Inspection apparatus and inspection method

Abstract

A technical idea of the present invention provides an inspection apparatus comprising: an inspection jig that includes a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements, and is configured to generate thickness data for the thickness of a battery cell while the battery cell provided between the first jig and the second jig is in contact with the first jig and the second jig; and a processor configured to detect a bending dimension and a bending shape of the battery cell on the basis of first pressure data generated by the plurality of first pressure sensing elements, second pressure data generated by the plurality of second pressure sensing elements, and the thickness data.

Description

Inspection device and inspection method

[0001] The present invention relates to an inspection device and an inspection method, and more particularly, to an inspection device and an inspection method configured to inspect a battery cell.

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2024-0120628, filed September 5, 2024, the entire contents of which are incorporated herein by reference.

[0003] With technological developments and growing demand for mobile devices, the demand for secondary batteries is also rapidly increasing. Lithium secondary batteries, in particular, are widely used as a power source for various mobile devices and electronic products due to their high energy density, high operating voltage, and excellent storage and lifespan characteristics. Recently, as the application fields of secondary batteries have expanded, the demand for higher-capacity secondary batteries has skyrocketed. This growing demand for higher-capacity secondary batteries has led to increasing length and width of the battery cells that make up the secondary batteries. As cell length and width increase, cell bending defects are becoming more severe.

[0004] The technical idea of ​​the present invention is to provide a test device and a test method configured to test a battery cell.

[0005] In order to solve the above-described problem, the technical idea of ​​the present invention provides an inspection device including: an inspection jig including a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements, and configured to generate thickness data for a thickness of a battery cell provided between the first jig and the second jig while the battery cell is in contact with the first jig and the second jig; and a processor configured to detect a bending dimension and a bending shape of the battery cell based on the first pressure data generated from the plurality of first pressure sensing elements, the second pressure data generated from the plurality of second pressure sensing elements, and the thickness data.

[0006] In exemplary embodiments, each of the plurality of first pressure sensing elements is characterized in that it is aligned with a corresponding one of the plurality of second pressure sensing elements.

[0007] In exemplary embodiments, the plurality of first pressure sensing elements are arranged in a two-dimensional array form, and the plurality of second pressure sensing elements are arranged in a two-dimensional array form.

[0008] In exemplary embodiments, the first jig includes a first base plate; and a first surface pressure pad provided on a surface of the first base plate facing the second jig, the first base plate including the plurality of first pressure sensing elements; and the second jig includes a second base plate; and a second surface pressure pad provided on a surface of the second base plate facing the first jig, the second base plate including the plurality of second pressure sensing elements.

[0009] In exemplary embodiments, the processor is configured to detect a bending dimension of the battery cell based on a reference thickness of the battery cell and a thickness of the battery cell detected in the inspection jig while the battery cell is pressed with a first load, wherein the reference thickness of the battery cell is a thickness of the battery cell measured while the battery cell is pressed with a second load greater than the first load.

[0010] In exemplary embodiments, the reference thickness of the battery cell is characterized in that the thickness of the battery cell detected in the inspection jig while the battery cell is pressurized with the second load in the inspection jig.

[0011] In exemplary embodiments, the battery cell is further characterized by comprising a thickness measuring device configured to measure the reference thickness of the battery cell.

[0012] In exemplary embodiments, the first load is characterized by being between 1 kgf and 5 kgf.

[0013] In exemplary embodiments, the processor is further configured to detect a final bending dimension of the battery cell based on a difference between a bending dimension of the battery cell and a bending dimension of a normal battery cell.

[0014] In order to solve the above-described problem, the technical idea of ​​the present invention provides an inspection method including the steps of loading a battery cell into an inspection jig including a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements; and the step of detecting a bending dimension and a bending shape of the battery cell based on first pressure data generated from the plurality of first pressure sensing elements, second pressure data generated from the plurality of second pressure sensing elements, and thickness data for a thickness of the battery cell measured while the battery cell is in contact with the first jig and the second jig.

[0015] In exemplary embodiments, the step of detecting the bending dimension of the battery cell includes the step of detecting the bending dimension of the battery cell based on a reference thickness of the battery cell and a thickness of the battery cell detected in the inspection jig while the battery cell is pressed with a first load; wherein the reference thickness of the battery cell is characterized in that the thickness of the battery cell is measured while the battery cell is pressed with a second load greater than the first load.

[0016] In exemplary embodiments, the reference thickness of the battery cell is characterized in that the thickness of the battery cell detected in the inspection jig while the battery cell is pressurized with the second load in the inspection jig.

[0017] In exemplary embodiments, the method further comprises detecting a final bending dimension of the battery cell based on a difference between the bending dimension of the battery cell and the bending dimension of a normal battery cell.

[0018] In exemplary embodiments, the first load is characterized by being between 1 kgf and 5 kgf.

