Device for manufacturing electrode, method for manufacturing electrode, and battery

Abstract

A device (1) for manufacturing an electrode is provided with a supply unit (10), an opposing unit (20), a guide unit (30), and a flow path defining unit (60). The supply unit (10) supplies powder to a sheet-shaped base material (2). The opposing unit (20) extends in the width direction of the base material (2), the direction being substantially orthogonal to a conveyance direction in which the base material (2) is conveyed. The opposing unit (20) presses the powder supplied by the supply unit (10) against the base material (2). The guide unit (30) is disposed further on the upstream side in a conveyance direction DR1 than the opposing unit (20), and guides powder P supplied from the supply unit (10) to the base material (2). The flow path defining unit (60) is provided between the opposing unit (20) and the guide unit (30), and defines a flow path for the powder P present between the opposing unit (20) and the guide unit (30).

Description

Electrode manufacturing apparatus, electrode manufacturing method, and battery

[0001] The present invention relates to an electrode manufacturing apparatus, an electrode manufacturing method, and a battery.

[0002] A technique for pressing a powder material onto a substrate using a rolling roll is disclosed in, for example, Patent Document 1.

[0003] JP 2012-214854 A

[0004] The powder material supplied to the substrate as described in Patent Document 1 is not uniformly pressed onto the substrate with the same thickness. Therefore, it is required to press the powder material onto the substrate as uniformly as possible.

[0005] One object of the present invention is to uniformly compress powder onto a substrate.

[0006] The invention described in claim 1 is an electrode manufacturing apparatus comprising: a supply section that supplies powder to a sheet-like substrate; an opposing section that extends in the width direction of the substrate, approximately perpendicular to the transport direction in which the substrate is transported, and presses the powder supplied by the supply section against the substrate; a guide section that is arranged upstream of the opposing section in the transport direction and guides the powder supplied from the supply section to the substrate; and a flow path setting section that is provided between the opposing section and the guide section and sets a flow path for the powder that exists between the opposing section and the guide section.

[0007] A seventh aspect of the present invention is a battery having an electrode manufactured using the electrode manufacturing apparatus according to the first or second aspect of the present invention.

[0008] According to the above aspect of the present invention, the powder can be uniformly compressed onto the substrate.

[0009] 1 is a schematic cross-sectional view of an electrode manufacturing apparatus according to a first embodiment; FIG. 2 is an enlarged schematic cross-sectional view of part A shown in FIG. 1; FIG. 3 is a schematic plan view of the manufacturing apparatus shown in FIG. 2 as viewed from above; FIG. 4 is a schematic plan view showing the state of the adjustment unit when the pivot unit is open outward in the width direction; FIG. 5 is a graph plotting the relationship between the amount of powder at the end and the pivot angle; FIG. 6 is a schematic cross-sectional view of the manufacturing apparatus for an electrode according to a second embodiment; FIG. 7 is a plan view of the manufacturing apparatus shown in FIG. 6 as viewed from above; FIG. 8 is a schematic cross-sectional view of an electrode manufacturing apparatus in a modified example; FIG. 9 is a plan view of the manufacturing apparatus shown in FIG. 8 as viewed from above; FIG. 10 is a schematic cross-sectional view of a manufacturing apparatus for an electrode according to a third embodiment; FIG. 11 is a schematic cross-sectional view of a pressing step performed after the first to third embodiments; FIG. 12 is a flowchart of a manufacturing method of an electrode; FIG. 13 is a schematic cross-sectional view of an electrode manufacturing apparatus according to a fourth embodiment; FIG. 14 is a schematic cross-sectional view showing an example of a flow path setting unit as viewed from the width direction of a substrate; FIG. 15 is a schematic cross-sectional view of an example of a flow path setting unit as viewed from the width direction of a substrate; FIG. 16 is a schematic view of the flow path setting unit as viewed from the transport direction of a substrate; 1 is a schematic diagram of a flow path setting unit as viewed from the transport direction of a substrate, FIG. 2 is a schematic cross-sectional view showing an example of a flow path setting unit as viewed from the width direction of a substrate, and FIG. 3 is a schematic diagram of an electrode manufacturing apparatus including a flow path setting unit as viewed from above.

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, similar components are designated by similar reference numerals, and the description thereof will be omitted as appropriate.

[0011] <First embodiment> (Electrode manufacturing apparatus 1) Fig. 1 is a schematic cross-sectional view of an electrode manufacturing apparatus 1 according to a first embodiment. Fig. 2 is an enlarged schematic cross-sectional view of portion A shown in Fig. 1 . The manufacturing apparatus 1 will be described with reference to Figs. 1 and 2. The manufacturing apparatus 1 is an apparatus for manufacturing electrodes to be used in batteries. In the first embodiment, a sheet-like substrate 2 is used to manufacture positive and negative electrodes of the battery. In the first embodiment, the manufacturing apparatus 1 conveys the substrate 2, to which an adhesive layer 3 (e.g., an undercoat) has been applied, in a conveying direction DR1, and adheres powder P, described below, to the adhesive layer 3 (substrate 2), followed by pressure bonding using a pair of press rolls 90, thereby manufacturing an electrode.

[0012] (Supplying Unit 10) As shown in FIG. 2, the manufacturing apparatus 1 includes a supplying unit 10, an opposing unit 20, and a guide unit 30. The supplying unit 10 according to the first embodiment has a housing in which powder P is stored. The powder P according to the first embodiment is a granulated material, and the particle size of the granulated material is 15 μm or more and 110 μm or less. More preferably, it is in the range of 60 μm ± 30 μm. The supplying unit 10 supplies the powder P to the substrate 2 being transported.

