Apparatus for manufacturing electrode plate and method for manufacturing electrode plate

Abstract

The present invention provides an apparatus for manufacturing an electrode plate and a method for manufacturing an electrode plate. The apparatus (1) for manufacturing an electrode plate (100) includes: a conveyor line (2) for the electrode plate (100), the electrode plate (100) having a coating portion on the surface of a substrate coated with an electrode active material and an uncoated portion on the surface of the substrate not coated with an electrode active material; a compression roller (4) disposed on the conveyor line (2) for compressing the coating portion; and a tension reduction mechanism (6) disposed on at least one of an upstream section of the conveyor line (2) with the compression roller (4) as the terminal and a downstream section with the compression roller (4) as the starting point, for reducing the tension applied to the electrode plate (100).

Description

Technical Field

[0001] This invention relates to an apparatus for manufacturing electrode plates and a method for manufacturing electrode plates. Background Technology

[0002] Generally, electrode plates used in lithium-ion secondary batteries have a structure in which an electrode active material is coated on the surface of a substrate (current collector) made of aluminum foil, copper foil, etc. Additionally, the electrode plate has an uncoated portion on the surface of the substrate where no electrode active material is coated. This uncoated portion functions, for example, as a current collector. In other words, the electrode plate has a coated portion consisting of layers of substrate and electrode active material, and an uncoated portion consisting only of the substrate.

[0003] As a method for manufacturing such an electrode plate, the following method is known: while conveying a strip of substrate, an electrode active material is continuously coated onto the central portion of the substrate in the width direction to form a strip of electrode plate. The strip of electrode plate has a coated portion extending along the conveying direction in the central portion of the substrate and an uncoated portion extending along the conveying direction at the ends of the substrate. Furthermore, for the purpose of increasing the density of the electrode active material and achieving uniform thickness, a method for compressing the coated portion of the electrode plate using a roller press is known. Typically, the electrode plate after the coated portion is compressed is wound into a roll and transferred to the next process. In the downstream process, the electrode plate is individually split into multiple sheets, stacked with partitions, and sealed into an outer packaging can.

[0004] Ideally, when the coating section is compressed, only the electrode active material is compressed, and the substrate constituting the coating section is not rolled. However, in reality, if the coating section is compressed, the substrate is also rolled. On the other hand, since the thickness of the uncoated section is thinner than that of the coating section, the substrate constituting the uncoated section is not rolled during the compression of the coating section. As a result, a difference arises between the length of the coating section and the length of the uncoated section. If such a length deviation occurs, wrinkles will form on the electrode plate, and the transport and winding of the electrode plate may be hindered.

[0005] In response to this, for example, Patent Document 1 discloses the following method: an active material coated sheet having a strip-shaped coated portion in the center of a metal foil and a strip-shaped uncoated portion at the edge of the metal foil is passed between pressure rollers to form a strip electrode; the deformation between the coated portion and the uncoated portion is eased by applying tension to the strip electrode while heating the uncoated portion; and the strip electrode is cut after the deformation is eased to make the sheet electrode a single piece.

[0006] [Prior Technology Documents]

[0007] [Patent Literature]

[0008] Patent Document 1: Japanese Patent Application Publication No. 2005-93236 Summary of the Invention

[0009] [The problem the invention aims to solve]

[0010] The inventors conducted in-depth research on the aforementioned conventional methods and discovered that if a process for eliminating the length deviation between the coated and uncoated sections is provided in the conveyor line, the possibility of electrode plate breakage during compression of the coated section is increased.

[0011] This disclosure was made in view of the above circumstances, and one of its objectives is to provide a more stable technique for manufacturing electrode plates.

