Apparatus or method for manufacturing double-sided electrode plate and double-sided electrode plate manufactured thereby

Abstract

One embodiment of the present invention provides an apparatus for manufacturing a double-sided electrode plate, the apparatus comprising: a transfer unit for transferring a belt; a first powder application unit for applying a first powder on the transferred belt; a first flattening unit for flattening the applied first powder; a current collector stacking unit for stacking a current collector on the flattened first powder; a second powder application unit for applying a second powder on the stacked current collector; a second flattening unit for flattening the applied second powder; and a pressing unit for pressing a stack in which the first powder, the current collector, and the second powder are stacked.

Description

Apparatus or method for manufacturing a double-sided electrode plate and a double-sided electrode plate manufactured thereby

[0001] The present invention relates to a manufacturing process for an electrode, which is a core component of an electrochemical energy storage device. More specifically, it provides a technology for forming a high-performance electrode by applying active material powder to both sides of a current collector using a dry coating process and compressing them.

[0002] Lithium-ion batteries are used as a core energy source in various fields, including electric vehicles (EVs), energy storage systems (ESS), and portable electronic devices, and active research is underway to maximize their performance and production efficiency. The quality of electrodes is crucial for enhancing battery durability and performance, and high-quality electrode plate manufacturing technology is a key technology in the manufacturing process of electrochemical energy storage devices, particularly lithium-ion batteries.

[0003] The traditional method of manufacturing electrode plates is based on a wet process. In this process, an active material is mixed with an organic solvent to form a slurry, coated onto a current collector, dried, and then compressed to complete the electrode. Although the wet process is still widely used, it has several limitations. The biggest problem is the complexity and inefficiency of the process. Not only are the slurry preparation and coating processes complex, but a significant amount of time and energy is consumed during the drying process after coating. This increases production costs and slows down the process speed, making mass production difficult.

[0004] Furthermore, organic solvents used in wet processes emit volatile organic compounds (VOCs), which can have a negative impact on the environment; consequently, manufacturers must establish solvent recovery and treatment facilities, incurring additional costs. In addition, if the viscosity of the slurry is not consistently maintained in the wet process, problems may arise where the active material is not evenly distributed across the current collector. This can lead to a degradation in electrode quality, resulting in lower battery energy density or reduced performance and durability.

[0005] To overcome these limitations, a dry coating process is being utilized. Dry coating involves directly applying and compressing active material in powder form onto a current collector instead of using a slurry; it is simpler and more efficient than the wet process. Since the dry process does not require a drying step, production speeds are faster, and energy consumption and costs are significantly reduced. Furthermore, because organic solvents are not used, environmental issues can be minimized. The powdered active material can be recovered and reused via a vacuum suction method, thereby reducing resource waste.

[0006] Recently, double-sided electrode technology has been gaining attention as an alternative to single-sided electrodes to increase electrode energy density. Double-sided electrode plates allow for the storage of more energy within the same surface area by coating active materials on both sides of the current collector. This enables increased battery capacity and offers the advantage of reducing weight and costs by decreasing the amount of current collector used. Double-sided electrodes are particularly useful in fields requiring high capacity, such as electric vehicles.

[0007] Double-sided electrode manufacturing technology plays a crucial role in ensuring electrode density and consistency while simultaneously reducing manufacturing costs. Advancements in this technology can significantly contribute to increasing the efficiency of the battery industry and implementing eco-friendly manufacturing processes.

[0008] In conventional electrode manufacturing processes, compression is performed by passing the electrode through calendering rolls multiple times, or requires repeating a separate process for each side for double-sided coating, resulting in inefficiencies. This leads to reduced production speed, increased process complexity, and higher manufacturing costs and time.

[0009] In conventional single-sided or complex double-sided processes, the process of applying active material onto a current collector, drying it, and then compressing it must be performed repeatedly. In particular, when coating active material on both sides, not only is it difficult to ensure a uniform coating on each side, but quality issues with the final electrode plate may also arise due to alignment or balance problems between processes. This results in reduced productivity and increased costs, making it a critical challenge to resolve these issues in large-scale battery manufacturing environments.

[0010] This invention aims to solve these problems by simultaneously completing electrode plates coated with active materials on both sides through a single compression process. This allows for a significant reduction in process steps, shortened processing time, and maximized production efficiency. Furthermore, since the coating and compression of the double-sided electrodes are performed simultaneously, the density and uniformity of the active material are enhanced, enabling the manufacture of high-performance electrode plates with improved energy density. This contributes to improving the performance and stability of the battery and offers the advantages of reducing production costs and minimizing resource waste.

[0011] Therefore, the core objective of the present invention is to manufacture double-sided electrode plates in a single compression process to maximize process efficiency, ensure uniform electrode quality, and reduce costs and time. Through this, high-performance, high-density double-sided electrodes can be stably produced, and the requirements of high-capacity energy storage devices, such as electric vehicles and energy storage systems, can be met.

[0012] To achieve the above technical objective, a double-sided electrode plate manufacturing device according to one embodiment of the present invention may include a conveying unit for conveying a protective material by a belt, a first powder application unit for applying a first powder onto the conveyed protective material, a first flattening unit for flattening the applied first powder, a current collector stacking unit for stacking a current collector onto the flattened first powder, a second powder application unit for applying a second powder onto the stacked current collector, a second flattening unit for flattening the applied second powder, a compression unit for compressing a laminate in which the protective material, the first powder, the current collector, and the second powder are stacked, and a protective material peeling unit for peeling off the protective material.

