Separator coating roller capable of pattern coating and separator manufacturing device comprising same

Abstract

The present invention relates to a separator coating roller capable of forming, by means of pattern coating, a coating layer having varying thicknesses in the longitudinal direction, and a separator manufacturing device comprising same. The separator coating roller, according to an embodiment of the present invention, comprises a coating bar, a reference bearing, and a variable bearing unit. The coating bar forms a coating layer on a separator substrate. The reference bearing is formed to surround the outer circumferential surface of the coating bar. The variable bearing unit is disposed on the outside of the reference bearing to surround the outer circumferential surface of the coating bar and can adjust the curvature of the coating bar by varying in position.

Description

Separator coating roller capable of pattern coating and separator manufacturing apparatus including the same

[0001] The present invention relates to a separator coating roller for manufacturing a separator for a secondary battery, and more specifically, to a separator coating roller capable of pattern coating in which the thickness of the coating layer varies in the longitudinal direction, and a separator manufacturing apparatus including the same.

[0002] Recently, interest in energy storage technology has been steadily increasing. As application fields expand to include energy for mobile phones, camcorders, laptop PCs, and even electric vehicles, efforts in the research and development of electrochemical devices are becoming increasingly concrete.

[0003] Electrochemical devices are the most 주목받는 field in this regard, and among them, the development of rechargeable secondary batteries is the focus of interest. Recently, active research and development on new electrode and battery designs is being conducted to improve capacity density and specific energy in the development of secondary batteries.

[0004] Among the secondary batteries currently in use, lithium secondary batteries developed in the early 1990s are gaining attention for their advantages of having a higher operating voltage and significantly higher energy density compared to conventional batteries such as Ni-MH, Ni-Cd, and lead-acid batteries that use aqueous electrolytes.

[0005] Among these, the separator used in lithium-ion batteries plays the role of allowing the movement of lithium ions while physically blocking contact between the anode and cathode and electrically insulating them. In particular, the separator is known to have a significant impact on battery characteristics and safety, as it is responsible for maintaining insulation to prevent internal short circuits.

[0006] These separators primarily use porous polymer substrates, but porous polymer substrates have a problem in that they can cause internal short circuits between the anode and cathode due to thermal shrinkage at high temperatures. To improve this, an organic / inorganic porous coating layer containing inorganic particles and a binder polymer is applied to the porous polymer substrate to reduce thermal shrinkage.

[0007] Meanwhile, if the thickness of the coating layer applied to the separator is uniform, ion movement may be inefficient in specific regions of the secondary battery. This hinders interaction with the electrolyte and can degrade the overall performance of the battery.

[0008] In addition, secondary batteries generate heat during operation, and if the thickness of the coating layer is uniform, heat distribution is uneven, causing heat concentration. Heat concentration can lead to overheating in some areas of the secondary battery, which may shorten the battery life or cause safety issues in the long term.

[0009] Furthermore, a separator of uniform thickness may not be able to uniformly withstand mechanical stresses, such as external pressure or expansion and contraction occurring within the battery. This can increase the likelihood of damage or short circuits occurring in specific areas.

[0010] The present invention aims to provide a separator coating roller capable of pattern coating in which the thickness of the coating layer varies in the longitudinal direction, and a separator manufacturing apparatus including the same.

[0011] A separator coating roller according to an embodiment of the present invention includes a coating bar, a reference bearing, and a variable bearing portion. The coating bar forms a coating layer on a separator substrate. The reference bearing is formed to surround the outer surface of the coating bar. The variable bearing portion is positioned outside the reference bearing to surround the outer surface of the coating bar and can adjust the curvature of the coating bar.

[0012] In a separator coating roller according to an embodiment of the present invention, the variable bearing portion includes a variable bearing, a bearing housing, and an adjustment bolt. The variable bearing is positioned to surround the outer surface of the coating bar. The bearing housing has a hollow and an insertion hole is formed that penetrates from the outer surface to the hollow. The adjustment bolt can be inserted into the insertion hole so that the insertion depth can be adjusted.

[0013] In a separator coating roller according to an embodiment of the present invention, the insertion holes may be formed in a plurality of pairs of two or more pairs facing each other. Among the plurality of pairs of insertion holes, the adjustment bolt inserted into the first pair of insertion holes fixes the variable bearing, and the adjustment bolt inserted into the second pair of insertion holes can adjust the position of the variable bearing.

[0014] In the separator coating roller according to an embodiment of the present invention, the diameter of the threads of the adjusting bolt may vary depending on the insertion position.

[0015] In the separator coating roller according to an embodiment of the present invention, the length of the adjusting bolt may vary depending on the insertion position.

[0016] In a separator coating roller according to an embodiment of the present invention, the insertion holes may be formed as a pair facing each other. The variable bearing portion is provided with a pair of side support members that protrude facing each other in the hollow to fix the variable bearing, and an adjustment bolt inserted into the pair of insertion holes can adjust the position of the variable bearing.

