Electrode drying equipment and electrode drying system including the same

Abstract

According to an exemplary embodiment, a drying system is provided that includes an electrode drying facility and a dehumidifier. The electrode device is configured to dry electrodes. The drying chamber includes a drying chamber, a plurality of forced air supply devices installed on an upper surface of the drying chamber, and a plurality of exhaust ports installed on a rear surface of the drying chamber. The dehumidifier is connected to the forced air supply device and configured to generate dry air that is provided to the drying chamber via the forced air supply device. The dry air generated by the dehumidifier is provided directly to the forced air supply device.

Description

[Technical Field]

[0001] The present invention relates to an electrode drying system. More specifically, the present invention relates to an electrode drying apparatus including a forced air supply device and an electrode drying system including the same. This application claims the benefit of Korean application No. 10-2023-0003506 filed on 10 January 2023 and Korean application No. 10-2024-0000998 filed on 3 January 2024, which are herein by reference in their entirety. [Background technology]

[0002] Unlike primary batteries, rechargeable batteries can be charged and discharged multiple times. Rechargeable batteries are widely used as an energy source for a variety of wireless devices such as handsets, laptops, and wireless vacuum cleaners. In recent years, improvements in energy density and economies of scale have dramatically reduced the unit cost of manufacturing electric-powered vehicles (HEVs) and battery electric vehicles (BEVs), and as the driving range of BEVs has increased to the same level as fuel-powered vehicles, the main use of rechargeable batteries is shifting from mobile devices to mobility.

[0003] Rechargeable batteries are classified into lithium-ion batteries, lithium-ion polymer batteries, and lithium polymer batteries based on the configuration of their electrodes and electrolyte. Lithium-ion polymer batteries are easier to manufacture due to their lower risk of electrolyte leakage, and their market share within rechargeable batteries is increasing.

[0004] Rechargeable batteries are classified according to the shape of their battery case into cylindrical batteries, where the electrode assembly is housed in a cylindrical metal can; rectangular batteries, where the electrode assembly is housed in a rectangular metal can; and pouch batteries, where the electrode assembly is housed in a pouch case made of aluminum laminate sheet.

[0005] The electrode assembly housed in the battery case includes a positive electrode, a negative electrode, and a separator membrane interposed between the positive and negative electrodes. Electrode assemblies are classified into jelly roll type and stack type depending on their assembly configuration. The jelly roll type consists of a rolled assembly of the positive electrode, negative electrode, and the separator membrane interposed between them. The stack type includes multiple positive electrodes, multiple negative electrodes, and multiple separator membranes interposed between them, stacked sequentially.

[0006] The electrode drying process involves coating sheet-shaped positive and negative electrode current collectors with active material and then removing moisture from the positive and negative electrodes before separating them. Uniform drying across the entire electrode sheet can improve the yield and reliability of secondary batteries. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The technical concept of this invention aims to solve the problem of providing an electrode drying apparatus and an electrode drying system including the same that have improved reliability. [Means for solving the problem]

[0008] According to an exemplary embodiment of the present invention for solving the above-mentioned problems, a drying system including an electrode drying device and a dehumidifier is provided.

[0009] The electrode device described above includes a drying chamber, a plurality of forced air supply devices installed on the upper surface of the drying chamber, and a plurality of exhaust ports installed on the rear surface of the drying chamber, and is configured to dry the electrodes.

[0010] The dehumidifier is connected to the forced air supply device and is configured to generate dry air that is supplied to the drying chamber via the forced air supply device.

[0011] The dry air generated by the dehumidifier is supplied directly to the forced air supply device.

[0012] The electrode drying system further includes a plurality of air supply pipes connected to the dehumidifier, and each of the plurality of air supply pipes is connected to a corresponding one of the plurality of forced air supply devices.

[0013] The electrode drying system further includes a plurality of air supply fans installed in each of the plurality of air supply pipes, and each of the plurality of air supply fans is configured to provide a driving force for transmitting the dry air through each of the plurality of air supply pipes.

[0014] The electrode drying equipment further includes a plurality of first rollers and a plurality of second rollers arranged in the drying chamber and configured to support the electrodes. Each of the plurality of first rollers is spaced from the upper surface of the drying chamber with the plurality of second rollers interposed therebetween.

[0015] The plurality of second rollers are interposed between the plurality of first rollers in the longitudinal direction of the electrodes.

[0016] The plurality of first rollers and the plurality of second rollers are configured to support the electrodes such that the middle portion of the electrodes rises compared to the edge portions of the electrodes.

[0017] The drying chamber further includes a bottom surface on the opposite side of the upper surface of the drying chamber. The distance between each of the plurality of exhaust ports and the upper surface of the drying chamber is smaller than the distance between each of the plurality of exhaust ports and the bottom surface of the drying chamber.

