Inspection device for secondary battery

Abstract

An inspection device for a secondary battery, according to an embodiment of the present invention, comprises: a stage for seating a battery cell by including a seating surface and a retroreflective film disposed on the seating surface; and a camera for capturing an image of the battery cell disposed on the retroreflective film. An inspection device for a secondary battery, according to an embodiment of the present invention, may improve the visibility of the outer edge of the battery cell, thereby eliminating the outflow of defective cells caused by erroneous measurements during dimensional measurement.

Description

Secondary battery inspection device

[0001] The present invention relates to a secondary battery inspection device, and more specifically, to a secondary battery appearance inspection device using a retroreflective film.

[0002] Unlike primary batteries, which cannot be recharged, secondary batteries refer to batteries capable of charging and discharging, and are applied not only to portable devices but also to electric vehicles (EVs) and hybrid electric vehicles (HEVs) driven by electric power sources.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, or unit battery cells, is approximately 2.5V to 4.6V. Therefore, if a higher output voltage is required, a battery pack is formed by connecting multiple battery cells in series. Additionally, a battery pack is formed by connecting multiple battery cells in parallel depending on the charge / discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack can be varied depending on the required output voltage or charge / discharge capacity.

[0004] When configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first configure a battery module consisting of at least one battery cell, preferably multiple battery cells, and then use at least one such battery module and add other components to form a battery pack. Here, a battery module refers to a component in which multiple battery cells are connected in series or parallel, and a battery pack may refer to a component in which multiple battery modules are connected in series or parallel to increase capacity and output.

[0005] Battery cells are classified into pouch type, cylindrical type, prismatic type, etc., depending on the shape of the battery case.

[0006] Among these, cylindrical cells offer excellent safety as they primarily utilize a metal case with a cylindrical structure. They also have the advantage of high energy density by housing a jelly-roll type electrode assembly inside the case, and make it easy to configure a large-capacity power storage device by connecting multiple cells in series or parallel.

[0007] In the case of a pouch cell, it is structured to accommodate an electrode assembly including a positive electrode, a negative electrode, and a separator in a pouch-shaped case.

[0008] The manufacturing process of these battery cells includes a process for inspecting the appearance of the manufactured battery cells.

[0009] Generally, the appearance of battery cells is inspected using an appearance inspection device, but there is a problem in that the visibility of the outer edge of the pouch is unclear in conventional appearance inspection devices, making it impossible to measure the dimensions correctly.

[0010] The present invention aims to solve the aforementioned problems by providing an inspection device for a secondary battery that can eliminate the leakage of defective cells caused by mismeasurement during dimensional measurement by improving the visibility of the outer edge portion of the battery cell.

[0011] A secondary battery inspection device according to one embodiment of the present invention comprises: a stage for mounting a battery cell including a mounting surface and a retroreflective film disposed on the mounting surface; and a camera for capturing an image of the battery cell disposed on the retroreflective film.

[0012] In addition, the secondary battery inspection device further includes retroreflective lighting.

[0013] In addition, the retroreflective lighting is positioned in the same direction as the camera.

[0014] In addition, the irradiation direction of the above retroreflective lighting is positioned perpendicular to the retroreflective film.

[0015] In addition, the stage further includes a plurality of mirrors on the edge of the mounting surface.

[0016] Additionally, the mirror includes a pair of first mirrors spaced apart from a pair of long sides of the battery cell; and a pair of second mirrors spaced apart from a pair of short sides of the battery cell.

[0017] In addition, the length of the first mirror is longer than the length of the long side of the battery cell, and the length of the second mirror is formed to be longer than the length of the short side of the battery cell.

[0018] Additionally, the secondary battery inspection device further includes a support frame, the stage is positioned at the bottom of the support frame, and the camera is positioned at the top of the support frame.

[0019] Additionally, the support frame includes a plurality of horizontal frames spaced apart in the height direction and a plurality of vertical frames connected to the horizontal frames.

