Slit coater, electrode plate of rechargeable battery, and ceramic insulator

Abstract

The invention discloses a slit coater, an electrode plate of a rechargeable battery, and a ceramic insulator. A slit coater includes: a lower die and an upper die coupled in an up-down direction, the lower die and the upper die forming a coated portion by applying an active material slurry on an electrode substrate, and discharging a ceramic insulating material to a boundary between the coated portion and an uncoated portion; and a spacer including an active material discharge portion between the lower mold and the upper mold and providing an active material discharge port discharging the active material slurry; and a ceramic material discharge portion providing a ceramic discharge port for discharging the ceramic insulating material; wherein the active material discharge port is at the center of the electrode substrate, the ceramic discharge ports are on both sides of the active material discharge port, and the ceramic discharge ports form a ceramic insulating layer by overlapping a ceramic insulating material on the coating portion at an end portion.

Description

Technical Field

[0001] Various embodiments relate to a slit coater, an electrode plate of a rechargeable battery, and a ceramic insulator. Background Art

[0002] Unlike primary batteries, rechargeable batteries are batteries that can be repeatedly charged and discharged. Small-capacity rechargeable batteries can be used in small portable electronic devices such as mobile phones, notebook computers, or camcorders, and large-capacity rechargeable batteries can be used as power sources for driving motors of hybrid vehicles and electric vehicles.

[0003] For example, a rechargeable battery may include an electrode assembly for charging and discharging, a bag containing the electrode assembly, and an electrode tab that electrically connects the electrode assembly and pulls it out of the bag. The electrode assembly may be a winding type in which a negative electrode plate and a positive electrode plate are wound together with a separator interposed therebetween, or may be a stacked type in which a negative electrode plate and a positive electrode plate are stacked together with a separator interposed therebetween. Summary of the invention

[0004] An embodiment can be implemented by providing a slit coater, which includes: a lower mold and an upper mold, which are arranged in an up-down direction and connected to each other, the lower mold and the upper mold are configured to form a coating portion by coating an active material slurry on an electrode substrate and discharge a ceramic insulating material to a boundary of the coated portion and an uncoated portion to form a ceramic insulating layer; and a spacer, including: an active material discharge portion between the lower mold and the upper mold, the active material discharge portion providing an active material discharge port configured to discharge the active material slurry, and a ceramic material discharge portion providing a ceramic discharge port configured to discharge the ceramic insulating material, wherein the active material discharge port is at the center of the electrode substrate in the width direction of the electrode substrate, the ceramic discharge port is on both sides of the active material discharge port in the width direction, and the ceramic discharge port is configured to form the ceramic insulating layer by overlapping the ceramic insulating material on the coating portion at both ends in the width direction.

[0005] The spacer may provide a first gap at the active material discharge port and a second gap at the ceramic discharge port, the second gap being smaller than the first gap.

[0006] The second gap may be located at a position greater than 1 / 2 of the height of the first gap.

[0007] The active material discharge port may be configured to discharge the active material slurry having passed through the cavity in the lower mold, and the ceramic discharge port may be configured to discharge the ceramic insulating material supplied to the spacer and having passed through the upper mold.

[0008] The spacer may include: a first supply channel on a side of the spacer facing the upper mold; a second supply channel connected to one end of the first supply channel through a first through hole and on a side of the spacer facing the lower mold; and a third supply channel connected to one end of the second supply channel through a second through hole and connected to the ceramic discharge port on the side of the spacer facing the upper mold.

[0009] A first width of the first supply channel may be equal to a second width of the second supply channel, and a third width of the third supply channel may be smaller than the first width and smaller than the second width.

[0010] The first through hole may be an elliptical hole, and the second through hole may be a polygonal hole narrowed toward the third supply channel.

[0011] The active material discharge port may be configured to form the coating portion in the width direction of the electrode substrate and an increased width portion having an increased width, the increased width combined with a width of the coating portion being greater than a width of the active material discharge port.

[0012] The ceramic discharge port may be on either side of the both sides of the active material discharge port and overlap the increased width portion, and be configured to discharge the ceramic insulating material having a width greater than the increased width of the increased width portion.

