Position defect detection device of electrode of bicell and position defect detection method thereof

Abstract

The electrode position defect detection device of the present invention is an electrode position defect detection device of a bicell in which a separator and an anode are located between a cathode and a bicell, and comprises: a conductor installed in contact with or adjacent to a side of the bicell where a tab is not installed; a power source electrically connected to the anode tab of the bicell and the conductor, respectively, to apply a predetermined potential to the anode tab and the conductor; and a measuring device that detects whether current flows between the conductor and the anode when the predetermined potential is applied. The present invention also relates to a detection method for detecting electrode position defects in a bicell.

Description

Technology Field

[0001] The present invention relates to a device and method for detecting electrode position defects in a bicell.

[0002] More specifically, the invention relates to a detection device and a detection method for detecting a faulty anode position in a bicell in which a separator and an anode are located between cathodes. Background Technology

[0004] With the technological development and increasing demand for mobile devices, the demand for rechargeable batteries is also rising rapidly. In particular, lithium-ion batteries are widely used as an energy source for various electronic products as well as mobile devices, due to their high energy density and operating voltage, as well as their excellent storage and lifespan characteristics.

[0005] Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries according to the shape of the battery case. The electrode assembly mounted inside the battery case is a power generation device capable of charging and discharging, consisting of a stacked structure of electrodes and a separator. Depending on its structure, the electrode assembly can be broadly classified into jelly-roll type (wound type), stack type (laminated type), and a stack / folding type, which is a mixed form thereof.

[0006] These electrode assemblies are manufactured in the form of unit cells by laminating electrodes and separators during a lamination process. The unit cells can be stacked in a monocell configuration of anode, separator, and cathode, or in so-called Type A bicells (anode-separator-cathode-separator-anode) or Type C bicells (cathode-separator-anode-separator-cathode). Here, it is important to manufacture the electrode assembly by stacking multiple electrodes and separators in precise positions. If the electrodes and separators are not aligned in the correct positions, a short circuit may occur between the electrodes, potentially leading to ignition or damage to the secondary battery.

[0007] The electrodes and separator forming the bicell are typically configured so that the surface area increases in the order of the anode, cathode, and separator. In the case of a Type A bicell in which the cathode is located in the middle, misalignment can be easily detected even if the anode and cathode are not aligned in precise positions. That is, since the cathode, which has a large surface area, is located in the middle of the Type A bicell, it is easy to identify if the position of the cathode is off-center relative to the anode. Although the large separator between the anode and cathode may obstruct the view, since the separator is a thin resin film, when lighting such as an LED is shone from one side of the bicell, the light passes through the separator, allowing the shape and position of the cathode to be easily determined.

[0008] However, in the case of a Type C bicell where a small-area anode is located in the middle, large-area cathodes are positioned on both sides of the bicell; therefore, it is very difficult to detect misalignment even if the anode is positioned off-center relative to the cathode. This is because the cathode consists of an active material coated on a metal current collector, so even when illuminated as described above, light cannot penetrate the cathode, making it impossible to determine the position of the anode.

[0009] As such, in the case of Type C bicells, there is a problem in identifying the location of the anode because the anode located in the middle is smaller than the cathode and its top and bottom surfaces are surrounded by the cathode. If a final battery cell is manufactured using a unit cell where the anode is not located in the center but is offset to one side, lithium precipitation may occur at the tip of the anode, leading to more serious problems such as internal short circuits and insulation weakening. Therefore, such cells must be detected during the manufacturing process to ensure they are not produced as final product cells.

