WO2018123479A1 - Lithium ion cell and method for manufacturing same - Google Patents

Lithium ion cell and method for manufacturing same Download PDF

Info

Publication number
WO2018123479A1
WO2018123479A1 PCT/JP2017/043748 JP2017043748W WO2018123479A1 WO 2018123479 A1 WO2018123479 A1 WO 2018123479A1 JP 2017043748 W JP2017043748 W JP 2017043748W WO 2018123479 A1 WO2018123479 A1 WO 2018123479A1
Authority
WO
WIPO (PCT)
Prior art keywords
solid electrolyte
layer
lithium ion
electrode layer
positive electrode
Prior art date
Application number
PCT/JP2017/043748
Other languages
French (fr)
Japanese (ja)
Inventor
吉田　俊広
Original Assignee
日本碍子株式会社
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 日本碍子株式会社 filed Critical 日本碍子株式会社
Priority to JP2018558965A priority Critical patent/JP7009390B2/en
Publication of WO2018123479A1 publication Critical patent/WO2018123479A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
    • 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
    • H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
    • H01M10/0562—Solid materials
    • 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
    • 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
    • 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 battery and a method for manufacturing the same.
  • the lithium ion battery includes a positive electrode layer including a positive electrode active material, a negative electrode layer including a negative electrode active material, and a solid electrolyte layer including an ion conductor.
  • Patent Document 1 it is proposed to use a solid electrolyte layer material containing an ion conductor with a controlled particle size ratio and a sintering aid in order to lower the firing temperature to 700 ° C.
  • the content of the sintering aid relative to the ionic conductor is suppressed to 3.5 wt% or less. ing.
  • Patent Document 1 attempts to improve the ionic conductivity by increasing the content of the ionic conductor in the solid electrolyte layer.
  • the internal resistance is reduced.
  • new knowledge was obtained that it is more advantageous to expand the ion-conducting region by lowering the porosity of the solid electrolyte layer, rather than increasing the content of the ionic conductor.
  • the present invention has been made based on the above-described knowledge, and an object thereof is to provide a lithium ion battery capable of reducing internal resistance and a method for manufacturing the lithium ion battery.
  • the lithium ion battery according to the present invention includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer.
  • the solid electrolyte layer contains a first solid electrolyte that is a main component and a second solid electrolyte that is a subcomponent.
  • the average porosity of the solid electrolyte layer is 9% or less.
  • the present invention it is possible to provide a lithium ion battery capable of reducing internal resistance and a manufacturing method thereof.
  • FIG. 1 is a cross-sectional view schematically showing the configuration of the lithium ion battery 100.
  • the chip-type lithium ion battery 100 configured in a plate shape is a secondary battery (rechargeable battery) that can be repeatedly used by charging and discharging.
  • the lithium ion battery 100 includes a positive electrode side current collecting layer 101, a negative electrode side current collecting layer 102, exterior materials 103 and 104, a current collecting connection layer 105, a positive electrode layer 106, a solid electrolyte layer 107, and a negative electrode layer 108.
  • the positive electrode side current collecting layer 101, the current collecting connection layer 105, the positive electrode layer 106, the solid electrolyte layer 107, the negative electrode layer 108, and the negative electrode side current collecting layer 102 are sequentially laminated in the laminating direction X.
  • the positive electrode part 110 is constituted by the positive electrode side current collecting layer 101, the current collecting connection layer 105 and the positive electrode layer 106.
  • the negative electrode side current collecting layer 102 and the negative electrode layer 108 constitute a negative electrode portion 120.
  • Positive electrode side current collecting layer 101 The positive electrode side current collecting layer 101 is disposed outside the positive electrode layer 106. The positive electrode side current collecting layer 101 is mechanically and electrically connected to the positive electrode layer 106 through the current collecting connection layer 105. The positive electrode side current collecting layer 101 functions as a positive electrode current collector.
  • the positive electrode side current collecting layer 101 can be made of metal.
  • the metal constituting the positive electrode side current collecting layer 101 include stainless steel, aluminum, copper, platinum, nickel and the like, and aluminum, nickel and stainless steel are particularly preferable.
  • the positive current collecting layer 101 can be formed in a plate shape or a foil shape, and a foil shape is particularly preferable. Therefore, it is particularly preferable to use an aluminum foil, a nickel foil, or a stainless steel foil as the positive electrode side current collecting layer 101.
  • the thickness of the positive electrode side current collecting layer 101 can be 1 ⁇ m or more and 30 ⁇ m or less, preferably 5 ⁇ m or more and 25 ⁇ m or less, and more preferably 10 ⁇ m or more and 20 ⁇ m or less.
  • Negative electrode side current collecting layer 102 The negative electrode side current collecting layer 102 is disposed outside the negative electrode layer 108. The negative electrode side current collecting layer 102 is mechanically and electrically connected to the negative electrode layer 108. The negative electrode side current collecting layer 102 functions as a negative electrode current collector.
  • the negative electrode side current collection layer 102 can be comprised with a metal.
  • the negative electrode side current collecting layer 102 can be made of the same material as that of the positive electrode side current collecting layer 101. Therefore, it is particularly preferable to use an aluminum foil, a nickel foil, or a stainless steel foil as the negative electrode side current collecting layer 102.
  • the thickness of the negative electrode side current collecting layer 102 can be 1 ⁇ m or more and 30 ⁇ m or less, preferably 5 ⁇ m or more and 25 ⁇ m or less, and more preferably 10 ⁇ m or more and 20 ⁇ m or less.
  • Exterior material 103, 104 The exterior materials 103 and 104 seal a gap between the positive electrode side current collecting layer 101 and the negative electrode side current collecting layer 102.
  • the packaging materials 103 and 104 surround the side of the unit cell constituted by the positive electrode layer 106, the solid electrolyte layer 107, and the negative electrode layer 108.
  • the exterior materials 103 and 104 suppress moisture intrusion into the lithium ion battery 100.
  • the resistivity of the exterior materials 103 and 104 is preferably 1 ⁇ 10 6 ⁇ cm or more, and preferably 1 ⁇ 10 7 ⁇ cm or more in order to ensure electrical insulation between the positive electrode side current collection layer 101 and the negative electrode side current collection layer 102. Is more preferably 1 ⁇ 10 8 ⁇ cm or more.
  • Such exterior material 103,104 can be comprised with an electrically insulating sealing material.
  • As the sealing material a resin-based sealing material containing a resin can be used. By using the resin-based sealing material, the exterior materials 103 and 104 can be formed at a relatively low temperature (for example, 400 ° C. or lower), so that the destruction and deterioration of the lithium ion battery 100 due to heating can be suppressed.
  • the exterior materials 103 and 104 can be formed by laminating resin films or dispensing liquid resin.
  • the current collecting connection layer 105 is disposed between the positive electrode layer 106 and the positive electrode side current collecting layer 101.
  • the current collecting connection layer 105 mechanically bonds the positive electrode layer 106 to the positive electrode side current collecting layer 101 and electrically bonds the positive electrode layer 106 to the positive electrode side current collecting layer 101.
  • the current collecting connection layer 105 includes a conductive material and an adhesive.
  • conductive material conductive carbon or the like can be used.
  • adhesive an epoxy-based resin material can be used.
  • the thickness of the current collector connection layer 105 is not particularly limited, but can be 5 ⁇ m or more and 100 ⁇ m or less, and preferably 10 ⁇ m or more and 50 ⁇ m or less.
  • the current collecting connection layer 105 may not contain an adhesive.
  • an electrical connection between the current collector connection layer 105 and the positive electrode layer 106 can be obtained by directly forming the current collector connection layer 105 (eg, gold or aluminum) on the back surface of the positive electrode layer 106.
  • Positive electrode layer 106 The positive electrode layer 106 is formed into a plate shape.
  • the positive electrode layer 106 has a solid electrolyte side surface 106a and a current collecting connection layer side surface 106b.
  • the positive electrode layer 106 is connected to the solid electrolyte layer 107 on the solid electrolyte side surface 106a.
  • the positive electrode layer 106 is connected to the current collector connection layer 105 on the current collector connection layer side surface 106b.
  • Each of the solid electrolyte side surface 106 a and the current collecting connection layer side surface 106 b is a “plate surface” of the positive electrode layer 106.
  • the solid electrolyte side surface 106a is a line obtained by linearly approximating the interface between the positive electrode layer 106 and the solid electrolyte layer 107 by the least square method when a cross section of the positive electrode layer 106 is observed with a scanning electron microscope (SEM). It is prescribed by.
  • the current collecting connection layer side surface 106b is defined by a line obtained by linear approximation of the interface between the positive electrode layer 106 and the current collecting connection layer 105 by the least square method when the cross section of the positive electrode layer 106 is observed by SEM.
  • the thickness of the positive electrode layer 106 is not particularly limited, but is preferably 20 ⁇ m or more, more preferably 25 ⁇ m or more, and further preferably 30 ⁇ m or more. In particular, by setting the thickness of the positive electrode layer 106 to 50 ⁇ m or more, the active material capacity per unit area can be sufficiently secured and the energy density of the lithium ion battery 100 can be increased.
  • the upper limit value of the thickness of the positive electrode layer 106 is not particularly limited, but is preferably less than 200 ⁇ m and more preferably 150 ⁇ m or less in consideration of suppression of deterioration of battery characteristics (particularly increase in resistance value) due to repeated charge / discharge. 120 ⁇ m or less is more preferable, and 100 ⁇ m or less is particularly preferable.
  • the expansion / contraction rate in a direction parallel to the plate surface of the positive electrode layer 106 is preferably suppressed to 0.7% or less.
  • plate surface direction The expansion / contraction rate in a direction parallel to the plate surface of the positive electrode layer 106.
  • the positive electrode layer 106 is preferably a sintered plate configured by combining a plurality of positive electrode active material crystal grains (primary particles).
  • the thickness can be increased as compared with the film formed by the vapor phase method, the capacity and energy density of the lithium ion battery 100 can be improved.
  • the composition of the positive electrode layer 106 can be adjusted by weighing the raw materials, the composition can be controlled with higher accuracy than a film formed by a vapor phase method.
  • the positive electrode active material crystal grains are mainly formed in a plate shape, but may include those formed in a rectangular parallelepiped shape, a cubic shape, a spherical shape, or the like.
  • the positive electrode active material crystal grains are composed of a lithium composite oxide.
  • the lithium composite oxide is Li x MO 2 (0.05 ⁇ x ⁇ 1.10, M is at least one transition metal, and M is typically one of Co, Ni, and Mn. Including the above.)
  • the lithium composite oxide has a layered rock salt structure.
  • the layered rock salt structure is a crystal structure in which lithium layers and transition metal layers other than lithium are alternately stacked with oxygen layers in between, that is, the transition metal ion layers and lithium single layers are alternately arranged via oxide ions. (Typically an ⁇ -NaFeO 2 type structure, ie, a structure in which transition metals and lithium are regularly arranged in the [111] axis direction of a cubic rock salt type structure).
  • lithium composite oxide examples include Li x CoO 2 (lithium cobaltate), Li x NiO 2 (lithium nickelate), Li x MnO 2 (lithium manganate), and Li x NiMnO 2 (nickel / lithium manganate).
  • the lithium composite oxide includes Mg, Al, Si, Ca, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ag, Sn, Sb, Te. , Ba, Bi, W, etc. may contain one or more elements.
  • the positive electrode active material crystal grains are preferably oriented in the lithium ion conduction direction.
  • the (003) plane of the positive electrode active material crystal grains is preferably oriented in the stacking direction X.
  • Solid electrolyte layer 107 contains a first solid electrolyte that is a main component and a second solid electrolyte that is a subcomponent.
  • the first solid electrolyte may be a base material
  • the second solid electrolyte may be an additive.
  • the first solid electrolyte is an oxide ceramic material having lithium ion conductivity.
  • the oxide ceramic material as the first solid electrolyte is at least one selected from the group consisting of garnet ceramic materials, nitride ceramic materials, perovskite ceramic materials, phosphate ceramic materials, and zeolite materials. be able to.
  • garnet-based ceramic materials include Li—La—Zr—O materials (specifically, Li 7 La 3 Zr 2 O 12 and the like) and Li—La—Ta—O materials (specifically, Li 7 La 3 Ta 2 O 12 etc.).
  • nitride-based ceramic materials include Li 3 N and LiPON (specifically, Li x PO y N z (2 ⁇ x ⁇ 4, 3 ⁇ y ⁇ 5, 0.1 ⁇ z ⁇ 0.9)) ) And the like.
  • perovskite ceramic materials examples include Li—La—Ti—O materials (specifically, LiLa 1-x Ti x O 3 (0.04 ⁇ x ⁇ 0.14)).
  • Examples of phosphoric acid-based ceramic materials include Li—Al—Ti—P—O materials (specifically, Li (Al, Ti) 2 (PO 4 ) 3 ), Li—Al—Ge—PO materials. (Specifically, Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 etc.), and Li—Al—Ti—Si—P—O materials (specifically, Li 1 + x + y Al x Ti 2-x Si y P 3-y O 12 (0 ⁇ x ⁇ 0.4,0 ⁇ y ⁇ 0.6) , and the like).
  • the average content of the first solid electrolyte in the solid electrolyte layer 107 can be 70 wt% or more and 96 wt% or less.
  • the average content of the first solid electrolyte is determined by measuring the content of the first solid electrolyte at four locations in the cross section of the solid electrolyte layer 107 that equally divide the solid electrolyte layer 107 into five in the thickness direction (same as the stacking direction X). Is obtained by arithmetically averaging it.
  • the content rate of the first solid electrolyte in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
  • EDS energy dispersive X-ray spectrometer
  • the second solid electrolyte is an oxide-based ceramic material, a plastic material, or a combination thereof.
  • the second solid electrolyte may have lithium ion conductivity or may not have lithium ion conductivity.
  • the lithium ion conductivity of the second solid electrolyte may be lower than the lithium ion conductivity of the first solid electrolyte.
  • the oxide-based ceramic material as the second solid electrolyte includes a general formula Li x AO y (where A is B, C, Cl, Al, Si, P, S, Ti, Zr, Nb) , Mo, Ta, or W, and x and y are positive integers).
  • Examples include at least one selected from the group consisting of TiO 3 , Li 4 Ti 5 O 12 , Li 2 Ti 2 O 5 , Li 2 ZrO 3 , LiNbO 3 , Li 2 MoO 4 , and Li 2 WO 4 .
  • the solid electrolyte layer 107 can be produced by a sintering method.
  • the second solid electrolyte functions as a sintering aid that promotes liquid phase sintering of the first solid electrolyte.
  • the melting point of the oxide-based ceramic material that is the second solid electrolyte is preferably 600 ° C. or lower.
  • the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 4 wt% or more, more preferably 10 wt% or more, and particularly preferably 15 wt% or more. Accordingly, the second solid electrolyte can be sufficiently filled in the gap between the liquid-phase sintered first solid electrolyte, so that the solid electrolyte layer 107 can be densified as described later.
  • the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 30 wt% or less, more preferably 25 wt% or less, and particularly preferably 20 wt% or less. . Thereby, even if the lithium ion conductivity of the second solid electrolyte is low, the lithium ion conductivity of the solid electrolyte layer 107 as a whole can be maintained.
  • the average content of the oxide-based ceramic material as the second solid electrolyte in the solid electrolyte layer 107 is the oxide-based ceramic material at four locations where the solid electrolyte layer 107 is equally divided into five in the thickness direction in the cross section of the solid electrolyte layer 107. It is obtained by measuring the content of and averaging it. The content of the oxide-based ceramic material at each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
  • EDS energy dispersive X-ray spectrometer
  • plastic material As the plastic material as the second solid electrolyte, glass material, lithium aluminum hexafluoride (Li 3 AlF 6 ), NaI—LiBH 4 or the like can be used.
  • the glass material Bi 2 O 3 , B 2 O 3 , or a mixture thereof can be used.
  • the solid electrolyte layer 107 can be produced by heating a mixture of the first solid electrolyte and the second solid electrolyte to a temperature above the softening point of the second solid electrolyte.
  • the glass material that is the second solid electrolyte spreads in the gaps of the first solid electrolyte by plastic deformation.
  • the softening point of the second solid electrolyte is preferably 600 ° C. or lower. Thereby, it is possible to prevent the active material in the positive electrode layer 106 or the negative electrode layer 108 from reacting with the first or second solid electrolyte to form a high resistance layer.
  • Li 3 AlF 6 and / or NaI-LiBH 4 is used as the second solid electrolyte
  • a mixture of the first solid electrolyte and the second solid electrolyte is deposited using an electrophoretic deposition (EPD) method.
  • the solid electrolyte layer 107 can be produced by applying pressure.
  • Li 3 AlF 6 and NaI—LiBH 4 that are the second solid electrolytes spread in the gaps of the first solid electrolyte by plastic deformation. Since Li 3 AlF 6 and NaI—LiBH 4 have plasticity at 20 ° C. or higher, the solid electrolyte layer 107 can be formed without heating. Therefore, it can suppress that the active material in the positive electrode layer 106 or the negative electrode layer 108 and the 1st or 2nd solid electrolyte react, and a high resistance layer is formed.
  • the second solid electrolyte when the second solid electrolyte has deliquescence, it is effective to increase the atmospheric humidity when the mixture of the first solid electrolyte and the second solid electrolyte is pressurized. As a result, a good interface can be formed between the positive electrode layer 106 and the solid electrolyte layer 107.
  • the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 4 wt% or more, more preferably 10 wt% or more, and particularly preferably 15 wt% or more. Thereby, the gap between the first solid electrolytes can be sufficiently filled with the second solid electrolyte, so that the solid electrolyte layer 107 can be densified.
  • the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 30 wt% or less, more preferably 25 wt% or less, and particularly preferably 20 wt% or less.
  • the average content of the plastic material in the solid electrolyte layer 107 is obtained by measuring the content of the plastic material at four locations where the solid electrolyte layer 107 is equally divided into five in the thickness direction in the cross section of the solid electrolyte layer 107, and arithmetically averaging them. Can be obtained.
  • the content rate of the plastic material in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
  • the average porosity of the solid electrolyte layer 107 is 9% or less. That is, the average density of the solid electrolyte layer 107 is 91% or more. In this way, the ionic conductivity of the solid electrolyte layer 107 can be improved more than increasing the content of the ionic conductor by widening the ion conductive region by sufficiently reducing the average porosity of the solid electrolyte layer 107. Therefore, the internal resistance of the lithium ion battery 100 can be reduced.
  • the average porosity of the solid electrolyte layer 107 is preferably 7% or less, and particularly preferably 5% or less.
  • the average porosity of the solid electrolyte layer 107 is obtained by measuring the porosity at four locations in the cross section of the solid electrolyte layer 107 that equally divide the solid electrolyte layer 107 into five in the thickness direction, and arithmetically averaging them.
  • the porosity is calculated by obtaining an SEM (electron microscope) image at 20000 magnification at each measurement location, and dividing the total area of the pores in the solid electrolyte layer 107 by the area of the entire solid electrolyte layer 107.
  • the solid electrolyte layer 107 does not substantially contain sulfur.
  • substantially containing no sulfur means that the average content of sulfur in the solid electrolyte layer 107 is 0.1 wt% or less. Accordingly, it is possible to suppress generation of toxic gas from the solid electrolyte layer 107 when moisture enters from the outside of the lithium ion battery 100.
  • the average content of sulfur in the solid electrolyte layer 107 is more preferably 0.01 wt% or less, and particularly preferably 0.001 wt% or less.
  • the average content of sulfur in the solid electrolyte layer 107 is obtained by measuring the sulfur content at four locations that divide the solid electrolyte layer 107 into 5 parts in the thickness direction in the cross section of the solid electrolyte layer 107 and arithmetically averaging them. can get.
