Method and apparatus for cleaning electrodes on rolling mill rolls

Abstract

A method for automatically cleaning a mill roll used in an electrode rolling process according to one embodiment of the present invention includes a step of determining whether the mill roll is in an out-of-operation state, and if the mill roll is in an out-of-operation state, a step of cleaning the mill roll in a first cleaning mode, wherein the first cleaning mode is a mode in which cleaning of the mill roll is performed while a process of rolling an electrode with the mill roll is stopped.

Description

Technical Field

[0005] , ,

[0006] , ,

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0125135 filed on September 30, 2022, and Korean Patent Application No. 10 - 2023 - 0127648 filed on September 25, 2023, and all the contents disclosed in the documents of the Korean patent applications are included as part of this specification.

[0002] The present invention relates to a method and an apparatus for cleaning a rolling roll used in an electrode manufacturing process, specifically, to a rolling roll cleaning method and an apparatus for automatically cleaning a rolling roll during operation and non - operation of the rolling roll, respectively.

Background Art

[0003] Due to the depletion of fossil fuels, the price of energy sources has increased, the concern about environmental pollution has been amplified, and the demand for eco - friendly alternative energy sources has become an essential factor for future life. In particular, with the development of technology and the increasing demand for mobile devices, the demand for secondary batteries as an energy source has been rapidly increasing.

[0004] Typically, in terms of the shape of the battery, there is a high demand for rectangular secondary batteries and pouch - type secondary batteries that are thin and applicable to mobile phones, etc. In terms of materials, there is a high demand for lithium secondary batteries such as lithium - ion batteries and lithium - ion polymer batteries with high energy density, discharge voltage, and output stability.

[0005] Generally, a secondary battery is manufactured by applying an electrode mixture layer containing an electrode active material on the surface of a current collector to form a positive electrode and a negative electrode, creating an electrode assembly with a separator interposed therebetween, and then installing it inside a cylindrical or rectangular metal can or a pouch - type case made of an aluminum laminate sheet, and mainly injecting or impregnating the electrode assembly with a liquid electrolyte or using a solid electrolyte.

[0006] Furthermore, secondary batteries can also be classified according to the structure of their electrode assemblies, which consist of a positive electrode / separating membrane / negative electrode. Typical examples include jelly-roll (wind-up type) electrode assemblies, which have a structure in which long sheet-like positive and negative electrodes are wound up with a separating membrane in between; stack-type (laminated type) electrode assemblies, which have multiple positive and negative electrodes cut into predetermined units and sequentially stacked with a separating membrane in between; and stack / foldable electrode assemblies, which have a structure in which a bi-cell or full cell, in which positive and negative electrodes of predetermined units are stacked with a separating membrane in between, is wound up with a separating membrane sheet.

[0007] On the other hand, electrodes generate electric current through ion exchange, and the positive and negative electrodes that make up the electrodes are constructed by coating an electrode active material onto an electrode current collector made of metal.

[0008] The separation membrane is positioned between the positive and negative electrodes of the battery to provide insulation, maintain the electrolyte, and provide a pathway for ion conduction.

[0009] The roll rolling process, slitting process, notching process, lamination process, or folding process for manufacturing the aforementioned electrodes and separation membranes mostly utilizes roll-to-roll processing, where roll-to-roll processing refers to a process in which multiple bendable metal foils move between rollers while coating, printing, and other processes are carried out.

[0010] Specifically, one method involves unwinding a roll that is winding a flexible, thin sheet-like material, supplying the material, performing coating or printing on the supplied material, and then winding the processed material back onto another roll for recovery. In particular, the positive and negative electrodes for secondary batteries are constructed by coating a positive electrode active material or a negative electrode active material onto a sheet and then rolling it.

[0011] In such rolling processes, repeated rolling is performed, and if active material or other foreign matter remaining after rolling adheres to the rolls during rolling, this foreign matter can adhere to the electrodes during subsequent rolling processes, reducing the quality of the electrodes and the batteries containing them. Therefore, rolling roll cleaning equipment is used to remove contamination from the rolling rolls.

[0012] In contrast, conventional rolling mill roll cleaning equipment has employed a method in which, while the rolling mill rolls are driven for electrode manufacturing, a cleaning solution is sprayed through a nozzle onto cleaning parts such as cleaning rollers, and the rolling mill rolls are cleaned in the cleaning parts where the cleaning solution has been sprayed.

[0013] Nevertheless, if contaminants are present on the surface of the rolling mill rolls, the rolling mill's operation is stopped, and workers use wipers or other means to remove the contaminants from the surface of the rolling mill rolls. This reduces the production efficiency of electrode manufacturing.

[0014] On the other hand, when cleaning the rolling rolls during the electrode manufacturing process while the rolling rolls are in motion, there are limitations on the type and amount of cleaning solution used to maintain the amount of residual moisture in the electrodes. For this reason, oil-based cleaning solutions containing oil components are mainly used.

