Infrared heat source module and method of manufacturing electrodes using the module

Abstract

The present application relates to an infrared heat source module and a method of manufacturing an electrode using the infrared heat source module, which can minimize problems such as wrinkles or cracks in the electrode, and can improve drying efficiency of a coated portion present in a current collector, even if a pattern of the coated portion and an uncoated portion present in the current collector varies.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2021-0080776, filed on June 22, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to an infrared heat source module and a method for manufacturing electrodes using the infrared heat source module. Background Technology

[0004] Secondary batteries typically consist of electrodes (positive and negative electrodes), a separator, and an electrolyte, and are manufactured through a series of steps comprising electrode fabrication, assembly, and activation. Here, the positive and negative electrodes are prepared by coating a slurry containing active materials onto a current collector such as an aluminum or copper sheet, mesh, membrane, or foil, and then drying it.

[0005] Meanwhile, the electrode process, also known as the electrode plate process, is the process of manufacturing the positive and negative electrodes, which are the basic components of a secondary battery. The electrode process can be specifically divided into mixing, coating, rolling (calendering), cutting, and drying processes.

[0006] In the coating process, the positive electrode slurry prepared in the mixing process is applied to the positive electrode current collector. Here, the negative electrode slurry is also applied to the negative electrode current collector during the coating process. The slurry applied to each current collector is subjected to a rolling process to increase its energy density, and then cut in a cutting process to meet the design specifications.

[0007] After cutting and before proceeding to the assembly process, a drying process removes moisture from the slurry coated onto each current collector. At this stage, hot air or infrared radiation is primarily used to dry the coating slurry, with infrared drying methods employed to ensure better drying efficiency. Patent Document 1 relates to a method for manufacturing electrodes, which includes the step of drying electrode sheets, characterized by irradiating the electrode sheets with infrared radiation in the wavelength range of 1 to 3 μm.

[0008] However, when the infrared drying method is applied to the drying process of the electrode, depending on the process environment, the coated part (the part coated with slurry) and the uncoated part (the part not coated with slurry) in the current collector have different coefficients of thermal expansion, which may cause problems such as wrinkles or cracks in the electrode.

[0009] Problems such as wrinkles or cracks in the electrodes can affect the adhesion between the slurry and the current collector, and in such cases, problems such as slurry and current collector separation may occur during post-processing.

[0010] Therefore, when applying infrared drying methods to the drying process of electrodes, a method is needed that can minimize problems such as wrinkles or cracks in the electrodes.

[0011] [Existing Technical Documents]

[0012] (Patent Document 1) Korean Unexamined Patent Publication No. 10-2016-0037763 Summary of the Invention

[0013] Technical issues

[0014] This application relates to an infrared heat source module that can minimize problems such as wrinkles or cracks in electrodes, and a method for manufacturing electrodes using the infrared heat source module.

[0015] Furthermore, this application relates to an infrared heat source module that can minimize problems such as wrinkles or cracks in electrodes even when the patterns of coated and uncoated portions in the current collector are different, and a method for manufacturing electrodes using the infrared heat source module.

[0016] In addition, this application relates to an infrared heat source module that can improve the drying efficiency of the coated portion present in the current collector, and a method for manufacturing electrodes using the infrared heat source module.

[0017] Technical solution

[0018] An example of an infrared heat source module according to this application is used for drying electrode slurry. The infrared heat source module may include: a frame extending in one direction; one or more shielding films mounted on the frame; and an infrared heat source mounted on the frame, wherein the shielding films are mounted on the frame such that the shielding films can be repositioned along one direction of the frame and can block at least a portion of the heat generated from the infrared heat source.

[0019] Additionally, a method for manufacturing an electrode according to an example of this application may include a step of drying an electrode paste formed on a current collector, wherein the current collector contains a coated portion coated with electrode paste and an uncoated portion uncoated with electrode paste. With an infrared heat source module according to an example of this application placed on the current collector coated with electrode paste, drying is performed by applying heat from the infrared heat source module. During the drying process, a shielding film of the infrared heat source module is positioned to block at least a portion of the heat applied from the infrared heat source module to the uncoated portion.

[0020] Beneficial effects

[0021] This application provides an infrared heat source module that can minimize problems such as wrinkles or cracks in electrodes, and a method for manufacturing electrodes using the infrared heat source module.

