WO2011037254A1 - Électrode pour accumulateur, liant pour électrode d'accumulateur et accumulateur - Google Patents

Électrode pour accumulateur, liant pour électrode d'accumulateur et accumulateur Download PDF

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Publication number
WO2011037254A1
WO2011037254A1 PCT/JP2010/066817 JP2010066817W WO2011037254A1 WO 2011037254 A1 WO2011037254 A1 WO 2011037254A1 JP 2010066817 W JP2010066817 W JP 2010066817W WO 2011037254 A1 WO2011037254 A1 WO 2011037254A1
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Prior art keywords
electrode
secondary battery
segment
block copolymer
active material
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PCT/JP2010/066817
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English (en)
Japanese (ja)
Inventor
康尋 脇坂
庸介 薮内
重孝 早野
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日本ゼオン株式会社
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Priority to JP2011533076A priority Critical patent/JP5696664B2/ja
Priority to CN201080043137.5A priority patent/CN102549820B/zh
Publication of WO2011037254A1 publication Critical patent/WO2011037254A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • 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
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • 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 a secondary battery, a manufacturing method thereof, a binder constituting the electrode active material layer, and a battery using the electrode for the secondary battery.
  • Lithium ion secondary batteries show the highest energy density among practical batteries, and are widely used especially for small electronics. It is also expected to be used for automobile applications. Among them, there is a demand for further enhancement of performance, such as extending the life of lithium ion secondary batteries, operating in a wide temperature range, and improving safety.
  • the positive electrode of a lithium ion secondary battery is generally formed by bonding lithium-containing metal oxides such as LiCoO 2 , LiMn 2 O 4 and LiFePO 4 used as a positive electrode active material with a binder such as polyvinylidene fluoride. ing.
  • the negative electrode is formed by bonding a carbonaceous (amorphous) carbon material, metal oxide or metal sulfide, which is used as a negative electrode active material, with a binder such as a styrene-butadiene copolymer.
  • Patent Document 1 discloses the use of a styrene-butadiene-styrene block copolymer as a binder for an electrode composed of an active material and a binder in order to improve the performance of a lithium ion secondary battery.
  • a styrene-butadiene-styrene block copolymer By using a styrene-butadiene-styrene block copolymer, the detachment of the active material can be prevented, and a battery having a low internal resistance has been obtained.
  • Patent Document 2 discloses the use of a fluorine-containing block copolymer as a binder for an electrode comprising an active material and a binder.
  • a fluorine-containing block copolymer composed of a fluorine-containing segment and a non-fluorine segment an electrode having an excellent balance between adhesion to a current collector and resistance to electrolytic solution is obtained.
  • an object of the present invention is to provide an electrode for a secondary battery used for a lithium ion secondary battery or the like having further improved high temperature characteristics and long-term cycle characteristics.
  • the present inventors have determined that a polymer can be decomposed even at high temperatures by using a block copolymer containing no halogen atom and no unsaturated bond in the main chain as a binder. Therefore, the present inventors have found that the high-temperature characteristics and long-term cycle characteristics of the secondary battery using the secondary battery electrode having the block copolymer are improved, and the present invention has been completed.
  • a secondary battery in which a block copolymer containing no halogen atom and containing no unsaturated bond in the main chain and an electrode active material layer containing an electrode active material are laminated on a current collector.
  • An electrode is provided.
  • the block copolymer is preferably composed of a segment showing compatibility with the electrolytic solution and a segment showing no compatibility with the electrolytic solution. Due to the above structure of the block copolymer, dispersibility is improved due to high adsorption stability to the electrode active material, high electrolyte retention and electrolyte impregnation, and high output characteristics in addition to high long-term cycle characteristics. Can be shown.
  • Secondary battery electrode (3) The electrode for a secondary battery according to (1) or (2), wherein the block copolymer includes a segment of a soft polymer having a glass transition temperature of 15 ° C.
  • a binder for a secondary battery electrode comprising a block copolymer which does not contain a halogen atom and does not contain an unsaturated bond in the main chain.
  • the secondary battery electrode contains a specific binder
  • high dispersibility of the electrode active material and high electrolyte solution retention in the secondary battery electrode are achieved and obtained.
  • the high temperature characteristics and long-term cycle characteristics of the secondary battery are further improved.
  • An electrode for a secondary battery according to the present invention includes a current collector, a block copolymer provided on the current collector, which does not contain a halogen atom and does not contain an unsaturated bond in the main chain, and an electrode active material It has an active material layer.
  • the electrode active material layer of the present invention contains an electrode active material and a block copolymer. Hereinafter, this constituent material will be described in detail.
  • the electrode active material used for the secondary battery electrode of the present invention is generally selected according to the secondary battery in which the electrode is used.
  • Examples of the secondary battery include a lithium ion secondary battery and a nickel hydride secondary battery.
  • an active material capable of occluding and releasing lithium ions is used, and an electrode active material for a lithium ion secondary battery positive electrode (positive electrode active material) are roughly classified into those composed of inorganic compounds and those composed of organic compounds.
  • Examples of the positive electrode active material made of an inorganic compound include transition metal oxides, transition metal sulfides, lithium-containing composite metal oxides of lithium and transition metals, and the like.
  • Examples of the transition metal include Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Mo.
  • Transition metal oxides include MnO, MnO 2 , V 2 O 5 , V 6 O 13 , TiO 2 , Cu 2 V 2 O 3 , amorphous V 2 O—P 2 O 5 , MoO 3 , V 2 O. 5 , V 6 O 13 and the like. Among them, MnO, V 2 O 5 , V 6 O 13 and TiO 2 are preferable from the viewpoint of cycle stability and capacity of the obtained secondary battery.
  • the lithium-containing composite metal oxide include a lithium-containing composite metal oxide having a layered structure, a lithium-containing composite metal oxide having a spinel structure, and a lithium-containing composite metal oxide having an olivine structure.
  • lithium-containing composite metal oxide having a layered structure lithium-containing cobalt oxide (LiCoO 2 ), lithium-containing nickel oxide (LiNiO 2 ), Co—Ni—Mn lithium composite oxide, Ni—Mn—Al lithium
  • lithium-containing cobalt oxide (LiCoO 2 ) lithium-containing nickel oxide (LiNiO 2 ), Co—Ni—Mn lithium composite oxide, Ni—Mn—Al lithium
  • examples thereof include composite oxides and lithium composite oxides of Ni—Co—Al.
  • the lithium-containing composite metal oxide having a spinel structure include lithium manganate (LiMn 2 O 4 ) and Li [Mn 3/2 M 1/2 ] O 4 in which a part of Mn is substituted with another transition metal (wherein M may be Cr, Fe, Co, Ni, Cu or the like.
  • Li X MPO 4 (wherein, M is Mn, Fe, Co, Ni, Cu, Mg, Zn, V, Ca, Sr, Ba, Ti, Al, Li X MPO 4 as the lithium-containing composite metal oxide having an olivine structure)
  • An olivine type lithium phosphate compound represented by at least one selected from Si, B, and Mo, 0 ⁇ X ⁇ 2) may be mentioned.
  • An iron-based oxide having poor electrical conductivity may be used as an electrode active material covered with a carbon material by allowing a carbon source material to coexist during reduction firing. These compounds may be partially element-substituted.
  • organic compound for example, a conductive polymer such as polyacetylene or poly-p-phenylene can be used.
  • the positive electrode active material for a lithium ion secondary battery may be a mixture of the above inorganic compound and organic compound.
  • the particle diameter of the positive electrode active material is appropriately selected in consideration of other characteristics of the battery. From the viewpoint of improving battery characteristics such as load characteristics and cycle characteristics, the 50% volume cumulative diameter is usually 0.1 to It is 50 ⁇ m, preferably 1 to 20 ⁇ m. When the 50% volume cumulative diameter is within this range, a secondary battery having a large charge / discharge capacity can be obtained, and the electrode active material slurry and the electrode can be easily handled.
  • the 50% volume cumulative diameter can be determined by measuring the particle size distribution by laser diffraction.
  • examples of the electrode active material (negative electrode active material) for the lithium ion secondary battery negative electrode include amorphous carbon, graphite, natural graphite, Examples thereof include carbonaceous materials such as mesocarbon microbeads and pitch-based carbon fibers, and conductive polymers such as polyacene.
  • the simple substance which forms lithium alloys such as lithium metal, Ag, Al, Ba, Bi, Cu, Ga, Ge, In, Ni, P, Pb, Sb, Si, Sn, Sr, Zn Metals and alloys, and oxides and sulfides thereof are used.
  • Examples include lithium-containing metal composite oxide materials such as Li x Ti y M z O 4 containing a metal element selected from the group consisting of Pb and Ti atoms (0.7 ⁇ x ⁇ 1.5, 1.5 ⁇ y ⁇ 2.3, 0 ⁇ z ⁇ 1.6, M is Na, K, Co, Al, Fe, Ti, Mg, Cr, Ga, Cu, Zn, and Nb).
  • An electrode active material having a conductive agent attached to the surface by a mechanical modification method can also be used.
  • the particle size of the negative electrode active material is appropriately selected in consideration of other constituent elements of the battery. From the viewpoint of improving battery characteristics such as initial efficiency, load characteristics, and cycle characteristics, a 50% volume cumulative diameter is usually The thickness is 1 to 50 ⁇ m, preferably 15 to 30 ⁇ m.
  • the secondary battery electrode of the present invention is used for a nickel metal hydride secondary battery positive electrode
  • examples of the positive electrode active material that can be used include nickel hydroxide particles.
  • the nickel hydroxide particles may be dissolved in cobalt, zinc, cadmium, or the like, or may be coated with a cobalt compound whose surface is subjected to an alkali heat treatment.
  • the hydrogen storage alloy particles are used when charging the battery.
  • an electrode active material negative electrode active material
  • the hydrogen storage alloy particles are used when charging the battery.
