Unit cell inspection device

Abstract

The present invention relates to a unit cell inspection device, the unit cell inspection device including: a transport unit configured to transport a plurality of unit cells, each having an electrode, in a predetermined transport direction and including a plurality of transport rollers arranged along the transport direction; and an optical inspection unit configured to optically sense an inspection target unit cell, which is a unit cell positioned at a predetermined inspection position among the plurality of unit cells transported by the transport unit, wherein each of the unit cells further includes an electrode tab extending from the electrode and exposed to an outside of a separator provided in each of the unit cells, the optical inspection unit configured to set an area including an area where at least a portion of the electrode tab is located at the inspection position as a Region of Interest (ROI), and an adjacent transport roller, which is a transport roller disposed adjacent to the Region of Interest among the plurality of transport rollers, may be configured not to overlap the Region of Interest.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0020455 filed on February 16, 2022 and Korean Patent Application No. 10-2023-0019638 filed on February 14, 2023, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a unit cell inspection device. [Background technology]

[0003] In general, a secondary battery means a battery that can be charged and discharged, unlike a primary battery that cannot be charged, and is widely used in electronic devices such as mobile phones, laptops, and camcorders, electric vehicles, etc. In particular, lithium secondary batteries have a larger capacity and higher energy density than nickel-cadmium batteries or nickel-metal hydride batteries, and therefore their use is rapidly increasing.

[0004] Depending on the shape of the battery case, secondary batteries can be classified into cylindrical batteries and prismatic batteries in which the electrode assembly is housed in a cylindrical or prismatic metal can, and pouch batteries in which the electrode assembly is housed in a pouch-type case made of an aluminum laminate sheet.

[0005] FIG. 1 is a diagram showing an example of a pouch-type secondary battery. The pouch-type secondary battery 1 includes an electrode assembly 2 formed by alternately stacking electrodes and separators, and a pouch 20 in which the electrode assembly 2 is housed. Electrode tabs 15 may be connected to the electrodes of the electrode assembly 2. The electrode tabs 15 may be welded to each other in a predetermined area and then connected to an electrode lead 17. The pouch 20 includes a concave cup portion 21 for housing the electrode assembly 2. The pouch 20 may have one or two cup portions 21. FIG. 1 illustrates a pouch 20 including a left cup portion and a right cup portion. A peripheral portion 23 (terrace) is formed around the cup portion 21 by sealing.

[0006] Meanwhile, during the process of manufacturing the electrode assembly 2, the unit cells constituting the electrode assembly 2 may be optically inspected for abnormalities (e.g., whether the electrode tabs of the unit cells are broken). This may be done by photographing the unit cells and then analyzing the photographed images. However, if an object to be inspected for abnormalities (e.g., the electrode tabs of the unit cells) is hidden by other objects during the process of acquiring a photographed image of the unit cells, it may be difficult to analyze the acquired image to determine whether an abnormality exists. For example, if rollers disposed under the unit cells for transporting the unit cells hide the electrode tabs of the unit cells, it may be difficult to accurately acquire an image of the electrode tabs, and as a result, it may be difficult to reliably determine whether an abnormality exists in the electrode tabs from the acquired image. Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a unit cell inspection device capable of accurately determining whether an inspection target of a unit cell has an abnormality by preventing the inspection target of the unit cell from being obscured by other objects during the process of acquiring an image of the unit cell for inspection of the unit cell. [Means for solving the problem]

[0008] In one example, a unit cell inspection device may include a transport unit configured to transport a plurality of unit cells, each having an electrode, in a predetermined transport direction and including a plurality of transport rollers arranged along the transport direction, and an optical inspection unit configured to optically sense an inspection target unit cell, which is a unit cell that is to be positioned at a predetermined inspection position among the plurality of unit cells transported by the transport unit, wherein each of the unit cells further includes an electrode tab extending from the electrode and exposed to an outside of a separator provided in each of the unit cells, and the optical inspection unit may be configured to set an area including an area where at least a portion of the electrode tab is located at the inspection position as a Region of Interest (ROI), and an adjacent transport roller, which is a transport roller disposed adjacent to the Region of Interest among the plurality of transport rollers, may be configured not to overlap the Region of Interest.

[0009] In another example, the region of interest may be set based on a region in which the electrode tab is located at the inspection position when the unit cell is normally moved and a region in which the electrode tab is located at the inspection position when the unit cell is obliquely moved.