[0011] Therefore, the development of a technology capable of identifying defects in the anode position in Type C bicells is desired. Prior art literature

[0013] Republic of Korea Registered Patent Publication No. 10-2173030 The problem to be solved

[0014] The present invention is designed to solve the above-mentioned problems and aims to provide a bicell electrode position defect detection device and a detection method capable of detecting an anode position defect in a bicell where the anode is located between the cathodes during processes such as lamination. means of solving the problem

[0016] The electrode position defect detection device of the present invention for solving the above problem is,

[0017] A device for detecting electrode position defects in a bicell having a separator and an anode located between a cathode and a positive electrode, comprising: a conductor installed in contact with or adjacent to a side of the bicell where a tab is not installed; a power source electrically connected to the positive electrode tab of the bicell and the conductor, respectively, to apply a predetermined potential to the positive electrode tab and the conductor; and a measuring device for detecting whether current flows between the conductor and the positive electrode when the predetermined potential is applied.

[0018] As an example, the above measuring device may be a measuring device in which the power supply is integrated as a whole.

[0019] Specifically, the measuring device may be a HI-POT measuring device that measures at least one of the microcurrent and insulation resistance between the conductor and the anode.

[0020] As an example, the conductor is installed in contact with or adjacent to the separator of the bicell. Additionally, the conductor must be installed so as not to come into contact with the positive and negative electrodes of the bicell.

[0021] As a specific example, the conductor may be a metal plate extending along the longitudinal direction of the bicell. Additionally, the metal plate may be installed perpendicular to the longitudinal direction of the bicell.

[0022] As an example, the conductor may have facing portions that are in contact with or adjacent to the separator on all sides where the tab of the bicell is not installed.

[0023] As a specific example, the conductor may be formed in a shape that surrounds the remaining sides, excluding the side where the positive tab of the bicell is installed.

[0024] Specifically, if the bicell is a bidirectional type bicell in which the positive tab and the negative tab are located in opposite directions, the portion of the conductor facing the negative tab of the bidirectional type bicell may be arranged to be spaced apart from the negative tab.

[0025] Alternatively, if the bicell is a unidirectional type bicell in which the positive tab and the negative tab are located in the same direction, the conductor may be positioned in contact with or adjacent to the remaining side, excluding the side where the tabs of the unidirectional type bicell are installed.

[0026] As another example, the conductor is formed in a shape that surrounds all sides of the bicell, and the side portion of the conductor facing the side where the positive tab of the bicell is installed may be spaced apart from the positive tab.

[0027] In this case, an opening for passing a wire to connect the power source and the positive tap may be formed in the side portion.

[0028] As one aspect of the present invention, a method for detecting a faulty electrode position in a bicell comprises: a step of installing a conductor in contact with or adjacent to a side of the bicell where a tab is not installed, in which a separator and an anode are located between the cathodes; a step of electrically connecting a power source and a measuring instrument to the tab of the anode of the bicell and the conductor, respectively; and a step of determining a faulty position of the anode by detecting whether current flows between the conductor and the anode when a predetermined potential is applied to the tab of the anode and the conductor by the power source.

[0029] As another aspect of the present invention, a method for detecting a faulty electrode position in a bicell comprises the steps of: electrically connecting a power source and a measuring device to a positive electrode tab of a bicell in which a separator and a positive electrode are located between a conductor and a negative electrode; installing the conductor in contact with or adjacent to a side of the bicell where the tab is not installed; and determining a faulty position of the positive electrode by detecting whether current flows between the conductor and the positive electrode when a predetermined potential is applied to the positive electrode tab and the conductor by the power source. Effects of the invention

[0031] According to the present invention, a defect in the position of the positive electrode of a so-called Type C bicell can be detected. By doing so, it is possible to prevent short circuits and insulation deterioration in the battery cell.

