KR20140032897A - Method and device for manufacturing electrode for secondary battery - Google Patents

Abstract

The present invention relates to an apparatus and manufacturing method for a secondary battery. More specifically, a manufacturing method and apparatus for an electrode plate of the secondary battery, in which an active material is firmly bond to a metal sheet and at the same time, the manufacturing cost is reduced. The manufacturing method of the secondary battery according to the present invention includes a step of applying an active material layer on a surface of the metal sheet and a step of drying the active material layer. The drying step is characterized in that direct heating on the metal sheet to dry the side of the active material layer in contact with metal sheet results in escaping bubbles from the outer surface of the active material layer. According to the present invention, direct heating on the metal sheet of the electrode for the secondary battery results in drying the inside surface of the active material layer in contact with the metal sheet in advance, thereby drying the outer surface of the active material layer Accordingly, uniform bubbles have formed on the active material layer and the contact area between the active material layer and the metal sheet has increased to have strong binding force. Therefore, the amount of a bonding agent for manufacturing electrode has reduced to have superior conductivity of the electrode for the secondary battery.

Description

Electrode manufacturing method and apparatus for secondary batteries {METHOD AND DEVICE FOR MANUFACTURING ELECTRODE FOR SECONDARY BATTERY}

The present invention relates to a method and apparatus for producing an electrode for secondary batteries. More specifically, the present invention relates to a method and apparatus for manufacturing an electrode for secondary batteries, which can firmly bond an active material layer to a thin metal plate and at the same time reduce manufacturing costs.

Secondary batteries are used in portable electronic devices such as mobile phones, digital cameras, notebook computers, and various devices such as hybrid vehicles and electric vehicles. Secondary batteries include lead acid batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lithium ion batteries, lithium polymer batteries, and lithium metal batteries. The secondary battery basically has four elements: a positive electrode, a negative electrode, a separator, and an electrolyte.

The positive electrode and the negative electrode are electrodes in which energy conversion and storage such as oxidation / reduction occur, and have positive and negative potentials, respectively. The separator is located between the anode and the cathode to maintain electrical isolation and to provide a path for charge transfer. The electrolyte serves as a medium for charge transfer.

Each electrode is coated with an active material on a thin metal plate. As the metal thin plate, aluminum or copper thin plate is often used.

The active materials applied to the positive electrode include lithium cobalt oxide (LixCoO2), lithium nickel oxide (LixNiO2), lithium nickel cobalt oxide (Lix (NiCo) O2), lithium nickel cobalt manganese oxide (Lix (NiCoMn) O2), spinel type lithium Oxides such as manganese oxide (LixMn2O4), manganese dioxide (MnO2), or olivine type such as lithium iron phosphate (LixFePO4), lithium manganese phosphate (LixMnPO4), NASICON type phosphates, silicates (silicates), sulfates sulfates, or polymeric materials.

As the active material applied to the negative electrode, a polymer material or a carbon material may be used, and graphite-based, non-graphitizable carbon, or hard-carbon, such as artificial or natural graphite, or graphitizable carbon may be used. (graphitizable carbon, soft-carbon), carbon nanotube (CNT), carbon nanofiber (carbon nanofiber, CNF), carbon nanowall (carbon nanowall, CNW) and the like can be used.

The separator is generally a porous polymer membrane such as polyolefin-based, polyester-based, and natural polymers such as pulp, cellulose, and cork, such as polyethylene and polypropylene. Alternatively, a nonwoven form may be used, and a structure of a single layer film or a multi layer film may be used. In addition, a thermoplastic polyolefin polymer porous multilayer film (Tm 100 to 150 ° C.) such as polyethylene or polypropylene, or a high molecular weight to ultra high molecular weight thermoplastic heat resistant polyolefin polymer porous film (Tm 150 to 200 ° C.) may be used. The electrolyte uses a liquid electrolyte composed of an organic solvent and a salt, and provides a flow path of ions moving between the positive electrode and the negative electrode during the charging and discharging of the battery.

 BACKGROUND OF THE INVENTION Conventionally known electrode manufacturing processes generally include a coating step of applying an active material layer in the form of a slurry to the surface of a thin metal plate, and a drying step of drying the active material layer coated with the active material.

