Electrode manufacturing apparatus

Abstract

The present invention relates to an electrode manufacturing apparatus and, more particularly, to an electrode manufacturing apparatus for manufacturing an electrode for a secondary battery by a dry-process method. The electrode manufacturing apparatus according to an embodiment of the present invention comprises: a flattening unit for flattening mixture powder supplied onto the surface of a current collector by applying vibration thereto; and a main roller for pressing the flattened mixture powder and the current collector to compress the flattened mixture powder onto the current collector.

Description

Electrode manufacturing device

[0001] The present invention relates to an electrode manufacturing device, and more particularly, to an electrode manufacturing device for manufacturing an electrode of a secondary battery using a dry process method.

[0002] Secondary batteries can be manufactured through electrode processes, assembly processes, and activation processes. Through the electrode process, negative and positive electrodes are manufactured, the shape of the secondary battery is formed through the assembly process, and the electrical energy can be activated through the activation process.

[0003] The electrode process may include a mixing process, a coating process, a drying process, a roll press process, and a slitting process. Through the mixing process, the active material is produced as a slurry, through the coating process, the slurry is coated on a substrate such as aluminum or copper, through the roll press process, the slurry-coated substrate is pressed to form an electrode plate, through the drying process, the pressed electrode plate is dried, and through the slitting process, the dried electrode plate can be cut into an appropriate size.

[0004] Here, the electrode process may include a wet process and a dry process. The wet process refers to a process in which an electrode is manufactured using a liquid slurry, and the dry process refers to a process in which an electrode is manufactured using a solid powder slurry. The wet process involves a drying process, but the dry process may not involve a drying process. In other words, the production yield of electrodes can be improved by eliminating the drying process in the dry process.

[0005] Meanwhile, if the slurry is not supplied uniformly during the manufacturing of the electrode using a dry process, the quality of the electrode may deteriorate.

[0006] Therefore, there is a need for an invention that enables uniform supply of slurry in the form of solid powder.

[0007] The problem to be solved by the present invention is to provide an electrode manufacturing device for manufacturing an electrode of a secondary battery using a dry process method.

[0008] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

[0009] An electrode manufacturing device according to an embodiment of the present invention includes a flattening unit that applies vibration to a composite powder supplied to the surface of a current collector to flatten it, and a main roller that presses the flattened composite powder and the current collector to press the flattened composite powder onto the current collector.

[0010] The above-mentioned flattening unit includes a driving unit that generates a driving force, and a vibration unit that vibrates in a linear direction toward the composite powder supplied to the surface of the collector by the driving unit to flatten the composite powder.

[0011] The vibration direction of the above vibration unit is formed to be inclined at a preset angle with respect to the movement direction of the compound powder.

[0012] The above-mentioned vibrating part has a movement component in the same direction as the movement direction of the composite powder when vibrating in a direction toward the composite powder, and has a movement component in the opposite direction to the movement direction of the composite powder when vibrating in a direction away from the composite powder.

[0013] The above vibrating part includes a knife having a blade inserted into the surface of the compound powder.

[0014] The above blade has two blade surfaces extending from its tip, and the two blade surfaces are provided in a symmetrical shape.

[0015] The above two blade surfaces form a pre-set angle.

[0016] The knife is positioned at an angle with respect to the mixing powder so that the tip of the blade faces the direction of movement of the mixing powder.

[0017] The main roller includes a first main roller that presses the collector, and a second main roller that presses the flattened composite powder, and the gap between the second main roller and the collector is formed smaller than the gap between the tip of the blade and the collector.

[0018] The above composite powder includes an active material, a conductive material, and a binder mixed, fiberized, and pulverized to produce the product, and the binder includes a fluorine component.

[0019] An electrode manufacturing device according to another embodiment of the present invention includes a powder moving unit that moves a composite powder by vibration and supplies it to the upper surface of a current collector, and a main roller that presses the composite powder and the current collector to press the composite powder onto the current collector.

[0020] The above powder moving unit includes a driving unit that generates a driving force, and a sliding unit that provides a moving space for the composite powder, and slides the composite powder accommodated in the moving space by vibrating by the driving force.

[0021] The above sliding part is positioned to be inclined at a preset angle with respect to the reference plane.

[0022] The above electrode manufacturing device further includes a powder supply unit that supplies a predetermined amount of compound powder per unit time to the powder moving unit.

[0023] The above powder supply unit includes a powder receiving unit that provides a receiving space for the mixed powder and discharges the mixed powder received in the receiving space through a provided discharge port, and a powder mixing unit that rotates and mixes the mixed powder received in the receiving space.

[0024] The above discharge port includes a discharge surface parallel to the direction of movement of the mixed powder rotated by the powder mixing unit.

[0025] The above electrode manufacturing device further includes a protective film laminated on the composite powder supplied to the current collector, and the main roller presses the current collector and the protective film to press the composite powder onto the current collector.

[0026] The above electrode manufacturing device further includes an auxiliary roller that presses the current collector and the protective film to adhere the protective film to the composite powder.

[0027] A portion of the protective film entering the auxiliary roller is arranged so that the distance from the surface of the current collector increases as it moves away from the auxiliary roller in the opposite direction of entry, and the distance between the portion of the protective film having the largest distance from the surface of the current collector and the surface of the current collector is maintained at a preset distance.

[0028] The above composite powder includes an active material, a conductive material, and a binder mixed, fiberized, and pulverized to produce the product, and the binder includes a fluorine component.

[0029] Specific details of other embodiments are included in the detailed description and drawings.

[0030] According to the electrode manufacturing device according to the embodiment of the present invention as described above, there is an advantage in that the quality of the electrode is improved because the slurry in the form of solid powder is uniformly supplied.

[0031] FIG. 1 is a drawing showing an electrode manufacturing device according to an embodiment of the present invention.

[0032] Figure 2 is a drawing showing a powder moving part.

[0033] Figure 3 is a drawing showing a sliding part.

[0034] Figure 4 is a drawing showing a powder supply unit.

[0035] Figure 5 is a drawing for explaining how the composite powder is supplied to the entire body.

[0036] Figure 6 is a drawing for explaining the arrangement relationship between the powder supply unit and the powder moving unit.

[0037] Figure 7 is a drawing showing a flattened portion.

[0038] Figure 8 is a drawing showing a vibration unit.

[0039] Figure 9 is a drawing showing a knife.

[0040] Figure 10 is a drawing showing a blade.

[0041] Figure 11 is a drawing for explaining the vibration of the vibrating part.

[0042] Figure 12 is a drawing to explain the vibration of the knife.

[0043] Figure 13 is a drawing for explaining how the composite powder is pressed into the entire body.

[0044] Figure 14 is a drawing for explaining the composite powder applied to the entire body.

[0045] Figure 15 is a drawing showing a protective film entering an auxiliary roller.

[0046] Figure 16 is a flow chart showing an electrode manufacturing method.

[0047] Figures 17 to 20 are diagrams showing experimental data for examples and comparative examples.

[0048] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. The advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described in detail below together with the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

[0049] Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used in their common sense to those of ordinary skill in the art to which the present invention pertains. Furthermore, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0050] FIG. 1 is a drawing showing an electrode manufacturing device according to an embodiment of the present invention.

[0051] Referring to FIG. 1, an electrode manufacturing device (10) according to an embodiment of the present invention is configured to include a housing (100), a current collector drum (210, 220), a protective film drum (310, 320), a powder moving unit (400), a powder supply unit (500), a flattening unit (600), a flattening plate (700), a main roller (810, 820), a heating unit (831, 832), and an auxiliary roller (910, 920).

[0052] The housing (100) can accommodate a current collector drum (210, 220), a protective film drum (310, 320), a powder moving unit (400), a powder supply unit (500), a flattening unit (600), a flattening plate (700), a main roller (810, 820), a heating unit (831, 832), and an auxiliary roller (910, 920). The housing (100) can seal the inside from the outside and protect various components provided therein from external force. Meanwhile, according to some embodiments of the present invention, the electrode manufacturing device (10) may not include the housing (100). In this case, the entire body drum (210, 220), protective film drum (310, 320), powder moving unit (400), powder supply unit (500), flattening unit (600), flattening plate (700), main roller (810, 820), heating unit (831, 832), and auxiliary roller (910, 920) may be exposed to the outside.

