Slit mold coating machine and polar plate manufactured by same

Abstract

The invention provides a slit mold coating machine and a pole plate manufactured by the slit mold coating machine. The slit mold coating machine includes: a slit mold configured to include a first slit through which a first active material is dispensed, a second slit through which a second active material is dispensed, and a third slit through which a third active material is dispensed; and a first spacer, a second spacer, and a third spacer inserted into the first, second, and third slits, respectively, in which the first, second, and third slits are sequentially aligned in a traveling direction in which the substrate moves, to form an active material coating layer having a plurality of layers, the active material dispensed by the first, second, and third spacers is stacked in the plurality of layers.

Description

Technical Field

[0001] Aspects of the present disclosure relate to a slot die coater and a plate electrode manufactured by the slot die coater. Background Art

[0002] Unlike primary batteries that are not designed to be (re)charged, secondary (or rechargeable) batteries are designed to be discharged and recharged. Low-capacity secondary batteries are used in portable small electronic devices such as smart phones, feature phones, laptop computers, digital cameras, and video cameras, while high-capacity secondary batteries are widely used as power sources for driving motors in hybrid vehicles and electric vehicles and for storing electric power (e.g., home and / or utility-scale power storage). A secondary battery generally includes an electrode assembly composed of a positive electrode and a negative electrode, a case accommodating the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] A negative electrode plate of a secondary battery is manufactured by applying a negative electrode active material layer on the surface of a substrate and then drying the resulting structure. The negative electrode active material included in the negative electrode active material layer may include a carbon-based negative electrode active material, a silicon-based negative electrode active material, or a combination thereof. The carbon-based negative electrode active material has the advantage of higher stability than the silicon-based negative electrode active material, but has the problem of smaller energy storage capacity than the silicon-based negative electrode active material.

[0004] Therefore, from the perspective of increasing battery capacity, it is desirable to increase the content of the silicon-based negative electrode active material. However, in examples where the content of the silicon-based negative electrode active material is increased, there is a problem of reduced battery life due to volume expansion of the silicon-based negative electrode active material.

[0005] The above information disclosed in this background art section is for enhancing understanding of the background art of the present disclosure. Therefore, it may include information that does not constitute related (or prior) art. Summary of the Invention

[0006] Aspects of the present disclosure relate to a manufacturing apparatus for manufacturing plate electrodes for secondary batteries in a continuous process to extend battery life by reducing volume expansion, and to plate electrodes manufactured by the manufacturing apparatus.

[0007] These and other aspects and features of the present disclosure will be described in the following description of embodiments of the present disclosure or will be apparent from the following description of embodiments of the present disclosure.

[0008] According to some embodiments of the present disclosure, a slot die coater is provided, including: a slot die configured to include a first slot, a second slot, and a third slot, through which a first active material, a second active material, and a third active material are respectively dispensed; and a first spacer, a second spacer, and a third spacer respectively inserted into the first, second, and third slots, wherein the first, second, and third slots are sequentially aligned in the traveling direction of the substrate movement to form an active material coating layer having multiple layers, and the active materials dispensed through the first, second, and third spacers are stacked in the multiple layers.

[0009] In some embodiments, the content of the carbon-based material in each of the first active material and the third active material is greater than that in the second active material, and the content of the silicon-based material in each of the first active material and the third active material is less than that in the second active material.

[0010] In some embodiments, the third spacer includes a first third spacer and a second third spacer aligned to contact the first third spacer, and the first third spacer and the second third spacer have different shapes.

[0011] In some embodiments, the thickness of the first third spacer is equal to the thickness of the second third spacer.

[0012] In some embodiments, each of the first spacer and the second third spacer has an opening provided as a cutout in its area to determine the width of the active material coated on the substrate.

[0013] In some embodiments, each of the second spacer and the first third spacer includes a slit portion having a plurality of slits to determine the width of the active material coated on the substrate, and an active material coating layer having a strip pattern is formed through the slit portion.

[0014] In some embodiments, the slit portion of the first spacer is configured such that slits and a plurality of teeth are alternately repeated, wherein each slit has a first width and each tooth has a second width, and the slit portion of the second spacer is configured such that slits and a plurality of teeth are alternately repeated, wherein each slit has a second width and each tooth has a first width.

[0015] In some embodiments, the slits in the second spacer and the slits in the first spacer are arranged to be staggered with respect to each other.

[0016] In some embodiments, the first width is longer than the second width.

[0017] In some embodiments, the length of the teeth in the first and third spacers is shorter than the length of the teeth in the second spacer by a set length, such that the distal ends of the teeth provided in the first and third spacers are aligned to be inwardly formed by the set length compared to the distal ends of the teeth in the second spacer.

[0018] In some embodiments, a first coated portion coated with a second active material with a second width and an uncoated portion not coated with the second active material are alternately arranged using the second spacer, and a second coated portion coated with a third active material with the second width and a third coated portion coated with the third active material with a first width are alternately arranged on top of the first coated portion and the uncoated portion using the first and third spacers and the second and third spacers.

[0019] In some embodiments, the thickness of the first coated portion corresponds to the thickness of the second coated portion, and the thickness of the third coated portion is different from the thickness of the first coated portion and the thickness of the second coated portion.

[0020] In some embodiments, the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 1 and 3.

[0021] In some embodiments, the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 1.9 and 2.1.

[0022] In some embodiments, the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 3 and 4.

[0023] In some embodiments, the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 3.2 and 3.4.

[0024] In some embodiments, the set length is 4 mm or less.

[0025] In some embodiments, the set length is 2 mm or less.

[0026] According to some embodiments of the present disclosure, a plate electrode is provided, including: a substrate; and a first active material layer, a second active material layer, and a third active material layer configured to coat the surface of the substrate, wherein the first active material layer is coated with a first active material, wherein the third active material layer is coated with a third active material, and wherein the second active material layer is coated with the third active material and the second active material alternately arranged in the width direction of the substrate.