  • the sulfur content in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
  • EDS energy dispersive X-ray spectrometer
  • the thickness of the solid electrolyte layer 107 is preferably thin from the viewpoint of improving lithium ion conductivity, but is set as appropriate in consideration of reliability during charge / discharge (suppression of defects and cracks, function as a separator, etc.). can do.
  • the thickness of the solid electrolyte layer 107 can be, for example, 1 ⁇ m or more and 1000 ⁇ m or less.
  • the thickness of the solid electrolyte layer 107 is preferably 10 ⁇ m or more and 500 ⁇ m or less, and particularly preferably 20 ⁇ m or more and 200 ⁇ m or less.
  • Negative electrode layer 108 The negative electrode layer 108 is disposed on the solid electrolyte layer 107.
  • the negative electrode layer 108 contains a negative electrode active material.
  • the negative electrode active material may be any material that can occlude and release lithium ions.
  • As the negative electrode active material for example, a carbonaceous material or a lithium storage material can be used.
  • the carbonaceous material examples include graphite, pyrolytic carbons, cokes, glassy carbons, fired bodies of organic polymer compounds, mesocarbon microbeads, carbon fibers, and activated carbon.
  • a part of graphite may be replaced with a metal or an oxide that can be alloyed with lithium.
  • the thickness of the negative electrode layer 108 can be 10 ⁇ m or more and 500 ⁇ m or less.
  • the lithium storage material examples include metallic lithium, alloys containing metallic lithium and other elements (silicon, tin, indium, etc.), oxides such as silicon or tin that can be charged and discharged at a low potential close to lithium, Li 4 Ti 5 O
  • examples thereof include an oxide of lithium and titanium such as 12 (LTO), a nitride of lithium and cobalt such as Li 2.6 Co 0.4 N, and TiO 2 (titania).
  • the negative electrode layer 108 may be composed of sintered plate by a plurality of anode active material crystal grains (primary particles) binds.
  • the composition formula of the lithium occlusion material naturally changes according to the occlusion and release of lithium ions.
  • the thickness of the negative electrode layer 108 can be 10 ⁇ m or more and 500 ⁇ m or less.
  • the negative electrode layer 108 is preferably manufactured by the EPD method. As a result, the negative electrode layer 108 can be fabricated at a lower temperature than in the sputtering method, the CVD method, or the like. Therefore, the active material in the negative electrode layer 108 reacts with the first or second solid electrolyte in the solid electrolyte layer 107 to increase resistance. Formation of a layer can be suppressed.
  • the negative electrode layer 108 may be formed by a tape molding method, a printing method, a spin coating method, or the like depending on the material of the negative electrode layer 108.
  • a foil-like lithium storage member (such as Sn foil or Li foil) can be used for the negative electrode layer 108.
  • the negative electrode layer 108 can be produced by press-molding a foil-like lithium occlusion member on the solid electrolyte layer 107. Also in this case, it can be suppressed that the active material in the negative electrode layer 108 reacts with the first or second solid electrolyte in the solid electrolyte layer 107 to form a high resistance layer.
  • the positive electrode layer 106 (an example of the first electrode) is composed of the positive electrode active material crystal grains, but in addition to the positive electrode active material, the constituent material of the solid electrolyte layer 107 described above It is preferable to contain (first solid electrolyte and second solid electrolyte). As a result, the ion conductivity between the positive electrode layer 106 and the solid electrolyte layer 107 can be improved, so that the internal resistance of the lithium ion battery 100 can be reduced.
  • the total content of the first solid electrolyte and the second solid electrolyte in the positive electrode layer 106 is preferably 30 wt% or more, and the average content of the second solid electrolyte in the positive electrode layer 106 is preferably 4 wt% or more and 20 wt% or less.
  • the porosity of the positive electrode layer 106 can be 9% or less.
  • the total content of the first solid electrolyte and the second solid electrolyte in the positive electrode layer 106 is more preferably 40 wt% or more, and particularly preferably 50 wt% or more.
  • the average content of the second solid electrolyte in the positive electrode layer 106 is more preferably 5 wt% or more and 15 wt% or less, and particularly preferably 7 wt% or more and 12 wt% or less.
  • the positive electrode layer 106 containing the constituent materials (the first solid electrolyte and the second solid electrolyte) of the solid electrolyte layer 107 can be produced in the same manner as the solid electrolyte layer 107.
  • the negative electrode layer 108 (an example of the first electrode) can be composed of a negative electrode active material such as a carbonaceous material or a lithium storage material.
  • the solid electrolyte described above is used. It is preferable that the constituent materials of the layer 107 (first solid electrolyte and second solid electrolyte) are contained. Thereby, since the ion conductivity between the negative electrode layer 108 and the solid electrolyte layer 107 can be improved, the internal resistance of the lithium ion battery 100 can be reduced.
  • the total content of the first solid electrolyte and the second solid electrolyte in the negative electrode layer 108 is preferably 30 wt% or more, and the average content of the second solid electrolyte in the negative electrode layer 108 is preferably 4 wt% or more and 20 wt% or less.
  • the porosity of the negative electrode layer 108 can be reduced to 9% or less.
  • the total content of the first solid electrolyte and the second solid electrolyte in the negative electrode layer 108 is more preferably 40 wt% or more, and particularly preferably 50 wt% or more.
  • the average content of the second solid electrolyte in the negative electrode layer 108 is particularly preferably 10 wt% or more and 15 wt% or less.
  • the negative electrode layer 108 containing the constituent materials (the first solid electrolyte and the second solid electrolyte) of the solid electrolyte layer 107 can be manufactured in the same manner as the solid electrolyte layer 107.
  • the positive electrode layer 106 and the solid electrolyte layer 107 are in direct contact with each other.
  • the present invention is not limited to this.
  • a solid electrolyte oxide-based ceramic material, plastic material, or a combination thereof
  • One intermediate layer may be interposed.
  • the solid electrolyte constituting the first intermediate layer may be different from the second solid electrolyte contained in the solid electrolyte layer 107 as a subcomponent, but is preferably the same.
  • the thickness of the first intermediate layer is not particularly limited, and can be, for example, 1 ⁇ m or more and 5 ⁇ m or less. By interposing such a first intermediate layer, the adhesion between the positive electrode layer 106 and the solid electrolyte layer 107 is improved, so that the resistance between the positive electrode layer 106 and the solid electrolyte layer 107 can be reduced. .
  • the negative electrode layer 108 and the solid electrolyte layer 107 are in direct contact with each other.
  • the present invention is not limited to this.
  • a solid electrolyte oxide-based ceramic material, plastic material, or a combination thereof
  • Two intermediate layers may be interposed.
  • the solid electrolyte constituting the second intermediate layer may be different from the second solid electrolyte contained in the solid electrolyte layer 107 as a subcomponent, but is preferably the same.
  • the thickness of the second intermediate layer is not particularly limited, and can be, for example, 1 ⁇ m or more and 5 ⁇ m or less.
  • a known organic electrolytic solution may be interposed between the positive electrode layer 106 and the solid electrolyte layer 107. Thereby, the bondability between the positive electrode layer 106 and the solid electrolyte layer 107 can be improved.
  • a known organic electrolyte solution may be interposed between the negative electrode layer 108 and the solid electrolyte layer 107. Thereby, the bondability between the negative electrode layer 108 and the solid electrolyte layer 107 can be improved.
  • At least one of the positive electrode layer 106, the solid electrolyte layer 107, and the negative electrode layer 108 may contain a known organic electrolytic solution. Thereby, it is possible to improve the bonding property between the particles constituting the layer containing the organic electrolyte.
  • the content rate of the organic electrolyte solution in the layer containing the organic electrolyte solution is not particularly limited, it is preferably 9% or less because the organic electrolyte solution can be disposed in the pores.
  • the content of the organic electrolyte in the layer containing the organic electrolyte is obtained by measuring the content of the organic electrolyte at four locations that divide each layer into 5 parts in the thickness direction in the cross section of each layer, and arithmetically averaging it. can get.
  • the content rate of the organic electrolyte is calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the organic electrolyte in the SEM image by the area of the entire layer.
  • LiCoO 2 powder was pulverized to obtain plate-like LiCoO 2 particles (LCO template particles).
  • Co 3 O 4 (CoO) raw material powder manufactured by Shodo Chemical Industry Co., Ltd. was prepared as matrix particles.
  • the mixture was degassed by stirring under reduced pressure, and a slurry was prepared by adjusting the viscosity to 40960000 cP.
  • the green sheet peeled from the PET film was placed on a zirconia setter and subjected to primary firing to obtain a Co 3 O 4 sintered plate.
  • the Co 3 O 4 sintered plate was placed on a zirconia setter while being sandwiched between upper and lower lithium sheets and subjected to secondary firing to obtain a LiCoO 2 (LCO) sintered plate as a positive electrode layer.
  • the thickness of the LCO sintered plate was 50 ⁇ m.
  • Example 8 LATP was used as the main component, and Li 3 BO 3 was used as the subcomponent.
  • the subcomponents of Examples 1 to 8 are oxide ceramic materials. The mixing ratio of the subcomponents was changed between 3 and 40 wt% as shown in Table 1.
  • a solid electrolyte layer and a negative electrode layer were formed by collectively firing a laminate of a positive electrode layer, a solid electrolyte layer compact, and a negative electrode layer compact.
  • the thickness of the positive electrode layer was 50 ⁇ m.
  • the thickness of the solid electrolyte layer was 20 ⁇ m.
  • Example 1 since the melting point of Li 4 SiO 4 —Li 3 BO 3 which is a subcomponent is 550 ° C., the firing temperature was set to 600 ° C. In Example 7, since the melting point of LiPO 3 as the accessory component was 660 ° C., the firing temperature was 700 ° C. In Example 8, since the melting point of Li 3 BO 3 , which is a subcomponent, is 715 ° C., the firing temperature was 750 ° C.
  • Example 9 The same as in Examples 1 to 6 except that the laminate of the positive electrode layer and the molded body of the solid electrolyte layer was fired to form the solid electrolyte layer, and then the foil-shaped negative electrode layer was press-molded on the solid electrolyte layer.
  • Lithium ion batteries according to Examples 9 and 10 were produced according to the process.
  • Example 9 Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) was used as the main component of the solid electrolyte layer, and Li 4 SiO 4 —Li 3 BO 3 was used as the subcomponent. .
  • the main component and the subcomponent were mixed at a ratio of 70 wt%: 30 wt%.
  • Li 7 La 3 Zr 2 O 12 (LLZ) was used as the main component of the solid electrolyte layer, and Li 3 ClO was used as the subcomponent.
  • the main component and the subcomponent were mixed at a ratio of 90 wt%: 10 wt%. Since the melting point of Li 3 ClO is 350 ° C., the firing temperature in Example 10 was set to 350 ° C.
  • Example 11 The lithium ion battery according to Example 11 was manufactured in the same manner as in Example 10 except that the negative electrode layer was formed by printing a mixture of the carbon powder and the main component and subcomponent of the solid electrolyte layer on the solid electrolyte layer. Produced. In the negative electrode layer of Example 11, LLZ which is the main component of the carbon powder and the solid electrolyte layer and Li 3 ClO which is the subcomponent were mixed at a ratio of 50 wt%: 40 wt%: 10 wt%.
  • Example 12 Except that the solid electrolyte layer and the negative electrode layer were formed by collectively uniaxially pressing the molded body of the positive electrode layer, the solid electrolyte layer and the negative electrode layer (room temperature, 200 MPa), and A lithium ion battery according to Example 12 was fabricated by the same process.
  • Example 12 LAGP was used as the main component of the solid electrolyte layer, and Li 3 AlF 6 was used as the subcomponent.
  • the main component and the subcomponent were mixed at a ratio of 90 wt%: 10 wt%.
  • the accessory component of Example 12 is a plastic material.
  • Example 12 a compact of the solid electrolyte layer was formed by depositing a mixture of LAGP and Li 3 AlF 6 on the positive electrode layer using the EPD method. Further, a mixture of LTO powder and LAGP and Li 3 AlF 6, by depositing with the EPD method on molded article of the solid electrolyte layer to form a molded body of the negative electrode layer.
  • Example 13 A lithium ion battery according to Example 13 was fabricated by the same process as in Example 9, except that Bi 2 O 3 —B 2 O 3 (90 wt%: 10 wt%) was used as a subcomponent of the solid electrolyte layer.
  • Bi 2 O 3 —B 2 O 3 used as an accessory component is a plastic material. Since the softening point of Bi 2 O 3 —B 2 O 3 is 389 ° C., the heating temperature was set to 400 ° C.
  • Example 14 to 18 The lithium ion batteries according to Examples 14 to 18 were manufactured in the same manner as in Example 12 except that LAGP was used as the main component of the solid electrolyte layer and NaI-LiBH 4 (99 wt%: 1 wt%) was used as the subcomponent. Produced. NaI—LiBH 4 used as an accessory component is a plastic material.
  • Examples 14 to 18 a mixture of LAGP and NaI-LiBH 4 was deposited on the positive electrode layer using the EPD method, thereby forming a solid electrolyte layer compact. Further, a mixture of LTO powder and LAGP and NaI-LiBH 4, by depositing with the EPD method on molded article of the solid electrolyte layer to form a molded body of the negative electrode layer.
  • LTO powder, LAGP, which is the main component of the solid electrolyte layer, and NaI—LiBH 4 which is the subcomponent were mixed at a ratio of 50 wt%: 45 wt%: 5 wt%.
  • Example 19 A first intermediate layer (thickness 1 ⁇ m) composed of Li 4 SiO 4 —Li 3 BO 3 (30 wt%: 70 wt%), which is a subcomponent of the solid electrolyte layer, is interposed between the positive electrode layer and the solid electrolyte layer.
  • a lithium ion battery according to Example 19 was fabricated by the same process as in Example 2 except that it was inserted. However, in Example 19, an LTO sintered plate was used as the negative electrode layer.
  • Example 20 Between the positive electrode layer and the solid electrolyte layer, a first intermediate layer (thickness 2 ⁇ m) composed of Li 3 AlF 6 which is a subcomponent of the solid electrolyte layer is interposed, and between the negative electrode layer and the solid electrolyte layer, A lithium ion battery according to Example 20 was produced by the same process as Example 12 except that a second intermediate layer (thickness 2 ⁇ m) constituted by Li 3 AlF 6 which is a subcomponent of the solid electrolyte layer was interposed. . However, in Example 20, the main component and the subcomponent were mixed at a ratio of 70 wt%: 30 wt%, and the LTO sintered plate was used as the negative electrode layer.
  • Comparative Examples 1 and 2 Lithium ion batteries according to Comparative Examples 1 and 2 were produced in the same manner as in Example 1 except that no subcomponent was added to the solid electrolyte layer. However, in Comparative Example 1, the firing temperature was 500 ° C., and in Comparative Example 2, the firing temperature was 900 ° C.
  • the porosity was calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the pores in the solid electrolyte layer by the total area.
  • the solid electrolyte layer was densified by firing at a temperature equal to or higher than the melting point of the second solid electrolyte (oxide-based ceramic material) contained in the solid electrolyte layer.
  • the average porosity of the solid electrolyte layer could be 9% or less.
  • the average porosity of the solid electrolyte layer was 9%. I was able to:
  • Examples 1 to 11 and 19 in which an oxide-based ceramic material is used for the second solid electrolyte of the solid electrolyte examples 1 to 6, 9 to 11 and 19 in which the firing temperature is 600 ° C. or less, and a plastic material
  • Examples 12 to 18 and 20 in which was used for the second solid electrolyte of the solid electrolyte the battery internal resistance could be further reduced. This is because the formation of the solid electrolyte layer by a low-temperature process can suppress the formation of the high resistance layer by reacting the active material of the positive electrode layer or the negative electrode layer with the solid electrolyte.
  • Examples 12 to 18 and 20 in which a plastic material is used for the second solid electrolyte of the solid electrolyte layer examples 12 to 16 and 20 in which the average content of the second solid electrolyte is 4 wt% or more and 30 wt% or less. Then, the average porosity of the solid electrolyte layer could be reduced to 7% or less.
  • Example 19 in which the first and second intermediate layers constituted by the second solid electrolyte of the solid electrolyte layer were provided, the battery internal resistance could be further reduced as compared with Example 2. This is because the adhesion between the positive electrode layer and the solid electrolyte layer can be improved by the first intermediate layer, and the adhesion between the negative electrode layer and the solid electrolyte layer can be improved by the second intermediate layer.
  • Example 21 was performed in the same manner as in Example 1 except that a molded body of the positive electrode layer was produced by molding a mixture of the LCO powder, the main component of the solid electrolyte layer, and the subcomponent of the solid electrolyte layer by a tape molding method. , 22 were produced.
  • Example 21 Li 1.5 Al 0.5 Ge 1.5 using (PO 4) 3 (LAGP) in the main component of the solid electrolyte layer, Li 4 SiO 4 -Li 3 to subcomponent BO 3 was used.
  • the main component and subcomponent of the LCO powder and the solid electrolyte layer were mixed at a ratio of 50 wt%: 46 wt%: 4 wt%.
  • the LCO powder, the main component and the subcomponent of the solid electrolyte layer were mixed at a ratio of 70 wt%: 10 wt%: 20 wt%.
  • the positive electrode layer, the solid electrolyte layer, and the negative electrode layer were simultaneously formed by laminating and respectively firing the positive electrode layer, the solid electrolyte layer, and the negative electrode layer.
  • Example 23 to 27 Lithium ion batteries according to Examples 23 to 27 were fabricated by the same process as in Examples 21 and 22, except that an LTO sintered plate was used as the negative electrode layer.
  • the mixing ratio of the positive electrode active material and the solid electrolyte (main component and subcomponent) in the positive electrode layer was changed for each example.
  • Example 28 to 32 Lithium ion batteries according to Examples 28 to 32 were produced in the same manner as in Examples 21 and 22, except that an LCO sintered plate was used as the positive electrode layer.
  • the mixing ratio of the negative electrode active material and the solid electrolyte (main component and subcomponent) in the negative electrode layer was changed for each example.
  • Comparative Example 3 A comparative example was produced in the same manner as in Example 21 except that the molded body of the positive electrode layer was formed by mixing the main component and subcomponent of the LCO powder and the solid electrolyte layer in a ratio of 50 wt%: 48 wt%: 2 wt%. The lithium ion battery which concerns on 3 was produced.
  • Comparative Example 4 Comparative example according to the same steps as in Example 28 except that the molded body of the negative electrode layer was formed by mixing the main component and subcomponent of the LCO powder and the solid electrolyte layer in a ratio of 50 wt%: 48 wt%: 2 wt%. The lithium ion battery which concerns on 4 was produced.
  • the porosity was measured at four locations that divide the negative electrode layer into 5 equal parts in the thickness direction, and arithmetically averaged to obtain the negative electrode layers of Examples 21, 22, 28 to 32 The average porosity was obtained.
  • the porosity was calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the pores in the solid electrolyte layer by the total area.
  • the positive electrode layer could be densified by adding the main component and subcomponents of the solid electrolyte layer to the positive electrode active material, so that the porosity of the positive electrode layer could be suppressed to 9% or less.
  • Comparative Example 3 since the minor component of the solid electrolyte layer added to the positive electrode active material was small and the positive electrode layer could not be densified, the average porosity of the positive electrode layer was 10%. Therefore, in Examples 21 to 27, the battery internal resistance could be reduced as compared with Comparative Example 3.
  • the negative electrode layer was densified by adding the main component and subcomponents of the solid electrolyte layer to the negative electrode active material, so that the porosity of the negative electrode layer was suppressed to 9% or less. did it.
  • Comparative Example 4 since the minor component of the solid electrolyte layer added to the negative electrode active material was small and the negative electrode layer could not be densified, the average porosity of the negative electrode layer was 10%. Therefore, in Examples 21, 22, 28 to 32, the battery internal resistance could be reduced as compared with Comparative Example 4.
  • Example 21, 22, 28 to 32 in Examples 21, 22, 28, and 29 in which the average content of the second solid electrolyte was 4 wt% or more and 20 wt% or less, the porosity was suppressed to 6% or less. The battery internal resistance could be further reduced.