[0053] The current collector drum (210, 220) can move the current collector (1100). The current collector drum (210, 220) can include a first current collector drum (210) and a second current collector drum (220). The first current collector drum (210) can unwind the current collector (1100), and the second current collector drum (220) can wind the current collector (1100). The current collector (1100) unwound from the first current collector drum (210) can move and be wound on the second current collector drum (220). Meanwhile, as described below, the current collector (1100) that has passed through the main roller (810, 820) can have a composite powder pressed on it. Consequently, the second current collector drum (220) can wind the current collector (1100) on which the composite powder has been pressed.

[0054] A collector guide roller (230) may be provided on the moving path of the collector (1100). The collector guide roller (230) serves to change the moving direction of the collector (1100). For example, the collector guide roller (230) may change the moving direction of the collector (1100) entering the main roller (810, 820) or may change the moving direction of the collector (1100) exiting the main roller (810, 820). Meanwhile, although FIG. 1 illustrates that two collector guide rollers (230) are provided, this is exemplary, and according to some embodiments of the present invention, three or more collector guide rollers (230) may be provided.

[0055] The protective film drum (310, 320) can move the protective film (1200). The protective film drum (310, 320) can include a first protective film drum (310) and a second protective film drum (320). The first protective film drum (310) can unwind the protective film (1200), and the second protective film drum (320) can unwind the protective film (1200). The protective film (1200) unwound from the first protective film drum (310) can be moved and wound on the second protective film drum (320).

[0056] A protective film guide roller (330) may be provided on the movement path of the protective film (1200). The protective film guide roller (330) serves to change the movement direction of the protective film (1200). For example, the protective film guide roller (330) may change the movement direction of the protective film (1200) entering the main roller (810, 820) or may change the movement direction of the protective film (1200) exiting the main roller (810, 820). Meanwhile, although FIG. 1 illustrates that two protective film guide rollers (330) are provided, this is exemplary, and according to some embodiments of the present invention, three or more protective film guide rollers (330) may be provided.

[0057] The powder moving unit (400) can move the composite powder by vibration and supply it to the surface of the current collector (1100). The electrode manufacturing device (10) according to an embodiment of the present invention can manufacture the electrode of a secondary battery using a dry process. The powder moving unit (400) can move the composite powder used in manufacturing the electrode. The composite powder may include an active material, a conductive material, and a binder. Specifically, the composite powder may be produced by mixing, fiberizing, and pulverizing the active material, the conductive material, and the binder. At this time, at least one of the fiberizing process and the pulverizing process may be omitted depending on the material and composition of the binder. An electrode, such as a negative electrode or a positive electrode, can be manufactured by binding the composite powder to the current collector (1100). The powder moving unit (400) serves to supply the composite powder used in manufacturing such an electrode to the surface of the current collector (1100). The posture and position of the powder moving part (400) can be adjusted by the user.

[0058] Here, the active material may include a cathode active material. For example, the cathode active material may be in the form of a lithium transition metal oxide, a lithium metal iron phosphate, or a metal oxide. The cathode active material may include layered compounds such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), compounds substituted with one or more transition metals, lithium iron oxide such as LiFe3O4, lithium manganese oxide such as LiMnO2, LiMnO3, lithium copper oxide such as Li2CuO2, vanadium oxide such as LiV3O8, LiV3O4, Cu2V2O7, lithium metal phosphate such as LiFePO4, LiCoPO4, LiNiPO4, LiMnPO4, Ni-site type lithium nickel oxide, lithium manganese composite oxide, nickel-cobalt-manganese (NCM) composite oxide, lithium-nickel-cobalt-manganese-aluminum (NCMA) composite oxide, LiMnO in which some of the Li ions are substituted with alkaline earth metal ions, etc. However, the examples are not limited thereto, and any material used as a cathode active material in the art may be used. In addition, the embodiment is not limited to the positive electrode active material, and any material used as a negative electrode active material in the relevant technical field can be used.

[0059] Additionally, the binder may include a dry binder. To be more specific, the binder may include a binder having a fibrillation phenomenon. For example, the binder may include a fluorine-based binder containing a fluorine component, such as at least one of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) copolymers.

[0060] Additionally, the conductive material may include a dry conductive material. More specifically, the conductive material may include a metal-based or carbon-based conductive material. For example, the carbon-based conductive material may include materials such as natural graphite, artificial graphite, carbon nanotubes (CNTs), carbon fibers, graphite particles, 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.

[0061] The powder supply unit (500) serves to supply a predetermined amount of compound powder per unit time to the powder moving unit (400). The amount of compound powder discharged from the powder supply unit (500) may be determined by the movement speed of the current collector (1100). For example, the amount of compound powder discharged from the powder supply unit (500) may be proportional to the movement speed of the current collector (1100). The powder supply unit (500) may continuously supply a uniform amount of compound powder to the powder moving unit (400), and the powder moving unit (400) may move the corresponding compound powder to the current collector (1100).

[0062] The flattening unit (600) performs the function of applying vibration to the composite powder supplied to the surface of the current collector (1100) to flatten it. The flattening unit (600) may be positioned a certain distance apart from the current collector (1100). The current collector (1100) may move in one direction. The composite powder passing through the flattening unit (600) may be distributed on the surface of the current collector (1100) with a thickness corresponding to the gap between the current collector (1100) and the flattening unit (600). At this time, the flattening unit (600) may apply vibration to the surface of the composite powder. Accordingly, the surface of the composite powder may be flattened more uniformly, and the thickness of the composite powder applied to the current collector (1100) may be formed uniformly.

[0063] The flattening plate (700) can support the current collector (1100). The flattening unit (600) can apply vibration to the composite powder applied to the surface of the current collector (1100) supported by the flattening plate (700) among the moving current collectors (1100). As the current collector (1100) is supported by the flattening plate (700), vibration of the current collector (1100) caused by the vibration of the flattening unit (600) is prevented, and the vibration of the flattening unit (600) can be concentrated on the composite powder.

[0064] The main rollers (810, 820) press the composite powder flattened by the flattening unit (600) and the current collector (1100) to press the flattened composite powder onto the current collector (1100). As the composite powder is pressed onto the current collector (1100) by the main rollers (810, 820), an electrode can be formed.

[0065] The main rollers (810, 820) may include a first main roller (810) and a second main roller (820). The first main roller (810) may pressurize the collector (1100), and the second main roller (820) may pressurize the flattened composite powder.

[0066] An electrode manufacturing device (10) according to an embodiment of the present invention may include only a pair of main rollers (810, 820). Since the composite powder entering the main rollers (810, 820) has been flattened in advance by the flattening unit (600), it can be applied to the current collector (1100) with a uniform thickness only by pressing by the pair of main rollers (810, 820). In addition, since the electrode is completed by the current collector (1100) and the composite powder passing through the pair of main rollers (810, 820), the electrode manufacturing time may be shortened.

[0067] The heating unit (831, 832) can heat the main roller (810, 820). For example, the heating unit (831, 832) can heat the main roller (810, 820) to a temperature of 100 degrees. The main roller (810, 820) can press the current collector (1100) and the composite powder while in a heated state. As the current collector (1100) and the composite powder are pressed at a relatively high temperature, the bonding force between the current collector (1100) and the composite powder can be further improved. The heating unit (831, 832) can include a first heating unit (831) and a second heating unit (832). The first heating unit (831) can heat the first main roller (810), and the second heating unit (832) can heat the second main roller (820).

[0068] Meanwhile, although FIG. 1 illustrates that the electrode manufacturing device (10) includes a first heating unit (831) and a second heating unit (832), this is merely exemplary, and according to some embodiments of the present invention, the electrode manufacturing device (10) may include only one of the first heating unit (831) and the second heating unit (832). In addition, although FIG. 1 illustrates that the first heating unit (831) is arranged at the bottom of the first main roller (810) and the second heating unit (832) is arranged at the top of the second main roller (820), this is merely exemplary, and according to some embodiments of the present invention, the heating units (831, 832) corresponding to the first main roller (810) and the second main roller (820), respectively, may be arranged inside the first main roller (810) and the second main roller (820). In addition, although FIG. 1 illustrates that only the main rollers (810, 820) are provided with heating units (831, 832), this is exemplary, and according to some embodiments of the present invention, the auxiliary rollers (910, 920) may also be provided with heating units (not shown). In this case, the pressing efficiency may be further improved as the collector (1100) and the composite powder are pressed while being heated by the auxiliary rollers (910, 920) and the main rollers (810, 820). Here, the heating units of the auxiliary rollers (910, 920) may heat the auxiliary rollers (910, 920) to a temperature lower than the temperatures of the first heating unit (831) and the second heating unit (832). That is, the heating unit of the auxiliary roller (910, 920) preheats the collector (1100) and the composite powder entering the main roller (810, 820), thereby preventing thermal deformation of the collector (1100) and the composite powder due to rapid temperature changes.

