Secondary battery manufacturing apparatus

Abstract

The present disclosure relates to an apparatus for manufacturing a secondary battery. The technical problem to be solved is to provide an apparatus for manufacturing a secondary battery capable of removing gas from a slurry to be applied to a substrate. To this end, the present disclosure provides an apparatus for manufacturing a secondary battery, the apparatus comprising: a housing part provided with a nozzle at a position facing a substrate moved by a coating roller; the cavity part is located in the shell part and forms a guide pipe used for conveying the coating solution to the nozzle; an exhaust portion, one side of which is mounted in a shape surrounding an opening of the cavity portion, and the other side of which extends to the outside of the housing portion to form a path for exhausting gas; and a filtering portion located between the cavity portion and the exhaust portion and configured to move only the gas contained in the coating solution in a direction toward the exhaust portion.

Description

Technical Field

[0001] The present disclosure relates to a secondary battery manufacturing apparatus. Background Art

[0002] Unlike primary batteries, which cannot be recharged, secondary batteries are batteries that can be charged and discharged. Low-capacity secondary batteries are used in small portable electronic devices (such as smartphones, feature phones, laptops, digital cameras, and video cameras), while large-capacity secondary batteries are widely used as power sources for driving electric motors in hybrid and electric vehicles, as well as batteries for storing electricity. These secondary batteries include an electrode assembly consisting of a positive electrode and a negative electrode, a casing that houses the electrode assembly, and terminals connected to the electrode assembly.

[0003] In the manufacture of secondary batteries, a process of uniformly applying a slurry containing an active material and the like onto a thin substrate is one of the important processes for ensuring stable performance and safety of the secondary batteries.

[0004] The above information disclosed in the background of the present disclosure is only for improving understanding of the background of the present disclosure and therefore may include information that does not constitute related art. Summary of the Invention

[0005] The present disclosure relates to a secondary battery manufacturing apparatus capable of removing gas from a slurry to be applied on a substrate.

[0006] However, the technical problems to be solved by the present disclosure are not limited to the above-mentioned technical problems, and those skilled in the art will clearly understand other technical problems not mentioned from the following description.

[0007] An exemplary secondary battery manufacturing device for solving the above technical problems according to an embodiment of the present disclosure includes: a shell portion, provided with a nozzle, which is configured to face a substrate being moved by a coating roller; a cavity portion, located within the shell portion, which forms a conduit for delivering a coating solution to the nozzle; an exhaust portion, having a first side surrounding an opening of the cavity portion and a second side extending outward from the shell portion to form a path for exhausting gas; and a filter portion, located between the cavity portion and the exhaust portion, which is configured to guide the gas contained in the coating solution in a direction toward the exhaust portion and prevent liquid of the coating solution from being guided to the exhaust portion.

[0008] In some examples, the housing portion may include a lower housing surrounding a lower portion of the cavity portion and an upper housing surrounding an upper side of the filter portion, the upper housing being fixed to the lower housing.

[0009] In some examples, the cavity portion may include: an inner tube forming a conduit for supplying the coating solution in a width direction of the shell portion, the upper side of the inner tube being open; and a supply tube configured to supply the coating solution to the inner tube, the supply tube having a first side connected to the inner tube and a second side extending to the outside of the shell portion.

[0010] In some examples, the exhaust portion may include: an exhaust cover covering an upper side of the filter portion, the exhaust cover configured to collect gas from the filter portion; and an exhaust pipe extending from the exhaust cover to an outside of the housing portion, the exhaust pipe configured to guide the exhaust of the gas.

[0011] In some examples, the filter portion may include: a filter frame located between the exhaust portion and the cavity portion, a plurality of holes being formed in the filter frame in a vertical direction; and a filter member detachably mounted within the filter frame and configured to allow gas from the coating solution to pass therethrough and prevent liquid from the coating solution from passing therethrough.

[0012] In some examples, the filter frame may include: a first support member formed in a plate shape and covering the upper side of the cavity portion, a first connection hole formed in the first support member so that gas can pass through the first support member; a second support member located above the first support member, a second connection hole formed in the second support member at a position facing the first connection hole and allowing gas to pass through the second support member; and a connecting member connecting the first support member and the second support member.

[0013] In some examples, the filter member may be located between the first support member and the second support member.

[0014] In some examples, the first connecting hole has an inner diameter that gradually narrows toward an upper side where the filter member is located.

[0015] In some examples, the second connecting hole has an inner diameter that gradually narrows toward a lower side where the filter member is located.

[0016] In some examples, the filter portion may be attachable to and detachable from the housing portion by a sliding operation.

[0017] An exemplary secondary battery manufacturing device for solving the above technical problems according to an embodiment of the present disclosure includes: a shell portion, provided with a nozzle, which is configured to face a substrate being moved by a coating roller; a cavity portion, located within the shell portion, the cavity portion forming a conduit for delivering a coating solution to the nozzle; an exhaust portion, having a first side surrounding an opening of the cavity portion and a second side extending to the outside of the shell portion to form a path for exhausting gas; a filter portion, located between the cavity portion and the exhaust portion, the filter portion being configured to guide the gas contained in the coating solution in a direction toward the exhaust portion; and a guide portion, fixed to the shell portion, the guide portion being configured to guide the sliding movement of the filter portion.