[0010] In yet another example, the region of interest may be set to include an area extending outside the separation membrane by a first distance in the longitudinal direction at an end of the longitudinal side of the separation membrane, where the electrode tab begins to be exposed when the electrode tab is positioned in the longitudinal direction of the adjacent transport roller perpendicular to the transport direction, and an area extending inside the separation membrane by a second distance in the opposite direction to the longitudinal direction at the end.

[0011] In yet another example, the first distance may be a length defined in the longitudinal direction and may be set based on an exposed length of the electrode tab exposed to the outside of the separation membrane at an end of the separation membrane.

[0012] In yet another example, the first distance may be between 15 mm and 30 mm.

[0013] In yet another example, the second distance may be a length defined in the longitudinal direction and may be set based on an exposed length of the electrode tab exposed to the outside of the separation membrane at an end of the separation membrane and a predetermined margin distance.

[0014] In yet another example, the second distance may be between 15 mm and 30 mm.

[0015] In yet another example, the first distance may be less than or equal to the second distance.

[0016] In yet another example, the adjacent transport rollers may be provided with a length that does not encroach on the region of interest.

[0017] In yet another example, the optical inspection unit may include a lamp arranged to irradiate light toward the unit cell to be inspected and disposed above the unit cell to be inspected, and a camera arranged below the unit cell to be inspected and disposed to photograph the unit cell to be inspected while being irradiated with light by the lamp.

[0018] In yet another example, the optical inspection unit may further include a reflector that changes the imaging path of the camera to an orthogonal direction.

[0019] In yet another example, the electrode tabs may include a positive electrode tab and a negative electrode tab extending from a positive electrode, which is one of the electrodes, and a negative electrode, which is the other of the electrodes, in a longitudinal direction of the adjacent transfer roller perpendicular to the transfer direction and in an opposite direction thereto, and the optical inspection unit may include a positive electrode tab inspection unit that sets an area including an area where at least a portion of the positive electrode tab is located at the inspection position as a region of interest and optically inspects the positive electrode tab, and a negative electrode tab inspection unit that sets an area including an area where at least a portion of the negative electrode tab is located at the inspection position as a region of interest and optically inspects the negative electrode tab.

[0020] In yet another example, the adjacent transport roller may be disposed to at least partially overlap the unit cell to be inspected that is to be positioned at the inspection position.

[0021] In yet another example, a distance between the adjacent transfer roller and another transfer roller disposed closest to the adjacent transfer roller may be shorter than a width of the unit cell defined in the transfer direction. Effect of the Invention

[0022] According to the present invention, since the adjacent transport rollers do not intrude into the region of interest, it is possible to eliminate the problem of being unable to determine or erroneously determining whether or not there is an abnormality in the electrode tab due to interference from the transport rollers when processing the region of interest in an image acquired by the optical inspection unit. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a diagram showing an example of a pouch-type secondary battery. [Diagram 2] 1 is a diagram showing a unit cell inspection device according to a first embodiment of the present invention; [Diagram 3] 3 is a plan view of the inspection device of FIG. 2 as seen from above. [Figure 4] 13 is a bottom view of a unit cell to be inspected positioned at an inspection position, illustrating a case in which a transport roller covers an electrode tab in a region of interest; FIG. [Diagram 5] 13 is a bottom view of a unit cell to be inspected positioned at an inspection position, illustrating a case where a transport roller does not cover an electrode tab in a region of interest; FIG. [Figure 6] 13 is a bottom view of a unit cell to be inspected located at an inspection position, illustrating a case in which a separation film is obliquely transported; FIG. [Figure 7] 3 is a diagram specifically illustrating an optical inspection unit of the inspection device of FIG. 2. [Figure 8] FIG. 11 is a diagram showing a unit cell inspection device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and should not be construed as being limited to the following embodiments.

[0025] In order to clearly explain the present invention, detailed descriptions of parts that are not relevant to the description or of related known technologies that may obscure the gist of the present invention will be omitted, and in this specification, when adding reference numbers to components in each drawing, the same or similar reference numbers will be used for the same or similar components throughout the specification.

[0026] Furthermore, the terms and words used in this specification and the claims should not be interpreted limited to their ordinary and dictionary meanings, but should be interpreted in a way that is consistent with the technical ideas of the present invention, based on the principle that the inventor himself / herself can appropriately define the concepts of terms in order to explain the invention in the best possible manner.