[0012] [Technical solutions used to address technical problems]

[0013] One aspect of this disclosure is an apparatus for manufacturing an electrode plate. The apparatus includes: a conveyor line for the electrode plate, the electrode plate having a coating portion on the surface of a substrate coated with an electrode active material and an uncoated portion on the surface of the substrate without the electrode active material coated; a compression roller disposed on the conveyor line for compressing the coating portion; and a tension reduction mechanism disposed on at least one of an upstream section terminating at the compression roller and a downstream section originating from the compression roller in the conveyor line, for reducing the tension applied to the electrode plate.

[0014] Another aspect of this disclosure is a method for manufacturing an electrode plate. The method includes the following steps: conveying an electrode plate having a coated portion on the surface of a substrate coated with an electrode active material and an uncoated portion on the surface of the substrate where no electrode active material is coated; compressing the coated portion of the conveyed electrode plate; and reducing the tension applied to the electrode plate in at least one of an upstream section ending at the compression position and a downstream section beginning at the compression position.

[0015] Any combination of the above-mentioned constituent elements, as well as schemes that convert the manifestation of this disclosure into methods, apparatus, systems, etc., are also valid as solutions to this disclosure.

[0016] [Invention Effects]

[0017] According to this disclosure, electrode plates can be manufactured more stably. Attached Figure Description

[0018] Figure 1 This is a side view schematically illustrating the manufacturing apparatus for an electrode plate according to an embodiment.

[0019] Figure 2 (A) is a top view schematically showing the conveying mechanism conveying the electrode plate. Figure 2 (B) is a schematic cross-sectional view showing the conveying mechanism conveying the electrode plate.

[0020] Figure 3 This is a graph showing the relationship between the size ratio a / b and the tension applied to the electrode plate.

[0021] Figure 4 This is a schematic diagram of the uncoated stretching roller of the stretching mechanism.

[0022] Figure 5 This is a graph showing the relationship between the presence or absence of the first and second tension reduction mechanisms and the elongation of the coated portion. Detailed Implementation

[0023] The present disclosure will now be described based on preferred embodiments and with reference to the accompanying drawings. These embodiments are illustrative rather than limiting, and not all features and combinations thereof described in the embodiments constitute the essential content of the present disclosure. Identical or equivalent constituent elements, components, and processes shown in the various drawings are labeled with the same reference numerals, and repetitive descriptions are omitted where appropriate. Furthermore, the scales and shapes of the parts shown in the figures are conveniently set for ease of explanation and are not interpreted as limiting unless specifically mentioned. Additionally, the use of terms such as "first," "second," etc., in this specification or claims does not indicate any order or importance unless specifically mentioned, but is used to distinguish one component from others. Furthermore, in the accompanying drawings, some less important components are omitted from the description of the embodiments.

[0024] Figure 1 This is a side view schematically illustrating the manufacturing apparatus for an electrode plate according to an embodiment. Figure 2 (A) is a top view schematically showing the conveying mechanism conveying the electrode plate. Figure 2 (B) is a schematic cross-sectional view showing the conveying mechanism conveying the electrode plate.

[0025] The electrode plate manufacturing apparatus 1 includes a conveyor line 2, a compression roller 4, a tension reduction mechanism 6, and a stretching mechanism 8. In this embodiment of the manufacturing apparatus 1, a tension reduction mechanism 6 and a stretching mechanism 8 are provided on both the upstream and downstream sides of the compression roller 4 in the conveyor line 2. Hereinafter, the tension reduction mechanism 6 on the upstream side will be referred to as the first tension reduction mechanism 6a, and the tension reduction mechanism 6 on the downstream side will be referred to as the second tension reduction mechanism 6b. In addition, when it is not necessary to distinguish between the first tension reduction mechanism 6a and the second tension reduction mechanism 6b, they will be collectively referred to as tension reduction mechanism 6. Similarly, the stretching mechanism 8 on the upstream side will be referred to as the first stretching mechanism 8a, and the stretching mechanism on the downstream side will be referred to as the second stretching mechanism 8b, and when it is not necessary to distinguish between the two, they will be collectively referred to as stretching mechanism 8.