[0032] In addition, according to the electrode position defect detection device of one embodiment of the present invention, since the position defect of the anode can be detected from multiple sides of the bicell at once, there is an advantage in that the electrode position defect of the bicell can be detected quickly. Brief explanation of the drawing

[0034] FIG. 1 is a schematic diagram and a partially enlarged side cross-sectional view showing the configuration of a device for detecting electrode position defects of a bicell according to one embodiment of the present invention. FIG. 2 is a side cross-sectional view showing the defect detection principle by the electrode position defect detection device of the bicell of the present invention. Figure 3 is a schematic diagram showing the configuration of a Hi-Pod measuring device, which is a component of the electrode position defect detection device. FIG. 4 is a schematic diagram showing that the electrode position defect detection device (100) of the bicell of the present invention, to which a high-pot measuring device is applied, is applied to a bidirectional type bicell assembly (10) and a unidirectional type bicell (10') assembly, respectively. FIG. 5 is a schematic diagram showing the configuration of a device for detecting electrode position defects of a bicell according to another embodiment of the present invention. FIG. 6 is a schematic diagram showing the configuration of a device for detecting electrode position defects of a bicell according to another embodiment of the present invention. Specific details for implementing the invention

[0035] The detailed configuration of the present invention will be described below with reference to the attached drawings and various embodiments. The embodiments described below are presented as examples to aid in understanding the present invention, and the attached drawings are not drawn to actual scale to aid in understanding the invention, and the dimensions of some components may be exaggerated.

[0036] The present invention is capable of various modifications and may take various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the invention to the specific disclosed forms, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0038] (First embodiment)

[0039] FIG. 1 is a schematic diagram and a partially enlarged side cross-sectional view showing the configuration of a device for detecting electrode position defects of a bicell according to one embodiment of the present invention.

[0040] The electrode position defect detection device (100) of the bicell according to the present invention is an electrode position defect detection device (100) of a C-type bicell (10) in which a separator (12) and an anode (13) are located between a cathode (11), that is, a cathode (11)-separator (12)-anode (13)-separator (12)-cathode (11). The electrode position defect detection device (100) of the bicell according to the present embodiment comprises: a conductor (20) installed in contact with or adjacent to the side of the bicell (10) where a tab is not installed; and a power source (P / S) electrically connected to the tab (13a) of the anode (13) of the bicell (10) and the conductor (20), respectively, to apply a predetermined potential to the anode tab (13a) and the conductor (20). and a measuring device (30) for detecting whether current flows between the conductor (20) and the positive electrode (13) when the above-mentioned predetermined potential is applied; are included. FIG. 1 discloses a bi-directional type bi-cell (10) in which the tabs (13a, 11a) of the positive electrode (13) and the negative electrode (11) are located in opposite directions as a bi-cell. In the overall schematic diagram on the left side of FIG. 1, the separator (12) and the negative electrode (11) at the bottom of the bi-cell (10) are not shown for convenience of illustration. However, the stacked structure of the bi-cell (10) is fully disclosed in the enlarged side cross-sectional view on the right side of FIG. 1. As shown in FIG. 1, the negative electrode (11) and the negative electrode tab (11a) are arranged at the top of the bi-cell (10), and the positive electrode (13) and the positive electrode tab (13a) are arranged below them in the opposite direction to the negative electrode tab (11a).

[0041] In the present invention, to detect electrode position defects, specifically anode position defects, a method of shining LED light as in the past is not adopted, but rather a method of electrically detecting the position of an unsuitable anode (13) is adopted. That is, the electrode position defect detection device (100) of the present invention is provided with a conductor (20) installed on the side of a C-type bicell (10) where electrode tabs (negative tab and positive tab) are not installed, as shown in FIG. 1. The conductor (20) is a highly electrically conductive metal, such as copper. In addition, the present invention is provided with a power supply (P / S) that is electrically connected to the positive tab (13a) and the conductor (20), respectively, to apply a predetermined potential to the positive tab (13a) and the conductor (20) of the bicell (10). Furthermore, the present invention is provided with a measuring device (30) that detects whether current flows between the conductor (20) and the anode (13), and the measuring device (30) is connected to the power supply (P / S). As illustrated in FIG. 1, the conductor (20)-power supply (P / S)-measuring device (30)-positive tab (13a) cannot form an electrically complete circuit because the conductor (20) and the positive tab (13a) are not electrically connected. Therefore, even if a high potential is applied to the conductor (20) and the positive tab by the power supply (P / S), no current flows between the conductor (20) and the positive (13). That is, as shown in the enlarged side cross-sectional view of FIG. 1, if the positive (13) is properly aligned without being disproportionate to the negative (11) and is sufficiently far from the conductor (20), no current flows between the conductor (20) and the positive even if a predetermined potential is applied by the power supply (P / S). Therefore, in this case, the current cannot be detected by the measuring device (30). However, if the positive electrode (13) is positioned to the left or right of the negative electrode (11), the conductor (20) and the positive electrode (13) may be energized by the application of a predetermined potential.

