than those shown in the figure. For example, the inspection device 300 may further include a memory (not shown) (e.g., a non-transitory computer-readable medium) that stores instructions and / or data required for the operation of the inspection device 300, and a communication unit (not shown) that enables the inspection device 300 to communicate with external devices and / or external servers. The processor may be configured to execute the instructions stored in the memory.

[0052] The laser irradiation unit 310 may emit a laser beam toward the electrode assembly 200. To this end, the laser irradiation unit 310 may be spaced apart from the electrode assembly 200 so that the electrode assembly 200 may be irradiated with the laser beam.

[0053] The laser irradiation unit 310 emits a laser beam toward the electrode assembly 200. The laser irradiation unit 310 includes at least one of a gas laser, a solid-state laser, and an excimer laser. Gas lasers include, for example, He-Ne lasers, Ar lasers, and / or CO2 lasers. Solid-state lasers include, for example, any laser optically pumped by a flash lamp and / or an arc lamp. Excimer lasers include any laser that emits light in the ultraviolet band at high power. However, it should be understood that the present technology is not limited thereto, and the laser irradiation unit 310 may include any device capable of emitting a laser beam amplified by inductive emission.

[0054] Alternatively, the laser irradiation unit 310 may emit a laser beam toward the electrode assembly 200 through the reflector 320. In some embodiments, as Figure 3 As shown in FIG, the reflector 320 may be implemented by one or more reflectors that reflect the emitted laser beam received from the laser irradiation unit 310 toward the electrode assembly 200. Specifically, the laser irradiation unit 310 emits a laser beam toward the reflector 320. The reflector 320 reflects the laser beam toward the electrode assembly 200. The reflector 320 may be spaced apart from the laser irradiation unit 310 to receive the laser beam emitted from the laser irradiation unit 310. However, the reflector 320 may also be disposed within the laser irradiation unit 310 to directly contact the laser beam emitted from the laser irradiation unit 310. In addition, the reflector 320 (as shown in the figure) is spaced apart from the electrode assembly 200 so that the received laser beam can be reflected toward the electrode assembly 200. With this structure, the reflector 320 (e.g., a mirror) can ensure that the laser beam can be accurately transmitted to the electrode assembly 200.

[0055] The laser beam transmitted to the electrode assembly 200 may be reflected from the electrode assembly 200 to be acquired by the image acquisition unit 340. Therefore, the inspection apparatus 300 according to some embodiments may inspect the electrode assembly 200 based on the laser phase difference.

[0056] The lighting unit 330 can emit light toward the electrode assembly 200. The lighting unit 330 can be spaced apart from the electrode assembly 200 to emit light. For example, the lighting unit 330 is arranged so that the light emitted from the lighting unit 330 is directed toward the upper surface of the electrode assembly 200. The lighting unit can illuminate the electrode assembly with light. The lighting unit 330 can be provided in multiple numbers, for example, to emit light toward the upper side, lower side, left side, and / or right side of the upper surface of the electrode assembly 200. Alternatively, the (multiple) lighting unit 330 can be a single light source surrounding the upper side, lower side, left side, and / or right side of the upper surface of the electrode assembly 200. Alternatively, the lighting unit 330 can be implemented by the laser irradiation unit 310 or the laser irradiation unit 310 can be implemented by the lighting unit 330. In this case, one of the laser irradiation unit 310 and the lighting unit 330 can be omitted.

[0057] The light transmitted to the electrode assembly 200 may be reflected from the electrode assembly 200 to be acquired by the image acquisition unit 340 .

[0058] The image acquisition unit 340 can obtain an image of the electrode assembly 200 irradiated with a laser beam or light. For example, the image acquisition unit 340 can obtain an image of the electrode assembly 200 irradiated with a laser beam and / or light refracted by the lens unit 350. To this end, the lens unit 350 can be spaced apart from the image acquisition unit 340 and / or the electrode assembly 200. For example, the lens unit 350 can be configured so that the laser beam and / or light reflected from the electrode assembly 200 is bent at 90 degrees to reach the image acquisition unit 340. The lens unit can allow the image acquisition unit to obtain an image of the electrode assembly.