The active material in the form of a slurry is composed of an electrode component and a dispersion medium, and the electrode component is composed of the active material, the conductive material, the binder, and other additives. Among them, a binder is a material for improving binding force between electrode constituent materials such as an electrode active material, a conductive material, and adhesion between the electrode constituent material and a metal thin plate, and a polymer may be used, and vinylidene fluoride may be used. Series, vinylchloride series, vinylalcohol series, acrylate series, ether series, acrylonitrile series, imide series, rubber series, A siloxane-based, silicon polymer, or the like can be used. Dispersing medium is a material capable of dissolving or dispersing the binder, pyrolidinone series, furan series, amide series, nitrile series, ketone series, alcohol Series, water and the like can be used.

The binder included in the active material is preferred because it may interfere with the material or electrical conduction necessary for the stability of the electrode, that is, binding and adhesion. However, if the content of the binder is reduced, the binding force between the electrode components and the adhesion between the electrode components and the metal sheet may be lowered, so that the adjustment is made at an appropriate level.

In a conventional drying process, a method of applying hot air to a metal thin plate coated with an active material or heating an atmosphere with a resistance heating element is mainly used. The conventional drying method forms a drying chamber in the form of a tunnel, and continuously passes through the inside of the chamber a metal thin plate coated with an active material while maintaining the temperature inside the chamber at a predetermined temperature.

In the drying method as described above, drying occurs from the outside of the active material layer in contact with the air of high temperature, and drying proceeds to the inside of the metal thin plate. At this time, the drying occurs first and the gas generated in the interior where the drying proceeds passes through the outer wall of the active material layer in which the solidification proceeds and is discharged to the outside. Therefore, agglomeration and uneven pores of the active material particles are locally formed in the active material layer in which the solidification proceeds. Aggregation or uneven pores of the active material particles cause a decrease in the binding force between the constituent materials and the adhesion between the electrode constituent material and the metal thin plate.

Meanwhile, Japanese Patent Laid-Open No. 2004-327203 published on Nov. 18, 2004, entitled `` Method for Producing Electrode, '' discloses a technique for drying an active material of an electrode of a secondary battery by an induction heating method. It is open. The technique disclosed in this patent shields the portion where the active material is not coated, in order to solve the problem that the temperature of the portion where the active material is not coated is excessively higher than the portion where the active material of the metal foil is applied, thereby deforming or breaking the metal sheet. A method of shielding with a plate and heating only the active material application portion is provided.

However, when only the portion coated with the active material is heated by the method disclosed in the patent, the thermal expansion of the metal sheet unevenly occurs in the width direction due to the temperature difference between the portion coated with the active material and the portion not coated with the active material. do. Therefore, when the metal sheet is transported by pulling at a constant tension, wrinkles or sagging portions are generated, resulting in uneven thickness of the active material.

It is an object of the present invention to provide a new drying step that can provide an active material layer having excellent binding strength between components and adhesion to a metal thin plate in a method for producing an electrode for secondary batteries. Moreover, an object of this invention is to provide the manufacturing apparatus of the secondary battery electrode provided with the drying apparatus which can dry the active material layer excellent in the binding force between component materials, and the adhesive force with a metal thin plate in the manufacturing apparatus of a secondary battery electrode. .

In addition, an object of the present invention is to provide a method and apparatus for manufacturing a secondary battery electrode for preventing the damage caused by thermal deformation of the thin plate by uniformly heating the metal plate coated with the active material.

Disclosed is a method for manufacturing a secondary battery electrode according to one aspect of the present invention. The method of manufacturing an electrode for a secondary battery according to the present invention includes an active material coating step of applying an active material layer to one surface of a metal thin plate, and a drying step of drying the active material layer. The drying step is characterized in that the metal sheet is directly heated so that the active material layer is dried from the side in contact with the metal sheet to the top of the active material layer so that bubbles are released to the outer surface of the active material layer.

When the active material layer is dried from the inside in contact with the heated metal thin plate, the generated bubbles are easily discharged to the upper part of the slurry state that is not dried to form uniform pores therein, thereby preventing local active particles from agglomerating locally. can do. In addition, when the active material layer is dried from the outside to the inside by using hot air as in the prior art, the inside of the active material layer, which is dried outside and dried, shrinks due to drying to form non-uniform pores, and adheres to the metal thin plate. The area is also reduced. On the other hand, if the metal thin plate is directly heated to dry the inside of the active material layer in contact with the metal thin plate first, and the drying proceeds to the outside of the active material layer, bubbles are easily discharged and the adhesion area with the metal thin plate is increased, thereby increasing the adhesive strength. do. Therefore, since a binder may be used little in manufacture of an electrode, the electrode for secondary batteries which is excellent in electrical conductivity can be manufactured.

