WO2019073595A1 - Batterie secondaire au lithium-ion - Google Patents

Batterie secondaire au lithium-ion Download PDF

Info

Publication number
WO2019073595A1
WO2019073595A1 PCT/JP2017/037184 JP2017037184W WO2019073595A1 WO 2019073595 A1 WO2019073595 A1 WO 2019073595A1 JP 2017037184 W JP2017037184 W JP 2017037184W WO 2019073595 A1 WO2019073595 A1 WO 2019073595A1
Authority
WO
WIPO (PCT)
Prior art keywords
ion secondary
secondary battery
lithium ion
positive electrode
active material
Prior art date
Application number
PCT/JP2017/037184
Other languages
English (en)
Japanese (ja)
Inventor
良太 ▲柳▼澤
Original Assignee
Ｎｅｃエナジーデバイス株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ｎｅｃエナジーデバイス株式会社 filed Critical Ｎｅｃエナジーデバイス株式会社
Priority to CN201780095520.7A priority Critical patent/CN111164817B/zh
Priority to PCT/JP2017/037184 priority patent/WO2019073595A1/fr
Priority to JP2019547880A priority patent/JPWO2019073595A1/ja
Publication of WO2019073595A1 publication Critical patent/WO2019073595A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H01M50/494—Tensile strength
    • 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
    • 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
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • 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
    • H01M10/058—Construction or manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • 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
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to a lithium ion secondary battery.
  • Lithium ion secondary batteries are characterized by high energy density, and are widely used as power sources for mobile phones, notebook computers, electric cars and the like. In lithium ion secondary batteries, since a flammable organic solvent is used as a main solvent of the electrolyte, safety against ignition and explosion is required.
  • Patent Document 1 Japanese Patent Application Laid-Open No. 2013-251281.
  • Patent Document 1 Japanese Patent Laid-Open No. 2013-251281 discloses a positive electrode having a positive electrode active material layer containing a positive electrode active material on the surface of a positive electrode current collector, and a negative electrode active containing a negative electrode active material on the surface of the negative electrode current collector.
  • An electrode assembly comprising a negative electrode having a material layer, a separator disposed between the positive electrode and the negative electrode, and a battery case for containing the electrode assembly together with an electrolytic solution;
  • a lithium secondary battery is described in which the value of the ratio to the energy capacity at the time of charging is 4.5 cm 2 / Wh or more, and the electrical resistivity of the positive electrode is 10 ⁇ ⁇ cm to 450 ⁇ ⁇ cm. .
  • lithium ion secondary batteries With the increase in size and energy density of lithium ion secondary batteries, further improvement in safety of lithium ion secondary batteries is required.
  • a high capacity type positive electrode active material such as lithium nickel-containing composite oxide is used, or a positive electrode
  • the thickness of the current collector layer of the negative electrode is reduced or the density of the positive electrode active material layer is increased, the thermal stability of the lithium ion secondary battery may be reduced, and the safety of the battery may be deteriorated. It became clear.
  • the present invention has been made in view of the above circumstances, and provides a lithium ion secondary battery having excellent battery characteristics such as cycle characteristics and battery safety.
  • the present inventors diligently studied to achieve the above object. As a result, by setting the direct current resistance between the positive and negative electrodes in the lithium ion secondary battery after the nail penetration test under specific conditions to a specific range, a trade-off exists between battery characteristics such as cycle characteristics and battery safety. It has been revealed that a lithium ion secondary battery can be obtained which can improve the off relationship and has both battery characteristics such as cycle characteristics and battery safety characteristics. That is, the scale of direct current resistance between positive and negative electrodes in a lithium ion secondary battery after a nail penetration test performed under a specific condition is a lithium ion secondary battery excellent in the balance of battery characteristics such as cycle characteristics and battery safety. The inventors have found that the present invention is effective as a design guideline for realization.
  • the present invention was devised based on such knowledge. That is, according to the present invention, the following lithium ion secondary battery is provided.
  • a positive electrode having a positive electrode current collector layer and a positive electrode active material layer a negative electrode having a negative electrode current collector layer and a negative electrode active material layer, a non-aqueous electrolyte containing a lithium salt, and between the positive electrode and the negative electrode
  • a lithium ion secondary battery in which a sandwiched separator is contained in a container In a fully charged state under a 25 ° C. environment, a SUS304 nail with a diameter of 3 mm and a length of 70 mm is pierced at the center of the lithium ion secondary battery at a speed of 80 mm / sec to short the lithium ion secondary battery.
  • the lithium ion secondary battery When the nail penetration test was conducted, After the nail penetration test, the lithium ion secondary battery is short-circuit discharged, and when the voltage is in the range of 0.001 V to 0.100 V, the direct current resistance between the positive and negative electrodes in the lithium ion secondary battery is 0.
  • a lithium ion secondary battery having 1 ⁇ or more and 300 ⁇ or less.
  • the present invention it is possible to provide a lithium ion secondary battery which is excellent in battery characteristics such as cycle characteristics and battery safety.
  • the lithium ion secondary battery according to the present embodiment includes a positive electrode having a positive electrode current collector layer and a positive electrode active material layer, a negative electrode having a negative electrode current collector layer and a negative electrode active material layer, and a non-aqueous electrolysis containing a lithium salt.
  • a liquid and a separator sandwiched between the positive electrode and the negative electrode are accommodated in a container. Then, in a fully charged state under a 25 ° C.
  • a nail made of SUS304 with a diameter of 3 mm and a length of 70 mm is pierced at the center of the lithium ion secondary battery at a speed of 80 mm / sec to complete the lithium ion secondary battery
  • the lithium ion secondary battery is short-circuit discharged after the nail penetration test when the nail penetration test is performed to short-circuit the lithium ion secondary battery, and when the voltage is in the range of 0.001 V or more and 0.100 V or less
  • the direct current resistance between positive and negative electrodes in the battery is 0.1 ⁇ or more and 300 ⁇ or less.
  • a high capacity type positive electrode active material such as a lithium nickel-containing composite oxide is used, or It is apparent that if the thickness of the current collector layer is reduced or the density of the positive electrode active material layer is increased, the thermal stability of the lithium ion secondary battery may be reduced and the safety of the battery may be deteriorated. Became. Also, according to the study of the present inventor, it has become clear that if the electrical resistance of the electrode is increased to improve the safety of the battery, then the battery characteristics such as cycle characteristics may be deteriorated.
  • the present inventor has found that there is a trade-off relationship between battery characteristics such as cycle characteristics and battery safety in the conventional lithium ion secondary battery. Therefore, the present inventors diligently studied to achieve the above object. As a result, by setting the direct current resistance between positive and negative electrodes in the lithium ion secondary battery after the nail penetration test performed under the above conditions to the above range, a trade-off between battery characteristics such as cycle characteristics and battery safety It has been revealed that a lithium ion secondary battery can be obtained which can improve the relationship of (1) and have both battery characteristics such as cycle characteristics and battery safety characteristics.
  • the scale of direct current resistance between positive and negative electrodes in a lithium ion secondary battery after a nail penetration test performed under a specific condition is a lithium ion secondary battery excellent in the balance of battery characteristics such as cycle characteristics and battery safety. It was found for the first time that it was effective as a design guideline to realize it.
  • the lower limit of the direct current resistance between the positive and negative electrodes after the nail penetration test is 0.1 ⁇ or more, preferably 1 ⁇ or more, more preferably 2 ⁇ or more, further preferably 10 ⁇
  • the resistance is more preferably 40 ⁇ or more, still more preferably 60 ⁇ or more, and particularly preferably 80 ⁇ or more.
  • the safety of the lithium ion secondary battery can be effectively improved by setting the direct current resistance between the positive and negative electrodes after the nail penetration test to the above lower limit value or more. it can.