Abstract

A lithium-ion cell (100), provided with: a positive electrode layer (106); a negative electrode layer (108); and a solid electrolyte layer (107) disposed between the positive electrode layer (106) and the negative electrode layer (108). The solid electrolyte layer (107) contains a first solid electrolyte, which is a main component, and a second solid electrolyte, which is an auxiliary component. The average porosity of the solid electrolyte layer (107) is 9% or less.

Description

リチウムイオン電池及びその製造方法Lithium ion battery and manufacturing method thereof
　本発明は、リチウムイオン電池及びその製造方法に関する。 The present invention relates to a lithium ion battery and a method for manufacturing the same.
　近年、固体電解質を用いたリチウムイオン電池の研究開発が盛んである。リチウムイオン電池は、正極活物質を含む正極層と、負極活物質を含む負極層と、イオン伝導体を含む固体電解質層とを備える。 In recent years, research and development of lithium ion batteries using solid electrolytes has been active. The lithium ion battery includes a positive electrode layer including a positive electrode active material, a negative electrode layer including a negative electrode active material, and a solid electrolyte layer including an ion conductor.
　このようなリチウムイオン電池を焼結法で作製する場合、焼成温度が高いと、正極層中又は負極層中の活物質と固体電解質層中のイオン伝導体とが反応して高抵抗層が形成されるおそれがある。 When producing such a lithium ion battery by a sintering method, if the firing temperature is high, the active material in the positive electrode layer or the negative electrode layer reacts with the ion conductor in the solid electrolyte layer to form a high resistance layer. There is a risk of being.
　そこで、特許文献１では、焼成温度を７００℃まで低下させるために、粒径比が制御されたイオン伝導体と焼結助剤とを含む固体電解質層用材料を用いることが提案されている。特許文献１では、イオン伝導の主体であるイオン伝導体の含有率を多くしてイオン伝導度を向上させるために、イオン伝導体に対する焼結助剤の含有率が３．５ｗｔ％以下に抑えられている。 Therefore, in Patent Document 1, it is proposed to use a solid electrolyte layer material containing an ion conductor with a controlled particle size ratio and a sintering aid in order to lower the firing temperature to 700 ° C. In Patent Document 1, in order to improve the ionic conductivity by increasing the content of the ionic conductor that is the main body of ionic conduction, the content of the sintering aid relative to the ionic conductor is suppressed to 3.5 wt% or less. ing.
　また、特許文献２では、電極（正極層又は負極層）と固体電解質層との間におけるイオン伝導性を向上させるために、固体電解質層を構成する固体電解質を電極に含有させることが提案されている。 Moreover, in patent document 2, in order to improve the ionic conductivity between an electrode (a positive electrode layer or a negative electrode layer) and a solid electrolyte layer, it is proposed that the electrode contains a solid electrolyte constituting the solid electrolyte layer. Yes.
特開２０１５－１８６３４号公報JP 2015-18634 A 特開２００７－２５８１６５号公報JP 2007-258165 A
　しかしながら、特許文献１及び２のリチウムイオン電池では、期待されたほどリチウムイオン電池の内部抵抗を低減できなかった。 However, in the lithium ion batteries of Patent Documents 1 and 2, the internal resistance of the lithium ion battery could not be reduced as expected.
　本発明者等が鋭意検討した結果、特許文献１では固体電解質層におけるイオン伝導体の含有率を多くすることでイオン伝導度の向上を図っているが、イオン伝導度を向上させて内部抵抗を低減させるには、イオン伝導体の含有率を高めるよりも、固体電解質層の気孔率を低くしてイオン伝導可能な領域を広げた方が有利であるという新たな知見を得た。 As a result of intensive studies by the present inventors, Patent Document 1 attempts to improve the ionic conductivity by increasing the content of the ionic conductor in the solid electrolyte layer. However, by improving the ionic conductivity, the internal resistance is reduced. In order to reduce this, new knowledge was obtained that it is more advantageous to expand the ion-conducting region by lowering the porosity of the solid electrolyte layer, rather than increasing the content of the ionic conductor.
　同様に、本発明者等が鋭意検討した結果、特許文献２のように電極に固体電解質を含有させる場合には、電極の気孔率を低くすることによってリチウムイオン電池の内部抵抗を低減できるという新たな知見を得た。 Similarly, as a result of intensive studies by the present inventors, when the electrode contains a solid electrolyte as in Patent Document 2, the internal resistance of the lithium ion battery can be reduced by lowering the porosity of the electrode. I got a good knowledge.
　本発明は、上述の知見に基づいてなされたものであり、内部抵抗を低減可能なリチウムイオン電池及びその製造方法を提供することを目的とする。 The present invention has been made based on the above-described knowledge, and an object thereof is to provide a lithium ion battery capable of reducing internal resistance and a method for manufacturing the lithium ion battery.
　本発明に係るリチウムイオン電池は、正極層と、負極層と、正極層と負極層との間に配置される固体電解質層とを備える。固体電解質層は、主成分である第１固体電解質と、副成分である第２固体電解質とを含有する。固体電解質層の平均気孔率は、９％以下である。 The lithium ion battery according to the present invention includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer. The solid electrolyte layer contains a first solid electrolyte that is a main component and a second solid electrolyte that is a subcomponent. The average porosity of the solid electrolyte layer is 9% or less.
　本発明によれば、内部抵抗を低減可能なリチウムイオン電池及びその製造方法を提供することができる。 According to the present invention, it is possible to provide a lithium ion battery capable of reducing internal resistance and a manufacturing method thereof.
リチウムイオン電池の構成を模式的に示す断面図Sectional drawing which shows the structure of a lithium ion battery typically
　（リチウムイオン電池１００）
　図１は、リチウムイオン電池１００の構成を模式的に示す断面図である。板片状に構成されたチップ型のリチウムイオン電池１００は、充放電によって繰り返し使用可能な二次電池（充電式電池）である。 (Lithium ion battery 100)
FIG. 1 is a cross-sectional view schematically showing the configuration of the lithium ion battery 100. The chip-type lithium ion battery 100 configured in a plate shape is a secondary battery (rechargeable battery) that can be repeatedly used by charging and discharging.
　リチウムイオン電池１００は、正極側集電層１０１、負極側集電層１０２、外装材１０３，１０４、集電接続層１０５、正極層１０６、固体電解質層１０７及び負極層１０８を含む。 The lithium ion battery 100 includes a positive electrode side current collecting layer 101, a negative electrode side current collecting layer 102, exterior materials 103 and 104, a current collecting connection layer 105, a positive electrode layer 106, a solid electrolyte layer 107, and a negative electrode layer 108.
　正極側集電層１０１、集電接続層１０５、正極層１０６、固体電解質層１０７、負極層１０８及び負極側集電層１０２は、積層方向Ｘにおいて順次積層されている。正極側集電層１０１、集電接続層１０５及び正極層１０６によって正極部１１０が構成される。負極側集電層１０２及び負極層１０８によって負極部１２０が構成される。 The positive electrode side current collecting layer 101, the current collecting connection layer 105, the positive electrode layer 106, the solid electrolyte layer 107, the negative electrode layer 108, and the negative electrode side current collecting layer 102 are sequentially laminated in the laminating direction X. The positive electrode part 110 is constituted by the positive electrode side current collecting layer 101, the current collecting connection layer 105 and the positive electrode layer 106. The negative electrode side current collecting layer 102 and the negative electrode layer 108 constitute a negative electrode portion 120.
　１．正極側集電層１０１
　正極側集電層１０１は、正極層１０６の外側に配置される。正極側集電層１０１は、集電接続層１０５を介して正極層１０６と機械的かつ電気的に接続される。正極側集電層１０１は、正極集電体として機能する。 1. Positive electrode side current collecting layer 101
The positive electrode side current collecting layer 101 is disposed outside the positive electrode layer 106. The positive electrode side current collecting layer 101 is mechanically and electrically connected to the positive electrode layer 106 through the current collecting connection layer 105. The positive electrode side current collecting layer 101 functions as a positive electrode current collector.
　正極側集電層１０１は、金属によって構成することができる。正極側集電層１０１を構成する金属としては、ステンレス、アルミニウム、銅、白金、ニッケルなどが挙げられ、特にアルミニウム、ニッケル及びステンレスが好適である。正極側集電層１０１は、板状又は箔状に形成することができ、特に箔状が好ましい。従って、正極側集電層１０１としてアルミニウム箔、ニッケル箔、又は、ステンレス箔を用いることが特に好ましい。正極側集電層１０１が箔状に形成される場合、正極側集電層１０１の厚さは１μｍ以上３０μｍ以下とすることができ、５μｍ以上２５μｍ以下が好ましく、１０μｍ以上２０μｍ以下がより好ましい。 The positive electrode side current collecting layer 101 can be made of metal. Examples of the metal constituting the positive electrode side current collecting layer 101 include stainless steel, aluminum, copper, platinum, nickel and the like, and aluminum, nickel and stainless steel are particularly preferable. The positive current collecting layer 101 can be formed in a plate shape or a foil shape, and a foil shape is particularly preferable. Therefore, it is particularly preferable to use an aluminum foil, a nickel foil, or a stainless steel foil as the positive electrode side current collecting layer 101. When the positive electrode side current collecting layer 101 is formed in a foil shape, the thickness of the positive electrode side current collecting layer 101 can be 1 μm or more and 30 μm or less, preferably 5 μm or more and 25 μm or less, and more preferably 10 μm or more and 20 μm or less.
　２．負極側集電層１０２
　負極側集電層１０２は、負極層１０８の外側に配置される。負極側集電層１０２は、負極層１０８と機械的かつ電気的に接続される。負極側集電層１０２は、負極集電体として機能する。負極側集電層１０２は、金属によって構成することができる。負極側集電層１０２は、正極側集電層１０１と同様の材料によって構成することができる。従って、負極側集電層１０２としては、アルミニウム箔、ニッケル箔、又は、ステンレス箔を用いることが特に好ましい。負極側集電層１０２が箔状に形成される場合、負極側集電層１０２の厚さは１μｍ以上３０μｍ以下とすることができ、５μｍ以上２５μｍ以下が好ましく、１０μｍ以上２０μｍ以下がより好ましい。 2. Negative electrode side current collecting layer 102
The negative electrode side current collecting layer 102 is disposed outside the negative electrode layer 108. The negative electrode side current collecting layer 102 is mechanically and electrically connected to the negative electrode layer 108. The negative electrode side current collecting layer 102 functions as a negative electrode current collector. The negative electrode side current collection layer 102 can be comprised with a metal. The negative electrode side current collecting layer 102 can be made of the same material as that of the positive electrode side current collecting layer 101. Therefore, it is particularly preferable to use an aluminum foil, a nickel foil, or a stainless steel foil as the negative electrode side current collecting layer 102. When the negative electrode side current collecting layer 102 is formed in a foil shape, the thickness of the negative electrode side current collecting layer 102 can be 1 μm or more and 30 μm or less, preferably 5 μm or more and 25 μm or less, and more preferably 10 μm or more and 20 μm or less.
　３．外装材１０３，１０４
　外装材１０３，１０４は、正極側集電層１０１と負極側集電層１０２の隙間を封止する。外装材１０３，１０４は、正極層１０６、固体電解質層１０７及び負極層１０８によって構成される単電池の側方を取り囲む。外装材１０３，１０４は、リチウムイオン電池１００内への水分の侵入を抑制する。 3. Exterior material 103, 104
The exterior materials 103 and 104 seal a gap between the positive electrode side current collecting layer 101 and the negative electrode side current collecting layer 102. The packaging materials 103 and 104 surround the side of the unit cell constituted by the positive electrode layer 106, the solid electrolyte layer 107, and the negative electrode layer 108. The exterior materials 103 and 104 suppress moisture intrusion into the lithium ion battery 100.
　外装材１０３，１０４の抵抗率は、正極側集電層１０１と負極側集電層１０２の間の電気的絶縁性を確保するために１×１０６Ωｃｍ以上が好ましく、１×１０７Ωｃｍ以上がより好ましく、１×１０８Ωｃｍ以上がさらに好ましい。このような外装材１０３，１０４は、電気絶縁性の封着材によって構成することができる。封着材としては、樹脂を含む樹脂系封着材を用いることができる。樹脂系封着材を用いることによって、外装材１０３，１０４の形成を比較的低温（例えば４００℃以下）で行うことができるため、加熱によるリチウムイオン電池１００の破壊や変質を抑制できる。 The resistivity of the exterior materials 103 and 104 is preferably 1 × 10 6 Ωcm or more, and preferably 1 × 10 7 Ωcm or more in order to ensure electrical insulation between the positive electrode side current collection layer 101 and the negative electrode side current collection layer 102. Is more preferably 1 × 10 8 Ωcm or more. Such exterior material 103,104 can be comprised with an electrically insulating sealing material. As the sealing material, a resin-based sealing material containing a resin can be used. By using the resin-based sealing material, the exterior materials 103 and 104 can be formed at a relatively low temperature (for example, 400 ° C. or lower), so that the destruction and deterioration of the lithium ion battery 100 due to heating can be suppressed.
　外装材１０３，１０４は、樹脂フィルムの積層や液状樹脂のディスペンスなどによって形成することができる。 The exterior materials 103 and 104 can be formed by laminating resin films or dispensing liquid resin.
　４．集電接続層１０５
　集電接続層１０５は、正極層１０６と正極側集電層１０１との間に配置される。集電接続層１０５は、正極層１０６を正極側集電層１０１に機械的に接合するとともに、正極層１０６を正極側集電層１０１に電気的に接合する。 4). Current collecting connection layer 105
The current collecting connection layer 105 is disposed between the positive electrode layer 106 and the positive electrode side current collecting layer 101. The current collecting connection layer 105 mechanically bonds the positive electrode layer 106 to the positive electrode side current collecting layer 101 and electrically bonds the positive electrode layer 106 to the positive electrode side current collecting layer 101.
　集電接続層１０５は、導電性材料と接着剤を含む。導電性材料としては、導電性カーボンなどを用いることができる。接着剤としては、エポキシ系などの樹脂材料を用いることができる。集電接続層１０５の厚さは特に制限されないが、５μｍ以上１００μｍ以下とすることができ、１０μｍ以上５０μｍ以下であることが好ましい。 The current collecting connection layer 105 includes a conductive material and an adhesive. As the conductive material, conductive carbon or the like can be used. As the adhesive, an epoxy-based resin material can be used. The thickness of the current collector connection layer 105 is not particularly limited, but can be 5 μm or more and 100 μm or less, and preferably 10 μm or more and 50 μm or less.
　ただし、集電接続層１０５は、接着剤を含んでいなくてもよい。この場合、正極層１０６の裏面に集電接続層１０５（例えば金やアルミニウム）を直接成膜することで、集電接続層１０５と正極層１０６との電気的な接続を得ることができる。 However, the current collecting connection layer 105 may not contain an adhesive. In this case, an electrical connection between the current collector connection layer 105 and the positive electrode layer 106 can be obtained by directly forming the current collector connection layer 105 (eg, gold or aluminum) on the back surface of the positive electrode layer 106.
　５．正極層１０６
　正極層１０６は、板状に成形される。正極層１０６は、固体電解質側表面１０６ａと集電接続層側表面１０６ｂとを有する。正極層１０６は、固体電解質側表面１０６ａにおいて固体電解質層１０７に接続される。正極層１０６は、集電接続層側表面１０６ｂにおいて集電接続層１０５に接続される。固体電解質側表面１０６ａと集電接続層側表面１０６ｂそれぞれは、正極層１０６の「板面」である。固体電解質側表面１０６ａは、正極層１０６の断面を走査型電子顕微鏡（ＳＥＭ：Ｓｃａｎｎｉｎｇ　Ｅｌｅｃｔｒｏｎ　Ｍｉｃｒｏｓｃｏｐｅ)によって観察した場合に、正極層１０６と固体電解質層１０７との界面を最小二乗法によって直線近似した線によって規定される。集電接続層側表面１０６ｂは、正極層１０６の断面をＳＥＭによって観察した場合に、正極層１０６と集電接続層１０５との界面を最小二乗法によって直線近似した線によって規定される。 5). Positive electrode layer 106
The positive electrode layer 106 is formed into a plate shape. The positive electrode layer 106 has a solid electrolyte side surface 106a and a current collecting connection layer side surface 106b. The positive electrode layer 106 is connected to the solid electrolyte layer 107 on the solid electrolyte side surface 106a. The positive electrode layer 106 is connected to the current collector connection layer 105 on the current collector connection layer side surface 106b. Each of the solid electrolyte side surface 106 a and the current collecting connection layer side surface 106 b is a “plate surface” of the positive electrode layer 106. The solid electrolyte side surface 106a is a line obtained by linearly approximating the interface between the positive electrode layer 106 and the solid electrolyte layer 107 by the least square method when a cross section of the positive electrode layer 106 is observed with a scanning electron microscope (SEM). It is prescribed by. The current collecting connection layer side surface 106b is defined by a line obtained by linear approximation of the interface between the positive electrode layer 106 and the current collecting connection layer 105 by the least square method when the cross section of the positive electrode layer 106 is observed by SEM.
　正極層１０６の厚みは特に制限されないが、２０μｍ以上が好ましく、２５μｍ以上がより好ましく、３０μｍ以上がさらに好ましい。特に、正極層１０６の厚みを５０μｍ以上にすることによって、単位面積当りの活物質容量を十分に確保してリチウムイオン電池１００のエネルギー密度を高めることができる。また、正極層１０６の厚みの上限値は特に制限されないが、充放電の繰り返しに伴う電池特性の劣化（特に、抵抗値の上昇）の抑制を考慮すると、２００μｍ未満が好ましく、１５０μｍ以下がより好ましく、１２０μｍ以下がさらに好ましく、１００μｍ以下が特に好ましい。 The thickness of the positive electrode layer 106 is not particularly limited, but is preferably 20 μm or more, more preferably 25 μm or more, and further preferably 30 μm or more. In particular, by setting the thickness of the positive electrode layer 106 to 50 μm or more, the active material capacity per unit area can be sufficiently secured and the energy density of the lithium ion battery 100 can be increased. The upper limit value of the thickness of the positive electrode layer 106 is not particularly limited, but is preferably less than 200 μm and more preferably 150 μm or less in consideration of suppression of deterioration of battery characteristics (particularly increase in resistance value) due to repeated charge / discharge. 120 μm or less is more preferable, and 100 μm or less is particularly preferable.
