Patent Description:
This application claims the benefit of priority based on <CIT>, and <CIT>.

Lithium secondary batteries include electrodes including active materials exhibiting electrical activity, and these electrodes are manufactured by applying an active material slurry on electrode base materials to form mixture layers and drying the mixture layers. For a manufacturing process of the electrode, a slurry coating device and a drying device are generally used when manufacturing the electrode, and the drying device includes a dryer for drying a mixture layer of an electrode base material, and traveling rollers provided outside an outlet of the dryer and configured to move the dried electrode base material on which the mixture layer is dried.

Here, since the dryer removes a solvent in the slurry using high heat, the electrode base material exiting the outlet of the dryer has a thermal expansion deviation between a coated portion in which the mixture layer is formed and an uncoated portion in which the mixture layer is not formed. The thermal expansion deviation causes a problem in that the electrode base material is wrinkled or folded in a process direction in the uncoated portion while traveling.

According to the related art, in order to solve the above problem, a cooling device for cooling the electrode base material is used or a coating/drying device to which a crease roller for smoothing wrinkles or folding is applied has been developed. However, the above devices require separate spaces for introducing a cooling device or a roller, and once the above devices are installed, it is difficult to change a specification such as a width of the electrode so that there is a problem in that processability is degraded. In addition, when an uncoated portion is formed between a plurality of coated portions, there may be a limitation in that an effect of improving wrinkles or folding formed in the uncoated portion is insignificant or the coated portion is damaged.

An object of the present invention is to provide a drying device for manufacturing an electrode and a method of manufacturing an electrode using the same, which are capable of improving a thermal expansion deviation of an electrode base material which occurs between a coated portion and an uncoated portion, regardless of a shape or numbers of the coated portions to which an electrode slurry is applied and preventing wrinkles and/or a folding phenomenon, which are induced in the uncoated portion.

In one embodiment of the present invention, there is provided a drying device for manufacturing an electrode, which includes a dryer configured to dry a coated portion of an electrode base material in which the coated portion to which electrode slurry is applied is formed on at least one surface of the electrode base material and an uncoated portion to which the electrode slurry is not applied, and a transfer part coupled to an outlet of the dryer and configured to move the dried electrode base material in a process direction, wherein the transfer part includes a floating part configured to float the electrode base material using air and provided with an air floating plate, and a traveling part configured to move the floated electrode base material in the process direction.

The air floating plate includes discharge ports configured to discharge air to a surface on which the electrode base material travels, and the discharge ports are included in the entirety of a surface of the air floating plate or included only in a region in which the coated portion of the electrode base material travels.

The discharge ports of the region in which the coated portion of the electrode base material travels may have an average diameter ranging from <NUM> to <NUM>.

When the discharge ports are included in the entirety of a surface of the air floating plate, in order to control a pressure of the air discharged in each region in which the coated portion and the uncoated portion of the electrode base material travel, a diameter and/or a frequency of the discharge port may be constantly controlled.

Discharge ports in a region in which the coated portion of the electrode base material travels may have an average diameter ranging from <NUM>% to <NUM>% of that of discharge ports in a region in which the uncoated portion of the electrode base material on which the electrode slurry is not applied travels.

The number of discharge ports per unit area of a region in which the coated portion of the electrode base material travels may range from <NUM> % to <NUM>% of the number of discharge ports per unit area of a region in which the uncoated portion of the electrode base material travels.

The discharge ports are provided to form an inclined angle of <NUM>° to <NUM>° with the surface of the air floating plate in a process direction of the electrode base material.

The air floating plate may include vacuum suction holes configured to suction the discharged air at positions adjacent to the discharge ports.

The traveling part may include a tilting machine configured to tilt the air floating plates, or conveyors disposed at a front end and a rear end of the floating part and configured to slide the electrode base material in the process direction.

In another embodiment of the present invention, there is provided a method of manufacturing an electrode using the above-defined drying device, which includes drying an electrode base material in which electrode slurry is applied on at least one surface of the electrode base material at a high temperature, and floating and transferring the high-temperature dried electrode base material using air.