  • the upper limit of the direct current resistance between the positive and negative electrodes after the nail penetration test is 300 ⁇ or less, preferably 250 ⁇ or less, more preferably 200 ⁇ or less, still more preferably 150 ⁇ . The following is particularly preferable: 130 ⁇ or less.
  • the fully charged state is a voltage of 4.2 V at a constant current of 1 C with respect to a lithium ion secondary battery at 25 ° C. using a constant current constant voltage (CC-CV) method. Constant current charging up to a constant voltage, and then a constant voltage charging to a charge termination current of 0.015 C at a constant voltage of 4.2 V.
  • the direct current resistance between the positive and negative electrodes after the above-mentioned nailing test of the lithium ion secondary battery according to the present embodiment is: (A) the compounding ratio of the positive electrode active material layer and the negative electrode active material layer; ) It is possible to realize by appropriately selecting the type of the current collector layer and the like. Among these, for example, the amount of the conductive additive in the positive electrode active material layer is in a specific range, the separator having high heat resistance and high elongation is used, the positive electrode current collector layer, the negative electrode current collector The use of a separator having a tensile elongation greater than that of the layer, etc. is mentioned as a factor for setting the direct current resistance between the positive and negative electrodes in the lithium ion secondary battery after the above-mentioned nail penetration test to a desired numerical range.
  • the lithium ion secondary battery according to the present embodiment is excellent in battery safety is not necessarily clear, such a lithium ion secondary battery has high battery resistance even if foreign matter enters the battery and shorts, for example. Since the range can be maintained, it is possible to suppress the flow of a large current, and as a result, it is possible to suppress the thermal runaway of the battery.
  • the lithium ion secondary battery according to this embodiment preferably has a cell rated capacity of 5 Ah or more, more preferably 7 Ah or more. Moreover, in the lithium ion secondary battery according to the present embodiment, the number of laminations or the number of laminations of the positive electrode in the central portion is preferably 10 or more, more preferably 15 or more, and still more preferably 20 or more . Thus, the capacity of the lithium ion secondary battery according to the present embodiment can be increased. Further, even with such a high capacity, the lithium ion secondary battery according to the present embodiment is excellent in the short circuit resistance, and it is possible to suppress the thermal runaway of the battery.
  • the form and type of the lithium ion secondary battery of the present embodiment are not particularly limited, but, for example, the following configuration can be made.
  • FIG. 1 schematically shows the structure of a laminated battery.
  • Stacked battery 100 includes battery elements in which positive electrode 1 and negative electrode 6 are alternately laminated in multiple layers with separator 20 interposed therebetween, and these battery elements are a flexible film together with an electrolytic solution (not shown). It is housed in a 30 container.
  • the positive electrode terminal 11 and the negative electrode terminal 16 are electrically connected to the battery element, and a part or all of the positive electrode terminal 11 and the negative electrode terminal 16 are drawn out of the flexible film 30. .
  • the positive electrode 1 is provided with the coated part (positive electrode active material layer 2) and the uncoated part of the positive electrode active material on the front and back of the positive electrode collector layer 3, and the negative electrode 6 is on the front and back of the negative electrode collector layer 8.
  • the coated part of the negative electrode active material (negative electrode active material layer 7) and the uncoated part are provided.
  • the uncoated portion of the positive electrode active material in the positive electrode current collector layer 3 is used as a positive electrode tab 10 for connecting to the positive electrode terminal 11, and the uncoated portion of the negative electrode active material in the negative electrode current collector layer 8 is connected to the negative electrode terminal 16.
  • the negative electrode tab 5 of FIG. The positive electrode tabs 10 are assembled on the positive electrode terminal 11 and connected together by ultrasonic welding etc. together with the positive electrode terminal 11, and the negative electrode tabs 5 are assembled on the negative electrode terminal 16 connected together by ultrasonic welding etc. together with the negative electrode terminal 16. Be done.
  • one end of the positive electrode terminal 11 is drawn out of the flexible film 30, and one end of the negative electrode terminal 16 is also drawn out of the flexible film 30.
  • an insulating member can be formed at the boundary 4 between the coated part (positive electrode active material layer 2) and the non-coated part of the positive electrode active material, and the insulating member is not only the boundary 4 but also the positive electrode tab. 10 and near the boundary between the positive electrode active material.
  • an insulating member can be formed on the boundary portion 9 between the coated portion (negative electrode active material layer 7) and the non-coated portion of the negative electrode active material as required, and the boundary between both the negative electrode tab 5 and the negative electrode active material It can be formed near the part.
  • the outer dimension of the negative electrode active material layer 7 is larger than the outer dimension of the positive electrode active material layer 2 and smaller than the outer dimension of the separator 20.
  • FIG. 2 schematically shows the configuration of a wound battery, and the container etc. are not shown.
  • the wound battery 101 includes a battery element in which a positive electrode 1 and a negative electrode 6 are stacked via a separator 20 and wound, and this battery element is made of a flexible film together with an electrolytic solution (not shown). Contained in the The positive electrode terminal and the negative electrode terminal are also electrically connected to the battery element of the wound battery 101, and the other configuration is substantially the same as that of the laminated battery 100, and thus further description is omitted here.
  • the positive electrode 1 used in the present embodiment can be appropriately selected from among positive electrodes that can be used for known lithium ion secondary batteries, according to the application and the like.
  • the active material used for the positive electrode 1 is preferably a material having high electron conductivity so that lithium ions can be reversibly released and stored, and electron transport can be easily performed.
  • the positive electrode active material used for the positive electrode 1 is not particularly limited.
  • lithium composite oxide having a layered rock salt structure or spinel structure, lithium iron phosphate having an olivine structure, etc. are used. be able to.
  • lithium complex oxide lithium manganate (LiMn 2 O 4 ); lithium cobaltate (LiCoO 2 ); lithium nickelate (LiNiO 2 ); at least a part of manganese, cobalt and nickel of these lithium compounds Those substituted with other metal elements such as aluminum, magnesium, titanium, zinc, etc .; Nickel-substituted lithium manganate in which at least part of manganese in lithium manganate is substituted with nickel; at least part of nickel in lithium nickel nickelate Substituted cobalt-substituted lithium nickelate; part of manganese of lithium-substituted lithium manganate substituted with another metal (eg, at least one of aluminum, magnesium, titanium, zinc); nickel of cobalt-substituted lithium nickelate; Other metal
  • lithium-containing composite oxides having a layered crystal structure examples include lithium-nickel-containing composite oxides.
  • this lithium nickel-containing composite oxide one in which a part of nickel at the nickel site is replaced with another metal can be used.
  • metals other than Ni that occupy the nickel site include at least one metal selected from Mn, Co, Al, Mg, Fe, Cr, Ti, and In.
  • the lithium nickel-containing composite oxide preferably contains Co as a metal other than Ni occupying nickel sites.
  • the lithium-nickel-containing composite oxide more preferably contains Mn or Al in addition to Co, that is, lithium-nickel-cobalt-manganese composite oxide (NCM) having a layered crystal structure, lithium-nickel having a layered crystal structure Cobalt aluminum complex oxide (NCA) or a mixture thereof can be suitably used.
  • NCM lithium-nickel-cobalt-manganese composite oxide
  • NCA Cobalt aluminum complex oxide
  • lithium nickel-containing composite oxide having a layered crystal structure for example, one represented by the following formula (1) can be used.
  • Me1 is Mn or Al
  • Me2 is at least one selected from the group consisting of Mn, Al, Mg, Fe, Cr, Ti, In (except metals of the same type as Me1), ⁇ 0.5 ⁇ a ⁇ 0.1, 0.1 ⁇ b ⁇ 1, 0 ⁇ c ⁇ 0.5, 0 ⁇ d ⁇ 0.5)
  • the average particle diameter of the positive electrode active material is, for example, preferably 0.1 to 50 ⁇ m, more preferably 1 to 30 ⁇ m, and still more preferably 2 to 25 ⁇ m, from the viewpoint of reactivity with the electrolytic solution, rate characteristics, and the like.