[0020] Additionally, the secondary battery inspection device further includes a pair of first lights positioned on the outer side of a pair of long sides of the battery cell and extending along the longitudinal direction of the battery cell.

[0021] In addition, the area of ​​the retroreflective film may be larger than the area of ​​the battery cell.

[0022] In addition, the secondary battery inspection device further includes a side mirror disposed above the battery cell; and an upper light disposed above the battery cell and irradiating light in the direction of the side mirror; so that light irradiated from the upper light can be reflected by the side mirror and irradiated onto the battery cell.

[0023] In addition, the secondary battery inspection device further includes two side mirrors positioned to face each other on the upper side of the battery cell; and two upper lights positioned on the upper side of the battery cell to irradiate light in the direction of each side mirror; so that light irradiated from each upper light can be reflected by each side mirror and irradiated onto the battery cell.

[0024] A secondary battery inspection device according to one embodiment of the present invention can improve the visibility of the outer edge portion of a battery cell and eliminate the leakage of defective cells caused by mismeasurement during dimensional measurement.

[0025] FIG. 1 is a drawing showing the interior of a pouch-type battery cell in one embodiment of the present invention, and

[0026] FIG. 2 is a drawing illustrating an electrode assembly in an embodiment of the present invention, and

[0027] FIG. 3 is a plan view of a pouch-type battery cell in one embodiment of the present invention, and

[0028] FIG. 4 is a perspective view of a secondary battery inspection device in one embodiment of the present invention, and

[0029] FIG. 5 is a front view of a secondary battery inspection device in one embodiment of the present invention, and

[0030] FIG. 6 is a partial detailed view of FIG. 4, and

[0031] FIG. 7 is a plan view of a stage on which a battery cell is placed in an embodiment of the present invention, and

[0032] FIG. 8 is a drawing illustrating an image of a battery cell acquired by a secondary battery inspection device according to an embodiment of the present invention.

[0033] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques are not specifically described to avoid the present invention being interpreted ambiguously. Throughout the specification, like reference numerals refer to like components.

[0034] In drawings, thicknesses may be enlarged to clearly represent multiple layers and regions. Throughout the specification, the same reference numerals are used for similar parts. When a part such as a layer, film, region, or plate is described as being "above" another part, this includes not only cases where it is "immediately above" another part, but also cases where there is another part in between. Conversely, when a part is described as being "immediately above" another part, it means that there is no other part in between. Furthermore, when a part such as a layer, film, region, or plate is described as being "below" another part, this includes not only cases where it is "immediately below" another part, but also cases where there is another part in between. Conversely, when a part is described as being "immediately below" another part, it means that there is no other part in between.

[0035] Before describing the secondary battery inspection device (2000) according to one embodiment of the present invention, the battery cell (1000) is described first.

[0036] FIG. 1 is a drawing showing the interior of a pouch-type battery cell in one embodiment of the present invention, FIG. 2 is a drawing showing an electrode assembly in one embodiment of the present invention, and FIG. 3 is a plan view of a pouch-type battery cell in one embodiment of the present invention.

[0037] In this embodiment, the battery cell (1000) may be a pouch-type battery cell (1000). However, the battery cell (1000) is not necessarily provided in a pouch type and may be provided in a prismatic, cylindrical, or various other shapes.

[0038] In this embodiment, the battery cell (1000) includes an electrode assembly (200) and a battery case (100) that accommodates the electrode assembly (200).

[0039] The above battery case (100) is for accommodating an electrode assembly (200) and may be a pouch-type battery case (100).

[0040] In one embodiment of the present invention, the battery case (100) includes a lower case (110) and an upper case (120) covering the lower case (110), and the lower case (110) and the upper case (120) may be formed as a single unit. Additionally, as shown in FIG. 1, the lower case (110) and the upper case (120) may be connected to each other, and the connecting portion of the lower case (110) and the upper case (120) may be bent and formed into a structure that folds along a folding line (190).