[0059] In some embodiments, the image acquisition unit 340 includes a sensor capable of acquiring an image, such as a visual sensor (including, for example, a visual camera), a LiDAR sensor, and / or a laser sensor.

[0060] The image obtained by the image acquisition unit 340 may include any image representing information about the electrode assembly 200 , such as a photographic image, an image representing a distance or a property, and the like.

[0061] The image obtained by the image acquisition unit 340 includes, for example, an image of the upper surface of the electrode assembly 200. Here, the image of the upper surface of the electrode assembly 200 includes an image of a laser beam incident on the upper surface of the electrode assembly 200. Alternatively, the image of the upper surface of the electrode assembly 200 may include a photographic image of the upper surface of the electrode assembly 200.

[0062] The upper surface of the electrode assembly 200 is a cross-section in a direction in which the stacked shape of the negative electrode, the positive electrode, and the separator in the electrode assembly 200 can be observed. For example, the upper surface of the electrode assembly 200 is a cross-section perpendicular to the winding axis of the electrode core, and when the winding core of the electrode core is observed in the direction of the winding axis of the electrode core, the upper surface of the electrode assembly 200 can be observed.

[0063] The processor 360 may control all or some components of the inspection device 300. The processor 360 may be embedded in the inspection device 300. Alternatively, the processor 360 may be placed outside the inspection device 300 and may control each of the components in the inspection device 300 through wired communication or wireless communication.

[0064] The processor 360 includes, for example, at least one of a central processing unit (CPU), a microprocessor unit (MPU), a microcontroller unit (MCU), a graphics processing unit (GPU), a digital signal processor (DSP), a floating point unit (FPU), an application specific integrated circuit (ASIC), and a field programmable gate array (FPGA).

[0065] The processor 360 may inspect the electrode assembly 200 based on the obtained image.

[0066] In this way, the inspection device 300 according to some embodiments can acquire an image of the electrode assembly 200 and inspect the quality of the electrode assembly 200 without damaging the electrode assembly 200. In addition, the inspection device 300 can simultaneously perform two or more inspections on the electrode assembly 200. In addition, the inspection device 300 allows the inspection of the electrode assembly 200 to be performed automatically. Therefore, the inspection device 300 improves the operator load rate while minimizing the number of electrode assemblies 200 that will be damaged and then discarded due to inspection.

[0067] Figure 4 is a flow chart illustrating a method for inspecting an electrode assembly according to some embodiments. As a non-limiting example, Figure 4 Shown for the Figure 3 A method of inspecting the electrode assembly 200 using the inspection apparatus 300 shown in FIG.

[0068] The method for inspecting an electrode assembly according to some embodiments includes the step of irradiating the electrode assembly 200 with a laser beam and / or light (step S101). Figure 3 , the laser irradiation unit 310 may emit a laser beam toward the electrode assembly 200, and the lighting unit 330 may emit light toward the electrode assembly 200. Here, the laser irradiation unit 310 may emit laser light at the same time as the lighting unit 330 emits light, may emit laser light before the lighting unit 330 emits light, or may emit laser light after the lighting unit 330 emits light.

[0069] The method for inspecting an electrode assembly according to some embodiments includes a step of obtaining an image of the electrode assembly 200 irradiated with a laser beam and / or light (step S102). Figure 3 , the image acquisition unit 340 can obtain an image of the electrode assembly 200.

[0070] The method for inspecting an electrode assembly according to some embodiments includes a step of inspecting the electrode assembly 200 based on the obtained image (step S103). Figure 3 As shown in , the processor 360 can inspect the quality of the electrode assembly 200 based on the obtained image. For example, based on the obtained image, the processor 360 inspects the electrode assembly 200 for at least one of its winding, alignment, major diameter, volume, and one-end folding state.

[0071] The following description will focus on one or more inspections performed by the inspection device 300 .

[0072] Figure 5 is a flow chart illustrating miswinding checking according to some embodiments.

[0073] Figure 6A and Figure 6B is a diagram illustrating miswinding checking according to some embodiments.

[0074] Figure 5 、 Figure 6A and Figure 6B The electrode assembly 200 is shown as a wrong winding inspection Figure 3 and Figure 4 An example of inspecting the quality of the electrode assembly 200 is shown in FIG.