[0022] Furthermore, this application can provide an infrared heat source module that can minimize problems such as wrinkles or cracks in the electrode even when the patterns of the coated and uncoated portions in the current collector are different, as well as a method for manufacturing electrodes using the infrared heat source module.

[0023] In addition, this application can provide an infrared heat source module that can improve the drying efficiency of the coated portion present in the current collector, and a method for manufacturing electrodes using the infrared heat source module. Attached Figure Description

[0024] Figure 1 This is a brief example diagram illustrating an infrared heat source module according to an example of this application.

[0025] Figure 2 This is an exemplary diagram used to explain the change in position of the shielding film in an infrared heat source module according to an example of this application.

[0026] Figure 3 This is an exemplary diagram used to explain a position-changing component with grooves and tracks in an infrared heat source module according to an example of this application, and a shielding film coupled to the position-changing component.

[0027] Figure 4 This is an example diagram used to explain the situation in an infrared heat source module according to an example of this application, where the shielding film is located inside the opening, at the top end of the opening, and at the bottom end of the opening.

[0028] Figure 5 This is an example diagram used to explain a method of manufacturing an electrode according to an example of this application.

[0029] Figure 6 This is an example diagram used to explain a drying method applied to conventional methods of manufacturing electrodes.

[0030] Figure 7 This is a view showing the state of the shielding membrane before it is coupled to the groove of the position-changing component.

[0031] Figure 8 and Figure 9 This is a view of the drying rate of the coated portion present in the current collectors measured in Example 1 and Comparative Example 1.

[0032] Figure 10 This is a view of an electrode with wrinkles formed by a drying process according to Comparative Example 1. Detailed Implementation

[0033] In this application, when the physical properties are affected by the measurement temperature, the relevant physical properties are those measured at room temperature, unless otherwise stated.

[0034] The term “room temperature” as used in this application is the natural temperature without heating or cooling, which may refer to any temperature in the range of 10°C to 30°C, such as about 15°C or higher, about 18°C ​​or higher, about 20°C or higher, about 23°C or higher, about 27°C or lower, or 25°C.

[0035] The term “mid-infrared (MIR)” as used in this application may refer to light with a wavelength range of 1 μm to 50 μm.

[0036] As used in this application, the term "current collector" can refer to a metal foil suitable for use in a secondary battery, wherein aluminum foil can be used when manufacturing the positive electrode and copper foil can be used when manufacturing the negative electrode. Typically, when manufacturing a secondary battery, the current collector is made of a long sheet of metal foil, and there is no particular limitation on its thickness, but it can have a thickness of, for example, from 3 μm to 500 μm.

[0037] As used in this application, the term "electrode paste" or "paste" includes both positive and negative electrode pastes to be coated onto the current collector. Positive electrode paste typically comprises a positive electrode active material, a conductive material, and a binder, while negative electrode paste typically comprises a negative electrode active material and a binder. Here, as the positive electrode active material, materials known in the art can be used, and their type is not particularly limited; for example, it can be lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, etc. Similarly, as the negative electrode active material, materials known in the art can also be used, and their type is not particularly limited; for example, it can be graphite and hard carbon, etc. In the case of the binder, polyvinylidene fluoride (PVDF) is exemplified, but if it is known in the art, it can be used without limitation.

[0038] Reference Figure 1 According to an example of this application, the infrared heat source module 10 includes a frame 110 extending in one direction, one or more shielding films 120 mounted on the frame, and an infrared heat source 130 mounted on the frame. Meanwhile, infrared rays emitted from the infrared heat source 130 can be emitted in the form of heat.

[0039] According to one example of this application, the infrared heat source module 10 can be used to dry electrode paste coated on the current collector.

[0040] According to an example of this application, the frame 110 of the infrared heat source module 10 may be provided with an opening 111. The infrared heat source 130 can emit infrared rays, and the emitted infrared rays can be exposed to the outside through the opening 111 in the frame 110. The infrared rays (or heat) exposed to the outside through the opening 111 come into contact with the electrode paste coated on the current collector, and the electrode paste is dried while removing moisture. The term "external" may refer to the exterior of the infrared heat source module 10.

[0041] exist Figure 1 The diagram shows only one opening 111, however, one or more openings 111 can be formed without particular limitation.

