Manufacturing method for electrode and manufacturing apparatus for electrode

Abstract

To provide a manufacturing method for an electrode for a secondary battery that can reduce manufacturing costs without using slurry, and a manufacturing apparatus for an electrode for a secondary battery.SOLUTION: A manufacturing method for an electrode for a secondary battery includes a step for preparing a current collector 11 having an adhesive layer 12 formed on its surface, a step for forming a mixture layer 14 containing an active material 17 and a binder 18 on the current collector, and a step for forming an active material layer 15 on the current collector by heating and pressing the mixture layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an electrode for a secondary battery and an apparatus for manufacturing an electrode for a secondary battery. [Background technology]

[0002] Electrodes constituting secondary batteries such as lithium-ion secondary batteries are generally produced by applying a slurry in which an active material, a binder, and a conductive additive are dispersed onto a current collector and drying the slurry (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-92622 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional electrode manufacturing methods using slurry require a drying process because a solvent is used. Furthermore, when manufacturing electrodes using the roll-to-roll method, the installation area for the slurry drying section is larger than the area where the slurry is applied. This results in increased energy consumption and higher manufacturing costs. Furthermore, environmentally hazardous solvent vapor recovery and regeneration processes are required, further increasing manufacturing costs.

[0005] The present invention has been made in consideration of the above points, and its main object is to provide a method for manufacturing a battery for a secondary battery, which can reduce manufacturing costs without using a slurry, and an apparatus for manufacturing a battery for a secondary battery. [Means for solving the problem]

[0006] The method for manufacturing an electrode for a secondary battery according to the present invention includes the steps of: preparing a current collector having an adhesive layer formed on its surface; forming a mixture layer containing an active material and a binder on the current collector; and hot-pressing the mixture layer to form an active material layer on the current collector.

[0007] The manufacturing apparatus for an electrode for a secondary battery according to the present invention includes a mixture layer forming section that forms a mixture layer containing an active material and a binder on a current collector having an adhesive layer formed on its surface, and a heat pressing section that heat-presses the mixture layer to form an active material layer on the current collector. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a method for manufacturing a battery for a secondary battery, which does not use a slurry and can reduce manufacturing costs, and an apparatus for manufacturing a battery for a secondary battery. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram schematically illustrating a configuration of a manufacturing apparatus used in a method for manufacturing an electrode for a secondary battery according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view schematically illustrating the structure of a powder particle. [Figure 3] 1 is a flowchart showing steps of a method for manufacturing an electrode for a secondary battery according to an embodiment of the present invention. [Figure 4] FIG. 3 is a cross-sectional view schematically showing a state in which a powder particle sheet is formed on a current collector by a molding process. [Figure 5] FIG. 3 is a cross-sectional view schematically showing a state in which an active material layer is formed on a current collector by a hot pressing process. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0011] The secondary battery in this embodiment includes a lithium-ion secondary battery, a lithium-sulfur secondary battery, etc. The electrode has a structure in which an active material layer is formed on a current collector, and includes a positive electrode and a negative electrode. The active material layer includes an active material and a binder, and may further include a conductive additive.

[0012] Known materials can be used for the current collector, active material, binder, and conductive additive. For example, in the case of a lithium-ion battery, aluminum foil or the like is used for the positive electrode current collector, and copper foil is used for the negative electrode current collector. Furthermore, lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium iron phosphate (LiFePO4), or the like is used for the positive electrode active material, and graphite, silicon, lithium metal, or the like is used for the negative electrode active material. Polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), or the like is used for the binder. Carbon materials such as carbon black and acetylene black are used for the conductive additive.

[0013] 1 is a diagram schematically illustrating the configuration of a manufacturing apparatus 10 used in a method for manufacturing an electrode for a secondary battery according to an embodiment of the present invention. In this embodiment, a roll-to-roll manufacturing apparatus is described as an example in which an active material layer is formed on a current collector while the current collector is being transported, but a sheet-by-sheet manufacturing apparatus in which an active material layer is formed on each current collector may also be used.

[0014] As shown in FIG. 1, a manufacturing apparatus 10 for an electrode for a secondary battery in this embodiment includes a conveying section 20, an adhesive layer forming section 30, a mixture layer forming section 40, and a heat pressing section .

[0015] The conveying section 20 conveys the current collector 11. Specifically, the current collector 11 wound around the delivery roll 21 is pulled out and conveyed along a predetermined conveying path, and then the electrode 16 formed on the current collector 11 is wound around the take-up roll 22.

