Rewinding stage and secondary battery manufacturing system including the same

Abstract

According to an exemplary embodiment, a rewinding apparatus is provided. The rewinding apparatus includes an unwinder configured to unwind an electrode sheet from a first electrode roll; a scrap port configured to discard defective portions of the electrode sheet; a rewinder configured to wind the electrode sheet onto a second electrode roll; a first rotary encoder configured to sense the length of the electrode sheet unwound by the unwinder in order to generate an input signal; a second rotary encoder configured to sense the length of the electrode sheet wound up by the rewinder in order to generate a consumption signal; and a first controller configured to collect coordinate data indicating a position on the electrode sheet based on the consumption signal.

Description

Technical Field

[0001] The present invention relates to a rewinding stage and a system for manufacturing a secondary battery including the same. This application claims the benefit of Korean Application No. 10-2023-0102905 filed on August 7, 2023 and Korean Application No. 110-2024-0103566 filed on August 5, 2024, which are hereby incorporated by reference in their entirety.

Background Art

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as an energy source for various wireless devices such as handsets, notebook computers, and wireless vacuum cleaners. In recent years, due to improvements in energy density and economies of scale, the manufacturing cost per unit capacity of secondary batteries has decreased dramatically, and as the driving range of battery electric vehicles (BEVs) has increased to a level comparable to that of fuel vehicles, the main application of secondary batteries has shifted from mobile devices to mobility.

[0003] Secondary batteries are manufactured through an electrode process, an assembly process, and an activation process. Among them, the electrode process is the most core process for determining the yield and performance of battery cells. The electrode process can include a coating process, a roll pressing process, and a slitting process. In the coating process, an active material and an insulating material can be coated on the surface of a current collector. In the roll pressing process, the electrode can be pressed by a pressure roll. The roll pressing process can determine the density, performance, and surface quality of the electrode. In the slitting process, the electrode can be cut into a plurality of electrodes according to the design of the battery cell.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technical concept of this invention aims to solve the problem of manufacturing a rewinding stage with improved reliability and traceability, and a secondary battery including the same. [Means for solving the problem]

[0005] According to an exemplary embodiment of the present invention for solving the above-mentioned problems, a rewinding stage is provided. The rewinding stage includes an unwinder configured to unwind an electrode sheet from a first electrode roll; a scrap port configured to discard defective portions of the electrode sheet; a rewinder configured to wind the electrode sheet onto a second electrode roll; a first rotary encoder configured to sense the length of the electrode sheet unwound by the unwinder in order to generate an input signal; a second rotary encoder configured to sense the length of the electrode sheet wound up by the rewinder in order to generate a consumption signal; and a first controller configured to collect coordinate data indicating a position on the electrode sheet based on the consumption signal.

[0006] The first controller described above is configured to collect scrap data indicating the length of the discarded portion of the electrode sheet based on the input signal.

[0007] The system further includes an NG sensor configured to sense NG marks and NG tags on the electrode sheet described above, in order to generate an NG detection signal.

[0008] The first controller described above is configured to collect NG detection data by associating the NG detection signal with the coordinate data described above.

[0009] The first controller described above is configured to control the unwinder and the rewinder based on the NG detection data described above.

[0010] The process further includes a first controller configured to control the unwinder and the rewinder based on the above-mentioned NG detection data.

[0011] The present invention further includes a seam sensor configured to detect seams in the electrode sheets in order to generate a seam detection signal.

[0012] The first controller described above is configured to collect seam detection data by associating the seam detection signal with the coordinate data.

[0013] The system further includes a reference point sensor configured to sense a reference point on the electrode sheet in order to generate a reference point sensing signal.

[0014] The first controller described above is configured to collect reference point sensing data by associating the reference point sensing signal with the coordinate data.

[0015] The first controller is configured to transmit the reference point sensing data to a server, and the server is configured to generate a roll map representing the electrode sheet based on the reference point sensing data.

[0016] The first controller is configured to transmit the reference point sensing data to the second controller, and the second controller is configured to control the unwinder and the rewinder.

[0017] The second controller is configured to transmit the reference point sensing data to a server, and the server is configured to generate a roll map representing the electrode sheet based on the reference point sensing data.

[0018] According to an exemplary embodiment, a secondary battery manufacturing system is provided. The system includes a roll pressing stage configured to perform a rolling process, and a rewinding stage configured to process a first electrode roll processed by the roll pressing stage, the rewinding stage including an unwinder configured to unwind an electrode sheet from the first electrode roll, a scrap port configured to discard defective portions of the electrode sheet, a rewinder configured to wind the electrode sheet onto a second electrode roll, a first rotary encoder configured to sense the length of the electrode sheet unwound by the unwinder to generate an input signal, a second rotary encoder configured to sense the length of the electrode sheet wound up by the rewinder to generate a consumption signal, and a first controller configured to collect coordinate data indicating a position on the electrode sheet based on the consumption signal.

[0019] The first controller described above is configured to collect scrap data indicating the length of the discarded portion of the electrode sheet based on the input signal.

[0020] The system further includes an NG sensor configured to sense NG marks and NG tags on the electrode sheet described above, in order to generate an NG detection signal.

[0021] The first controller described above is configured to collect NG detection data by associating the NG detection signal with the coordinate data described above.

[0022] The first controller described above is configured to control the unwinder and the rewinder based on the NG detection data described above.

[0023] The system further includes a second controller configured to control the unwinder and the rewinder based on the above-mentioned NG detection data. [Effects of the Invention]

[0024] According to an exemplary embodiment of the present invention, a rewinding stage that enables feedback, feedforward, and tracking for an electrode process and a secondary battery manufacturing system including the same can be provided.

[0025] The effects obtainable from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those having ordinary knowledge in the technical field to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects associated with implementing the exemplary embodiments of the present disclosure can also be derived by those having ordinary knowledge in the technical field from the exemplary embodiments of the present disclosure.