[0042] FIG. 2 is a cross-sectional view showing the defect detection principle by the electrode position defect detection device (100) of the bicell (10) of the present invention.

[0043] As illustrated in FIG. 2(a), when the positive electrode (13) is positioned so as to be offset toward the conductor (20), a spark or arc may be generated between the positive electrode (13) and the conductor (20) by the application of a predetermined potential, thereby generating a minute flow of electricity, i.e., a minute current. Since the conductor (20) is a highly conductive metal and the positive electrode (13) is equipped with a conductive metal current collector such as copper or aluminum, such a minute current is generated by the proximity of the conductive metal. If the positive electrode tab (13a) and the conductor (20) are not electrically connected by a power source (P / S) and a measuring device (30), no significant current is measured even if the conductor (20) and the positive electrode (13) (metal current collector) approach each other. The present invention configures an incomplete electrical circuit with a conductor (20), a power supply (P / S), a meter (30), and a positive tap (13a) as described above, and applies a predetermined potential (e.g., 400V or a relatively high voltage) to this incomplete electrical circuit so that when the conductor (20) and the positive (13) are positioned adjacently, the conductor (20) and the positive (13) are energized, thereby detecting a faulty positive position.

[0044] Meanwhile, FIG. 2(b) corresponds to an enlarged side cross-sectional view of FIG. 1, showing a state in which the positive electrode (13) is moved away from the conductor (20) and aligned in the correct position relative to the negative electrode, or the conductor (20) is separated from the positive electrode (13) by a distance such that no current flows between the positive electrode (13) and the conductor (20). Accordingly, when the state of FIG. 2(b) is reached, the positive electrode position of the bicell (10) can be determined to be correctly aligned, and when current flows between the conductor and the positive electrode in the state of FIG. 2(a) and the measuring instrument detects this, the positive electrode position of the bicell (10) can be determined to be defective. Thus, the present invention is characterized by detecting a defective position of the positive electrode using an electrical method rather than an optical method of illuminating with light as in the conventional method.

[0045] Whether current flows between the conductor and the anode (13) can be detected by measuring either the microcurrent or the insulation resistance between the conductor (20) and the anode (13). That is, when a predetermined potential is applied to the conductor (20) and the anode (13), if the anode (13) is positioned adjacent to the conductor (20) as described above, and a microcurrent between the conductor (20) and the anode (13) is detected by the measuring instrument (30), then the conductor (20) and the anode (13) are in a state of electrical insulation. Furthermore, the conductor (20) and the anode (13) are an incomplete electrical circuit and are in an electrically insulated state unless there is a defect in the position of the anode. Therefore, theoretically, the insulation resistance becomes infinite. However, if the anode (13) is shifted toward the conductor, a microcurrent is generated as described above, which means that the insulation is broken and the insulation resistance has decreased accordingly. Since the insulation resistance is equal to the value obtained by dividing the applied predetermined potential by the microcurrent, it is possible to detect whether there is current flow between the conductor (20) and the positive electrode (13) by measuring the microcurrent or the insulation resistance.

