Battery cell outer material folding portion defect detection device

Abstract

According to an embodiment of the present invention, a battery cell outer casing material fold defect detection device may include: a magnetic field outputter that outputs a magnetic field to the fold of the battery cell outer casing material; a characteristic measuring device that measures the characteristics of the fold based on the magnetic field; and a controller that generates defect information of the fold based on the measurement results of the characteristic measuring device.

Description

Technical Field

[0001] This utility model relates to a device for detecting defects in the folding part of the battery cell outer casing material. Background Technology

[0002] Unlike primary batteries, secondary batteries can be charged and discharged, offering convenience and thus attracting attention as power sources for various mobile devices and electric vehicles. Such secondary batteries can include cells, in which electrode assemblies formed by stacking or rolling positive and negative plates and separators are housed within a casing. Multiple cells can be stacked along a predetermined direction and included in a battery module, battery pack, or battery rack. A battery pack or rack can include multiple battery modules.

[0003] If the safety of any single cell among multiple cells included in a battery module, battery pack, or battery rack cannot be ensured, the safety of the entire set of cells may not be guaranteed. Therefore, cell safety is crucial, and extensive research is underway into technologies for detecting cell defects. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] The folds in the outer casing material of the battery cell may have folded structures, and these folds can generate stress within the folds. Therefore, the likelihood of defects occurring in the folds of the outer casing material may be higher than that of defects occurring in the rest of the outer casing material. Defects in the folds may reduce the sealing performance of the outer casing material to the electrode assembly, and reduced sealing performance of the electrode assembly may lead to decreased battery cell safety. Therefore, detecting defects in the folds is important.

[0006] The present invention aims to provide a device for detecting defects in the folds of battery cell outer materials, such as cracks, which can efficiently detect defects in the folds of the outer materials of battery cells.

[0007] (II) Technical Solution

[0008] According to an embodiment of the present invention, a battery cell outer casing material fold defect detection device may include: a magnetic field outputter that outputs a magnetic field to the fold of the battery cell outer casing material; a characteristic measuring device that measures the characteristics of the fold based on the magnetic field; and a controller that generates defect information of the fold based on the measurement results of the characteristic measuring device.

[0009] For example, the characteristics based on the magnetic field may include the surface resistance of the fold, and the characteristic measuring device can measure the surface resistance of the fold.

[0010] For example, the magnetic field output device can output a magnetic field to multiple coordinates of the folded portion based on the movement of one of the magnetic field output device and the battery cell, and the controller can generate defect information of the folded portion based on whether there are coordinates with surface resistance greater than a reference value among the multiple coordinates.

[0011] For example, the battery cell can be disposed between the magnetic field output device and the characteristic measuring device, the characteristic measuring device can have one side, and the battery cell is disposed on that side.

[0012] For example, the characteristics based on the magnetic field may include the eddy current characteristics of the fold based on the magnetic field, and the characteristic measuring device may include a pickup coil having an inductance for measuring the eddy current characteristics of the fold based on the magnetic field.

[0013] For example, the characteristic measuring device may further include a measuring circuit that measures the resonant frequency of the LC resonance based on the inductance of the pickup coil.

[0014] For example, the magnetic field outputter can output a magnetic field to multiple coordinates of the folded portion based on the movement of either the magnetic field outputter or the battery cell.

[0015] For example, the folded portion may be located at one edge of the outer material, and the magnetic field outputter may output a magnetic field to multiple coordinates of the folded portion based on one-dimensional movement of the magnetic field outputter and one of the battery cells.

[0016] For example, the outer material may include an embedded metal layer, and the defect information of the fold may include crack detection information of the metal layer.

[0017] (III) Beneficial Effects

[0018] According to an embodiment of the present invention, a battery cell outer casing material folding defect detection device can efficiently detect folding defects without unfolding or disassembling the folding part, and without using large-scale, high-cost, or time-consuming detection equipment (e.g., equipment using X-rays or polarized light). Attached Figure Description

[0019] Figure 1 and Figure 2 The figures are respectively illustrations of a battery cell casing material folding defect detection device according to an embodiment of the present invention.