　正極層１０６の板面に平行な方向（以下、「板面方向」という。）における膨張収縮率は、０．７％以下に抑えられていることが好ましい。このように、正極層１０６の膨張収縮率が十分に低ければ、リチウムイオン電池１００のレート特性の向上を目的として正極層１０６の厚みを３０μｍ以下にしたとしても、固体電解質層１０７の欠陥又は／及び正極層１０６の剥離を抑制することができる。従って、正極層１０６の厚みは、リチウムイオン電池１００の放電容量と正極層１０６の膨張収縮率を考慮して適宜設定することができる。 The expansion / contraction rate in a direction parallel to the plate surface of the positive electrode layer 106 (hereinafter referred to as “plate surface direction”) is preferably suppressed to 0.7% or less. In this way, if the positive electrode layer 106 has a sufficiently low expansion / contraction rate, even if the thickness of the positive electrode layer 106 is set to 30 μm or less for the purpose of improving the rate characteristics of the lithium ion battery 100, defects in the solid electrolyte layer 107 or / In addition, peeling of the positive electrode layer 106 can be suppressed. Therefore, the thickness of the positive electrode layer 106 can be appropriately set in consideration of the discharge capacity of the lithium ion battery 100 and the expansion / contraction rate of the positive electrode layer 106.
　正極層１０６は、複数の正極活物質結晶粒（一次粒子）が結合することによって構成された焼結板であることが好ましい。これにより、気相法によって形成される膜に比べて厚みを大きくできるため、リチウムイオン電池１００の容量及びエネルギー密度を向上させることができる。また、正極層１０６の組成を原料の秤量によって調整できるため、気相法によって形成される膜に比べて高精度に組成を制御できる。 The positive electrode layer 106 is preferably a sintered plate configured by combining a plurality of positive electrode active material crystal grains (primary particles). Thereby, since the thickness can be increased as compared with the film formed by the vapor phase method, the capacity and energy density of the lithium ion battery 100 can be improved. In addition, since the composition of the positive electrode layer 106 can be adjusted by weighing the raw materials, the composition can be controlled with higher accuracy than a film formed by a vapor phase method.
　正極活物質結晶粒は、主に板状に形成されるが、直方体状、立方体状及び球状などに形成されたものが含まれていてもよい。正極活物質結晶粒は、リチウム複合酸化物によって構成される。リチウム複合酸化物とは、ＬｉｘＭＯ２（０．０５＜ｘ＜１．１０であり、Ｍは少なくとも１種類の遷移金属であり、Ｍは典型的にＣｏ，Ｎｉ，Ｍｎのうちの１種以上を含む。）で表される酸化物である。リチウム複合酸化物は、層状岩塩構造を有する。層状岩塩構造とは、リチウム層とリチウム以外の遷移金属層とが酸素の層を挟んで交互に積層された結晶構造、すなわち、酸化物イオンを介して遷移金属イオン層とリチウム単独層とが交互に積層した結晶構造（典型的には、α－ＮａＦｅＯ２型構造、すなわち立方晶岩塩型構造の［１１１］軸方向に遷移金属とリチウムとが規則配列した構造）をいう。 The positive electrode active material crystal grains are mainly formed in a plate shape, but may include those formed in a rectangular parallelepiped shape, a cubic shape, a spherical shape, or the like. The positive electrode active material crystal grains are composed of a lithium composite oxide. The lithium composite oxide is Li x MO 2 (0.05 <x <1.10, M is at least one transition metal, and M is typically one of Co, Ni, and Mn. Including the above.) The lithium composite oxide has a layered rock salt structure. The layered rock salt structure is a crystal structure in which lithium layers and transition metal layers other than lithium are alternately stacked with oxygen layers in between, that is, the transition metal ion layers and lithium single layers are alternately arranged via oxide ions. (Typically an α-NaFeO 2 type structure, ie, a structure in which transition metals and lithium are regularly arranged in the [111] axis direction of a cubic rock salt type structure).
　リチウム複合酸化物としては、例えば、ＬｉｘＣｏＯ２（コバルト酸リチウム）、ＬｉｘＮｉＯ２（ニッケル酸リチウム）、ＬｉｘＭｎＯ２（マンガン酸リチウム）、ＬｉｘＮｉＭｎＯ２（ニッケル・マンガン酸リチウム）、ＬｉｘＮｉＣｏＯ２（ニッケル・コバルト酸リチウム）、ＬｉｘＣｏＮｉＭｎＯ２（コバルト・ニッケル・マンガン酸リチウム）、ＬｉｘＣｏＭｎＯ２（コバルト・マンガン酸リチウム）などが挙げられ、ＬｉｘＣｏＯ２が特に好ましい。 Examples of the lithium composite oxide include Li x CoO 2 (lithium cobaltate), Li x NiO 2 (lithium nickelate), Li x MnO 2 (lithium manganate), and Li x NiMnO 2 (nickel / lithium manganate). Li x NiCoO 2 (nickel / lithium cobaltate), Li x CoNiMnO 2 (cobalt / nickel / lithium manganate), Li x CoMnO 2 (cobalt / lithium manganate), etc., and Li x CoO 2 is particularly preferable. .
　なお、リチウム複合酸化物には、Ｍｇ，Ａｌ，Ｓｉ，Ｃａ，Ｔｉ，Ｖ，Ｃｒ，Ｆｅ，Ｃｕ，Ｚｎ，Ｇａ，Ｇｅ，Ｓｒ，Ｙ，Ｚｒ，Ｎｂ，Ｍｏ，Ａｇ，Ｓｎ，Ｓｂ，Ｔｅ，Ｂａ，Ｂｉ、Ｗなどのうち一種以上の元素が含まれていてもよい。 The lithium composite oxide includes Mg, Al, Si, Ca, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ag, Sn, Sb, Te. , Ba, Bi, W, etc. may contain one or more elements.
　正極活物質結晶粒は、リチウムイオンの伝導方向に配向されていることが好ましい。具体的には、正極活物質結晶粒の（００３）面が、積層方向Ｘに配向されていることが好ましい。これによって、リチウムイオンの蓄積時及び放出時における抵抗を低減できるため、高入力時（すなわち、充電時）に多くのリチウムイオンを放出できるとともに、高出力時（すなわち、放電時）に多くのリチウムイオンを蓄積することができる。 The positive electrode active material crystal grains are preferably oriented in the lithium ion conduction direction. Specifically, the (003) plane of the positive electrode active material crystal grains is preferably oriented in the stacking direction X. As a result, the resistance at the time of accumulation and release of lithium ions can be reduced, so that a large amount of lithium ions can be released at the time of high input (that is, during charging) and a large amount of lithium ions at the time of high output (that is, during discharge). Ions can be accumulated.
　６．固体電解質層１０７
　固体電解質層１０７は、主成分である第１固体電解質と、副成分である第２固体電解質とを含有する。固体電解質層１０７において、第１固体電解質は母材であり、第２固体電解質は添加材であるといってもよい。 6). Solid electrolyte layer 107
The solid electrolyte layer 107 contains a first solid electrolyte that is a main component and a second solid electrolyte that is a subcomponent. In the solid electrolyte layer 107, the first solid electrolyte may be a base material, and the second solid electrolyte may be an additive.
　（１）第１固体電解質
　第１固体電解質は、リチウムイオン伝導性を有する酸化物系セラミックス材料である。第１固体電解質としての酸化物系セラミックス材料には、ガーネット系セラミックス材料、窒化物系セラミックス材料、ペロブスカイト系セラミックス材料、リン酸系セラミックス材料、及びゼオライト系材料の群から選択される少なくとも一種を用いることができる。 (1) First solid electrolyte The first solid electrolyte is an oxide ceramic material having lithium ion conductivity. The oxide ceramic material as the first solid electrolyte is at least one selected from the group consisting of garnet ceramic materials, nitride ceramic materials, perovskite ceramic materials, phosphate ceramic materials, and zeolite materials. be able to.
　ガーネット系セラミックス材料としては、Ｌｉ－Ｌａ－Ｚｒ－Ｏ材料（具体的には、Ｌｉ７Ｌａ３Ｚｒ２Ｏ１２など）及びＬｉ－Ｌａ－Ｔａ－Ｏ材料（具体的には、Ｌｉ７Ｌａ３Ｔａ２Ｏ１２など）が挙げられる。 Examples of garnet-based ceramic materials include Li—La—Zr—O materials (specifically, Li 7 La 3 Zr 2 O 12 and the like) and Li—La—Ta—O materials (specifically, Li 7 La 3 Ta 2 O 12 etc.).
　窒化物系セラミックス材料の例としては、Ｌｉ３Ｎ、ＬｉＰＯＮ（具体的には、ＬｉｘＰＯｙＮｚ（２≦ｘ≦４、３≦ｙ≦５、０．１≦ｚ≦０．９））などが挙げられる。 Examples of nitride-based ceramic materials include Li 3 N and LiPON (specifically, Li x PO y N z (2 ≦ x ≦ 4, 3 ≦ y ≦ 5, 0.1 ≦ z ≦ 0.9)) ) And the like.
　ペロブスカイト系セラミックス材料の例としては、Ｌｉ－Ｌａ－Ｔｉ－Ｏ材料（具体的には、ＬｉＬａ１－ｘＴｉｘＯ３（０．０４≦ｘ≦０．１４））などが挙げられる。 Examples of perovskite ceramic materials include Li—La—Ti—O materials (specifically, LiLa 1-x Ti x O 3 (0.04 ≦ x ≦ 0.14)).
　リン酸系セラミックス材料の例としては、Ｌｉ－Ａｌ－Ｔｉ－Ｐ－Ｏ材料（具体的には、Ｌｉ（Ａｌ，Ｔｉ）２（ＰＯ４）３），Ｌｉ－Ａｌ－Ｇｅ－Ｐ－Ｏ材料（具体的には、Ｌｉ１．５Ａｌ０．５Ｇｅ１．５（ＰＯ４）３など）、及びＬｉ－Ａｌ－Ｔｉ－Ｓｉ－Ｐ－Ｏ材料（具体的には、Ｌｉ１+ｘ+ｙＡｌｘＴｉ２－ｘＳｉｙＰ３―ｙＯ１２（０≦ｘ≦０．４、０＜ｙ≦０．６）など）が挙げられる。 Examples of phosphoric acid-based ceramic materials include Li—Al—Ti—P—O materials (specifically, Li (Al, Ti) 2 (PO 4 ) 3 ), Li—Al—Ge—PO materials. (Specifically, Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 etc.), and Li—Al—Ti—Si—P—O materials (specifically, Li 1 + x + y Al x Ti 2-x Si y P 3-y O 12 (0 ≦ x ≦ 0.4,0 <y ≦ 0.6) , and the like).
　固体電解質層１０７における第１固体電解質の平均含有率は、７０ｗｔ％以上９６ｗｔ％以下とすることができる。第１固体電解質の平均含有率は、固体電解質層１０７の断面において、厚み方向（積層方向Ｘと同じ）に固体電解質層１０７を５等分する４箇所で第１固体電解質の含有率を測定し、それを算術平均することによって得られる。各箇所における第１固体電解質の含有率は、エネルギー分散型Ｘ線分光分析装置（ＥＤＳ）を用いた元素分析によって測定される。 The average content of the first solid electrolyte in the solid electrolyte layer 107 can be 70 wt% or more and 96 wt% or less. The average content of the first solid electrolyte is determined by measuring the content of the first solid electrolyte at four locations in the cross section of the solid electrolyte layer 107 that equally divide the solid electrolyte layer 107 into five in the thickness direction (same as the stacking direction X). Is obtained by arithmetically averaging it. The content rate of the first solid electrolyte in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
　（２）第２固体電解質
　第２固体電解質は、酸化物系セラミックス材料、可塑性材料、又はこれらの組み合わせである。第２固体電解質は、リチウムイオン伝導性を有していてもよいし、リチウムイオン伝導性を有していなくてもよい。第２固体電解質がリチウムイオン伝導性を有する場合、第２固体電解質のリチウムイオン伝導度は、第１固体電解質のリチウムイオン伝導度より低くてもよい。 (2) Second solid electrolyte The second solid electrolyte is an oxide-based ceramic material, a plastic material, or a combination thereof. The second solid electrolyte may have lithium ion conductivity or may not have lithium ion conductivity. When the second solid electrolyte has lithium ion conductivity, the lithium ion conductivity of the second solid electrolyte may be lower than the lithium ion conductivity of the first solid electrolyte.
　ａ．酸化物系セラミックス材料
　第２固体電解質としての酸化物系セラミックス材料には、一般式ＬｉｘＡＯｙ（ただし、Ａは、Ｂ、Ｃ、Ｃｌ、Ａｌ、Ｓｉ、Ｐ、Ｓ、Ｔｉ、Ｚｒ、Ｎｂ、Ｍｏ、Ｔａ、又は、Ｗであり、ｘ及びｙは正の整数である。）で表されるものを用いることができる。具体的には、Ｌｉ３ＢＯ３、ＬｉＢＯ２、Ｌｉ２ＣＯ３、ＬｉＡｌＯ２、Ｌｉ４ＳｉＯ４、Ｌｉ２ＳｉＯ３、Ｌｉ３ＣｌＯ、ＬｉＰＯ３、Ｌｉ３ＰＯ４、Ｌｉ２ＳＯ４、Ｌｉ２ＴｉＯ３、Ｌｉ４Ｔｉ５Ｏ１２、Ｌｉ２Ｔｉ２Ｏ５、Ｌｉ２ＺｒＯ３、ＬｉＮｂＯ３、Ｌｉ２ＭｏＯ４、Ｌｉ２ＷＯ４の群から選択される少なくとも一種が挙げられる。 a. Oxide-based ceramic material The oxide-based ceramic material as the second solid electrolyte includes a general formula Li x AO y (where A is B, C, Cl, Al, Si, P, S, Ti, Zr, Nb) , Mo, Ta, or W, and x and y are positive integers). Specifically, Li 3 BO 3 , LiBO 2 , Li 2 CO 3 , LiAlO 2 , Li 4 SiO 4 , Li 2 SiO 3 , Li 3 ClO, LiPO 3 , Li 3 PO 4 , Li 2 SO 4 , Li 2 Examples include at least one selected from the group consisting of TiO 3 , Li 4 Ti 5 O 12 , Li 2 Ti 2 O 5 , Li 2 ZrO 3 , LiNbO 3 , Li 2 MoO 4 , and Li 2 WO 4 .
　第２固体電解質として酸化物系セラミックス材料を用いる場合、焼結法によって固体電解質層１０７を作製することができる。この場合、第２固体電解質は、第１固体電解質の液相焼結を促進させる焼結助剤として機能する。第２固体電解質である酸化物系セラミックス材料の融点は、６００℃以下であることが好ましい。これによって、比較的低温で焼成できるため、正極層１０６中又は負極層１０８中の活物質と第１又は第２固体電解質とが反応して高抵抗層が形成されてしまうことを抑制できる。その結果、リチウムイオン電池１００の容量低下を抑えることができる。 When an oxide ceramic material is used as the second solid electrolyte, the solid electrolyte layer 107 can be produced by a sintering method. In this case, the second solid electrolyte functions as a sintering aid that promotes liquid phase sintering of the first solid electrolyte. The melting point of the oxide-based ceramic material that is the second solid electrolyte is preferably 600 ° C. or lower. Thereby, since it can be fired at a relatively low temperature, it can be suppressed that the active material in the positive electrode layer 106 or the negative electrode layer 108 reacts with the first or second solid electrolyte to form a high resistance layer. As a result, a decrease in capacity of the lithium ion battery 100 can be suppressed.
　第２固体電解質として酸化物系セラミックス材料を用いる場合、固体電解質層１０７における第２固体電解質の平均含有率は、４ｗｔ％以上が好ましく、１０ｗｔ％以上がより好ましく、１５ｗｔ％以上が特に好ましい。これによって、液相焼結した第１固体電解質の隙間に第２固体電解質を十分に充填させることができるため、後述するように、固体電解質層１０７を緻密化することができる。 When using an oxide-based ceramic material as the second solid electrolyte, the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 4 wt% or more, more preferably 10 wt% or more, and particularly preferably 15 wt% or more. Accordingly, the second solid electrolyte can be sufficiently filled in the gap between the liquid-phase sintered first solid electrolyte, so that the solid electrolyte layer 107 can be densified as described later.
　また、第２固体電解質として酸化物系セラミックス材料を用いる場合、固体電解質層１０７における第２固体電解質の平均含有率は、３０ｗｔ％以下が好ましく、２５ｗｔ％以下がより好ましく、２０ｗｔ％以下が特に好ましい。これによって、第２固体電解質のリチウムイオン伝導度が低い場合であっても、固体電解質層１０７全体としてのリチウムイオン伝導度を維持することができる。 When an oxide ceramic material is used as the second solid electrolyte, the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 30 wt% or less, more preferably 25 wt% or less, and particularly preferably 20 wt% or less. . Thereby, even if the lithium ion conductivity of the second solid electrolyte is low, the lithium ion conductivity of the solid electrolyte layer 107 as a whole can be maintained.
　固体電解質層１０７における第２固体電解質としての酸化物系セラミックス材料の平均含有率は、固体電解質層１０７の断面において、厚み方向に固体電解質層１０７を５等分する４箇所で酸化物系セラミックス材料の含有率を測定し、それを算術平均することによって得られる。各箇所における酸化物系セラミックス材料の含有率は、エネルギー分散型Ｘ線分光分析装置（ＥＤＳ）を用いた元素分析によって測定される。 The average content of the oxide-based ceramic material as the second solid electrolyte in the solid electrolyte layer 107 is the oxide-based ceramic material at four locations where the solid electrolyte layer 107 is equally divided into five in the thickness direction in the cross section of the solid electrolyte layer 107. It is obtained by measuring the content of and averaging it. The content of the oxide-based ceramic material at each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
　ｂ．可塑性材料
　第２固体電解質としての可塑性材料には、ガラス材料、六フッ化アルミニウムリチウム（Ｌｉ３ＡｌＦ６）、ＮａＩ－ＬｉＢＨ４などを用いることができる。 b. Plastic material As the plastic material as the second solid electrolyte, glass material, lithium aluminum hexafluoride (Li 3 AlF 6 ), NaI—LiBH 4 or the like can be used.
　ガラス材料としては、Ｂｉ２Ｏ３、Ｂ２Ｏ３、又はこれらの混合物を用いることができる。第２固体電解質としてガラス材料を用いる場合、第１固体電解質と第２固体電解質との混合物を第２固体電解質の軟化点以上に加熱することによって、固体電解質層１０７を作製することができる。この場合、第２固体電解質であるガラス材料は、塑性変形することによって第１固体電解質の隙間に広がる。第２固体電解質の軟化点は、６００℃以下であることが好ましい。これによって、正極層１０６中又は負極層１０８中の活物質と第１又は第２固体電解質とが反応して高抵抗層が形成されることを抑制できる。 As the glass material, Bi 2 O 3 , B 2 O 3 , or a mixture thereof can be used. When a glass material is used as the second solid electrolyte, the solid electrolyte layer 107 can be produced by heating a mixture of the first solid electrolyte and the second solid electrolyte to a temperature above the softening point of the second solid electrolyte. In this case, the glass material that is the second solid electrolyte spreads in the gaps of the first solid electrolyte by plastic deformation. The softening point of the second solid electrolyte is preferably 600 ° C. or lower. Thereby, it is possible to prevent the active material in the positive electrode layer 106 or the negative electrode layer 108 from reacting with the first or second solid electrolyte to form a high resistance layer.
　第２固体電解質としてＬｉ３ＡｌＦ６及び／又はＮａＩ－ＬｉＢＨ４を用いる場合には、電気泳動堆積（ＥＰＤ：Ｅｌｅｃｔｒｏｐｈｏｒｅｔｉｃ　Ｄｅｐｏｓｉｔｉｏｎ）法を用いて第１固体電解質と第２固体電解質との混合物を堆積させた後に加圧することによって、固体電解質層１０７を作製することができる。この場合、第２固体電解質であるＬｉ３ＡｌＦ６及びＮａＩ－ＬｉＢＨ４は、塑性変形することによって第１固体電解質の隙間に広がる。Ｌｉ３ＡｌＦ６及びＮａＩ－ＬｉＢＨ４は、２０℃以上で可塑性を有するため、加熱することなく固体電解質層１０７を作製することができる。そのため、正極層１０６中又は負極層１０８中の活物質と第１又は第２固体電解質とが反応して高抵抗層が形成されることを抑制できる。 When Li 3 AlF 6 and / or NaI-LiBH 4 is used as the second solid electrolyte, a mixture of the first solid electrolyte and the second solid electrolyte is deposited using an electrophoretic deposition (EPD) method. After that, the solid electrolyte layer 107 can be produced by applying pressure. In this case, Li 3 AlF 6 and NaI—LiBH 4 that are the second solid electrolytes spread in the gaps of the first solid electrolyte by plastic deformation. Since Li 3 AlF 6 and NaI—LiBH 4 have plasticity at 20 ° C. or higher, the solid electrolyte layer 107 can be formed without heating. Therefore, it can suppress that the active material in the positive electrode layer 106 or the negative electrode layer 108 and the 1st or 2nd solid electrolyte react, and a high resistance layer is formed.
　また、第２固体電解質が潮解性を有する場合には、第１固体電解質と第２固体電解質との混合物を加圧する際の雰囲気湿度を高めることが有効である。これによって、正極層１０６と固体電解質層１０７との間に良好な界面を形成することができる。 Also, when the second solid electrolyte has deliquescence, it is effective to increase the atmospheric humidity when the mixture of the first solid electrolyte and the second solid electrolyte is pressurized. As a result, a good interface can be formed between the positive electrode layer 106 and the solid electrolyte layer 107.
　第２固体電解質として可塑性材料を用いる場合、固体電解質層１０７における第２固体電解質の平均含有率は、４ｗｔ％以上が好ましく、１０ｗｔ％以上がより好ましく、１５ｗｔ％以上が特に好ましい。これによって、第１固体電解質の隙間に第２固体電解質を十分に充填させることができるため、固体電解質層１０７を緻密化することができる。 When a plastic material is used as the second solid electrolyte, the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 4 wt% or more, more preferably 10 wt% or more, and particularly preferably 15 wt% or more. Thereby, the gap between the first solid electrolytes can be sufficiently filled with the second solid electrolyte, so that the solid electrolyte layer 107 can be densified.
　また、第２固体電解質として可塑性材料を用いる場合、固体電解質層１０７における第２固体電解質の平均含有率は、３０ｗｔ％以下が好ましく、２５ｗｔ％以下がより好ましく、２０ｗｔ％以下が特に好ましい。これによって、第２固体電解質である可塑性材料がリチウムイオン伝導性を有さない場合であっても、固体電解質層１０７全体としてのリチウムイオン伝導性が低下することを抑制できる。 Further, when a plastic material is used as the second solid electrolyte, the average content of the second solid electrolyte in the solid electrolyte layer 107 is preferably 30 wt% or less, more preferably 25 wt% or less, and particularly preferably 20 wt% or less. Thereby, even if the plastic material that is the second solid electrolyte does not have lithium ion conductivity, it is possible to suppress a decrease in lithium ion conductivity as the solid electrolyte layer 107 as a whole.
　固体電解質層１０７における可塑性材料の平均含有率は、固体電解質層１０７の断面において、厚み方向に固体電解質層１０７を５等分する４箇所で可塑性材料の含有率を測定し、それを算術平均することによって得られる。各箇所における可塑性材料の含有率は、エネルギー分散型Ｘ線分光分析装置（ＥＤＳ）を用いた元素分析によって測定される。 The average content of the plastic material in the solid electrolyte layer 107 is obtained by measuring the content of the plastic material at four locations where the solid electrolyte layer 107 is equally divided into five in the thickness direction in the cross section of the solid electrolyte layer 107, and arithmetically averaging them. Can be obtained. The content rate of the plastic material in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