[0027] Example 1 Fig. 2 is a diagram showing a unit cell inspection apparatus according to a first embodiment of the present invention, and Fig. 3 is a plan view of the inspection apparatus of Fig. 2 as viewed from above. The apparatus according to the first embodiment of the present invention is an apparatus for inspecting a unit cell 10, and may be, for example, an apparatus for inspecting electrode tabs 15a, 15b of the unit cell 10. The inspection apparatus according to this embodiment may include a transfer unit 110 for transferring the unit cell 10, and an optical inspection unit 130 for inspecting the unit cell 10.

[0028] The transfer unit 110 may be provided to transfer the unit cells 10 in a predetermined transfer direction (D1). For example, the transfer unit 110 may include a belt conveyor (not shown) for transferring the unit cells 10. The belt conveyor may include a drive roller (not shown) for providing a driving force, and a circular belt (not shown) circulated by the drive roller. The unit cells 10 may be placed on the belt circulated by the drive roller and transferred.

[0029] The conveying unit 110 may be embodied in a manner of conveying a separation film 19 as shown in FIG. 2. The electrode assembly 2 (see FIG. 1) constituting the battery may be of various types. For example, the electrode assembly 2 may be of a stack-folding type. The stack-folding type electrode assembly 2 may be manufactured by folding a unit cell 10 (full cell or bi-cell) in which electrodes 11a, 11b and a separation film 13 are stacked in a certain order, using a separation film 19. The conveying unit 110 may convey the separation film 19 to convey the unit cell 10 placed on the separation film 19 (see FIG. 3). To this end, the conveying unit 110 may include a driving roller (not shown) for unwinding the separation film 19 from a roller (not shown) around which the separation film 19 is wound. Since the separation film 19 also serves as a separation film, hereinafter, the separation film 19 and the separation film 13 included in the unit cell 10 may all be referred to as a separation film. For reference, the inspection device of this embodiment may be located before the folding device or as part of the folding device.

[0030] The transport section 110 may include a plurality of transport rollers 111 arranged along the transport direction (D1). The transport rollers 111 may support the separation film 19 during transport of the separation film 19. To this end, the transport rollers 111 may be disposed below the separation film 19. The transport rollers 111 may be idle rollers to which no driving force is provided.

[0031] The optical inspection unit 130 may be provided to optically sense the unit cell 10' to be inspected (see FIG. 2). The optical inspection unit 130 may be provided to capture and process an image of the unit cell 10' to be inspected to inspect whether or not there is an abnormality in the unit cell 10' to be inspected. To this end, the optical inspection unit 130 may include a camera 133 (see FIG. 7), for example, a CCD camera, for photographing the unit cell 10' to be inspected. Here, the unit cell 10' to be inspected may be a unit cell 10 to be positioned at a predetermined inspection position (I) (see FIG. 2) among the plurality of unit cells 10 transferred by the transfer unit 110. The inspection position (I) may be a position where the camera 133 of the optical inspection unit 130 can photograph the unit cell 10.

[0032] The optical inspection unit 130 may set an area including the area where the electrode tabs 15a, 15b are located at the inspection position (I) as a region of interest (R) (see FIG. 5) (ROI). The region of interest (R) may be an area where processing (image processing) is required to determine the presence or absence of abnormality in an image captured by the camera 133 of the optical inspection unit 130. The optical inspection unit 130 can inspect the presence or absence of abnormality of the electrode tabs 15a, 15b by setting an area including the area where the electrode tabs 15a, 15b are located at the inspection position (I) as the region of interest (R). If the presence or absence of abnormality can be determined with only a portion of the electrode tabs 15a, 15b, the region of interest (R) may be set to include an area where a portion of the electrode tabs 15a, 15b is located. Here, the electrode tabs 15a, 15b may extend from the electrodes 11a, 11b and be provided so as to be exposed to the outside of a separation film 13 that is provided in the unit cell 10 and separates the electrodes 11a, 11b. For example, FIG. 3 illustrates electrode tabs 15a, 15b that are exposed to the outside of the separation film 13 of the unit cell 10 and also exposed to the outside of a separation film 19. For reference, in FIG. 5 described later, a region of interest (R) is exemplarily set to include a part of one electrode tab 15a of the two electrode tabs 15a, 15b.

