JPWO2017110797A1 - Electrode material manufacturing system, and electrode material, electrode, battery and capacitor manufacturing method - Google Patents

Abstract

The electrode material manufacturing system includes a storage container that stores at least one of an active material and a solvent, and a raw material processing unit that divides at least a part of a raw material containing an alkali metal and supplies the raw material into the storage container.

Description

Cross-reference of related applications

  This international application claims priority based on Japanese Patent Application No. 2015-250193 filed with the Japan Patent Office on December 22, 2015, and is based on Japanese Patent Application No. 2015-250193. The entire contents are incorporated by reference into this international application.

  The present disclosure relates to an electrode material manufacturing system and an electrode material, electrode, battery, and capacitor manufacturing method.

2. Description of the Related Art In recent years, electronic devices have been remarkably reduced in size and weight, and accordingly, there has been an increasing demand for downsizing and weight reduction of batteries used as power sources for driving the electronic devices.
In order to satisfy such demands for miniaturization and weight reduction, non-aqueous electrolyte secondary batteries represented by lithium ion secondary batteries have been developed. Moreover, a lithium ion capacitor is known as an electricity storage device corresponding to an application that requires high energy density characteristics and high output characteristics. Further, sodium ion type batteries and capacitors using sodium which is cheaper than lithium and resource-rich are also known.

  In such batteries and capacitors, a process (generally referred to as pre-doping) in which an alkali metal is previously doped into an electrode active material is employed for various purposes. For example, in a lithium ion capacitor, lithium pre-doping is performed for the purpose of lowering the negative electrode potential and increasing the energy density. In this case, a method of pre-doping the negative electrode active material in the cell using a current collector having a through hole has become the mainstream (see, for example, Patent Document 1).

  Moreover, in a lithium ion secondary battery, pre dope is performed for the purpose of reducing the irreversible capacity | capacitance of a negative electrode. In this case, in addition to the above method, a method of pre-doping the negative electrode active material before assembling the battery is employed (see, for example, Patent Documents 2 and 3). Furthermore, when producing a sodium ion type power storage device, a method of pre-doping sodium into the negative electrode before assembling the power storage device is employed (Patent Document 4).

  Moreover, in patent document 5, in order to suppress decomposition | disassembly of the electrolyte solution on the negative electrode at the time of the initial charge of a secondary battery, the fibrous carbon material used as a negative electrode is made to contact n-butyl lithium in a nonaqueous solvent. It has been proposed to store lithium ions in the fibrous carbon material.

However, the conventional methods listed above have been difficult to put into practical use from the viewpoint of manufacturing cost and simplicity.
On the other hand, in Patent Documents 6 and 7, as a method of pre-doping lithium in a short time and easily, a lithium-dopeable material and finely cut lithium metal or granular lithium metal are kneaded and mixed in the presence of a solvent. Thus, a method for pre-doping has been proposed.

  In Patent Document 8, a paste obtained by kneading a carbon material and fine particles of lithium coated with a polymer is applied onto a current collector, and the paste is dried to produce a negative electrode. It is disclosed that a lithium ion is occluded in a carbon material to produce an electrochemical capacitor.

JP 2007-67105 A JP 7-235330 A Japanese Patent Laid-Open No. 9-293499 JP 2012-69894 A JP 2000-156222 A JP 2012-38686 A JP 2012-74189 A JP 2007-324271 A

  However, finely cut lithium metal and granular lithium metal are liable to stick to each other and are very difficult to handle. In addition, when finely cut or granulated, the specific surface area of the lithium metal increases, which increases the risk.

  Such a problem can be improved to some extent by coating the surface of lithium metal with a polymer or the like, but since there is a similar problem when coating lithium metal with a polymer or the like, the essential problem has not been solved. Is in the situation. Moreover, there is also a problem that the manufacturing cost becomes very high by treating lithium metal with a polymer or the like.

  One aspect of the present disclosure provides an electrode material manufacturing system and an electrode material, electrode, battery, and capacitor manufacturing method capable of safely and inexpensively manufacturing an electrode material pre-doped with an alkali metal. Is preferred.

  One aspect of the present disclosure is an electrode material including: a storage container that stores at least one of an active material and a solvent; and a raw material processing unit that divides at least a part of a raw material containing an alkali metal and supplies the raw material into the storage container. It is a manufacturing system. If this manufacturing system is used, an electrode material pre-doped with an alkali metal can be manufactured at low cost and safely.

It is side sectional drawing showing the structure of the manufacturing system of an electrode material. It is a top view showing the structure of a die | dye and a cutter. It is a top view showing the structure of a die | dye and a cutter. It is side sectional drawing showing the structure of the manufacturing system of an electrode material.

