Manufacturing method of electrode for lithium ion batteries and manufacturing device

Abstract

To provide a manufacturing method of an electrode for lithium ion batteries capable of suppressing a residual electrode active material composition on a top face of a sealing material, and a manufacturing device.SOLUTION: A belt-like mask material 8 having an opening 8a of a size smaller than an opening 108a of a belt-like sealing material 108L is laminated on a top face of the belt-like sealing material 108, and an inner peripheral edge 8c of the opening 8a of the belt-like mask material 8 is folded into the opening 108a of the belt-like sealing material 108L. A cathode active material composition 9 is supplied into the opening 108a of the belt-like sealing material 108L, the cathode active material composition 9 is compressed by a pressurizing / mask material removing roller 7a, etc., thereby forming a cathode active material layer, and the belt-like mask material 8 is removed from the top face of the belt-like sealing material 108L.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and an apparatus for producing an electrode for a lithium ion battery. [Background technology]

[0002] Lithium ion batteries have advantages such as being small and lightweight, having a high energy density, and having a small self-discharge rate, and are therefore widely used as storage batteries for automobiles, storage batteries for electrical and electronic devices, etc. Patent Document 1 discloses a method for producing such a lithium ion battery in which a positive electrode having a positive electrode active material layer formed on a positive electrode current collector and a negative electrode having a negative electrode active material layer formed on a negative electrode current collector are laminated with a separator interposed therebetween, and the outer peripheries of the positive electrode active material layer and the negative electrode active material layer are sealed with a sealant.

[0003] The manufacturing method of the lithium-ion battery described in Patent Document 1 includes an electrode manufacturing process for manufacturing positive electrodes and negative electrodes with sealing material disposed on the outer periphery, and an assembly process for stacking the positive electrodes and negative electrodes manufactured in the electrode manufacturing process with a separator and bonding the sealing materials of the positive electrodes and negative electrodes together.

[0004] The electrode manufacturing process includes a supplying step, a compressing step, and a recovering step. In the supplying step, a frame-shaped sealant, an electrode current collector that covers the bottom surface of the sealant, and a frame-shaped masking material that covers the top surface of the sealant are prepared, and an electrode active material composition containing electrode active material particles is supplied to the space surrounded by the sealant and the electrode current collector. In the compressing step, the electrode active material composition is compressed to form an electrode active material layer of uniform thickness. In the recovering step, the masking material is peeled off from the top surface of the sealant to recover the masking material and the electrode active material composition that has spilled onto the masking material. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-044152 Summary of the Invention [Problem to be solved by the invention]

[0006] In the electrode manufacturing process described in Patent Document 1, the upper surface of the sealing material is covered with a mask material to prevent the electrode active material composition from remaining on the upper surface of the sealing material. If the electrode active material composition remains on the upper surface of the sealing material, it will affect the sealing property when the sealing materials are bonded to each other in the next combining process. However, even when the upper surface of the sealing material is covered with a mask material, the electrode active material composition sometimes remains on the sealing material. This is thought to be due to misalignment of the mask material with respect to the sealing material or excessive supply of the electrode active material composition to the sealing material.

[0007] Therefore, an object of the present invention is to provide a method and an apparatus for manufacturing an electrode for a lithium ion battery that can suppress the residue of an electrode active material composition on the upper surface of a sealing material. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the present invention provides a method for manufacturing an electrode for a lithium-ion battery, comprising: a sealing material having an opening; an electrode current collector laminated on the lower surface of the sealing material to close the opening; and an electrode active material layer provided in the opening, the method comprising the steps of: laminating a mask material having an opening slightly smaller than the opening of the sealing material on the upper surface of the sealing material and folding the inner edge of the opening of the mask material into the opening of the sealing material; a supplying step of supplying an electrode active material composition containing electrode active material particles into the opening of the sealing material; a compressing step of compressing the electrode active material composition to form the electrode active material layer; and a mask removing step of removing the mask material from the upper surface of the sealing material. Effect of the Invention

[0009] According to the present invention, it is possible to provide a manufacturing method and a manufacturing method for an electrode for a lithium ion battery that are capable of suppressing the electrode active material composition from remaining on the upper surface of a sealing material. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing a configuration of a manufacturing apparatus for a lithium ion battery electrode according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view showing a configuration of a lithium-ion battery according to an embodiment of the present invention. [Diagram 3] 3A to 3C are cross-sectional views showing an assembly process for producing the lithium ion battery shown in FIG. 2. [Figure 4] 2 is a cross-sectional view showing a state in which a strip-shaped positive electrode current collector is laminated under a strip-shaped sealing material in the manufacturing apparatus shown in FIG. 1. [Diagram 5] 2A and 2B are a cross-sectional view and a plan view showing a state in which a strip-shaped mask material is laminated on a strip-shaped sealing material in the manufacturing apparatus shown in FIG. [Figure 6] 2A and 2B are a cross-sectional view and a plan view showing a state in which the inner peripheral edge of the opening of the belt-shaped masking material is folded into the opening of the belt-shaped sealing material in the manufacturing apparatus shown in FIG. [Figure 7] 2 is a cross-sectional view showing a state in which a positive electrode active material composition is supplied into an opening of a strip-shaped sealing material while the amount of the composition stored in a hopper is being measured in the manufacturing apparatus shown in FIG. 1. FIG. [Figure 8] 2 is a cross-sectional view showing a state in which the belt-shaped mask material is removed while compressing the positive electrode active material composition in the openings of the belt-shaped sealing material in the manufacturing apparatus shown in FIG. 1. FIG. [Figure 9] 3 is a flowchart showing the steps of a method for manufacturing a lithium ion battery electrode according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the embodiments shown in the drawings. Note that the lithium ion battery in this specification includes a lithium ion secondary battery.

[0012] 1 to 9 show an embodiment of the present invention, and Fig. 1 is a perspective view showing a schematic configuration of a manufacturing apparatus for a lithium ion battery electrode (hereinafter referred to as "electrode manufacturing apparatus 1") according to the embodiment of the present invention. The electrode manufacturing apparatus 1 is an apparatus for manufacturing lithium ion battery electrodes (positive electrode 101A and negative electrode 101B) constituting a lithium ion battery 101 during the manufacturing process of the lithium ion battery 101.

[0013] 2, the lithium ion battery 101 is formed by stacking a positive electrode 101A in which a positive electrode active material layer 103 is formed on the surface of a resin positive electrode collector 102 and a negative electrode 101B in which a negative electrode active material layer 105 is formed on the surface of a resin negative electrode collector 104, with a separator 106 interposed between them, so that the positive electrode active material layer 103 and the negative electrode active material layer 105 face each other. The periphery of the positive electrode collector 102 and the negative electrode collector 104 are sealed with a sealant 107 so that the positive electrode collector 102 and the negative electrode collector 104 are arranged and held at a predetermined interval. As a result, the lithium ion battery 101 is formed into a substantially rectangular flat plate shape as a whole.