Brief Description of the Drawings

[0026] [Figure 1] Shows a secondary battery manufacturing system according to an exemplary embodiment. [Figure 2] Shows a secondary battery manufacturing system according to an exemplary embodiment. [Figure 3] Shows a secondary battery manufacturing system according to an exemplary embodiment. Best Mode for Carrying Out the Invention

[0027] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before that, terms and words used in this specification and the claims should not be construed as being limited to ordinary or dictionary meanings, and should be construed as meanings and concepts consistent with the technical idea of the present invention based on the principle that the inventor can appropriately define the concept of the terms in order to explain his own invention in the best way.

[0028] Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent all of the technical ideas of the present invention, so there can be various equivalents and modifications that can replace them at the time of this application.

[0029] Furthermore, in describing the present invention, if it is determined that a specific description of a related known configuration or function would likely obscure the gist of the invention, such detailed description will be omitted.

[0030] Embodiments of the present invention are provided to give a more complete explanation to an ordinary person of the art; therefore, the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect their actual sizes and proportions.

[0031] (First Embodiment) Figure 1 shows a secondary battery manufacturing system 10 according to an exemplary embodiment.

[0032] Referring to Figure 1, the secondary battery manufacturing system 10 may include a rewinding unit 100, a coating unit 200, a roll pressing unit 300, a slitting unit 400, and a notching unit 500.

[0033] The electrode sheet unwound from the input electrode roll can be processed by one of the following: the die coater of the coating equipment 200, the pressure roll of the roll pressing equipment 300, and the slitting knife of the slitting equipment 400. The processed electrode sheet can then be wound onto the electrode roll. Thus, the processing in the coating equipment 200, roll pressing equipment 300, and slitting equipment 400 for producing electrodes for secondary batteries can be called a roll-to-roll process.

[0034] The coating equipment 200 can perform a coating process on an electrode sheet. The coating process involves applying a coating material, such as an electrode slurry, onto the electrode sheet. The electrode slurry can contain an electrode active material, a conductive material, a binder, and a solvent. An electrode slurry can be provided by dissolving the electrode active material, conductive material, binder, etc., in a solvent.

[0035] The roll pressing equipment 300 can perform a roll pressing process on electrode sheets. The roll pressing process involves passing electrode sheets ES coated with electrode slurry between opposing pressure rolls. The pressure rolls flatten the electrode surface, increasing the bonding force between the active material and the current collector.

[0036] The slitting equipment 400 can perform a slitting process on the electrode sheet. Through the slitting process, the electrode sheet can be separated into multiple electrode sheets.

[0037] The roll-to-roll process is performed on the electrode sheet ES, which is unwound from the first electrode roll ER1 and wound onto the second electrode roll ER2; therefore, the electrode process can also be called a roll-to-roll process.

[0038] The notching equipment 500 can cut the electrode sheet unwound from the electrode roll into the electrode shape of a battery cell. This allows the unit electrode to be formed in the notching equipment 500. The notching equipment 500 can further perform a drying process on either the electrode sheet or the unit electrode.

[0039] If the electrode sheet contains defects, the defects in the electrode sheet can be removed. The defects in the electrode sheet can be removed using either the roll press equipment 300 or the rewinding equipment 100.

[0040] In each of the rewinding units 100, no substantial processing may be performed on the electrode sheet. Each of the rewinding units 100 can change the winding direction of the electrode sheet. Each of the rewinding units 100 can unwind the electrode roll, remove defects from the electrode sheet unwound from the electrode roll, and rewind the electrode sheet from which the defects have been removed. In addition to removing defects from the electrode roll, this allows the outer part of the input electrode roll to be wound inward relative to the output electrode roll. Similarly, the inner part of the input electrode roll to be wound outward relative to the output electrode roll.

[0041] The roll press equipment 300 can remove defects from the electrode sheet during the roll pressing process, or it can remove defects from the electrode sheet without performing the roll pressing process. The operation mode of the roll press equipment 300 that removes only the electrode sheet without performing the roll pressing process is called the rewinding mode. In the rewinding mode, each of the pressure rolls can be moved to a position away from the electrode.

[0042] A unit electrode can be provided by sequentially processing the electrode rolls in the coating equipment 200, roll pressing equipment 300, slitting equipment 400, and notching equipment 500. In the case of a long unit electrode, after the roll pressing process in the roll pressing equipment 300, it can be immediately transferred to the notching equipment 500 without slitting in the slitting equipment 400.

[0043] If there is an excessive number of defects in the electrode rolls processed by the coating equipment 200 and fed into the roll press equipment 300, the defects in the electrode rolls can be removed in the roll press equipment 300. An excessive number of defects in the electrode rolls processed by the coating equipment 200 may include a large number of folded tabs and ring defects.

[0044] If there are too many defects in the electrode rolls processed by the roll press equipment 300, the defective electrode rolls can be removed by either the roll press equipment 300 or the rewinding equipment 100 operating in rewinding mode. The electrode rolls with reduced defects (or no defects) can then be fed into the slitting equipment 400. Excessive defects in the electrode rolls processed by the roll press equipment 300 may include unwinding and exceeding the upper limit on the number of defective tags.

[0045] If there are too many defects in the electrode rolls processed by the slitting equipment 400, the defects in the electrode rolls can be removed in the rewinding equipment 100. The electrode rolls with reduced defects (or no defects) can then be fed into the notching equipment 500. An excessive number of defects in the electrode rolls processed by the slitting equipment 400 may include exceeding the upper limit on the number of defective tags.

[0046] Here, each of the rewinding equipment 100 can be connected online. Each of the rewinding equipment 100 can be configured to discard defective electrodes from the electrode rolls and collect scrap data indicating the amount discarded. This allows for updating the amount of electrodes discarded in the rewinding equipment 100, thereby improving the traceability of the secondary battery manufacturing process.

[0047] Figure 2 shows a secondary battery manufacturing system 10 according to an exemplary embodiment.

[0048] Referring to Figure 2, the secondary battery manufacturing system 10 may include a rewinding machine 100, a server 1010, a server 1020, and a display device 1030.

[0049] The rewinding equipment 100 may include an unwinder 111, a rewinder 113, a splicing table 115, a scrap port 117, a first rotary encoder 121, a second rotary encoder 123, a reference point sensor 135, a first controller 141, and a second controller 143.