[0015] However, when using such oil-based cleaning solutions, there were limitations to the removal of contaminants. For example, in the case of a negative electrode rolling roll used to roll the negative electrode of a secondary battery, the solvent for the negative electrode is water, so there were limitations to removing contaminants from the negative electrode rolling roll using only the oil component. As a result, contaminants were not completely removed and tended to remain. When rolling electrodes using rolling rolls with residual contaminants in this state, the contaminants on the rolling roll surface caused traces on the electrode surface, leading to problems such as electrode detachment.

[0016] Therefore, in order to solve these problems, methods and apparatus for more efficient cleaning of rolling mill rolls are needed. [Overview of the project] [Problems that the invention aims to solve]

[0017] The present invention relates to a method and apparatus for more efficiently cleaning rolling rolls used in an electrode manufacturing process, and aims to provide a method and apparatus for automatically cleaning the rolling rolls while also cleaning the rolling rolls even when they are not in operation.

[0018] However, the problems that the embodiments of the present invention aim to solve are not limited to those described above, and can be extended in various ways within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0019] A method for automatically cleaning rolling rolls used in an electrode rolling process according to one embodiment of the present invention includes the steps of determining whether the rolling rolls are in a non-operating state, and, if the rolling rolls are in a non-operating state, cleaning the rolling rolls in a first cleaning mode, wherein the first cleaning mode is one in which the cleaning of the rolling rolls is performed while the process of rolling electrodes with the rolling rolls is stopped.

[0020] If the rolling rolls are in operation, the process further includes cleaning the rolling rolls in a second cleaning mode, the second cleaning mode may be a process in which the rolling rolls are cleaned at the same time as the process of rolling electrodes with the rolling rolls is performed.

[0021] In each of the first and second washing modes, at least one of the following may differ: the type of cleaning solution, the number of times and amount of cleaning solution supplied, and the speed at which the cleaning cloth moves.

[0022] The step of determining whether the rolling roll is in a non-operating state may include receiving an input of the rotational speed of the rolling roll, counting the waiting time of the rolling roll if the rotational speed of the rolling roll is 0, and determining that the rolling roll is in a non-operating state if a first predetermined time has elapsed while the rotational speed of the rolling roll is 0.

[0023] The step of determining whether the rolling roll is in a non-operating state may include receiving input of the position of the rolling roll, counting the waiting time of the rolling roll if the rolling roll is in a predetermined waiting position, and determining that the rolling roll is in a non-operating state if a second predetermined time has elapsed while the rolling roll is in the predetermined waiting position.

[0024] The step of determining whether the rolling roll is in a non-operating state may include receiving inputs for the rotational speed and position of the rolling roll, respectively; counting the waiting time of the rolling roll if the rotational speed of the rolling roll is 0; counting the waiting time of the rolling roll if the rolling roll is in a predetermined waiting position; and determining that the rolling roll is in a non-operating state if a first predetermined time has elapsed while the rotational speed of the rolling roll is 0 and a second predetermined time has elapsed while the rolling roll is in a predetermined waiting position.

[0025] The step of cleaning the rolling roll in a first cleaning mode may include the step of measuring the brightness value of the surface of the rolling roll, and, if the brightness value of the surface of the rolling roll is less than or equal to a first predetermined brightness value, the step of cleaning the rolling roll for a third predetermined time.

[0026] The step of cleaning the rolling roll in the first cleaning mode further includes measuring the brightness value of the surface of the cleaned rolling roll and determining whether the brightness value is greater than or equal to a second predetermined brightness value. When the brightness value of the surface of the rolling roll is greater than or equal to the second predetermined brightness value, the step of cleaning in the first cleaning mode can be automatically terminated.

[0027] The step of cleaning the rolling roll in the first cleaning mode further includes measuring the brightness value of the surface of the cleaned rolling roll and determining whether the brightness value is greater than or equal to a second predetermined brightness value. When the brightness value of the surface of the rolling roll is less than the second predetermined brightness value, the step of cleaning the rolling roll over the third predetermined time can be repeated.

[0028] The third predetermined time may be a time selected from any of 3 minutes to 10 minutes.

[0029] The second predetermined brightness value may be greater than the first predetermined brightness value.

[0030] The first predetermined brightness value may be 40%, and the second predetermined brightness value may be 80%.

[0031] The number of times and the amount of the cleaning liquid supplied in the first cleaning mode may be more than the number of times and the amount of the cleaning liquid supplied in the second cleaning mode.

[0032] The cleaning liquid provided in the first cleaning mode may be an oil-based cleaning agent.

[0033] The cleaning liquid provided in the first cleaning mode may be selected from any of water, acetone, an aqueous cleaning liquid, or at least two combinations selected therefrom.

[0034] The cleaning liquid provided in the second cleaning mode may be an oil-based cleaning agent.

[0035] An apparatus for automatically cleaning a rolling roll to perform the method according to the above-described embodiment may include a sensor unit for measuring the brightness value of the surface of the rolling roll, a cleaning fluid supply unit for supplying the cleaning fluid to the rolling roll, a cleaning unit for cleaning the surface of the rolling roll, and a control unit that receives data input from the sensor unit and controls whether or not the cleaning fluid supply unit and the cleaning unit are operating.