[0027] In some embodiments, the content of the carbon-based material in each of the first active material and the third active material is greater than the content of the carbon-based material in the second active material, and

[0028] The content of the silicon-based material in each of the first active material and the third active material is less than the content of the silicon-based material in the second active material.

[0029] However, aspects and features of the present disclosure are not limited to those described above, and other aspects and features not mentioned will be clearly understood by those skilled in the art from the detailed description described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The following drawings attached to this specification illustrate embodiments of the present disclosure and further describe aspects and features of the present disclosure together with the detailed description of the present disclosure. Therefore, the present disclosure should not be construed as being limited to the drawings:

[0031] Figure 1 An example of a secondary battery according to some embodiments of the present disclosure is shown.

[0032] Figures 2 to 5 A comparative example of an electrode plate according to some embodiments of the present disclosure is shown.

[0033] Figure 6 The configuration of a slot die coater according to some embodiments of the present disclosure is shown.

[0034] Figure 7 Examples of a first separator and second and third separators according to some embodiments of the present disclosure are shown.

[0035] Figure 8 An example of a second separator according to some embodiments of the present disclosure is shown.

[0036] Figure 9 An example of a first and third separator according to some embodiments of the present disclosure is shown.

[0037] Figure 10 An example of coating a substrate using a first separator and second and third separators according to some embodiments of the present disclosure is shown.

[0038] Figure 11 A cross-sectional view showing a plate according to some embodiments of the present disclosure is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Terms or words used in this specification and claims should not be construed as being limited to the ordinary or dictionary meanings, and should be interpreted as meanings and concepts consistent with the technical idea of the present disclosure based on the principle that the inventor can be his / her own lexicographer to appropriately define terms so as to best explain his / her invention.

[0040] The embodiments described in this specification and the configurations shown in the drawings are only some embodiments of the present disclosure and do not represent all the technical ideas, aspects, and features of the present disclosure. Therefore, it should be understood that there may be various equivalents and modifications that can replace or modify the embodiments described herein when this application is filed.

[0041] It should be understood that when an element or layer is referred to as being "on", "connected to", or "coupled to" another element or layer, it can be directly on, directly connected to, or directly coupled to the other element or layer, or there may also be one or more intermediate elements or layers. When an element or layer is referred to as being "directly on", "directly connected to", or "directly coupled to" another element or layer, there are no intermediate elements or layers. For example, when a first element is described as being "coupled" or "connected" to a second element, the first element can be directly coupled or connected to the second element, or the first element can be indirectly coupled or connected to the second element via one or more intermediate elements.

[0042] In the drawings, for clarity of illustration, the dimensions of various elements, layers, etc. may be exaggerated. The same reference numerals denote the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Further, when describing embodiments of the present disclosure, the use of "may" relates to "one or more embodiments of the present disclosure". Expressions such as "at least one of..." and "any one of..." modify the entire list of elements when preceding the list of elements, rather than individual elements in the list. When phrases such as "at least one of A, B, and C", "at least one of A, B, or C", "at least one selected from the group consisting of A, B, and C", or "at least one selected from A, B, and C" are used to specify a list of elements A, B, and C, the phrase can refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the terms "use", "using", and "used" may be considered to be synonymous with the terms "utilize", "utilizing", and "utilized", respectively. As used herein, the terms "substantially", "about", and similar terms are used as approximate terms rather than terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by a person of ordinary skill in the art.

[0043] It should be understood that although terms such as "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Thus, a first element, component, region, layer or part discussed below may be referred to as a second element, component, region, layer or part without departing from the teachings of the exemplary embodiments.

[0044] For ease of description, spatial relative terms such as "beneath", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or feature to another or other elements or features as shown in the figures. It should be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. For example, if the device in the figures is turned over, an element described as "beneath" or "below" other elements or features will be oriented "above" or "over" the other elements or features. Thus, the term "beneath" can encompass both an orientation of above and below. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and the spatial relative descriptors used herein should be interpreted accordingly.

[0045] The terms used herein are for the purpose of describing embodiments of the present disclosure and are not intended to limit the present disclosure. As used herein, the singular forms "a" and "an" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that when used in this specification, the terms "includes", "including", "comprises" and / or "comprising" specify the presence of the stated features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0046] In addition, any numerical range disclosed and / or described herein is intended to include all sub-ranges of the same numerical precision contained within that range. For example, the range "1.0 to 10.0" is intended to include all sub-ranges between the minimum value of 1.0 and the maximum value of 10.0 (and including the endpoints), that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit described herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit described in this specification is intended to include all higher numerical limits contained therein. Accordingly, the applicant reserves the right to modify this specification (including the claims) to expressly recite any sub-ranges contained within the ranges expressly recited herein.

[0047] Referring to two compared elements, features, etc. as "the same" may mean that they are "substantially the same". Thus, the phrase "substantially the same" may include cases having a deviation considered low in the art, such as a deviation of 5% or less. Additionally, when a certain parameter is said to be uniform in a given region, it may mean that it is uniform in terms of the average value.

[0048] Throughout the specification, unless otherwise stated, each element may be singular or plural.

[0049] Any element disposed "above (or below)" or "on (or under)" another element may mean that the any element may be placed in contact with the upper (or lower) surface of the element, and another element may also be interposed between the element and the any element disposed on (or under) the element.

[0050] In addition, it should be understood that when a component is referred to as being "linked", "coupled" or "connected" to another component, these components may be "coupled", "linked" or "connected" directly to each other, or another component may be "interposed" between these components.

[0051] Throughout the specification, unless otherwise stated, when stating "A and / or B", it means A, B, or A and B. That is, "and / or" includes any or all combinations of the recited items. When stating "C to D", unless otherwise stated, it means C or greater and D or less.

[0052] Figure 1 An example of a secondary battery 100 according to some embodiments of the present disclosure is shown. In an embodiment, the secondary battery 100 may include an electrode assembly, a case 140 provided to accommodate the electrode assembly and an electrolyte therein, and a cap assembly 150 coupled to an opening of the case 140 to seal the opening of the case 140.