[0050] The secondary battery manufacturing system 10 can be configured to generate a roll map containing data on the electrode sheet ES. The roll map can represent the electrode sheet ES based on coordinate values ​​indicating its position on the electrode sheet ES. Processes for manufacturing a secondary battery can be performed on the electrode sheet ES, as described later. The roll map can represent the history of processes performed on the electrode sheet ES and can include data related to coordinates. This allows the roll map to enable feedback, feedforwarding, and tracking of the secondary battery manufacturing process, as described later.

[0051] The first electrode roll ER1, after the preceding process, can be loaded into an unwinder 111. The unwinder 111 can be configured to unwind the electrode sheet ES from the first electrode roll ER1. A rewinder 113 can be configured to wind the electrode sheet ES to form a second electrode roll ER2. The electrode sheet ES is wound onto the second electrode roll ER2 and can be cut and separated after reaching a predetermined winding length. This allows the electrode sheet ES to move between the unwinder 111 and the rewinder 113.

[0052] Roll maps can be generated in lot units. A lot is a production unit of a roll-to-roll process, and the separated second electrode roll ER2 is an example of a lot. Similarly, the first electrode roll ER1 newly loaded into the unwinder 111 is also an example of a lot. This allows the server 1020 to save the first roll map of the previous process (e.g., a coating process, a roll pressing process, or a slitting process). The first roll map can correspond to the first electrode roll ER1. The server 1020 can also be configured to generate a second roll map of the second electrode roll ER2 based on the processing of the rewinding equipment 100. The second roll map can correspond to the second electrode roll ER2.

[0053] As an unrestrictive example, the second roll map can be generated by loading the first roll map and updating the first roll map. Alternatively, the second roll map can be generated based on data generated at the rewinding equipment 100 without loading the first roll map.

[0054] Time-series data, structured according to the flow of time in the roll map (i.e., according to the progress of the process), can be associated with coordinate data based on the amount of movement of the electrode sheet ES (i.e., either consumption or input).

[0055] The manufacturing of secondary batteries involves a series of distinct processes, where the leading process influences the following process. In this context, it is difficult to reflect the time-series data of the leading process in the following process if it does not directly match the actual workpieces, intermediate products, and finished products in the real world. Below, we will refer to the correction of the following process based on data generated according to the results of the leading process as feedforward.

[0056] Here, "workpiece" refers to an article provided as a result of each process, such as an electrode sheet ES, which has undergone the coating, roll pressing, and slitting processes shown in Figure 1. "Semi-finished product" can refer to one of the following: a separation membrane cut by the notching process, an electrode, or an assembly thereof. A semi-finished product may also be a structure including a housing and an electrode assembly housed within the housing (in some cases, the structure further includes an electrolyte). "Product" refers to an article processed by the activation process to be operational as a secondary battery. The above definitions of workpiece, semi-finished product, and product relate to one aspect of them and do not preclude the usual definitions of them.

[0057] The electrode process for secondary batteries involves a series of roll-to-roll processes. For feedforwarding, time-series data needs to be associated with the positions of images of actual world workpieces, parts, semi-finished products, and finished products. Here, feedforwarding can include controlling the process for the electrode sheet ES based on a roll map of the first electrode roll ER1 generated in the previous process. The roll map can associate time-series data with coordinate data containing coordinate values ​​indicating the positions of images of actual world workpieces, parts, semi-finished products, and finished products. Based on the coordinate data, the roll map can provide a matching between time-series data and actual world workpieces, parts, semi-finished products, and finished products. Thus, the generation of roll maps and feedforwarding based on roll maps can achieve improved production efficiency and quality by quantifying and objectifying aspects of the process that were previously dependent on the arbitrary actions of the worker.

[0058] Furthermore, the roll map of a preceding lot can be used to improve the process for subsequent lots, and this action can be called process feedback. Process feedback using roll maps can include identifying process conditions and process parameters that cause problems and defects based on the data contained in the roll map. For example, the roll map of the first electrode roll ER1 processed in the current process may contain defective data DD, and in the rewinding equipment 100, the electrode sheet ES unwound from the first electrode roll ER1 can be discarded based on the defective data DD.

[0059] Furthermore, as described later, roll maps are generated cumulatively for the workpieces, parts, semi-finished products, and finished products of each unit process, enabling the tracking of process history for shipped products (e.g., battery cells, battery modules, or battery packs). For example, a battery cell may include a cell ID formed on the electrode assembly or case. The cell ID may include lot numbers and coordinate information for the electrodes and separators contained in the battery cell. In other words, the cell ID can be associated with the roll map of the electrodes and separators contained in the battery cell. This allows for the retrieval of historical manufacturing data for a battery cell based on its cell ID if an event such as a quality issue occurs in a battery cell that has already been shipped.

[0060] The first rotary encoder 121 can be configured to sense the amount of electrode sheet ES unwound from the first electrode roll ER1 by the unwinder 111. This allows the first rotary encoder 121 to generate an input amount signal UWAS indicating the length of the electrode sheet ES unwound by the unwinder 111. The first rotary encoder 121 can be configured to transmit the input amount signal UWAS to the first controller 141.

[0061] The second rotary encoder 123 can be configured to sense the amount of electrode sheet ES wound onto the second electrode roll ER2 by the rewinder 113. This allows the second rotary encoder 123 to generate a consumption signal WAS indicating the length of the electrode sheet ES wound onto by the rewinder 113. The second rotary encoder 123 can be configured to transmit the consumption signal WAS to the first controller 141.

[0062] A portion of the electrode sheet ES can be discarded, as described later. As a result, the length of the electrode sheet ES wound up by the unwinder 111 may differ from the amount of electrode sheet ES wound up by the rewinder 113.

[0063] The first controller 141 can be configured to collect coordinate data of the electrode sheet ES based on the consumption signal WAS and / or input signal UWAS of the electrode sheet ES. For example, the first controller 141 can determine the distance traveled by the electrode sheet ES based on the input signal UWAS of the electrode sheet ES, thereby enabling the first controller 141 to determine the position within the electrode sheet ES of the portion of the electrode sheet ES being unwound by the unwinder 111 at each point in time when an event occurs in the electrode sheet ES. As another example, the first controller 141 can determine the distance traveled by the electrode sheet ES based on the consumption signal WAS of the electrode sheet ES, thereby enabling the first controller 141 to determine the position within the electrode sheet ES of the portion of the electrode sheet ES being wound up by the rewinder 113 at each point in time when an event occurs in the electrode sheet ES. As yet another example, the first controller 141 can also determine the distance traveled by the electrode sheet ES based on the consumption signal WAS and the input signal UWAS, respectively.