DESCRIPTION OF SYMBOLS 1,101 ... Manufacturing system of electrode material 3, 103 ... Raw material preparation / processing unit, 5 ... Storage container, 5A ... Opening part, 6 ... Mixing unit, 7 ... Container, 7A ... Insertion hole, 7B ... Vent hole, 9 ... Piston, 11 ... Die, 11A ... Die hole, 13 ... Cutter, 15 ... Exhaust pipe, 17 ... Ingot, 19 ... Pressing part, 21 ... Shaft part, 23 ... Shaft, 24 ... Rotary blade, 25 ... Electrolyte, 27 ... active material, 29 ... raw material in the form of a wire, 31 ... divided raw material, 33 ... slit, 34 ... housing, 34A ... introduction slit, 34B ... outlet slit, 35, 37 ... work rolls, 39, 41, 43, 45 ... support rolls, 47, 49 ... movable base, 51, 53 ... guide rolls, 55 ... plate-like raw materials, 57 ... raw materials having sheet form, 59 ... divided raw materials

1. Electrode Material Manufacturing System (A) Raw Material Processing Unit The raw material processing unit divides at least part of the raw material containing alkali metal and supplies the divided raw material into the storage container. Examples of the alkali metal include lithium and sodium.

  The form of the raw material before being divided is not particularly limited, and examples thereof include forms such as a sheet, a wire, a rod, and a melt. The sheet or wire form is preferable because the division process becomes easy.

  The electrode material manufacturing system of the present disclosure may include a supply unit that supplies the raw material to the raw material processing unit. The form of the raw material supplied by the supply unit is not particularly limited, and examples include forms such as a sheet, a wire, a rod, and a melt, but a sheet or a wire is preferable. The supply unit can draw the sheet or wire from a reel on which the sheet or wire has been wound in advance and supply the sheet or wire to the raw material processing unit.

  The width of the sheet is preferably in the range of 2 mm to 10 cm. The thickness of the sheet is preferably in the range of 10 μm to 1 cm. The diameter of the wire is preferably in the range of 1 mm to 2 cm. The width and thickness of the sheet and the diameter of the wire can be appropriately set according to the amount of the active material to be doped, but when it is within the above range, it is excellent in terms of doping efficiency.

  The length of the wire divided and supplied to the storage container is preferably in the range of 2 mm to 10 cm. The length of the sheet divided and supplied to the storage container is preferably in the range of 2 mm to 10 cm. The lengths of the divided sheets and wires can be appropriately set according to the amount of the active material to be doped. However, when the length is within the above range, the division efficiency and the doping efficiency are excellent.

  The raw material may consist essentially of an alkali metal, or may contain other components in addition to the alkali metal. Examples of raw materials include alkali metal alloys, laminates of alkali metal sheets and other metal (for example, copper) sheets, alkali metal sheets and resins (for example, polyethylene, polypropylene, PET, polyvinyl chloride, poly And a laminate with a sheet made of vinylidene chloride).

  Divided pieces generated by dividing the raw material processing unit are smaller than the raw material before division. The dividing method is not particularly limited, but from the viewpoint of productivity and manufacturing cost, the raw material processing unit is preferably divided by, for example, cutting the raw material with a cutting unit.

  The cutting unit is not particularly limited, and examples include those using a cutting blade and those using a heat source for fusing such as laser or plasma, but those using a cutting blade are preferable from the viewpoint of manufacturing cost. . The material constituting the cutting blade is not particularly limited, and examples thereof include metals, ceramics, resins, and the like, but resins are preferable from the viewpoint of difficulty in adhering alkali metals.

  As the kind of resin, polyethylene, polypropylene, and polyacetal are preferable. Specific embodiments of a cutting unit using a cutting blade are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 59-173955 and 7-136978.

The length of the raw material after cutting is preferably in the range of 2 mm to 10 cm. When it is within this range, the cutting efficiency and the doping efficiency are excellent.
The raw material processing unit may divide the alkali metal by dispersing the molten alkali metal in a dispersion medium and generating a granular dispersion. The molten alkali metal corresponds to the raw material before division. The granular dispersion and the alkali metal particles on which it solidifies correspond to the raw material after the division. The diameter of the granular dispersion is preferably in the range of 10 μm to 1 cm. When it is within this range, it is excellent in terms of doping efficiency.

  The raw material processing unit in this case preferably includes, for example, a container that contains at least molten alkali metal and a dispersion medium, a stirring unit that stirs the inside of the container, and a heating unit that heats the container. The molten alkali metal may be an alkali metal heated and melted before being added to the dispersion medium, or an alkali metal melted in a dispersion medium heated to a temperature equal to or higher than the melting point of the alkali metal. Also good.

  As the dispersion medium, a hydrocarbon oil having a flash point of 90 ° C. or higher is preferable. After the alkali metal is made into a granular dispersion, for example, the dispersion can be cooled, the dispersion medium can be removed by filtration, the alkali metal particles can be washed with a hydrocarbon solvent, and the alkali metal particles can be dried. In this case, the raw material processing unit may further include a cooling unit, a filtration unit, a unit that supplies a hydrocarbon solvent, a drying unit, and the like. Specific embodiments of an apparatus for dispersing molten alkali metal to obtain alkali metal particles are disclosed in, for example, the examples of JP-T-2010-535936.

(B) Storage container A storage container accommodates at least one of an active material and a solvent. Moreover, the raw material divided | segmented by the raw material processing unit is supplied in a storage container. Therefore, the storage container can store an aggregate including at least the divided raw material and at least one of the active material and the solvent. This assembly can be used, for example, for producing a dispersion in which an electrode material, a precursor thereof, and divided raw materials are dispersed in a solvent.

  Examples of the electrode material include an electrode-forming slurry containing an alkali metal, an active material and a solvent, and an active material doped with an alkali metal. Moreover, as a precursor of an electrode material, it is a mixture containing the divided raw material and an active material, for example, in a state before the active material is doped with an alkali metal. In addition, the dispersion in which the divided raw materials are dispersed in a solvent is obtained by dispersing the divided raw materials in a solvent in the absence of an active material.