[0041] Both the lower case (110) and the upper case (120) may be made of a laminate structure including an inner coating layer, a metal layer, and an outer coating layer.

[0042] In the battery case (100), the inner coating layer is located on the inner side of the battery case (100) based on the metal layer and is in direct contact with the electrode assembly (200), so it must have insulation and electrostatic resistance, and in order to seal it from the outside, it is required to have sealing properties, that is, the sealing portion where the inner layers are heat-bonded together must have excellent heat-bonding strength.

[0043] The material for this inner coating layer can be selected from polyolefin resins such as polypropylene, polyethylene, polyethylene acrylic acid, and polybutylene, polyurethane resins, and polyimide resins, which have excellent chemical resistance and good sealing properties; polypropylene (PP) is most preferable as it has excellent mechanical properties such as tensile strength, stiffness, surface hardness, and impact strength, as well as excellent chemical resistance.

[0044] The metal layer is located between the inner coating layer and the outer coating layer and serves as a barrier layer that prevents moisture or various gases from penetrating into the battery from the outside. As a preferred material for the metal layer in contact with the inner coating layer, a lightweight aluminum (Al) thin film with excellent formability can be used.

[0045] The outer coating layer is located on the outside of the battery case (100) based on the metal layer, and the outer coating layer may use a heat-resistant polymer with excellent tensile strength, moisture resistance, and air permeability resistance to ensure heat resistance and chemical resistance while protecting the electrode assembly (200), and may use, for example, nylon or polyethylene terephthalate, but is not limited thereto.

[0046] A receiving groove (130) may be formed in the lower case (110) and / or the upper case (120). The receiving groove (130) is for receiving an electrode assembly (200) inside the battery case (100), and the receiving groove (130) of the upper case (120) may be located above the receiving groove (130) of the lower case (110), and the electrode assembly (200) may be received within the receiving groove (130) of the upper and lower cases (120, 110).

[0047] Additionally, a protective tape (150) may be attached to the lower case (110) and the upper case (120), respectively. The protective tape (150) is intended to protect the battery case (100) from welding foreign matter generated when forming the welded portion (230) of the electrode assembly (200), and to protect the battery case (100) when forming a sealing portion by heat-fusion of the edges of the battery case (100), and may be attached to the lower case (110) and the upper case (120), respectively.

[0048] In the lower case (110) and upper case (120), a protective tape (150) is attached to the edge portion of the lower case (110) where the weld (230) or electrode leads (231, 232) of the electrode assembly (200) are located. As shown in FIG. 2, the two electrode leads (231, 232) in the electrode assembly (200) may extend in opposite directions from each other, and a protective tape (150) may be attached to each of the edges of the lower case (110) and upper case (120) where the weld (230) or electrode leads (231, 232) are placed.

[0049] Accordingly, a protective tape (150) may be positioned on the edge of the upper case (120) between the top of the receiving groove (130) formed in the upper case (120) and the top of the upper case (120), and between the bottom of the receiving groove (130) and the bottom of the upper case (120), and the protective tape (150) may have a larger area than the weld (230) of the electrode assembly (200) on a flat surface.

[0050] The electrode assembly (200) housed in the battery case (100) may be one of the following: a jelly-roll type electrode assembly having a structure in which a separator is interposed between long sheet-type positive and negative electrodes and then wound; a stack type electrode assembly consisting of unit cells having a structure in which rectangular positive and negative electrodes are stacked with a separator interposed between them; a stack-folding type electrode assembly in which unit cells are wound by a long separator film; and a lamination-stack type electrode assembly in which unit cells are stacked with a separator interposed between them and attached to each other.

[0051] In the present invention, the electrode assembly (200) may include, for example as shown in FIG. 2, an electrode stack (210) and a fixing tape (220) that winds the electrode stack (210).

