Coating apparatus and method for manufacturing a positive electrode

Abstract

To provide a coating apparatus that can shorten the manufacturing time of positive electrodes. [Solution] The coating apparatus comprises a conveyor roller 11 that continuously conveys a sheet-like material to be coated M, a first die head 12 that intermittently discharges a first slurry L1 toward a first surface region S1 of the continuously conveyed material to be coated M to intermittently form a first coated area, a second die head 14 that intermittently discharges a second slurry toward a second surface region S2 of the continuously conveyed material to be coated M to intermittently form a second coated area, and a third die head 16 that continuously discharges a third slurry toward a third surface region S3 of the continuously conveyed material to be coated M to continuously form a third coated area. The second surface region S2 is located downstream of the first surface region S1, and the third surface region S3 is located on both sides in the width direction of the conveyor roller 11 with respect to the first surface region S1 and the second surface region S2.

Description

Technical Field

[0005]

[0001] The present invention relates to a coating device and a method for manufacturing a positive electrode.

Background Art

[0002] In recent years, research and development have been carried out on batteries that contribute to energy efficiency in order to enable many people to access affordable, reliable, sustainable, and advanced energy.

[0003] The positive electrode constituting the battery has, for example, a positive electrode current collector, a positive electrode mixture layer disposed on the positive electrode current collector, and a frame-shaped insulating layer disposed around the positive electrode mixture layer.

[0004] Patent Document 1 describes a method for manufacturing a bicell of a battery. Here, the bicell has a reference plane and includes a first electrode formed to a specified thickness. Further, the periphery of the reference plane is defined by at least four side portions. Furthermore, the at least four side portions have a first side portion and a second side portion that are symmetric with respect to the center of the reference plane, and a third side portion and a fourth side portion that are symmetric with respect to the center of the reference plane. The method for manufacturing a bicell of a battery includes a step of adhering a first compensating member to the first side portion and the second side portion simultaneously or at different times, and a step of adhering a second compensating member to the third side portion and the fourth side portion simultaneously or at different times.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the method for manufacturing a battery bicell described in Patent Document 1, the step of bonding the first compensation member and the step of bonding the second compensation member are not performed consecutively, resulting in a longer manufacturing time for the battery bicell.

[0007] The present invention aims to provide a coating apparatus capable of shortening the manufacturing time of positive electrodes. [Means for solving the problem]

[0008] (1) A conveying unit for continuously conveying a sheet-like material to be coated; a first die head for intermittently discharging a first slurry toward a first surface region of the continuously conveyed material to be coated to intermittently form a first coated section; a first gas ejection unit for ejecting a first gas toward the end of the intermittently discharged first slurry; a second die head for intermittently discharging a second slurry toward a second surface region of the continuously conveyed material to be coated to intermittently form a second coated section; and a third die head for continuously discharging a third slurry toward a third surface region of the continuously conveyed material to be coated to continuously form a third coated section, wherein the first die head is positioned in a direction substantially perpendicular to the conveying direction of the material to be coated in the first surface region. A coating apparatus comprising: a die head that discharges the first slurry and has a slit-shaped first discharge port extending in the width direction of the conveying section; a second die head that discharges the second slurry in a direction substantially perpendicular to the conveying direction of the material to be coated in the second surface region and has a slit-shaped second discharge port extending in the width direction of the conveying section; the second surface region is located upstream or downstream of the first surface region and continuously forms the second coating section in an area where the first coating section has not been formed; and the third surface region is located on both sides in the width direction of the conveying section with respect to the first and second surface regions and forms the third coating section in an area where the first and second coating sections have not been formed.

[0009] (2) The first gas ejection unit ejects the first gas in a direction substantially parallel to the conveying direction of the material to be coated in the first surface region, and has a slit-shaped first ejection port extending in the width direction of the conveying unit, and a first main body and a second main body extending in the width direction of the conveying unit, The first nozzle is formed between the first main body and the second main body, The coating apparatus according to (1), wherein the first gas ejection unit is arranged such that the first ejection port is near the first discharge port, and the first main body and the second main body are arranged such that they are on the side of the first die head and the conveying unit, respectively, and the first main body extends further toward the first die head than the second main body.