[0069] The aforementioned protective film (1200) can be laminated on the composite powder supplied to the current collector (1100). The main rollers (810, 820) can press the current collector (1100) and the protective film (1200) to compress the composite powder onto the current collector (1100). Specifically, the first main roller (810) can press the current collector (1100), and the second main roller (820) can press the protective film (1200). In this case, the second main roller (820) can press the composite powder through the protective film (1200) without directly contacting the composite powder. Since the protective film (1200) is provided between the second main roller (820) and the composite powder, the composite powder can be prevented from adhering to the second main roller (820). In addition, since the composite powder is pressurized through the protective film (1200), uniform pressure is transmitted across the entire area of ​​the composite powder, and thus the density and thickness of the composite powder can be formed uniformly.

[0070] After the compression of the composite powder by the main roller (810, 820) is performed, the protective film (1200) can be removed from the composite powder. At this time, in order to prevent the composite powder from adhering to the protective film (1200), the material of the protective film (1200) may be such that the bonding with the current collector (1100) and the composite powder is limited. The material of the current collector (1100) may be aluminum (Al) or copper (Cu). Since the protective film (1200) can be attached to the current collector (1100) when the material of the protective film (1200) is the same as the material of the current collector (1100), the material of the protective film (1200) may be different from the material of the current collector (1100). For example, the material of the protective film (1200) may include one of the transition metals. For example, the protective film (1200) 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. In addition, the protective film (1200) may be provided as a resin material. For example, the protective film (1200) may include at least one of polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polypropylene (PP), polystyrene (PS), and polymethyl methacrylate (PMMA).

[0071] The auxiliary rollers (910, 920) can control the thickness of the composite powder (1300) placed on the current collector (1100). In addition, the auxiliary rollers (910, 920) pressurize the current collector (1100) and the protective film (1200) to adhere the protective film (1200) to the composite powder. The auxiliary rollers (910, 920) may include a first auxiliary roller (910) and a second auxiliary roller (920). The first auxiliary roller (910) pressurizes the current collector (1100), and the second auxiliary roller (920) pressurizes the protective film (1200). The gap between the composite powder and the protective film (1200) is eliminated by the auxiliary rollers (910, 920), thereby improving the pressing efficiency by the main rollers (810, 820).

[0072] Figure 2 is a drawing showing a powder moving part, and Figure 3 is a drawing showing a sliding part.

[0073] Referring to FIGS. 2 and 3, the powder moving unit (400) is configured to include a driving unit (410) and a sliding unit (420).

[0074] The driving unit (410) can generate driving force. Specifically, the driving unit (410) can generate driving force for vibration of the sliding unit (420). For example, the driving unit (410) can generate driving force for vibrating the sliding unit (420) at a vibration frequency of 60 to 70 Hz.

[0075] The sliding unit (420) provides a space for the mixing powder to move, and can slide the mixing powder accommodated in the moving space by vibrating under the driving force of the driving unit (410). As described below, the mixing powder discharged from the powder supply unit (500) settles on the sliding unit (420), and the mixing powder can be slid by the sliding unit (420).

[0076] The sliding part (420) may be arranged to be inclined at a preset angle (Aa) with respect to the reference plane (BS). For example, the angle (Aa) between the reference plane (BS) and the sliding part (420) may be about 30 degrees or less. To be more specific, the angle (Aa) between the reference plane (BS) and the sliding part (420) may be about 15 degrees or less. Here, the reference plane (BS) may represent the ground or sea level. Alternatively, the reference plane (BS) may represent the upper surface of the current collector (1100) arranged on the flattening plate (700). As the sliding part (420) arranged to be inclined with respect to the reference plane (BS) vibrates, the composite powder settled on the sliding part (420) may slide along the surface of the sliding part (420). In addition, as the sliding part (420) is inclined, the powder mixture discharged through the sliding part (420) can be prevented from moving in a direction opposite to the preset movement direction (right direction in FIG. 3).

[0077] Referring to FIG. 3, the sliding part (420) may include a sliding plate (421) and a guide wall (422).

[0078] The sliding plate (421) can provide a movement path for the composite powder. The composite powder can move along the sliding plate (421) after being settled on the sliding plate (421).

[0079] The guide wall (422) may be arranged to surround the edge of the sliding plate (421). The powder mixture supplied to the sliding plate (421) may be prevented from flowing out to the outside by the guide wall (422). Meanwhile, the guide wall (422) may not be provided on one edge of the sliding plate (421). The edge is a portion arranged at the lowest position with respect to the reference surface (BS) among the entire portion of the sliding plate (421), and when the sliding part (420) vibrates, the powder mixture may be discharged through the edge.

[0080] Figure 4 is a drawing showing a powder supply unit.

[0081] Referring to FIG. 4, the powder supply unit (500) is configured to include a powder receiving unit (510) and a powder mixing unit (520).

[0082] The powder receiving unit (510) provides a receiving space for the compound powder and discharges the compound powder received in the receiving space through the provided discharge port (513). The powder mixing unit (520) rotates and mixes the compound powder received in the receiving space of the powder receiving unit (510). The shape of the powder mixing unit (520) can be determined in various ways considering the properties of the compound powder. For example, a helical ribbon impeller can be used as the powder mixing unit (520). The compound powder received in the powder receiving unit (510) can be discharged from the powder receiving unit (510) after being mixed by the powder mixing unit (520).

[0083] The powder receiving portion (510) may be spaced apart from the sliding portion (420). The powder receiving portion (510) may include an outlet (513) for discharging the powder mixture. At this time, the outlet (513) may be arranged adjacent to the sliding portion (420). For example, the outlet (513) may be arranged adjacent to the sliding plate (421) and may be arranged below the uppermost portion of the guide walls (422) arranged on both sides. Accordingly, the powder mixture discharged from the outlet (513) may be prevented from leaking to the outside by the guide walls (422).

[0084] The powder receiving portion (510) may include a guide plate (511, 512). The guide plate (511, 512) may be formed on the lower surface of the powder receiving portion (510). The guide plate (511, 512) may guide the mixed powder rotating in the powder receiving portion (510) or guide the mixed powder discharged from the powder receiving portion (510).

[0085] The guide plates (511, 512) may include a first guide plate (511) and a second guide plate (512). The first guide plate (511) and the second guide plate (512) may be arranged to be spaced apart from each other, and an outlet (513) may be formed between the first guide plate (511) and the second guide plate (512).

[0086] The discharge port (513) may have a linear shape. For example, the discharge port (513) may be provided in a linear shape extending in a direction perpendicular to the direction of movement of the compound powder. The compound powder may be discharged in a linear shape through the discharge port (513).

[0087] The first guide plate (511) and the second guide plate (512) may each include an inner surface. To describe this in detail, the first guide plate (511) may include a first inner surface (511a) facing the powder mixing unit (520), and the second guide plate (512) may include a second inner surface (512a) facing the powder mixing unit (520). The first inner surface (511a) and the second inner surface (512a) may include at least one of a flat surface and a curved surface. In addition, when the first inner surface (511a) and the second inner surface (512a) include a curved surface, the curved surface may include one curvature or a plurality of different curvatures. For example, in order to easily discharge the mixed powder, the first inner surface (511a) may be formed as a flat surface, and the second inner surface (512a) may be provided as a curved surface. The powder mixing unit (520) rotates in a circular shape, and the direction of movement of the mixed powder may represent the tangential direction of the circular trajectory by the powder mixing unit (520).

[0088] The first inner side surface (511a) may be formed in a direction inclined with respect to a direction perpendicular to the bottom surface of the powder receiving portion (510). For example, the inclination angle (Ab) of the first inner side surface (511a) with respect to the upper surface of the sliding portion (420) arranged to be inclined at a certain angle may be about 30 degrees or less. Preferably, the inclination angle (Ab) of the first inner side surface (511a) with respect to the upper surface of the sliding portion (420) may be about 5 degrees to about 25 degrees to facilitate discharge of the powder mixture.