[0053] The electrode assembly may include a first electrode 120, a second electrode 110, and a separator 130 disposed between the first electrode 120 and the second electrode 110. The electrode assembly may be wound, folded, or stacked to be received in a housing 140. Figure 1 The structure of the housing 140 having a cylindrical shape is shown, but the scope of the present disclosure is not limited thereto. For example, the housing 140 of the secondary battery 100 of the present disclosure may have any shape, such as cylindrical, rectangular, pouch-shaped, or circular.

[0054] The first electrode 120 may include a first current collector and a first active material layer formed on the first current collector. The first tab may be formed to extend outward from a first uncoated region of the first current collector where the first active material layer is not formed, and the first tab may be electrically coupled to the cap assembly 150 or the housing 140.

[0055] The second electrode 110 may include a second current collector and a second active material layer formed on the second current collector. The second tab may be formed to extend outward from a second uncoated region of the second current collector where the second active material layer is not formed, and the second tab may be electrically coupled to the housing 140 or the cap assembly 150. In an embodiment, the first tab and the second tab may be formed to extend in opposite directions.

[0056] The first electrode 120 may serve as a positive electrode. In this case, the first current collector may be formed of, for example, aluminum foil, and the first active material layer may include, for example, a transition metal oxide. The second electrode 110 may serve as a negative electrode. In this case, the second current collector may be formed of, for example, copper foil or nickel foil, and the second active material layer may include, for example, graphite.

[0057] In an embodiment, a plurality of secondary batteries 100 may be stacked to form a battery pack. The battery pack may be used in any device that requires high capacity and high output, such as a laptop computer, a smart phone, an electric vehicle, etc.

[0058] The secondary battery 100 may be a lithium secondary battery, a sodium secondary battery, etc. However, the scope of the present disclosure is not limited thereto, and the secondary battery 100 may include any battery capable of repeatedly providing power through charge and discharge operations. In an embodiment, in the case where the secondary battery 100 is a lithium secondary battery, the secondary battery 100 may be used in an electric vehicle (EV) due to its excellent cycle life and high rate performance. For example, the lithium secondary battery may be used in a hybrid vehicle such as a plug-in hybrid electric vehicle (PHEV). The lithium secondary battery may also be used in applications that require a large amount of power storage. For example, the lithium secondary battery may be used in electric bicycles, power tools, and similar applications.

[0059] Figures 2 to 5Shows a comparative example of an electrode plate according to some embodiments of the present disclosure. According to some embodiments, a negative electrode plate for a secondary battery includes a substrate 202 and a negative electrode active material layer provided on or on top of the substrate. The negative electrode active material layer may contain a negative electrode active material and may further contain a binder and / or a conductive material.

[0060] Figure 2 Shows an example of an electrode plate 200 according to the first comparative example. According to the first comparative example, a single active material layer 204 may be formed on top of the substrate 202. Here, the active material layer 204 may also contain a negative electrode active material and a binder. In addition, the negative electrode active material may include a carbon-based negative electrode active material, a silicon-based negative electrode active material, or a combination thereof.

[0061] In an example where a single active material layer 204 is formed using a carbon-based negative electrode active material, compared with an example using a silicon-based negative electrode active material, there may be a problem of lower energy density. By using a silicon-based negative electrode active material instead of a carbon-based negative electrode active material, this problem can be solved or substantially alleviated. However, in this example, due to the volume expansion of the silicon-based negative electrode active material, there may be a problem of shortened battery life.

[0062] Therefore, in a plate including a single active material layer 204, from the perspective of increasing battery capacity, it is desirable to increase the content of the silicon-based negative electrode active material, but from the perspective of extending battery life, it is also desirable to increase the content of the carbon-based negative electrode active material, such that there is a problem that capacity cannot be increased and battery life cannot be extended. In addition, in order to manufacture a plate with sufficient energy density, an active material layer having a set or predetermined thickness or a greater thickness needs to be formed, but in an example where the plate includes a single active material layer 204, it is difficult to uniformly apply an active material layer having a set or predetermined thickness or a greater thickness.

[0063] Figure 3 and Figure 4 Shows an example of cross-sections of plates 210 and 220 according to the second comparative example. According to the second comparative example, a plurality of active material layers may be formed on top of the substrate 202. For example, as Figure 3 shown, a first active material layer 212 may be formed on top of the substrate 202, and a second active material layer 214 may be formed on top of the first active material layer 212. Additionally, as Figure 4 shown, a first active material layer 222 may be formed on top of the substrate 202, a second active material layer 224 may be formed on the first active material layer 222, and a third active material layer 226 may be formed on top of the second active material layer 224.

[0064] In this example, the problem of applying an active material layer having a set or predetermined thickness or greater thickness all at once can be overcome by sequentially applying the active material layer. Additionally, by alternately applying a carbon-based negative electrode active material and a silicon-based negative electrode active material, the problem of shortened lifespan of the silicon-based negative electrode active material due to volume expansion can be partially solved.

[0065] However, in the example of sequentially applying the active material layer, there is a problem that the process takes a long time. For example, in an example where the active material is applied multiple times by, for example, applying a first active material on top of a substrate, drying the first active material, and then applying a second active material, the manufacturing time of the electrode plate may be extended, thereby disadvantageously reducing productivity.

[0066] Figure 5 An example of a cross-section of an electrode plate 230 produced by a continuous process using a slot die coater 300 according to some embodiments of the present disclosure is shown. As Figure 5 shown, a first active material layer 232 including a first active material 242 can be formed on top of a substrate 202 of the electrode plate 230, and a second active material layer 234 including a second active material 244 can be formed on the first active material layer 232. In this example, the second active material 244 can be applied in a strip pattern. Thereafter, a third active material 246 can be applied to the second active material layer 234 and a third active material layer 236. That is, the second active material 244 and the third active material 246 can be alternately arranged on the second active material layer 234. Additionally, each of the first active material 242 and the third active material 246 can include a carbon-based negative electrode active material, and the second active material 244 can include a silicon-based negative electrode active material. Thus, an electrode plate having a structure in which a silicon-based negative electrode active material (e.g., the second active material) is wrapped in a carbon-based negative electrode active material (e.g., the first active material or the third active material) can be manufactured.