[0013] (Facing portion 20) The facing portion 20 according to the first embodiment has a cylindrical or columnar shape. The facing portion 20 has a shape extending in the width direction DR2 of the substrate 2. The width direction DR2 is a direction substantially perpendicular to the conveying direction DR1 in which the substrate 2 is conveyed, and is the width direction of the substrate 2. In this specification, the conveying direction DR1 and the width direction DR2 being substantially perpendicular to each other means that the angle between the conveying direction DR1 and the width direction DR2 is between -5° and 5°. The roll-shaped facing portion 20 rotates in the direction opposite to the conveying direction DR1 in a plane perpendicular to the width direction DR2.

[0014] In the first embodiment, the facing unit 20 faces the press roll 90 via the substrate 2. The facing unit 20 presses the powder P supplied by the supply unit 10 against the substrate 2. The facing unit 20 presses the powder P against the substrate 2, thereby making the thickness of the powder P adhering to the substrate 2 uniform.

[0015] (Guide section 30) In the first embodiment, the guide section 30 has a plate-like shape. The guide section 30 guides the powder P supplied from the supply section 10 to the substrate 2 being transported in the transport direction DR1. The powder P is carried along the surface of the guide section 30 to the substrate 2 being transported. The guide section 30 is arranged upstream of the facing section 20 in the transport direction DR1. The guide section 30 is arranged upstream of the supply section 10 in the transport direction DR1.

[0016] (Adjustment unit 40) Figure 3 is a schematic plan view of the manufacturing apparatus 1 shown in Figure 2 when viewed from above. Note that the supply unit 10 and the guide unit 30 are omitted from Figure 3. The manufacturing apparatus 1 according to the first embodiment further includes an adjustment unit 40. The adjustment unit 40 is provided at the end 21 of the opposing unit 20 in the width direction DR2, and adjusts the amount of powder P guided to the end 21.

[0017] In the first embodiment, the adjustment unit 40 may include a hinge 41, a plate-shaped rotating unit 42, and a plate-shaped fixed unit 43. The fixed unit 43 is provided at the end 21. The rotating unit 42 is rotatable via the hinge 41 in the direction in which the fixed unit 43 extends (the conveying direction DR1). In FIG. 3 , the rotating unit 42 is rotated toward the inside in the width direction DR2 by a rotation angle of θ1. In this way, the adjustment unit 40 according to the first embodiment is configured to be rotatable in the conveying direction DR1.

[0018] 4 is a schematic plan view showing the state of the adjustment unit 40 when the rotation unit 42 is open toward the outside in the width direction DR2. The adjustment unit 40 according to the first embodiment may adjust the amount of powder P guided to the end portion 21 in accordance with the amount of powder P covering the substrate 2. Specifically, the adjustment unit 40 may adjust the amount of powder P guided near the end portion 21 in accordance with so-called deposition (the amount of powder P per unit area on the surface of the substrate 2) near the end portion 21. That is, the adjustment unit 40 according to the first embodiment may adjust the angle at which the rotation unit 42 rotates in accordance with the deposition near the end portion 21.

[0019] For example, as shown in FIG. 4 , when the rotating unit 42 opens at a rotation angle θ2 toward the outside in the width direction DR2, a large amount of powder P is guided to the end portion 21. For example, as shown in FIG. 3 , when the rotating unit 42 opens at a rotation angle θ1 toward the inside in the width direction DR2, a small amount of powder P is guided to the end portion 21. In this manner, the adjustment unit 40 may adjust the angle at which the rotating unit 42 opens to adjust the amount of powder P guided to the end portion 21. If the rotation angle θ in the direction in which the rotating unit 42 closes toward the inside in the width direction DR2 is defined as positive and the rotation angle in the direction in which the rotating unit 42 opens toward the outside in the width direction DR2 is defined as negative, the range of the rotation angle θ of the rotating unit 42 is preferably −1.0°≦θ≦1.0°.

[0020] (Effects) As described above, the manufacturing apparatus 1 according to the first embodiment includes the supply unit 10, the facing unit 20, and the adjustment unit 40. The adjustment unit 40 is provided at the end 21 of the facing unit 20 in the width direction DR2 and adjusts the amount of powder P guided to the end 21. Generally, the deposition (amount of powder per unit area on the surface of the substrate) near the end of the facing unit varies more significantly than in areas other than the end of the facing unit. However, in the first embodiment, the provision of the adjustment unit 40 makes it possible to adjust the amount of powder P guided to the end 21, thereby suppressing the deposition variation near the end 21 of the facing unit 20. This allows the powder P to be evenly adhered to the substrate 2. Therefore, the powder P can be uniformly compressed onto the substrate 2.

[0021] Furthermore, the adjustment unit 40 may be configured to be rotatable with respect to the conveyance direction DR1, which makes it possible to easily configure a mechanism for adjusting the amount of powder P guided to the end portion 21.

[0022] Furthermore, the adjustment unit 40 may adjust the amount of powder P guided to the end portion 21 in accordance with the amount of powder P covering the substrate 2. By measuring the amount (deposition) of powder P covering the substrate 2 and adjusting the amount of powder P guided to the end portion 21, the powder P can be adhered to the substrate 2 more accurately and evenly.

[0023] Examples will be described below. In order to calculate the range of an appropriate rotation angle θ, evaluation was performed under the following conditions.

