JP2016001195A - Method and system for inspection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for inspecting a lamination film for defects such as a pin-hole or a flaw, the lamination film being formed of a metal layer and an insulating layer on each surface of the metal layer.SOLUTION: The present invention provides a method for inspecting a lamination film for defects, the lamination film being formed of a metal layer and an insulating layer on each surface of the metal layer. The method includes a voltage applying step and a detection step. The lamination films are bonded together so that an external member for containing power generating elements can be made, whereby a second battery is thus formed. The voltage applying step supplies conductive liquid to a surface of the lamination film and applies a voltage between a first electrode in contact with the surface of the lamination film and a second electrode in contact with an edge of a metal layer exposed from an end surface of the film in the secondary battery. The detection step detects the state of the conduction between the first and second electrodes.

Description

  The present invention relates to an inspection method and an inspection system for inspecting a defect of a laminated film in which insulating layers are laminated on both surfaces of a metal layer.

  In recent years, the development of electric vehicles (EVs) and hybrid electric vehicles (HEVs) has been promoted against the background of the increasing environmental protection movement. As a power source for driving these motors, lithium ion secondary batteries that can be repeatedly charged and discharged have attracted attention. A lithium ion secondary battery is formed by accommodating a power generation element in which a plurality of sheet-like positive electrodes and negative electrodes are stacked via a separator in an insulating exterior member. The insulating exterior member is formed by laminating an insulating laminated film in which an insulating layer is laminated on both surfaces of a metal layer.

  As a technique related to this, an inspection apparatus as shown in the following Patent Document 1 has been proposed from the viewpoint of improving the reliability of a film-like insulating member. The inspection apparatus disclosed in Patent Document 1 includes a first electrode on which an insulating member to be inspected is placed, an electrolytic solution supply unit that supplies an electrolytic solution to an upper portion of the insulating member, and a surface of the insulating member A second electrode in contact with the first electrode. According to such a configuration, when the through-hole is formed in the insulating member, if the voltage is applied between the first electrode and the second electrode, the first electrode and the second electrode are brought into contact with each other by the electrolytic solution. Since electricity is supplied, defects such as pinholes and scratches penetrating the insulating member can be detected.

JP 2006-275816 A

  However, in the above inspection apparatus, the first and second electrodes are disposed on the front surface side and the back surface side of the insulating member, respectively. For this reason, in said inspection apparatus, there exists a problem that defects, such as a pinhole and a crack, cannot be detected about the insulating laminated film by which an insulating layer is laminated | stacked on both surfaces of a metal layer.

  The present invention has been made to solve the above-described problems. Accordingly, an object of the present invention is to provide an inspection method and an inspection system capable of inspecting defects in a laminated film in which insulating layers are laminated on both surfaces of a metal layer.

  The above object of the present invention is achieved by the following means.

  The inspection method of the present invention is an inspection method for inspecting a defect of a laminated film in which an insulating layer is laminated on both surfaces of a metal layer, and a power generation element is accommodated by an exterior member formed by bonding the laminated film. The secondary battery is formed, and the inspection method includes a voltage application step and a detection step. In the state in which the secondary battery is formed, the voltage applying step supplies a conductive liquid to the surface of the laminated film, and contacts a surface of the laminated film to which the liquid is supplied. A voltage is applied between the second electrode contacting the end of the metal layer exposed from the end face of the laminated film. In the detecting step, an energization state between the first and second electrodes to which the voltage is applied is detected.

  The inspection system of the present invention is an inspection system for inspecting a defect of a laminated film in which insulating layers are laminated on both surfaces of a metal layer, and the power generation element is accommodated by an exterior member formed by bonding the laminated film. The inspection system includes a liquid supply unit, a first electrode, a second electrode, a voltage application unit, and a detection unit. The liquid supply unit supplies a conductive liquid to the surface of the laminated film in a state where the secondary battery is formed. The first electrode contacts the surface of the laminated film to which the liquid is supplied. The second electrode is in contact with the end portion of the metal layer exposed from the end surface of the laminated film. The voltage application unit applies a voltage between the first and second electrodes in a state where the secondary battery is formed. The detection unit detects an energization state between the first and second electrodes to which the voltage is applied.

  According to the present invention, since the energized state between the surface of the laminated film and the end of the metal layer exposed from the end face of the laminated film is detected, the defect of the laminated film is inspected in the state where the secondary battery is formed. can do.