[0067] In this embodiment, the effect of physically suppressing the expansion of the silicon-based negative electrode active material by the carbon-based negative electrode active material can be achieved. As a result, the stability of the electrode plate can be improved (e.g., increased) and the lifespan of the battery can be extended. Furthermore, by manufacturing the electrode plate 230 using a single slot die coater 300 in a continuous process, the problem of reduced productivity due to extended manufacturing time can be solved or substantially alleviated.

[0068] Figure 6Illustrates the configuration of a slot die coater 300 according to some embodiments of the present disclosure. The slot die coater 300 according to some embodiments of the present disclosure may include four die blocks 340 to 370 and three slots 310 and 330 respectively formed between corresponding die blocks among the die blocks 340 to 370. In addition, the slot die coater 300 may include spacers 410 to 440 provided between the die blocks 340 to 370 and inserted into the slots 310 and 330. Accordingly, a path may be formed to allow the active material to flow through the slots 310 and 330, and the flowing active material may be dispensed, the flow rate and position of which are controlled by the spacers 410 and 440.

[0069] The die blocks 340 to 370 included in the slot die coater 300 may be stacked and sequentially aligned in the traveling direction of the electrode plate. Accordingly, the slots 310 and 330 formed between the die blocks 340 to 370 may also be aligned in the traveling direction of the electrode plate.

[0070] According to some embodiments, the first spacer 410 may be inserted into the first slot 310. Accordingly, the first active material that has flowed through the first slot 310 may be dispensed through the first spacer 410. In addition, an opening cut in the direction of dispensing the active material may be formed in the first spacer 410. The flow rate and position of the first active material dispensed through the first spacer 410 may be controlled through the opening. Accordingly, the width of the first active material dispensed through the first spacer 410 may be determined to be equal to the width of the opening formed in the first spacer 410.

[0071] According to some embodiments, the second spacer 420 may be inserted into the second slot 320 in the direction of dispensing the active material. The slit portion formed in the second spacer 420 may be configured such that a plurality of slits and a plurality of teeth are alternately repeated, and the second active material dispensed through the second spacer 420 may be dispensed through the slits. The flow rate and position of the second active material dispensed through the second spacer 420 may be controlled through the slit portion.

[0072] According to some embodiments, the 3_1 spacer 430 (also referred to as the first third spacer) and the 3_2 spacer 440 (also referred to as the second third spacer) may be inserted into the third slot 330 in an overlapping state. Accordingly, the third active material that has flowed through the third slot 330 may be dispensed through the 3_1 spacer 430 and the 3_2 spacer 440.

[0073] The 3_1 separator 430 may have a slit portion having a plurality of slits formed in the direction of dispensing the active material (e.g., in the overall flow direction of the active material). The slit portion formed in the 3_1 separator 430 may be configured such that the slits and teeth are alternately repeated, so that the third active material dispensed through the 3_1 separator 430 can be dispensed through the slits. The flow rate and position of the third active material dispensed through the 3_1 separator 430 can be controlled by the slit portion.

[0074] In addition, the 3_1 separator 430 may have an opening cut in the direction of dispensing the active material, so that the third active material can be dispensed over a width equal to the width of the opening formed in the 3_1 separator 430. The thickness of the 3_1 separator 430 and the thickness of the 3_2 separator 440 may be the same. The flow rate and position of the third active material dispensed through the 3_1 separator 430 can be controlled by the opening.

[0075] will be referred to later Figures 7 to 9 to describe the specific shape of the separator in more detail.

[0076] According to some embodiments, the slot die coater 300 may dispense the active material at an angle perpendicular to or inclined to the traveling direction of the electrode plate. The first active material dispensed from the first slot 310 may first contact the surface of the substrate and form a first active material layer. Thereafter, the second active material dispensed from the second slot 320 may form a second active material layer on top of the first active material layer. Thereafter, the third active material dispensed from the third slot 330 may form a third active material layer on top of the second active material layer. will be referred to later Figure 9 and Figure 10 to describe in further detail the specific shape of the active material layer formed by the slot die coater 300.

[0077] The above configuration may allow the slot die coater 300 to continuously apply the first active material, the second active material, and the third active material to the surface of the substrate as the electrode plate moves. Accordingly, the electrode plate coated by the slot die coater 300 may form an active material layer in the form of a multi-layer structure in which the first active material, the second active material, and the third active material are continuously stacked.

[0078] Figure 7 Examples of the first separator 410 and the 3_2 separator 440 according to some embodiments of the present disclosure are shown; Figure 8 Examples of the second separator 420 according to some embodiments of the present disclosure are shown; ​ Examples of the 3_1 separator 430 according to some embodiments of the present disclosure are shown.

[0079] Referring to ​, the first spacer 410 may include an opening 412 cut in the direction of dispensing the active material, wings 414 provided on opposite sides of the opening 412, and a flow portion 416 to which the active material is supplied.

[0080] According to some embodiments, the first active material received in the cavity associated with the first slit may be supplied through the flow portion 416 formed in the first spacer 410. The first active material supplied to the flow portion 416 may be dispensed through the opening 412 formed in the first spacer 410 to form an active material layer. The width of the active material layer applied through the first spacer 410 may be determined by the width A of the opening 412 formed in the first spacer 410.

[0081] The shape of the 3_2nd spacer 440 may be the same as the shape of the first spacer 410. Accordingly, the width A of the opening formed in the 3_2nd spacer 440 may be the same as the width A of the opening formed in the first spacer 410. Similarly, the width A of the active material layer applied through the 3_2nd spacer 440 may be the same as the width A of the active material layer applied through the first spacer 410.