[0013] In an embodiment of the present invention, the protective material may be formed from one or more materials selected from transition metals or resins.

[0014] In an embodiment of the present invention, the first flattening unit may include at least one ultrasonic radiating unit.

[0015] In an embodiment of the present invention, the first leveling unit comprises a guard belt disposed on both sides of the ultrasonic radiating unit and controlling the loading interval of the powder; and a recovery unit disposed on one side of the guard belt, wherein the recovery unit can recover the remaining first powder guided in the other direction by the guard belt during the leveling process using the first leveling unit.

[0016] In an embodiment of the present invention, when the length from the starting point to the end point of the guard belt is defined as lt with respect to the conveying direction of the first powder, the first flattening part may be positioned in an area between 5% and 80% of the length of lt.

[0017] In an embodiment of the present invention, the ultrasonic radiating unit includes first to third ultrasonic radiating units spaced apart from each other along the conveying direction of the first powder, and the first to third ultrasonic radiating units may have different ultrasonic radiating gaps.

[0018] In an embodiment of the present invention, the conveying unit comprises a plurality of rollers for conveying the belt, wherein the plurality of rollers comprises: a first roller disposed adjacent to the first powder application unit; a fourth roller disposed adjacent to the end of the compression unit; a second roller disposed between the first and second flattening units; and a third roller disposed between the second flattening unit and the fourth roller; wherein the first and fourth rollers are disposed at a first height, and the second and third rollers may be disposed at a second height higher than the first height.

[0019] In an embodiment of the present invention, the compression part includes a belt member, and the belt member and the belt of the conveying part can compress a certain area of ​​the upper and lower surfaces of the laminate.

[0020] In an embodiment of the present invention, the belt member may be formed of one or more materials among transition metals or resins.

[0021] In an embodiment of the present invention, the compression part includes at least one heater, and the temperature of the compression part may gradually increase and then decrease as it moves in the conveying direction.

[0022] In an embodiment of the present invention, the pressure provided by the compression part to the laminate may gradually increase and then decrease as it moves in the conveying direction.

[0023] In an embodiment of the present invention, the device may further include a protective material supply unit disposed on one side of the belt and supplying the protective material to the conveying unit; and a protective material recovery unit disposed on the other side of the belt and recovering the protective material.

[0024] In an embodiment of the present invention, a purification unit may be further included that is disposed adjacent to the protective material recovery unit and purifies the recovered protective material.

[0025] A double-sided electrode plate manufacturing device according to another embodiment of the present invention may include a conveying unit for conveying a belt, a first powder application unit for applying a first powder onto the conveyed belt, a first flattening unit for flattening the applied first powder, a current collector stacking unit for stacking a current collector onto the flattened first powder, a second powder application unit for applying a second powder onto the stacked current collector, a second flattening unit for flattening the applied second powder, and a pressing unit for pressing a stack of the first powder, the current collector, and the second powder.

[0026] In an embodiment of the present invention, the compression part includes a belt member, and the belt member and the belt of the conveying part are surface presses that compress a certain area of ​​the upper and lower surfaces of the laminate, and the belt member and the belt of the conveying part may be formed of the same material.

[0027] In an embodiment of the present invention, the conveying unit comprises a plurality of rollers for conveying the belt, and the plurality of rollers comprises: a first roller disposed adjacent to the first powder coating unit; a fourth roller disposed adjacent to the end of the compression unit; a second roller disposed between the first and second flattening units; and

[0028] It includes a third roller disposed between the second leveling section and the fourth roller; wherein the first and fourth rollers are disposed at a first height, and the second and third rollers may be disposed at a second height higher than the first height.

[0029] A method for manufacturing a double-sided electrode plate according to another embodiment of the present invention may include a conveying step of conveying a protective material by a belt, a first powder application step of applying a first powder onto the conveyed protective material, a first flattening step of flattening the applied first powder, a current collector stacking step of stacking a current collector onto the flattened first powder, a second powder application step of applying a second powder onto the stacked current collector, a second flattening step of flattening the applied second powder, a compression step of compressing a laminate in which the protective material, the first powder, the current collector, and the second powder are stacked, and a protective material peeling step of peeling off the protective material.

[0030] In an embodiment of the present invention, the compression unit includes a belt member, and the compression step for compressing the laminate may be a surface press step in which a certain area of ​​the upper and lower surfaces of the laminate is compressed by the belt member and the belt of the conveying unit.

[0031] A method for manufacturing a double-sided electrode plate according to another embodiment of the present invention may include a conveying step of conveying a belt, a first powder application step of applying a first powder onto the conveyed belt, a first flattening step of flattening the applied first powder, a current collector stacking step of stacking a current collector onto the flattened first powder, a second powder application step of applying a second powder onto the stacked current collector, a second flattening step of flattening the applied second powder, and a compression step of compressing a laminate in which the first powder, the current collector, and the second powder are stacked.

[0032] In an embodiment of the present invention, the compression part includes a belt member, and the belt member and the belt of the conveying part are formed of the same material, and the step of compressing the laminate may be a surface press step of compressing a certain area of ​​the upper and lower surfaces of the laminate with the belt member and the belt of the conveying part.

[0033] The present invention improves the inefficiency of existing electrode manufacturing processes and provides the effect of simultaneously improving productivity and quality by manufacturing a double-sided electrode plate through a single compression process. In the conventional method of manufacturing double-sided electrodes, the process was complex and time-consuming because each side had to be coated and compressed separately. However, the present invention achieves the effect of maximizing productivity and significantly reducing process time by realizing a uniform active material coating on both sides through a single compression process.