[0026] The conveyor line 2 is a mechanism for conveying the electrode plate 100. The electrode plate 100 has a coated portion 104 on the surface of a long strip substrate 102 where an electrode active material is coated, and an uncoated portion 106 on the surface of the substrate 102 where no electrode active material is coated. The substrate 102 functions as a current collector. When the electrode plate 100 is the negative electrode plate of a lithium-ion secondary electrode, the substrate 102 is, for example, made of a foil or porous body made of copper or aluminum. When the electrode plate 100 is the positive electrode plate of a lithium-ion secondary electrode, the substrate 102 is, for example, made of a foil or porous body made of stainless steel or aluminum.

[0027] When the electrode plate 100 is the negative electrode plate of a lithium-ion secondary electrode, the electrode active material is graphite or the like. When the electrode plate 100 is the positive electrode plate of a lithium-ion secondary electrode, the electrode active material is lithium cobalt oxide, lithium iron phosphate, or the like. The electrode active material is coated onto the substrate 102, for example, in the form of an electrode paste containing conductive additives, binders, dispersants, etc. After coating the electrode paste, the coating film is dried and rolled to form an electrode active material layer 108. In this embodiment, the electrode active material layer 108 is provided on both sides of the substrate 102. The coated portion 104 has a structure in which the substrate 102 and the electrode active material layer 108 are stacked. On the other hand, the uncoated portion 106 is composed only of the substrate 102.

[0028] The conveyor line 2 includes an unwinding device 10, a winding device 12, and a conveying mechanism 14. The unwinding device 10 is located at the beginning of the conveyor line 2. The unwinding device 10 holds the electrode 100, which has not undergone the compression treatment of the coating portion 104, in a wound state, and conveys it downstream of the conveyor line 2. The winding device 12 is located at the end of the conveyor line 2. The winding device 12, for example, retracts the electrode plate 100, which has undergone the compression treatment of the coating portion 104, in a wound state.

[0029] The conveying mechanism 14 is disposed between the unwinding device 10 and the winding device 12 on the conveyor line 2, and conveys the electrode plate 100 from the unwinding device 10 to the winding device 12. In this embodiment, the conveying mechanism 14 includes a first conveying mechanism 14a, a second conveying mechanism 14b, a third conveying mechanism 14c, and a fourth conveying mechanism 14d. The first conveying mechanism 14a to the fourth conveying mechanism 14d are arranged sequentially at predetermined intervals from the upstream side of the conveying direction A of the electrode plate 100. Hereinafter, unless it is necessary to distinguish between the first conveying mechanism 14a to the fourth conveying mechanism 14d, they will be collectively referred to as the conveying mechanism 14. Furthermore, the number of conveying mechanisms 14 is not limited to four.

[0030] In this embodiment, the conveying mechanism 14 is composed of clamping rollers that hold and convey the electrode plate 100. The conveying mechanism 14 holds the coating portion 104 and conveys the electrode plate 100. Therefore, the conveying mechanism 14 does not come into contact with the uncoated portion 106. As a result, when conveying the electrode plate 100 in a state where the uncoated portion 106 is stretched more than the coating portion 104 by the stretching mechanism 8 described later, wrinkles in the uncoated portion 106 can be suppressed. Therefore, the configuration of the conveying mechanism 14 holding only the coating portion 104 is particularly preferred when applied to the second conveying mechanism 14a, which determines the downstream end of the first stretching mechanism 8a.

[0031] In addition, such as Figure 2 As shown in (B), the conveying mechanism 14 is designed such that when the dimension of the width direction B of the portion of the coating section 104 held by the conveying mechanism 14 is set to a, and the dimension of the width direction B of the coating section 104 is set to b, a / b ≥ 0.4. The width direction B is a direction orthogonal to the conveying direction A of the electrode plate 100.