In addition, the drying step includes the step of transferring the metal thin plate in the longitudinal direction, the arrangement so that the sum of the magnetic flux density that chains the metal thin plate with respect to the longitudinal transfer length of the metal thin plate uniformly distributed along the width direction. It is preferable to dry the active material by induction heating of the thin metal plate with the inductive coupling coil. Further, the thin metal sheet may be heated and dried by an inductive coupling coil arranged such that the sum of the current densities induced by the magnetic flux that bridges the thin metal sheet with respect to the conveying length of the thin metal sheet is uniformly distributed along the width direction. When the metal thin plate is heated with the inductive coupling coil arranged as described above, the metal thin plate may be uniformly heated in the width direction to prevent non-uniform thermal expansion of the metal thin plate, thereby preventing damage due to thermal expansion.

As the metal thin plate, a thin plate made of aluminum or copper is used. It is preferable to use induction heating for the method of directly heating the metal thin plate, but is not limited thereto. Infrared lamps or roller-type electric heaters may be heated by direct contact with a thin metal sheet. In particular, in the manufacturing process of the electrode for secondary batteries, a roll-to-roll process having excellent productivity is frequently used. The metal sheet is continuously supplied from the unwinder, and the active material in slurry form is applied to the surface, and the continuously dried and dried electrode is wound in the unwinder. When drying by induction heating in a roll-to-roll production process, the drying step includes transferring the thin metal sheet in the longitudinal direction, and inducing the upper and lower portions of the thin metal sheet to cross the width direction of the thin metal sheet. Applying an alternating voltage to the coupling coil. A high frequency voltage is required to heat the continuously thin metal sheet in a short time. The alternating voltage applied to the inductive coupling coils for heating the thin metal sheet preferably has a frequency in the range of approximately 100 KHz to 500 kHz.

According to another aspect of the present invention, an electrode manufacturing apparatus of a secondary battery is disclosed. An electrode manufacturing apparatus for a secondary battery according to the present invention includes a unwinding part for continuously supplying a metal thin plate wound in a roll shape, an active material applying part for applying an active material layer to one surface of the uncovered metal thin plate, and the metal thin plate. And a drying unit for drying the active material layer applied to the roll, and a winding unit for winding the thin metal plate on which the active material layer is dried in a roll form. The drying unit includes an inductive coupling coil for directly heating the metal sheet on which the active material layer is applied. The inductive coupling coil is provided to traverse in the width direction of the metal sheet at a distance from one surface of the metal sheet. An inductive coupling coil is installed on top of the metal sheet to generate an induction current in the metal sheet to directly heat the metal sheet. The inductive coupling coil may be installed such that a pair of copper bars are spaced apart by a predetermined distance and returned across the width direction of the metal sheet. The drying unit includes a power source for applying an alternating voltage to the inductive coupling coil. The AC voltage applied from the power source to the inductive coupling coil preferably has a frequency in the range of 100 KHz to 500 kHz.

In addition, the induction coupling coil may further include a core installed at both sides of the width direction of the metal sheet of the induction coupling coil in order to prevent the widthwise edge of the metal sheet from being heated to a locally high temperature. In addition, in order to prevent the induction coupling coil from being heated at a locally high temperature in the widthwise edge of the thin metal sheet, it is preferable to use one bent so that the vicinity of both ends in the width direction of the thin metal sheet is separated from the thin metal sheet.

In addition, in some embodiments, the secondary electrode manufacturing apparatus may include a plurality of inductive coupling coils. The plurality of inductive coupling coils may be bent in a U shape, and neighboring inductive coupling coils may be alternately installed such that the bent ends of the U-shaped coils are located in opposite directions.

Further, in some embodiments, the plasma processing unit may further include a plasma processing unit for surface treatment by spraying a gas in a plasma state on at least one surface of the metal thin plate between the unwinding unit and the active material applying unit. The plasma processing unit cleans the surface by spraying plasma gas on the surface of the metal thin plate, and modifies the properties of the surface to be hydrophilic, so that the active material adheres well.