[0064] The events here may include various processes, inspections, and measurements that occur on the electrode sheet ES in the rewinding equipment 100, such as cutting the electrode sheet ES, joining the electrode sheet ES, sensing reference points (datum points) on the electrode sheet ES, and sensing defective tags on the electrode sheet ES. The technical idea of ​​the present invention will be described below with reference to an embodiment in which the first controller 141 collects coordinate data based on the wear signal WAS of the electrode sheet ES, as a non-limiting example.

[0065] The coordinate data can include coordinate values ​​that match each part of the electrode sheet ES. That is, each of any points on the electrode sheet ES can be matched with a coordinate. The coordinate values ​​may be, but are not limited to, one-dimensional quantities in the longitudinal direction of the electrode sheet ES. The coordinate values ​​may also be two-dimensional quantities in the longitudinal direction and the Y direction in the width direction of the electrode sheet ES.

[0066] The NG sensor 131 can be configured to sense either an NG mark or an NG tag on the electrode sheet ES. The NG mark can be formed, for example, by an inkjet printer, and may contain information about the location and type of defect. The NG tag can be attached to the electrode sheet ES by an operator or an NG tag attacher. The NG tag can indicate the location of a defect on the electrode sheet ES. As a non-limiting example, the NG sensor 131 may be either a color sensor or a vision machine. The NG sensor 131 can be configured to generate an NG sensing signal NSS. The NG sensor 131 can be configured to transmit the NG sensing signal NSS to the first controller 141.

[0067] The first controller 141 can be configured to collect NG detection data NSD based on the NG detection signal NSS. The first controller 141 can be configured to associate the NG detection signal NSS with coordinate data in order to collect the NG detection data NSD. The NG detection data NSD may include, for example, a defect value indicating the presence or absence of a defect and the nature of the defect, and coordinate values ​​that are matched to the defect value.

[0068] To collect NG detection data NSD, the coordinate data can be calibrated based on the offset length OL1. Calibrating the coordinate data involves compensating for the difference between the portion of the electrode sheet ES sensed by the first rotary encoder 121, i.e., the portion of the electrode sheet ES wound up by the rewinder 113, and the portion of the electrode sheet ES sensed by the NG sensor 131.

[0069] According to an exemplary embodiment, the first controller 141 can collect NG detection data NSD by calibrating coordinate data collected at the same time as the NG detection signal NSS based on an offset length OL1, and associate the calibrated coordinate data with the NG detection signal NSS. The processing unit 131P can be configured to transmit the NG detection data NSD to the first controller 141.

[0070] The offset length OL1 is the length of the electrode sheet ES between the NG sensor 131 and the rewinder 113, according to the movement path of the electrode sheet ES. The offset length OL1 may be the same as the straight-line distance between the NG sensor 131 and the rewinder 113, or it may be longer than the straight-line distance between the NG sensor 131 and the rewinder 113.

[0071] The second controller 143 can be configured to control the operation of the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119. The second controller 143 can be configured to generate signals for the operation and interruption of the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119. The signals for the operation and interruption of the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119 can be generated based on a body containing product ID and manufacturing recipe details.

[0072] The second controller 143 can be configured to receive NG detection data NSD from the first controller 141. The second controller 143 can be configured to receive fault data DD from the server 1020. The fault data DD can be loaded into the second controller 143 via the server 1010. Here, the fault data DD can indicate the location of a fault on the first electrode roll ER1. The fault data DD can be included in the first roll map of the first electrode roll ER1.

[0073] The second controller 143 can be configured to generate signals for the operation and interruption of the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119 based on the NG detection data NSD and fault data DD. When a fault on the electrode sheet ES identified by the fault data DD and NG detection data NSD approaches the splicing table 115, the second controller 143 can be configured to generate signals to slow down the movement speed of the electrode sheet ES or to interrupt the winding and unwinding of the unwinder 111 and rewinder 113.

[0074] After cutting the defective starting position (or a position adjacent to the defective starting position, taking process margins into consideration) on the splicing table 115, the scrap port 117 can be configured to wind up the defective portion DES of the electrode sheet ES, as shown by the thick dashed line. After the defective portion DES of the electrode sheet ES has been sufficiently wound up by the scrap port 117, the electrode sheet ES connected to the scrap port 117 and the electrode sheet ES connected to the unwinder 111 can be separated. The current process can then be continued by splicing together the portion of the electrode sheet ES connected to the unwinder 111 and the portion of the electrode sheet ES connected to the rewinder 113. The portion of the electrode sheet ES connected to the unwinder 111 and the portion of the electrode sheet ES connected to the rewinder 113 can be spliced ​​together on the splicing table 115.

[0075] Conventionally, there were problems such as defective electrode sheets being wound up without being discarded, or defective portions remaining on the electrode sheet even after discarding. According to the exemplary embodiment, the defective portion DES of the electrode sheet ES is discarded based on NG detection data NSD and defective data DD, thereby improving the reliability and traceability of the discarding of the electrode sheet ES.

[0076] To discard the defective portion DES of the electrode sheet ES, after the unwinder 111 and rewinder 113 have been interrupted, the defective portion DES of the electrode sheet ES can be moved to the scrap port by the drive of the unwinder 111 without the drive of the rewinder 113. The first controller 141 may be configured to collect scrap data SD based on the unwind amount signal UWAS after the discarding of the defective portion DES of the electrode sheet ES has begun. In order to collect scrap data SD, the first controller 141 may also receive signals from the second controller 143 to control the operation of the unwinder 111 and rewinder 113. As another example, the first controller 141 may also be configured to collect scrap data SD based on the amount of rotation of the drive roll of the scrap port 117. As yet another example, the first controller 141 may also be configured to collect scrap data SD based on the change in distance between reference points on the electrode sheet ES and the distance between the seam and the reference point on the electrode sheet ES.