[0020] Figure 3 This is a diagram illustrating a battery cell casing material folding defect detection device and method according to an embodiment of the present invention, which generates eddy currents by outputting a magnetic field.

[0021] Figure 4 This is a graph illustrating the surface resistance measurement results of each coordinate of the folded portion of the battery cell casing material according to an embodiment of the present invention.

[0022] Figure 5 This is a circuit diagram illustrating the circuit structure of the magnetic field output device of a battery cell outer casing material folding defect detection device according to an embodiment of the present invention.

[0023] Figure 6 This is a flowchart illustrating a method for detecting defects in the folded portion of the battery cell casing material according to an embodiment of the present invention.

[0024] Figure 7 This is a flowchart illustrating a device and method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention, based on surface resistance measurement results at each coordinate of the folded portion, to detect cracks in the folded portion.

[0025] Figure 8 This is a flowchart illustrating a device and method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention, which detects cracks in the folded portion based on the inductance measurement results of each coordinate of the folded portion.

[0026] Explanation of reference numerals in the attached figures:

[0027] 110: Battery Cell

[0028] 112: Exterior materials

[0029] 113: Electrode assembly

[0030] 114: Electrode leads

[0031] 115: Folding portion

[0032] 117: Terrace Section

[0033] 117a: Joint

[0034] 118: Adhesive components

[0035] 210: Magnetic field output device

[0036] 220, 220a, 220b: Characteristic measuring instruments

[0037] 230: Controller Detailed Implementation

[0038] Before detailing the embodiments, the terms or words used in the following description and claims should not be construed as having their usual or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical idea of ​​this utility model, based on the principle that the inventor can appropriately define the concepts of terms to best illustrate his utility model.

[0039] The same reference numerals or symbols used in the various figures indicate parts or components that perform substantially the same function. For ease of explanation and understanding, the same reference numerals or symbols may also be used in different embodiments.

[0040] In the following description, unless the context clearly indicates otherwise, singular expressions include plural expressions. Terms such as “comprising” or “constituting” are used to specify the presence of features, numbers, steps, operations, components, parts or combinations thereof described in the specification, but should not be construed as excluding the presence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

[0041] Furthermore, in the following description, terms such as "upper side," "upper part," "lower side," "lower part," "side," "front," and "rear" are based on the direction shown in the attached drawings. When the direction of the corresponding object changes, it can be described in different ways.

[0042] Furthermore, in the following description and claims, terms including ordinal numbers such as "first," "second," etc., may be used to distinguish components. These ordinal numbers are used to distinguish identical or similar components, and the meaning of the terms should not be interpreted limitingly by the use of these ordinal numbers. For example, the components associated with these ordinal numbers should not be interpreted limitingly by their numbers, such as the order of use or the order of arrangement. The ordinal numbers may be used interchangeably as needed.

[0043] Figure 1 and Figure 2 These figures illustrate a device for detecting defects in the folding portion of a battery cell casing material according to an embodiment of the present invention. (Refer to...) Figure 1 and Figure 2 According to one embodiment of the present invention, a battery cell outer material folding defect detection device may include a magnetic field output device 210, characteristic measuring devices 220a and 220b and a controller 230, and can detect defects in the folding portion 115 of the outer material 112 of the battery cell 110 (e.g., cracks in the metal layer 115a).

[0044] The battery cell 110 may include at least one of the following: outer casing material 112, electrode assembly 113, electrode leads 114, fold 115, terrace portion 117, joint portion 117a, and adhesive component 118. For example, a battery module may include multiple battery cells 110, and a battery pack or rack may include multiple battery modules. The following description will focus on a pouch-type battery cell 110, but the type of battery cell 110 (e.g., cylindrical, prismatic) is not limited to pouch type, and the specific shape of the pouch-type battery cell 110 may vary depending on the design.