　（３）固体電解質層１０７の構成
　固体電解質層１０７の平均気孔率は、９％以下である。すなわち、固体電解質層１０７の平均緻密度は、９１％以上である。このように、固体電解質層１０７の平均気孔率を十分低くしてイオン伝導可能な領域を広げることによって、イオン伝導体の含有率を高める以上に、固体電解質層１０７のイオン伝導度を向上させることができるため、リチウムイオン電池１００の内部抵抗を低減させることができる。固体電解質層１０７の平均気孔率は、７％以下が好ましく、５％以下が特に好ましい。 (3) Configuration of Solid Electrolyte Layer 107 The average porosity of the solid electrolyte layer 107 is 9% or less. That is, the average density of the solid electrolyte layer 107 is 91% or more. In this way, the ionic conductivity of the solid electrolyte layer 107 can be improved more than increasing the content of the ionic conductor by widening the ion conductive region by sufficiently reducing the average porosity of the solid electrolyte layer 107. Therefore, the internal resistance of the lithium ion battery 100 can be reduced. The average porosity of the solid electrolyte layer 107 is preferably 7% or less, and particularly preferably 5% or less.
　固体電解質層１０７の平均気孔率は、固体電解質層１０７の断面において、厚み方向に固体電解質層１０７を５等分する４箇所で気孔率を測定し、それを算術平均することによって得られる。気孔率は、各測定箇所において２００００倍率のＳＥＭ（電子顕微鏡）画像を取得し、固体電解質層１０７内における気孔の合計面積を固体電解質層１０７全体の面積で除することによって算出される。 The average porosity of the solid electrolyte layer 107 is obtained by measuring the porosity at four locations in the cross section of the solid electrolyte layer 107 that equally divide the solid electrolyte layer 107 into five in the thickness direction, and arithmetically averaging them. The porosity is calculated by obtaining an SEM (electron microscope) image at 20000 magnification at each measurement location, and dividing the total area of the pores in the solid electrolyte layer 107 by the area of the entire solid electrolyte layer 107.
　固体電解質層１０７は、実質的に硫黄を含有しないことが好ましい。実質的に硫黄を含有しないとは、固体電解質層１０７における硫黄の平均含有率が０．１ｗｔ％以下であることを意味する。これによって、リチウムイオン電池１００の外部から水分が侵入した場合に、固体電解質層１０７から有毒ガスが発生することを抑制できる。 It is preferable that the solid electrolyte layer 107 does not substantially contain sulfur. The phrase “substantially containing no sulfur” means that the average content of sulfur in the solid electrolyte layer 107 is 0.1 wt% or less. Accordingly, it is possible to suppress generation of toxic gas from the solid electrolyte layer 107 when moisture enters from the outside of the lithium ion battery 100.
　固体電解質層１０７における硫黄の平均含有率は、０．０１ｗｔ％以下がより好ましく、０．００１ｗｔ％以下が特に好ましい。固体電解質層１０７における硫黄の平均含有率は、固体電解質層１０７の断面において、厚み方向に固体電解質層１０７を５等分する４箇所で硫黄の含有率を測定し、それを算術平均することによって得られる。各箇所における硫黄の含有率は、エネルギー分散型Ｘ線分光分析装置（ＥＤＳ）を用いた元素分析によって測定される。 The average content of sulfur in the solid electrolyte layer 107 is more preferably 0.01 wt% or less, and particularly preferably 0.001 wt% or less. The average content of sulfur in the solid electrolyte layer 107 is obtained by measuring the sulfur content at four locations that divide the solid electrolyte layer 107 into 5 parts in the thickness direction in the cross section of the solid electrolyte layer 107 and arithmetically averaging them. can get. The sulfur content in each location is measured by elemental analysis using an energy dispersive X-ray spectrometer (EDS).
　固体電解質層１０７の厚さは、リチウムイオン伝導性の向上という観点からは薄いことが好ましいが、充放電時の信頼性（欠陥及びクラックの抑制、セパレータとしての機能など）を考慮して適宜設定することができる。固体電解質層１０７の厚さは、例えば１μｍ以上１０００μｍ以下とすることができる。固体電解質層１０７の厚さは、１０μｍ以上５００μｍ以下が好ましく、２０μｍ以上２００μｍ以下が特に好ましい。 The thickness of the solid electrolyte layer 107 is preferably thin from the viewpoint of improving lithium ion conductivity, but is set as appropriate in consideration of reliability during charge / discharge (suppression of defects and cracks, function as a separator, etc.). can do. The thickness of the solid electrolyte layer 107 can be, for example, 1 μm or more and 1000 μm or less. The thickness of the solid electrolyte layer 107 is preferably 10 μm or more and 500 μm or less, and particularly preferably 20 μm or more and 200 μm or less.
　７．負極層１０８
　負極層１０８は、固体電解質層１０７上に配置される。負極層１０８は、負極活物質を含有する。負極活物質は、リチウムイオンを吸蔵及び放出できるものであればよい。負極活物質としては、例えば、炭素質材料やリチウム吸蔵物質などを用いることができる。 7). Negative electrode layer 108
The negative electrode layer 108 is disposed on the solid electrolyte layer 107. The negative electrode layer 108 contains a negative electrode active material. The negative electrode active material may be any material that can occlude and release lithium ions. As the negative electrode active material, for example, a carbonaceous material or a lithium storage material can be used.
　炭素質材料としては、黒鉛、熱分解炭素類、コークス類、ガラス状炭素類、有機高分子化合物の焼成体、メソカーボンマイクロビーズ、炭素繊維、及び活性炭などが挙げられる。なお、黒鉛の一部は、リチウムと合金化し得る金属や酸化物などと置き換えられてもいよい。負極活物質として炭素質材料を用いる場合、負極層１０８の厚みは、１０μｍ以上５００μｍ以下とすることができる。 Examples of the carbonaceous material include graphite, pyrolytic carbons, cokes, glassy carbons, fired bodies of organic polymer compounds, mesocarbon microbeads, carbon fibers, and activated carbon. A part of graphite may be replaced with a metal or an oxide that can be alloyed with lithium. When a carbonaceous material is used as the negative electrode active material, the thickness of the negative electrode layer 108 can be 10 μm or more and 500 μm or less.
　リチウム吸蔵物質としては、金属リチウム、金属リチウムと他の元素（ケイ素、スズ、インジウム等）とを含む合金、リチウムに近い低電位で充放電できるケイ素又はスズ等の酸化物、Ｌｉ４Ｔｉ５Ｏ１２（ＬＴＯ）のようなリチウムとチタンとの酸化物、Ｌｉ２.６Ｃｏ０.４Ｎのようなリチウムとコバルトとの窒化物、及びＴｉＯ２（チタニア）などが挙げられる。リチウム吸蔵物質としてＬＴＯ又はＴｉＯ２を用いる場合、負極層１０８は、複数の負極活物質結晶粒（一次粒子）が結合することによって構成される焼結板であってもよい。なお、リチウム吸蔵物質の組成式は、リチウムイオンの吸蔵及び放出に応じて変わることは当然である。負極活物質としてリチウム吸蔵物質を用いる場合、負極層１０８の厚みは、１０μｍ以上５００μｍ以下とすることができる。 Examples of the lithium storage material include metallic lithium, alloys containing metallic lithium and other elements (silicon, tin, indium, etc.), oxides such as silicon or tin that can be charged and discharged at a low potential close to lithium, Li 4 Ti 5 O Examples thereof include an oxide of lithium and titanium such as 12 (LTO), a nitride of lithium and cobalt such as Li 2.6 Co 0.4 N, and TiO 2 (titania). When using the LTO or TiO 2 as a lithium occlusion material, the negative electrode layer 108 may be composed of sintered plate by a plurality of anode active material crystal grains (primary particles) binds. It should be noted that the composition formula of the lithium occlusion material naturally changes according to the occlusion and release of lithium ions. When a lithium storage material is used as the negative electrode active material, the thickness of the negative electrode layer 108 can be 10 μm or more and 500 μm or less.
　負極活物質として炭素質材料やリチウム吸蔵物質を用いる場合、負極層１０８は、ＥＰＤ法で作製することが好ましい。これによって、スパッタリング法やＣＶＤ法などに比べて低温で負極層１０８を作製できるため、負極層１０８中の活物質と固体電解質層１０７中の第１又は第２固体電解質とが反応して高抵抗層が形成されることを抑制できる。 When a carbonaceous material or a lithium storage material is used as the negative electrode active material, the negative electrode layer 108 is preferably manufactured by the EPD method. As a result, the negative electrode layer 108 can be fabricated at a lower temperature than in the sputtering method, the CVD method, or the like. Therefore, the active material in the negative electrode layer 108 reacts with the first or second solid electrolyte in the solid electrolyte layer 107 to increase resistance. Formation of a layer can be suppressed.
　なお、負極層１０８の形成には、負極層１０８の材料に応じて、テープ成形法、印刷法、スピンコート法などを用いてもよい。 Note that the negative electrode layer 108 may be formed by a tape molding method, a printing method, a spin coating method, or the like depending on the material of the negative electrode layer 108.
　また、負極層１０８には、箔状のリチウム吸蔵部材（Ｓｎ箔やＬｉ箔など）を用いることができる。この場合、固体電解質層１０７上に箔状のリチウム吸蔵部材をプレス成形することによって、負極層１０８を作製することができる。この場合においても、負極層１０８中の活物質と固体電解質層１０７中の第１又は第２固体電解質とが反応して高抵抗層が形成されることを抑制できる。 Further, a foil-like lithium storage member (such as Sn foil or Li foil) can be used for the negative electrode layer 108. In this case, the negative electrode layer 108 can be produced by press-molding a foil-like lithium occlusion member on the solid electrolyte layer 107. Also in this case, it can be suppressed that the active material in the negative electrode layer 108 reacts with the first or second solid electrolyte in the solid electrolyte layer 107 to form a high resistance layer.
　（他の実施形態）
　（１）上記実施形態において、正極層１０６（第１電極の一例）は、正極活物質結晶粒によって構成されることとしたが、正極活物質に加えて、上述した固体電解質層１０７の構成物質（第１固体電解質と第２固体電解質）を含有していることが好ましい。これによって、正極層１０６と固体電解質層１０７との間におけるイオン伝導性を向上させることができるため、リチウムイオン電池１００の内部抵抗を低減させることができる。この場合、正極層１０６における第１固体電解質と第２固体電解質との合計含有率は３０ｗｔ％以上が好ましく、正極層１０６における第２固体電解質の平均含有率は４ｗｔ％以上２０ｗｔ％以下が好ましい。これによって、正極層１０６の気孔率を、９％以下にすることができる。 (Other embodiments)
(1) In the above embodiment, the positive electrode layer 106 (an example of the first electrode) is composed of the positive electrode active material crystal grains, but in addition to the positive electrode active material, the constituent material of the solid electrolyte layer 107 described above It is preferable to contain (first solid electrolyte and second solid electrolyte). As a result, the ion conductivity between the positive electrode layer 106 and the solid electrolyte layer 107 can be improved, so that the internal resistance of the lithium ion battery 100 can be reduced. In this case, the total content of the first solid electrolyte and the second solid electrolyte in the positive electrode layer 106 is preferably 30 wt% or more, and the average content of the second solid electrolyte in the positive electrode layer 106 is preferably 4 wt% or more and 20 wt% or less. Thereby, the porosity of the positive electrode layer 106 can be 9% or less.
　正極層１０６における第１固体電解質と第２固体電解質との合計含有率は、４０ｗｔ％以上がより好ましく、５０ｗｔ％以上が特に好ましい。正極層１０６における第２固体電解質の平均含有率は、５ｗｔ％以上１５ｗｔ％以下がより好ましく、７ｗｔ％以上１２ｗｔ％以下が特に好ましい。固体電解質層１０７の構成物質（第１固体電解質と第２固体電解質）を含有する正極層１０６は、固体電解質層１０７と同様の手法で作製することができる。 The total content of the first solid electrolyte and the second solid electrolyte in the positive electrode layer 106 is more preferably 40 wt% or more, and particularly preferably 50 wt% or more. The average content of the second solid electrolyte in the positive electrode layer 106 is more preferably 5 wt% or more and 15 wt% or less, and particularly preferably 7 wt% or more and 12 wt% or less. The positive electrode layer 106 containing the constituent materials (the first solid electrolyte and the second solid electrolyte) of the solid electrolyte layer 107 can be produced in the same manner as the solid electrolyte layer 107.
　（２）上記実施形態において、負極層１０８（第１電極の一例）は、炭素質材料やリチウム吸蔵物質などの負極活物質によって構成できることとしたが、負極活物質に加えて、上述した固体電解質層１０７の構成物質（第１固体電解質と第２固体電解質）を含有していることが好ましい。これによって、負極層１０８と固体電解質層１０７との間におけるイオン伝導性を向上させることができるため、リチウムイオン電池１００の内部抵抗を低減させることができる。この場合、負極層１０８における第１固体電解質と第２固体電解質との合計含有率は３０ｗｔ％以上が好ましく、負極層１０８における第２固体電解質の平均含有率は４ｗｔ％以上２０ｗｔ％以下が好ましい。これによって、負極層１０８の気孔率を、９％以下にすることができる。 (2) In the embodiment described above, the negative electrode layer 108 (an example of the first electrode) can be composed of a negative electrode active material such as a carbonaceous material or a lithium storage material. However, in addition to the negative electrode active material, the solid electrolyte described above is used. It is preferable that the constituent materials of the layer 107 (first solid electrolyte and second solid electrolyte) are contained. Thereby, since the ion conductivity between the negative electrode layer 108 and the solid electrolyte layer 107 can be improved, the internal resistance of the lithium ion battery 100 can be reduced. In this case, the total content of the first solid electrolyte and the second solid electrolyte in the negative electrode layer 108 is preferably 30 wt% or more, and the average content of the second solid electrolyte in the negative electrode layer 108 is preferably 4 wt% or more and 20 wt% or less. Thereby, the porosity of the negative electrode layer 108 can be reduced to 9% or less.
　負極層１０８における第１固体電解質と第２固体電解質との合計含有率は、４０ｗｔ％以上がより好ましく、５０ｗｔ％以上が特に好ましい。負極層１０８における第２固体電解質の平均含有率は、１０ｗｔ％以上１５ｗｔ％以下が特に好ましい。固体電解質層１０７の構成物質（第１固体電解質と第２固体電解質）を含有する負極層１０８は、固体電解質層１０７と同様の手法で作製することができる。 The total content of the first solid electrolyte and the second solid electrolyte in the negative electrode layer 108 is more preferably 40 wt% or more, and particularly preferably 50 wt% or more. The average content of the second solid electrolyte in the negative electrode layer 108 is particularly preferably 10 wt% or more and 15 wt% or less. The negative electrode layer 108 containing the constituent materials (the first solid electrolyte and the second solid electrolyte) of the solid electrolyte layer 107 can be manufactured in the same manner as the solid electrolyte layer 107.
　（３）上記実施形態では、正極層１０６と固体電解質層１０７とが直接接触することとしたが、これに限られるものではない。正極層１０６と固体電解質層１０７との間には、固体電解質層１０７の第２固体電解質として用いることのできる固体電解質（酸化物系セラミックス材料、可塑性材料、又はこれらの組み合わせ）によって構成される第１中間層が介挿されていてもよい。第１中間層を構成する固体電解質は、固体電解質層１０７が副成分として含有する第２固体電解質と異なっていてもよいが、同じであることが好ましい。第１中間層の厚みは特に制限されないが、例えば１μｍ以上５μｍ以下とすることができる。このような第１中間層を介挿することによって、正極層１０６と固体電解質層１０７との密着性が向上するため、正極層１０６と固体電解質層１０７との間の抵抗を低減させることができる。 (3) In the above embodiment, the positive electrode layer 106 and the solid electrolyte layer 107 are in direct contact with each other. However, the present invention is not limited to this. Between the positive electrode layer 106 and the solid electrolyte layer 107, a solid electrolyte (oxide-based ceramic material, plastic material, or a combination thereof) that can be used as the second solid electrolyte of the solid electrolyte layer 107 is provided. One intermediate layer may be interposed. The solid electrolyte constituting the first intermediate layer may be different from the second solid electrolyte contained in the solid electrolyte layer 107 as a subcomponent, but is preferably the same. The thickness of the first intermediate layer is not particularly limited, and can be, for example, 1 μm or more and 5 μm or less. By interposing such a first intermediate layer, the adhesion between the positive electrode layer 106 and the solid electrolyte layer 107 is improved, so that the resistance between the positive electrode layer 106 and the solid electrolyte layer 107 can be reduced. .
　（４）上記実施形態では、負極層１０８と固体電解質層１０７とが直接接触することとしたが、これに限られるものではない。負極層１０８と固体電解質層１０７との間には、固体電解質層１０７の第２固体電解質として用いることのできる固体電解質（酸化物系セラミックス材料、可塑性材料、又はこれらの組み合わせ）によって構成される第２中間層が介挿されていてもよい。第２中間層を構成する固体電解質は、固体電解質層１０７が副成分として含有する第２固体電解質と異なっていてもよいが、同じであることが好ましい。第２中間層の厚みは特に制限されないが、例えば１μｍ以上５μｍ以下とすることができる。このような第２中間層を介挿することによって、負極層１０８と固体電解質層１０７との密着性が向上するため、負極層１０８と固体電解質層１０７との間の抵抗を低減させることができる。 (4) In the above embodiment, the negative electrode layer 108 and the solid electrolyte layer 107 are in direct contact with each other. However, the present invention is not limited to this. Between the negative electrode layer 108 and the solid electrolyte layer 107, a solid electrolyte (oxide-based ceramic material, plastic material, or a combination thereof) that can be used as the second solid electrolyte of the solid electrolyte layer 107 is provided. Two intermediate layers may be interposed. The solid electrolyte constituting the second intermediate layer may be different from the second solid electrolyte contained in the solid electrolyte layer 107 as a subcomponent, but is preferably the same. The thickness of the second intermediate layer is not particularly limited, and can be, for example, 1 μm or more and 5 μm or less. By interposing such a second intermediate layer, the adhesion between the negative electrode layer 108 and the solid electrolyte layer 107 is improved, so that the resistance between the negative electrode layer 108 and the solid electrolyte layer 107 can be reduced. .
　（５）上記実施形態では特に触れていないが、正極層１０６と固体電解質層１０７との間には、公知の有機電解液が介挿されていてもよい。これによって、正極層１０６と固体電解質層１０７との接合性を向上させることができる。同様に、負極層１０８と固体電解質層１０７との間には、公知の有機電解液が介挿されていてもよい。これによって、負極層１０８と固体電解質層１０７との接合性を向上させることができる。 (5) Although not particularly mentioned in the above embodiment, a known organic electrolytic solution may be interposed between the positive electrode layer 106 and the solid electrolyte layer 107. Thereby, the bondability between the positive electrode layer 106 and the solid electrolyte layer 107 can be improved. Similarly, a known organic electrolyte solution may be interposed between the negative electrode layer 108 and the solid electrolyte layer 107. Thereby, the bondability between the negative electrode layer 108 and the solid electrolyte layer 107 can be improved.
