Device for electrode production

Abstract

Device for manufacturing an electrode, the device comprising: a hot air supply device that supplies hot air for drying a coating material applied to a coating substrate; a laser drying device that irradiates the coating material, which has passed through the hot air supply device, with a laser in order to dry the coating material; and a temperature measurement section that measures the temperature of the coating material that has passed through the laser drying device and transmits the measured temperature data to the laser drying device.

Description

TECHNICAL FIELD

[0001] The disclosures and embodiments disclosed in this document generally relate to an apparatus for manufacturing electrodes for secondary batteries. BACKGROUND

[0002] Unlike primary batteries, secondary batteries can be charged and discharged, making them suitable for devices in a variety of fields, such as digital cameras, mobile phones, laptops, hybrid cars, and electric vehicles. Recently, active research has been conducted on lithium secondary batteries with high energy density and discharge voltage among secondary batteries.

[0003] Generally, electrode plates for lithium secondary batteries are manufactured by a process in which an aluminum or copper sheet is coated with an active material for the positive or negative electrode and the active material is dried.

[0004] The coating and drying process has a significant impact on the productivity of secondary batteries. However, in the current state of the art, the active material of the electrode plate may be only partially dry after the drying process is completed for various reasons.

[0005] Therefore, a drying device is required to ensure uniform dryness.

[0006] The present disclosure may be implemented in some embodiments to provide an apparatus for manufacturing an electrode for a secondary battery capable of maintaining uniform dryness.

[0007] The apparatus for manufacturing an electrode for a secondary battery of the present disclosure can be widely applied in the technical field of secondary batteries such as pouch type secondary batteries and prismatic secondary batteries.

[0008] In some embodiments of the present disclosure, an apparatus for manufacturing an electrode includes: a hot air supply device that supplies hot air for drying a coating material applied to a coating substrate; a laser drying device that irradiates the coating material that has passed through the hot air supply device with a laser to dry the coating material; and a temperature measuring section that measures a temperature of the coating material that has passed through the laser drying device and transmits the measured temperature data to the laser drying device.

[0009] The apparatus may further include: a dryness measuring section that measures the dryness of the coating material by taking an image of the coating material that has passed through the hot air supply device, wherein the laser drying device can selectively dry the coating material based on the dryness measured by the dryness measuring section.

[0010] The dryness measurement section may include: a camera that captures the image of the coating material by irradiating the coating material with infrared or near-infrared rays; and an image analysis section that acquires dryness data of the coating material based on the image captured by the camera.

[0011] The image analysis section may divide an area in which the coating material has been imaged into a plurality of unit areas and collect the dryness data for each unit area.

[0012] The laser drying device can adjust and irradiate the power of the laser based on the dryness data for each unit area.

[0013] The laser drying apparatus may include a plurality of laser irradiation sections arranged in an array, and each of the laser irradiation sections may irradiate any one of the unit regions with a laser.

[0014] The laser drying device may include a vertical cavity surface-emitting (VCSE) laser.

[0015] The laser drying device can adjust the laser power for each unit area based on the temperature data transmitted from the temperature measuring section.

[0016] The apparatus may further include a coating section disposed at the front of the hot air supply device for applying the coating material in a slurry state to one or both sides of the coating substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Certain aspects, features and advantages of the present disclosure are explained in the following detailed description with reference to the accompanying drawings. Fig. 1 is a diagram schematically showing an apparatus for manufacturing an electrode according to an embodiment of the present disclosure; Fig. Figure 2 is an enlarged view of section A of Fig. 1; Fig. 3 is a plan view along direction B of Fig. 2; Fig. 4 is a perspective view of Fig. 3; Fig. 5 is a flowchart illustrating a method for manufacturing an electrode using an apparatus of the present disclosure; and Fig. 6 is a detailed flowchart of process S4 of Fig. 5. DETAILED DESCRIPTION

[0018] The present disclosure will be described in detail below with reference to the accompanying drawings. However, this is for illustrative purposes only, and the present disclosure is not limited to the specific embodiments described by way of example.