[0019] In exemplary embodiments, the plurality of first pressure sensing elements are arranged in a two-dimensional array form, the plurality of second pressure sensing elements are arranged in a two-dimensional array form, and the plurality of first pressure sensing elements are each aligned with a corresponding one of the plurality of second pressure sensing elements.

[0020] According to the inspection device according to exemplary embodiments, the bending dimension and bending shape of a battery cell can be detected to determine a bending defect of the battery cell, so that the cost required to inspect a bending defect of a battery cell can be reduced.

[0021] According to the inspection device according to exemplary embodiments, data on the bending dimensions and bending shapes of the battery cells for determining bending defects of the battery cells are generated, thereby enabling statistical process management of the bending of the battery cells.

[0022] According to the inspection device according to exemplary embodiments, the inspection reliability for battery cells can be improved through statistical process management for bending of battery cells.

[0023] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0024] Figures 1 to 3 are cross-sectional views showing inspection devices according to exemplary embodiments.

[0025] Figure 4 is a schematic diagram showing an exemplary bending shape of a battery cell.

[0026] FIG. 5 is a schematic diagram schematically showing a first pressure pad and a second pressure pad of an inspection jig according to exemplary embodiments.

[0027] FIG. 6 is a flowchart illustrating an inspection method for inspecting bending of a battery cell according to exemplary embodiments.

[0028] FIG. 7 is a flowchart illustrating a method for detecting a bending dimension of a battery cell in an inspection method for inspecting bending of a battery cell according to exemplary embodiments.

[0029] FIG. 8 is a table for explaining a method for determining a bending dimension as an inspection method of a battery cell according to exemplary embodiments.

[0030] FIG. 9 is a block diagram illustrating an inspection device according to exemplary embodiments.

[0031] Fig. 10 is a cross-sectional view showing a thickness measuring device of an inspection device according to exemplary embodiments.

[0032] In order to solve the above-described problem, the technical idea of ​​the present invention provides an inspection device including: an inspection jig including a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements, and configured to generate thickness data for a thickness of a battery cell provided between the first jig and the second jig while the battery cell is in contact with the first jig and the second jig; and a processor configured to detect a bending dimension and a bending shape of the battery cell based on the first pressure data generated from the plurality of first pressure sensing elements, the second pressure data generated from the plurality of second pressure sensing elements, and the thickness data.

[0033] In order to solve the above-described problem, the technical idea of ​​the present invention provides an inspection method including the steps of loading a battery cell into an inspection jig including a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements; and the step of detecting a bending dimension and a bending shape of the battery cell based on first pressure data generated from the plurality of first pressure sensing elements, second pressure data generated from the plurality of second pressure sensing elements, and thickness data for a thickness of the battery cell measured while the battery cell is in contact with the first jig and the second jig.

[0034] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0035] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0036] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0037] Since the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, the shapes and sizes of components in the drawings may be exaggerated, omitted, or schematically illustrated for clearer explanation. Accordingly, the sizes and proportions of each component do not fully reflect the actual sizes or proportions.

[0038]

[0039] (Example 1)

[0040] Figures 1 to 3 are cross-sectional views showing an inspection device (10) according to exemplary embodiments. Figure 4 is a schematic diagram showing an exemplary bending shape of a battery cell (50).

[0041] Referring to FIGS. 1 to 4, the inspection device (10) can inspect for bending defects in a battery cell (50). Bending of a battery cell (50) may correspond to an appearance defect in a battery cell (50) that has completed an activation process. If bending of a battery cell (50) occurs, the battery cell (50) becomes bent rather than flat. If bending occurs in a battery cell (50), there is a concern that the battery cell (50) may fall from the pick-and-place equipment during the pick-and-place process, which may result in a decrease in yield and safety issues such as a fire outbreak.

[0042] As illustrated in FIG. 4, the bending shape of the battery cell (50) may include a shape in which the center of the battery cell (50) protrudes upward relative to both sides of the battery cell (50), a shape in which the center of the battery cell (50) protrudes downward relative to both sides of the battery cell (50), a shape in which the battery cell (50) is bent to have a wave shape with peaks and valleys, etc.

[0043] The inspection device (10) may include an inspection jig (100) and a control unit (200). In FIGS. 1 to 3, a battery cell (50) having a wave-shaped bending is exemplified as being loaded onto the inspection jig (100).

[0044] The inspection jig (100) may include a first jig (110), a second jig (120), a pressing mechanism (130), and a distance measuring device (140).

[0045] A first jig (110) can support a battery cell (50). The first jig (110) can include a first base plate (111) and a first pressure pad (113). The first pressure pad (113) can be attached to a surface of the first base plate (111) facing the second jig (120). The first pressure pad (113) can include a plurality of first pressure sensing elements (115 in FIG. 5). For example, each of the first pressure sensing elements (115) can include a load cell. The first pressure pad (113) can generate first pressure data including pressure sensing values ​​detected by the plurality of first pressure sensing elements (115).