[0024] <Implementation conditions> The rotation angle θ in the direction of closing toward the inside in the width direction (θ1 in FIG. 3) was defined as positive, and the rotation angle θ in the direction of opening toward the outside in the width direction DR2 (θ2 in FIG. 4) was defined as negative, and the relationship between the rotation angle θ and the amount of powder near the end was evaluated.

[0025] <Evaluation Results> Figure 5 is a graph plotting the relationship between the amount of powder at the end and the rotation angle. The horizontal axis of Figure 5 indicates the amount of powder at the end, and the vertical axis indicates the optimal rotation angle of the rotation unit relative to the amount of powder at the end. Note that the "amount of powder at the end" indicates the ratio between the average amount of powder adhering to the substrate as a whole and the amount of powder adhering to the substrate near the end. For example, in the graph of Figure 5, when the amount of powder at the end is 0.9 (90%), this means that the amount of powder near the end is 10% less than the average amount. The graph of Figure 5 also shows that when the amount of powder at the end is 0.9, the optimal rotation angle is approximately -1.0°.

[0026] As an example, as shown in FIG. 5, when the rotation angle θ is −1.0°≦θ≦1.0°, the ratio of the powder amount near the end to the average value is within ±10%. To more precisely control the powder amount, it is preferable to set the rotation angle θ to −0.2°≦θ≦0.2°. When the implementation conditions are different, the optimal powder amount can be obtained by appropriately adjusting the rotation angle, etc. Second Embodiment FIG. 6 is a schematic cross-sectional view of an electrode manufacturing apparatus 1 according to a second embodiment. FIG. 7 is a plan view of the manufacturing apparatus 1 shown in FIG. 6 as viewed from above. Note that the guide unit 30 and the supply unit 10 are omitted in FIG. 7. Unlike the first embodiment, the manufacturing apparatus 1 according to the second embodiment includes a stirring unit 50.

[0027] 6, the stirring unit 50 according to the second embodiment is provided between the facing unit 20 and the guide unit 30. The stirring unit 50 according to the second embodiment rotates to stir the powder P1 present between the facing unit 20 and the guide unit 30. In the second embodiment, the stirring unit 50 rotates counterclockwise.

[0028] As shown in Fig. 7 , the agitation unit 50 according to the second embodiment has a shape that extends in the width direction DR2. The agitation unit 50 according to the second embodiment may include a drive unit 51 and a blade unit 52. The drive unit 51 rotates the blade unit 52 to agitate the powder P. As shown in Fig. 7 , the blade unit 52 may be configured in a direction that directs the powder P inward in the width direction DR2.

[0029] As described above, the manufacturing apparatus 1 according to the second embodiment includes the supply unit 10, the facing unit 20, the guide unit 30, and the stirring unit 50. By providing the stirring unit 50, it is possible to prevent accumulation of powder P from forming in the region R between the facing unit 20 and the guide unit 30. This allows the powder P to adhere evenly to the substrate 2. Therefore, the powder P can be evenly pressed onto the substrate 2.

[0030] Furthermore, the stirring unit 50 may adjust the degree of stirring depending on the amount of powder P covering the substrate 2. More specifically, for example, the rotation speed of the stirring unit 50 may be adjusted depending on the deposition (the amount of powder P per unit area on the surface of the substrate 2). This allows the powder P to be more accurately and uniformly pressed onto the substrate 2.

[0031] (Modification) Fig. 8 is a schematic cross-sectional view of an electrode manufacturing apparatus 1 in a modification. Fig. 9 is a plan view of the manufacturing apparatus 1 shown in Fig. 8 when viewed from above. As shown in Fig. 8, a flat plate 80 may be provided between the press roll 90 and the facing unit 20. The facing unit 20 in the modification may press the plate 80 via the substrate 2 to cause the powder P to adhere to the substrate 2.

[0032] 9, the agitating unit 50 in the modified example may include a plurality of driving units 51. The blade unit 52 in the modified example may have a spiral shape.

[0033] 10 is a schematic cross-sectional view of a manufacturing apparatus 1 according to a third embodiment. Unlike the first embodiment, the manufacturing apparatus 1 according to the third embodiment includes a flow path setting unit 60. The flow path setting unit 60 according to the third embodiment is provided between the opposing portion 20 and the guide portion 30, and sets a flow path for the powder P1 present between the opposing portion 20 and the guide portion 30. The flow path setting unit 60 according to the third embodiment has a plate-like shape extending in the width direction DR2.

[0034] By providing the flow path setting portion 60, the region R between the opposing portion 20 and the guide portion 30 is divided into a region R1 and a region R2. That is, the region R1 is formed between the guide portion 30 and the flow path setting portion 60, and the region R2 is formed between the opposing portion 20 and the flow path setting portion 60.

[0035] Region R1 is a storage section in which powder P supplied from supply section 10 is stored. The powder P supplied from supply section 10 first lands in this storage section. In the vertical direction DR3 (= the direction in which gravity acts, the up-down direction), the height of the upper edge 61 of the flow path setting section is higher than the height of the upper surface 63 of the powder P stored in the storage section (region R1).

[0036] Region R2 is a reverse flow path through which the powder P supplied to the substrate 2 flows backward. The flow of the powder P supplied to the substrate 2 will be described. The supply unit 10 according to the third embodiment first supplies the powder P to the storage unit (region R1). The powder P supplied to region R1 is then transported to the substrate 2 along direction D1. A portion of the powder P transported to the substrate 2 is then transported in the transport direction DR1. Another portion of the powder P transported to the substrate 2 is transported by the opposing unit 20 along direction D2 to the upper edge 61 of the flow path setting unit 60. That is, the powder P flows backward toward the upper edge 61. The powder P that reaches the upper edge 61 then passes over the flow path setting unit 60 and lands on the upper surface 63 (see arrow D3).