[0018] Each of the plurality of forced air supply devices does not overlap in a direction perpendicular to the upper surface of the electrode and the drying chamber.

[0019] Each of the plurality of forced air supply devices is interposed between the electrode and the front surface of the drying chamber, and the front surface of the drying chamber is on the opposite side of the rear surface of the drying chamber.

[0020] Each of the plurality of forced air supply devices includes any one of an airspeed meter, a thermometer, a hygrometer, an electric damper, and a duct.

[0021] The electrode drying system further includes a plurality of manual air supply devices installed on the front surface of the drying chamber, and the front surface of the drying chamber is on the opposite side of the rear surface of the drying chamber.

[0022] Each of the manual air supply devices is not connected to the dehumidifier.

[0023] According to an exemplary embodiment, an electrode drying facility is provided. The electrode drying facility includes a drying chamber, a plurality of forced air supply devices installed on the upper surface of the drying chamber, and a plurality of exhaust ports installed on the rear surface of the drying chamber, and each of the plurality of forced air supply devices is spaced apart from the electrodes loaded in the drying chamber in a direction parallel to the upper surface of the drying chamber.

[0024] Each of the plurality of air supply devices does not overlap with the electrodes.

[0025] The distance between each of the plurality of forced air supply devices and the front surface of the drying chamber is smaller than the distance between each of the plurality of air supply devices and the rear surface of the drying chamber, and the front surface of the drying chamber is on the opposite side of the rear surface of the drying chamber.

[0026] Each of the plurality of forced air supply devices is interposed between the electrodes and the front surface of the drying chamber in a first direction parallel to the upper surface of the drying chamber.

[0027] The electrode drying facility further includes a plurality of manual air supply devices configured to supply dry air to the drying chamber, and the plurality of manual air supply devices are on the front surface of the drying chamber.

[0028] The above-mentioned forced air supply device is directly connected via an air supply pipe to a dehumidifier configured to generate dry air.

[0029] The above manual air supply device is not connected to the above dehumidifier.

[0030] The distance between each of the multiple exhaust ports and the upper surface of the drying chamber is smaller than the distance between each of the multiple exhaust ports and the lower surface of the drying chamber, and the lower surface of the drying chamber is on the opposite side of the upper surface of the drying chamber.

[0031] According to an exemplary embodiment, an electrode drying apparatus is provided. The electrode drying apparatus includes a drying chamber, a plurality of forced air supply devices installed on the lower surface of the drying chamber, and a plurality of exhaust ports installed on the rear surface of the drying chamber, wherein each of the plurality of forced air supply devices is spaced away from the electrodes loaded into the drying chamber in a direction parallel to the lower surface of the drying chamber.

[0032] The distance between each of the above-mentioned multiple forced air supply devices and the front surface of the drying chamber is smaller than the distance between each of the above-mentioned multiple air supply devices and the rear surface of the drying chamber, and the front surface of the drying chamber is on the opposite side of the rear surface of the drying chamber.

[0033] Each of the above-mentioned multiple forced air supply devices is interposed between the electrode and the front surface of the drying chamber in a first direction parallel to the rear surface of the drying chamber.

[0034] The electrode drying apparatus further includes a plurality of manual air supply devices configured to supply dry air to the drying chamber, and the plurality of manual air supply devices are located on the front of the drying chamber.

[0035] The above-mentioned forced air supply device is directly connected by air supply piping to a dehumidifier configured to generate dry air.

[0036] The above manual air supply device is not connected to the above dehumidifier.

[0037] The distance between each of the multiple exhaust ports and the lower surface of the drying chamber is smaller than the distance between each of the multiple exhaust ports and the upper surface of the drying chamber, and the upper surface of the drying chamber is on the opposite side of the lower surface of the drying chamber. [Effects of the Invention]

[0038] According to exemplary embodiments of the present invention, the moisture mass fraction in the drying chamber can be reduced, thereby mitigating the generation of vortices and turbulence within the drying chamber. This can improve the uniformity and reliability of the drying process by the electrode drying system.