[0046] In the first pressure pad (113) of the first jig (110), the first pressure sensing elements (115) within the contact areas of the first jig (110) that are in contact with the battery cell (50) can output a pressure sensing value of a certain level or higher, and the remaining first pressure sensing elements (115) within the non-contact areas of the first jig (110) that are not in contact with the battery cell (50) can output a pressure sensing value of lower than the certain level. Based on the first pressure data output from the first pressure pad (113), the contact positions between the first jig (110) and the battery cell (50) can be specified.

[0047] A second jig (120) may be provided on the first jig (110). The second jig (120) may include a second base plate (121) and a second pressure pad (123). The second pressure pad (123) may be attached to a surface of the second base plate (121) facing the first jig (110). The second pressure pad (123) may include a plurality of second pressure sensing elements (125 in FIG. 5). For example, each of the second pressure sensing elements (125) may include a load cell. The second pressure pad (123) may generate second pressure data including pressure sensing values ​​detected by the plurality of second pressure sensing elements (125).

[0048] In the second pressure pad (123) of the second jig (120), the second pressure sensing elements (125) within the contact areas of the second jig (120) that are in contact with the battery cell (50) can output a pressure sensing value above a certain level, and the remaining second pressure sensing elements (125) within the non-contact areas of the second jig (120) that are not in contact with the battery cell (50) can output a pressure sensing value below a certain level. Based on the second pressure data output from the second pressure pad (123), the contact positions between the second jig (120) and the battery cell (50) can be specified.

[0049] In the inspection jig (100), at least one of the first jig (110) and the second jig (120) can be configured to move in a vertical direction (e.g., in the Z-axis direction). By movement of at least one of the first jig (110) and the second jig (120), a distance in the vertical direction (e.g., in the Z-axis direction) between the first jig (110) and the second jig (120) can be adjusted.

[0050] The pressing mechanism (130) may be configured to move at least one of the first jig (110) and the second jig (120) in a vertical direction (e.g., in the Z-axis direction). The pressing mechanism (130) may include an actuator configured to move at least one of the first jig (110) and the second jig (120) in a vertical direction (e.g., in the Z-axis direction). The actuator may include a motor, a hydraulic cylinder, a pneumatic cylinder, or a combination thereof. The pressing mechanism (130) may move at least one of the first jig (110) and the second jig (120) in a vertical direction (e.g., in the Z-axis direction) to pressurize the battery cell (50) provided between the first jig (110) and the second jig (120). For example, the pressing mechanism (130) can move the second jig (120) downward to pressurize the battery cell (50) supported on the first jig (110). The pressing mechanism (130) can control the pressure or load applied to the battery cell (50).

[0051] The distance measuring device (140) may be configured to measure the distance between the first jig (110) and the second jig (120). The distance measuring device (140) may include a distance measuring sensor configured to detect a movement distance of at least one of the first jig (110) and the second jig (120). The distance measuring sensor may include a displacement sensor, a speed sensor, an ultrasonic sensor, an infrared sensor, an encoder, or a combination thereof.

[0052] The inspection jig (100) can generate thickness data for the thickness of the battery cell (50) while the battery cell (50) is in contact with both the first jig (110) and the second jig (120). The thickness data for the thickness of the battery cell (50) can be a value generated by a distance measuring device (140) while the battery cell (50) is in contact with both the first jig (110) and the second jig (120), or a value generated by processing the value generated by the distance measuring device (140).

[0053] The inspection jig (100) can be configured to press the battery cell (50) with a bending inspection load that does not deform the battery cell (50) having the bend into a flat state. When the inspection jig (100) presses the battery cell (50) having the bending with the bending inspection load, the battery cell (50) is brought into contact with both the first jig (110) and the second jig (120), but the battery cell (50) can maintain its bent shape. Since the battery cell (50) maintains its bent shape, the first jig (110) can have a contact area that is in contact with the battery cell (50) and a non-contact area that is not in contact with the battery cell (50), and the second jig (120) can have a contact area that is in contact with the battery cell (50) and a non-contact area that is not in contact with the battery cell (50). When the inspection jig (100) pressurizes the battery cell (50) having bending with a load for bending inspection, the contact position between the first jig (110) and the battery cell (50) can be specified based on the first pressure data output from the first pressure pad (113), and the contact position between the second jig (120) and the battery cell (50) can be specified based on the second pressure data output from the second pressure pad (123).

[0054] When the inspection jig (100) presses the battery cell (50) having the bending with a load for bending inspection, the thickness of the battery cell (50) detected by the inspection jig (100) may be greater than the reference thickness of the battery cell (50). Here, the reference thickness of the battery cell (50) may be defined as the thickness of the battery cell (50) measured while the battery cell (50) is pressed with a load for measuring the reference thickness that is greater than the load for bending inspection. When the battery cell (50) is pressed with the load for measuring the reference thickness, the battery cell (50) becomes generally flat, and the thickness of the battery cell (50) may be generally uniform.