[0013] The upper mold and the lower mold may provide a plurality of active material discharge ports configured to form a plurality of coating portions on the electrode substrate, and the ceramic discharge port may be between the active material discharge ports and outside the active material discharge port on the outermost portion among the plurality of active material discharge ports.

[0014] Each embodiment can be implemented by providing an electrode plate of a rechargeable battery, the electrode plate comprising: a coating portion, the coating portion being formed by coating an active material on an electrode substrate; an uncoated portion; and a ceramic insulating layer, the ceramic insulating layer being formed by discharging a ceramic insulating material to a boundary of the coating portion and the uncoated portion, wherein the coating portion comprises an increased width portion having an increased width, the increased width together with the width of the coating portion being greater than the width of an active material discharge port of a slit coater, and the ceramic insulating layer having a width greater than the increased width of the increased width portion.

[0015] The ceramic insulating layer may be formed by the ceramic insulating material on the uncoated portion in the width direction of the electrode substrate, and on the upper surface of the end portion of the coated portion, the lower surface of the end portion of the coated portion, and the surface of the electrode substrate facing the lower surface of the end portion.

[0016] The ceramic insulating layer may include: a first insulator on the increased width portion; and a second insulator connected to the first insulator and overlapping the increased width portion.

[0017] The ceramic insulator may form a ceramic insulating layer at a boundary between a coating portion and a non-coating portion formed by coating an active material on an electrode substrate, and may include 84.89 wt % of Al 2 O 3 having a diameter D50 of 2.5 μm and 15.11 wt % of polyvinylidene fluoride (PVDF).

[0018] NMP (N-methylpyrrolidone) may be used as a solvent. The solid content of the slurry of the ceramic insulator may be 13 to 30 wt %. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various features will become apparent to those skilled in the art by describing in detail exemplary embodiments with reference to the accompanying drawings, in which:

[0020] Figure 1 A top view illustrating coating an active material slurry and a ceramic insulating material on an electrode substrate by using a slit coater according to an embodiment.

[0021] Figure 2 Show about Figure 1 Cross-sectional view along line II-II.

[0022] Figure 3 Show about Figure 1 Cross-sectional view along line III-III.

[0023] Figure 4 Show Figure 1 A top view of an overlapping portion of a coating portion formed of an active material slurry and a ceramic insulating layer formed of a ceramic insulating material.

[0024] Figure 5 Shown when viewed from above Figure 3 A perspective view of a spacer for discharging ceramic insulating material.

[0025] Figure 6 Shown when viewed from below Figure 3 A perspective view of a spacer for discharging ceramic insulating material.

[0026] Figure 7An image showing an electrode plate of a rechargeable battery according to an embodiment, the electrode plate being coated with an electrode substrate by using a slit coater according to an embodiment.

[0027] Figure 8 Show about Figure 7 Cross-sectional view along line VIII-VIII. DETAILED DESCRIPTION

[0028] Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.

[0029] In the drawings, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being "on" another layer or element, it can be directly on the other layer or element, or there may be intervening layers or elements. Additionally, it will be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or there may be one or more intervening layers. Like reference numerals refer to like elements throughout.

[0030] Figure 1 A top view showing coating of an active material slurry and a ceramic insulating material on an electrode substrate by using a slit coater according to an embodiment, Figure 2 Show about Figure 1 A cross-sectional view along line II-II of Figure 3 Show about Figure 1 Cross-sectional view along line III-III.

[0031] refer to Figures 1 to 3 The slit coater according to an embodiment may include a lower mold 10, an upper mold 20, and a spacer 30. In an implementation, the slit coater may coat the active material slurry onto the electrode substrate ES to form a plurality of columns of coating portions CP on the electrode substrate ES, and may coat a ceramic insulating material to form a ceramic insulating layer CIL.

[0032] In one embodiment, the slit coater may form three coating parts CP and six ceramic insulating layers CIL on one electrode substrate ES. The present disclosure may be applied to a slit coater that forms three or more / less coating parts on an electrode substrate, and the number of ceramic insulating layers may be set according to the number of coating parts.