It is a figure for demonstrating the defect of the laminated | multilayer film inspected by the inspection system concerning one Embodiment of this invention, and a laminated | multilayer film. It is a figure showing a schematic structure of an inspection system concerning one embodiment of the present invention. FIG. 3 is a partially enlarged view of FIG. 2. It is a flowchart which shows the procedure of the test | inspection process performed by the test | inspection system shown in FIG. It is a figure for demonstrating chattering between the 1st and 2nd probes. It is a figure which shows the relationship between the osmosis | permeation time of an electrode solution, and the depth of a defect. It is a flowchart which shows the procedure of the test | inspection process concerning a modification. It is a figure which shows the impedance waveform between the 1st and 2nd probe when a low voltage is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case where the type and depth of defects present in a laminated film of a lithium ion secondary battery are inspected using the inspection system and inspection method of the present invention will be described as an example. In addition, the same code | symbol was used for the same member in the figure.

  FIG. 1 is a view for explaining a laminated film inspected by an inspection system according to an embodiment of the present invention and defects of the laminated film. As shown in FIG. 1, the laminated film 10 of this embodiment includes a metal layer 20, a seal layer 30 formed on one surface of the metal layer 20, and a protective layer 40 formed on the other surface of the metal layer 20. And have.

  The metal layer 20 blocks the electrolytic solution and gas, and is formed of aluminum. The seal layer 30 is for welding the two laminated films 10 to each other, and is formed of polypropylene (PP).

  The protective layer 40 includes a first insulating layer 41 that protects the metal layer 20, and a second insulating layer 42 that is formed between the first insulating layer 41 and the metal layer 20. The first insulating layer 41 is made of polyethylene terephthalate (PET). The second insulating layer 42 is for improving the bondability between the first insulating layer 41 and the metal layer 20 and is made of nylon. In addition, the material which comprises the metal layer 20, the sealing layer 30, the 1st insulating layer 41, and the 2nd insulating layer 42 is not limited to said material.

  Defects 50a, 50b, and 50c such as pinholes and scratches can be formed on the laminated film 10 thus configured. These defects 50a, 50b, and 50c are classified into three types according to their depths.

  Here, the first defect is a defect 50a that does not penetrate the first insulating layer 41 (see FIG. 1A), and the second defect penetrates the first insulating layer 41 and performs second insulation. The defect 50b reaches a part of the layer 42 (see FIG. 1B). The third defect is a defect 50c that penetrates the first and second insulating layers 41 and 42 and reaches the metal layer 20 (see FIG. 1C).

  A lithium ion secondary battery 200 (see FIG. 2) is accommodated in an exterior member formed by laminating the laminated film 10 by accommodating a power generation element in which a plurality of sheet-like positive electrodes and negative electrodes are laminated via a separator. Is formed. In this embodiment, the defect of the laminated film 10 on the surface of the lithium ion secondary battery 200 is inspected. Hereinafter, an inspection system for inspecting the defects of the laminated film 10 will be described.

  FIG. 2 is a diagram showing a schematic configuration of an inspection system according to an embodiment of the present invention, and FIG. 3 is a partially enlarged view of FIG. As shown in FIGS. 2 and 3, the inspection system 100 according to the present embodiment includes first and second probes 110 and 120, a voltage application device 130, and an arithmetic device 140.

  The first probe 110 is in contact with the surface of the laminated film 10 while supplying a conductive liquid. The first probe 110 has a tank part 111, an electrode fixing part 112, and a porous rubber part 113. The tank part 111 accommodates a conductive liquid (hereinafter referred to as an electrode liquid) mainly composed of ethanol. The electrode fixing portion 112 is made of ferrite and holds a copper wire (not shown) inside. Further, the electrode fixing part 112 prevents volatilization or dripping of the electrode liquid from the tank part 111. The porous rubber portion 113 is formed of a porous rubber material and holds the electrode solution. The porous rubber portion 113 is pressed against the surface of the laminated film 10 (see FIG. 3A) and supplies the electrode solution to the surface of the laminated film 10.

  The second probe 120 is in contact with the end surface 20e of the metal layer 20 exposed from the end surface 10e of the laminated film 10 (see FIG. 3B). The second probe 120 is formed of a conductive rubber material having a V-shaped groove, sandwiches the end of the lithium ion secondary battery 200, and the end surface 20 e of the metal layer 20 exposed from the end surface 10 e of the laminated film 10. To touch.