  • the hydrogen storage alloy particles are preferred. Specifically, for example, LaNi 5 , MmNi 5 (Mm is a misch metal), LmNi 5 (Lm is at least one selected from rare earth elements including La), and a part of Ni of these alloys is Al, Mn, Co.
  • hydrogen storage alloy particles having a composition represented by the general formula: LmNi w Co x Mn y Al z (the total value of atomic ratios w, x, y, z is 4.80 ⁇ w + x + y + z ⁇ 5.40) Is preferable because pulverization with progress of the charge / discharge cycle is suppressed and charge / discharge cycle characteristics are improved.
  • electrode active materials for secondary batteries electrode active materials for lithium ion secondary batteries, which are most demanded for extending the life, operating in a wide temperature range, and improving safety, are preferable.
  • it is often used by increasing the energy density during electrode preparation and improving the energy density, and since the effect of suppressing the change in thickness after immersion is noticeable, an inorganic compound is preferable. preferable.
  • the binder of the present invention high conductivity can be exhibited even with a small amount of a conductive agent. Therefore, the lithium-containing composite metal oxide having a layered structure and the lithium-containing composite metal oxide having a spinel structure, which are used by using a small amount of a conductive agent without being too low in the active material, are most effective. Since it is obtained, it is preferable.
  • the content ratio of the electrode active material in the electrode active material layer is preferably 90 to 99.9% by mass, more preferably 95 to 99% by mass.
  • the electrode active material layer of the electrode for a secondary battery of the present invention contains a block copolymer that does not contain a halogen atom and does not contain an unsaturated bond in the main chain.
  • the block copolymer used in the present invention is preferably a block copolymer having two types of segments (segment A and segment B).
  • the block copolymer used in the present invention does not contain a halogen atom and does not contain an unsaturated bond in the main chain, the polymer is stabilized even at a high temperature, and side reactions such as decomposition of the polymer can be suppressed.
  • the high temperature characteristics, particularly high temperature cycle characteristics, of the battery electrode are greatly improved.
  • Halogen atoms not included in the block copolymer belong to Group 17 elements of the periodic table, and correspond to fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, and astatine atoms.
  • that the block copolymer does not contain a halogen atom means that the halogen content in the block copolymer is 100 ppm or less.
  • the halogen content is determined by combustion ion chromatography.
  • the block copolymer does not contain an unsaturated bond in the main chain.
  • the main chain is a polymer based on addition polymerization of C ⁇ C bonds, for example, the units — (CR 2 —CR 2 ) — (each R is independently a bond to a hydrogen atom or a side chain) are linked. Chain. Therefore, for example, a copolymer having units based on 1,4-addition polymerization of a conjugated diene such as isoprene or butadiene is not included in the copolymer having no unsaturated bond in the main chain in the present invention.
  • the block copolymer having no unsaturated bond in the main chain may have an iodine value of 10 mg / 100 mg or less. The iodine value is determined according to JISK0070 (1992).
  • the two segments of the block copolymer used in the present invention can be composed of various components as long as they do not contain a halogen atom and do not contain an unsaturated bond in the main chain.
  • one of the two types of segments is ethylene carbonate so that the electrode can have an electrolyte impregnation property and an electrolyte solution retention property, and further improve the dispersibility of the electrode active material.
  • the polymer is compatible with an electrolyte solution containing diethyl carbonate and the other segment is not compatible with the electrolyte solution.
  • segment A the former of the two types of segments will be referred to as segment A and the latter as segment B.
  • That the segment is compatible with the electrolytic solution means that the segment has a certain extent or more in the electrolytic solution, and can be determined by the degree of swelling of the segment with respect to the electrolytic solution.
  • compatibility means that the degree of swelling of the segment with respect to the electrolytic solution is 500% or more or dissolves in the electrolytic solution.
  • the fact that the segment does not exhibit compatibility with the electrolytic solution means that the spread of the segment in the electrolytic solution is not more than a certain value, and the degree of swelling of the segment with respect to the electrolytic solution is 0% or more and 300%. Indicates the following.
  • the degree of swelling of each segment is measured by the following method.
  • a polymer composed of the constituent components of segment A and a polymer composed of the constituent components of segment B are each formed into a film having a thickness of about 0.1 mm, cut into about 2 cm squares, and the weight (weight before immersion) is measured. .
  • it is immersed in the electrolyte solution at a temperature of 60 ° C. for 72 hours.
  • the soaked film is pulled up, the weight immediately after wiping off the electrolytic solution (weight after immersion) is measured, and the value of (weight after immersion) / (weight before immersion) ⁇ 100 (%) is defined as the degree of swelling.
  • a solution prepared by dissolving LiPF 6 at a concentration of 1 mol / liter in the mixed solvent is used.
  • the electrode active material and the conductive agent described later can be highly dispersed in the solvent in the electrode active material slurry described later.
  • the electrode when an electrode including a block copolymer having the above structure is used inside a battery, the electrode has a high electrolyte retention property for a long period of time, and further, elution of metal ions and oligomer components from the electrode is suppressed.
  • a secondary battery having an electrode exhibits high long-term cycle characteristics. Further, since the block copolymer forms a sea-island structure inside the electrode and has an appropriate swelling property to the electrolytic solution, the electrode exhibits high lithium conductivity, and the secondary battery having the electrode exhibits high output characteristics.
  • the block copolymer used in the present invention is an AB block structure composed only of the segment A and the segment B (here, the AB block structure is selected from the group consisting of AB type, ABA type, and BAB type structures) Or a structure containing other optional components.
  • these optional components may be coordinated at the end of the AB block structure or may be coordinated in the AB block structure.
  • the segment A includes a monomer component having a solubility parameter of 8.0 or more and less than 11 (unit: (cal / cm 3 ) 1/2 ) and / or a monomer component having a hydrophilic group. Is preferred. By including such a monomer component, the degree of swelling of the segment A with respect to the electrolytic solution can be controlled by the composition to provide a segment exhibiting compatibility with the electrolytic solution.
  • the term “monomer” or “monomer component” is understood to be a monomer constituting a monomer composition or constitutes a polymer depending on the context. It is understood that it is a polymerized unit based on a monomer.
  • Examples of monomers having a solubility parameter of 8.0 or more and less than 11 include alkenes such as ethylene and propylene; carbons of alkyl groups in ester groups such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, and pentyl methacrylate. 1 to 5 methacrylic acid alkyl esters; methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate and other ester groups such as alkyl acrylates having 1 to 5 carbon atoms; vinyl acetate, propion And vinyl esters such as vinyl acid vinyl, vinyl butyrate and vinyl benzoate.
  • alkenes such as ethylene and propylene
  • carbons of alkyl groups in ester groups such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, and pent
  • an acrylic acid alkyl ester or ester having an alkyl group with 1 to 5 carbon atoms in the ester group because it is highly compatible with the electrolyte and does not easily cause bridging aggregation due to the polymer in a small particle size dispersion.
  • a methacrylic acid alkyl ester having 1 to 5 carbon atoms in the alkyl group is more preferred.
  • alkyl acrylate or alkyl methacrylate examples include ester groups such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, and pentyl acrylate.
  • Acrylic acid alkyl ester having 1 to 5 carbon atoms in the alkyl group methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, and methacrylic acid Methacrylic acid alkyl ester in which the alkyl group in the ester group such as pentyl has 1 to 5 carbon atoms.
  • the solubility parameter (SP) in the segment A is 8.0.
  • the content of the monomer component that is less than 11 is preferably 30% by mass or more, and more preferably 50 to 90% by mass with respect to 100% by mass of the total amount of monomers used.
  • the content of the monomer component having a solubility parameter (SP) in segment A of 8.0 or more and less than 11 can be controlled by the monomer charge ratio at the time of producing the block polymer.
  • the solubility parameter (SP) is 8.0 or more and less than 11 and the content of the monomer component is within an appropriate range, so that it is compatible with the electrolyte solution but does not dissolve and elution inside the battery. Does not occur and exhibits high long-term cycle characteristics.
  • the solubility parameter of the polymer can be determined according to the method described in Polymer Handbook, but those not described in this publication can be determined according to the “molecular attractive constant method” proposed by Small.
  • the SP value ( ⁇ ) (cal / cm 3 ) 1 / is obtained from the characteristic value of the functional group (atomic group) constituting the compound molecule, that is, the statistics of the molecular attraction constant (G) and the molecular volume according to the following formula. This is a method for obtaining 2 .
  • V Specific volume
  • M Molecular weight d: Specific gravity
  • the monomer component having a hydrophilic group includes a monomer having a —COOH group (carboxylic acid group), a monomer having an —OH group (hydroxyl group), and a —SO 3 H group (sulfonic acid group).
  • Monomer having a monomer, a monomer having —PO 3 H 2 group, a monomer having —PO (OH) (OR) group (R represents a hydrocarbon group), and a lower polyoxyalkylene group The body is mentioned.
  • Examples of the monomer having a carboxylic acid group include monocarboxylic acid and derivatives thereof, dicarboxylic acid, acid anhydrides thereof, and derivatives thereof.
  • Examples of monocarboxylic acids include acrylic acid, methacrylic acid, and crotonic acid.
  • Examples of monocarboxylic acid derivatives include 2-ethylacrylic acid, 2-ethylacrylic acid, isocrotonic acid, ⁇ -acetoxyacrylic acid, ⁇ -trans-aryloxyacrylic acid, ⁇ -diaminoacrylic acid, and the like.
  • Examples of the dicarboxylic acid include maleic acid, fumaric acid, itaconic acid and the like.
  • Examples of the acid anhydride of dicarboxylic acid include maleic anhydride, acrylic anhydride, methyl maleic anhydride, and dimethyl maleic anhydride.
  • Examples of the dicarboxylic acid derivatives include methyl allyl maleate such as methylmaleic acid, dimethylmaleic acid, and phenylmaleic acid, diphenyl maleate, nonyl maleate, decyl maleate, dodecyl maleate, and octadecyl maleate; It is done.