[0042] Additionally, the frame 110 may include a support member 112, which is a member excluding the opening 111. Here, the support member 112 provides space in which components such as the shielding film 120 and the infrared heat source 130 are mounted to the frame 110. (See reference...) Figure 1 The shielding film 120 and the infrared heat source 130 are installed in the support component 112.

[0043] The support member 112 can surround the opening 111, allowing the shielding membrane 120 to be stably mounted on the frame 110. (Reference) Figure 1 A rectangular opening 111 is formed at the center of the frame 110, and a support member 112 surrounds the opening 111.

[0044] Additionally, refer to Figure 1 The support member 112 has a rectangular shape, and the opening 111 has a rectangular shape, so that the frame 110 has a rectangular shape and opens a rectangular space in the center. However, the shapes of the opening 111 and the support member 112 are... Figure 1 The shapes shown are rectangles, but this is just an example; there are no particular restrictions on their shapes.

[0045] According to one example of this application, the shielding film 120 of the infrared heat source module 10 can be mounted on the frame 110 to block at least a portion of the infrared radiation (or heat) generated from the infrared heat source 130. Specifically, the shielding film 120 can be mounted on the support member 112 of the frame 110 and can also be mounted on the position changing member 150 as described below, which is mounted on the support member 112 of the frame 110.

[0046] According to an example of this application, the shielding film 120 of the infrared heat source module 10 can change position in one direction along the frame 110.

[0047] Here, changing the position of the shielding film 120 means that the shielding film 120 can move in any direction. For example, refer to... Figure 1 The frame 110 extends in the x-axis direction, and the shielding film 120 can be repositioned along the x-axis direction, which is one direction in which the frame 110 extends. That is, the shielding film 120 can be repositioned not only in the +x direction, but also in the -x direction (180° of the +x direction).

[0048] Furthermore, in another example, depending on design conditions, the shielding membrane 120 can be repositioned in a direction other than the direction in which the frame 110 extends. For example, in Figure 1 In this system, the position can be changed along the y-axis, and in some cases, it can be changed along a direction tilted at 45 degrees from the x-axis.

[0049] In the electrode manufacturing process of secondary batteries, electrode slurry is coated onto a current collector, followed by a drying process. Within the current collector, there are coated portions and uncoated portions. Typically, during the drying process, the coated and uncoated portions are dried in batches without differentiation. However, due to the difference in the coefficients of thermal expansion between the coated and uncoated portions, problems such as electrode wrinkles or cracks occur.

[0050] Furthermore, according to existing technology, drying is performed in batches without distinguishing between coated and uncoated portions. In this case, the uncoated portions of the uncoated electrode paste are dried first, while the coated portions require more drying time to allow the electrode paste in the coated portions to dry to the interior. As a result, when the electrode paste in the coated portions undergoes a drying process sufficient to dry to the interior, the uncoated portions become over-dried, and problems such as wrinkles or cracks in the electrodes caused by the difference in the coefficients of thermal expansion between the coated and uncoated portions are further accelerated by this over-drying.

[0051] In addition, due to wrinkles or cracks formed on the electrodes, uneven infrared radiation (or heat) comes into contact with the electrode paste in the coated area, thus limiting uniform drying. Furthermore, the infrared radiation (or heat) is dispersed to the outside through the wrinkles or cracks, thereby reducing the drying efficiency of the electrode paste in the coated area.

[0052] Conversely, if the drying time is shortened to prevent over-drying of the uncoated areas, there is a problem that the electrode paste in the coated areas may not be sufficiently dried.

[0053] An example of the infrared heat source module 10 according to this application includes a shielding film 120, wherein the shielding film 120 minimizes infrared radiation (or heat) emitted from the infrared heat source 130 to prevent contact with uncoated portions, and allows infrared radiation (or heat) emitted from the infrared heat source 130 to contact coated portions, thereby minimizing problems caused by the difference in thermal expansion coefficients between coated and uncoated portions. Furthermore, the infrared heat source module 10 can reduce wrinkles or cracks in the electrodes, thereby improving the drying efficiency of the electrode paste on the coated portions.

[0054] Furthermore, according to an example of this application, the infrared heat source module 10 can prevent excessive drying that may occur in the uncoated portion through the shielding film 120, thereby ensuring that the electrode paste in the coated portion is sufficiently dried. This can both suppress the acceleration of electrode wrinkling or cracking and improve the drying efficiency of the electrode paste in the coated portion.