[0034] In addition, as process steps are simplified, equipment usage is reduced and manufacturing costs are lowered. Unlike conventional wet processes, utilizing a dry process eliminates the need for slurry preparation and drying, and also results in reduced energy consumption. Furthermore, since the dry process does not use organic solvents, it prevents the emission of volatile organic compounds (VOCs), and protective materials can be reused, enabling resource conservation and environmentally friendly production.

[0035] In this invention, active material in powder form is evenly coated on both sides of a current collector using a belt and an ultrasonic flattening device, and a high-density electrode can be formed upon final compression. This significantly improves the energy density and uniformity of the electrode, and is expected to enhance the performance and stability of the battery. In particular, ensuring uniform quality of the double-sided electrode provides significant performance improvements in high-capacity battery applications such as electric vehicles (EVs) and energy storage systems (ESS).

[0036] Consequently, the present invention provides the effect of simultaneously achieving productivity, cost reduction, quality improvement, and eco-friendliness, and can maximize the efficiency of the high-performance battery manufacturing process. This enhances the competitiveness of the battery industry and enables the implementation of a high-efficiency manufacturing process suitable for mass production.

[0037] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the composition of the invention described in the description or claims of the present invention.

[0038] FIG. 1 shows a double-sided electrode plate manufacturing apparatus utilizing a bottom protective material, which is an embodiment of the present invention.

[0039] FIG. 2 is a side view of the flattening part constituting the present invention.

[0040] FIG. 3 is a plan view of the flattening part constituting the present invention.

[0041] FIG. 4 is a diagram showing the arrangement of the flattening unit constituting the present invention.

[0042] FIG. 5 is a conceptual diagram of a laminate according to one embodiment of the present invention.

[0043] FIG. 6 shows a double-sided electrode plate manufacturing device utilizing a bottom protective belt, which is another embodiment of the present invention.

[0044] FIG. 7 is a conceptual diagram of a laminate according to another embodiment of the present invention.

[0045] FIG. 8 is a flowchart illustrating a method for manufacturing a double-sided electrode plate, which is an embodiment of the present invention.

[0046] FIG. 9 is a flowchart illustrating a method for manufacturing a double-sided electrode plate, which is another embodiment of the present invention.

[0047] The present invention will be described below with reference to the attached drawings. However, the present invention may be implemented in various different forms and is therefore not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals.

[0048] Throughout the specification, when it is stated that a part is "connected (connected, in contact, combined)" with another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other members interposed between them. Furthermore, when it is stated that a part "includes" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components.

[0049] The terms used herein are merely for describing specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0050] Embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0051] FIG. 1 shows a double-sided electrode plate manufacturing apparatus utilizing a bottom protective material, which is an embodiment of the present invention.

[0052] Referring to FIG. 1, the present invention relates to a double-sided electrode plate manufacturing device (100) that forms a laminate (S) by applying powder-type active material powders (B, D) on both sides of a current collector (C) on a protective material (A) transported by a transport unit (10), and then completes an electrode plate (E) by peeling off the protective material (A) after the laminate (S) undergoes a single compression process. Each component of the present invention includes a transport unit (10), a first / second powder application unit (20, 50), a first / second flattening unit (30, 60), a current collector lamination unit (40), a compression unit (70), a peeling unit (80), and a reuse system, and all components are organically combined to perform an efficient process. This manufacturing process aims to improve the quality and production efficiency of the electrode plate.

[0053] The first process performed in the invention is to apply an active material powder (B) using a first powder application unit (20) onto a protective material (A) conveyed by a conveying unit (10). The first powder application unit (20) may be placed on the conveying unit (10). The powder may include an active material, a conductive material, and a binder. Specifically, the powder may be produced by mixing the active material, the conductive material, and the binder, fiberizing, and grinding, but depending on the material and composition of the binder, at least one of the fiberizing process and the grinding process may be omitted. An electrode of a negative or positive electrode may be manufactured by bonding the powder to a current collector.

[0054] The active material may include a positive electrode active material. For example, the positive electrode active material may be in the form of a lithium transition metal oxide, a lithium metal iron phosphate, or a metal oxide. The positive electrode active material may include layered compounds such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiO2), compounds substituted with one or more transition metals, lithium iron oxides such as LiFe3O4, lithium manganese oxides such as LiMnO2 and LiMnO3, lithium copper oxides such as Li2CuO2, vanadium oxides such as LiV3O8, LiV3O4, and Cu2V2O7, lithium metal phosphates such as LiFePO4, LiCoPO4, LiNiPO4, and LiMnPO4, Ni-site type lithium nickel oxide, lithium manganese complex oxide, nickel-cobalt-manganese (NCM) complex oxide, lithium-nickel-cobalt-manganese-aluminum (NCMA) complex oxide, and LiMnO in which some of the Li ions are substituted with alkaline earth metal ions. However, the embodiments are not limited thereto, and any material used as a positive electrode active material in the relevant technical field may be used. Furthermore, the embodiments are not limited to positive electrode active materials, and any material used as a negative electrode active material in the relevant technical field may be used.

[0055] In addition, the binder may include a dry binder. To explain this in detail, the binder may include having a fibrillation phenomenon. For example, the binder may include a fluorine-based binder containing a fluorine component, and may include at least one of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polyvinylidene fluoride-hexafluoropropylene (PVDFHFP) copolymers.