  • Examples of the monomer having a hydroxyl group include ethylenically unsaturated alcohols such as (meth) allyl alcohol, 3-buten-1-ol and 5-hexen-1-ol; 2-hydroxyethyl acrylate, acrylic acid-2 Ethylene such as hydroxypropyl, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, di-2-hydroxyethyl maleate, di-4-hydroxybutyl maleate, di-2-hydroxypropyl itaconate Alkanol esters of the unsaturated unsaturated carboxylic acid; general formula CH 2 ⁇ CR 1 —COO— (C n H 2n O) m —H (m is an integer of 2 to 9, n is an integer of 2 to 4, and R 1 is An ester of a polyalkylene glycol represented by hydrogen or a methyl group and (meth) acrylic acid; 2-hydride Mono (meth) acrylic acid esters of dihydroxy esters of dicarboxylic acids such as
  • Examples of the monomer having a sulfonic acid group include vinyl sulfonic acid, methyl vinyl sulfonic acid, (meth) allyl sulfonic acid, styrene sulfonic acid, (meth) acrylic acid-2-ethyl sulfonate, 2-acrylamide-2. -Methylpropanesulfonic acid, 3-allyloxy-2-hydroxypropanesulfonic acid and the like.
  • Monomers having a —PO 3 H 2 group and / or —PO (OH) (OR) group include 2- (meth) acryloyloxyethyl phosphate, methyl phosphate -2- (Meth) acryloyloxyethyl, ethyl phosphate- (meth) acryloyloxyethyl, and the like.
  • Examples of the monomer containing a lower polyoxyalkylene group-containing group include poly (alkylene oxide) such as poly (ethylene oxide).
  • the segment A showing the compatibility with the electrolytic solution includes the monomer component unit having the hydrophilic group, among these monomers having the hydrophilic group, the electrode active material and the conductive agent described later are included. From the viewpoint of further improving dispersibility, a monomer having a carboxylic acid group is preferred.
  • the content of the monomer having a hydrophilic group in the segment A in the case where the segment A showing compatibility with the electrolytic solution contains a unit of the monomer component having the hydrophilic group is the total amount of monomers used Preferably it is 0.5-40 mass% with respect to 100 mass%, More preferably, it is the range of 3-20 mass%.
  • the content of the monomer having a hydrophilic group in the segment A can be controlled by the monomer charging ratio at the time of producing the block polymer. When the content of the monomer having a hydrophilic group in segment A is within a predetermined range, swelling to an appropriate electrolytic solution is exhibited, and elution inside the battery does not occur.
  • Segment A may have one of these monomer components alone, or may have two or more in combination.
  • the segment A may also contain a monomer copolymerizable with these monomers described later.
  • the segment B preferably includes a monomer component having a solubility parameter of less than 8.0 or 11 or more and / or a monomer component having a hydrophobic part.
  • a monomer component having a solubility parameter of less than 8.0 or 11 or more and / or a monomer component having a hydrophobic part By including such a monomer component, the degree of swelling of the segment B with respect to the electrolytic solution can be controlled by the composition, so that the segment does not exhibit compatibility with the electrolytic solution.
  • Examples of the monomer component having a solubility parameter of less than 8.0 or 11 or more include ⁇ , ⁇ -unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile.
  • the content of the components is preferably 30% by mass to 100% by mass, more preferably 50% by mass to 100% by mass, with respect to 100% by mass of the total amount of monomers used.
  • the content of the monomer component whose solubility parameter (SP) in segment B is less than 8.0 or 11 or more can be controlled by the monomer charge ratio at the time of block copolymer production.
  • Examples of monomer components having a hydrophobic part include styrene-based monomers such as styrene, ⁇ -styrene, vinyl toluene, t-butyl styrene, vinyl benzoic acid, methyl vinyl benzoate, vinyl naphthalene, ⁇ -methyl styrene, and divinyl benzene.
  • styrene-based monomers such as styrene, ⁇ -styrene, vinyl toluene, t-butyl styrene, vinyl benzoic acid, methyl vinyl benzoate, vinyl naphthalene, ⁇ -methyl styrene, and divinyl benzene.
  • the monomer component constituting the segment B that is not compatible with the electrolytic solution has low compatibility with the electrolytic solution, so that 2-ethylhexyl acrylate, nonyl acrylate, acrylate-decyl acrylate is used.
  • Alkyl acrylates having an alkyl group with 9 or more alkyl groups such as acrylate-lauryl, acrylate-n-tetradecyl, acrylate-stearyl, 2-ethylhexyl methacrylate, methacrylate-nonyl, methacrylate-decyl,
  • ⁇ does not show any swellability to the electrolyte.
  • ⁇ - unsaturated nitrile compound and styrene-based monomer is more preferable, and styrene monomer is most preferable.
  • segment B contains a monomer component unit having a hydrophobic part
  • the content of the monomer component having a hydrophobic part in segment B is preferably based on 100% by mass of the total amount of monomers used. Is 10% by mass or more and 100% by mass or less, more preferably 20% by mass or more and 100% by mass or less.
  • the content of the monomer component having a hydrophobic portion in the segment B can be controlled by the monomer charging ratio at the time of producing the block polymer. When the content of the monomer component having a hydrophobic portion in the segment B is in the above range, higher electrolyte solution resistance and long-term cycle characteristics are exhibited.
  • the content of the monomer component having a crosslinkable group in the segment B in the case where the segment B includes a monomer component unit having a crosslinkable group described later is based on 100% by mass of the total amount of monomers used. Preferably, it is 0.1 mass% or more and 10 mass% or less, More preferably, it is 0.1 mass% or more and 5 mass% or less.
  • the content of the monomer component having a crosslinkable group in the segment B can be controlled by the monomer charging ratio at the time of producing the block polymer. When the content of the monomer component having a crosslinkable group in the segment B is in the above range, a higher electrolytic solution resistance and long-term cycle characteristics are exhibited.
  • Segment B may have one of these monomer components alone, or may have two or more in combination.
  • the segment B may also contain a monomer copolymerizable with these monomers described later.
  • the block copolymer preferably contains a segment of a soft polymer having a glass transition temperature of 15 ° C. or lower.
  • the block polymer contains a segment of a soft polymer having a glass transition temperature of 15 ° C. or lower means that the block polymer of the present invention contains a segment constituting a soft polymer having a glass transition temperature of 15 ° C. or lower. Means that. Specifically, since at least one of segment A and segment B is the same segment as the segment constituting the soft polymer having a glass transition temperature of 15 ° C. or lower, an electrode having high flexibility can be obtained. Is preferred.
  • segment A when segment A shows compatibility with the electrolytic solution and segment B does not show compatibility with the electrolytic solution, segment A is the same segment as that constituting the soft polymer having a glass transition temperature of 15 ° C. or lower. Preferably, it is the same segment as the segment constituting the soft polymer having a glass transition temperature of ⁇ 5 ° C. or less, more preferably the segment constituting the soft polymer having a glass transition temperature of ⁇ 40 ° C. or less. Is the same segment.
  • the lower limit of the glass transition temperature is not particularly limited, but can be ⁇ 40 ° C. or higher.
  • segment A is the same segment as that constituting the soft polymer having a glass transition temperature within the above range, the mobility of segment A can be achieved while segment B in the block copolymer is adsorbed on the active material surface. Therefore, the lithium acceptability at low temperature is improved.
  • the glass transition temperature of a segment can be prepared by combining further the combination of the monomer illustrated above and the copolymerizable monomer mentioned later.
  • the ratio of segment A to segment B in the block copolymer is such that the composition of the block copolymer has a high output characteristic while having a long cycle characteristic while controlling the degree of swelling of the block copolymer in the electrolyte within a predetermined range.
  • the ratio of segment A to segment B is 10:90 to 90:10 (mass ratio), more preferably 30 when there is no copolymer component other than segment A and segment B. : 70 to 70:30 (mass ratio).
  • segment A methacrylic acid alkyl ester in which the alkyl group in the ester group such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, and pentyl methacrylate has 1 to 5 carbon atoms; monocarboxylic acid and its derivatives, A monomer having a carboxylic acid group such as dicarboxylic acid, its acid anhydride, and derivatives thereof includes styrene, ⁇ -styrene, vinyltoluene, t-butylstyrene, vinylbenzoic acid, methyl vinylbenzoate as segment B Styrene monomers such as vinyl naphthalene, ⁇ -methylstyrene, divinylbenzene; acrylic acid-hexyl, acrylic
  • methacrylic acid alkyl ester having 1 to 5 carbon atoms and segment B a combination of styrene is most preferable because of excellent dispersibility, load characteristics, and cycle characteristics.
  • the degree of swelling of the block copolymer with respect to the electrolytic solution tends to decrease as the molecular weight increases and increase as the molecular weight decreases. If the molecular weight is too small, dissolution in the electrolyte solution tends to occur. Accordingly, the range of the weight average molecular weight of the block polymer for achieving a suitable degree of swelling varies depending on the structure, the degree of crosslinking, and the like. For example, when there is no copolymer component other than segment A and segment B, tetrahydrofuran ( The standard polystyrene conversion value measured by gel permeation chromatography using THF as a developing solvent is 1,000 to 500,000, more preferably 5,000 to 100,000.
  • the weight average molecular weight of the block polymer When the weight average molecular weight of the block polymer is within the above range, the adsorption stability of the polymer to the active material is high, and the polymer does not cause cross-linking and aggregation, and exhibits excellent dispersibility. Further, the molecular weight distribution of the block copolymer represented by the ratio Mw / Mn between the weight average molecular weight Mw and the number average molecular weight Mn is preferably less than 2.0, more preferably 1.8 or less, particularly preferably 1.5. It is as follows. When the molecular weight distribution of the block copolymer is within the above range, the microphase separation structure becomes uniform and a stable strength can be obtained. The lower limit of the molecular weight distribution is not particularly limited, but can be 1.01 or more.
  • the degree of swelling of the block copolymer with respect to the electrolyte can be controlled by the degree of crosslinking.
  • the degree of swelling with respect to the electrolytic solution tends to decrease as the degree of crosslinking increases.