[0052] The electrode stack (210) may include an anode (211), a cathode (213), and a separator (212) disposed between the anode (211) and the cathode (213), and the electrode stack (210) may be formed such that the length in the electric direction is relatively longer than the length in the width direction.

[0053] The above fixing tape (220) is for fixing an electrode stack (210) in which an anode (211), a separator (212), and a cathode (213) are stacked, and is fixed by winding the outside of the electrode stack (210).

[0054] Additionally, the electrode assembly (200) may include two electrode tabs (201, 202) and two electrode leads (231, 232).

[0055] The electrode tabs (201, 202) are formed to protrude outward from the electrode laminate (210), and one of the two electrode tabs (201, 202) may be an anode tab connected (extended) to the anode (211), and the other electrode tab (202) may be a cathode tab connected (extended) to the cathode (213).

[0056] The electrode leads (231, 232) are connected to the electrode tabs (201, 202) and can be connected by welding to the electrode tabs (201, 202). The material of the electrode leads (231, 232) can be used without special restrictions as long as it is an electrically conductive material. For example, the material of the electrode leads (231, 232) may include at least one of copper (Cu), aluminum (Al), nickel (Ni), iron (Fe), carbon (C), chromium (Cr), and manganese (Mn). However, the electrode leads (231, 232) are not limited to the materials described above and can be selected in various ways considering mechanical strength, flexibility, processability, etc.

[0057] For example, a certain portion of the electrode leads (231, 232) and electrode tabs (201, 202) may be overlapped vertically to form a welded portion (230), and the electrode tabs (201, 202) and electrode leads (231, 232) may be connected to each other by this welded portion (230).

[0058] The formation of the weld (230) can be achieved, for example, by ultrasonic welding. In ultrasonic welding, high-frequency vibrations generated by high-frequency ultrasonic waves of about 20 kHz are applied, and welding is rapidly achieved as vibrational energy is converted into thermal energy by friction at the interface between the electrode tabs (201, 202) and the electrode leads (231, 232). Additionally, as another example, the weld (230) can be formed by laser welding.

[0059] Of the two electrode leads (231, 232), one electrode lead (231) may be a positive lead connected to a positive tab, and the other electrode lead (232) may be a negative lead connected to a negative tab. The positive lead may be made of, for example, aluminum, and the negative lead may be made of, for example, copper or nickel-coated copper, but is not limited thereto.

[0060] Although the two electrode leads (231, 232) shown in FIG. 2 are depicted as being placed on each side of the electrode assembly (200), they may also be placed on one side of the electrode assembly (200) depending on the arrangement of the electrode tabs (201, 202). That is, when the two electrode tabs (201, 202) are placed on one side of the electrode assembly (200), the two electrode leads (231, 232) connected to the electrode tabs (201, 202) may also be formed in the same direction of the electrode assembly (200).

[0061] As shown in FIG. 3, a lead film (155) may be attached to each electrode lead (231, 232). The lead film (155) attached to the electrode lead (231, 232) is positioned between the electrode lead (231, 232) and the battery case (100) to prevent a short circuit from occurring between the electrode lead (231, 232) and the battery case (100) and to improve sealing power, thereby preventing leakage of the electrolyte.

[0062] In one embodiment of the present invention, the remaining portion, excluding the folding portion where the lower case (110) and the upper case (120) constituting the battery case (100) are connected, can be heat-pressed and sealed.

[0063] That is, as shown in FIG. 3, a sealing portion (160) may be placed in the remaining portion of the battery case (100), excluding the folding portion, for sealing purposes.

[0064] The sealing portion (160) can be placed at the edge portion of the battery case (100) and can be formed at the edge excluding the folding portion (folding line (190)) of the battery case (100).

[0065] Specifically, as illustrated in FIG. 3, the battery case (100) may be formed in a roughly rectangular shape on a plane, and the battery case (100) may have a pair of long sides (101) spaced apart from each other and a pair of short sides (102) spaced apart from each other. The pair of short sides (102) may be positioned on the left and right sides of the battery case (100) and may connect the pair of long sides (101) to each other.