[0075] Reference Figure 5 The inspection apparatus 300 according to some embodiments calculates a phase difference between two of the negative electrode, the positive electrode, and the separator based on the obtained image (step S201 ).

[0076] For example, Figure 6A As shown in FIG, the laser beam b emitted from the laser irradiation unit 310 is directed toward the electrode assembly 200. Figure 3 and Figure 4 As shown in FIG, the laser beam b may be reflected toward the electrode assembly 200 by the reflector 320 .

[0077] Figure 6B An image of the upper surface 200t of the electrode assembly is shown. The image acquisition unit 340 may acquire an image of the upper surface 200t of the electrode assembly caused by the laser beam b.

[0078] Based on the obtained image, the processor 360 calculates a phase difference between at least two of the negative electrode, the positive electrode, and the separator. The phase difference may be caused by, for example, the thickness of at least one of the negative electrode, the positive electrode, and the separator.

[0079] Specifically, processor 360 determines regions where laser beam b has different phases. For example, processor 360 determines that laser beam image b1 created in the first region and laser beam image b2 created in the second region have different phases. For example, processor 360 determines that the first region is 5 mm inward of the second region based on the phase of laser beam image b1 created in the first region and the phase of laser beam image b2 created in the second region. In this way, processor 360 calculates the phase difference between the materials based on the image of laser beam b formed for electrode assembly 200.

[0080] Reference Figure 5 , the inspection apparatus 300 according to some embodiments performs a wrong winding inspection of the electrode assembly 200 based on the calculated phase difference (step S202 ).

[0081] Here, the winding inspection is performed to inspect the winding state between the materials of the electrode assembly 200. The materials of the electrode assembly 200 include at least one of a negative electrode, a positive electrode, and a separator. Specifically, the winding inspection may include measuring the height difference between the materials.

[0082] The processor 360 performs a wrong winding check of the electrode assembly 200 based on the calculated phase difference. Figure 7 and Figure 8 The miswinding check performed by the processor 360 based on the calculated phase difference is described in more detail.

[0083] As such, the inspection apparatus 300 according to some embodiments can quickly inspect the electrode assembly 200 for winding errors in real time using a laser beam without damaging the electrode assembly 200 .

[0084] Figure 7 is a flow chart of a miswinding check according to some embodiments.

[0085] Figure 8 is a diagram illustrating miswinding checking according to some embodiments.

[0086] Now refer to Figure 7 and Figure 8 , will be described in more detail Figures 3 to 6B At least one example of a miswinding inspection of the electrode assembly 200 is shown in FIG. Figure 8 , the electrode assembly 200 is formed by stacking a negative electrode 210 , a positive electrode 220 , and a separator 230 such that the separator 230 is interposed between the negative electrode 210 and the positive electrode 220 .

[0087] Reference Figure 7 According to some embodiments, the inspection apparatus 300 calculates thickness based on the phase difference (step S301 ).

[0088] The processor 360 calculates the thickness of at least one of the negative electrode 210, the positive electrode 220, and the separator 230 based on the phase difference. For example, in a structure in which the negative electrode 210 is placed between two separators 230, the two separators 230 may have a different phase than the negative electrode 210 placed therebetween. Alternatively, for example, in a structure in which the positive electrode 220 is placed between two separators 230, the two separators 230 may have a different phase than the positive electrode 220 placed therebetween. Therefore, the phase difference is, for example, the phase difference between the negative electrode 210 and the separator 230 or between the positive electrode 220 and the separator 230. Based on such a phase difference between at least two materials, the processor 360 can calculate the thickness of each material. In other words, the processor 360 can calculate the thickness of at least one of the negative electrode 210, the positive electrode 220, and the separator 230.

[0089] Reference Figure 7 According to some embodiments, the inspection device 300 calculates the miswinding distance based on the thickness (step S302 ).

[0090] Based on the calculated thickness, the processor 360 can calculate the stagger distance between at least two of the negative electrode 210, the positive electrode 220, and the separator 230. Here, the stagger distance corresponds to the height difference between the two materials. Here, the direction representing the height difference between the two materials is perpendicular to the direction representing the thickness of one material.