[0037] In addition, in a cross section perpendicular to the width direction DR2, the first distance t1 between the flow path setting portion 60 and the facing portion 20 is larger than the second distance t2 between the facing portion 20 and the substrate 2. The first distance t1 is the shortest distance between the flow path setting portion 60 and the facing portion 20. The second distance t2 is the shortest distance between the facing portion 20 and the substrate 2 (adhesive layer 3).

[0038] In addition, in a cross section perpendicular to the width direction DR2, the second distance t2 is smaller than a third distance t3 between the lower edge 62 of the flow path setting portion 60 and the base material 2 (adhesive layer 3) in the vertical direction DR3. The third distance t3 is the shortest distance between the lower edge 62 and the base material 2 (adhesive layer 3).

[0039] As described above, the electrode manufacturing apparatus 1 according to the third embodiment includes the supply unit 10, the facing unit 20, the guide unit 30, and the flow path setting unit 60. By providing the flow path setting unit 60, it is possible to prevent accumulation of powder P in the region R between the facing unit 20 and the guide unit 30. This allows the powder P to be adhered evenly to the substrate 2. Therefore, the powder P can be uniformly pressure-bonded to the substrate 2.

[0040] Furthermore, in the vertical direction DR3, the height of the upper edge 61 of the flow path setting portion 60 may be higher than the height of the upper surface 63 of the powder P stored in the storage portion (region R1). This allows the powder P that has flowed back from the reverse flow path (region R2) to flow again into the storage portion (region R1), thereby making it possible to effectively reuse the powder P.

[0041] Furthermore, the electrode manufacturing apparatus 1 according to the third embodiment may include a suction unit 70 (not shown) that sucks the powder P accumulated in the reverse flow path (region R2). This allows the powder P to be effectively reused without imposing a limit on the height of the upper edge 61 as described above.

[0042] The substrate transport path shown in FIG. 1 is an example. For example, the substrate 2 is unwound from the unwinding section, and transport rolls may be added along the path of the substrate 2 to form a predetermined transport path for the substrate. Transport rolls include, but are not limited to, driven rolls, feed rolls, and suction rolls. The substrate 2 on which the powder P is formed (hereinafter, the substrate 2 on which the powder P is formed may be simply referred to as the substrate 2) may be further pressed by a second press device 100 having second press rolls 100a and 100b, as shown in FIG. 11. The configuration of further pressing by the transport rolls and second press rolls 100a and 100b can also be applied to the first to third embodiments described above.

[0043] The gap between the pair of second press rolls 100a and 100b is, for example, 50 μm to 200 μm, and the diameter of the second press rolls 100a and 100b is, for example, Φ500 mm to Φ800 mm.

[0044] The second press rolls 100a and 100b rotate in the direction of movement of the substrate 2, and further press the powder P pressed by the press roll 90 into the substrate 2. The peripheral speed of the second press rolls 100a and 100b is the same as the traveling speed of the substrate 2, and is, for example, 20 m / min or more and 130 m / min or less.

[0045] The pressure applied to the substrate 2 by the second press rolls 100a and 100b is, for example, 1 ton / cm or more and 5 ton / cm or less. The press roll 90 presses the powder P with a linear pressure higher than that applied by the press roll 90, so that an active material layer of a desired density and a predetermined thickness can be formed. Furthermore, the weight per unit area of ​​the substrate 2 after the active material layers are pressed onto both sides by the second press rolls 100a and 100b is, for example, 10 mg / cm when a negative electrode active material layer is formed. ２ 30mg / cm or more ２ When a positive electrode active material layer is formed, for example, 10 mg / cm ２ 50mg / cm or more ２ The following is the result.

[0046] The material of the second press rolls 100 a, 100 b is not particularly limited, but is preferably one with high abrasion resistance. Specifically, for example, a cylindrical or columnar roll made of SUS material and coated with a coating material can be used, but is not limited to this.

[0047] [Substrate 2] The substrate 2 according to these embodiments is, for example, a general current collector foil. As an example, when the powder P is made of a negative electrode active material, the current collector foil is preferably a foil mainly composed of copper. When the powder P is made of a positive electrode active material, the current collector foil is preferably a foil mainly composed of aluminum. The width of the substrate 2 is not particularly limited, but is, for example, 1,300 mm or less. The length of the substrate 2 is, for example, 50 m or more and 10,000 m or less, but is not limited thereto. The configuration of the substrate 2 described above can also be applied to the first to third embodiments described above.

[0048] [Powder P] As the powder P according to these embodiments, for example, granules obtained by granulating either a negative electrode active material or a positive electrode active material can be used.

[0049] Positive electrode active materials include composite oxides of lithium and transition metals such as lithium-nickel composite oxide, lithium-cobalt composite oxide, lithium-nickel-cobalt-aluminum composite oxide, and lithium-nickel-manganese-cobalt composite oxide (NMC); TiS ２ , FeS, MoS ２ transition metal sulfides such as MnO, V ２ O ５ , V ６ O １３ , TiO ２ and olivine-type lithium phosphates. The positive electrode active material preferably contains a lithium-nickel-manganese-cobalt composite oxide having an average particle size of 3 μm to 15 μm. The above-mentioned compounds may also contain compounds in which some elements are partially substituted with other elements.