[0036] The cleaning fluid supply unit is provided in multiple units, some of which supply an oil-based cleaning agent, and the remaining units which supply water, acetone, an aqueous cleaning solution, or at least two combinations selected from these.

[0037] The cleaning device may consist of multiple devices, some of which are for the first cleaning mode and the remaining devices may be for the second cleaning mode. [Effects of the Invention]

[0038] According to embodiments of the present invention, the rolling rolls for electrode manufacturing are cleaned even when they are not in operation, and the cleaning of the rolling rolls is automatically started and stopped, thereby increasing the cleaning efficiency of the rolling rolls. This also improves the manufacturing efficiency of the electrode process. Furthermore, since electrodes are manufactured using rolling rolls cleaned by the improved cleaning method, the performance of batteries can be improved. [Brief explanation of the drawing]

[0039] [Figure 1] This figure shows a rolling roll cleaning apparatus for performing a rolling roll cleaning method according to an embodiment of the present invention. [Figure 2] A flowchart of a rolling roll cleaning method according to an embodiment of the present invention is shown. [Figure 3] A flowchart of a rolling roll cleaning method according to an embodiment of the present invention is shown. [Figure 4] A flowchart of a rolling roll cleaning method according to an embodiment of the present invention is shown. [Figure 5] A flowchart of a rolling roll cleaning method according to an embodiment of the present invention is shown. [Modes for carrying out the invention]

[0040] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings, so that those skilled in the art in which the present invention belongs can easily implement it. The present invention can be implemented in several different forms and is not limited to the embodiments described herein.

[0041] To clearly explain the present invention, irrelevant parts have been omitted, and the same or similar reference numerals are used throughout the specification for identical or similar components.

[0042] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrarily indicated for the sake of explanation, and therefore the present invention is not necessarily limited to those shown. In the drawings, the thicknesses are shown enlarged to clearly represent multiple layers and regions. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for the sake of explanation.

[0043] Furthermore, when a layer, membrane, region, plate, or other part is "on top of" or "on above" another part, this includes not only when it is "directly above" the other part, but also when there is another part in between. Conversely, when we say that one part is "directly above" another part, it means that there is no other part in the middle. Also, being "on top of" or "on above" a reference part means being located above or below the reference part, and does not necessarily mean being "on top of" or "on above" in the opposite direction of gravity.

[0044] Furthermore, throughout the specification, when a part "includes" a certain component, unless otherwise stated, it means that it may include other components rather than excluding them.

[0045] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the subject is viewed from the side of a cross-section cut perpendicularly into it.

[0046] Hereinafter, an apparatus and method for automatically cleaning rolling rolls used in an electrode rolling process according to one embodiment of the present invention will be described with reference to Figures 1 and 2 to 5, respectively.

[0047] First, the apparatus and method for automatically cleaning rolling rolls used in an electrode rolling process according to one embodiment of the present invention broadly perform cleaning in a first cleaning mode and cleaning in a second cleaning mode.

[0048] The first cleaning mode is a mode in which cleaning is performed on the rolling roll 100 while the process of rolling the electrodes with the rolling roll 100 is stopped. The second cleaning mode is a mode in which cleaning is performed on the rolling roll 100 simultaneously with the process of rolling the electrodes with the rolling roll 100. To clarify, the first cleaning mode is a mode in which the rolling roll 100 is cleaned when the electrode rolling process is stopped and the equipment is not operating.

[0049] The first cleaning mode includes cases where the electrode rolling process is stopped irregularly, as well as cases where the electrode rolling process is stopped regularly. For example, an irregular stop includes cases where the equipment is stopped due to defects in the electrode rolling equipment or preceding / following processes, or when the operation of the rolling rolls 100 is stopped for reasons such as equipment inspection or replacement. Alternatively, a regularly scheduled stop may include cases where a time for completing the electrode rolling process is set separately, and the equipment does not operate for a predetermined period after the completion of the electrode rolling process.

[0050] The second cleaning mode is a mode in which, during the electrode rolling process, that is, while the equipment is in operation, the rolling rolls 100 rotate and perform electrode rolling, and at the same time, foreign matter 110 that is generated on the surface of the rolling rolls 100 is cleaned in real time.

[0051] Figure 1 shows a rolling roll 100 used in the electrode rolling process and a device 200 for automatically cleaning the rolling roll (hereinafter referred to as the "rolling roll cleaning device" for convenience).

[0052] The rolling mill cleaning apparatus 200 is broadly divided into a sensor unit 210 for measuring the brightness value of the surface of the rolling mill 100, a cleaning unit 220 for cleaning the surface of the rolling mill 100, a cleaning liquid supply unit 230 for supplying cleaning liquid to the cleaning unit 220, and a drying unit 240 for drying the surface of the rolling mill 100 that has been cleaned with the cleaning liquid. The cleaning unit 220 consists of a supply roll 221 for feeding in the cleaning cloth 224 and a winding roll 222 for unwinding the cleaned cleaning cloth 224, and is also composed of a cleaning roll (e.g., a nip roll) 223 that improves the adhesion between the rolling mill 100 and the cleaning cloth 224 in order to increase the cleaning power of the rolling mill 100.

