Classifications

• • 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
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/362—Composites
  • H01M4/366—Composites as layered products
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
  • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
• • 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
  • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
  • H01M2004/028—Positive electrodes
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present invention relates to electrodes and batteries.
• Patent Document 1 Technology related to electrodes in which an insulating layer is coated and bonded to an active material layer bonded to a current collecting layer has been known (see, for example, Patent Document 1).
• the electrode of the present invention has a current collecting layer, an active material layer, and an insulating layer.
• the active material layer is laminated and bonded to the current collecting layer, and contains an active material.
• the insulating layer is laminated and bonded to the active material layer, and contains an insulating material.
• the insulating material has an average particle diameter of 0.5 ⁇ m or more and 5.0 ⁇ m or less.
• the insulating layer has a porosity of 25% or more and 70% or less. The insulating layer and the active material layer overlap by 0.001% or more and 30% or less along the stacking direction.
• the battery of the present invention has a positive electrode, a negative electrode, and an insulator provided between the positive electrode and the negative electrode. At least one of the positive electrode and the negative electrode is the electrode.
• FIG. 1 is a perspective view showing a battery 1 according to a first embodiment.
• FIG. 2 is a perspective view showing a charging/discharging unit 10 of the battery 1.
• 3 is a cross-sectional view showing the charge/discharge body 10 taken along line 3A-3B in FIG. 2.
• 4 is a cross-sectional view showing the charge/discharge body 10 in region 4 in FIG. 3 .
• FIG. 3 is a side view that illustrates a manufacturing method of the positive electrode 100.
• FIG. 6 is a top view showing a schematic diagram of a state in which a slurry is applied to the positive electrode current collecting layer 110 in FIG. 5 .
• the electrodes in the embodiments of the present invention are described as positive electrodes.
• the electrodes in the embodiments of the present invention also include negative electrodes.
• the battery 1 in the embodiments of the present invention is described as a rectangular prism-shaped battery.
• the battery 1 in the embodiments of the present invention also includes a cylindrical battery.
• FIG. 1 is a perspective view showing a battery 1 of the first embodiment.
• FIG. 2 is a perspective view showing a charging/discharging body 10 of the battery 1.
• FIG. 3 is a cross-sectional view showing the charging/discharging body 10 at 3A-3B in FIG. 2.
• FIG. 4 is a cross-sectional view showing the charging/discharging body 10 in region 4 in FIG. 3.
• Battery 1 is, for example, a lithium ion secondary battery. As shown in Figs. 1 to 4, battery 1 includes a charge/discharge unit 10, an exterior body 50, and an external terminal 60. The main components included in battery 1 are described below.
• the charge/discharge body 10 is charged and discharged.
• the charge/discharge body 10 shown in Figs. 2 and 3 includes a positive electrode 100, a negative electrode 200, a separator 300, and an electrolyte (so-called electrolytic solution).
• the charge/discharge body 10 is formed, for example, by stacking the positive electrode 100, the negative electrode 200, and two separators 300 in the order of the positive electrode 100, the separator 300, the negative electrode 200, and the separator 300, and winding them into a rectangular shape.
• the charge/discharge body 10 is permeated with the electrolyte, particularly the separator 300.
• the charge/discharge body 10 is covered with an insulating sheet with the positive electrode current collector and the negative electrode current collector joined together.
• the positive electrode 100 (electrode) includes a positive electrode current collecting layer 110, a positive electrode active material layer 120, and an insulating layer 130.
• the positive electrode current collecting layer 110 (current collecting layer) is, for example, configured in an elongated shape. That is, the positive electrode current collecting layer 110 is formed in a foil shape. At one end of the positive electrode current collecting layer 110 in the short direction X, a positive electrode current collecting portion 110a is provided along the longitudinal direction Y.
• the positive electrode current collecting layer 110 is, for example, formed of aluminum or an aluminum alloy.
• JIS standard A3003 is used.
• A3003 is a non-heat-treated type, and is an Al-Mn-based alloy.
• the thickness of the positive electrode current collecting layer 110 along the stacking direction Z is, for example, 10 ⁇ m.