[0056] Additionally, the conductive material may include a dry conductive material. To be more specific, the conductive material may include a metal-based or carbon-based conductive material. For example, carbon-based conductive materials may include materials such as natural graphite, artificial graphite, carbon nanotubes (CNT), carbon fiber, graphite microparticles, and carbon black. However, the conductive material of the present invention is not limited to the aforementioned metal-based or carbon-based conductive materials, and any conductive material used in the art may be used as the conductive material of the present invention.

[0057] The first powder application unit (20) includes a hopper and a discharge port, and the discharge port located at the bottom of the hopper can be formed to discharge powder in a spray manner. It includes an internal stirring device to ensure that the powder is discharged uniformly, thereby allowing for precise control of the discharge speed and amount. This first powder application unit (20) applies the lower active material powder (B) onto a protective material (A) that moves along a belt conveying unit (10) composed of a plurality of rollers (12) and an arched belt (11), and operates in precise synchronization with the conveying speed to ensure that the active material is evenly distributed.

[0058] A plurality of rollers (12) may include first to fourth rollers (12a to 12d). The first roller (12a) may be positioned adjacent to the first powder application section (20), and the fourth roller (12d) may be positioned adjacent to the end of the compression section (70). The second and third rollers (12b, 12c) may be positioned adjacent to the second leveling section (60). Specifically, the second leveling section (60) may be positioned between the second and third rollers (12b, 12c). Additionally, the second roller (12b) may be positioned between the first and second leveling sections (30, 60), and the third roller (12c) may be positioned between the second leveling section (60) and the fourth roller (12d).

[0059] The first and fourth rollers (12a, 12d) may be positioned at a first height (h1), and the second and third rollers (12b, 12c) may be positioned at a second height (h2), preferably such that the second height (h2) is higher than the first height (h1). That is, the uppermost surface of the second and third rollers (12b, 12c) may be positioned above the uppermost surface of the first and fourth rollers (12a, 12d). By configuring the rollers in this way, sagging due to weight can be prevented without using a separate protective material when applying powder through the second powder application section, and the cross-section of the belt (11) of the conveying section may have a trapezoidal shape (arched belt).

[0060] The protective material (A) is supplied to the conveying unit (10) by a protective material supply unit (not shown) installed on one side of the belt (11) and supplied to the first powder application unit (20), and a protective material recovery unit (not shown) for recovering the protective material after the process may be installed on the other side of the belt (11).

[0061] The protective material (A) may be formed from a material that prevents damage to the lower active material powder (B) and helps to form a uniform powder layer. Since the current collector may be attached to the protective material (A) if the material of the protective material (A) is the same as the material of the current collector, it is preferable that the material of the protective material (A) be different from the material of the current collector. For example, the material of the protective material (A) may include one of the transition metals. For example, the protective material (A) may include at least one of titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), silver (Ag), platinum (Pt), ruthenium (Ru), zinc (Zn), molybdenum (Mo), tantalum (Ta), tungsten (W), and alloys thereof. Additionally, the protective material (A) may be provided as a resin material. For example, the protective material (A) may include at least one of polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polypropylene (PP), polystyrene (PS), and polymethyl methacrylate (PMMA).

[0062] In the present invention, the process performed after the first powder application is a process of flattening the lower active material powder (B) applied to the first flattening part (30). FIG. 2 is a side view of the first or second flattening part constituting the present invention, FIG. 3 is a plan view of the first or second flattening part, and FIG. 4 is a layout view of the first or second flattening part.

[0063] Referring to FIGS. 2 to 4, the lower active material powder (B) applied in the first powder application unit (20) passes through the first flattening unit (30). The first flattening unit (30) evenly arranges the powder particles through ultrasonic waves emitted from a plurality of ultrasonic radiating units (31) formed in a knife shape, and prevents the powder from accumulating or clumping in small gaps. At least one ultrasonic radiating unit (31) may be provided. A plurality of ultrasonic radiating units (31) may be provided. When a plurality of ultrasonic radiating units (31) are provided, the plurality of ultrasonic radiating units (31) may be spaced apart from each other. At this time, the ultrasonic radiating units (31) may be spaced at equal intervals. For example, as shown in the drawings, it is preferable to install three ultrasonic radiating units (31) to perform three stages of flattening. At this time, the three ultrasonic radiating units (31) may be spaced apart at equal intervals. The first ultrasonic radiating unit (31a) spreads the powder widely, the second ultrasonic radiating unit (31b) smooths out irregular parts of the surface, and the last ultrasonic radiating unit (31c) arranges the powder into a state optimized for compression. The gaps through which ultrasound is emitted from each ultrasonic radiating unit (31a, 31b, 31c) are gradually reduced, and through this process, the powder layer is evenly distributed and the density is increased. The ultrasonic radiating unit (31) can be arranged in a shape inclined at a predetermined angle of inclination.