According to this invention, the manufacturing method and manufacturing apparatus of an electrode for secondary batteries are provided. According to the present invention, the metal thin plate of the secondary battery electrode is directly heated so that the inside in which the active material layer applied to the metal thin plate contacts the metal thin plate is first dried, so that drying proceeds to the outside of the active material layer. Therefore, uniform bubbles are formed in the active material layer, and the adhesion area between the active material layer and the metal thin plate is increased, so that the bonding force is excellent. Therefore, since a binder may be used little in manufacture of an electrode, the electrode for secondary batteries which is excellent in electrical conductivity can be manufactured. In addition, the drying method according to the present invention, by heating the metal sheet to a uniform temperature to prevent damage to the metal sheet due to thermal deformation.

In addition, the drying apparatus according to the present invention directly heats the metal sheet using induction heating, and thus does not require a separate long length drying chamber for hot air heating, thereby reducing the size of the apparatus. In addition, since the metal sheet is directly heated, there is no energy discharged to the outside by hot air, thereby reducing energy costs for drying. In addition, the thin metal sheet can be heated to a high temperature in a short time, so that the drying time is shortened and the productivity is improved. In addition, the drying apparatus according to the present invention, by heating the metal sheet to a uniform temperature to prevent damage to the metal sheet due to thermal deformation.

1 is a schematic diagram illustrating a state in which an active material layer is dried in a method and apparatus for manufacturing an electrode according to the present invention;
2 is a schematic view of an apparatus for manufacturing a secondary battery electrode according to the present invention.
3 is a schematic view showing one embodiment of an inductive coupling coil installed on top of a thin plate electrode
4 is a schematic view showing another embodiment of an inductive coupling coil installed on an upper portion of a thin plate electrode;
5 is a schematic explanatory diagram showing an arrangement state of the inductive coupling coil of the embodiment shown in FIG.
FIG. 6 is an explanatory view showing a temperature distribution of a metal sheet heated by an inductive coupling coil of the embodiment shown in FIG.
7 is an explanatory diagram showing a temperature distribution of a metal sheet heated by an inductive coupling coil of the embodiment shown in FIG.
8 is a schematic view of another embodiment of the apparatus for manufacturing a secondary battery electrode according to the present invention;
9 is a top schematic view of the drying section of the apparatus of FIG.
FIG. 10 is an explanatory view showing a widthwise temperature distribution of a cross section of AA to EE of a metal sheet heated by an inductive coupling coil in which both ends are not bent in FIG. 9; FIG.
FIG. 11 is an explanatory view showing a widthwise temperature distribution of a cross section of AA to EE of a metal sheet heated by an inductive coupling coil bent at both ends in FIG. 9; FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, in order to manufacture an electrode for a secondary battery according to the present invention, an active material layer 165 is first applied to one surface of a metal thin plate 160 (FIG. 1A). The metal thin plate 160 uses copper or aluminum. The active material is used for the positive electrode and the negative electrode. The manufacturing method of the present invention is applied to both the production of the anode electrode and the cathode electrode. As the coating method of the active material, a slit-die method, a gravure method, a doctor blade method, a silk screen method, an offset method, a spray method, A dip scheme or the like can be used. As shown in FIG. 2, the metal roller 60 may be applied to the active material supply nozzle 120 while supporting the thin metal plate 60 with the backup roller 110.

Next, energy is supplied to the metal thin plate 160 to directly heat the metal thin plate (FIG. 1B). Induction heating is preferable as a method of directly heating the metal thin plate 160, but is not limited thereto. The metal thin plate 160 may be directly heated using an infrared lamp. In the case of induction heating, an inductive coupling coil may be installed on the upper or lower portion of the active material layer to heat it, and when heated using an infrared lamp, the metal sheet may be heated to heat the lower surface of the metal sheet on which the active material is not coated. It is preferable to install in the lower part.