  • a preferable range of the degree of crosslinking is, for example, a degree of crosslinking that dissolves or swells to 400% or more when immersed in a polar solvent such as tetrahydrofuran for 24 hours.
  • Examples of the crosslinking method of the block copolymer include a method of crosslinking by heating or energy ray irradiation.
  • the degree of crosslinking can be adjusted by heating conditions or irradiation conditions (intensity, etc.) of energy beam irradiation. Further, since the degree of swelling tends to decrease as the degree of crosslinking increases, the degree of swelling can be adjusted by changing the degree of crosslinking.
  • the method of forming a block copolymer that can be crosslinked by heating or energy ray irradiation include a method of introducing a crosslinkable group into the block copolymer and a method of using a crosslinking agent in combination.
  • Examples of the method for introducing a crosslinkable group into the block copolymer include a method for introducing a photocrosslinkable crosslinkable group into the block copolymer and a method for introducing a heat crosslinkable crosslinkable group.
  • the method of introducing a heat-crosslinkable crosslinkable group into the block copolymer can crosslink the electrode by performing a heat treatment on the electrode after forming the electrode, and can further suppress dissolution in the electrolyte solution. This is preferable because a tough and flexible electrode can be obtained.
  • the thermally crosslinkable group is selected from the group consisting of an epoxy group, a hydroxyl group, an N-methylolamide group, an oxetanyl group, and an oxazoline group. At least one selected from the group consisting of epoxy groups is preferable, and an epoxy group is more preferable in terms of easy crosslinking and adjustment of the crosslinking density.
  • Examples of the monomer containing an epoxy group include a monomer containing a carbon-carbon double bond and an epoxy group.
  • Examples of the monomer containing a carbon-carbon double bond and an epoxy group include unsaturated glycidyl ethers such as vinyl glycidyl ether, allyl glycidyl ether, butenyl glycidyl ether, o-allylphenyl glycidyl ether; butadiene monoepoxide, Diene or polyene monoepoxides such as 4,5-epoxy-2-pentene, 3,4-epoxy-1-vinylcyclohexene, 1,2-epoxy-5,9-cyclododecadiene; 3,4-epoxy-1 Alkenyl epoxides such as butene, 1,2-epoxy-5-hexene, 1,2-epoxy-9-decene; glycidyl acrylate, glycidyl meth
  • Examples of the monomer containing an N-methylolamide group include (meth) acrylamides having a methylol group such as N-methylol (meth) acrylamide.
  • Monomers containing an oxetanyl group include 3-((meth) acryloyloxymethyl) oxetane, 3-((meth) acryloyloxymethyl) -2-trifluoromethyloxetane, and 3-((meth) acryloyloxymethyl). ) -2-phenyloxetane, 2-((meth) acryloyloxymethyl) oxetane, 2-((meth) acryloyloxymethyl) -4-trifluoromethyloxetane, and the like.
  • Monomers containing an oxazoline group include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2- Examples thereof include oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline and the like.
  • the content ratio of the heat-crosslinkable crosslinkable group in the block copolymer is preferably 0.00 with respect to 100% by mass of the total amount of monomers as the amount of the monomer containing the heat-crosslinkable crosslinkable group at the time of polymerization. It is in the range of 1 to 10% by mass, more preferably 0.1 to 5% by mass.
  • the content ratio of the heat-crosslinkable crosslinkable group in the block copolymer can be controlled by the monomer charge ratio when producing the block copolymer. When the content ratio of the thermally crosslinkable crosslinking group in the block copolymer is within the above range, elution into the electrolytic solution can be suppressed, and excellent electrode strength and long-term cycle characteristics can be exhibited.
  • the heat-crosslinkable crosslinkable group is a monomer containing a heat-crosslinkable crosslinkable group in addition to the above-mentioned monomers, and / or any copolymerizable with these monomers. It can introduce
  • the block copolymer used in the present invention may contain a monomer copolymerizable with these in addition to the monomer components described above.
  • Monomers copolymerizable with these include carboxylic acid esters having two or more carbon-carbon double bonds such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and trimethylolpropane triacrylate; methyl vinyl ether, ethyl vinyl ether Vinyl ethers such as butyl vinyl ether; vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, hexyl vinyl ketone, and isopropenyl vinyl ketone; heterocyclic-containing vinyl such as N-vinyl pyrrolidone, vinyl pyridine, and vinyl imidazole Compounds; amide monomers such as acrylamide and N-methylolacrylamide; By copolymerizing these monomers by an appropriate technique, the block polymer having the above-described structure
  • the block copolymer used in the present invention is not particularly limited with respect to the polymerization method as long as a block copolymer having segment A and segment B is obtained.
  • the monomer A is polymerized by a living polymerization method, and then the monomer B is added and polymerized without stopping the growth terminal of the obtained polymer to obtain a block copolymer. Can do.
  • monomer A and monomer B are separately synthesized by a living polymerization method, and polymer A and polymer B are preferably functional groups at their ends so that they can react and bond at the ends. Is introduced. Thereafter, A and B are mixed to obtain a block copolymer by coupling reaction, polyaddition and polycondensation.
  • a method of interfacial polycondensation or solution polycondensation of acid chloride and amine a method of polycondensation of amine-terminated polyamide and carboxylic acid-terminated polyamide in a molten state, and the like can be mentioned.
  • the monomer A is polymerized by a living polymerization method, and then a functional group is introduced into the living terminal to obtain a polymer A having a terminal functional group.
  • a block copolymer can be obtained by introducing a radical initiator into the obtained polymer A by a terminal group reaction and chain-polymerizing with the monomer B as a macroinitiator.
  • a radical initiator into the obtained polymer A by a terminal group reaction and chain-polymerizing with the monomer B as a macroinitiator.
  • a method of NCO conversion with an excess diisocyanate, t-butyl hydroperoxide bonded to the end, and then radical polymerization can be mentioned.
  • Living polymerization methods include various polymerization methods such as living anion polymerization, living cation polymerization, living coordination polymerization, and living radical polymerization. By using such a polymerization method, various vinyl monomers can be polymerized. Among them, living radical polymerization is preferable from the viewpoint of controlling the molecular weight and structure of the block copolymer and copolymerizing a monomer having a crosslinkable functional group.
  • Living polymerisation in the narrow sense, indicates that the terminal always has activity, but generally also includes pseudo-living polymerization where the terminal is inactive and the terminal is in equilibrium. It is.
  • the living radical polymerization in the present invention is a radical polymerization in which the polymerization end is activated and the inactivation is maintained in an equilibrium state, and has been actively studied in various groups in recent years.
  • Examples thereof include those using a chain transfer agent such as polysulfide, those using a cobalt porphyrin complex (Journal of American Chemical Society, 1994, 116, 7943) and radical scavengers such as nitroxide compounds (Macromolecules, 1994). 27, 7228), Inferter polymerization (Macromol. Chem. Rapid Commun., 3, 133 (1982)), which irradiates light on dithiocarbamate by Otsu et al.
  • a chain transfer agent such as polysulfide
  • those using a cobalt porphyrin complex Journal of American Chemical Society, 1994, 116, 7943
  • radical scavengers such as nitroxide compounds
  • RAFT atom transfer radical polymerization
  • a compound having the ester) structure reversible addition elimination chain transfer is used as a chain transfer agent (Reversible Addition-Fragmentation Chain Transfer: RAFT) can be mentioned polymerizing the like.
  • RAFT Reversible Addition-Fragmentation Chain Transfer
  • a stable nitroxy radical compound is used as the radical scavenger.
  • the stable nitroxy radical compound is not particularly limited, and includes known stable free radical agents, such as 2,2,5,5-substituted-1-pyrrolidinyloxy radicals, and other nitroxy groups derived from cyclic hydroxyamines. Free radicals are preferred.
  • an alkyl group having 4 or less carbon atoms such as a methyl group or an ethyl group is suitable.
  • nitroxy free radical compounds include, but are not limited to, 2,2,6,6-tetramethyl-1-piperidinyloxy radical (TEMPO), 2,2,6,6-tetraethyl-1- Piperidinyloxy radical, 2,2,6,6-tetramethyl-4-oxo-1-piperidinyloxy radical, 2,2,5,5-tetramethyl-1-pyrrolidinyloxy radical, 1, Examples include 1,3,3-tetramethyl-2-isoindolinyloxy radical, N, N-di-t-butylamineoxy radical, and the like. Of these, 2,2,6,6, -tetramethyl-1-piperidinyloxy and 4-oxo-2,2,6,6, -tetramethyl-1-piperidinyloxy are preferable. These may be used alone or in combination of two or more.
  • TEMPO 2,2,6,6-tetramethyl-1-piperidinyloxy radical
  • 2-piperidinyloxy radical 2,2,6,6-tetraethyl-1
  • a radical generator When using the above stable nitroxy radical compound, a radical generator is usually used.
  • the radical generator is not particularly limited as long as it generates radicals at the polymerization temperature, and a general thermal decomposition polymerization initiator can be used.
  • a general thermal decomposition polymerization initiator can be used.
  • azobisisobutyronitrile ( AIBN) azo compounds such as azobisisobutyric acid ester and hyponitrite
  • benzoyl peroxide (BPO) benzoyl peroxide (BPO), lauroyl peroxide, dicumyl peroxide, dibenzoyl peroxide and the like. These may be used alone or in combination of two or more.
  • an alkoxyamine compound may be used as an initiator.
  • a terminal functional group can be introduced by using an alkoxyamine having a functional group in the alkoxy group.
  • the polymerization is generally carried out at a polymerization temperature of about 50 to 170 ° C. A preferred temperature range is 70 to 160 ° C.
  • the reaction pressure is usually carried out at normal pressure, but it can also be carried out under pressure.
  • a chain transfer agent or a terminating agent having a target functional group in the molecule for example, a chain transfer agent or a terminating agent having a target functional group in the molecule And the like.
  • the chain transfer agent or terminator having the functional group in the molecule is not particularly limited.