[0064] In the first leveling section (30) of the present invention, a pair of guard belts (32) are introduced on both sides of the multi-stage ultrasonic radiation section (31) to maintain a constant loading interval and area of ​​the powder and to ensure uniform quality of the electrode plate. The guard belts (32) may be arranged parallel to the conveying direction of the belt (11) on the outer side of the coating area set to guide the powder (B) outside the set loading area in a different direction. That is, the guard belts (32) may guide the powder (B) to have a set width (W). The guard belts (32) may be formed to contact the upper surface of the protective material (A) or the belt (11). To reduce the work load during voiding or leveling operations, the length (G) of the area where the guard belts (32) are arranged may be formed to be longer than the length of the first leveling section (30). Preferably, when the length from the starting point to the end point of the guard belt (31) is denoted as lt, the first leveling section (30) may be configured to be positioned in an area between 5% and 80% of the length lt from the starting point of the guard belt (31) to smoothly recover unnecessary powder while reducing the load during voids or leveling operations. Preferably, three ultrasonic radiating sections (31a, 31b, 31c) may be positioned such that the length la from the starting point of the guard belt (31) to the first ultrasonic radiating section (31a) is 5 to 15% of the length lt, the length lb from the starting point of the guard belt (31) to the second ultrasonic radiating section (31b) is 35 to 45% of the length lt, and the length lc from the starting point of the guard belt (31) to the third ultrasonic radiating section (31c) is 65 to 80% of the length lt. At this time, la, lb, and lc each represent the distance from the starting point of the guard belt (31) to the end of each of the ultrasonic radiating parts (31a, 31b, 31c) closest to the powder, for example, the distance to the radiating tip of the ultrasonic radiating part (31a, 31b, 31c).

[0065] Additionally, if D1 is defined as the distance from the starting point of the guard belt (32) to the first ultrasonic radiating part (31a), D1 may differ from D2, which is the distance from the last ultrasonic radiating part (31c) to the end point of the guard belt (31); specifically, it is preferable that D2 is greater than D1. Accordingly, unnecessary powder can be smoothly recovered while reducing the load during the flattening operation, powder particles can be evenly arranged through ultrasound, and powder can be prevented from accumulating or clumping in small gaps.

[0066] The first leveling unit (30) of the present invention may further include a recovery unit (not shown). The recovery unit may be positioned on one side of the guard belt (32). For example, the recovery unit may be positioned on an area other than the lower area of ​​the guard belt (32) facing the belt (11), such as on at least one of the side and upper areas of the guard belt (32). Residual powder guided in a different direction by the guard belt (32) during the leveling process may be collected through the recovery unit and reused. The recovery unit may include a vacuum suction device, an air blower, etc. The recovery unit can recover unnecessary residual powder collected through the leveling process and residual powder placed outside the area set by the guard belt (32), which plays an important role in minimizing powder loss and reducing production costs. The powder recovered through the recovery unit may be supplied back to the powder application unit. The powder recovered from the area of ​​the first flattening section (30) can be supplied back to the first powder coating section (20), and the powder recovered from the area of ​​the second flattening section (60), described later, can be supplied back to the second powder coating section (50), described later, for use. Additionally, the powder recovered through the recovery section can be reused in the first powder coating section (20) or the second powder coating section (50) after quality inspection in the inspection section (not shown) or purification of the powder in the purification section (not shown). After the first flattening is completed, when the applied lower active material powder (B) layer passes through the current collector stacking section (40), a current collector (C) made of aluminum or copper foil is stacked on top of it. This current collector (C) provides electrical characteristics to the electrode and facilitates the electrochemical reaction through combination with the active material powder (B).

[0067] The current collector stacking section (40) may include a preroll (41). The preroll (41) may guide the transport path of the current collector (C). The preroll (41) may be placed on the belt (11). The preroll (41) may be placed between the first flattening section (30) and the second powder application section (50). The preroll (41) may be placed on the upper surface of the belt (11) and may be spaced apart from the upper surface of the belt (11). In the current collector stacking section (40), the current collector (C) is stacked on the lower active material powder (B) layer after passing through the preroll (41) that changes its direction of movement, and the preroll (41) is spaced apart so as not to come into contact with the active material powder (B). After the current collector (C) is stacked in the current collector stacking section (40), the upper surface active material powder (D) in powder form is applied to the current collector (C) in the second powder application section (50), and the upper surface active material powder (D) is flattened in the second flattening section (60). It is preferable that the specific configuration and operation of the second powder application section (50) and the second flattening section (60) are the same as the configuration and operation of the first powder application section (20) and the first flattening section (30), respectively.

[0068] When the upper surface active material powder (D) layer is flattened in the second flattening section (60), a laminate (S) is completed with uniform upper and lower surface active material powders (B, D) coated on both sides of the current collector (C), as illustrated in FIG. 5. As shown in FIG. 5, the completed laminate (S) has a structure in which a protective material (A), a lower surface active material powder (B), a current collector (C), and an upper surface active material powder (D) are sequentially stacked starting from the lower surface.

[0069] After two applications of active material powder and flattening are completed, the laminate is moved to the compression unit (70) and compression is performed. The compression unit (70) may include a surface press that can precisely control the powder layer so as not to be disturbed during the transfer and compression process of the electrode plate and can control the temperature of the compression surface. The compression unit (70) may include a belt member (72), and the compression unit (70) may apply surface pressure using the belt member (72). The material of the belt member (72) may be provided as one of the transition metals. For example, the belt member (72) may include at least one of titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), silver (Ag), platinum (Pt), ruthenium (Ru), zinc (Zn), molybdenum (Mo), tantalum (Ta), tungsten (W), and alloys thereof. Additionally, the belt member (72) may be provided with a resin material. For example, the protective material (A) may include at least one of polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polypropylene (PP), polystyrene (PS), and polymethyl methacrylate (PMMA). The belt member (72) may be formed from a material corresponding to the protective material (A). Preferably, the belt member (72) may be formed from the same material as the protective material (A).