  The size and shape of the storage container can be appropriately set according to the method of processing performed in the storage container, the amount of substance to be processed, and the like. Moreover, the material which comprises a storage container can also be suitably selected from a metal, glass, ceramics, resin, etc. according to the method of the process performed in this storage container.

  The storage container can store the active material. The active material to be accommodated is not particularly limited as long as it is an electrode active material applicable to a battery or a capacitor using insertion / extraction of alkali metal ions, and may be a negative electrode active material or a positive electrode It may be an active material.

  The type of the negative electrode active material is not particularly limited. For example, graphite, graphitizable carbon, non-graphitizable carbon, carbon materials such as composite carbon materials in which graphite particles are coated with a carbide of pitch or resin; lithium and Examples thereof include metals or metalloids such as Si and Sn that can be alloyed or materials containing these oxides. Specific examples of the carbon material include carbon materials described in JP2013-258392A. Specific examples of the metal or metalloid capable of being alloyed with lithium or a material containing these oxides include materials described in JP-A-2005-123175 and JP-A-2006-107795.

Examples of the positive electrode active material include transition metal oxides such as manganese oxide and vanadium oxide; sulfur-based active materials such as sulfur alone and metal sulfides.
Both the positive electrode active material and the negative electrode active material may be composed of a single material or a mixture of two or more materials. The electrode material manufacturing system according to the present disclosure is suitable for the treatment of a negative electrode active material, and is particularly suitable when the negative electrode active material is a carbon material or a material containing Si or an oxide thereof.

  In general, when a carbon material is used as the active material, an energy storage device with low internal resistance is obtained when the particle size of the carbon material is reduced, while an irreversible capacity increases, which occurs when the electricity storage device is held in a charged state. Problems such as an increase in the amount of gas to be generated occur. Also, when using a material containing Si or its oxide as an active material, the irreversible capacity generally tends to increase. By using the electrode material manufacturing system of the present disclosure, it is possible to uniformly disperse the refined alkali metal in the active material particles. Therefore, a carbon material having a small particle diameter or Si or an oxide thereof is used as the active material. Such a problem can be suppressed even in the case of using a material containing the same.

  The storage container can store the solvent. When producing an active material doped with an alkali metal using the electrode material production system of the present disclosure, the solvent is not particularly limited as long as it is a solvent having alkali metal ion conductivity, but is an organic solvent. Are preferred, and aprotic organic solvents are particularly preferred. It is preferable that an alkali metal salt is dissolved in the solvent. Examples of the alkali metal salt include a known lithium salt or sodium salt used as an electrolyte. In the solvent, a known additive added to the electrolytic solution may be further dissolved.

  Moreover, when manufacturing the slurry for electrode formation containing an alkali metal and an active material using the manufacturing system of the electrode material of this indication, a storage container is a slurry for electrode formation, such as a binder, a thickener other than the said solvent. It may further contain a known component that constitutes. In addition to the above-described components, the storage container may further store a conductive additive.

  For example, the storage container may include an opening on the upper side thereof. And a raw material processing unit can be arrange | positioned above an opening part. In that case, it becomes easier to supply the raw material divided | segmented by the raw material processing unit in a storage container.

  The raw material processing unit may be arranged on the bottom surface of the storage container. When the raw material processing unit is arranged on the bottom surface, if the specific gravity of the raw material is small, the raw material can be divided (for example, cut) while supplying the raw material upward from the bottom surface of the storage container. Therefore, the raw material can be divided more easily.

(C) Raw Material Production Unit The electrode material manufacturing system of the present disclosure may further include a raw material production unit that produces a raw material having a sheet or wire form by extrusion or rolling.

  An example of a production system of an electrode material provided with a raw material creation unit for creating a raw material having a wire form by extrusion will be described with reference to FIGS. The electrode material manufacturing system 1 includes a raw material preparation / processing unit 3, a storage container 5, and a mixing unit 6.

  The raw material creation / processing unit 3 includes a container 7, a piston 9, a die 11, a cutter 13, and an exhaust pipe 15. The raw material preparation / processing unit 3 corresponds to a raw material processing unit and a raw material preparation unit.

  The container 7 is a hollow cylindrical container having an open bottom. The axial direction of the cylinder is the vertical direction. The container 7 can store an ingot 17 of a raw material (for example, alkali metal) therein. The piston 9 includes a disk-shaped pressing portion 19 and a shaft portion 21. The pressing part 19 is accommodated in the ingot 17. The side surface of the pressing portion 19 is in contact with the inner surface of the container 7. The shaft portion 21 is inserted through an insertion hole 7 </ b> A provided in the upper portion of the container 7. The lower end of the shaft portion 21 is connected to the pressing portion 19, and the opposite end portion is connected to a drive mechanism (not shown) outside the container 7. The piston 9 moves up and down by the driving force transmitted from the driving mechanism.

