Battery cell thickness measuring device and secondary battery laminating device including the same

Abstract

A battery cell thickness measuring device according to one embodiment of the present invention includes: a first pressure roller installed at a first fixed position on a transfer section, which contacts the battery cell as the battery cell passes the first fixed position during transfer and pressurizes the battery cell in the thickness direction; a first pressure sensing film wrapped around the first pressure roller and provided to measure the pressure received from the battery cell while the first pressure roller pressurizes the battery cell; and a control unit provided to calculate the thickness of the battery cell based on the pressure measured by the first pressure sensing film.

Description

Technical Field

[0001] The present invention relates to a battery cell thickness measuring device and a secondary battery laminating device including the same.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0073186 filed on June 7, 2023, and all the contents disclosed in the literature of the Korean patent application are included as part of this specification.

Background Art

[0003] As secondary batteries used in mobile devices, electric vehicles, etc., there is high demand for prismatic secondary batteries, pouch-type secondary batteries, etc.

[0004] In particular, recently, pouch-type batteries with a structure in which a stacked or stacked / folding-type electrode assembly is built into a pouch-type battery case have attracted a lot of attention due to low manufacturing costs, small weight, easy form deformation, etc.

[0005] As a result, in the secondary battery manufacturing process, dimensional management of battery cells is important to achieve consistent quality of the manufactured battery cells.

[0006] FIG. 1 is a schematic diagram showing a conventional battery cell thickness measuring device 10.

[0007] Referring to FIG. 1, the conventional battery cell thickness measuring device 10 has a structure in which a battery cell 50 mounted on the upper surface of a base plate 30 in a stationary state is pressurized using a pressure plate 20.

[0008] At this time, with the battery cell 50 pressurized, the touch portion 41 of a drop gauge 40 is passed through a through-hole 21 perforated in the pressure plate 20 to measure the pressurized depth, and based on this, the thickness of the battery cell 50 is measured.

[0009] However, the battery cell thickness measuring device 10 may damage the battery cell 50 during the process of pressurizing it, and the drop gauge 40 can only measure the thickness of the part of the battery cell 50 where the through-hole 21 is formed, making it difficult to measure the thickness of other parts.

[0010] Furthermore, the touch portion 41 of the drop gauge 40 that contacts the battery cell 50 has poor durability, increasing maintenance and maintenance costs. This not only limits repeated measurements for precise thickness measurement, but also presents a problem in that accurate thickness measurement becomes difficult if foreign matter adheres to the touch portion 41.

[0011] Furthermore, conventional battery cell thickness measuring devices 10 measure the battery cell thickness when the battery cell 50 is stopped, which presents a problem in in-line production processes where the battery cell 50 is continuously moving, as it makes it difficult to measure the thickness of the battery cell 50 in real time. [Overview of the project] [Problems that the invention aims to solve]

[0012] The present invention aims to solve the problem of providing a battery cell thickness measuring device that can measure the thickness of multiple battery cells in real time during the continuous movement of those cells, and a secondary battery laminating device including the same. [Means for solving the problem]

[0013] To solve the above-mentioned problems, a battery cell thickness measuring device according to one embodiment of the present invention includes: a first pressure roller installed at a first fixed position on a transfer section, which contacts the battery cell as the battery cell passes the first fixed position during transfer and pressurizes the battery cell in the thickness direction; a first pressure sensing film wrapped around the first pressure roller and provided to measure the pressure received from the battery cell while the first pressure roller pressurizes the battery cell; and a control unit that calculates the thickness of the battery cell based on the pressure measured by the first pressure sensing film.

[0014] Furthermore, the first pressure-sensing film may be provided such that the pressure it receives from the battery cell increases as the thickness of the battery cell increases.

[0015] Furthermore, the battery cell thickness measuring device may include a first fixed block located at a predetermined distance from the transport unit at the first fixed position, and a first elastic connecting member that elastically connects the first fixed block and the first pressure roller.

[0016] Furthermore, the first pressure roller may be provided so as to be able to rotate idle.