　（６）上記実施形態では特に触れていないが、正極層１０６、固体電解質層１０７及び負極層１０８の少なくとも１つは、公知の有機電解液を含有していてもよい。これによって、有機電解液を含有する層を構成する粒子どうしの接合性を向上させることができる。有機電解液を含有する層における有機電解液の含有率は特に制限されないが、９％以下とした場合には、気孔内に有機電解液を配置することができるため好ましい。有機電解液を含有する層における有機電解液の含有率は、各層の断面において、厚み方向に各層を５等分する４箇所で有機電解液の含有率を測定し、それを算術平均することによって得られる。有機電解液の含有率は、各測定箇所において２００００倍率のＳＥＭ画像を取得し、当該ＳＥＭ画像内における有機電解液の合計面積を層全体の面積で除することによって算出される。 (6) Although not particularly mentioned in the above embodiment, at least one of the positive electrode layer 106, the solid electrolyte layer 107, and the negative electrode layer 108 may contain a known organic electrolytic solution. Thereby, it is possible to improve the bonding property between the particles constituting the layer containing the organic electrolyte. Although the content rate of the organic electrolyte solution in the layer containing the organic electrolyte solution is not particularly limited, it is preferably 9% or less because the organic electrolyte solution can be disposed in the pores. The content of the organic electrolyte in the layer containing the organic electrolyte is obtained by measuring the content of the organic electrolyte at four locations that divide each layer into 5 parts in the thickness direction in the cross section of each layer, and arithmetically averaging it. can get. The content rate of the organic electrolyte is calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the organic electrolyte in the SEM image by the area of the entire layer.
　以下において本発明に係るリチウムイオン電池の実施例について説明するが、本発明は以下に説明する実施例に限定されるものではない。 Hereinafter, examples of the lithium ion battery according to the present invention will be described, but the present invention is not limited to the examples described below.
　１．固体電解質層の緻密化試験
　（実施例１～８）
　以下のようにして、実施例１～８に係るリチウムイオン電池を作製した。 1. Densification test of solid electrolyte layer (Examples 1 to 8)
The lithium ion batteries according to Examples 1 to 8 were produced as follows.
　１．正極層の作製
　Ｃｏ３Ｏ４原料粉末（体積基準Ｄ５０粒径０．８μｍ、正同化学工業株式会社製）とＬｉ２ＣＯ３原料粉末（体積基準Ｄ５０粒径２．５μｍ、本荘ケミカル製）を混合し、８００℃で５時間焼成することでＬｉＣｏＯ２原料粉末を合成した。 1. Preparation of positive electrode layer Co 3 O 4 raw material powder (volume basis D50 particle size 0.8 μm, manufactured by Shodo Chemical Co., Ltd.) and Li 2 CO 3 raw material powder (volume basis D50 particle size 2.5 μm, manufactured by Honjo Chemical) mixed and synthesized LiCoO 2 raw powder by calcining for 5 hours at 800 ° C..
　次に、得られたＬｉＣｏＯ２粉末を粉砕することによって板状ＬｉＣｏＯ２粒子（ＬＣＯテンプレート粒子）を得た。また、マトリックス粒子として、Ｃｏ３Ｏ４（ＣｏＯ）原料粉末（正同化学工業株式会社製）を準備した。 Next, the obtained LiCoO 2 powder was pulverized to obtain plate-like LiCoO 2 particles (LCO template particles). Moreover, Co 3 O 4 (CoO) raw material powder (manufactured by Shodo Chemical Industry Co., Ltd.) was prepared as matrix particles.
　次に、ＬＣＯテンプレート粒子とＣｏＯマトリックス粒子の混合粉末１００重量部と、分散媒（トルエン：イソプロパノール＝１：１）１００重量部と、バインダー（ポリビニルブチラール：品番ＢＭ－２、積水化学工業株式会社製）１０重量部と、可塑剤（ＤＯＰ：Ｄｉ（２－ｅｔｈｙｌｈｅｘｙｌ）ｐｈｔｈａｌａｔｅ、黒金化成株式会社製）４重量部と、分散剤（製品名レオドールＳＰ－Ｏ３０、花王株式会社製）２重量部とを混合した。この混合物を、減圧下で撹拌することで脱泡するとともに粘度を４０００１００００ｃＰに調整することによってスラリーを調製した。 Next, 100 parts by weight of a mixed powder of LCO template particles and CoO matrix particles, 100 parts by weight of a dispersion medium (toluene: isopropanol = 1: 1), and a binder (polyvinyl butyral: product number BM-2, manufactured by Sekisui Chemical Co., Ltd.) ) 10 parts by weight, 4 parts by weight of a plasticizer (DOP: Di (2-ethylhexyl) phthalate, manufactured by Kurokin Kasei Co., Ltd.), and 2 parts by weight of a dispersant (product name: Leodol SP-O30, manufactured by Kao Corporation) Were mixed. The mixture was degassed by stirring under reduced pressure, and a slurry was prepared by adjusting the viscosity to 40960000 cP.
　次に、ＰＥＴフィルムから剥がしたグリーンシートをジルコニア製セッターに載置して一次焼成することによってＣｏ３Ｏ４焼結板を得た。そして、Ｃｏ３Ｏ４焼結板をリチウムシートで上下挟み込んだ状態でジルコニアセッター上に載せて二次焼成することによって、正極層としてのＬｉＣｏＯ２（ＬＣＯ）焼結板を得た。ＬＣＯ焼結板の厚みは５０μｍであった。 Next, the green sheet peeled from the PET film was placed on a zirconia setter and subjected to primary firing to obtain a Co 3 O 4 sintered plate. The Co 3 O 4 sintered plate was placed on a zirconia setter while being sandwiched between upper and lower lithium sheets and subjected to secondary firing to obtain a LiCoO 2 (LCO) sintered plate as a positive electrode layer. The thickness of the LCO sintered plate was 50 μm.
　２．固体電解質層の成形体の作製
　表１に示す主成分（第１固体電解質）と副成分（第２固体電解質）との混合物を得た。実施例１～５では、主成分としてＬｉ（Ａｌ，Ｔｉ）２（ＰＯ４）３（ＬＡＴＰ）を用い、副成分としてＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３（３０ｗｔ％：７０ｗｔ％）を用いた。実施例６では、主成分としてＬｉ７Ｌａ３Ｔａ２Ｏ１２（ＬＬＴ）を用い、副成分としてＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３（３０ｗｔ％：７０ｗｔ％）を用いた。実施例７では、主成分としてＬＡＴＰを用い、副成分としてＬｉＰＯ３を用いた。実施例８では、主成分としてＬＡＴＰを用い、副成分としてＬｉ３ＢＯ３を用いた。実施例１～８の副成分は、酸化物系セラミックス材料である。なお、副成分の混合割合は、表１に記載のとおり、３～４０ｗｔ％の間で変更した。 2. Production of molded body of solid electrolyte layer A mixture of the main component (first solid electrolyte) and the subcomponent (second solid electrolyte) shown in Table 1 was obtained. In Examples 1 to 5, Li (Al, Ti) 2 (PO 4 ) 3 (LATP) was used as the main component, and Li 4 SiO 4 —Li 3 BO 3 (30 wt%: 70 wt%) was used as the subcomponent. . In Example 6, Li 7 La 3 Ta 2 O 12 (LLT) was used as the main component, and Li 4 SiO 4 —Li 3 BO 3 (30 wt%: 70 wt%) was used as the subcomponent. In Example 7, using LATP as the main component, it was used LiPO 3 as an auxiliary component. In Example 8, LATP was used as the main component, and Li 3 BO 3 was used as the subcomponent. The subcomponents of Examples 1 to 8 are oxide ceramic materials. The mixing ratio of the subcomponents was changed between 3 and 40 wt% as shown in Table 1.
　次に、得られた混合物をＬｉＣｏＯ２焼結板の表面に印刷することによって、固体電解質層の成形体を作製した。 Next, the obtained mixture was printed on the surface of the LiCoO 2 sintered plate to produce a solid electrolyte layer compact.
　３．負極層の成形体の作製
　活物質としてのＬｉ４Ｔｉ５Ｏ１２（ＬＴＯ）粉末と固体電解質層の主成分と固体電解質層の副成分との混合物を得た。なお、副成分の混合割合は、表１に記載のとおり、４～２０ｗｔ％の間で変更した。 3. Preparation of molded body of negative electrode layer A mixture of Li 4 Ti 5 O 12 (LTO) powder as an active material, the main component of the solid electrolyte layer, and the subcomponent of the solid electrolyte layer was obtained. The mixing ratio of the subcomponents was changed between 4 and 20 wt% as shown in Table 1.
　次に、得られた混合物を固体電解質層の成形体の表面に印刷することによって、負極層の成形体を作製した。 Next, the obtained mixture was printed on the surface of the solid electrolyte layer compact to produce a negative electrode layer compact.
　４．焼成
　正極層、固体電解質層の成形体及び負極層の成形体の積層体を一括して焼成することによって、固体電解質層及び負極層を形成した。正極層の厚みは５０μｍであった。固体電解質層の厚みは２０μｍであった。 4). Firing A solid electrolyte layer and a negative electrode layer were formed by collectively firing a laminate of a positive electrode layer, a solid electrolyte layer compact, and a negative electrode layer compact. The thickness of the positive electrode layer was 50 μm. The thickness of the solid electrolyte layer was 20 μm.
　実施例１～６では、副成分であるＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３の融点が５５０℃であるため、焼成温度を６００℃とした。実施例７では、副成分であるＬｉＰＯ３の融点が６６０℃であるため、焼成温度を７００℃とした。実施例８では、副成分であるＬｉ３ＢＯ３の融点が７１５℃であるため、焼成温度を７５０℃とした。 In Examples 1 to 6, since the melting point of Li 4 SiO 4 —Li 3 BO 3 which is a subcomponent is 550 ° C., the firing temperature was set to 600 ° C. In Example 7, since the melting point of LiPO 3 as the accessory component was 660 ° C., the firing temperature was 700 ° C. In Example 8, since the melting point of Li 3 BO 3 , which is a subcomponent, is 715 ° C., the firing temperature was 750 ° C.
　（実施例９，１０）
　正極層と固体電解質層の成形体との積層体を焼成して固体電解質層を形成した後に、箔状の負極層を固体電解質層上にプレス成形した以外は、実施例１～６と同様の工程により実施例９，１０に係るリチウムイオン電池を作製した。 (Examples 9 and 10)
The same as in Examples 1 to 6 except that the laminate of the positive electrode layer and the molded body of the solid electrolyte layer was fired to form the solid electrolyte layer, and then the foil-shaped negative electrode layer was press-molded on the solid electrolyte layer. Lithium ion batteries according to Examples 9 and 10 were produced according to the process.
　実施例９では、固体電解質層の主成分にＬｉ１．５Ａｌ０．５Ｇｅ１．５（ＰＯ４）３（ＬＡＧＰ）を用い、副成分にＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３を用いた。実施例９では、主成分と副成分とを７０ｗｔ％：３０ｗｔ％の割合で混合した。実施例１０では、固体電解質層の主成分にＬｉ７Ｌａ３Ｚｒ２Ｏ１２（ＬＬＺ）を用い、副成分にＬｉ３ＣｌＯを用いた。実施例１０では、主成分と副成分とを９０ｗｔ％：１０ｗｔ％の割合で混合した。Ｌｉ３ＣｌＯの融点は３５０℃であるため、実施例１０における焼成温度は３５０℃とした。 In Example 9, Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) was used as the main component of the solid electrolyte layer, and Li 4 SiO 4 —Li 3 BO 3 was used as the subcomponent. . In Example 9, the main component and the subcomponent were mixed at a ratio of 70 wt%: 30 wt%. In Example 10, Li 7 La 3 Zr 2 O 12 (LLZ) was used as the main component of the solid electrolyte layer, and Li 3 ClO was used as the subcomponent. In Example 10, the main component and the subcomponent were mixed at a ratio of 90 wt%: 10 wt%. Since the melting point of Li 3 ClO is 350 ° C., the firing temperature in Example 10 was set to 350 ° C.
　（実施例１１）
　カーボン粉末と固体電解質層の主成分及び副成分との混合物を固体電解質層上に印刷することによって負極層を形成した以外は、実施例１０と同様の工程により実施例１１に係るリチウムイオン電池を作製した。実施例１１の負極層では、カーボン粉と固体電解質層の主成分であるＬＬＺと副成分であるＬｉ３ＣｌＯとを５０ｗｔ％：４０ｗｔ％：１０ｗｔ％の割合で混合した。 (Example 11)
The lithium ion battery according to Example 11 was manufactured in the same manner as in Example 10 except that the negative electrode layer was formed by printing a mixture of the carbon powder and the main component and subcomponent of the solid electrolyte layer on the solid electrolyte layer. Produced. In the negative electrode layer of Example 11, LLZ which is the main component of the carbon powder and the solid electrolyte layer and Li 3 ClO which is the subcomponent were mixed at a ratio of 50 wt%: 40 wt%: 10 wt%.
　（実施例１２）
　正極層、固体電解質層の成形体及び負極層の成形体の積層体を一括して一軸プレス（室温、２００ＭＰａ）することによって固体電解質層及び負極層を形成した以外は、実施例１～８と同様の工程により実施例１２に係るリチウムイオン電池を作製した。 (Example 12)
Except that the solid electrolyte layer and the negative electrode layer were formed by collectively uniaxially pressing the molded body of the positive electrode layer, the solid electrolyte layer and the negative electrode layer (room temperature, 200 MPa), and A lithium ion battery according to Example 12 was fabricated by the same process.
　実施例１２では、固体電解質層の主成分としてＬＡＧＰを用い、副成分としてＬｉ３ＡｌＦ６を用いた。実施例１２では、主成分と副成分とを９０ｗｔ％：１０ｗｔ％の割合で混合した。実施例１２の副成分は、可塑性材料である。 In Example 12, LAGP was used as the main component of the solid electrolyte layer, and Li 3 AlF 6 was used as the subcomponent. In Example 12, the main component and the subcomponent were mixed at a ratio of 90 wt%: 10 wt%. The accessory component of Example 12 is a plastic material.
　実施例１２では、ＬＡＧＰとＬｉ３ＡｌＦ６との混合物を、正極層上にＥＰＤ法を用いて堆積させることによって、固体電解質層の成形体を形成した。また、ＬＴＯ粉末とＬＡＧＰとＬｉ３ＡｌＦ６との混合物を、固体電解質層の成形体上にＥＰＤ法を用いて堆積させることによって、負極層の成形体を形成した。実施例１２の負極層では、ＬＴＯ粉末と固体電解質層の主成分であるＬＡＧＰと副成分であるＬｉ３ＡｌＦ６とを５０ｗｔ％：４５ｗｔ％：５ｗｔ％の割合にした。 In Example 12, a compact of the solid electrolyte layer was formed by depositing a mixture of LAGP and Li 3 AlF 6 on the positive electrode layer using the EPD method. Further, a mixture of LTO powder and LAGP and Li 3 AlF 6, by depositing with the EPD method on molded article of the solid electrolyte layer to form a molded body of the negative electrode layer. The negative electrode layer of Example 12, 50 wt% and a Li 3 AlF 6 is LAGP subcomponent is the main component of LTO powder and the solid electrolyte layer: 45 wt%: and the percentage of 5 wt%.
　（実施例１３）
　固体電解質層の副成分としてＢｉ２Ｏ３－Ｂ２Ｏ３（９０ｗｔ％：１０ｗｔ％）を用いた以外は、実施例９と同様の工程により実施例１３に係るリチウムイオン電池を作製した。 (Example 13)
A lithium ion battery according to Example 13 was fabricated by the same process as in Example 9, except that Bi 2 O 3 —B 2 O 3 (90 wt%: 10 wt%) was used as a subcomponent of the solid electrolyte layer.
　副成分として用いたＢｉ２Ｏ３－Ｂ２Ｏ３は、可塑性材料である。Ｂｉ２Ｏ３－Ｂ２Ｏ３の軟化点は３８９℃であるため、加熱温度は４００℃とした。 Bi 2 O 3 —B 2 O 3 used as an accessory component is a plastic material. Since the softening point of Bi 2 O 3 —B 2 O 3 is 389 ° C., the heating temperature was set to 400 ° C.
　（実施例１４～１８）
　固体電解質層の主成分としてＬＡＧＰを用い、副成分としてＮａＩ－ＬｉＢＨ４（９９ｗｔ％：１ｗｔ％）を用いた以外は、実施例１２と同様の工程により実施例１４～１８に係るリチウムイオン電池を作製した。副成分として用いたＮａＩ－ＬｉＢＨ４は、可塑性材料である。 (Examples 14 to 18)
The lithium ion batteries according to Examples 14 to 18 were manufactured in the same manner as in Example 12 except that LAGP was used as the main component of the solid electrolyte layer and NaI-LiBH 4 (99 wt%: 1 wt%) was used as the subcomponent. Produced. NaI—LiBH 4 used as an accessory component is a plastic material.
　実施例１４～１８では、ＬＡＧＰとＮａＩ－ＬｉＢＨ４との混合物を、正極層上にＥＰＤ法を用いて堆積させることによって、固体電解質層の成形体を形成した。また、ＬＴＯ粉末とＬＡＧＰとＮａＩ－ＬｉＢＨ４との混合物を、固体電解質層の成形体上にＥＰＤ法を用いて堆積させることによって、負極層の成形体を形成した。実施例１４～１８の負極層では、ＬＴＯ粉末と固体電解質層の主成分であるＬＡＧＰと副成分であるＮａＩ－ＬｉＢＨ４とを５０ｗｔ％：４５ｗｔ％：５ｗｔ％の割合にした。 In Examples 14 to 18, a mixture of LAGP and NaI-LiBH 4 was deposited on the positive electrode layer using the EPD method, thereby forming a solid electrolyte layer compact. Further, a mixture of LTO powder and LAGP and NaI-LiBH 4, by depositing with the EPD method on molded article of the solid electrolyte layer to form a molded body of the negative electrode layer. In the negative electrode layers of Examples 14 to 18, LTO powder, LAGP, which is the main component of the solid electrolyte layer, and NaI—LiBH 4 which is the subcomponent were mixed at a ratio of 50 wt%: 45 wt%: 5 wt%.
　（実施例１９）
　正極層と固体電解質層との間に、固体電解質層の副成分であるＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３（３０ｗｔ％：７０ｗｔ％）によって構成される第１中間層（厚み１μｍ）を介挿し、負極層と固体電解質層との間に、固体電解質層の副成分であるＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３（３０ｗｔ％：７０ｗｔ％）によって構成される第２中間層（厚み１μｍ）を介挿した以外は、実施例２と同様の工程により実施例１９に係るリチウムイオン電池を作製した。ただし、実施例１９では、ＬＴＯ焼結板を負極層として用いた。 (Example 19)
A first intermediate layer (thickness 1 μm) composed of Li 4 SiO 4 —Li 3 BO 3 (30 wt%: 70 wt%), which is a subcomponent of the solid electrolyte layer, is interposed between the positive electrode layer and the solid electrolyte layer. In addition, a second intermediate layer (thickness: 1 μm) composed of Li 4 SiO 4 —Li 3 BO 3 (30 wt%: 70 wt%), which is a subcomponent of the solid electrolyte layer, is interposed between the negative electrode layer and the solid electrolyte layer. A lithium ion battery according to Example 19 was fabricated by the same process as in Example 2 except that it was inserted. However, in Example 19, an LTO sintered plate was used as the negative electrode layer.
　（実施例２０）
　正極層と固体電解質層との間に、固体電解質層の副成分であるＬｉ３ＡｌＦ６によって構成される第１中間層（厚み２μｍ）を介挿し、負極層と固体電解質層との間に、固体電解質層の副成分であるＬｉ３ＡｌＦ６によって構成される第２中間層（厚み２μｍ）を介挿した以外は、実施例１２と同様の工程により実施例２０に係るリチウムイオン電池を作製した。ただし、実施例２０では、主成分と副成分とを７０ｗｔ％：３０ｗｔ％の割合で混合し、ＬＴＯ焼結板を負極層として用いた。 (Example 20)
Between the positive electrode layer and the solid electrolyte layer, a first intermediate layer (thickness 2 μm) composed of Li 3 AlF 6 which is a subcomponent of the solid electrolyte layer is interposed, and between the negative electrode layer and the solid electrolyte layer, A lithium ion battery according to Example 20 was produced by the same process as Example 12 except that a second intermediate layer (thickness 2 μm) constituted by Li 3 AlF 6 which is a subcomponent of the solid electrolyte layer was interposed. . However, in Example 20, the main component and the subcomponent were mixed at a ratio of 70 wt%: 30 wt%, and the LTO sintered plate was used as the negative electrode layer.
　（比較例１，２）
　固体電解質層に副成分を添加しなかった以外は、実施例１と同様の工程により比較例１，２に係るリチウムイオン電池を作製した。ただし、比較例１では焼成温度を５００℃とし、比較例２では焼成温度を９００℃とした。 (Comparative Examples 1 and 2)
Lithium ion batteries according to Comparative Examples 1 and 2 were produced in the same manner as in Example 1 except that no subcomponent was added to the solid electrolyte layer. However, in Comparative Example 1, the firing temperature was 500 ° C., and in Comparative Example 2, the firing temperature was 900 ° C.
　（固体電解質層の平均気孔率の測定）
　ＣＰ研磨した固体電解質層の断面において、厚み方向に固体電解質層を５等分する４箇所で気孔率を測定し、それを算術平均することによって、実施例１～２０及び比較例１～２それぞれの固体電解質層における平均気孔率を得た。固体電解質層の平均気孔率を表１にまとめて示す。 (Measurement of average porosity of solid electrolyte layer)
In the cross section of the solid electrolyte layer subjected to the CP polishing, the porosity was measured at four locations where the solid electrolyte layer was equally divided into five in the thickness direction, and the results were arithmetically averaged, whereby each of Examples 1 to 20 and Comparative Examples 1 and 2 The average porosity in the solid electrolyte layer was obtained. Table 1 summarizes the average porosity of the solid electrolyte layer.
　なお、気孔率は、各測定箇所における２００００倍率のＳＥＭ画像を取得し、固体電解質層内における気孔の合計面積を全体面積で除することによって算出した。 In addition, the porosity was calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the pores in the solid electrolyte layer by the total area.
　（電池内部抵抗の測定）
　交流インピーダンス法を用いて、実施例１～２０及び比較例１～２それぞれの電池内部抵抗を室温にて測定した。電池内部抵抗の測定には、バイオロジック社製マルチポテンショガルバノスタットにバイオロジック社製周波数応答アナライザを接続したものを用いた。測定結果を表１にまとめて示す。 (Measurement of battery internal resistance)
Using the AC impedance method, the battery internal resistances of Examples 1 to 20 and Comparative Examples 1 and 2 were measured at room temperature. For measuring the internal resistance of the battery, a biologic multi-potential galvanostat connected to a biologic frequency response analyzer was used. The measurement results are summarized in Table 1.
Figure JPOXMLDOC01-appb-T000001
  