[0050] The negative electrode active material may be one or a combination of two or more selected from natural graphite, artificial graphite, hard carbon, soft carbon, carbon black, etc. The natural graphite and artificial graphite may have particle surfaces coated with amorphous carbon, or may be primary particles, particles formed by aggregation of primary particles to form secondary particles, or mixtures of these particles. Silicon-containing SiO, SiO ２ Alternatively, a composite of silicon and carbon may be used, and these may be mixed with carbon.

[0051] The powder P preferably further contains a conductive additive and a binder. The conductive additive may be one or a combination of two or more selected from carbon blacks such as acetylene black and ketjen black, activated carbon, graphite, mesoporous carbon, fullerenes, carbon fibers such as carbon nanotubes, carbon nanofibers, and carbon nanobrushes. The binder may be one or a combination of two or more selected from fluororesins such as PVDF, PTFE, and PVF, conductive polymers such as polyacrylic acid, polyanilines, and polythiophenes, and synthetic rubbers such as SBR.

[0052] Furthermore, when the powder P contains a conductive additive and a binder, it is preferable that the conductive additive be 0.02 parts by mass or more and 5 parts by mass or less, and the binder be 1 part by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the total powder P.

[0053] Furthermore, the particle diameter D50 at 50% cumulative frequency in a volume-based cumulative frequency distribution curve of the powder P measured using a laser diffraction particle size distribution analyzer is preferably 40 μm or more, more preferably 45 μm or more, and even more preferably 50 μm or more. Furthermore, the particle diameter D50 of the powder P is preferably 120 μm or less, more preferably 110 μm or less, even more preferably 100 μm or less, and even more preferably 90 μm or less. The measurement of the D50 is performed, for example, in accordance with JIS Z 8825. The configuration of the powder P described above can also be applied to the first to third embodiments described above.

[0054] Next, a flowchart of the electrode manufacturing method according to these embodiments is shown in FIG. 12. First, powder P is placed on the substrate 2 (step S10). Next, the placed powder P is leveled by the opposing portion 20 (step S20). Next, the leveled powder P is pre-pressed by the press roll 90 (step S30). The substrate 2 is then attached to the second press roll device 100, and the powder P pressed onto both sides is pressed by the press rolls 100a and 100b. Note that steps S10 to S30 are performed on both sides in two separate steps, as opposed to the steps performed on one side at a time in the first and second embodiments. Furthermore, as described above, the configuration of further pressing with the second press roll 100 can also be applied to the first to third embodiments, in which case the steps shown in the flowchart above can be applied.

[0055] Furthermore, the electrodes manufactured by the manufacturing apparatus 1 described in the first to third embodiments can be used to fabricate secondary batteries according to known methods. Specifically, a battery element can be obtained by using the electrode as either a positive or negative electrode plate, and stacking or winding the positive and negative electrodes so that they face each other via a separator. This battery element is housed in a container together with an electrolyte, and one end of a positive terminal electrically connected to the positive electrode plate of the battery element and one end of a negative terminal electrically connected to the negative electrode plate are disposed on the outside of the container. The container can be, but is not limited to, a rectangular or cylindrical metal case made of hard aluminum, iron, or the like, or a film-like pouch case containing aluminum. The electrolytic solution may be any liquid that dissolves the electrolyte, and examples thereof include carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, and vinylene carbonate, lactones such as γ-butyrolactone, ethers, sulfoxides, oxolanes, nitrogen-containing compounds, organic acid esters, and sultones such as 1,3-propane sultone and 1,4-butane sultone, but are not limited thereto. These may be used alone or in combination of two or more. The electrolyte is LiPF ６ , LiBF ６ , LiFSI, etc. Examples of the separator include, but are not limited to, those in the form of membrane, film, nonwoven fabric, etc., including polypropylene, polyethylene, aromatic polyamide, etc.

[0056] Fourth Embodiment Next, a fourth embodiment will be described. Fig. 13 is an example of a schematic plan view of an electric foil manufacturing apparatus 1 according to this embodiment, as viewed from the side of the substrate 2, i.e., from the direction DR2.

[0057] 13 , the facing unit 20 may be located farther away from the supply unit 10. Specifically, when viewed from the DR2 direction, the facing unit 20 may be located farther away from the supply unit 10 within a range in which the facing unit 20 does not come into contact with either of the pair of press rolls 90, with respect to the DR3 direction, which is a line connecting the center of the facing unit 20 and the center of the press roll 90.

[0058] Furthermore, in this embodiment, the rotation speed of the facing portion 20 may be 0% or more and -10% or less of the traveling speed of the substrate 2. The minus sign here means that the traveling direction of the substrate 2 is opposite to the traveling direction of the surface of the facing portion 20 that faces the substrate 2. The configuration regarding the rotation of the facing portion 20 described above can also be applied to the first to third embodiments described above.

[0059] Next, the flow path setting portion 60 in this embodiment will be described. Fig. 14 shows a first example of the flow path setting portion 60 as seen from the direction DR2. In Fig. 14, for convenience of explanation, the flow path setting portion 60 is depicted as a rectangle, but this is not limited thereto. Each vertex of the flow path setting portion 60 does not need to be an acute angle, such as by being chamfered, and each corner may be rounded, each surface may be curved, and the shape may follow the shape of the opposing portion 20 as shown in Fig. 13, and the flow path setting portion 60 is disposed along the width direction DR2.