[0017] In a separator coating roller according to an embodiment of the present invention, insertion holes may be formed as a pair facing each other. In the hollow of the bearing housing, bearing guides that are planes facing each other are formed so that the variable bearing can move only in a straight direction within the hollow, and adjustment bolts inserted into the pair of insertion holes can adjust the position of the variable bearing.

[0018] In a separator coating roller according to an embodiment of the present invention, insertion holes may be formed as a pair facing each other. An adjustment bolt may be inserted into one of the insertion holes to adjust the position of a variable bearing, and a compression spring facing the adjustment bolt may be inserted into the other insertion hole.

[0019] In a separator coating roller according to an embodiment of the present invention, the variable bearing portion may have one insertion hole, a compression spring installed opposite to the one insertion hole, and a pair of side support members protruding opposite each other in the hollow to fix the variable bearing. An adjustment bolt inserted into the one insertion hole can adjust the position of the variable bearing.

[0020] In a separator coating roller according to an embodiment of the present invention, the variable bearing portion may have one insertion hole and a compression spring installed opposite to the one insertion hole. A bearing guide, which is a plane facing each other, is formed in the hollow so that the variable bearing can move only in a straight direction in the hollow, and an adjustment bolt inserted into the one insertion hole can adjust the position of the variable bearing.

[0021] In a separation membrane coating roller according to an embodiment of the present invention, an elastic buffer may be formed between the variable bearing and the outer surface of the coating bar to absorb friction caused by the coating bar bending due to a change in the position of the variable bearing.

[0022] In the separator coating roller according to an embodiment of the present invention, a wear-prevention pad may be formed at the location where the variable bearing and the adjustment bolt come into contact to prevent the surface of the variable bearing from being worn or damaged by the adjustment bolt.

[0023] In a separator coating roller according to an embodiment of the present invention, the curvature of the coating bar can be changed by changing the gap between the reference bearing and the variable bearing part.

[0024] A separator manufacturing apparatus according to an embodiment of the present invention comprises a substrate supply unit, a coating liquid receiving unit, and a coating roller. The substrate supply unit supplies a separator substrate. The coating liquid receiving unit receives a separator coating liquid. The coating roller forms a coating layer on the separator substrate supplied from the substrate supply unit using the coating liquid received in the coating liquid receiving unit. The coating roller is equipped with a coating bar, a reference bearing, and a variable bearing unit. The coating bar is positioned in the width direction of the separator substrate to apply the separator coating liquid to the separator substrate. The reference bearing is formed to surround the outer surface of the coating bar. The variable bearing unit is positioned outside the reference bearing to surround the outer surface of the coating bar and can adjust the curvature of the coating bar.

[0025] In a separator manufacturing apparatus according to an embodiment of the present invention, the variable bearing unit includes a variable bearing, a bearing housing, and an adjustment bolt. The variable bearing is positioned to surround the outer surface of a coating bar. The bearing housing has a hollow and an insertion hole is formed that penetrates from the outer surface to the hollow. The adjustment bolt can be inserted into the insertion hole so that the insertion depth can be adjusted.

[0026] The separator manufacturing apparatus according to an embodiment of the present invention may further include a kiss roller installed at the front and rear of the coating roller, respectively, to press the separator substrate in the direction of the coating roller.

[0027] In a membrane manufacturing apparatus according to an embodiment of the present invention, the rotational speed of the coating bar can be determined according to the curvature of the coating bar.

[0028] In a separator manufacturing device according to an embodiment of the present invention, the rotational speed of the roller of the substrate supply unit can be varied in conjunction with the rotational speed of the coating bar.

[0029] In a separator manufacturing apparatus according to an embodiment of the present invention, a coating roller is positioned on the upper and lower sides of a separator substrate to form a coating layer on both the upper and lower sides of the separator substrate.

[0030] According to the present invention, by enabling a pattern coating in which the thickness of the coating layer of a secondary battery separator varies in the longitudinal direction, the performance of the secondary battery can be optimized and safety maintained.

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

[0032] FIGS. 2A and FIGS. 2B are cross-sectional views showing a coating portion according to an embodiment of the present invention.

[0033] FIG. 3 is a perspective view showing a separator coating roller according to a first embodiment of the present invention.

[0034] FIG. 4 is a cross-sectional view showing a separator coating roller according to the first embodiment of the present invention.

[0035] Figure 5 is a view of the separator coating roller of Figure 4 from right to left (direction A).

[0036] FIG. 6 is a drawing showing a separator coating roller according to a second embodiment of the present invention.

[0037] FIG. 7 is a perspective view showing a separation membrane coating roller according to a third embodiment of the present invention.

[0038] FIG. 8 is a side view showing a separator coating roller according to a third embodiment of the present invention.