[0014] 3, the manufacturing process of the lithium ion battery 101 includes an electrode manufacturing process for manufacturing a positive electrode 101A having a sealant 108 disposed around a positive electrode active material layer 103 and a negative electrode 101B having a sealant 109 disposed around a negative electrode active material layer 105, and a combination process for laminating the positive electrode 101A and the negative electrode 101B manufactured in the electrode manufacturing process with a separator 106 and bonding the sealant 108 and the sealant 109. The sealant 108 and the sealant 109 function as a sealant 107 that seals the inside of the lithium battery 101 by being bonded.

[0015] 1 shows an electrode manufacturing apparatus 1 for manufacturing a positive electrode 101A, which is provided in a manufacturing line for a lithium ion battery 101. Although not shown in detail, an electrode manufacturing apparatus for a negative electrode 101B is also provided in the manufacturing line for the lithium ion battery 101, in addition to the electrode manufacturing apparatus 1 for the positive electrode 101A. Note that the electrode manufacturing apparatus for the negative electrode 101B has a similar configuration to the electrode manufacturing apparatus 1 for the positive electrode 101A, and therefore a detailed description thereof will be omitted.

[0016] The electrode manufacturing apparatus 1 includes a conveying roller 2, a current collector laminating roller 3, a mask material laminating roller 4, a mask material folding section 5, a positive electrode active material composition supplying section 6, a pressure / mask material removing roller 7a, and a pressure receiving roller 7b. The conveying roller 2 intermittently conveys a long strip-shaped sealing material 108L, a long strip-shaped positive electrode current collector 102L laminated under the strip-shaped sealing material 108L, and a long strip-shaped mask material 8 laminated on the strip-shaped sealing material 108L in the direction of arrow A. Although not shown in detail, a cutting section is provided on the most downstream side in the direction of arrow A for cutting the strip-shaped sealing material 108L and the strip-shaped positive electrode current collector 102L to form a plurality of positive electrodes 101A.

[0017] The strip-shaped sealing material 108L is made of a strip-shaped plastic film having a plurality of openings 108a at predetermined intervals in which the positive electrode active material layer 103 is formed. The strip-shaped sealing material 108L is intermittently conveyed by conveying rollers 2 in the direction of arrow A at intervals where the openings 108a are provided. The strip-shaped sealing material 108L is cut between the openings 108a during periods when the intermittent conveyance is stopped, thereby forming the sealing material 108 constituting the positive electrode 101A of the lithium ion battery 101.

[0018] The material of the strip-shaped sealing material 108L is not particularly limited as long as it is a material that is durable against the electrolyte, but a polymer material is preferable, and a thermosetting polymer material is more preferable. Examples of the thermosetting polymer material include epoxy resin, polyolefin resin, polyurethane resin, and polyvinylidene fluoride resin, and epoxy resin is preferable because it is durable and easy to handle. In addition, as the strip-shaped sealing material 108L, a double-sided tape-like sealing material (such as a sealing material formed by applying the above-mentioned thermosetting polymer material to both sides of a flat base material) can be suitably used, and for example, a known sealing film with a three-layer structure (such as a film in which a modified polypropylene film is laminated on the top and bottom of a polyethylene naphthalate film) can be used.

[0019] The width and thickness of the strip-shaped sealing material 108L, the size of the opening 108a, and the like are not particularly limited and may be appropriately set according to the lithium ion battery 101 to be manufactured. When the lithium ion battery 101 to be manufactured is rectangular, the width of the strip-shaped sealing material 108L is preferably 30 to 2000 mm, and more preferably 40 to 1000 mm, per side. From the viewpoint of providing sufficient strength to the sealing material 108 after cutting, the thickness of the strip-shaped sealing material 108L is preferably 5 to 20 mm, and more preferably 10 to 20 mm, for example.

[0020] A method for providing the multiple openings 108a in the strip-shaped sealing material 108L includes a punching process in which a predetermined punching process is performed while intermittently conveying the strip-shaped sealing material 108L. The punching process may be performed continuously with the electrode manufacturing process, or the strip-shaped sealing material 108L in which the openings 108a have been punched in a separate process may be supplied to the electrode manufacturing process.

[0021] The shape of the sealing material 108 of the lithium ion battery 101 is not particularly limited, and examples thereof include polygons such as triangles, rectangles, and pentagons, circles, and ellipses. However, when the sealing material 108 is continuously formed using the strip-shaped sealing material 108L, a rectangle is preferable.

[0022] The strip-shaped positive electrode current collector 102L is made of, for example, a long plastic film. The strip-shaped positive electrode current collector 102L is guided by a current collector lamination roller 3 and laminated under the strip-shaped sealing material 108L. As a result, as shown in the cross-sectional view of FIG. 4, the bottom surface of each opening 108a of the strip-shaped sealing material 108L is blocked by the strip-shaped positive electrode current collector 102L. The strip-shaped positive electrode current collector 102L is intermittently conveyed together with the strip-shaped sealing material 108L in the direction of arrow A by the conveying roller 2. The strip-shaped positive electrode current collector 102L is cut together with the strip-shaped sealing material 108L to form the positive electrode current collector 102 constituting the positive electrode 101A of the lithium ion battery 101.

[0023] The strip-shaped positive electrode current collector 102L may be a current collector used in a known lithium ion battery, such as a known metal current collector or a resin current collector made of a conductive material and a synthetic resin (such as the resin current collectors described in JP 2012-150905 A and WO 2015-005116 A). From the viewpoint of battery characteristics, the strip-shaped positive electrode current collector 102L is preferably a resin current collector.

[0024] Examples of the metal current collector include one or more metal materials selected from the group consisting of copper, aluminum, titanium, nickel, tantalum, niobium, hafnium, zirconium, zinc, tungsten, bismuth, antimony, alloys containing one or more of these metals, and stainless steel alloys. These metal materials may be used in the form of a thin plate or metal foil. In addition, the above metal materials may be formed on the surface of a substrate made of a material other than the above metal materials by a method such as sputtering, electrodeposition, or coating, and used as the metal current collector.

[0025] The resin collector preferably contains a conductive filler and a matrix resin. Examples of the matrix resin include polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), polycycloolefin (PCO), polyethylene terephthalate (PET), polyethernitrile (PEN), polytetrafluoroethylene (PTFE), styrene-butadiene rubber (SBR), polyacrylonitrile (PAN), polymethylacrylate (PMA), polymethylmethacrylate (PMMA), polyvinylidene fluoride (PVdF), epoxy resin, silicone resin, or a mixture thereof. From the viewpoint of electrical stability, polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), and polycycloolefin (PCO) are preferred, and polyethylene (PE), polypropylene (PP), and polymethylpentene (PMP) are more preferred.

[0026] The conductive filler is selected from materials having electrical conductivity. Specific examples include metals [nickel, aluminum, stainless steel (SUS), silver, copper, titanium, etc.], carbon [graphite and carbon black (acetylene black, ketjen black, furnace black, channel black, thermal lamp black, etc.)], and mixtures thereof, but are not limited thereto. These conductive fillers may be used alone or in combination of two or more. In addition, alloys or metal oxides thereof may be used. From the viewpoint of electrical stability, aluminum, stainless steel, carbon, silver, copper, titanium, and mixtures thereof are preferable, silver, aluminum, stainless steel, and carbon are more preferable, and carbon is even more preferable. In addition, these conductive fillers may be those in which a conductive material (a metal among the above-mentioned conductive filler materials) is coated around a particulate ceramic material or a resin material by plating or the like.