[0017] Furthermore, the control unit may be configured to compare the calculated thickness of the battery cell with a predetermined standard thickness of the battery cell. The control unit may also be configured to calculate the difference between the calculated thickness of the battery cell and a predetermined standard thickness of the battery cell.

[0018] Furthermore, the control unit can determine that the quality of the battery cell is poor if the difference between the predetermined standard thickness of the battery cell and the calculated thickness of the battery cell falls outside the allowable error range.

[0019] Furthermore, the battery cell thickness measuring device may include a display unit that shows the quality status of the battery cell.

[0020] Furthermore, the control unit may be configured to control the operation of the transfer unit based on the quality status of the battery cells.

[0021] Furthermore, the battery cell thickness measuring device may include a second pressure roller installed at a second fixed position spaced apart from a first fixed position along the transport direction of the battery cell, which contacts the battery cell as it passes the second fixed position during transport and pressurizes the battery cell in the thickness direction of the battery cell, and a second pressure sensing film wrapped around the second pressure roller and measuring the pressure received from the battery cell while the second pressure roller is pressurizing the battery cell.

[0022] Further, the battery cell thickness measuring device may include a second fixed block positioned at a predetermined distance from the transfer unit at the second fixed position, and a second elastic connecting member that elastically connects the second fixed block and the second pressing roller.

[0023] Further, the second pressing roller may be provided to be idly rotatable.

[0024] Further, the control unit may be provided to calculate the thickness of the battery cell based on the pressures measured by the first and second pressure sensing films.

[0025] Further, the transfer unit may include a conveyor.

[0026] Further, a laminating device for a secondary battery according to an embodiment of the present invention may include a laminating unit including a rolling roller that rolls a battery cell in which an electrode and a separator are laminated, a transfer unit provided to transfer the battery cell after lamination is completed, and a battery cell thickness measuring device installed on the transfer path of the transfer unit. Further, the battery cell thickness measuring device is installed at a first fixed position on the transfer unit, and when the battery cell being transferred passes through the first fixed position, it contacts the battery cell and presses the battery cell in the thickness direction of the battery cell. It includes a first pressing roller, a first pressure sensing film provided to be wound around the first pressing roller and measure the pressure received from the battery cell while the first pressing roller presses the battery cell, and a control unit that calculates the thickness of the battery cell based on the pressure measured by the first pressure sensing film.

[0027] Further, the control unit may be provided to determine that the quality of the battery cell is defective when the difference between the predetermined standard thickness of the battery cell and the calculated thickness of the battery cell exceeds the allowable error range.

[0028] Further, the control unit may be provided to control the operation of the laminating unit based on the quality state of the battery cell.

[0029] Further, the control unit may be provided to control the operation of the transfer unit based on the quality state of the battery cell.

[0030] Also, according to another aspect of the present invention, there is provided an apparatus for continuously measuring the thickness of a battery cell on a conveyor that sequentially transfers battery cells in which electrodes and a separator are alternately laminated and have a predetermined thickness, the apparatus being installed at a fixed position on the conveyor and contacting the battery cell when the battery cell in transfer passes through the fixed position, and pressurizing the surface of the battery cell while the height varies in the thickness direction of the battery cell, a pressurizing roller; a pressure sensing film wound around the pressurizing roller and measuring the pressure received from the surface of the battery cell while the pressurizing roller pressurizes the battery cell; and a control unit that calculates the thickness of the battery cell based on the pressure measured by the pressure sensing film.

[0031] Also, according to another aspect of the present invention, there is provided an apparatus for continuously measuring the thickness of a battery cell on a conveyor that sequentially transfers battery cells in which electrodes and a separator are alternately laminated and have a predetermined thickness, the apparatus including a first pressurizing roller installed at a first fixed position on the conveyor and contacting the battery cell when the battery cell in transfer passes through the fixed position, and pressurizing the surface of the battery cell while the height varies in the thickness direction of the battery cell; a first pressure sensing film wound around the first pressurizing roller and measuring the pressure received from the surface of the battery cell while the first pressurizing roller pressurizes the battery cell; a second pressurizing roller installed at a second fixed position spaced apart from the first fixed position along the transfer direction of the battery cell and contacting the battery cell when the battery cell in transfer passes through the fixed position, and pressurizing the surface of the battery cell while the height varies in the thickness direction of the battery cell; a second pressure sensing film wound around the second pressurizing roller and measuring the pressure received from the surface of the battery cell while the second pressurizing roller pressurizes the battery cell; and a control unit provided to calculate the thickness of the battery cell based on the pressures measured by the first and second pressure sensing films.

