Living Substance Processing Apparatus, Battery Electrode Manufacturing Apparatus, Living Substance Processing Method, and Battery Electrode Manufacturing Method

Abstract

To provide an active material treatment device, a battery electrode manufacturing device, an active material treatment method, and a battery electrode manufacturing method, which are capable of properly collecting active materials scattered into the interior of a chamber.SOLUTION: An active material treatment device 100 includes: a chamber 110 for handling a powdery active material 32A in an interior IN thereof; a metal foil layer 140 provided to be insulated from an inner surface 111a of the chamber 110 and covering the inner surface 111a; a charging device 141 that is provided in the interior IN of the chamber 110, and charges particles of the active material 32A in the air in the interior IN of the chamber 110 and the metal foil layer 140 to the same polarity; and an exhaust device 142 for exhausting the air in the interior IN of the chamber 110.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a living substance processing device, a battery electrode manufacturing device, a living substance processing method, and a battery electrode manufacturing method.

Background Art

[0002] For example, Patent Document 1 discloses a dust collection device for a machining center. This dust collection device includes an overall cover for preventing scattering that entirely covers the sliding part of the table, and this overall cover prevents abrasive grains and dust from scattering to the outside. Further, for example, Patent Document 2 discloses a linear motion mechanism. This linear motion mechanism includes a first cover that covers the movable part and a second cover having a structure that overlaps with the first cover, and even when installed in an environment where droplets and dust are scattered, entry of droplets and dust into the movable part is prevented.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, a lithium-ion battery that has recently attracted attention is generally configured by laminating a plurality of electrodes in which an active material layer is formed on the surface of a current collector via a separator. There is an idea of manufacturing such an electrode for a lithium-ion battery, for example, by supplying and fixing a powdery active material on a current collector in a chamber. In this case, there is a risk that fine particles of the active material will scatter inside during the manufacture of the electrode, and the fine particles of the active material will adhere to the inner surface of the chamber. On the other hand, for example, when collecting fine particles of the active material scattered inside the chamber, it cannot be said that the techniques disclosed in Patent Document 1 and Patent Document 2 mentioned above are suitable configurations, and there is room for further improvement.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide an active material processing apparatus, a battery electrode manufacturing apparatus, an active material processing method, and a battery electrode manufacturing method capable of appropriately collecting the active material scattered inside the chamber.

Means for Solving the Problems

[0006] To achieve the above object, an active material processing apparatus according to the present invention includes a chamber that handles a powdery active material inside, a metal foil layer that is provided insulated from the inner surface of the chamber and covers the inner surface, a charging device that is provided inside the chamber and charges the particles of the active material in the air inside the chamber and the metal foil layer to the same polarity, and an exhaust device that exhausts the air inside the chamber.

Effects of the Invention

[0007] The active material processing apparatus, battery electrode manufacturing apparatus, active material processing method, and battery electrode manufacturing method according to the present invention have the effect of being able to appropriately collect the active material scattered inside the chamber.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited by this embodiment. Also, the constituent elements in the following embodiments include those that can be replaced by those skilled in the art and are easy to replace, or those that are substantially the same.

[0010] [Embodiment] The manufacturing apparatus 100 according to the present embodiment shown in FIG. 2 is a battery electrode manufacturing apparatus for manufacturing the electrode 30 applied to the single battery 10 shown in FIG. 1. Hereinafter, first, after explaining the basic configuration of the single battery 10 and the electrode 30 with reference to FIG. 1, the manufacturing apparatus 100 will be described in detail with reference to FIG. 2 and the like.

[0011] [Single Battery] The single battery (also referred to as a battery cell or a single cell) 10 of the present embodiment shown in FIG. 1 is a lithium-ion secondary battery which is a type of non-aqueous electrolyte secondary battery. A lithium-ion secondary battery is a secondary battery that charges and discharges by the movement of lithium ions between the positive electrode 30a and the negative electrode 30b. In the following description, when there is no need to particularly distinguish between the "positive electrode 30a" and the "negative electrode 30b", they may simply be referred to as the "electrode 30".

[0012] The single cell 10 includes a positive electrode 30a, a negative electrode 30b, a separator 40, and a frame body 50. The positive electrode 30a is composed of a positive electrode current collector layer 31a and a positive electrode active material layer 32a. On the other hand, the negative electrode 30b is composed of a negative electrode current collector layer 31b and a negative electrode active material layer 32b. In the single cell 10, the positive electrode current collector layer 31a, the positive electrode active material layer 32a, the separator 40, the negative electrode active material layer 32b, and the negative electrode current collector layer 31b are laminated in this order. That is, in the single cell 10, the positive electrode current collector layer 31a and the negative electrode active material layer 32b are arranged on the outermost layers. And, at the edges of the positive electrode current collector layer 31a and the negative electrode current collector layer 31b, the outer peripheries of the positive electrode active material layer 32a, the negative electrode active material layer 32b, and the separator 40 are sealed by the frame body 50, and the electrolyte is enclosed. In this state, in the single cell 10, the separator 40 is interposed between the positive electrode active material layer 32a and the negative electrode active material layer 32b, and the separator 40 functions as a partition between the positive electrode 30a and the negative electrode 30b. The single cell 10 can be used, for example, in the form of a battery module in which a plurality of single cells are combined and modularized, or a battery pack in which a plurality of such battery modules are combined to adjust the voltage and capacity.