  • a hydroxyl group is introduced by mercaptoethanol, mercaptopropanol, mercaptobutanol, 2,2′-dithioethanol, etc., and 2-mercaptoacetic acid is introduced.
  • 2-mercaptopropionic acid, dithioglycolic acid, 3,3′-dithiopropionic acid, 2,2′-dithiobenzoic acid and the like introduce a carboxyl group
  • 3-mercaptopropylmethyldimethoxysilane introduces a silyl group
  • RAFT polymerization When reversible addition / elimination chain transfer polymerization (RAFT polymerization) is used as the living polymerization, a sulfur compound such as dithioester, trithiocarbamate, xanthate or dithiocarbamate is started as a chain transfer agent (and also serves as an initiator). Polymerization is performed as an agent.
  • RAFT polymerization reversible addition / elimination chain transfer polymerization
  • an additional radical initiator for polymerization particularly an initiator further comprising an azo or peroxo initiator that decomposes by heat to generate radicals.
  • azo compounds such as azobisisobutyronitrile (AIBN), azobisisobutyric acid ester, hyponitrite; benzoyl peroxide (BPO), lauroyl peroxide, dicumyl peroxide, dibenzoyl peroxide, and the like. These may be used alone or in combination of two or more.
  • the living polymerization in the present invention can be carried out by solvent polymerization (bulk polymerization), solution polymerization in an organic solvent (for example, toluene), emulsion polymerization or suspension polymerization.
  • solvent polymerization bulk polymerization
  • solution polymerization in an organic solvent for example, toluene
  • emulsion polymerization emulsion polymerization or suspension polymerization.
  • Each stage of the polymerization process can be performed in a “batch” process (ie, a discontinuous process) in the same reactor, or in a semi-continuous or continuous process in separate reactors.
  • examples of the solvent used include, but are not limited to, the following solvents.
  • hydrocarbon solvents such as hexane and octane
  • ester solvents such as ethyl acetate and n-butyl acetate
  • ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone
  • alcohol solvents such as methanol, ethanol and isopropanol
  • tetrahydrofuran And ether solvents such as diethyl ether, dioxane and ethylene glycol dimethyl ether
  • amide solvents such as dimethylformamide and dimethylacetamide
  • aromatic petroleum solvents such as toluene, xylene and benzene.
  • the type and amount of the solvent used are the solubility of the monomer used, the solubility of the resulting polymer, the polymerization initiator concentration and monomer concentration appropriate for achieving a sufficient reaction rate, the solubility of the sulfur compound, It may be determined in consideration of the influence on human body and environment, availability, price, etc., and is not particularly limited. Among them, in terms of solubility, availability, and price, industrially, toluene, dimethylformamide, tetrahydrofuran, and acetone are preferable, and toluene and dimethylformamide are more preferable.
  • the emulsifier used includes, but is not limited to, the following emulsifiers.
  • Anionic surfactants such as sodium, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate; polyoxyethylene alkyl ether, polyoxyethylene higher alcohol ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, Polyoxyethylene sorbitol fatty acid ester,
  • emulsifiers may be used alone or in combination. If necessary, a dispersant for suspension polymerization described later may be added.
  • the amount of the emulsifier used is not particularly limited, but is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the monomer from the viewpoint that the emulsified state is good and the polymerization proceeds smoothly.
  • anionic surfactants and nonionic surfactants are preferred in terms of stability in the emulsified state.
  • any of the commonly used dispersants can be used as the dispersant.
  • the following dispersants can be mentioned, but are not limited thereto.
  • examples thereof include partially saponified polyvinyl acetate, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, gelatin, and polyalkylene oxide. These may be used alone or in combination.
  • an emulsifier used in the emulsion polymerization may be used in combination.
  • the amount of the dispersant to be used is not particularly limited, but is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the monomer used from the viewpoint that the polymerization proceeds smoothly.
  • the block copolymer used in the present invention is preferably obtained through a particulate metal removal step of removing particulate metal contained in the polymer solution or polymer dispersion in the block copolymer production process.
  • a particulate metal removal step of removing particulate metal contained in the polymer solution or polymer dispersion in the block copolymer production process.
  • the method for removing the particulate metal component from the polymer solution or polymer dispersion in the particulate metal removal step is not particularly limited.
  • Examples thereof include a removal method and a removal method using magnetic force.
  • the removal object is a metal component
  • the method of removing by magnetic force is preferable.
  • the method for removing by magnetic force is not particularly limited as long as it is a method capable of removing a metal component. However, in consideration of productivity and removal efficiency, it is preferably performed by placing a magnetic filter in the block copolymer production line. .
  • the content ratio of the block copolymer in the secondary battery electrode is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass with respect to 100 parts by mass of the active material.
  • the content of the block copolymer in the secondary battery electrode is within the above range, the binding of the active material to each other and the current collector is excellent, while maintaining flexibility and inhibiting the movement of Li. The resistance does not increase.
  • the current collector used for the secondary battery electrode of the present invention is not particularly limited as long as it has electrical conductivity and is electrochemically durable, but from the viewpoint of having heat resistance, for example, Metal materials such as iron, copper, aluminum, nickel, stainless steel, titanium, tantalum, gold, and platinum are preferable. Among these, aluminum is particularly preferable for the positive electrode of the lithium ion secondary battery.
  • the shape of the current collector is not particularly limited, but a sheet shape having a thickness of about 0.001 to 0.5 mm is preferable. In order to increase the adhesive strength of the electrode active material layer, the current collector is preferably used after roughening in advance.
  • Examples of the roughening method include a mechanical polishing method, an electrolytic polishing method, and a chemical polishing method.
  • a mechanical polishing method an abrasive cloth paper with a fixed abrasive particle, a grindstone, an emery buff, a wire brush provided with a steel wire or the like is used.
  • an intermediate layer may be formed on the surface of the current collector in order to increase the adhesive strength and conductivity of the electrode active material layer.
  • the electrode for a secondary battery of the present invention is further added with an electrolytic solution having functions such as a conductive agent, a reinforcing material, a dispersing agent, a leveling agent, an antioxidant, a thickener, and an electrolytic decomposition inhibition.
  • an electrolytic solution having functions such as a conductive agent, a reinforcing material, a dispersing agent, a leveling agent, an antioxidant, a thickener, and an electrolytic decomposition inhibition.
  • Arbitrary components such as a binder other than an agent and a block copolymer, may be contained, and may be contained in the electrode active material slurry mentioned later. These are not particularly limited as long as they do not affect the battery reaction.
  • conductive carbon such as acetylene black, ketjen black, carbon black, graphite, vapor-grown carbon fiber, and carbon nanotube
  • examples thereof include carbon powder such as graphite, fibers and foils of various metals.
  • the conductivity imparting material By using the conductivity imparting material, the electrical contact between the electrode active materials can be improved. In particular, when used in a lithium ion secondary battery, the discharge load characteristics can be improved.
  • the reinforcing material various inorganic and organic spherical, plate-like, rod-like or fibrous fillers can be used. By using a reinforcing material, a tough and flexible electrode can be obtained, and excellent long-term cycle characteristics can be exhibited.
  • the amount of the conductivity-imparting material and the reinforcing agent used is usually 0.01 to 20 parts by mass, preferably 1 to 10 parts by mass with respect to 100 parts by mass of the electrode active material. By being included in the said range, a high capacity
  • the dispersant examples include anionic compounds, cationic compounds, nonionic compounds, and polymer compounds.
  • a dispersing agent is selected according to the electrode active material and electrically conductive agent to be used.
  • the content of the dispersant in the electrode is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material.
  • the leveling agent examples include surfactants such as alkyl surfactants, silicon surfactants, fluorine surfactants, and metal surfactants. By mixing the surfactant, it is possible to prevent repelling that occurs during coating or to improve the smoothness of the electrode.
  • the content of the leveling agent in the electrode is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material. When the leveling agent is within the above range, the productivity, smoothness, and battery characteristics during electrode production are excellent.
  • the antioxidant examples include a phenol compound, a hydroquinone compound, an organic phosphorus compound, a sulfur compound, a phenylenediamine compound, and a polymer type phenol compound.
  • the polymer type phenol compound is a polymer having a phenol structure in the molecule, and a polymer type phenol compound having a weight average molecular weight of 200 to 1000, preferably 600 to 700 is preferably used.
  • the content ratio of the antioxidant in the electrode active material layer is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the electrode active material. When the antioxidant is in the above range, the slurry stability, battery capacity and cycle characteristics are excellent.
  • thickeners include cellulose polymers such as carboxymethylcellulose, methylcellulose, hydroxypropylcellulose, and ammonium salts and alkali metal salts thereof; (modified) poly (meth) acrylic acid and ammonium salts and alkali metal salts thereof; ) Polyvinyl alcohols such as polyvinyl alcohol, copolymers of acrylic acid or acrylate and vinyl alcohol, maleic anhydride or copolymers of maleic acid or fumaric acid and vinyl alcohol; polyethylene glycol, polyethylene oxide, polyvinyl pyrrolidone, modified Polyacrylic acid, oxidized starch, phosphoric acid starch, casein, various modified starches, acrylonitrile-butadiene copolymer hydride, and the like.
  • cellulose polymers such as carboxymethylcellulose, methylcellulose, hydroxypropylcellulose, and ammonium salts and alkali metal salts thereof; (modified) poly (meth) acrylic acid and ammonium salts and alkali metal salts thereof
  • (modified) poly means “unmodified poly” or “modified poly”
  • (meth) acryl means “acryl” or “methacryl”.
  • the content ratio of the thickener in the electrode active material layer is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material.
  • the electrolytic solution additive vinylene carbonate used in an electrode active material slurry and an electrolytic solution described later can be used.
  • the content ratio of the electrolytic solution additive in the electrode active material layer is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material.
  • the electrolytic solution additive is in the above range, the cycle characteristics and the high temperature characteristics are excellent.
  • Other examples include nano-particles such as fumed silica and fumed alumina: surfactants such as alkyl surfactants, silicon surfactants, fluorine surfactants, and metal surfactants.