[0027] The average particle diameter of the conductive filler is not particularly limited, but is preferably 0.01 to 10 μm, more preferably 0.02 to 5 μm, and even more preferably 0.03 to 1 μm, from the viewpoint of the electrical properties of the battery. In this specification, the term "particle diameter" refers to the maximum distance L between any two points on the contour line of a particle. The value of the "average particle diameter" is calculated as the average value of the particle diameters of particles observed in several to several tens of fields of view using an observation means such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM).

[0028] The shape (form) of the conductive filler is not limited to a particulate form, and may be a form other than a particulate form, and may be a form that has been put into practical use as a so-called filler-based conductive resin composition, such as carbon nanotubes.

[0029] The conductive filler may be a conductive fiber having a fibrous shape. Examples of the conductive fiber include carbon fibers such as PAN-based carbon fibers and pitch-based carbon fibers, conductive fibers obtained by uniformly dispersing metals or graphite having good conductivity in synthetic fibers, metal fibers obtained by fiberizing metals such as stainless steel, conductive fibers obtained by coating the surface of organic fibers with metal, and conductive fibers obtained by coating the surface of organic fibers with resin containing a conductive substance. Among these conductive fibers, carbon fibers are preferred. Polypropylene resin kneaded with graphene is also preferred. When the conductive filler is a conductive fiber, the average fiber diameter is preferably 0.1 to 20 μm.

[0030] The weight percentage of the conductive filler in the resin collector is preferably 5 to 90% by weight, and more preferably 20 to 80% by weight. In particular, when the conductive filler is carbon, the weight percentage of the conductive filler is preferably 20 to 30% by weight.

[0031] The resin current collector may contain other components (such as a dispersant, a crosslinking accelerator, a crosslinking agent, a colorant, an ultraviolet absorber, and a plasticizer) in addition to the matrix resin and the conductive filler. A plurality of resin current collectors may be laminated, or a resin current collector and a metal foil may be laminated.

[0032] The width of the strip-shaped positive electrode current collector 102L may be appropriately set depending on the lithium ion battery 101 to be manufactured, but is preferably approximately the same as the width of the strip-shaped sealing material 108L described above. The thickness of the strip-shaped positive electrode current collector 102L is not particularly limited, but is preferably 5 to 150 μm. When a plurality of resin current collectors are stacked to be used as a positive electrode current collector, the total thickness after stacking is preferably 5 to 150 μm.

[0033] The strip-shaped positive electrode collector 102L can be obtained, for example, by melt-kneading a matrix resin, a conductive filler, and a filler dispersant, if necessary, to form a conductive resin composition into a film by a known method. Examples of a method for forming a conductive resin composition into a film include known film forming methods such as a T-die method, an inflation method, and a calendar method. The strip-shaped positive electrode collector 102L can also be obtained by a forming method other than film forming.

[0034] Although the strip-shaped positive electrode current collector 102L has been described above, the electrode manufacturing apparatus for the negative electrode 101B also uses a strip-shaped negative electrode current collector. As the strip-shaped negative electrode current collector, one having the same configuration as that described for the strip-shaped positive electrode current collector can be appropriately selected and used, and can be obtained by the same method. From the viewpoint of battery characteristics, the strip-shaped negative electrode current collector is preferably a resin current collector. In addition, the width of the strip-shaped negative electrode current collector may be appropriately set according to the lithium ion battery to be manufactured, but is preferably approximately the same as the size of the strip-shaped sealing material 108L described above. Furthermore, the thickness of the strip-shaped negative electrode current collector is not particularly limited, but is preferably 5 to 150 μm.

[0035] The strip-shaped mask material 8 is a mask material that covers the upper surface of the strip-shaped sealing material 108L in order to prevent the positive electrode active material composition from remaining on the upper surface of the strip-shaped sealing material 108L when the positive electrode active material composition is supplied into the opening 108a of the strip-shaped sealing material 108L. The strip-shaped mask material 8 is made of, for example, a long plastic film or a long metal sheet, and is guided by a mask material lamination roller 4 to be laminated on the strip-shaped sealing material 108L.

[0036] The strip-shaped mask material 8 is provided with a plurality of openings 8a at the same predetermined intervals as the openings 108a of the strip-shaped sealing material 108L. That is, the strip-shaped mask material 8 is laminated on the strip-shaped sealing material 108L such that each opening 8a overlaps each opening 108a of the strip-shaped sealing material 108L, as shown in the cross-sectional view of FIG. 5(A).

[0037] The opening 8a of the strip-shaped mask material 8 is slightly smaller than the opening 108a of the strip-shaped sealing material 108L. Specifically, the opening 8a of the strip-shaped mask material 8 is smaller than the opening 108a of the strip-shaped sealing material 108L by the thickness T of the strip-shaped sealing material 108L. In addition, slits 8b are provided at each corner of the opening 8a of the strip-shaped mask material 8 in order to fold the inner periphery of the opening 8a of the strip-shaped mask material 8 into the opening 108a of the strip-shaped sealing material 108L. These slits 8b are provided so that their ends coincide with the corners of the opening 108a of the strip-shaped sealing material 108L, as shown in FIG. 5(B) showing the strip-shaped mask material 8 laminated on the strip-shaped sealing material 108L.

[0038] One method for providing the multiple openings 8a and slits 8b in the band-shaped mask material 8 is to perform a punching process in which a predetermined punching process is performed while intermittently conveying the band-shaped mask material 8. The punching process may be performed continuously with the electrode manufacturing process, or the band-shaped mask material 8 in which the openings 8a and slits 8b have been punched in a separate process may be supplied to the electrode manufacturing process.

[0039] The material of the strip-shaped mask material 8 is preferably a material that does not easily return to its original state (so-called spring back) when the inner periphery of the opening 8a is folded into the opening 108a of the strip-shaped sealing material 108L. The width of the strip-shaped mask material 8 is preferably the same as or wider than the strip-shaped sealing material 108L in order to prevent the positive electrode active material composition from remaining on the upper surface of the strip-shaped sealing material 108L. The thickness of the strip-shaped mask material 8 is not particularly limited, but is preferably as thin as possible because the strip-shaped mask material 8 is removed after the positive electrode active material composition is supplied into the opening 108a of the strip-shaped sealing material 108L, and is, for example, 50 μm to 600 μm, more preferably 150 μm to 450 μm.

[0040] The masking material folding unit 5 is disposed downstream of the masking material laminating roller 4 in the direction of the arrow A and above the position where the opening 108a of the strip-shaped sealing material 108L and the opening 8a of the strip-shaped masking material 8 are intermittently stopped. The masking material folding unit 5 has substantially the same shape and size as the opening 108a of the strip-shaped sealing material 108L, and includes a folding member 5a that can be inserted into the opening 108a, and a lifting mechanism 5b that lifts and lowers the folding member 5a between a standby position above the opening 108a and a folding position where the folding member 5a is inserted into the opening 108a. The masking material laminating roller 4 and the masking material folding unit 5 correspond to the masking means and masking step of the present invention.