[0018] In some examples, the guide portion may include: a guide body installed at opposite sides of the filter portion in a width direction and extending along a direction in which the filter portion moves when guided into the housing portion; and a guide groove formed in a longitudinal direction of the guide body.

[0019] In some examples, the filter portion may include: a filter frame located between the exhaust portion and the cavity portion, a plurality of holes formed in the filter frame in a vertical direction, the filter frame being configured so that a sliding movement of the filter frame can be guided by the guide portion; and a filter member detachably located within the filter frame, the filter member being configured to allow gas from the coating solution to pass therethrough and prevent liquid from the coating solution from passing therethrough.

[0020] In some examples, the filter frame may include: a first support member formed in a plate shape and covering an upper side of a cavity portion, a first connection hole formed in the first support member so that gas can pass through the first support member; a second support member located above the first support member, a second connection hole formed in the second connection member at a position facing the first connection hole, and the filter member located between the first connection hole and the second connection hole; a connecting member connecting the first support member and the second support member; and a wing member extending in a lateral direction of the connecting member and including a guide protrusion located in a guide groove.

[0021] In some examples, the filtration member may include a membrane filter.

[0022] In some examples, the secondary battery manufacturing apparatus may further include an airtight plate supporting a lower side of the filter portion, positioned along an outer circumference of the cavity portion, and configured to guide the coating solution from the cavity portion to the nozzle. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Since the following drawings attached to this specification illustrate preferred embodiments of the present disclosure and, together with the following detailed description of the present disclosure, are used to help further understand the technical spirit of the present disclosure, the present disclosure should not be understood as being limited to the items disclosed in the drawings:

[0024] Figure 1 is a side view showing an exemplary secondary battery manufacturing apparatus according to the present disclosure;

[0025] Figure 2 is an exploded perspective view showing an exemplary secondary battery manufacturing apparatus according to the present disclosure;

[0026] Figure 3 is a perspective view showing an exemplary secondary battery manufacturing apparatus according to the present disclosure;

[0027] Figure 4 is a side sectional view showing an exemplary secondary battery manufacturing apparatus according to the present disclosure;

[0028] Figure 5 is a front view showing a state in which an exemplary filter frame according to the present disclosure is connected to a guide portion;

[0029] Figure 6 is a side sectional view showing an installed state of an exemplary locking portion according to the present disclosure;

[0030] Figure 7 is a cross-sectional view illustrating an exemplary filter portion according to the present disclosure;

[0031] Figure 8 is a bottom view illustrating an exemplary first support member according to the present disclosure; and

[0032] Figure 9 and Figure 10 is a graph illustrating liquid entry pressure (LEP) as a function of pore size for an exemplary filter member according to the present disclosure. DETAILED DESCRIPTION

[0033] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts consistent with the proposed technical spirit of the present disclosure, based on the principle that the inventor can appropriately define the concept of the term to describe his / her invention in the best way. Therefore, since the embodiments disclosed in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present disclosure and do not represent the entire technical spirit of the present disclosure, it should be understood that there are various equivalents and modifications that can replace them when submitting this application.

[0034] In addition, when used in this specification, "include or include" and / or "including... or including..." specifies the existence of the mentioned shapes, numbers, steps, operations, components and / or their groups, and does not exclude the existence or addition of one or more other shapes, numbers, steps, operations, components and / or their groups.

[0035] In addition, in order to help understand the present invention, the accompanying drawings are not drawn to scale, and the sizes of some components may be exaggerated. In addition, in different embodiments, the same reference numerals may be given to the same components.

[0036] Stating that two objects being compared are "the same" means that the two objects are "substantially the same." Thus, "substantially the same" can include deviations that are considered low in the art, for example, within 5%. Furthermore, uniformity of a parameter in a region can refer to uniformity from an average perspective.

[0037] Although the terms "first", "second", etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another component, and unless otherwise stated, the first component may also be the second component.

[0038] Throughout the specification, unless otherwise stated, each component may be singular or plural.

[0039] An arbitrary component being disposed at the “upper (or lower) part” of a component or being “on (or under) the component” means that the arbitrary component may be disposed in contact with the upper surface (or lower surface) of the component, or another component may be interposed between the component and the arbitrary component disposed on (or under) the component.

[0040] In addition, when describing that a certain component is “connected,” “coupled,” or “linked” to another component, it should be understood that these components may be directly connected or linked to each other, but another component may be “interposed” between these components, or these components may be “connected,” “coupled,” or “linked” through another component. In addition, the case where a specific component is electrically connected to another component includes not only the case where these components are directly connected, but also the case where these components are connected through another element therebetween.