  • the average particle diameter means a particle diameter (median diameter: D 50 ) at an integrated value of 50% in a particle size distribution (volume basis) by a laser diffraction scattering method.
  • the positive electrode 1 includes a positive electrode current collector layer 3 and a positive electrode active material layer 2 on the positive electrode current collector layer 3.
  • the positive electrode 1 is disposed such that the positive electrode active material layer 2 faces the negative electrode active material layer 7 on the negative electrode current collector layer 8 with the separator interposed therebetween.
  • the positive electrode 1 in the present embodiment can be manufactured by a known method. For example, after a positive electrode active material, a binder resin, and a conductive additive are dispersed in an organic solvent to obtain a positive electrode slurry, this positive electrode slurry is applied to the positive electrode current collector layer 3 and dried, and pressed as necessary. Thus, the method of forming the positive electrode active material layer 2 on the positive electrode current collector layer 3 can be adopted.
  • NMP N-methyl-2-pyrrolidone
  • NMP N-methyl-2-pyrrolidone
  • binder resin what is generally used as binder resin for positive electrodes, such as a polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF), can be used, for example.
  • PTFE polytetrafluoroethylene
  • PVDF polyvinylidene fluoride
  • the content of the binder resin in the positive electrode active material layer 2 is preferably 0.1 parts by mass or more and 10.0 parts by mass or less, based on 100 parts by mass of the entire positive electrode active material layer 2. It is more preferable that it is mass part or more and 5.0 mass parts or less, and it is further more preferable that it is 1.0 mass part or more and 5.0 mass parts or less.
  • the balance of the coating property of a positive electrode slurry, the binding property of a binder, and the battery characteristic as the content of binder resin is in the said range is much more excellent.
  • the ratio of a positive electrode active material becomes large as content of binder resin is below the said upper limit, and since the capacity
  • the positive electrode active material layer 2 can contain a conductive support agent in addition to the positive electrode active material and the binder resin.
  • the conductive aid is not particularly limited as long as it improves the conductivity of the positive electrode, and examples thereof include carbon black, ketjen black, acetylene black, natural graphite, artificial graphite, carbon fiber and the like. These conductive aids may be used alone or in combination of two or more.
  • the content of the conductive additive in the positive electrode active material layer 2 is preferably more than 1.0 parts by mass and less than 4.0 parts by mass, based on 100 parts by mass of the whole of the positive electrode active material layer 2. It is more preferably 2 parts by mass or more and 3.5 parts by mass or less, still more preferably 1.5 parts by mass or more and 3.5 parts by mass or less and 2.0 parts by mass or more and 3.5 parts by mass or less Is particularly preferred.
  • the balance of the coating property of a positive electrode slurry, the binding property of binder resin, and battery characteristics as the content of the conductive support agent is within the above range is further excellent.
  • the ratio of a positive electrode active material becomes large as content of a conductive support agent is less than or less than the said upper limit, and the capacity
  • the positive electrode current collector layer 3 aluminum, stainless steel, nickel, titanium, an alloy of these, or the like can be used. As the shape, foil, flat form, mesh form etc. are mentioned, for example. In particular, an aluminum foil can be suitably used.
  • the thickness of the positive electrode collector layer 3 is not particularly limited, it is, for example, 1 ⁇ m or more and 30 ⁇ m or less.
  • the thickness of the positive electrode current collector layer 3 is smaller, the positive electrode current collector layer 3 is more easily deformed or broken, so that the safety of the lithium ion secondary battery is easily deteriorated.
  • the thickness of the positive electrode current collector layer 3 is thin, the deterioration of the safety of the battery can be suppressed.
  • the positive electrode current collection is preferably less than 25 ⁇ m, more preferably less than 20 ⁇ m, and particularly preferably less than 18 ⁇ m.
  • the tensile elongation of the positive electrode collector layer 3 measured according to 6.3 of JISL1913: 2010 is less than 10%, and it is more preferable that it is less than 8%.
  • the separator 20 is torn by a sharp metal such as lithium dendrite, for example, the expansion of the positive electrode current collector layer 3 can be suppressed, so the contact between the metal that has broken the separator 20 and the positive and negative electrodes is suppressed. be able to. As a result, thermal runaway or the like of the lithium ion secondary battery can be suppressed, and safety can be further improved.
  • the density of the positive electrode active material layer 2 is not particularly limited, for example, it is preferably not more than 2.0 g / cm 3 or more 4.0g / cm 3, 2.4g / cm 3 or more 3.8 g / cm 3 or less Some are more preferable, and 2.8 g / cm 3 or more and 3.6 g / cm 3 or less are more preferable.
  • the density of the positive electrode active material layer 2 is higher, battery characteristics such as cycle characteristics of the lithium ion secondary battery are likely to be deteriorated.
  • the lithium ion secondary battery according to the present embodiment can suppress the deterioration of the battery characteristics such as the cycle characteristics.
  • the density of the positive electrode active material layer 2 is 3.0 g / cm 3 or more from the viewpoint of further improving the energy density of the obtained lithium ion secondary battery while making battery characteristics such as cycle characteristics better.
  • it is 3.2 g / cm 3 or more, more preferably 3.3 g / cm 3 or more.
  • the density of the positive electrode active material layer 2 is 4.0 g / cm 3 or less, more preferably 3.8 g / cm 3 or less More preferably, it is 3.6 g / cm 3 or less.
  • the thickness (the sum of the thicknesses on both sides) of the positive electrode active material layer 2 is not particularly limited, and can be appropriately set according to the desired characteristics. For example, it can be set thick in terms of energy density, and can be set thin in terms of output characteristics.
  • the thickness (total of the thickness on both sides) of the positive electrode active material layer 2 can be appropriately set, for example, in the range of 20 ⁇ m to 500 ⁇ m, preferably 40 ⁇ m to 400 ⁇ m, and more preferably 60 ⁇ m to 300 ⁇ m.
  • the thickness (thickness of one side) of the positive electrode active material layer 2 is not particularly limited, and can be appropriately set according to the desired characteristics.
  • the positive electrode active material layer 2 can be appropriately set, for example, in the range of 10 ⁇ m to 250 ⁇ m, preferably 20 ⁇ m to 200 ⁇ m, and more preferably 30 ⁇ m to 150 ⁇ m.
  • the negative electrode 6 which concerns on this embodiment can be suitably selected from the negative electrodes which can be used for a well-known lithium ion secondary battery according to a use etc.
  • the negative electrode active material used for the negative electrode 6 can be appropriately set according to the application etc. as long as it can be used for the negative electrode.
  • the negative electrode 6 has a structure including a negative electrode current collector layer 8 and a negative electrode active material layer 7 formed on the negative electrode current collector layer 8.
  • the negative electrode active material layer 7 preferably contains a negative electrode active material and a binder resin, and preferably further contains a conductive auxiliary agent in order to enhance the conductivity.
  • the negative electrode active material is not particularly limited as long as it is an active material for a negative electrode capable of inserting and extracting lithium ions, but a carbonaceous material can be used.
  • the carbonaceous material include graphite, amorphous carbon (for example, graphitizable carbon, non-graphitizable carbon), diamond-like carbon, fullerene, carbon nanotube, carbon nanohorn and the like.
  • graphite natural graphite and artificial graphite can be used, and inexpensive natural graphite is preferable from the viewpoint of material cost.
  • Examples of amorphous carbon include those obtained by heat-treating coal pitch coke, petroleum pitch coke, acetylene pitch coke and the like.
  • lithium metal materials, alloy materials such as silicon and tin, oxide materials such as Nb 2 O 5 and TiO 2 , or a composite thereof can be used.
  • the negative electrode active material may be used alone or in combination of two or more.
  • the average particle diameter of the negative electrode active material is preferably 2 ⁇ m or more, more preferably 5 ⁇ m or more, from the viewpoint of suppressing side reactions during charge and discharge to suppress a decrease in charge and discharge efficiency From (Smoothness of the negative electrode surface, etc.), 40 ⁇ m or less is preferable and 30 ⁇ m or less is more preferable.
  • the average particle diameter means a particle diameter (median diameter: D 50 ) at an integrated value of 50% in a particle size distribution (volume basis) by a laser diffraction scattering method.
  • the negative electrode 6 in the present embodiment can be manufactured by a known method.