[0033] When the optical inspection unit 130 photographs the unit cell 10' to be inspected, the transport roller 111' of the transport unit 110 may interfere with the photographing of the optical inspection unit 130. For example, the optical inspection unit 130 may photograph the unit cell 10' to be inspected from below the unit cell 10' to be inspected. However, if the transport roller 111' is formed long in the longitudinal direction (D2) of the transport roller 111' as shown in FIG. 4, the transport roller 111' may hide a part of the electrode tab 15a in the region of interest (R') when the optical inspection unit 130 photographs. The electrode tabs 15a, 15b may be folded inwardly into the separation film 19 due to collision with other parts during transportation, and if the transport roller 111' hides the electrode tab 15a in the region of interest (R'), it may be difficult for the optical inspection unit 130 to reliably obtain an image of the electrode tab 15a folded inwardly into the separation film 19. Such problems due to hiding (or overlapping) may be more pronounced during skewed transport, as described below. For example, the degree to which the transport roller hides the region of interest may be greater during skewed transport compared to normal transport. Figure 4 is a bottom view of a unit cell to be inspected located at an inspection position, illustrating a case in which the transport roller hides the electrode tabs in the region of interest.

[0034] In the case of the unit cell inspection apparatus according to the present embodiment, in order to solve the above problem, the adjacent transfer roller 111a, which is the transfer roller 111 disposed adjacent to the region of interest (R) among the transfer rollers 111, may be provided so as not to overlap the region of interest (R) as shown in FIG. 5. For example, the adjacent transfer roller 111a may be provided so as to have a length that does not invade the region of interest (R). The length of the transfer roller 111a in FIG. 5 may be shorter than the length of the transfer roller 111' in FIG. 4. For example, in the case where the electrode tabs 15a and 15b are provided so as to be exposed in the longitudinal direction (D2) and the opposite direction of the adjacent transfer roller 111a (and two regions of interest are set corresponding to the electrode tabs as in Example 2 described later), the length of the adjacent transfer roller 111a in FIG. 5 may be shorter than the length of the transfer roller 111' in FIG. 4 by 60 mm. FIG. 5 is a bottom view of a unit cell to be inspected located at an inspection position, illustrating a case where the transfer roller does not hide the electrode tabs in the region of interest. For reference, the presence or absence of overlap may be determined in the lamination direction of the electrode and the separator or in a direction perpendicular to the separator (the up-down direction based on FIG. 2).

[0035] In the unit cell inspection device according to this embodiment, since the adjacent transport roller 111a does not invade the region of interest (R), it is possible to eliminate the problem of not being able to determine or erroneously determining whether or not there is an abnormality in the electrode tabs 15a, 15b due to interference from the transport roller 111 when processing the region of interest (R) in the image acquired by the optical inspection unit 130.

[0036] Meanwhile, in this embodiment, the adjacent transport roller 111a may be disposed to at least partially overlap the unit cell 10' to be inspected that is to be positioned at the inspection position (I) in order to solve the following problem: FIG 5 illustrates an example of the adjacent transport roller 111a that partially overlaps the electrodes 11a, 11b and the separator 13 of the unit cell 10' to be inspected.

[0037] The separation film 19 is likely to sag vertically downward during the process. During the process of manufacturing a stack-folding type electrode assembly, tension on the separation film may be interrupted during the folding process (for example, when preparing to fold the next electrode assembly after one electrode assembly is completed). When such an interruption occurs, the tension applied to the separation film weakens, and the separation film is likely to sag downward. In this case, if the supply of the separation film continues upstream of the inspection device, this sagging may become more pronounced. Furthermore, if unit cells are placed on the separation film, the weight of the unit cells may cause the separation film to sag more pronouncedly.

[0038] If such sagging occurs, the captured image will be distorted, making it impossible to accurately inspect the object to be inspected. In addition, the electrode assembly may become wrinkled or deformed. In addition, in the captured image, the separation film may be shown in a light color and the electrodes in a dark color, so when a change from dark to light is detected (for this reason, a trigger sensor is usually used), it is recognized that the unit cell has passed (or arrived), and it may be considered to start capturing images (after a predetermined time has passed). However, if the separation film sags, problems may occur with this recognition as well, which may cause problems with the capture time.