[0046] Although FIG. 1 shows a form in which the power supply (P / S) and the measuring device (30) are separated, the power supply can be integrated into the measuring device to form a power-integrated measuring device. A HI-POT measuring device (30) can be adopted as such a measuring device (30). FIG. 3 is a schematic diagram showing the configuration of a HI-POT measuring device (30), which is a component of the electrode position defect detection device (100). The HI-POT measuring device (30) is equipped with a power supply (31) for applying a predetermined potential to the conductor (20) and the tap (13a) of the positive electrode, and a measuring unit (32) for measuring at least one of a microcurrent and insulation resistance between the conductor (20) and the positive electrode (13).

[0047] Meanwhile, the distance between the conductor (20) and the anode and the predetermined potential are in a proportional relationship. That is, if a strong potential (e.g., 500V) is applied, a microcurrent can be generated even if the distance between the conductor (20) and the anode (13) is far. If a weaker potential (e.g., 400V) is applied, a microcurrent can be generated only if the distance between the conductor (20) and the anode (13) is somewhat close. For example, a certain low high-pot potential that can be applied can be set in the high-pot meter (30), and the location of the anode where a microcurrent is generated even at the low high-pot potential can be determined as defective.

[0048] FIG. 4 is a schematic diagram showing the electrode position defect detection device (100) of the bicell of the present invention, to which a high-pot measuring device is applied, applied to a bi-directional type bicell assembly (10) and a unidirectional type bicell assembly (10'), respectively. In FIG. 4, for convenience of illustration, the separator and the cathode (11) at the bottom of the bicell (10, 10') are not shown. As shown in FIG. 4, a cathode (11) and a cathode tab (11) are arranged at the top of the bicell (10, 10'), and an anode (13) and an anode tab (13a) are arranged below it in the opposite direction (in the case of the bi-directional type bicell (10)) or the same direction (in the case of the unidirectional type bicell (10')) as the cathode tab (11). A conductor (20) is arranged on one side of the bicell where the tab is not installed. The conductor (20) and the positive electrode tab (13a) are electrically connected to a high-pot meter, and the high-pot meter (30) measures whether there is current between the conductor (20) and the positive electrode (13) by applying a predetermined potential by the high-pot meter (30), thereby detecting a defect in the position of the positive electrode.

[0050] Meanwhile, in the present invention, the conductor (20) may be installed on a side other than the side where the tap of the bicell is installed. This is because if the conductor (20) is installed on the side where the tap is installed, an electrical short circuit may occur due to contact between the conductor (20) and the tap, potentially damaging the bicell. Additionally, the conductor (20) may be installed in contact with or adjacent to the side of the bicell. As described above, when a strong potential is applied to the conductor (20) and the anode (13), a positional defect of the anode can be detected even if the conductor (20) is slightly separated from the side of the bicell. However, for the purpose of applying a low high-pot potential and improving detection precision, it is preferable for the conductor (20) to be in contact with the side of the bicell.

[0051] Since the separator (12) has the largest surface area among the elements constituting the C-type bicell, when the conductor (20) is installed in contact with or adjacent to the side of the bicell, the conductor (20) is installed in contact with or adjacent to the separator (12) as shown in FIGS. 1, 2, and 4. In some cases, the conductor (20) can be positioned by pushing it further inward toward the negative electrode (11) or positive electrode (13) while in contact with the separator (12). Since the separator (12) is a flexible resin film, it is easily bent and deformed even when the conductor (20) is pushed in. However, even in this case, the conductor (20) must not come into contact with the positive and negative electrodes of the bicell. This is because if the conductor (20) comes into contact with the positive electrode (13) or negative electrode (11) and an electric potential is applied, an electrical short circuit may occur, potentially damaging the bicell and making it impossible to detect a faulty positive electrode position.