[0013] In the following description, when it is not necessary to particularly distinguish between the "positive electrode current collector layer 31a" and the "negative electrode current collector layer 31b", they may simply be referred to as the "current collector layer 31". Similarly, when it is not necessary to particularly distinguish between the "positive electrode active material layer 32a" and the "negative electrode active material layer 32b", they may simply be referred to as the "electrode active material layer 32".

[0014] <Specific Example of Positive Electrode Current Collector> As the positive electrode current collector constituting the positive electrode current collector layer 31a, a current collector used in a known lithium ion single cell can be used. For example, a resin current collector composed of a known metal current collector and a conductive material and a resin (such as the resin current collector described in JP-A-2012-150905 and WO 2015 / 005116) can be used. From the viewpoint of battery characteristics and the like, the positive electrode current collector constituting the positive electrode current collector layer 31a is preferably a resin current collector.

[0015] 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, and alloys containing one or more of these metals, and stainless alloys. These metal materials may be used in the form of thin plates or metal foils. Alternatively, a substrate surface composed of a material other than the above metal material with the above metal material formed thereon by methods such as sputtering, electrodeposition, or coating may be used as the metal current collector.

[0016] The resin current collector preferably contains a conductive filler and a matrix resin. Examples of the matrix resin include polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), etc., but are not particularly limited. The conductive filler is not particularly limited as long as it is selected from materials having conductivity. For example, the conductive filler may be a conductive fiber having a fibrous shape.

[0017] In addition to the matrix resin and the conductive filler, the resin current collector may contain other components (dispersants, crosslinking accelerators, crosslinking agents, colorants, ultraviolet absorbers, plasticizers, etc.). Further, a plurality of resin current collectors may be laminated and used, or a resin current collector and a metal foil may be laminated and used.

[0018] The thickness of the positive electrode current collector layer 31a is not particularly limited, but is preferably 5 to 150 μm. When a plurality of resin current collectors are laminated and used as the positive electrode current collector layer 31a, the total thickness after lamination is preferably 5 to 150 μm. The positive electrode current collector layer 31a can be obtained, for example, by molding a conductive resin composition obtained by melt-kneading a matrix resin, a conductive filler, and, if necessary, a dispersant for the filler into a film shape by a known method.

[0019] <Specific examples of the positive electrode active material> The positive electrode active material layer 32a is preferably a non-binder body of a mixture containing a positive electrode active material. Here, the non-binder body means that the position of the positive electrode active material in the positive electrode active material layer is not fixed, and the positive electrode active materials and the positive electrode active materials and the positive electrode active material and the current collector are not irreversibly fixed. When the positive electrode active material layer 32a is a non-binder body, since the positive electrode active materials are not irreversibly fixed, the interface between the positive electrode active materials can be separated without mechanically destroying it, and even when stress is applied to the positive electrode active material layer 32a, the positive electrode active material can move to prevent the destruction of the positive electrode active material layer 32a, which is preferable. The non-binder positive electrode active material layer 32a can be obtained by a method such as making the positive electrode active material layer 32a into a positive electrode active material layer containing a positive electrode active material and an electrolytic solution and not containing a binder. In this specification, the binder means a drug that cannot reversibly fix the positive electrode active materials and the positive electrode active material and the current collector, and examples include known solvent-drying type 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 being dissolved or dispersed in a solvent, and solidify without showing adhesiveness on the surface by volatilizing and distilling off the solvent, so they cannot reversibly fix the positive electrode active materials and the positive electrode active material and the current collector.

[0020] Examples of the positive electrode active material include, but are not particularly limited to, composite oxides of lithium and transition metals, composite oxides having two transition metal elements, and composite oxides having three or more metal elements.

[0021] The positive electrode active material may be a coated positive electrode active material in which at least a part of its surface is coated with a coating material containing a polymer compound. When the periphery of the positive electrode active material is coated with a coating material, the volume change of the positive electrode can be alleviated, and the expansion of the positive electrode can be suppressed.

[0022] As the polymer compound constituting the coating material, those described as resins for active material coating in JP-A-2017-054703 and WO 2015 / 005117 etc. can be preferably used.

[0023] The coating material may contain a conductive agent. As the conductive agent, the same ones as the conductive fillers contained in the positive electrode current collector layer 31a can be preferably used.

[0024] The positive electrode active material layer 32a may contain an adhesive resin. As the adhesive resin, for example, those obtained by mixing a small amount of an organic solvent with the resin for non-aqueous secondary battery active material coating described in JP-A-2017-054703 and adjusting its glass transition temperature to room temperature or lower, and those described as adhesives in JP-A-10-255805 etc. can be preferably used. Note that the adhesive resin means a resin that has adhesiveness (the property of adhering by applying a slight pressure without using water, a solvent, heat, etc.) without solidifying even when the solvent component is volatilized and dried. On the other hand, the solution-drying type electrode binder used as a binder means one that dries and solidifies by volatilizing the solvent component to firmly adhere and fix the active materials together. Therefore, the above-described binder (solution-drying type electrode binder) and the adhesive resin are different materials.

[0025] The positive electrode active material layer 32a may contain an electrolytic solution containing an electrolyte and a non-aqueous solvent. As the electrolyte, those used in known electrolytic solutions etc. can be used. As the non-aqueous solvent, those used in known electrolytic solutions (for example, phosphate esters, nitrile compounds, etc. and mixtures thereof etc.) can be used. For example, a mixed solution of ethylene carbonate (EC) and dimethyl carbonate (DMC), or a mixed solution of ethylene carbonate (EC) and propylene carbonate (PC) can be used.

[0026] The positive electrode active material layer 32a may contain a conductive aid. As the conductive aid, the same conductive materials as the conductive fillers contained in the positive electrode current collector layer 31a can be preferably used.