[0039] In order to solve this problem, that is, to prevent the separation film 19 from sagging, the adjacent transfer roller 111a of this embodiment may be disposed to at least partially overlap the unit cell 10' to be inspected as shown in FIG. 5, and may be provided to support the separation film 19. Alternatively, the interval between the transfer rollers 111 may be set narrower to support the separation film 19. For example, the interval between the adjacent transfer roller 111a and another transfer roller 111 (or another adjacent transfer roller) disposed most adjacent to the adjacent transfer roller 111a may be shorter than the width of the unit cell defined in the transfer direction (D1) (e.g., the width in the left-right direction of the electrode with reference to FIG. 5). This can minimize the area of ​​the separation film 19 that is not supported by the transfer roller. Alternatively, in order to support the separation film 19, the adjacent transfer roller 111a may have a maximum length (see FIG. 5) that does not overlap the region of interest (or is spaced apart from the region of interest by a predetermined extra distance).

[0040] As described above, the unit cell inspection apparatus of this embodiment can prevent both the sagging of the separation film and the interference of the photographed image caused by the adjacent transport rollers.

[0041] On the other hand, the region of interest (R) may be set as follows.

[0042] First, the region of interest (R) may be set in consideration of the region (A1) where the electrode tab 15a is located at the inspection position (I) (see FIG. 2) during normal transport of the unit cell 10, as shown in FIG 5. Normal transport refers to a case where the separation film 19 is transported along a predetermined path, and may be contrasted with oblique transport, which is a case where the separation film 19 is transported deviating from the predetermined path. As shown in FIG 5, the electrode tab 15a may be located in the A1 region at the inspection position (I) during normal transport.

[0043] However, the optical inspection unit 130 can determine that an abnormality has occurred in the electrode tab 15a when a portion of the electrode tab 15a exposed to the outside of the separation film 19 is folded outward from the separation film 19, or when a portion of the electrode tab 15a exposed to the outside of the separation film 19 is folded inward from the separation film 19. For such a determination, the region of interest (R) may be set to include all of the region where the portion of the electrode tab 15a exposed to the outside of the separation film 19 is located and the region where the folded portion is located when the portion of the electrode tab 15a exposed to the outside of the separation film 19 is folded inward from the separation film 19.

[0044] Secondly, the region of interest (R) may be set in consideration of at least one of a first distance (L1) and a second distance (L2) described below. When the electrode tab 15a is disposed in a longitudinal direction (D2) of the adjacent transport roller 111a perpendicular to the transport direction (D1) of the unit cell 10, the electrode tab 15a begins to be exposed to the outside of the separation film 19 at an end 19a of the separation film 19 on the longitudinal direction (D2) side. The first distance (L1) is a distance set in the longitudinal direction (D2) at the end 19a of the separation film 19 as described above, and the second distance (L2) is a distance set in the opposite direction to the longitudinal direction (D2) at the end 19a of the separation film 19. The region of interest (R) may be defined to include an area extending outside the separation film 19 by a first distance (L1) at the end 19a of the separation film 19, and an area extending inside the separation film 19 by a second distance (L2) at the end 19a of the separation film 19.

[0045] The first distance (L1) may be set based on the exposed length (h1) of the electrode tab 15a exposed to the outside of the separation film 19 at the end 19a of the separation film 19. The exposed length (h1) of the electrode tab 15a may be a length defined in the longitudinal direction (D2). For example, the first distance (L1) may be set to be the same as the exposed length (h1) of the electrode tab 15a so that the exposed portion of the electrode tab 15a located at the inspection position (I) (see FIG. 2) is included in the region of interest (R). Alternatively, in consideration of the fact that the electrode tab 15a may be bent or misaligned during oblique transport, or that a marginal area may be required during image processing, the first distance (L1) may be set to be longer than the exposed length (h1) as shown in FIG. 5, that is, by further considering a predetermined marginal distance. For example, if the exposed length (h1) of the electrode tab 15a is 15 mm, the first distance (L1) may be set to be 15 mm to 30 mm.

[0046] The second distance (L2) may be set based on the exposed length (h1) of the electrode tab 15a exposed outside the separation film 19 at the end 19a of the separation film 19 and a predetermined marginal distance. When the exposed portion of the electrode tab 15a is completely folded inside the separation film 19, the exposed portion of the electrode tab 15a may be located inside the separation film 19 by the exposed length (h1) at the end 19a of the separation film 13. In order to be able to inspect all such cases, the second distance (L2) may be set taking into consideration the exposed length (h1) of the electrode tab 15a. In addition, taking into consideration the positional deviation of the electrode tab 15a, marginal areas during image processing, and the like, the second distance (L2) may be set taking into consideration both the exposed length (h1) of the electrode tab 15a and a predetermined marginal distance. For example, when the exposed length (h1) of the electrode tab 15a is 15 mm, the second distance (L2) may be set to 15 mm to 30 mm. On the other hand, the second distance (L2) may be greater than or equal to the first distance (L1).