[0016] The adhesive layer forming unit 30 is disposed downstream of the delivery roll 21 and forms an adhesive layer 12 on the surface of the current collector 11. The adhesive layer forming unit 30 is composed of, for example, an application unit 31 and a drying unit 36. The application unit 31 includes a manifold 32 that stores a coating liquid in which an adhesive is dissolved in a solvent, and a slit 34 connected to the manifold 32. The coating liquid is supplied to the manifold 32 from a tank 33 that stores the coating liquid via a supply path 35. The coating liquid stored in the manifold 32 passes through the slit 34 and is applied to the surface of the current collector 11 from the outlet of the slit 34. The coating film applied to the surface of the current collector 11 is dried in the drying unit 36, and an adhesive layer 12 is formed on the surface of the current collector 11. The adhesive layer forming unit 30 may be a sheet-fed apparatus separate from the roll-to-roll manufacturing apparatus.

[0017] The mixture layer forming unit 40 is disposed downstream of the adhesive layer forming unit 30, and forms a mixture layer containing an active material and a binder on the current collector 11 having the adhesive layer 12 formed on the surface thereof. In this embodiment, the mixture layer forming unit 40 is composed of a supplying unit 50 that supplies powder particles 13 (see FIG. 2 ) having active material particles 17 coated on the surface thereof with binder 18 onto the current collector 11, and a forming unit 60 that forms the powder particles supplied onto the current collector 11 into a sheet shape.

[0018] The supply unit 50 is configured, for example, by a hopper, and supplies the powder particles 13 stored in the supply unit 50 onto the current collector 11 being conveyed.

[0019] 2 is a cross-sectional view schematically showing the structure of powder particle 13, and powder particle 13 has a structure in which a binder 18 and a conductive additive 19 are dispersed and coated on the surface of active material particle 17. A method for producing powder particle 13 will be described later.

[0020] The forming unit 60 is disposed downstream of the supply unit 50, and forms the mixture layer 14 by forming the powder particles 13 supplied to the current collector 11 into a sheet shape. The forming unit 60 is configured, for example, by a squeegee, and adjusts the thickness of the mixture layer 14 by adjusting the gap between the squeegee and the transported current collector 11. The forming unit 60 may also be configured by a mechanism that involves compression, such as a pressure roll.

[0021] The heat press unit 70 is disposed downstream of the molding unit 60 and heat presses the mixture layer 14 to form an active material layer 15 on the current collector 11. This forms an electrode 16 in which the active material layer 15 is formed on the current collector 11. In this embodiment, the heat press unit 70 is composed of a planar heating unit 80 that heats the mixture layer 14 in a non-contact manner, and a heat roll press unit 90 that is disposed downstream of the planar heating unit 80. The planar heating unit 80 is composed of, for example, an infrared lamp, and the heat roll press unit 90 is composed of, for example, a pair of heat rolls. The planar heating unit 80 may be omitted.

[0022] The electrode 16 formed in the hot press section 70 is taken up by a take-up roll 22 disposed downstream of the hot press section 70 .

[0023] Next, a method for manufacturing an electrode for a secondary battery according to this embodiment will be described.

[0024] FIG. 3 is a flowchart showing a method for manufacturing an electrode for a secondary battery according to this embodiment.

[0025] As shown in FIG. 3, first, a current collector 11 having an adhesive layer 12 formed on its surface is prepared (step S1). Such current collector 11 can be formed, for example, by applying a coating liquid prepared by dissolving the material (adhesive) of adhesive layer 12 in a solvent to the surface of current collector 11 and drying the coating liquid. Here, the adhesive can be the same material as binder 18 coated on the surfaces of active material particles 17 of powder particles 13. Furthermore, adhesive layer 12 may contain the same material as conductive additive 19 coated on the surfaces of active material particles 17. Furthermore, the adhesive can be the same material as the binder contained in the active material layer of a battery or a material having lithium ion conductivity, such as a polymer electrolyte.

[0026] Next, powder particles 13 in which the surfaces of active material particles 17 are coated with binder 18 as shown in Fig. 2 are supplied onto current collector 11 (supplying step: step S2). Note that if the surfaces of powder particles 13 are not coated with conductive additive 19, a mixture of powder particles 13 and conductive additive 19 may be supplied onto current collector 11.