Advantages of the Invention

[0032] As described above, the battery cell thickness measuring device and the secondary battery laminating device including the same according to at least one embodiment of the present invention have the following effects.

[0033] The thickness of a battery cell can be calculated based on the pressure exerted by a pressure-sensing film wrapped around a pressure roller.

[0034] Furthermore, the thickness of the battery cells can be measured in real time as multiple battery cells move in succession.

[0035] Furthermore, the thickness of multiple battery cells can be continuously measured in real time on a conveyor belt where multiple battery cells are continuously moving. [Brief explanation of the drawing]

[0036] [Figure 1] This is a schematic diagram showing a conventional battery cell thickness measuring device. [Figure 2] This figure shows a battery cell thickness measuring device according to one embodiment of the present invention. [Figure 3] Figure 2 is a schematic diagram showing a battery cell. [Figure 4] This is a diagram showing a battery cell thickness measuring device and a secondary battery laminating device according to one embodiment of the present invention. [Modes for carrying out the invention]

[0037] Hereinafter, with reference to the attached drawings, a battery cell thickness measuring device and a secondary battery laminating device including the same, according to one embodiment of the present invention, will be described.

[0038] Furthermore, regardless of the reference numeral used in the drawings, identical or corresponding components are assigned the same or similar reference numerals, redundant explanations are omitted, and the size and shape of each component shown for the convenience of explanation may be exaggerated or reduced.

[0039] Figure 2 shows a battery cell thickness measuring device 100 according to one embodiment of the present invention, Figure 3 is a schematic diagram showing the battery cell E shown in Figure 2, and Figure 4 is a configuration diagram showing a battery cell thickness measuring device and a secondary battery laminating device according to one embodiment of the present invention.

[0040] A battery cell thickness measuring device 100 according to one embodiment of the present invention is a device that continuously calculates the thickness of a battery cell E on a transfer unit 600 that sequentially transfers battery cells E having a predetermined thickness in which electrodes and separation membranes are alternately stacked.

[0041] The battery cell thickness measuring device 100 may include a transfer unit 600 that sequentially transfers battery cells E having a predetermined thickness, in which electrodes and separation membranes are alternately stacked. The transfer unit 600 may include a conveyor or a plurality of transfer rolls. For the sake of explanation, the following description will use the example that the transfer unit 600 is a conveyor.

[0042] The battery cell thickness measuring device 100 may be a device applied to the electrode assembly process in the secondary battery manufacturing process, for example, a device used in the lamination process.

[0043] Referring to Figures 2 and 3, the battery cell E may include electrodes and a separator membrane, and the battery cell E may include a unit cell in which electrodes and separator membranes are alternately stacked. For example, the unit cell may include a first separator membrane 1, a negative electrode 2 stacked on the first separator membrane 1, a second separator membrane 3 stacked on the negative electrode 2, and a positive electrode 4 stacked on the second separator membrane 3.

[0044] A secondary battery laminating apparatus according to one embodiment of the present invention may include a laminating section 1000 including a rolling roller 1100 for rolling a battery cell E on which electrodes and a separation film are laminated, a transfer section 600 provided for transporting the battery cell after lamination is complete, and a battery cell thickness measuring device 100 installed on the transfer path of the transfer section 600.

[0045] The battery cell thickness measuring device 100 is installed in the transfer path M that transports battery cells E after the lamination process is completed to the next process, and can continuously and in real time measure the thickness of multiple battery cells E during transport.

[0046] Furthermore, the battery cell thickness measuring device 100 can contribute to the control of laminate quality by measuring the thickness of the battery cell E.