[0027] The thickness of the positive electrode active material layer 32a 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.

[0028] <Specific examples of the negative electrode current collector> As the negative electrode current collector constituting the negative electrode current collector layer 31b, the same ones as the configurations described for the positive electrode current collector can be appropriately selected and used, and can be obtained by the same method. The negative electrode current collector layer 31b is preferably a resin current collector from the viewpoint of battery characteristics and the like. The thickness of the negative electrode current collector layer 31b is not particularly limited, but is preferably 5 to 150 μm.

[0029] <Specific examples of the negative electrode active material> The negative electrode active material layer 32b is preferably a non-binder of a mixture containing a negative electrode active material. The reason why the negative electrode active material layer is preferably a non-binder, and the method for obtaining the non-binder negative electrode active material layer 32b are the same as the reason why the positive electrode active material layer 32a is preferably a non-binder and the method for obtaining the non-binder positive electrode active material layer 32a.

[0030] As the negative electrode active material, for example, carbon-based materials, silicon-based materials, and mixtures thereof can be used, but it is not particularly limited.

[0031] The negative electrode active material may be a coated negative electrode active material in which at least a part of its surface is coated with a coating material containing a polymer compound. When the periphery of the negative electrode active material is coated with a coating material, the volume change of the negative electrode can be alleviated, and the expansion of the negative electrode can be suppressed.

[0032] As the coating material, the same ones as the coating materials constituting the coated positive electrode active material can be preferably used.

[0033] The negative electrode active material layer 32b contains an electrolytic solution containing an electrolyte and a non-aqueous solvent. As the composition of the electrolytic solution, the same electrolytic solution as the electrolytic solution contained in the positive electrode active material layer 32a can be preferably used.

[0034] The negative electrode active material layer 32b may contain a conductive assistant. As the conductive assistant, a conductive material similar to the conductive filler contained in the positive electrode active material layer 32a can be preferably used.

[0035] The negative electrode active material layer 32b may contain an adhesive resin. As the adhesive resin, a similar one to the adhesive resin which is an optional component of the positive electrode active material layer 32a can be preferably used.

[0036] The thickness of the negative electrode active material layer 32b 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.

[0037] <Specific examples of the separator> Examples of the electrolyte held by the separator 40 include an electrolytic solution or a gel polymer electrolyte. By using these electrolytes, the separator 40 ensures high lithium ion conductivity. Examples of the form of the separator 40 include a porous film made of polyethylene or polypropylene, etc., but it is not particularly limited.

[0038] <Specific examples of the frame body> The frame body 50 is not particularly limited as long as it is a material durable against the electrolytic solution. For example, a polymer material is preferable, and a thermosetting polymer material is more preferable. The material constituting the frame body 50 may be any material having insulation, sealing (liquid tightness), heat resistance at the battery operating temperature, etc., and a resin material is preferably adopted. More specifically, examples of the frame body 50 include epoxy resins, polyolefin resins, polyurethane resins, and polyvinylidene fluoride resins. Among them, epoxy resins are preferable because of their high durability and ease of handling.

[0039] <Basic configuration of the manufacturing apparatus> Next, with reference to FIGS. 2 and 3, the schematic configuration of the manufacturing apparatus 100 will be described. The manufacturing apparatus 100 manufactures the above-described electrode 30. This manufacturing apparatus 100 may be realized, for example, by being incorporated into a battery manufacturing apparatus that manufactures the single cell 10. Note that the current collector 31A described below constitutes the current collector layer 31 (the positive electrode current collector layer 31a and the negative electrode current collector layer 31b) described above. On the other hand, the active material 32A constitutes the electrode active material layer 32 (the positive electrode active material layer 32a and the negative electrode active material layer 32b) described above.

[0040] Here, generally, when the electrode 30 is formed by applying the powdery active material 32A onto one surface of the current collector 31A, which is a base film, in the atmospheric pressure, air may remain inside the active material 32A. Then, if press molding is performed on the active material 32A in this state, after the pressing is completed, the compressed air expands, and phenomena such as the active material 32A flying off or the surface of the active material 32A becoming uneven may occur.

[0041] On the other hand, the manufacturing apparatus 100 of the present embodiment is configured to manufacture the electrode 30 by supplying the powdery active material 32A onto the belt-shaped current collector 31A inside the chamber 110 whose pressure is reduced from the atmospheric pressure.

[0042] With this configuration, the manufacturing apparatus 100 of the present embodiment suppresses the remaining air inside the active material 32A and realizes an improvement in the uniformity of the electrode active material layer 32 formed on the current collector layer 31. Hereinafter, the specific configuration of each part of the manufacturing apparatus 100 for realizing this will be described.

[0043] As described above, although the positive electrode 30a and the negative electrode 30b are different in the materials constituting the current collector layer 31 (positive electrode current collector layer 31a, negative electrode current collector layer 31b) and the electrode active material layer 32 (positive electrode active material layer 32a, negative electrode active material layer 32b), there is no difference in that the electrode active material layer 32 is electrically bonded to one surface of the current collector layer 31 in each case. Therefore, in the following description, when there is no need to particularly distinguish between the manufacture of the "positive electrode 30a" and the manufacture of the "negative electrode 30b", it will simply be described as the manufacture of the "electrode 30".