[0077] Conventionally, the amount of electrode sheets to be discarded was determined subjectively by the worker or based on the weight of the discarded portion of the electrode sheet, resulting in low accuracy in determining the amount of electrode sheets to be discarded and thus reduced process traceability. According to an exemplary embodiment, the discard process, which was previously dependent on the worker's subjectivity, can be made objectivized by collecting scrap data SD that shows the location and amount of the discarded electrode sheet portion DE based on the input amount signal UWAS. This can improve the reliability and traceability of secondary battery manufacturing.

[0078] The seam sensor 133 can be configured to sense seams on the electrode sheet ES to generate a seam detection signal JSS. The seam allows the electrode sheet ES to be joined together after the discarding of the defective portion DES of the electrode sheet ES. As a non-limiting example, the seam sensor 133 may be either a color sensor or a vision machine. The seam sensor 133 can be configured to transmit the seam detection signal JSS to the first controller 141.

[0079] The first controller 141 can be configured to collect seam detection data JSD based on the seam detection signal JSS. The first controller 141 can be configured to collect seam detection data JSD by associating the seam detection signal JSS with coordinate data.

[0080] According to an exemplary embodiment, the first controller 141 can collect seam detection data JSD by calibrating coordinate data collected at the same time as the seam detection signal JSS based on an offset length OL2, and associate the calibrated coordinate data with the seam detection signal JSS.

[0081] The offset length OL2 is the length of the electrode sheet ES between the seam sensor 133 and the rewinder 113, according to the movement path of the electrode sheet ES. The offset length OL2 may be the same as the straight-line distance between the seam sensor 133 and the rewinder 113, or it may be longer than the straight-line distance between the seam sensor 133 and the rewinder 113.

[0082] The reference point sensor 135 can be configured to sense reference points on the electrode sheet ES to generate a reference point sensing signal DSS. The reference points can be formed at set intervals on the electrode sheet ES to indicate their position on the electrode sheet ES. Each of the reference points may be, for example, a two-dimensional barcode containing information about the order in which they were formed. Thus, the reference point sensing signal DSS can include a time value and a reference point order value corresponding to the sensing of the reference point. The reference point sensor 135 can be configured to transmit the reference point sensing signal DSS to the first controller 141.

[0083] The first controller 141 can be configured to collect reference point sensing data DSD based on a reference point sensing signal DSS. The first controller 141 can be configured to collect reference point sensing data DSD by associating the reference point sensing signal DSS with coordinate data.

[0084] According to an exemplary embodiment, the first controller 141 can calibrate coordinate data collected at the same time as the reference point sensing signal DSS based on an offset length OL3 in order to collect reference point sensing data DSD, and associate the calibrated coordinate data with the reference point sensing signal DSS.

[0085] The offset length OL3 is the length of the electrode sheet ES between the reference point sensor 135 and the rewinder 113, according to the movement path of the electrode sheet ES. The offset length OL3 may be the same as the straight-line distance between the reference point sensor 135 and the rewinder 113, or it may be longer than the straight-line distance between the reference point sensor 135 and the rewinder 113.

[0086] According to an exemplary embodiment, any data generated based on scrap data SD, NG sensing data NSD, and events on electrode sheet ES can be calibrated based on reference point sensing data DSD.

[0087] The rewinding equipment 100 may further include additional measuring instruments and inspection instruments. Each of the measuring instruments and inspection instruments may include a sensing unit and a processing unit. The measuring instruments may be configured to generate measurement data, and the inspection instruments may be configured to generate inspection data. The processing units of the inspection instruments and measuring instruments may be connected by wire or wirelessly to the sensing unit of the inspection instrument and the sensing unit of the measuring instrument.

[0088] The measurement data may include multiple numerically represented measurement values. For example, the measurement data may include dimensional data of the electrode sheet ES such as thickness and width, loading amount data of the coating material on the electrode sheet ES, dimensional data such as the width of the insulating material provided on the coating material and the overlap width between the coating material and the insulating material, and mismatch data between the surface lane on the upper surface of the electrode sheet ES and the surface lane on the lower surface of the electrode sheet ES. Here, the loading amount represents the amount of coating material loaded per unit area of ​​the electrode sheet ES and may be the area density of the coating material.

[0089] The inspection data collected by the inspection device may include quality judgments and process events related to a portion of the electrode sheet ES. For example, the inspection data may include visual data of the electrode sheet ES collected by an image-based inspection device such as a vision machine, data on breaks and seams of the electrode sheet ES, data on the portion of the electrode sheet ES that has been sampled, data on the portion of the electrode sheet ES scheduled for disposal, data on the discarded portion of the electrode sheet ES, data on the quality of the coating and insulating materials on the electrode sheet ES, data on reference points indicating the location of the electrode sheet ES, and defect data such as pinhole defects, crater defects, line defects, crack defects, side ring defects, island defects, fold defects, wrinkle defects, puncture defects, and indentation defects. Reference points may be formed at predetermined intervals on the electrode sheet ES, and the location of other elements on the electrode sheet ES may be known based on the reference points. The inspection device may be any one of a color sensor, a seam sensor, a reference point sensor, and a vision machine.

[0090] The measurement and inspection data described above may be time-series data. Temporal ordering is a key characteristic of time-series data, where events are organized in the order in which they occur and arrive for processing. That is, measurement and inspection data can be stored based on the time at which the measurement and inspection were performed, and thus can be associated with time. This allows each measurement value in the measurement data to be time-matched, and each inspection value in the inspection data to be time-matched.

[0091] As an example, measurement data (e.g., loading amount on electrode sheet ES or thickness of electrode sheet ES) may have a series of measurement values ​​and time values ​​associated with the series of measurement values. The measurement values ​​and time values ​​may, but are not limited to, a one-to-one matching. As another example, defect data may have values ​​indicating a defect and time values ​​associated with the values ​​indicating a defect. Here, indicating a defect means including information about at least one of the following: the presence or absence of a defect and the type of defect.