[0041] 6, when strip-shaped sealing material 108L having strip-shaped mask material 8 laminated on its upper surface is intermittently conveyed and stops, mask material folding unit 5 lowers folding member 5a by lifting mechanism 5b to insert it into opening 108a, and folds inner peripheral edge 8c of opening 8a of strip-shaped mask material 8 into opening 108a of strip-shaped sealing material 108L. During the period when intermittent conveyance of strip-shaped sealing material 108L is stopped, mask material folding unit 5 raises folding member 5a by lifting mechanism 5b to remove it from inside opening 108a.

[0042] As a result, the inner peripheral edge 8c of the opening 8a of the strip-shaped mask material 8 is folded into the opening 108a of the strip-shaped sealing material 108L. In addition, since the opening 8a of the strip-shaped mask material 8 is smaller than the opening 108a of the strip-shaped sealing material 108L by the thickness T of the strip-shaped sealing material 108L, the entire side surface of the opening 108a of the strip-shaped sealing material 108L is covered by the inner peripheral edge 8c of the strip-shaped mask material 8. As a result, it is possible to prevent the positive electrode active material composition from entering between the opening 108a of the strip-shaped sealing material 108L and the inner peripheral edge 8c of the strip-shaped mask material 8.

[0043] Although the mask material folding section 5 is configured to automatically fold the belt-shaped mask material 8 using the folding member 5a and the lifting mechanism 5b, it may be configured to do this manually.

[0044] The positive electrode active material composition supplying section 6 is disposed downstream of the mask material folding section 5 in the direction of the arrow A and at a position where the opening 108a of the strip-shaped sealing material 108L is intermittently stopped. As shown in the cross-sectional view of FIG. 7, the positive electrode active material composition supplying section 6 includes a hopper 6a for storing the positive electrode active material composition 9, a feeder 6b for supplying the positive electrode active material composition 9 in the hopper 6a into the opening 108a of the strip-shaped sealing material 108L, a storage amount measuring device (storage amount measuring means) 6c for measuring the storage amount of the positive electrode active material composition 9 in the hopper 6a, and a feeder control section (feeder control means) 6d for controlling the supply amount of the positive electrode active material composition 9 by the feeder 6b based on the measurement result of the storage amount measuring device 6c. The positive electrode active material composition supplying section 6 corresponds to the supplying means and the supplying step of the present invention.

[0045] The hopper 6a is a box-shaped container and contains the positive electrode active material composition 9 therein. The feeder 6b is, for example, a belt feeder including a pair of rollers and a conveyor belt wound around the rollers, and conveys the positive electrode active material composition 9 in the hopper 6a to the discharge port 6e of the hopper 6a by the conveyor belt, and supplies the positive electrode active material composition 9 into the opening 108a of the strip-shaped sealing material 108L. The storage amount measuring device 6c is, for example, a level sensor that uses irradiation and reflection of laser light, and measures the storage amount of the positive electrode active material composition 9 in the hopper 6a.

[0046] Specifically, when the positive electrode active material composition 9 is supplied from the positive electrode active material composition supply unit 6 into the opening 108a of the strip-shaped sealing material 108L, the amount of the positive electrode active material composition 9 stored in the hopper 6a decreases, and the amount of decrease is measured by the storage amount measuring device 6c. The feeder control unit 6d determines whether or not an appropriate amount of the positive electrode active material composition 9 is supplied into the opening 108a based on the measurement result of the storage amount measuring device 6c.

[0047] When the feeder control unit 6d determines that the supply amount of the positive electrode active material composition 9 is small, it controls the feeder 6b to increase the supply amount of the positive electrode active material composition 9. Conversely, when the feeder control unit 6d determines that the supply amount of the positive electrode active material composition 9 is large, it controls the feeder 6b to decrease the supply amount of the positive electrode active material composition 9. This allows an appropriate amount of the positive electrode active material composition 9 to be supplied into the opening 108a of the strip-shaped sealing material 108L.

[0048] If the amount of positive electrode active material composition 9 supplied to the opening 108a is extremely less or more than a predetermined amount, the feeder control unit 6d may report to a higher-level control system that the positive electrode active material layer 103 formed in the opening 108a is an NG product, so that the positive electrode 101A can be removed from the product after its manufacture.

[0049] Next, a description will be given of the positive electrode active material composition 9. The positive electrode active material composition 9 contains positive electrode active material particles and an electrolyte solution.

[0050] Positive electrode active material particles include composite oxides of lithium and transition metals {composite oxides containing one type of transition metal (LiCoO2, LiNiO2, LiAlMnO4, LiMnO2, LiMn2O4, etc.), composite oxides containing two types of transition metal elements (e.g. LiFeMnO4, LiNi 1-x Co x O2, LiMn 1-y Co y O2, LiNi 1 / 3 Co 1 / 3 Al 1 / 3 O2 and LiNi 0.8 Co 0.15 Al 0.05 O2) and composite oxides containing three or more metal elements [e.g. LiM a M' b M'' c O2(M, M' and M'' are different transition metal elements and satisfy a+b+c=1. For example, LiNi 1 / 3 Mn 1 / 3 Co 1 / 3O2), etc.}, lithium-containing transition metal phosphates (e.g., LiFePO4, LiCoPO4, LiMnPO4, and LiNiPO4), transition metal oxides (e.g., MnO2 and V2O5), transition metal sulfides (e.g., MoS2 and TiS2), and conductive polymers (e.g., polyaniline, polypyrrole, polythiophene, polyacetylene, poly-p-phenylene, and polyvinylcarbazole), and two or more of them may be used in combination. Note that the lithium-containing transition metal phosphate may be one in which a part of the transition metal site is replaced with another transition metal.

[0051] From the viewpoint of the electrical characteristics of the battery, the volume average particle diameter of the positive electrode active material particles is preferably 0.01 to 100 μm, more preferably 0.1 to 35 μm, and even more preferably 2 to 30 μm.

[0052] The positive electrode active material particles may be coated positive electrode active material particles having at least a part of their surface covered with a coating material containing a polymer compound. When the positive electrode active material particles are coated with a coating material, the volume change of the positive electrode is mitigated, and the expansion of the positive electrode can be suppressed.

[0053] As the polymer compound constituting the coating material, those described as active material coating resins in JP2017-054703A, WO2015-005117A, and the like can be suitably used.

[0054] The coating material may contain a conductive agent, which may be the same as the conductive filler contained in the positive electrode current collector.

[0055] The electrolyte may include a solution containing an electrolyte and a non-aqueous solvent. The electrolyte may be any electrolyte used in known electrolytes, such as lithium salts of inorganic acids such as LiPF6, LiBF4, LiSbF6, LiAsF6, LiN(FSO2)2 and LiClO4, and lithium salts of organic acids such as LiN(CF3SO2)2, LiN(C2F5SO2)2 and LiC(CF3SO2)3, with LiN(FSO2)2 (also called LiFSI) being preferred.

