Manufacturing method of electrode for secondary battery

Abstract

A method for manufacturing an electrode for a secondary battery is disclosed. A method for manufacturing an electrode for a secondary battery according to one embodiment of the present invention comprises: a mixing unit in which an active material powder, a binder powder, and a conductive powder are supplied from an active material powder container, a binder powder container, and a conductive powder container, respectively, and a powder mixture composed of the active material powder, the binder powder, and the conductive powder is fiberized and automatically discharged by the frictional force of a rotating body rotating in one direction; a molding unit in which the fiber mixture automatically discharged from the mixing unit is formed into a film of a set shape; a pressurizing unit in which the film mixture formed from the molding unit is supplied and the thickness of the film mixture is uniformized through a pair of pressurizing rollers; a winding roll in which an electrode powder film formed from the pressurizing unit is wound to a predetermined length; and a base film roll interposed between the winding rolls, wherein among the winding rolls, a first electrode powder film wound on a first winding roll, a base film wound on a base film roll, and among the winding rolls, a second winding It includes a lamination unit that supplies second electrode powder films wound on a roll, and heats and cools the first electrode powder film, the substrate film, and the second electrode powder film in that order so that they are laminated and bonded.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing an electrode for a secondary battery, and more specifically, to a method for manufacturing an electrode for a secondary battery that can improve the energy density of the electrode and reduce material costs by manufacturing the electrode through a dry process that does not use a solvent. Background Technology

[0002] Generally, secondary batteries have been applied to small-scale fields such as mobile devices and laptop computers, but recently, the direction of research is expanding to medium and large-scale fields, and they are widely used in fields requiring high output, mainly in relation to energy storage systems (ESS) and electric vehicles (EV).

[0003] In the case of these medium-to-large rechargeable batteries, unlike small ones, not only are the operating environments (e.g., temperature, shock) harsh, but a larger number of batteries must also be used; therefore, safety must be ensured along with excellent performance or a reasonable price.

[0004] The aforementioned secondary batteries include not only lithium-ion batteries using liquid / polymer electrolytes, such as lithium-ion batteries, lithium-sulfur batteries, and lithium-metal batteries, but also all-solid-state batteries using solid electrolytes.

[0005] Since most currently commercialized lithium secondary batteries use organic liquid electrolytes in which lithium salts are dissolved in organic solvents, they carry potential risks of leakage, ignition, and explosion.

[0006] In fact, as explosion accidents involving products applying this are continuously being reported, it is urgent to resolve these issues.

[0007] If this is to be resolved using a separate safety device, there is a risk of energy density loss due to the significant weight of the said safety device, and fundamentally, there are inevitably limitations in overcoming safety issues as organic liquid electrolytes are used.

[0008] To solve the aforementioned problems, the development of all-solid-state batteries using solid electrolytes instead of liquid electrolytes is underway.

[0009] Since the above-mentioned all-solid-state battery does not contain flammable organic solvents, it has the advantage of being able to simplify safety devices and is recognized as a battery with excellent manufacturing costs and productivity.

[0010] In addition, the above-mentioned all-solid-state battery is expected to be a technology capable of manufacturing a stable, high-capacity, and high-output battery because it is easy to stack a junction structure in series comprising a pair of electrode layers including a positive electrode layer and a negative electrode layer, and a solid electrolyte layer interposed between these electrode layers.

[0011] In the conventional technology for manufacturing electrodes for secondary batteries as described above, a slurry is prepared by mixing a powder composed of an active material, a binder, and a conductive material with a solvent.

[0012] Next, the above-mentioned slurry is manufactured through a wet method in which it is coated and dried, and then a process is carried out to increase the density of the electrode through a rolling process.

[0013] However, the method for manufacturing electrodes for secondary batteries according to the prior art has limitations in increasing the thickness of the coating because the slurry spreads (spreadability) or, during the drying process, the binder lifts up due to convection caused by hot air drying in the drying oven.

[0014] Accordingly, research and development on the manufacture of electrodes for secondary batteries is necessary to solve the aforementioned problems.