In the transferring of the electrode base material, the floating of the electrode base material may be performed by air discharged from the discharge ports provided in the air floating plate.

A pressure of the air discharged from the discharge ports may range from <NUM> MPa to <NUM> MPa.

When the discharge ports are included in the entirety of a surface of the air floating plate, a pressure of the air discharged in a region in which a coated portion of the electrode base material travels may range from <NUM> MPa to <NUM> MPa, and a pressure of the air discharged in a region in which an uncoated portion of the electrode base material travels may range from <NUM> MPa to <NUM> MPa.

The air used in the transferring of the electrode base material may have a temperature ranging from -<NUM> to <NUM>.

The transferring of the electrode base material may be performed at a transfer speed ranging from <NUM>/s to <NUM>/s.

A drying device for manufacturing an electrode according to the present invention includes a floating part capable of floating and moving an electrode base material to a transfer part, which transfers the dried electrode base material, using air and cooling the electrode base material, thereby preventing wrinkles and/or a folding problem induced in the uncoated portion of the electrode base material. In addition, in the floating part, since an air floating plate in which the average diameter of discharge ports and/or the number of the discharge ports per unit area are controlled according to the specifications of an electrode to be manufactured can be replaced, there is an advantage of excellent processability.

The present invention may be modified into various forms and may have a variety of embodiments, and therefore, specific embodiments will be described in detail.

However, the embodiments are not to be taken in a sense which limits the present invention to the specific embodiments and should be construed to include all modifications, equivalents, or substituents falling within the technical scope of the present invention.

In the present invention, the terms "comprising," "having," and the like are used to specify the presence of a feature, a number, a step, an operation, a component, an element, or a combination thereof described herein, and they do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, elements, or combinations thereof.

In addition, in the present invention, when a portion of a layer, a film, a region, a plate, or the like is described as being "on" another portion, this includes not only a case in which the portion is "directly on" another portion but also a case in which still another portion is present between the portion and other portion. Conversely, when a portion of a layer, a film, a region, a plate, or the like is described as being "under" another portion, this includes not only a case in which the portion is "directly under" another portion but also a case in which still another portion is present between the portion and other portion. In addition, in the present application, being disposed "on" may include the case of being disposed not only on an upper portion but also on a lower portion.

In one embodiment of the present invention, there is provided a drying device for manufacturing an electrode, which includes a dryer configured to dry a coated portion of an electrode base material in which the coated portion to which an electrode slurry is applied is formed on at least one surface of the electrode base material and an uncoated portion to which the electrode slurry is not applied, and a transfer part coupled to an outlet of the dryer and configured to move the dried electrode base material in a process direction, wherein the transfer part includes a floating part configured to float the electrode base material using air and provided with an air floating plate, and a traveling part configured to move the floated electrode base material in the process direction.

<FIG> is a perspective view illustrating the drying device for manufacturing an electrode according to the present invention. Referring to <FIG>, the drying device <NUM> for manufacturing an electrode according to the present invention includes a dryer <NUM> configured to dry an applied electrode slurry after the electrode slurry for forming an electrode mixture layer is applied to the electrode base material, and a transfer part <NUM> configured to move the electrode base material <NUM> in a process direction D when the electrode base material <NUM> on which the applied electrode slurry is dried exits the dryer <NUM>.

Here, the dryer <NUM> may include a housing and a plurality of heating elements provided in the housing. An inlet (not shown) through which the electrode base material (or an electrode current collector) <NUM>, which has passed through a coater where an electrode slurry containing one or more electrode active materials is applied on a surface of the electrode base material, is provided on one side of the housing, and an outlet <NUM> through which the electrode base material (or the electrode current collector) exits is provided on the other side of the housing. The electrode base material <NUM> passing through an inside of the housing and discharged to the outside of the housing through the outlet travels along the transfer part <NUM> coupled to a rear side of the outlet <NUM> and is wound around an electrode recovery roller.