[0092] The measurement data is processed according to a set method to determine whether the measured portion of the electrode sheet ES is good or bad. If the measured amount of coating material on the electrode sheet ES (e.g., the loading amount on the electrode sheet ES or the thickness of the electrode sheet ES) is within a set range including upper and lower limits, the corresponding portion of the electrode sheet ES can be determined to be good. If the measured amount of coating material on the electrode sheet ES (e.g., the loading amount on the electrode sheet ES or the thickness of the electrode sheet ES) is less than the lower limit or greater than the upper limit, the corresponding portion of the electrode sheet ES can be determined to be defective.

[0093] The sensing unit of the inspection and measuring instrument may be configured to sense physical quantities of the electrode sheet ES in order to generate a measurement signal. For example, the sensing unit may include a TDI (Time Delay and Integration) camera, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and a TOF (Time of Flight) sensor. The sensing unit may also include an emitter and receiver configured to perform measurements using non-destructive signals such as ultrasound, microwaves, terahertz waves, and infrared light. The sensing unit may also include analog and / or digital sensors such as biosensors, chemical sensors, composition sensors, current and / or power meters, air quality sensors, gas sensors, Hall effect sensors, brightness level sensors, and light sensors. The measuring instrument may also include pressure sensors, temperature sensors, ultrasonic sensors, proximity sensors, door condition sensors, motion tracking sensors, humidity sensors, color sensors, OCR readers, visible light sensors, infrared sensors, and cameras.

[0094] The processing unit can be configured to collect inspection and measurement signals sensed by the sensing unit in order to generate inspection and measurement data. The processing unit can be connected to the sensing unit by wire or wireless connection. The processing unit of the measuring instrument can be configured to calibrate the measurement data by adding an offset measurement to each of the multiple measurement values ​​in the measurement data. Due to process progression and equipment aging, the measurement values ​​in the measurement data may differ from the actual values. The processing unit can correct the measurement data based on the offset measurement. The offset measurement can be determined based on known information about the equipment system by methods such as sample testing.

[0095] According to exemplary embodiments, the inspection and measuring instruments can be configured to calibrate coordinate data based on their respective positions. More specifically, the inspection and measuring instruments can be configured to associate the coordinate values ​​of the coordinate data with the measured values ​​of the measurement data or the inspected values ​​of the inspection data by calibrating the coordinate data based on offset lengths. The calibration of coordinate data by the inspection and measuring instruments is similar to calibration using offset lengths OL1, OL2, and OL3.

[0096] The processing unit of the measuring instrument can be configured to collect evaluation data based on the measurement data. The evaluation data can be collected based on a comparison of the measured values ​​in multiple intervals within the electrode sheet ES with a set range. For example, measured values ​​(or averages) within a first range can be determined to be normal, measured values ​​(or averages) within a second range that is larger than the first range can be determined to be excessive, measured values ​​(or averages) within a third range that is larger than the second range can be determined to be very excessive, measured values ​​(or averages) within a fourth range that is smaller than the first range can be determined to be insufficient, and measured values ​​(or averages) within a fifth range that is even smaller than the fourth range can be determined to be very insufficient.

[0097] Here, if the lower limit of the second range is greater than or equal to the upper limit of the first range, then the second range is greater than the first range. Similarly, if the upper limit of the fourth range is less than or equal to the lower limit of the first range, then the fourth range is less than the first range.

[0098] The first controller 141 may be in operative communication with the first rotary encoder 121, the second rotary encoder 123, the NG sensor 131, the seam sensor 133, the reference point sensor 135, additional measuring instruments, and additional inspection instruments via a wired or wireless data network. The data network may be unidirectional or bidirectional. The data network may be embodied by a public network and / or specialized network using a physical channel, WiFi, Bluetooth®, and / or other frequency bands. The first rotary encoder 121, the second rotary encoder 123, the NG sensor 131, the seam sensor 133, the reference point sensor 135, additional measuring instruments, and additional inspection instruments may be configured to collect data from equipment, workpieces, semi-finished products, and finished products within the rewinding equipment 100, or to generate signals for collecting data.

[0099] The first controller 141 can be configured to transmit NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD to the second controller 143. The NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD can be transmitted to the first server 1020 via the second controller 143 and server 1010. The second controller 143 and server 1010 can relay data communication, including the NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD, between the first server 1020 and the first controller 141. However, it is not limited thereto, and the first controller 141 can also transmit the NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD directly to server 1020.

[0100] To control the process, a communication line can be installed between the second controller 143 and the server 1020, connecting the second controller 143 and the server 1020 via the server 1010. This allows for data transmission via the second controller 143 to save resources required for installing a communication line, compared to the case where the first rotary encoder 121, the second rotary encoder 123, and the reference point sensor 135 directly transmit input amount signal UWAS, consumption amount signal WAS, and measurement signal to the server 1020, compared to the case where the first controller 141 directly transmits measurement data CMD and evaluation data ED to the server 1020, thereby streamlining data processing and management.

[0101] Server 1010 may be a communication server. Server 1010 may include a program for communication between the second controller 143 of the manufacturing equipment and the higher-level server, Server 1020. Server 1010 may also be embodied in hardware, as described later. The language and protocol of Server 1020 may differ from those of the second controller 143. For example, the language of Server 1020 may be SQL, and the language of the second controller 143 may be a ladder diagram.

[0102] Server 1020 can be configured to generate a roll map based on NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD. The roll map can be generated on a lot basis. The roll map can include data on lot specifications. Lot specifications may include, for example, lot number, length of wound electrode sheet ES, width of electrode sheet ES, and material and composition used to process the electrode sheet ES.

[0103] According to an exemplary embodiment, the server 1020 may be a data processing system that supports various activities necessary to manage the manufacturing of secondary batteries, such as work schedule management, work instructions, quality control, and work performance aggregation. The server 1020 may be, for example, a Manufacturing Execution System (MES). The server 1020 may be configured to input, process, output, and communicate data necessary for electrode manufacturing, such as coating processes, pressing processes, and manufacturing processes.

[0104] According to another exemplary embodiment, the server 1020 may be configured to store and process raw measurement data. The server 1020 can manage the quality of electrode sheet ES processing by continuously monitoring the processing of electrode sheet ES based on the measurement data. According to an exemplary embodiment, the server 1020 may be a Statistical Process Controller (SPC). The server 1020 can identify problem conditions in a timely manner and provide alarms to operators before potential problems occur by collecting and analyzing manufacturing data in near real time.