[0089] In addition, the first guide plate (511) and the second guide plate (512) may be arranged at different heights. For example, the first guide plate (511) may be arranged below the second guide plate (512). To explain this in detail, the end of the first guide plate (511) may be arranged closer to the sliding part (420) than the end of the second guide plate (512). As illustrated in FIG. 4, in order to facilitate the discharge of the mixed powder to the discharge port (513) when the powder mixing part (520) rotates clockwise, the end of the first guide plate (511) may be arranged below the end of the second guide plate (512), and the first inner side surface (511a) of the first guide plate (511) may be provided with the aforementioned inclination angle (Ab). As the first inner side (511a) corresponding to the rotation direction of the composite powder is formed, discharge of the composite powder through the discharge port (513) can be performed more easily.

[0090] A coating layer may be formed on the inner surface of the powder receiving portion (510) and the surface of the powder mixing portion (520). The coating layer may prevent the mixed powder from adhering to the inner surface of the powder receiving portion (510) and the powder mixing portion (520). For example, the material of the coating layer may include one of the transition metals. For example, the coating layer 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. For example, the material of the coating layer may include titanium, but the material of the coating layer of the present invention is not limited to titanium.

[0091] Fig. 5 is a drawing for explaining the supply of the composite powder to the entire body, and Fig. 6 is a drawing for explaining the arrangement relationship between the powder supply unit and the powder moving unit.

[0092] Referring to FIG. 5, the composite powder (1300) can be supplied to the collector (1100) by the powder moving unit (400).

[0093] The compound powder (1300) discharged through the discharge port of the powder supply unit (500) is moved by the powder moving unit (400) and can be discharged from the end of the powder moving unit (400) and applied to the current collector (1100). The compound powder (1300) supplied to the powder moving unit (400) can be moved along the sliding unit (420) that vibrates by the driving unit (410) and can be discharged from the end of the sliding unit (420).

[0094] Referring to FIG. 6, a certain distance (D) may be formed between the discharge port (513) of the powder supply unit (500) and the end of the powder moving unit (400). Here, the end of the powder moving unit (400) may represent the edge of the sliding plate (421) on which the guide wall (422) is not formed.

[0095] The distance (D) between the discharge port (513) and the end of the powder moving unit (400) can be determined by referring to at least one of the amount of powder mixture (1300) discharged per unit time through the discharge port (513), the vibration intensity of the powder moving unit (400), the vibration frequency of the powder moving unit (400), the angle between the powder moving unit (400) and the ground, and the cohesion of the powder mixture (1300).

[0096] For example, when the edge of the sliding plate (421) on which the guide wall (422) is not formed is set as the starting point (Ps), the opposite edge of the sliding plate (421) is set as the end point (Pe), and the distance between the starting point (Ps) and the end point (Pe) is defined as 100, the discharge port (513) can be placed at a point corresponding to the distance D from the starting point (Ps) of the sliding plate (421). To explain this in detail, the distance (D) between the discharge port (513) and the end of the powder moving part (400), that is, the distance (D) between the discharge port (513) and the starting point (Ps) can satisfy a range of about 30 to about 70.

[0097] Here, when the distance (D) is less than 30, relatively strong vibration characteristics, such as vibration intensity and vibration frequency, may be required, and in this case, agglomeration of the composite powder may occur on the powder moving unit (400) due to the strong vibration. In addition, when the distance (D) is less than 30, the composite powder may be supplied unevenly onto the current collector (1100) through the end of the powder moving unit (400). For example, the amount of the composite powder provided to the central region and the edge region of the current collector (1100) may be different from each other.

[0098] In addition, when the distance (D) exceeds 70, the total movement distance of the composite powder on the powder moving unit (400) may increase. Accordingly, a clumping phenomenon of the composite powder may occur during the process of moving the composite powder by the applied vibration, and the increase in the movement distance of the composite powder may cause an increase in the total process time and a decrease in process efficiency.

[0099] Therefore, it is preferable that the distance (D) between the discharge port (513) and the end of the powder moving part (400) satisfies the above-described range to prevent and / or minimize agglomeration of the composite powder and to uniformly provide the composite powder onto the collector (1100).

[0100] The composite powder (1300) discharged from the powder moving unit (400) may be applied to the current collector (1100) and flattened by the flattening unit (600). If the composite powder (1300) applied to the current collector (1100) is unevenly distributed, flattening by the flattening unit (600) may not be performed normally. For example, flattening may be performed normally for a portion where the composite powder (1300) is distributed in a sufficiently large amount, but flattening may not be performed normally for a portion where the composite powder (1300) is distributed in an insufficient amount. Therefore, it is preferable that the composite powder (1300) be uniformly discharged from the powder moving unit (400).

[0101] The composite powder (1300) can be moved by the vibration of the powder moving unit (400) and discharged from the powder moving unit (400). The composite powder (1300) supplied from the powder supply unit (500) to the powder moving unit (400) may have an uneven density. For example, some of the composite powder (1300) supplied to the powder moving unit (400) may be in close contact with the powder particles and have a high density, while other parts may be separated from the powder particles and have a low density. The vibration of the powder moving unit (400) releases the bonds between the powder particles, and as a result, the powder moving unit (400) can discharge a uniform composite powder (1300).

[0102] Meanwhile, if the distance (D) between the outlet (513) of the powder supply unit (500) and the end of the powder moving unit (400) is too close, for example, if the distance (D) between the outlet (513) of the powder supply unit (500) and the end of the powder moving unit (400) is less than 30, the bonding between the powder particles may not be sufficiently released. Alternatively, if the distance (D) between the outlet (513) of the powder supply unit (500) and the end of the powder moving unit (400) is too far, for example, if the distance (D) between the outlet (513) of the powder supply unit (500) and the end of the powder moving unit (400) exceeds 70, coagulation may occur between the powder particles moving on the surface of the sliding unit (420).

[0103] Accordingly, the distance (D) between the discharge port (513) of the powder supply unit (500) and the end of the powder moving unit (400) can be appropriately determined with reference to the above-described criteria in order to form the density of the compound powder (1300) discharged from the powder moving unit (400) as uniform as possible.

[0104] Figure 7 is a drawing showing a flattened portion.

[0105] Referring to Fig. 7, the flattening unit (600) is configured to include a driving unit (610) and a vibrating unit (620).

[0106] The driving unit (610) can generate a driving force. Specifically, the driving unit (610) can generate a driving force for the vibration of the vibrating unit (620). For example, the driving unit (610) can generate a driving force for vibrating the vibrating unit (620) at a vibration frequency within a range of 10 to 40 kHz, and specifically, can generate a driving force for vibrating the vibrating unit (620) at a vibration frequency within an ultrasonic band. For example, the driving unit (610) can generate a driving force for vibrating the vibrating unit (620) at a vibration frequency of 20 kHz. The vibration frequency of the driving unit (610) can be determined in various ways, taking into consideration the properties of the composite powder (1300).

[0107] The vibrating unit (620) can be vibrated by the driving unit (610) to flatten the composite powder (1300). Specifically, the vibrating unit (620) can be vibrated in a linear direction toward the composite powder (1300) supplied to the surface of the current collector (1100) by the driving unit (610) to flatten the composite powder (1300). That is, the vibrating unit (620) can fill the gap formed in the composite powder (1300) by the driving unit (610), and through this process, the surface of the composite powder (1300) can be flattened. As described above, the current collector (1100) can move in one direction. In addition, the vibrating unit (620) can be vibrated in a linear direction toward the composite powder (1300). The composite powder (1300) applied to the surface of the collector (1100) moves together with the collector (1100) and comes into contact with the vibrating part (620), and the thickness of the composite powder (1300) passing through the vibrating part (620) can be formed uniformly.

[0108] Fig. 8 is a drawing showing a vibrating part, Fig. 9 is a drawing showing a knife, and Fig. 10 is a drawing showing a blade.

[0109] Referring to FIG. 8, the vibrating part (620) is configured to include a vibrating body (621), a knife (622), and a weight (623).

[0110] The vibrating body (621) can receive driving force from the driving unit (610). Although Fig. 8 illustrates a vibrating body (621) provided in the form of a bar, the shape of the vibrating body (621) of the present invention is not limited to the form of a bar. Hereinafter, the description will be focused on the case where the vibrating body (621) is provided in the form of a bar.