[0053] The sensor unit 210 measures the brightness value of the surface of the rolling roll 100. The entire surface of the rolling roll 100 can be sensed, that is, the brightness value can be calculated by sensing the half of the outer surface of the cylindrical rolling roll 100 on the side where the sensor unit 210 is located. In Figure 1, the sensor unit 210 is shown as one for convenience, but the present invention is not limited to this, and two sensor units 210 can be arranged on each side of the rolling roll 100 facing each other, so that the two sensor units 210 sense half of the rolling roll 100 and calculate the brightness value.

[0054] Alternatively, the sensor unit 210 can scan while moving along the length or circumference of the cylindrical rolling roll 100, or scan while moving spirally along the outer surface of the cylindrical rolling roll 100, allowing for various modifications and changes.

[0055] Furthermore, the sensor unit 210 can selectively determine areas with particularly low brightness values ​​compared to the surrounding areas as foreign objects 110 and detect them.

[0056] The cleaning unit 220 is positioned closest to the point where the rolling roll 100 rolls the electrode, relative to the direction of rotation of the rolling roll 100, because it must be the first to remove any foreign matter adhering to the rolling roll 100 after rolling.

[0057] The cleaning cloth 224 is wound up from the supply roll 221 and transferred to the cleaning roll 223. The cleaning roll 223 is adjacent to the surface of the rolling roll 100, allowing one side of the cleaning cloth 224 to come into contact with the rolling roll 100. After passing through the cleaning roll 223, the cleaning cloth 224 is collected by the winding roll 222. The cleaning roll 223 is generally roll-shaped to facilitate the smooth transfer of the cleaning cloth 224. In this case, the cleaning roll 223 can rotate simultaneously with the movement of the cleaning cloth 224, and if the contact area between the cleaning roll 223 and the rolling roll 100 is rounded as described above, it is possible to prevent the rolling roll 100 from being damaged by the cleaning cloth 224 when it comes into contact with the rolling roll 100. On the other hand, there are no restrictions on the shape and structure of the cleaning roll 223 as long as it can guide the transfer of the cleaning cloth 224 and bring it into contact with the rolling roll 100.

[0058] The cleaning cloth 224 can smoothly absorb or remove foreign matter adhering to the rolling roll 100, and there are no restrictions on its type as long as it does not damage the surface of the rolling roll 100, but nonwoven fabric is preferred in terms of cleaning ability. Furthermore, there are no restrictions on the material of the nonwoven fabric as long as it can absorb or remove foreign matter, and cotton fibers, polyethylene fibers, polypropylene fibers, polyester, aramid fibers, cellulose fibers, rayon fibers, or nonwoven fabrics made by mixing these can be used.

[0059] The cleaning fluid supply unit 230 sprays cleaning fluid onto the cleaning cloth 224. Multiple cleaning fluid supply units 230 may be provided. For example, a cleaning fluid supply unit for supplying water and a cleaning fluid supply unit for supplying acetone may be provided. In addition, although not shown in detail in Figure 1, the cleaning fluid supply unit 230 may include a cleaning fluid storage tank, cleaning fluid transfer piping, a pump, a valve, and / or a nozzle, and the structure, shape, number, etc. of the detailed components of the cleaning fluid supply unit 230 can be modified in various ways to suit the environment in which the present invention is implemented.

[0060] There are no restrictions on the type of cleaning solution, as long as it can smoothly remove foreign matter and other contaminants. For example, cleaning solutions that can be used include water, acetone, dimethyl carbonate, dimethylformamide, N-methylformamide, sulfolane (tetrahydrothiophene-1,1-dioxide), 3-methylsulfolane, N-butylsulfone, dimethyl sulfoxide, pyoridinone (HEP), dimethylpiperidone (DMPD), N-methylpyrrolidinone (NMP), N-methylacetamide, dimethylacetamide (DMAc), dimethylformamide (DMF), diethylacetamide (DEAc), dipropyleneacetamide (DPAc), ethanol, propanol, butanol, hexanol, ethylene glycol, tetrachloroethylene, propylene glycol, toluene, torpentin, methyl acetate, ethyl acetate, phenol ether, cresol, and glycerol.

[0061] Furthermore, the rolling mill roll cleaning apparatus 200 according to the present invention can use an aqueous cleaning solution, specifically one or more selected from the group including water or alcohol-based compounds.

[0062] More specifically, the cleaning solution may be a mixture of water and an alcohol-based compound, and the alcohol-based compound may be one or more selected from the group including ethanol, propanol, butanol, pentanol, hexanol, isopropanol, heptanol, decanol, octanol, isotecanol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol methyl ether, diethylene glycol methyl ether, triethylene glycol methyl ether, ethylene glycol ethyl ether, diethylene glycol ethyl ether, triethylene glycol ethyl ether, ethylene glycol monopropyl ether, diethylene glycol monopropyl ether, triethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, and triethylene glycol monohexyl ether. More preferably, the alcohol-based compound may be one or more selected from the group including pentanol, hexanol, heptanol, octanol, and decanol.