Next, when the thin metal plate is heated, as drying proceeds from the inside 165a of the active material layer in contact with the thin metal plate, bubbles generated in the inside 165a pass through the outer layer 165b in a slurry state that has not yet been dried. Is released into the atmosphere (FIG. 1C). As drying proceeds from the inside of the slurry active material layer 165 to the outside (FIG. 1D), bubbles are formed uniformly inside the active material layer, and the adhesion area between the metal thin plate 160 and the active material layer 165 is Increases the adhesion. This is because the manufacturing method according to the present invention prevents agglomeration of the non-uniform voids and the active material from shrinkage that occurs when the active material is dried and solidified when the outside of the active material is dried and the inside is dried later. In addition, the binding force between the constituent materials of the active material layer 165 is increased due to uniform bubbles in the active material layer 160. Therefore, since a binder may be used little in manufacture of an electrode, the electrode for secondary batteries which is excellent in electrical conductivity can be manufactured.

Referring to FIG. 2, an apparatus for manufacturing a secondary battery electrode includes an unwinding part 100 for continuously supplying a metal thin plate 160 wound in a roll shape, and an active material layer on one surface of the unwinded metal thin plate 160. An active material application part 120 for applying the coating material 165, a drying part 130 for drying the active material layer applied to the metal thin plate, and a winding part 140 for winding the metal thin plate on which the active material layer is dried in a roll form. Include. The active material applying unit 120 has slits formed in the width direction of the metal thin plate 160, and the active material having a predetermined thickness is coated on one surface of the metal thin plate using the slits. The backup roller 110 supports the metal thin plate 160 to stably apply the active material. The rollers 151-156 are idle rollers for guiding the transfer of the thin metal plate 160.

The metal thin plate 160 on which the active material layer 165 is formed is continuously supplied to the drying unit 130. In the drying unit 130, the inductive coupling coil 131 is installed at regular intervals on the upper portion of the metal thin plate 160. The inductive coupling coil 131 includes a pair of conductor (copper) bars 131 provided at regular intervals on top of the metal sheet. Although not shown, a magnetic core may be additionally installed in the induction coupling coil 131 to focus the magnetic flux generated by the induction coupling coil 131. In addition, magnetic cores 132a-d are provided at both ends of each conductor bar of the inductive coupling coil 131. The magnetic cores 132a-d adjust the path of the magnetic field induced in the induction heating coil to adjust the excessive heating of the edge in the width direction of the thin metal plate.

Referring to FIG. 3, an AC power source 135 is connected to the inductive coupling coil 131. The AC power source 135 applies a high frequency voltage, a high frequency voltage in the range of approximately 300 kHz to 500 kHz, to the induction heating coil 131. When an alternating voltage is applied to the induction heating coil 131, electromotive force is induced in the thin plate by an electromagnetic induction phenomenon, and the metal thin plate 160 is heated by an induction current generated by the electromotive force.

4 and 5, the inductive coupling coil 131 of the present embodiment is bent such that both edges in the width direction of the metal thin plate 160 are separated from the metal thin plate 160. This is for controlling that the width | variety of the width direction edge of the metal thin plate 160 rises rapidly by induction heating. In order to heat the metal sheet to have a uniform temperature distribution in the width direction, the length of the unbent flat portion w2 of the inductive coupling coil 131 with respect to the width w1 of the metal sheet 160, and the metal sheet ( The interval t between the induction coupling coil 131 and the bending angles θ1 and θ2 at the edges of the metal thin plate 160 may be determined by the material, the feed rate and the thickness of the metal thin plate 160, It is a value determined according to the coating thickness of the component and the active material layer, the shape and arrangement of the inductive coupling coil 131, and the like.

FIG. 6 shows the temperature distribution in the width direction of the thin metal plate 160 heated by the inductive coupling coil 131 that is not bent at both ends of the embodiment shown in FIG. 3. It can be seen that both ends of the metal thin plate 160 in the width direction are excessively heated.

FIG. 7 illustrates a temperature distribution in the width direction of the metal thin plate 160 heated by the inductive coupling coil 131 bent at both ends of the embodiment illustrated in FIG. 4. It can be seen that the temperature of both ends of the inductive coupling coil 131 is bent to be lower than the temperature of the flat portion w2. The width of the flat portion w2, the bending angles θ1, θ2, and the interval t are appropriately adjusted so that the temperature at the edge of the metal thin plate 160 is close to the temperature of the flat portion, thereby being uniform in the width direction of the metal thin plate. You can have one temperature distribution.