[0044] Specifically, as shown in FIG. 2, the manufacturing apparatus 100 includes a chamber 110, an active material supply device 120, and a roll press 130. A part of the active material supply device 120 and the roll press 130 constitute an electrode forming unit 100A. The electrode forming unit 100A is a part of the manufacturing apparatus 100 where the powdery active material 32A is supplied onto the current collector 31A to form the electrode 30. The active material 32A is applied onto the current collector 31A, and the active material 32A is compressed to form the electrode active material layer 32 and form the electrode 30. As described above, in the present embodiment, the electrode forming unit 100A is provided in a reduced-pressure environment inside the chamber 110 IN.

[0045] In the following description, in the manufacturing apparatus 100, the direction in which the current collector 31A is conveyed may be referred to as the "conveying direction D1". The conveying direction D1 typically extends substantially horizontally and corresponds to the longitudinal direction of the belt-shaped current collector 31A. In the chamber 110 of the manufacturing apparatus 100, the active material supply device 120 and the roll press 130 are arranged in this order from the upstream side to the downstream side in the conveying direction D1.

[0046] Chamber 110 is a container in which the internal IN is depressurized relative to atmospheric pressure. The chamber 110 of the present embodiment handles the powdery active material 32A in the internal IN. The chamber 110 is partitioned into a cavity shape by the partition wall 111 and functions as a room that can hold the space of the internal IN in a state depressurized relative to atmospheric pressure. The internal IN of the chamber 110 is depressurized relative to atmospheric pressure by a vacuum pump or the like. The pressure in the internal IN of the chamber 110 may be any value as long as it is depressurized relative to atmospheric pressure. For example, it may be adjusted to a low vacuum environment from atmospheric pressure to 1×10 -1 ~1×10 -2 Pa, or it may be adjusted to a high vacuum environment of 1×10 -6 ~1×10 -7 Pa, or it may be an ultra-high vacuum higher than that, or an extremely high vacuum at the 10 -8 ~10 -9 Pa level. Here, the standard atmospheric pressure is approximately 1013 hPa (approximately 10 5 Pa). The chamber 110 houses the electrode forming portion 100A in this internal IN space.

[0047] Chamber 110 has a carry-in opening 112 formed in the partition wall 111. The carry-in opening 112 is a substantially rectangular slit through which the strip-shaped current collector 31A can be carried in (inserted) from the outside OU to the inside IN of the chamber 110. The carry-in opening 112 penetrates the partition wall 111 along the conveyance direction D1 on the upstream side in the conveyance direction D1, and communicates the outside OU and the inside IN of the chamber 110. Here, the carry-in opening 112 is formed in a size and shape that allows the current collector 31A to be carried in from the outside OU to the inside IN while maintaining the reduced-pressure environment inside the chamber 110. The strip-shaped current collector 31A is continuously supplied and carried into the inside IN through the carry-in opening 112 while being pulled out from a current collector roll 31R provided under normal pressure outside the chamber 110, for example. The current collector 31A carried into the inside IN of the chamber 110 is conveyed along the conveyance direction D1 by a conveyor, conveyance rollers, etc., and is cut at an appropriate timing during the manufacturing process of the electrode 30 to become individual current collectors 31A. Further, a frame body 50 is provided inside the chamber 110 for the current collector 31A carried into the inside IN of the chamber 110. In this case, the frame body 50 may be provided on the current collector 31A, for example, in the inside IN, in front of the active material supply device 120 by a frame body installation device or the like, between the active material supply device 120 and the roll press 130, or behind the roll press 130. FIGS. 2 and 3 illustrate, as an example, the case where the frame body 50 is provided on the current collector 31A in front of the active material supply device 120.

[0048] The active material supply device 120 is a device that supplies powdery active material 32A onto the strip-shaped current collector 31A. The active material supply device 120 is at least partially provided inside the chamber 110 and constitutes the electrode forming portion 100A together with the roll press 130. The active material supply device 120 has at least the supply port 120a (see FIG. 3) and the shutter unit 120b (see FIG. 3) arranged inside the chamber 110 and constitutes the electrode forming portion 100A. When the shutter unit 120b of the active material supply device 120 operates, powdery active material 32A is supplied from the supply port 120a onto the current collector 31A inside the chamber 110.

[0049] The roll press 130 is a device that fixes the active material 32A supplied onto the current collector 31A by the active material supply device 120 to the current collector 31A. The roll press 130 is provided inside the chamber 110 and, as described above, constitutes the electrode forming portion 100A together with a part of the active material supply device 120 (such as the supply port 120a and the shutter unit 120b). For example, in the above-described process, the roll press 130 sandwiches and press-molds the active material 32A placed on the current collector 31A, which has been supplied and conveyed, together with the current collector 31A by a pair of rollers. Thereby, the roll press 130 fixes the active material 32A to the strip-shaped current collector 31A.

[0050] The manufacturing apparatus 100 configured as described above conveys the current collector 31A carried into the interior IN of the chamber 110 through the loading opening 112 to the side of the electrode forming section 100A, and supplies the powdery active material 32A from the supply port 120a of the active material supply device 120 to the conveyed strip-shaped current collector 31A. At this time, the manufacturing apparatus 100 adjusts the opening and closing of the supply port 120a by the shutter unit 120b so that a desired amount of the active material 32A is supplied to the conveyed current collector 31A. Then, the manufacturing apparatus 100 conveys the current collector 31A to which the active material 32A has been supplied to the roll press 130, and presses and forms the active material 32A on the current collector 31A by the roll press 130 to fix the active material 32A to the strip-shaped current collector 31A. Thereafter, the manufacturing apparatus 100 can form the electrode 30 by appropriately cutting the strip-shaped current collector 31A to match the interval of the frame body 50. Note that, as a post-process after the formation of the electrode 30, the manufacturing apparatus 100 may further continuously execute a process of manufacturing the single cell 10 or the battery pack by appropriately laminating the electrodes 30 (that is, the positive electrode 30a and the negative electrode 30b) formed by the above-described process, and the like.