[0063] The cleaning solution may contain acetone in an amount of 10-40% by weight, 20-30% by weight, or 30% by weight, based on the total weight of the cleaning solution. Similarly, the cleaning solution may contain water in an amount of 60-90% by weight, 70-80% by weight, or 70% by weight, based on the total weight of the cleaning solution.

[0064] The drying unit 240 dries the surface of the rolling roll 100 that has been cleaned with the cleaning solution. The drying unit 240 dries the surface of the rolling roll 100 by heating and / or blowing air. Foreign matter can be dried and removed from the roll surface by heating and / or blowing air, and any remaining liquid foreign matter can be removed by evaporation by heating and / or blowing air. The drying unit 240 may be a heater type that directly applies heat to the surface of the rolling roll 100, or it may be a hot air drying method that applies hot air to the surface of the rolling roll 100.

[0065] The rolling mill roll cleaning device 200 further includes a control unit (not shown) that controls the sensor unit 210, the cleaning unit 220, the cleaning liquid supply unit 230, the drying unit 240, and the like. The control unit receives data input from the sensor unit 210 and controls whether the cleaning unit 220, the cleaning liquid supply unit 230, and the drying unit 240 are operating.

[0066] On the other hand, in the first cleaning mode, as in the second cleaning mode, the rolling roll cleaning device 200 is fixed, and the first cleaning mode can be performed while rotating the rolling roll 100 as needed. Alternatively, in the first cleaning mode, the rolling roll 100 does not necessarily have to rotate for electrode manufacturing, so in some cases, various modifications and changes are possible, such as the individual components of the rolling roll cleaning device 200, including the sensor unit 210, cleaning unit 220, cleaning liquid supply unit 230, and drying unit 240, moving simultaneously or individually across the surface of the rolling roll 100.

[0067] On the other hand, in the second cleaning mode, the surface of the rolling roll 100 is cleaned while the electrode is being rolled by the rolling roll 100, so the use of water and water-based cleaning solutions is restricted so as not to affect the quality of the rolled electrode. However, in the first cleaning mode, the electrode is not being rolled by the rolling roll 100, so water, acetone, water-based cleaning solutions, or mixtures thereof can be used. In such cases, after cleaning in the first cleaning mode, the surface of the rolling roll 100 is dried with a cloth or drying device, and water is drained from the bottom of the equipment before the electrode rolling process is performed again, so that the quality of the produced electrode is not affected.

[0068] The rolling mill roll cleaning device 200 can be provided in multiple units, with separate rolling mill roll cleaning devices 200 for the first cleaning mode and rolling mill roll cleaning devices 200 for the second cleaning mode. Alternatively, one rolling mill roll cleaning device 200 can be provided, but multiple cleaning fluid supply units 230 can be provided to supply oil-based cleaning fluid or water-based cleaning fluid as needed. That is, some of the multiple cleaning fluid supply units 230 can supply oil-based cleaning fluid in the second cleaning mode, or in both the first and second cleaning modes, while the remaining some can supply water-based cleaning fluid in the first cleaning mode.

[0069] The following describes a method for automatically cleaning rolling rolls used in an electrode rolling process according to one embodiment of the present invention (hereinafter referred to as the "rolling roll cleaning method").

[0070] Figures 2 to 5 show flowcharts of a rolling roll cleaning method according to an embodiment of the present invention.

[0071] A method for cleaning a rolling mill includes the steps of: determining whether the rolling mill is in a non-operating state (S100); cleaning the rolling mill 100 in a first cleaning mode if the rolling mill 100 is in a non-operating state (S200); and cleaning the rolling mill 100 in a second cleaning mode if the rolling mill 100 is in an operating state (S300).

[0072] The steps of cleaning in the first cleaning mode (S200) and cleaning in the second cleaning mode (S300) can be performed by the cleaning unit 220, cleaning liquid supply unit 230, drying unit 240, control unit, etc. of the rolling roll cleaning device 200. The rolling roll cleaning device 200 is composed of multiple components, and it is also possible to have separate devices 200 for cleaning in the first cleaning mode and devices 200 for cleaning in the second cleaning mode. Alternatively, the rolling roll cleaning device 200 can perform the steps of cleaning in the first cleaning mode (S200) and cleaning in the second cleaning mode (S300), respectively. For the step of cleaning in the second cleaning mode (S300), a cleaning method used in the rolling process of electrodes during normal electrode manufacturing can also be applied.