  The die 11 is a disk-shaped member provided with a plurality of die holes 11A. The die hole 11A is a circular hole. The die 11 is attached to the container 7 so as to close the opening below the container 7. The cutter 13 is a resin cutter attached to the bottom surface of the die 11. The cutter 13 and the lower surface of the die 11 are in contact with each other. The cutter 13 is rotatably attached to a shaft 23 located near the center of the die 11. The cutter 13 rotates about the shaft 23 by a driving force transmitted from a driving mechanism (not shown). When the cutter 13 rotates, the range in which the cutter 13 operates includes all the die holes 11A.

The exhaust pipe 15 is connected to a vent hole 7B provided on the side surface of the container 7 at one end thereof. The exhaust pipe 15 is connected to a vacuum pump (not shown) at the opposite end.
The storage container 5 includes an opening 5A on the upper side, and the raw material preparation / processing unit 3 is attached to the opening 5A. The die 11 and the cutter 13 are located inside the storage container 5. An electrolytic solution supply pipe 22 is connected to the upper portion of the side surface of the storage container 5. The electrolyte solution 25 can be supplied from the electrolyte solution supply pipe 22 into the storage container 5.

  The mixing unit 6 includes a rotating blade 24 in the vicinity of the bottom surface in the storage container 5. The mixing unit 6 can stir and mix the contents in the storage container 5 by rotating the rotary blade 24.

  When using the electrode material manufacturing system 1, the electrolytic solution 25 is put into the storage container 5 through the electrolytic solution supply pipe 22. The amount of the electrolytic solution 25 is set so that the bottom surface of the die 11 is immersed in the electrolytic solution 25. In addition, an active material 27 such as carbon is placed in the storage container 5. A raw material ingot 17 is placed inside the container 7. The ingot 17 is sandwiched from above and below by the die 11 and the piston 9. In addition, the inside of the container 7 is evacuated through the exhaust pipe 15.

  Next, the piston 9 is pushed down. At this time, the raw material 29 in the form of a wire is extruded from the die hole 11A. Since the electrolytic solution 25 exists below the die 11, the raw material 29 having a wire form is extruded into the electrolytic solution 25. By dividing the raw material 29 having a wire shape by rotating the cutter 13 at a constant cycle, a divided raw material 31 is generated. The divided raw material 31 has the form of a short wire and is supplied into the storage container 5.

  Next, an example of an electrode material manufacturing system provided with a raw material creation unit for creating a raw material having a sheet form by extrusion will be described with reference to FIG. This electrode material manufacturing system basically has the same configuration as that of the electrode material manufacturing system 1, but the die 11 is not a circular die hole but an elongated slit 33 as shown in FIG. A plurality. When the piston 9 is pushed down, a raw material having a sheet form is extruded from each slit 33. By dividing the raw material having a sheet form by rotating the cutter 13 at a constant period, a divided raw material is generated. The divided raw materials have a rectangular sheet form and are supplied into the storage container 5.

  Next, an example of an electrode material manufacturing system including a raw material creation unit that creates a raw material having a sheet form by rolling will be described with reference to FIG. The electrode material manufacturing system 101 includes a raw material creation / processing unit 103, a storage container 5, and a mixing unit 6.

  The raw material creation / processing unit 103 includes a housing 34, work rolls 35 and 37, support rolls 39, 41, 43 and 45, movable stands 47 and 49, and guide rolls 51 and 53. The raw material creation / processing unit 103 corresponds to a raw material processing unit and a raw material creation unit.

  The housing 34 is a hollow box-shaped container. The top plate is provided with an introduction slit 34A, and the bottom plate is provided with a lead-out slit 34B. The housing 34 accommodates work rolls 35 and 37, support rolls 39, 41, 43, and 45, movable bases 47 and 49, and guide rolls 51 and 53.

  The work rolls 35 and 37 are opposed to each other at a constant interval. The axis of the work roll 35 and the axis of the work roll 37 are parallel and at the same height. The gap between the work roll 35 and the work roll 37 is directly below the introduction slit 34A and above the lead-out slit 34B. The work roll 35 is supported by support rolls 39 and 41. The work roll 37 is supported by support rolls 43 and 45.

  The movable table 47 supports the support rolls 39 and 41 in a rotatable manner. The movable base 47 can adjust the position in the left-right direction in FIG. The movable base 49 supports the support rolls 43 and 45 in a rotatable manner. The movable table 49 is urged in the direction A shown in FIG. 4 by an urging mechanism (not shown).

  The guide rolls 51 and 53 are located in the vicinity of the lead-out slit 34B. The guide rolls 51 and 53 are opposed to each other with a certain interval. The axis of the guide roll 51 and the axis of the guide roll 53 are parallel and at the same height.

  The storage container 5 is provided with an opening 5A on the upper side, and a raw material preparation / treatment unit 103 is attached to the opening 5A. A part of the lower side of the housing 34 is located inside the storage container 5. An electrolytic solution supply pipe 22 is connected to the upper portion of the side surface of the storage container 5. The electrolyte solution 25 can be supplied from the electrolyte solution supply pipe 22 into the storage container 5.

  The mixing unit 6 includes a rotating blade 24 in the vicinity of the bottom surface in the storage container 5. The mixing unit 6 can stir and mix the contents in the storage container 5 by rotating the rotary blade 24.

  When the electrode material manufacturing system 101 is used, the electrolytic solution 25 is put into the storage container 5 through the electrolytic solution supply pipe 22. The amount of the electrolytic solution 25 is set so that the bottom surface of the housing 34 is immersed in the electrolytic solution 25. In addition, an active material 27 such as carbon is placed in the storage container 5.