[0051] As described above, the manufacturing apparatus 100 of the present embodiment forms the electrode 30 in a reduced-pressure environment inside the chamber 110. With this configuration, the manufacturing apparatus 100 of the present embodiment can suppress the remaining of air inside the active material 32A after supplying the powdery active material 32A to the current collector 31A, and on top of that, can fix the active material 32A to the current collector 31A. As a result, the manufacturing apparatus 100 can suppress the occurrence of phenomena such as the active material 32A flying off due to the remaining air or the surface of the active material 32A becoming uneven after the pressing by the roll press 130.

[0052] The electrode 30 used in the lithium-ion battery tends to exhibit more stable battery performance when the electrode active material layer 32 containing the active material 32A supplied on the current collector 31A is formed homogeneously. Therefore, as described above, the manufacturing apparatus 100 of the present embodiment can manufacture the electrode 30 that suppresses the inclusion of air in the electrode active material layer 32 and improves the uniformity of the electrode active material layer 32, and thus can manufacture the single cell 10 that can exhibit more stable performance.

[0053] As described above, the overall configuration of the manufacturing apparatus 100 according to the present embodiment has been outlined.

[0054] <Active material recovery structure> With such a configuration, the manufacturing apparatus 100 according to the present embodiment includes a metal foil layer 140, a charging device 141, and an exhaust device 142, as shown in FIGS. 2 and 3, thereby realizing a configuration as an active material processing device that recovers the active material 32A scattered inside the chamber 110 to the inside IN.

[0055] Specifically, the metal foil layer 140 is a film that is provided to be insulated from the inner surface 111a of the partition wall 111 of the chamber 110 and covers the inner surface 111a. The metal foil layer 140 is formed by laminating a conductive metal foil on the inner surface 111a of the chamber 110 with an insulating layer 140a interposed therebetween. The metal foil layer 140 typically covers the entire inner surface 111a. As the material constituting the metal foil layer 140, typically, a metal material that can be charged to substantially the same potential (same polarity) as the fine particles of the active material 32A, for example, one or more metal materials selected from the group consisting of copper, aluminum, nickel, stainless steel, and alloys containing one or more of these metals can be mentioned. The metal foil layer 140 may be formed by attaching a thin plate or a metal foil to the inner surface 111a of the chamber 110, or may be formed by applying the above metal material to the inner surface 111a by methods such as sputtering, electroplating, and coating.

[0056] The charging device 141 is provided inside the chamber 110 (IN), and is a device for charging the particles of the active material 32A in the air inside the chamber 110 (IN) and the metal foil layer 140. As the charging device 141, for example, a known charging gun or the like can be used. The charging device 141 generates high-voltage static electricity and performs corona discharge on the particles of the active material 32A in the air inside the chamber 110 (IN) and the metal foil layer 140, charging the particles of the active material 32A and the metal foil layer 140 to the same polarity. Here, the particles of the active material 32A in the air inside the chamber 110 (IN) include, for example, fine particles of the active material 32A scattered during the formation of the electrode 30 in the electrode forming portion 100A, and also fine particles of the active material 32A that have entered from the outside (OU) of the chamber 110 into the inside (IN) through the loading opening 112.

[0057] In this embodiment, a plurality of charging devices 141 are provided inside the chamber 110 (IN). The charging devices 141 are preferably arranged evenly inside the chamber 110 (IN). Here, one charging device 141 is provided upstream of the active material supply device 120 with respect to the transport direction D1, one is provided between the active material supply device 120 and the roll press 130, and one is provided downstream of the roll press 130, for a total of three. Note that the number of charging devices 141 is not limited to this.

[0058] The particles of the active material 32A in the air and the metal foil layer 140, which are charged to the same polarity by the charging device 141, repel each other. As a result, the particles of the active material 32A do not adhere to the inner surface 111a of the partition wall 111 of the chamber 110 and float in the air inside (IN).

[0059] The exhaust device 142 is a device for exhausting the air inside the chamber 110 (IN). This exhaust device 142 may be, for example, a vacuum pump that reduces the pressure inside the chamber 110 (IN) (that is, it may be used in combination with a vacuum pump), or may be an exhaust device separate from the vacuum pump. Typically, the exhaust device 142 exhausts the fine particles of the active material 32A in the air together with the air inside the chamber 110 (IN) to the outside (OU) of the chamber 110.

[0060] Specifically, the exhaust device 142 has a suction port 142a, an exhaust pipe 142b, and a suction source 142c.

[0061] The suction port 142a is an opening for sucking the air inside the chamber 110. The suction port 142a is formed in the partition wall 111 of the chamber 110 and opens toward the inside IN. Here, the suction port 142a is formed in the partition wall 111 of the chamber 110 at the end face on the most downstream side in the conveyance direction D1, that is, the end face on the side opposite to the side where the carry-in opening 112 is formed. The suction port 142a penetrates the partition wall 111 and communicates the outside OU and the inside IN of the chamber 110.

[0062] The exhaust pipe 142b is a pipe that constitutes an exhaust flow path for exhausting the air sucked from the suction port 142a inside the chamber 110 and the fine particles of the active material 32A to the outside OU of the chamber 110. One end side of the exhaust pipe 142b is connected to the suction port 142a, and the other end side is led out from the chamber 110 and opened to the outside OU.