[0055] Additionally, the shielding film 120 of the infrared heat source module 10 according to an example of this application can be repositioned so that even if there are pattern variations in the coated and uncoated portions present in the current collector, infrared radiation (or heat) can be minimized to avoid contact with the uncoated portions, while allowing infrared radiation (or heat) to contact the coated portions.

[0056] According to one example of this application, multiple shielding films 120 may exist for the infrared heat source module 10, and when multiple shielding films 120 exist, each shielding film 120 can be repositioned independently. However, a change of position means moving in any direction as described above, but does not mean changing the arrangement position of each shielding film 120.

[0057] Reference Figure 2 The shielding film 120 includes a first shielding film 120a, a second shielding film 120b, and a third shielding film 120c, which are arranged sequentially from the left end of the frame 110 to the right. Here, the ability of the multiple shielding films 120 to be independently repositioned means that the first shielding film 120a, the second shielding film 120b, and the third shielding film 120c can each move independently in the +x or -x direction. However, this does not mean that the second shielding film 120b moves beyond the first shielding film 120a in the rightward direction from the left end of the frame 110, such that the arrangement position of the second shielding film 120b, the first shielding film 120a, and the third shielding film 120c differs from the previous arrangement position.

[0058] According to an example of this application, the infrared heat source module 10 may further include a position-changing component 150 mounted on a frame 110. Specifically, the position-changing component 150 may be mounted on a support member 112 of the frame 110, or mounted on the wall surface of the support member 112 inside the opening 111 of the frame 110. The shielding membrane 120 may be coupled to the position-changing component 150 mounted on the frame 110 for repositioning.

[0059] In the position-changing component 150, a groove 151 with a predetermined space can be formed for coupling the shielding film 120. A portion of the shielding film 120 can be coupled while being inserted into the groove 151, and even when coupled, the groove 151 can have more free space. The free space of the groove 151 refers to the space in which the shielding film 120 can be repositioned to a certain extent without separating from the groove 151. For example, as... Figure 7 As shown, the two ends of the shielding film 120 can be movably coupled while being inserted into the groove 151.

[0060] Additionally, the position-changing component 150 may include a track 152 for smoothly changing the position of the shielding membrane 120. A portion of the shielding membrane 120 may be coupled to the track 152, and the position of the shielding membrane 120 may be smoothly changed by a moving device (e.g., a wheel) disposed on the track 152. In another example, the track 152 may be disposed within the aforementioned groove 151, and the shielding membrane 120 may be inserted into the groove 151 while being coupled to the track 152, thereby achieving more stable repositioning.

[0061] Reference Figure 3 The track 152 disposed within the groove 151 can be confirmed. The shielding film 120 is coupled to the track 152 disposed within the groove 151, and the position of the shielding film 120 can be easily changed due to the wheels disposed within the track 152.

[0062] The position changing component 150 can be located inside or outside the support component 112 of the frame 110. The position of the shielding membrane 120 can be changed according to the position of the position changing component 150.

[0063] The shielding film 120 can be located at the lower end of the infrared heat source 130. Here, the lower end of the infrared heat source 130 can refer to the area between the infrared heat source 130 and the current collector coated with electrode paste. The shielding film 120 can block at least a portion of the infrared radiation (or heat) generated from the infrared heat source 130 by being located at the lower end of the infrared heat source 130.

[0064] Furthermore, the shielding membrane 120 can be positioned within the opening 111. In this case, the position-changing component 150 can be disposed inside the support component 112 of the frame 110. Positioning within the opening 111 means that some or all of the shielding membrane 120 is positioned within the opening 111.

[0065] Meanwhile, the opening 111 can have a depth equal to the thickness of the supporting member 112, and can be divided into an upper end and a lower end. Here, the upper end of the opening 111 refers to the vicinity of the surface of the opening 111, which is not inside the opening 111 but close to the infrared heat source 130, and the lower end of the opening 111 refers to the vicinity of the surface of the opening 111, which is not inside the opening 111 but far away from the infrared heat source 130. The shielding film 120 can be located at the upper end or the lower end of the opening 111. At this time, the position changing member 150 can be provided on the supporting member 112 of the frame 110.