[0032] Figure 3 This is a graph showing the relationship between the size ratio a / b and the tension applied to the electrode plate 100. The "tension" on the vertical axis is the ratio of the tension obtained for each a / b ratio to the tension obtained when the conveying mechanism 14 holds the entire width of the coating section 104 (i.e., a / b is 1). Figure 3 As shown, when a / b = 0.4, 90% of the tension obtained when a / b = 1 can be achieved. Therefore, by designing the conveying mechanism 14 with a / b of 0.4 or higher, wrinkling of the uncoated portion 106 can be suppressed, and the decrease in the conveying speed of the electrode plate 100 can be suppressed more reliably. Furthermore, a / b of 0.53 or higher is preferred.

[0033] Furthermore, the conveying mechanism 14 may also be configured to adsorb and transport the electrode plate 100. For example, the conveying mechanism 14 may be composed of suction rollers or the like. In this case, dimension a is the dimension in the width direction B of the portion of the coating section 104 that is adsorbed by the conveying mechanism 14. Alternatively, the conveying mechanism 14 may have multiple clamping rollers or suction rollers arranged in the width direction B. In this case, the total dimension of the portion held or adsorbed by each roller is dimension a.

[0034] A compression roller 4 is provided between the second conveying mechanism 14b and the third conveying mechanism 14c in the conveyor line 2. The compression roller 4 is a pair of rollers arranged at a predetermined interval. By passing the electrode plate 100 between the pair of rollers, pressure can be applied to the coating section 104 in the thickness direction of the electrode plate 100. As a result, the coating section 104 is compressed.

[0035] The electrode plate 100 is also conveyed by the rotation of the compression roller 4. Therefore, the compression roller 4 also functions as a clamping roller. A tension adjustment section is provided in the interval between each clamping roller (i.e., each conveying mechanism 14 and the compression roller 4), and the tension applied to the electrode plate 100 conveyed on the conveyor line 2 is adjusted independently in each interval. In this embodiment, the tension adjustment section is composed of a tension adjustment roller.

[0036] Specifically, a first tension adjustment unit 16a is provided in the first interval R1 between the first conveying mechanism 14a and the second conveying mechanism 14b. A second tension adjustment unit 16b is provided in the second interval R2 between the second conveying mechanism 14b and the compression roller 4. A third tension adjustment unit 16c is provided in the third interval R3 between the compression roller 4 and the third conveying mechanism 14c. A fourth tension adjustment unit 16d is provided in the fourth interval R4 between the third conveying mechanism 14c and the fourth conveying mechanism 14d.

[0037] A first tension measuring device 18a is provided in the first section R1 to measure the tension applied to the electrode plate 100 by the first tension adjustment unit 16a. A second tension measuring device 18b is provided in the second section R2 to measure the tension applied to the electrode plate 100 by the second tension adjustment unit 16b. A third tension measuring device 18c is provided in the third section R3 to measure the tension applied to the electrode plate 100 by the third tension adjustment unit 16c. A fourth tension measuring device 18d is provided in the fourth section R4 to measure the tension applied to the electrode plate 100 by the fourth tension adjustment unit 16d. Examples of the first tension measuring device 18a to the fourth tension measuring device 18d include known contact tension gauges, tension rollers, etc.

[0038] The operation of the compression roller 4, the conveying mechanism 14, and the first tension adjustment units 16a to the fourth tension adjustment units 16d is controlled by the control device 20. The control device 20, as hardware, is implemented by components and circuits, such as a computer's CPU and memory; as software, it is implemented through computer programs, etc. Figure 1 The diagram depicts functional blocks implemented through their collaboration. Those skilled in the art will naturally understand that these functional blocks can be implemented in various forms through a combination of hardware and software.