[0063] The suction source 142c is a device that serves as a source for sucking the air inside IN from the suction port 142a. The suction source 142c is provided on the exhaust pipe 142b outside the chamber 110. The suction source 142c is constituted by, for example, a suction pump or the like. The suction source 142c may typically suck with a negative pressure greater than the negative pressure required to reduce the pressure inside IN of the chamber 110 below atmospheric pressure, or may be used in combination as a suction source for reducing the pressure inside IN of the chamber 110 as described above.

[0064] When the suction source 142c is driven, the exhaust device 142 configured as described above sucks the air inside IN of the chamber 110 from the suction port 142a. At this time, the exhaust device 142 also sucks and collects the fine particles of the active material 32A floating in the air together with the air from the suction port 142a, and exhausts them to the outside OU of the chamber 110 through the exhaust pipe 142b.

[0065] Note that the exhaust device 142 may have a filter device that removes fine particles of the active material 32A from the air on the exhaust pipe 142b and on the upstream side in the exhaust direction from the suction source 142c. In this case, when the exhaust device 142 exhausts the air sucked from the suction port 142a to the outside OU via the exhaust pipe 142b, the fine particles of the active material 32A are removed from the air by the filter device and then exhausted to the outside OU.

[0066] Further, in the manufacturing apparatus 100 of the present embodiment, the carry-in opening 112 for carrying the current collector 31A into the inside IN of the chamber 110 also functions as a suction opening through which air (outside air) can be introduced from the outside OU to the inside IN. The manufacturing apparatus 100 sucks a little air into the inside IN through this carry-in opening 112 by the negative pressure inside the IN while maintaining the reduced-pressure environment inside the chamber 110.

[0067] Furthermore, the manufacturing apparatus 100 of the present embodiment further includes a guide member 143 provided inside the chamber 110 for guiding the flow of the particles of the active material 32A toward the metal foil layer 140 side. Here, the guide member 143 is provided adjacent to the charging device 141. A total of three guide members 143 are provided, one for each of the plurality of charging devices 141. Each guide member 143 is located adjacent to the upstream side in the transport direction D1 with respect to each charging device 141.

[0068] Specifically, the guide member 143 includes an intervening portion 143a and a curved portion 143b, which are integrally formed. The intervening portion 143a is formed in a plate shape along the conveyance direction D1 and intervenes between the current collector 31A conveyed along the conveyance direction D1 and the charging device 141. The curved portion 143b protrudes from the upstream end of the intervening portion 143a in the conveyance direction D1 toward a direction intersecting the conveyance direction D1 and is formed in a curved surface shape that curves toward the metal foil layer 140 side. With this configuration, the guide member 143 restricts the flow of the particles of the active material 32A charged by the charging device 141 from heading toward the charging device 141 and can guide the particles toward the metal foil layer 140 side (typically, the side away from the current collector 31A in the direction intersecting the conveyance direction D1).

[0069] <Method for manufacturing electrode> Next, a method for manufacturing the electrode 30 (method for manufacturing an electrode for a battery) will be described with reference to the flowchart of FIG. 4. The method for manufacturing the electrode 30 described below will be described as being performed by the manufacturing apparatus 100. The method for manufacturing this electrode 30 includes an active material treatment method, and more specifically, includes an electrode formation step (step S1), a charging step (step S2), and an exhaust step (step S3). Here, for easier understanding, each step will be described in sequence, but in actuality, these steps are continuously performed in parallel with each other.

[0070] As an electrode forming process, the manufacturing apparatus 100 forms an electrode 30 by supplying a powdery active material 32A onto a current collector 31A in an electrode forming unit 100A inside the chamber 110 (step S1). Here, the manufacturing apparatus 100 supplies a desired amount of the active material 32A to the current collector 31A by means of a shutter unit 120b, and fixes the active material 32A onto the current collector 31A by means of a roll press 130 to form the electrode 30. The manufacturing apparatus 100 performs the above processing on the current collector 31A carried into the inside IN of the chamber 110 through the carry-in opening 112, and sequentially forms the electrodes 30. During this period, the manufacturing apparatus 100 sucks in air to such an extent that a reduced-pressure environment can be maintained inside the chamber 110 through the carry-in opening 112 by the negative pressure inside the chamber 110 of the chamber 110.

[0071] During this period, as a charging process, the manufacturing apparatus 100 charges the particles of the active material 32A in the air inside the chamber 110 and a metal foil layer 140 which is provided to be insulated from and covers the inner surface 111a of the chamber 110 by means of a charging device 141 (step S2). Here, the manufacturing apparatus 100 performs corona discharge on the fine particles of the active material 32A scattered along with the formation of the electrode 30 in the electrode forming unit 100A and the fine particles of the active material 32A that have entered the inside IN of the chamber 110 through the carry-in opening 112 by means of the charging device 141, and charges the particles of these active materials 32A and the metal foil layer 140 to the same polarity. As a result, the particles of the active material 32A in the air inside the IN do not adhere to the inner surface 111a of the partition wall 111 of the chamber 110 and float in the air inside the IN.

[0072] Then, as an exhaust process, the manufacturing apparatus 100 exhausts the air inside the chamber 110 by means of an exhaust device 142 (step S3). At this time, the manufacturing apparatus 100 also sucks and collects the fine particles of the active material 32A that have become suspended in the air inside the IN due to being charged by the charging device 141 together with the air, and exhausts them to the outside OU of the chamber 110 through an exhaust pipe 142b from a suction port 142a.