[0082] Referring to ​ , the second spacer 420 may have a slit portion 422 formed in the direction of dispensing the active material, wings 424 formed on opposite sides of the slit portion 422, and a flow portion 426 through which the active material is supplied. Additionally, the slit portion 422 may be configured such that a plurality of slits 422_1 and a plurality of teeth 422_2 are alternately repeated.

[0083] According to some embodiments, the second active material flowing through the cavity associated with the second slit may be supplied through the flow portion 426 formed in the second spacer 420. The flow portion 426 refers to the upper region of the slit 422_1, and in ​ , its top and bottom are indicated by dashed lines. The second active material supplied to the flow portion 426 may be dispensed through the slit portion 422 corresponding to the lower region of the slit 422_1 formed in the second spacer 420 to form a stripe pattern of the active material layer. The slit portion 422 is shown in ​ such that its top and bottom are indicated by dashed lines. The total width of the application region of the active material layer formed through the second spacer 420 may be determined by the width B of the slit portion 422 formed between the wings 424 of the second spacer 420.

[0084] According to some embodiments, the widths W1 of the teeth 422_2 included in the slit portion 422 may be constant relative to each other. In addition, the widths W2 of the slits 422_1 included in the slit portion 422 may be constant relative to each other. For example, the slit portion 422 may be configured such that the teeth 422_2 having a first width W1 and the slits 422_1 having a second width W2 are alternately repeated. Accordingly, the active material layer formed through the second separator 420 may form a strip pattern of the active material layer, where the active material layer is applied at intervals corresponding to (e.g., substantially equal to) the first width W1 in the width direction and has a width corresponding to (e.g., substantially equal to) the second width W2.

[0085] Referring ​ , the 3_1 separator 430 may have a slit portion 432 formed in the direction of distributing the active material, wings 434 formed on opposite sides of the slit portion 432, and a flow portion 436 through which the active material is supplied. The slit portion 432 may be configured such that a plurality of slits 432_1 and a plurality of teeth 432_2 are alternately repeated.

[0086] According to some embodiments, the third active material flowing through the cavity connected to the third slit may be supplied through the flow portion 436 formed in the 3_1 separator 430. The flow portion 426 refers to the upper region of the slit 432_1, and in ​ , its top and bottom are represented by dashed lines.

[0087] The third active material supplied to the flow portion 436 may be distributed through the slit portion 432 formed in the 3_1 separator (first third separator) 430 to form a strip-patterned active material layer. The slit portion 432 refers to the lower region of the slit 432_1, and in ​ , its top and bottom are represented by dashed lines. The total width of the application region of the active material layer formed through the 3_1 separator 430 may be determined by the width A of the slit portion 432 formed between the wings 434 of the 3_1 separator 430.

[0088] According to some embodiments, the widths of the teeth included in the slit portion 432 may be constant relative to each other. In addition, the width W3 of the slits 432_3 formed at both the left end and the right end in the slits included in the slit portion 432 may be constant. Among the slits included in the slit portion 432, the widths of all the slits 432_1 except for the two slits 432_3 formed at both the left end and the right end may be constant. For example, the slit portion 432 may be configured such that the slits 432_3 having a third width W3 are formed at both the left end and the right end, and at the center, the teeth 432_2 having a second width W2 and the slits 432_1 having a first width W1 are alternately repeated.

[0089] According to some embodiments, the first width W1 and the third width W3 may be different from each other. According to some embodiments, the length ratio of the first width W1 and the third width W3 may be 5:6.5; however, this is merely an example, and the length ratio is not limited thereto.

[0090] According to some embodiments, the width W1 of the teeth 422_2 formed in the second spacer 420 and the width W1 of the slots 432_1 formed in the 3_1st spacer 430 may be the same. Additionally, the width W2 of the slots 422_1 formed in the second spacer 420 and the width W2 of the teeth 432_2 formed in the 3_1st spacer 430 may be the same. According to some embodiments, the ratio between the first width W1 and the second width W2 may be 5:3; however, this is merely an example, and the length ratio is not limited thereto.

[0091] Additionally, the width B of the slot portion 432 formed in the 3_1st spacer 430 may be smaller than the width A of the slot portion 422 formed in the second spacer 420. For example, the widths of the two wings 424 formed in the second spacer 420 may extend wider than the widths of the two wings 434 formed in the 3_1st spacer 430 by the third width W3. Accordingly, the slot 422_1 formed in the second spacer 420 and the slot 432_1 formed in the 3_1st spacer 430 may be aligned on the slot die coater 300 to be staggered with respect to each other. Due to this configuration, different active material layers of the strip pattern may be arranged to be staggered with respect to each other.

[0092] According to some embodiments, the distal end of the slot portion 432 of the 3_1st spacer 430 may be formed to retreat (e.g., formed inwardly) a set or predetermined length N from the end of the wing 434 of the 3_1st spacer 430. For example, the height of the slot portion 432 of the 3_1st spacer 430 may be shorter than the height of the wing 434 of the 3_1st spacer 430 by the set or predetermined length N. In response to providing the reverse length N (where the distal end of each tooth 432_2 formed in the slot portion 432 of the 3_1st spacer 430 retracts from the distal end of the wing 434 of the 3_1st spacer 430 by the reverse length N), the flow rate of the active material dispensed from the slot portion 432 may be adjusted. For example, the flow rate ratio between the active material flowing at the end of the slot 432_1 and the active material flowing at the end of the tooth 432_2 dispensed from the slot 432_1 formed in the slot portion 432 may be adjusted. An example of adjusting the flow rate ratio by the reverse length N will be described in further detail below with reference to ​ Examples of adjusting the flow rate ratio by the reverse length N are described in further detail below.

[0093] ​ An example of coating a substrate by using the spacers 410 to 440 according to some embodiments of the present disclosure is shown.