[0066] refer to Figure 4 Examples of shielding membrane 121 located at the upper end of opening 111, shielding membrane 122 located inside opening 111, and shielding membrane 123 located at the lower end of opening 111 can be identified. Figure 4 Only one example of the location of the shielding membrane 120 is shown. The shielding membrane 120 may be disposed at one or more of the upper, inner and lower ends of the opening 111.

[0067] When multiple shielding films 120 are present, each shielding film 120 can be independently positioned in one or more of the group consisting of the interior of the opening 111, the upper end of the opening 111, and the lower end of the opening 111.

[0068] In order to block at least a portion of the infrared radiation (or heat) generated by the infrared heat source 130, a coating body that forms an infrared reflective coating or an infrared absorbing (blocking) coating on a substrate, a coating body that contains a compound that absorbs infrared radiation in the substrate, or other substrates that reflect or absorb infrared radiation can be used as the shielding film 120, and such stainless steel plates can be used, but are not particularly limited thereto.

[0069] In addition, if the shielding film 120 can block infrared rays (or heat) from passing through the opening 111, its shape and arrangement are not particularly restricted.

[0070] An infrared heat source module 10 according to an example of this application includes an infrared heat source 130. Infrared rays (or heat) generated from the infrared heat source 130 pass through an opening 111 in the frame 110, and the infrared rays (or heat) passing through the opening 111 can dry the electrode paste coated on the current collector. However, when a shielding film 120 is present in the path of the infrared rays (or heat) generated from the infrared heat source 130, the infrared rays (or heat) are blocked at the location corresponding to the shielding film 120 and cannot reach the current collector.

[0071] Infrared heat source 130 can emit light with wavelengths of 3 μm or greater, 4 μm or greater, 5 μm or greater, 6 μm or greater, 7 μm or greater, 8 μm or greater, 9 μm or greater, 10 μm or greater, 15 μm or greater, or 20 μm or greater. In another example, infrared heat source 130 can emit light with wavelengths of 50 μm or less, 48 ​​μm or less, 46 μm or less, 44 μm or less, 42 μm or less, 40 μm or less, 35 μm or less, or 30 μm or less. The wavelength of the light emitted by infrared heat source 130 can be within a range formed by appropriately selecting the upper and lower limits as described above.

[0072] As described above, the emitted light can be exposed to the outside through the opening 111, and the exposed light can reach the electrode paste coated on the current collector, thereby drying the electrode paste.

[0073] If the infrared heat source 130 can emit light at a fixed position, then there are no particular limitations on the fixing device. (Reference) Figure 1 The infrared heat source 130 can be fixed by a fixing component 160 present in the frame 110. That is, the infrared heat source 130 can be fixed to the frame 110 by the fixing component 160, and when the infrared heat source 130 is fixed, the current collector can be irradiated with a predetermined amount of light.

[0074] Furthermore, if the infrared heat source 130 can emit light into the opening 111, its shape is not particularly limited. (See reference) Figure 1 The infrared heat source 130 can have a shape that extends in one direction.

[0075] In addition, one or more infrared heat sources 130 can be set, and there is no particular limitation on their number. (Reference) Figure 1 The infrared heat source module 10 can also be configured with two infrared heat sources 130.

[0076] According to an example of this application, the infrared heat source module 10 may also include a control device for identifying uncoated portions on the current collector and controlling the shielding film 120 so that the shielding film 120 is automatically repositioned in the appropriate position.

[0077] The control device can identify the coated and uncoated portions in the current collector, compile the position of the uncoated portion into data, and then control the shielding film 120 to reposition itself to the position corresponding to the uncoated portion. At this time, the control device can change the position of the shielding film 120 by controlling the position changing component 150.

[0078] Additionally, the control device can reposition the shielding film 120 closest to the planar distance to the position corresponding to the uncoated portion. Here, planar distance can refer to the distance between various objects in a plane when viewed from the position of the infrared heat source 130 toward the frame 110.

[0079] An example of the method for manufacturing an electrode according to this application includes the step of drying an electrode slurry formed on a current collector.

[0080] In a current collector, there is a coated portion coated with electrode paste and an uncoated portion without electrode paste. The uncoated portion can also be called the unpatterned portion.