[0073] As mentioned above, the first cleaning mode is a mode in which cleaning is performed on the rolling roll 100 while the process of rolling the electrode with the rolling roll 100 is stopped. The second cleaning mode is a mode in which cleaning is performed on the rolling roll 100 simultaneously with the process of rolling the electrode with the rolling roll 100. In the first cleaning mode, since the electrode rolling process is stopped and the rolling roll 100 is separated from the electrode sheet and not rolled, the section of the electrode sheet adjacent to the rolling roll 100 is tagged as a defective section and then disposed of as a defective section. Therefore, even if the rolling roll 100 is cleaned in the first cleaning mode, there is no problem with the quality of the final produced electrode. In some cases, such as when the electrode sheet is not located on the rolling roll 100, cleaning the rolling roll 100 will not affect the quality of the rolled electrode. In such cases, cleaning can be performed by changing at least one of the following: the type of cleaning solution used in the second cleaning mode, which is usually performed during the electrode rolling process; the number of times and amount of cleaning solution supplied; the movement speed of the cleaning cloth; and the type of cleaning solution. However, the present invention does not necessarily require this, and cleaning can also be performed in the first cleaning mode while the electrode rolling process is stopped, by keeping the type of cleaning solution used in the second cleaning mode, the number of times and amount of cleaning solution supplied, the movement speed of the cleaning cloth, and the type of cleaning solution the same.

[0074] There are two main conditions for determining whether the rolling roll 100 is in a non-operational state. The conditions for determining whether the equipment including the electrode manufacturing rolling roll 100 is in a state of being stopped and on standby, i.e., in a non-operational state, are as follows: One is that a predetermined time has elapsed during which the rotational speed of the rolling roll 100 remains at 0. The other is that a predetermined time has elapsed during which the rolling roll 100 is in a predetermined standby position. The meaning of the rolling roll 100 being in a predetermined standby position means that the rolling roll 100 is in a position where it cannot press down on the electrode (electrode sheet). For example, this may be a position where the rolling roll 100 maintains a predetermined distance from the running position of the electrode sheet. For example, in the electrode rolling process, when an electrode is rolled by a pair of rolling rolls 100, there may be a position where the distance between the pair of rolling rolls 100 is greater than the thickness of the electrode. However, the present invention is not limited thereto, and can be modified and applied in various ways, such as meaning that the operation of the equipment is completely finished and the rolling rolls 100 are positioned in a pre-designated location (an automatically moved location) for cleaning, inspection, etc., and that position is maintained.

[0075] On the other hand, if both conditions of the rotational speed of the rolling roll 100 and the standby position of the rolling roll 100 are met, it can be determined that the rolling roll 100 is in a non-operating state. However, depending on the environment in which the present invention is implemented, it may also be determined that the rolling roll 100 is in a non-operating state if either of the two conditions is met.

[0076] More specifically, referring to Figure 3, the step of determining whether the rolling roll 100 is in a non-operating state (S100) includes: receiving input of the rotational speed (drive speed) of the rolling roll 100 (S110-1); if the rotational speed of the rolling roll 100 is 0, counting the waiting time of the rolling roll 100 (S120-1); and if a first predetermined time has elapsed with the rotational speed of the rolling roll 100 at 0, determining that the rolling roll 100 is in a non-operating state (S130). Here, waiting time means the time during which the rotational speed of the rolling roll 100 remains at 0. In steps S110-1 and S120-1, the rotational speed of the rolling roll 100 may be sensed by a speed sensing sensor, or it may be counted based on the time when a drive stop command is sent to the rolling roll 100 from a control unit (not shown) connected to the rolling roll 100. Thus, the present invention can be applied in various ways.

[0077] Alternatively, referring to Figure 4, the step (S100) of determining whether the rolling roll 100 is in a non-operating state includes: receiving input of the position of the rolling roll 100 (S110-2); counting the waiting time of the rolling roll 100 if the rolling roll 100 is in a predetermined waiting position (S120-2); and determining that the rolling roll 100 is in a non-operating state if a second predetermined time has elapsed while the rolling roll 100 is in the predetermined waiting position (S130). Here, waiting time means the time during which the rolling roll 100 maintains the state of being in the predetermined waiting position. In steps S110-2 and S120-2, the position of the rolling roll 100, such as whether it has moved toward the electrode or moved away from the electrode, can also be sensed by a position sensing sensor, or the waiting position of the rolling roll 100 can be indirectly sensed by sensing the pressing force of the rolling roll 100 with a pressure sensing sensor such as a load cell.

[0078] Alternatively, if both conditions are met, it can be determined that the rolling mill roll 100 is in a non-operational state.

[0079] For example, the steps shown in Figure 3 can be performed first, followed sequentially by the steps shown in Figure 4. That is, after a first predetermined time has elapsed with the rolling roll 100 rotating at 0, and then a second predetermined time has elapsed with the rolling roll 100 again in a predetermined standby position, it can be determined that the rolling roll 100 is ultimately in a non-operational state.

[0080] Conversely, the steps shown in Figure 4 can be performed first, followed sequentially by the steps shown in Figure 3. That is, after a second predetermined time has elapsed with the rolling roll 100 in a predetermined standby position, and then a first predetermined time has elapsed with the rolling roll 100's rotational speed at 0, it can be determined that the rolling roll 100 is ultimately in a non-operational state.