[0060] In this embodiment, the flow path setting section 60 is provided between the opposing section 20 and the guide section 30, as in the third embodiment, and sets a flow path for the powder P1 present between the opposing section 20 and the guide section 30. The flow path setting section 60 may be inclined at an angle of 30° or less from the vertical direction. The flow path setting section 60 may be flat or may be curved. The upper edge 61 of the flow path setting section 60 is an inclined surface that slopes downward from the horizontal plane in the direction opposite to the movement direction of the substrate 2 (i.e., toward the upstream side). This allows the powder P to move more easily beyond the flow path setting section 60 toward the supply section 10. The angle θ of the inclined surface with respect to the horizontal direction is not particularly limited as long as the powder falls upstream, but is preferably between 0° and 45°, and more preferably between 10° and 45°.

[0061] The first distance t1 between the flow path setting section 60 and the facing section 20 does not need to be constant, but only needs to be such that powder that cannot pass through the second distance t2 between the facing section 20 and the substrate 2 does not get stuck between the flow path setting section 60 and the facing section 20. Preferably, the first distance t1 is adjusted alone or together with the rotation speed of the facing section 20 so that a flow is generated that allows powder that cannot pass through the second distance t2 between the facing section 20 and the substrate 2 to pass over the flow path setting section 60 and fall upstream. The third distance t3 between the lower edge 62 of the flow path setting section 60 and the substrate 2 is not particularly limited, but is preferably equal to or greater than the second distance t2.

[0062] The lower edge 62 of the flow path setting portion 60 is preferably parallel to the substrate 2. However, this is not limited to the case where the lower edge 62 has a shape that follows the opposing portion 20 as shown in FIG.

[0063] Furthermore, the height of the flow path setting section 60 in the DR3 direction, i.e., the vertical distance W1 from the lower end to the upper end of the flow path setting section 60, is not particularly limited, and may be adjusted either alone or together with the rotation speed of the opposing section 20 so that powder located within the first distance t1 between the flow path setting section 60 and the opposing section 20 falls upstream over the upper end of the flow path setting section. The thickness W2 of the flow path setting section 60 in the DR1 direction is not particularly limited, and may be such that it is not deformed by the pressure from the powder; for example, when acrylic is used, the thickness W2 is 3 mm to 10 mm.

[0064] Next, FIG. 15 shows a second example of a flow path setting section 60 as viewed from the DR2 direction. For ease of explanation, FIG. 15 also depicts the vertices of the flow path setting section as acute, right, or obtuse angles. However, as in FIG. 14 , each vertex may be chamfered, each corner may be rounded, each surface may be curved, or the shape may conform to the opposing surface as shown in FIG. 13 . As shown in FIG. 15 , the upper portion of the flow path setting section 60 includes a step portion 65 and an inclined portion 64 upstream of the step portion 65. The upper edge 61 of the inclined portion 64 is an inclined surface. The step portion 65 includes the upper end of the flow path setting section 60 and is narrower in thickness in the direction of travel of the substrate 2 than the other portions of the flow path setting section 60. The upper surface of the step portion 65 is horizontal or inclined so that powder falls toward the upstream side. The inclined portion 64 connects the lower end of the step portion 65 to the other portions of the flow path setting section 60. The inclination direction of the inclined surface of the inclined portion 64 is the same as the inclination direction of the upper edge 61 of the flow path setting portion 60 shown in Figure 14. The angle of the inclined portion 64 with respect to the parallel direction may be such that the upstream side is lower, and is preferably greater than the angle of the upper surface of the stepped portion 65 with respect to the horizontal direction. This makes it easier for powder to fall to the upstream side even when the flow path setting portion is tilted with respect to the vertical direction. The thickness W3 of the stepped portion 65 in the direction of travel of the substrate 2, i.e., in the DR1 direction, is not particularly limited, and may be such that it is not deformed by the pressure received from the powder.

[0065] Next, FIG. 16 shows an example of a flow path setting section 60 as viewed from the DR1 direction, corresponding to the flow path setting section 60 in FIG. 14 . However, FIG. 16 is a schematic diagram of the configuration when the upper surface of the flow path setting section in FIG. 14 is substantially horizontal (the angle θ in FIG. 14 is almost 0°). The flow path setting section 60 shown in FIG. 16 has a concave shape as viewed from the DR1 direction. In other words, the upper edge 61 of the flow path setting section 60 has a region in which its height decreases as it approaches an arbitrary reference point O (the center in the DR2 direction in the example shown in FIG. 16 ), which is a part of the upper edge 61, in the width direction of the substrate 2 as viewed from the DR1 direction. Hereinafter, this shape will be referred to as a concave shape. This prevents the powder P from collecting at the edge of the substrate 2.

[0066] The position of the reference point O is not limited to the center in the DR2 direction and may be shifted from the center. However, in the width direction of the substrate 2, the distance between the reference point O and the center of the substrate 2 is ⅓ or less, preferably ⅕ or less, of the width of the substrate 2. The difference W5 between the height of the highest position (the end in FIG. 16 ) of the flow path setting section 60 and the height of the reference point O is, for example, 0.5 mm or more and 20 mm or less.

[0067] Next, Fig. 17 shows another example of a flow path setting portion 60 viewed from the direction DR1, corresponding to the flow path setting portion 60 in Fig. 14. However, Fig. 17 is a schematic diagram showing a configuration in which the upper edge of the flow path setting portion in Fig. 14 is not horizontal. The upper edge 61 of the flow path setting portion 60 has a concave shape when viewed from the direction DR1, similar to Fig. 16. Furthermore, Fig. 17 shows the slope of the upper edge 61.