[0073] <Operational effects of the embodiment> The manufacturing apparatus 100, manufacturing method, and active material treatment method described above can charge the particles of the active material 32A in the air inside the chamber 110 (IN) and the metal foil layer 140 covering the inner surface 111a of the chamber 110 to the same polarity by the charging device 141. Thereby, the manufacturing apparatus 100 can repel the particles of the active material 32A handled inside the chamber 110 (IN) and the metal foil layer 140 from each other, so that it is possible to suppress the particles of the active material 32A from adhering to the inner surface 111a of the chamber 110. Then, the manufacturing apparatus 100 can exhaust and collect the particles of the active material 32A floating in the air inside the chamber 110 (IN) together with the air to the outside (OU) by the exhaust device 142 without adhering to the inner surface 111a of the chamber 110. As a result, the manufacturing apparatus 100, manufacturing method, and active material treatment method can appropriately recover the active material 32A scattered inside the chamber 110 (IN).

[0074] Thereby, the manufacturing apparatus 100 does not need to stop the manufacturing apparatus 100, for example, to clean the inner surface 111a of the chamber 110, and can recover the active material 32A scattered inside (IN) while the manufacturing apparatus 100 is in operation, so that the manufacturing efficiency of the electrode 30 can be improved.

[0075] Further, the manufacturing apparatus 100, manufacturing method, and active material treatment method described above are provided with a carry-in opening 112 through which the inside of the chamber 110 (IN) is depressurized from the atmospheric pressure and air can be introduced from the outside (OU) into the inside (IN). With this configuration, the manufacturing apparatus 100 can take in the air used when recovering the active material 32A from the carry-in opening 112 into the inside (IN) by utilizing the negative pressure inside the chamber 110 (IN). As a result, the manufacturing apparatus 100, manufacturing method, and active material treatment method can recover the active material 32A in the air by utilizing the air effectively taken into the inside (IN) through the carry-in opening 112.

[0076] Here, the manufacturing apparatus 100, manufacturing method, and active material processing method described above can suck and collect the fine particles of the active material 32A scattered in the air inside the chamber 110 into the outside OU together with the air when manufacturing the electrode 30 by the electrode forming unit 100A inside the chamber 110. As a result, even if the fine particles of the active material 32A scatter in the air inside the chamber 110 and contaminate the space inside the chamber 110 when forming the electrode 30 inside the chamber 110 of the manufacturing apparatus 100, the cleanliness of the inside of the chamber 110 can be appropriately ensured. As a result, the manufacturing apparatus 100, manufacturing method, and active material processing method can manufacture the electrode 30 in an environment where the cleanliness is appropriately ensured, and thus, for example, the electrode 30 with desired performance can be manufactured with high precision.

[0077] Furthermore, the manufacturing apparatus 100, manufacturing method, and active material processing method described above can guide the flow of the particles of the active material 32A charged by the charging device 141 toward the metal foil layer 140 side by the guide member 143 while preventing the particles of the active material 32A from continuing to stay near the charging device 141. Then, the manufacturing apparatus 100 can make it easier for the exhaust device 142 to exhaust the particles of the active material 32A guided toward the metal foil layer 140 while floating them in the air without adhering them to the inner surface 111a. As a result, the manufacturing apparatus 100, manufacturing method, and active material processing method can more efficiently collect the active material 32A scattered inside the chamber 110.

[0078] <Modification example> Note that the active material processing apparatus, battery electrode manufacturing apparatus, active material processing method, and battery electrode manufacturing method according to the above-described embodiment of the present invention are not limited to the above-described embodiment, and various modifications are possible within the scope described in the claims.

[0079] In the above description, the electrode forming unit 100A has been described as directly supplying the powdery active material 32A onto one surface of the current collector 31A as the base film to form the electrode 30, but it is not limited thereto. For example, the electrode forming unit 100A may supply the active material 32A onto a transfer film, which is a base film different from the current collector 31A, and after fixing it once, transfer and fix the active material 32A formed into a powder shape on the transfer film onto one surface of the current collector 31A to form the electrode 30. In this case, the electrode forming unit 100A may be configured to include a transfer unit for transferring the active material 32A from the transfer film to the current collector 31A. Further, the base film may be the separator 40. That is, as the base film, the current collector 31A, the separator 40, or the transfer film can be used. When the base film is, for example, the transfer film, a lithium-ion battery electrode can be obtained by transferring, for example, the active material layer (electrode composition layer) formed on the film onto the current collector as described above.

[0080] In the above description, the frame body 50 has been described as being provided on the current collector 31A inside the chamber 110 in the interior IN, but it is not limited to this, and it may be configured to be provided outside in the exterior OU. For example, the frame body 50 may be provided on the current collector 31A in front of the carry-in opening 112 by a frame body installation device or the like in the exterior OU. In this case, the strip-shaped current collector 31A is carried into the interior IN from the carry-in opening 112 with the frame body 50 attached in front of the carry-in opening 112. Also in this case, the carry-in opening 112 may be formed in a size and shape that allows the frame body 50 to be carried into the interior IN together with the current collector 31A from the exterior OU while maintaining the reduced-pressure environment inside the interior IN of the chamber 110. Further, the frame body 50 may be provided on the current collector 31A, for example, by a frame body installation device or the like, at the subsequent stage of the roll press 130 and outside the chamber 110 in the exterior OU. Also, the active material processing device, the battery electrode manufacturing device, the active material processing method, or the battery electrode manufacturing method according to the present embodiment may not include a frame body installation device or a frame body installation step. For example, when a transfer film is used instead of the current collector 31A, after the electrode composition layer (electrode active material layer 32) is formed on the transfer film (that is, after the electrode formation step), the frame body 50 may be disposed on the current collector 31A onto which the electrode composition layer has been transferred, or on the current collector 31A before the electrode composition layer is transferred.