  • the content ratio of nanoparticles and the like in the electrode active material layer is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material. When the nanoparticles are in the above range, the slurry stability and productivity are excellent, and high battery characteristics are exhibited.
  • the content ratio of the surfactant in the electrode active material layer is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the electrode active material. When the surfactant is in the above range, the slurry stability and electrode smoothness are excellent, and high productivity is exhibited.
  • the binder may further contain an optional binder component in addition to the block polymer.
  • an optional binder component various resin components can be used in combination.
  • polyethylene, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyacrylic acid, polyacrylonitrile, polyacrylate, polymethacrylate, or the like may be used. it can. Copolymers containing 50% or more of the above resin components can also be used.
  • polyacrylic acid derivatives such as acrylic acid-styrene copolymers and acrylic acid-acrylate copolymers, acrylonitrile-styrene copolymers, acrylonitrile-acrylates.
  • Polyacrylonitrile derivatives such as copolymers can also be used.
  • the soft polymer illustrated below can also be used as a binder.
  • Acrylic acid such as polybutyl acrylate, polybutyl methacrylate, polyhydroxyethyl methacrylate, polyacrylamide, polyacrylonitrile, butyl acrylate / styrene copolymer, butyl acrylate / acrylonitrile copolymer, butyl acrylate / acrylonitrile / glycidyl methacrylate copolymer
  • an acrylic soft polymer which is a homopolymer of a methacrylic acid derivative or a copolymer with a monomer copolymerizable therewith; a silicon-containing soft polymer such as dimethylpolysiloxane, diphenylpolysiloxane, dihydroxypolysiloxane; Liquid polyethylene, polypropylene, poly-1-butene, ethylene / ⁇ -olefin copolymer, propylene / ⁇ -olefin copolymer, ethylene / propylene
  • the thickness of the electrode for a secondary battery of the present invention is usually 5 to 300 ⁇ m, preferably 10 to 250 ⁇ m. When the electrode thickness is in the above range, both load characteristics and energy density are high.
  • the electrode for a secondary battery of the present invention is produced by a method of laminating an electrode active material layer on at least one surface, preferably both surfaces of the current collector.
  • the constituent material of the said electrode active material layer is mixed with a solvent, electrode active material slurry is adjusted, electrode active material slurry is apply
  • the manufacturing method of the electrode active material slurry, the manufacturing method of an electrode active material slurry, and the electrode for secondary batteries is demonstrated. Note that the current collector, electrode active material, block copolymer, and other components contained in the secondary battery electrode are the same as described above, and thus the description thereof is omitted here.
  • the secondary battery electrode active material slurry used in the present invention contains an electrode active material, a block polymer, other components and a solvent.
  • the solvent is not particularly limited as long as it can uniformly dissolve or disperse the block polymer of the present invention.
  • a solvent used for the electrode active material slurry either water or an organic solvent can be used.
  • organic solvents examples include cycloaliphatic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; acetone, ethyl methyl ketone, disopropyl ketone, cyclohexanone, methylcyclohexane, and ethylcyclohexane.
  • Ketones such as ethyl acetate, butyl acetate, ⁇ -butyrolactone, and ⁇ -caprolactone; acylonitriles such as acetonitrile and propionitrile; ethers such as tetrahydrofuran and ethylene glycol diethyl ether: methanol, ethanol, isopropanol, and ethylene And alcohols such as glycol and ethylene glycol monomethyl ether; amides such as N-methylpyrrolidone and N, N-dimethylformamide. These solvents may be used alone, or two or more of these may be mixed and used as a mixed solvent.
  • a solvent having excellent solubility of the polymer of the present invention, excellent dispersibility of the electrode active material and the conductive agent, and having a low boiling point and high volatility is preferable because it can be removed at a low temperature in a short time.
  • Acetone, toluene, cyclohexanone, cyclopentane, tetrahydrofuran, cyclohexane, xylene, water, N-methylpyrrolidone, or a mixed solvent thereof is preferable.
  • the solid content concentration of the electrode active material slurry used in the present invention is not particularly limited as long as it can be applied and immersed and has a fluid viscosity, but is generally about 10 to 80% by mass. .
  • an electrode active material slurry is not specifically limited, A block polymer, an electrode active material, a solvent, and the arbitrary containing component added as needed are mixed and obtained.
  • an electrode active material slurry in which the electrode active material and the conductive agent are highly dispersed can be obtained regardless of the mixing method and mixing order by using the above components.
  • the mixing device is not particularly limited as long as it can uniformly mix the above-mentioned components. Bead mill, ball mill, roll mill, sand mill, pigment disperser, crusher, ultrasonic disperser, homogenizer, planetary mixer, fill mix, etc.
  • the viscosity of the electrode active material slurry is preferably 10 mPa ⁇ s to 100,000 mPa ⁇ s, more preferably 100 to 50,000 mPa ⁇ s, from the viewpoints of uniform coatability and slurry aging stability.
  • the viscosity is a value measured using a B-type viscometer at 25 ° C. and a rotation speed of 60 rpm.
  • the manufacturing method of the electrode for secondary batteries of this invention should just be a method of laminating
  • the manufacturing method including the step of applying the electrode active material slurry to one surface of the current collector and the step of drying may be mentioned.
  • the method for applying the electrode active material slurry to the current collector is not particularly limited. Examples thereof include a doctor blade method, a zip method, a reverse roll method, a direct roll method, a gravure method, an extrusion method, and a brush coating method. Examples of the drying method include drying by warm air, hot air, low-humidity air, vacuum drying, and drying by irradiation with (far) infrared rays or electron beams.
  • the porosity of the electrode it is preferable to lower the porosity of the electrode by pressure treatment using a mold press or a roll press.
  • a preferable range of the porosity is 5% to 15%, more preferably 7% to 13%. If the porosity is too high, charging efficiency and discharging efficiency are deteriorated. When the porosity is too low, it is difficult to obtain a high volume capacity, and the electrodes are liable to peel off and cause defects. Further, when a curable polymer is used, it is preferably cured.
  • the present invention is also a secondary battery configured using the above-described secondary battery electrode or the above secondary battery electrode.
  • the configuration of the electrode according to the present invention can be applied to both a stacked battery and a bipolar battery. Below, the structure of the secondary battery of this invention is demonstrated.
  • the secondary battery of this invention has a positive electrode, electrolyte solution, a separator, and a negative electrode, and the said positive electrode and / or a negative electrode are the electrodes for secondary batteries of this invention.
  • Examples of the secondary battery include a lithium ion secondary battery and a nickel hydride secondary battery. However, since the most demanded improvement in performance such as long-term cycle characteristics and wide operating temperature range, lithium ion secondary batteries can be used. Secondary batteries are preferred. Hereinafter, the case where it uses for a lithium ion secondary battery is demonstrated.
  • Electrode for lithium ion secondary battery As the electrolytic solution for the lithium ion secondary battery, an organic electrolytic solution in which a supporting electrolyte is dissolved in an organic solvent is used. A lithium salt is used as the supporting electrolyte.
  • the lithium salt is not particularly limited, LiPF 6, LiAsF 6, LiBF 4, LiSbF 6, LiAlCl 4, LiClO 4, CF 3 SO 3 Li, C 4 F 9 SO 3 Li, CF 3 COOLi, (CF 3 CO) 2 NLi, (CF 3 SO 2 ) 2 NLi, (C 2 F 5 SO 2 ) NLi, and the like.
  • LiPF 6 , LiClO 4 , and CF 3 SO 3 Li that are easily soluble in a solvent and exhibit a high degree of dissociation are preferable. Two or more of these may be used in combination. Since the lithium ion conductivity increases as the supporting electrolyte having a higher degree of dissociation is used, the lithium ion conductivity can be adjusted depending on the type of the supporting electrolyte.
  • the organic solvent used in the electrolyte for the lithium ion secondary battery is not particularly limited as long as it can dissolve the supporting electrolyte, but dimethyl carbonate (DMC), ethylene carbonate (EC), diethyl carbonate (DEC), propylene Carbonates such as carbonate (PC), butylene carbonate (BC) and methyl ethyl carbonate (MEC); esters such as ⁇ -butyrolactone and methyl formate; ethers such as 1,2-dimethoxyethane and tetrahydrofuran; sulfolane and dimethyl sulfoxide Sulfur-containing compounds such as are preferably used. Moreover, you may use the liquid mixture of these solvents.
  • DMC dimethyl carbonate
  • EC ethylene carbonate
  • DEC diethyl carbonate
  • PC butylene carbonate
  • MEC methyl ethyl carbonate
  • esters such as ⁇ -butyrolactone and methyl formate
  • ethers such as 1,2-d
  • carbonates are preferable because they have a high dielectric constant and a wide stable potential region. Since the lithium ion conductivity increases as the viscosity of the solvent used decreases, the lithium ion conductivity can be adjusted depending on the type of the solvent. Moreover, it is also possible to use the electrolyte solution by containing an additive. Examples of the additive include carbonate compounds such as vinylene carbonate (VC) used in the above-mentioned electrode active material slurry.
  • VC vinylene carbonate
  • the concentration of the supporting electrolyte in the electrolytic solution for the lithium ion secondary battery is usually 1 to 30% by mass, preferably 5 to 20% by mass.
  • the concentration is usually 0.5 to 2.5 mol / L depending on the type of the supporting electrolyte. If the concentration of the supporting electrolyte is too low or too high, the ionic conductivity tends to decrease.
  • the electrolytic solution other than the above include polymer electrolytes such as polyethylene oxide and polyacrylonitrile, gelled polymer electrolytes in which the polymer electrolyte is impregnated with an electrolytic solution, and inorganic solid electrolytes such as LiI and Li 3 N.
  • Separator for lithium ion secondary battery As a separator for a lithium ion secondary battery, known ones such as a microporous film or nonwoven fabric containing a polyolefin resin such as polyethylene or polypropylene or an aromatic polyamide resin; a porous resin coat containing an inorganic ceramic powder; .