[0056] The electrolyte concentration of the electrolytic solution is not particularly limited, but is preferably 0.5 to 5 mol / L, more preferably 0.8 to 4 mol / L, and further preferably 1 to 2 mol / L.

[0057] As the non-aqueous solvent, those used in known electrolytic solutions can be used, such as lactone compounds, cyclic or chain carbonates, chain carboxylates, cyclic or chain ethers, phosphates, nitrile compounds, amide compounds, sulfones, sulfolane, and mixtures thereof.

[0058] Examples of lactone compounds include 5-membered ring lactone compounds (such as γ-butyrolactone and γ-valerolactone) and 6-membered ring lactone compounds (such as δ-valerolactone).

[0059] Examples of cyclic carbonate esters include propylene carbonate, ethylene carbonate, butylene carbonate, etc. Examples of chain carbonate esters include dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, methyl-n-propyl carbonate, ethyl-n-propyl carbonate, di-n-propyl carbonate, etc.

[0060] Examples of chain carboxylates include methyl acetate, ethyl acetate, propyl acetate, and methyl propionate. Examples of cyclic ethers include tetrahydrofuran, tetrahydropyran, 1,3-dioxolane, and 1,4-dioxane. Examples of chain ethers include dimethoxymethane and 1,2-dimethoxyethane.

[0061] Examples of phosphate esters include trimethyl phosphate, triethyl phosphate, ethyl dimethyl phosphate, diethyl methyl phosphate, tripropyl phosphate, tributyl phosphate, tri(trifluoromethyl) phosphate, tri(trichloromethyl) phosphate, tri(trifluoroethyl) phosphate, tri(triperfluoroethyl) phosphate, 2-ethoxy-1,3,2-dioxaphospholan-2-one, 2-trifluoroethoxy-1,3,2-dioxaphospholan-2-one, and 2-methoxyethoxy-1,3,2-dioxaphospholan-2-one. Examples of the nitrile compound include acetonitrile, etc. Examples of the amide compound include DMF, etc. Examples of the sulfone include dimethyl sulfone and diethyl sulfone, etc. The non-aqueous solvent may be used alone or in combination of two or more.

[0062] Among non-aqueous solvents, lactone compounds, cyclic carbonates, chain carbonates and phosphates are preferred from the viewpoint of battery output and charge / discharge cycle characteristics, lactone compounds, cyclic carbonates and chain carbonates are more preferred, and a mixture of a cyclic carbonate and a chain carbonate is particularly preferred. Most preferred is a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC), or a mixture of ethylene carbonate (EC) and propylene carbonate (PC).

[0063] The positive electrode active material composition 9 may contain a conductive assistant. As the conductive assistant, a conductive material similar to the conductive filler contained in the positive electrode current collector can be suitably used. The conductive assistant is preferably contained in such a range that the weight ratio of the conductive assistant in the positive electrode active material layer when the positive electrode active material layer is formed is 3 to 10% by weight.

[0064] The positive electrode active material composition 9 preferably does not contain a binder. When the positive electrode active material composition 9 does not contain a binder, a non-bound positive electrode active material layer can be formed. Here, the non-bound positive electrode active material layer means that the positive electrode active material particles are not fixed in position by a binder (also called a binder), and the positive electrode active material particles are not irreversibly fixed to each other and to the current collector. When the positive electrode active material layer is a non-bound positive electrode active material layer, the positive electrode active material particles are not irreversibly fixed to each other, so that the interface between the positive electrode active material particles can be separated without mechanically destroying them, and even if stress is applied to the positive electrode active material layer, the positive electrode active material particles move, so that the destruction of the positive electrode active material layer can be prevented, which is preferable. In this specification, the binder means a chemical agent that cannot reversibly fix the positive electrode active material particles to each other or between the positive electrode active material particles and the current collector, and examples of such binders include known solvent-dried binders for lithium ion batteries such as starch, polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose, polyvinylpyrrolidone, tetrafluoroethylene, styrene-butadiene rubber, polyethylene, and polypropylene. These binders are used by dissolving or dispersing them in a solvent, and by volatilizing or distilling off the solvent, the surface becomes solidified without exhibiting adhesion, and therefore cannot reversibly fix the positive electrode active material particles to each other or between the positive electrode active material particles and the current collector.

[0065] The positive electrode active material composition 9 may contain an adhesive resin. As the adhesive resin, for example, a resin for coating a non-aqueous secondary battery active material described in JP 2017-054703 A in which a small amount of organic solvent is mixed to adjust the glass transition temperature to room temperature or lower, and a resin described as an adhesive in JP 10-255805 A can be suitably used. The adhesive resin means a resin that does not solidify even when the solvent component is evaporated and dried, and has adhesiveness (the property of adhering by applying a slight pressure without using water, solvent, heat, etc.). On the other hand, the solution-drying type electrode binder used as a binder means a material that dries and solidifies by evaporating the solvent component to firmly adhere and fix active material particles to each other. Therefore, the above-mentioned binder (solution-drying type electrode binder) and the adhesive resin are different materials.

[0066] Next, a description will be given of a negative electrode active material composition used in forming negative electrode active material layer 105 in an electrode manufacturing apparatus for negative electrode 101B. The negative electrode active material composition contains negative electrode active material particles and an electrolyte solution.

[0067] Examples of the negative electrode active material particles include carbon-based materials [graphite, non-graphitizable carbon, amorphous carbon, resin baked bodies (e.g., phenolic resin, furan resin, etc. baked and carbonized), cokes (e.g., pitch coke, needle coke, petroleum coke, etc.), and carbon fibers, etc.], silicon-based materials [silicon, silicon oxide (SiOx), silicon-carbon composites (carbon particles whose surfaces are coated with silicon and / or silicon carbide, silicon particles or silicon oxide particles whose surfaces are coated with carbon and / or silicon carbide, and silicon carbide, etc.), and silicon alloys (silicon-aluminum Examples of the negative electrode active material particles include aluminum alloys, silicon-lithium alloys, silicon-nickel alloys, silicon-iron alloys, silicon-titanium alloys, silicon-manganese alloys, silicon-copper alloys, and silicon-tin alloys, etc.), conductive polymers (e.g., polyacetylene and polypyrrole, etc.), metals (tin, aluminum, zirconium, and titanium, etc.), metal oxides (titanium oxide and lithium-titanium oxide, etc.), and metal alloys (e.g., lithium-tin alloys, lithium-aluminum alloys, and lithium-aluminum-manganese alloys, etc.), and mixtures of these with carbon-based materials. Among the above negative electrode active material particles, those that do not contain lithium or lithium ions inside may be subjected to a pre-doping process in which lithium or lithium ions are contained in part or all of the negative electrode active material particles in advance.

[0068] Among these, from the viewpoint of battery capacity and the like, carbon-based materials, silicon-based materials, and mixtures thereof are preferred, and as carbon-based materials, graphite, non-graphitizable carbon, and amorphous carbon are more preferred, and as silicon-based materials, silicon oxide and silicon-carbon composites are more preferred.