[0015] The matters described in this background technology section are written to enhance understanding of the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. The problem to be solved

[0016] An embodiment of the present invention aims to provide a method for manufacturing an electrode for a secondary battery, wherein the thickness of the electrode can be controlled by applying a dry process during the manufacture of the electrode, thereby increasing the electrode filling rate and improving the energy density of the electrode. means of solving the problem

[0017] In one or more embodiments of the present invention, an active material powder, a binder powder, and a conductive powder are supplied from an active material powder container, a binder powder container, and a conductive powder container, respectively, and a mixing unit that fiberizes and automatically discharges a powder mixture composed of the active material powder, the binder powder, and the conductive powder by the frictional force of a rotating body rotating in one direction; a molding unit that forms a film of the fiber mixture automatically discharged from the mixing unit into a set shape; a pressurizing unit that supplies the film mixture formed from the molding unit and uniformizes the thickness of the film mixture through a pair of pressurizing rollers; a winding roll that winds an electrode powder film formed from the pressurizing unit to a predetermined length; and a base film roll interposed between the winding rolls, wherein among the winding rolls, a first electrode powder film wound on a first winding roll, a base film wound on a base film roll, and among the winding rolls, a second winding roll A manufacturing system for an electrode for a secondary battery can be provided, comprising a lamination unit that heats and cools the first electrode powder film, a substrate film, and the second electrode powder film in that order while supplying the second electrode powder film respectively, so that they are laminated and bonded.

[0018] Additionally, the mixing unit may include a mixing container formed in a long tubular shape so that the active material powder, binder powder, and conductive material powder are supplied into the interior through a hopper mounted on one side of the front upper portion, and the rear end is formed in a tapered shape with a reduced diameter, and the discharge port for discharging the fiber mixture is formed in a slot shape; and a screw installed along the longitudinal direction inside the mixing container and rotated in one direction by a driving motor to fiberize the supplied binder powder and generate binding force between the active material powder and between the active material powder and between the active material powder and the conductive material powder.

[0019] In addition, the screw may be characterized by having an overall diameter that gradually increases so that the distance from the inner surface of the mixing container becomes closer as it moves towards the rear.

[0020] In addition, the mixing unit may further include a preheating chamber that applies heat to the powder mixture inside while covering a certain area of ​​the outer surface of one rear side of the mixing container.

[0021] In addition, the molding unit is configured at the rear end of the mixing container and can form a fiber mixture automatically discharged from the mixing container into a set shape through a molding die connected to the discharge port.

[0022] In addition, the molding die is composed of an upper die and a lower die and is detachable, and the shape of the fiber mixture can be varied through the molding groove between the upper die and the lower die.

[0023] Additionally, the mixing unit may include a mixing container formed in a sealed box shape into which the active material powder, binder powder, and conductive powder are supplied; a rotating body that rotates inside the mixing container by means of a driving motor installed outside the mixing container to fiberize the binder powder and dryly disperse the active material powder and conductive powder; and a feeder connected to the mixing container through a connecting pipe and configured to discharge a certain amount of the fiber mixture formed by the rotating body through a slot-shaped discharge line formed at the bottom.

[0024] In addition, the rotating body may include a blade that maintains a certain gap with the inner surface of the mixing container.

[0025] In addition, the discharge line may have a slot length greater than the width of the winding roll.

[0026] Additionally, the molding unit may include a pair of molding rollers configured to correspond to the discharge line of the feeder and forming a film by compressing a fiber mixture supplied in a certain amount from the feeder from both sides, and a pressure cylinder configured to correspond to one of the pair of molding rollers and pushing the one molding roller toward the other molding roller.

[0027] In addition, it may further include a cutting unit configured between the molding unit and the pressurizing unit, which uniformly cuts both longitudinal edges of a film mixture transferred from the molding unit to the pressurizing unit.

[0028] In addition, the lamination unit may be configured in the front based on the direction in which the first electrode powder film, the substrate film, and the second electrode powder film are stacked and transported in sequence, and may include a heating unit that forms adhesion to the respective binders within the first electrode powder film and the second electrode powder film.

[0029] Additionally, the lamination unit may include a heating unit that heats a base film wound from the base film roll to form adhesion, and a cooling unit that cools the first electrode powder film and the second electrode powder film laminated by the adhesion of the base film, wherein the heated base film is supplied to be interposed between the first electrode powder film and the second electrode powder film.