[0039] The effects that can be obtained from exemplary embodiments of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly derived and understood by a person of ordinary skill in the art to which the exemplary embodiments of this disclosure belong, from the following description. That is, unintended effects associated with carrying out exemplary embodiments of this disclosure can also be derived by a person of ordinary skill in the art from exemplary embodiments of this disclosure. [Brief explanation of the drawing]

[0040] [Figure 1] This is a drawing illustrating an electrode drying system according to an exemplary embodiment. [Figure 2] This is a drawing illustrating an electrode drying apparatus according to an exemplary embodiment. [Figure 3] This is a drawing illustrating an electrode drying apparatus according to an exemplary embodiment. [Figure 4] These drawings illustrate an electrode drying apparatus according to another exemplary embodiment. [Figure 5] These drawings illustrate an electrode drying apparatus according to another exemplary embodiment. [Figure 6]This is a flowchart illustrating an electrode manufacturing method according to an exemplary embodiment. [Modes for carrying out the invention]

[0041] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Before that, however, the terms and words used herein and in the claims shall not be construed to be limited to their usual or dictionary meanings, but rather to be interpreted as meanings and concepts consistent with the technical spirit of the present invention, based on the principle that an inventor may appropriately define the concepts of terms in order to best describe his own invention.

[0042] Therefore, the embodiments described herein and the configurations shown in the drawings represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention; there are various equivalents and modifications that can substitute for them at the time of filing.

[0043] Furthermore, in describing the present invention, if it is determined that a specific description of a related known configuration or function would likely obscure the gist of the invention, such detailed description will be omitted.

[0044] Since embodiments of the present invention are provided to more fully explain the invention to an ordinary person, the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect the actual sizes and proportions.

[0045] Figure 1 is a diagram illustrating an exemplary embodiment of an electrode drying system 10.

[0046] Referring to Figure 1, the electrode drying system 10 may include an electrode drying device 100, a dehumidifier 200, multiple supply air pipes 210, multiple supply air fans 220, multiple exhaust pipes 310, and multiple exhaust fans 320.

[0047] The electrode drying system 10 may be configured to perform a drying process for electrodes EL. Electrodes EL may be used for the manufacture of secondary batteries. Electrodes EL may be a positive electrode or a negative electrode. The positive electrode includes a positive electrode current collector and a positive electrode active material coated on the positive electrode current collector, and the negative electrode includes a negative electrode current collector and a negative electrode active material coated on the negative electrode current collector.

[0048] The drying process may include loading the electrode EL into the drying chamber 110 and then supplying dry air into the drying chamber 110. The drying process may be carried out based on temperature control and dew point control inside the drying chamber 110. The drying process may include maintaining the temperature and dew point inside the drying chamber 110 within a set range based on measurements from temperature sensors and dew point sensors installed inside the drying chamber 110. As an example, the dew point inside the drying chamber 110 may be maintained at or below approximately -70°C. In the drying process, the dew point inside the drying chamber 110 may be in the range of approximately -20°C to approximately -70°C.

[0049] The dehumidifier 200 may be configured to produce dry air by removing pollutants and moisture from the outside air. The dry air produced by the dehumidifier 200 may be distributed to each part and element of the electrode drying system 10 as needed. The electrode drying system 10 may include an Environment Control Unit, which can control the atmosphere inside the electrode drying system 10 using the dry air produced by the dehumidifier 200.

[0050] The dehumidifier 200 may be connected to a plurality of forced air supply devices 120 of the electrode drying equipment 100 by a plurality of air supply pipes 210. According to an exemplary embodiment, the plurality of forced air supply devices 120 may be directly connected to the dehumidifier 200 by a plurality of air supply pipes 210. Each of the plurality of air supply pipes 210 may be connected to a corresponding one of the dehumidifier 200 and the plurality of forced air supply devices 120.

[0051] In Figure 1, the connections between the multiple air supply pipes 210 and the multiple exhaust pipes 310 are indicated by dashed lines.

[0052] Each of the multiple air supply pipes 210 can provide a passage for the movement of dry air generated by the dehumidifier 200. The dry air generated by the dehumidifier 200 can be supplied to multiple forced air supply devices 120 via the multiple air supply pipes 210. This improves the uniformity and reliability of the drying process, as the dry air generated by the dehumidifier 200 is immediately supplied to the drying chamber 110 via the forced air supply devices 120, even when a source of moisture, such as a worker, is located inside the electrode drying system 10.

[0053] Multiple supply fans 220 may be installed in multiple supply air pipes 210. Each of the supply fans 220 may be configured to provide a driving force for dry air to move through the multiple supply air pipes 210. Each of the supply fans 220 may be configured to regulate the velocity of the dry air flow through the multiple supply air pipes 210.

[0054] The air inside the drying chamber 110 can be discharged through a plurality of exhaust ports 130. The air inside the drying chamber 110 may have a higher humidity than the dry air supplied by the plurality of forced air supply devices 120 as the drying process progresses. The plurality of exhaust ports 130 can discharge the air inside the drying chamber 110 so that the atmosphere inside the drying chamber 110 (e.g., humidity, temperature, and pressure) is kept constant.

[0055] Each of the multiple exhaust ports 130 can be connected to each of the multiple exhaust pipes 310. The multiple exhaust pipes 310 can provide a path for discharging air from inside the drying chamber 110.