[0069] From the viewpoint of the electrical characteristics of the battery, the volume average particle diameter of the negative electrode active material particles is preferably 0.01 to 100 μm, more preferably 0.1 to 20 μm, and even more preferably 2 to 10 μm.

[0070] In this specification, the volume average particle diameter of the negative electrode active material particles means the particle diameter (Dv50) at an integrated value of 50% in the particle size distribution obtained by the Microtrack method (laser diffraction / scattering method). The Microtrack method is a method for determining the particle size distribution by utilizing scattered light obtained by irradiating particles with laser light. The volume average particle diameter can be measured using a Microtrack manufactured by Nikkiso Co., Ltd.

[0071] The negative electrode active material particles may be coated negative electrode active material particles having at least a part of their surface covered with a coating material containing a polymer compound. When the negative electrode active material particles are coated with the coating material, the volume change of the negative electrode is mitigated, and the expansion of the negative electrode can be suppressed.

[0072] As the coating material, the same coating material as that constituting the coated positive electrode active material particles can be suitably used.

[0073] The composition of the electrolyte solution may be the same as that contained in the positive electrode active material composition 9.

[0074] The negative electrode active material composition may contain a conductive assistant. As the conductive assistant, a conductive material similar to the conductive filler contained in the positive electrode active material composition 9 can be suitably used. It is preferable that the weight ratio of the conductive assistant in the negative electrode active material layer is in the range of 2 to 10% by weight.

[0075] The negative electrode active material composition may contain an adhesive resin. As the adhesive resin, the same adhesive resin as the optional component of the positive electrode active material composition 9 can be suitably used.

[0076] The negative electrode active material composition preferably does not contain a binder. When the negative electrode active material composition does not contain a binder, a non-binding negative electrode active material layer can be formed. The reason why the negative electrode active material layer is preferably a non-binding material is the same as the reason why the positive electrode active material layer is preferably a non-binding material.

[0077] The pressure / mask material removing roller 7a and the pressure receiving roller 7b are disposed downstream of the positive electrode active material composition supplying section 6 in the direction of the arrow A. The pressure / mask material removing roller 7a is disposed so as to abut against the upper surface of the band-shaped mask material 8. The pressure receiving roller 7b is disposed so as to abut against the lower surface of the band-shaped positive electrode current collector 102L at a position facing the pressure / mask material removing roller 7a. The pressure / mask material removing roller 7a and the pressure receiving roller 7b compress the positive electrode active material composition 9 supplied into the opening 108a of the band-shaped sealing material 108L to form the positive electrode active material layer 103. The pressure / mask material removing roller 7a and the pressure receiving roller 7b correspond to the compression means and the compression step of the present invention. The pressure / mask material removing roller 7a corresponds to the mask removing means and the mask removing step of the present invention.

[0078] The thickness of the positive electrode active material layer 103 is not particularly limited, but from the viewpoint of battery performance, it is preferably 150 to 600 μm, and more preferably 200 to 450 μm.

[0079] The speed at which the positive electrode active material composition 9 is compressed by the pressure / mask material removal roller 7a and the pressure receiving roller 7b is not particularly limited, but can be appropriately set to a speed at which bending or wrinkling does not occur in the strip-shaped sealing material 108L, the strip-shaped positive electrode current collector 102L, and the positive electrode active material layer 103. For example, from the viewpoint of maintaining a sufficient compression retention time, the speed is preferably 1 to 20 m / min.

[0080] The linear pressure applied to the positive electrode active material composition 9 by the pressure / mask material removing roller 7a and the pressure receiving roller 7b is preferably 35 to 3500 N / cm. The linear pressure applied to the positive electrode active material composition 9 means a linear pressure calculated from the load measured by a load cell attached to the pressure / mask material removing roller 7a and the pressure receiving roller 7b, and the thickness of the compressed positive electrode active material layer 103.

[0081] As shown in the cross-sectional views of FIGS. 8(A) and 8(B), the pressure / mask material removal roller 7a also functions as a guide roller for guiding the strip-shaped mask material 8 when removing the strip-shaped mask material 8 from the upper surface of the strip-shaped sealing material 108L. On the upper surface of the strip-shaped mask material 8, the positive electrode active material composition 9 spilled when the positive electrode active material composition 9 is supplied from the positive electrode active material composition supply unit 6 into the opening 108a of the strip-shaped sealing material 108L is scattered. However, since the positive electrode active material composition 9 is removed together with the strip-shaped mask material 8, it does not remain on the upper surface of the strip-shaped sealing material 108L. In addition, the folded inner peripheral edge 8c of the opening 8a of the strip-shaped mask material 8 prevents the positive electrode active material composition 9 from crumbling and sliding down onto the strip-shaped sealing material 108L when the strip-shaped mask material 8 is removed from the strip-shaped sealing material 108L, so that it is possible to effectively suppress the positive electrode active material composition 9 from remaining on the upper surface of the strip-shaped sealing material 108L.

[0082] Although not shown in detail, downstream of the pressure / mask material removing roller 7a and the pressure receiving roller 7b in the direction of the arrow A, a cutting section is provided for cutting the strip-shaped sealing material 108L and the strip-shaped positive electrode current collector 102L between the openings 108a to form a plurality of positive electrodes 101A. This makes it possible to continuously manufacture a plurality of positive electrodes 101A from the strip-shaped sealing material 108L, the strip-shaped positive electrode current collector 102L, and the positive electrode active material composition 9. Although not described in detail, the negative electrode 101B is also manufactured in the same manner as the positive electrode 101A by an electrode manufacturing apparatus for negative electrodes.

[0083] Positive electrode 101A manufactured by electrode manufacturing apparatus 1 is combined with separator 106 and negative electrode 101B to manufacture lithium ion battery 101. When combining positive electrode 101A, negative electrode 101B, and separator 106, the above-mentioned electrolyte solution may be injected separately.

[0084] The material of the separator 106 is not particularly limited, and examples of the material that can be used include separators that are known to be used in lithium ion batteries, such as porous films made of polyethylene or polypropylene, laminated films of the above-mentioned porous films (such as laminated films of porous polyethylene films and porous polypropylene), nonwoven fabrics made of synthetic fibers (such as polyester fibers and aramid fibers) or glass fibers, and those having ceramic particles such as silica, alumina, and titania attached to their surfaces.

[0085] In addition, in order to combine the positive electrode 101A and the negative electrode 101B, the sealing material 108 of the positive electrode 101A and the sealing material 109 of the negative electrode 101B are bonded together. When a thermosetting polymer material is used for the sealing materials 108 and 109, the sealing materials 108 and 109 can be bonded together by applying heat to them using an impulse sealer or the like.

[0086] Next, a method for manufacturing an electrode for a lithium ion battery using the electrode manufacturing apparatus 1 described above will be described with reference to the flowchart of FIG.