[0027] The powder particles 13 can be produced, for example, by dispersing the active material particles 17 in a solvent in which the binder 18 and the conductive additive 19 are dissolved, and then evaporating the solvent. Alternatively, the powder particles 13 may be produced by mixing and heating the active material particles 17 with the binder 18 and the conductive additive 19, each having a particle size smaller than that of the active material particles 17.

[0028] Next, the powder particles 13 supplied onto the current collector 11 are formed into a sheet (forming step: step S3). As a result, a mixture layer 14 is formed on the current collector 11. The forming step is preferably performed by rolling the powder particles 13 supplied onto the current collector 11 for reasons that will be described later.

[0029] 4 is a cross-sectional view schematically showing a state in which a mixture layer 14 is formed on a current collector 11 by a molding process. In this state, the powder particles 13 are simply dispersed in a sheet-like form at a constant density, and there are few locations where the active material particles 17 contact each other or where the active material particles 17 contact the adhesive layer 12 formed on the surface of the current collector 11 via the binder 18. As a result, the contact resistance between the active material particles 17 is large, and the binding strength between the active material particles 17 and the adhesive layer 12 is also weak.

[0030] Next, the mixture layer 14 formed on the current collector 11 is hot-pressed (hot-pressing step: step S4).

[0031] FIG. 5 is a cross-sectional view schematically illustrating the state in which an active material layer 15 is formed on a current collector 11 by a hot pressing process. In this state, the binder 18 coated on the surfaces of the active material particles 17 is softened by heating, and the active material particles 17 are compressed by the pressing of the mixture layer 14, thereby increasing the contact area between the active material particles 17. This reduces the contact resistance between the active material particles 17. In addition, the adhesive layer 12 formed on the current collector 11 is softened by heating, and the active material particles 17 compressed by the pressing of the mixture layer 14 sink into the softened adhesive layer 12, thereby increasing the contact area between the active material particles 17 and the adhesive layer 12. This increases the binding strength between the active material particles 17 and the adhesive layer 12, thereby reducing the contact resistance between the active material particles 17 and the current collector 11.

[0032] As described above, the mixture layer 14 is preferably formed by rolling the powder particles 13 supplied onto the current collector 11. The binder 18, such as PVDF, coated on the surfaces of the active material particles 17 has good slip properties, so that the density of the powder particles 13 can be improved by rolling the powder particles 13 supplied onto the current collector 11. This improves the thermal conductivity in the heat-pressing step of the mixture layer 14, and therefore the binder 18 can be melted more quickly.

[0033] The electrode manufacturing method of this embodiment does not use a solvent, unlike conventional electrode manufacturing methods that use a slurry, and therefore does not require a step of drying the slurry or a step of recovering and regenerating the solvent vapor, thereby significantly reducing the electrode manufacturing cost.

[0034] Furthermore, in the manufacturing method of the electrode according to the present embodiment, in the molding step (step S3), the mixture layer 14 formed on the current collector 11 has the powder particles 13 uniformly dispersed in a state in which the surfaces of the active material particles 17 are coated with the binder 18, and therefore the binder 18 is also uniformly dispersed. Therefore, in the subsequent hot pressing step (step S4), the active material particles 17 can be uniformly bound together and between the active material particles 17 and the adhesive layer 12 by the molten binder 18. As a result, a secondary battery with excellent cycle characteristics can be realized.

[0035] Furthermore, in the electrode manufacturing method of this embodiment, by forming adhesive layer 12 in advance on the surface of current collector 11, in the hot pressing step (step S4), active material particles 17 compressed by pressing sink into adhesive layer 12 softened by heating, increasing the contact area between active material particles 17 and adhesive layer 12, thereby increasing the bonding strength between active material particles 17 and adhesive layer 12. Note that because adhesive layer 12 is in contact with current collector 11 over the entire surface, the bonding strength between the adhesive layer and the current collector is significantly greater than the bonding strength between the adhesive layer and the active material layer. Therefore, the bonding strength between the active material layer and the current collector is also increased. [Example]

[0036] The present invention will be explained in more detail below by way of examples, but the present invention is not limited to these examples in any way.

[0037] Example 1 <Preparation of positive electrode current collector> A coating solution prepared by dissolving 10 wt% of an adhesive (PVDF) in a solvent (NMP: N-methyl-pyrrolidone) was applied to the surface of a 20 μm-thick current collector (aluminum foil) 11, and then dried at a temperature of 120°C for 10 hours to produce a current collector with a 5 μm-thick adhesive layer 12 formed on the surface.