[0066] Here, a folding line (190) may be placed on one long side (101), and a sealing portion (160) may be formed on the remaining three sides (101, 102), excluding one side of the folding line (190).

[0067] Hereinafter, the secondary battery inspection device (2000) in this embodiment will be described in detail with reference to FIGS. 4 to 8.

[0068] FIG. 4 is a perspective view of a secondary battery inspection device in one embodiment of the present invention, FIG. 5 is a front view of a secondary battery inspection device in one embodiment of the present invention, FIG. 6 is a partial detail view of FIG. 4, FIG. 7 is a plan view of a stage on which a battery cell is placed in one embodiment of the present invention, and FIG. 8 is a drawing showing an image of a battery cell acquired by a secondary battery inspection device according to one embodiment of the present invention.

[0069] In one embodiment of the present invention, a secondary battery inspection device (2000) may include a stage (2200) on which a battery cell (1000) is placed, a camera (2300) for acquiring an image of the battery cell (2200), a read camera (2510, 2520), a support frame (2100), and lighting (2410, 2411, 2450, 2610, 2620).

[0070] The above stage (2200) may include a mounting surface (2210) on which a battery cell (1000) is mounted, a retroreflective film (2250) disposed on the mounting surface (2210), a mirror (2230, 2231, 2240, 2241) disposed on the outside of the battery cell (1000), and an outer frame (2220) (see FIG. 5).

[0071] The stage (2200) may have a mounting surface (2210), and a battery cell (1000) may be mounted on the mounting surface (2210). The mounting surface (2210) may be formed in the shape of a flat plate, and for example, may be formed in the shape of a rectangle.

[0072] A retroreflective film (2250) may be placed on the mounting surface (2210). Retroreflection refers to light being reflected back in the same direction from which it was incident, and the retroreflective film (2250) is a film that reflects light back in the same direction from which it was incident. The retroreflective film (2250) may be attached to the mounting surface (2210) by means of an adhesive. For this purpose, the retroreflective film (2250) may include an adhesive layer on its rear surface.

[0073] The retroreflective film (2250) is of the glass bead type, so that fine glass beads are uniformly coated on the film so that incident light is totally reflected inside the glass beads and returns to the direction of the light source. The retroreflective film (2250) may include a plurality of layers and may include a glass bead layer.

[0074] As another example, the retroreflective film (2250) is of the prism type, in which triangular pyramid-shaped prisms are regularly coated on the film so that incident light is refracted at the inclined surface of the prism and returns to the direction of the light source.

[0075] The planar surface area of ​​the retroreflective film (2250) may be larger than the planar surface area of ​​the battery cell (1000), specifically larger than the wide surface of the battery cell (1000) (see FIG. 6). The length of the retroreflective film (2250) may be longer than the left-right length including the electrodes (231, 232) of the battery cell (1000), and the width (up-down width) of the retroreflective film (2250) may be larger than the width of the battery cell (1000).

[0076] A battery cell (1000) can be placed on a retroreflective film (2250). As shown in FIGS. 3 and 7, the main surface (widest surface) of the battery cell (1000) can be oriented upward or downward on the retroreflective film (2250) (the battery cell (1000) is laid down).

[0077] The retroreflective film (2250) may have a pair of long sides and a pair of short sides. The pair of long sides of the retroreflective film (2250) may be spaced apart from the pair of long sides (101) of the battery cell (1000) and arranged parallel to the long sides (101).

[0078] A pair of short sides of the retroreflective film (2250) can be spaced apart from a pair of short sides (102) of the battery cell (1000) and arranged parallel to the short sides (102).

[0079] In this embodiment, a retroreflective film (2250) is placed on the mounting surface (2210) where the battery cell (1000) is mounted, thereby eliminating the need for lighting below the battery cell (1000) and improving image visibility for dimensional measurement.