[0030] In addition, in one or more embodiments of the present invention, a method for manufacturing an electrode for a secondary battery using a manufacturing system for a secondary battery comprises: a first step of supplying an active material powder, a binder powder, and a conductive material powder to a mixing unit and mixing each powder through the mixing unit to form fibers; a second step of supplying the fiber mixture formed through the mixing unit to a molding unit and forming the fiber mixture into a film by generating a shear force between the fiber mixtures by the frictional force of a pressurizing body of the molding unit; a third step of supplying the film mixture formed through the molding unit to a pressurizing unit and uniformizing the thickness of the film mixture through a pair of pressurizing rollers of the pressurizing unit; a fourth step of winding an electrode powder film formed from the pressurizing unit onto a winding roll for a predetermined length; and, with a base film roll interposed between the winding rolls, a first electrode powder film wound on a first winding roll, and a base film rolled A method for manufacturing an electrode for a secondary battery can be provided, comprising the fifth step of supplying a base film and a second electrode powder film wound on a second winding roll to a lamination unit while winding each of them, and forming an electrode for a secondary battery by bonding the first electrode powder film, the base film, and the second electrode powder film through the lamination unit while heating and cooling.

[0031] Additionally, the first step may include the step of supplying an active material powder, a binder powder, and a conductive powder to the mixing container of the mixing unit, respectively, and the step of generating binding force between the active material powder and the active material powder and between the active material powder and the conductive powder while decomposing the binder powder between the mixing container and the rotating body inside the mixing container.

[0032] Additionally, between the second and third steps, the method may further include a step of uniformly cutting both longitudinal sides of the film mixture formed from the molding unit through a cutting unit.

[0033] Additionally, the fifth step may include forming winding rolls consisting of the first winding roll and the second winding roll, positioning a base film roll between the first winding roll and the second winding roll, winding the first electrode powder film, the base film, and the second electrode powder film respectively from the first winding roll, the base film roll, and the second winding roll, and heating and cooling the films stacked in the order of the first electrode powder film, the base film, and the second electrode powder film through the lamination unit to bond them together.

[0034] In addition, after the fifth step, the method may further include a step of winding the films laminated in the order of the first electrode powder film, the substrate film, and the second electrode powder film onto a secondary battery electrode roll of a certain length. Effects of the invention

[0035] The manufacturing system and method for a secondary battery electrode according to an embodiment of the present invention manufacture the secondary battery electrode using a dry process, thereby enabling control of the electrode thickness, which in turn increases the filling rate and improves the energy density of the electrode.

[0036] In addition, the manufacturing system and method for a secondary battery electrode according to an embodiment of the present invention can control the thickness of the electrode, thereby reducing material costs by reducing the use of a substrate and a separator during the manufacturing of a secondary battery.

[0037] Furthermore, other effects that can be obtained or predicted by the embodiments of the present invention will be disclosed directly or implicitly in the detailed description of the embodiments of the present invention. That is, various effects predicted according to the embodiments of the present invention will be disclosed within the detailed description to be set forth below. Brief explanation of the drawing

[0038] FIG. 1 is a schematic overall configuration diagram of a manufacturing system for an electrode for a secondary battery according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of a mixing unit and a molding unit applied to a manufacturing system for an electrode for a secondary battery according to an embodiment of the present invention. FIG. 3 is a configuration diagram of a cutting unit applied to a manufacturing system for a secondary battery electrode according to an embodiment of the present invention. FIGS. 4 and FIGS. 5 are configuration diagrams of a lamination unit applied to a manufacturing system for an electrode for a secondary battery according to an embodiment of the present invention. FIG. 6 is a schematic overall configuration diagram of a manufacturing system for an electrode for a secondary battery according to another embodiment of the present invention. FIG. 7 is a configuration diagram of a molding unit applied to a manufacturing system for an electrode for a secondary battery according to another embodiment of the present invention. FIG. 8 is a flowchart illustrating a method for manufacturing an electrode for a secondary battery according to embodiments of the present invention. Specific details for implementing the invention

[0039] Hereinafter, embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0040] To clearly explain the present invention, parts unrelated to the description have been omitted, and throughout the specification, identical or similar components are described using the same reference numerals.