[0010] (3) The coating apparatus according to (2), wherein the first gas ejection section further comprises a plurality of first supply ports to which the first gas is supplied, and a first gas confluence section connected to the plurality of first supply ports and the first ejection port, to which the first gas supplied from the plurality of first supply ports merges, and the plurality of first supply ports are arranged in the width direction of the conveying section.

[0011] (4) The coating apparatus according to (3), wherein the first supply port and the first gas confluence have dimensions larger than the first nozzle in the thickness direction, and the first gas confluence has an inclined surface that slopes toward the first nozzle.

[0012] (5) The coating apparatus according to (3) or (4), wherein the first main body has a groove-shaped portion extending in the width direction of the conveying section, the second main body is a plate-shaped member, and the first gas confluence portion is formed between the first main body and the second main body.

[0013] (6) The coating apparatus according to any one of (1) to (5), further comprising a second gas ejection section for ejecting a second gas toward the terminal end of the intermittently discharged second slurry, wherein the second gas ejection section ejects the second gas in a direction substantially parallel to the conveying direction of the material to be coated in the second surface region, and has a slit-shaped second nozzle extending in the width direction of the conveying section, and a third body section and a fourth body section extending in the width direction of the conveying section, the second nozzle being formed between the third body section and the fourth body section, the second gas ejection section being arranged such that the second nozzle is near the second discharge port, and the third body section and the fourth body section are on the side of the second die head and the conveying section, respectively, and the third body section extends further toward the second die head than the fourth body section.

[0014] (7) The coating apparatus according to any one of (1) to (6), wherein the first die head and the third die head coat the material to be coated at the same location in the conveying direction of the material to be coated.

[0015] (8) A method for manufacturing a positive electrode using a coating apparatus described in any one of (1) to (7), comprising the steps of: intermittently discharging the first slurry from the first die head toward a first surface region of the sheet-like material to be coated while continuously conveying the material to be coated, thereby intermittently forming a first coated portion; intermittently discharging the second slurry from the second die head toward a second surface region of the material to be coated, thereby intermittently forming a second coated portion; and continuously discharging the third slurry from the third die head toward a third surface region of the material to be coated, thereby continuously forming a third coated portion, wherein the material to be coated is a positive electrode current collector, the first slurry is a slurry for a positive electrode composite layer, and the second slurry and the third slurry are slurries for an insulating layer.

[0016] (9) The method for manufacturing a positive electrode according to (8), wherein the insulating material contained in the second slurry is the same as the insulating material contained in the third slurry.

[0017] (10) The method for manufacturing a positive electrode according to (8) or (9), further comprising a step of dividing a coated material on which the first coating section, the second coating section, and the third coating section are formed in a region where the second coating section is formed. [Advantages of the Invention]

[0018] According to the present invention, it is possible to provide a coating apparatus capable of shortening the manufacturing time of a positive electrode. [Brief Description of the Drawings]

[0019] [Figure 1] FIG. 1 is a perspective view showing a coating apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing the coating apparatus of FIG. 1. [Figure 3] FIG. 3 is a top view for explaining the first coating section. [Figure 4] FIG. 4 is a top view showing the dragging at the end portion of the first slurry. [Figure 5] FIG. 5 is an enlarged perspective view of the first air nozzle of FIG. 2. [Figure 6] FIG. 6 is an enlarged cross-sectional view of the first air nozzle of FIG. 2. [Figure 7] FIG. 7 is a cross-sectional view showing the coating apparatus of FIG. 1. [Figure 8] FIG. 8 is a top view for explaining the second coating section. [Figure 9] FIG. 9 is an enlarged cross-sectional view of the second air nozzle of FIG. 2. [Embodiments for Carrying Out the Invention]