  The voltage application device 130 applies a constant voltage between the first probe 110 and the second probe 120. The first probe 110 is connected to the plus side of the voltage application device 130, and the second probe 120 is connected to the minus side of the voltage application device 130. Further, the voltage application device 130 has a function as an impedance measuring machine, and can measure the impedance value between the first and second probes 110 and 120.

  The arithmetic device 140 detects a defect present in the laminated film 10. The arithmetic device 140 identifies the type of defect present in the laminated film 10 from the impedance value between the first and second probes 110 and 120. In addition, the arithmetic device 140 is configured to calculate a time (hereinafter, referred to as chattering) from the first probe 110 to the surface of the lithium ion secondary battery 200 until the impedance value between the first and second probes 110 and 120 is generated. (Referred to as chattering start time). The arithmetic device 140 stores a defect depth-chattering start time conversion table indicating the relationship between the defect depth and the chattering start time, and the defect depth can be calculated from the chattering start time.

  In the inspection system 100 configured as described above, the type and depth of the defect of the laminated film 10 are inspected by detecting the energization state between the first and second probes 110 and 120. Hereinafter, a method for inspecting defects on the surface of the lithium ion secondary battery 200 in the inspection system 100 according to the present embodiment will be described with reference to FIGS.

  FIG. 4 is a flowchart showing a procedure of inspection processing executed by the inspection system. Prior to the inspection process shown in FIG. 4, the appearance inspection of the lithium ion secondary battery is performed using a camera, and the lithium ion secondary battery in which defects are observed and the lithium ion secondary battery in which no defects are observed are sorted. The In the inspection process of the present embodiment, the type and depth of the defect are inspected for the lithium ion secondary battery in which the defect is observed.

  First, the second probe 120 is brought into contact with the end of the lithium ion secondary battery 200 (step S101). In the present embodiment, the second probe 120 made of a conductive rubber material having a V-shaped groove sandwiches the end of the lithium ion secondary battery 200. When the second probe 120 sandwiches the end portion of the lithium ion secondary battery 200, the end surface 20e of the metal layer 20 exposed from the end surface 10e of the laminated film 10 and the second probe 120 come into contact with each other.

  Subsequently, the first probe 110 is brought into contact with the surface of the lithium ion secondary battery 200 (step S102). In the present embodiment, the porous rubber portion 113 of the first probe 110 is pressed against the region including the defect of the laminated film 10. Since the porous rubber part 113 holds the electrode liquid, the electrode liquid oozes out from the porous rubber part 113 when the porous rubber part 113 is pressed against the laminated film 10, and the surface of the laminated film 10. Supplied. The first probe 110 is brought into contact with the surface of the lithium ion secondary battery 200, and a constant voltage is applied between the first and second probes 110 and 120 by the voltage application device 130.

  Subsequently, it is determined whether or not the impedance value between the first and second probes 110 and 120 is equal to or less than a predetermined value (step S103). In the present embodiment, the impedance value between the first and second probes 110 and 120 to which a constant voltage is applied is measured, and it is determined whether or not the impedance value is a predetermined value (determination level) or less. Here, the predetermined value is a value for determining the energization state / insulation state between the first and second probes 110 and 120, and is, for example, 50Ω.

  When it is determined that the impedance value between the first and second probes 110 and 120 is not less than or equal to the predetermined value (step S103: NO), it is determined that the first and second probes 110 and 120 are in an insulated state. Transition to processing.

  On the other hand, when it is determined that the impedance value between the first and second probes 110 and 120 is equal to or less than the predetermined value (step S103: YES), a defective product is determined (step S104), and the process is terminated. In the present embodiment, the defect 50c (FIG. 1 (C)) is formed between the first and second probes 110 and 120, and passes through the first and second insulating layers 41 and 42 and reaches the metal layer 20. Is determined to be present in the laminated film 10. The lithium ion secondary battery 200 having the defect 50c reaching the metal layer 20 is determined as a defective product.

  As described above, according to the processing shown in steps S101 to S104 in FIG. 4, the energization state between the first and second probes 110 and 120 is detected. By detecting the energization state between the first and second probes 110 and 120, the laminated film 10 has a defect 50 c that penetrates the first and second insulating layers 41 and 42 and reaches the metal layer 20. Is detected.

  On the other hand, in the process shown in step S103, when it is determined that the impedance value between the first and second probes 110 and 120 is not less than or equal to the predetermined value (step S103: NO), it is determined whether chattering has occurred. (Step S105). In the present embodiment, it is determined whether or not chattering in which the impedance value between the first and second probes 110 and 120 greatly fluctuates has occurred.