[0041] In addition, the classification of the names of the components in the following description as "1st," "2nd," etc., is intended to distinguish them because their names are identical, and is not necessarily limited to that order.

[0042] FIG. 1 is a schematic overall configuration diagram of a manufacturing system for a secondary battery electrode according to an embodiment of the present invention, and FIG. 2 is a configuration diagram of a mixing unit and a molding unit applied to a manufacturing system for a secondary battery electrode according to an embodiment of the present invention.

[0043] In an embodiment of the present invention, the front-back, left-right, and up-down directions are set as reference directions based on Figure 1.

[0044] The definition of the reference direction as described above is relative, and since the direction may vary depending on the reference position of the system or the reference position of the manufactured product, the reference direction described above is not necessarily limited to the reference direction of this embodiment.

[0045] Accordingly, in an embodiment of the present invention, the mixing unit (10) side is defined as the front, the electrode roll (85) side is defined as the rear, the front and rear directions are set as reference directions, the part facing upward is defined as the upper, upper, upper surface, and upper part, and the part facing downward is defined as the lower, lower, lower surface, and lower part.

[0046] Furthermore, the term (one side / one end or the other side / one end) below may be defined as an end of one side, or may be defined as a certain part (one side / one end or the other side / one end) that includes that end.

[0047] The manufacturing system and apparatus for a secondary battery electrode according to an embodiment of the present invention are intended to manufacture a secondary battery electrode through a dry process instead of a conventional wet process.

[0048] The aforementioned secondary batteries include not only lithium-ion batteries using liquid / polymer electrolytes, such as lithium-ion batteries, lithium-sulfur batteries, and lithium-metal batteries, but also all-solid-state batteries using solid electrolytes.

[0049] In the embodiments of the present invention, only active material powder, binder powder, and conductive material powder are used to manufacture electrodes before being impregnated into various materials.

[0050] To this end, with reference to FIG. 1 and FIG. 2, a manufacturing system for an electrode for a secondary battery according to an embodiment of the present invention includes a mixing unit (10), a molding unit (20), a cutting unit (30), a pressurizing unit (40), a winding roll (50), and a lamination unit (60).

[0051] The above mixing unit (10) includes a mixing container (11) in which an active material powder, a binder powder, and a conductive powder are supplied and stored from an active material powder container (1a), a binder powder container (1b), and a conductive powder container (1c), respectively.

[0052] In this case, the above conductive powder may be a solid electrolyte powder in the case of an all-solid-state battery.

[0053] The above mixing container (11) has a circular cross-section and can be formed in a long tubular shape.

[0054] In addition, the rear end of the mixing container (11) is formed in a tapered shape so that the cross-sectional area of ​​a certain length gradually decreases as it goes toward the rear.

[0055] An outlet (13) is formed at the end of the above mixing container (11), and the outlet (13) is formed as a slot of a certain length.

[0056] That is, the above mixing container (11) has a cross-sectional area of ​​a certain length at the rear end that gradually decreases and has a slot outlet (13).

[0057] A rotating body (15) is mounted inside such a mixing container (11), and the rotating body (15) may include a screw.

[0058] At this time, the screw is arranged lengthwise inside the mixing container (11) and is connected so as to be rotatable by a driving motor (M).

[0059] In addition, the overall diameter of the screw is formed to increase towards the rear, and as a result, the gap between the screw and the inner surface of the mixing container (11) becomes progressively smaller towards the rear.

[0060] That is, the above mixing container (11) is structured such that as it moves towards the rear inside, the active material powder, binder powder, and conductive material powder receive a greater frictional force between themselves and the screw.

[0061] This mixing unit (10) is configured to mix the active material powder, binder powder, and conductive material powder inside the mixing container (11) to form a powder mixture, and to fiberize the powder mixture by rotating the screw to form a fiber mixture.

[0062] That is, as the screw rotates, the binder powder is decomposed, and as the binder powder is decomposed, a binding force is generated between the active material powder and the active material powder, and between the active material powder and the conductive material powder, respectively.

[0063] At this time, if the above secondary battery is a solid-state battery, a binding force may be generated between the solid electrolyte powder and the conductive powder, and between the solid electrolyte powder and the active material powder, respectively.