[0019] Fig. 1 is a diagram schematically showing an apparatus for manufacturing an electrode according to an embodiment of the present disclosure, Fig. Figure 2 is an enlarged view of section A of Fig. 1, Fig. 3 is a plan view along direction B of Fig. 2, and Fig. 4 is a perspective view of Fig. 3.

[0020] As in Fig. 1, the apparatus for manufacturing an electrode for a secondary battery according to an embodiment of the present disclosure may include an unwinder 10 that unwinds and feeds a coating substrate 5, a coating section 30 that applies a coating material 6 to a coating area of ​​the coating substrate 5, a first drying section 40 that dries the coating material 6, a second drying section 50 that selects an insufficiently dried section and performs additional drying, and a winder 20 that winds the coating substrate 5.

[0021] In the present embodiment, the coating substrate 5 may be provided in the form of a thin strip with a predetermined width and may refer to a thin metal film for forming an electrode of a secondary battery. For example, the coating substrate 5 may be a thin aluminum film for forming a positive electrode and a thin copper film for forming a negative electrode.

[0022] When the coating substrate 5 is fed from the unwinder 10, the coating material 6 is applied in the coating section 30, and the coating material can be dried while passing sequentially through the first drying section 40 and the second drying section 50, and then rewound in a winder 20. For this purpose, the electrode manufacturing apparatus of the present embodiment may include a transfer device that transports the coating substrate 5 in the above-mentioned order. The transfer device may include, for example, a plurality of rollers R that support and rotate the coating substrate 5.

[0023] The unwinder 10 can unwind the coating substrate 5 wound in the form of a roll and feed it to the coating section 30. As described above, the coating substrate 5 fed from the unwinder 10 can be a thin metal film, for example, a thin aluminum film or a thin copper film.

[0024] The coating section 30 can apply the coating material 6 to the coating substrate 5 supplied from the unwinder 10. For this purpose, the coating section 30 can include, but is not limited to, a slot die coater 32.

[0025] The coating material 6 may be an active material in slurry form, and the coating process can be performed in the same way for both the positive and negative electrodes. In the present embodiment, a case where the coating material 6 is applied to only one side of the coating substrate 5 is exemplified, but it is also possible to apply the coating material 6 to both sides of the coating substrate 5 if necessary.

[0026] The first drying section 40 may include at least one chamber through which the coating substrate 5 passes, and may remove moisture from the coating material 6 by supplying heat to the coating material 6 passing through the interior of the chamber. For this purpose, the first drying section 40 may include at least one of various heat sources 42. For example, the first drying section 40 may include a heater that supplies radiant heat to the coating material 6, such as a near-infrared lamp, or it may include a hot air supply device that supplies hot air at a specific temperature to the coating material 6. Furthermore, it may be configured to dry the coating material 6 by direct irradiation with a laser.Thus, the first drying section 40 of the present embodiment may use various known drying methods as long as it can effectively dry the coating material 6.

[0027] The heat source of the first drying section 40 can supply heat to the coating material 6 located inside the chamber. Therefore, the coating material 6 located inside the chamber can be dried to a certain extent, but in areas with relatively high humidity, the moisture may not be completely removed and may remain partially.

[0028] The second drying section 50 can selectively dry at least a portion of the coating material 6 on the coating substrate 5 that has passed through the first drying section 40. For example, the second drying section 50 can analyze a condition of the coating material 6 that has passed through the first drying section 40, and if there is a portion with residual moisture, i.e., a portion that has dried below a reference value set by an operator, the second drying section 50 can selectively / locally dry only the corresponding portion of the coating material 6. In this case, the reference value is a value set in advance by the operator, which can refer to a specific number of parts per million (PPM).In one embodiment, the second drying section 50 defines the PPM at which the moisture in the coating material 6 is sufficiently dried as the reference PPM, and may perform additional drying only for the portion having the reference PPM or more. Furthermore, in one embodiment, the second drying section 50 defines the coating material 6 in a slurry state supplied from the coating section 30 to a dryness level of 0% and the coating material 6 in a moisture state of 0 PPM to a dryness level of 100%. Based on this, the second drying section 50 may define the dryness level in % (e.g., 90%) effective for electrode production as the reference value.

[0029] For this purpose, the second drying section 50 may include a dryness measuring section 60, a laser drying device 70 and a temperature measuring section 80.