• the thickness of the positive electrode current collecting layer 110 is selected, for example, within the range of 5 ⁇ m to 30 ⁇ m.
• the positive electrode active material layer 120 (active material layer) is provided on the positive electrode current collecting layer 110.
• the positive electrode active material layers 120 are laminated and bonded to both sides of the positive electrode current collecting layer 110, facing each other along the lamination direction Z.
• the thickness of the positive electrode active material layer 120 along the lamination direction Z is, for example, 30 ⁇ m or 40 ⁇ m.
• the thickness of the positive electrode active material layer 120 is selected, for example, within the range of 10 ⁇ m to 200 ⁇ m.
• the positive electrode active material layer 120 contains a positive electrode active material 121, a positive electrode binder 122, and a positive electrode conductive additive 123.
• a lithium-containing complex oxide is used for the positive electrode active material 121 (active material).
• the lithium-containing complex oxide is, for example, a metal element such as nickel (Ni), cobalt (Co), or manganese (Mn), and lithium (Li).
• the positive electrode active material 121 is formed in a particulate form.
• the average particle diameter (D50) of the positive electrode active material 121 is, for example, 25 ⁇ m.
• the average particle diameter (D50) of the positive electrode active material 121 is selected, for example, within the range of 1 ⁇ m to 50 ⁇ m.
• the positive electrode binder 122 bonds the positive electrode active material 121 together.
• PVdF polyvinylidene fluoride
• PTFE polytetrafluoroethylene
• PE polyethylene
• SBR styrene butadiene rubber
• nitrocellulose cyanoethyl cellulose
• various latexes acrylic resins, or mixtures thereof are used for the positive electrode binder 122.
• the positive electrode conductive assistant 123 improves the characteristics of the positive electrode 100.
• the positive electrode conductive assistant 123 is mixed with the positive electrode active material 121 and arranged to increase the electrical conductivity between the positive electrode current collecting layer 110 and the positive electrode active material 121. In other words, the positive electrode conductive assistant 123 ensures a conductive path between the positive electrode current collecting layer 110 and the positive electrode active material 121 in the positive electrode 100.
• a carbon-based material is used for the positive electrode conductive assistant 123.
• the carbon-based material is, for example, crystalline carbon, amorphous carbon, or a mixture thereof.
• the crystalline carbon is, for example, artificial graphite, natural graphite, or a mixture thereof.
• the natural graphite is, for example, flake graphite, lump graphite, or earthy graphite.
• the amorphous carbon is, for example, carbon black.
• Carbon black is, for example, acetylene black, ketjen black, channel black, furnace black, lamp black, thermal black, or a mixture thereof.
• the insulating layer 130 is laminated and bonded to the positive electrode active material layer 120.
• the insulating layer 130 has a porosity of 25% or more and 70% or less. The porosity corresponds to the electrolyte retention rate.
• the insulating layer 130 overlaps the positive electrode active material layer 120 by 0.001% or more and 30% or less along the stacking direction Z. The 0.001% or more and 30% or less is a volume ratio.
• the insulating layer 130 has a thickness along the stacking direction Z of 1.0 ⁇ m or more and 10.0 ⁇ m or less. As shown in FIG.
• the region of the insulating layer 130 with a thickness t2 along the stacking direction Z and the region of the positive electrode active material layer 120 with a thickness t1 along the stacking direction Z partially overlap in a region of a thickness t3 along the stacking direction Z.
• the insulating layer 130 suppresses the intrusion of foreign matter into the positive electrode 100.
• the insulating layer 130 contains an insulating material 131, a binder 132, and an additive material 133.
• the insulating material 131 is an inorganic or organic material.
• the insulating material 131 is boehmite or alumina.
• the insulating material 131 is formed in a particulate form.
• the average particle diameter (D50) of the insulating material 131 is 0.5 ⁇ m or more and 5.0 ⁇ m.
• the average particle diameter (D50) of the insulating material 131 is, for example, 1.2 ⁇ m.
• the insulating material 131 has insulating properties. It is preferable that the insulating material 131 has heat resistance.
• the ratio of the insulating material 131 in the insulating layer 130 is, for example, 98%.