[0047] For example, if the difference between the thickness of the battery cell E calculated by the battery cell thickness measuring device 100 and the predetermined standard thickness of the battery cell E falls outside the allowable error range, the laminate quality of the battery cell E can be determined to be poor. In this specification, standard thickness means the thickness of a good battery cell after the lamination process.

[0048] Referring to Figures 2 to 4, the battery cell thickness measuring device 100 according to the present invention includes a first pressure roller 110A, a first pressure sensing film 200A, and a control unit 300.

[0049] In this specification, the X-axis direction indicates the transport direction M of the battery cell E, and the Y-axis direction indicates the stacking direction or thickness direction of the battery cell E. Alternatively, the Y-axis direction may be the upward and downward direction of the first pressure roller 110A.

[0050] The first pressure roller 110A is installed at a first fixed position P1 on the transfer section 600 and is configured to pressurize the surface of the battery cell E in the thickness direction (Y-axis direction) as the battery cell E passes the first fixed position P1 during transfer. The first pressure roller 110A may be configured such that its height changes in the thickness direction (Y-axis direction) of the battery cell E when it comes into contact with the battery cell E. That is, during the process of passing the battery cell E, the first pressure roller 110A may be configured to rise by the thickness of the battery cell E. Of course, a force acts on the first pressure roller 110A in a direction that pressurizes the surface of the battery cell E along the thickness direction of the battery cell E.

[0051] Furthermore, the first pressure roller 110A can be installed to be vertically movable along the thickness direction of the battery cell E to a predetermined position (first fixed position). When the battery cell E passes through the first fixed position P1, it can be positioned between the transfer unit 600 and the first pressure roller 110A.

[0052] Furthermore, the first pressure roller 110A can be separated from the upper surface of the transfer section 600, forming a space through which the battery cell E passes. The size of this space can be changed according to the thickness of the battery cell E.

[0053] The first pressure-sensing film 200A is wound around the first pressure roller 110A and is configured to measure the pressure received from the surface of the battery cell E while the first pressure roller 110A pressurizes the battery cell E.

[0054] The pressure received by the first pressure-sensing film 200A can change depending on the thickness of the battery cell E, and as a result, the pressure measured by the first pressure-sensing film 200A can change depending on the thickness of the battery cell E.

[0055] Furthermore, the first pressure-sensing film 200A may be configured to measure pressure continuously and in real time. For example, the control unit 300 can measure pressure in time units of 50 ms or less, 30 ms or less, 20 ms or less, 10 ms or less, 5 ms or less, or 1 ms or less.

[0056] Furthermore, the control unit 300 calculates the thickness of the battery cell E based on the pressure measured by the first pressure-sensing film 200A. The control unit 300 can continuously calculate the thickness of the battery cell E from the pressure measured by the first pressure-sensing film 200A.

[0057] For example, if the battery cell E includes a first separator membrane 1, a negative electrode 2 laminated on the first separator membrane 1, a second separator membrane 3 laminated on the negative electrode 2, and a positive electrode 4 laminated on the second separator membrane 3, the first pressure roller 110A rises along the thickness direction (Y-axis direction) of the battery cell as the battery cell E passes through the first pressure roller 110A during transport.

[0058] When the first pressure roller 110A comes into contact with the positive electrode surface that forms the uppermost surface of the battery cell E, the pressure measured by the first pressure sensing film 200A during the process of passing over the positive electrode surface of the battery cell E may be a constant value or measured within a predetermined range, and the control unit 300 can calculate the thickness of the battery cell E based on the pressure applied to the positive electrode surface.

[0059] The control unit 300 can calculate the thickness of multiple battery cells E for each pressure measurement time. Based on the length corresponding to the transport direction M of the battery cells E, which the user already knows, the user can determine the position of the battery cell E corresponding to the thickness value provided by the control unit 300.

[0060] Furthermore, the control unit 300 can use a computer program to calculate the thickness of the battery cell E from the pressure received by the first pressure-sensing film 200A.

[0061] For example, the control unit 300 can measure the thickness of the battery cell E based on data obtained by pre-storing the relationship between the pressure of the first pressure-sensing film 200A and the thickness of the battery cell E.