[0056] Multiple exhaust fans 320 may be installed in each of the multiple exhaust pipes 310. Each of the multiple exhaust fans 320 may provide the driving force to exhaust the air from the drying chamber 110 through the multiple exhaust pipes 310. Each of the multiple exhaust fans 320 may adjust the velocity of the airflow out of the multiple exhaust ports 130.

[0057] Multiple manual air supply devices 140 of the electrode drying equipment 100 may be configured to supply dry air to the inside of the drying chamber 110. The multiple manual air supply devices 140 can supply dry air distributed from the dehumidifier 200 to the electrode drying system 10 to the inside of the drying chamber 110.

[0058] Multiple manual air supply devices 140 may not be connected to the dehumidifier 200. The electrode drying system 10 may not include piping connecting the multiple manual air supply devices 140 to the dehumidifier 200. Multiple manual air supply devices 140 may supply dry air into the drying chamber 110 by suction force provided through multiple exhaust ports 130.

[0059] The multiple manual air supply devices 140 may have an openable and closable structure. When the multiple manual air supply devices 140 are closed, the airflow through the multiple manual air supply devices 140 may be blocked, and as a result, the multiple manual air supply devices 140 may not supply dry air to the drying chamber 110. When the multiple manual air supply devices 140 are open, the airflow through the multiple manual air supply devices 140 may be allowed, and as a result, the multiple manual air supply devices 140 may supply dry air to the drying chamber 110.

[0060] Figures 2 and 3 are diagrams illustrating an electrode drying apparatus 100 according to an exemplary embodiment. More specifically, Figure 2 is a view of the electrode drying apparatus 100 from the front 110F of the drying chamber 110, and Figure 3 is a view of the electrode drying apparatus 100 from the top 110T of the drying chamber 110.

[0061] Referring to Figures 2 and 3, the electrode drying equipment 100 may include, in addition to the drying chamber 110, multiple forced air supply devices 120, multiple exhaust ports 130, and multiple manual air supply devices 140 described above, multiple first rollers 151 and multiple second rollers 152.

[0062] The drying chamber 110 can provide a space for the drying process. The drying chamber 110 can isolate its internal space from the outside. The inside of the drying chamber 110 may have controlled temperature, humidity, and pressure, thereby enabling a uniform drying process across the entire surface of the electrode EL.

[0063] The drying chamber 110 may include a front surface 110F, a rear surface 110R, a bottom surface 110B, a top surface 110T, a first side surface 110S1, and a second side surface 110S2. Hereinafter, the direction substantially perpendicular to the front surface 110F and the rear surface 110R is defined as the X direction, the direction substantially perpendicular to the first side surface 110S1 and the second side surface 110S2 is defined as the Y direction, and the direction substantially perpendicular to the bottom surface 110B and the top surface 110T is defined as the Z direction. The X, Y, and Z directions may be substantially perpendicular to each other. Unless otherwise defined, the definitions of the X, Y, and Z directions in the following drawings are the same as those described above.

[0064] The bottom surface 110B may face the bottom of the space in which the drying chamber 110 is installed. The top surface 110T may be on the opposite side of the bottom surface 110B. The top surface 110T may be spaced away from the bottom of the space in which the drying chamber 110 is installed, with the bottom surface 110B in between. Multiple forced air supply devices 120 may be installed on the top surface 110T.

[0065] Each of the multiple forced air supply devices 120 may include one of the following: an anemometer, a thermometer, a hygrometer, an electric damper, and a duct. The anemometer may be configured to measure the velocity of the dry air flowing through each of the multiple forced air supply devices 120. The thermometer may be configured to measure the temperature of the dry air flowing through each of the forced air supply devices 120. The hygrometer may be configured to measure the absolute humidity of the dry air flowing through each of the forced air supply devices 120. The hygrometer may also measure the relative humidity of the dry air flowing through each of the forced air supply devices 120. The electric damper may be configured to adjust the flow rate of the dry air flowing through each of the forced air supply devices 120. The duct may be configured to adjust the direction of the dry air discharged through each of the forced air supply devices 120.

[0066] Based on the readings of the anemometer, thermometer, and hygrometer of each of the multiple forced air supply devices 120, signals can be generated to control each of the multiple forced air supply devices 120. For example, based on the readings of the thermometers of each of the multiple forced air supply devices 120, signals can be generated to control a heater installed in any one of the dehumidifier 200 (see Figure 1) and the multiple air supply pipes 210 (see Figure 1). As another example, based on the readings of the anemometers of each of the multiple forced air supply devices 120, signals can be generated to control the output of any one of the multiple air supply fans 220. As yet another example, based on the readings of the hygrometers of each of the multiple forced air supply devices 120, signals can be generated to control the operation of the dehumidifier 200 (see Figure 1).