[0055] In exemplary embodiments, the load for bending inspection may be between 1 kgf and 5 kgf. In exemplary embodiments, the load for reference thickness measurement may be between 50 kgf and 200 kgf.

[0056] In exemplary embodiments, the inspection jig (100) may be configured to pressurize the battery cell (50) with a load for measuring a reference thickness and measure the reference thickness of the battery cell (50) pressed with the load for measuring the reference thickness. In other exemplary embodiments, the reference thickness of the battery cell (50) may be measured by another thickness measuring device provided separately from the inspection jig (100).

[0057] The control unit (200) can be connected to the inspection jig (100) in a signal transmission manner and can control the operation of the inspection jig (100). The control unit (200) can include a computing device such as a workstation computer, a desktop computer, a laptop computer, a tablet computer, etc. The control unit (200) can include at least one memory device configured to store data and at least one processor configured to process data. The processor of the control unit (200) can include any one of a simple controller, a microprocessor, a complex processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a processor configured by software, dedicated hardware, and firmware. The processor can be implemented by application-specific hardware such as, for example, a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit).

[0058] The processor of the control unit (200) may be configured to inspect the bending of the battery cell (50) based on the data provided from the inspection jig (100). The processor may be configured to detect the bending dimension and the bending shape of the battery cell (50) based on the data provided from the inspection jig (100). The bending dimension of the battery cell (50) indicates the bending level or bending amount of the battery cell (50). For example, the bending dimension of the battery cell (50) may be the distance along the vertical direction (e.g., the Z-axis direction) between the lowest point and the highest point of one surface of the battery cell (50). For example, the bending dimension of the battery cell (50) may have a value corresponding to the difference between the bending thickness of the battery cell (50) corresponding to the thickness (T1) of the battery cell (50) measured in a state where the battery cell (50) is pressed with a load for bending inspection in the inspection jig (100) and a reference thickness of the battery cell (50).

[0059] The processor of the control unit (200) may be configured to detect the bending dimension and bending shape of the battery cell (50) based on first pressure data output from a plurality of first pressure sensing elements (115), second pressure data output from a plurality of second pressure sensing elements (125), and thickness data for the thickness of the battery cell (50) detected in the inspection jig (100) while the battery cell (50) is in contact with the first jig (110) and the second jig (120). The first pressure data, the second pressure data, and the thickness data used to detect the bending dimension and bending shape of the battery cell (50) may be generated in the inspection jig (100) while the battery cell (50) is pressed with a load for bending inspection in the inspection jig (100).

[0060] FIG. 5 is a schematic diagram schematically showing the first pressure pad (113) and the second pressure pad (123) of the inspection jig (100) according to exemplary embodiments.

[0061] Referring to FIG. 5 together with FIG. 1, in the inspection jig (100), a plurality of first pressure sensing elements (115) of a first pressure pad (113) may be regularly arranged, and a plurality of second pressure sensing elements (125) of a second pressure pad (123) may be regularly arranged. The arrangement of the plurality of first pressure sensing elements (115) provided on the first pressure pad (113) may be substantially the same as the arrangement of the plurality of second pressure sensing elements (125) provided on the second pressure pad (123). In exemplary embodiments, the plurality of first pressure sensing elements (115) may be arranged in a first horizontal direction (e.g., an X-axis direction) and / or a second horizontal direction (e.g., a Y-axis direction), and the plurality of second pressure sensing elements (125) may be arranged in a first horizontal direction (e.g., an X-axis direction) and / or a second horizontal direction (e.g., a Y-axis direction). In exemplary embodiments, a plurality of first pressure sensing elements (115) may be arranged in a two-dimensional array form, and a plurality of second pressure sensing elements (125) may be arranged in a two-dimensional array form.

[0062] Each of the plurality of first pressure sensing elements (115) may be aligned vertically (e.g., in the Z-axis direction) to a corresponding one of the plurality of second pressure sensing elements (125). Each of the individual first pressure sensing elements (115) and each of the individual second pressure sensing elements (125) may be aligned vertically (e.g., in the Z-axis direction) to a corresponding inspection position among the plurality of inspection positions designated for the battery cell (50).

[0063]

[0064] (Example 2)

[0065] FIG. 6 is a flowchart illustrating an inspection method for inspecting bending of a battery cell (50) according to exemplary embodiments. Hereinafter, with reference to FIGS. 1 to 3 together with FIG. 6, an inspection method for inspecting bending of a battery cell (50) using an inspection device (10) will be described.

[0066] Referring to Fig. 1, a battery cell (50) is loaded onto an inspection jig (100) (S110). The battery cell (50) can be placed on the upper surface of a first jig (110) facing a second jig (120).

[0067] Referring to FIG. 2, after loading a battery cell (50) onto an inspection jig (100), the battery cell (50) is pressed with a load for bending inspection, and the bending thickness of the battery cell (50) is detected (S120). The bending thickness of the battery cell (50) may have a value corresponding to the thickness (T1) of the battery cell (50) measured while the battery cell (50) is pressed with a load for bending inspection on the inspection jig (100).