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0021] [Coating Apparatus] As shown in Figures 1 and 2, the coating apparatus 10 includes a conveying roller 11 as a conveying unit for continuously conveying a sheet-like material to be coated M, and a first die head 12 that intermittently discharges a first slurry L1 toward a first surface region S1 of the continuously conveyed material to be coated M to intermittently form a first coated section C1 (see Figure 3). The coating apparatus 10 also includes a first air nozzle 13 as a first gas ejection unit that ejects a first gas A1 toward the terminal end of the intermittently discharged first slurry L1. As a result, drag at the terminal end of the first slurry L1 discharged from the first die head 12 is suppressed, and as a result, the shape accuracy of the first coated section C1 is improved. Here, the first die head 12 discharges the first slurry L1 in a direction substantially perpendicular to the conveying direction D1 of the material to be coated M in the first surface region S1. Furthermore, the first air nozzle 13 ejects the first gas A1 in a direction substantially parallel to the transport direction D1 of the material to be coated M in the first surface region S1.

[0022] In order to inject the first gas A1 toward the terminal end of the intermittently discharged first slurry L1, the timing of injecting the first gas A1 should be adjusted based on the coating speed of the first slurry L1 (convection speed of the material to be coated M), the flow velocity of the first gas A1, and the timing of stopping the discharge of the first slurry L1.

[0023] In this case, the coating speed of the first slurry L1 (conveying speed of the material to be coated M) is not particularly limited, but for example, it is 10 m / min or more and 60 m / min or less. Also, the ejection pressure of the first gas A1 is not particularly limited, but for example, it is 10 kPa or more and 700 kPa or less. Furthermore, the viscosity of the first slurry L1 at 25°C is not particularly limited, but for example, it is 1000 mPa·s or more and 3000 mPa·s or less.

[0024] Furthermore, if the first gas A1 is not injected towards the end of the intermittently discharged first slurry L1, drag will occur at the end of the first slurry L1 discharged from the first die head 12 (see Figure 4).

[0025] The first die head 12 discharges the first slurry L1 and has a slit-shaped first discharge port 12a that extends in the width direction W of the conveying roller 11 (material to be coated M). The first air nozzle 13 ejects the first gas A1 and has a slit-shaped first nozzle 13a that extends in the width direction W of the conveying roller 11 (see Figure 5). This further improves the shape accuracy of the first coated section C1. In this case, the first nozzle 13a is located near the first discharge port 12a. The width of the first nozzle 13a is not particularly limited, but for example, it is between 500 mm and 700 mm.

[0026] As shown in Figure 6, the first air nozzle 13 has a first body portion 61 and a second body portion 62 that extend in the width direction W of the conveying roller 11, and the first outlet 13a is formed between the first body portion 61 and the second body portion 62. At this time, the first body portion 61 and the second body portion 62 are arranged so as to be on the side of the first die head 12 and the conveying roller 11 (material to be coated M), respectively, and the first body portion 61 extends further toward the first die head 12 than the second body portion 62 (see Figure 2). Therefore, the first air nozzle 13 can be brought closer to the first discharge port 12a of the first die head 12 to efficiently eject the first gas A1. Furthermore, because the first body portion 61 extends further toward the first die head 12 than the second body portion 62, the first gas A1 is guided toward the end of the intermittently discharged first slurry L1, and the first air nozzle 13 does not interfere with the conveying roller 11.

[0027] The first air nozzle 13 further includes a plurality of first supply ports 63 into which the first gas A1 is supplied from a supply source (e.g., a tank), and a first gas confluence section 64 connected to the plurality of first supply ports 63 and the first outlet 13a, into which the first gas A1 supplied from the plurality of first supply ports 63 converges. In this case, the plurality of first supply ports 63 are formed in the width direction W (depth direction in the figure) of the conveyor roller 11.

