WO2019208734A1 - Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité - Google Patents

Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité Download PDF

Info

Publication number
WO2019208734A1
WO2019208734A1 PCT/JP2019/017795 JP2019017795W WO2019208734A1 WO 2019208734 A1 WO2019208734 A1 WO 2019208734A1 JP 2019017795 W JP2019017795 W JP 2019017795W WO 2019208734 A1 WO2019208734 A1 WO 2019208734A1
Authority
WO
WIPO (PCT)
Prior art keywords
storage device
positive electrode
electricity storage
active material
conductive layer
Prior art date
Application number
PCT/JP2019/017795
Other languages
English (en)
Japanese (ja)
Inventor
矢野　雅也
弘義 武
千里 後藤
健吾 山内
Original Assignee
日東電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2019065608A external-priority patent/JP2020072251A/ja
Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to EP19793046.4A priority Critical patent/EP3786992A1/fr
Priority to US17/050,327 priority patent/US20210118625A1/en
Priority to KR1020207029905A priority patent/KR20210004992A/ko
Priority to CN201980028268.7A priority patent/CN112041955A/zh
Publication of WO2019208734A1 publication Critical patent/WO2019208734A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/04—Hybrid capacitors
    • H01G11/06—Hybrid capacitors with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/26—Electrodes characterised by their structure, e.g. multi-layered, porosity or surface features
    • H01G11/28—Electrodes characterised by their structure, e.g. multi-layered, porosity or surface features arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/30—Electrodes characterised by their material
    • H01G11/48—Conductive polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/137—Electrodes based on electro-active polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/60—Selection of substances as active materials, active masses, active liquids of organic compounds
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to an electrode for an electricity storage device and an electricity storage device.
  • micro-hybrid that attracts regenerative energy associated with vehicle braking as electric energy has attracted attention.
  • rapid charging and discharging of power storage devices such as electric double layer capacitors and lithium ion capacitors is necessary.
  • an electrochemically active polymer such as polyaniline as an active material for such an electricity storage device.
  • Patent Document 1 describes a positive electrode for an electricity storage device for an electricity storage device having excellent rapid charge / discharge characteristics.
  • This positive electrode contains an active material containing at least one of polyaniline and a polyaniline derivative, a conductive additive, and a binder.
  • the ratio of the oxidized form of polyaniline in the active material is 45% by mass or more of the whole polyaniline active material.
  • the binder the sum of the polar term and the hydrogen bond term of the Hansen solubility parameter is 20 MPa 1/2 or less.
  • a positive electrode is produced by applying a slurry on a current collector layer such as an aluminum foil.
  • the present invention provides a positive electrode for an electricity storage device that is advantageous for improving the durability of an electricity storage device while containing an electrochemically active polymer as an active material. Moreover, this invention provides the electrical storage device provided with such a positive electrode.
  • the present invention An active material layer containing an electrochemically active polymer and a conductive aid; A current collector, A conductive layer disposed between the active material layer and the current collector and in contact with the active material layer and the current collector;
  • the conductive layer contains conductive particles and a binder in contact with the outer surface of the conductive particles, The content of the binder in the conductive layer is 3% or more on a mass basis.
  • a positive electrode for an electricity storage device is provided.
  • the present invention also provides: An electrolyte layer; A negative electrode disposed in contact with the first main surface of the electrolyte layer; The positive electrode for an electricity storage device, which is disposed in contact with the second main surface of the electrolyte layer, An electricity storage device is provided.
  • the above positive electrode for an electricity storage device is advantageous for improving the durability of the electricity storage device. Moreover, said electrical storage device can exhibit favorable durability.
  • FIG. 1 is a cross-sectional view schematically showing an example of a positive electrode for an electricity storage device according to the present invention.
  • FIG. 2 is a cross-sectional view schematically showing an example of the electricity storage device according to the present invention.
  • activated carbon is used as an active material in the positive electrode of an electricity storage device such as a lithium ion capacitor.
  • Activated carbon has a very large specific surface area, and charging and discharging are performed by physical adsorption and desorption of ions on the surface of the activated carbon in an electricity storage device including a positive electrode including activated carbon. In such an electricity storage device, reactions for charging and discharging are very fast, and rapid charging and discharging are possible.
  • the present inventors obtained a combination of positive electrodes in which an active material layer containing an electrochemically active polymer such as polyaniline as an active material was brought into direct contact with a current collector such as an aluminum foil.
  • AC impedance measurement was performed using a symmetric cell.
  • the impedance of the positive electrode increases in a high frequency region (for example, a region around 100 kHz). This phenomenon does not occur in a positive electrode including activated carbon as an active material, and is a phenomenon peculiar to a positive electrode including an electrochemically active polymer as an active material. It is difficult to say that the positive electrode having such characteristics is desirable in order to improve characteristics relating to rapid charge / discharge of the electricity storage device.
  • the present inventors have studied day and night on the structure of the positive electrode in which the impedance is difficult to increase in the high frequency region.
  • a positive electrode in which impedance is difficult to increase in a high frequency region is obtained by interposing a predetermined conductive layer between an active material layer containing electrochemically active polymer particles and a conductive additive and a current collector. It was found that it can be obtained. Moreover, it has been found that an electricity storage device manufactured using such a positive electrode can exhibit good characteristics with respect to rapid charge / discharge.