Figure JPOXMLDOC01-appb-T000001
  
　表１に示すように、実施例１～１１，１９では、固体電解質層に含まれる第２固体電解質（酸化物系セラミックス材料）の融点以上で焼成することによって固体電解質層を緻密化できたため、固体電解質層の平均気孔率を９％以下にすることができた。また、実施例１２～１８，２０では、固体電解質層に含まれる第２固体電解質（可塑性材料）を塑性変形させることによって固体電解質層を緻密化できたため、固体電解質層の平均気孔率を９％以下にすることができた。 As shown in Table 1, in Examples 1 to 11 and 19, the solid electrolyte layer was densified by firing at a temperature equal to or higher than the melting point of the second solid electrolyte (oxide-based ceramic material) contained in the solid electrolyte layer. The average porosity of the solid electrolyte layer could be 9% or less. In Examples 12 to 18, and 20, since the solid electrolyte layer could be densified by plastic deformation of the second solid electrolyte (plastic material) contained in the solid electrolyte layer, the average porosity of the solid electrolyte layer was 9%. I was able to:
　一方、比較例１，２では、固体電解質層が第２固体電解質を含有しておらず、固体電解質層を緻密化できなかったため、固体電解質層の平均気孔率は３０％以上であった。 On the other hand, in Comparative Examples 1 and 2, since the solid electrolyte layer did not contain the second solid electrolyte and the solid electrolyte layer could not be densified, the average porosity of the solid electrolyte layer was 30% or more.
　そのため、実施例１～２０では、比較例１～２に比べて、固体電解質層のイオン伝導性を向上させることによって電池内部抵抗を低減できた。 Therefore, in Examples 1 to 20, the internal resistance of the battery could be reduced by improving the ionic conductivity of the solid electrolyte layer as compared with Comparative Examples 1 and 2.
　特に、酸化物系セラミックス材料を固体電解質の第２固体電解質に用いた実施例１～１１，１９のうち焼成温度を６００℃以下にした実施例１～６，９～１１，１９と、可塑性材料を固体電解質の第２固体電解質に用いた実施例１２～１８，２０では、電池内部抵抗をより低減させることができた。これは、低温プロセスで固体電解質層を形成することによって、正極層又は負極層の活物質と固体電解質とが反応して高抵抗層が形成されることを抑制できたためである。 In particular, among Examples 1 to 11 and 19 in which an oxide-based ceramic material is used for the second solid electrolyte of the solid electrolyte, Examples 1 to 6, 9 to 11 and 19 in which the firing temperature is 600 ° C. or less, and a plastic material In Examples 12 to 18 and 20, in which was used for the second solid electrolyte of the solid electrolyte, the battery internal resistance could be further reduced. This is because the formation of the solid electrolyte layer by a low-temperature process can suppress the formation of the high resistance layer by reacting the active material of the positive electrode layer or the negative electrode layer with the solid electrolyte.
　また、酸化物系セラミックス材料を第２固体電解質に用い、かつ、焼成温度を６００℃以下にした実施例１～６，９～１１，１９のうち、第２固体電解質の平均含有率を４ｗｔ％以上３０ｗｔ％以下にした実施例１～３，６，９～１１，１９では、固体電解質層の平均気孔率を７％以下にすることができた。 In Examples 1 to 6, 9 to 11, 19 in which the oxide ceramic material was used for the second solid electrolyte and the firing temperature was 600 ° C. or less, the average content of the second solid electrolyte was 4 wt%. In Examples 1 to 3, 6, 9 to 11, 19 in which the content was 30 wt% or less, the average porosity of the solid electrolyte layer could be 7% or less.
　また、固体電解質層の第２固体電解質に可塑性材料を用いた実施例１２～１８，２０のうち、第２固体電解質の平均含有率を４ｗｔ％以上３０ｗｔ％以下にした実施例１２～１６，２０では、固体電解質層の平均気孔率を７％以下にすることができた。 Of Examples 12 to 18 and 20 in which a plastic material is used for the second solid electrolyte of the solid electrolyte layer, Examples 12 to 16 and 20 in which the average content of the second solid electrolyte is 4 wt% or more and 30 wt% or less. Then, the average porosity of the solid electrolyte layer could be reduced to 7% or less.
　また、固体電解質層の第２固体電解質によって構成される第１及び第２中間層が設けられた実施例１９，２０では、実施例２に比べて電池内部抵抗を更に低減することができた。これは、第１中間層によって正極層と固体電解質層との密着性を向上させ、また、第２中間層によって負極層と固体電解質層との密着性を向上させることができたためである。 Further, in Examples 19 and 20 in which the first and second intermediate layers constituted by the second solid electrolyte of the solid electrolyte layer were provided, the battery internal resistance could be further reduced as compared with Example 2. This is because the adhesion between the positive electrode layer and the solid electrolyte layer can be improved by the first intermediate layer, and the adhesion between the negative electrode layer and the solid electrolyte layer can be improved by the second intermediate layer.
　２．正極層及び負極層の緻密化試験
　（実施例２１，２２）
　ＬＣＯ粉末と固体電解質層の主成分と固体電解質層の副成分との混合物をテープ成形法で成形することによって正極層の成形体を作製した以外は、実施例１と同様の工程により実施例２１，２２に係るリチウムイオン電池を作製した。 2. Densification test of positive electrode layer and negative electrode layer (Examples 21 and 22)
Example 21 was performed in the same manner as in Example 1 except that a molded body of the positive electrode layer was produced by molding a mixture of the LCO powder, the main component of the solid electrolyte layer, and the subcomponent of the solid electrolyte layer by a tape molding method. , 22 were produced.
　実施例２１，２２の正極層では、固体電解質層の主成分にＬｉ１．５Ａｌ０．５Ｇｅ１．５（ＰＯ４）３（ＬＡＧＰ）を用い、副成分にＬｉ４ＳｉＯ４－Ｌｉ３ＢＯ３を用いた。実施例２１では、ＬＣＯ粉と固体電解質層の主成分と副成分とを、５０ｗｔ％：４６ｗｔ％：４ｗｔ％の割合で混合した。実施例２２では、ＬＣＯ粉と固体電解質層の主成分と副成分とを、７０ｗｔ％：１０ｗｔ％：２０ｗｔ％の割合で混合した。 The positive electrode layer of Example 21,22, Li 1.5 Al 0.5 Ge 1.5 using (PO 4) 3 (LAGP) in the main component of the solid electrolyte layer, Li 4 SiO 4 -Li 3 to subcomponent BO 3 was used. In Example 21, the main component and subcomponent of the LCO powder and the solid electrolyte layer were mixed at a ratio of 50 wt%: 46 wt%: 4 wt%. In Example 22, the LCO powder, the main component and the subcomponent of the solid electrolyte layer were mixed at a ratio of 70 wt%: 10 wt%: 20 wt%.
　実施例２１，２２では、正極層、固体電解質層及び負極層それぞれの成形体を積層して一括焼成することによって、正極層、固体電解質層及び負極層を同時に形成した。 In Examples 21 and 22, the positive electrode layer, the solid electrolyte layer, and the negative electrode layer were simultaneously formed by laminating and respectively firing the positive electrode layer, the solid electrolyte layer, and the negative electrode layer.
　（実施例２３～２７）
　ＬＴＯ焼結板を負極層として用いた以外は、実施例２１，２２と同様の工程により実施例２３～２７に係るリチウムイオン電池を作製した。なお、正極層における正極活物質と固体電解質（主成分及び副成分）との混合割合は、表２に記載のとおり、実施例ごとに変更した。 (Examples 23 to 27)
Lithium ion batteries according to Examples 23 to 27 were fabricated by the same process as in Examples 21 and 22, except that an LTO sintered plate was used as the negative electrode layer. In addition, as shown in Table 2, the mixing ratio of the positive electrode active material and the solid electrolyte (main component and subcomponent) in the positive electrode layer was changed for each example.
　（実施例２８～３２）
　ＬＣＯ焼結板を正極層として用いた以外は、実施例２１，２２と同様の工程により実施例２８～３２に係るリチウムイオン電池を作製した。なお、負極層における負極活物質と固体電解質（主成分及び副成分）との混合割合は、表２に記載のとおり、実施例ごとに変更した。 (Examples 28 to 32)
Lithium ion batteries according to Examples 28 to 32 were produced in the same manner as in Examples 21 and 22, except that an LCO sintered plate was used as the positive electrode layer. In addition, as shown in Table 2, the mixing ratio of the negative electrode active material and the solid electrolyte (main component and subcomponent) in the negative electrode layer was changed for each example.
　（比較例３）
　ＬＣＯ粉と固体電解質層の主成分と副成分とを５０ｗｔ％：４８ｗｔ％：２ｗｔ％の割合で混合することによって正極層の成形体を形成した以外は、実施例２１と同様の工程により比較例３に係るリチウムイオン電池を作製した。 (Comparative Example 3)
A comparative example was produced in the same manner as in Example 21 except that the molded body of the positive electrode layer was formed by mixing the main component and subcomponent of the LCO powder and the solid electrolyte layer in a ratio of 50 wt%: 48 wt%: 2 wt%. The lithium ion battery which concerns on 3 was produced.
　（比較例４）
　ＬＣＯ粉と固体電解質層の主成分と副成分とを５０ｗｔ％：４８ｗｔ％：２ｗｔ％の割合で混合することによって負極層の成形体を形成した以外は、実施例２８と同様の工程により比較例４に係るリチウムイオン電池を作製した。 (Comparative Example 4)
Comparative example according to the same steps as in Example 28 except that the molded body of the negative electrode layer was formed by mixing the main component and subcomponent of the LCO powder and the solid electrolyte layer in a ratio of 50 wt%: 48 wt%: 2 wt%. The lithium ion battery which concerns on 4 was produced.
　（正極層及び負極層の平均気孔率の測定）
　ＣＰ研磨した正極層の断面において、厚み方向に正極層を５等分する４箇所で気孔率を測定し、それを算術平均することによって、実施例２１～２７の正極層における平均気孔率を得た。 (Measurement of average porosity of positive electrode layer and negative electrode layer)
In the cross section of the CP-polished positive electrode layer, the porosity was measured at four locations that divide the positive electrode layer into 5 equal parts in the thickness direction, and the average porosity was obtained in the positive electrode layers of Examples 21 to 27 by arithmetic averaging. It was.
　また、ＣＰ研磨した負極層の断面において、厚み方向に負極層を５等分する４箇所で気孔率を測定し、それを算術平均することによって、実施例２１，２２，２８～３２の負極層における平均気孔率を得た。 In addition, in the cross section of the negative electrode layer polished by CP, the porosity was measured at four locations that divide the negative electrode layer into 5 equal parts in the thickness direction, and arithmetically averaged to obtain the negative electrode layers of Examples 21, 22, 28 to 32 The average porosity was obtained.
　なお、気孔率は、各測定箇所における２００００倍率のＳＥＭ画像を取得し、固体電解質層内における気孔の合計面積を全体面積で除することによって算出した。 In addition, the porosity was calculated by acquiring a SEM image at a magnification of 20000 at each measurement location and dividing the total area of the pores in the solid electrolyte layer by the total area.
　（電池内部抵抗の測定）
　交流インピーダンス法を用いて、実施例２１～３２及び比較例３～４それぞれの電池内部抵抗を室温にて測定した。電池内部抵抗の測定には、バイオロジック社製マルチポテンショガルバノスタットにバイオロジック社製周波数応答アナライザを接続したものを用いた。 (Measurement of battery internal resistance)
Using the AC impedance method, the battery internal resistances of Examples 21 to 32 and Comparative Examples 3 to 4 were measured at room temperature. For measuring the internal resistance of the battery, a biologic multi-potential galvanostat connected to a biologic frequency response analyzer was used.
Figure JPOXMLDOC01-appb-T000002
  
Figure JPOXMLDOC01-appb-T000002
  
　実施例２１～２７では、正極活物質に固体電解質層の主成分と副成分を添加することによって正極層を緻密化できたため、正極層の気孔率を９％以下に抑えることができた。一方、比較例３では、正極活物質に対して添加された固体電解質層の副成分が少なく正極層を緻密化できなかったため、正極層の平均気孔率は１０％であった。そのため、実施例２１～２７では、比較例３に比べて電池内部抵抗を低減できた。 In Examples 21 to 27, the positive electrode layer could be densified by adding the main component and subcomponents of the solid electrolyte layer to the positive electrode active material, so that the porosity of the positive electrode layer could be suppressed to 9% or less. On the other hand, in Comparative Example 3, since the minor component of the solid electrolyte layer added to the positive electrode active material was small and the positive electrode layer could not be densified, the average porosity of the positive electrode layer was 10%. Therefore, in Examples 21 to 27, the battery internal resistance could be reduced as compared with Comparative Example 3.
　また、実施例２１～２７のうち第２固体電解質の平均含有率を４ｗｔ％以上２０ｗｔ％以下にした実施例２１～２４では、電池内部抵抗を更に低減することができた。 Also, in Examples 21 to 24 in which the average content of the second solid electrolyte was 4 wt% or more and 20 wt% or less among Examples 21 to 27, the battery internal resistance could be further reduced.
　実施例２１，２２，２８～３２では、負極活物質に固体電解質層の主成分と副成分を添加することによって負極層を緻密化できたため、負極層の気孔率を９％以下に抑えることができた。一方、比較例４では、負極活物質に対して添加された固体電解質層の副成分が少なく負極層を緻密化できなかったため、負極層の平均気孔率は１０％であった。そのため、実施例２１，２２，２８～３２では、比較例４に比べて電池内部抵抗を低減できた。 In Examples 21, 22, 28 to 32, the negative electrode layer was densified by adding the main component and subcomponents of the solid electrolyte layer to the negative electrode active material, so that the porosity of the negative electrode layer was suppressed to 9% or less. did it. On the other hand, in Comparative Example 4, since the minor component of the solid electrolyte layer added to the negative electrode active material was small and the negative electrode layer could not be densified, the average porosity of the negative electrode layer was 10%. Therefore, in Examples 21, 22, 28 to 32, the battery internal resistance could be reduced as compared with Comparative Example 4.
　また、実施例２１，２２，２８～３２のうち第２固体電解質の平均含有率を４ｗｔ％以上２０ｗｔ％以下にした実施例２１，２２，２８，２９では、気孔率を６％以下に抑えるとともに、電池内部抵抗を更に低減することができた。 In Examples 21, 22, 28 to 32, in Examples 21, 22, 28, and 29 in which the average content of the second solid electrolyte was 4 wt% or more and 20 wt% or less, the porosity was suppressed to 6% or less. The battery internal resistance could be further reduced.
１００　　　　　リチウムイオン電池
１０１　　　　　正極側集電層
１０２　　　　　負極側集電層
１０３，１０４　外装材
１０５　　　　　集電接続層
１０６　　　　　正極層
１０７　　　　　固体電解質層
１０８　　　　　負極層
  DESCRIPTION OF SYMBOLS 100 Lithium ion battery 101 Positive electrode side current collection layer 102 Negative electrode side current collection layer 103,104 Exterior material 105 Current collection connection layer 106 Positive electrode layer 107 Solid electrolyte layer 108 Negative electrode layer