  Next, the plate-shaped raw material 55 is introduced into the housing 34 from the introduction slit 34 </ b> A. The plate-shaped raw material 55 is sent downward and pushed between the work rolls 35 and 37. At that time, the work rolls 35 and 37 rotate in the direction B in FIG. 4 while pressing the plate-shaped raw material 55. The plate-shaped raw material 55 is subjected to a rolling process by the work rolls 35 and 37 to become a raw material 57 having a sheet form. The thickness of the raw material 57 having a sheet form is smaller than the thickness of the plate-shaped raw material 55.

  The raw material 57 in the form of a sheet is guided by the guide rolls 51 and 53, passes through the lead-out slit 34 </ b> B, and is led out below the housing 34. Since the electrolytic solution 25 exists below the casing 34, the raw material 57 having a sheet form is led into the electrolytic solution 25. By dividing the raw material 57 having a sheet form by rotating the cutter 13 at a constant cycle, a divided raw material 59 is generated. The divided raw material 59 has a rectangular sheet form and is supplied into the storage container 5.

In addition, the raw material preparation unit may be integrated with the raw material processing unit as in the above example, or may be a separate body.
(D) Mixing unit The electrode material manufacturing system according to the present disclosure is a mixture for mixing an aggregate containing a divided raw material and at least one of an active material and a solvent, which is stored in the storage container of (B). A unit may be further provided.

  By the mixing unit, for example, an aggregate including the divided raw material and active material can be mixed. In this case, since the divided raw material can be uniformly dispersed in the active material, it becomes possible to uniformly dope the entire active material with the alkali metal in the subsequent steps.

  Moreover, the assembly containing an active material, the divided | segmented raw material, and a solvent can be mixed with a mixing unit, for example. In this case, the active material and the alkali metal can be brought into contact with each other, so that the alkali metal can be doped into the active material.

  Moreover, the aggregate | assembly containing the divided raw material, active material, binder, organic solvent etc. can be mixed with a mixing unit, for example. In this case, it becomes possible to manufacture the slurry for electrode formation.

  The mixing unit is not particularly limited as long as it can mix the aggregate uniformly, and may be, for example, a unit that rotates, vibrates, or swings the storage container itself of (B), A stirrer, an ultrasonic vibrator, or the like that stirs and mixes the contents of the storage container (B) may be used, or a combination of both.

  The storage container (B) and the mixing unit may be integrated. Examples of the apparatus in which the storage container and the mixing unit of (B) are integrated include a known rotating mixer, a rotating / revolving mixer, a pressure kneader, and the like. The mixing unit may be a separate body from the storage container (B). Examples of the mixing unit that is separate from the storage container (B) include a known uniaxial stirrer and a magnetic stirrer.

(E) Mixing container The electrode material manufacturing system of the present disclosure may further include a mixing container for mixing the divided raw material, active material, and solvent. The mixing container includes a mixing unit similar to the mixing unit (D).

  For example, in the storage container (B), the divided raw materials can be dispersed in a solvent, and then the obtained dispersion and the active material or the slurry containing the active material can be mixed in the mixing container. . In this case, the alkali metal contained in the raw material can be more uniformly dispersed.

Further, in the mixing container, the active material and the alkali metal can be brought into contact with each other in the presence of a solvent, and the alkali metal can be doped into the active material.
(F) Pressurization unit The electrode material manufacturing system of the present disclosure further includes a pressurization unit that statically pressurizes an assembly including divided raw materials and an active material, preferably in the presence of a solvent. Also good. The pressurization means applying a pressure larger than normal pressure. Further, the “statically pressurizing” means pressurizing an assembly that has been left still (that is, substantially not subjected to the mixing treatment). When the aggregate containing the active material is pressurized, the contact resistance between the active material particles can be reduced, so that the entire active material contained in the aggregate can be quickly and uniformly doped with alkali metal. In addition, in a statically pressurized state, the active material particles and the alkali metal hardly collide violently, so that the safety is further enhanced.

  The pressurization by the pressurizing unit may be performed within the storage container (B) or may be performed outside the storage container (B). When pressurization by the pressurizing unit is performed in the storage container of (B), as the pressurization unit, for example, an assembly stored in the storage container of (B) is an inner surface of the storage container of (B). And a pressing unit that presses in the direction.

  The form of the pressing unit is not particularly limited as long as it can press the aggregate, and can be, for example, a plate shape, a rod shape, a spherical shape, or the like. It is preferable that the pressing unit has a plurality of through holes in a portion in contact with the assembly. In the case of having a plurality of through holes, for example, a solvent or alkali metal ions can be transmitted. Examples of the material constituting the pressing unit include metal, glass, resin, and nonwoven fabric.

  Another pressurizing unit includes a pressurizing unit that pressurizes the aggregate by forming a flow of solvent that passes through the aggregate. As a specific means for pressurizing the aggregate with a solvent, for example, a circulation pump can be incorporated.

  When pressurization by the pressurizing unit is performed outside the storage container of (B), for example, the manufacturing system uses a container (hereinafter referred to as a pressurization container) different from the storage container of (B) and pressurization. And a pressurizing unit that pressurizes the container. The mixing container (E) may be a pressurized container.