  • this slurry is applied to the negative electrode current collector layer 8 and dried, and pressed as necessary to form the negative electrode active material layer 7 A method etc. can be adopted.
  • the method of applying the negative electrode slurry include a doctor blade method, a die coater method, and a dip coating method. If necessary, additives such as an antifoaming agent and a surfactant may be added to the slurry.
  • the content of the binder resin in the negative electrode active material layer 7 is preferably 0.1 parts by mass or more and 10.0 parts by mass or less, based on 100 parts by mass of the entire negative electrode active material layer 7. It is more preferable that it is mass part or more and 8.0 mass parts or less, it is more preferable that it is 1.0 mass part or more and 5.0 mass parts or less, and it is 1.0 mass part or more and 3.0 mass parts or less Is particularly preferred.
  • the content of the binder resin is in the above range, the balance between the coatability of the negative electrode slurry, the binding property of the binder resin, and the battery characteristics is more excellent.
  • the ratio of a negative electrode active material becomes large as content of binder resin is below the said upper limit, and the capacity
  • an organic solvent such as N-methyl-2-pyrrolidone (NMP) or water
  • NMP N-methyl-2-pyrrolidone
  • a binder resin for an organic solvent such as polyvinylidene fluoride (PVDF)
  • PVDF polyvinylidene fluoride
  • rubber binders for example, SBR (styrene-butadiene rubber)
  • acrylic binder resins can be used.
  • aqueous binder resin can be used in the form of an emulsion.
  • water it is preferable to use an aqueous binder and a thickener such as CMC (carboxymethyl cellulose) in combination.
  • the negative electrode active material layer 7 may contain a conductive auxiliary, as necessary.
  • a conductive aid conductive materials generally used as a conductive aid for a negative electrode, such as carbonaceous materials such as carbon black, ketjen black and acetylene black can be used.
  • the content of the conductive additive in the negative electrode active material layer 7 is preferably 0.1 parts by mass or more and 3.0 parts by mass or less, based on 100 parts by mass of the whole of the negative electrode active material layer 7. The content is more preferably 1 part by mass or more and 2.0 parts by mass or less, and particularly preferably 0.2 parts by mass or more and 1.0 parts by mass or less.
  • the balance of the coating property of negative electrode slurry, the binding property of binder resin, and the battery characteristic as the content of a conductive support agent is in the above-mentioned range is much more excellent. Moreover, since the ratio of a negative electrode active material becomes large as content of a conductive support agent is below the said upper limit, and the capacity
  • the average particle size (primary particle size) of the conductive additive used for the positive electrode active material layer 2 and the negative electrode active material layer 7 is preferably in the range of 10 to 100 nm.
  • the average particle size (primary particle size) of the conductive aid is preferably 10 nm or more, more preferably 30 nm or more, and a sufficient number of contact points from the viewpoint of suppressing excessive aggregation of the conductive aid and uniformly dispersing in the negative electrode. From the viewpoint of forming a good conductive path, and is preferably 100 nm or less, more preferably 80 nm or less.
  • the conductive aid is in the form of fibers, those having an average diameter of 2 to 200 nm and an average fiber length of 0.1 to 20 ⁇ m can be mentioned.
  • the average particle diameter of the conductive additive is the median diameter (D 50 ), which means the particle diameter at an integrated value of 50% in the particle size distribution (volume basis) by the laser diffraction scattering method.
  • the thickness (total of the thickness on both sides) of the negative electrode active material layer 7 is not particularly limited, and can be appropriately set according to the desired characteristics. For example, it can be set thick in terms of energy density, and can be set thin in terms of output characteristics.
  • the thickness (total of the thickness on both sides) of the negative electrode active material layer 7 can be appropriately set, for example, in the range of 40 ⁇ m to 1000 ⁇ m, preferably 80 ⁇ m to 800 ⁇ m, and more preferably 120 ⁇ m to 600 ⁇ m.
  • the thickness (thickness of one side) of the negative electrode active material layer 7 is not particularly limited, and can be appropriately set according to desired characteristics. For example, it can be set thick in terms of energy density, and can be set thin in terms of output characteristics.
  • the thickness (thickness of one side) of the negative electrode active material layer 7 can be appropriately set, for example, in the range of 20 ⁇ m to 500 ⁇ m, preferably 40 ⁇ m to 400 ⁇ m, and more preferably 60 ⁇ m to 300 ⁇ m.
  • the density of the negative electrode active material layer 7 is not particularly limited, it is preferably, for example, 1.2 g / cm 3 or more and 2.0 g / cm 3 or less, and 1.3 g / cm 3 or more and 1.9 g / cm 3 or less Some are more preferable, and 1.4 g / cm 3 or more and 1.8 g / cm 3 or less are more preferable.
  • the negative electrode current collector layer 8 copper, stainless steel, nickel, titanium or an alloy thereof can be used. As the shape, foil, flat form, mesh form is mentioned.
  • the thickness of the negative electrode current collector layer 8 is not particularly limited, and is, for example, 1 ⁇ m or more and 20 ⁇ m or less.
  • the thickness of the negative electrode current collector layer 8 is thinner, the negative electrode current collector layer 8 is more easily deformed or broken, so that the safety of the lithium ion secondary battery is easily deteriorated.
  • the thickness of the negative electrode current collector layer 8 is thin, the deterioration of the safety of the battery can be suppressed.
  • the negative electrode current collection is preferably less than 15 ⁇ m, more preferably less than 12 ⁇ m, and particularly preferably less than 10 ⁇ m.
  • the tensile elongation of the negative electrode current collector layer 8 is preferably less than 10%, more preferably less than 5%, which is measured according to 6.3 of JIS L1913: 2010.
  • the expansion of the negative electrode current collector layer 8 can be suppressed, so the contact between the metal that has broken the separator 20 and the positive and negative electrodes is suppressed. be able to.
  • thermal runaway or the like of the lithium ion secondary battery can be suppressed, and safety can be further improved.
  • Non-aqueous electrolyte containing lithium salt The non-aqueous electrolytic solution containing a lithium salt used in the present embodiment can be appropriately selected from known ones depending on the type of electrode active material, the use of the lithium ion secondary battery, and the like.
  • lithium salt for example, LiClO 4, LiBF 6, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiB 10 Cl 10, LiAlCl 4, LiCl, LiBr, LiB Examples include (C 2 H 5 ) 4 , CF 3 SO 3 Li, CH 3 SO 3 Li, LiC 4 F 9 SO 3 , Li (CF 3 SO 2 ) 2 N, and lower fatty acid carboxylate lithium.
  • the solvent for dissolving the lithium salt is not particularly limited as long as it is generally used as a liquid for dissolving the electrolyte, and ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), carbonates such as vinylene carbonate (VC); lactones such as ⁇ -butyrolactone and ⁇ -valerolactone; trimethoxymethane Ethers such as 1,2-dimethoxyethane, diethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, etc.
  • EC ethylene carbonate
  • PC propylene carbonate
  • BC butylene carbonate
  • DMC dimethyl carbonate
  • EMC ethyl methyl carbonate
  • EMC ethyl methyl carbonate
  • DEC diethyl carbon
  • Sulfoxides such as dimethylsulfoxide, etc. 1,3-Dioxolane, 4-methyl-1,3-dioxola
  • Nitrogenous solvents such as acetonitrile, nitromethane, formamide and dimethylformamide; methyl formate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate, ethyl propionate and the like; organic acid esters such as phosphoric acid triester And diglymes; triglymes; sulfolanes such as sulfolane and methyl sulfolane; oxazolidinones such as 3-methyl-2-oxazolidinone; and sultones such as 1,3-propane sultone, 1,4-butane sultone and naphtha sultone. . These may be used singly or in combination of two or more.
  • a well-known member can be used for a container in this embodiment, and it is preferable to use the flexible film 30 from a viewpoint of weight reduction of a battery.
  • the flexible film 30 can use what provided the resin layer in front and back of the metal layer used as a base material.
  • the metal layer can be selected to have a barrier property to prevent leakage of the electrolytic solution and entry of moisture from the outside, and aluminum, stainless steel, etc. can be used.
  • a heat-sealable resin layer such as modified polyolefin is provided on at least one surface of the metal layer, and the heat-sealable resin layers of the flexible film 30 are opposed to each other through the battery element to make the battery element
  • the sheath is formed by heat-sealing the periphery of the part to be stored.
  • a resin layer such as a nylon film or a polyester film can be provided on the surface of the exterior body opposite to the surface on which the heat-fusible resin layer is formed.
  • the positive electrode terminal 11 may be made of aluminum or an aluminum alloy
  • the negative electrode terminal 16 may be copper or a copper alloy, or those plated with nickel.