[0033] The lower mold 10 and the upper mold 20 may be arranged in the up-down direction (e.g., in a vertically overlapping relationship), and may be combined or coupled to each other. The coupled lower mold 10 and upper mold 20 may coat the supplied active material slurry, which has passed through the cavity CB in the lower mold 10, the active material discharge portion 31 set by the spacer 30, and the active material discharge port 41, onto the electrode substrate ES. In one embodiment, the electrode substrate ES may be supported by or on the support roller BR, and may advance or move to form the coating portion CP.

[0034] The coupled lower mold 10 and upper mold 20 can discharge the ceramic insulating material (supplied from or supplied through or having passed through the upper mold 20) to the electrode substrate ES, the ceramic insulating material having passed through the ceramic material discharge portion 32 of the spacer 30 and the ceramic discharge port 42 (see Figure 4 In one embodiment, the electrode substrate ES may be supported by the support roll BR and may advance or move to form the ceramic insulating layer CIL. The ceramic insulating layer CIL may be at a boundary between the coated portion CP and the uncoated portion UCP.

[0035] In one embodiment, the spacer 30 may include an active material discharge portion 31 between the lower mold 10 and the upper mold 20, an active material discharge port 41 for discharging the active material slurry (having passed through the active material discharge portion 31), a ceramic material discharge portion 32 between the lower mold 10 and the upper mold 20, and a ceramic discharge port 42 for discharging the ceramic insulating material (having passed through the ceramic material discharge portion 32). For ease of description, Figure 1 The spacer 30 is shown, and the lower mold 10 and the upper mold 20 are omitted.

[0036] The spacer 30 may form a first gap G1 at the active material discharge port 41 provided or set by the lower mold 10, the upper mold 20, and the active material discharge portion 31, and may form a second gap G2 at the ceramic discharge port 42 set by the lower mold 10, the upper mold 20, and the ceramic material discharge portion 32. The second gap G2 may be inferior to or smaller than the first gap G1 (G2<G1).

[0037] The second gap G2 may be greater than 1 / 2 of the entire height of the first gap G1 ( Figure 2 and Figure 3 In the up-down direction in the second gap G2, for example, the bottom end of the second gap G2 may be higher than the center of the first gap G1 in the height direction or farther from the lower mold 10. In one embodiment, the ceramic discharge port 42 may be formed corresponding to a higher or upper position of the active material discharge port 41, so the ceramic insulating layer CIL may be formed by overlapping the ceramic insulating material on the coating portion CP (which has been formed of the active material slurry discharged from the active material discharge port 41).

[0038] In one embodiment, the slit coater according to one embodiment may form a coating portion CP on the electrode substrate ES, and may simultaneously form a ceramic insulating layer CIL at a boundary between the coating portion CP and the uncoated portion UCP. In one embodiment, the ceramic insulating material may be alumina or boehmite, and the particle diameter D50 may be at least 2.0 μm.

[0039] Figure 4 Show Figure 1 A top view of the overlapped portion of the coating formed by the active material slurry and the ceramic insulating layer formed by the ceramic insulating material. Figures 1 to 4 , referring to the active material discharge port 41 and the ceramic discharge port 42 , the active material discharge port 41 may be at the center of the electrode substrate ES in the width direction of the electrode substrate ES.

[0040] The ceramic discharge port 42 may be on both sides of the active material discharge port 41 in the width direction, and the ceramic insulating layer ClL may be formed by overlapping the ceramic insulating material on the coating portion CP at both ends in the width direction. In one embodiment, the ceramic discharge port 42 may be on both sides of one active material discharge port 41. In one embodiment, the active material discharge port 41 may include a plurality of active material discharge ports 41, and the ceramic discharge port 42 is between the plurality of active material discharge ports 41 and outside the active material discharge port on the outermost portion among the plurality of active material discharge ports 41.