The plurality of heating elements generate heat due to supply of electric energy and are installed inside the housing. Specifically, the plurality of heating elements are disposed above the electrode base material <NUM> in the process direction D of the electrode base material <NUM>. When the plurality of heating elements generate heat, due to the radiant heat, the electrode slurry applied to an upper surface of the electrode base material, that is, the coated portion, is dried and cured. Specifically, the dry curing of the coated portion may be performed by heating the coated portion with the radiant heat of the heating elements to remove a solvent inside the electrode slurry. To this end, in the inside of the housing, an internal temperature of a space in which the plurality of heating elements are disposed may be controlled to a temperature capable of volatilizing the solvent, and specifically, may be controlled to a temperature ranging from <NUM> to <NUM>. In addition, the heating element may be, for example, a halogen lamp. A heat reflecting plate for minimizing the loss of radiant heat implemented in the plurality of heating elements and surrounding an upper surface of each heating element to transmit the radiant heat to the electrode base material may be installed inside the housing.

In addition, the drying device <NUM> for manufacturing an electrode according to the present invention has a structure in which the transfer part <NUM> for moving the dried electrode base material <NUM> in the process direction D is continuously coupled to the outlet <NUM> of the dryer. The transfer part <NUM> includes a floating part <NUM> configured to float the electrode base material <NUM> using air and a traveling part <NUM> configured to move the floated electrode base material <NUM> in the process direction D.

Here, the floating part <NUM> includes an air floating plate <NUM> which is installed perpendicular to parallel to the process direction D of the electrode base material and in which a plurality of discharge ports for blowing air to the surface of the electrode base material <NUM> are provided in the process direction D.

The air floating plate <NUM> may discharge air to the surface of the electrode base material <NUM> through the provided discharge ports, thereby floating the dried electrode base material <NUM> and preventing wrinkles and/or a folding phenomenon from occurring in the uncoated portion in which the electrode slurry is not applied.

Specifically, when the electrode base material <NUM> to which the electrode slurry is applied is dried at a high temperature, wrinkles and/or a folding phenomenon may occur in the uncoated portion due to a thermal expansion deviation between the coated portion to which the electrode slurry is applied and the uncoated portion to which the electrode slurry is not applied. In particular, in a surface contact transfer method such as a roll-to-roll method, tension is generated in the process direction of the electrode base material <NUM>. When the tension is applied to the electrode base material <NUM> having a high temperature by drying at a high temperature, wrinkles and/or a folding may strongly occur between the coated portion and the uncoated portion of the electrode base material <NUM>. However, according to the present invention, air is discharged on the surface of the electrode base material <NUM> dried at a high temperature so that cooling of the electrode base material may be promoted. In addition, along with the cooling of the electrode base material <NUM>, the electrode base material <NUM> may be floated and moved, and thus the tension applied to the electrode base material may be minimized so that it is possible to suppress the occurrence of wrinkles and/or folding between the coated portion to which the electrode slurry is applied and the uncoated portion to which the electrode slurry is not applied.

In addition, since the air floating plate <NUM> has a plate shape, it is possible to prevent the electrode base material from shaking due to distortion between rollers or bearings according to rotation occurring in an air floating system in a form in which a plurality of rollers or a plurality of bearings are combined, and there is an advantage being able to minimize the generation of dust during the process and an advantage of safe equipment operation and easy maintenance.

In addition, a lower end of the air floating plate <NUM> is connected to an air supply part <NUM> for supplying air to a discharge port, and the air supply part <NUM> may include an air blower (not shown) for generating air. In this case, the air blower may include a motor for providing a driving force and an impeller which is rotated due to the driving of the motor, and in addition to the air blower, an air compressor and an air control unit for controlling a flow rate and a pressure of air may be further provided.