  • the binder content in the conductive layer interposed between the active material layer and the current collector has a predetermined relationship. It has further been found that satisfying the above is advantageous from the viewpoint of improving the durability of the electricity storage device.
  • the positive electrode 1 for an electricity storage device includes an active material layer 10, a current collector 20, and a conductive layer 30.
  • the active material layer 10 contains an electrochemically active polymer 12 and a conductive additive 14.
  • the conductive layer 30 is disposed between the active material layer 10 and the current collector 20 and is in contact with the active material layer 10 and the current collector 20.
  • the conductive layer 30 contains conductive particles 32 and a binder 35 that is in contact with the outer surface of the conductive particles 32.
  • the content of the binder 35 in the conductive layer 30 is 3% or more on a mass basis.
  • Electrochemically active polymer particles show a large dimensional change with charge / discharge of the electricity storage device compared to activated carbon. For this reason, when the active material layer containing the electrochemically active polymer particles as an active material and the current collector are in direct contact, the electrochemically active polymer particles accompanying charge / discharge of the electricity storage device It is considered that a large dimensional change affects the interface between the active material layer and the current collector. On the other hand, since the conductive layer 30 contains the conductive particles 32 and the binder 35, it is easy to mitigate the influence of a large dimensional change of the electrochemically active polymer particles accompanying charging / discharging of the electricity storage device.
  • the positive electrode 1 is easy to improve the characteristic regarding the rapid charge / discharge of an electrical storage device.
  • the power storage device manufactured using the positive electrode 1 for power storage devices tends to exhibit high durability.
  • the content of the binder 35 in the conductive layer 30 is in the above range, it is considered that the polymer 12 can be prevented from directly contacting the current collector 20.
  • the current collector 20 can be prevented from being deteriorated by the contact between the polymer 12 and the current collector 20, and the positive electrode 1 for an electricity storage device is likely to exhibit high durability.
  • the dimensional change of the polymer 12 accompanying charging / discharging of the electricity storage device is large.
  • the conductive layer 30 peels from the active material layer 10 and the current collector 20 in spite of a large dimensional change of the polymer 12 due to charging / discharging of the electricity storage device. It is considered difficult.
  • the content of the binder 35 in the conductive layer 30 may be 3% or more or 4% or more on a mass basis. As a result, the power storage device can easily exhibit high durability more reliably.
  • the content of the binder 35 in the conductive layer 30 is, for example, 10% or less on a mass basis. Thereby, the density of the conductive particles 32 in the conductive layer 30 increases, and the internal resistance of the positive electrode 1 tends to decrease.
  • the content of the binder 35 in the conductive layer 30 may be 10% or less or 6% or less on a mass basis.
  • the conductive particles 32 include, for example, a carbon material. In this case, the manufacturing cost of the positive electrode 1 can be kept low.
  • the carbon material used for the conductive particles 32 is, for example, graphite.
  • the conductive particles 32 are bound by the binder 35.
  • a part of the outer surface of the conductive particle 32 is in contact with the active material layer 10, and another part of the outer surface of the conductive particle 32 is in contact with the current collector 20.
  • the binder 35 is not particularly limited as long as it can contact the outer surface of the conductive particles 32 and bind the conductive particles 32.
  • the binder 35 is a polymer such as carboxymethyl cellulose, for example.
  • the binder 35 includes at least one selected from the group consisting of, for example, methyl cellulose, hydroxyethyl cellulose, polyethylene oxide, carboxymethyl cellulose, derivatives thereof, salts thereof, polyolefin, natural rubber, synthetic rubber, and thermoplastic elastomer.
  • the adhesion between the conductive layer 30 and the active material layer 10 or the current collector 20 is likely to increase.
  • the synthetic rubber or thermoplastic elastomer for example, a styrene-butadiene copolymer, an acrylonitrile-butadiene copolymer, or a methyl methacrylate-butadiene copolymer can be used.
  • the binder 35 includes, for example, at least one selected from the group consisting of polyolefin, carboxymethyl cellulose, and styrene-butadiene copolymer. In this case, the adhesion between the conductive layer 30 and the active material layer 10 or the current collector 20 is more likely to increase more reliably.
  • the binder 35 desirably contains at least one of carboxymethyl cellulose and a styrene-butadiene copolymer.
  • the adhesion between the conductive layer 30 and the active material layer 10 tends to increase.
  • the binder 15 of the active material layer 10 described later includes a predetermined component, the adhesion between the conductive layer 30 and the active material layer 10 is likely to increase.
  • the thickness of the conductive layer 30 is measured.
  • the average value of the thickness of the conductive layer 30 determined by this measurement is, for example, 0.5 to 3.0 ⁇ m.
  • the average value of the thickness of the conductive layer 30 is an arithmetic average.
  • the thickness of the conductive layer 30 can be measured, for example, by observing a cross section of the conductive layer 30 using a scanning electron microscope (SEM). The measurement of the thickness of the conductive layer 30 may be performed before the active material layer 10 is formed in the manufacture of the positive electrode 1 or may be performed after the active material layer 10 is formed.
  • the average value of the thickness of the conductive layer 30 may be 0.5 ⁇ m or more, or 1.0 ⁇ m or more. As a result, the power storage device can easily exhibit high durability more reliably.
  • the average value of the thickness of the conductive layer 30 may be 3.0 ⁇ m or less, or may be 1.5 ⁇ m or less. Thereby, it can suppress that the thickness of the positive electrode 1 becomes large.
  • the minimum value of the thickness of the conductive layer 30 measured at the above 10 positions is, for example, 0.1 ⁇ m or more. Thereby, it can suppress more reliably that the polymer 12 contacts the collector 20 directly, and an electrical storage device tends to exhibit high durability.