[0052] By increasing the contact area between the conductor (20) and the bicell, or the area where the conductor (20) and the bicell face each other in close proximity, it is possible to easily detect a defect in the position of the positive electrode of the bicell. That is, as shown in FIG. 2(a), the positive electrode may be offset to one side relative to the negative electrode (11), but it may also be positioned at a predetermined angle tilted relative to the negative electrode (11). In such cases, the position of the positive electrode (13) may vary slightly along the longitudinal direction of the bicell. Therefore, it is preferable to install the conductor (20) so that it extends along the longitudinal direction of the bicell. Specifically, the conductor (20) may be configured as a metal plate that extends along the longitudinal direction of the bicell. In this case, to increase the contact area or the facing area, it is preferable to install the metal plate perpendicular to the longitudinal direction of the bicell (see FIG. 1 and FIG. 4).

[0054] (Second embodiment)

[0055] Referring to FIG. 2(a), when the positive electrode (13) is shifted to the left toward the conductor (20), the presence of current between the conductor (20) and the positive electrode (13) can be detected to determine a faulty positive electrode position. However, if the positive electrode (13) is in the position shown in FIG. 2(a) and the conductor (20) is installed on the right side of the bicell, the distance between the conductor (20) and the positive electrode (13) becomes greater. In this case, no current is detected, so the position of the positive electrode (13) can be determined not to be faulty. That is, depending on the installation position of the conductor (20), there may be cases where a faulty positive electrode position cannot be detected. To prevent this, the conductor (20) may be provided with facing portions that are in contact with or adjacent to the separator (12) on all sides where the tab of the bicell is not installed. As one such example, the conductor (20') can be configured as shown in FIG. 5.

[0056] FIG. 5 is a schematic diagram showing the configuration of a bicell electrode position defect detection device (100) according to another embodiment of the present invention. The conductor (20') of FIG. 5 is formed in a shape that surrounds the remaining side, excluding the side where the positive tab (13a) of the bicell is installed. That is, the conductor (20') of this embodiment is configured in a U-shape with the side where the positive tab (13a) of the bicell is installed open. The reason for forming an open part in the conductor (20') is to prevent the positive tab and the conductor from coming into contact, and to introduce wires and terminals for electrical connection between the high-pot meter and the positive tab through this open part.

[0057] FIG. 5(a) shows a conductor (20') positioned on a bidirectional type bicell (10) in which the positive tab (13a) and the negative tab (11) are located in opposite directions. The conductor (20') has three facing portions (A, B, C) that face parts other than the side of the bicell (10) where the positive tab (13a) is located. The portion (B) of the conductor (20') facing the negative tab (11) of the bidirectional type bicell (10) is positioned spaced apart from the negative tab (11) to prevent the occurrence of an electrical short circuit. As illustrated, the high-pot meter can detect whether there is current flow between the positive and the conductor (20') if any of the three facing portions (A, B, C) of the conductor (20') are electrically connected. For example, when the positive electrode (13) is offset to the left or right relative to the negative electrode (11), the conductor (20') is positioned in contact with or adjacent to the bicell on all sides of the bicell (10) on the left and right, so the positional defect of the positive electrode (13) can be detected without omission.

[0058] FIG. 5(b) shows a conductor (20') placed on a unidirectional type bicell (10') in which the positive tab (13a) and the negative tab (11) are located in the same direction. The conductor (20') has three facing portions (A, B, C) that face the side of the bicell (10') where the positive tab (13a) and the negative tab (11) are located. Since both the positive tab (13a) and the negative tab (11a) are located on the same side, the three facing portions (A, B, C) of the conductor (20') are placed in contact with or adjacent to the remaining side of the unidirectional type bicell (10'), excluding the side where the tabs are installed, so that the positional defect of the positive (13) can be detected without omission regardless of which side the positive (13) is skewed.