  • Each terminal is drawn to the outside of the container, but a heat fusible resin can be provided in advance in a portion located at a portion of the respective terminal where the periphery of the package is heat welded.
  • Insulating member In the case of forming the insulating member at the boundary portions 4 and 9 between the coated portion and the non-coated portion of the active material, polyimide, glass fiber, polyester, polypropylene or those containing these in the structure can be used. Heat can be applied to these members to weld them to the boundaries 4 and 9, or a gel-like resin can be applied to the boundaries 4 and 9 and dried to form an insulating member.
  • the separator 20 according to the present embodiment preferably includes a resin layer containing a heat resistant resin as a main component.
  • the resin layer is formed of a heat resistant resin which is a main component.
  • the term "main component" means that the proportion in the resin layer is 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass or more, and 100% by mass. It means that you may.
  • the resin layer constituting the separator 20 according to the present embodiment may be a single layer or two or more layers.
  • Examples of the heat resistant resin forming the above resin layer include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, poly-m-phenylene terephthalate, poly-p-phenylene isophthalate, polycarbonate, polyester carbonate, aliphatic polyamide, all Aromatic polyamide, semiaromatic polyamide, wholly aromatic polyester, polyphenylene sulfide, polyparaphenylene benzobisoxazole, polyimide, polyarylate, polyetherimide, polyamideimide, polyacetal, polyetheretherketone, polysulfone, polyethersulfone, One or more selected from fluorine resins, polyether nitriles, modified polyphenylene ethers and the like can be mentioned.
  • polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, aliphatic polyamide, wholly aromatic polyamide, semiaromatic polyamide and all aromatic from the viewpoint of excellent balance of heat resistance, mechanical strength, stretchability, price and the like.
  • Family of polyesters one or more selected from polyethylene terephthalates, polybutylene terephthalates, aliphatic polyamides, wholly aromatic polyamides and semiaromatic polyamides are more preferred, and polyethylene terephthalates are preferred.
  • One or more selected from wholly aromatic polyamides are more preferable, and polyethylene terephthalate is more preferable.
  • the melting point of the separator 20 according to the present embodiment is preferably 220 ° C. or higher, more preferably 230 ° C. or higher, and 240 ° C. or higher from the viewpoint of improving the safety of the lithium ion secondary battery. Is more preferred.
  • the separator 20 according to the present embodiment preferably does not have a melting point, preferably has a decomposition temperature of 220 ° C. or higher, and 230 ° C. It is more preferable that it is the above, It is more preferable that it is 240 degreeC or more, It is especially preferable that it is 250 degreeC or more.
  • the battery By setting the melting point or decomposition temperature of the separator 20 according to the present embodiment to the above lower limit value or more, the battery generates heat and heat contraction of the separator 20 can be suppressed even when the temperature is high.
  • the contact area with the negative electrode can be suppressed.
  • thermal runaway or the like of the lithium ion secondary battery can be suppressed, and safety can be further improved.
  • the upper limit of the melting point of the separator 20 according to the present embodiment is not particularly limited, but is, for example, 500 ° C. or less, and preferably 400 ° C. or less from the viewpoint of stretchability.
  • the upper limit of the decomposition temperature of the separator according to the present embodiment is not particularly limited, but is, for example, 500 ° C. or less, and preferably 400 ° C. or less from the viewpoint of stretchability.
  • the average value of the tensile elongation in the MD direction and the tensile elongation in the TD direction of the separator according to this embodiment, which is measured according to 6.3 of JIS L 1913: 2010, is the positive electrode current collector layer 3 and the negative electrode current collector. It is preferable that the tensile elongation of the body layer 8 be larger than that of the body layer 8. Thus, even if the separator 20 is torn by a sharp metal such as lithium dendrite, for example, the positive and negative electrodes are easily covered by the separator 20 because the separator 20 extends more than the positive and negative electrode current collectors.
  • the contact between the metal that has broken through the separator 20 and the positive and negative electrodes can be suppressed by the extended separator 20.
  • thermal runaway or the like of the lithium ion secondary battery can be suppressed, and safety can be further improved.
  • the positive and negative electrodes are effectively covered, it is possible to suppress the contact between the metal that has broken through the separator 20 and the positive and negative electrodes. As a result, thermal runaway or the like of the lithium ion secondary battery can be suppressed, and safety can be further improved.
  • the upper limit value of the tensile elongation in the MD direction of the separator 20 and the tensile elongation in the TD direction measured according to 6.3 of JIS L 1913: 2010 is not particularly limited, the heat resistance viewpoint of the separator 20 Therefore, 100% or less is preferable, 70% or less is more preferable, and 50% or less is more preferable.
  • the tensile elongation in the MD direction of the separator 20 which is measured according to 6.3 of JIS L1913: 2010, is preferably 10% or more, and more preferably 12% or more.
  • the upper limit value of the tensile elongation in the MD direction of the separator 20 measured according to 6.3 of JIS L 1913: 2010 is not particularly limited, but 100% or less is preferable, 70% or less is more preferable, and 50% or less More preferable.
  • the resin layer which comprises the separator 20 which concerns on this embodiment is a porous resin layer.
  • the resin layer which comprises the separator 20 which concerns on this embodiment is a porous resin layer.
  • the porosity of the porous resin layer is preferably 20% to 80%, more preferably 30% to 70%, and still more preferably 40% to 60%. Is particularly preferred.
  • ⁇ porosity (%)
  • Ws basis weight (g / m 2 )
  • ds true density (g / cm 3 )
  • t film thickness ( ⁇ m).
  • the planar shape of the separator 20 according to the present embodiment is not particularly limited, and can be appropriately selected according to the shapes of the electrode and the current collector, and can be, for example, rectangular.
  • the thickness of the separator 20 according to the present embodiment is preferably 5 ⁇ m or more and 50 ⁇ m or less, more preferably 10 ⁇ m or more and 40 ⁇ m or less, and further preferably 10 ⁇ m or more and 30 ⁇ m from the viewpoint of balance of mechanical strength and lithium ion conductivity. It is below.
  • the separator 20 according to the present embodiment preferably further includes a ceramic layer on at least one surface of the resin layer from the viewpoint of further improving heat resistance.
  • the ceramic layer is preferably provided only on one side of the resin layer from the viewpoint of the handleability, productivity, etc. of the separator 20 according to the present embodiment, but the heat resistance of the separator 20 is further enhanced. From the viewpoint of further improving, it may be provided on both sides of the resin layer.
  • the separator 20 according to the present embodiment can further reduce the thermal contraction of the separator 20 by further including the ceramic layer, and can further prevent a short circuit between the electrodes.
  • the said ceramic layer can be formed by, for example, apply
  • the ceramic layer forming material for example, a material obtained by dissolving or dispersing an inorganic filler and a binder resin in a suitable solvent can be used.
  • the inorganic filler used for this ceramic layer can be suitably selected from the well-known materials used for the separator of a lithium ion secondary battery.
  • oxides, nitrides, sulfides, carbides and the like having high insulating properties are preferable, and are selected from aluminum oxide, boehmite, titanium oxide, silicon oxide, magnesium oxide, barium oxide, zirconium oxide, zinc oxide and iron oxide etc. It is more preferable to adjust one or two or more kinds of ceramics into particles. Among these, aluminum oxide, boehmite and titanium oxide are preferable.
  • the binder resin is not particularly limited, and examples thereof include cellulose resins such as carboxymethyl cellulose (CMC); acrylic resins; fluorine resins such as polyvinylidene fluoride (PVDF); and the like.
  • a binder resin may be used individually by 1 type, and may be used in combination of 2 or more types.
  • the solvent for dissolving or dispersing these components is not particularly limited, and is appropriately selected from, for example, water, alcohols such as ethanol, N-methylpyrrolidone (NMP), toluene, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), etc. Can be used.
  • alcohols such as ethanol, N-methylpyrrolidone (NMP), toluene, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), etc.
  • NMP N-methylpyrrolidone
  • DMC dimethyl carbonate
  • EMC ethyl methyl carbonate