[0039] FIG. 9 is a perspective view showing a separator coating roller according to a fourth embodiment of the present invention.

[0040] FIG. 10 is a cross-sectional view showing a separator coating roller according to the fourth embodiment of the present invention.

[0041] FIGS. 11a, FIGS. 11b, and FIGS. 11c are cross-sectional views illustrating a separator coating roller according to a fifth embodiment of the present invention.

[0042] FIGS. 12a to 15 are drawings for explaining the operation process of a separator coating roller according to embodiments of the present invention.

[0043] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0044] The terms used in this invention are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this invention, terms such as "comprising" or "having" are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0045] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that in the accompanying drawings, identical components are indicated by the same reference numerals whenever possible. Furthermore, detailed descriptions of known functions and configurations that may obscure the essence of the present invention will be omitted. For the same reason, some components in the accompanying drawings may be exaggerated, omitted, or schematically depicted.

[0046]

[0047] FIG. 1 is a drawing showing a membrane manufacturing apparatus according to an embodiment of the present invention.

[0048] Referring to FIG. 1, a separator manufacturing device (10) according to an embodiment of the present invention may include a substrate supply unit (12), a coating unit (100), a drying unit (13), and a winding unit (14).

[0049] The substrate supply unit (12) is composed of a pair of rollers and supplies the separator substrate (11) by driving it into the coating unit (100). The separator substrate (11) may be, for example, manufactured using a polyolefin-based resin as the base resin or a nonwoven fabric, but is not particularly limited thereto.

[0050] Examples of polyolefin resins include polyethylene, polypropylene, and polypentene, and one or more of these may be included. A porous separator, that is, one having a large number of pores, manufactured using a polyolefin resin as a base resin, can provide a shutdown function at an appropriate temperature.

[0051] In addition to polyolefin-based nonwoven fabrics, the nonwoven fabric may be formed from polymers such as polyethyleneterephthalate, polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenyleneoxide, polyphenylenesulfide, polyethylenenaphthalene, etc., either individually or in a mixture thereof. The structure of the nonwoven fabric may be a spunbond nonwoven fabric or a melt-blown nonwoven fabric composed of long fibers.

[0052] The separator substrate may be formed by mixing different types of polyolefin resins or by forming a multilayer structure made of different types of polyolefin resins.

[0053] The weight-average molecular weight of the polyolefin resin may be 500,000 or more and 1,500,000 or less. By controlling the weight-average molecular weight of the polyolefin resin within the above-mentioned range, the compression resistance of the separator can be improved. Furthermore, when using a mixture of different types of polyolefin resins or forming a separator with a multilayer structure made of different types of polyolefin resins, the weight-average molecular weight of the polyolefin resin can be calculated by adding the weight-average molecular weights according to the content ratio of each polyolefin resin.

[0054] The coating portion (100) coats a coating layer on a separation membrane substrate (11), which is a porous polymer substrate. The coating layer may include inorganic particles and a binder.

[0055] The coating layer may include a plurality of pores. Specifically, the coating layer may be a porous coating layer. More specifically, the coating layer may be a porous coating layer containing a plurality of pores within it. As described above, by including a plurality of pores in the coating layer, it is possible to physically block the negative electrode and the positive electrode while allowing lithium ions to pass through and current to flow.

[0056] A coating layer can be formed by inorganic particles being bound by a binder and accumulated within the coating layer. Pores within the coating layer may originate from interstitial volumes, which are empty spaces between inorganic particles.

[0057] The thickness of the coating layer may be formed to a thickness of 1 μm to 20 μm on either side of the separator substrate, but is not specifically limited thereto. The thickness of the coating layer can be adjusted to an appropriate range by a person skilled in the art in terms of heat resistance or electrical resistance.

[0058] In the present invention, the coating portion (100) is configured such that the thickness of the coating layer (11a, see FIG. 2a and FIG. 2b) varies in the longitudinal direction, and this will be described later with reference to FIG. 2a and below. The separator substrate (11) and the coating layer (11a) constitute a separator.

[0059] The drying unit (13) can form a separation membrane by drying the solvent in the slurry contained in the coating layer coated in the coating unit (100). At this time, the method of drying the slurry for forming the coating layer is not particularly limited. For example, the coating layer formed on at least one surface of the separation membrane substrate (11) coated with the coating layer (11a) can be dried using a dryer such as an oven.

[0060] The winding unit (14) winds the separator dried in the drying unit (13). The winding unit can be applied without special limitations as long as it is a component commonly used in the industry and capable of winding the separator. The wound separator is stacked between the negative electrode and the positive electrode in a subsequent process to manufacture a secondary battery.

[0061]

[0062] FIGS. 2A and FIGS. 2B are cross-sectional views showing a coating portion (100) according to an embodiment of the present invention.