[0038] <Preparation of powder particles for the positive electrode> 0.45 g of active material particles (LFP: lithium iron phosphate) 17 were dissolved in a solvent (N-methyl-pyrrolidone: NMP) with 5 wt % of binder (PVDF) 18 and 5 wt % of conductive additive (carbon black: CB) 19. 0.45 g of the active material particles 17 were dispersed in the solvent, and the solvent was then heated to evaporate. This produced powder particles 13 in which the surfaces of the active material particles 17 were coated with the binder 18 and conductive additive 19.

[0039] <Preparation of positive electrode> Powder particles 13 prepared by the above method were supplied onto current collector (aluminum foil) 11 having a thickness of 20 μm, which was also prepared by the above method, and then powder particles 13 supplied onto current collector 11 were formed into a sheet having a thickness of 100 μm, thereby forming a mixture layer 14 on current collector 11. Thereafter, mixture layer 14 was pressed and held at room temperature and a pressure of 50 kN for 15 seconds, and then hot-pressed and held at a temperature of 200° C. and a pressure of 50 kN for 15 seconds, thereby producing a positive electrode 16 in which an active material layer 15 was formed on current collector 11.

[0040] Example 2 A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 1, except that the concentration of binder (PVDF) 18 relative to active material particles (LFP: lithium iron phosphate) 17 was set to 3 wt %.

[0041] Example 3 A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 1, except that the concentration of binder (PVDF) 18 relative to active material particles (LFP: lithium iron phosphate) 17 was set to 2 wt %.

[0042] Example 4 A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 1, except that the concentration of binder (PVDF) 18 relative to active material particles (LFP: lithium iron phosphate) 17 was set to 1 wt %.

[0043] Example 5 A positive electrode 16 in which an active material layer 15 was formed on a current collector 11 was produced under the same conditions as in Example 1, except that the material of the adhesive layer 12 was a polymer electrolyte. The thickness of the adhesive layer 12 was 10 μm.

[0044] Example 6 A positive electrode 16 in which an active material layer 15 was formed on a current collector 11 was produced under the same conditions as in Example 2, except that the material of the adhesive layer 12 was a polymer electrolyte.

[0045] Example 7 A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 3, except that the material of the adhesive layer 12 was a polymer electrolyte.

[0046] Example 8 A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 4, except that the material of the adhesive layer 12 was a polymer electrolyte.

[0047] (Comparative Example 1) A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 1, except that a current collector 11 on the surface of which no adhesive layer 12 was formed was used.

[0048] (Comparative Example 2) A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 2, except that a current collector 11 on the surface of which no adhesive layer 12 was formed was used.

[0049] (Comparative Example 3) A positive electrode 16 having an active material layer 15 formed on a current collector 11 was produced under the same conditions as in Example 4, except that a current collector 11 on the surface of which no adhesive layer 12 was formed was used.

[0050] Comparative Example 4 Using a conventional method, 0.45 g of active material particles (LFP), 5 wt % of a binder (PVDF) relative to the active material particles, and 5 wt % of a conductive additive (CB) relative to the active material particles were mixed in an organic solvent (NMP) to form a slurry.This slurry was then applied to a current collector (aluminum foil) on whose surface no adhesive layer 12 was formed, and then heated and pressed at a temperature of 200°C and a pressure of 50 kN for 15 seconds to produce a positive electrode in which an active material layer was formed on a current collector 11.

[0051] <Fabrication of lithium-ion secondary batteries> The positive electrode 16 produced in Examples 1 to 8 and Comparative Examples 1 to 4 above and a negative electrode using lithium metal as an active material were wound with a separator interposed therebetween to produce an electrode body, and this electrode body was housed in a battery case together with a non-aqueous electrolyte to produce a lithium ion secondary battery.

[0052] For each of the lithium ion secondary batteries fabricated by the above method, the battery capacity and the binding strength between the active material layer of the positive electrode and the current collector were measured by the following methods.

[0053] <Battery capacity measurement> The fabricated lithium-ion secondary battery was charged at a constant current, and the total current (mAh) was measured until the set voltage (4.3 V) was reached. The battery capacity (charge) was calculated (mAh / g) from the battery mass measured beforehand. After waiting for 10 seconds, the battery was discharged at a constant current, and the total current (mAh) was measured until the set voltage (2.8 V) was reached. The battery capacity (discharge) was calculated (mAh / g) from the battery mass measured beforehand. This charge / discharge cycle was repeated three times, and the battery capacity (discharge) calculated after the third cycle was determined as the battery capacity. The current value in each measurement was a value corresponding to the weight of the active material in the electrode, specifically, (theoretical capacity of the active material) × (weight of the active material in the electrode) × 1 / 20.