[0041] Throughout the specification, unless otherwise stated, "A and / or B" means A, B, or A and B. That is, "and / or" includes all or any combination of multiple listed items. Unless otherwise stated, "C to D" means greater than or equal to C and less than or equal to D.

[0042] The terms used in this specification are provided to describe the embodiments of the present disclosure and are not intended to limit the present disclosure.

[0043] Figure 1 is a side view showing an exemplary secondary battery manufacturing apparatus 1 according to the present disclosure, Figure 2 is an exploded perspective view showing an exemplary secondary battery manufacturing apparatus 1 according to the present disclosure, Figure 4 is a side sectional view showing an exemplary secondary battery manufacturing apparatus 1 according to the present disclosure.

[0044] like Figure 1 、 Figure 2 and Figure 4 As shown, the exemplary secondary battery manufacturing device 1 according to the present disclosure includes a housing portion 20, a cavity portion 30, a venting portion 40, and a filtering portion 50. In some examples, the exemplary secondary battery manufacturing device 1 may further include a guide portion 100, an airtight plate 110, and a locking portion 120 (see FIG. Figure 6 ). In the present disclosure, the secondary battery manufacturing apparatus 1 may be referred to as a slit coater.

[0045] In the secondary battery manufacturing device 1, a filter member 90 including a porous membrane may be installed on the cavity portion 30 for supplying the liquid slurry and the vent portion 40. The vent portion 40 may extend to the outside of the housing portion 20 to suppress leakage of the slurry and allow only bubbles to be removed from the slurry. In the present disclosure, bubbles contained in the slurry may be referred to as gas.

[0046] Since only the bubbles contained in the slurry can be discharged to the outside of the housing portion 20, slurry leakage can be suppressed and manufacturing costs can be reduced because less additional work by workers is required. When only the exhaust portion 40 is installed without the filter portion 50, there may be a problem that the slurry is discharged to the outside of the housing portion 20 together with the gas. In addition, when only the exhaust portion 40 is installed without the filter portion 50, since only the bubbles at the specific portion where the exhaust portion 40 is installed are removed, work efficiency may deteriorate. However, when the filter portion 50 using a porous membrane is installed together with the exhaust portion 40, bubbles can be removed from the entire opening area of ​​the cavity portion 30.

[0047] A substrate 12, which is an electrode plate for a secondary battery, is moved by a coating roller 10. The secondary battery manufacturing apparatus 1 is installed at a position facing the coating roller 10. The secondary battery manufacturing apparatus 1 can coat the exterior of the substrate 12 with an active material using a slit coater. A coating solution as a liquid slurry is discharged from the slit coater and fixed to the exterior of the substrate 12. The substrate 12 can be used for a negative electrode or a positive electrode.

[0048] Regarding the technical concept of the housing portion 20 , various alternatives are possible, including providing the nozzle 26 at a position facing the substrate 12 moved by the coating roller 10 . The housing portion 20 according to one embodiment of the present disclosure includes an upper housing 22 and a lower housing 24 .

[0049] The lower housing 24 is installed in a shape surrounding the lower portion of the cavity portion 30. The upper side of the lower housing 24 is open. The lower housing 24 is formed into a concave shape toward the upper side and may have a length in the width direction (X) corresponding to the length of the substrate 12 in the width direction (X). The cavity portion 30 may be located inside the lower housing 24. A nozzle 26, which serves as a hole for discharging the coating solution, may be provided in the lower housing 24 facing the substrate 12. The nozzle 26 may include a groove extending from the upper end of the lower housing 24 in the width direction (X) of the lower housing 24. The nozzle 26 forms a path for discharging the coating solution that has passed through the cavity portion 30 onto the substrate 12.

[0050] The upper housing 22 surrounds the upper side of the filter portion 50 and is fixed to the lower housing 24. The upper housing 22 may have a concave shape toward the lower side and may be fixed to the lower housing 24 while surrounding the filter portion 50 and the exhaust portion 40. The upper housing 22 and the lower housing 24 may be integrally formed, and various alternatives are possible, such as the housing being composed of three or more parts as needed.

[0051] Various alternatives are possible regarding the technical concept that cavity portion 30 forms a conduit located inside housing portion 20 and provides a conduit for delivering the coating solution to nozzle 26. Cavity portion 30 according to one embodiment of the present disclosure includes an inner tube 32 and a supply tube 34.

[0052] Inner tube 32 forms a conduit for supplying coating solution in the width direction (X) of housing portion 20 and has an open upper side. Inner tube 32 extends in the width direction (X) of housing portion 20 and is in fluid communication with nozzle 26 of housing portion 20.

[0053] Since one side of supply tube 34 is connected to inner tube 32 and the other side of supply tube 34 extends outside housing portion 20, supply tube 34 forms a conduit for supplying the coating solution to inner tube 32. In this disclosure, the coating solution may be referred to as a slurry as described throughout this disclosure.