  • the minimum value of the thickness of the conductive layer 30 measured at the above 10 positions may be 0.2 ⁇ m or more, 0.3 ⁇ m or more, or 0.5 ⁇ m or more. As a result, the power storage device can easily exhibit high durability more reliably.
  • the contact angle of water droplets on the surface formed by the conductive layer 30 is, for example, 100 ° or less.
  • the contact angle of water droplets on the surface of the conductive layer 30 can be measured, for example, according to the sessile drop method in Japanese Industrial Standard JIS R 3257: 1999 before the active material layer 10 is formed.
  • the measurement temperature of the contact angle of the water droplet is 25 ° C.
  • the contact angle of water droplets on the surface of the conductive layer 30 is determined by, for example, exposing the conductive layer 30 by removing at least part of the active material layer 10 by a method such as polishing or cutting after the active material layer 10 is formed. Measurement may be performed on the surface of the conductive layer 30. In addition, at least a part of the current collector 20 may be removed by polishing or cutting to expose the conductive layer 30, and measurement may be performed on the exposed surface of the conductive layer 30.
  • the small contact angle of water droplets on the main surface of the conductive layer 30 is advantageous from the viewpoint of improving the adhesion between the conductive layer 30 and the active material layer 10.
  • the contact angle of the water droplet is desirably 90 ° or less, more desirably 80 ° or less, and further desirably 70 ° or less.
  • the contact angle of this water droplet is, for example, 10 ° or more.
  • the peel strength P of the active material layer 10 with respect to the conductive layer 30 measured by Surface And Interfacial Cutting Analysis System is, for example, 0.15 kN / m or more.
  • the peel strength P is determined by, for example, the following formula (1).
  • the SAICAS measurement mode is a constant speed mode. The cutting speed is 10 ⁇ m / second.
  • FH is the horizontal cutting stress [N] when a SAICAS diamond cutting blade (Daipla, rake angle: 10 °) is moved horizontally at the interface between the active material layer 10 and the conductive layer 30.
  • W is the blade width [m] of the SAICAS cutting blade.
  • SAICAS is a registered trademark of Daipla Corporation.
  • P FH / W (1)
  • the peel strength P is desirably 0.15 kN / m or more, more desirably 0.17 kN / m or more, and further desirably 0.23 kN / m or more.
  • the polymer 12 exists as particles, for example.
  • the average particle diameter of the polymer 12 is not limited to a specific value.
  • the polymer 12 has, for example, an average particle diameter of more than 0.5 ⁇ m and 20 ⁇ m or less.
  • the average particle diameter of the polymer 12 can be determined, for example, by measuring the maximum diameter of the 50 or more polymers 12 when observing 50 or more polymers 12 using an electron microscope such as SEM.
  • the average particle diameter of the polymer 12 may be determined using a particle image analyzer that captures the shape of the particles using a microscope and analyzes them by image analysis.
  • “average particle diameter” refers to the median diameter (D50).
  • the median diameter is a particle size such that the number of particles having a particle size larger than that value is equal to the number of particles having a particle size smaller than that value.
  • the average particle size of the polymer 12 may be 0.5 ⁇ m or less.
  • the content of the polymer 12 in the active material layer 10 is, for example, 1% or more, desirably 5% or more, more desirably 20% or more, and further desirably 40% or more, based on mass. Desirably, it is 60% or more. Thereby, the energy density in an electrical storage device tends to increase.
  • the electrochemically active polymer 12 includes, for example, at least one of polyaniline and a polyaniline derivative. In this case, it is possible to improve characteristics relating to rapid charge / discharge of the electricity storage device more reliably. In addition, the energy density of the electricity storage device tends to increase. Polyaniline and polyaniline derivatives are sometimes collectively referred to as “polyaniline compounds”.
  • Polyaniline is typically obtained by electrolytic polymerization or chemical oxidation polymerization of aniline.
  • Polyaniline derivatives are typically obtained by electropolymerization or chemical oxidative polymerization of aniline derivatives.
  • the aniline derivative has, for example, at least one substituent such as an alkyl group, an alkenyl group, an alkoxy group, an aryl group, an aryloxy group, an alkylaryl group, an arylalkyl group, and an alkoxyalkyl group at a position other than the 4-position of the aniline. Have.
  • Aniline derivatives include, for example, (i) o-substituted anilines such as o-methylaniline, o-ethylaniline, o-phenylaniline, o-methoxyaniline, and o-ethoxyaniline, or (ii) m-methylaniline.
  • M-substituted anilines such as m-ethylaniline, m-methoxyaniline, m-ethoxyaniline, m-phenylaniline and the like.
  • aniline derivative only one kind of aniline derivative may be used, or two or more kinds of aniline derivatives may be used in combination.
  • the polyaniline compound may be doped with a dopant such as protonic acid.
  • the polyaniline and the polyaniline derivative contained in the electrochemically active polymer 12 are desirably dedope when the positive electrode 1 is manufactured. Specifically, the polyaniline and the polyaniline derivative contained in the polymer 12 are in a state in which a dopant such as a proton acid is undope. In this case, the polymer 12 can be appropriately dispersed in the active material layer 10, and the energy density of the electricity storage device can be easily increased.
  • the polymer 12 containing the dedopeed polyaniline or the like is well dispersed in the slurry even if the dispersion medium of the slurry for forming the active material layer 10 is water.
  • the positive electrode 1 is undoped during assembly of the electricity storage device.
  • the polymer 12 is doped in the positive electrode 1 when the electricity storage device is in a charged state.
  • an electrochemically active polymer in a state of being dedoped at the time of manufacturing the positive electrode or at the time of assembling the power storage device is electrochemically doped from the time when charging is started after the assembly of the power storage device. Then, it can be used as an electrical storage device by repeating doping and dedoping of an electrochemically active polymer.
  • the polyaniline and polyaniline derivative contained in the electrochemically active polymer 12 include, for example, 35 to 60% oxidant on a mass basis. In this case, the preservability of the polymer 12 is good, and the polymer 12 can exhibit desirable characteristics as an active material of the positive electrode.