[0094] The first separator 410, the second separator 420, the 3_1 separator 430, and the 3_2 separator 440 can be inserted into the slot die coater 300 and can be sequentially aligned in the traveling direction of the electrode plate. Therefore, the slot die coater 300 can continuously apply the first active material 242, the second active material 244, and the third active material 246 to the surface of the substrate to form an active material layer in the form of a multilayer structure in which the first active material layer, the second active material layer, and the third active material layer are continuously stacked.

[0095] The first active material 242 dispensed through the first separator 410 can form the first active material layer. For example, the first active material 242 flowing into the first slot can be dispensed through the first separator 410 to form the first active material layer having the first thickness D1 on the substrate. The width of the first active material layer formed through the first separator 410 can be determined by the width A of the opening formed in the first separator 410. The width A of the opening can be defined as the internal distance between the opposing wings 434.

[0096] The second active material 244 dispensed through the second separator 420 can form the second active material layer. For example, the second active material 244 flowing into the second slot can be dispensed through the second separator 420 to form the second active material layer having the second thickness D2 on top of the first active material layer. The total width of the second active material layer formed through the second separator 420 can be determined by the width B of the opening formed in the second separator 420.

[0097] The second active material 244 dispensed through the second separator 420 can form an active material layer in a stripe pattern. For example, the coated portion having the second width W2 and the uncoated portion having the first width W1 can be alternately formed according to the width W2 of the slot and the width W1 of the teeth formed in the slot portion 422 of the second separator 420.

[0098] The third active material 246 dispensed through the 3_1 first separator 430 and the 3_2 second separator 440 can form the third active material layer. For example, the third active material 246 flowing into the third slot can be dispensed through the 3-1 separator 430 and the 3-2 separator 440 to form the third active material layer. The overall width of the third active material layer formed through the 3_1 separator 430 and the 3_2 separator 440 can be determined by the width A of the opening formed in the 3_1 separator 430 and the 3_2 separator 440.

[0099] The thickness of the third active material layer may vary according to the position of the electrode plate in the width direction. For example, an active material layer having a thickness d1 of 3_1 may be formed on top of the coated portion coated with the second active material layer, and an active material layer having a third thickness D3 may be formed on top of the uncoated portion not coated with the second active material layer. That is, a third active material layer in which the active material layer having a thickness d1 of 3_1 and the active material layer having a third thickness D3 are alternately repeated may be formed according to whether the second active material layer is coated or not.

[0100] The thickness ratio of the third active material layer according to the position in the width direction can be adjusted by the reverse length N applied to the slit portion of the 3_1 spacer 430. For example, by means of the reverse length N of the slit portion, a part of the active material distributed from the slit can flow to the end of the tooth. Therefore, the flow rate ratio of the active material flowing at the end of the slit to the active material flowing at the end of the tooth can be changed, so as to change the thickness of the third active material layer according to the position in the width direction.

[0101] For example, an active material layer having a third thickness D3 may be formed at a position corresponding to the slit, and an active material layer having a thickness d1 of 3_1 may be formed at a position corresponding to the tooth. That is, an active material layer having a first width W1 and a third thickness D3 may be formed on top of the uncoated portion not coated with the second active material layer, and an active material layer having a second width W2 and a thickness d1 of 3_1 may be formed on top of the coated portion coated with the second active material layer.

[0102] In some embodiments, the electrode plate 600 according to some embodiments of the present disclosure may be designed such that the ratio of the thickness D1 of the first active material layer, the thickness D2 of the second active material layer, and the thickness d1 of the third active material layer coated on top of the second active material layer is 1:1:1. In this example, the ratio between the thickness d1 of 3_1 in the third active material layer and the third thickness D3 may be designed to be 1:2.

[0103] In some embodiments, the flow rate ratio of the third active material 246 for manufacturing the electrode plate 600 having the above structure may be calculated based on the ratio of the thickness d1 of 3_1 and the third thickness D3. For example, since the ratio of the third thickness D3 to the thickness d1 of 3_1 is 2, the flow rate ratio of the third active material 246 flowing at each position can be calculated to be between 1 and 3. For example, the flow rate ratio of the third active material 246 flowing at each position can be calculated to be about 2.

[0104] The first active material layer, the second active material layer, and the third active material layer are in ​are shown as being spaced apart from each other, but this is for illustrative purposes only, and the first active material layer, the second active material layer, and the third active material layer may be sequentially stacked to have a stacked structure.

[0105] Table 1 below shows examples of the flow rate ratio calculated by differently changing the reverse length N of the slit portion applied to the 3_1 spacer 430 based on the thickness ratio of the third active material layer. Here, the flow rate ratio refers to the ratio of the flow rate of the active material flowing at the position corresponding to the slit in the 3_1 spacer 430 to the flow rate of the active material flowing at the position corresponding to the tooth.

[0106] Table 1

[0107] ​ ​ 5 1.80 4 1.92 3.8 1.96 3.6 2.01 3.4 2.06

[0108] According to Table 1, the reverse length N applied to the slit portion of the 3_1 spacer 430 is ideally designed to be between 3 mm and 4 mm. For example, the reverse length N applied to the slit portion of the 3_1 spacer 430 may correspond to approximately 3.6 mm. In this example, the ratio of the third thickness D3 to the 3_1 thickness d1 may correspond to 2. The third thickness D3 may correspond to the sum of the 3_1 thickness d1 and the 3_2 thickness d2, and in an example where the 3_1 thickness d1 and the 3_2 thickness d2 have the same or equal thickness, the ratio of the third thickness D3 to the 3_1 thickness d1 may correspond to 2.

[0109] In some other embodiments, the flow rate ratio of the third active material 246 for manufacturing the electrode plate 600 having the above configuration may be calculated based on the cross-sectional area of the third active material layer. For example, the cross-sectional area of the active material layer coated with the third thickness D3 may be determined as W1×D3, and the cross-sectional area of the active material layer coated with the 3_1 thickness d1 may be determined as W2×d1. That is, assuming that the ratio of the first width W1 to the second width W2 is 5:�, and the ratio of the third thickness D3 to the 3_1 thickness d1 is 2:1, the ratio of the cross-sectional areas of the corresponding active material layers may be determined as 10:3. In addition, since the ratio of the cross-sectional area W1xD3 to the cross-sectional area W2xd1 is 3.3, the ratio of the flow rates of the third active material 246 flowing at the corresponding positions may be calculated to be between 3 and 4. For example, the ratio of the flow rates of the third active material 246 flowing at the corresponding positions may be calculated to be approximately 3.33.