[0091] The staggered winding distance represents, for example, a height difference h1 between the negative electrode 210 and the positive electrode 220 , a height difference h2 between the separator 230 and the negative electrode 210 , and / or a height difference between the separator 230 and the positive electrode 220 .

[0092] The processor 360 calculates the stagger distance based on the thickness. For example, the processor 360 may use trigonometry (trigonometric functions) to calculate the stagger distance based on the calculated thickness. For example, the processor 360 may calculate the stagger distance according to Equation 1: (Equation 1)

[0093] Here, h represents the staggered distance between at least two of the negative electrode 210, the positive electrode 220, and the separator 230; d represents the thickness of at least one of the negative electrode 210, the positive electrode 220, and the separator 230; and θ represents the angle between the shortest distance straight line connecting the corner of one material to the corner of another material adjacent thereto and the longitudinal direction of the one material. Here, the corner of the one material is positioned close to the adjacent material in the direction of the upper surface of the electrode assembly 200. In addition, the corner of the adjacent material is positioned away from the one material in the direction of the upper surface of the electrode assembly 200. The shortest distance straight line is the shortest line among the straight lines connecting the corner of the one material to the corner of the adjacent material.

[0094] For example, refer to Figure 8 , separator 230 is placed adjacent to negative electrode 210. A corner of separator 230 is, for example, corner e1. A corner of negative electrode 210 is, for example, corner e2. The shortest straight line is the line connecting corner e1 to corner e2. d is the thickness of the adjacent material, i.e., the thickness of negative electrode 210. θ is the angle between the line connecting corner e1 to corner e2 and the longitudinal direction of separator 230. Using these values, processor 360 can calculate the miswinding value (height difference h2) between separator 230 and negative electrode 210.

[0095] Reference Figure 7 According to some embodiments, the inspection device 300 performs a miswinding inspection based on the miswinding distance (step S303 ).

[0096] The processor 360 may store the miswind distance in a memory (e.g., Figure 3 The calculated staggered winding distance is compared with a range of staggered winding distances (in a memory described in the embodiment). When the processor 360 determines that the calculated staggered winding distance falls within the range of staggered winding distances, the processor 360 determines that the winding of the electrode assembly 200 is properly performed. When the processor 360 determines that the calculated staggered winding distance does not fall within the range of staggered winding distances, the processor 360 determines that the winding of the electrode assembly 200 is not properly performed (i.e., the electrode assembly 200 is staggered).

[0097] Therefore, the inspection apparatus 300 according to some embodiments can quickly inspect the electrode assembly 200 for winding errors in real time using a laser beam without damaging the electrode assembly 200 .

[0098] Figure 9 is a flow chart of alignment checking according to some embodiments.

[0099] Figure 10 is a diagram illustrating alignment checking according to some embodiments.

[0100] Figure 9 and Figure 10The alignment check of the electrode assembly 200 is shown as Figures 3 and 4 An example of inspecting the quality of the electrode assembly 200 is shown in FIG.

[0101] Reference Figure 9 According to some embodiments, the inspection apparatus 300 detects one end of the negative electrode and / or one end of the positive electrode based on the obtained image (step S401 ).

[0102] As described above, the image obtained includes, for example, an image of the upper surface of the pole core in a wound state. The image obtained may also include an image of the side surface of the pole core in an unfolded state. Figure 10 As shown in FIG, the image of the side surface of the electrode core in the unfolded state includes, for example, an image in which the electrode core is unfolded to expose one end of the negative electrode 210 and / or one end of the positive electrode 220.

[0103] One end of the negative electrode 210 and / or one end of the positive electrode 220 includes a starting point (front end) of the negative electrode 210 and / or the positive electrode 220. Here, the starting point is the end of each layer located at the center of the electrode core when the electrode assembly 200 is wound. Optionally, one end of the negative electrode 210 and / or the positive electrode 220 includes a distal end (tip end) of the negative electrode 210 and / or the positive electrode 220. The distal end is the end of each layer located at the periphery of the electrode core when the electrode assembly 200 is wound. In other words, one end of the negative electrode 210 and / or the positive electrode 220 may include one end of each layer included in the electrode assembly 200. To simplify the description, Figure 9 and Figure 10 The “front end” is shown as an example of the “one end”.