[0087] The electrode manufacturing apparatus 1 utilizes the conveying roller 2 or the like to convey and supply the strip-shaped sealing material 108L, in which a plurality of openings 108a are formed at predetermined intervals, in the direction of the arrow A (step S1). Next, the current collector laminating roller 3 guides the strip-shaped positive electrode current collector 102L to laminate it under the strip-shaped sealing material 108L (step S2). In addition, the mask material laminating roller 4 guides the strip-shaped mask material 8, in which a plurality of openings 8a and slits 8b are formed at predetermined intervals, to laminate it on top of the strip-shaped sealing material 108L (step S3). The strip-shaped sealing material 108L, the strip-shaped positive electrode current collector 102L, and the strip-shaped mask material 8 are intermittently conveyed in the direction of the arrow A by rollers such as the conveying roller 2 in a laminated state.

[0088] When the transport of the strip-shaped sealing material 108L and the like is stopped due to intermittent transport, the electrode manufacturing apparatus 1 folds the inner edge of the opening 8a of the strip-shaped mask material 8 into the opening 108a of the strip-shaped sealing material 108L using the mask material folding section 5 (step S4).

[0089] In the electrode manufacturing apparatus 1, the positive electrode active material composition supplying unit 6 supplies the positive electrode active material composition into the opening 108a of the strip-shaped sealing material 108L at a timing when the strip-shaped sealing material 108L and the like are being transported by intermittent transport (step S5). In this step S5, when the positive electrode active material composition 9 stored in the hopper 6a is supplied by the feeder 6b into the opening 108a of the strip-shaped sealing material 108L, the amount of the positive electrode active material composition 9 stored in the hopper 6a is measured by the storage amount measuring device 6c, and the supply amount of the positive electrode active material composition 9 by the feeder 6b is controlled based on the measurement result.

[0090] In the electrode manufacturing apparatus 1, while the strip-shaped sealing material 108L and the like are being transported by intermittent transport, the pressure / mask material removal roller 7a and the pressure receiving roller 7b compress the positive electrode active material composition 9 supplied into the opening 108a of the strip-shaped sealing material 108L, thereby forming a positive electrode active material layer 103 (step S6).

[0091] The pressure / mask material removing roller 7a guides the strip-shaped mask material 8 to remove it from the upper surface of the strip-shaped sealing material 108L (step S7). At that time, the positive electrode active material composition 9 spilled onto the strip-shaped mask material 8 is removed together with the strip-shaped mask material 8. The folded-in inner peripheral edge 8c of the opening 8a of the strip-shaped mask material 8 prevents the positive electrode active material composition 9 from crumbling and sliding down onto the strip-shaped sealing material 108L when the strip-shaped mask material 8 is removed from the strip-shaped sealing material 108L.

[0092] The electrode manufacturing apparatus 1 cuts the strip-shaped sealing material 108L and the strip-shaped positive electrode current collector 102L between the openings 108a using a cutting unit (not shown) at a timing when the transport of the strip-shaped sealing material 108L and the like is stopped due to the intermittent transport, thereby forming a plurality of positive electrodes 101A (step S8).

[0093] As described above, according to the electrode manufacturing apparatus 1 and the electrode manufacturing method of this embodiment, the strip-shaped mask material 8 having the opening 8a slightly smaller than the opening 108a of the strip-shaped sealing material 108L is laminated on the upper surface of the strip-shaped sealing material 108L, and the inner peripheral edge 8c of the opening 8a of the strip-shaped mask material 8 is folded into the opening 108a of the strip-shaped sealing material 108L. Therefore, when the strip-shaped mask material 8 is removed from the strip-shaped sealing material 108L, the positive electrode active material composition 9 spilled onto the strip-shaped mask material 8 can be collected together, so that it is possible to prevent the positive electrode active material composition 9 from remaining on the upper surface of the strip-shaped sealing material 108L. In addition, when the strip-shaped mask material 8 is removed from the strip-shaped sealing material 108L, the folded inner peripheral edge 8c of the strip-shaped mask material 8 prevents the positive electrode active material composition 9 from crumbling and sliding down onto the strip-shaped sealing material 108L, so that it is possible to effectively prevent the positive electrode active material composition 9 from remaining on the upper surface of the strip-shaped sealing material 108L.

[0094] Furthermore, according to the electrode manufacturing apparatus 1 and the electrode manufacturing method of this embodiment, slits 8b are formed at the corners of the opening 8a of the strip-shaped mask material 8, and the inner peripheral edge 8c of the opening 8a of the strip-shaped mask material 8 can be easily folded into the opening 108a of the strip-shaped sealing material 108L by using the slits 8b. Furthermore, since the slits 8b are used for folding, it is possible to prevent wrinkles and the like from occurring in the strip-shaped mask material 8 folded into the opening 108a of the strip-shaped sealing material 108L.

[0095] Furthermore, according to the electrode manufacturing apparatus 1 and the electrode manufacturing method of this embodiment, the opening 8a of the strip-shaped mask material 8 is smaller than the opening 108a of the strip-shaped sealing material 108L by the thickness of the strip-shaped sealing material 108L, so that the side of the opening 108a of the strip-shaped sealing material 108L can be covered by the folded inner peripheral edge 8c of the strip-shaped mask material 8. This makes it possible to prevent the positive electrode active material composition 9 from entering between the opening 108a of the strip-shaped sealing material 108L and the inner peripheral edge 8c of the strip-shaped mask material 8, and to appropriately supply the positive electrode active material composition 9 into the opening 108a of the strip-shaped sealing material 108L.

[0096] According to the electrode manufacturing apparatus 1 and the electrode manufacturing method of this embodiment, when the positive electrode active material composition 9 stored in the hopper 6a is supplied to the opening 108a of the strip-shaped sealing material 108L by the feeder 6b, the amount of the positive electrode active material composition 9 stored in the hopper 6a is measured by the storage amount measuring device 6c, and the amount of the positive electrode active material composition 9 supplied by the feeder 6b is controlled based on the measurement result, so that it is possible to supply an appropriate amount of the positive electrode active material composition 9 to the opening 108a of the strip-shaped sealing material 108L. Also, if the amount of the positive electrode active material composition 9 supplied to the opening 108a is extremely less or more than a predetermined amount, the positive electrode active material layer 103 formed in the opening 108a can be determined to be a defective product and can be removed from the product, so that it is possible to improve the yield rate of the lithium ion battery electrodes manufactured.

[0097] Although the embodiment of the present invention has been described above, the specific configuration is not limited to the above embodiment, and even if there are design changes within the scope of the present invention, they are included in the present invention. For example, in the above embodiment, the long strip-shaped sealing material 108L, the strip-shaped positive electrode current collector 102L, and the strip-shaped mask material 8 are used to manufacture the positive electrode 101A, but the sealing material, the positive electrode current collector, and the mask material cut to a predetermined size in advance may be laminated to manufacture the positive electrode 101A.

[0098] The above-described embodiments include the inventions described in claims 2 to 7. The invention described in claim 2 is characterized in that, in the method for manufacturing an electrode for a lithium ion battery described in claim 1, the opening of the sealing material and the opening of the mask material are polygonal, and slits are formed at corners of the opening of the mask material. According to the invention described in claim 2, the inner peripheral edge of the opening of the mask material can be easily folded into the opening of the sealing material by using the slits. In addition, since the mask material is folded into the opening of the sealing material by using the slits, it is possible to prevent wrinkles from occurring in the mask material folded into the opening of the sealing material.