[0080] A mirror (2230, 2231, 2240, 2241) may be placed on the edge of the mounting surface (2210) or the edge of the retroreflective film (2250). The mirror (2230, 2231, 2240, 2241) may include a first mirror (2230, 2231) and a second mirror (2240, 2241). The mirror (2230, 2231, 2240, 2241) may be placed obliquely toward the battery cell (1000).

[0081] The first mirror (2230, 2231) may be spaced apart from each long side (101) of the battery cell (1000) and may extend along the long side (101). The first mirror (2230, 2231) may be positioned parallel to the long side (101) of the battery cell (1000). The length of the first mirror (2230, 2231) may be longer than the long side (101) of the battery cell (1000). Thus, a pair of first mirrors (2230, 2231) may be positioned outside a pair of long sides (101) of the battery cell (1000). Through each first mirror (2230, 2231), the side of each long side (101) of the battery cell (1000) can be inspected.

[0082] The second mirror (2240, 2241) may be spaced apart from each short side (102) of the battery cell (1000) and extend along the short side (102). The second mirror (2240, 2241) may be positioned between the ends of a pair of first mirrors (2230, 2231). The second mirror (2240, 2241) may be positioned parallel to the short side (102) of the battery cell (1000). The length of the second mirror (2240, 2241) may be longer than the short side (102) of the battery cell (1000). Thus, a pair of second mirrors (2240, 2241) may be positioned outside a pair of short sides (102) of the battery cell (1000). Each side of the battery cell (1000) can be inspected on each short side (102) through each second mirror (2240, 2241).

[0083] In this embodiment, a pair of first mirrors (2230, 2231) and a pair of second mirrors (2240, 2241) are arranged on the outside of the battery cell (1000), thereby allowing for simultaneous side inspection of the battery cell (1000).

[0084] The outer frame (2220) may be placed on the outside of the seating surface (2210). The outer frame (2220) may be formed to surround the edges of the seating surface (2210), and may, for example, be formed in a rectangular shape on a plane.

[0085] The upper surface of the outer frame (2220) may be positioned higher than the seating surface (2210), and a light (2410, 2411) may be positioned on the upper surface of the outer frame (2220).

[0086] The support frame (2100) may include a horizontal frame (2110) and a vertical frame (2150).

[0087] Multiple horizontal frames (2110) may be spaced apart along the height direction (Z-axis direction). Each horizontal frame (2110) may be connected to or combined with multiple vertical frames (2150).

[0088] Each horizontal frame (2110) may include a horizontal frame (2111) and a vertical frame (2115).

[0089] The horizontal frame (2111) can be arranged in a first direction (X-axis direction), and the vertical frame (2115) can be arranged in a second direction (Y-axis direction) that is orthogonal to the first direction. The horizontal frame (2111) and the vertical frame (2115) can be formed in the shape of a bar.

[0090] The horizontal frame (2111) and the vertical frame (2115) can be arranged to connect between two vertical frames (2150).

[0091] In this embodiment, each horizontal frame (2110) may include a pair of horizontal frames (2111) arranged parallel to each other and a pair of vertical frames (2115) arranged parallel to each other.

[0092] The stage (2200) can be supported or coupled to the lower side or lowest side horizontal frame (2110) in the support frame (2100).

[0093] The camera (2300) can be supported or coupled to the upper or uppermost horizontal frame (2110) in the support frame (2100).

[0094] A plurality of vertical frames (2150) may be spaced apart from each other, and each vertical frame (2150) may be extended in the height direction (Z-axis direction). In this embodiment, an example in which four vertical frames (2150) are arranged is illustrated.

[0095] The above camera (2300) is intended to acquire an external image of the battery cell (1000) and may be positioned on the upper side of the support frame (2100) or on the uppermost horizontal frame (2110). The camera (2300) can photograph the battery cell (1000) positioned vertically downward, and the camera (2300) may be positioned in a vertical direction (-Z-axis direction). Accordingly, the camera (2300) may be positioned directly above the battery cell (1000).