[0068] At step S120, the pressing mechanism (130) can move the second jig (120) downward so that the second jig (120) comes into contact with the battery cell (50), and press the second jig (120) so that the battery cell (50) is pressed with a bending test load between the first jig (110) and the second jig (120). While the battery cell (50) is pressed with the bending test load between the first jig (110) and the second jig (120), the battery cell (50) can remain bent without becoming flat. While the battery cell (50) is pressed between the first jig (110) and the second jig (120) with a load for bending inspection, a part of the bottom surface of the battery cell (50) may contact the first jig (110), and a part of the top surface of the battery cell (50) may contact the second jig (120). Based on the first pressure data output from the first pressure pad (113) and the second pressure data output from the second pressure pad (123), the contact positions between the first jig (110) and the battery cell (50) and the contact positions between the second jig (120) and the battery cell (50) can be confirmed. For example, the first jig (110) and the battery cell (50) can be determined to be in contact with each other at positions corresponding to positions of the first pressure sensing elements (115) that output a pressure sensing value of a certain level or higher, and the second jig (120) and the battery cell (50) can be determined to be in contact with each other at positions corresponding to positions of the second pressure sensing elements (125) that output a pressure sensing value of a certain level or higher.

[0069] Referring to FIG. 3, a battery cell (50) is pressed with a load for measuring a reference thickness, and the reference thickness of the battery cell (50) is detected (S130). The reference thickness of the battery cell (50) may have a value corresponding to the thickness (T2) of the battery cell (50) measured while the battery cell (50) is pressed with a load for measuring a reference thickness in the inspection jig (100).

[0070] In step S130, the pressing mechanism (130) can move the second jig (120) downward so that the second jig (120) comes into contact with the battery cell (50), and press the second jig (120) so that the battery cell (50) is pressed with a load for measuring the reference thickness between the first jig (110) and the second jig (120). The battery cell (50) pressed with the load for measuring the reference thickness can be deformed into a flat state, and the first jig (110) and the second jig (120) can each come into contact with the battery cell (50) at all inspection positions (P1 to P9) of the battery cell (50).

[0071] In exemplary embodiments, step S130 may be performed on a thickness gauge (300 in FIG. 10) provided separately from the inspection jig (100).

[0072] Next, the bending dimension of the battery cell (50) is detected (S140). The bending dimension of the battery cell (50) can be determined based on the bending thickness of the battery cell (50) determined in step S120 and the reference thickness of the battery cell (50) determined in step S130. The value obtained by subtracting the reference thickness of the battery cell (50) determined in step S130 from the bending thickness of the battery cell (50) determined in step S120 can be determined as the bending dimension of the battery cell (50).

[0073] Next, the bending shape of the battery cell (50) is detected (S150). The bending shape of the battery cell (50) can be determined based on first pressure data generated from a plurality of first pressure sensing elements (115), second pressure data generated from a plurality of second pressure sensing elements (125), and the bending dimension of the battery cell (50). The bending shape of the battery cell (50) can be determined through a step of detecting the coordinates of the surface of the battery cell (50) based on the contact positions between the first jig (110) and the battery cell (50) determined while the battery cell (50) is pressed with a load for bending inspection in step S120, the contact positions between the second jig (120) and the battery cell (50) determined while the battery cell (50) is pressed with a load for bending inspection in step S120, and the bending dimension of the battery cell (50) determined in step S140, and a step of modeling the battery cell (50) in a three-dimensional shape based on the detected coordinates of the surface of the battery cell (50). For example, the bending shape of the battery cell (50) may be determined as a shape in which the center of the battery cell (50) protrudes upward relative to both sides of the battery cell (50), a shape in which the center of the battery cell (50) protrudes downward relative to both sides of the battery cell (50), or a shape in which the battery cell (50) is bent to have a wave shape with peaks and valleys.

[0074]

[0075] (Example 3)

[0076] FIG. 7 is a flowchart illustrating a method for detecting a bending dimension of a battery cell (50) in an inspection method for inspecting bending of a battery cell (50) according to exemplary embodiments. Hereinafter, with reference to FIGS. 1 to 3, FIG. 6, and FIG. 7, a method for detecting a bending dimension of a battery cell (50) using an inspection device (10) will be described, and any descriptions that are redundant with those described above will be omitted or simplified.

[0077] Referring to FIG. 7, the first bending dimension of the battery cell (50) is detected based on the bending thickness of the battery cell (50) and the reference thickness of the battery cell (50) (S210). In step S210, the bending thickness of the battery cell (50) can be detected through a step substantially the same as step S120 of FIG. 6, and the reference thickness of the battery cell (50) can be detected through a step substantially the same as step S130 of FIG. 6. A value obtained by subtracting the reference thickness of the battery cell (50) from the bending thickness of the battery cell (50) can be determined as the first bending dimension of the battery cell (50).