[0028] The first supply port 63 and the first gas confluence 64 have dimensions larger than the first nozzle 13a in the thickness direction, and the first gas confluence 64 has an inclined surface I1 that slopes toward the first nozzle 13a. That is, the first main body 61 has a groove-shaped portion G1 that extends in the width direction W of the conveying roller 11, the second main body 62 is a plate-shaped member, and the first gas confluence 64 is formed between the first main body 61 and the second main body 62. In this case, the inclination angle of the inclined surface I1 is not particularly limited, but for example, it is 10° or more and 80° or less.

[0029] The first die head 12 is not particularly limited, and any known die head can be used as long as it is capable of intermittently discharging the first slurry L1 to intermittently form the first coated portion C1.

[0030] As shown in Figure 7, the coating apparatus 10 further includes a second die head 14 that intermittently discharges a second slurry L2 toward a second surface region S2 of the continuously conveyed material M to be coated, thereby intermittently forming a second coated section C2 (see Figure 8). In this case, the second surface region S2 is located downstream of the first surface region S1, and the second coated section C2 is formed in an area where the first coated section C1 has not been formed. As a result, the shape accuracy of the second coated section C2 is also high, along with the shape accuracy of the first coated section C1. Here, the second die head 14 discharges the second slurry L2 in a direction substantially perpendicular to the conveying direction D2 of the material M to be coated in the second surface region S2.

[0031] Furthermore, the coating apparatus 10 is further equipped with a second air nozzle 15, which serves as a second gas ejection unit that ejects a second gas A2 toward the terminal end of the intermittently discharged second slurry L2. As a result, drag at the terminal end of the second slurry L2 discharged from the second die head 14 is suppressed, and consequently, the shape accuracy of the second coated section C2 is improved. Here, the second air nozzle 15 ejects the second gas A2 in a direction substantially parallel to the transport direction D2 of the material to be coated M in the second surface region S2.

[0032] In order to inject the second gas A2 toward the terminal end of the intermittently discharged second slurry L2, the timing of injecting the second gas A2 should be adjusted based on the coating speed of the second slurry L2 (convection speed of the material to be coated M), the flow velocity of the second gas A2, and the timing of stopping the discharge of the second slurry L2.

[0033] In this case, the coating speed of the second slurry L2 (conveying speed of the material to be coated M) is not particularly limited, but for example, it is 10 m / min or more and 60 m / min or less. Also, the ejection pressure of the second gas A2 is not particularly limited, but for example, it is 10 kPa or more and 700 kPa or less. Furthermore, the viscosity of the second slurry L2 at 25°C is not particularly limited, but for example, it is 1000 mPa·s or more and 3000 mPa·s or less.

[0034] The second die head 14, like the first die head 12, discharges the second slurry L2 and has a slit-shaped second discharge port 14a that extends in the width direction W of the conveying roller 11. The second air nozzle 15, like the first air nozzle 13, ejects the second gas A2 and has a slit-shaped second nozzle 15a that extends in the width direction W of the material M to be coated. As a result, the shape accuracy of the second coated section C2 is further improved. In this case, the second nozzle 15a is located near the second discharge port 14a.

[0035] As shown in Figure 9, the second air nozzle 15 has a third body portion 71 and a fourth body portion 72 that extend in the width direction W of the conveying roller 11, and the second outlet 15a is formed between the third body portion 71 and the fourth body portion 72. At this time, the third body portion 71 and the fourth body portion 72 are positioned so as to be on the side of the second die head 14 and the conveying roller 11 (material to be coated M), respectively, and the third body portion 71 extends further toward the second die head 14 than the fourth body portion 72 (see Figure 7). Therefore, the second air nozzle 15 can be brought closer to the second discharge port 14a of the second die head 14 to efficiently eject the second gas A2. Furthermore, because the third body portion 71 extends further toward the second die head 14 than the fourth body portion 72, the second gas A2 is guided toward the end of the intermittently discharged second slurry L2, and the second air nozzle 15 does not interfere with the conveying roller 11.