[0045] The battery cell 110 may have a structure in which a positive electrode plate, a negative electrode plate, a separator, and an electrolyte are disposed inside the outer casing material 112. The electrode assembly 113 may have a structure in which multiple positive electrode plate portions and multiple negative electrode plate portions are stacked alternately, and the separator may be sandwiched between the positive and negative electrode plates. The outer casing material 112 may accommodate the electrode assembly 113 by three-dimensionally wrapping the electrode assembly 113.

[0046] Electrode leads 114 provide an electrical connection path between the interior and exterior of the cell 110. A portion of the electrode lead 114 may be exposed outside the outer casing material 112 and may protrude in the Y direction. Multiple portions of the electrode lead 114 may be connected to the positive and negative plates of the electrode assembly 113, respectively, and may protrude in the +Y and -Y directions, respectively, or may protrude only in one of the +Y and -Y directions. The multiple positive and negative plate portions of the electrode assembly 113 may each have electrode tabs for connection to the electrode lead 114, and may be coupled to each other and to the electrode lead 114 at a junction 117a.

[0047] The terrace portion 117 may represent the remaining space in the outer casing 112 excluding the electrode assembly 113, and may be an edge portion of the outer casing 112. The terrace portion 117 may include: a joining portion 117a corresponding to the edge of the outer casing 112 in the Y direction; and a fold portion 115 corresponding to the edge of the outer casing 112 in the +Z direction. The terrace portion 117 may seal the electrode assembly 113 housed within the outer casing 112. For example, the area in the terrace portion 117 other than the fold portion 115 may be an area formed by sealing through methods such as heat welding.

[0048] The fold 115 may be located at one edge of the outer material 112. The fold 115 may be a region formed by folding one side of the outer material 112. With the electrode assembly 113 placed on the outer material 112, the fold 115 may be formed by folding one side of the outer material 112, and with the two ends of the outer material 112 facing each other, a terrace portion 117 may be formed by sealing the remaining area of ​​the outer material 112 other than the fold 115.

[0049] For example, the folding portion 115 can be folded 180° along the first fold line C1 and then folded along the second fold line C2, and the adhesive component 118 can adhesively bond multiple parts of the folding portion 115 to fix the folding structure of the folding portion 115. Through the folding structure of the folding portion 115, the outer material 112 can minimize its volume while sealing the electrode assembly 113.

[0050] However, the folding of the fold 115 may generate stress within the fold 115. Therefore, the probability of defects occurring in the fold 115 of the outer casing material 112 may be higher than that of defects occurring in the rest of the outer casing material 112. Defects in the fold 115 may reduce the sealing performance of the outer casing material 112 to the electrode assembly 113; therefore, it is important to detect defects in the fold 115.

[0051] For example, the outer material 112 including the fold 115 may include an embedded metal layer 115a, and may further include a first insulating layer 115p and a second insulating layer 115s. The first and second insulating layers 115p and 115s may each be made of plastics such as nylon, polyethylene terephthalate (PET), and polypropylene (PP), but are not limited to these. The metal layer 115a may be disposed between the first insulating layer 115p and the second insulating layer 115s to maintain the shape of the outer material 112. When a specific portion A of the metal layer 115a is in a normal state (A-1), the metal layer 115a can prevent the penetration of foreign matter (e.g., moisture). When a crack (A-2) appears in the specific portion A of the metal layer 115a, foreign matter (e.g., moisture) can penetrate into the electrode assembly 113 through the crack (A-2) in the metal layer 115a. Moisture penetrating the electrode assembly 113 may form a complex (e.g., lithium oxide) between the electrolyte components (e.g., lithium) and the metal layer 115a components (e.g., aluminum), or cause corrosion of the electrode assembly 113. As the complex (e.g., lithium oxide) gradually grows or corrosion progresses, the cell 110 may gradually expand. The expansion of the cell 110 may reduce its safety.