[0047] Third, the region of interest (R) may be set based on the region where the electrode tab 15a is located at the inspection position (I) during normal transfer of the unit cell 10 and the region where the electrode tab 15a is located at the inspection position (I) during oblique transfer of the unit cell 10. The separation film 19 may be transferred in a twisted state for various reasons during transfer, as shown in FIG. 6. In FIG. 6, reference numeral 19a indicates an end of the separation film 19 during normal transfer, and reference numeral 19a' indicates an end of the separation film 19 during oblique transfer. In order to inspect the presence or absence of an abnormality in the electrode tab 15a even if the position of the electrode tab 15a is changed due to such twisting, the region of interest (R) may be set in consideration of both the position of the electrode tab 15a during normal transfer (see A1 in FIG. 5) and the position of the electrode tab 15a during oblique transfer (see A2 in FIG. 6). As a result, for example, at least a part of the electrode tab may be included in the region of interest even during oblique transfer, and the transfer roller may not overlap the region of interest set in this manner.

[0048] Meanwhile, the optical inspection unit 130 may be configured as follows, as shown in Fig. 7. Fig. 7 is a diagram specifically illustrating the optical inspection unit of the inspection apparatus of Fig. 2.

[0049] The optical inspection unit 130 may include a lamp 131 arranged to irradiate light toward the unit cell 10' to be inspected. The lamp 131 may highlight the unit cell 10' to be inspected so that a camera 133 (described later) can clearly photograph the unit cell 10' to be inspected. The lamp 131 may be a back light. The lamp 131 may be disposed above the unit cell 10' to be inspected. The optical inspection unit 130 may include a flat dome 137 to irradiate the unit cell 10' to be inspected uniformly with light at various angles.

[0050] The optical inspection unit 130 may include a camera 133 that is provided to capture an image of the unit cell 10′ to be inspected while being irradiated with light by the lamp 131. The camera 133 may be a CCD camera. The camera 133 may be disposed below the unit cell 10′ to be inspected, opposite the lamp 131. With this arrangement, the unit cell 10′ to be inspected may be located between the camera 133 and the lamp 131.

[0051] The optical inspection unit 130 may include a reflector 135 that changes the imaging path of the camera 133 to an orthogonal direction. By using the reflector 135, the degree of freedom of the position of the camera 133 can be increased, and the vertical size of the inspection device can also be reduced.

[0052] Example 2 8 is a diagram showing a unit cell inspection apparatus according to a second embodiment of the present invention. The inspection apparatus of the second embodiment differs from the inspection apparatus of the first embodiment in that it includes two inspection units. The following describes the inspection apparatus of the second embodiment, focusing on such differences. For reference, the matters described in the first embodiment may be applied in the same or similar manner to the second embodiment.

[0053] In this embodiment, the electrode tabs 15a, 15b of the unit cell 10' to be inspected may include a positive electrode tab and a negative electrode tab extending from one of the electrodes 11a, 11b, which is a positive electrode, and the other, which is a negative electrode, in the longitudinal direction (D2) of the adjacent transport roller 111a and the opposite direction thereto. That is, the positive electrode tab and the negative electrode tab may protrude in opposite directions to each other.

[0054] The optical inspection unit 130 of this embodiment may include a positive electrode tab inspection unit 130L for inspecting the positive electrode tabs and a negative electrode tab inspection unit 130R for inspecting the negative electrode tabs so as to inspect all the positive electrode tabs and negative electrode tabs that protrude in opposite directions.

[0055] The positive electrode tab inspection unit 130L can optically inspect the positive electrode tab by setting an area including an area where at least a part of the positive electrode tab is located at the inspection position (I) as a region of interest (R). The positive electrode tab inspection unit 130L may include a lamp 131L, a flat dome 137L, a reflector 135L, and a camera 133L, similar to those described in the first embodiment.

[0056] The negative electrode tab inspection unit 130R can optically inspect the negative electrode tab by setting an area including an area where at least a portion of the negative electrode tab is located at the inspection position (I) as a region of interest (R). The negative electrode tab inspection unit 130R may include a lamp 131R, a flat dome 137R, a reflector 135R, and a camera 133R, similar to those described in the first embodiment.