  • polyolefin films polyethylene, polypropylene, polybutene, polyvinyl chloride
  • porous membranes made of resins such as mixtures or copolymers thereof, polyethylene terephthalate, polycycloolefin, polyethersulfone, polyamide, polyimide, polyimideamide, polyaramid And a microporous membrane made of a resin such as polycycloolefin, nylon, and polytetrafluoroethylene, or a woven fabric of polyolefin fibers, a nonwoven fabric thereof, an aggregate of insulating substance particles, or the like.
  • a microporous film made of a polyolefin-based resin is preferable because the thickness of the entire separator can be reduced and the active material ratio in the battery can be increased to increase the capacity per volume.
  • the thickness of the separator is usually 0.5 to 40 ⁇ m, preferably 1 to 30 ⁇ m, more preferably 1 to 10 ⁇ m. Within this range, the resistance due to the separator in the battery is reduced, and the workability during battery production is excellent.
  • a positive electrode and a negative electrode are overlapped via a separator, and this is wound into a battery container according to the shape of the battery.
  • the method of injecting and sealing is mentioned. If necessary, an expanded metal, an overcurrent prevention element such as a fuse or a PTC element, a lead plate, or the like can be inserted to prevent an increase in pressure inside the battery and overcharge / discharge.
  • the shape of the battery may be any of a coin shape, a button shape, a sheet shape, a cylindrical shape, a square shape, a flat shape, and the like.
  • cycle characteristics The obtained full-cell coin-type battery was charged at 3 ° C to 4.3V at 0.1C at 25 ° C, and then charged / discharged from 4.3V to 3V at 0.1C for 100 cycles.
  • ⁇ Battery characteristics High temperature characteristics> The obtained full-cell coin-type battery was charged from 3 V to 4.3 V at 0.1 C at 60 ° C., and then charged and discharged to discharge from 4.3 V to 3 V at 0.1 C for 20 cycles. A value obtained by calculating the percentage of the 0.1C discharge capacity at the 20th cycle with respect to the 0.1C discharge capacity as a percentage was determined as the capacity maintenance rate, and was determined according to the following criteria. The larger this value, the less the discharge capacity is reduced, and the higher temperature characteristics are better. A: 70% or more B: 60% or more and less than 70% C: 50% or more and less than 60% D: 40% or more and less than 50% E: 30% or more and less than 40% F: Less than 30%
  • ⁇ Battery characteristics low temperature characteristics>
  • the obtained full cell coin type battery is charged at a constant current until it reaches 4.3 V by a constant current constant voltage charging method at 25 ° C. with a charge / discharge rate of 0.1 C, and is charged at a constant voltage.
  • the battery is discharged at 0.1 C to 3.0 V, and the discharge capacity at 25 ° C. is obtained.
  • constant current and constant voltage charging was performed at 0.1 C in a thermostat set to ⁇ 20 ° C.
  • the battery capacity at 25 ° C. is a
  • the battery capacity at ⁇ 20 ° C. is b.
  • Example 1 Synthesis of block copolymer> To a four-necked flask equipped with a mechanical stirrer, nitrogen inlet, cooling tube and rubber septum, 100 parts of toluene and 40 parts of styrene were added, and 1.3 parts of 2,2′-bipyridine was added thereto. Then, the inside of the system was replaced with nitrogen. To this was added 0.41 part of copper bromide under a nitrogen stream, the reaction system was heated to 90 ° C., and 0.21 part of 2-hydroxyethyl 2-bromo-2-methylpropionate was added as an initiator. Then, polymerization was started, and polymerization was performed at 90 ° C. for 9 hours under a nitrogen stream.
  • the polymerization rate (the ratio defined by the value obtained by dividing the weight of the polymer after heating and removing the volatile component by the weight of the polymer as it was before removing the volatile component) is 90% or more.
  • the polymerization rate is 90% or more.
  • 60 parts of n-butyl acrylate from a rubber septum which was further heated at 110 ° C. for 12 hours.
  • a toluene solution of a block copolymer of styrene-butyl acrylate was obtained.
  • the obtained block copolymer solution was placed in an autoclave equipped with a stirrer.
  • the molecular weight distribution (Mw / Mn) was 1.2 to 1.3.
  • the composition, ratio, weight average molecular weight, and glass transition temperature of the obtained polymer-1 are shown in Table 1.
  • the glass transition temperature was measured by differential scanning calorimetry (DSC method, manufactured by Seiko Instruments Inc., product name “EXSTAR6000”) from ⁇ 120 ° C. to 120 ° C. at a rate of temperature increase of 20 ° C./min. .
  • the weight average molecular weight was determined by dissolving polymer-1 in tetrahydrofuran to give a 0.2 wt% solution, followed by filtration with a 0.45 ⁇ m membrane filter, and using gel permeation chromatography (GPC) as a measurement sample.
  • GPC gel permeation chromatography
  • NMP N-methyl-2-pyrrolidone
  • a slurry-like electrode composition for negative electrode (slurry for forming a negative electrode active material layer) was prepared by mixing with a planetary mixer. This negative electrode composition was applied to one side of a 10 ⁇ m thick copper foil, dried at 110 ° C. for 3 hours, and then roll pressed to obtain a negative electrode having a negative active material layer having a thickness of 60 ⁇ m.
  • Electrode composition for positive electrode and positive electrode Add 92 parts of lithium manganate having a spinel structure as the positive electrode active material, 5 parts of acetylene black, 3 parts of NMP solution of polymer-1 as the binder, and adjust the solid content concentration to 87% with NMP. And then mixed for 60 minutes with a planetary mixer. Furthermore, after adjusting to solid content concentration 84% with NMP, it mixed for 10 minutes and prepared the electrode composition for positive electrodes for positive electrodes (positive electrode active material slurry). This positive electrode composition was applied to an aluminum foil having a thickness of 18 ⁇ m, dried at 120 ° C. for 3 hours, and then roll-pressed to obtain a positive electrode having a positive electrode active material layer having a thickness of 50 ⁇ m.
  • the obtained positive electrode was cut out into a circle having a diameter of 13 mm.
  • the obtained negative electrode was cut into a circle having a diameter of 14 mm.
  • a single-layer polypropylene separator (porosity 55%) manufactured by a dry method having a thickness of 25 ⁇ m was cut into a circle having a diameter of 18 mm. These were housed in a stainless steel coin-type outer container (diameter 20 mm, height 1.8 mm, stainless steel thickness 0.25 mm) provided with polypropylene packing.
  • the arrangement of the circular electrodes and separators in the outer container was as follows. The circular positive electrode was disposed so that the aluminum foil was in contact with the bottom surface of the outer container.
  • the circular separator was disposed so as to be interposed between the circular positive electrode and the circular negative electrode with a porous film.
  • a 0.2 mm thick stainless steel cap was placed on the container and fixed, and the battery can was sealed to produce a full cell coin cell having a diameter of 20 mm and a thickness of about 3.2 mm (coin cell CR2032).
  • the obtained battery was measured for output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics. The results are shown in Table 2.
  • Example 2 The positive electrode active material slurry, the positive electrode, and the positive electrode active material slurry, except that Polymers 2 to 5 having the composition and weight average molecular weight shown in Table 1 were used in place of Polymer-1 as a binder constituting the positive electrode. A battery was produced. Then, the output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics of the obtained batteries were evaluated. The results are shown in Table 2.
  • the molecular weight distributions (Mw / Mn) of the polymers 2 to 5 were all 1.2 to 1.3.
  • Example 6 The time of polymerization reaction at 90 ° C. after adding styrene and other substances (initiator, etc.) to the flask was changed from 9 hours to 36 hours, and after addition of n-butyl acrylate to the reaction mixture, it was changed to 110 ° C.
  • a block polymer was synthesized in the same manner as in Example 1 except that the heating time was changed from 12 hours to 48 hours to obtain a polymer-6.
  • the composition, ratio, weight average molecular weight, and glass transition temperature of the obtained polymer-6 are shown in Table 1.
  • the molecular weight distribution (Mw / Mn) of the polymer 6 was 1.2 to 1.3.
  • a positive electrode active material slurry, a positive electrode, and a battery were prepared in the same manner as in Example 1 except that polymer-6 was used instead of polymer-1 as a binder constituting the positive electrode. Then, the output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics of the obtained batteries were evaluated. The results are shown in Table 2.
  • Example 7 The time for the polymerization reaction at 90 ° C. after adding styrene and other substances (initiator, etc.) to the flask was changed from 9 hours to 1 hour, to 110 ° C. after adding n-butyl acrylate to the reaction mixture.
  • a block polymer was synthesized in the same manner as in Example 1 except that the heating time was changed from 12 hours to 2 hours to obtain a polymer-7.
  • the composition, ratio, weight average molecular weight, and glass transition temperature of the obtained polymer-7 are shown in Table 1.
  • the molecular weight distribution (Mw / Mn) of the polymer 7 was 1.2 to 1.3.
  • a positive electrode active material slurry, a positive electrode, and a battery were prepared in the same manner as in Example 1 except that Polymer-7 was used instead of Polymer-1 as a binder constituting the positive electrode. Then, the output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics of the obtained batteries were evaluated. The results are shown in Table 2.
  • Example 8 To a four-necked flask equipped with a mechanical stirrer, nitrogen inlet, cooling tube and rubber septum, 100 parts of toluene and 40 parts of styrene were added, and 1.3 parts of 2,2′-bipyridine was added thereto. Then, the inside of the system was replaced with nitrogen. To this was added 0.41 part of copper bromide under a nitrogen stream, the reaction system was heated to 90 ° C., and 0.21 part of 2-hydroxyethyl 2-bromo-2-methylpropionate was added as an initiator. Then, polymerization was started, and polymerization was performed at 90 ° C. for 3 hours under a nitrogen stream.
  • the polymerization rate (the ratio defined by the value obtained by dividing the weight of the polymer after heating and removing the volatile component by the weight of the polymer as it was before removing the volatile component) is 90% or more
  • a mixture of 50 parts of n-butyl acrylate and 10 parts of acrylic acid was added from a rubber septum and further heated at 110 ° C. for 7 hours. In this manner, a toluene solution of a block copolymer of styrene-butyl acrylate / acrylic acid was obtained. Subsequently, the obtained block copolymer solution was placed in an autoclave equipped with a stirrer.