[0063] Referring to FIG. 2a, a coating portion (100) according to an embodiment of the present invention may include a coating liquid receiving portion (110) and a coating roller (200: 200_1 to 200_4, see FIG. 3 to 10). Optionally, a kiss roller (120) may be further included.

[0064] The coating liquid receiving portion (110) may be a housing that receives the separator coating liquid (111) inside and supplies the separator coating liquid, and the coating roller (200) may apply the separator coating liquid to the outer surface (specifically, the outer surface of the coating bar (201, see FIG. 3)) to form a coating layer (11a) by applying the coating liquid to at least one surface of the separator substrate (11).

[0065] Alternatively, referring to FIG. 2b, a discharge port (112) for discharging a membrane coating liquid (111) is formed at the top of the coating liquid receiving portion (110), and the membrane coating liquid can be continuously supplied to a coating roller (200) through the discharge port (112). The coating roller (200) is positioned adjacent to the discharge port (112) to apply the coating liquid to at least one surface of the membrane substrate (11) to form a coating layer (11a).

[0066] The coating roller (200) is configured to have a coating layer thickness that varies with a coating bar (201) with a controlled curvature.

[0067] Additionally, the kiss roller (120) is installed at the front and rear of the coating roller (200), respectively, and contacts the separator substrate (11) with low pressure, thereby pressing the separator substrate (11) in the direction of the coating roller (200), and assists the coating roller (200) in applying the coating liquid while suppressing vibrations caused by the curvature-adjusted coating bar (201).

[0068] In FIGS. 2a and 2b, the coating roller (200) is shown coating the lower surface of the separator substrate (11), but is not limited thereto. The coating roller (200) may be positioned on the upper and lower surfaces of the separator substrate (11) to coat both the upper and lower surfaces of the separator substrate (11).

[0069]

[0070] FIG. 3 is a perspective view showing a separator coating roller according to a first embodiment of the present invention, FIG. 4 is a cross-sectional view showing a separator coating roller according to a first embodiment of the present invention, and FIG. 5 is a view of the separator coating roller of FIG. 4 seen from right to left (direction A).

[0071] Referring to FIGS. 3 to 5, a separator coating roller (200_1) according to the first embodiment of the present invention may include a coating bar (201), a reference bearing (210), and a variable bearing part (220_1).

[0072] The coating bar (201) is a rod member formed extending in the width direction of the separator substrate (11), which is perpendicular to the driving direction of the separator substrate (11). The coating bar (201) is formed by penetrating the reference bearing (210) and the variable bearing (221).

[0073] The reference bearing (210) is formed to surround the outer surface of the coating bar (201). The reference bearing (210) is fixed to the outer surface of the coating bar (201) and may be provided as a pair on both sides of the coating bar (201). The reference bearing (210) may be formed on the inner side of the variable bearing portion (220_1).

[0074] The reference bearing (210) may include an inner ring (211) that directly surrounds the outer surface of the coating bar (201), an outer ring (212) that has a larger diameter than the inner ring (211) and is spaced apart by a predetermined distance, and a roller (213) disposed between the inner ring (211) and the outer ring (212).

[0075] The variable bearing section (220_1) can adjust the curvature of the coating bar (201) while varying the position of the variable bearing (221). Here, "curvature of the coating bar (201)" refers to the degree of bending of the coating bar (201). The degree of bending (i.e., curvature) of the coating bar (201) can be adjusted according to the change in the position of the variable bearing (221), using the reference bearing (210) as the bending reference.

[0076] Specifically, the variable bearing portion (220_1) may include a variable bearing (221), a bearing housing (222), an insertion hole (223), and an adjustment bolt (224). Optionally, the variable bearing (221) may further include an elastic buffer (221d) and a wear-resistant pad (221e).

[0077] The variable bearing (221) may include an inner ring (221a) that directly surrounds the outer surface of the coating bar (201), an outer ring (221b) that has a larger diameter than the inner ring (221a) and is spaced apart by a predetermined distance, and a roller (221c) disposed between the inner ring (221a) and the outer ring (221b), similar to the reference bearing (210).

[0078] The bearing housing (222) is formed in a cylindrical shape on both sides of the coating bar (201), and a hollow is formed inside, and a variable bearing (221) is placed in the hollow and an adjustment bolt (224) can move. The bearing housing (222) is connected to a rotary motor (not shown) and can be rotated by the rotary motor.

[0079] An insertion hole (223) may be formed in a recess on the outer surface of the bearing housing (222). The insertion hole (223) may penetrate from the outer surface of the bearing housing (222) to the hollow of the bearing housing (222). An adjustment bolt (224) is inserted into the insertion hole (223). The insertion depth of the adjustment bolt (224) can be adjusted by rotating it in one direction or the other.