In addition, <FIG> is a schematic cross-sectional view illustrating a structure of the floating part <NUM>. Referring to <FIG>, in the floating part <NUM>, an air floating filter <NUM> is positioned between the air supply part <NUM> and the air floating plate <NUM> and may reduce a deviation of a supply amount of air discharged through a discharge port <NUM> of the air floating plate <NUM> and remove foreign materials in the air. To this end, the air floating filter <NUM> may have a mesh-sized mesh structure and include a micro channel structure in which an open pore portion guides and discharges air. In addition, in order to maintain insulation, the air floating filter <NUM> may be made of an insulating material. Specifically, the air floating filter <NUM> may employ a heat-resistant porous engineering plastic material or a porous ceramic material.

In addition, a gasket <NUM> may be further included between the air supply part <NUM> and the air floating filter <NUM> to prevent air from leaking to the outside, and in this way, it is possible to implement a pressure of the air supplied to the air floating plate <NUM> to be constantly maintained.

In addition, the air floating plate <NUM> is provided with the discharge port <NUM> for discharging air to a side surface on which the electrode base material <NUM> travels, and the discharge port <NUM> may be formed on the entire surface of the air floating plate <NUM>, that is, on the entire surface thereof or only in a region in which the coated portion of the electrode base material <NUM> travels.

Specifically, <FIG> are diagrams illustrating the surface of the air floating plate <NUM> according to the present invention. Air floating plates 214a, 214b and 214c include discharge ports 215a only in a region in which a coated portion C of the electrode base material travels as shown in <FIG> or include discharge ports 215b, 215b', 215c, and 215c' on the entire surfaces as shown in <FIG>.

As shown in <FIG>, when the discharge ports 215a are included only in the region in which the coated portion C of the electrode base material travels, the air floating plate <NUM> may minimize the loss of air discharged to the surface of the electrode base material <NUM> to increase the flotation efficiency of the electrode base material <NUM>. In addition, since the air floating plate <NUM> may induce rapid cooling of the coated portion, a temperature deviation between an electrode current collector and an active material layer (that is, the dried electrode slurry layer) which are positioned in the coated portion may be minimized to prevent the degradation of adhesive strength between the electrode current collector and the active material layer.

In addition, as shown in <FIG>, when the discharge ports 215b, 215b', 215c, and 215c' are included on the entirety of the surface of the electrode base material <NUM>, the air floating plate <NUM> may minimize a cooling rate in a direction perpendicular to a direction in which the electrode base material <NUM> travels, that is, a deviation of the cooling rate in a width direction of the electrode base material <NUM> so that bending of the electrode base material <NUM> can be prevented from occurring.

Here, in the air floating plate <NUM>, when the discharge ports 215b and 215b', 215c and 215c' are respectively included in the entirety of the surfaces of the air floating plate 214b and 214c, an average diameter of a discharge port or the number of discharge ports per unit area in the region C, in which the coated portion of the electrode base material travels, may be smaller than those of a discharge port in a region S in which the uncoated portion of the electrode base material to which the electrode slurry is not applied travels.

As one example, when the air floating plates 214b and 214c respectively include the discharge ports 215b and 215b', 215c and 215c' on the entirety of the surfaces, the discharge port of the region C in which the coated portion of the electrode base material travels may have an average diameter ranging from <NUM>% to <NUM>% of that of the discharge port in the region S in which the uncoated portion of the electrode base material to which the electrode slurry is not applied travels. Specifically, each discharge port of the air floating plates 214b and 214c may have an average diameter ranging from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, or from <NUM>% to <NUM>% of that of each discharge port of the region S in which the uncoated portion of the electrode base material travels.

Here, the discharge port of the region C in which the coated portion of the electrode base material travels is not particularly limited as long as it has an average diameter suitable for discharging air sufficient to float the electrode base material including the coated portion. Specifically, the discharge port may have an average diameter ranging from <NUM> to <NUM>, and more specifically, may have an average diameter ranging from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, or from <NUM> to <NUM>.