[0064] The above mixing unit (10) has a structure in which, as the screw rotates, the powder mixture moves along the mixing container (11) and gradually transforms into a fiber mixture, and when there is no more space to receive, the fiber mixture is automatically discharged through the discharge port (13).

[0065] At this time, the shape of the fiber mixture changes according to the shape of the discharge port (13).

[0066] In other words, the shape of the fiber mixture is determined in correspondence with the width or length of the outlet (13).

[0067] And the above mixing unit (10) includes a preheating chamber (17) that surrounds the outer surface on one side of the rear part of the mixing container (11).

[0068] The above preheating chamber (17) is formed to surround a certain portion of the outer surface of the mixing container (11), and is intended to apply heat to easily convert the powder mixture into a fiber mixture when the powder mixture is fiberized.

[0069] These preheating chambers (17) can be operated selectively as needed, depending on the type of powder mixture.

[0070] For example, the preheating chamber (17) may include a heating coil that surrounds the outer surface of the mixing container (11).

[0071] A molding unit (20) is configured at the rear of the above-mentioned mixing unit (10).

[0072] The molding unit (20) serves to form a film from the fiber mixture formed from the mixing unit (10).

[0073] The molding unit (20) is configured to correspond to the rear end of the mixing container (11) and forms the fiber mixture into a film by varying its shape while applying pressure through a molding die (21) connected to the discharge port (13).

[0074] Here, the molding die (21) may be composed of an upper die (23) and a lower die (25).

[0075] Furthermore, the molding die (21) is configured such that a molding groove (27) between an upper die (23) and a lower die (25) is connected to the discharge port (13), and a fiber mixture automatically discharged from the discharge port (13) is compressed as it passes through the molding groove (27), which has a cross-sectional area smaller than that of the discharge port (13), and is formed into a film according to the shape of the molding groove (27).

[0076] At this time, the fiber mixture is formed into a film-shaped film mixture (71) as shear force is generated between them.

[0077] A cutting unit (30) is configured at the rear of the above-mentioned forming unit (20).

[0078] FIG. 3 is a configuration diagram of a cutting unit applied to a manufacturing system for an all-solid-state electrode according to an embodiment of the present invention.

[0079] FIG. 3 shows a top view of the cutting unit (30).

[0080] Referring to FIG. 3, both edges of the film mixture (71) automatically discharged from the molding unit (20) are uniformly cut.

[0081] This cutting unit (30) cuts the uneven edge portions of the electrode (80) for a secondary battery to be manufactured, and cutter blades (31) are formed on both sides corresponding to the width of the electrode (80) for the secondary battery, and uniformly cuts both edges of the film mixture (71) that is automatically discharged from the molding unit (20).

[0082] The cutter blade (31) of the above cutting unit (30) can cut the film mixture (71) by rotating both cutter blades (31) simultaneously with respect to the rotation axis (33).

[0083] A pressurizing unit (40) is configured at the rear of the above-mentioned cutting unit (30) (see FIG. 1).

[0084] The above-mentioned pressure unit (40) includes a pair of pressure rollers (41).

[0085] The above-mentioned pressurizing unit (40) presses the film mixture (71), in which the edge portion is uniformly cut from the above-mentioned cutting unit (30), in the thickness direction, and uniformizes the thickness of the film mixture (71) to form an electrode powder film (70).

[0086] This pressurizing unit (40) can change the thickness of the film mixture (71) by adjusting the gap between the pair of pressurizing rollers (41).

[0087] A winding roll (50) is positioned at the rear of the above-mentioned pressurizing unit (40).

[0088] The above winding roll (50) refers to a unit that winds the electrode powder film (70) that has passed through the above pressurizing unit (40) to a set length.

[0089] A cutter (not shown) is installed in front of the winding roll (50), and when the electrode powder film (70) is wound onto the winding roll (50) for a set length, the electrode powder film (70) is cut.

[0090] A lamination unit (60) is positioned at the rear of the aforementioned winding roll (50).

[0091] FIGS. 4 and FIGS. 5 are configuration diagrams of a lamination unit applied to a manufacturing system for an all-solid-state electrode according to an embodiment of the present invention.

[0092] Referring to FIG. 4, winding rolls (50a, 50b) and one substrate film roll (55) are arranged in front of the lamination unit (60).