[0096] The appearance of the battery cell (1000) can be inspected through an image captured by a camera (2300).

[0097] The image captured by the camera (2300) may include mirror (2230, 2231, 2240, 2241) images, and thus side inspection of the battery cell (1000) may also be performed through the image of the camera (2300).

[0098] The lead cameras (2510, 2520) may be cameras for acquiring images of the electrode leads (231, 232) in the battery cell (1000). As shown in FIG. 5, the lead cameras (2510, 2520) are for acquiring images of the electrode leads (231, 232) on both sides of the battery cell (1000), and two lead cameras (2510, 2520) may be arranged horizontally spaced apart from each other on the upper side of the electrode leads (231, 232) on the support frame (2100). One lead camera (2520) may acquire an image of the electrode lead (231) on one side of the battery cell (1000), and the other lead camera (2520) may acquire an image of the electrode lead (232) on the other side of the battery cell (1000).

[0099] In the secondary battery inspection device (2000), the lighting (2410, 2411, 2450, 2610, 2620) may include a first lighting (2410, 2411), a retroreflective lighting (2450), and an upper lighting (2610, 2620).

[0100] The first lights (2410, 2411) may each be placed on the outer side of the long side (101) of the battery cell (1000). Thus, a pair of first lights (2410, 2411) may be placed on the outer side of a pair of long sides (101). A pair of first lights (2410, 2411) may also be placed in a portion of the outer frame (2220) that is positioned in the longitudinal direction (X-axis direction) of the battery cell (1000). A pair of first lights (2410, 2411) may also be placed in a pair of horizontal frames (2111) from a single horizontal frame (2110). The first lights (2410, 2411) may extend in the longitudinal direction (X-axis direction) of the battery cell (1000) and may be bar-shaped lights. The first light (2410, 2411) can be arranged parallel to the longitudinal direction (X-axis direction) of the battery cell (1000).

[0101] The retroreflective light (2450) can be positioned near the camera (2300) on the upper side of the support frame (2100) and can be positioned in the same direction as the camera (2300) is facing. The retroreflective light (2450) can be a light for the retroreflective film (2250). Light from the retroreflective light (2450) can be irradiated in the Z-axis direction, and the irradiation direction of the retroreflective light (2450) can be a direction perpendicular to the retroreflective film (2250).

[0102] Therefore, light irradiated from the light source of the retroreflective light (2450) can be reflected by the retroreflective film (2250) and returned to the light source.

[0103] The retroreflective light (2450) may be coaxial with the camera (2300) and may be positioned in a direction parallel to the camera (2300). The retroreflective film (2250) may emit light by the retroreflective light (2450). In this embodiment, the camera (2300), the retroreflective film (2250), and the retroreflective light (2450) may be located on the same line (coaxial).

[0104] In this embodiment, by arranging a retroreflective light (2450) and a retroreflective film (2250), diffuse reflection caused by the first light (2410, 2411) can be minimized and image visibility for dimensional measurement can be improved. In this embodiment, the light (2410, 2411, 2450) may be, for example, an LED light.

[0105] Upper lights (2610, 2620) can be placed on the upper side of the battery cell (1000). As shown in FIG. 5, two upper lights (2610, 2620) can be placed horizontally spaced apart from each other on the upper side of the battery cell (1000) in the support frame (2100).

[0106] One upper light (2620) can be positioned so as to face the side mirror (A) from the upper side of one electrode lead (231) of the battery cell (1000), and thus, the upper light (2620) can be positioned to irradiate light toward the side mirror (A). Accordingly, light from the upper light (2620) can be reflected from the side mirror (A) and irradiated onto the battery cell (1000), including the side (electrode lead (231) side) of the battery cell (1000).