[0039] The control device 20 receives tension data from the first tension measuring device 18a to the fourth tension measuring device 18d, and controls the driving of the first tension adjustment unit 16a to the fourth tension adjustment unit 16d based on the received tension data. Thus, the tension applied to the electrode plate 100 can be adjusted to the desired value within the first interval R1 to the fourth interval R4. Furthermore, the control device 20 can also perform control based on a pre-set fixed operating procedure, rather than feedback control based on the measurement results of the first tension measuring device 18a to the fourth tension measuring device 18d.

[0040] A first tension reduction mechanism 6a is provided upstream of the compression roller 4 in the conveyor line 2. The first tension reduction mechanism 6a is located in the second section R2 and reduces the tension applied to the electrode plate 100 in the second section R2. That is, the first tension reduction mechanism 6a is located in the upstream section of the conveyor line 2, with the compression roller 4 as its terminal. The first tension reduction mechanism 6a consists of a second tension adjustment unit 16b, a second tension measuring device 18b, a guide roller 21, and a control device 20. Based on the measurement results of the second tension measuring device 18b, the control device 20 drives the second tension adjustment unit 16b, reducing the tension applied to the electrode plate 100 in the second section R2 compared to the tension applied to the electrode plate 100 in the first section R1. For example, the tension applied to the electrode plate 100 in the second section R2 is adjusted to 0.

[0041] Furthermore, a second tension reduction mechanism 6b is provided downstream of the compression roller 4. The second tension reduction mechanism 6b is located in the third interval R3 and reduces the tension applied to the electrode plate 100 in the third interval R3. That is, the second tension reduction mechanism 6b is located in the downstream interval starting from the compression roller 4. The second tension reduction mechanism 6b is composed of a third tension adjustment unit 16c, a third tension measuring device 18c, a guide roller 21, and a control device 20. Based on the measurement results of the third tension measuring device 18c, the control device 20 drives the third tension adjustment unit 16c, reducing the tension applied to the electrode plate 100 in the third interval R3 compared to the tension applied to the electrode plate 100 in the fourth interval R4. For example, the tension applied to the electrode plate 100 in the third interval R3 is adjusted to 0.

[0042] The stretching mechanism 8 is located in the conveyor line 2 at a position away from the tension reduction mechanism 6 and the compression roller 4, and stretches the uncoated portion 106. In this embodiment, the first stretching mechanism 8a is provided in the first interval R1 upstream of the first tension reduction mechanism 6a, and the second stretching mechanism 8b is provided in the fourth interval R4 downstream of the second tension reduction mechanism 6b. The first stretching mechanism 8a is composed of a first tension adjustment unit 16a, a first tension measuring device 18a, a guide roller 21, and a control device 20. The second stretching mechanism 8b is composed of a fourth tension adjustment unit 16d, a fourth tension measuring device 18d, a guide roller 21, and a control device 20.

[0043] The tensioning mechanism 8 has Figure 4 The uncoated stretching roller 22 is shown. Figure 4 This is a schematic diagram of the uncoated portion stretching roller 22 of the stretching mechanism 8. The uncoated portion stretching roller 22 has a rotating shaft 24 and a support portion 26. The rotating shaft 24 rotates as the electrode plate 100 is conveyed. The support portion 26 is provided on the outer periphery of the rotating shaft 24, supporting the electrode plate 100 while rotating together with the rotating shaft 24. The support portion 26 has a step and abuts only against the uncoated portion 106 of the electrode plate 100. The coated portion 104 is away from the uncoated portion stretching roller 22. If tension is applied to the electrode plate 100 in this state by the first tension adjustment portion 16a or the fourth tension adjustment portion 16d, the uncoated portion 106 is pressed and stretched by the support portion 26. On the other hand, since the coated portion 104 is not pressed by the support portion 26, the stretching amount is smaller compared to the uncoated portion 106.