[0078] Next, the bending dimension of the normal battery cell is detected (S220). A normal battery cell may refer to a battery cell that is originally flat and has no bending. The bending dimension of the normal battery cell may be determined through a process substantially the same as steps S110, S120, S130, and S140 described with reference to FIG. 6. Step S220 may include a step of loading a normal battery cell onto an inspection jig (100), a step of detecting a bending thickness of the normal battery cell while the normal battery cell loaded onto the inspection jig (100) is pressed with a load for bending inspection, a step of detecting a reference thickness of the normal battery cell while the battery cell (50) is pressed with a load for measuring a reference thickness, and a step of detecting the bending dimension of the normal battery cell. The bending dimension of the normal battery cell may be determined as a value obtained by subtracting the reference thickness of the normal battery cell from the bending thickness of the normal battery cell.

[0079] Next, based on the primary bending dimension of the battery cell (50) and the bending dimension of the normal battery cell, the final bending dimension of the battery cell (50) is detected (S230). Step S230 may be a step of correcting the result value obtained by inspecting the battery cell (50) with bending using the result value obtained from the normal battery cell without bending. Through step S230, errors occurring in equipment such as the inspection jig (100) can be eliminated. The final bending dimension of the battery cell (50) may be determined as a value obtained by subtracting the bending dimension of the normal battery cell determined in step S220 from the primary bending dimension of the battery cell (50) determined in step S210.

[0080] FIG. 8 is a table for explaining an inspection method of a battery cell (50) according to exemplary embodiments. Hereinafter, an exemplary inspection method for a battery cell (50) having a wave-shaped bend will be described with reference to FIGS. 1 to 3 and FIGS. 6 to 8.

[0081] Referring to FIG. 2, after pressurizing the battery cell (50) with a load for bending inspection, first pressure data and second pressure data are generated. Contact positions between the first jig (110) and the battery cell (50) can be detected based on pressure sensing values ​​sensed by a plurality of first pressure sensing elements (115) arranged at a plurality of inspection positions (P1 to P9), and contact positions between the second jig (120) and the battery cell (50) can be detected based on pressure sensing values ​​sensed by a plurality of second pressure sensing elements (125) arranged at a plurality of inspection positions (P1 to P9).

[0082] In the table of FIG. 8, the first pressure data is simply illustrated as “O” or “X” depending on whether there is contact between the first jig (110) and the battery cell (50), but the first pressure data may include pressure sensing values ​​output from a plurality of first pressure sensing elements (115). Similarly, the second pressure data is simply illustrated as “O” or “X” depending on whether there is contact between the second jig (120) and the battery cell (50), but the second pressure data may include pressure sensing values ​​output from a plurality of first pressure sensing elements (125). For example, if the pressure sensing value output from the first pressure sensing element (115) is greater than a certain value, it is determined that contact between the first jig (110) and the battery cell (50) has occurred, and is indicated as "O". If the pressure sensing value output from the first pressure sensing element (115) is less than a certain value, it is determined that contact between the first jig (110) and the battery cell (50) has not occurred, and is indicated as "X". Similarly, if the pressure sensing value output from the second pressure sensing element (125) is greater than a certain value, it is determined that contact between the second jig (120) and the battery cell (50) has occurred, and is indicated as "O". If the pressure sensing value output from the second pressure sensing element (125) is less than a certain value, it is determined that contact between the second jig (120) and the battery cell (50) has not occurred, and is indicated as "X".

[0083] Next, the bending thickness of the battery cell (50) is detected while the battery cell (50) is pressed with a load for bending inspection. The bending thickness of the battery cell (50) may have a value corresponding to the thickness (T1) of the battery cell (50) measured in the inspection jig (100) while the battery cell (50) is pressed with a load for bending inspection, and may be assigned to contact locations (P3, P9) between the second jig (120) and the battery cell (50).

[0084] Referring to FIG. 3, after detecting the bending thickness of the battery cell (50) while the battery cell (50) is pressed with a load for bending inspection, the reference thickness of the battery cell (50) is detected while the battery cell (50) is pressed with a load for reference thickness measurement. The battery cell (50) pressed with the load for reference thickness measurement can be deformed flat to have a uniform thickness. The reference thickness of the battery cell (50) may be the thickness (T2) of the battery cell (50) measured in the inspection jig (100) while the battery cell (50) is pressed with the load for reference thickness measurement. Alternatively, the reference thickness of the battery cell (50) may be the thickness of the battery cell (50) measured in a thickness measuring device (300 of FIG. 10) provided separately from the inspection jig (100).

[0085] Next, the first bending dimension of the battery cell (50) is determined based on the bending thickness of the battery cell (50) and the reference thickness of the battery cell (50). The first bending dimension of the battery cell (50) can be determined as a value obtained by subtracting the reference thickness of the battery cell (50) from the bending thickness of the battery cell (50). For example, the first bending dimension of the battery cell (50) can be assigned to contact positions (P3, P9) between the second jig (120) and the battery cell (50) while the battery cell (50) is pressed with a load for bending inspection, and the first bending dimension of the battery cell (50) can be determined as 3 mm, which is a value obtained by subtracting 13 mm corresponding to the bending thickness of the battery cell (50) and 10 mm corresponding to the reference thickness of the battery cell (50).