[0070] The compression unit (70) can apply surface pressure to the laminate (S). The belt member (72) included in the compression unit (70) can make surface contact with the upper surface of the laminate (S). A portion of the belt (11) of the conveying unit (10), which is positioned in an area corresponding to the belt member (72) of the compression unit (70), can make surface contact with the lower surface of the laminate (S). That is, the belt member (72) and a portion of the belt (11) make surface contact with the upper and lower surfaces of the laminate (S), respectively, and can be a surface press that compresses a certain area of ​​the upper and lower surfaces of the laminate (S).

[0071] The belt member (72) may have a set width, for example, the width of the belt member (72) in the first direction (a direction perpendicular to the transport direction) may be greater than the width of the first direction of the laminate (S). Specifically, it is preferable that the width of the belt member (72) in the first direction is greater than the width of the laminate (S) in the first direction and is smaller than or equal to the width of the belt (11) of the transport unit in the first direction. In this case, when pressurizing, the belt member (72) can pressurize while wrapping around the edge region and / or side region of the laminate (S), so that an active material layer can be formed on one side and the other side of the current collector (C) with excellent uniformity characteristics after pressurization.

[0072] The compression section (70) may include a plurality of regions capable of individually controlling temperature / pressure. The compression section (70) may further include a pressurizing member (not shown). The pressurizing member may include a first pressurizing member (not shown) disposed within the belt member (72) and a second pressurizing member disposed within the belt (11) of the conveying section (10). The first pressurizing member may press the belt member (72). Specifically, the first pressurizing member may press a region of the belt member (72) in a vertical direction, for example, from the belt member (72) to the belt (11) of the conveying section (10). The second pressurizing member may press the belt (11) of the conveying section (10). Specifically, the second pressurizing member may press a region of the belt (11) in a vertical direction, for example, from the belt (11) to the belt member (72). Each of the first and second pressurizing members may include at least one of known pressurizing members capable of providing pressure to one side, such as a roll press or a surface press for pressurizing.

[0073] Additionally, the compression unit (70) may include at least one heater (not shown). For example, the compression unit (70) may include a first heater (not shown) and a second heater (not shown). The first heater may be placed within the belt member (72). The first heater may be placed in an area corresponding to the upper surface of the laminate (S). The first heater may provide thermal energy to at least one of the area of ​​the belt member (72) facing the upper surface of the laminate (S) and the first pressing member. The second heater may be placed within the belt (11) of the conveying unit (10). The second heater may be placed in an area corresponding to the lower surface of the laminate (S). The second heater may be placed between the third and fourth rollers (12c, 12d). The second heater may provide thermal energy to at least one of the area of ​​the belt (11) facing the lower surface of the laminate (S) and the second pressing member.

[0074] The temperature of the compression part (70) may gradually increase and then decrease as it moves in the conveying direction. The pressure of the compression part (70) may also gradually increase and then decrease as it moves in the conveying direction, which prevents the temperature and / or pressure from rising or falling rapidly. For example, the first pressure member may include first-1 to first-4 pressure members arranged sequentially along the conveying direction, and the second pressure member may include second-1 to second-4 pressure members arranged sequentially along the conveying direction. In this case, the pressure provided to the laminate (S) may increase as it moves from the first-1 pressure member to the first-3 pressure member, and from the second-1 pressure member to the second-3 pressure member. Additionally, the pressure provided to the laminate (S) may decrease as it moves from the first-3 pressure member to the first-4 pressure member, and from the second-3 pressure member to the second-4 pressure member.

[0075] Additionally, the pressing unit (70) may include a roll press capable of controlling the temperature of the pressing roll. The pressing unit (70) may apply different pressing conditions as needed. The surface press can control the pressing intensity through precise temperature control, and the roll press enables efficient pressing in a continuous process.

[0076] After the compression process is completed, the protective material (A) is separated from the electrode plate in the peeling section (80). The peeled protective material (A) can be recovered using a protective material recovery section (not shown), and the recovered protective material can undergo a purification process in a purification section (not shown) located adjacent to the protective material recovery section for reuse. In this process, the protective material (A) can be reused multiple times, contributing to reducing resource waste and maintaining the manufacturing process economically.

[0077] All processes of the present invention are synchronized in real time through a drive control system. The conveying speed of the belt and the working speed of each process step are controlled to match, thereby ensuring a smooth sequence of powder application, flattening, lamination, compression, and peeling processes. This system includes real-time monitoring and feedback functions, which minimize errors that may occur during the process and maintain consistent quality of the electrode plates.

[0078] As such, since the present invention does not use organic solvents through a dry coating process, there is no emission of volatile organic compounds (VOCs), and environmentally friendly production is possible. In addition, energy consumption and production costs are reduced because the drying process is eliminated.

[0079] FIG. 6 shows a double-sided electrode plate manufacturing device utilizing a bottom protective belt, which is another embodiment of the present invention.

[0080] Referring to FIG. 6, the double-sided electrode plate manufacturing device shown in this embodiment relates to a technology that forms a laminate by applying powder-shaped active material powders (B, D) on both sides of a current collector (C) on a belt (11) of a conveying unit (10) without using a protective material, and then completes the electrode plate through a single compression process.

[0081] Each component of this embodiment consists of a belt conveyor (10), first and second powder coating units (20, 50), first and second flattening units (30, 60), current collector stacking unit (40), compression unit (70), and a reuse system, and all components are organically combined to perform an efficient process. This manufacturing process aims to improve the quality and production efficiency of the electrode plate. In this embodiment, the detailed configurations of the belt conveyor (10), first and second powder coating units, first and second flattening units, current collector stacking unit (40), compression unit (70), etc., are identical to the corresponding configurations in the embodiments of FIGS. 1 to 3, so a description thereof is omitted.