[0080] A plurality of insertion holes (223) may be formed at equal intervals on the outer surface of the bearing housing (222). The insertion holes (223) may be formed in two or more pairs facing each other. An adjustment bolt inserted into one of the pairs of insertion holes fixes the variable bearing (221), and an adjustment bolt inserted into the other pair of insertion holes can adjust the position of the variable bearing (221).

[0081] Depending on the design, there may be only one insertion hole (223). This will be described later with reference to FIGS. 9 and FIGS. 10. In the first embodiment, the insertion holes (223) are formed in two pairs as an example.

[0082] The adjustment bolt (224) is inserted into the insertion hole (223), and the position of the variable bearing (221) can be adjusted by adjusting the insertion depth by tightening and loosening the multiple adjustment bolts (224).

[0083] In the case where there are four adjustment bolts (224), the upper and lower adjustment bolts (224) adjust the position of the variable bearing (221), and the left and right adjustment bolts (224) fix the left and right sides of the variable bearing (221) to firmly fix the variable bearing (221).

[0084] Referring to FIG. 5, the diameter of the threads of the plurality of adjustment bolts (224) may differ depending on their insertion positions. Specifically, the adjustment bolts inserted at the top and bottom are sufficient to vary the position of the variable bearing (221) by moving up and down, but the adjustment bolts inserted at the left and right sides must support a portion of the outer surface of the position-adjusted variable bearing (221). Therefore, the thread diameter (D1) of the adjustment bolts inserted at the left and right sides may be formed larger than the thread diameter (D2) of the adjustment bolts inserted at the top and bottom. Here, the thread diameter refers to the diameter of the body excluding the head at the top of the bolt.

[0085] Additionally, the length of the threads of the multiple adjustment bolts (224) may vary depending on their insertion positions. Since the adjustment bolts inserted at the top and bottom are intended to move the variable bearing (221) up and down to adjust the curvature of the coating bar (201), and the adjustment bolts inserted at the left and right are intended to support the outer surface of the variable bearing (221), the length of the adjustment bolts inserted at the top and bottom may be greater than that of the adjustment bolts inserted at the left and right.

[0086] Additionally, an elastic buffer (221d) may be formed annularly between the surface of the variable bearing (221) and the coating bar (201) to absorb friction caused by the coating bar (201) bending according to the position change of the variable bearing (221).

[0087] Additionally, a wear-prevention pad (221e) may be formed on the surface of the variable bearing (221) at the position in contact with the adjustment bolt (224) to prevent the surface of the variable bearing (221) from being worn or damaged by the adjustment bolt (224). In the following second to fourth embodiments, an elastic buffer (221d) and a wear-prevention pad (221e) may also be formed, but they are omitted from the illustration for convenience of explanation.

[0088]

[0089] Next, a separator coating roller according to a second embodiment of the present invention will be described with reference to FIG. 6. FIG. 6 is a drawing showing a separator coating roller according to a second embodiment of the present invention, which is another embodiment of the separator coating roller of FIG. 4 viewed from direction A.

[0090] Referring to FIG. 6, a separator coating roller (200_2) according to a second embodiment of the present invention may include a coating bar (201), a reference bearing (210, see FIG. 4), and a variable bearing part (220_2).

[0091] Since the coating bar (201) and the reference bearing (210) are substantially the same as those in the first embodiment described above, a repeated description is omitted.

[0092] The variable bearing part (220_2) may include a variable bearing (221), a bearing housing (222), an insertion hole (223), an adjustment bolt (224), and a side support member (225).

[0093] With respect to the variable bearing (221), bearing housing (222), insertion hole (223), and adjustment bolt (224), in this embodiment, only two adjustment bolts (224) are arranged vertically, so the only difference is that two insertion holes (223) are formed indented on the outer surface of the bearing housing (222), and the rest is substantially the same as the first embodiment described above.

[0094] The side support members (225) may be provided as a pair of plate members protruding oppositely from the hollow of the bearing housing (222). The pair of side support members (225) may be formed spaced apart by the diameter of the variable bearing (221).

[0095] A pair of side support members (225) can support both sides of the variable bearing (221) in place of the left and right adjustment bolts of the first embodiment, thereby limiting the variable bearing (221) from moving left and right.

[0096] The side support member (225) has a wider support surface than the adjustment bolt, so it can support both sides of the variable bearing (221) more firmly.

[0097]

[0098] Next, a separator coating roller according to a third embodiment of the present invention will be described with reference to FIGS. 7 and FIGS. 8. FIGS. 7 is a perspective view showing a separator coating roller according to a third embodiment of the present invention, and FIGS. 8 is a side view showing a separator coating roller according to a third embodiment of the present invention.

[0099] Referring to FIGS. 7 and 8, a separator coating roller (200_3) according to the third embodiment of the present invention may include a coating bar (201), a reference bearing (210), and a variable bearing part (220_3).

[0100] Since the coating bar (201) and the reference bearing (210) are substantially the same as those in the first embodiment described above, a repeated description is omitted.