As another example, when the air floating plates 214b and 214c respectively include the discharge ports 215b and 215b', 215c and 215c' on the entirety of the surfaces, the number of discharge ports per unit area of the region C in which the coated portion of the electrode base material travels may range from <NUM>% to <NUM>% of the number of discharge ports per unit area of the region S in which the uncoated portion of the electrode base material travels, and specifically, may range from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, or from <NUM>% to <NUM>% of the number of discharge ports per unit area of the region S in which the uncoated portion of the electrode base material travels.

According to the present invention, the average diameter and the number per unit area according to the positions of the discharge ports 215b and 215b', 215c and 215c' respectively introduced into the air floating plates 214b and 214c are controlled in the above ranges, and thus the electrode base material <NUM> on which the electrode slurry is applied may be stably floated and the uncoated portion in which the electrode slurry is not applied may be heated to a high temperature and then rapidly cooled to a temperature lower than room temperature to rapidly cure a base material of the uncoated portion. In this way, it is possible to improve a thermal expansion deviation of the electrode base material <NUM>.

In addition, the discharge ports 215a, 215b and 215b', 215c and 215c' respectively introduced into the surface of the air floating plate 214a, 214b, and 214c may each have a porosity (aperture ratio) ranging from <NUM>% to <NUM>%, and specifically, from <NUM>% to <NUM>%. According to the present invention, the porosity (aperture ratio) of each discharge port introduced into the air floating plates 214a, 214b and 214c is controlled within the above range so that a flow of air discharged to the surfaces of the air floating plates 214a, 214b, and 214c may be smooth and an inflow of fine particles present in the air may be blocked.

In addition, the discharge ports 215a, 215b, 215b', 215c, and 215c' of the air floating plate applied to the present invention may be formed perpendicular to the direction D in which the electrode base material <NUM> travels, or as shown in <FIG>, or may be provided to form an inclined angle α ranging from <NUM>° to <NUM>° with the surfaces of the air floating plates 214a, 214b, and 214c in the process direction D in which the electrode base material <NUM> travels. Specifically, the discharge ports 215a, 215b, 215b', 215c, and 215c' may be formed perpendicular to the direction D in which the electrode base material <NUM> travels or may be provided to form an inclined angle α, with the surfaces of the air floating plates 214a, 214b, and 214c, ranging from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, or from <NUM>° to <NUM>°.

According to the present invention, by controlling the angles of the discharge ports 215a, 215b, 215b', 215c, and 215c' to satisfy the above range, the electrode base material may be moved with little energy due to the discharged air.

In addition, the air floating plates 214a, 214b, and 214c respectively include the discharge ports 215a, 215b and 215b', 215c and 215c' for discharging the air to the surface on which the electrode base material travels and may include vacuum suction holes <NUM> for suctioning the air, which is discharged through the discharge ports 215a, 215b, 215b', 215c, and 215c', again at positions adjacent to the discharge ports 215a, 215b, 215b', 215c, and 215c'.

The air floating plates 214a, 214b and 214c are not particularly limited as long as they are positioned adjacent to the discharge ports provided on the surfaces and may include the vacuum suction holes <NUM> for suctioning the discharged air again. Specifically, as shown in <FIG>, the vacuum suction holes <NUM> may be provided between the region C in which the coated portion of the electrode base material <NUM> travels and the region S in which the uncoated portion of the electrode base material travels or a column of discharge ports and a column of vacuum suction holes <NUM> may be alternately provided in the direction D in which the electrode base material <NUM> travels.

The vacuum suction holes <NUM> are for stably transporting the dried electrode base material <NUM> and may be disposed at positions adjacent to the discharge ports 215a, 215b, 215b', 215c, and 215c' to facilitate air exhaust. In this way, a bending phenomenon of the electrode base material <NUM> may be minimized and it is possible to easily control fluctuations, floating flatness, and a height.

In addition, in the floating part <NUM>, since the air floating plates 214a, 214b, and 214c may be separated and replaced, an air floating plate in which an average diameter and the number of discharge ports are controlled according to the specifications of the electrode to be manufactured may be applied.