[0052] The magnetic field output device 210 can output a magnetic field to the fold 115 of the outer casing material 112 of the battery cell 110. Characteristic measuring devices 220a and 220b can measure the characteristics of the fold 115 based on the magnetic field. The controller 230 can generate defect information of the fold 115 based on the measurement results of the characteristic measuring devices 220a and 220b. Therefore, the battery cell outer casing material fold defect detection device according to an embodiment of the present invention can efficiently detect defects in the fold 115 without unfolding or disassembling the fold 115, and without using large-scale, high-cost, or time-consuming detection equipment (e.g., equipment using X-rays or polarized light).

[0053] Figure 3 This diagram illustrates a device and method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention, which generates eddy currents through an output magnetic field. (Refer to...) Figure 1 and Figure 3 The magnetic field output by the magnetic field outputter 210 (Primary Field) can pass through the metal layer 115a of the fold 115, and changes in the magnetic field (e.g., changes in the AC signal value) can generate eddy currents in the metal layer 115a. These eddy currents can form a secondary magnetic field, and the characteristic measuring device 220 can measure the eddy currents by measuring the secondary magnetic field.

[0054] Cracks in the metal layer 115a of the fold 115 may hinder the formation of eddy currents, thus reducing eddy currents. That is, the surface resistance at the coordinates of the crack location in the metal layer 115a may increase. The characteristics of the fold 115 based on the primary field can include the surface resistance of the fold 115, which can be measured by the characteristic measuring device 220. For example, the magnitude of the current (or the amplitude of the alternating current) flowing through the characteristic measuring device 220 via the secondary field can be determined based on the eddy currents of the fold 115. Therefore, the characteristic measuring device 220 can measure the eddy currents of the fold 115 and the surface resistance of the fold 115 by measuring the magnitude of the current (or the amplitude of the alternating current) flowing through the characteristic measuring device 220.

[0055] For example, the battery cell 110 can be disposed between the magnetic field output device 210 and the characteristic measuring device 220a, the characteristic measuring device 220a may have one side, on which the battery cell 110 is disposed. The characteristic measuring device 220a may be a surface resistance measuring device, but is not limited to this. For example, at least one [missing information] may be disposed inside the characteristic measuring device 220a. Figure 2 The characteristic measuring device 220a includes a fixed assembly of a pickup coil 221 and a measuring circuit 222, and may include a housing surrounding the fixed assembly. The battery cell 110 may be in direct contact with the housing of the characteristic measuring device 220a, and at least a portion of the housing may include an insulating layer to allow magnetic fields to pass through, and other portions of the housing may include terminals for electrical connection to or communication with the controller 230.

[0056] Figure 4 This is a graph illustrating the surface resistivity measurement results of various coordinates of the folded portion of a battery cell casing material folding defect detection device and method according to an embodiment of the present invention. (Refer to...) Figure 1 and Figure 4 The magnetic field output device 210 can output magnetic fields to multiple coordinates of the folded portion 115 based on the movement of either the magnetic field output device 210 or the battery cell 110. The controller 230 can generate defect information of the folded portion 115 based on whether there are coordinates among the multiple coordinates where the surface resistance is greater than a reference value (detection reference). The defect information of the folded portion 115 may include crack detection information of the metal layer 115a. For example, the reference value (detection reference) can be pre-stored in the controller 230 and can be changed according to the model of the battery cell 110 or the environment (e.g., temperature).

[0057] The controller 230 can control the movement of one of the magnetic field output device 210 and the battery cell 110. For example, the controller 230 can control the movement of the magnetic field output device 210 by sending a movement control signal to an actuator that moves the induction coil 211 of the magnetic field output device 210 in the Y direction. For example, the actuator can be a linear actuator that achieves linear motion of the induction coil 211. For example, the controller 230 can pre-store movement path information and generate the movement control signal based on the movement path information to prevent the induction coil 211 from deviating from the movement path. By design, the moving induction coil 211 can be replaced by multiple induction coils 211 arranged along the Y direction.