[0104] Processor 360 can detect one end p1 of the negative electrode and one end p2 of the positive electrode based on the acquired image. For example, processor 360 uses a laser beam to inspect the area of each material and detects one end of each material based on an image of the top surface of the coiled electrode core. As another example, processor 360 detects one end of each material based on an image of the side surface of the unwound electrode core.

[0105] Here, one end p1 of the negative electrode represents at least one point between the uncoated portion 211 and the coated portion 212. The uncoated portion 211 is an uncoated portion of the negative electrode substrate. The coated portion 212 is a portion of the negative electrode substrate coated with, for example, a negative electrode active material.

[0106] The one end p2 of the positive electrode 220 may be an end portion of the positive electrode 220 on one side in the longitudinal direction of the positive electrode 220 .

[0107] For example, in the unfolded state of the electrode assembly 200 , one end p1 of the negative electrode and one end p2 of the positive electrode are located at the winding core of the electrode assembly 200 .

[0108] The processor 360 can calculate the distance between the negative electrode end p1 and the positive electrode end p2 from the negative electrode end p1 and the positive electrode end p2 detected in this manner. Figures 11 to 12 This process is described in more detail. However, it should be understood that this process is provided as an example, and the processor 360 can calculate the distance between the negative electrode 210 and the positive electrode 220, the distance between the negative electrode 210 and the separator 230, and the distance between the positive electrode 220 and the separator 230 in any of the ways described above.

[0109] Reference Figure 9 , the inspection apparatus 300 according to some embodiments performs an alignment inspection of the electrode assembly 200 based on one end of the negative electrode and / or one end of the positive electrode (step S402 ).

[0110] The alignment check may be a process of checking the winding starting point of each material in the process of winding the secondary battery. For example, in the alignment check, the winding starting point of each of the negative electrode 210, the positive electrode 220 and / or the separator 230 in the electrode assembly 200 is checked.

[0111] The processor 360 may check the winding starting point of each of the materials included in the electrode assembly 200 through one end p1 of the negative electrode, one end p2 of the positive electrode 220, and / or one end (not shown) of the separator 230. In addition, the processor 360 may check the alignment between at least two materials in the electrode assembly 200 through one end p1 of the negative electrode, one end p2 of the positive electrode 220, and / or one end (not shown) of the separator 230.

[0112] In this way, the inspection device 300 according to some embodiments can inspect the winding starting point of each material in the material, and can automatically calculate the alignment quality between them by detecting one end of the negative electrode 210, one end of the positive electrode 220 and / or one end of the separator 230, and then calculating the distance between them.

[0113] Figure 11 is a flow chart illustrating alignment checking according to some embodiments.

[0114] Figure 12 is a diagram illustrating alignment checking according to some embodiments.

[0115] Reference Figure 11 and Figure 12 , describing the execution in more detail Figure 3 、 Figure 4 、 Figure 9 and Figure 10 An example of alignment inspection of the electrode assembly 200 is shown in FIG. Figure 12 An upper surface of the electrode assembly 200 is shown.

[0116] Reference Figure 11 According to some embodiments, the inspection device 300 determines the center point of the pole core (step S501).

[0117] The processor 360 may determine the center point c of the electrode assembly 200 forming the electrode core. Here, the center point c is located at the winding core of the electrode assembly 200. For example, the center point c corresponds to the central axis around which the electrode assembly 200 is wound. The processor 360 may determine the center point c of the electrode core based on an image obtained showing the upper surface of the wound electrode assembly 200.

[0118] Reference Figure 11 , the inspection apparatus 300 according to some embodiments calculates the length of an arc corresponding to the distance between one end of the negative electrode and one end of the positive electrode based on the center point (step S502 ).