  • the chemical structure of the oxidized form Ox and the reduced form Red of polyaniline is shown in the following formula (a). In the formula (a), each of x and y is an integer of 0 or more.
  • the addition amount of a reducing agent such as phenylhydrazine or an oxidizing agent such as manganese dioxide is relative to polyaniline so that the content of the oxidant in the polyaniline compound is within a predetermined range (35 to 60% on a mass basis). Stoichiometrically adjusted.
  • a reducing agent such as phenylhydrazine or an oxidizing agent such as manganese dioxide
  • An example of the reduction reaction of polyaniline using phenylhydrazine is shown in the following formula (b).
  • the content of the oxidant in the polyaniline compound contained in the electrochemically active polymer 12 can be determined from, for example, a solid state 13 CNMR spectrum.
  • the content of the oxidant in the polyaniline compound contained in the polymer 12 is a ratio A640 / A340 of the absorbance A640 at the absorption maximum near 640 nm and the absorbance A340 at the absorption maximum near 340 nm in the electronic spectrum of the spectrophotometer. It is also possible to obtain it from the expressed oxidation degree index.
  • the content of oxidized form (ratio of oxidized form) in the polyaniline compound contained in polymer 12 can be determined, for example, according to the method described in paragraphs 0040 to 0051 of JP-A-2018-26341.
  • the conductive auxiliary agent 14 included in the active material layer 10 is typically made of a conductive material having a property that does not change depending on the voltage applied for charging / discharging the power storage device.
  • the conductive auxiliary agent 14 can be a conductive carbon material or a metal material.
  • the conductive carbon material is, for example, conductive carbon black such as acetylene black and ketjen black, or fibrous carbon material such as carbon fiber and carbon nanotube.
  • the conductive carbon material is desirably conductive carbon black.
  • the content of the conductive additive 14 in the active material layer 10 is, for example, 1 to 30%, desirably 4 to 25%, and more desirably 4 to 19% on a mass basis.
  • the polymer 12 can be activated more reliably while suppressing the content of the conductive assistant. As a result, it is easy to increase the energy density of the electricity storage device.
  • the active material layer 10 further contains, for example, a binder 15.
  • the binder 15 includes, for example, an elastomer.
  • the elastomer can be natural rubber, synthetic rubber, or thermoplastic elastomer.
  • the binder 15 is typically in contact with the outer surface of the polymer 12 and the outer surface of the conductive aid 14.
  • the binder 15 binds the electrochemically active polymer 12 and the conductive aid 14.
  • the polymer 12 and the conductive additive 14 are bound by the binder 15.
  • the active material layer 10 has, for example, holes 16.
  • the holes 16 are formed so as to continue from one main surface of the active material layer 10 to the other main surface.
  • the electrolyte 16 is impregnated with the electrolyte 16.
  • the binder 15 contains an elastomer, the binder 15 is easily deformed without generating a large stress in accordance with a dimensional change of the electrochemically active polymer particles accompanying charging / discharging of the electricity storage device. Thereby, it is thought that the characteristic regarding the rapid charge / discharge of an electrical storage device is easy to improve.
  • the binder 15 includes, for example, a rubber material.
  • the rubber material can be, for example, a styrene-butadiene copolymer, an acrylonitrile-butadiene copolymer, or a methyl methacrylate-butadiene copolymer.
  • the total of the polar term and the hydrogen bond term in the Hansen solubility parameter of the binder 15 is, for example, 20 MPa 1/2 or less.
  • the affinity between the binder 15 and the polymer 12 is good, and the conductive additive 14 is likely to come into contact with the polymer 12.
  • the adhesion between the active material layer 10 and the conductive layer 30 tends to increase.
  • the calculation for determining the Hansen solubility parameter can be performed according to the method described in Charles M. Hansen, Hansen Solubility Parameters: A Users Handbook (CRC Press, 2007).
  • Hansen Solubility Parameters in Practice HSPiP
  • HSPiP Hansen Solubility Parameters in Practice
  • the sum of the polar term and the hydrogen bond term in the Hansen solubility parameter of the composite binder is determined by summing up the product of the Hansen solubility parameter of each component constituting the binder and the mass-based component ratio of each component. it can.
  • the total of the polar term and the hydrogen bond term in the Hansen solubility parameter of the binder 15 is desirably 19 MPa 1/2 or less, more desirably 12 MPa 1/2 or less, and further desirably 8 MPa 1/2 or less. .
  • the predetermined component can be, for example, a rubber material such as methyl cellulose, hydroxyethyl cellulose, polyethylene oxide, carboxymethyl cellulose, derivatives thereof, salts thereof, or a styrene-butadiene copolymer.
  • the predetermined component is carboxymethyl cellulose or a styrene-butadiene copolymer.
  • the content of the binder 15 in the active material layer 10 is, for example, 1 to 30%, desirably 4 to 25%, and more desirably 4 to 18% on a mass basis.
  • the polymer 12 can be appropriately dispersed in the active material layer 10 while suppressing the content of the binder 15.
  • it is possible to improve characteristics related to rapid charge / discharge of the electricity storage device, and to easily increase the energy density in the electricity storage device.
  • the active material layer 10 may contain an active material other than the electrochemically active polymer 12 as necessary.
  • the active material other than the polymer 12 is, for example, a carbon material such as activated carbon.
  • the activated carbon can be alkali activated carbon, water vapor activated activated carbon, gas activated activated carbon, or zinc chloride activated activated carbon.
  • the active material layer 10 may further contain additives such as a thickener as necessary.
  • the thickener is, for example, methyl cellulose, hydroxyethyl cellulose, polyethylene oxide, carboxymethyl cellulose, derivatives thereof, or salts thereof. Of these, carboxymethylcellulose, its derivatives, or salts thereof are desirably used as thickeners.
  • the content of the thickener in the active material layer 10 is, for example, 1 to 20%, desirably 1 to 10%, and more desirably 1 to 8% on a mass basis.
  • the current collector 20 is, for example, a foil or mesh made of a metal material such as nickel, aluminum, and stainless steel.
  • the current collector 20 is prepared, and the conductive layer 30 is formed on the main surface of the current collector 20.
  • the conductive layer 30 is formed by, for example, coating, sputtering, vapor deposition, ion plating, or CVD using a predetermined raw material.