[0101] The variable bearing part (220_3) may include a bearing housing (222), an insertion hole (223), an adjustment bolt (224), and a bearing guide (226).

[0102] With respect to the variable bearing (221), bearing housing (222), insertion hole (223), and adjustment bolt (224), in this embodiment, only two adjustment bolts (224) are arranged vertically, so the only difference is that two insertion holes (223) are formed indented on the outer surface of the bearing housing (222), and the rest is substantially the same as the first embodiment described above.

[0103] In this embodiment, the bearing housing (222) has an inner surface (222a), and a bearing guide (226) may be formed on the inner surface (222a) of the bearing housing (222). The inner surface (222a) may be a pair of opposing planes formed parallel to each other in the hollow of the bearing housing (222).

[0104] The spacing of a pair of opposing planes constituting the bearing guide (226) can be formed to be substantially the same as the diameter of the variable bearing (221).

[0105] The adjustment bolts (224) positioned above and below the variable bearing (221) adjust the position of the variable bearing (221), and the left and right movement of the variable bearing (221) can be restricted by the bearing guide (226). That is, the bearing guide (226) can replace the function of the left and right adjustment bolts (224) and more firmly support both sides of the variable bearing (221).

[0106]

[0107] Next, a separator coating roller according to a fourth embodiment of the present invention will be described with reference to FIGS. 9 and FIGS. 10. FIGS. 9 is a perspective view showing a separator coating roller according to a fourth embodiment of the present invention, and FIGS. 10 is a cross-sectional view showing a separator coating roller according to a fourth embodiment of the present invention.

[0108] Referring to FIGS. 9 and 10, a separator coating roller (200_4) according to the fourth embodiment of the present invention may include a coating bar (201), a reference bearing (210), and a variable bearing part (220_4).

[0109] Since the coating bar (201) and the reference bearing (210) are substantially the same as those in the first embodiment described above, a repeated description is omitted.

[0110] The variable bearing section (220) may include a variable bearing (221), a bearing housing (222), an insertion hole (223), an adjustment bolt (224), a bearing guide (226), and a compression spring (227). Depending on the design, a side support member (225) may replace the bearing guide (226).

[0111] With respect to the variable bearing (221), bearing housing (222), insertion hole (223), and adjustment bolt (224), in this embodiment, only one adjustment bolt (224) is placed on the upper or lower part of the coating bar (201), so the only difference is that one insertion hole (223) is formed in a recess on the outer surface of the bearing housing (222), and the rest is substantially the same as the first embodiment described above.

[0112] And, since the bearing guide (226) is substantially the same as the third embodiment described above and the side support member (225) is substantially the same as the second embodiment described above, a repeated description is omitted.

[0113] In this embodiment, one adjustment bolt (224) is inserted into the insertion hole (223), and the position of the variable bearing (221) can be adjusted by adjusting the insertion depth by tightening and loosening the one adjustment bolt (224). At this time, a compression spring (227) is installed to face the adjustment bolt (224), and when the one adjustment bolt (224) presses the variable bearing (221), a force is applied in the direction opposite to the direction of pressure, thereby firmly fixing the variable bearing (221).

[0114] Optionally, the insertion holes (223) may be provided as a pair of opposing holes, one adjustment bolt (224) may be inserted into the insertion hole (223), and a compression spring (227) may be inserted into the other insertion hole.

[0115] A single adjustment bolt (224) adjusts the position of the variable bearing (221), and a compression spring (227) firmly secures the position-adjusted variable bearing (221). Additionally, the left and right movement of the variable bearing (221) can be restricted by a side support member (225) or a bearing guide (226).

[0116]

[0117] Next, a separator coating roller according to a fifth embodiment of the present invention will be described with reference to FIGS. 11a to 11c. FIGS. 11a to 11c are cross-sectional views illustrating a separator coating roller according to a fifth embodiment of the present invention.

[0118] Referring to FIGS. 11a to 11c, a separator coating roller (200_5) according to the fifth embodiment of the present invention may include a coating bar (201), a reference bearing (210), and a variable bearing part (220: 220_1 to 220_4).

[0119] In this fifth embodiment, the variable bearing portion may be any one of the variable bearing portions of the first to fourth embodiments described above, and the curvature of the coating bar (201) may be adjusted according to the gap between the reference bearing (210) and the variable bearing portion (220: 220_1 to 220_4).

[0120] As shown in Fig. 11a, the preset reference distance between the reference bearing (210) and the variable bearing part (220) is denoted as X, and the length to which the coating bar (201) can be bent is denoted as Y.

[0121] As shown in FIG. 11b, when the reference bearing (210), which serves as the bending reference for the coating bar (201), is brought closer to the variable bearing part (220) and adjusted to a first gap (X1) smaller than the reference gap, the length (Y1) that the coating bar (201) can bend increases, so even if the variable bearing (221) is positioned to the same size, the coating bar (201) can be bent more significantly.