[0068] 18(a) shows the A-A' cross section, which is a cross section at a position outside the reference point O in FIG. 17, and FIG. 18(b) shows the B-B' cross section, which is a cross section at the reference point O. As shown in FIG. 18, the inclination angle θ1 of the upper edge 61 in the A-A' cross section is larger than the inclination angle θ2 of the upper edge 61 in the B-B' cross section outside the reference point O. Furthermore, the downstream height W1 and the upstream height W1' in the A-A' cross section are higher than the downstream height W1 and the upstream height W1' in the B-B' cross section, respectively. However, the inclination angle θ2 may be larger than the inclination angle θ1. Furthermore, the inclined surface may be a curved surface in the cross section.

[0069] According to the above structure, the powder P that passes over the flow path setting portion 60 can be moved toward the reference point O.

[0070] Next, FIG. 19 shows an example of a flow path setting section 60 viewed from the DR1 direction, corresponding to the flow path setting section 60 in FIG. 15 . In FIG. 19 , an inclined portion 64 and a stepped portion 65 are illustrated. The vertical upper edge of the stepped portion 65 is horizontal with respect to the DR2 direction. This ensures that the height of the powder P located within the first distance t1 between the flow path setting section 60 and the facing portion 20 is constant. In other words, the force exerted by the weight of the powder P located within the first distance t1 on the gap between the facing portion 20 and the substrate is constant, allowing the powder P to be stably transferred to the substrate. Meanwhile, the inclined portion 64 shown in FIG. 19 is inclined so that its vertical height decreases toward the reference point O, allowing the powder P to flow more toward the center, preventing the powder P from concentrating at the edge of the substrate 2. FIG. 20(a) shows the A-A' cross section, which is a cross section at a position outside the reference point O in FIG. 19 , and FIG. 20(b) shows the B-B' cross section, which is a cross section at the reference point O. As shown in FIG. 20 , the inclination angle θ1 of the upper edge 61 of the inclined portion 64 in the A-A′ cross section may be larger than the inclination angle θ2 of the upper edge 61 of the inclined portion 64 in the B-B′ cross section. Furthermore, the height W1′ on the upstream side in the A-A′ cross section is higher than the height W1′ on the upstream side in the B-B′ cross section. Meanwhile, the height W1 on the downstream side is the same in the A-A′ cross section and the B-B′ cross section. Furthermore, the height W4 of the step portion 65 in the A-A′ cross section is lower than the height W4 of the step portion 65 in the B-B′ cross section. However, the inclination angle θ2 may be larger than the inclination angle θ1. The inclined surface may be a curved surface in cross section.

[0071] Next, a third example of the flow path setting unit 60 will be described. FIG. 21 is a schematic diagram of an electrode manufacturing apparatus 1 including a flow path setting unit 60 according to a third example of this embodiment, viewed from the DR3 direction, i.e., from above. As shown in FIG. 21 , the flow path setting unit 60 is curved in a top view so that the position of an arbitrary reference point O2 is located toward the supply unit 10. In other words, the reference point O2 is located at the most downstream side, and the outer edges are more upstream. This also prevents the powder P from concentrating at the end of the substrate 2. Note that the position of the reference point O2 is not limited to the center in the DR2 direction and may be offset from the center. The difference W6 between the end of the flow path setting unit 60 and the reference point O2 of the flow path setting unit 60 in the DR1 direction is not particularly limited, but is, for example, 1 mm to 20 mm, and may be 10 mm to 20 mm. Furthermore, the flow path setting unit 60 in this example may have the configurations of the first and second examples described above.

[0072] 21 , the flow path setting section 60 and the opposing section 20 are fixed by a pair of side walls 45. Furthermore, the side walls 45 cover at least a portion of the substrate 2 when viewed from the direction DR3. Powder P (not shown in FIG. 21 ) is placed at a position between the pair of side walls 45 of the substrate 2. In other words, the width of the position where the powder P is placed is determined by the distance between the pair of side walls 45. However, the adjustment section 40 in the first embodiment may be configured together with the pair of side walls 45.

[0073] As described above, the electrode manufacturing apparatus 1 according to this embodiment can prevent the powder P from accumulating in front of the facing portion 20. Furthermore, the powder P can be prevented from gathering at the end of the substrate 2.

[0074] Furthermore, the electrode manufactured by the manufacturing apparatus 1 described in the fourth embodiment can be used to manufacture a secondary battery in accordance with a known method, similar to the electrodes manufactured by the manufacturing apparatus 1 described in the first to third embodiments.

[0075] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0076] In the embodiment, the facing portion 20 may have a plate-like shape instead of a cylindrical or columnar shape.

[0077] In the first embodiment, the electrode manufacturing apparatus 1 may further include a stirring unit 50 in addition to the adjusting unit 40 .

[0078] In the first embodiment, the electrode manufacturing apparatus 1 may further include a flow path setting unit 60 in addition to the adjustment unit 40 .