[0119] The processor 360 can calculate the length of the arc corresponding to the distance between the materials in the electrode assembly based on the center point c and one end of each material. For example, the processor 360 determines a first straight line l1 connecting one end p1 of the negative electrode to the center point c and a second straight line l2 connecting one end p2 of the positive electrode to the center point c. The processor 360 can calculate the angle between the first straight line l1 and the second straight line l2. Based on the angle a between the first straight line l1 and the second straight line l2, the processor 360 calculates the length of the arc between one end p1 of the negative electrode and one end p2 of the positive electrode. For example, the processor 360 calculates the length of the arc according to Equation 2: (Equation 2)

[0120] Here, s is the length of the arc corresponding to the distance between materials in the electrode assembly. For example, s is the length of the arc between one end p1 of the negative electrode and one end p2 of the positive electrode. Here, t is the length of the entire arc of the electrode core corresponding to the circumference of the electrode core. Furthermore, a is the angle between materials in the electrode assembly (e.g., in degrees). The angle (°) has a value between 0° and 360°.

[0121] In this manner, processor 360 can calculate the length of an arc corresponding to the distance between materials in the electrode assembly. For example, processor 360 can calculate the length of an arc between one end of the positive electrode and one end of the negative electrode.

[0122] Reference Figure 11 , the inspection device 300 according to some embodiments performs an alignment inspection based on the length of the arc (step S503 ).

[0123] The processor 360 may perform an alignment check of the electrode assembly 200 by comparing at least one of one end of each material and the length of an arc between the materials with data stored in a memory.

[0124] As such, the inspection apparatus 300 according to some embodiments can inspect the winding start point of each material and can automatically inspect alignment between materials by detecting one end of the negative electrode 210 , the positive electrode 220 , and / or the separator 230 and calculating the distance therebetween.

[0125] Figure 13 is a flow chart illustrating long path checking according to some embodiments.

[0126] Figure 13 The long diameter of the electrode assembly 200 is shown as Figure 3 and Figure 4 An example of inspecting the quality of the electrode assembly 200 is shown in FIG.

[0127] Reference Figure 13 According to some embodiments, the inspection apparatus 300 determines the major diameter of the electrode assembly 200 based on the obtained image (step S601 ).

[0128] As described above, the obtained image may include an image of the upper surface of the electrode assembly 200 .

[0129] Processor 360 may extract a pair of first points on the upper surface of electrode assembly 200 (e.g., from an image of the upper surface). Processor 360 may calculate a first length corresponding to the distance between the first points. Processor 360 may calculate a second length corresponding to the distance between a pair of second points (extracted by the processor from the image). Here, one point in the pair of first points may overlap with one point in the pair of second points. However, it should be noted that the pair of first points does not overlap with the pair of second points. In other words, each point in the pair of first points may be different from each point in the pair of second points. Processor 360 may calculate a second length corresponding to the distance between the pair of second points. Processor 360 may compare the first length with the second length and determine the longer of the first and second lengths as the major diameter of electrode assembly 200. For example, processor 360 may determine the major diameter as the longest length of electrode assembly 200 by repeating this process.

[0130] Reference Figure 13 According to some embodiments, the inspection apparatus 300 performs a long diameter inspection (test) of the electrode assembly 200 based on the determined long diameter (step S602 ).

[0131] The major diameter inspection is a process of connecting two points on the upper surface of the secondary battery 100 with a line to determine the major diameter, which is the maximum length at each angle.

[0132] The processor 360 may compare the determined major diameter with a range of major diameters stored in a memory to determine whether the electrode assembly 200 is properly manufactured.

[0133] Additionally or alternatively, the inspection device 300 according to some embodiments may perform a volume inspection. Volume inspection is the process of photographing the upper surface of a secondary battery with a camera and measuring the area of the secondary battery based on the photographed image. For example, the processor 360 measures and / or inspects the volume of the electrode assembly 200 based on the obtained image.

[0134] Additionally or alternatively, the inspection device 300 according to some embodiments can perform a one-end folding state inspection. The one-end folding state inspection is a process of checking the winding state of each material and checking whether there is an overlapping portion between the materials. For example, the processor 360 checks the folding state of at least one of the negative electrode, the positive electrode, and the separator based on the image of the upper surface of the display electrode assembly 200 obtained. However, the inspection device 300 can also perform a one-end folding state inspection of the electrode assembly 200 when each material is unfolded.

[0135] Thus, the inspection device 300 according to some embodiments can perform various quality inspections on the electrode assembly 200. In addition, the inspection device 300 can perform these inspections simultaneously or sequentially within a short period of time. In addition, the inspection device 300 can perform these inspections without damaging the electrode assembly 200.