  • the thickness of the ceramic layer is preferably 0.1 ⁇ m or more and 50 ⁇ m or less, more preferably 0.5 ⁇ m or more and 30 ⁇ m or less, from the viewpoint of the balance between heat resistance, mechanical strength, handleability and lithium ion conductivity. Preferably they are 1 micrometer or more and 15 micrometers or less.
  • Example 1 ⁇ Fabrication of positive electrode> 94.0 parts by mass of lithium nickel-containing composite oxide (chemical formula: LiNi 0.8 Co 0.15 Al 0.05 O 2 , average particle diameter: 6 ⁇ m) as a positive electrode active material, and carbon black as a conductive additive 3. 0 parts by mass, and 3.0 parts by mass of polyvinylidene fluoride (PVDF) as a binder resin were used. These were dispersed in an organic solvent to prepare a positive electrode slurry.
  • lithium nickel-containing composite oxide chemical formula: LiNi 0.8 Co 0.15 Al 0.05 O 2 , average particle diameter: 6 ⁇ m
  • PVDF polyvinylidene fluoride
  • This positive electrode slurry is continuously applied and dried on a 15 ⁇ m thick aluminum foil (tensile elongation: 6%) which is a positive electrode current collector, and then pressed to obtain a coated portion of the positive electrode current collector (positive electrode Active material layer: A positive electrode roll comprising a thickness of 60 ⁇ m on one side, a density of 3.35 g / cm 3 ) and an uncoated portion not coated was prepared. The positive electrode roll was punched out to leave a non-coated portion to be a tab for connecting to the positive electrode terminal, and was used as a positive electrode.
  • ⁇ Fabrication of negative electrode 96.7 parts by mass of natural graphite (average particle diameter: 16 ⁇ m) as a negative electrode active material, 0.3 parts by mass of carbon black as a conductive additive, 2.0 parts by mass of styrene butadiene rubber as a binder resin, thickener 1.0 mass part of carboxymethylcellulose was used as this. These were dispersed in water to prepare a negative electrode slurry.
  • the negative electrode slurry is continuously coated and dried on a copper foil (tensile elongation: 4%) having a thickness of 8 ⁇ m, which is a negative electrode current collector, and then pressed to form a coated portion of the negative electrode current collector (negative electrode Active material layer: A negative electrode roll provided with a thickness of 90 ⁇ m on one side, a density of 1.55 g / cm 3 ) and an uncoated portion not coated. The negative electrode roll was punched out to leave a non-coated portion to be a tab for connecting to the negative electrode terminal.
  • ⁇ Fabrication of Laminated Laminated Battery> The positive electrode and the negative electrode were stacked in a serpentine structure via a separator, and a negative electrode terminal and a positive electrode terminal were provided thereon to obtain a laminate.
  • a laminate type laminate battery is obtained by housing an electrolyte solution in which 1 M LiPF 6 is dissolved in a solvent composed of ethylene carbonate, diethyl carbonate and ethyl methyl carbonate, and the obtained laminate in a flexible film. Obtained.
  • the rated capacity of this laminate type laminate battery was 9.2 Ah, the positive electrode was 28 layers, and the negative electrode was 29 layers.
  • separator 1 As a separator, separator 1 (thickness: 25 ⁇ m, porosity 56%) including a porous resin layer made of polyethylene terephthalate (PET) and a ceramic layer made of boehmite particles was used.
  • PET polyethylene terephthalate
  • the physical properties of the separator 1 are as follows. Tensile elongation in the MD direction: 20% Tensile elongation in the TD direction: 19% Average value of tensile elongation in MD direction and tensile elongation in TD direction: 19.5% Melting point: 250 ° C
  • Constant current charge to 4.2 V Constant current charge to 4.2 V, and then constant voltage charge to a charge termination current of 0.015 C at a constant voltage of 4.2 V to make a full charge state.
  • an SUS304 nail manufactured by Hakusui Mfg. Co., Ltd.
  • a nailing test was conducted in which the sheet was pierced in a direction perpendicular to the surface to short the laminated type laminated battery.
  • the laminate battery is short-circuit discharged, and the voltage is in the range of 0.001 V or more and 0.100 V or less, compared with a laminated type laminate battery manufactured by Yokogawa Meter & Instruments.
  • a resistance measuring instrument product name: Digital Multimeter 7544-01
  • a tester was applied to the positive electrode terminal and the negative electrode terminal at 25 ° C. to measure the direct current resistance between the positive and negative electrodes at room temperature (25 ° C.).
  • Cycle Test The cycle characteristics of the obtained laminate type laminated battery were evaluated.
  • the capacity retention rate (%) is a value obtained by dividing the discharge capacity (mAh) after 300 cycles by the discharge capacity (mAh) at the 10th cycle. Those with a capacity retention rate (%) of 80% or more were rated as ⁇ , and those with less than 80% were rated as ⁇ .
  • Safety test A SUS304 nail (manufactured by Hakusui Mfg. Co., Ltd.) with a diameter of 3 mm and a length of 70 mm is made at 80 mm / sec under an environment of 25 ° C. against the central part of a fully charged laminate type laminated battery. The laminate was pierced in a direction perpendicular to the electrode surface at a speed of 1 to short the laminated type laminate battery. Next, the condition of the battery after 6 hours was observed, and the safety of the battery was evaluated based on the following criteria. ⁇ : Both smoke and ignition did not occur from lithium ion battery. ⁇ : At least one of smoke and ignition occurred from lithium ion battery.
  • Example 1 the voltage of the laminate battery when the DC resistance between the positive and negative electrodes was measured was 0.0582 V.
  • Example 2 As the separator, lamination was performed in the same manner as in Example 1 except that a separator 2 made of a porous resin layer (thickness: 15 ⁇ m, porosity 65%) composed of a wholly aromatic polyamide (also referred to as aramid) was used. Type laminated battery was produced and each evaluation was performed.
  • the physical properties of the separator 2 are as follows.
  • Example 3 A laminated laminate battery was prepared in the same manner as in Example 2 except that the composition ratio of the positive electrode was changed to 95.0 parts by mass of the positive electrode active material, 2.0 parts by mass of the conductive additive, and 3.0 parts by mass of the binder resin. It produced and performed each evaluation.
  • the voltage of the laminate battery when the DC resistance between the positive and negative electrodes was measured was 0.0582 V.
  • Example 1 A laminated laminate battery was prepared in the same manner as in Example 1 except that the composition ratio of the positive electrode was changed to 93.0 parts by mass of the positive electrode active material, 4.0 parts by mass of the conductive additive, and 3.0 parts by mass of the binder resin. It produced and performed each evaluation.
  • Example 2 A laminate type laminate battery is prepared in the same manner as in Example 1 except that a separator 3 (thickness: 25 ⁇ m, porosity 54%) including a porous resin layer made of polypropylene and a ceramic layer (alumina) is used as a separator. Were made, and each evaluation was performed.
  • the physical properties of the separator 3 are as follows. Tensile elongation in the MD direction: 125% Tensile elongation in the TD direction: 630% Average value of tensile elongation in MD direction and tensile elongation in TD direction: 377.5% Melting point: 160 ° C
  • Example 3 A laminated laminate battery is produced in the same manner as in Example 1 except that a separator 4 made of a porous resin layer (thickness: 25 ⁇ m, porosity: 55%) made of polypropylene is used as a separator, and each evaluation is shown went.
  • the physical properties of the separator 4 are as follows. Tensile elongation in the MD direction: 50% Tensile elongation in the TD direction: 400% Average value of tensile elongation in MD direction and tensile elongation in TD direction: 225% Melting point: 160 ° C
  • Example 4 Example 1 except that a separator 5 comprising a porous resin layer made of polypropylene (thickness: 18 ⁇ m, porosity: 54%) and a ceramic layer made of alumina (thickness: 7 ⁇ m) was used as a separator
  • a laminated laminate battery was produced in the same manner as in the above, and each evaluation was performed.
  • the physical properties of the separator 5 are as follows. Tensile elongation in the MD direction: 50% Tensile elongation in the TD direction: 400% Average value of tensile elongation in MD direction and tensile elongation in TD direction: 225% Melting point: 160 ° C
  • Example 5 Lamination was carried out in the same manner as in Example 1 except that a separator 6 comprising a non-woven fabric layer made of glass fiber and a layer made of ceramics (magnesium oxide) (thickness: 30 ⁇ m, porosity: 76%) was used as a separator.
  • Type laminated battery was produced and each evaluation was performed.
  • the physical properties of the separator 6 are as follows. Tensile elongation in the MD direction: 8.9% Tensile elongation in the TD direction: 14.3% Average value of tensile elongation in MD direction and tensile elongation in TD direction: 11.6%
  • Example 6 A laminated laminate battery was prepared in the same manner as in Example 1 except that the compounding ratio of the positive electrode was changed to 96.0 parts by mass of the positive electrode active material, 1.0 part by mass of the conductive additive, and 3.0 parts by mass of the binder resin. It produced and performed each evaluation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Secondary Cells (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Cell Separators (AREA)