[0054] <Measurement of the adhesive strength between the positive electrode active material layer and the current collector> The mass A of the current collector was measured in advance, and a positive electrode having an active material layer formed on the current collector was fabricated by the methods of Examples 1 to 8 and Comparative Examples 1 to 4 above, and the mass B of the fabricated positive electrode was measured. Next, the active material layer was held facing downward relative to the current collector, and the mass C of the positive electrode was measured when the active material layer no longer fell off. Then, the adhesion ratio between the active material layer and the current collector was calculated using the following formula, and this adhesion ratio was used as an index for evaluating the binding strength between the active material layer of the positive electrode and the current collector.

[0055] In the case of current collector 11 having adhesive layer 12 formed on the surface thereof (Examples 1 to 4), adhesive layer 12 is in contact with current collector 11 over the entire surface, and therefore the binding strength between adhesive layer 12 and current collector 11 is sufficiently greater than the binding strength between adhesive layer 12 and active material layer 15. Therefore, in the lithium ion secondary batteries fabricated using the positive electrodes fabricated in Examples 1 to 8, the binding strength measured by the above method can be considered to be the binding strength between current collector 11 and active material layer 15 of the positive electrode.

[0056] Adhesion ratio = (CA) / (BA) Table 1 shows the results of measuring the battery capacity of each of the lithium ion secondary batteries produced and the adhesion ratio between the positive electrode active material and the current collector.

[0057] [Table 1]

[0058] As shown in Table 1, it was confirmed that the lithium ion secondary batteries fabricated using the positive electrodes fabricated by the methods of Examples 1 to 4 had performance equivalent to that of the lithium ion secondary battery fabricated using the positive electrode fabricated using the conventional slurry (Comparative Example 4) in terms of battery capacity and the binding strength (adhesion ratio) between the active material layer 15 and the current collector 11.

[0059] As described above, the electrode manufacturing method of this embodiment does not use a solvent, unlike conventional electrode manufacturing methods that use a slurry, and therefore does not require the steps of drying the slurry or the steps of recovering and regenerating the solvent vapor, thereby significantly reducing the electrode manufacturing cost.

[0060] Furthermore, as shown in Examples 1 to 4, even when the concentration of binder (PVDF) 18 relative to active material particles (LFP) 17 is reduced to 1 wt%, the binding strength between the active material layer 15 and the current collector 11 does not decrease, whereas as shown in Comparative Examples 1 to 3, when the concentration of binder (PVDF) 18 relative to active material particles (LFP) 17 is reduced to 3 wt% or less, the binding strength between the active material layer 15 and the current collector 11 decreases.

[0061] This is because in Comparative Examples 1 to 3, adhesive layer 12 is not formed on current collector 11, and therefore in the hot pressing step (step S4), the active material particles 17 compressed by pressing do not sink into adhesive layer 12 softened by heating. Therefore, the contact area between active material particles 17 and current collector 11 is reduced by the amount of the reduced concentration of binder 18, and as a result, it is thought that the binding strength between active material particles 17 and adhesive layer 12 is reduced.

[0062] As described above, in the method for manufacturing an electrode according to this embodiment, when PVDF is used as the material for the adhesive layer 12, the concentration of the binder (PVDF) 18 relative to the active material particles (LFP) 17 can be reduced from 5 wt % to 1 wt %, compared to when no adhesive layer 12 is formed on the current collector 11. This reduces the amount of binder 18 that does not contribute to the battery capacity, thereby improving the rate characteristics of the battery.

[0063] Furthermore, as shown in Examples 5 and 6, even when a polymer electrolyte was used as the material for the adhesive layer 12, it was confirmed that the battery capacity and the binding strength (adhesion ratio) between the active material layer 15 and the current collector 11 had performance equivalent to that of a lithium ion secondary battery fabricated using a positive electrode fabricated using a conventional slurry (Comparative Example 4).

[0064] On the other hand, as shown in Examples 7 and 8, when the concentration of the binder (PVDF) 18 relative to the active material particles (LFP) 17 was reduced to 2 wt% or less, the binding strength (adhesion ratio) between the active material layer 15 and the current collector 11 was not sufficient, and the battery capacity could not be measured.