  In addition, when pressurization by a pressurizing unit is performed in a pressurized container, the storage container of (B) is an aggregate containing divided raw materials and active materials, for example, and the active material is doped with an alkali metal A previous state (ie, a precursor of the electrode material) can be produced. Moreover, when pressurization by a pressurizing unit is performed in a pressurized container, a dispersion liquid in which the divided raw materials are dispersed in a solvent can be produced in the storage container of (B).

(G) Other Configurations The electrode material manufacturing system of the present disclosure may further include a solvent supply unit that supplies a solvent into the storage container of (B). An alkali metal salt or an additive may be dissolved in the solvent. Examples of the solvent supply unit include a device that includes a container that stores a solvent and the like and a liquid feed pump, and further includes a stirring unit that stirs the solvent and the like as necessary.

  In addition, the electrode material manufacturing system of the present disclosure may include a slurry solvent supply unit that mixes an active material and a solvent to prepare a slurry, and supplies the prepared slurry into the storage container of (B). Good. The slurry may contain an alkali metal salt, an additive, a binder, a thickener, a conductive aid and the like. Examples of the slurry solvent supply unit include a container that contains a solvent and the like, a stirring unit that stirs the solvent, and a liquid feed pump.

The electrode material manufacturing system according to the present disclosure may include an inert gas supply unit that supplies an inert gas such as argon into the storage container of (B).
In addition, the electrode material manufacturing system of the present disclosure may include a filtration unit and a drying unit for removing the solvent after the alkali metal is doped into the active material in the solvent.

2. Method for Producing Electrode Material A method for producing an electrode material according to the present disclosure includes a step of dividing at least a part of a raw material containing an alkali metal (hereinafter referred to as a division step) using the electrode material production system according to the present disclosure. .

  Examples of the electrode material include an electrode-forming slurry containing an alkali metal, an active material and a solvent, and an active material doped with an alkali metal. The electrode material is preferably a negative electrode material because the electrode material production system of the present disclosure is suitable for the treatment of the negative electrode active material.

  In the dividing step, since it becomes easy to divide the raw material, it is preferable to divide at least a part of the raw material containing the alkali metal in the solvent accommodated in the storage container (B). ) Is preferably divided by cutting at least part of the raw material containing the alkali metal in the solvent accommodated in the storage container. The solvent used in the dividing step is preferably the same as the solvent used in the dope step described later.

  After the dividing step, for example, the raw material and the active material which are divided in the storage container (B) or in the mixing container (E) different from the storage container (B) are included. A step of forming an aggregate can be performed.

  After forming the aggregate, for example, in the storage container of (B) or outside the storage container of (B), preferably in the presence of a solvent, the active material contained in the aggregate and the divided raw materials By bringing these into contact with each other, a step of doping an active material with an alkali metal (hereinafter referred to as a doping step) can be performed.

  As the solvent used in the dope process, those mentioned in the section of “1. Electrode material production system” can be used, and the following solvents are particularly preferable. That is, ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyrolactone, acetonitrile, dimethoxyethane, tetrahydrofuran, dioxolane, methylene chloride, sulfolane and the like are preferable.

The solvent may be a single component or a mixed solvent of two or more components. It is preferable that an alkali metal salt such as a lithium salt or a sodium salt is dissolved in the solvent. Examples of the anion moiety constituting the alkali metal salt include phosphorus anions having a fluoro group such as PF ₆ ⁻ , PF ₃ (C ₂ F ₅ ) ₃ ⁻ , PF ₃ (CF ₃ ) ₃ ⁻ , and the like; BF ₄ ⁻ , Boron anions having a fluoro group or a cyano group such as BF ₂ (CF) ₂ ⁻ , BF ₃ (CF ₃ ) ⁻ and B (CN) ₄ ^— ; N (FSO ₂ ) ₂ ⁻ , N (CF ₃ SO ₂ ) _{2 ^{-, N (C 2 F 5}} SO 2) 2 - sulfonyl imide anion having a fluoro group such as; _{CF 3} SO 3 ^- is an organic sulfonate anion having a fluoro group and the like. In the solvent, a single alkali metal salt may be dissolved, or two or more alkali metal salts may be dissolved.

  The concentration of the alkali metal ion (alkali metal salt) in the solution in which the alkali metal salt is dissolved (hereinafter referred to as the electrolyte for doping) is preferably 0.1 mol / L or more, more preferably 0.5 to Within the range of 1.5 mol / L. When it is within this range, doping of the alkali metal to the active material proceeds efficiently.

  The solvent further dissolves additives such as vinylene carbonate, vinyl ethylene carbonate, 1-fluoroethylene carbonate, 1- (trifluoromethyl) ethylene carbonate, succinic anhydride, maleic anhydride, propane sultone, and diethylsulfone. It may be.

  Examples of the method of bringing the divided raw material and active material into contact in the dope process include a method of kneading and mixing the two, and a method of applying ultrasonic vibration to both in the electrolyte for doping. Aspects are disclosed in JP 2012-204310 A, JP 2012-209195 A, JP 2014-51414 A, and the like.