[0062] Furthermore, the battery cell thickness measuring device 100 according to one embodiment of the present invention may include a storage unit that stores thickness data information of the battery cell E corresponding to the pressure of the first pressure sensing film 200A.

[0063] The control unit 300 can use the stored data information to calculate the thickness of the battery cell E corresponding to the pressure measured by the first pressure sensing film 200A. For example, the data information may include information that when the pressure measured by the first pressure sensing film 200A (a value measured as it passes through the positive electrode surface of the battery cell) is value A, the thickness of the battery cell E is value B, and when the pressure measured by the first pressure sensing film 200A (a value measured as it passes through the positive electrode surface of the battery cell) is value C, the thickness of the battery cell E is value D. If the pressure measured by the first pressure sensing film 200A is value A, the control unit 300 can calculate value B, which is the thickness of the battery cell E corresponding to value A stored in the data information, and provide it to the user.

[0064] For example, the thicker the battery cell E, the greater the pressure the first pressure sensing film 200A receives from the surface of the battery cell E. The thicker the battery cell E, the greater the force applied to the first pressure sensing film 200A from the surface of the battery cell E it contacts, and the greater the pressure it receives.

[0065] The battery cell thickness measuring device 100 may include a first fixed block 400A located at a predetermined distance from the upper surface of the transfer unit 600 at the first fixed position P1, and a first elastic connecting member 500A that elastically connects the first fixed block 400A and the first pressure roller 110A. The first elastic connecting member 500A may include a spring.

[0066] The first elastic connecting member 500A is elastically connected to the first fixed block 400A, allowing the first pressure roller 110A to move up and down at a predetermined position (first fixed position) in accordance with the change in thickness of the battery cell E. For example, as the first pressure roller 110A passes through the battery cell, the first pressure roller 110A rises and the first elastic connecting member 500A is compressed. When the first pressure roller 110A detaches from the battery cell after passing through it, the first pressure roller 110A descends and the compression of the first elastic connecting member 500A is released.

[0067] The battery cell thickness measuring device 100 may include a first mounting frame 150A on which the first pressure roller 110A is rotatably mounted at a first fixed position P1.

[0068] At this time, the first mounting frame 150A is elastically connected to the first fixing block 400A by the first elastic connecting member 500A, so that the first mounting frame 150A can be raised and lowered at a predetermined position (first fixed position) in accordance with the change in thickness of the battery cell E.

[0069] In one example, the first pressure roller 110A may be provided so as to be idle rotatable. That is, the first pressure roller 110A may be mounted on the first mounting frame 150A so as to be idle rotatable. When the battery cell E passes the first fixed position P1, the first pressure roller 110A can idle rotate along the surface of the battery cell E while maintaining contact with the surface of the battery cell E.

[0070] In one embodiment, the first pressure-sensing film 200A is not particularly limited in type, as long as it is a product that is wound around the first pressure roller 110A in film form and capable of measuring externally applied pressure; for example, a product from Kaitronics could be used.

[0071] The control unit 300 may be configured to determine the quality of the battery cell E based on the calculated thickness of the battery cell E. By determining the quality (lamination quality) of the battery cell E, consistent quality control of the battery cell E may be possible.

[0072] For example, the control unit 300 can determine that the quality of the battery cell E is poor if the difference between the predetermined standard thickness of the battery cell E and the calculated thickness of the battery cell E falls outside the allowable error range. For example, if the battery cell thickness measuring device 100 according to the present invention is applied to a lamination process, the poor quality may mean poor lamination quality.

[0073] Furthermore, the control unit 300 can determine that the quality of the battery cell E is normal or good if the difference between the predetermined standard thickness of the battery cell E and the calculated thickness of the battery cell E is within the allowable error range.

[0074] Furthermore, the battery cell thickness measuring device 100 may include a display unit 700 that displays the quality status of the battery cell E. The display unit 700 can display on its screen whether the quality status of the battery cell E is good or bad.

[0075] Furthermore, the battery cell thickness measuring device 100 may include a notification unit that emits a warning sound if the quality of the battery cell E is poor.