[0065] In this way, when a polymer electrolyte is used as the material for the adhesive layer 12, the concentration of the binder (PVDF) 18 relative to the active material particles (LFP) 17 can be reduced from 5 wt % to 3 wt % compared to when no adhesive layer 12 is formed on the current collector 11. This allows the amount of binder 18 that does not contribute to the battery capacity to be reduced, thereby improving the rate characteristics of the battery.

[0066] While the present invention has been described above with reference to preferred embodiments, these descriptions are not limiting and various modifications are possible. For example, in the above embodiment, powder particles 13, in which the surfaces of active material particles 17 are coated with binder 18, are supplied onto current collector 11, and then powder particles 13 are formed into a sheet to form mixture layer 14 containing the active material and binder. However, mixture layer 14 containing the active material and binder may also be formed by applying a slurry containing the active material and binder onto current collector 11 and drying it. [Explanation of symbols]

[0067] 10. Electrode manufacturing equipment 11 Current collector 12 Adhesive layer 13 Powder particles 14 Mixture layer 15 Active material layer 16 Electrode (positive electrode) 17 Active material particles 18 Binder 19 Conductive additives 20 Conveying section 21 Delivery roll 22 Take-up roll 30 Adhesive layer forming part 31 Application section 32 Manifold 33 Tank 34 Slit 35 Supply route 36 Drying section 40 Mixture layer forming section 50 Supply section 60 Molding section 70 Heat Press Section 80 Planar heating section 90 Heating roll press section

Claims

1. A method for manufacturing an electrode for a secondary battery, comprising: A step (A) of preparing a current collector having an adhesive layer formed on its surface; (B) forming a mixture layer containing an active material and a binder on the current collector; a step (C) of hot-pressing the mixture layer to form an active material layer on the current collector; A method for manufacturing an electrode, comprising:

2. In the step (B), the mixture layer has a configuration in which powder particles in which the surfaces of active material particles are coated with a binder are formed into a sheet shape, The step (B) a supplying step of supplying powder particles, in which the surfaces of active material particles are coated with a binder, onto the current collector; a forming step of forming the powder particles supplied onto the current collector into a sheet shape; The method for manufacturing the electrode of claim 1 , comprising:

3. The method for manufacturing an electrode according to claim 2 , wherein in the supplying step, the powder particles further comprise active material particles whose surfaces are coated with a conductive additive.

4. The method for manufacturing an electrode according to claim 2 , wherein the supplying step is performed by supplying a mixture of the powder particles and the conductive additive onto the current collector.

5. The method for producing an electrode according to claim 1 , wherein the steps (B) and (C) are carried out continuously while the current collector prepared in the step (A) is being transported.

6. 3. The method for manufacturing an electrode according to claim 2, wherein in the supplying step, the powder particles are obtained by dispersing the active material particles in a solvent in which the binder is dissolved, and then evaporating the solvent.

7. The method for manufacturing an electrode according to claim 1 , wherein the adhesive layer and the binder are made of the same material.

8. An apparatus for manufacturing electrodes for secondary batteries, comprising: a mixture layer forming section that forms a mixture layer containing an active material and a binder on a current collector having an adhesive layer formed on its surface; a heat press unit that heat-presses the mixture layer to form an active material layer on the current collector; An electrode manufacturing apparatus comprising:

9. The electrode manufacturing apparatus according to claim 8 , further comprising an adhesive layer forming section that forms the adhesive layer on the surface of the current collector.

10. The mixture layer forming section is a supply unit that supplies powder particles, in which the surfaces of active material particles are coated with a binder, onto the current collector; a forming unit that forms the powder particles supplied onto the current collector into a sheet shape; The electrode manufacturing apparatus according to claim 8 , comprising:

11. The electrode manufacturing apparatus according to claim 10 , wherein the powder particles further include a conductive additive coated on the surfaces of the active material particles.

12. The electrode manufacturing apparatus according to claim 10 , wherein the supply unit supplies the mixture of the powder particles and the conductive additive particles onto the current collector.

13. a conveying unit that conveys the current collector having an adhesive layer formed on its surface, The electrode manufacturing apparatus according to claim 8 , wherein the heat press unit is disposed downstream of the mixture layer forming unit in a transport direction of the current collector transported by the transport unit.

14. 11. The electrode manufacturing apparatus according to claim 10, wherein the powder particles are obtained by dispersing the active material particles in a solvent in which the binder is dissolved, and then evaporating the solvent.

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