  • the conductive layer 30 is formed by coating the main surface of the current collector 20 with a slurry prepared by dispersing the conductive particles 32 and the binder 35 in a dispersion medium, and drying the coating film. Can be formed.
  • a slurry prepared by dispersing the electrochemically active polymer 12, the conductive auxiliary agent 14, and the binder 15 in the dispersion medium is applied to the surface of the conductive layer 30 to form a coating film.
  • the active material layer 10 can be formed by drying. In this way, the positive electrode 1 can be produced.
  • additives such as an active material other than the polymer 12 and a thickener are added to the slurry for forming the active material layer 10 as necessary.
  • the electricity storage device 5 can be manufactured using the positive electrode 1.
  • the electricity storage device 5 includes an electrolyte layer 3, a negative electrode 2, and a positive electrode 1.
  • the negative electrode 2 is disposed in contact with the first main surface of the electrolyte layer 3.
  • the positive electrode 1 is disposed in contact with the second main surface of the electrolyte layer 3.
  • the active material layer 10 of the positive electrode 1 is in contact with the second main surface of the electrolyte layer 3.
  • the electrolyte layer 3 is disposed between the positive electrode 1 and the negative electrode 2. Since the electricity storage device 5 includes the positive electrode 1, it can exhibit good characteristics with respect to rapid charge / discharge.
  • the electrolyte layer 3 is composed of an electrolyte.
  • the electrolyte layer 3 is a sheet made of a solid electrolyte or a sheet in which a separator is impregnated with an electrolytic solution, for example.
  • the electrolyte layer 3 is a sheet made of a solid electrolyte, the electrolyte layer 3 itself may also serve as a separator.
  • the electrolyte includes a solute, and optionally a solvent and various additives.
  • a solute for example, a metal ion such as lithium ion and a predetermined counter ion for the metal ion are combined.
  • the counter ion is, for example, a sulfonate ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, a hexafluoroarsenic ion, a bis (trifluoromethanesulfonyl) imide ion, a bis (pentafluoroethanesulfonyl) imide ion, or Halogen ion.
  • electrolyte examples include LiCF 3 SO 3 , LiClO 4 , LiBF 4 , LiPF 6 , LiAsF 6 , LiN (SO 2 CF 3 ) 2 , LiN (SO 2 C 2 F 5 ), LiN (SO 2 F) 2 , And LiCl.
  • the solvent in the electrolyte is a nonaqueous solvent (organic solvent) such as a carbonate compound, a nitrile compound, an amide compound, and an ether compound.
  • organic solvent such as a carbonate compound, a nitrile compound, an amide compound, and an ether compound.
  • the solvent include ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, acetonitrile, propyronitrile, N, N′-dimethylacetamide, N-methyl-2-pyrrolidone, dimethoxyethane, Diethoxyethane and ⁇ -butyrolactone.
  • the solvent in the electrolyte one type of solvent may be used alone, or two or more types of solvents may be used in combination.
  • dissolved the solute in said solvent may be called "electrolytic solution.”
  • the electrolyte may contain an additive as necessary.
  • the additive is, for example, vinylene carbonate or fluoroethylene carbonate.
  • the negative electrode 2 includes, for example, an active material layer 60 and a current collector 70.
  • the active material layer 60 includes a negative electrode active material.
  • the negative electrode active material is a material capable of inserting and removing metals or ions.
  • metallic lithium, a carbon material capable of inserting and removing lithium ions by an oxidation-reduction reaction, a transition metal oxide, silicon, and tin are desirably used.
  • the active material layer 60 is in contact with the first main surface of the electrolyte layer 3.
  • Examples of the carbon material capable of inserting and removing lithium ions include (i) activated carbon, (ii) coke, (iii) pitch, (iv) a fired body of phenol resin, polyimide, and cellulose, and (v) artificial graphite. , (Vi) natural graphite, (vii) hard carbon, or (vii) soft carbon.
  • a carbon material capable of inserting and removing lithium ions is used as a main component of the negative electrode.
  • a main component means the component contained most by mass reference
  • the current collector 70 is a foil or mesh made of a metal material such as nickel, aluminum, stainless steel, and copper.
  • the negative electrode 2 it is also possible to use a lithium pre-doped negative electrode in which a lithium material is doped in advance in a carbon material such as graphite, hard carbon, or soft carbon.
  • a separator is typically disposed between the positive electrode 1 and the negative electrode 2.
  • the separator prevents an electrical short circuit between the positive electrode 1 and the negative electrode 2.
  • the separator is, for example, a porous sheet that is electrochemically stable and has high ion permeability, desired mechanical strength, and insulating properties.
  • the material of the separator is desirably a porous film made of a resin such as (i) paper, (ii) non-woven fabric, (iii) polypropylene, polyethylene, and polyimide.
  • a separator is disposed between the positive electrode 1 and the negative electrode 2 to obtain a laminate.
  • This laminate is placed in a package made of an aluminum laminate film and vacuum dried.
  • an electrolytic solution is injected into the vacuum-dried package and the package is sealed, so that the power storage device 5 can be manufactured.
  • the manufacturing process of the electricity storage device 5 such as injection of the electrolytic solution into the package is desirably performed in an inert gas atmosphere such as ultra-high purity argon gas using a glove box.
  • the electricity storage device 5 may be formed into a shape such as a film shape, a sheet shape, a square shape, a cylindrical shape, and a button shape using a package other than a package made of an aluminum laminate film.
  • Example 1 In a glass beaker containing 138 g of ion-exchanged water, 84.0 g of tetrafluoroboric acid aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd., reagent special grade) with a concentration of 42% by mass (substance amount of tetrafluoroboric acid: 0.402 mol) was added. In addition, 10.0 g (0.107 mol) of aniline was further added while stirring with a magnetic stirrer. Immediately after the aniline was added to the tetrafluoroboric acid aqueous solution, the aniline was dispersed as oily droplets in the tetrafluoroboric acid aqueous solution.
  • the mixture containing the reaction product was further stirred for 100 minutes while cooling. Then, using a Buchner funnel and a suction bottle, the obtained solid was No. It filtered under reduced pressure with 2 filter papers (made by Toyo Filter Paper Co., Ltd.) to obtain a powder.