[0058] Figure 4 The fold section is shown. Figure 1A crack occurred at a specific coordinate (115), causing the surface resistance at that coordinate to exceed the surface resistance curve of the detection reference. Therefore, the controller ( Figure 1 (230) can generate crack detection information for folded sections. If the folded section ( Figure 1 If no cracks occur in (115), then none of the coordinates of the surface resistance curve will exceed the detection reference, and the controller ( Figure 1 (230) can generate information on undetected cracks in the folded section. Controller ( Figure 1 230) can be like Figure 4 The diagram shows the folds ( Figure 1 The surface resistance distribution at multiple coordinates (115) is mapped and used as fold defect information to generate mapping information.

[0059] The fold 115 can be located only at one edge of the outer casing 112. Therefore, the magnetic field outputter 210 can output magnetic fields to multiple coordinates of the fold 115 based on one-dimensional movement (e.g., movement only in the Y direction) of either the magnetic field outputter 210 or the battery cell 110. Thus, the movement path of either the magnetic field outputter 210 or the battery cell 110 can be shortened, thereby reducing the time required for the battery cell outer casing fold defect detection device and method to detect defects in each battery cell 110. The fold 115 does not overlap with the electrode leads 114 and the electrode assembly 113 in the X direction; therefore, the movement path of the magnetic field outputter 210 can also be non-overlapping with the electrode leads 114 and the electrode assembly 113 in the X direction. For example, the controller 230 can, based on the movement path information set to one-dimensional movement only, cause the induction coil 211 of the magnetic field outputter 210 to move only in the Y direction.

[0060] Figure 5 This is a circuit diagram illustrating the circuit structure of the magnetic field output device of a battery cell casing material folding defect detection device according to an embodiment of the present invention. (Refer to...) Figure 1 and Figure 5 The magnetic field output device 210 may include an induction coil 211 and an induced current generator 212. The induced current generator 212 may include an AC power supply 213, a transformer 214, and multiple capacitors 215 and 216. The AC power supply 213 can provide an AC voltage with a specific frequency. At least one of the multiple capacitors 215 and 216 can generate LC resonance with the induction coil 211. The transformer 214 can be connected between the AC power supply 213 and the induction coil 211 to prevent the LC resonance from adversely affecting the AC voltage provided by the AC power supply 213. An AC current with a specific frequency can flow through the induction coil 211 and can correspond to the magnetic field of the induction coil 211.

[0061] Refer again Figure 2 and Figure 3 The characteristics of the folded portion 115 based on the primary field may include the eddy current characteristics of the folded portion 115 based on the primary field. The characteristic measuring device 220b may include a pickup coil 221 having an inductance for measuring the eddy current characteristics of the folded portion 115 based on the primary field. The inductance of the pickup coil 221 may be determined by a combination of self-inductance and mutual inductance, and the mutual inductance of the pickup coil 221 may change due to the eddy currents of the folded portion 115. Therefore, the measurement circuit 222 of the characteristic measuring device 220b can measure the eddy currents of the folded portion 115 by measuring the inductance of the pickup coil 221, and can also measure the surface resistance of the folded portion 115. The controller 230 can detect defects in the folded portion 115 based on the inductance of the pickup coil 221.

[0062] For example, when the controller 230 moves the induction coil 211 of the magnetic field output device 210, the pickup coil 221 can also be moved together. Therefore, the induction coil 211 and the pickup coil 221 can always overlap in the X direction. The induction coil 211 and the pickup coil 221 can be implemented substantially identically (e.g., with the same number of turns and the same coil diameter), but are not limited to this. Depending on the design, the movable pickup coil 221 can be replaced by multiple pickup coils 221 arranged along the Y direction, and... Figure 1 The characteristic measuring device 220a may also contain multiple pickup coils 221 arranged along the Y direction.