[0110] Table 2 below shows an example of the flow rate ratio calculated by varying the reverse length N applied to the slit portion of the 3_1 separator 430 differently based on the cross-sectional area ratio of the third active material layer. Here, the flow rate ratio refers to the ratio of the flow rate of the active material flowing at the position corresponding to the slit in the 3_1 separator 430 to the flow rate of the active material flowing at the position corresponding to the tooth.

[0111] Table 2

[0112] ​ ​ 2 2.90 1.75 3.23 1 5.22

[0113] According to Table 2, the reverse length N applied to the slit portion of the 3_1 separator 430 can be between 1 mm and 2 mm. For example, the reverse length N applied to the slit portion of the 3_1 separator 430 can be designed to be approximately 1.75 mm.

[0114] ​ Fig. shows a cross-sectional view of a plate electrode 500 according to some embodiments of the present disclosure.

[0115] According to some embodiments, the plate electrode 500 manufactured using the slit die coater 300 according to the present disclosure can form an active material layer in a multi-layer structure form in which a first active material layer, a second active material layer, and a third active material layer are sequentially stacked.

[0116] According to some embodiments, a first active material layer to which a first active material is applied can be formed on top of a substrate (e.g., ​ the dark shaded bottom layer in ). Thereafter, a second active material layer can be formed on top of the first active material layer. In the second active material layer, a first coating portion 510 coated with the second active material with a second width W2 and an uncoated portion 520 not coated with the second active material can be alternately formed. Thereafter, a third active material layer can be formed on top of the second active material layer. In the third active material layer, a second coating portion 530 coated with the third active material with the second width W2 and a third coating portion 540 coated with the third active material with a first width W1 can be alternately formed on top of the first coating portion 510 and the uncoated portion 520, respectively.

[0117] According to some embodiments, the content of the carbon-based material contained in each of the first active material and the third active material can be greater than the content of the carbon-based material contained in the second active material. In addition, the content of the silicon-based material contained in each of the first active material and the third active material can be less than the content of the silicon-based material contained in the second active material.

[0118] In the above configuration, the electrode plate 500 can be arranged such that the active material having a larger content of carbon-based material (e.g., the first active material or the third active material) wraps around the active material having a larger content of silicon-based material (e.g., the second active material). As a result, a structure can be formed in which the expansion of the silicon-based material is physically restricted by the carbon-based material. Therefore, the stability of the structure of the electrode plate can be improved (e.g., increased), thereby extending the life of the battery.

[0119] As the positive electrode active material, a compound capable of reversibly intercalating / deintercalating lithium (e.g., a lithiated intercalation compound) can be used. For example, at least one of composite oxides of lithium and metals selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0120] The composite oxide can be a lithium transition metal composite oxide, and examples thereof can include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0121] As an example, a compound represented by any of the following formulas can be used: Li a A 1-b X b O 2-c D c (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05); Li a Mn 2-b X b O 4-c D c (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.5, 0 < α < 2); Li a Ni 1-b-c Mn b X c O 2-α D α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.5, 0 < α < 2); Li a Ni b Co c L 1 d G e O2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, 0 ≤ e ≤ 0.1); Li a NiGb O2 (0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a CoG b O2 (0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn 1-b G b O2 (0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn2G b O4 (0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn 1-g G g PO4 (0.90 ≤ a ≤ 1.8, 0 ≤ g ≤ 0.5); Li (3-f) Fe2(PO4)3 (0 ≤ f ≤ 2), Li a FePO4 (0.90 ≤ a ≤ 1.8).

[0122] In the above formula: A is Ni, Co, Mn or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or a combination thereof; D is O, F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; and L 1 is Mn, Al or a combination thereof.

[0123] The positive electrode of the lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may contain a positive electrode active material and may further contain a binder and / or a conductive material.

[0124] Based on 100 wt% of the positive electrode active material layer, the content of the positive electrode active material is in the range of about 90 wt% to about 99.5 wt%, and based on 100 wt% of the positive electrode active material layer, the contents of the binder and the conductive material are respectively in the range of about 0.5 wt% to about 5 wt%.

[0125] The current collector may be aluminum (Al), but is not limited thereto.

[0126] The negative electrode active material may include a material capable of reversibly inserting / extracting lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and undoping lithium, or a transition metal oxide.

[0127] Materials capable of reversibly inserting / extracting lithium ions can be carbon-based negative electrode active materials, which can include, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon can include graphite, such as natural graphite or artificial graphite, and examples of amorphous carbon can include soft carbon, hard carbon, pitch carbide, mesophase pitch carbide, sintered coke, etc.

[0128] Si-based negative electrode active materials or Sn-based negative electrode active materials can be used as materials capable of doping or not doping with lithium. Si-based negative electrode active materials can be silicon, silicon-carbon composites, SiOx (0 < x < 2), Si-based alloys, or a combination thereof.

[0129] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to an embodiment, the silicon-carbon composite can be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0130] The silicon-carbon composite can further include crystalline carbon. For example, the silicon-carbon composite can include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0131] The negative electrode for a lithium secondary battery can include a current collector and a negative electrode active material layer provided on the current collector. The negative electrode active material layer can contain a negative electrode active material and can further contain a binder and / or a conductive material.

[0132] For example, the negative electrode active material layer can contain about 90 wt% to about 99 wt% of the negative electrode active material, about 0.5 wt% to about 5 wt% of the binder, and about 0 wt% to about 5 wt% of the conductive material.

[0133] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used as the binder. When using an aqueous binder as the negative electrode binder, a cellulose-based compound capable of imparting viscosity can be further included.