[0054] Regarding the technical concept that one side of the exhaust portion 40 is installed in a shape surrounding the opening of the cavity portion 30 and the other side of the exhaust portion 40 extends to the outside of the housing portion 20 to form a path for exhaust gas, various alternatives are possible. According to one embodiment of the present disclosure, the exhaust portion 40 includes an exhaust cover 42 and an exhaust pipe 44.

[0055] Regarding the technical concept of the exhaust cover 42 covering the upper side of the filter portion 50 and collecting the gas moving from the upper side of the filter portion 50, various alternatives are possible. According to one embodiment of the present disclosure, the lower side of the exhaust cover 42 is open toward the filter portion 50, and the exhaust cover 42 guides the gas that has passed through the filter portion 50. The exhaust cover 42 may have a shape that gradually narrows from the lower side to the upper side.

[0056] An exhaust pipe 44 is connected to the upper side of the exhaust cover 42 to serve as a gas exhaust path. Regarding the technical concept of extending the exhaust pipe 44 from the exhaust cover 42 to the exterior of the housing portion 20 to guide the exhaust of gas, various alternatives are possible. According to one embodiment of the present disclosure, the exhaust pipe 44 may have a tubular shape extending upward from the upper side of the exhaust cover 42 and protruding to the exterior of the housing portion 20. Gas discharged to the upper side of the filter portion 50 is guided to the exhaust pipe 44 by the exhaust cover 42 and discharged to the exterior of the housing portion 20 through the exhaust pipe 44.

[0057] Regarding the technical concept that the filter portion 50 is located between the cavity portion 30 and the exhaust portion 40 and allows only the gas contained in the coating solution to move in the direction toward the exhaust portion 40, various alternatives are possible. The filter portion 50 can be attached to and detached from the housing portion 20 by a sliding operation. A space for installing the filter portion 50 is provided inside the housing portion 20, and the filter of the filter portion 50 operated in a sliding manner can be easily replaced.

[0058] Filter portion 50 is mounted on inner tube 32 provided in cavity portion 30, and exhaust portion 40 is mounted on filter portion 50. Therefore, the gas contained in the coating solution moving to nozzle 26 through inner tube 32 passes through filter portion 50 and is then discharged to the outside of housing portion 20 through exhaust portion 40. In addition, the liquid coating solution may not pass through filter portion 50, and thus, the liquid coating solution is discharged only through nozzle 26.

[0059] The filter portion 50 according to one embodiment of the present disclosure may include a filter frame 60 and a filter member 90. Since the filter portion 50 is detachably mounted in the housing portion 20 in a sliding manner, the process of replacing the filter frame 60 and the filter member 90 can be performed without disassembling the housing portion 20. The filter member 90 may include a porous membrane.

[0060] Regarding the technical concept of the filter frame 60 being located between the exhaust portion 40 and the cavity portion 30, having a plurality of holes formed in the vertical direction (Z), and supporting the filter member 90, various alternatives are possible. The sliding movement of the filter frame 60 is guided by the guide portion 100. In the present disclosure, the filter member 90 may include or be referred to as a membrane or a porous membrane.

[0061] The filter frame 60 supporting the filter member 90 may include a plurality of connection holes to facilitate the collection of bubbles. Since the filter frame 60 is formed with a groove having a concave shape toward the filter member 90, bubbles contained in the coating solution are gathered in the concave groove provided in the filter frame 60, and thus, the bubbles can be collected relatively easily and quickly.

[0062] Since the pores of the filter member 90 may be clogged with slurry particles as the operating time increases, the filter member 90 including the porous membrane may be periodically replaced.

[0063] Figure 7 is a cross-sectional view showing an exemplary filter portion 50 according to the present disclosure, Figure 8 FIG is a bottom view showing an exemplary first support member 62 according to the present disclosure. Figure 2 、 Figure 7 and Figure 8 As shown, the filter frame 60 according to one embodiment of the present disclosure may include a first support member 62 , a second support member 66 , and a connecting member 70 . In some examples, the filter frame 60 may further include a wing member 80 .

[0064] Regarding the technical concept of forming the first support member 62 into a plate shape covering the upper side of the cavity portion 30 and including the first connection hole 64 through which gas passes, various alternatives are possible. The first connection hole 64 may have an inner diameter that gradually narrows toward the upper side where the filter member 90 is located. The diameter of the first connection hole 64 may be 100 μm or greater, which is larger than the pore size of the porous membrane of the filter member 90 (1 μm or less).

[0065] The first support member 62 can be formed in a plate shape, and the filter member 90 is mounted on the first support member 62. The first support member 62 can be mounted so as to contact the coating solution within the cavity portion 30. The first connection holes 64 can be treated with hydrophobicity so that only bubbles contained in the coating solution can move through the first connection holes 64 to the filter member 90, thereby preventing the coating solution from moving to the filter member 90 through the first connection holes 64. A hydrophobic coating or application can be performed on the inner surface of the first support member 62 facing the first connection holes 64. Multiple first connection holes 64 are provided in the first support member 62 and extend in a vertical direction. The path of the first connection holes 64 gradually narrows from the bottom to the top. Therefore, only bubbles in the coating solution located below the first connection holes 64 can be collected by the first connection holes 64 and move to the filter member 90 on the top. Therefore, the liquid coating solution can not move upward through the first connection holes 64 that have been treated with hydrophobicity.