[0076] Furthermore, the control unit 300 can control the operation of the transfer unit 600 based on the quality status of the battery cells E. For example, if the quality of the battery cells E is poor, the control unit 300 can stop the operation of the transfer unit 600. Through this, excellent quality control of the battery cells E can be achieved by preventing poor-quality battery cells E from mixing with good-quality battery cells E.

[0077] Furthermore, the battery cell thickness measuring device 100 may be configured to measure the thickness of the battery cell E at multiple positions along the transport direction M of the battery cell E.

[0078] The battery cell thickness measuring device 100 may include a second pressure roller 110B and a second pressure sensing film 200B.

[0079] The second pressure roller 110B is provided at a second fixed position P2 on the transfer section 600, and is configured to apply pressure to the battery cell E in the thickness direction (Y-axis direction) when the battery cell E passes the second fixed position P2 during transfer.

[0080] The second pressure roller 110B may be configured such that its height changes in the thickness direction (Y-axis direction) of the battery cell E when the battery cell E comes into contact with it. That is, the second pressure roller 110B may be configured to rise by the thickness of the battery cell E during the process of passing the battery cell E. Of course, a force acts on the second pressure roller 110B in a direction that pressurizes the surface of the battery cell E along the thickness direction of the battery cell E.

[0081] Furthermore, the second pressure roller 110B is provided at a second fixed position P2 located at a distance from the first fixed position P1 along the transport direction of the battery cell E, and is positioned to come into contact with the battery cell E when it passes the second fixed position P2 during transport.

[0082] Furthermore, the second pressure roller 110B can be installed to be vertically movable along the thickness direction of the battery cell E to a predetermined position (second fixed position). When the battery cell E passes through the second fixed position P2, it can be positioned between the transfer unit 600 and the second pressure roller 110B.

[0083] Furthermore, the second pressure roller 110B can be separated from the upper surface of the transfer section 600, forming a space through which the battery cell E passes. The size of this space may vary depending on the thickness of the battery cell E.

[0084] The second pressure-sensing film 200B is wound around the second pressure roller 110B and is configured to measure the pressure received from the surface of the battery cell E while the second pressure roller 110B pressurizes the battery cell E.

[0085] The pressure received by the second pressure-sensing film 200B can change depending on the thickness of the battery cell E, and as a result, the pressure measured by the second pressure-sensing film 200B can change depending on the thickness of the battery cell E.

[0086] Furthermore, the second pressure-sensing film 200B may be configured to measure pressure continuously and in real time. For example, the control unit 300 can measure pressure in time units of 50 ms or less, 30 ms or less, 20 ms or less, 10 ms or less, 5 ms or less, or 1 ms or less.

[0087] Furthermore, the control unit 300 calculates the thickness of the battery cell E based on the pressure measured by the second pressure-sensing film 200B. The control unit 300 can continuously calculate the thickness of the battery cell E from the pressure measured by the second pressure-sensing film 200B.

[0088] Furthermore, the control unit 300 calculates the thickness of the battery cell E based on the pressure measured by the first pressure-sensing film 200A. The control unit 300 can continuously calculate the thickness of the battery cell E from the pressure measured by the first pressure-sensing film 200A.

[0089] For example, if the battery cell E includes a first separator membrane 1, a negative electrode 2 laminated on the first separator membrane 1, a second separator membrane 3 laminated on the negative electrode 2, and a positive electrode 4 laminated on the second separator membrane 3, the second pressure roller 110B rises along the thickness direction (Y-axis direction) of the battery cell as the battery cell E passes through the second pressure roller 110B during transport.

[0090] When the second pressure roller 110B comes into contact with the positive electrode surface that forms the uppermost surface of the battery cell E, the pressure measured by the second pressure sensing film 200B during the process of passing over the positive electrode surface of the battery cell E may be a constant value or measured within a predetermined range, and the control unit 300 can calculate the thickness of the battery cell E based on the pressure applied to the positive electrode surface.