[0041] The active material discharge port 41 may form a coating portion CP in the width direction of the electrode substrate ES, and the active material slurry may further form an increased width portion CP1 having a width ΔW. In one embodiment, for example, due to the fluidity of the material discharged from the active material discharge port 41, the coating portion CP and the increased width portion CP1 together may have a total width (W1+ΔW or W1+2ΔW (for example, if the increased width portion CP1 is on both sides of the coating portion CP)) greater than the width W1 of the active material discharge port 41.

[0042] In one embodiment, the coating portion CP may be formed of active material discharged from the active material discharge port 41 and may spread in the width direction to include an increased width portion CP1 having a width ΔW so that the total width ( W1 + ΔW) may be slightly greater than the width W1 of the active material discharge port 41 .

[0043] The ceramic discharge port 42 may be provided in close contact with or adjacent to either side of the active material discharge port 41, and may overlap or align with the increased width portion CP1. In one embodiment, a ceramic insulating material having a width W2 (greater than the width ΔW of the increased width portion CP1) may be discharged onto the increased width portion CP1 and the uncoated portion UCP.

[0044] In one embodiment, the ceramic discharge port 42 may correspond to or be aligned with the increased width portion CP1 and the uncoated portion UCP, and may discharge the ceramic insulating material to form a layer having a width W2 wider than the width ΔW of the increased width portion CP1, and may form a ceramic insulating layer CIL. In one embodiment, the ceramic insulating layer CIL may be formed on the increased width portion CP1 of the coating portion CP and on the uncoated portion UCP.

[0045] The ceramic insulating layer CIL may electrically insulate the increased width portion CP1 (at both ends in the width direction on the electrode substrate ES having the coating portion CP and the increased width portion CP1 thereon), thereby helping to prevent a short circuit between electrode plates of positive and negative electrodes in an electrode assembly including the electrode substrate ES.

[0046] The ceramic insulating layer CIL can help ensure stacking burr quality and short circuit stability, thereby enhancing process safety. In one embodiment, a rechargeable battery may include electrode plates of a negative electrode and a positive electrode manufactured in this manner, and a short circuit between the electrode plates of the negative electrode and the positive electrode can be effectively prevented, and electrical insulation performance can be enhanced.

[0047] Relative to the discharge direction (in Figure 4 In the embodiment, the ceramic discharge port 42 may be further back than the active material discharge port 41 by a distance D, for example, the opening of the ceramic discharge port 42 may be spaced apart from the opening of the active material discharge port 41 by the distance D. In one embodiment, after the coating portion CP and the increased width portion CP1 are formed by the active material discharged from the active material discharge port 41, the ceramic insulating material may be discharged from the ceramic discharge port 42.

[0048] In one embodiment, the ceramic insulating material of the ceramic insulating layer CIL may not be mixed with the increased width portion CP1 formed of the active material and may form a separate layer. In one embodiment, a short circuit between the electrode plates of the positive electrode and the negative electrode may be more effectively prevented, and electrical insulation performance may be further enhanced.

[0049] Figure 5 Shown when viewed from above Figure 3 A perspective view of a spacer for discharging ceramic insulating material, and Figure 6 Shown when looking from the bottom Figure 3A perspective view of a spacer for discharging porcelain insulating material. Figure 3 , Figure 5 and Figure 6 , the spacer 30 may include a first supply channel 311 , a second supply channel 312 , a third supply channel 313 , a first through hole 321 , and a second through hole 322 .

[0050] The first supply channel 311 may be at a side of the spacer 30 facing the upper mold 20, may be set together with the lower surface of the upper mold 20, and the supplied ceramic insulating material may first pass through the first supply channel 311. The upper end of the first through hole 321 may be connected to one end of the first supply channel 311 or be fluidly connected to one end of the first supply channel 311 to provide a path for moving the ceramic insulating material (from the side of the spacer 30 facing the upper mold 20) to the side of the spacer 30 facing the lower mold 10.