Abstract

Une batterie secondaire au lithium-ion selon la présente invention comprend un boîtier qui stocke : une électrode positive ayant une couche de collecteur d'électrode positive et une couche de matériau actif d'électrode positive ; une électrode négative ayant une couche de collecteur d'électrode négative et une couche de matériau actif d'électrode négative ; une solution électrolytique non aqueuse contenant un sel de lithium ; et un séparateur interposé entre l'électrode positive et l'électrode négative. La batterie secondaire au lithium-ion est soumise à une décharge de court-circuit après un test de pénétration de clou, qui est conduit pour court-circuiter la batterie secondaire au lithium-ion dans un état complètement chargé à une température de 25 °C en amenant un clou fait de SUS 304 avec un diamètre φ de 3 mm et une longueur de 70 mm à pénétrer dans le centre de la batterie secondaire au lithium-ion à une vitesse de 80 mm/sec. Lorsque la tension est de 0,001 V à 100 V inclus, la résistance CC entre les électrodes positive et négative dans la batterie secondaire au lithium-ion est de 0,1 Ω à 300 Ω inclus.
PCT/JP2017/037184 2017-10-13 2017-10-13 Batterie secondaire au lithium-ion WO2019073595A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN201780095520.7A CN111164817B (zh) 2017-10-13 2017-10-13 锂离子二次电池
PCT/JP2017/037184 WO2019073595A1 (fr) 2017-10-13 2017-10-13 Batterie secondaire au lithium-ion
JP2019547880A JPWO2019073595A1 (ja) 2017-10-13 2017-10-13 リチウムイオン二次電池