[0066] The first supporting member 62 may be formed in a flat plate shape, and a hydrophilic treatment may be performed on the lower side surface of the first supporting member 62 facing the cavity portion 30. Since the hydrophilic coating or application is performed on the lower side surface of the first supporting member 62, the liquid coating solution exists on the lower side surface of the first supporting member 62, and only bubbles can move to the first connection hole 64 having a concave groove shape.

[0067] When a hydrophobic surface and a hydrophilic surface are adjacent to each other, bubbles are more attracted to the hydrophobic surface side, so bubbles can be induced to the hydrophobic surface. Since the surface free energy is smaller in the concave portion (where the first connection hole 64 is formed in the lower surface of the first support member 62), bubbles can be collected more easily than on a flat surface.

[0068] When the bubbles induced to the hydrophobic surface of the first connection hole 64 pass through the small holes of the hydrophobically treated filter member 90, only the bubbles can be discharged to the upper side of the filter member 90 without leakage of the coating solution. In the operation of discharging gas only to the upper side of the filter frame 60, the capillary phenomenon is utilized, and within a certain pressure range, only gas can be removed from the system without leakage of liquid.

[0069] When a membrane is used as the filtration member 90, the liquid entry pressure (LEP) at which liquid begins to leak through the pores of the membrane can be given by the following Young-Laplace equation:

[0070]

[0071] Where P1 is the pressure inside the system and the pressure at the bottom side of filter member 90, P0 is the pressure outside the system and the pressure at the top side of filter member 90, γ is the surface tension of the liquid coating solution, α is the contact angle between the liquid coating solution and filter member 90, and d is the diameter of the pores provided in filter member 90. When the pressure difference between the inside and outside increases, α also increases, and when α exceeds a certain value, the liquid leaks to the outside of the system through the pores. The contact angle α is sensitively affected by the surface treatment state.

[0072] In order to suppress leakage of the coating solution through the filter member 90, it is preferred that the LEP value is as high as possible, the contact angle is large, and the pore size of the membrane is small. When a porous membrane is used as the filter member 90, more efficient bubble removal can be performed.

[0073] About the second support member 66, be positioned on the first support member 62 and comprise second connecting hole 68 in the position facing the first connecting hole 64 to make the technical conception of filter member 90 between them, various alternatives are possible.A plurality of second connecting holes 68 can be provided to extend in the vertical direction.The second connecting hole 68 has the internal diameter that narrows gradually towards the downside where filter member 90 is.The second support member 66 has a plate shape and is spaced apart from the first support member 62.The filter mounting groove 72 that is used to install filter member 90 is provided between the first support member 62 and the second support member 66.

[0074] Since the first connection holes 64 and the second connection holes 68 are installed in a position facing each other with the filter member 90 therebetween, gas can be discharged more smoothly. The inner surface of the second support member 66 facing the second connection holes 68 can also be subjected to a hydrophobic surface treatment. The diameter of the first connection holes 64 can be 200±50μm, and the distance between adjacent first connection holes 64 can be 500±100μm. The diameter of the second connection holes 68 can be 200±50μm, and the distance between adjacent second connection holes 68 can be 500±100μm.

[0075] A hydrophobic material is coated on the inner surface of first connection hole 64, and may also be coated on the inner surface of second connection hole 68. When the coating solution is a negative electrode slurry, the coating solution includes distilled water or water and is therefore hydrophilic. Therefore, the coating solution is directed to the lower surface of first support member 62, on which the hydrophilic coating is formed, and is prevented from moving to first connection hole 64, on which the hydrophobic coating is formed. However, bubbles contained in the coating solution are not affected by the hydrophobic coating and are collected in first connection hole 64, which is formed into a concave groove shape. The bubbles then pass through filter member 90 and second connection hole 68 and move to exhaust portion 40.

[0076] The hydrophobic material contained in the hydrophobic coating should have stable properties so that the coating will not participate in the electrochemical reaction in the secondary battery. The hydrophobic coating used in the present disclosure may include at least one of nano-silica, fluorinated nano-silica, polyurethane, non-acetic acid silicon and fluorocarbon. Fluorocarbons are compounds composed of carbon atoms and fluorine atoms and have unique chemical and physical properties. Fluorocarbon molecules have a structure in which one or more carbon atoms are replaced by one or more fluorine atoms.

[0077] Various alternatives are possible regarding the technical concept of connecting the first and second support members 62 and 66 using the connecting member 70. According to one embodiment of the present disclosure, the connecting member 70 is mounted on both sides of the first and second support members 62 and 66 in the width direction (X) and extends in the vertical direction (Z) to connect the first and second support members 62 and 66. The length of the connecting member 70 in the vertical direction (Z) may correspond to the thickness of the filter member 90 in the vertical direction (Z).