  FIG. 5 is a diagram for explaining chattering between the first and second probes. FIG. 5A is a diagram illustrating an impedance waveform in which chattering has not occurred, and FIG. 5B is a diagram illustrating an impedance waveform in which chattering has occurred. 5A and 5B, the vertical axis is the impedance value, and the horizontal axis is time. Chattering occurs when a defect 50b (see FIG. 1B) penetrating through the first insulating layer 41 and reaching part of the second insulating layer 42 is present in the laminated film 10. Since the electrode liquid mainly composed of ethanol penetrates into the second insulating layer 42 made of nylon, if the electrode liquid penetrates into the second insulating layer 42 and reaches the metal layer 20, the first and second probes 110. , 120 change from an insulated state to an energized state. Chattering occurs when the first and second probes 110 and 120 change from an insulated state to an energized state. The electrode solution penetrates the second insulating layer 42 over time, and when a certain time (for example, several minutes) elapses, the impedance value between the first and second probes 110 and 120 becomes substantially zero. Chattering is caused by a peeled state between the metal layer 20 and the second insulating layer 42.

  When it is determined in the process shown in step S105 that chattering has not occurred (step S105: NO), the process proceeds to step S109.

  On the other hand, when it is determined that chattering has occurred (step S105: YES), chattering occurrence time is detected (step S106). In the present embodiment, chattering occurs after the first probe 110 contacts the surface of the lithium ion secondary battery 200 in order to calculate the depth of the defect 50b reaching a part of the second insulating layer 42. The time until chattering (chattering start time) is detected.

  Subsequently, the depth of the defect 50b is calculated (step S107). In the present embodiment, the depth of the defect 50b reaching a part of the second insulating layer 42 is calculated from the chattering start time detected in the process shown in step S106.

  FIG. 6 is a diagram showing the relationship between the penetration time of the electrode solution and the depth of the defect. The vertical axis in FIG. 6 is the depth of the defect, and the horizontal axis is the penetration time of the electrode solution. As shown in FIG. 6, the depth of the defect 50b reaching a part of the second insulating layer 42 and the penetration time of the electrode liquid into the second insulating layer 42 are the penetration time as the depth of the defect 50b increases. Has a relationship of shortening. Therefore, the defect depth-chattering start time conversion table showing the relationship between the defect depth and the chattering start time is created in advance, so that the depth of the defect 50b is determined from the chattering start time detected in the process shown in step S106. Can be calculated.

  Subsequently, repair is instructed (step S108), and the process ends. In the present embodiment, repair is instructed on the assumption that the defect 50b reaching the part of the second insulating layer 42 exists in the laminated film 10. In addition, when the defect 50b reaching even a part of the second insulating layer 42 exists in the laminated film 10, a sufficient moisture barrier property cannot be obtained.

  As described above, according to the processing shown in Steps S105 to S108 in FIG. 4, the electrode liquid passes through the second insulating layer 42 and reaches the metal layer 20, so that the first and second probes 110 and 120 are connected. Is detected to change from an insulated state to an energized state. By detecting that the first and second probes 110 and 120 are changed from the insulated state to the energized state, the laminated film 10 has a defect 50b reaching a part of the second insulating layer 42. Is detected. In addition, the depth of the defect 50b is calculated by detecting the chattering start time.

  On the other hand, when it is determined in the process shown in step S105 that chattering has not occurred (step S105: NO), it is determined whether or not a predetermined time has elapsed (step S109). Here, the predetermined time is a time sufficient to confirm that chattering does not occur between the first and second probes 110 and 120, and is, for example, 5 minutes.

  If it is determined that the predetermined time has not elapsed (step S109: NO), the process returns to step S105.

  On the other hand, when it is determined that the predetermined time has elapsed (step S109: YES), repair is instructed (step S110), and the process is terminated. In the present embodiment, the first and second probes 110 and 120 are maintained in an insulated state (see FIG. 5A), and the defect 50a does not penetrate through the first insulating layer 41 (FIG. 1A). Repair is instructed assuming that there is a reference) in the laminated film 10.

  As described above, according to the processing shown in steps S109 and S110 of FIG. 4, the defect 50a that does not penetrate the first insulating layer 41 is not detected because the energization state between the first and second probes 110 and 120 is not detected. The presence of the laminated film 10 is detected.