In this case, as shown in <FIG>, the air floating plates 214a, 214b, and 214c may each have a structure in which discharge ports having an average diameter, the number per unit area, and/or porosity controlled according to the coated portion and the uncoated portion of the electrode base material <NUM> are provided on one plate-shaped base material.

Alternatively, as shown in <FIG> and <FIG>, the air floating plates 214a, 214b, and 214c may each have a structure in which a plurality of rod-shaped base materials may be assembled according to positions of the coated portion and the uncoated portion of the electrode base material <NUM>. In this case, processability and assemblability of the air floating plate are high so that there is an advantage in that the degree of freedom and responsiveness in terms of a design of the electrode base material is improved.

Meanwhile, the transfer part <NUM> includes a traveling part <NUM> as a part for moving the electrode base material <NUM> floated by the floating part <NUM>. The traveling part <NUM> is not particularly limited as long as it can move the floated electrode base material <NUM>, and specifically, may include a tilting machine for tilting and erecting the air floating plates 214a, 214b, 214c and a conveyor disposed at a front end and a rear end of the floating part <NUM> and configured to slide the electrode base material <NUM> in the process direction D.

Here, the tilting machine is a device for tilting the air floating plates 214a, 214b and 214c to be inclined so that the floated electrode base material <NUM> is moved in an inclined direction. A tilting frame is positioned on one side opposite to the surface on which the electrode base material <NUM> of each of the air floating plates 214a, 214b, and 214c travels so that the air floating plates 214a, 214b and 214c may be erected to be inclined.

The tilting machine is a device for applying an external force so that the electrode base material <NUM> floated by each of the air floating plates 214a, 214b, 214c is moved at an appropriate speed due to gravity and an inclined angle, and the inclined angle implemented by the tilting machine may range from <NUM>° to <NUM>°, and more specifically, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, from <NUM>° to <NUM>°, or from <NUM>° to <NUM>°.

In addition, the conveyor may be disposed at each of the front end and the rear end of the floating part <NUM> to move the electrode base material <NUM>. In this case, the conveyor may include one or more of a belt type conveyor and/or a roller type conveyor.

Specifically, <FIG> is a perspective view illustrating a case in which the transfer part <NUM> is provided with a conveyor as the traveling part <NUM>. Referring to <FIG>, the conveyor may include a first conveyor <NUM> positioned at the front end of the floating part <NUM> and a second conveyor <NUM> positioned at the rear end of the floating part. The first conveyor <NUM> and the second conveyor <NUM> may be formed to be coplanar with the air floating plate <NUM> of the floating part <NUM> to prevent jamming from occurring while the electrode base material <NUM> is moved.

In some cases, the transfer part <NUM> may further include an unwinder (not shown) for supplying the electrode base material <NUM> to the dryer <NUM> and a winder (not shown) for winding the electrode base material having passed through the dryer. The unwinder may supply the electrode base material <NUM> to the dryer, thereby applying a pushing force to the electrode base material <NUM> and moving the electrode base material <NUM> in the process direction D, and the winder may apply a pulling force to the dried electrode base material <NUM> in the process direction D, thereby moving the dried electrode base material <NUM>. To this end, the unwinder may be located at a front end of the dryer <NUM>, and the winder may be located at a rear end of the floating part <NUM>.

Since the drying device <NUM> for manufacturing an electrode according to the present invention includes the above-described components, it is possible to improve the thermal expansion deviation of the electrode base material <NUM> dried at high temperature so that wrinkles and/or a folding problem induced in the uncoated portion of the electrode base material may be prevented. In addition, in the floating part <NUM>, the air floating plate <NUM> in which the average diameter of the discharge ports <NUM> and/or the number of discharge ports <NUM> per unit area are controlled according to the specifications of the electrode to be manufactured may be replaced so that there is an advantage of excellent processability.

In one embodiment of the present invention, there is provided a method of manufacturing an electrode, which includes drying an electrode base material in which an electrode slurry is applied on at least one surface of the electrode base material at a high temperature, and floating and transferring the high-temperature dried electrode base material using air.