[0060] (Third embodiment)

[0061] FIG. 6 is a schematic diagram showing the configuration of a device (100) for detecting electrode position defects of a bicell according to another embodiment of the present invention. This embodiment also has a form in which a conductor is provided with a face portion that contacts or is adjacent to the separator of at least all sides of the bicell where the tab is not installed. In this embodiment, the conductor (20) is formed in a shape that surrounds all sides of the bicell, and the side portion of the conductor (20) facing the side where the positive tab (13a) of the bicell is installed is spaced apart from the positive tab. An opening (21) for passing a wire to connect the measuring device and the positive tab (13a) is formed in the side portion of the conductor (20) facing the side where the positive tab (13a) is installed.

[0062] FIG. 6(a) shows a bidirectional type bicell (10) with a conductor (20) installed therein. To prevent a short circuit, the portion (side portion) of the conductor (20) facing the negative tab of the bicell (10) is spaced apart from the negative tab (11a). Since the conductor (20) is also positioned in contact with or adjacent to the sides of the bidirectional type bicell (10) where no tab is installed, the positional defect of the positive electrode can be detected without omission.

[0063] FIG. 6(b) shows a unidirectional type bicell (10') with a conductor (20") installed, wherein the conductor (20") is positioned in contact with or adjacent to all sides except the side where the positive tab (13a) and negative tab (11a) of the bicell are installed. Therefore, the conductor (20") can also detect electrode position defects without omission.

[0065] A method for detecting electrode position defects in a bicell according to the present invention is described with reference to FIGS. 1 to 6. First, a conductor is installed in contact with or adjacent to the side of a bicell, i.e., a C-type bicell, in which a separator and an anode (13) are located between the cathodes. In this case, the conductor must not be in contact with the anode (13) and the cathode of the bicell, but may be installed in contact with or adjacent to the separator (12) of the bicell. If the potential applied between the conductor and the anode (13) is strong, the separator may be pushed into the conductor and positioned closer to the anode.

[0066] Next, a measuring instrument (30) that measures at least one of a power supply (P / S), a microcurrent, and an insulation resistance is electrically connected to the (13a) of the above bicell and the conductor, respectively.

[0067] Next, a positional defect of the anode is determined by applying a predetermined potential to the anode tap (13a) and the conductor by means of a power supply (P / S) and detecting whether current flows between the conductor and the anode (13) using the measuring instrument. Whether current flows between the conductor and the anode can be determined by measuring the microcurrent or insulation resistance between the conductor and the anode. Although the predetermined potential can be applied to the anode tap and the conductor by means of a separate power supply (P / S), for the sake of simplifying the device configuration, it is preferable to connect a measuring instrument equipped with both a power supply capable of applying potential and a measuring unit capable of measuring microcurrent or insulation resistance to the conductor and the anode tap. The aforementioned Hi-Pot measuring instrument is an example of such a measuring instrument.

[0068] As described above, the conductor can be installed on the side of the bicell and then electrically connected to the positive tab of the meter. However, it is also possible to electrically connect the positive tab and the conductor to the power supply and the meter first, and then install the conductor in contact with or adjacent to the side of the bicell where the tab is not installed. In other words, the order of the above processes can be reversed.

[0069] As described above, according to the electrode position defect detection device and detection method of the bicell of the present invention, a position defect of the positive electrode of a Type C bicell, which was difficult to detect by conventional optical methods, can be easily detected. Accordingly, problems such as lithium deposition, internal short circuits in the cell, and insulation weakening caused by the positive electrode position defect can be prevented.

[0071] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application. Explanation of the symbols

[0073] 10: Bidirectional type buy cell 10': Unidirectional type bicell 11: Cathode 11a: Cathode tab 12: Separator 13: Bipolar 13a: Positive tab 20,20',20": Conductor 21: Opening for wire passage A, B, C: Face-to-face 30: (Hi-Pod) Meter 31, P / S: Power 32: Measurement section 100: Electrode position defect detection device