[0093] In the above lamination unit, a first electrode powder film (70a) wound on the first winding roll (50a) among the winding rolls (50a, 50b), a base film (75) wound on the base film roll (55), and a second electrode powder film (70b) wound on the second winding roll (50b) among the winding rolls (50a, 50b) are each wound and supplied with a base film (75) interposed between the first electrode powder film (70a) and the second electrode powder film (70b).

[0094] At this time, a guide roller (61) is configured so that the first electrode powder film (70a), the base film (75), and the second electrode powder film (70b) are overlapped and laminated in that order.

[0095] This lamination unit (60) includes a heating unit (63).

[0096] The heating unit (63) applies heat to the first electrode powder film (70a), base film (75), and second electrode powder film (70b) stacked in sequence, thereby imparting adhesiveness to the binder contained in each of the first and second electrode powder films (70a, 70b), so that the first electrode powder film (70a), base film (75), and second electrode powder film (70b) are bonded together by the adhesiveness.

[0097] At this time, the heating unit (63) can apply heat in a range of 50°C or higher and 150°C or lower.

[0098] Meanwhile, the above lamination unit (60) may be structured as follows.

[0099] Referring to FIG. 5, the lamination unit (60) has the heating unit (63) positioned at the rear of the substrate film roll (55) to heat the substrate film (75) first.

[0100] The heated base film (75) is interposed between the first electrode powder film (70a) and the second electrode powder film (70b), and the binder contained in each of the first electrode powder film (70a) and the second electrode powder film (70b) is bonded to each other by the heated base film (75) to impart adhesiveness.

[0101] At this time, the heating unit (63) can apply heat in a range of 50°C or higher and 150°C or lower.

[0102] In addition, the lamination unit may further include a cooling unit (65) together with the heating unit (63).

[0103] The cooling unit (65) cools the first electrode powder film (70a), base film (75), and second electrode powder film (70b) bonded while passing through the heating unit (63) at a temperature of 5°C or higher and 10°C or lower to complete the electrode (80) for the secondary battery.

[0104] FIG. 6 is a configuration diagram of a mixing unit and a molding unit applied to a manufacturing system for an all-solid-state electrode according to another embodiment of the present invention, and FIG. 7 is a configuration diagram of a molding unit applied to a manufacturing system for an electrode for a secondary battery according to another embodiment of the present invention.

[0105] Referring to FIG. 6, a secondary battery electrode manufacturing system according to another embodiment of the present invention includes a mixing unit (100), a molding unit (200), a pressurizing unit (400), a winding roll (50), and a lamination unit (60).

[0106] The above mixing unit (100) includes a mixing container (110) in which an active material powder, a binder powder, and a conductive material powder are each supplied and stored.

[0107] At this time, a blade (111), which is a rotating body, is installed inside a mixing container (110) applied to a secondary battery electrode manufacturing system according to another embodiment of the present invention so as to rotate by a driving motor (M).

[0108] The blade (111) is connected to a drive motor (M) located at the top of the mixing container (110) and configured to rotate inside the mixing container (110).

[0109] The blade (111) rotates while maintaining a certain gap with the inner surface of the mixing container (110).

[0110] This mixing unit (100) is configured such that the active material powder, binder powder, and conductive material powder are mixed inside the mixing container (110) to form a powder mixture, and the powder mixture is fiberized by the rotation of the blade (111) to form a fiber mixture.

[0111] That is, as the blade (111) rotates, the binder powder is decomposed, and as the binder powder is decomposed, a binding force is generated between the active material powder and the active material powder, and between the active material powder and the conductive powder.

[0112] In addition, a feeder (117) is connected to the above-mentioned mixing container (110) through a connecting pipe (115).

[0113] The feeder (117) discharges a certain amount of the fiber mixture formed from the mixing unit (100).

[0114] In this feeder (117), the fiber mixture is introduced through a connecting pipe (115) connected to the top, and the cross-sectional area is formed to become narrower as it goes downward, and has a slot-shaped discharge line (117) at the bottom.

[0115] The discharge line (117) above can be formed with a slot length greater than the width of the winding roll (50), which will be described below.