[0091] The battery cell thickness measuring device 100 may include a second fixing block 400B located at a predetermined distance from the upper surface of the transfer unit 600 at the second fixing position P2, and a second elastic connecting member 500B that elastically connects the second fixing block 400B and the second pressure roller 110B. The second elastic connecting member 500B may include a spring.

[0092] The second elastic connecting member 500B is elastically connected to the second fixed block 400B, allowing the second pressure roller 110B to move up and down at a predetermined position in accordance with the change in the thickness of the battery cell E.

[0093] For example, as the second pressure roller 110B passes through the battery cell, the second pressure roller 110B rises and the second elastic connecting member 500B is compressed. When the second pressure roller 110B detaches from the battery cell after passing through it, the second pressure roller 110B descends and the compression of the second elastic connecting member 500B is released.

[0094] The battery cell thickness measuring device 100 may include a second mounting frame 150B on which the second pressure roller 110B is rotatably mounted at a second fixed position P2.

[0095] At this time, the second mounting frame 150B is elastically connected to the second fixing block 400B by the second elastic connecting member 500B, so that the second mounting frame 150B can be raised and lowered at a predetermined position (second fixed position) in accordance with the change in thickness of the battery cell E.

[0096] In one example, the second pressure roller 110B may be provided to be idle-rotatable. That is, the second pressure roller 110B may be mounted on the second mounting frame 150B to be idle-rotatable. When the battery cell E passes the second fixed position P2, the second pressure roller 110B can idle-rotate along the surface of the battery cell E while maintaining contact with the surface of the battery cell E.

[0097] In one embodiment, the second pressure-sensing film 200B is not particularly limited in type, as long as it is a product that can measure externally applied pressure and is wound around the second pressure roller 110B in film form; for example, a product from Kaitronics could be used.

[0098] In this specification, the method of measuring the thickness of the battery cell E via the first pressure-sensing film 200A at the first fixed position P1 and the method of measuring the thickness of the battery cell E with the second pressure-sensing film 200B at the second fixed position P2 are the same.

[0099] The battery cell thickness measuring device 100 can improve the reliability of the calculated battery cell E thickness measurement by installing multiple pressure rollers at multiple fixed positions.

[0100] In one example, the control unit 300 can calculate the average thickness of the battery cell from the average value of the pressure values ​​measured by a plurality of pressure-sensing films 200A and 200B, thereby improving the reliability of the measured thickness of the battery cell.

[0101] A secondary battery laminating apparatus according to one embodiment of the present invention may include a laminating section 1000 that laminates a battery cell E having a predetermined thickness in which electrodes and a separation film are alternately stacked.

[0102] Furthermore, the secondary battery laminating apparatus may include a transfer unit 600 for continuously transferring a plurality of laminated battery cells.

[0103] Furthermore, the secondary battery laminating apparatus includes a battery cell thickness measuring device 100 installed on the transport path of the transport unit 600. The battery cells E transported to the transport unit 600 may be battery cells E that have already undergone the lamination process.

[0104] As described above, the battery cell thickness measuring device 100 may include: one or more pressure rollers installed at one or more fixed positions on the transfer section 600, which pressurize the surface of the battery cell E while changing height in accordance with the change in thickness of the battery cell E as the battery cell E passes the fixed position during transfer; a pressure sensing film wrapped around the pressure rollers and provided to measure the pressure received from the surface of the battery cell E while the pressure rollers pressurize the battery cell E; and a control unit provided to calculate the thickness of the battery cell E based on the pressure measured by the pressure sensing film.

[0105] Furthermore, the control unit 300 may be configured to control the operation of the laminating unit 1000 based on the quality status of the battery cells.

[0106] The laminating section 1000 may include a pair of rolling rollers 1100, and may have a structure that allows the battery cell E to pass between the pair of rolling rollers 1100 during the laminating process.

[0107] The control unit 300 can determine that the quality of the battery cell E is poor if the difference between the predetermined standard thickness of the battery cell E and the calculated thickness of the battery cell E falls outside the allowable error range. At this time, the control unit 300 can also adjust the distance between the pair of rolling rollers 1100, and the control unit 300 can also adjust the load applied to the pair of rolling rollers 1100.