  • the powder was stirred and washed in an aqueous solution of about 2 mol / L tetrafluoroboric acid using a magnetic stirrer. Next, this powder was stirred and washed several times with acetone and filtered under reduced pressure. The obtained powder was vacuum-dried at room temperature (25 ° C.) for 10 hours to obtain 12.5 g of conductive polyaniline having tetrafluoroboric acid as a dopant.
  • the conductive polyaniline was a bright green powder.
  • the conductive polyaniline powder in the above doped state was placed in a 2 mol / L sodium hydroxide aqueous solution and stirred in a 3 L separable flask for 30 minutes, and the dopant tetrafluoroboric acid was dedoped by a neutralization reaction.
  • the dedoped polyaniline was washed with water until the filtrate became neutral, then stirred and washed in acetone, and filtered under reduced pressure using a Buchner funnel and a suction bottle to obtain a dedoped polyaniline powder on No. 2 filter paper. . This was vacuum-dried at room temperature for 10 hours to obtain a brown oxidatively dedoped polyaniline powder.
  • the average particle diameter (D50) of the polyaniline powder was 3 ⁇ m.
  • the average particle size of the polyaniline powder was calculated using Morphologi G3 manufactured by Malvern.
  • the oxidation degree index of this polyaniline powder was determined to be 0.86. Moreover, the ratio of the polyaniline oxidized form in the whole polyaniline calculated
  • the copolymerization ratio of styrene: butadiene [1,4 body]: butadiene [1,2 body] was 61: 31: 8.
  • the solid concentration in the slurry for forming an active material layer was 30% by mass.
  • the conductive layer forming slurry according to Example 1 is obtained by mixing and stirring 18 parts by mass of carbon black as conductive particles, 4 parts by mass of styrene-butadiene copolymer (SBR) as a binder, and 78 parts by mass of pure water.
  • SBR styrene-butadiene copolymer
  • the copolymerization ratio of styrene: butadiene was 42:58.
  • the binder content in the solid content of the conductive layer forming slurry was 4% on a mass basis.
  • An aluminum foil having a thickness of 20 ⁇ m was prepared as a current collector.
  • the slurry for forming the conductive layer was applied to one main surface of the aluminum foil to form a coating film.
  • This coating film was dried in an environment of 120 ° C. for 10 minutes to form a conductive layer according to Example 1, and a current collector with a conductive layer according to Example 1 was obtained.
  • the coating thickness is adjusted to 185 ⁇ m with a doctor blade type applicator with a micrometer, and the active material layer is formed on the conductive layer at a coating speed of 10 mm / second.
  • the forming slurry was applied to form a coating film.
  • this coating film was allowed to stand at room temperature (25 ° C.) for 45 minutes, and then dried on a hot plate having a temperature of 100 ° C. to form an active material layer. In this way, a positive electrode according to Example 1 was produced.
  • the thickness of the active material layer was 73 ⁇ m.
  • this laminate cell is taken out from the glove box, and is equivalent to 0.2 C with respect to the capacity of the graphite negative electrode sheet in a potential range of 2.0 V to 0.01 V in a thermostat kept at 25 ° C. 3 cycles of charge and discharge were performed at the current value, and finally, a reaction for inserting lithium ions into the graphite was performed up to a capacity of 75% with respect to the capacity of the graphite negative electrode sheet. In this way, a laminate cell including a negative electrode sheet pre-doped with lithium was produced.
  • the laminate cell including the negative electrode sheet pre-doped with lithium was put into the glove box again.
  • the sealing part of the laminate cell was cut out, and the negative electrode sheet pre-doped with lithium was taken out.
  • these were stacked so that the separator was positioned between the positive electrode according to Example 1 and the negative electrode sheet pre-doped with lithium.
  • a non-woven fabric product name: TF40-50, manufactured by Nippon Kogyo Paper Industries Co., Ltd.
  • a current collector tab was attached to the positive electrode.
  • the laminate of the positive electrode, the separator, and the negative electrode sheet was put into a bag-shaped package made of an aluminum laminate film.
  • Example 2 Conductive layer formation according to Example 2 in the same manner as in Example 1 except that the content of each component was changed so that the content of the binder in the solid content of the slurry for forming the conductive layer was 6% on a mass basis.
  • a slurry was prepared.
  • a positive electrode according to Example 2 was obtained in the same manner as in Example 1 except that the slurry for forming a conductive layer according to Example 2 was used instead of the slurry for forming a conductive layer according to Example 1.
  • a lithium ion capacitor according to Example 2 was obtained in the same manner as in Example 1 except that the positive electrode according to Example 2 was used instead of the positive electrode according to Example 1.
  • Example 3 Conductive layer formation according to Example 3 in the same manner as in Example 1 except that the content of each component was changed so that the content of the binder in the solid content of the slurry for forming the conductive layer was 10% on a mass basis.
  • a slurry was prepared.
  • a positive electrode according to Example 3 was obtained in the same manner as in Example 1 except that the slurry for forming a conductive layer according to Example 3 was used instead of the slurry for forming a conductive layer according to Example 1.
  • a lithium ion capacitor according to Example 3 was obtained in the same manner as in Example 1 except that the positive electrode according to Example 3 was used instead of the positive electrode according to Example 1.
  • the lithium ion capacitor according to the example and the comparative example is taken out from the glove box, and the lithium ion capacitor according to the example and the comparative example is fully charged at an upper limit voltage of 3.8 V inside the thermostat kept at 60 ° C.
  • a float test that keeps (SOC: 100%) was performed for 500 hours, and the time change of the discharge capacity and the time change of the series resistance were measured.
  • the durability of the lithium ion capacitor according to each example was superior to that of the lithium ion capacitor according to Comparative Example 1.
  • the binder content in the positive electrode conductive layer according to Examples 1 and 2 was larger than the binder content in the positive electrode conductive layer according to Comparative Example 1. Thereby, it is considered that the durability of the lithium ion capacitor according to each example was superior to that of the lithium ion capacitor according to Comparative Example 1.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