[0105] According to other exemplary embodiments, the server 1020 may be, for example, a data warehouse that can store NG detection data NSD, scrap data SD, and coordinate data for a long period of time based on the product quality assurance period, etc.

[0106] According to other exemplary embodiments, server 1020 may also be provided separately from the MES, SPC, and data warehouse for creating role maps.

[0107] The first controller 141 and the second controller 143 may be PLCs (Programmable Logic Controllers). A PLC is a special form of microprocessor-based controller that uses programmable memory to store instructions and controls machines and processes by embodying functions such as logic, sequencing, timing, counting, and arithmetic. PLCs are easy to operate and program.

[0108] Servers 1010 and 1020 can be embodied in hardware, firmware, software, or a combination thereof. For example, Servers 1010 and 1020 can include computing devices such as workstation computers, desktop computers, laptop computers, and tablet computers. Servers 1010 and 1020 can also include any one of the following: a simple controller, a microprocessor, a complex processor such as a CPU or GPU, a software-based processor, dedicated hardware, and firmware. Servers 1010 and 1020 can be embodied, for example, in general-purpose computers or application-specific hardware such as DSPs (Digital Signal Processors), FPGAs (Field Programmable Gate Arrays), and ASICs (Application Specific Integrated Circuits).

[0109] Server 1020 may include a physical server or a cloud server. Server 1020 can provide data and analysis results to workers through various frameworks. The framework may include protocols that support data transmission so that the display device 1030 can visualize the data through a user interface and provide updated visualizations when new data is calculated by Server 1020. The protocols that support the above data transmission may use HTML, JavaScript, and / or JSON.

[0110] Server 1020 can include a variety of APIs (Application Programming Interfaces) for storing data in databases and other data management tools. These APIs can also be used to retrieve data in the databases of various data management systems. These data management systems can provide access to the database, pull data from it, retrieve data, and generate metrics. Here, metrics are tools for visualizing data. Metrics include time-series generated measurements and can be used for application monitoring and generating status alerts.

[0111] The server 1020 can transmit visualization commands VC to the display device 1030, and the display device 1030 can visualize the role map and display the visualized role map.

[0112] The rewinding equipment 100 can embody a plug-in architecture along with an API for data acquisition to provide plug-and-play connectivity for measuring and testing instruments. This allows resources at specific process steps and sites to be easily transferred to other processes and sites, or new resources to be easily introduced at each process step and site.

[0113] The data network between elements of the secondary battery manufacturing system 10 can include a variety of communication channels, including unidirectional, bidirectional wired, and wireless communication. For example, the data network can include industrial protocol networks such as OPC, Modbus, and ProfiNet. The communication channel may be dedicated conduit communication such as USB (Universal Serial Bus), IEEE 802 (Ethernet), IEEE 1394 (FireWire), or other high-speed data communication standards.

[0114] In some embodiments, the secondary battery manufacturing system 10 may further include a manual input system that allows an operator to input manufacturing data. The secondary battery manufacturing system 10 may allow operator data input using an input tool and computer-based input of manufacturing data, such as Excel file scraping. The manual input system may be, for example, a Human-Machine Interface (HMI) of a Supervisory Control and Data Acquisition (SCADA) system. SCADA systems generally include a combination of software and hardware such as a PLC and Remote Terminal Units (RTUs). An HMI is a screen that facilitates communication between the operator and the SCADA system and is a key component of the SCADA system. For example, manual input via an HMI may include the selection of defect types and the reflection of performance at completion.

[0115] According to some embodiments, the operation of the first controller 141, the second controller 143, the server 1010, and the server 1020 can be embodied as instructions stored on a machine-readable medium that can be read and executed by one or more processors. Here, the machine-readable medium may include any mechanism for storing and / or transmitting information in a form readable by a machine (e.g., a computing device). For example, the machine-readable medium may include ROM (Read Only Memory), RAM (Random Access Memory), magnetic disk storage medium, optical storage medium, flash memory, electrical, optical, acoustic or other forms of radio signals (e.g., carrier waves, infrared signals, digital signals, etc.) and any other signals.

[0116] The first controller 141, the second controller 143, the server 1010, and the server 1020 may consist of firmware, software, routines, and instructions for performing the operations described above or any of the processes described below. For example, the first controller 141, the second controller 143, the server 1010, and the server 1020 may be instantiated in memory.

[0117] The first controller 141 can be embodied by software configured to receive input amount signal UWAS, consumption amount signal WAS, NG detection signal NSS, seam detection signal JSS, and reference point detection signal DSS, collect coordinate data, NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD, and transmit NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD.

[0118] The second controller 143 can be embodied by software configured to generate control signals for controlling the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119 based on product ID, product recipe, defective data DD, and NG detection signal NSS, and to receive and transmit NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD.

[0119] Server 1010 can be represented by software for relaying data and information transmission between the second controller 143 and server 1020. More specifically, server 1010 can be represented by software configured to perform flow control, error control, synchronization, sequence control, addressing, multiplexing, routing, and format conversion of communications between the second controller 143 and server 1020.

[0120] The server 1020 can be embodied by software configured to transmit product ID and product recipe to the second controller 143 and generate a roll map based on NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD.

[0121] However, this is for illustrative purposes only, and the operation of the first controller 141, the second controller 143, the server 1010, and the server 1020 described above can also be triggered by other devices that execute computing devices, distributed computing devices, processors, firmware, software, routines, and instructions, etc.

[0122] The architecture of the secondary battery manufacturing system 10, configured to generate a role map, can be realized by adding only a first controller 141 to the processing unit, second controller 143, server 1010, and server 1020, which are essential elements of a modern process control system. In other words, the system according to the exemplary embodiment can utilize resources already installed in the manufacturing site and save additional capital expenditures. Furthermore, by applying the same architecture as existing manufacturing equipment to newly constructed manufacturing equipment, the reliability of secondary battery manufacturing, the detection and improvement of problematic processes, and the introduction of new processes can be made more efficient.