  • a polymer-8 having a polymer unit content of about 40% based on colorless and transparent styrene was obtained.
  • the composition, ratio, weight average molecular weight, and glass transition temperature of the obtained polymer-8 are shown in Table 1.
  • the molecular weight distribution (Mw / Mn) of the polymer 8 was 1.2 to 1.3.
  • a positive electrode active material slurry, a positive electrode, and a battery were produced in the same manner as in Example 1 except that polymer-8 was used instead of polymer-1 as a binder constituting the positive electrode. Then, the output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics of the obtained batteries were evaluated. The results are shown in Table 2.
  • Example 2 (Comparative Example 2) In Example 1, a positive electrode active material slurry, an electrode, and a battery were prepared in the same manner as in Example 1 except that polyvinylidene fluoride was used instead of polymer-1 as a binder constituting the electrode. Then, the output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics of the obtained batteries were evaluated. The results are shown in Table 2.
  • a block polymer that does not contain a halogen atom and does not have an unsaturated bond in the main chain is used for an electrode for a secondary battery.
  • a battery having excellent characteristics, high temperature characteristics, and low temperature characteristics can be obtained.
  • the block polymer has n-butyl acrylate as the segment A having high compatibility with the electrolytic solution, styrene as the segment B having low compatibility, and the ratio of segment A to segment B
  • Example 1 using a block polymer in the range of 30:70 to 70:30 as a binder is excellent in all of output characteristics, cycle characteristics, high temperature characteristics, and low temperature characteristics, and particularly excellent in output characteristics and cycle characteristics. Shows the effect.

Abstract

La présente invention concerne une électrode pour un accumulateur qui est utilisée dans un accumulateur lithium ion ou similaire et présente en outre des caractéristiques améliorées à haute température et des caractéristiques de cycle à long terme. La présente invention concerne spécifiquement une électrode pour un accumulateur, qui est obtenue par laminage d'une couche de matériau actif d'électrode sur un collecteur, ladite couche de matériau actif d'électrode contenant un copolymère séquencé qui ne contient aucun atome d'halogène et comporte une chaîne principale ne contenant aucune liaison non saturée. La présente invention concerne également spécifiquement un accumulateur comprenant une électrode positive, une solution d'électrolyte, un séparateur et une électrode négative, ladite électrode positive et/ou l'électrode négative étant l'électrode décrite précédemment pour un accumulateur. Il est préférable que le polymère séquencé soit formé d'un segment qui est compatible avec la solution d'électrolyte et d'un segment qui n'est pas compatible avec la solution d'électrolyte.
PCT/JP2010/066817 2009-09-28 2010-09-28 Électrode pour accumulateur, liant pour électrode d'accumulateur et accumulateur WO2011037254A1 (fr)

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JP2013164972A (ja) * 2012-02-10 2013-08-22 Mitsubishi Rayon Co Ltd 二次電池電極バインダ用重合体とその製造方法、二次電池用電極、およびリチウムイオン二次電池
JP2014001368A (ja) * 2012-05-24 2014-01-09 Toyota Industries Corp ポリマー
WO2014024937A1 (fr) * 2012-08-09 2014-02-13 日本ゼオン株式会社 Électrode négative pour cellule secondaire, cellule secondaire, composition de bouillie, et procédé de fabrication
WO2014088070A1 (fr) * 2012-12-05 2014-06-12 日本ゼオン株式会社 Batterie secondaire au lithium-ion
WO2014148064A1 (fr) * 2013-03-22 2014-09-25 日本ゼオン株式会社 Composition de pâte pour électrode négative pour batterie secondaire au lithium-ion, électrode négative pour batterie secondaire au lithium-ion et batterie secondaire au lithium-ion
WO2014181523A1 (fr) * 2013-05-07 2014-11-13 株式会社豊田自動織機 Polymère et son procédé de fabrication
WO2019131597A1 (fr) * 2017-12-27 2019-07-04 株式会社ネオス Copolymère acrylique séquencé et film antibuée en contenant
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WO2024040489A1 (fr) * 2022-08-25 2024-02-29 宁德时代新能源科技股份有限公司 Polymère fonctionnel, suspension d'électrode, feuille d'électrode, batterie et appareil électrique

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10241693A (ja) * 1997-02-26 1998-09-11 Jsr Corp 水素吸蔵電極用バインダー
JP2006278303A (ja) * 2005-03-25 2006-10-12 Nippon Zeon Co Ltd 非水電解質二次電池電極用バインダー、バインダー組成物、電極用組成物、ならびに電極
JP2007048462A (ja) * 2005-07-13 2007-02-22 Nippon Soda Co Ltd 電極作製用結着剤、電極及びポリマー電池
JP2009151959A (ja) * 2007-12-19 2009-07-09 Hitachi Maxell Ltd 非水電解質二次電池用正極、非水電解質二次電池および電子機器
JP2010205449A (ja) * 2009-02-27 2010-09-16 Nippon Zeon Co Ltd 全固体二次電池用固体電解質層、全固体二次電池用積層体および全固体二次電池

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1086516C (zh) * 1997-09-19 2002-06-19 中国科学院化学研究所 一种锂电池正极材料及其制备方法和用途
US6225003B1 (en) 1998-10-26 2001-05-01 Mitsubishi Chemical Corporation Electrode materials having an elastomer binder and associated electrochemical and fabrication process
JP2002141068A (ja) 2000-10-31 2002-05-17 Nof Corp 非水系電池電極形成用バインダー、電極合剤、電極構造体及び非水系電池
KR20040008961A (ko) * 2002-07-20 2004-01-31 차민호 아바타를 이용한 차량상태 표시장치
CN101492596B (zh) * 2005-03-23 2011-11-23 日本瑞翁株式会社 非水电解质二次电池电极用粘合剂、电极以及非水电解质二次电池
TWI467840B (zh) * 2005-09-02 2015-01-01 A123 Systems Inc 奈米組成電極以及其相關裝置
TW200740913A (en) * 2006-02-02 2007-11-01 Jsr Corp Polymer composition, paste for secondary battery electrode, and secondary battery electrode

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10241693A (ja) * 1997-02-26 1998-09-11 Jsr Corp 水素吸蔵電極用バインダー
JP2006278303A (ja) * 2005-03-25 2006-10-12 Nippon Zeon Co Ltd 非水電解質二次電池電極用バインダー、バインダー組成物、電極用組成物、ならびに電極
JP2007048462A (ja) * 2005-07-13 2007-02-22 Nippon Soda Co Ltd 電極作製用結着剤、電極及びポリマー電池
JP2009151959A (ja) * 2007-12-19 2009-07-09 Hitachi Maxell Ltd 非水電解質二次電池用正極、非水電解質二次電池および電子機器
JP2010205449A (ja) * 2009-02-27 2010-09-16 Nippon Zeon Co Ltd 全固体二次電池用固体電解質層、全固体二次電池用積層体および全固体二次電池

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012256541A (ja) * 2011-06-09 2012-12-27 Nippon Zeon Co Ltd 二次電池用電極、二次電池電極用バインダー、製造方法及び二次電池
JP2013164972A (ja) * 2012-02-10 2013-08-22 Mitsubishi Rayon Co Ltd 二次電池電極バインダ用重合体とその製造方法、二次電池用電極、およびリチウムイオン二次電池
JP2014001368A (ja) * 2012-05-24 2014-01-09 Toyota Industries Corp ポリマー
JPWO2014024937A1 (ja) * 2012-08-09 2016-07-25 日本ゼオン株式会社 二次電池用負極、二次電池、スラリー組成物、及び製造方法
WO2014024937A1 (fr) * 2012-08-09 2014-02-13 日本ゼオン株式会社 Électrode négative pour cellule secondaire, cellule secondaire, composition de bouillie, et procédé de fabrication
JPWO2014088070A1 (ja) * 2012-12-05 2017-01-05 日本ゼオン株式会社 リチウムイオン二次電池
WO2014088070A1 (fr) * 2012-12-05 2014-06-12 日本ゼオン株式会社 Batterie secondaire au lithium-ion
WO2014148064A1 (fr) * 2013-03-22 2014-09-25 日本ゼオン株式会社 Composition de pâte pour électrode négative pour batterie secondaire au lithium-ion, électrode négative pour batterie secondaire au lithium-ion et batterie secondaire au lithium-ion
JPWO2014148064A1 (ja) * 2013-03-22 2017-02-16 日本ゼオン株式会社 リチウムイオン二次電池負極用スラリー組成物、リチウムイオン二次電池用負極およびリチウムイオン二次電池
US10566627B2 (en) 2013-03-22 2020-02-18 Zeon Corporation Slurry composition for negative electrode for lithium-ion secondary battery, negative electrode for lithium-ion secondary battery, and lithium-ion secondary battery
WO2014181523A1 (fr) * 2013-05-07 2014-11-13 株式会社豊田自動織機 Polymère et son procédé de fabrication
WO2019131597A1 (fr) * 2017-12-27 2019-07-04 株式会社ネオス Copolymère acrylique séquencé et film antibuée en contenant
JPWO2019131597A1 (ja) * 2017-12-27 2020-12-24 株式会社ネオス アクリル系ブロック共重合体及びそれを含む防曇膜
JP7239490B2 (ja) 2017-12-27 2023-03-14 株式会社ネオス アクリル系ブロック共重合体及びそれを含む防曇膜
CN112500542A (zh) * 2020-11-20 2021-03-16 珠海冠宇电池股份有限公司 一种用于负极片的水溶性聚合物、制备方法和负极片
CN112500543A (zh) * 2020-11-20 2021-03-16 珠海冠宇电池股份有限公司 一种用于正极片的脂溶性聚合物、制备方法和正极片

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CN102549820A (zh) 2012-07-04
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