[0086] Next, the final bending dimension of the battery cell (50) is determined based on the primary bending dimension of the battery cell (50) and the bending dimension of the normal battery cell. The final bending dimension of the battery cell (50) can be determined as a value obtained by subtracting the bending dimension of the normal battery cell from the primary bending dimension of the battery cell (50). For example, the final bending dimension of the battery cell (50) can be determined as 2.5 mm, which corresponds to 0.5 mm, which corresponds to the bending dimension of the normal battery cell, from 3 mm, which corresponds to the primary bending dimension of the battery cell (50).

[0087] Next, the bending shape of the battery cell (50) is detected. Detecting the bending shape of the battery cell (50) may include modeling the shape of the battery cell (50) in a three-dimensional or three-dimensional form. The bending shape of the battery cell (50) may be determined based on the contact positions between the first jig (110) and the battery cell (50) determined while the battery cell (50) is pressed with a load for bending inspection, the contact positions between the second jig (120) and the battery cell (50) determined while the battery cell (50) is pressed with a load for bending inspection, and the final bending dimension of the battery cell (50).

[0088] For example, the spatial coordinates of one surface of the battery cell (50) at contact locations (P1, P7) between the first jig (110) and the battery cell (50) detected while the battery cell (50) is pressed with a load for bending inspection may have a Z-axis value corresponding to the reference thickness of the battery cell (50), and the spatial coordinates of one surface of the battery cell (50) at contact locations (P3, P9) between the second jig (120) and the battery cell (50) detected while the battery cell (50) is pressed with a load for bending inspection may have a Z-axis value corresponding to the final bending dimension of the battery cell (50). Based on the spatial coordinates of the battery cell (50) acquired at contact locations (P1, P7) between the first jig (110) and the battery cell (50) detected while the battery cell (50) is pressed with a load for bending inspection, and the spatial coordinates of the battery cell (50) acquired at contact locations (P3, P9) between the second jig (120) and the battery cell (50) detected while the battery cell (50) is pressed with a load for bending inspection, one surface of the battery cell (50) can be modeled in a three-dimensional form.

[0089] Next, based on the bending dimension and bending shape of the battery cell (50), it is possible to determine whether the battery cell (50) has a bending defect. For example, if the bending dimension of the battery cell (50) is within the normal dimension, the battery cell (50) can be determined to be normal, and if the bending dimension of the battery cell (50) exceeds the normal dimension, the battery cell (50) can be determined to be defective. The normal dimension of the battery cell (50) can be determined according to the bending shape of the battery cell (50). For example, the normal dimension of a battery cell (50) having a wave-shaped bending can be determined to be 2 mm. In this case, if the final bending dimension of the battery cell (50) is detected to be 2.5 mm, the battery cell (50) can be determined to have a bending defect.

[0090]

[0091] (Example 4)

[0092] Fig. 9 is a block diagram illustrating an inspection device (10A) according to exemplary embodiments. Fig. 10 is a cross-sectional view illustrating a thickness measuring device (300) of the inspection device (10A) according to exemplary embodiments. Hereinafter, the inspection device (10A) of Figs. 9 and 10 will be described, focusing on differences from the inspection device (10A) described with reference to Figs. 1 to 3.

[0093] Referring to FIGS. 9 and 10, the inspection device (10A) may further include a thickness measuring device (300). The thickness measuring device (300) may include a first jig (310), a second jig (320), a pressing mechanism (330), and a distance measuring device (340). The thickness measuring device (300) may be substantially the same as or similar to the inspection jig (100), except that the first pressure pad (113) is not provided on the first jig (310) and the second pressure pad (123) is not provided on the second jig (320).

[0094] The first jig (310) can support the battery cell (50), and the second jig (320) can be provided on the battery cell (50). At least one of the first jig (310) and the second jig (320) can be configured to move in a vertical direction (e.g., in the Z-axis direction). The pressing mechanism (330) can press the battery cell (50) provided between the first jig (310) and the second jig (320) by moving at least one of the first jig (310) and the second jig (320) in a vertical direction (e.g., in the Z-axis direction). The pressing mechanism (330) can adjust the pressure or load applied to the battery cell (50). The distance measuring device (340) can be configured to measure the distance between the first jig (310) and the second jig (320). The thickness measuring device (300) can generate thickness data on the thickness of the battery cell (50) while the battery cell (50) is in contact with both the first jig (310) and the second jig (320). The thickness data on the thickness of the battery cell (50) can be a value generated by the distance measuring device (340) while the battery cell (50) is in contact with both the first jig (310) and the second jig (320), or a value generated by processing the value generated by the distance measuring device (340).