[0134] As the negative electrode current collector, one selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a conductive metal-coated polymer substrate, and a combination thereof can be used.

[0135] The electrolyte for a lithium secondary battery can include a non-aqueous organic solvent and a lithium salt.

[0136] The non-aqueous organic solvent acts as a medium through which ions participating in the electrochemical reaction of the battery can move.

[0137] The non-aqueous organic solvent can be a carbonate-based, ester-based, ether-based, ketone-based, alcohol-based solvent, an aprotic solvent, and can be used alone or in combination of two or more.

[0138] In addition, when using a carbonate-based solvent, a mixture of a cyclic carbonate and a linear carbonate can be used.

[0139] Depending on the type of the lithium secondary battery, a separator may be present between the first electrode plate (e.g., the negative electrode) and the second electrode plate (e.g., the positive electrode). As the separator, polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof can be used.

[0140] The separator may include a porous substrate and a coating containing an organic material, an inorganic material, or a combination thereof on one or both surfaces of the porous substrate.

[0141] The organic material may include a polyvinylidene fluoride-based heavy antibody or a (meth)acrylic polymer.

[0142] The inorganic material may include inorganic particles selected from the following: Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but not limited thereto.

[0143] The organic material and the inorganic material can be mixed in one coating, or can be in the form of a coating containing an organic material and a coating containing an inorganic material laminated to each other.

[0144] Although the present disclosure has been described above with respect to embodiments of the present disclosure, the present disclosure is not limited thereto. Those skilled in the art can make various modifications and variations within the spirit of the present disclosure and the scope equivalent to the appended claims.

[0145] Reference Numerals

[0146] 100: Secondary Battery

[0147] 110: Second Electrode

[0148] 120: First Electrode

[0149] 130: Separator

[0150] 140: Case

[0151] 150: Cap Assembly

Claims

1. A slit die coater, comprising: A slit die configured to include a first slit, a second slit, and a third slit, through which a first active material, a second active material, and a third active material are respectively dispensed; And A first spacer, a second spacer, and a third spacer respectively inserted into the first slit, the second slit, and the third slit for dispensing the first active material, the second active material, and the third active material, Wherein the first slit, the second slit, and the third slit are sequentially aligned in the traveling direction of the substrate movement to form an active material coating layer having multiple layers, and the active materials dispensed through the first spacer, the second spacer, and the third spacer are stacked in the multiple layers.

2. The slit die coater according to claim 1, wherein the content of the carbon-based material in each of the first active material and the third active material is greater than the content of the carbon-based material in the second active material, and Wherein the content of the silicon-based material in each of the first active material and the third active material is less than the content of the silicon-based material in the second active material.

3. The slit die coater according to claim 1, wherein the third spacer includes a first third spacer and a second third spacer aligned to contact the first third spacer, and Wherein the first third spacer and the second third spacer have different shapes.

4. The slit die coater according to claim 3, wherein the thickness of the first third spacer is equal to the thickness of the second third spacer.

5. The slit die coater according to claim 3, wherein each of the first spacer and the second third spacer has an opening provided as a cutout in one of its regions to determine the width of the active material for coating the substrate.

6. The slit die coater according to claim 3, wherein each of the second spacer and the first third spacer includes a slit portion having a plurality of slits to determine the width of the active material for coating the substrate, and Among them, An active material coating layer having a stripe pattern is formed through the slit portion.

7. The slit die coater according to claim 6, wherein the slit portion of the first third spacer is configured such that the slits and a plurality of teeth are alternately repeated, wherein each slit has a first width and each tooth has a second width, and Among them, The slit portion of the second spacer is configured such that the slits and a plurality of teeth are alternately repeated, wherein each slit has the second width and each tooth has the first width.

8. The slit die coater according to claim 7, wherein the slits in the second spacer and the slits in the first third spacer are arranged to be staggered with respect to each other.

9. The slit die coater according to claim 7, wherein the first width is longer than the second width.

10. The slot die coater according to claim 7, wherein, The length of the teeth in the first and third spacers is shorter than the length of the teeth in the second spacer by a set length, such that the distal ends of the teeth provided in the first and third spacers are aligned to form the set length inward from the distal ends of the teeth in the second spacer.

11. The slot die coater according to claim 10, wherein a first coated portion coated with the second active material at the second width and an uncoated portion not coated with the second active material are alternately arranged using the second spacer, and Among them, a second coated portion coated with the third active material at the second width and a third coated portion coated with the third active material at the first width are alternately arranged on top of the first coated portion and the uncoated portion using the first and third spacers and the second and third spacers.

12. The slot die coater according to claim 11, wherein, The thickness of the first coated portion corresponds to the thickness of the second coated portion, and the thickness of the third coated portion is different from the thicknesses of the first coated portion and the second coated portion.

13. The slot die coater according to claim 11, wherein the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 1 and 3.

14. The slot die coater according to claim 13, wherein the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 1.9 and 2.

1.

15. The slot die coater according to claim 11, wherein the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 3 and 4.

16. The slot die coater according to claim 15, wherein the flow rate ratio of the third active material coated on the third coated portion to the third active material coated on the second coated portion is between 3.2 and 3.

4.

17. The slot die coater according to claim 13, wherein the set length is 4 mm or less.

18. The slot die coater according to claim 15, wherein the set length is 2 mm or less.

19. A plate electrode, comprising: a substrate; and a first active material layer, a second active material layer, and a third active material layer, configured to coat a surface of the substrate, wherein the first active material layer is coated with a first active material, wherein the third active material layer is coated with a third active material, and wherein the second active material layer is coated with the third active material and a second active material alternately arranged in the width direction of the substrate.

20. The electrode plate according to claim 19, wherein, The content of the carbon-based material in each of the first active material and the third active material is greater than the content of the carbon-based material in the second active material, and wherein the content of the silicon-based material in each of the first active material and the third active material is less than the content of the silicon-based material in the second active material.

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