[0067] The control signals described above may be generated based on, but are not limited to, negative feedback to ensure that the process parameters of the drying chamber 110 remain within the normal range. The electric damper and duct may operate based on the control signals described above and any additional control signals.

[0068] Multiple exhaust ports 130 may be installed on the rear surface 110R. The rear surface 110R may be connected to the top surface 110T and the bottom surface 110B. The rear surface 110R may be interposed between the top surface 110T and the bottom surface 110B. Multiple exhaust ports 130 may be further adjacent to the top surface 110T than to the bottom surface 110B. The distance d1 between each of the multiple exhaust ports 130 and the top surface 110T may be smaller than the distance d2 between each of the multiple exhaust ports 130 and the bottom surface 110B.

[0069] Multiple manual air supply devices 140 may be installed on the front 110F. The front 110F may be on the opposite side of the rear 110R. The front 110F may be interposed between the top 110T and the bottom 110B. Although not explicitly shown, the front 110F may include one or more doors for operator work. Operator work may include maintenance of the internal elements of the drying chamber 110, loading and unloading of electrodes EL, and stopping work when a warning signal is generated.

[0070] The first side surface 110S1 and the second side surface 110S2 can each be connected to the bottom surface 110B, the top surface 110T, the front surface 110F, and the rear surface 110R. This allows the first side surface 110S1 and the second side surface 110S2, the bottom surface 110B, the top surface 110T, the front surface 110F, and the rear surface 110R to form a closed space for the drying process.

[0071] Multiple first rollers 151 and multiple second rollers 152 may be arranged inside the drying chamber 110. Multiple first rollers 151 may be adjacent to the bottom surface 110B, and multiple second rollers 152 may be adjacent to the top surface 110T. Each of the multiple first rollers 151 may be spaced away from the top surface 110T with multiple second rollers 152 in between. Each of the multiple second rollers 152 may be spaced away from the bottom surface 110B with multiple first rollers 151 in between.

[0072] Multiple first rollers 151 and second rollers 152 may be configured to support the electrode EL. Multiple first rollers 151 and second rollers 152 may be configured to move the electrode EL. By the rotation of the multiple first rollers 151 and second rollers 152, the electrode EL may be moved from the first side surface 110S1 to the second side surface 110S2, or from the second side surface 110S2 to the first side surface 110S1.

[0073] In this example, multiple second rollers 152 may be interposed between multiple first rollers 151 in the Y direction. This allows the middle portion of the electrode EL inside the drying chamber 110 to be elevated compared to the edge portion of the electrode EL. Here, the middle portion of the electrode EL refers to the portion of the electrode EL between the multiple second rollers 152, and the edge portion of the electrode EL refers to the portion of the electrode EL between the multiple first rollers 151 and the first side surface 110S1 and the second side surface 110S2.

[0074] The Y direction may be substantially parallel to the longitudinal direction in which the intermediate and edge portions of electrode EL extend, and thus the Y direction may also be referred to as the longitudinal direction. Furthermore, the Y direction may be substantially parallel to the direction in which the intermediate and edge portions of electrode EL move, and thus the Y direction may also be referred to as the direction of movement of electrode EL.

[0075] The X direction can be substantially parallel to the width direction of electrode EL, and thus the X direction can also be referred to as the width direction of electrode EL. The Z direction can also be referred to as the height direction.

[0076] According to exemplary embodiments, the forced air supply device 120 may not overlap with the electrode EL in the Z direction. According to exemplary embodiments, the forced air supply device 120 may be spaced away from the electrode EL in the X direction. According to exemplary embodiments, the forced air supply device 120 may be interposed between the electrode EL and the front surface 110F in the X direction. According to exemplary embodiments, the forced air supply device 120 may not overlap with the surfaces of the first roller 151 and the second roller 152 that support the electrode EL in the Z direction. According to exemplary embodiments, the forced air supply device 120 may be spaced away from the surfaces of the first roller 151 and the second roller 152 that support the electrode EL in the X direction. According to exemplary embodiments, the forced air supply device 120 may be interposed between the surfaces of the first roller 151 and the second roller 152 that support the electrode EL and the front surface 110F in the X direction. This can prevent the dry air introduced through the forced air supply device 120 from being directly sprayed onto specific parts of the electrode EL, thereby improving the uniformity of the drying process.