[0099] The invention of claim 3 is characterized in that, in the method for manufacturing an electrode for a lithium ion battery of claim 1 or 2, the opening of the mask material is smaller than the opening of the sealant by the thickness of the sealant. According to the invention of claim 3, the side of the opening of the sealant can be covered by the folded inner peripheral edge of the opening of the mask material. This makes it possible to prevent the electrode active material composition from entering between the opening of the sealant and the inner peripheral edge of the mask material, and to appropriately supply the electrode active material composition into the opening of the sealant.

[0100] The invention of claim 4 is characterized in that, in the method for producing an electrode for a lithium ion battery according to claim 1 or 2, the supply step includes a step of measuring the amount of the electrode active material composition stored in the hopper by a storage amount measuring means when the electrode active material composition stored in the hopper is supplied into the opening of the sealing material by a feeder, and a step of controlling the supply amount of the electrode active material composition by the feeder based on the measurement result of the storage amount measuring means. According to the invention of claim 4, it is possible to supply an appropriate amount of the electrode active material composition into the opening of the sealing material. In addition, when the supply amount of the electrode active material composition to the opening is extremely less or more than a predetermined amount, it is possible to determine that the electrode active material layer formed in the opening is a defective product and to remove it from the product, so that it is possible to improve the yield rate of the lithium ion battery electrodes produced.

[0101] The invention described in claim 5 is a manufacturing device for an electrode for a lithium ion battery, comprising a sealant having an opening, an electrode current collector laminated on the lower surface of the sealant to close the opening, and an electrode active material layer provided in the opening, and further comprising: a masking means for laminating a masking material having an opening slightly smaller than the opening of the sealant on the upper surface of the sealant and folding the inner peripheral edge of the opening of the masking material into the opening of the sealant, a supplying means for supplying an electrode active material composition containing electrode active material particles into the opening of the sealant, a compressing means for compressing the electrode active material composition to form the electrode active material layer, and a mask removing means for removing the masking material from the upper surface of the sealant. According to the invention described in claim 5, the electrode active material composition spilled onto the masking material when the masking material is removed from the sealant can be collected together, so that it is possible to prevent the electrode active material composition from remaining on the upper surface of the sealant. Furthermore, when the mask material is removed from the sealing material, the folded inner edge of the mask material prevents the electrode active material composition from crumbling and sliding down onto the sealing material, thereby making it possible to effectively suppress the electrode active material composition from remaining on the upper surface of the sealing material.

[0102] The invention described in claim 6 is characterized in that, in the manufacturing apparatus for lithium ion battery electrodes described in claim 5, the supplying means includes a hopper for storing the electrode active material composition, a feeder for supplying the electrode active material composition supplied from the hopper into the opening of the sealing material, a storage amount measuring means for measuring the storage amount of the electrode active material composition in the hopper, and a feeder control means for controlling the supply amount of the electrode active material composition by the feeder based on the measurement result of the storage amount measuring means. According to the invention described in claim 6, it is possible to supply an appropriate amount of the electrode active material composition into the opening of the sealing material. In addition, if the supply amount of the electrode active material composition to the opening is extremely less or more than a predetermined amount, it is possible to determine that the electrode active material layer formed in the opening is a defective product and to remove it from the product, so that it is possible to improve the yield rate of the lithium ion battery electrodes manufactured. [Explanation of symbols]

[0103] 1. Lithium-ion battery electrode manufacturing equipment (electrode manufacturing equipment) 2 Conveyor roller 3 Current collector stacking roller 4 Masking material laminating roller (masking means) 5 Masking material folding section (masking means) 5a Folding member 5b Lifting mechanism 6 Positive electrode active material composition supply section (supply means) 6a Hopper 6b Feeder 6c Storage volume measuring device (storage volume measuring means) 6d Feeder control section (feeder control means) 7a Pressure / mask material removal roller (pressure means, mask removal means) 7b Pressure receiving roller (pressure means) 8. Strip mask material 8a opening 8b Slit 8c Inner rim 9 Cathode active material composition 101 Lithium-ion battery 101A positive electrode 101B Negative electrode 102 Positive electrode current collector 103 Cathode active material layer 104 Negative electrode current collector 105 Negative electrode active material layer 106 Separator 107, 108, 109 Encapsulating materials 102L Strip-shaped positive electrode current collector 108L Strip-shaped sealing material 108a opening

Claims

1. A method for manufacturing an electrode for a lithium ion battery, comprising: a sealant having an opening; an electrode current collector laminated on a lower surface of the sealant to close the opening; and an electrode active material layer provided in the opening, a masking step of laminating a mask material having an opening slightly smaller than the opening of the sealing material on an upper surface of the sealing material and folding an inner peripheral edge of the opening of the mask material into the opening of the sealing material; a supplying step of supplying an electrode active material composition containing electrode active material particles into the opening of the sealant; a compressing step of compressing the electrode active material composition to form the electrode active material layer; a mask removing step of removing the mask material from an upper surface of the sealing material; A method for manufacturing an electrode for a lithium ion battery, comprising:

2. the opening of the sealing material and the opening of the mask material are polygonal, and slits are formed at corners of the opening of the mask material; The method for producing an electrode for a lithium ion battery according to claim 1 .

3. the opening of the mask material is smaller than the opening of the sealing material by the thickness of the sealing material; The method for producing an electrode for a lithium ion battery according to claim 1 or 2.

4. The supplying step includes: a step of measuring an amount of the electrode active material composition stored in the hopper by a storage amount measuring means when the electrode active material composition stored in the hopper is supplied into an opening of the sealing material by a feeder; A step of controlling the supply amount of the electrode active material composition by the feeder based on the measurement result of the storage amount measuring means; 3. The method for producing an electrode for a lithium ion battery according to claim 1, further comprising the steps of:

5. An apparatus for manufacturing an electrode for a lithium ion battery, the apparatus comprising: a sealant having an opening; an electrode current collector laminated on a lower surface of the sealant to close the opening; and an electrode active material layer provided within the opening, a masking means for laminating a masking material having an opening slightly smaller than the opening of the sealing material on an upper surface of the sealing material and folding an inner peripheral edge of the opening of the masking material into the opening of the sealing material; A supplying means for supplying an electrode active material composition containing electrode active material particles into the opening of the sealing material; a compression means for compressing the electrode active material composition to form the electrode active material layer; a mask removing means for removing the mask material from the upper surface of the sealing material; 1. A manufacturing apparatus for an electrode for a lithium ion battery, comprising:

6. The supply means is A hopper for storing the electrode active material composition; a feeder that supplies the electrode active material composition supplied from the hopper into an opening of the sealing material; A storage amount measuring means for measuring the storage amount of the electrode active material composition in the hopper; a feeder control means for controlling the amount of the electrode active material composition supplied by the feeder based on the measurement result of the storage amount measurement means; 6. The manufacturing apparatus for an electrode for a lithium ion battery according to claim 5, further comprising:

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