  And according to the test | inspection system and test | inspection method of this embodiment, a laminated | multilayer film is detected by detecting the energization state between the surface of the laminated film 10 and the end surface 20e of the metal layer 20 exposed from the end surface 10e of the laminated film 10. Ten defects are inspected. Specifically, the defect 50c that reaches the metal layer 20 through the first and second insulating layers 41 and 42, and reaches a part of the second insulating layer 42 through the first insulating layer 41. The defect 50b that is present and the defect 50a that does not penetrate the first insulating layer 41 are inspected.

(Modification)
In the embodiment described above, the depth of the defect 50b penetrating through the first insulating layer 41 and reaching a part of the second insulating layer 42 by using chattering between the first and second probes 110 and 120 is used. Was calculated. However, the process of calculating the depth of the defect 50b may be omitted.

  FIG. 7 is a flowchart illustrating the procedure of the inspection process according to the modification. In the inspection process according to the modification, an applied voltage (for example, 25 V) lower than the applied voltage (for example, 50 V) in the above-described embodiment is applied between the first and second probes 110 and 120. By applying a low voltage, the inrush current is reduced and chattering does not occur between the first and second probes 110 and 120.

  The processing shown in steps S201 to S204 is the same as the processing shown in steps S101 to S104 in FIG. According to the processing shown in steps S201 to S204 in FIG. 7, the defect 50c (see FIG. 1C) penetrating the first and second insulating layers 41 and 42 and reaching the metal layer 20 is formed on the laminated film 10. The presence is detected.

  On the other hand, in the process shown in step S203, when it is determined that the impedance value is not less than or equal to the predetermined value (step S203: NO), repair is instructed (step S205), and the process ends. In this modification, the defect 50b (see FIG. 1B) reaching the part of the second insulating layer 42 through the first insulating layer 41 or the first insulating layer 41 is not penetrated. Repair is instructed assuming that a defect 50a (see FIG. 1A) exists in the laminated film 10.

  FIG. 8 is a diagram showing an impedance waveform between the first and second probes when a low voltage is applied. When a defect 50b reaching a part of the second insulating layer 42 exists in the laminated film 10, if a voltage is applied between the first and second probes 110, 120, the first and second probes 110, Between 120 changes from an insulated state to an energized state (see FIG. 8B). In this modification, by applying a low voltage between the first and second probes 110 and 120, chattering is prevented from occurring when the first and second probes 110 and 120 change from an insulated state to an energized state. Is done. In addition, when the defect 50a which does not penetrate the 1st insulating layer 41 exists in the laminated film 10, between the 1st and 2nd probes 110 and 120 is maintained in an insulated state (refer FIG. 8 (A)). ).

  According to such a configuration, chattering does not occur and a stable impedance waveform can be obtained, so that a defective product or repair can be accurately determined in a short time (for example, within one second).

  As described above, the described embodiment has the following effects.

  (A) In the inspection system and the inspection method of this embodiment, since the energization state between the surface of the laminated film and the end face of the metal layer exposed from the end face of the laminated film is detected, the defect of the laminated film is inspected. Can do.

  (B) When a current-carrying state between the first and second probes is detected, it is determined that there is a defect penetrating the first and second insulating layers and reaching the metal layer. Therefore, the defect reaching the metal layer can be inspected without penetrating the laminated film.

  (C) When it is detected that the electrode liquid penetrates into the second insulating layer and reaches the metal layer, the first and second probes are changed from the insulating state to the energized state. It is determined that there is a defect that penetrates and reaches a part of the second insulating layer. Therefore, it is possible to inspect defects that have not reached the metal layer.

  (D) Defect depth is calculated by detecting the time from the start of supplying the electrode solution to the surface of the laminated film until chattering occurs. Therefore, it is possible to calculate the depth of the defect that penetrates the first insulating layer and reaches a part of the second insulating layer without destroying the laminated film.

  (E) A voltage is applied between the first and second probes so as to prevent chattering. Therefore, it is possible to accurately inspect in a short time a defect that has penetrated through the first and second insulating layers and reached the metal layer, and a defect that has not reached the metal layer. As a result, it becomes possible to apply to in-line inspection in the assembly process of the lithium ion secondary battery.

  (F) Since the first probe includes a porous rubber portion that holds the electrode solution, the electrode solution can be supplied to the laminated film by pressing the porous rubber portion of the first probe against the surface of the laminated film. it can.