[0081] Furthermore, in a method for manufacturing an electrode according to an example of this application, drying can be performed using an infrared heat source module according to an example of this application. Drying can be carried out by applying infrared radiation (or heat) using the module while the infrared heat source module is placed on a current collector coated with a slurry. Here, the infrared heat source module can be positioned at a location with an appropriate height difference without contacting the coated current collector or the electrode slurry coated on the current collector, allowing infrared radiation (or heat) to be applied to the coated portion of the current collector.

[0082] Furthermore, in a method of manufacturing an electrode according to an example of this application, the shielding film of the infrared heat source module can be positioned during the drying process such that at least a portion of the infrared radiation (or heat) applied from the infrared heat source of the infrared heat source module to the uncoated portion is blocked. Here, the position where the shielding film of the infrared heat source module is positioned to block at least a portion of the infrared radiation (or heat) applied to the uncoated portion can be defined as the position corresponding to the uncoated portion.

[0083] Reference Figure 5 It can be confirmed that there is a coated portion C with electrode paste and an uncoated portion N without electrode paste. According to an example of this application, the infrared heat source module 10 is positioned on a current collector that moves in one direction, thereby drying the coated portion C coated on the current collector. Here, the shielding film 120 of the infrared heat source module 10 is present at a position corresponding to the uncoated portion N on the current collector, thereby blocking at least a portion of the infrared radiation (or heat) emitted from the infrared heat source 130.

[0084] Traditionally, such as Figure 6 As shown, drying is carried out in batches without distinguishing between the coated portion C and the uncoated portion N on the current collector. However, due to the difference in the coefficient of thermal expansion between the coated portion C and the uncoated portion N, problems such as wrinkles or cracks in the electrodes exist.

[0085] In this regard, by utilizing the shielding film 120 of the infrared heat source module 10 to block a portion of the infrared rays (or heat) from reaching the uncoated portion on the current collector, the method of manufacturing the electrode according to an example of this application can reduce the difference in thermal expansion between the coated and uncoated portions and prevent problems such as wrinkles or cracks in the electrode.

[0086] Furthermore, in an example of the electrode manufacturing method according to this application, drying can be performed while the current collector on which the electrode paste is formed moves in one direction. That is, in the electrode manufacturing method, the coated portion can be dried by the infrared heat source module 10 while the current collector continues to move in one direction, and the shielding film 120 of the infrared heat source module 10 blocks at least a portion of the infrared rays (or heat) from reaching the uncoated portion, which can prevent problems such as wrinkles or cracks in the electrode, while allowing continuous drying.

[0087] In a method of manufacturing an electrode according to an example of this application, the infrared heat source module 10 may move in the same direction as the current collector or in the opposite direction to the current collector, and during the movement of the infrared heat source module 10, the shielding film 120 may be positioned to block at least a portion of the infrared rays (or heat) from reaching the uncoated portion.

[0088] The method of manufacturing the electrodes can also involve drying the coated portion on the current collector while the infrared heat source module 10 is fixed, or it can involve drying the coated portion on the current collector while the infrared heat source module 10 is moving in the same or opposite direction as the current collector. Even in this case, the shielding film 120 of the infrared heat source module 10 is continuously positioned at the position corresponding to the uncoated portion, thereby blocking at least a portion of the infrared rays (or heat) from reaching the uncoated portion.

[0089] Furthermore, in the method of manufacturing the electrode, even when the position of the uncoated portion on the current collector is changed while the infrared heat source module 10 is moving, the shielding film 120 of the infrared heat source module 10 is continuously positioned at the position corresponding to the uncoated portion whose position has changed, thereby blocking at least a portion of infrared rays (or heat) from reaching the uncoated portion.

[0090] In one example of the method of manufacturing an electrode according to this application, there may be two or more uncoated portions in the current collector, and the shielding film 120 of the infrared heat source module 10 may be positioned and disposed between all the uncoated portions and the infrared heat source 130.

[0091] In other words, in the method of manufacturing electrodes, when there are two or more uncoated portions in the current collector, the number of shielding films 120 can be equal to or greater than the number of uncoated portions, and the shielding films 120 are respectively located at positions corresponding to all uncoated portions, thereby blocking at least a portion of infrared rays (or heat) from reaching all uncoated portions.