[0082] The first step in the invention is to apply active material powder (B) using a first powder application unit (20) on a conveying belt (11) of a conveying unit (10). The first powder application unit (20) includes an internal stirring device to ensure that the powder (B) is discharged uniformly, and can precisely control the discharge speed and amount. This hopper applies the active material powder (B) to the lower surface of the powder on an arched belt (11) driven by a plurality of rollers (12), and operates in precise synchronization with the conveying speed to ensure that the active material is evenly distributed.

[0083] The belt (11) may be formed of a material that helps prevent damage to the lower active material powder (B) and facilitates the uniform formation of the powder layer. Since the current collector can be attached to the belt (11) if the material of the belt (11) is the same as the material of the current collector (C), it is preferable that the material of the belt (11) be different from the material of the current collector (C). For example, the material of the belt (11) may include one of the transition metals. For example, the belt (11) may include at least one of titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), silver (Ag), platinum (Pt), ruthenium (Ru), zinc (Zn), molybdenum (Mo), tantalum (Ta), tungsten (W), and alloys thereof. Additionally, the belt (11) may be provided as a resin material. For example, the belt (11) may include at least one of polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polypropylene (PP), polystyrene (PS), and polymethyl methacrylate (PMMA).

[0084] The lower active material powder (B) applied on the belt (11) is flattened by the first flattening section (30), a current collector (C) is stacked on top of it in the current collector stacking section (40), and then the upper active material powder (D) is applied on top of it in the second powder application section (50) and then flattened in the second flattening section (60) to complete the laminate (S) on the belt (11). This process is identical to the process of stacking or flattening the lower active material powder (B), the current collector (C), and the upper active material powder (D) in the embodiment of FIG. 1. As shown in FIG. 7, the completed laminate has a structure in which the lower active material powder (B), the current collector (C), and the upper active material powder (D) are sequentially stacked starting from the lower surface.

[0085] After two applications of active material powder and flattening are completed, the laminate is moved to a press device (70) and finally compressed to manufacture a double-sided electrode plate, and this process is also the same as in the embodiment of FIG. 1. However, in this embodiment, since no protective material is used on the lower surface of the laminate, the process of peeling off the protective material as in the embodiment of FIG. 1 is not required.

[0086] At this time, the belt (11) of the conveying section (10) and the belt member (72) of the compression section (70) may be provided with corresponding materials. For example, the belt (11) of the conveying section (10) and the belt member (72) of the compression section (70) may be provided with the same material among the materials described above to prevent or minimize the attachment of active material to the surface.

[0087] FIGS. 8 and FIGS. 9 are flowcharts illustrating a method for manufacturing a double-sided electrode plate according to the present invention.

[0088] Referring to FIG. 8, the method for manufacturing a double-sided electrode plate according to the present invention may include a conveying step (S1) for conveying a protective material by a belt, a first powder application step (S2) for applying a first powder on the conveyed protective material, a first flattening step (S3) for flattening the applied first powder, a current collector stacking step (S4) for stacking a current collector on the flattened first powder, a second powder application step (S5) for applying a second powder on the stacked current collector, a second flattening step (S6) for flattening the applied second powder, a compression step (S7) for compressing a laminate in which the protective material, the first powder, the current collector, and the second powder are stacked, and a protective material peeling step (S8) for peeling off the protective material. The method relates to a method for manufacturing an electrode plate using the double-sided electrode plate manufacturing device of FIG. 1, and a detailed description thereof has already been described above in the double-sided electrode plate manufacturing device of FIG. 1.

[0089] Referring to FIG. 9, the method for manufacturing a double-sided electrode plate according to the present invention may include a conveying step (S11) of conveying a protective material by a belt, a first powder application step (S12) of applying a first powder onto the conveyed protective material, a first flattening step (S13) of flattening the applied first powder, a current collector stacking step (S14) of stacking a current collector onto the flattened first powder, a second powder application step (S15) of applying a second powder onto the stacked current collector, a second flattening step (S16) of flattening the applied second powder, and a compression step (S17) of compressing a laminate in which the protective material, the first powder, the current collector, and the second powder are stacked. The method relates to a method for manufacturing an electrode plate using the double-sided electrode plate manufacturing device of FIG. 6, and a detailed description thereof has already been described above in the double-sided electrode plate manufacturing device of FIG. 6.

[0090] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0091] The scope of the present invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention.

[0092] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0093] The scope of the present invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention.

[0094] The modes for carrying out the invention are described together in the best mode for carrying out the invention above.

[0095] The present invention relates to a technology for forming a high-performance electrode by applying active material powder to both sides of a current collector using a dry coating process and compressing it, and has industrial applicability in the secondary battery industry.

Claims

1. A conveying unit that conveys protective material by belt, A first powder application unit that applies a first powder onto the conveyed protective material, A first leveling unit for leveling the applied first powder, A current collector stacking section that stacks a current collector on the flattened first powder, A second powder application unit that applies a second powder onto the stacked current collector, A second leveling unit for leveling the applied second powder, A compression part that compresses a laminate in which the above protective material, the first powder, the current collector, and the second powder are stacked, A double-sided electrode plate manufacturing apparatus comprising a protective material peeling section for peeling off the protective material.

2. In Claim 1, The above protective material is a double-sided electrode plate manufacturing device formed from one or more materials including transition metals or resins.