[0077] In experimental examples, when the middle portion of the electrode EL loaded into the drying chamber 110 rises compared to the edge portion of the electrode EL, the forced air supply device 120 is positioned adjacent to the upper surface 110T of the chamber, and it was confirmed that the vortex and turbulence inside the drying chamber 110 are reduced. Furthermore, in experimental examples, it was confirmed that the provision of the forced air supply device 120 increased the amount of moisture evaporated in the drying chamber 110 by approximately 30% compared to conventional electrode drying equipment. This confirmed that the electrode drying equipment 100 and the electrode drying system 10 including it (see Figure 1) according to the exemplary embodiment provide improved uniformity and efficiency of the drying process.

[0078] Figure 4 is a diagram illustrating an electrode drying apparatus 101 according to another exemplary embodiment. More specifically, Figure 4 shows the portion of the electrode drying apparatus 101 corresponding to Figure 2.

[0079] Referring to Figure 4, the electrode drying equipment 101 may include a drying chamber 110, a plurality of forced air supply devices 121, a plurality of exhaust ports 131, a plurality of manual air supply devices 140, a plurality of first rollers 151, and a plurality of second rollers 152.

[0080] The drying chamber 110 and the multiple manual air supply devices 140 are substantially the same as those described with reference to Figure 1, so a redundant explanation of them will be omitted.

[0081] Multiple forced air supply devices 121 may be installed on the bottom surface 110B. Each of the multiple forced air supply devices 120 may include one of an anemometer, thermometer, hygrometer, electric damper, and duct. The operation and function of the anemometer, thermometer, hygrometer, electric damper, and duct are substantially the same as those described with reference to Figures 2 and 3.

[0082] Multiple exhaust ports 131 may be installed on the rear surface 110R. Multiple exhaust ports 131 may be further adjacent to the bottom surface 110B than to the top surface 110T. The distance d1' between each of the multiple exhaust ports 131 and the top surface 110T may be greater than the distance d2' between each of the multiple exhaust ports 131 and the bottom surface 110B.

[0083] In this example, in contrast to the configuration shown in Figure 2, the multiple first rollers 151 may be interposed between the multiple second rollers 152 in the Y direction. This allows the edge portion of the electrode EL inside the drying chamber 110 to be higher than the middle portion of the electrode EL. Here, the middle portion of the electrode EL refers to the portion of the electrode EL between the multiple first rollers 151, and the edge portion of the electrode EL refers to the portion of the electrode EL between the multiple second rollers 152 and the first side surface 110S1 and the second side surface 110S2.

[0084] According to exemplary embodiments, the forced air supply device 121 may not overlap with the electrode EL in the Z direction. According to exemplary embodiments, the forced air supply device 121 may be spaced away from the electrode EL in the X direction. According to exemplary embodiments, the forced air supply device 121 may be interposed between the electrode EL and the front surface 110F in the X direction. According to exemplary embodiments, the forced air supply device 121 may not overlap with the surfaces of the first roller 151 and the second roller 152 that support the electrode EL in the Z direction. According to exemplary embodiments, the forced air supply device 121 may be spaced away from the surfaces of the first roller 151 and the second roller 152 that support the electrode EL in the X direction. According to exemplary embodiments, the forced air supply device 121 may be interposed between the surfaces of the first roller 151 and the second roller 152 that support the electrode EL and the front surface 110F in the X direction. This can prevent the dry air introduced through the forced air supply device 121 from being directly sprayed onto the electrode EL, thereby improving the uniformity of the drying process.

[0085] Figure 5 is a diagram illustrating an electrode drying apparatus 102 according to another exemplary embodiment. More specifically, Figure 5 shows the portion of the electrode drying apparatus 102 corresponding to Figure 2.

[0086] Referring to Figure 5, the electrode drying equipment 102 may include a drying chamber 110, a plurality of forced air supply devices 120, 121, a plurality of exhaust ports 130, 131, a plurality of manual air supply devices 140, a plurality of first rollers 151, and a plurality of second rollers 152.

[0087] The drying chamber 110 and the multiple manual air supply devices 140 are substantially the same as those described with reference to Figure 1, so a redundant explanation of them will be omitted.

[0088] Multiple forced air supply devices 120 may be installed on the top surface 110T, and multiple forced air supply devices 121 may be installed on the bottom surface 110B. In Figure 5, two forced air supply devices 120 are shown installed on the top surface 110T and one forced air supply device 121 is shown installed on the bottom surface 110B, but this is for the sake of explanation, and the number and arrangement of forced air supply devices 120 and 121 may be changed as needed.

[0089] Multiple forced air supply devices 120 and multiple exhaust ports 130 are substantially the same as those shown in Figures 1 to 3, and multiple forced air supply devices 121 and multiple exhaust ports 131 are substantially the same as those shown in Figure 4.

[0090] Multiple exhaust ports 130, 131 may be installed on the rear surface 110R. Multiple exhaust ports 130 may be further adjacent to the top surface 110T than to the bottom surface 110B. Multiple exhaust ports 131 may be further adjacent to the bottom surface 110B than to the top surface 110T.