8 is a schematic view of another embodiment of the apparatus for manufacturing a secondary battery electrode according to the present invention. The electrode manufacturing apparatus of this embodiment includes a takeout unit 210 for continuously supplying the metal thin plate 260 wound in a roll shape, and a plasma processing unit for surface treatment by spraying plasma gas onto the surface of the metal thin plate 260. 217, an active material applying unit 220 for applying the active material layer 265 to one surface of the unwrapped metal thin plate 260, a drying unit 230 for drying the active material layer applied to the metal thin plate, and an active material layer The winding-up part 216 which winds up this dried metal thin plate in roll form is included. The rollers 211-215 are idle rollers for guiding the transport of the thin metal plate 160.

9 is a top schematic view of the drying section of the apparatus of FIG. 8. In the present embodiment, the metal thin plate 260 coated with the active material is transferred to the right side, the active material 265 is coated at the center of the metal thin plate 260, and the active material is coated at the edge of the metal thin plate 260. Not. In addition, a pair of U-shaped inductive coupling coils 231 and 232 are alternately arranged so that the bent portion is crossed in the width direction of the metal thin plate in the opposite direction. Moreover, the U-shaped inductive coupling coil 233 is arrange | positioned along the conveyance direction of the metal thin plate 260 in the center part. Reference numerals 235, 236 and 237 denote the power source of each inductive coupling coil. The pair of inductive coupling coils 231 and 232 may be used to be bent or not bent upward near the edge of the metal sheet in the width direction.

FIG. 10 is an explanatory view showing a widthwise temperature distribution of A-A to E-E cross sections of a metal sheet heated by an inductive coupling coil in which both ends are not bent in FIG. 8. When the thin plate is heated by the inductive coupling coil in the U shape, the portion of the metal sheet corresponding to the bent (closed) end is heated more than the part of the metal sheet corresponding to the open side end of the U shape so that the temperature is increased. Becomes high. In other words, assuming that the metal thin plate is stationary, the temperature distribution in the width direction of the metal thin plate in the AA cross section of FIG. 9 is a U-shaped opening, as shown in the corresponding temperature distribution graph of FIG. In the upper part of 9, the bent end side is heated more than that of the right side of the graph of FIG. In addition, the temperature distribution in the width direction of the thin metal plate in the BB cross section of FIG. 9) is heated a lot and the temperature becomes high. In addition, in the CC cross section of FIG. 9, since the inductive coupling coil 233 is disposed along the conveying direction of the metal sheet, it is heated much at the center of the metal sheet and is heated at the edge thereof as shown in FIG. 10 (c). It will have the same temperature distribution.

In the case where the induction heating coil is arranged as shown in FIG. 9, when the metal sheet is transferred in the direction of the arrow, the temperature distribution of the metal sheet in the DD cross section overlaps the temperature distributions of FIGS. 10 (a) and 10 (b). The temperature distribution as shown in FIG. 10 (d) is shown. In addition, the temperature distribution in the E-E cross section of the thin metal plate shows the same temperature distribution as in FIG. 10 (e) in which the temperature distributions of FIG. 10 (d) and FIG. That is, according to the present invention, a plurality of inductive coupling coils are arranged such that the sum of the magnetic flux densities interlinking the metal thin plates with respect to the conveying length in the longitudinal direction of the metal thin plates is uniformly distributed along the width direction, thereby uniformly heating the metal thin plates. It is possible to prevent damage due to nonuniform thermal expansion. Further, the inductive coupling coil can be arranged so that the sum of the current densities induced by the magnetic flux that bridges the metal thin plates with respect to the transfer length of the metal thin plates is uniformly distributed along the width direction.

 In FIG. 9, when both ends of the U-shaped inductive coupling coils 231 and 232 are bent as shown in FIG. 4, the temperature distribution of the metal sheet corresponding to each of the cross sections AA to EE is shown in FIG. 11. It is like. That is, when both ends of the U-shaped inductive coupling coils 231 and 232 are bent, as shown in FIG. 11E, when both ends of the U-shaped inductive coupling coils 231 and 232 are not bent. The temperature distribution in the width direction more uniform than the temperature distribution (FIG. 10 (e)) can be obtained.