[0111] A knife (622) may be provided at one end of the vibrating body (621). The knife (622) may directly contact the mixture powder (1300) to evenly flatten the surface of the mixture powder (1300). The knife (622) may be provided with a blade (624) that is inserted into the surface of the mixture powder (1300). When the vibration unit (620) vibrates by the driving force of the driving unit (610), the blade (624) may be inserted into or removed from the surface of the mixture powder (1300) that moves together with the current collector (1100).

[0112] A weight (623) may be provided at the other end of the vibrating body (621) where the knife (622) is not provided. The weight (623) serves to prevent the center of gravity of the vibrating unit (620) from being concentrated on one side. If the weight (623) is not provided, the center of gravity of the vibrating unit (620) may be concentrated toward the knife (622). For example, the center of gravity of the vibrating unit (620) may be included in the knife (622). In this case, stable vibration of the vibrating unit (620) may not be performed. The center of gravity of the vibrating unit (620) may be included in the vibrating body (621) by the weight (623). The driving force of the driving unit (610) may be transmitted to the center of gravity of the vibrating unit (620). Accordingly, stable vibration of the vibrating unit (620) may be performed.

[0113] Referring to FIGS. 9 and 10, the knife (622) may have a blade (624).

[0114] The blade (624) may have two blade surfaces (624a, 624b) extending from its tip. Here, the two blade surfaces (624a, 624b) may be provided in a symmetrical shape. Referring to FIG. 9, the two blade surfaces (624a, 624b) formed above and below the reference line (BL) may have the same shape in opposite directions. Specifically, the upper and lower portions of the knife (622) formed above and below the reference line (BL) may have the same shape in opposite directions. If the upper and lower portions of the knife (622) have different shapes, stable vibration may not be performed. If the upper and lower portions of the knife (622) have different shapes, stable linear movement may not be performed, and vibration in other directions may occur. The two blade surfaces (624a, 624b) provided in the knife (622) of the present invention are provided in a symmetrical shape, and the upper and lower portions of the knife (622) may have the same shape. As a result, stable linear vibration of the knife (622) can be performed.

[0115] Referring to FIG. 10, two blade surfaces (624a, 624b) provided on the knife (622) can form a preset angle (Ac).

[0116] The angle (Ac) between the two blade surfaces (624a, 624b) may exceed 0 degrees. Accordingly, a sharp tip is formed at the end of the blade (624), and the tip of the blade (624) can be inserted into the composite powder (1300).

[0117] Fig. 11 is a drawing for explaining the vibration of the vibrating part, and Fig. 12 is a drawing for explaining the vibration of the knife.

[0118] Referring to FIG. 11, the vibrating unit (620) can vibrate in a straight direction toward the compound powder (1300) by the driving force of the driving unit (610).

[0119] The vibration direction of the vibrating unit (620) may be formed to be inclined by a preset angle (Ad) with respect to the movement direction of the composite powder (1300). For example, the angle (Ad) between the vibration direction of the vibrating unit (620) and the movement direction of the composite powder (1300) may be within a range of 10 to 20 degrees. That is, since the vibrating unit (620) is arranged to be inclined in a range of about 10 to 20 degrees with respect to the upper surface of the current collector (1100), the inclination angle between the current collector (1100) and the vibrating unit (620) may correspond to the angle (Ad), and the inclination angle between the current collector (1100) and the vibrating unit (620) may be variously determined by the user.

[0120] The vibrating unit (620) may have a movement component in the same direction as the movement direction of the composite powder (1300) when vibrating in a direction toward the composite powder (1300). Referring to FIG. 11, the vibrating unit (620) vibrating in a direction toward the composite powder (1300) may have a movement component in the right direction, which is the movement direction of the composite powder (1300). In addition, the vibrating unit (620) may have a movement component in the opposite direction to the movement direction of the composite powder (1300) when vibrating in a direction away from the composite powder (1300). Referring to FIG. 11, the vibrating unit (620) vibrating in a direction away from the composite powder (1300) may have a movement component in the left direction, which is the opposite direction to the movement direction of the composite powder (1300). The movement speed of the vibrating unit (620) may be formed to be greater than the movement speed of the composite powder (1300). Accordingly, the vibrating part (620) moving toward the composite powder (1300) can strengthen the density of the surface of the composite powder (1300) by pushing a part of the composite powder (1300).

[0121] The vibrating part (620) may be arranged at an angle with respect to the upper surface of the current collector (1100). To explain this in detail, the knife (622) may be arranged at an angle with respect to the upper surface of the current collector (1100). Accordingly, the vertical distance (based on FIG. 11) between the vibrating part (620) and the current collector (1100) may become closer as the current collector (1100) and the composite powder (1300) move in the moving direction (rightward in FIG. 11). To explain this in detail, the vertical distance (based on FIG. 11) between the knife (622) and the current collector (1100) may become closer as the current collector (1100) and the composite powder (1300) move in the moving direction (rightward in FIG. 11). To explain this in more detail, the vertical distance (based on FIG. 11) between the blade surfaces (624a, 624b) and the current collector (1100) may become closer as the movement direction of the current collector (1100) and the composite powder (1300) progresses (to the right in FIG. 11). That is, the vibrating part (620) may be arranged to be inclined in the range of about 10 to 20 degrees with respect to the upper surface of the current collector (1100). To explain this in more detail, the knife (622) may be arranged to be inclined in the range of about 10 to 20 degrees with respect to the upper surface of the current collector (1100). The angle of inclination between the knife (622) and the current collector (1100) may correspond to the angle (Ad) described above.

[0122] The knife (622) may be positioned so that the tip of the blade (624) is inclined with respect to the composite powder (1300) so that the tip of the blade (624) faces the moving direction of the composite powder (1300). The gap between the collector (1100) and the tip of the blade (624) may be determined to be a preset distance, and the gap may be variously determined by adjusting the position of the vibrating unit (620). The thickness of the composite powder (1300) passing through the knife (622) may be formed similar to the gap between the collector (1100) and the tip of the blade (624). For example, the vertical gap (based on FIG. 11) between the collector (1100) and the tip of the blade (624) may be a first gap described below, which may be about 100% to about 300% of the target electrode thickness. Here, the target electrode thickness may refer to the thickness of the electrode manufactured by passing through the main roller (810, 820), and may refer to the thickness of the electrode to be finally manufactured through the electrode manufacturing device (10). To explain in detail, the target electrode thickness refers to the thickness of the electrode layer formed by the composite powder (1300) applied to the upper surface of the current collector (1100), and may refer to the vertical thickness from the upper surface of the current collector (1100) to the uppermost surface of the electrode layer.

[0123] Referring to FIG. 12, the knife (622) can vibrate with a certain amplitude (D).

[0124] The vibrating unit (620) can vibrate at an angle (Ad) set in advance with respect to the direction of movement of the composite powder (1300). In this case, the amplitude (D) of the knife (622) can include a vertical amplitude component (Dy). Here, the vertical direction may represent a vertical direction with respect to the surface of the current collector (1100). That is, the knife (622) repeats movement toward the current collector (1100) and movement away from the current collector (1100). Hereinafter, the vertical amplitude component (Dy) is referred to as vertical amplitude (Dy).

[0125] The thickness of the composite powder (1300) that has passed through the flattening section (600) may correspond to the distance between the tip of the blade (624) and the collector (1100) when the knife (622) has been retracted to the maximum. When the knife (622) has been advanced to the maximum, the blade (624) of the knife (622) may be inserted into the composite powder (1300). Through this process, a fine groove having a depth corresponding to the vertical amplitude (Dy) of the knife (622) may be formed on the surface of the composite powder (1300) that has passed through the flattening section (600). The vertical amplitude (Dy) of the knife (622) may satisfy the thickness of the composite powder (1300) that has passed through the main rollers (810, 820), which is 30% or less of the target electrode thickness. To elaborate, the vertical amplitude (Dy) of the knife (622) can be within a range of 0.01% to 5% of the target electrode thickness.