[0092] In one example of the method for manufacturing an electrode according to this application, the relationship between the width of the shielding film and the width of the uncoated portion present in the current collector can be defined as the A value according to the following general formula 1. Taking into account drying efficiency, the A value can be 1 or greater, 1.5 or greater, 2 or greater, 2.5 or greater, 3 or greater, or 3.5 or greater. In another example, the A value can also be 10 or less, 9.5 or less, 9 or less, 8.5 or less, or 8 or less. The A value according to the following general formula 1 can be within a range formed by appropriately selecting the upper and lower limits listed above.

[0093] [General Formula 1]

[0094] A = W 1 / W

[0095] In general formula 1, W1 represents the width of the shielding film, and W represents the width of the uncoated portion.

[0096] Furthermore, in one example of the method for manufacturing the electrode according to this application, the relationship between the distance between the shielding film and the infrared heat source and the distance between the current collector and the shielding film can be defined as the B value according to the following general formula 2. Taking into account drying efficiency, the B value can be 0.1 or greater, 0.25 or greater, 0.5 or greater, or 0.75 or greater. In another example, the B value can also be 5 or less, 4 or less, 3 or less, or 2 or less. The B value according to the following general formula 2 can be within a range formed by appropriately selecting the upper and lower limits listed above.

[0097] [General Formula 2]

[0098] B = H2 / H1

[0099] In general formula 2, H2 represents the distance between the shielding film and the infrared heat source, and H1 represents the distance between the current collector and the shielding film.

[0100] When the value of A according to general formula 1 and / or the value of B according to general formula 2 are respectively within the above range, the maximum infrared radiation (or heat) reaches the coated part, while the maximum infrared radiation (or heat) does not reach the uncoated part, thereby effectively drying the electrode slurry and preventing wrinkles or cracks in the electrode due to the difference in the coefficient of thermal expansion.

[0101] In the following description, the invention will be described with reference to examples and comparative examples, but the scope of the invention is not limited to what is given below.

[0102] Example 1

[0103] A negative electrode paste is coated onto a copper foil, which is a current collector made of a long sheet of metal foil, to form a pattern. At this time, three coated portions with a predetermined interval are formed in the pattern, thereby forming a total of four uncoated portions including both sides of the copper foil.

[0104] According to an example of this application, the infrared heat source module is positioned such that the movement direction of the frame extending in one direction of the infrared heat source module and the copper foil are perpendicular to each other. In this case, the copper foil is made of a long sheet of metal foil, allowing it to exhibit continuous movement, and the copper foil can be moved using unwinding rollers and winding rollers.

[0105] Meanwhile, the ratio (H2 / H1) of the distance between the shielding film and the infrared heat source (H2) to the distance (H1) between the copper foil and the shielding film of the infrared heat source module is set to about 1, the ratio (W1 / W) of the width of the shielding film (W1) to the width of the uncoated portion is set to about 4, and a stainless steel plate is used as the shielding film.

[0106] like Figure 7 As shown, the shielding film is coupled to the groove of the position-changing component mounted on the frame, and the shielding film is repositioned to the position corresponding to the uncoated portion of the copper foil, thereby allowing for drying. After drying, the drying rate is measured and... Figure 8 and Figure 9 The drying rate is shown in the figure.

[0107] Comparative Example 1

[0108] The drying process was carried out in the same manner as in Example 1, except that an infrared heat source module without a shielding film was used instead of the infrared heat source module of one example according to this application. After drying, the drying rate was measured and... Figure 8 and Figure 9 The drying rate is shown in the figure.

[0109] In Example 1 and Comparative Example 1, the drying rate was measured by the β-ray method, and the amount of moisture evaporation was calculated and measured using a web plate measuring instrument from Honeywell or Yokogawa.

[0110] Figure 8 and Figure 9 This is a view of the drying rate of the coated portion present in the current collectors measured in Example 1 and Comparative Example 1. Reference Figure 8The color of each location indicates the drying rate of the coated area. The white band representing areas where drying rate was not measured indicates uncoated areas. (Reference) Figure 9 This displays the drying rate of the coated portion at each location along the width of the copper foil; portions where the drying rate was not measured represent uncoated portions.

[0111] Reference Figure 8 and Figure 9 Example 1 showed uniform drying overall and exhibited a high drying rate of approximately 90% or higher. In contrast, Comparative Example 1 showed uneven drying, wrinkles on the electrodes, and a relatively low drying rate.