[0078] The filter portion 50 may be detachably mounted in the housing portion 20. The filter portion 50 may be mounted in the housing portion 20 by sliding movement in a horizontal direction. In addition, the filter portion 50 may be attached to or detached from the housing portion 20 in various ways.

[0079] Figure 3 is a perspective view showing an exemplary secondary battery manufacturing apparatus 1 according to the present disclosure, Figure 5 1 is a front view showing a state in which an exemplary filter frame 60 according to the present disclosure is connected to the guide portion 100. Figure 3 and Figure 5 As shown, since the wing member 80 provided with the filter portion 50 moves along the guide portion 100 installed in the housing portion 20 , the filter portion 50 can be attached to and detached from the housing portion 20 .

[0080] Regarding the technical concept of the wing members 80 extending transversely of the connecting member 70 and including guide protrusions 82 associated with guide grooves 104, various alternatives are possible. The wing members 80 are mounted on both sides of the filter frame 60 in the width direction (X). The wing members 80 may be integrally formed with the connecting member 70, or they may be manufactured separately and coupled to the connecting member 70. The guide protrusions 82 projecting upward from the wing members 80 are inserted into and associated with guide grooves 104 of the guide portion 100 fixed to the housing portion 20, thereby guiding the sliding movement of the filter frame 60.

[0081] Various alternatives are possible regarding the technical concept that the guide portion 100 is fixed to the housing portion 20 and guides the sliding movement of the filter portion 50. The guide portion 100 according to one embodiment of the present disclosure may include a guide body 102 and a guide groove 104.

[0082] Various alternatives are possible regarding the technical concept that the guide body 102 is installed on both sides of the filter part 50 in the width direction (X) and extends along the moving direction of the filter part 50 . The guide body 102 is formed in a quadrangular rod shape and can be fixed to the upper case 22 .

[0083] Regarding the technical concept of guide groove 104 forming a groove in the longitudinal direction (Y) of guide body 102, various alternatives are possible. According to one embodiment of the present disclosure, guide groove 104 may form a "T"-shaped groove, and guide protrusion 82 may form a "T"-shaped protrusion. When guide protrusion 82 is located in guide groove 104, horizontal movement of filter frame 60 can be guided.

[0084] Figure 6 The figure is a side cross-sectional view illustrating an exemplary locking portion 120 according to the present disclosure. Regarding the technical concept of providing a locking structure for the locking portion 120 to prevent the filter portion 50 from detaching from the housing portion 20, various alternatives are possible. By installing the locking portion 120, the filter portion 50 installed in the housing portion 20 can be prevented from inadvertently detaching from the housing portion 20. The locking portion 120 according to one embodiment of the present disclosure is located outside the housing portion 20 and is secured while surrounding the lower housing portion 24, with the guide portion 100 protruding from the outside of the housing portion 20. The locking portion 120 according to one embodiment of the present disclosure includes a locking body 122 and a locking protrusion 124. The locking body 122 has a rod shape extending in the vertical direction (Z). The locking protrusion 124 extends from the upper and lower sides of the locking body 122 toward the housing portion 20. The upper locking protrusion 124 is positioned above the guide portion 100, while the lower locking protrusion 124 is positioned below the lower housing portion 24, thereby restricting movement of the locking protrusion 124. The filter portion 50 and the airtight plate 110 (to be described below) are located in the lateral direction of the locking body 122. Since the locking portion 120 is fixed to the guide portion 100 and the lower housing 24 in a forced-fit manner, the filter portion 50 is restricted by the locking body 122, and thus the lateral movement of the locking protrusion 124 is restricted.

[0085] like Figure 2 As shown, the airtight plate 110 supports the lower side of the filter portion 50 and is installed along the outer periphery of the cavity portion 30. Regarding the technical concept of the airtight plate 110 guiding the coating solution to move from the cavity portion 30 to the nozzle 26, various alternatives are possible. The filter portion 50 and the guide portion 100 can be located on the airtight plate 110 so that the flow of the coating solution from the cavity portion 30 to the nozzle 26 is not affected. Due to the installation of the airtight plate 110, the filter portion 50 can be kept spaced apart from the cavity portion 30 by a set distance and does not contact the cavity portion 30. Since the airtight plate 110 is installed along the upper opening of the inner tube 32 provided in the cavity portion 30, the coating solution discharged from the inner tube 32 is blocked from moving in directions other than the direction toward the nozzle 26. In addition, by only replacing the airtight plate 110, a flow path suitable for coating conditions can be formed.

[0086] The airtight plate 110 according to one embodiment of the present disclosure may include a first airtight member 112 having a shape surrounding the rear portion of the inner tube 32 and a second airtight member 114 connected to both sides of the first airtight member 112 in the width direction. The wing members 80 may be located on the second airtight member 114. The second airtight member 114 is located on both sides of the inner tube 32 in the width direction and guides the coating solution moved to the upper side of the inner tube 32 in the forward direction toward the nozzle 26.