  Moreover, in the dope process, the divided raw material and the active material can be brought into contact by pressurizing the aggregate. The pressurizing pressure is preferably in the range of 0.001 to 20 MPa. When the pressure is within this range, the balance between the contact resistance between the active material particles and the diffusion of alkali metal ions is good, and the doping of the alkali metal to the active material proceeds efficiently. The pressurization time can be appropriately set according to the type and amount of the active material, the shape of the storage container and the pressing means, the amount of alkali metal dope, and the like.

  In the dope process, when the active material and the divided raw material are brought into contact by pressurizing the aggregate, the aggregate may further contain a conductive additive. Examples of the conductive assistant include carbon black, vapor grown carbon fiber, metal powder other than alkali metal, and the like. The dope rate can be increased by incorporating a conductive additive in the aggregate.

  When the dope process is performed outside the storage container (B), the raw material and the active material divided in the storage container (B) are preferably mixed with a solvent in advance, or (B) After the raw material divided in the storage container is dispersed in a solvent, the obtained dispersion and the active material are preferably mixed in the mixing container (E). In this case, since the divided raw material can be uniformly dispersed in the active material, it becomes easy to uniformly dope the alkali metal throughout the active material in the subsequent doping step.

  When performing a dope process in the said (B) storage container, the order which supplies the divided raw material, active material, and solvent in the said (B) storage container can be selected suitably. For example, after the active material and the solvent are previously supplied into the storage container (B), the divided raw materials can be supplied into the storage container (B). Moreover, after producing the cake containing an active material and a solvent in the storage container (B), the divided raw materials may be supplied into the storage container (B).

  Moreover, after supplying the raw material divided | segmented in the said (B) storage container, you may supply the slurry containing an active material and a solvent in the said (B) storage container by the said slurry solvent supply unit. A step of supplying the raw material divided into the storage container of (B), and a step of supplying a slurry containing an active material and a solvent into the storage container of (B) by the slurry solvent supply unit. It may be repeated alternately.

The storage container (B) is preferably filled with an inert gas such as argon, and the dew point in the storage container (B) is preferably controlled to −50 ° C. or lower.
In the manufacturing method of the electrode material of the present disclosure, the active material and the divided raw material are contained in the storage container (B) or in the mixing container (E) different from the storage container (B). , An organic solvent, a binder or the like may be mixed. By this treatment, an electrode forming slurry containing an alkali metal and an active material can be produced.

  As an organic solvent, N-methylpyrrolidone etc. other than the organic solvent mentioned above are mentioned. Examples of the binder include rubber-based binders such as styrene-butadiene rubber (SBR) and NBR; fluorine-based resins such as polytetrafluoroethylene and polyvinylidene fluoride; polypropylene, polyethylene, disclosed in JP2009-246137A Fluorine-modified (meth) acrylic binder, polyimide and the like.

  Other components contained in the electrode-forming slurry include, for example, carbon black, graphite, vapor-grown carbon fiber, metal powder and the like; carboxyl methyl cellulose, its Na salt or ammonium salt, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose , Hydroxypropylcellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and the like.

3. Electrode Manufacturing Method The electrode manufacturing method of the present disclosure manufactures an electrode using the electrode material manufactured by the electrode material manufacturing method. The electrode to be manufactured may be a positive electrode or a negative electrode, but a negative electrode is preferable because the method for manufacturing an electrode material of the present disclosure is suitable for manufacturing a negative electrode material.

  An electrode includes, for example, a current collector and an active material layer provided on the surface of the current collector. As a method for producing such an electrode, for example, an electrode-forming slurry is produced by the method described in the above-mentioned section “2. The method of forming a material layer is mentioned. The electrode forming slurry corresponds to the electrode material.

  In addition, as an electrode manufacturing method, an active material doped with an alkali metal is manufactured by the method described in the above section “2. Method of manufacturing electrode material”, and then an active material doped with an alkali metal is contained A method of producing a slurry and further forming an active material layer on the current collector using the slurry is exemplified. The active material doped with alkali metal corresponds to the electrode material.

  As the current collector, in the case of producing a negative electrode, for example, a metal foil such as copper, nickel, and stainless steel is preferable. Further, the current collector may be one in which a conductive layer mainly composed of a carbon material is formed on the metal foil. The thickness of the current collector can be, for example, 5 to 50 μm. The active material layer on the current collector is formed, for example, by applying a slurry on the current collector and drying it. The thickness of the active material layer is not particularly limited, but is, for example, 5 to 500 μm, preferably 10 to 200 μm, and particularly preferably 10 to 100 μm.

  The slurry containing an active material doped with an alkali metal may contain a binder, an organic solvent, and other components in addition to the active material. As the binder, the organic solvent, and other components, those similar to the binder, organic solvent, and other components listed in the above-mentioned section “2. Method for producing electrode material” can be used. Further, as disclosed in JP-A-2004-281162, etc., an electrode containing a gel electrolyte can be produced by using a gelling agent as a binder and adding an electrolyte to the slurry.

  An electrode manufactured by the electrode manufacturing method of the present disclosure has a small irreversible capacity. In addition, in a battery or a capacitor including an electrode manufactured by the electrode manufacturing method of the present disclosure, decomposition of the electrolytic solution on the electrode is suppressed.