L'invention concerne une électrode positive 1 pour des dispositifs de stockage d'électricité comprenant une couche de matériau actif 10, un collecteur de courant 20 et une couche électroconductrice. La couche de matériau actif 10 comprend un polymère électrochimiquement actif 12 et un agent auxiliaire électroconducteur 14. La couche électroconductrice 30 est disposée entre la couche de matériau actif 10 et le collecteur de courant 20, et est en contact avec la couche de matériau actif 10 et le collecteur de courant 20. La couche électroconductrice 30 comprend des particules électroconductrices 32 et un liant 35 qui est en contact avec la surface externe de chacune des particules électroconductrices 32. La teneur en liant dans la couche électroconductrice est supérieure ou égale à 3 % en masse.
PCT/JP2019/017795 2018-04-26 2019-04-25 Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité WO2019208734A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP19793046.4A EP3786992A1 (fr) 2018-04-26 2019-04-25 Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité
US17/050,327 US20210118625A1 (en) 2018-04-26 2019-04-25 Positive electrode for power storage device and power storage device
KR1020207029905A KR20210004992A (ko) 2018-04-26 2019-04-25 축전 디바이스용 정극 및 축전 디바이스
CN201980028268.7A CN112041955A (zh) 2018-04-26 2019-04-25 蓄电装置用正极及蓄电装置