[0087] Regarding the technical concept that the filter member 90 is detachably mounted within the filter frame 60 and only allows gas from the coating solution to pass therethrough, various alternatives are possible. The filter member 90 can be mounted between the first support member 62 and the second support member 66. In some examples, the filter member 90 can include a membrane filter.

[0088] The porous membrane as the filter member 90 may include at least one of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), perfluoroalkoxy (PFA), and ethylene-tetrafluoroethylene copolymer (ETFE).

[0089] Because a porous membrane is used as filter member 90, the liquid coating solution cannot pass through filter member 90, and only gas can pass through filter member 90, so gas can be removed from the coating solution. The pressure in secondary battery manufacturing apparatus 1 may rise intermittently due to the operation of the pump supplying the slurry (coating solution), and even in such cases, leakage of the liquid coating solution through filter member 90 can be prevented. To this end, the LEP value (which can be calculated using the Young-Laplace equation described above) is preferably high. To achieve a high LEP value, the membrane contact angle should be large and the membrane pore size should be small.

[0090] Since the minimum pressure for discharging the slurry through the nozzle 26 does not exceed 10 bar under general coating conditions, when the LEP is greater than 10 bar, leakage of the slurry does not occur and bubbles can be removed stably. Among various possible membranes, PVDF has the largest contact angle and its LEP value is also high; when the pore size of the membrane made of PVDF is 0.2 μm or less, the LEP is 10 or more, which is satisfactory for the purposes of the present disclosure.

[0091] Figure 9 is a graph showing liquid entry pressure (LEP) according to pore size for an exemplary filter member 90 according to the present disclosure. Specifically, Figure 9 This is a graph showing the results of calculating LEP values ​​based on the pore sizes of membranes made of hydrophobic materials such as PVDF, PFA, PTFE, and ETFE.

[0092] exist Figure 9 In the graph shown, the contact angle of PTFE is 110°, the contact angle of PFA is 115°, the contact angle of ETFE is 96°, and the contact angle of PVDF is 140°.

[0093] Considering that the surface tension of water used as a solvent for the negative electrode slurry is 0.072 N / m, Figure 9 It can be seen that PVDF with a large contact angle can withstand the highest pressure range, and the LEP value increases significantly as the pore size decreases.

[0094] At the same time, as the surface tension γ decreases, the LEP also decreases proportionally to the surface tension γ. N-methyl-2-pyrrolidone (NMP), commonly used as a solvent for positive electrode slurries, has a surface tension approximately 0.040 N / m lower than that of water. Depending on its composition, negative electrode slurries can also have a surface tension lower than that of water as a solvent. Therefore, by calculating the LEP value at low surface tension values, the range of physical properties and the like for which the present disclosure is effective can be obtained.

[0095] Figure 10 is a graph illustrating liquid entry pressure (LEP) as a function of pore size for an exemplary filter member 90 according to the present disclosure. Figure 10 The LEP calculation results of 0.024 N / m, which is 1 / 3 of the surface tension value of water, are shown as a graph. Figure 10 The resulting values ​​in [ ] include a range of physical properties for typical slurries, assuming that the surface tension of the slurry is very low. The pressure applied to the interior of cavity portion 30 is several tens of kPa, and it can be assumed that slurry leakage will not occur when the LEP is 1 bar or greater. However, since pulsation may occur when driving an actual pump, setting an LEP of 3 bar or greater as a safety margin is more stable. The hydrophobic physical properties and pore size of the membrane serving as filter member 90 may be limited based on these values.

[0096] In the filter member 90 according to one embodiment of the present disclosure, the membrane is formed of PVDF, which is a material having a contact angle of 140° or greater (a value indicating hydrophobic physical properties). Preferably, the pore size is small, and for materials having a large contact angle (such as PVDF), even when a membrane having a pore size of 0.2 μm is used, bubbles can be removed from the coating solution while suppressing slurry leakage.

[0097] According to the present disclosure, since bubbles introduced into the slurry are separated from the slurry, the defect rate of the secondary battery may be reduced.

[0098] Furthermore, according to the present disclosure, since only bubbles introduced into the slurry are discharged to the outside air and leakage of the slurry is prevented, additional work for collecting the slurry is omitted, and thus manufacturing costs may be reduced.

[0099] However, the effects that can be obtained by the present disclosure are not limited to the above-mentioned effects, and other technical effects that are not mentioned will be clearly understood by those skilled in the art from the above description.

[0100] Although the present disclosure is described above with limited examples and drawings, the present disclosure is not limited thereto, and those skilled in the art may make various modifications and changes within the technical spirit of the present disclosure and the equivalent scope of the claims described above.

[0101] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0024832 filed on February 21, 2024, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.