[0122] Conversely, as shown in FIG. 11c, if the reference bearing (210) is moved away from the variable bearing part (220) to adjust to a second gap (X2) larger than the reference gap, the length (Y2) that the coating bar (201) can bend is reduced, so even if the variable bearing (221) is positioned to the same size, the coating bar (201) can be bent less.

[0123] Furthermore, by making the movement interval of the variable bearing part (200) on one side and the variable bearing part (200) on the other side different, various curvatures can be implemented according to the working environment or the required quality of the separator.

[0124]

[0125] Next, the operation process of a separator coating roller according to embodiments of the present invention will be described with reference to FIGS. 12a to 15. Although the coating roller of the first embodiment is described as an example in FIGS. 12a to 15, the coating rollers of the second to fifth embodiments can also operate substantially the same way.

[0126] FIG. 12a shows the case where the variable bearing (221) is positioned in the center as a result of position adjustment by the adjustment bolt (224). At this time, as shown in FIG. 12b, the center line (L1) of the coating bar (201) is not bent at all, so the curvature is "0".

[0127] FIGS. 13a and 13b show a coating layer (11a) coated in the state of the coating bar (201) of FIGS. 12a and 12b. FIG. 13a is a plan view of the coating layer (11a) which is uniform in the longitudinal direction, and FIG. 13b is a side view of the coating layer (11a) which is formed with a uniform thickness of the coating layer (11a).

[0128] FIG. 14a shows the case where the variable bearing (221) is positioned upward as a result of position adjustment by the adjustment bolt (224). At this time, as shown in FIG. 14b, the centerline (L2) of the coating bar (201) is bent with a predetermined curvature.

[0129] FIG. 15 shows a coating layer (11a) coated in the state of the coating bar (201) of FIG. 14. FIG. 15 (a) is a plan view of the coating layer (11a) in which the thickness is not uniform and varies in the longitudinal direction. FIG. 15 (b) is a side view of the coating layer (11a), in which the coating layer (11a) becomes a thickness variation pattern formed by repeating the rotation cycle of the coating bar (201).

[0130] In some cases, when the coating bar (201) presses down on the separator substrate (11), a coating layer (11a) pattern may be formed on a pattern (11b) in which the thickness of the surface of the separator substrate (11) changes continuously, as shown in (c) of FIG. 15.

[0131] According to the separator coating roller (200: 200_1 ~ 200_5) and the separator manufacturing device (10) including the same according to the embodiments of the present invention as described above, pattern coating in which the thickness of the coating layer varies in the longitudinal direction is possible, thereby optimizing the performance of the secondary battery and maintaining safety.

[0132]

[0133] In the separation membrane coating roller according to the embodiments of the present invention, the rotational speed of the coating bar (201) can be determined according to the curvature of the coating bar (201).

[0134] For example, if the curvature of the coating bar (201) is large, vibrations caused by the rotation of the greatly curved coating bar (201) may occur significantly, so the rotational speed of the coating bar (201) may be a relatively small first speed. Conversely, if the curvature of the coating bar (201) is small, vibrations caused by the rotation of the slightly curved coating bar (201) may occur small, so the rotational speed of the coating bar (201) may be a second speed greater than the first speed. At this time, the rotational speed of the roller of the substrate supply unit (12) that supplies the separator substrate (11) in conjunction with the rotational speed of the coating bar (201) may also be varied. The relationship between the curvature of the coating bar (201) and the rotational speed of the coating bar (201) can be calculated using a statistical method based on repeated experiments.

[0135] Although embodiments of the present invention have been described above, those skilled in the art may modify and change the present invention in various ways by adding, changing, deleting, or adding components, etc., without departing from the spirit of the present invention as described in the claims, and such modifications and changes are also to be included within the scope of the rights of the present invention.

Claims

1. A coating bar forming a coating layer on a separator substrate; A reference bearing formed to surround the outer surface of the coating bar; and A separator coating roller comprising: a variable bearing portion positioned to surround the outer surface of the coating bar on the outside of the above-mentioned reference bearing, and capable of adjusting the curvature of the coating bar.

2. In Paragraph 1, The above variable bearing part A variable bearing positioned to surround the outer surface of the coating bar, a bearing housing having a hollow and an insertion hole formed penetrating from the outer surface to the hollow, and an adjustment bolt inserted into the insertion hole so as to be adjustable in insertion depth. A separator coating roller characterized in that the above variable bearing is positioned within the above hollow by the above adjustment bolt to adjust the curvature of the above coating bar.

3. In Paragraph 2, The above insertion holes are formed in two or more pairs facing each other, and A separator coating roller characterized in that, among the plurality of insertion hole pairs, the adjustment bolt inserted into the first insertion hole pair fixes the variable bearing, and the adjustment bolt inserted into the second insertion hole pair adjusts the position of the variable bearing.