[0036] The second air nozzle 15 further includes a plurality of second supply ports 73 into which the second gas A2 is supplied from a supply source (e.g., a tank), and a second gas confluence section 74 connected to the plurality of second supply ports 73 and the second outlet 15a, into which the second gas A2 supplied from the plurality of second supply ports 73 converges. In this case, the plurality of second supply ports 73 are formed in the width direction W (depth direction in the figure) of the conveyor roller 11.

[0037] The second supply port 73 and the second gas confluence section 74 have dimensions larger than the second nozzle 15a in the thickness direction, and the second gas confluence section 74 has an inclined surface I2 that slopes toward the second nozzle 15a. That is, the third main body 71 has a groove-shaped portion G2 that extends in the width direction W of the conveying roller 11, the fourth main body 72 is a plate-shaped member, and the second gas confluence section 74 is formed between the third main body 71 and the fourth main body 72. In this case, the inclination angle of the inclined surface I2 is not particularly limited, but for example, it is 10° or more and 80° or less.

[0038] The second die head 14 is not particularly limited, and any known die head can be used as long as it is capable of intermittently discharging the second slurry L2 to intermittently form the second coating portion C2.

[0039] As shown in Figure 1, the coating apparatus 10 further includes a third die head 16 that continuously discharges a third slurry toward a third surface region S3 of the continuously conveyed material M to be coated, thereby continuously forming a third coated section C3 (see Figure 8). At this time, the third surface region S3 exists on both sides of the width direction W of the conveying roller 11 with respect to the first surface region S1 and the second surface region S2, and the third coated section C3 is formed in the region where the first coated section C1 and the second coated section C2 have not been formed. As a result, when the first slurry is a slurry for the positive electrode composite layer, and the second and third slurries are slurries for the insulating layer, the third slurry is discharged at the same time as the first slurry (and second slurry), thus shortening the manufacturing time for the positive electrode. At this time, the second coated section C2 and the third coated section C3 form an insulating layer with high shape accuracy.

[0040] The third die head 16 is not particularly limited as long as it is capable of continuously discharging the third slurry and continuously forming the third coated portion C3, and any known die head can be used.

[0041] The order in which the first die head 12, the second die head 14, and the third die head 16 are arranged may be changed as needed. That is, the second surface region S2 may be located upstream of the first surface region S1.

[0042] Furthermore, the first die head 12 and the third die head 16 may be used to coat the material M at the same location in the conveying direction. That is, a known die head is used to intermittently discharge the first slurry and continuously discharge the third slurry.

[0043] [Coating method] The coating method of this embodiment includes a step of intermittently discharging a first slurry L1 from a first die head 12 toward a first surface region S1 of a sheet-like material to be coated M while continuously conveying the material, thereby intermittently forming a first coated portion C1, and can be carried out using a coating apparatus 10. At this time, a first gas A1 is ejected toward the terminal end of the intermittently discharged first slurry L1. As a result, drag at the terminal end of the first slurry L1 discharged from the first die head 12 is suppressed, and as a result, the shape accuracy of the first coated portion C1 is improved. Furthermore, the first slurry L1 is discharged in a direction substantially perpendicular to the conveying direction D1 of the material to be coated M in the first surface region S1, and the first gas A1 is ejected in a direction substantially parallel to the conveying direction D1 of the material to be coated M in the first surface region S1.

[0044] The coating method of this embodiment further includes a step of intermittently discharging a second slurry L2 from a second die head 14 toward a second surface region S2 of a continuously conveyed material M to be coated, thereby intermittently forming a second coated portion C2. At this time, the second surface region S2 is located downstream of the first surface region S1, and the second coated portion C2 is formed in an area where the first coated portion C1 has not been formed. As a result, the shape accuracy of the second coated portion C2 is also high, along with the shape accuracy of the first coated portion C1. Here, the second slurry L2 is discharged in a direction substantially perpendicular to the conveying direction D2 of the material M to be coated in the second surface region S2.