[0108] Furthermore, the control unit may be configured to control the operation of the transfer unit 600 based on the quality status of the battery cells. In one example, the control unit 300 can stop the operation of the transfer unit 600 if the quality of the battery cells E is poor, thereby preventing poor-quality battery cells E from mixing with good-quality battery cells E.

[0109] The preferred embodiments of the present invention described above are disclosed for illustrative purposes only, and a person skilled in the art with ordinary skill in the invention will know that various modifications, alterations, and additions are possible within the spirit and scope of the invention, and such modifications, alterations, and additions should be considered to fall within the claims below. [Industrial applicability]

[0110] According to at least one embodiment of the present invention, a battery cell thickness measuring device and a secondary battery laminating device including the same, the thickness of a battery cell can be measured in real time as a plurality of battery cells move continuously.

Claims

1. A first pressure roller is installed at a first fixed position on the transfer section, and when a battery cell is being transferred, it comes into contact with the battery cell and applies pressure to the battery cell in the thickness direction of the battery cell. A first pressure-sensing film is wound around the first pressure roller and is provided to measure the pressure received from the battery cell while the first pressure roller pressurizes the battery cell, A battery cell thickness measuring device, comprising: a control unit that calculates the thickness of the battery cell based on the pressure measured by the first pressure-sensing film.

2. The battery cell thickness measuring device according to claim 1, wherein the first pressure sensing film is provided such that the pressure received from the battery cell increases as the thickness of the battery cell increases.

3. A first fixed block located at a predetermined distance from the transfer unit at the first fixed position, The battery cell thickness measuring device according to claim 1, further comprising a first elastic connecting member that elastically connects the first fixing block and the first pressure roller.

4. The battery cell thickness measuring device according to claim 1, wherein the first pressure roller is provided so as to be able to rotate at idle.

5. The battery cell thickness measuring device according to claim 1, wherein the control unit is provided to calculate the difference between the calculated thickness of the battery cell and a predetermined standard thickness of the battery cell.

6. The battery cell thickness measuring device according to claim 5, wherein the control unit determines that the quality of the battery cell is poor if the difference between a predetermined standard thickness of the battery cell and the calculated thickness of the battery cell falls outside the allowable error range.

7. The battery cell thickness measuring device according to claim 6, further comprising a display unit for displaying the quality status of the battery cell.

8. The battery cell thickness measuring device according to claim 6, wherein the control unit is provided to control the operation of the transfer unit based on the quality status of the battery cell.

9. A second pressure roller is installed at a second fixed position spaced apart from the first fixed position along the transport direction of the battery cell, and contacts the battery cell as it passes the second fixed position during transport, thereby applying pressure to the battery cell in the thickness direction of the battery cell. The battery cell thickness measuring device according to claim 1, further comprising: a second pressure sensing film wound around the second pressure roller, which measures the pressure received from the battery cell while the second pressure roller pressurizes the battery cell.

10. The battery cell thickness measuring device according to claim 9, wherein the control unit is provided to calculate the thickness of the battery cell based on the pressure measured by the first pressure sensing film and the second pressure sensing film.

11. The battery cell thickness measuring device according to claim 1, wherein the transfer section includes a conveyor.

12. A laminate section including rolling rollers for rolling a battery cell in which electrodes and a separation membrane are stacked, A transfer unit is provided to transport the battery cells after lamination is complete, A laminating apparatus for secondary batteries, comprising a battery cell thickness measuring device according to claim 1, which is installed on the transport path of the transport unit.

13. The laminating apparatus for secondary batteries according to claim 12, wherein the control unit determines that the quality of the battery cell is poor if the difference between the predetermined standard thickness of the battery cell and the calculated thickness of the battery cell falls outside the allowable error range.

14. The laminating apparatus for secondary batteries according to claim 13, wherein the control unit is provided to control the operation of the laminating unit based on the quality status of the battery cells.

15. The laminating apparatus for secondary batteries according to claim 13, wherein the control unit is provided to control the operation of the transfer unit based on the quality status of the battery cells.

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