[0044] In the first tensioning mechanism 8a, the tension adjusting roller or guide roller 21 constituting the first tension adjusting section 16a is composed of an uncoated tensioning roller 22. Similarly, in the second tensioning mechanism 8b, the tension adjusting roller or guide roller 21 constituting the fourth tension adjusting section 16d is composed of an uncoated tensioning roller 22. Furthermore, from the viewpoint of maintaining the accuracy of tension measurement, it is preferable that the guide roller 21 (the roller with a force sensor) equipped with the first tension measuring device 18a or the fourth tension measuring device 18d is not used as an uncoated tensioning roller 22.

[0045] The inventors conducted in-depth research and discovered that if the coating section 104 is compressed by the compression roller 4 while the electrode plate 100 is under tension, the substrate 102 constituting the coating section 104 may be overstretched and break. In particular, in recent years, due to the increasing energy density requirements of batteries, there has been a trend towards increasing the coating amount of electrode paste and increasing the thickness of the electrode active material layer 108. If the thickness of the electrode active material layer 108 increases, a greater force will be applied to the substrate 102 when the coating section 104 is compressed by the compression roller 4, causing further stretching of the substrate 102.

[0046] In contrast, by arranging a tension reduction mechanism 6 between each stretching mechanism 8 and the compression roller 4, it is possible to suppress the transmission of tension applied to the electrode plate 100 in each stretching mechanism 8 to the portion of the electrode plate 100 held by the compression roller 4. As a result, the tension applied to the portion of the electrode plate 100 held by the compression roller 4 can be reduced, and the possibility of the substrate 102 breaking due to excessive stretching can be suppressed.

[0047] In this embodiment, tension reduction mechanisms 6 are provided on both the upstream and downstream sides of the compression roller 4, but it is not limited to this. If the tension reduction mechanism 6 is provided on at least one of the upstream and downstream sides of the compression roller 4, the stretching of the substrate 102 can be suppressed compared to the case where neither is provided.

[0048] Figure 5 This is a diagram showing the relationship between the presence or absence of the first tension reducing mechanism 6a and the second tension reducing mechanism 6b and the elongation of the coating section 104. The reference example is a manufacturing apparatus that does not include either the first tension reducing mechanism 6a or the second tension reducing mechanism 6b. Example 1 is a manufacturing apparatus that includes only the second tension reducing mechanism 6b. That is, an embodiment in which the tension caused by the first stretching mechanism 8a is transmitted from the upstream side of the compression roller 4 to the electrode plate 100. Example 2 is a manufacturing apparatus that includes only the first tension reducing mechanism 6a. That is, an embodiment in which the tension caused by the second stretching mechanism 8b is transmitted from the downstream side of the compression roller 4 to the electrode plate 100.

[0049] Example 3 is a manufacturing apparatus including a first tension reduction mechanism 6a and a second tension reduction mechanism 6b. That is, an embodiment in which the tension caused by the stretching mechanism 8 is not transmitted to the electrode plate 100 from either the upstream or downstream side of the compression roller 4. Furthermore, the manufacturing apparatus of the reference example and each embodiment includes a first stretching mechanism 8a and a second stretching mechanism 8b. The "elongation of the coating portion" on the longitudinal axis is the ratio of the length of the compressed coating portion 104 to the length of the uncompressed coating portion 104 in each manufacturing apparatus. The elongation of the coating portion 104 is obtained by scribing lines on the coated portion 104 and the uncoated portion 106, and measuring the length between the lines using a metal ruler or a magnifying microscope before and after compression.

[0050] like Figure 5 As shown, in the manufacturing apparatus of Examples 1 to 3, the elongation of the coating section 104 is lower than that of the manufacturing apparatus of the reference example. Based on this, it can be seen that if the tension reduction mechanism 6 is provided on at least one of the upstream and downstream sides of the compression roller 4, the stretching of the coating section 104 can be suppressed, thereby suppressing the breakage of the electrode plate 100. Furthermore, based on the results of Examples 1 and 2, it is known that when the tension reduction mechanism 6 is provided only on either the upstream or downstream side of the compression roller 4, providing the tension reduction mechanism 6 on the upstream side can more effectively suppress the breakage of the electrode plate 100.