Claims (19)

  1. 　正極層と、
    　負極層と、
    　前記正極層と前記負極層との間に配置される固体電解質層と、
    を備え、
    　前記固体電解質層は、主成分である第１固体電解質と、副成分である第２固体電解質とを含有し、
    　前記固体電解質層の平均気孔率は、９％以下である、
    リチウムイオン電池。     A positive electrode layer;
    A negative electrode layer;
    A solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer;
    With
    The solid electrolyte layer contains a first solid electrolyte as a main component and a second solid electrolyte as a subcomponent,
    The average porosity of the solid electrolyte layer is 9% or less,
    Lithium ion battery.
  2. 　前記第２固体電解質の融点は、６００℃以下である、
    請求項１に記載のリチウムイオン電池。     The melting point of the second solid electrolyte is 600 ° C. or less.
    The lithium ion battery according to claim 1.
  3. 　前記固体電解質層における前記第２固体電解質の平均含有率は、４ｗｔ％以上３０ｗｔ％以下である、
    請求項２に記載のリチウムイオン電池。     The average content of the second solid electrolyte in the solid electrolyte layer is 4 wt% or more and 30 wt% or less.
    The lithium ion battery according to claim 2.
  4. 　前記第２固体電解質は、６００℃以下で可塑性を有する、
    請求項１に記載のリチウムイオン電池。     The second solid electrolyte has plasticity at 600 ° C. or lower,
    The lithium ion battery according to claim 1.
  5. 　前記固体電解質層における前記第２固体電解質の平均含有率は、４ｗｔ％以上３０ｗｔ％以下である、
    請求項４に記載のリチウムイオン電池。     The average content of the second solid electrolyte in the solid electrolyte layer is 4 wt% or more and 30 wt% or less.
    The lithium ion battery according to claim 4.
  6. 　前記固体電解質層は、実質的に硫黄を含有しない、
    請求項１乃至５のいずれかに記載のリチウムイオン電池。     The solid electrolyte layer is substantially free of sulfur;
    The lithium ion battery according to any one of claims 1 to 5.
  7. 　前記正極層は、正極活物質結晶粒によって構成される焼結板である、
    請求項１乃至６のいずれかに記載のリチウムイオン電池。     The positive electrode layer is a sintered plate composed of positive electrode active material crystal grains,
    The lithium ion battery according to claim 1.
  8. 　前記正極活物質結晶粒は、リチウム複合酸化物によって構成される、
    請求項７に記載のリチウムイオン電池。     The positive electrode active material crystal grains are composed of a lithium composite oxide.
    The lithium ion battery according to claim 7.
  9. 　前記負極層は、負極活物質結晶粒によって構成される焼結板である、
    請求項１乃至７のいずれかに記載のリチウムイオン電池。     The negative electrode layer is a sintered plate composed of negative electrode active material crystal grains,
    The lithium ion battery according to claim 1.
  10. 　前記負極活物質結晶粒は、リチウム複合酸化物によって構成される、
    請求項９に記載のリチウムイオン電池。     The negative electrode active material crystal grains are composed of a lithium composite oxide.
    The lithium ion battery according to claim 9.
  11. 　前記正極層と前記固体電解質層との間に介挿される第１中間層を備え、
    　前記第１中間層は、酸化物系セラミックス材料、可塑性材料、又はこれらの組み合わせによって構成される、
    請求項１乃至１０のいずれかに記載のリチウムイオン電池。     A first intermediate layer interposed between the positive electrode layer and the solid electrolyte layer;
    The first intermediate layer is composed of an oxide-based ceramic material, a plastic material, or a combination thereof.
    The lithium ion battery according to claim 1.
  12. 　前記負極層と前記固体電解質層との間に介挿される第２中間層を備え、
    　前記第２中間層は、酸化物系セラミックス材料、可塑性材料、又はこれらの組み合わせによって構成される、
    請求項１乃至１１のいずれかに記載のリチウムイオン電池。     A second intermediate layer interposed between the negative electrode layer and the solid electrolyte layer;
    The second intermediate layer is composed of an oxide-based ceramic material, a plastic material, or a combination thereof.
    The lithium ion battery according to claim 1.
  13. 　正極層と負極層との間に配置された固体電解質層を備えるリチウムイオン電池の製造方法であって、
    　主成分である第１固体電解質と副成分である第２固体電解質とを含有する前記固体電解質層の成形体を形成する工程と、
    　前記成形体を緻密化することによって、平均気孔率が９％以下である前記固体電解質層を形成する工程と、
    を備えるリチウムイオン電池の製造方法。     A method for producing a lithium ion battery comprising a solid electrolyte layer disposed between a positive electrode layer and a negative electrode layer,
    Forming a molded body of the solid electrolyte layer containing a first solid electrolyte as a main component and a second solid electrolyte as a subcomponent;
    Forming the solid electrolyte layer having an average porosity of 9% or less by densifying the molded body; and
    A method of manufacturing a lithium ion battery comprising:
  14. 　前記固体電解質層を形成する工程では、前記第２固体電解質の融点以上で前記成形体を焼成することによって前記成形体を緻密化する、
    請求項１３に記載のリチウムイオン電池の製造方法。     In the step of forming the solid electrolyte layer, the molded body is densified by firing the molded body at a melting point of the second solid electrolyte or higher.
    The method for producing a lithium ion battery according to claim 13.
  15. 　前記固体電解質層を形成する工程では、前記成形体を加圧又は加熱して前記第２固体電解質を塑性変形させることによって前記成形体を緻密化する、
    請求項１３に記載のリチウムイオン電池の製造方法。     In the step of forming the solid electrolyte layer, the molded body is densified by pressurizing or heating the molded body to plastically deform the second solid electrolyte.
    The method for producing a lithium ion battery according to claim 13.
  16. 　第１電極と、
    　第２電極と、
    　前記第１電極と前記第２電極との間に配置される固体電解質層と、
    を備え、
    　前記第１電極は、活物質と第１固体電解質と第２固体電解質とを含有し、
    　前記第１電極の平均気孔率は、９％以下である、
    リチウムイオン電池。     A first electrode;
    A second electrode;
    A solid electrolyte layer disposed between the first electrode and the second electrode;
    With
    The first electrode contains an active material, a first solid electrolyte, and a second solid electrolyte,
    The average porosity of the first electrode is 9% or less,
    Lithium ion battery.
  17. 　前記第１電極は、正極層であり、
    　前記正極層における前記第１固体電解質と前記第２固体電解質との合計含有率は、３０ｗｔ％以上であり、
    　前記正極層における前記第２固体電解質の平均含有率は、４ｗｔ％以上２０ｗｔ％以下である、
    請求項１６に記載のリチウムイオン電池。     The first electrode is a positive electrode layer;
    The total content of the first solid electrolyte and the second solid electrolyte in the positive electrode layer is 30 wt% or more,
    The average content of the second solid electrolyte in the positive electrode layer is 4 wt% or more and 20 wt% or less.
    The lithium ion battery according to claim 16.
  18. 　前記第１電極は、負極層であり、
    　前記負極層における前記第１固体電解質と前記第２固体電解質との合計含有率は、３０ｗｔ％以上であり、
    　前記負極層における前記第２固体電解質の平均含有率は、４ｗｔ％以上２０ｗｔ％以下である、
    請求項１６に記載のリチウムイオン電池。     The first electrode is a negative electrode layer;
    The total content of the first solid electrolyte and the second solid electrolyte in the negative electrode layer is 30 wt% or more,
    The average content of the second solid electrolyte in the negative electrode layer is 4 wt% or more and 20 wt% or less.
    The lithium ion battery according to claim 16.
  19. 　第１電極と第２電極との間に配置された固体電解質層を備えるリチウムイオン電池の製造方法であって、
    　活物質と第１固体電解質と第２固体電解質とを含有する前記第１電極の成形体を形成する工程と、
    　前記第１電極の成形体を緻密化することによって、平均気孔率が９％以下である前記第１電極を形成する工程と、
    を備えるリチウムイオン電池の製造方法。     A method for producing a lithium ion battery comprising a solid electrolyte layer disposed between a first electrode and a second electrode,
    Forming a molded body of the first electrode containing an active material, a first solid electrolyte, and a second solid electrolyte;
    Forming the first electrode having an average porosity of 9% or less by densifying the molded body of the first electrode;
    A method of manufacturing a lithium ion battery comprising:
PCT/JP2017/043748 2016-12-27 2017-12-06 Lithium ion cell and method for manufacturing same WO2018123479A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2018558965A JP7009390B2 (en) 2016-12-27 2017-12-06 Lithium-ion battery and its manufacturing method

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2016252792 2016-12-27
JP2016-252792 2016-12-27
JP2017-102754 2017-05-24
JP2017102754 2017-05-24

Publications (1)

Publication Number Publication Date
WO2018123479A1 true WO2018123479A1 (en) 2018-07-05

Family

ID=62710581

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2017/043748 WO2018123479A1 (en) 2016-12-27 2017-12-06 Lithium ion cell and method for manufacturing same

Country Status (2)

Country Link
JP (1) JP7009390B2 (en)
WO (1) WO2018123479A1 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019044903A1 (en) * 2017-08-31 2019-03-07 株式会社村田製作所 Solid electrolyte material, solid electrolyte layer, and all-solid-state battery
KR20200036971A (en) * 2018-09-28 2020-04-08 주식회사 정관 Solid electrolyte, lithium ion battery comprising the same and manufacturing method thereof
WO2020085015A1 (en) * 2018-10-26 2020-04-30 株式会社豊田自動織機 Electrode and solid-state lithium ion secondary battery
WO2020090736A1 (en) * 2018-10-29 2020-05-07 株式会社村田製作所 Solid state battery
JP2020145009A (en) * 2019-03-05 2020-09-10 日本特殊陶業株式会社 Ion conductor and power storage device
WO2020217749A1 (en) * 2019-04-25 2020-10-29 日本碍子株式会社 Lithium secondary battery
CN112242558A (en) * 2019-07-16 2021-01-19 株式会社电装 Lithium ion secondary battery and method for manufacturing same
WO2021038922A1 (en) * 2019-08-23 2021-03-04 日本碍子株式会社 Lithium ion secondary battery
JP2021163579A (en) * 2020-03-31 2021-10-11 本田技研工業株式会社 All-solid battery and manufacturing method therefor
US11322776B2 (en) 2017-08-30 2022-05-03 Murata Manufacturing Co., Ltd. Co-fired all-solid-state battery
WO2022172612A1 (en) 2021-02-12 2022-08-18 パナソニックＩｐマネジメント株式会社 Battery, battery system, and battery manufacturing method
KR102595779B1 (en) * 2023-03-15 2023-10-31 주식회사 베이스 Sintering aid of solid electrolyte for solid-state battery and solid electrolyte comprising the same
US11955596B2 (en) * 2017-08-30 2024-04-09 Murata Manufacturing Co., Ltd. Solid electrolyte and all solid state battery
KR102661427B1 (en) * 2018-10-11 2024-04-25 주식회사 엘지에너지솔루션 A solid electrolyte membrane and a method for manufacturing the sameand a an all solid state lithium secondary batterycomprising the same

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012209256A (en) * 2011-03-15 2012-10-25 Ohara Inc All-solid secondary battery
JP2013140762A (en) * 2012-01-06 2013-07-18 Toyota Central R&D Labs Inc Solid electrolyte, battery including the same, and method for manufacturing the same
WO2013175993A1 (en) * 2012-05-24 2013-11-28 株式会社 村田製作所 All-solid-state cell
WO2014020654A1 (en) * 2012-07-30 2014-02-06 株式会社 日立製作所 All-solid ion secondary cell
WO2015128982A1 (en) * 2014-02-27 2015-09-03 株式会社日立製作所 Lithium secondary cell

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015185290A (en) * 2014-03-22 2015-10-22 株式会社村田製作所 All-solid battery and manufacturing method thereof
JP2016066570A (en) * 2014-09-26 2016-04-28 セイコーエプソン株式会社 Battery, electrode body for battery, and manufacturing method of battery
JP2016154140A (en) * 2015-02-16 2016-08-25 日本碍子株式会社 Method for manufacturing lithium composite oxide sintered plate for lithium secondary battery

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012209256A (en) * 2011-03-15 2012-10-25 Ohara Inc All-solid secondary battery
JP2013140762A (en) * 2012-01-06 2013-07-18 Toyota Central R&D Labs Inc Solid electrolyte, battery including the same, and method for manufacturing the same
WO2013175993A1 (en) * 2012-05-24 2013-11-28 株式会社 村田製作所 All-solid-state cell
WO2014020654A1 (en) * 2012-07-30 2014-02-06 株式会社 日立製作所 All-solid ion secondary cell
WO2015128982A1 (en) * 2014-02-27 2015-09-03 株式会社日立製作所 Lithium secondary cell

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11322776B2 (en) 2017-08-30 2022-05-03 Murata Manufacturing Co., Ltd. Co-fired all-solid-state battery
US11955596B2 (en) * 2017-08-30 2024-04-09 Murata Manufacturing Co., Ltd. Solid electrolyte and all solid state battery
US11942596B2 (en) 2017-08-31 2024-03-26 Murata Manufacturing Co., Ltd. Solid electrolyte material, solid electrolyte layer, and all solid state battery
WO2019044903A1 (en) * 2017-08-31 2019-03-07 株式会社村田製作所 Solid electrolyte material, solid electrolyte layer, and all-solid-state battery
KR20200036971A (en) * 2018-09-28 2020-04-08 주식회사 정관 Solid electrolyte, lithium ion battery comprising the same and manufacturing method thereof
KR102177718B1 (en) * 2018-09-28 2020-11-12 주식회사 정관 Solid electrolyte, lithium ion battery comprising the same and manufacturing method thereof
KR102661427B1 (en) * 2018-10-11 2024-04-25 주식회사 엘지에너지솔루션 A solid electrolyte membrane and a method for manufacturing the sameand a an all solid state lithium secondary batterycomprising the same
WO2020085015A1 (en) * 2018-10-26 2020-04-30 株式会社豊田自動織機 Electrode and solid-state lithium ion secondary battery
JP7156387B2 (en) 2018-10-29 2022-10-19 株式会社村田製作所 solid state battery
WO2020090736A1 (en) * 2018-10-29 2020-05-07 株式会社村田製作所 Solid state battery
JPWO2020090736A1 (en) * 2018-10-29 2021-09-09 株式会社村田製作所 Solid state battery
JP2020145009A (en) * 2019-03-05 2020-09-10 日本特殊陶業株式会社 Ion conductor and power storage device
JP7202218B2 (en) 2019-03-05 2023-01-11 日本特殊陶業株式会社 Ionic conductors and storage devices
JP7193622B2 (en) 2019-04-25 2022-12-20 日本碍子株式会社 lithium secondary battery
JPWO2020217749A1 (en) * 2019-04-25 2021-11-11 日本碍子株式会社 Lithium secondary battery
WO2020217749A1 (en) * 2019-04-25 2020-10-29 日本碍子株式会社 Lithium secondary battery
JP2021015780A (en) * 2019-07-16 2021-02-12 株式会社デンソー Lithium ion secondary battery and manufacturing method thereof
JP7406932B2 (en) 2019-07-16 2023-12-28 株式会社デンソー Manufacturing method of lithium ion secondary battery
CN112242558A (en) * 2019-07-16 2021-01-19 株式会社电装 Lithium ion secondary battery and method for manufacturing same
JP7126028B2 (en) 2019-08-23 2022-08-25 日本碍子株式会社 lithium ion secondary battery
WO2021038922A1 (en) * 2019-08-23 2021-03-04 日本碍子株式会社 Lithium ion secondary battery
TWI771657B (en) * 2019-08-23 2022-07-21 日商日本碍子股份有限公司 Lithium-ion secondary battery
JPWO2021038922A1 (en) * 2019-08-23 2021-03-04
US11817549B2 (en) 2020-03-31 2023-11-14 Honda Motor Co., Ltd. All-solid-state battery and method for manufacturing same
JP2021163579A (en) * 2020-03-31 2021-10-11 本田技研工業株式会社 All-solid battery and manufacturing method therefor
WO2022172612A1 (en) 2021-02-12 2022-08-18 パナソニックＩｐマネジメント株式会社 Battery, battery system, and battery manufacturing method
KR102595779B1 (en) * 2023-03-15 2023-10-31 주식회사 베이스 Sintering aid of solid electrolyte for solid-state battery and solid electrolyte comprising the same

Also Published As

Publication number Publication date
JPWO2018123479A1 (en) 2019-10-31
JP7009390B2 (en) 2022-01-25

Similar Documents

Publication Publication Date Title
WO2018123479A1 (en) Lithium ion cell and method for manufacturing same
JP5910737B2 (en) All solid battery
CN111033859B (en) Solid electrolyte and all-solid battery
WO2018088522A1 (en) Secondary battery
CN111279538B (en) All-solid lithium battery and manufacturing method thereof
JPWO2008143027A1 (en) Lithium ion secondary battery and manufacturing method thereof
KR20190002531A (en) Positive
JP2012099225A (en) All-solid lithium ion secondary battery and method of manufacturing the same
WO2013100000A1 (en) All-solid-state battery, and manufacturing method therefor
JPWO2019093221A1 (en) Rechargeable battery
JP2013243112A (en) All-solid power storage element
KR20190002532A (en) Positive
WO2013100002A1 (en) All-solid-state battery, and manufacturing method therefor
JP6153802B2 (en) Electricity storage element
JP7126518B2 (en) All-solid-state lithium battery and manufacturing method thereof
CN113169372A (en) All-solid-state secondary battery
WO2014050569A1 (en) Positive electrode for lithium ion secondary batteries and lithium ion secondary battery using same
CN115280569A (en) Solid battery
CN113228375A (en) All-solid-state battery
JP2019192609A (en) All-solid lithium battery and method of manufacturing the same
JP2015185290A (en) All-solid battery and manufacturing method thereof
WO2020189599A1 (en) All-solid-state secondary battery
CN115004433A (en) Lithium ion secondary battery
KR20220069620A (en) Composite solid electrolyte for secondary battery, secondary battery including the same, and preparing method thereof
WO2017104363A1 (en) Plate-shaped lithium composite oxide, and method for manufacturing same

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: 17887302

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2018558965

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: 17887302

Country of ref document: EP

Kind code of ref document: A1