[0081] Alternatively, the steps shown in Figures 3 and 4 can be performed simultaneously. Steps (S110-1) and (S110-2) can be performed simultaneously, and then steps (S120-1) and (S120-2) can be performed simultaneously. If a first predetermined time has elapsed with the rolling roll 100 rotating at 0 and a second predetermined time has elapsed with the rolling roll 100 in a predetermined standby position, it can be determined that the rolling roll 100 is in a non-operational state (S130). To elaborate, the rotational speed and position of the rolling roll 100 are input. If the rotational speed of the rolling roll 100 is 0, the standby time of the rolling roll 100 is counted. Simultaneously, if the rolling roll 100 is in a standby position, the standby time of the rolling roll 100 is counted. If a first predetermined time has elapsed with the rolling roll 100 rotating at 0 and a second predetermined time has elapsed with the rolling roll 100 in a standby position, it can be determined that the rolling roll 100 is in a non-operational state.

[0082] The first predetermined time and the second predetermined time are, for example, any one of the periods between 0 minutes and 100 minutes. However, the present invention is not limited to the above, and the first predetermined time and the second predetermined time can be appropriately selected according to the various environments to which the present invention is applied.

[0083] Referring to Figure 5, when the rolling roll 100 is in a non-operating state, the step of cleaning the rolling roll 100 in the first cleaning mode (S200) includes: measuring the brightness value of the surface of the rolling roll 100 with the sensor unit 210 (S210); and, if the brightness value of the surface of the rolling roll 100 is less than or equal to a first predetermined brightness value, cleaning the rolling roll 100 with the cleaning unit 220 for a third predetermined time (S220); and measuring the brightness value of the surface of the cleaned rolling roll 100 to determine whether the brightness value is greater than or equal to a second predetermined brightness value (S230).

[0084] At this time, the second predetermined brightness value is greater than the first predetermined brightness value. The higher the brightness value, the cleaner the rolling roll. The first predetermined brightness value and the second predetermined brightness value are each one of the brightness values ​​between 0 and 100%, and can be appropriately selected according to the various environments to which the present invention is applied. For example, the first predetermined brightness value may be 40% and the second predetermined brightness value may be 80%. The third predetermined time is, for example, one of 3 to 10 minutes, for example, 5 minutes, but the present invention is not limited to the above, and the third predetermined time can be appropriately selected according to the various environments to which the present invention is applied.

[0085] In relation to step (S210), in the second cleaning mode, there may be restrictions on the type and amount of cleaning solution used because cleaning may degrade the quality of the electrodes. In some cases, foreign matter, residues, or contaminants 110 that were not removed in the second cleaning mode may remain on the surface of the rolling roll 100. As a result, the brightness value of the surface of the rolling roll 100 may be slightly lower. Depending on the environment in which the present invention is implemented (i.e., depending on the type of active material of the electrodes rolled by the rolling roll 100, the degree of cleaning in the second cleaning mode, etc.), the operator can pre-set a first predetermined brightness value of the surface of the rolling roll 100 in which the first cleaning mode should be started.

[0086] On the other hand, in step (S210), if the brightness value of the surface of the rolling roll 100 exceeds a first predetermined brightness value, the first cleaning mode is not performed and terminates immediately.

[0087] In step (S220), the rolling roll 100 is cleaned for a third predetermined time. Then, in step (S230), the brightness value of the rolling roll 100 is measured, and it is determined whether the brightness value is equal to or greater than a second predetermined brightness value.

[0088] If the surface of the rolling roll 100 becomes clean and its brightness value increases, that is, if the brightness value of the surface of the rolling roll 100 is equal to or greater than the second predetermined brightness value, the step of cleaning in the first cleaning mode is automatically terminated. However, if foreign matter, residue, or contaminants 110 still remain on the surface of the rolling roll 100 and the brightness value of the surface of the rolling roll 100 is still less than the second predetermined brightness value, the step of cleaning the rolling roll 100 for a third predetermined time (S220) is performed again. That is, step (S220) is repeated until the termination of the first cleaning mode is declared in step (S230), that is, until the step of cleaning in the first cleaning mode is automatically terminated.

[0089] This allows the rolling roll 100 to be automatically cleaned when it is not in operation, unlike the conventional method where an operator manually cleans the rolling roll 100 each time. To elaborate, the same process is repeated by measuring the brightness value, cleaning the rolling roll 100 for a third predetermined time, measuring the brightness value again, and if it does not reach the desired brightness value (i.e., the second predetermined brightness value), cleaning the rolling roll 100 again for the third predetermined time. This process enables the automation of cleaning the rolling roll 100 when it is not in operation.

[0090] Furthermore, according to the embodiment of the present invention, the rolling rolls for electrode manufacturing are cleaned even when they are not in operation, and the cleaning of the rolling rolls is automatically started and stopped, thus increasing the cleaning efficiency of the rolling rolls. This also improves the manufacturing efficiency of the electrode process. In addition, since electrodes are rolled using rolling rolls cleaned by the improved cleaning method, the performance of the battery can be improved.