4). Capacitor Manufacturing Method A capacitor manufacturing method of the present disclosure is a method of manufacturing a capacitor including a positive electrode, a negative electrode, and an electrolyte, and includes a step of manufacturing the negative electrode by the electrode manufacturing method of the present disclosure. The capacitor is not particularly limited as long as it is a capacitor using insertion / extraction of alkali metal ions, and examples thereof include a lithium ion capacitor and a sodium ion capacitor. Among these, a lithium ion capacitor is preferable.

  The method for manufacturing a capacitor according to the present disclosure includes, for example, a step of manufacturing a negative electrode by the electrode manufacturing method, a step of manufacturing a positive electrode, a step of storing the obtained negative electrode and positive electrode in an exterior body, and an electrolyte in the exterior body Injecting.

The process for producing the positive electrode is not particularly limited, and a known method can be adopted. It is preferable to use activated carbon as the positive electrode active material contained in the positive electrode.
As a process of housing the negative electrode and the positive electrode in the exterior body, for example, a laminate in which three or more plate-like structural units each including the positive electrode and the negative electrode and a separator interposed therebetween are laminated is manufactured. The method of enclosing in an exterior film is mentioned.

  Further, as another method of housing the negative electrode and the positive electrode in the exterior body, a laminate in which a band-shaped structural unit composed of the positive electrode and the negative electrode and a separator interposed therebetween is wound, and the laminate is rectangular or The method of accommodating in a cylindrical container is mentioned. As a separator, the nonwoven fabric or porous film which uses a cellulose rayon, polyethylene, a polypropylene, polyamide, polyester, a polyimide etc. as a raw material can be mentioned, for example.

  The step of injecting the electrolyte into the exterior body is not particularly limited, and a known method can be employed. The electrolyte is usually in a liquid form, and the same electrolyte as the dope electrolyte described in the above section “2. Method for producing electrode material” can be used. The electrolyte may have a gel or solid form for the purpose of preventing leakage.

In the capacitor manufactured by the method for manufacturing a capacitor according to the present disclosure, since the decomposition of the electrolyte solution on the negative electrode is suppressed, the amount of gas generated when held in a charged state is small.
5. Battery Manufacturing Method A battery manufacturing method of the present disclosure is a method of manufacturing a battery including a positive electrode, a negative electrode, and an electrolyte, and includes a step of manufacturing the negative electrode by the electrode manufacturing method of the present disclosure. The battery is not particularly limited as long as it uses insertion / extraction of alkali metal ions, and may be a primary battery or a secondary battery. Examples of the battery include a lithium ion secondary battery and a sodium ion secondary battery. Among these, a lithium ion secondary battery is preferable.

  The battery manufacturing method of the present disclosure is basically the same as the method described in “4. Capacitor manufacturing method” except for the type of positive electrode active material to be used. As the positive electrode active material, an organic active material such as a nitroxy radical compound and oxygen can be used in addition to those exemplified in the section of “1. Electrode material production system”.

  Since the battery manufactured by the battery manufacturing method of the present disclosure includes a negative electrode having a small irreversible capacity, the energy density is high and the cycle characteristics are also excellent.

Claims (15)

A storage container for storing at least one of an active material and a solvent;
A raw material processing unit that divides at least part of the raw material containing the alkali metal and supplies the raw material into the storage container;
An electrode material manufacturing system comprising: The manufacturing system according to claim 1,
The raw material processing unit is a manufacturing system in which the raw material is divided by cutting. The manufacturing system according to claim 1 or 2,
A manufacturing system further comprising a mixing unit that mixes the divided raw material and at least one of the active material and the solvent stored in the storage container. The manufacturing system according to any one of claims 1 to 3,
The raw material processing unit is a manufacturing system for dividing the raw material in the form of a sheet or a wire. The manufacturing system according to claim 4,
A production system further comprising a raw material production unit for producing a raw material having the form of the sheet or the wire by extrusion or rolling. It is a manufacturing system given in any 1 paragraph of Claims 1-5,
A manufacturing system further comprising a pressurizing unit that statically pressurizes an assembly including the divided raw material and the active material. The manufacturing system according to any one of claims 1 to 6,
A manufacturing system further comprising a mixing container for mixing the divided raw material, the active material, and the solvent. The manufacturing system according to any one of claims 1 to 7,
The said raw material processing unit is a manufacturing system arrange | positioned above the opening part with which the said storage container is provided, or the bottom face of the said storage container. A manufacturing system according to any one of claims 1 to 8,
A manufacturing system in which the electrode material is an active material doped with an alkali metal. The manufacturing system according to any one of claims 1 to 9,
The manufacturing system whose electrode material is the slurry for electrode formation containing an alkali metal, an active material, and a solvent.   The manufacturing method of an electrode material including the process of dividing | segmenting at least one part of the raw material containing an alkali metal using the manufacturing system of any one of Claims 1-10. It is a manufacturing method of the electrode material according to claim 11,
The manufacturing method of the electrode material which further includes the dope process which dopes the said alkali metal to the said active material.   The manufacturing method of the electrode which manufactures an electrode using the electrode material manufactured by the manufacturing method of Claim 11 or 12. A method of manufacturing a capacitor comprising a positive electrode, a negative electrode and an electrolyte,
A method for manufacturing a capacitor, comprising the step of manufacturing the negative electrode by the manufacturing method according to claim 13. A method for producing a battery comprising a positive electrode, a negative electrode and an electrolyte,
A method for producing a battery, comprising the step of producing the negative electrode by the production method according to claim 13.

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