[0030] The dryness measuring section 60 can continuously measure the dryness of the coating material 6 of the coating substrate 5 that has passed through the first drying section 40. For this purpose, the dryness measuring section 60 can repeatedly perform a process of measuring the dryness of the coating material 6 for an area MA (hereinafter referred to as an imaging area) located below the dryness measuring section 60 and transmit the measurement results to the laser drying device 70.

[0031] The imaging range MA can be defined as an area that the dryness measuring section 60 can image at a given time.

[0032] The dryness measuring section 60 of the present embodiment can be arranged at a certain distance from the coating material 6 and can measure the dryness degree of the coating material 6 by taking an image of the coating material 6.

[0033] For example, the dryness measuring section 60 may include an imaging device 61 and an image analysis section 62, and after an image is captured by the imaging device 61, the captured image may be analyzed by the image analysis section 62 to measure dryness, based on which a low-dryness area may be selected.

[0034] In the present embodiment, the imaging device 61 may include a camera that irradiates infrared or near-infrared rays. In this case, the camera can image the coating material 6 by irradiating the coating material with infrared rays in a wavelength range that has high water absorption properties, thus obtaining an image in which regions are divided according to the degree of dryness. However, the present disclosure is not limited to this, and it is also possible to capture an image using a general camera as the imaging device 61 and analyze the dryness based on a color difference of the captured image.

[0035] The image analysis section 62 may obtain dryness data of the imaging area MA based on the image captured by the imaging device 61 and transmit it to the laser drying device 70. For example, the image analysis section 62 may divide the imaging area MA into a plurality of unit areas UA, calculate the dryness degree of each unit area UA, and generate dryness data.

[0036] The laser drying device 70 can adjust the power for each unit area UA based on the dryness data measured by the dryness measuring section 60 for each unit area and irradiate the coating material 6 with a laser. Accordingly, the laser drying device 70 can selectively / locally dry the coating material 6.

[0037] The laser drying apparatus 70 may include a plurality of laser irradiation sections 72. The plurality of laser irradiation sections 72 may be arranged in a one-dimensional or two-dimensional array, and each laser irradiation section 72 is arranged to face the coating material 6 to irradiate one of the unit regions UA with a laser. The laser drying apparatus 70 of the present embodiment may include, for example, a vertical cavity surface-emitting (VCSE) laser for laser irradiation.

[0038] In the laser drying apparatus 70 of the present embodiment configured as described above, each laser irradiation section 72 can independently irradiate a laser and can irradiate a laser with a different power. Therefore, a unit area UA in which the dryness degree is measured to be slightly low can be irradiated with a higher power laser, and a unit area UA in which the dryness degree is higher than the reference value can be irradiated with a lower power laser or not irradiated with a laser.

[0039] The laser drying apparatus 70 of the present embodiment can irradiate the entire imaging area MA with a laser simultaneously. However, the present disclosure is not limited to this, and it is also possible to partially irradiate the entire imaging area MA with a laser multiple times as needed.

[0040] The temperature measuring section 80 may be arranged at the rear of the laser drying device 70.

[0041] When removing moisture from the coating material 6 with the aid of a laser, the surface temperature of the coating material 6 can rise proportionally to the amount of heat that the laser supplies to the coating material 6, so that conversely, by measuring the surface temperature of the coating material 6, it can be determined whether the required amount of heat from the laser has been supplied to a specific area of ​​the coating material 6.

[0042] Accordingly, the temperature measuring section 80 of the present embodiment can measure the temperature of the coating material 6 that has passed through the laser drying device 70 and transmit the measured temperature data to the laser drying device 70. The laser drying device 70 can adjust the power of the laser based on the temperature data transmitted from the temperature measuring section 80.

[0043] In addition, if the temperature of the coating material 6 rises more than necessary, the properties of the coating material 6 or the coating substrate 5 may change, so that the temperature measuring section 80 can continuously determine whether the temperature of the coating material 6 is maintained within a normal range.