[0051] Furthermore, based on the results of Example 3, it was confirmed that when tension reduction mechanisms 6 are provided on both the upstream and downstream sides of the compression roller 4, the stretching of the coating section 104 is most effectively suppressed, thereby most effectively suppressing the breakage of the electrode plate 100. Moreover, even when the stretching mechanism 8 is not provided on the conveyor line 2, considerable tension is applied to the electrode plate 100 during conveying. Therefore, even without the stretching mechanism 8, the breakage suppression effect of the electrode plate 100 based on the tension reduction mechanism 6 is obtained.

[0052] As described above, the manufacturing apparatus 1 for the electrode plate 100 of this embodiment includes: a conveyor line 2 for conveying the electrode plate 100 having a coated portion 104 and an uncoated portion 106; a compression roller 4 disposed on the conveyor line 2 to compress the coated portion 104; and a tension reduction mechanism 6 disposed on at least one of an upstream section (second section R2) terminating at the compression roller 4 and a downstream section (third section R3) beginning at the compression roller 4 in the conveyor line 2 to reduce the tension applied to the electrode plate 100. By providing a tension reduction section on at least one of the section extending upstream from the compression roller 4 and the section extending downstream from the compression roller 4, it is possible to suppress the stretching of the substrate 102 when the coated portion 104 is compressed by the compression roller 4. As a result, the possibility of electrode plate breakage can be reduced, and the electrode plate 100 can be manufactured more stably.

[0053] Furthermore, the tension reduction mechanism 6 of this embodiment is provided in both the upstream and downstream sections of the compression roller 4. This further suppresses the stretching of the substrate 102. Therefore, the electrode plate 100 can be manufactured more stably.

[0054] Furthermore, in this embodiment, the manufacturing apparatus 1, located away from the compression roller 4 in the conveyor line 2, includes a stretching mechanism 8 for stretching the uncoated portion 106. This reduces the deviation between the length of the coated portion 104 and the length of the uncoated portion 106, suppressing wrinkles in the electrode plate 100. Therefore, the electrode plate 100 can be manufactured more stably.

[0055] Furthermore, in this embodiment, the stretching mechanism 8 is provided on both the upstream and downstream sides of the compression roller 4. This allows for stretching of the uncoated portion 106 in two stages. Consequently, it is possible to suppress deformation of the electrode plate 100 or an increase in the load applied to the electrode plate 100 due to the stretching process of the uncoated portion 106. Therefore, the electrode plate 100 can be manufactured more stably.

[0056] Furthermore, the conveyor line 2 of this embodiment has a conveying mechanism 14 that holds or adsorbs the coating portion 104 and conveys the electrode plate 100. As a result, wrinkles can be suppressed in the uncoated portion 106, and the electrode plate 100 can be manufactured more stably.

[0057] Furthermore, in this embodiment, the manufacturing apparatus 1 satisfies a / b ≥ 0 when the dimension of the width direction B of the portion of the coating section 104 held or attracted by the conveying mechanism 14, which is orthogonal to the conveying direction A of the electrode plate 100, is set as a, and the dimension of the width direction B of the coating section 104 is set as b. This suppresses wrinkling of the uncoated portion 106 and prevents a decrease in the conveying speed of the electrode plate 100.

[0058] The embodiments of this disclosure have been described in detail above. The above embodiments are merely examples illustrating specific ways of implementing this disclosure. The content of the embodiments does not limit the technical scope of this disclosure; various design changes, such as alterations, additions, and deletions of constituent elements, can be made within the scope of the spirit of this disclosure as defined by the claims. New embodiments with applied design changes possess the effects of both the combined embodiments and their variations. In the above embodiments, the content enabling such design changes is emphasized by markings such as "in this embodiment" or "in this embodiment," but design changes are also permitted even without such markings. Any combination of constituent elements included in each embodiment is also valid as a form of this disclosure. The shaded lines marked on the cross-sections of the drawings are not intended to limit the material of the objects marked with shaded lines.