[0095] The thickness gauge (300) may be configured to detect the reference thickness of the battery cell (50) while the battery cell (50) is pressed with a load for measuring the reference thickness, and may be configured to provide the reference thickness of the battery cell (50) to the inspection jig (100). The inspection jig (100) may be configured to detect the bending dimension of the battery cell (50) based on the reference thickness of the battery cell (50) provided by the thickness gauge (300).

[0096] Typically, bending defects in battery cells are detected through visual inspection or manual work by workers.

[0097] According to the inspection device according to exemplary embodiments, the bending dimension and bending shape of a battery cell can be detected to determine a bending defect of the battery cell, so that the cost required to inspect a bending defect of a battery cell can be reduced.

[0098] According to the inspection device according to exemplary embodiments, data on the bending dimensions and bending shapes of the battery cells for determining bending defects of the battery cells are generated, thereby enabling statistical process management of the bending of the battery cells.

[0099] According to the inspection device according to exemplary embodiments, the inspection reliability for battery cells can be improved through statistical process management for bending of battery cells.

[0100] The present invention has been described in more detail through drawings and examples. However, the configurations described in the drawings or examples described in this specification are merely embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

Claims

1. An inspection jig comprising a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements, and configured to generate thickness data for the thickness of a battery cell provided between the first jig and the second jig while the battery cell is in contact with the first jig and the second jig; and A processor configured to detect a bending dimension and a bending shape of the battery cell based on first pressure data generated from the plurality of first pressure sensing elements, second pressure data generated from the plurality of second pressure sensing elements, and the thickness data; Inspection device including.

2. In paragraph 1, An inspection device, characterized in that each of the plurality of first pressure sensing elements is aligned with a corresponding one of the plurality of second pressure sensing elements.

3. In paragraph 2, The above plurality of first pressure sensing elements are arranged in a two-dimensional array form, An inspection device characterized in that the plurality of second pressure sensing elements are arranged in a two-dimensional array form.

4. In paragraph 1, The above first jig, first base plate; and A first pressure pad including the plurality of first pressure sensing elements and provided on a surface of the first base plate facing the second jig; Including, The above second jig, a second base plate; and A second pressure pad including the plurality of second pressure sensing elements and provided on the surface of the second base plate facing the first jig; An inspection device characterized by including:

5. In paragraph 1, The processor is configured to detect the bending dimension of the battery cell based on the reference thickness of the battery cell and the thickness of the battery cell detected by the inspection jig while the battery cell is pressed with a first load, An inspection device characterized in that the reference thickness of the battery cell is a thickness of the battery cell measured while the battery cell is pressurized with a second load greater than the first load.

6. In paragraph 5, An inspection device characterized in that the reference thickness of the battery cell is the thickness of the battery cell detected in the inspection jig while the battery cell is pressurized by the second load in the inspection jig.

7. In paragraph 5, An inspection device characterized in that it further comprises a thickness measuring device configured to measure the reference thickness of the battery cell.

8. In paragraph 5, An inspection device characterized in that the first load is between 1 kgf and 5 kgf.

9. In paragraph 5, An inspection device characterized in that the processor is further configured to detect the final bending dimension of the battery cell based on the difference between the bending dimension of the battery cell and the bending dimension of a normal battery cell.

10. A step of loading a battery cell into an inspection jig including a first jig having a plurality of first pressure sensing elements and a second jig having a plurality of second pressure sensing elements; and A step of detecting a bending dimension and a bending shape of the battery cell based on first pressure data generated from the plurality of first pressure sensing elements, second pressure data generated from the plurality of second pressure sensing elements, and thickness data for the thickness of the battery cell measured while the battery cell is in contact with the first jig and the second jig; A method of inspection including:

11. In paragraph 10, The step of detecting the bending dimension of the above battery cell is: A step of detecting a bending dimension of the battery cell based on a reference thickness of the battery cell and a thickness of the battery cell detected by the inspection jig while the battery cell is pressurized with a first load; Including, An inspection method characterized in that the reference thickness of the battery cell is a thickness of the battery cell measured while the battery cell is pressurized with a second load greater than the first load.

12. In paragraph 11, An inspection method characterized in that the reference thickness of the battery cell is the thickness of the battery cell detected in the inspection jig while the battery cell is pressurized with the second load in the inspection jig.

13. In paragraph 11, An inspection method characterized in that it further includes a step of detecting the final bending dimension of the battery cell based on the difference between the bending dimension of the battery cell and the bending dimension of a normal battery cell.

14. In paragraph 11, An inspection method characterized in that the first load is between 1 kgf and 5 kgf.

15. In paragraph 10, The above plurality of first pressure sensing elements are arranged in a two-dimensional array form, The above plurality of second pressure sensing elements are arranged in a two-dimensional array form, An inspection method, characterized in that each of the plurality of first pressure sensing elements is aligned with a corresponding one of the plurality of second pressure sensing elements.

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