[0123] (Second Embodiment) Figure 3 shows a secondary battery manufacturing system 11 according to an exemplary embodiment.

[0124] Referring to Figure 3, the secondary battery manufacturing system 11 may include a rewinding machine 101, a server 1010, a server 1020, and a display device 1030.

[0125] Servers 1010, 1020, and 1030 are substantially the same as those described with reference to Figure 2.

[0126] The rewinding equipment 101 may include an unwinder 111, a rewinder 113, a splicing table 115, a scrap port 117, a first rotary encoder 121, a second rotary encoder 123, a reference point sensor 135, an integrated controller 140, a server 1010, a server 1020, and a display device 1030.

[0127] The unwinder 111, rewinder 113, splicing table 115, scrap port 117, first rotary encoder 121, second rotary encoder 123, reference point sensor 135, server 1010, server 1020, and display device 1030 are substantially the same as those described with reference to Figure 1, so their redundant descriptions are omitted.

[0128] The integrated controller 140 can be configured to perform the functions of the first controller 141 and the second controller 143 in Figure 1. Thus, the integrated controller 140 can be embodied by software configured to receive input amount signal UWAS, consumption amount signal WAS, NG detection signal NSS, seam detection signal JSS, and reference point detection signal DSS; collect coordinate data, NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD; transmit NG detection data NSD, seam detection data JSD, scrap data SD, and reference point detection data DSD; and generate control signals to control the unwinder 111, rewinder 113, scrap port 117, and processing equipment 119 based on product ID, product recipe, defective data DD, and NG detection signal NSS.

[0129] The present invention has been described in more detail above through the drawings and embodiments. However, the configurations described in the drawings or embodiments described herein are merely one embodiment of the present invention and do not represent the entire technical concept of the present invention. Therefore, there may be various equivalents and modifications that can be substituted for them at the time of filing. [Explanation of symbols]

[0130] 10. Secondary battery manufacturing system 11. Secondary battery manufacturing system 111 Unwinder 113 Rewinder 115 Splicing Table 117 Scrapport 119 Processing equipment 121 First Rotary Encoder 123 Second Rotary Encoder 131 NG sensor 131P Processing Unit 133 Seam sensor 135 Reference Point Sensor 140 controllers 141 First Controller 143 Second Controller 1010 Server 1020 Server 1 1030 Display device

Claims

1. An unwinder configured to unwind an electrode sheet from the first electrode roll, A scrap port configured to dispose of defective portions of the electrode sheet, A rewinder configured to wind the electrode sheet onto a second electrode roll, A first rotary encoder configured to sense the length of the electrode sheet unwound by the unwinder in order to generate an input amount signal, A second rotary encoder configured to sense the length of the electrode sheet wound up by the rewinder in order to generate a consumption signal, A rewinding apparatus comprising: a first controller configured to collect coordinate data indicating the position on the electrode sheet based on the consumption signal.

2. The rewinding apparatus according to claim 1, wherein the first controller is configured to collect scrap data indicating the length of the discarded portion of the electrode sheet based on the input signal.

3. The rewinding apparatus according to claim 1 or 2, further comprising an NG sensor configured to sense NG marks and NG tags on the electrode sheet in order to generate an NG detection signal.

4. The rewinding apparatus according to claim 3, wherein the first controller is configured to collect NG detection data by associating the NG detection signal with the coordinate data.

5. The rewinding apparatus according to claim 4, wherein the first controller is configured to control the unwinder and the rewinder based on the NG detection data.

6. The rewinding apparatus according to claim 4, further comprising a second controller configured to control the unwinder and the rewinder based on the NG detection data.

7. The rewinding apparatus according to claim 1 or 2, further comprising a seam sensor configured to sense seams in the electrode sheets in order to generate a seam sensing signal.

8. The rewinding apparatus according to claim 7, wherein the first controller is configured to collect seam detection data by associating the seam detection signal with the coordinate data.

9. The rewinding apparatus according to claim 1 or 2, further comprising a reference point sensor configured to sense a reference point on the electrode sheet in order to generate a reference point sensing signal.

10. The rewinding apparatus according to claim 9, wherein the first controller is configured to collect reference point sensing data by associating the reference point sensing signal with the coordinate data.

11. The first controller is configured to transmit the reference point sensing data to the server. The rewinding apparatus according to claim 10, wherein the server is configured to generate a roll map representing the electrode sheet based on the reference point sensing data.

12. The first controller is configured to transmit the reference point sensing data to the second controller. The rewinding apparatus according to claim 10, wherein the second controller is configured to control the unwinder and the rewinder.

13. The second controller is configured to transmit the reference point sensing data to the server. The rewinding apparatus according to claim 12, wherein the server is configured to generate a roll map representing the electrode sheet based on the reference point sensing data.

14. A roll pressing facility configured to perform a rolling process, The equipment includes a rewinding system configured to process the first electrode roll processed by the roll pressing equipment, A secondary battery manufacturing system comprising: an unwinder configured to unwind an electrode sheet from a first electrode roll; a scrap port configured to discard defective portions of the electrode sheet; a rewinder configured to wind the electrode sheet onto a second electrode roll; a first rotary encoder configured to sense the length of the electrode sheet unwound by the unwinder in order to generate an input signal; a second rotary encoder configured to sense the length of the electrode sheet wound up by the rewinder in order to generate a consumption signal; and a first controller configured to collect coordinate data indicating the position on the electrode sheet based on the consumption signal.

15. The secondary battery manufacturing system according to claim 14, wherein the first controller is configured to collect scrap data indicating the length of the discarded portion of the electrode sheet based on the input signal.

16. The secondary battery manufacturing system according to claim 14, further comprising an NG sensor configured to sense NG marks and NG tags on the electrode sheet in order to generate an NG detection signal.

17. The secondary battery manufacturing system according to claim 16, wherein the first controller is configured to collect NG detection data by associating the NG detection signal with the coordinate data.

18. The secondary battery manufacturing system according to claim 17, wherein the first controller is configured to control the unwinder and the rewinder based on the NG detection data.

19. The secondary battery manufacturing system according to claim 17, further comprising a second controller configured to control the unwinder and the rewinder based on the NG detection data.

Images