[0059] The invention described above can also be specified by the items described below.

[0060] [Project 1]

[0061] A method for manufacturing an electrode plate (100) includes the following steps:

[0062] The electrode plate (100) is provided with a coated portion (104) on the surface of a substrate (102) coated with an electrode active material and an uncoated portion (106) on the surface of the substrate (102) where no electrode active material is coated.

[0063] The coating section (104) of the conveyed electrode plate (100) is compressed; and

[0064] In at least one of the upstream section ending at the compression position and the downstream section beginning at the compression position, the tension applied to the electrode plate (100) is reduced.

[0065] [Industrial Availability]

[0066] This disclosure can be used for an apparatus for manufacturing electrode plates and a method for manufacturing electrode plates.

[0067] [Explanation of reference numerals in the attached figures]

[0068] 1 Manufacturing apparatus, 2 Conveyor line, 4 Compression roller, 6 Tension reduction mechanism, 8 Stretching mechanism, 14 Conveying mechanism, 100 Electrode plate, 102 Substrate, 104 Coating section, 106 Uncoated section.

Claims

1. An apparatus for manufacturing an electrode plate, comprising: An electrode plate conveying line, wherein the electrode plate has a coated portion on the surface of a substrate coated with an electrode active material and an uncoated portion on the surface where the electrode active material is not coated. A compression roller, located on the conveyor line, compresses the coating section. A tension reduction mechanism, located in at least one of the upstream section terminating at the compression roller and the downstream section beginning at the compression roller in the conveyor line, reduces the tension applied to the electrode plate. A stretching mechanism, located in the conveyor line further away from the compression roller than the tension reducing mechanism, applies a higher tension to the uncoated portion than the tension applied to the electrode plate during the tension reduction period by the tension reducing mechanism, thereby stretching the uncoated portion. The conveyor line has an unwinding device and a winding device. The unwinding device feeds the electrode plate that has not undergone the compression treatment of the coating section by the compression rollers to the downstream side of the conveyor line, and the winding device retrieves the electrode plate that has undergone the compression treatment. The tension reduction mechanism and the stretching mechanism are disposed in at least one interval between the unwinding device and the compression roller and between the compression roller and the winding device.

2. The manufacturing apparatus as described in claim 1, The tension reduction mechanism is located in both the upstream and downstream sections.

3. The manufacturing apparatus as described in claim 1, The stretching mechanism is located on both the upstream and downstream sides of the compression roller.

4. The manufacturing apparatus as described in claim 1 or 3, The conveyor line has a conveying mechanism that holds or adsorbs the coating section to convey the electrode plate.

5. The manufacturing apparatus as described in claim 4, When the dimension of the portion of the coating section held or attracted by the conveying mechanism in the width direction orthogonal to the conveying direction of the electrode plate is defined as 'a', and the dimension of the coating section in the width direction is defined as 'b',... The condition a / b ≥ 0.4 is satisfied.

6. A method for manufacturing an electrode plate, comprising the following steps: The electrode plate is conveyed from the unwinding position to the winding position. The electrode plate has a coated portion on the surface of the substrate to which an electrode active material is coated, and an uncoated portion on the surface to which the electrode active material is not coated. The coating section of the conveyed electrode plate is compressed. In at least one of the upstream section ending at the compression position and the downstream section beginning at the compression position, the tension applied to the electrode plate is reduced. At a position further away from the compression position than the range where the tension applied to the electrode plate is reduced, a higher tension than the tension applied to the electrode plate during the reduced tension range is applied to the uncoated portion, thereby stretching the uncoated portion. In at least one interval between the unwinding position and the compression position, and between the compression position and the winding position, the tension reduction and the stretching of the uncoated portion are performed independently of the unwinding and winding of the electrode plate.

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