• the binder 132 bonds the insulating materials 131 together.
• the binder 132 may be polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), polyethylene (PE), polystyrene, polybutadiene, polyacrylonitrile, polyvinyl fluoride, polypropylene fluoride, polychloroprene fluoride, butyl rubber, nitrile rubber, styrene butadiene rubber (SBR), polysulfide rubber, nitrocellulose, cyanoethyl cellulose, various latexes, acrylic resins, or a mixture of these.
• the binder 132 may be, for example, PVdf.
• the binder 132 has insulating properties.
• the ratio of the binder 132 in the insulating layer 130 may be, for example, 1.9%.
• the additive 133 for example, disperses the insulating material 131 and the binder 132 evenly.
• the additive 133 is, for example, a dispersant.
• the dispersant is, for example, a carboxylic acid compound.
• the ratio of the additive 133 in the insulating layer 130 is, for example, 0.1%.
• the additive 133 is not essential for the insulating layer 130.
• the negative electrode 200 includes a negative electrode current collecting layer 210 and a negative electrode active material layer 220.
• the negative electrode current collecting layer 210 is configured, for example, in an elongated shape. That is, the negative electrode current collecting layer 210 is formed in a foil shape. At one end of the negative electrode current collecting layer 210 in the short side direction X, a negative electrode current collecting portion 210a is provided along the longitudinal direction Y. The negative electrode current collecting portion 210a of the negative electrode current collecting layer 210 faces the positive electrode current collecting portion 110a of the positive electrode current collecting layer 110 in the short side direction X.
• the negative electrode current collecting layer 210 is formed, for example, from copper or a copper alloy.
• the thickness of the negative electrode current collecting layer 210 along the stacking direction Z is, for example, 10 ⁇ m. The thickness of the negative electrode current collecting layer 210 is selected, for example, within the range of 5 ⁇ m to 30 ⁇ m.
• the negative electrode active material layer 220 is provided on the negative electrode current collecting layer 210.
• the negative electrode active material layers 220 are bonded to both sides of the negative electrode current collecting layer 210 and face each other along the stacking direction Z.
• the negative electrode active material layer 220 has a larger width along the short side direction X than the positive electrode active material layer 120.
• both ends of the negative electrode active material layer 220 in the short side direction X are located outside the both ends of the positive electrode active material layer 120 in the short side direction X.
• the thickness of the negative electrode active material layer 220 along the stacking direction Z is, for example, 30 ⁇ m or 40 ⁇ m.
• the thickness of the negative electrode active material layer 220 is selected within the range of, for example, 10 ⁇ m to 200 ⁇ m.
• the negative electrode active material layer 220 contains a negative electrode active material 221 and a negative electrode binder 222.
• the negative electrode active material layer 220 may also contain a negative electrode conductive additive 223.
• the negative electrode active material 221 is, for example, carbon.
• the carbon is, for example, graphite, non-graphitizable carbon (hard carbon), or easily graphitizable carbon (soft carbon).
• the graphite is, for example, natural graphite or artificial graphite.
• the natural graphite is, for example, flake graphite, lump graphite, or earthy graphite.
• the negative electrode active material 221 is formed in a particulate form.
• the average particle size (D50) of the negative electrode active material 221 is, for example, 25 ⁇ m.
• the average particle size (D50) of the negative electrode active material 221 is selected, for example, within the range of 1 ⁇ m to 50 ⁇ m.
• the negative electrode binder 222 bonds the negative electrode active materials 221 together.
• the negative electrode binder 222 is made of the same material as the positive electrode binder 122.
• the negative electrode conductive additive 223 improves the characteristics of the negative electrode 200.
• the negative electrode conductive additive 223 is mixed with the negative electrode active material 221 and arranged to increase the electrical conductivity between the negative electrode current collecting layer 210 and the negative electrode active material 221. In other words, the negative electrode conductive additive 223 ensures a conductive path between the negative electrode current collecting layer 210 and the negative electrode active material 221 in the negative electrode 200.
• the negative electrode 200 may include an insulating layer that covers the negative electrode active material layer 220.
• the insulating layer has heat resistance.