100 unwinding part
110 backup roller
120 active material coating unit
130 drying parts
131 inductive coupling coil
140 windings
160 metal lamination
165 active material layer
231, 231, 233 inductive coupling coil

Claims (13)

In the method of manufacturing an electrode for a secondary battery comprising an active material coating step of applying an active material layer on one surface of a metal thin plate, and a drying step of drying the active material layer,
The drying step,
Transferring the metal sheet in the longitudinal direction,
A secondary battery electrode characterized in that the active material is dried by induction heating of a thin metal sheet by an inductive coupling coil arranged so that the sum of magnetic flux densities interlinking the thin metal sheet with respect to the transfer length of the thin metal sheet is uniformly distributed along the width direction. Manufacturing method. The method of claim 1,
The inductive coupling coil is plural, each bent in a U shape,
The secondary battery is installed on the upper surface of the metal sheet so as to cross in the width direction of the metal sheet, and the neighboring inductive coupling coils are alternately installed such that the bent end portions of the U-shaped coils are located in opposite directions, respectively. Method for producing an electrode. 3. The method of claim 2,
Wherein each of the inductive coupling coils is bent such that end portions near both ends in the width direction of the thin metal plate are separated from the thin metal plate. 4. The method according to any one of claims 1 to 3,
The method of manufacturing an electrode for a secondary battery, further comprising the step of subjecting the surface of the metal thin plate to a plasma surface before applying the active material. An unwinding part for continuously supplying the thin metal sheet wound in the form of a roll; In the electrode manufacturing apparatus of the secondary battery comprising a winding portion for winding the thin metal plate dried in the active material layer in the form of a roll,
The drying unit includes:
An inductive coupling coil installed to cross the width direction of the metal sheet at a distance from one surface of the metal sheet;
A power source for applying an alternating voltage to the inductive coupling coil;
The inductive coupling coil is bent so that the vicinity of both ends of the width direction of the metal thin plate away from the metal thin plate, the electrode manufacturing apparatus of the secondary battery. 6. The method of claim 5,
The secondary battery electrode manufacturing apparatus further comprises a core provided on both sides in the width direction of the thin metal plate of the inductive coupling coil. The method according to claim 5 or 6,
The electrode manufacturing apparatus of the secondary battery further comprises a plasma processing unit for surface treatment by injecting a gas of the plasma state on at least one surface of the thin metal plate between the unwinding portion and the active material coating portion. An unwinding part for continuously supplying the thin metal sheet wound in the form of a roll; In the electrode manufacturing apparatus of the secondary battery comprising a winding portion for winding the thin metal plate dried in the active material layer in the form of a roll,
The drying unit includes:
A plurality of inductive coupling coils provided to traverse in the width direction of the metal sheet at a distance from one surface of the metal sheet;
A power source for applying an alternating voltage to the inductive coupling coil;
The plurality of inductive coupling coils are arranged such that the sum of magnetic flux densities interlinking the metal thin plates with respect to the conveying length of the metal thin plates conveyed in the longitudinal direction is uniformly distributed along the width direction. Manufacturing device. 9. The method of claim 8,
At least one of the plurality of inductive coupling coils is bent so that the vicinity of both ends in the width direction of the thin metal plate is separated from the thin metal plate. 10. The method of claim 9,
The electrode manufacturing apparatus of the secondary battery further comprises an inductive coupling coil arranged to heat along the conveying direction of the thin metal plate. 11. The method according to claim 9 or 10,
The electrode manufacturing apparatus of the secondary battery further comprises a plasma processing unit for surface treatment by injecting a gas of the plasma state on at least one surface of the thin metal plate between the unwinding portion and the active material coating portion. An unwinding part for continuously supplying the thin metal sheet wound in the form of a roll, an active material applying part for applying an active material layer to one surface of the unrolled metal thin plate, a drying part for drying the active material layer applied to the metal thin plate, In the electrode manufacturing apparatus of the secondary battery comprising a winding portion for winding the thin metal plate dried in the active material layer in the form of a roll,
The drying unit includes:
A plurality of inductive coupling coils provided to traverse in the width direction of the metal sheet at a distance from one surface of the metal sheet;
A power source for applying an alternating voltage to the inductive coupling coil;
The plurality of inductive coupling coils are bent in a U-shape, neighboring inductive coupling coils manufacturing method of the secondary battery electrode, characterized in that alternately installed so that the bent end of each of the U-shaped coil is located in the opposite direction. The method of claim 12,
The electrode manufacturing apparatus of the secondary battery further comprises a plasma processing unit for surface treatment by injecting a gas of the plasma state on at least one surface of the thin metal plate between the unwinding portion and the active material coating portion.

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