Claims

Claim 1 A bicell electrode position defect detection device comprising: a conductor installed in contact with or adjacent to a side of the bicell where a tab is not installed; a power source electrically connected to the positive tab of the bicell and the conductor, respectively, to apply a predetermined potential to the positive tab and the conductor; and a measuring device that detects whether current flows between the conductor and the positive electrode when the predetermined potential is applied; wherein the bicell electrode position defect detection device detects the positive electrode position defect by the measuring device detecting whether current flows between the conductor and the positive electrode. Claim 2 In claim 1, the measuring instrument is a bicell electrode position defect detection device in which the power supply is integrated as a single unit. Claim 3 In paragraph 2, the measuring device is a bicell electrode position defect detection device that is a HI-POT measuring device for measuring at least one of the microcurrent and insulation resistance between the conductor and the anode. Claim 4 In claim 1, the conductor is a bicell electrode position defect detection device installed in contact with or adjacent to the separator of the bicell. Claim 5 In claim 1, the electrode position defect detection device of a bicell is installed such that the conductor does not come into contact with the positive and negative electrodes of the bicell. Claim 6 In claim 1, the conductor is a metal plate extending along the longitudinal direction of the bicell, and is a bicell electrode position defect detection device. Claim 7 In claim 6, the metal plate is a bicell electrode position defect detection device installed perpendicular to the longitudinal direction of the bicell. Claim 8 In claim 4, the above conductor has facing portions that are in contact with or adjacent to the separator of at least all sides where the tab of the above bicell is not installed. Claim 9 In claim 4, the conductor is a bicell electrode position defect detection device formed in a shape that surrounds the remaining sides, excluding the side where the positive tab of the bicell is installed. Claim 10 In claim 9, the bicell is a bi-directional type bicell in which the positive tab and the negative tab are located in opposite directions, and the electrode position defect detection device of the bicell in which the portion of the conductor facing the negative tab of the bi-directional type bicell is arranged spaced apart from the negative tab. Claim 11 In claim 9, the bicell is a unidirectional type bicell in which the positive tab and the negative tab are located in the same direction, and the conductor is a bicell electrode position defect detection device that is placed in contact with or adjacent to the remaining side excluding the side where the tabs of the unidirectional type bicell are installed. Claim 12 A bicell electrode position defect detection device according to claim 4, wherein the conductor is formed in a shape that surrounds all sides of the bicell, and the side portion of the conductor facing the side where the positive tab of the bicell is installed is spaced apart from the positive tab. Claim 13 In claim 12, a bicell electrode position defect detection device having a wire passage opening formed in the side portion for connecting the power source and the positive tap. Claim 14 In claim 12, the above bicell is a bi-directional type bicell in which the positive tab and the negative tab are located in opposite directions, and the electrode position defect detection device of the bicell in which the portion of the conductor facing the negative tab of the bi-directional type bicell is arranged spaced apart from the negative tab. Claim 15 In Clause 12, the above bicell is a unidirectional type bicell in which the positive tab and the negative tab are located in the same direction, and the conductor is a bicell electrode position defect detection device that is placed in contact with or adjacent to the remaining side excluding the side where the tabs of the unidirectional type bicell are installed. Claim 16 A method for detecting electrode position defects in a bicell, comprising: a step of installing a conductor in contact with or adjacent to a side of a bicell where a tab is not installed, in which a separator and an anode are located between the cathodes; a step of electrically connecting a power source and a measuring device to the tab of the anode of the bicell and the conductor, respectively; and a step of determining a position defect of the anode by detecting whether current flows between the conductor and the anode when a predetermined potential is applied to the tab of the anode and the conductor by the power source. Claim 17 A method for detecting electrode position defects in a bicell, comprising: a step of electrically connecting a power source and a measuring device to the positive tab of a bicell, in which a separator and a positive electrode are located between a conductor and a negative electrode; a step of installing the conductor in contact with or adjacent to the side of the bicell where the tab is not installed; and a step of determining a position defect of the positive electrode by detecting whether current flows between the conductor and the positive electrode when a predetermined potential is applied to the positive tab and the conductor by the power source.

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