[0063] The characteristic measuring device 220b may further include a measuring circuit 222 that measures the resonant frequency of the LC resonance based on the inductance of the pickup coil 221. The resonant frequency of the LC resonance can be determined by the combination of the inductance of the pickup coil 221 and the capacitance of the capacitor within the measuring circuit 222; therefore, the resonant frequency of the LC resonance can correspond to the inductance of the pickup coil 221 (which depends on the eddy currents in the fold 115). Thus, the controller 230 can detect defects in the fold 115 based on the resonant frequency of the LC resonance based on the inductance of the pickup coil 221.

[0064] For example, the measurement circuit 222 can generate a sampling signal having a resonant frequency based on the inductance of the pickup coil 221 when the fold 115 is normal, and can measure the amplitude of the sampling signal. When the amplitude of the sampling signal changes significantly, the controller 230 can generate information indicating that the fold 115 has a defect.

[0065] For example, at least a portion of controller 230 can be implemented as a computing system (including a processor, memory, storage device, input / output device, and communication device), similar to a microcontroller. For example, at least a portion of controller 230 can be implemented as a programmable logic controller or an embedded system to perform only predefined operations. For example, controller 230 can send generated information to a process control system such as a manufacturing execution system (MES), output to a user (e.g., display), or remotely send it to a user's terminal device. Depending on the design, other parts of controller 230 and / or measurement circuitry 222 can be implemented as a digital multimeter, or include analog measurement circuitry (e.g., sampling circuitry, buffer circuitry, amplification circuitry, analog-to-digital conversion circuitry).

[0066] Figure 6 This is a flowchart illustrating a method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention. (Refer to...) Figure 1 and Figure 6 A method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention may include: a step (S110) where a battery cell casing material folded portion defect detection device outputs a magnetic field to the folded portion 115 of the casing material 112 of the battery cell 110; a step (S120) where the characteristics of the folded portion 115 based on the magnetic field are measured; and a step (S130) where defect information of the folded portion 115 is generated based on the characteristics of the magnetic field. Therefore, the method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention can efficiently detect defects in the folded portion 115 without unfolding or disassembling the folded portion 115, and without using large-scale, high-cost, or time-consuming detection equipment (e.g., equipment using X-rays or polarized light).

[0067] Figure 7 This is a flowchart illustrating a device and method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention, based on surface resistance measurement results at various coordinates of the folded portion, to detect cracks in the folded portion. Figure 8 This is a flowchart illustrating a device and method for detecting defects in the folded portion of a battery cell casing material according to an embodiment of the present invention, which detects cracks in the folded portion based on the inductance measurement results of each coordinate of the folded portion.

[0068] Reference Figure 1 , Figure 7 and Figure 8The output steps of the method for detecting defects in the folded portion of the battery cell outer casing material according to an embodiment of the present invention ( Figure 6 S110 may include: the magnetic field output device 210 continuously scans multiple coordinates of the fold 115 of the cell 110 (S111). The scanning may mean outputting a magnetic field to multiple coordinates of the fold 115 based on a one-dimensional movement (e.g., movement only in the Y direction) of one of the magnetic field output device 210 and the cell 110.

[0069] Reference Figure 1 and Figure 7 The measurement steps of the method for detecting defects in the folded portion of the battery cell outer casing material according to an embodiment of the present invention ( Figure 6 S120 may include: a characteristic measuring instrument 220a measuring the surface resistance at each coordinate of the fold 115 (S121). That is, the measurement step ( Figure 6 The magnetic field-based properties of S120 may include the surface resistance of the fold 115.

[0070] The generation steps of the method for detecting defects in the folded portion of the battery cell outer casing material according to an embodiment of the present invention ( Figure 6 S130 may include: the controller 230 generating defect (e.g., crack) information for the fold 115 based on whether there are coordinates with surface resistance greater than a reference value among multiple coordinates (S131), and excluding the cell with detected crack in the fold from the battery module (including multiple cells) (S145). If the fold 115 does not have a crack, the surface resistance of the multiple coordinates of the fold 115 will not exceed the reference value, so the controller 230 can generate fold crack undetected information (S134), and can stack multiple cells including the cell to assemble the battery module (S144).