3. In Claim 1, The above first planarization unit is a double-sided electrode manufacturing device comprising at least one ultrasonic radiation unit.

4. In Claim 3, The above-mentioned first leveling unit is, Guard belts disposed on both sides of the ultrasonic radiation unit and controlling the loading interval of the powder; and It includes a recovery unit disposed on one side of the above guard belt, and The above recovery unit is a double-sided electrode plate manufacturing device that recovers the remaining first powder guided in another direction by the guard belt during the flattening process using the first flattening unit.

5. In Claim 4, A double-sided electrode plate manufacturing device in which, when the length from the starting point to the end point of the guard belt is defined as lt based on the conveying direction of the first powder, the first flattening part is positioned in an area between 5% and 80% of the length lt.

6. In Claim 3, The above ultrasonic radiating unit includes first to third ultrasonic radiating units spaced apart from each other along the transport direction of the first powder, and The above first to third ultrasonic radiating units are a double-sided electrode plate manufacturing device having different ultrasonic radiating gaps.

7. In Claim 1, The above conveying unit includes a plurality of rollers that convey the belt, and The above plurality of rollers are, A first roller positioned adjacent to the first powder application section; A fourth roller positioned adjacent to the end of the above-mentioned compression part; A second roller disposed between the first and second leveling sections; and A third roller disposed between the second leveling unit and the fourth roller; including The first and fourth rollers are positioned at a first height, and The above second and third rollers are a double-sided electrode plate manufacturing device positioned at a second height higher than the first height.

8. In Claim 1, The above-mentioned compression part includes a belt member, and The belt member and the belt of the conveying part are a double-sided electrode plate manufacturing device that is a surface press compressing a certain area of ​​the upper and lower surfaces of the laminate.

9. In Claim 8, The above belt member is a double-sided electrode plate manufacturing device formed from one or more materials including transition metal or resin.

10. In Claim 1, The above-mentioned compression part includes at least one heater, and A double-sided electrode plate manufacturing device in which the temperature of the above-mentioned compression section gradually increases and then decreases as it moves in the conveying direction.

11. In Claim 1, A double-sided electrode plate manufacturing device in which the pressure provided by the above-mentioned compression part to the above-mentioned laminate gradually increases and then decreases as it moves in the conveying direction.

12. In Claim 1, A protective material supply unit disposed on one side of the belt and supplying the protective material to the conveying unit; and A double-sided electrode plate manufacturing device further comprising a protective material recovery unit disposed on the other side of the above belt and recovering the protective material.

13. In Claim 12, A double-sided electrode plate manufacturing device further comprising a purification unit disposed adjacent to the protective material recovery unit and purifying the recovered protective material.

14. A conveying unit for conveying a belt, A first powder application unit that applies a first powder onto the conveyed belt, A first leveling unit for leveling the applied first powder, A current collector stacking section that stacks a current collector on the flattened first powder, A second powder application unit that applies a second powder onto the stacked current collector, A second leveling unit for leveling the applied second powder, A double-sided electrode plate manufacturing apparatus comprising a compression part for compressing a laminate in which the first powder, current collector, and second powder are laminated.

15. In Claim 14, The above-mentioned compression part includes a belt member, and The belt member and the belt of the conveying unit are surface presses that compress a certain area of ​​the upper and lower surfaces of the laminate, and A double-sided electrode plate manufacturing device in which the belt member and the belt of the conveying part are formed of the same material.

16. In Claim 14, The above conveying unit includes a plurality of rollers that convey the belt, and The above plurality of rollers are, A first roller positioned adjacent to the first powder application section; A fourth roller positioned adjacent to the end of the above-mentioned compression part; A second roller disposed between the first and second leveling sections; and A third roller disposed between the second leveling unit and the fourth roller; including The first and fourth rollers are positioned at a first height, and The above second and third rollers are a double-sided electrode plate manufacturing device positioned at a second height higher than the first height.

17. Transfer step of transporting protective material by belt, A first powder application step of applying a first powder onto the conveyed protective material, A first leveling step for leveling the applied first powder, A current collector stacking step of stacking a current collector on the flattened first powder, A second powder application step of applying a second powder onto the stacked current collector, A second flattening step for flattening the applied second powder, A compression step for compressing a laminate in which the above protective material, the first powder, the current collector, and the second powder are laminated, A method for manufacturing a double-sided electrode plate comprising a protective material peeling step for peeling off the protective material.

18. In Claim 17, The above-mentioned compression part includes a belt member, and A method for manufacturing a double-sided electrode plate, wherein the compression step for compressing the laminated body is a surface press step in which a certain area of ​​the upper and lower surfaces of the laminated body is compressed by the belt member and the belt of the conveying unit.

19. Transfer step for conveying the belt, A first powder application step of applying a first powder onto the conveyed belt, A first leveling step for leveling the applied first powder, A current collector stacking step of stacking a current collector on the flattened first powder, A second powder application step of applying a second powder onto the stacked current collector, A second flattening step for flattening the applied second powder, A method for manufacturing a double-sided electrode plate comprising a compression step of compressing a laminate in which the first powder, current collector, and second powder are laminated.

20. In Claim 19, The above-mentioned compression part includes a belt member, and The belt member and the belt of the conveying part are formed of the same material, and A method for manufacturing a double-sided electrode plate, wherein the step of compressing the laminate is a surface press step in which a certain area of ​​the upper and lower surfaces of the laminate is compressed by the belt member and the belt of the conveying unit.

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