[0045] In this embodiment, the coating method may involve ejecting a second gas A2 toward the terminal end of the intermittently discharged second slurry L2. At this time, the second gas A2 is ejected in a direction substantially parallel to the transport direction D2 of the material to be coated M in the second surface region S2. As a result, drag at the terminal end of the second slurry L2 discharged from the second die head 14 is suppressed, and as a result, the shape accuracy of the second coated section C2 is improved. Here, the second gas A2 is ejected in a direction substantially parallel to the transport direction D2 of the material to be coated M in the second surface region S2.

[0046] The coating method of this embodiment further includes a step of continuously discharging a third slurry from a third die head 16 toward a third surface region S3 of a continuously conveyed material M to be coated to continuously form a third coated portion C3. At this time, the third surface region S3 exists on both sides in the width direction W of the conveying roller 11 with respect to the first surface region S1 and the second surface region S2, and the third coated portion C3 is formed in an area where the first coated portion C1 and the second coated portion C2 have not been formed. As a result, if the first slurry is a slurry for the positive electrode composite layer, and the second and third slurries are slurries for the insulating layer, the third slurry is also discharged at the same timing as the first slurry (and the second slurry). Therefore, if the first die head 12 and the third die head 16 coat at the same location in the conveying direction of the material M to be coated, the manufacturing time for the positive electrode is shortened. In this process, the third coated section C3 is coated continuously, and the second coated section C2 is coated intermittently perpendicular to the third coated section C3. As a result, a highly precise insulating layer is formed around the first coated section C1 by the second coated section C2 and the third coated section C3. If the third coated section C3 is also coated intermittently, gaps will be created, resulting in a lower precision in the shape of the insulating layer.

[0047] The coating method of this embodiment can also be used to coat both sides of the material to be coated M, and the first coated portion C1, the second coated portion C2, and the third coated portion C3 may be formed as a single unit on both sides. Furthermore, the coating method of this embodiment may further include a step of heating and drying the material to be coated M on which the first coated portion C1, the second coated portion C2, and the third coated portion C3 have been formed.

[0048] Furthermore, the coating method of this embodiment can be applied, for example, to the manufacture of the positive electrode that constitutes a battery.

[0049] [Manufacturing method for positive electrode] The positive electrode manufacturing method of this embodiment is a method of manufacturing a positive electrode by the coating method of this embodiment. Here, the material to be coated M is a positive electrode current collector, the first slurry is a slurry for the positive electrode composite layer, and the second and third slurries are slurries for the insulating layer. As a result, a positive electrode with high shape accuracy of the positive electrode composite layer and insulating layer can be obtained.

[0050] The positive electrode current collector is not particularly limited, but an example is aluminum foil.

[0051] The slurry for the cathode composite layer includes, for example, a cathode active material. The cathode active material is not particularly limited, but examples include ternary cathode material NCM and lithium iron phosphate.

[0052] The slurry for the insulating layer contains an insulating material. The insulating material is not particularly limited, but alumina is an example. In this case, the insulating materials contained in the second slurry and the third slurry may be different, but it is preferable that they be the same. This improves the durability of the insulating layer.

[0053] The method for manufacturing the positive electrode of this embodiment may further include a step of dividing the material to be coated M, on which the first coated portion C1, the second coated portion C2, and the third coated portion C3 are formed, in the region on which the second coated portion C2 is formed. The material to be coated M, on which the first coated portion C1, the second coated portion C2, and the third coated portion C3 are formed, is made into sheets, and a frame-shaped insulating layer is formed.

[0054] [Manufacturing method for solid-state batteries] The manufacturing method for the solid-state battery of this embodiment includes a step of obtaining a positive electrode using the positive electrode manufacturing method of this embodiment. Therefore, short circuits in the solid-state battery are suppressed.

[0055] The method for manufacturing a solid-state battery according to this embodiment may further include a step of forming a solid electrolyte layer on a positive electrode composite layer to form a positive electrode-solid electrolyte layer laminate.

[0056] Solid-state batteries are not particularly limited, but examples include all-solid-state lithium metal batteries. All-solid-state lithium metal batteries will be described below.