[0071] Reference Figure 2 and Figure 8 The measurement steps of the method for detecting defects in the folded portion of the battery cell outer casing material according to an embodiment of the present invention ( Figure 6 S120 may include: a characteristic measuring device 220b measuring the inductance of a pickup coil 221 having an inductance for measuring the eddy current characteristics of the folded portion 115 (S122), and may further include: measuring the resonant frequency of the LC resonance based on the inductance of the pickup coil 221 having an inductance for measuring the eddy current characteristics of the folded portion 115 (S123). That is, the measurement step ( Figure 6 The magnetic field-based characteristics of S120 may include the magnetic field-based eddy current characteristics of the fold 115.

[0072] The generation steps of the method for detecting defects in the folded portion of the battery cell outer casing material according to an embodiment of the present invention ( Figure 6 S130 may include: the controller 230 generating defect (e.g., crack) information of the fold 115 based on whether there is an inductance or a coordinate with a resonant frequency that exceeds the reference range in multiple coordinates of the fold 115 (S132), and excluding the cell with the detected crack from the battery module (including multiple cells) (S145).

[0073] Although the present invention has been described above through embodiments, the present invention is not limited to the above embodiments. Various modifications can be made by those skilled in the art without departing from the spirit of the present invention as claimed in the claims.

Claims

1. A device for detecting defects in the folded portion of battery cell outer casing material, characterized in that, include: The magnetic field output device outputs a magnetic field to the folds of the outer casing material of the battery cell; A characteristic measuring instrument measures the characteristics of the fold based on the magnetic field; as well as The controller generates defect information of the fold based on the measurement results of the characteristic measuring device.

2. The battery cell outer casing material folding defect detection device according to claim 1, characterized in that, Based on the characteristics of the magnetic field, including the surface resistance of the folded portion, The characteristic measuring instrument measures the surface resistance of the fold.

3. The battery cell outer casing material folding defect detection device according to claim 2, characterized in that, The magnetic field outputter outputs a magnetic field to multiple coordinates of the folded portion based on the movement of either the magnetic field outputter or the battery cell. The controller generates defect information for the folded portion based on whether there are coordinates among the plurality of coordinates where the surface resistance is greater than a reference value.

4. The battery cell outer casing material folding defect detection device according to claim 3, characterized in that, The battery cell is positioned between the magnetic field output device and the characteristic measuring device. The characteristic measuring device has one side, and the battery cell is disposed on that side.

5. The battery cell outer casing material folding defect detection device according to claim 1, characterized in that, The characteristics based on the magnetic field include the eddy current characteristics of the folded portion based on the magnetic field. The characteristic measuring device includes a pickup coil having an inductor for measuring the eddy current characteristics of the fold based on the magnetic field.

6. The battery cell outer casing material folding defect detection device according to claim 5, characterized in that, The characteristic measuring device further includes a measuring circuit that measures the resonant frequency of the LC resonance based on the inductance of the pickup coil.

7. The device for detecting defects in the folded portion of the battery cell casing material according to any one of claims 1 to 6, characterized in that, The magnetic field outputter outputs a magnetic field to multiple coordinates of the folded portion based on the movement of either the magnetic field outputter or the battery cell.

8. The device for detecting defects in the folded portion of the battery cell casing material according to any one of claims 1 to 6, characterized in that, The fold is located at one edge of the outer material. The magnetic field outputter outputs a magnetic field to multiple coordinates of the folded portion based on the one-dimensional movement of the magnetic field outputter and one of the battery cells.

9. The device for detecting defects in the folded portion of the battery cell casing material according to any one of claims 1 to 6, characterized in that, The outer casing material includes an embedded metal layer. The defect information of the folded portion includes crack detection information of the metal layer.

Images