[0081] Also, in the above description, the strip-shaped current collector 31A has been described as being carried into the interior IN through the carry-in opening 112 while being pulled out from the current collector roll 31R provided under normal pressure in the exterior OU of the chamber 110, but it is not limited to this, and it may be pulled out from the current collector roll 31R provided under reduced pressure in the interior IN of the chamber 110. Also, the entire active material supply device 120 may be provided inside the interior IN of the chamber 110.

[0082] Also, in the above description, the manufacturing apparatus 100 has been described as also functioning as a suction opening through which air (outside air) can be introduced from the exterior OU to the interior IN at the carry-in opening 112, but it is not limited to this. The suction opening of the chamber 110 may be provided separately from the carry-in opening 112.

[0083] In the above description, the manufacturing apparatus 100 has been described as including the guide member 143, but it may be configured without the guide member 143.

[0084] In the above description, the chamber 110 has been described as having its internal IN depressurized below atmospheric pressure, but it is not limited to this.

[0085] In the above description, the charging device 141 has been described as being provided in a plurality (here, three) in the arrangement illustrated in FIGS. 2 and 3, but it is not limited to this. For example, the charging device 141 may be one as long as it can cover the entire space of the internal IN of the chamber 110. Further, even when a plurality of charging devices 141 are provided in the internal IN of the chamber 110, for example, it is not limited to the form in which both the particles of the active material 32A and the metal foil layer 140 are charged by one charging device 141. For example, the charging device 141 zones the internal IN of the chamber 110 into a region for charging the particles of the active material 32A, a region for charging the metal foil layer 140 (in other words, a region near the inner surface 111a for electrostatically collecting the charged particles of the active material 32A), etc., and may be individually provided in each region. And in this case, each charging device 141 may be controlled individually according to the state of each region so that the particles of the active material 32A and the metal foil layer 140 are charged to the same polarity (preferably the same potential and the same charge). Further, in some cases, the manufacturing apparatus 100 may be provided with a dust collection route forming plate inside the internal IN that is charged to the same polarity (preferably the same potential and the same charge) as the particles of the active material 32A and the metal foil layer 140 and controls the dust collection route, in addition to the above-described guide member 143.

[0086] In the above description, the active material processing apparatus has been described as being applied to the manufacturing apparatus (for a battery electrode manufacturing apparatus) 100 in which the electrode forming unit 100A is housed in the internal IN of the chamber 110, but it is not limited to this, and it may be applied to other apparatuses that handle the powdery active material 32A in the internal IN of the chamber 110 without including the electrode forming unit 100A.

[0087] The active material processing apparatus, battery electrode manufacturing apparatus, active material processing method, and battery electrode manufacturing method according to this embodiment may be configured by appropriately combining the components of the above-described embodiments and modification examples.

Description of Reference Numerals

[0088] 10 single cell 30 electrode 31A current collector (base film) 32A active material 40 separator 50 frame 100 manufacturing apparatus (battery electrode manufacturing apparatus, active material processing apparatus) 100A electrode forming section 110 chamber 111 partition wall 111a inner surface 112 carry-in opening (suction opening) 120 active material supply device 130 roll press 140 metal foil layer 140a insulating layer 141 charging device 142 exhaust device 142a suction port 142b exhaust pipe 142c suction source 143 guide member 143a intervening portion 143b curved portion D1 conveyance direction IN inside OU outside

Claims

1. A chamber for handling powdery active material therein, a metal foil layer provided insulated from the inner surface of the chamber and covering the inner surface, a charging device provided inside the chamber for charging particles of the active material and the metal foil layer in the air inside the chamber to the same polarity, and an exhaust device for exhausting the air inside the chamber. An active material processing apparatus.

2. The chamber has a reduced pressure inside compared to atmospheric pressure and has an intake opening through which air can be introduced from the outside to the inside. The active material processing apparatus according to Claim 1.

3. An electrode forming part provided inside the chamber for forming an electrode by supplying the powdery active material onto a base film. The active material processing apparatus according to Claim 1 or Claim 2.

4. A guide member provided inside the chamber for guiding the flow of particles of the active material toward the metal foil layer side. The active material processing apparatus according to any one of Claims 1 to 3.

5. A chamber with a reduced pressure inside compared to atmospheric pressure, an electrode forming part provided inside the chamber for forming an electrode by supplying powdery active material onto a base film, a metal foil layer provided insulated from the inner surface of the chamber and covering the inner surface, a charging device provided inside the chamber for charging particles of the active material and the metal foil layer in the air inside the chamber to the same polarity, and an exhaust device for exhausting the air inside the chamber. An apparatus for manufacturing an electrode for a battery.

6. A charging step of charging particles of the active material in the air inside a chamber for handling powdery active material therein and a metal foil layer provided insulated from the inner surface of the chamber and covering the inner surface to the same polarity, and an exhaust step of exhausting the air inside the chamber. An active material processing method.

7. An electrode forming step of forming an electrode by supplying powdery active material onto a base film inside a chamber with a reduced pressure inside compared to atmospheric pressure, a charging step of charging particles of the active material in the air inside the chamber and a metal foil layer provided insulated from the inner surface of the chamber and covering the inner surface to the same polarity inside the chamber, and an exhaust step of exhausting the air inside the chamber. A method for manufacturing an electrode for a battery.

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