[0091] At least two second rollers 152 may be interposed between two adjacent first rollers 151, and at least two first rollers 151 may be interposed between two adjacent second rollers 152. Thus, in this embodiment, unlike the embodiments in Figures 2 and 4, the path line of the electrode EL may have a zigzag shape. As described above, the electrode EL may be moved by the rotation of the first rollers 151 and the second rollers 152, and the path line may be the movement path of the electrode EL.

[0092] Figure 6 is a flowchart illustrating a method for manufacturing an electrode according to an exemplary embodiment.

[0093] According to an exemplary embodiment, an electrode can be formed at P110.

[0094] A sheet-like electrode can be formed by applying an electrode slurry containing electrode active material onto a current collector, drying and rolling it to form an electrode mixture layer. The electrode slurry can be applied onto the current collector by a coating die. The coating die may be, for example, a slot die. The current collector may be a positive electrode current collector or a negative electrode current collector, and the electrode active material may be a positive electrode active material or a negative electrode active material. In addition to the electrode active material, the electrode slurry may further contain a conductive material and a binder.

[0095] The thickness of the positive electrode current collector can range from approximately 3 μm to approximately 500 μm. The positive electrode current collector may not induce chemical changes in the final manufactured secondary battery and may have high conductivity. The positive electrode current collector may include, for example, stainless steel, nickel, titanium, calcined carbon, and aluminum. The positive electrode current collector may also include stainless steel surface-treated with carbon, nickel, titanium, silver, etc. The surface of the positive electrode current collector may include a micro-textured structure to enhance the adhesion of the active material. The positive electrode current collector may be in the form of a film, sheet, foil, net, porous material, foam, nonwoven fabric, etc.

[0096] The thickness of the negative electrode current collector can range from approximately 3 μm to approximately 500 μm. The negative electrode current collector may not induce chemical changes in the final manufactured secondary battery and may have high conductivity. The negative electrode current collector may include copper, stainless steel, aluminum, nickel, titanium, calcined carbon, and aluminum-cadmium alloys. The negative electrode current collector may include stainless steel surface-treated with carbon, nickel, titanium, silver, etc. The surface of the negative electrode current collector may include a micro-textured structure to enhance the adhesion of the active material. The negative electrode current collector may be in the form of a film, sheet, foil, net, porous material, foam, nonwoven fabric, etc.

[0097] The positive electrode active material is a substance that can undergo an electrochemical reaction. The positive electrode active material can be a lithium transition metal oxide. The positive electrode active material can be, for example, a layered compound such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiO2) substituted with one or more transition metals; lithium manganese oxide substituted with one or more transition metals; chemical formula LiNi 1-y M y O2 (where M is any one of Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn, and Ga, and 0.01 ≦ y ≦ 0.7); Li 1+z Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2, Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O2, etc., such as Li 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A e (where -0.5 ≦ z ≦ 0.5, 0.1 ≦ b ≦ 0.8, 0.1 ≦ c ≦ 0.8, 0 ≦ d ≦ 0.2, 0 ≦ e ≦ 0.2, b + c + d < 1, M is any one of Al, Mg, Cr, Ti, Si, and Y, and A is any one of F, P, and Cl) represented by a lithium nickel cobalt manganese composite oxide; chemical formula Li 1+x M 1-y M’ y PO 4-z X z (where M is a transition metal, more specifically any one of Fe, Mn, Co, and Ni, M’ is any one of Al, Mg, and Ti, X is any one of F, S, and N, -0.5 ≦ x ≦ +0.5, 0 ≦ y ≦ 0.5, 0 ≦ z ≦ 0.1) may include olivine - type lithium metal phosphate represented by it.

[0098] The negative electrode active material can include carbon such as non - graphitizable carbon and graphite - based carbon. For example, the negative electrode active material can be Li xFe2O3 (0 ≦ x ≦ 1), Li x WO2 (0 ≦ x ≦ 1), Sn x Me 1-x Me’ y O z (where Me is any one of Mn, Fe, Pb, and Ge, and Me’ is any one of Al, B, P, Si, Group 1 elements, Group 2 elements, Group 3 elements, and halogens; 0 < x ≦ 1; 1 ≦ y ≦ 3; 1 ≦ z ≦ 8), etc. It may contain metal composite oxides. The negative electrode active material may include, for example, lithium metal; lithium alloys; silicon-based alloys; tin-based alloys. The negative electrode active material may include, for example, metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5. The negative electrode active material may include, for example, conductive polymers such as polyacetylene; Li-Co-Ni-based materials, etc.