[0116] Referring to FIG. 7, a molding unit (200) applied to a secondary battery electrode manufacturing system according to another embodiment of the present invention includes a molding roller (210) and a pressure cylinder (211).

[0117] A pair of the above-mentioned forming rollers (210) are installed on both sides of the discharge line (117) of the feeder (117).

[0118] The above-mentioned molding roller (210) is intended to compress a certain amount of fiber mixture discharged through the discharge line (117) from both sides of the discharge line (117) to form a film.

[0119] The gap between these pair of forming rollers (210) can be maintained constant by a pressure cylinder (211).

[0120] That is, the pressure cylinder (211) is configured to operate in correspondence with one side forming roller (210a) of the pair of forming rollers (210), and presses the one side forming roller (210a) so that a pressing force is generated toward the other side forming roller (210b) to which the one side forming roller (210a) is fixed.

[0121] In addition, the pressure cylinder (211) acts as a damper when the fiber mixture passes between the pair of molding rollers (210).

[0122] A cutting unit (300) is configured at the rear of a molding unit (200) applied to a manufacturing system for a secondary battery electrode according to another embodiment of the present invention, and a pressurizing unit (400) is configured at the rear of the cutting unit (300).

[0123] The cutting unit (300) may have the same configuration as described in FIG. 3, and the pressurizing unit (400) may have the same configuration as described in FIG. 4 and FIG. 5.

[0124] A method for manufacturing a secondary battery electrode (80) using a secondary battery electrode manufacturing system according to embodiments of the present invention is as follows.

[0125] FIG. 8 is a flowchart showing a method for manufacturing an electrode for a secondary battery according to an embodiment of the present invention.

[0126] Referring to FIG. 8, first, an active material powder, a binder powder, and a conductive material powder are each supplied to a mixing container (11) to form a powder mixture (S1).

[0127] At the same time, the binder powder is decomposed through the screw or blade (111) inside the mixing container (11), and a binding force is generated between the active material powder and between the active material powder and the conductive material powder to form the powder mixture into a fiber mixture (S2).

[0128] The fiber mixture formed through the above mixing unit (10) is supplied to the molding unit (20).

[0129] At this time, the fiber mixture can be automatically supplied to the molding unit (20) by the operation of the screw, and a certain amount can be supplied to the molding unit (20) by the feeder (117).

[0130] Next, shear force is generated between the fiber mixtures through the molding unit (20) to form the fiber mixtures into a film (S3).

[0131] At this time, the molding unit (20) is composed of a molding die (21) or a molding roller (210) and pressurizes the supplied fiber mixture to form a film-shaped film mixture (71).

[0132] Both edges of the film mixture (71) formed from the molding unit (20) are uniformly cut through the cutting unit (30) (S4).

[0133] Next, the film mixture (71) is supplied to a pressurizing unit (40) to equalize the thickness of the film mixture (71) (S5).

[0134] The film mixture (71) passes between a pair of pressure rollers (41) of the above-mentioned pressure unit (40), and its thickness is made uniform.

[0135] The above electrode powder film (70) is wound onto a winding roll (50) for a certain length (S6).

[0136] Next, with the base film roll (55) interposed between the two winding rolls (50a, 50b), the first electrode powder film (70a) wound on the first winding roll (50a), the base film (75) wound on the base film roll (55), and the second electrode powder film (70b) wound on the second winding roll (50b) are each wound and supplied to the lamination unit (60) (S7).

[0137] At this time, the first electrode powder film (70a), the base film (75), and the second electrode powder film (70b) are laminated in that order.

[0138] Next, the first electrode powder film (70a), the base film (75), and the second electrode powder film (70b) are bonded while heating and cooling through the lamination unit (60) to form an electrode (80) for a secondary battery.

[0139] At this time, the first electrode powder film (70a), base film (75), and second electrode powder film (70b) laminated together can be heated at once through the heating part (63) of the lamination unit (60).

[0140] Alternatively, the substrate film (75) may be heated through the heating section (63) of the lamination unit (60), and then laminated with the heated substrate film (75) interposed between the first electrode powder film (70a) and the second electrode powder film (70b), and then cooled through the cooling section (65).

[0141] Finally, the films laminated in the order of the first electrode powder film (70a), the base film (75), and the second electrode powder film (70b) are wound onto a secondary battery electrode roll (85) of a certain length (S8).