[0044] The temperature measuring section 80 may be arranged to face the coating material 6 at a certain distance from the coating material 6, and may include a plurality of temperature sensors for measuring the temperature of the coating material 6. The plurality of temperature sensors may be evenly distributed over an area where the temperature measuring section 80 faces the coating material 6. Accordingly, the temperature measuring section 80 may measure the temperature of the coating material 6 at different locations on the coating material 6. For example, the temperature measuring section 80 may be configured so that one infrared temperature sensor corresponds to a unit area, and thus the plurality of temperature sensors may be configured so that each detects the temperature of a different unit area. However, the present embodiment is not limited to this.

[0045] The winder 20 can wind the coating substrate 5 into a rolled state after it has passed through the second drying section 50. As long as the winder 20 stably winds the coating substrate 5, various known devices can be used.

[0046] If the dried coating substrate 5 is immediately introduced into a subsequent process, the winder 20 can be omitted.

[0047] Next, a manufacturing process using the Fig. 1 for producing an electrode for a secondary battery is described.

[0048] Fig. 5 is a flowchart of a method for manufacturing an electrode using an apparatus of the present disclosure, and Fig. 6 is a detailed flowchart of process S4 of Fig. 5.

[0049] With reference to Fig. 5 and Fig. 6, in the method for producing an electrode for a secondary battery, the unwinder 10 may first unwind the coating substrate 5 wound in roll form and feed it to the coating section 30.

[0050] The coating section 30 can coat the coating substrate 5 supplied from the unwinder 10 with the coating material 6 (S2). The coating material 6 can be an active material in a slurry state that can be applied to one or both sides of the coating substrate 5. When the application of the coating material 6 in the coating section 30 is completed, the coating material 6 is primarily dried in the first drying section 40 (S3). Furthermore, the coating substrate 5, after passing through the first drying section 40, can enter the second drying section 50.

[0051] In the second drying section 50, secondary drying is performed to selectively dry an insufficiently dried portion of the coating material 6 for which the primary drying has been completed (S4).

[0052] First, the imaging device 61 of the dryness measurement section 60 captures an image of the coating material 6 located in the imaging area MA. Further, based on the image captured by the imaging device 61, the image analysis section 62 may divide the imaging area MA into a plurality of unit areas UA and calculate the dryness degree of each unit area UA to generate dryness data (S41).

[0053] Thereafter, the image analysis section 62 may transmit the dryness data of the imaging area MA to the laser drying device.

[0054] This process can be repeated according to the movement of the coating substrate 5.

[0055] Subsequently, the laser drying device 70 may irradiate each unit area UA with a laser to secondarily dry the coating material 6.

[0056] The laser drying device 70 can adjust the laser power for each unit area UA based on the information transmitted from the dryness measuring section 60, that is, the dryness data for each unit area UA (S42). Furthermore, when the coating substrate 5 is moving and the imaging area MA in which the dryness was measured by the dryness measuring section 60 is located within the laser irradiation area, each laser irradiation section 72 can irradiate the corresponding unit area UA with a laser at a set power to remove the moisture from each unit area UA (S43).

[0057] In the laser drying apparatus 70 of the present embodiment, one laser irradiation section 72 may be responsible for a unit area UA, or a plurality of laser irradiation sections 72 may be grouped for each unit area UA to be responsible for a corresponding unit area UA. This may be changed according to the size of the unit area UA or the area that each laser irradiation section 72 can irradiate.

[0058] In this method, the laser drying device 70 may irradiate a unit area UA whose dryness degree is measured to be relatively low with a high-power laser, and a unit area UA whose dryness degree is measured to be relatively high with a low-power laser. Furthermore, the laser drying device 70 may not irradiate a unit area UA determined to be completely dried with a laser. For example, if the above-mentioned reference value is 90% dryness, in this method, a unit area UA with a dryness degree of 90% or more is not irradiated with a laser, a unit area UA with a dryness degree of 50% is irradiated with 50% of the maximum laser power, and a unit area UA with a dryness degree of 80% may be irradiated with 20% of the maximum laser power.

[0059] After the coating material 6 has passed through the laser drying device 70, it can pass through the temperature measuring section 80, which is located at the rear of the laser drying device 70.