[0126] When the vertical amplitude (Dy) is less than about 0.01% of the target electrode thickness, the flattening effect may be minimal. When the vertical amplitude (Dy) is more than about 5% of the target electrode thickness, the flattening effect may be sufficiently provided, but the vibration may be too strong, causing the edge area of ​​the composite powder (1300) applied to the current collector (1100) to be irregularly deformed, and the composite powder (1300) to splash on the surface of the composite powder (1300), which may lower the reliability of the manufactured electrode. Therefore, considering the manufacturing uniformity of the edge area of ​​the composite powder (1300) and the reliability of the manufactured electrode, it is preferable that the vertical amplitude (Dy) satisfies the above-mentioned range.

[0127] The shape of the tip of the blade (624) can be determined in various ways, taking into consideration the properties of the composite powder (1300). For example, the shape of the tip of the blade (624) can be straight or wrinkled. The knife (622) can be detachably attached to the vibrating body (621). By replacing the knife (622), flattening can be performed using the blade (624) equipped with tips of various shapes.

[0128] The material of the blade (624) can be determined in various ways considering the properties of the composite powder (1300). The material of the blade (624) may be such that the combination with the composite powder (1300) is limited. For example, the material of the blade (624) may include a transition metal. For example, the material of the blade (624) 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. For example, the material of the blade (624) may be titanium, but the material of the blade (624) of the present invention is not limited to titanium. Flattening can be performed using blades (624) of various materials by replacing the knife (622).

[0129] Fig. 13 is a drawing for explaining the pressing of the composite powder onto the entire body, Fig. 14 is a drawing for explaining the composite powder applied to the entire body, and Fig. 15 is a drawing showing a protective film entering an auxiliary roller.

[0130] Referring to FIG. 13, the main roller (810, 820) can pressurize the collector (1100) and the protective film (1200) to cause the composite powder (1300) to be pressed onto the collector (1100).

[0131] The collector (1100), the composite powder (1300), and the protective film (1200) enter the main roller (810, 820) as an integrated unit, and the main roller (810, 820) can pressurize the integrated collector (1100), the composite powder (1300), and the protective film (1200).

[0132] The first main roller (810) can pressurize the collector (1100), and the second main roller (820) can pressurize the protective film (1200). The composite powder (1300) is pressed onto the collector (1100) by the main rollers (810, 820), and then the protective film (1200) can be separated from the composite powder (1300).

[0133] The gap between the second main roller (820) and the current collector (1100) (based on the vertical direction in FIG. 13) can be formed smaller than the gap between the tip of the blade (624) and the current collector (1100) described above (based on the vertical direction in FIG. 11). Here, the gap between the tip of the blade (624) and the current collector (1100) can form the thickness of the flattened composite powder (1300), and the gap between the second main roller (820) and the current collector (1100) can form the thickness of the composite powder (1300) pressed onto the current collector (1100). As a result, the flattened composite powder (1300) can be formed on the current collector (1100) with a preset thickness, i.e., a target electrode thickness, after being pressed by the main rollers (810, 820) and passing through the main rollers (810, 820).

[0134] At this time, when the gap between the tip of the blade (624) and the collector (1100) in the vertical direction is defined as the first gap, and the gap between the second main roller (820) and the collector (1100) is defined as the second gap, the second gap may be smaller than the first gap.

[0135] For example, the first gap may be about 100% to about 300% of the target electrode thickness. If the first gap is less than 100% of the target electrode thickness, it may be difficult for the thickness of the electrode layer formed by passing through the main rollers (810, 820) to satisfy the target electrode thickness, and if it exceeds 300%, it may be difficult to control the target electrode thickness, and a load may be applied to each roller (810, 820, 910, 920) during the process in which the composite powder (1300) passes through the auxiliary rollers (910, 920) and the main rollers (810, 820).

[0136] In addition, the second gap may be about 65% to about 95% of the target electrode thickness. If the second gap is less than 65% of the target electrode thickness, excessively large pressure may be applied to the composite powder (1300) passing through the main roller (810, 820). The thickness of the electrode layer formed through this process may be thinner than the target electrode thickness, and cracks, etc. may occur on the surface of the electrode layer due to the relatively large pressure. In addition, if the second gap exceeds 95% of the target electrode thickness, the thickness of the formed electrode layer may be thicker than the target electrode thickness. In addition, the ratio of internal voids in the electrode layer formed through this process is formed largely, which may lower the efficiency of the electrode and reduce the overall capacity of the battery including the electrode.

[0137] Auxiliary rollers (910, 920) may be provided adjacent to the main rollers (810, 820). The auxiliary rollers (910, 920) may perform pre-pressurization on the current collector (1100), the composite powder (1300), and the protective film (1200) entering the main roller (810, 820). The current collector (1100), the composite powder (1300), and the protective film (1200) may be preferentially pressurized by the auxiliary rollers (910, 920) before entering the main roller (810, 820).

[0138] The composite powder (1300) entering the auxiliary roller (910, 920) may have been completely flattened by the flattening unit (600). The protective film (1200) prior to passing through the auxiliary roller (910, 920) is not in close contact with the composite powder (1300), and may be pressed by the auxiliary roller (910, 920) to be in close contact with the composite powder (1300).

[0139] To explain this in detail, the current collector (1100) may be in contact with the first auxiliary roller (910), and the second auxiliary roller (920) may be in contact with the protective film (1200). The auxiliary rollers (910, 920) may pre-pressurize the current collector (1100), the composite powder (1300), and the protective film (1200) entering the main rollers (810, 820), or guide the protective film (1200) to the composite powder (1300). Here, when the protective film (1200) is guided to the composite powder (1300), the auxiliary rollers (910, 920), i.e., the second auxiliary roller (920), may not pressurize the composite powder (1300).

[0140] At this time, the gap between the second auxiliary roller (920) and the collector (1100) in the vertical direction can be defined as a third gap. The third gap can be smaller or larger than the first gap. Additionally, the third gap can be larger than the second gap.

[0141] For example, the third gap may be about 90% to about 1000% of the target electrode thickness. If the third gap is less than 90% of the target electrode thickness, a relatively large pressure may be applied to the composite powder (1300) before passing through the main roller (810, 820). As a result, the composite powder (1300) enters the main roller (810, 820) with a thickness thinner than a preset thickness, and thus, the thickness of the electrode layer finally formed on the current collector (1100) may be thinner than the target electrode thickness. In addition, when the third gap exceeds about 1000% of the target electrode thickness, the second auxiliary roller (920) can appropriately guide the protective film (1200) to the composite powder (1300), but the inclination angle at which the protective film (1200) is provided in the area between the auxiliary rollers (910, 920) and the main rollers (810, 820) may be formed too large. Accordingly, the alignment characteristics of the protective film (1200) and the composite powder (1300) in the arrangement area of ​​the main rollers (810, 820) may deteriorate. In particular, in the above case, a part of the composite powder (1300) may detach from the current collector (1100) to the second main roller (820), which may cause a reliability problem of the electrode layer formed, and a problem of a shortened maintenance cycle for the main rollers (810, 820) may also occur.

[0142] The thickness of the composite powder (1300) flattened by the flattening unit (600) may gradually decrease as it passes through the auxiliary rollers (910, 920) and the main rollers (810, 820). Referring to FIG. 13, the thickness of the composite powder (1300) may decrease as it passes through points P1, P2, and P3. Here, point P1 may mean any point in the area between the flattening unit (600) and the auxiliary rollers (910, 920). To explain this in detail, the thickness of the composite powder (1300) on the current collector (1100) may decrease as it passes through the flattening unit (600), the auxiliary rollers (910, 920), and the main rollers (810, 820) having first to third intervals.

[0143] The auxiliary rollers (910, 920) only perform the role of adhering the protective film (1200) to the composite powder (1300) and may not pressurize the composite powder (1300). That is, when the second auxiliary roller (920) guides the protective film (1200) as described above, the thickness of the composite powder (1300) at point P2 may be formed to be the same as the thickness of the composite powder (1300) at point P1.

[0144] Referring to FIGS. 13 and 14, the composite powder (1300) can be pressed onto the current collector (1100) at a preset target width. That is, the width (Wp) of the composite powder (1300) at point P3 can be the target width. Here, the preset target width represents a width measured in a direction perpendicular to the movement direction of the current collector (1100) and the composite powder (1300), and may refer to the width of the target electrode described above.