[0057] An all-solid-state lithium metal battery comprises a negative electrode having a negative electrode current collector and a lithium metal layer, a positive electrode having a positive electrode current collector and a positive electrode composite layer, and a solid electrolyte layer.

[0058] The negative electrode current collector is not particularly limited, but an example is copper foil.

[0059] The positive electrode composite layer contains a positive electrode active material and may further contain a solid electrolyte, a conductive additive, a binder, etc. The positive electrode active material is not particularly limited as long as it is capable of intercalating and releasing lithium ions, but examples include lithium nickel cobalt manganese composite oxide. The solid electrolyte is not particularly limited as long as it has lithium ion conductivity, but examples include oxide-based electrolytes and sulfide-based electrolytes. The conductive additive is not particularly limited as long as it has electronic conductivity, but examples include carbon black. The binder is not particularly limited as long as it can improve binding properties, but examples include styrene butadiene rubber.

[0060] The positive electrode current collector is not particularly limited, but an example is aluminum foil.

[0061] The solid electrolyte layer contains a solid electrolyte and may further contain a binder or the like. The solid electrolyte is not particularly limited as long as it has lithium ion conductivity, but examples include inorganic solid electrolytes such as oxide-based electrolytes and sulfide-based electrolytes. The binder is not particularly limited as long as it can improve the binding properties, but examples include styrene-butadiene rubber.

[0062] Furthermore, an intermediate layer having the function of uniformly depositing lithium metal may be formed between the negative electrode and the solid electrolyte layer. This stabilizes the interface between the intermediate layer and the solid electrolyte layer. In this case, the all-solid-state lithium metal battery may be an anode-free battery in which the lithium metal layer is not formed at the time of the first charge. In an anode-free battery, the lithium metal layer is formed after the first charge and discharge.

[0063] The intermediate layer contains a metal that can alloy with lithium and amorphous carbon, and may further contain a binder. The metal that can alloy with lithium and amorphous carbon are preferably nanoparticles. Examples of metals that can alloy with lithium include tin (Sn), silicon (Si), zinc (Zn), magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silver (Ag), aluminum (Al), bismuth (Bi), and antimony (Sb). Examples of amorphous carbon include carbon blacks such as acetylene black, furnace black, and Ketjen black, as well as coke and activated carbon. The amorphous carbon may be easily graphitizable carbon (soft carbon), difficult-to-graphitize carbon (hard carbon), CNT (carbon nanotube), fullerene, or graphene. The binder is not particularly limited as long as it can improve binding properties, but an example is polyvinylidene fluoride (PVDF).

[0064] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and the above embodiments may be modified as appropriate within the scope of the spirit of the present invention. [Explanation of Symbols]

[0065] 10 Coating equipment 11 Conveyor rollers 12. First Die Head 12a 1st outlet 13. First air nozzle 13a 1st spout 14. Second die head 14a 2nd outlet 15. Second air nozzle 15a 2nd spout 16. Third Die Head 61 First main body 62 Second Main Body 63 1st supply port 64 First Gas Confluence 71 Third Main Body 72 Fourth main body 73 2nd supply port 74 Second Gas Confluence A1 First Gas A2 Second Gas C1 First Coating Section C2 Second Coating Section D1, D2 Conveying direction G Groove I Inclined surface L1 First Slurry L2 Second Slurry M Covered material S1 1st surface area S2 2nd surface area S3 3rd surface area W (width direction)