[0057] The above description is merely an illustrative example of the technical concept of the present invention, and various modifications and variations can be made by those having ordinary knowledge in the technical field to which the present invention pertains without departing from the essential characteristics of the present invention.

[0058] Therefore, the embodiments disclosed in the present invention are intended to explain, not to limit, the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such embodiments.

[0059] The scope of protection of the present invention should be interpreted according to the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims

1. a transfer unit including a plurality of transfer rollers arranged along a predetermined transfer direction, the transfer rollers being provided to transfer a plurality of unit cells each including an electrode in a predetermined transfer direction; an optical inspection unit configured to optically sense an inspection target unit cell, the inspection target unit cell being a unit cell positioned at a predetermined inspection position among the plurality of unit cells transferred by the transfer unit, Each of the unit cells further includes an electrode tab extending from the electrode and exposed to an outside of a separator provided in each of the unit cells, the optical inspection unit is configured to set a region including a region in which at least a portion of the electrode tab is located at the inspection position as a region of interest (ROI); The unit cell inspection apparatus, wherein an adjacent transport roller, which is a transport roller disposed adjacent to the region of interest among the plurality of transport rollers, is installed so as not to overlap the region of interest.

2. The region of interest is 2 . The unit cell inspection apparatus of claim 1 , wherein the inspection position is set based on an area where the electrode tab is located at the inspection position when the unit cell is normally transferred and an area where the electrode tab is located at the inspection position when the unit cell is obliquely transferred.

3. The region of interest is 2. The unit cell inspection device of claim 1, wherein the electrode tab begins to be exposed when the electrode tab is disposed in a longitudinal direction of the adjacent transport roller perpendicular to the transport direction, the electrode tab being configured to include a region extending outwardly of the separator by a first distance in the longitudinal direction at an end of the longitudinal direction of the separator, and a region extending inwardly of the separator by a second distance in an opposite direction to the longitudinal direction at the end.

4. The first distance is:

4. The unit cell inspection device of claim 3, wherein the length defined in the longitudinal direction is set based on an exposed length of the electrode tab exposed to the outside of the separator at an end of the separator.

5. The unit cell inspection apparatus of claim 3 , wherein the first distance is between 15 mm and 30 mm.

6. The second distance is:

4. The unit cell inspection device of claim 3, wherein the length defined in the longitudinal direction is set based on an exposed length of the electrode tab exposed outside the separator at an end of the separator and a predetermined margin distance.

7. The unit cell inspection apparatus of claim 3 , wherein the second distance is between 15 mm and 30 mm.

8. The unit cell inspection apparatus of claim 3 , wherein the first distance is equal to or less than the second distance.

9. The adjacent transport rollers are The unit cell inspection apparatus of claim 1 , wherein the unit cell inspection apparatus is provided to have a length that does not encroach on the region of interest.

10. The optical inspection unit includes: a lamp disposed above the unit cell to irradiate light toward the unit cell; 2. The unit cell inspection apparatus according to claim 1, further comprising: a camera disposed below the unit cell to be inspected, the camera being provided to photograph the unit cell to be inspected while being irradiated with light by the lamp.

11. The optical inspection unit includes: The unit cell inspection device according to claim 10 , further comprising a reflector for changing an imaging path of the camera in an orthogonal direction.

12. The electrode tab is a positive electrode tab and a negative electrode tab extending from a positive electrode, which is one of the electrodes, and a negative electrode tab extending from a negative electrode, which is the other of the electrodes, in a longitudinal direction of the adjacent transport roller perpendicular to the transport direction and in a direction opposite thereto; The optical inspection unit includes: a positive electrode tab inspection unit that sets an area including an area where at least a portion of the positive electrode tab is located at the inspection position as a region of interest and optically inspects the positive electrode tab; a negative electrode tab inspection unit that sets an area including an area where at least a portion of the negative electrode tab is located at the inspection position as a region of interest and optically inspects the negative electrode tab.

13. The unit cell inspection apparatus of claim 1 , wherein the adjacent transport roller is disposed to at least partially overlap the unit cell to be inspected that is to be positioned at the inspection position.

14. 14. The unit cell inspection apparatus of claim 1, wherein a distance between the adjacent transfer roller and another transfer roller disposed closest to the adjacent transfer roller is shorter than a width of the unit cell defined in the transfer direction.

Images