  (G) Since the second probe is a conductive elastic member having a V-shaped groove that sandwiches the end of the laminated film, the metal exposed from the end face of the laminated film without damaging the end of the laminated film The end face of the layer can be contacted.

  As described above, in the described embodiment, the inspection system and the inspection method of the present invention have been described. However, it goes without saying that the present invention can be appropriately added, modified, and omitted by those skilled in the art within the scope of the technical idea.

  For example, in the above-described embodiment, the type and depth of the defect are inspected by the inspection system of the present invention on the laminated film in which the defect is previously confirmed by the appearance inspection using the camera. However, the presence / absence of a defect may be directly inspected by the inspection system of the present invention without performing an appearance inspection by a camera.

  In the above-described embodiment, the energization state between the first and second probes is detected by measuring the impedance value between the first and second probes. However, the energization state between the first and second probes may be detected by measuring the current value between the first and second probes.

  In the above-described embodiment, the second probe is brought into contact with the end surface of the end portion of the metal layer exposed from the end surface of the end portion of the laminated film. However, the first and second insulating layers at the end of the laminated film may be removed to expose the end of the metal layer from the end of the laminated film, and the second probe may be in contact with the end of the metal layer.

  In the above-described embodiment, the first probe has a tank part and a porous rubber part, and supplies the electrode solution to the surface of the laminated film. However, a liquid supply device may be provided separately from the first probe, and the electrode liquid may be supplied from the liquid supply device to the surface of the laminated film.

  In the above-described embodiment, the second probe is formed of a conductive rubber material having a V-shaped groove. However, the second probe may be a metal probe.

  In the above-described embodiment, ethanol is used as the conductive liquid. However, the conductive liquid is not limited to ethanol, and various liquids having conductivity can be used.

10 Laminated film,
20 metal layers,
30 sealing layer (insulating layer),
40 protective layer (insulating layer),
41 1st insulating layer (1st insulating layer),
42 2nd insulating layer (2nd insulating layer),
50a, 50b, 50c defects,
100 inspection system,
110 first probe (first electrode, liquid supply unit),
111 tank section,
112 electrode fixing part,
113 Porous rubber part (porous member),
120 second probe (second electrode),
130 voltage application device (voltage application unit, detection unit),
140 Arithmetic unit (determination unit).

Claims (8)

An inspection method for inspecting a defect of a laminated film in which insulating layers are laminated on both surfaces of a metal layer,
A power generation element is accommodated by an exterior member formed by laminating the laminated film to form a secondary battery,
The inspection method is:
In a state where the secondary battery is formed, while supplying a conductive liquid to the surface of the laminated film, from the first electrode that contacts the surface of the laminated film to which the liquid is supplied and from the end face of the laminated film A voltage applying step of applying a voltage between the exposed second end of the metal layer and the second electrode;
A detection step of detecting an energization state between the first and second electrodes to which the voltage is applied;
An inspection method characterized by comprising:   When the energization state between the first and second electrodes is detected in the detection step, it is determined that a defect penetrating the insulating layer and reaching the metal layer is present in the laminated film. The inspection method according to claim 1.   The inspection method according to claim 1, wherein the first electrode includes a porous member that holds the liquid.   The inspection method according to any one of claims 1 to 3, wherein the second electrode is a conductive elastic member having a V-shaped groove portion that sandwiches an end portion of the laminated film. . An inspection system for inspecting defects in a laminated film in which insulating layers are laminated on both sides of a metal layer,
A power generation element is accommodated by an exterior member formed by laminating the laminated film to form a secondary battery,
The inspection system includes:
In a state where the secondary battery is formed, a liquid supply unit that supplies a conductive liquid to the surface of the laminated film;
A first electrode that contacts a surface of the laminated film to which the liquid is supplied;
A second electrode in contact with an end of the metal layer exposed from an end surface of the laminated film;
In a state where the secondary battery is formed, a voltage application unit that applies a voltage between the first and second electrodes;
A detection unit for detecting an energization state between the first and second electrodes to which the voltage is applied;
An inspection system comprising:   And a determination unit that determines that a defect penetrating the insulating layer and reaching the metal layer is present in the laminated film when the detection unit detects an energized state between the first and second electrodes. 6. The inspection system according to claim 5, further comprising:   The inspection system according to claim 5, wherein the first electrode includes a porous member that holds the liquid.   The inspection system according to claim 5, wherein the second electrode is a conductive elastic member having a V-shaped groove that sandwiches an end portion of the laminated film. .