[0112] Figure 10 This is a view of an electrode with wrinkles formed during the drying process according to Comparative Example 1. (Reference) Figure 10 It can be confirmed that in Comparative Example 1, wrinkles were generated in the electrode due to the difference in the coefficient of thermal expansion between the coated and uncoated portions and the excessive drying of the uncoated portions.

[0113] Therefore, when using an infrared heat source module according to an example of this application, by minimizing the infrared radiation (or heat) reaching the uncoated portion and allowing the infrared radiation (or heat) to reach the coated portion, wrinkles or cracks can be prevented, and the drying efficiency of the electrode paste in the coated portion can be improved.

[0114] [Explanation of reference numerals in the attached figures]

[0115] 110: Frame 150: Position Changing Component

[0116] 111: Opening 160: Fixed component

[0117] 112: Support component C: Coated part

[0118] 120: Shielding film; N: Uncoated portion

[0119] 130: Infrared heat source

Claims

1. An infrared heat source module for drying electrode slurry, comprising: A frame that extends in one direction; At least one shielding membrane is installed on the frame; An infrared heat source mounted on the frame, wherein The shielding film is mounted on the frame and configured to be repositioned along one of the directions of the frame. The shielding film is configured to block at least a portion of the heat generated from the infrared heat source; as well as A position-changing component, mounted on the frame, is provided to allow for repositioning of the at least one shielding membrane. The position-changing component has a groove with a predetermined space, and a portion of the shielding film is inserted into the groove to couple the shielding film to the groove. The position-changing component further includes a track disposed within the groove, and a portion of the shielding film is coupled to the track. The position of the shielding film is changed by a moving device on the track. The infrared heat source emits light with a wavelength range of 3μm to 50μm. The frame includes an opening, and the at least one shielding membrane is located at one or more locations selected from the group consisting of the interior of the opening, the upper end of the opening, and the lower end of the opening. There are multiple shielding films, and each of the multiple shielding films is configured to be independently repositioned. The shielding film is continuously positioned at a location corresponding to the uncoated portion on the current collector, and even if the position of the uncoated portion changes while the infrared heat source module moves, the shielding film remains continuously positioned at a location corresponding to the changed position of the uncoated portion.

2. The infrared heat source module according to claim 1, wherein, The opening is configured to expose the heat generated by the infrared heat source to the outside.

3. The infrared heat source module according to claim 1 further includes a fixing component for fixing the infrared heat source to the frame.

4. The infrared heat source module according to claim 1 further includes a control device for automatically repositioning the shielding film.

5. A method for manufacturing an electrode, comprising: The electrode paste formed on the current collector is dried. The current collector includes a coated portion with the electrode paste and an uncoated portion without the electrode paste. In the case where the infrared heat source module according to claim 1 is placed on the current collector coated with the electrode paste, the drying is performed by applying heat from the infrared heat source module, and During the drying process, the shielding film of the infrared heat source module is positioned to block at least a portion of the heat applied from the infrared heat source of the infrared heat source module to the uncoated portion.

6. The method of manufacturing an electrode according to claim 5, wherein the drying is performed while the current collector on which the electrode slurry is formed is moved in one direction.

7. The method of manufacturing an electrode according to claim 6, wherein the infrared heat source module is movable in said one direction in which the current collector moves, or in a direction opposite to said one direction, and wherein, When the infrared heat source module is moved, the shielding film of the infrared heat source module is positioned to block at least a portion of the heat applied from the infrared heat source to the uncoated portion.

8. The method of manufacturing an electrode according to claim 5, wherein there are two or more uncoated portions, and wherein the shielding film of the infrared heat source module is arranged between each of the uncoated portions and the infrared heat source.

9. The method for manufacturing an electrode according to claim 5, wherein According to the following general formula 1, the value of A is from 1 to 10: [General Formula 1] A=W 1 / W in, W1 represents the width of the shielding film, and W represents the width of the uncoated portion.

10. The method for manufacturing an electrode according to claim 5, wherein According to the following general formula 2, the value of B is between 0.1 and 5: [General Formula 2] B=H2 / H1 in, H2 represents the distance between the shielding film and the infrared heat source, and H1 represents the distance between the current collector and the shielding film.

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