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP2018084706 2018-04-26
JP2018-084706 2018-04-26
JP2018204261 2018-10-30
JP2018-204261 2018-10-30
JP2019-065608 2019-03-29
JP2019065608A JP2020072251A (ja) 2018-04-26 2019-03-29 蓄電デバイス用正極及び蓄電デバイス

Publications (1)

Publication Number Publication Date
WO2019208734A1 true WO2019208734A1 (fr) 2019-10-31

Family

ID=68294037

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/017795 WO2019208734A1 (fr) 2018-04-26 2019-04-25 Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité

Country Status (1)

Country Link
WO (1) WO2019208734A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014123449A (ja) * 2012-12-20 2014-07-03 Nitto Denko Corp 蓄電デバイス用電極およびその製造方法、並びに蓄電デバイス
JP2015170739A (ja) * 2014-03-07 2015-09-28 船井電機株式会社 蓄電デバイス
JP2016081704A (ja) * 2014-10-16 2016-05-16 東洋インキＳｃホールディングス株式会社 導電性組成物、蓄電デバイス用電極、及び蓄電デバイス
JP2016197596A (ja) * 2016-05-11 2016-11-24 株式会社Uacj 集電体、電極構造体、非水電解質電池及び蓄電部品
WO2018021513A1 (fr) * 2016-07-29 2018-02-01 日東電工株式会社 Électrode positive pour dispositif de stockage d'énergie, et dispositif de stockage d'énergie
JP2018026341A (ja) 2016-07-29 2018-02-15 日東電工株式会社 蓄電デバイス用正極および蓄電デバイス

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014123449A (ja) * 2012-12-20 2014-07-03 Nitto Denko Corp 蓄電デバイス用電極およびその製造方法、並びに蓄電デバイス
JP2015170739A (ja) * 2014-03-07 2015-09-28 船井電機株式会社 蓄電デバイス
JP2016081704A (ja) * 2014-10-16 2016-05-16 東洋インキＳｃホールディングス株式会社 導電性組成物、蓄電デバイス用電極、及び蓄電デバイス
JP2016197596A (ja) * 2016-05-11 2016-11-24 株式会社Uacj 集電体、電極構造体、非水電解質電池及び蓄電部品
WO2018021513A1 (fr) * 2016-07-29 2018-02-01 日東電工株式会社 Électrode positive pour dispositif de stockage d'énergie, et dispositif de stockage d'énergie
JP2018026341A (ja) 2016-07-29 2018-02-15 日東電工株式会社 蓄電デバイス用正極および蓄電デバイス

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
CHARLES M. HANSEN: "Hansen Solubility Parameters: A Users Handbook", CRC PRESS, article "2007"

Similar Documents

Publication Publication Date Title
US7968232B2 (en) Cathode and lithium battery including the same
US10062925B2 (en) Electrolyte solution for lithium secondary battery and lithium secondary battery
KR20190049585A (ko) 전기화학소자용 음극 활물질, 상기 음극 활물질을 포함하는 음극 및 이를 포함하는 전기화학소자
US20190267627A1 (en) Positive electrode for power storage device, and power storage device
EP2913879B1 (fr) Batterie secondaire à électrolyte non aqueux et procédé de fabrication de celle-ci
JP6304746B2 (ja) リチウムイオン二次電池
KR20130023035A (ko) 리튬 이차 전지용 양극, 이를 포함하는 리튬 이차 전지
WO2014077225A1 (fr) Particules de matière active ainsi que procédé de fabrication de celles-ci, électrode positive pour dispositif de stockage d'électricité, et dispositif de stockage d'électricité
US20210118625A1 (en) Positive electrode for power storage device and power storage device
WO2019208733A1 (fr) Électrode positive pour dispositif de stockage d'énergie et dispositif de stockage d'énergie
WO2021039371A1 (fr) Couche de matériau actif pour électrode positive de dispositif de stockage d'énergie, électrode positive de dispositif de stockage d'énergie et dispositif de stockage d'énergie
WO2021039162A1 (fr) Matériau actif pour électrode positive de dispositif de stockage d'énergie, électrode positive pour dispositif de stockage d'énergie et dispositif de stockage d'énergie
WO2019208734A1 (fr) Électrode positive pour dispositifs de stockage d'électricité, et dispositif de stockage d'électricité
EP3817106A1 (fr) Matériau actif d'électrode positive, électrode positive, dispositif de stockage d'énergie et procédé de fabrication de matériau actif d'électrode positive
WO2019208735A1 (fr) Électrode positive de dispositifs de stockage d'électricité, et dispositif de stockage d'électricité
WO2020196747A1 (fr) Dispositif de stockage d'énergie et procédé de fabrication de dispositif de stockage d'énergie
KR20200081290A (ko) 코발트산 리튬 양극 활물질 및 이를 이용한 이차전지
WO2020195724A1 (fr) Matériau actif pour électrodes positives de dispositif de stockage d'électricité, électrode positive pour dispositifs de stockage d'électricité et dispositif de stockage d'électricité
KR102479724B1 (ko) 알콕시포스핀계 첨가제를 포함하는 리튬 이차전지
KR20240056447A (ko) 리튬 이차 전지용 전극의 제조방법 및 이로부터 제조된 전극과 상기 전극을 포함하는 리튬 이차 전지

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19793046

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2019793046

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2019793046

Country of ref document: EP

Effective date: 20201126