The method of manufacturing an electrode according to the present invention may include applying the electrode slurry on at least one surface of the electrode base material to form an electrode mixture layer, and drying the electrode base material, on which the electrode slurry is applied, at high temperature, and floating and transferring the dried electrode base material using air and may be performed using the above-described drying device for manufacturing an electrode of the present invention.

Specifically, in the drying of the electrode base material, when the electrode base material (or electrode current collector) which has passed through the coater and on which the electrode slurry containing one or more electrode active materials is applied to the surface is introduced into the dryer of the drying device, a solvent in the electrode slurry applied to the electrode base material may be removed by a plurality of heating elements provided in the dryer and thus the applied electrode slurry may be cured to form an electrode mixture layer. In this case, a temperature in the dryer due to radiant heat of the heating elements may be specifically controlled in the range of <NUM> to <NUM>.

In addition, the transferring of the dried electrode base material may be performed by the transfer parts continuously coupled to the outlet of the dryer. Specifically, when the dried electrode base material exits through the outlet of the dryer, the dried electrode base material enters the transfer part coupled to the outlet. The entering electrode base material is floated by the air floating plate of the transfer part and is moved in the process direction in a state of being floated. Here, the air floating plate includes the discharge ports for discharging air to the surface of the electrode base material in a direction in which the electrode base material travels, and the air discharged through the discharge ports may float the dried electrode base material and may satisfy a predetermined range of a pressure and/or a temperature so as to improve wrinkles and/or a folding phenomenon occurring in the uncoated portion of the electrode base material due to the electrode slurry heated to a high temperature.

Specifically, the pressure of the air discharged through the discharge ports may be controlled in the range of <NUM> MPa to <NUM> MPa, and more specifically, in the range of <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, <NUM> MPa to <NUM> MPa, or <NUM> MPa to <NUM> MPa.

As one example, when the discharge ports are included in the entirety of the surface of the air floating plate, the pressure of the air discharged from the region in which the coated portion of the electrode base material travels may range from <NUM> MPa to <NUM> MPa or from <NUM> MPa to <NUM> MPa, and the pressure of the air discharged from the region in which the uncoated portion of the electrode base material travels may range from <NUM> MPa to <NUM> MPa or <NUM> MPa to <NUM> MPa.

In addition, the temperature of the air discharged through the discharge ports may be controlled in the range of -<NUM> to <NUM>, and specifically, in the range of -<NUM> to <NUM>, -<NUM> to <NUM>, -<NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM>.

As one example, when the discharge ports are included in the entirety of the surface of the air floating plate, the temperature of the air discharged from the region in which the coated portion of the electrode base material travels may range from <NUM> to <NUM>, and the temperature of the air discharged from the region in which the uncoated portion of the electrode base material travels may range from -<NUM> to <NUM>.

According to the present invention, by controlling the pressure and the temperature of the air discharged from the discharge ports of the air floating plate in the above-described ranges, the dried electrode base material may be stably floated, and the uncoated portion of the electrode base material, in which the high-temperature electrode slurry is not applied, is rapidly cured so that thermal expansion deviation between the coated portion and the uncoated portion may be reduced.

In addition, in the transferring of the dried electrode base material, a transfer speed of the electrode base material may be appropriately controlled to stably move the electrode base material in the state of being floated. To this end, the transfer speed of the electrode base material may be controlled in the range of <NUM>/s to <NUM>/s, and specifically in the range of <NUM>/s to <NUM>/s, or <NUM>/s to <NUM>/s.

Since the method of manufacturing an electrode according to the present invention includes the above-described components, it is possible to improve the thermal expansion deviation of the electrode base material dried at a high temperature so that wrinkles and/or a folding problem induced in the uncoated portion of the electrode base material may be prevented.

Hereinafter, the present invention will be described in more detail with reference to examples and experimental examples.

However, the following examples and experimental examples are merely illustrative of the present invention, and the content of the present invention is not limited to the following examples and experimental examples.