[0079] Examples of reference forms are given below. 1. An electrode manufacturing apparatus comprising: a supply unit that supplies powder to a sheet-like substrate; an opposing unit that extends in a width direction of the substrate that is approximately perpendicular to a conveying direction in which the substrate is conveyed and that presses the powder supplied by the supply unit against the substrate; a guide unit that is arranged upstream of the opposing unit in the conveying direction and guides the powder supplied from the supply unit to the substrate; and a flow path setting unit that is provided between the opposing unit and the guide unit and sets a flow path for the powder that exists between the opposing unit and the guide unit. 2. An electrode manufacturing apparatus according to 1., wherein, in a cross section perpendicular to the width direction, a first distance between the flow path setting unit and the opposing unit is larger than a second distance between the opposing unit and the substrate. 3. 1. or 2. 3. An electrode manufacturing apparatus according to any one of items 1. to 4., wherein a storage section is formed between the guide section and the flow path setting section in which the powder supplied from the supply section is stored, and the height of an upper edge of the flow path setting section in the vertical direction is higher than the height of an upper surface of the powder stored in the storage section. 4. An electrode manufacturing apparatus according to any one of items 1. to 3., wherein in a cross section perpendicular to the width direction, a second distance between the opposing section and the substrate is smaller than a third distance between a lower edge of the flow path setting section and the substrate in the vertical direction. 5. An electrode manufacturing apparatus according to any one of items 1. to 4., wherein a reverse flow path is formed between the flow path setting section and the opposing section in which the powder supplied to the substrate flows reversely, and the electrode manufacturing apparatus further comprises a suction section that suctions the powder accumulated in the reverse flow path. 6. An electrode manufacturing apparatus according to any one of items 1. to 5., wherein the opposing section has a cylindrical or columnar shape. 7. 1. 6. A battery having an electrode manufactured using the electrode manufacturing apparatus according to any one of the above items 1 to 5.

[0080] This application claims priority based on Japanese Patent Application No. 2024-005493 filed on January 17, 2024, and Japanese Patent Application No. 2024-105538 filed on June 28, 2024, the disclosures of which are incorporated herein in their entireties.

[0081] REFERENCE SIGNS LIST 1 Manufacturing apparatus 2 Substrate 3 Adhesive layer 10 Supply section 20 Opposing section 21 End section 30 Guide section 40 Adjustment section 41 Hinge 42 Rotating section 43 Fixing section 50 Stirring section 51 Driving section 52 Blade section 60 Flow path setting section 80 Plate 90 Press roll 100 Second press roll device 100a, 100b Second press roll DR1 Conveying direction DR2 Width direction DR3 Vertical direction P Powder

Claims

1. A manufacturing apparatus for an electrode, comprising: a supply unit configured to supply powder to a sheet-like base material; an opposing unit extending in the width direction of the base material, substantially orthogonal to the conveyance direction in which the base material is conveyed, and configured to press the powder supplied by the supply unit against the base material; a guide unit disposed upstream of the opposing unit in the conveyance direction and configured to guide the powder supplied from the supply unit to the base material; and a flow path setting unit provided between the opposing unit and the guide unit and configured to set a flow path of the powder existing between the opposing unit and the guide unit.

2. The manufacturing apparatus for an electrode according to claim 1, wherein in a cross section orthogonal to the width direction, a first interval between the flow path setting unit and the opposing unit is larger than a second interval between the opposing unit and the base material.

3. The manufacturing apparatus for an electrode according to claim 1 or 2, wherein a storage unit for storing the powder supplied from the supply unit is formed between the guide unit and the flow path setting unit, and in the vertical direction, a height of an upper end edge of the flow path setting unit is higher than a height of an upper surface of the powder stored in the storage unit.

4. The manufacturing apparatus for an electrode according to claim 1 or 2, wherein in a cross section orthogonal to the width direction, a second interval between the opposing unit and the base material is smaller than a third interval between a lower end edge of the flow path setting unit in the vertical direction and the base material.

5. The manufacturing apparatus for an electrode according to claim 1 or 2, wherein a backflow path through which the powder supplied to the base material flows back is formed between the flow path setting unit and the opposing unit, and the manufacturing apparatus for an electrode further comprises a suction unit configured to suck the powder accumulated in the backflow path.

6. The manufacturing apparatus for an electrode according to claim 1 or 2, wherein the opposing unit has a cylindrical or columnar shape.

7. A battery having an electrode manufactured using the manufacturing apparatus for an electrode according to claim 1 or 2.

8. A supply unit that supplies powder to a substrate, an opposing part provided downstream of the supply unit in the moving direction of the substrate, with the lower end being separated from the substrate and the lower end contacting the powder on the substrate, and a flow path setting part provided between the opposing part and the supply unit, being lower than the opposing part, with the lower end being separated from the substrate and the lower end contacting the powder on the substrate. The upper end of the flow path setting part has a region where the height decreases as it approaches a reference point in the width direction of the substrate. An apparatus for manufacturing an electrode.

9. In the apparatus for manufacturing an electrode according to claim 8, the position of any reference point of the flow path setting part is located on the supply unit side in a top view.

10. In the apparatus for manufacturing an electrode according to claim 8 or 9, the upper end of the flow path setting part has an inclined surface that slopes downward in a direction opposite to the moving direction of the substrate in at least a part of the width direction of the substrate.

11. In the apparatus for manufacturing an electrode according to claim 8 or 9, the distance between the opposing part and the substrate is smaller than the distance between the lower edge of the flow path setting part and the substrate.

12. In the apparatus for manufacturing an electrode according to claim 8 or 9, the substrate is an electrode used in a secondary battery, and the powder contains the active material of the electrode.

13. A method for manufacturing an electrode, using the apparatus for manufacturing an electrode according to claim 12 to manufacture an electrode.

14. A battery having an electrode manufactured using the method for manufacturing an electrode according to claim 13.

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