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2017/037184 WO2019073595A1 (fr) 2017-10-13 2017-10-13 Batterie secondaire au lithium-ion

Publications (1)

Publication Number Publication Date
WO2019073595A1 true WO2019073595A1 (fr) 2019-04-18

Family

ID=66100528

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2017/037184 WO2019073595A1 (fr) 2017-10-13 2017-10-13 Batterie secondaire au lithium-ion

Country Status (3)

Country Link
JP (1) JPWO2019073595A1 (fr)
CN (1) CN111164817B (fr)
WO (1) WO2019073595A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112750978A (zh) * 2020-12-30 2021-05-04 珠海冠宇电池股份有限公司 极片及电池

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113937415A (zh) * 2020-06-28 2022-01-14 华为技术有限公司 二次电池和终端
CN113809278B (zh) * 2021-09-15 2023-05-16 珠海冠宇电池股份有限公司 一种电极组件及其应用

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10199574A (ja) * 1996-12-28 1998-07-31 Japan Storage Battery Co Ltd 非水電解液電池
JP2006019191A (ja) * 2004-07-02 2006-01-19 Japan Vilene Co Ltd リチウムイオン二次電池用セパレータ及びリチウムイオン二次電池
WO2007136206A1 (fr) * 2006-05-22 2007-11-29 Lg Chem, Ltd. Pile rechargeable à électrode accroissant la stabilité en cas de surrecharge
JP2017033826A (ja) * 2015-08-04 2017-02-09 オートモーティブエナジーサプライ株式会社 リチウムイオン二次電池
JP2017188576A (ja) * 2016-04-06 2017-10-12 日本バイリーン株式会社 電気化学素子用セパレータ

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7332242B2 (en) * 2000-09-01 2008-02-19 Itochu Corporation Lithium-based battery having extensible, ion-impermeable polymer covering on the battery container
KR100611940B1 (ko) * 2003-11-21 2006-08-11 주식회사 엘지화학 안전성이 향상된 전기화학 전지
JP2005285385A (ja) * 2004-03-29 2005-10-13 Sanyo Electric Co Ltd セパレータ及びこのセパレータを用いた非水電解質電池
JP5331333B2 (ja) * 2007-01-16 2013-10-30 パナソニック株式会社 非水電解質二次電池
JP2009032682A (ja) * 2007-06-28 2009-02-12 Hitachi Maxell Ltd リチウムイオン二次電池
JP5378720B2 (ja) * 2007-07-27 2013-12-25 パナソニック株式会社 リチウムイオン二次電池
JP5497635B2 (ja) * 2007-08-31 2014-05-21 東レバッテリーセパレータフィルム株式会社 ポリオレフィン微多孔膜、その製造方法、電池用セパレータ及び電池
JP2011243558A (ja) * 2010-04-22 2011-12-01 Hitachi Maxell Energy Ltd リチウム二次電池用正極およびリチウム二次電池
JP4868556B2 (ja) * 2010-04-23 2012-02-01 日立マクセルエナジー株式会社 リチウム二次電池
JPWO2017013827A1 (ja) * 2015-07-22 2018-05-10 株式会社豊田自動織機 リチウムイオン二次電池

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10199574A (ja) * 1996-12-28 1998-07-31 Japan Storage Battery Co Ltd 非水電解液電池
JP2006019191A (ja) * 2004-07-02 2006-01-19 Japan Vilene Co Ltd リチウムイオン二次電池用セパレータ及びリチウムイオン二次電池
WO2007136206A1 (fr) * 2006-05-22 2007-11-29 Lg Chem, Ltd. Pile rechargeable à électrode accroissant la stabilité en cas de surrecharge
JP2017033826A (ja) * 2015-08-04 2017-02-09 オートモーティブエナジーサプライ株式会社 リチウムイオン二次電池
JP2017188576A (ja) * 2016-04-06 2017-10-12 日本バイリーン株式会社 電気化学素子用セパレータ

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
SUDO, SHINYA ET AL.: "Review on nail penetration test of lithium ion battery: (1) - short circuit resistance analysis", LECTURE ABSTRACTS OF 57TH BATTERY SYMPOSIUM IN JAPAN, vol. 1C19, 28 November 2016 (2016-11-28), pages 170 *
ZHAO, WEI ET AL.: "Modeling Nail Penetration Process in Large-Format Li- Ion Cells", JOURNAL OF THE ELECTROCHEMICAL SOCIETY, vol. 162, no. 1, 3 December 2014 (2014-12-03), pages A207 - A217, XP055593322, DOI: 10.1149/2.1071501jes *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112750978A (zh) * 2020-12-30 2021-05-04 珠海冠宇电池股份有限公司 极片及电池

Also Published As

Publication number Publication date
CN111164817B (zh) 2023-09-01
CN111164817A (zh) 2020-05-15
JPWO2019073595A1 (ja) 2020-10-22

Similar Documents

Publication Publication Date Title
JP6398985B2 (ja) リチウムイオン二次電池
JP5264099B2 (ja) 非水電解質二次電池
JP6560879B2 (ja) リチウムイオン二次電池用正極、及びリチウムイオン二次電池
JP2008300302A (ja) 非水電解質二次電池及び非水電解質二次電池用正極の製造方法
WO2016113863A1 (fr) Batterie à électrolyte non aqueux et bloc-batterie
CN110546809B (zh) 包括用于加速热传导的密封带的电池单体
JP7247353B2 (ja) 電極、電池、及び電池パック
CN111164817B (zh) 锂离子二次电池
JP2019175657A (ja) リチウムイオン二次電池。
JP2016139548A (ja) リチウムイオン電池
JP2020068123A (ja) 電池
WO2015129376A1 (fr) Ensemble d'électrodes laminé et batterie à électrolyte non aqueux
JP2019164965A (ja) リチウムイオン二次電池
JP2015128052A (ja) 蓄電素子
JP7003775B2 (ja) リチウムイオン二次電池
CN112335091B (zh) 锂离子二次电池
JP6658182B2 (ja) 電極構造体及びリチウム二次電池
JP6928738B2 (ja) リチウムイオン電池
JP2021077531A (ja) 非水電解質二次電池
CN112335092B (zh) 锂离子二次电池
JP2020004655A (ja) リチウムイオン電池の製造方法
CN111029580B (zh) 二次电池用电极和二次电池
WO2023106099A1 (fr) Batterie
JPWO2017094719A1 (ja) リチウムイオン二次電池
JP2017037744A (ja) 非水電解質二次電池

Legal Events

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

Ref document number: 17928718

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2019547880

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17928718

Country of ref document: EP

Kind code of ref document: A1