Claims

1. A secondary battery manufacturing device comprising: a housing portion provided with a nozzle configured to face the substrate being moved by the coating roller; a cavity portion located inside the housing portion, the cavity portion forming a conduit for delivering the coating solution to the nozzle; an exhaust portion having a first side surrounding the opening of the cavity portion and a second side extending outwardly from the housing portion to form a passage for exhausting gas; as well as A filter portion is located between the cavity portion and the exhaust portion, the filter portion being configured to guide gas contained in the coating solution toward the exhaust portion and prevent liquid of the coating solution from being guided to the exhaust portion. 2 . The secondary battery manufacturing apparatus according to claim 1 , wherein the case portion includes a lower case surrounding a lower portion of the cavity portion and an upper case surrounding an upper side of the filter portion, the upper case being fixed to the lower case.

3. The secondary battery manufacturing apparatus according to claim 1, wherein the cavity portion comprises: an inner tube forming a conduit for supplying the coating solution in a width direction of the housing portion, the upper side of the inner tube being open; as well as A supply pipe is configured to supply the coating solution to the inner pipe, the supply pipe having a first side connected to the inner pipe and a second side extending to the outside of the housing portion.

4. The secondary battery manufacturing apparatus according to claim 1, wherein the exhaust portion comprises: an exhaust cover covering an upper side of the filter portion, the exhaust cover being configured to collect gas from the filter portion; as well as An exhaust pipe extends from the exhaust cover to the outside of the housing portion, and is configured to guide the exhaust of the gas.

5. The secondary battery manufacturing apparatus according to claim 1, wherein the filter portion comprises: a filter frame located between the exhaust portion and the cavity portion, wherein a plurality of holes are formed in the filter frame in a vertical direction; as well as A filter member is detachably mounted inside the filter frame and configured to allow the gas from the coating solution to pass therethrough and prevent the liquid of the coating solution from passing therethrough.

6. The secondary battery manufacturing apparatus according to claim 5, wherein the filter frame comprises: a first supporting member formed in a plate shape and covering an upper side of the cavity portion, a first connecting hole formed in the first supporting member so that the gas can pass through the first supporting member; a second supporting member located above the first supporting member, a second connecting hole formed in the second supporting member at a position facing the first connecting hole and enabling the gas to pass through the second supporting member; as well as a connecting member connecting the first supporting member and the second supporting member, The filter member is located between the first support member and the second support member. 7 . The secondary battery manufacturing apparatus according to claim 6 , wherein the first connection hole has an inner diameter gradually narrowing toward an upper side where the filter member is located. 8 . The secondary battery manufacturing apparatus according to claim 6 , wherein the second connection hole has an inner diameter gradually narrowing toward a lower side where the filter member is located. 9 . The secondary battery manufacturing apparatus according to claim 1 , wherein the filter portion is attachable to and detachable from the case portion by a sliding operation.

10. A secondary battery manufacturing device comprising: a housing portion provided with a nozzle configured to face the substrate being moved by the coating roller; a cavity portion located inside the housing portion, the cavity portion forming a conduit for delivering the coating solution to the nozzle; an exhaust portion having a first side surrounding the opening of the cavity portion and a second side extending to the exterior of the housing portion to form a path for exhausting gas; a filter portion located between the cavity portion and the exhaust portion, the filter portion configured to guide gas contained in the coating solution in a direction toward the exhaust portion; as well as A guide portion is fixed to the housing portion, the guide portion being configured to guide a sliding movement of the filter portion.

11. The secondary battery manufacturing apparatus according to claim 10, wherein the guide portion comprises: guide bodies installed at opposite sides of the filter portion in the width direction and extending in a direction in which the filter portion moves when being guided into the housing portion; as well as A guide groove is formed in a longitudinal direction of the guide body.

12. The secondary battery manufacturing apparatus according to claim 11, wherein the filter portion comprises: a filter frame located between the exhaust portion and the cavity portion, a plurality of holes being formed in the filter frame in a vertical direction, the filter frame being configured so that a sliding movement of the filter frame can be guided by the guide portion; as well as A filter member is removably positioned within the filter frame, the filter member being configured to allow gas from the coating solution to pass therethrough and to prevent liquid from the coating solution from passing therethrough.

13. The secondary battery manufacturing apparatus according to claim 12, wherein the filter frame comprises: a first supporting member formed in a plate shape and covering an upper side of the cavity portion, a first connecting hole formed in the first supporting member so that the gas can pass through the first supporting member; a second supporting member located above the first supporting member, a second connecting hole formed in the second supporting member at a position facing the first connecting hole, and the filter member located between the first connecting hole and the second connecting hole; a connecting member connecting the first supporting member and the second supporting member; as well as A wing member extends in a lateral direction of the connecting member and includes a guide protrusion located in the guide groove. 14 . The secondary battery manufacturing apparatus according to claim 12 , wherein the filter member comprises a membrane filter. 15 . The secondary battery manufacturing apparatus according to claim 10 , further comprising an airtight plate supporting a lower side of the filter portion, positioned along an outer circumference of the cavity portion, and configured to guide the coating solution to move from the cavity portion to the nozzle.

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