[0136] Although the present technology has been described with reference to some embodiments and drawings showing aspects thereof, the present technology is not limited thereto, and those skilled in the art may make various modifications and changes within the scope of the disclosed technical spirit and claims and their equivalents.

Claims

1. An apparatus for inspecting an electrode assembly, the electrode assembly comprising a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode, the apparatus comprising: a laser irradiation unit configured to irradiate the electrode assembly with a laser beam; an illumination unit configured to illuminate the electrode assembly with light; an image acquisition unit configured to obtain an image of the electrode assembly when the electrode assembly is irradiated by the laser beam and / or the light; as well as A processor is configured to inspect the electrode assembly based on the obtained image.

2. The device according to claim 1, wherein The processor is configured to calculate a phase difference between at least two of the negative electrode, the positive electrode, and the separator based on the obtained image, and to perform a miswinding inspection of the electrode assembly based on the calculated phase difference.

3. The device according to claim 2, wherein The processor is configured to: calculate the thickness of at least one of the negative electrode, the positive electrode and the separator based on the calculated phase difference; calculate the miswinding distance between at least two of the negative electrode, the positive electrode and the separator based on the calculated thickness; and perform the miswinding check based on the calculated miswinding distance.

4. The device according to claim 3, wherein The processor is configured to calculate the stagger distance using trigonometry based on the calculated thickness.

5. The apparatus according to claim 1, wherein The processor is configured to: detect one end of the negative electrode and one end of the positive electrode based on the obtained image; and perform an alignment check of the electrode assembly based on the one end of the negative electrode and the one end of the positive electrode.

6. The device according to claim 5, wherein The electrode assembly is wound in one direction to form an electrode core.

7. The apparatus according to claim 6, wherein The processor is configured to: determine a center point of the pole core based on the obtained image; calculate an arc length between the one end of the negative pole and the one end of the positive pole based on the center point; and perform the alignment check based on the arc length.

8. The apparatus according to claim 6, wherein The obtained image includes at least one of an image of an upper surface of the pole core in a wound state and an image of a side surface of the pole core in an unwound state.

9. The apparatus according to claim 1, wherein The processor is configured to: determine a major diameter of the electrode assembly based on an acquired image including an image of an upper surface of the electrode assembly; and inspecting the major diameter of the electrode assembly based on the determined major diameter.

10. The apparatus according to claim 9, wherein The processor is configured to: extract a pair of first points from the image of the upper surface of the electrode assembly; calculate a first length corresponding to a distance between the pair of first points; extract a pair of second points from the image of the upper surface of the electrode assembly; calculating a second length corresponding to the distance between the pair of second points; And determining a longer length between the first length and the second length as the major diameter of the electrode assembly by comparing the first length with the second length.

11. The apparatus according to claim 1, wherein The processor is configured to examine a volume of the electrode assembly based on the obtained image.

12. The apparatus according to claim 1, wherein The processor is configured to inspect a folding state of at least one of the negative electrode, the positive electrode, and the separator based on the obtained image including an image of an upper surface of the electrode assembly.

13. The apparatus according to claim 1, wherein The image acquisition unit includes a visual camera.

14. The apparatus according to claim 1, wherein The apparatus further includes a lens unit that allows the image acquisition unit to obtain the image of the electrode assembly when the electrode assembly is irradiated by the laser beam and / or the light.

15. The apparatus according to claim 1, wherein The apparatus further includes at least one reflector that reflects the laser beam received from the laser irradiation unit toward the electrode assembly.

16. A method for inspecting an electrode assembly, the method comprising: An apparatus for inspecting an electrode assembly is used to inspect the electrode assembly for at least one of winding, alignment, major diameter, volume, and folding state of the electrode assembly, the electrode assembly comprising a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode, the apparatus comprising: a laser irradiation unit configured to irradiate the electrode assembly with a laser beam; an illumination unit configured to illuminate the electrode assembly with light; an image acquisition unit configured to obtain an image of the electrode assembly irradiated by the laser beam and / or the light; and A processor is configured to inspect the electrode assembly based on the obtained image.

Images