In order to evaluate the performance of the drying device for manufacturing an electrode according to the present invention, the following experiment was performed.

Specifically, a steel plate having a length of <NUM> × a width of <NUM> × a thickness of <NUM> was prepared, and discharge ports having an average diameter and the number per unit area as shown in Table <NUM> were formed on a surface of the steel plate to manufacture an air floating plate.

Then, separately, a first conveyor in the form of a roller, a floating part, and a second conveyor in the form of a roller were coupled to the outlet of the dryer having an internal temperature of about <NUM> by a halogen lamp, and the air floating plate produced in advance was mounted on a front portion of the floating part to prepare the drying device for manufacturing an electrode. In this case, as shown in <FIG>, the floating part has a structure in which the gasket <NUM>, the air floating filter <NUM>, and the air floating plate <NUM> are sequentially stacked on the lower table <NUM> provided with an air supply hole 211a, and an air supply part <NUM> is coupled to the air supply hole 211a of the lower table <NUM> so that the floating part has a structure in which air is supplied to the air floating plate <NUM>.

The electrode base material on which the electrode slurry was applied was dried and transferred (a transfer speed of about <NUM>/s) using the prepared drying device for manufacturing an electrode. In this case, the temperature of the air discharged from the air floating plate was controlled to a temperature of <NUM> in the region in which the coated portion of the electrode base material traveled and was controlled to a temperature of <NUM> in the region in which the uncoated portion of the electrode base material traveled. In addition, a degree of floating of each electrode and whether wrinkles and/or folding occurred in the uncoated portion of the electrode base material were checked. The evaluation criteria are as follows, and the results are shown in Table <NUM> below.

As shown in Table <NUM> above, the drying device for manufacturing an electrode according to the present invention may float the electrode base material dried at a high temperature to safely move the electrode base material using air and reduce the thermal expansion deviation between the coated portion and the uncoated portion of the electrode base material due to the high temperature drying so that it can be seen that an effect of improving wrinkles and/or a folding phenomenon of the uncoated portion is excellent.

From the above results, the drying device for manufacturing an electrode according to the present invention can dry the electrode base material on which the electrode slurry is applied at a high temperature and then float and move the electrode base material and can prevent wrinkles and/or a folding phenomenon due to the thermal expansion deviation between the coated portion and the uncoated portion of the electrode base material without damage to the coated portion so that it can be seen that processability is excellent.

Although the above description has been made with reference to exemplary embodiments of the present invention, it should be understood that various alterations and modifications of the present invention can be devised by those skilled in the art to which the present invention pertains without departing from the scope of the present invention, which is defined by the appended claims.

Claim 1:
A drying device (<NUM>) for manufacturing an electrode, comprising:
a dryer (<NUM>) configured to dry a coated portion of an electrode base material (<NUM>) in which the coated portion to which an electrode slurry is applied is formed on at least one surface of the electrode base material (<NUM>) and an uncoated portion to which the electrode slurry is not applied; and
a transfer part (<NUM>) coupled to an outlet (<NUM>) of the dryer (<NUM>) and configured to move the dried electrode base material (<NUM>) in a process direction (D),
wherein the transfer part (<NUM>) includes:
a floating part (<NUM>) configured to float the electrode base material (<NUM>) using air and provided with an air floating plate (<NUM>); and
a traveling part (<NUM>) configured to move the floated electrode base material (<NUM>) in the process direction (D),
wherein:
the air floating plate (<NUM>) includes discharge ports (<NUM>) configured to discharge air to a surface on which the electrode base material (<NUM>) travels; and
the discharge ports (<NUM>) are included in the entirety of a surface of the air floating plate (<NUM>) or included only in a region (C) in which the coated portion of the electrode base material (<NUM>) travels,
characterized in that the discharge ports (<NUM>) are provided to form an inclined angle (α) of <NUM>° to <NUM>° with the surface of the air floating plate (<NUM>) in the process direction (D) of the electrode base material (<NUM>).