[0051] The second supply channel 312 may be in fluid communication with the lower end of the first through hole 321, may be on the side of the spacer 30 facing the lower mold 10, and may be set together with the upper surface of the lower mold 10, and the ceramic insulating material having passed through the first supply channel 311 and the first through hole 321 may pass through the second supply channel 312. The lower end of the second through hole 322 may be in fluid communication with one end of the second supply channel 312, and may provide a path for moving the ceramic insulating material from the side of the spacer 30 facing the lower mold 10 to the side of the spacer 30 facing the upper mold 20.

[0052] The third supply channel 313 may be in fluid communication with the upper end of the second through hole 322 and may be set together with the lower surface of the upper mold 20, and the ceramic insulating material (having passed through the second supply channel 312 and the second through hole 322) may pass through the third supply channel 313. The third supply channel 313 may be in fluid communication with the ceramic discharge port 42 on the side of the spacer 30 facing the upper mold 20, and may help form the ceramic insulating layer CIL having a width W2.

[0053] The first width W11 of the first supply channel 311 and the second width W12 of the second supply channel 312 may be the same, and the third width W13 of the third supply channel 313 may be smaller than each of the second width W12 and the first width W11. In one embodiment, the first through hole 321 may be an elliptical hole, and the second through hole 322 may be a polygonal hole that narrows along one side adjacent to the third supply channel 313.

[0054] In one embodiment, the ceramic insulating material may pass through the first supply channel 311, the first through hole 321, the second supply channel 312, the second through hole 322 and the third supply channel 313 in sequence, may be narrowed from the first width W11 and the second width W12 to the third width W13, may pass through the ceramic discharge port 42 (for example, while being pressurized), and may be supplied.

[0055] Figure 7 An image showing an electrode plate of a rechargeable battery according to an embodiment, the electrode plate being coated on an electrode substrate by using a slit coater according to an embodiment, and Figure 8 Show about Figure 7 Cross-sectional view along line VIII-VIII.

[0056] refer to Figure 7 and Figure 8 , the ceramic insulating layer CIL formed by the ceramic insulating material supplied to the slit coater according to one embodiment may be on the uncoated portion UCP in the width direction, and may be formed by the ceramic insulating material supplied to the upper surface of the end portion of the coating portion CP, the lower surface of the end portion of the coating portion CP facing each other, and the space on the surface of the electrode substrate ES.

[0057] Regarding the electrode plate of a rechargeable battery according to an embodiment, the coating portion CP may further include an increased width portion CP1 having a width ΔW extending beyond a width W1 of the active material slurry discharged from the active material discharge port 41 of the slit coater. In an embodiment, the active material slurry may receive resistance due to friction with the uncoated portion UCP at an end portion of the coating portion CP, and may form the increased width portion CP1 convex to one side due to its cohesive force.

[0058] The ceramic insulating layer CIL may be formed on the uncoated portion UCP to have a width W2 greater than the increased width ΔW of the increased width portion CP1. The ceramic insulating layer CIL may include a first insulator or a first overlapping portion OP1 on the upper surface of the increased width portion CP1 and a second insulator or a second overlapping portion OP2 in a space between the lower surface of the increased width portion CP1 and the surface of the electrode substrate ES, and the first overlapping portion OP1 and the second overlapping portion OP2 may be connected to the uncoated portion UCP. In one embodiment, a ceramic insulating material may be supplied when forming the increased width portion CP1, so that the first overlapping portion OP1 and the second overlapping portion OP2 may be formed in a height direction with the increased width portion CP1 located therebetween.

[0059] The first overlapping portion OP1 and the second overlapping portion OP2 may not allow the ceramic insulating material of the ceramic insulating layer CIL to mix with the increased width portion CP1 formed of the active material, but may form an additional layer. In one embodiment, in a rechargeable battery, the electrode plates (of the positive electrode and the negative electrode) having the increased width portion CP1 and the ceramic insulating layer CIL (including the first overlapping portion OP1 and the second overlapping portion OP2) may more effectively prevent a short circuit from occurring therebetween, and thereby enhance electrical insulation performance.