[0099] The conductive material usually occupies about 1 wt% to about 30 wt% in the mixture containing the positive electrode active material. The conductive material can have conductivity without inducing chemical changes in the finally manufactured secondary battery. The conductive material may include, for example, graphite such as natural graphite and artificial graphite; carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fibers and metal fibers; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; polyphenylene derivatives, etc.

[0100] The binder can improve the bonding between the active material and the conductive material, as well as the bonding force to the current collector. The binder accounts for about 1% to about 30% by weight in the mixture containing the positive electrode active material. Examples of binders may include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluororubber, and various copolymers.

[0101] Electrode slurry can be manufactured by dissolving electrode active material, conductive material, binder, etc., in a solvent. The solvent can disperse the electrode active material, etc. The solvent may be an aqueous or non-aqueous solvent. The solvent may include dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, water, or mixtures thereof. The amount of solvent used can be adjusted to ensure that the slurry has a suitable viscosity, taking into consideration the slurry coating thickness, manufacturing yield, workability, etc.

[0102] Referring to Figures 1 and 6, the electrode EL can be dried using the electrode drying system 10. The electrode drying process is substantially the same as that described with reference to Figures 1 to 3, so redundant explanations of those will be omitted.

[0103] The present invention has been described in more detail above through the drawings and embodiments. However, the configurations described in the drawings or embodiments described herein are merely one embodiment of the present invention and do not represent the entire technical concept of the present invention. Therefore, there may be various equivalents and modifications that can be substituted for them at the time of filing.

Claims

1. An electrode drying apparatus comprising a drying chamber, a plurality of forced air supply devices installed on the upper surface of the drying chamber, and a plurality of exhaust ports installed on the rear surface of the drying chamber, configured to dry electrodes, A dehumidifier connected to the forced air supply device and configured to generate dry air supplied to the drying chamber via the forced air supply device, An electrode drying system including a manual air supply device installed in the drying chamber.

2. The electrode drying system according to claim 1, wherein the dry air generated by the dehumidifier is supplied directly to the forced air supply device.

3. The dehumidifier further includes a plurality of air supply pipes connected to it. The electrode drying system according to claim 1, wherein each of the plurality of air supply pipes is connected to a corresponding one of the plurality of forced air supply devices.

4. The system further includes multiple air supply fans installed in each of the aforementioned multiple air supply pipes, The electrode drying system according to claim 3, wherein each of the plurality of supply fans is configured to provide a driving force for transmitting the dry air through each of the plurality of supply pipes.

5. The electrode drying apparatus further includes a plurality of first rollers and a plurality of second rollers arranged within the drying chamber and configured to support the electrode, The electrode drying system according to claim 1, wherein each of the plurality of first rollers is separated from the upper surface of the drying chamber with the plurality of second rollers in between.

6. The electrode drying system according to claim 5, wherein the plurality of second rollers are interposed between the plurality of first rollers in the longitudinal direction of the electrode.

7. The electrode drying system according to claim 5, wherein the plurality of first rollers and the plurality of second rollers are configured to support the electrode such that the middle portion of the electrode is raised relative to the edge portion of the electrode.

8. The drying chamber further includes the bottom surface opposite to the top surface of the drying chamber, The electrode drying system according to claim 1, wherein the distance between each of the plurality of exhaust ports and the upper surface of the drying chamber is smaller than the distance between each of the plurality of exhaust ports and the bottom surface of the drying chamber.

9. The electrode drying system according to claim 1, wherein each of the plurality of forced air supply devices does not overlap with the electrode and the upper surface of the drying chamber in a direction perpendicular to it.

10. Each of the aforementioned multiple forced air supply devices is interposed between the electrode and the front surface of the drying chamber, The electrode drying system according to claim 1, wherein the front surface of the drying chamber is opposite to the rear surface of the drying chamber.

11. The electrode drying system according to claim 1, wherein each of the multiple forced air supply devices includes one of an anemometer, a thermometer, a hygrometer, an electric damper, and a duct.

12. The electrode drying system according to claim 1, wherein the manual air supply device is installed in front of the drying chamber.

13. The electrode drying system according to claim 12, wherein the front surface of the drying chamber is opposite to the rear surface of the drying chamber.

14. The electrode drying system according to claim 13, wherein the manual air supply device is not connected to the dehumidifier.

15. The electrode drying system according to claim 1, wherein a plurality of manual air supply devices are installed in the drying chamber.

16. The electrode drying system according to claim 15, wherein the plurality of manual air supply devices are installed in front of the drying chamber.

17. The electrode drying system according to claim 16, wherein the front surface of the drying chamber is opposite to the rear surface of the drying chamber.

18. The electrode drying system according to claim 17, wherein each of the manual air supply devices is not connected to the dehumidifier.

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