[0107] Another upper light (2610) can be positioned so as to be directed toward another side mirror (A) from above the other electrode lead (232) of the battery cell (1000), and thus, the upper light (2610) can be positioned to irradiate light toward the other side mirror (A). Accordingly, light from the upper light (2610) can be reflected from the side mirror (A) and irradiated onto the battery cell (1000), including the side (electrode lead (232)) of the battery cell (1000).

[0108] Two side mirrors (A) may be positioned facing each other on both sides of the support frame (2100) to reflect light from the upper light (2610, 2620). Each side mirror (A) can reflect light from the upper light (2610, 2620) so that light is irradiated toward the battery cell (1000), and the side mirror (A) enables an external inspection of the battery cell (1000) from the side.

[0109] In this embodiment, the secondary battery inspection device has the configuration described above, thereby minimizing diffuse reflection during external inspection of the secondary battery and increasing the visibility of the outer edge of the secondary battery, so that the leakage of defective cells can be eliminated.

[0110] FIG. 8 is a drawing illustrating an image of a battery cell acquired by a secondary battery inspection device according to an embodiment of the present invention.

[0111] As shown in FIG. 8, the edge image of the battery cell (1000) appears clearly, so the risk of mismeasurement during dimensional measurement can be eliminated.

[0112] Although the present invention has been described with reference to preferred embodiments as described above, it is not limited to the aforementioned embodiments, and various changes and modifications may be made by those skilled in the art within the scope of the invention without departing from the spirit of the invention.

[0113] The present invention can provide a secondary battery inspection device that can eliminate the leakage of defective cells caused by mismeasurement during dimensional measurement by improving the visibility of the outer edge portion of a battery cell.

Claims

1. A stage for mounting a battery cell, comprising a mounting surface and a retroreflective film disposed on the mounting surface; and A camera for capturing an image of the battery cell disposed on the retroreflective film; A secondary battery inspection device including 2. In Paragraph 1, A secondary battery inspection device including additional retroreflective lighting.

3. In Paragraph 1, The above retroreflective lighting is a secondary battery inspection device positioned in the same direction as the camera.

4. In Paragraph 1 A secondary battery inspection device in which the irradiation direction of the above retroreflective lighting is arranged in a direction perpendicular to the above retroreflective film.

5. In Paragraph 1, The above stage is a secondary battery inspection device that further includes a plurality of mirrors on the edge of the mounting surface.

6. In Paragraph 5, A secondary battery inspection device comprising: a pair of first mirrors spaced apart from a pair of long sides of the battery cell; and a pair of second mirrors spaced apart from a pair of short sides of the battery cell.

7. In Paragraph 6, A secondary battery inspection device in which the length of the first mirror is longer than the length of the long side of the battery cell, and the length of the second mirror is longer than the length of the short side of the battery cell.

8. In Paragraph 1, Including more support frames, The above stage is positioned at the bottom of the support frame, and The above camera is a secondary battery inspection device positioned on the upper part of the support frame.

9. In Paragraph 8, The above support frame is a secondary battery inspection device comprising a plurality of horizontal frames spaced apart in the height direction and a plurality of vertical frames connected to the horizontal frames.

10. In Paragraph 1, A pair of first lights disposed on the outer side of a pair of long sides of the battery cell and extending along the longitudinal direction of the battery cell; A secondary battery inspection device further comprising 11. In Paragraph 1, A secondary battery inspection device in which the area of ​​the above retroreflective film is larger than the area of ​​the above battery cell.

12. In Paragraph 1, A side mirror positioned on the upper side of the battery cell; and An upper light positioned above the battery cell and irradiating light in the direction of the side mirror; A secondary battery inspection device that further includes light irradiated from the upper light source, which is reflected by the side mirror and irradiated onto the battery cell.

13. In Paragraph 1, Two side mirrors positioned facing each other on the upper side of the battery cell; and Two upper lights positioned above the battery cell and irradiating light in the direction of each side mirror; A secondary battery inspection device that further includes light irradiated from each of the above upper lights, which is reflected by each of the above side mirrors and irradiated onto the battery cell.

Images