[0060] Referring to Table 1, the ceramic insulator used to form the ceramic insulating layer CIL may include 84.89wt% of Al2O3 having a diameter D50 of 2.5μm and 15.11wt% of PVDF. NMP (N-methylpyrrolidone) may be used as a solvent, and a very small amount of additive (G-NMP) may be used. The solid content in the slurry of the ceramic insulator may be 13 to 30wt%. The ceramic may be aluminum or boehmite. The binder PVDF may include 14.29wt% of S6020 and 0.82wt% of S5130.

[0061] The ceramic insulator according to the comparative example may include 92.8wt% of Al2O3 having a diameter D50 of 1.2μm and 7.2wt% of PVDF. NMP (N-methylpyrrolidone) may be used as a solvent, and a very small amount of additive (G-NMP) may be used. The solid content in the slurry of the ceramic insulator may be 10wt%. The binder PVDF may include 7.02wt% of S6020 and 0.18wt% of S5130.

[0062] Table 1

[0063]

[0064] When a ceramic insulating layer is formed by applying a spacer 30 according to an embodiment, the ceramic insulator according to the first comparative example and the second comparative example forms a ceramic insulating layer having a width W2 of 2 mm to 2.7 mm, a thickness of 75±3 μm to 100±3 μm, an overlapping width ΔW of 0.5 mm and a solid content of 10 wt %.

[0065] The ceramic insulators according to the first and second comparative examples formed the ceramic insulating layer with a thickness equal to or greater than 60 μm, and thus did not form a suitable sum of both-side thicknesses.

[0066] When a ceramic insulating layer is formed by applying a spacer 30 according to one embodiment, the ceramic insulator according to the first to sixth embodiments forms a ceramic insulating layer having a width W2 of 2.8 mm to 6.0 mm, a thickness of 20±3 μm to 55±3 μm, an overlapping width ΔW of 0.5 mm to 0.8 mm and a solid content of 13 to 30 wt %.

[0067] The first to sixth embodiments form a ceramic insulating layer having a thickness equal to or less than 55 mm and 40 mm, thereby forming a suitable sum of thicknesses on both sides. That is, when the spacer 30 according to one embodiment and the ceramic insulator according to the first to sixth embodiments are used, the ceramic insulating layer can be stably formed on the increased width portion CP1, and the first overlapping portion OP1 and the second overlapping portion OP2 can be stably formed.

[0068] By way of summary and review, the electrode plates of a rechargeable battery may have a risk factor for combustion, which may be caused by burr generation of the electrode substrate and possible short circuits between the electrode plates of the positive and negative electrodes. Electrical insulation on the electrode plates of the positive and negative electrodes may be used to help improve the safety of the rechargeable battery and its performance.

[0069] One or more embodiments may provide a slit coater for coating an active material slurry on an electrode substrate of a rechargeable battery.

[0070] One or more embodiments may provide a slit coater for forming a coating portion with an active material slurry to help prevent a short circuit between electrode plates of a negative electrode and a positive electrode, and for forming a ceramic insulating layer with a ceramic insulating material.

[0071] The slit coater according to an embodiment may include an active material discharge port at the center of the electrode substrate in the width direction of the electrode substrate, and may include ceramic discharge ports on both sides of the active material discharge port in the width direction to overlap the ceramic insulating layer and the coating portion at both ends in the width direction. Therefore, the electrode plate of the negative electrode and the positive electrode having the ceramic insulating layer can help effectively prevent a short circuit between the negative electrode and the positive electrode in the rechargeable battery.

[0072] The present disclosure is also directed to providing a ceramic insulator for forming a ceramic insulating layer using a slit coater.

[0073] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and interpreted in a general and descriptive sense only, and not for purposes of limitation. In some cases, as will be apparent to one of ordinary skill in the art at the time of filing this application, unless specifically indicated otherwise, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the claims.