[0091] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art that utilize the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0092] 100 rolling rolls 110 Foreign object 200 Rolling Roll Cleaning Machine 210 Sensor section 220 Cleaning section 230 Cleaning fluid supply unit 240 Drying section

Claims

1. A method for automatically cleaning rolling rolls used in an electrode rolling process, A step of determining whether the rolling rolls are in a non-operational state, and If the rolling roll is not in operation, the step includes cleaning the rolling roll in a first cleaning mode. In the first cleaning mode, the rolling process of rolling the electrodes with the rolling rolls is stopped, and the rolling rolls are cleaned. The step of determining whether the rolling roll is in a non-operational state is: A step of receiving input for the position of the rolling roll, If the rolling roll is in a predetermined waiting position, the steps include counting the waiting time of the rolling roll, and A cleaning method comprising the step of determining that the rolling roll is in a non-operational state if a second predetermined time has elapsed while the rolling roll is in a predetermined standby position.

2. A method for automatically cleaning rolling rolls used in an electrode rolling process, A step of determining whether the rolling rolls are in a non-operational state, and If the rolling roll is not in operation, the step includes cleaning the rolling roll in a first cleaning mode. In the first cleaning mode, the rolling process of rolling the electrodes with the rolling rolls is stopped, and the rolling rolls are cleaned. The step of determining whether the rolling roll is in a non-operational state is: A step of receiving input for the rotational speed and position of the rolling roll, respectively. If the rotational speed of the rolling roll is 0, the waiting time of the rolling roll is counted. If the rolling roll is in a predetermined waiting position, the steps include counting the waiting time of the rolling roll, and A cleaning method comprising the step of determining that the rolling roll is in a non-operating state if a first predetermined time has elapsed while the rotational speed of the rolling roll is 0 and a second predetermined time has elapsed while the rolling roll is in a predetermined standby position.

3. If the rolling rolls are in operation, the further step includes cleaning the rolling rolls in a second cleaning mode. The cleaning method according to claim 1 or 2, wherein in the second cleaning mode, the step of rolling the electrode with the rolling roll is performed and at the same time the rolling roll is cleaned.

4. The cleaning method according to claim 3, wherein in each of the first cleaning mode and the second cleaning mode, at least one of the following is different: the type of cleaning solution, the number of times and amount of cleaning solution supplied, and the speed at which the cleaning cloth moves.

5. The step of cleaning the rolling rolls in the first cleaning mode is: The steps of measuring the brightness value of the surface of the rolling roll, and The cleaning method according to claim 1 or 2, further comprising the step of cleaning the rolling roll for a third predetermined time if the brightness value of the surface of the rolling roll is less than or equal to a first predetermined brightness value.

6. The step of cleaning the rolling rolls in the first cleaning mode is: The method further includes measuring the brightness value of the surface of the cleaned rolling roll and determining whether the brightness value is equal to or greater than a second predetermined brightness value. The cleaning method according to claim 5, wherein if the brightness value of the surface of the rolling roll is equal to or greater than a second predetermined brightness value, the step of cleaning in the first cleaning mode is automatically terminated.

7. The step of cleaning the rolling rolls in the first cleaning mode is: The method further includes measuring the brightness value of the surface of the cleaned rolling roll and determining whether the brightness value is equal to or greater than a second predetermined brightness value. The cleaning method according to claim 5, wherein if the brightness value of the surface of the rolling roll is less than a second predetermined brightness value, the step of cleaning the rolling roll for a third predetermined time is repeated.

8. The cleaning method according to claim 5, wherein the third predetermined time is a time selected from 3 minutes to 10 minutes.

9. The cleaning method according to claim 6, wherein the second predetermined brightness value is greater than the first predetermined brightness value.

10. The cleaning method according to claim 6, wherein the first predetermined brightness value is 40% and the second predetermined brightness value is 80%.

11. The cleaning method according to claim 3, wherein the number of times and the amount of cleaning solution supplied in the first cleaning mode are greater than the number of times and the amount of cleaning solution supplied in the second cleaning mode.

12. The cleaning method according to claim 1 or 2, wherein the cleaning solution provided in the first cleaning mode is an oil-based cleaning agent.

13. The cleaning method according to claim 1 or 2, wherein the cleaning solution provided in the first cleaning mode is selected from water, acetone, an aqueous cleaning solution, or a combination of at least two of these.

14. The cleaning method according to claim 3, wherein the cleaning solution provided in the second cleaning mode is an oil-based cleaning agent.

15. An apparatus for automatically cleaning rolling rolls for performing the cleaning method described in claim 1 or 2, A sensor unit for measuring the brightness value of the surface of the rolling roll, A cleaning liquid supply unit that supplies cleaning liquid to the rolling rolls, A cleaning unit for cleaning the surface of the rolling roll, and A cleaning apparatus including a control unit that receives data input from the sensor unit and controls whether or not the cleaning fluid supply unit and the cleaning unit can be operated.

16. The cleaning fluid supply unit comprises multiple cleaning fluid supply units, Some of the aforementioned multiple cleaning fluid supply units supply an oil-based cleaning agent. The cleaning apparatus according to claim 15, wherein the remaining of the plurality of cleaning fluid supply units supplies water, acetone, an aqueous cleaning solution, or a combination of at least two of these.

17. The cleaning apparatus consists of multiple cleaning apparatuses, The cleaning apparatus according to claim 15, wherein some of the plurality of cleaning devices are devices for a first cleaning mode, and the remaining of the plurality of cleaning devices are devices for a second cleaning mode.

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