[0060] The temperature measuring section 80 can measure the temperature of the coating material 6 that has passed through the laser drying device 70 and transmit the measured temperature data to the laser drying device 70 (S44). Accordingly, the laser drying device 70 can adjust the power of the laser for each unit area UA based on the temperature data transmitted from the temperature measuring section 80 (S45). For example, if the temperature indicated in a certain unit area UA is higher than the preset reference temperature, the laser drying device 70 can reduce the power of the laser irradiated to the unit area UA.

[0061] When the coating material 6 is completely dried by this process, the coating substrate 5 can be wound into a roll by the winder 20 (S5).

[0062] In the apparatus for manufacturing an electrode for a secondary battery according to the present embodiment configured as described above, even if there is a portion that is not sufficiently dried in the first drying section 40, the corresponding portion can be selected and additionally dried in the second drying section 50. Therefore, the dryness of the electrode can be uniformly maintained, and electrode defects due to insufficient drying can be prevented.

[0063] Furthermore, when the first drying section 40 is operated according to the prior art, the system of the present embodiment can be implemented by adding only the second drying section 50 between the first drying section 40 and the winder 20 without replacing the first drying section 40, thereby minimizing the cost of replacing the equipment.

[0064] Meanwhile, the imaging device 61 of the present embodiment can image the coating substrate 5 with the camera and recognize a width of the coating material 6 applied to the coating substrate 5, a coating state of the coating material 6, and the like based on the captured image.

[0065] Furthermore, in the present embodiment, for example, the dryness measuring section 60 is arranged at the front of the laser drying device 70, but the dryness measuring section 60 may also be arranged at the rear of the laser drying device 70 if necessary. For example, if the dryness measuring section 60 is arranged at the rear of the laser drying device 70, the dryness measuring section 60 can check the dryness of the coating material 6 that has passed through the laser drying device 70 and transmit dryness data to the laser drying device 70, and the laser drying device 70 can adjust the power based on the received dryness data.

[0066] The contents described above are merely an example of the application of the principles of the present disclosure, and other components may be further incorporated without departing from the scope of the present disclosure. For example, in the above-mentioned embodiments, the case where the coating material is applied to only one side of the coating substrate is cited. However, the present disclosure is not limited to this, and it is also possible to coat both sides of the coating substrate with a coating material. In this case, the dryness measuring section and the laser drying device may be arranged on both sides of the coating substrate.

[0067] Only specific examples of implementations of particular embodiments are described. Variations, improvements, and extensions of the disclosed embodiments and other embodiments may be made based on the disclosure of this document.

Claims

[1] Apparatus for producing an electrode, the apparatus comprising: a hot air supply device that supplies hot air for drying a coating material applied to a coating substrate; a laser drying device that irradiates the coating material that has passed through the hot air supply device with a laser to dry the coating material; and a temperature measuring section that measures the temperature of the coating material that has passed through the laser drying device and transmits the measured temperature data to the laser drying device. [2] The device of claim 1, further comprising: a dryness measuring section that measures the dryness of the coating material by taking an image of the coating material that has passed through the hot air supply device, wherein the laser drying device selectively dries the coating material based on the dryness measured by the dryness measuring section. [3] The apparatus according to claim 2, wherein the dryness measuring section includes: a camera that captures the image of the coating material by irradiating the coating material with infrared or near-infrared rays; and an image analysis section that collects dryness data of the coating material based on the image captured by the camera. [4] The apparatus according to claim 3, wherein the image analysis section divides an area in which the coating material has been imaged into a plurality of unit areas and acquires the dryness data for each unit area. [5] The apparatus according to claim 4, wherein the laser drying device adjusts and irradiates a power of the laser based on the dryness data for each unit area. [6] Device according to claim 5, wherein the laser drying device includes a plurality of laser irradiation sections arranged in an array, and each of the laser irradiation sections irradiates one of the unit areas with a laser. [7] The apparatus of claim 6, wherein the laser drying device includes a vertical cavity surface emitting laser (VCSE). [8] The apparatus according to claim 5, wherein the laser drying device adjusts a laser power for each unit area based on temperature data transmitted from the temperature measuring section. [9] The apparatus of claim 1, further comprising a coating section disposed at the front of the hot air supply device and applying the coating material in a slurry state to one or both sides of the coating substrate.

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