4. In Paragraph 3, A separator coating roller characterized by the fact that the diameter of the threads of the above-mentioned adjusting bolt varies depending on the insertion position.

5. In Paragraph 3, A separator coating roller characterized by the above-mentioned adjustment bolt having different lengths depending on the insertion position.

6. In Paragraph 2, The above insertion holes are formed as a pair facing each other, and The variable bearing portion is provided with a pair of side support members that protrude opposite each other in the hollow to fix the variable bearing. A separator coating roller characterized by the adjustment bolt inserted into the above pair of insertion holes adjusting the position of the variable bearing.

7. In Paragraph 2, The above insertion holes are formed as a pair facing each other, and In the hollow of the bearing housing, bearing guides that are mutually opposing planes are formed so that the variable bearing can move only in a straight direction within the hollow, and A separator coating roller characterized by the adjustment bolt inserted into the above pair of insertion holes adjusting the position of the variable bearing.

8. In Paragraph 2, The above insertion holes are formed as a pair facing each other, and The adjustment bolt is inserted into one of the insertion holes to adjust the position of the variable bearing, and A separator coating roller characterized by having a compression spring facing the adjustment bolt inserted into the remaining insertion hole.

9. In Paragraph 2, The above variable bearing part The above insertion hole is one, and It comprises a compression spring installed to face the above-mentioned insertion hole, and a pair of side support members protruding to face each other in the hollow to fix the variable bearing, A separator coating roller characterized by a adjusting bolt inserted into the above-mentioned insertion hole that adjusts the position of the above-mentioned variable bearing.

10. In Paragraph 2, The above variable bearing part The above insertion hole is one, and It is equipped with a compression spring installed to face the above-mentioned insertion hole, and In the above-mentioned hollow, bearing guides that are mutually opposing planes are formed so that the variable bearing can move only in a straight direction within the above-mentioned hollow, and A separator coating roller characterized by the adjustment bolt inserted into the above-mentioned insertion hole adjusting the position of the above-mentioned variable bearing.

11. In Paragraph 2, A separator coating roller characterized by having an elastic buffer formed between the variable bearing and the outer surface of the coating bar to absorb friction caused by the coating bar bending according to the position change of the variable bearing.

12. In Paragraph 2, A separator coating roller characterized by having a wear-prevention pad formed at the location where the variable bearing and the adjustment bolt come into contact, which prevents the surface of the variable bearing from being worn or damaged by the adjustment bolt.

13. In Paragraph 2, A separator coating roller characterized by changing the curvature of the coating bar by changing the gap between the above-mentioned reference bearing and the above-mentioned variable bearing part.

14. In Paragraph 13, A separator coating roller characterized by bringing the reference bearing closer to the variable bearing section to adjust it to a first gap smaller than the reference gap so that the curvature of the coating bar increases, or moving the reference bearing away from the variable bearing section to adjust it to a second gap larger than the reference gap so that the curvature of the coating bar decreases.

15. A substrate supply unit that supplies a separator substrate; A coating liquid receiving portion for receiving a separation membrane coating liquid; and A coating roller that forms a coating layer on the separator substrate supplied from the above-mentioned substrate supply unit using a coating liquid contained in the coating liquid receiving unit; The above coating roller is, A coating bar positioned in the width direction of the above-mentioned separator substrate to apply a separator coating liquid to the separator substrate, and A reference bearing formed to surround the outer surface of the above-mentioned coating bar, and A separator manufacturing apparatus comprising a variable bearing part positioned to surround the outer surface of the coating bar on the outside of the above-mentioned reference bearing and capable of adjusting the curvature of the coating bar.

16. In Paragraph 15, The above variable bearing part A variable bearing positioned to surround the outer surface of the coating bar, a bearing housing having a hollow and an insertion hole formed penetrating from the outer surface to the hollow, and an adjustment bolt inserted into the insertion hole so as to be adjustable in insertion depth. A separator manufacturing apparatus characterized in that the above variable bearing is positioned within the above hollow by the above adjustment bolt to adjust the curvature of the above coating bar.

17. In Paragraph 15, A separator manufacturing apparatus characterized by further including kiss rollers installed at the front and rear of the coating roller, respectively, to press the separator substrate in the direction of the coating roller.

18. In Paragraph 15, A membrane manufacturing apparatus characterized by the rotational speed of the coating bar being determined according to the curvature of the coating bar.

19. In Paragraph 18, A separator manufacturing apparatus characterized by varying the roller rotation speed of the substrate supply unit in conjunction with the rotation speed of the coating bar.

20. In Paragraph 15, A separator manufacturing apparatus characterized in that the coating roller is positioned on the upper and lower sides of the separator substrate to form a coating layer on both the upper and lower sides of the separator substrate.

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