Claims

1. A slit coating machine, comprising: A lower die and an upper die are arranged in the up-down direction and connected to each other, and the lower die and the upper die are configured to: forming a coating portion by coating an active material slurry on an electrode substrate, and discharging a ceramic insulating material to a boundary of the coated portion and the uncoated portion to form a ceramic insulating layer; as well as Spacers, including: an active material discharge portion between the lower mold and the upper mold, the active material discharge portion providing an active material discharge port configured to discharge the active material slurry, and a ceramic material discharge portion, providing a ceramic discharge port configured to discharge the ceramic insulating material, in: The active material discharge port is at the center of the electrode substrate in the width direction of the electrode substrate, and the ceramic discharge ports are at both sides of the active material discharge port in the width direction, and The ceramic discharge port is configured to form the ceramic insulating layer by overlapping the ceramic insulating material on the coating portion at both ends in the width direction.

2. The slot coater of claim 1, wherein the spacer provides: a first gap at the active material discharge port, and A second gap is provided at the ceramic discharge port, wherein the second gap is smaller than the first gap. 3 . The slit coater according to claim 2 , wherein the second gap is located at a position greater than 1 / 2 of the height of the first gap.

4. The slit coater according to claim 1, wherein: The active material discharge port is configured to discharge the active material slurry having passed through the cavity in the lower mold, and The ceramic discharge port is configured to discharge the ceramic insulating material supplied to the spacer and having passed through the upper mold.

5. The slot coater according to claim 4, wherein the spacer comprises: a first supply channel, on a side of the spacer facing the upper mold, a second supply channel connected to one end of the first supply channel through a first through hole and on a side of the spacer facing the lower mold, and A third supply channel is connected to one end of the second supply channel through a second through hole and is connected to the ceramic discharge port at the side of the spacer facing the upper mold.

6. The slit coater according to claim 5, wherein: A first width of the first supply channel is equal to a second width of the second supply channel, and A third width of the third supply channel is smaller than the first width and smaller than the second width.

7. The slit coater according to claim 5 or 6, wherein: The first through hole is an elliptical hole, and The second through hole is a polygonal hole that narrows toward the third supply channel.

8. The slit coater according to claim 1, wherein the active material discharge port is configured to form: The coating portion is in the width direction of the electrode substrate, and The increased width portion has an increased width, the increased width combined with the width of the coating portion being greater than the width of the active material discharge port.

9. The slot coater according to claim 8, wherein the ceramic discharge port: on either side of the two sides of the active material discharge port and overlapping with the increased width portion, and The device is configured to discharge the ceramic insulating material, the ceramic insulating material having a width greater than the increased width of the increased width portion.

10. The slot coater according to claim 1, wherein: The upper mold and the lower mold provide a plurality of active material discharge ports configured to form a plurality of coating portions on the electrode substrate, and The ceramic discharge port is between the plurality of active material discharge ports and outside an active material discharge port at an outermost portion among the plurality of active material discharge ports.

11. An electrode plate for a rechargeable battery, comprising: a coating portion formed by coating an active material on an electrode substrate; Uncoated part; as well as a ceramic insulating layer formed by discharging a ceramic insulating material to a boundary between the coated portion and the uncoated portion, in: The coating portion includes an increased width portion having an increased width, the increased width combined with a width of the coating portion being greater than a width of an active material discharge port of a slit coater, and The ceramic insulating layer has a width greater than the increased width of the increased width portion.

12. The electrode plate according to claim 11, wherein the ceramic insulating layer: is formed by the ceramic insulating material on the uncoated portion in the width direction of the electrode substrate, and On an upper surface of an end portion of the coating portion, a lower surface of the end portion of the coating portion, and a surface of the electrode substrate facing the lower surface of the end portion.

13. The electrode plate according to claim 11, wherein the ceramic insulating layer comprises: a first insulator on the increased width portion, and A second insulator is connected to the first insulator and overlaps the increased width portion.

14. A ceramic insulator, wherein the ceramic insulating layer is formed at a boundary between a coating portion and an uncoating portion formed by coating an active material on an electrode substrate, and comprises 84.89 wt % of Al2O3 having a diameter D50 of 2.5 μm and 15.11 wt % of polyvinylidene fluoride.

15. The ceramic insulator according to claim 14, wherein N-Methylpyrrolidone was used as a solvent.

16. The ceramic insulator according to claim 14, wherein The solid content of the slurry of the ceramic insulator is 13-30 wt %.

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