Claims

1. A conveying unit that continuously transports sheet-like materials to be coated, A first die head intermittently discharges a first slurry toward the first surface region of the material to be coated, which is continuously conveyed, to intermittently form a first coated area. A first gas ejection unit that ejects a first gas toward the terminal end of the intermittently discharged first slurry, A second die head intermittently discharges a second slurry toward the second surface region of the material to be coated, which is continuously conveyed, to intermittently form a second coating section. The system includes a third die head that continuously discharges a third slurry toward the third surface region of the material to be coated, which is continuously transported, to continuously form a third coating section. The first die head discharges the first slurry in a direction substantially perpendicular to the conveying direction of the material to be coated in the first surface region, and has a slit-shaped first discharge port extending in the width direction of the conveying section. The second die head discharges the second slurry in a direction substantially perpendicular to the conveying direction of the material to be coated in the second surface region, and has a slit-shaped second discharge port extending in the width direction of the conveying section. The second surface region is located either upstream or downstream of the first surface region. The second coating portion is formed continuously in the region where the first coating portion is not formed. The third surface region is located on both sides in the width direction of the transport section with respect to the first surface region and the second surface region. A coating apparatus for forming the third coating portion in an area where the first coating portion and the second coating portion are not formed.

2. The first gas ejection unit ejects the first gas in a direction substantially parallel to the conveying direction of the material to be coated in the first surface region, and has a slit-shaped first nozzle extending in the width direction of the conveying unit, and a first main body and a second main body extending in the width direction of the conveying unit. The first nozzle is formed between the first main body and the second main body, The first gas ejection unit is arranged such that the first ejection port is near the first discharge port, and the first main body and the second main body are located on the side of the first die head and the conveying unit, respectively. The first main body extends further toward the first die head than the second main body. The coating apparatus according to claim 1.

3. The first gas ejection unit further comprises a plurality of first supply ports to which the first gas is supplied, and a first gas confluence unit connected to the plurality of first supply ports and the first ejection port, to which the first gas supplied from the plurality of first supply ports merges. The coating apparatus according to claim 2, wherein the plurality of first supply ports are arranged in the width direction of the conveying section.

4. The first supply port and the first gas confluence have dimensions larger than the first nozzle in the thickness direction. The coating apparatus according to claim 3, wherein the first gas confluence section has an inclined surface that slopes toward the first nozzle.

5. The first main body has a groove-shaped portion that extends in the width direction of the conveying section, The second main body is a plate-shaped member, The coating apparatus according to claim 3 or 4, wherein the first gas confluence is formed between the first main body and the second main body.

6. The system further includes a second gas ejection unit that ejects a second gas toward the terminal end of the intermittently discharged second slurry, The second gas ejection unit ejects the second gas in a direction substantially parallel to the conveying direction of the material to be coated in the second surface region, and has a slit-shaped second nozzle extending in the width direction of the conveying unit, and a third body part and a fourth body part extending in the width direction of the conveying unit. The second nozzle is formed between the third main body and the fourth main body, The second gas ejection unit is arranged such that the second ejection port is near the second discharge port, and the third and fourth main body units are positioned on the sides of the second die head and the conveying unit, respectively. The coating apparatus according to any one of claims 1 to 4, wherein the third main body extends further toward the second die head than the fourth main body.

7. The coating apparatus according to any one of claims 1 to 4, wherein the first die head and the third die head perform coating at the same location in the conveying direction of the material to be coated.

8. A method for manufacturing a positive electrode using a coating apparatus according to any one of claims 1 to 4, A step of continuously conveying the sheet-like material to be coated, and intermittently discharging the first slurry from the first die head toward the first surface region of the continuously conveyed material to be coated to intermittently form the first coated portion, A step of intermittently discharging the second slurry from the second die head toward the second surface region of the material to be coated which is being continuously conveyed, thereby intermittently forming the second coated portion, The process includes continuously discharging the third slurry from the third die head toward the third surface region of the continuously conveyed material to be coated to continuously form a third coated area, The material to be coated is a positive electrode current collector, The first slurry is a slurry for the positive electrode composite layer, A method for manufacturing a positive electrode, wherein the second slurry and the third slurry are slurries for an insulating layer.

9. The method for manufacturing a positive electrode according to claim 8, wherein the insulating material contained in the second slurry is the same as the insulating material contained in the third slurry.

10. A method for manufacturing a positive electrode according to claim 8, further comprising the step of dividing a material to be coated, on which the first coated portion, the second coated portion, and the third coated portion are formed, in the region on which the second coated portion is formed.

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