[0145] If the widths of the knife (622), auxiliary rollers (910, 920), and main rollers (810, 820) are not sufficiently large, the composite powder (1300) may not be compressed normally. The width (Wf) of the knife (622) may be included in a range of 110 to 150% of the target electrode width. To explain this in detail, the width (Wf) of the blade (624) that contacts the composite powder (1300) may be included in a range of 110 to 150% of the width of the target electrode. In addition, the widths (Wm, Ws) of the auxiliary rollers (910, 920) and the main rollers (810, 820) may be larger than the width (Wf) of the blade (624) in order to pressurize and / or guide the composite powder (1300) that has passed through the flattening section (600). For example, the widths (Wm, Ws) of the auxiliary rollers (910, 920) and the main rollers (810, 820) may be within a range of 120 to 250% of the target electrode width. In addition, the widths (Wm, Ws) of the auxiliary rollers (910, 920) and the main rollers (810, 820) may be the same as or different from each other within the aforementioned range. However, when the widths of the auxiliary rollers (910, 920) and the main rollers (810, 820) are different from each other, the width (Wm) of the main rollers (810, 820) may be larger than the width (Ws) of the auxiliary rollers (910, 920) in order to remove the width and thickness of the target electrode. Referring to FIG. 15, a portion (1210) of the protective film (1200) entering the auxiliary roller (910, 920) may be arranged so that the distance between the portion (1210) and the surface of the current collector (1100) increases as the portion moves away from the auxiliary roller (910, 920) in the opposite direction of entry. That is, the portion (1210) of the protective film (1200) may form a certain angle (Ae) with respect to the direction in which the current collector advances. In addition, the distance between the portion (1210) of the protective film (1200) entering the auxiliary roller (910, 920) with the largest distance between the portion and the surface of the current collector (1100) and the surface of the current collector (1100) may be maintained at a preset distance.Hereinafter, a portion (1210) of the protective film (1200) entering the auxiliary roller (910, 920) is referred to as a guide area.

[0146] If there is no guide area (1210), a part of the composite powder (1300) may be pushed by the auxiliary rollers (910, 920) and may not adhere to the collector (1100). As the guide area (1210) is arranged on the surface of the composite powder (1300), the detachment of the composite powder (1300) by the auxiliary rollers (910, 920) can be prevented. In order to improve the effect of the guide area (1210), it is preferable that the guide area (1210) be arranged so as to adhere as closely as possible to the composite powder (1300) entering the auxiliary rollers (910, 920). For example, the distance between the part of the guide area (1210) with the largest distance from the surface of the collector (1100) and the surface of the collector (1100) may be formed to be similar to the thickness of the composite powder (1300). For this purpose, the position of the protective film guide roller (330) can be freely determined.

[0147] Figure 16 is a flowchart showing an electrode manufacturing method according to an embodiment of the present invention.

[0148] Referring to FIG. 16, the electrode manufacturing method according to the embodiment of the present invention may include a method of producing a composite powder (1300) including a mixing step (S1410), a fiberization step (S1420), a grinding step (S1430), a coating step (S1440), a flattening step (S1450), a pre-pressing step (S1460), and a main pressing step (S1470).

[0149] The mixing step (S1410) represents a step in which an active material, a conductive material, and a binder are mixed. The active material, the conductive material, and the binder may be mixed in a single space. The active material may include a lithium transition metal compound. For example, the active material may be represented by LiMO2, which is a layered lithium transition metal compound as a positive electrode active material. Here, M may include at least one of transition metals such as nickel (Ni), manganese (Mn), cobalt (Co), or aluminum (Al). 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 cathode active material may include layered compounds such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), compounds substituted with one or more transition metals, lithium iron oxide such as LiFe3O4, lithium manganese oxide such as LiMnO2, LiMnO3, lithium copper oxide such as Li2CuO2, vanadium oxide such as LiV3O8, LiV3O4, Cu2V2O7, lithium metal phosphate such as LiFePO4, LiCoPO4, LiNiPO4, LiMnPO4, Ni-site type lithium nickel oxide, lithium manganese composite oxide, nickel-cobalt-manganese (NCM) composite oxide, lithium-nickel-cobalt-manganese-aluminum (NCMA) composite oxide, LiMnO in which some of the Li ions are substituted with alkaline earth metal ions, etc. However, the examples are not limited thereto, and any material used as a cathode active material in the art may be used. In addition, the embodiment is not limited to the positive electrode active material, and any material used as a negative electrode active material in the relevant technical field can be used.

[0150] In the present invention, the binder may include a dry binder. More specifically, the binder may include a binder having a fibrillation phenomenon. For example, the binder may include a fluorine-based binder containing a fluorine component, such as at least one of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) copolymers. The binder containing a fluorine component may be mixed with the active material and the conductive material.

[0151] Additionally, the conductive material may include a dry conductive material. More specifically, the conductive material may include a metal-based or carbon-based conductive material. For example, the carbon-based conductive material may include materials such as natural graphite, artificial graphite, carbon nanotubes (CNTs), carbon fibers, graphite particles, 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.

[0152] The fiberization step (S1420) refers to the step in which the active material and conductive material are bound to each other by the fiberized binder. Through the fiberization step (S1420), a mixture in which the active material, conductive material, and binder are bound can be formed. That is, in the fiberization step (S1420), the binder can support the dry active material and other components and bind them together.

[0153] The crushing step (S1430) refers to the step in which the mixture of the active material, conductive material, and binder is converted into a powder form. The mixture can be crushed into particles using a crusher (not shown). The mixture can be crushed until it is converted into particles of a preset size.

[0154] Upon completion of the crushing step (S1430), a composite powder (1300) can be formed. The composite powder (1300) can be combined with a current collector (1100) as described above and used in the manufacture of an electrode.

[0155] Meanwhile, according to some embodiments of the present invention, the binder used in the production of the composite powder (1300) may include a non-fluorine component. In this case, the aforementioned fiberization step (S1420) and grinding step (S1430) may be omitted.

[0156] The application step (S1440) represents a step in which a composite powder (1300) is applied to the current collector (1100). The composite powder (1300) can be supplied to the surface of the current collector (1100) by being moved by the vibration of the powder moving unit (400). As the composite powder (1300) is supplied to the surface of the current collector (1100) moving to one side, the composite powder (1300) can be applied to the surface of the current collector (1100).

[0157] The flattening step (S1450) represents a step in which flattening is performed on the composite powder (1300) applied to the current collector (1100). The flattening unit (600) can flatten the composite powder (1300) by applying vibration to the surface of the composite powder (1300) applied to the current collector (1100) moving to one side. The thickness of the composite powder (1300) applied to the current collector (1100) can be formed uniformly by the flattening unit (600).

[0158] The pre-pressing step (S1460) represents a step in which a protective film (1200) is adhered to the flattened composite powder (1300). The protective film (1200) may be settled on the surface of the flattened composite powder (1300). The auxiliary rollers (910, 920) may press the current collector (1100) and the protective film (1200) so that the protective film (1200) adheres to the composite powder (1300). At this time, the composite powder (1300) may also be pressed to the current collector (1100).

[0159] The main pressing step (S1470) represents a step in which the composite powder (1300) distributed between the protective film (1200) and the current collector (1100) is pressed onto the current collector (1100). The main rollers (810, 820) can press the current collector (1100) and the protective film (1200) to press the composite powder (1300) onto the current collector (1100). The second main roller (820) can press through the protective film (1200). Since the protective film (1200) is disposed between the second main roller (820) and the composite powder (1300), the composite powder (1300) can be prevented from adhering to the second main roller (820). In addition, since the composite powder (1300) is pressurized through the protective film (1200), uniform pressure is transmitted across the entire area of ​​the composite powder (1300), and thus the density and thickness of the composite powder (1300) can be formed uniformly.

[0160] After the main pressing step (S1470), the protective film (1200) can be removed from the composite powder (1300), and an electrode including a current collector (1100) and the composite powder (1300) pressed thereto can be manufactured.

[0161] A portion of the composite powder (1300) used in the application step (S1440), the flattening step (S1450), the pre-compression step (S1460), and the main compression step (S1470) can be separated from the current collector (1100). Since a portion of the composite powder (1300) applied to the current collector (1100) can be separated, such composite powder (1300) can be collected and used in a subsequent electrode manufacturing process. Since the composite powder (1300) that is not bound to the current collector (1100) can be reused, the process yield can be improved.

[0162] Figures 17 to 20 are diagrams showing experimental data for examples and comparative examples.