[0142] A secondary battery electrode (80) wound on the secondary battery electrode roll (85) can be formed into a set shape and impregnated with a liquid / polymer electrolyte to form a lithium-ion battery or a solid-state battery by transferring it to a solid-state electrolyte.

[0143] Accordingly, the manufacturing system and manufacturing method for a secondary battery electrode according to an embodiment of the present invention can control the thickness of the electrode (80) by manufacturing the secondary battery electrode (80) using a dry process, thereby increasing the filling rate of the electrode (80) and improving the energy density of the electrode (80).

[0144] In addition, the manufacturing system and method for a secondary battery electrode according to an embodiment of the present invention may reduce material costs by reducing the use of a substrate and a separator when manufacturing a secondary battery by adjusting the thickness of the electrode (80).

[0145] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art will understand that various modifications and changes can be made to the invention without departing from the spirit and scope of the invention as described in the following claims. Explanation of the symbols

[0146] 1a: Active material powder container 1b: Binder powder container 1c: Conductive powder container 10, 100: Mixing unit 11, 110: Mixing container 13: Discharge port 15: Rotating body 17: Preheating chamber 20, 200: Molding Unit 21: Molding Die 23: Upper frame 25: Lower frame 27: Forming groove 30, 300: Cutting unit 31: Cutter blade 33: Rotating shaft 40, 400: Pressurizing unit 41: Pressurizing roller 50, 500: Winding roll 55: Base film roll 60: Lamination unit 61: Guide roller 63: Heating section 65: Cooling section 70: Electrode powder film 70a: First electrode powder film 70b: Second electrode powder film 71: Film mixture 75: Base film 80: Electrode for secondary battery 85: Electrode Roll 111: Blade 115: Connector 117: Feeder 119: Discharge line 210: Forming roller 211: Pressurized cylinder

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 A method for manufacturing an electrode for a secondary battery comprises: a first step of supplying an active material powder, a binder powder, and a conductive material powder to a mixing unit and mixing each powder through the mixing unit to form fibers; a second step of supplying the fiber mixture formed through the mixing unit to a molding unit and forming the fiber mixture into a film by generating a shear force between the fiber mixtures by the frictional force of a pressurizing body of the molding unit; a third step of supplying the film mixture formed through the molding unit to a pressurizing unit and uniformizing the thickness of the film mixture through a pair of pressurizing rollers of the pressurizing unit; and a fourth step of winding the electrode powder film formed from the pressurizing unit onto a winding roll for a predetermined length. A fifth step comprising: forming an electrode for a secondary battery by bonding the first electrode powder film wound on the first winding roll, the base film wound on the base film roll, and the second electrode powder film wound on the second winding roll while winding them respectively, with a base film roll interposed between the winding rolls; wherein the first electrode powder film, the base film, and the second electrode powder film are bonded while heating and cooling through the lamination unit; wherein the first step comprises the step of supplying an active material powder, a binder powder, and a conductive material powder respectively to a mixing container of the mixing unit, and the step of generating a binding force between the active material powder and the active material powder and between the active material powder and the conductive material powder while decomposing the binder powder between the mixing container and a rotating body inside the mixing container; and wherein the fifth step comprises the first winding roll and the second winding A method for manufacturing an electrode for a secondary battery, comprising the steps of forming winding rolls made of rolls, positioning a base film roll between the first winding roll and the second winding roll, winding a first electrode powder film, a base film, and a second electrode powder film respectively from the first winding roll, the base film roll, and the second winding roll, and heating and cooling the films stacked in the order of the first electrode powder film, the base film, and the second electrode powder film through the lamination unit to bond them together. Claim 15 delete Claim 16 A method for manufacturing an electrode for a secondary battery according to claim 14, further comprising the step of uniformly cutting both longitudinal sides of a film mixture formed from a molding unit through a cutting unit between the second and third steps. Claim 17 delete Claim 18 A method for manufacturing an electrode for a secondary battery according to claim 14, further comprising, after the fifth step, a step of winding films laminated in the order of the first electrode powder film, the substrate film, and the second electrode powder film onto a secondary battery electrode roll of a predetermined length.

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