[0163] FIG. 17 and FIG. 18 are experimental data showing that flattening of a composite powder (1300) was performed using a flattening unit (600) according to an embodiment, and FIG. 19 and FIG. 20 are experimental data showing that flattening of a composite powder (1300) was performed using a flattening unit (600) according to a comparative example. Hereinafter, the operation and effects of the present invention will be described in more detail through examples and comparative examples.

[0164] [Example 1]

[0165] An electrode manufacturing device was manufactured in which a composite powder (1300) was applied to an area of ​​a substrate (1500) and a flattening portion (600) was placed on the substrate (1500) and the composite powder (1300).

[0166] As illustrated in Fig. 17(a), the flattening unit (600) was arranged such that the blade (624) was inclined at an angle of 15 degrees with respect to the upper surface of the substrate (1500). To explain this in detail, the flattening unit (600) was arranged such that the vertical distance between the blade (624) and the substrate (1500) became closer as the substrate (1500) and the composite powder (1300) moved in the direction of movement. In addition, the amplitude of the blade (624) of the flattening unit (600) was set to a value corresponding to 1% of the target electrode thickness to be formed. Thereafter, as the substrate (1500) and the composite powder (1300) passed through the flattening unit (600), flattening of the composite powder (1300) was performed.

[0167] Fig. 17(b) shows a composite powder (1300) that has been flattened under the conditions of Fig. 17(a).

[0168] [Example 2]

[0169] As shown in Fig. 18(a), the amplitude of the blade (624) of the flattening section (600) was set to a value corresponding to 1.5% of the target electrode thickness to be formed, and except for this, flattening of the composite powder (1300) was performed while the substrate (1500) and the composite powder (1300) passed through the flattening section (600) under the same conditions as Example 1.

[0170] Fig. 18(b) shows a composite powder (1300) that has been flattened under the conditions of Fig. 18(a).

[0171] [Comparative Example 1]

[0172] As shown in Fig. 19(a), the amplitude of the blade (624) of the flattening section (600) was set to a value corresponding to 5% of the target electrode thickness to be formed, and except for this, flattening of the composite powder (1300) was performed while the substrate (1500) and the composite powder (1300) passed through the flattening section (600) under the same conditions as Example 1.

[0173] Fig. 19(b) shows a composite powder (1300) that has been flattened under the conditions of Fig. 15(a).

[0174] [Comparative Example 2]

[0175] As shown in Fig. 20(a), the flattening section (600) was arranged at an angle with respect to the upper surface of the substrate (1500) so that the vertical distance between the blade (624) and the substrate (1500) increased as the substrate (1500) and the composite powder (1300) moved in the same direction as the moving direction of the substrate (1500), and except for this, the substrate (1500) and the composite powder (1300) passed through the flattening section (600) under the same conditions as Example 1, and the composite powder (1300) was flattened.

[0176] Fig. 20(b) shows a composite powder (1300) that has been flattened under the conditions of Fig. 16(a).

[0177] Referring to FIGS. 17 and 18, the composite powder (1300) that passed through the flattening section (600) of the electrode manufacturing device according to Examples 1 and 2 had its surface flattened by the flattening section (600).

[0178] In addition, referring to FIGS. 17 and 18, it can be confirmed that the surface of the composite powder (1300) that has passed through the flattening section (600) is provided in a uniformly compacted form, and it can be confirmed that the phenomenon of breaking does not occur or is minimized in the edge area of ​​the composite powder (1300).

[0179] In contrast, referring to FIG. 19, it can be confirmed that the surface of the composite powder (1300) that passed through the flattening section (600) in Comparative Example 1 was flattened. However, due to the relatively large amplitude of the blade (624), a phenomenon of powder particles bouncing was observed in the process of the composite powder (1300) passing through the flattening section (600), and the shape of the edge area of ​​the composite powder (1300) became irregular due to the bouncing phenomenon.

[0180] In addition, referring to FIG. 20, in Comparative Example 2, it was observed that the composite powder (1300) was pushed by the blade (624) during the process of passing through the flattening section (600), and it was also observed that the flattening of the composite powder (1300) was irregular.

[0181] An electrode manufacturing device (10) according to an embodiment of the present invention can continuously manufacture dry electrodes using a dry mixture powder (1300). To this end, the dry mixture powder (1300) can be continuously and rapidly flattened by a flattening unit (600) having characteristics such as a set position and amplitude. Accordingly, the electrode manufacturing device (10) according to an embodiment of the present invention can have improved process efficiency.

[0182] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. A flattening unit that vibrates and flattens the compound powder supplied to the surface of the entire body; and An electrode manufacturing device including a main roller that presses the flattened composite powder and the current collector to press the flattened composite powder onto the current collector.

2. In paragraph 1, The above flattening part is, a driving unit that generates driving force; and An electrode manufacturing device including a vibrating unit that vibrates in a linear direction toward the composite powder supplied to the surface of the collector by the driving unit to flatten the composite powder.

3. In paragraph 2, An electrode manufacturing device in which the vibration direction of the above-mentioned vibration unit is formed to be inclined at a preset angle with respect to the movement direction of the compound powder.

4. In paragraph 3, The above vibration part, When vibrating in the direction toward the composite powder, it has a movement component in the same direction as the movement direction of the composite powder, An electrode manufacturing device having a moving component in the opposite direction to the moving direction of the composite powder when vibrating in the direction of separation from the composite powder.

5. In paragraph 2, The above vibrating part is an electrode manufacturing device including a knife having a blade inserted into the surface of the composite powder.

6. In paragraph 5, The above blade has two blade faces extending from its tip, An electrode manufacturing device in which the above two blade surfaces are provided in a symmetrical shape.

7. In paragraph 6, An electrode manufacturing device in which the above two blade surfaces form a preset angle.

8. In paragraph 5, An electrode manufacturing device in which the knife is positioned at an angle with respect to the composite powder so that the tip of the blade faces the direction of movement of the composite powder.

9. In paragraph 5, The above main roller, A first main roller for pressurizing the entire body; and Including a second main roller for pressing the flattened composite powder, An electrode manufacturing device in which the gap between the second main roller and the current collector is formed smaller than the gap between the tip of the blade and the current collector.

10. In paragraph 1, The above composite powder includes an active material, a conductive material, and a binder mixed, fiberized, and pulverized to produce the product. The above binder is an electrode manufacturing device containing a fluorine component.

11. A powder moving unit that moves the composite powder by vibration and supplies it to the upper surface of the collector; and An electrode manufacturing device including a main roller that pressurizes the composite powder and the current collector to press the composite powder onto the current collector.

12. In paragraph 11, The above powder moving part, a driving unit that generates driving force; and An electrode manufacturing device comprising a sliding unit that provides a space for moving a composite powder and slides the composite powder accommodated in the moving space by vibrating by the driving force.

13. In paragraph 12, An electrode manufacturing device in which the above sliding part is arranged to be inclined at a preset angle with respect to a reference plane.

14. In paragraph 11, An electrode manufacturing device further comprising a powder supply unit that supplies a predetermined amount of compound powder per unit time to the powder moving unit.

15. In paragraph 14, The above powder supply unit, A powder receiving unit that provides a receiving space for the compound powder and discharges the compound powder received in the receiving space through a discharge port provided; and An electrode manufacturing device including a powder mixing unit that mixes the composite powder accommodated in the above-mentioned accommodation space by rotating it.

16. In paragraph 15, An electrode manufacturing device wherein the above discharge port includes a discharge surface parallel to the direction of movement of the mixed powder rotated by the above powder mixing unit.

17. In paragraph 11, Further comprising a protective film laminated on the composite powder supplied to the above-mentioned collector, An electrode manufacturing device in which the main roller presses the collector and the protective film to press the composite powder onto the collector.

18. In paragraph 17, An electrode manufacturing device further comprising an auxiliary roller that presses the entire body and the protective film to adhere the protective film to the composite powder.

19. In paragraph 18, A portion of the protective film entering the auxiliary roller is arranged so that the distance from the surface of the collector increases as it moves away from the auxiliary roller in the opposite direction of entry, An electrode manufacturing device in which the gap between a portion of the protective film having the largest gap with the surface of the current collector and the surface of the current collector is maintained at a preset gap.

20. In paragraph 11, The above composite powder includes an active material, a conductive material, and a binder mixed, fiberized, and pulverized to produce the product. The above binder is an electrode manufacturing device containing a fluorine component.

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