• the insulating layer contains, for example, an inorganic material or an organic material and a binder.
• the inorganic material is, for example, alumina particles.
• the separator 300 (insulator) insulates the positive electrode 100 and the negative electrode 200.
• the insulating layer 130 of the positive electrode 100 faces the negative electrode 200 in the stacking direction Z through the separator 300.
• the separator 300 also holds an electrolyte (so-called electrolytic solution).
• the separator 300 is formed in an elongated shape.
• the separator 300 has a larger width in the short direction X than the negative electrode active material layer 220.
• both ends of the positive electrode active material layer 120 in the short direction X and both ends of the negative electrode active material layer 220 in the short direction X are located within the range along the short direction X of the separator 300.
• the thickness of the separator 300 along the stacking direction Z is, for example, 20 ⁇ m.
• the thickness of the separator 300 is selected, for example, within the range of 5 ⁇ m to 60 ⁇ m.
• the separator 300 is made of a porous material.
• the porous material include polyethylene, polypropylene, polyester, cellulose, and polyamide.
• the separator 300 may be made of a laminate of multiple different porous materials.
• the separator 300 may include an insulating layer.
• the insulating layer has heat resistance.
• the insulating layer contains, for example, an inorganic material or an organic material and a binder.
• the inorganic material is, for example, alumina particles.
• the electrolyte allows lithium ions to flow between the positive electrode 100 and the negative electrode 200.
• the electrolyte is also called an electrolytic solution.
• the electrolyte contains an organic solvent and a lithium salt.
• the electrolyte may also contain additives.
• the organic solvent may be, for example, a carbonate ester such as ethylene carbonate.
• the lithium salt may be, for example, lithium hexafluorophosphate (LiPF 6 ).
• the additive may be, for example, lithium hexafluorophosphate (LiPF 6 ) .
• the exterior body 50 houses the charging/discharging unit 10. As shown in FIG. 1, the exterior body 50 includes a container 51, a lid 52, a liquid injection plug 53, and a split valve 54.
• the container 51 is formed in a rectangular parallelepiped shape.
• the container 51 houses the charging/discharging unit 10.
• the lid 52 is welded to the container 51.
• the lid 52 is provided with a liquid injection hole.
• the liquid injection hole is a hole for injecting an electrolyte (so-called electrolytic solution) into the inside of the battery 1.
• the liquid injection plug 53 is attached to the liquid injection hole of the lid 52.
• the liquid injection plug 53 is inserted into the liquid injection hole and welded after the electrolyte is injected into the inside of the battery 1 through the liquid injection hole.
• the split valve 54 is provided on the lid 52.
• the split valve 54 is formed integrally with the lid 52.
• the split valve 54 splits toward the outside of the battery 1 when the internal pressure of the battery 1 exceeds a
• the external terminal 60 relays the input and output of power between the collector provided inside the battery 1 and an electrical device provided outside the battery 1.
• the electrical device is, for example, a relay or inverter provided in the vehicle.
• the external terminal 60 provided on one battery 1 is electrically connected to the external terminal 60 provided on the other battery 1 via a bus bar or the like, and relays the input and output of power between the one battery 1 and the other battery 1.
• the external terminal 60 includes a positive terminal 61 and a negative terminal 62.
• the positive terminal 61 is electrically connected to the positive electrode collector 110a of the positive electrode collector layer 110 via a positive electrode collector plate.
• the positive terminal 61 is attached to the lid 52 via a positive electrode insulating member.
• the negative terminal 62 is electrically connected to the negative electrode collector 210a of the negative electrode collector layer 210 via a negative electrode collector plate.
• the negative terminal 62 is attached to the lid 52 via a negative insulating member.
• Fig. 5 is a side view that typically illustrates the manufacturing method of the positive electrode 100.
• Fig. 6 is a top view that typically illustrates the state in which the slurry is applied to the positive electrode current collecting layer 110 in Fig. 5.
• the coating process involves coating the positive electrode active material layer slurry 1100 and the insulating layer slurry 1200.
• the positive electrode active material layer slurry 1100 is coated onto the positive electrode current collecting layer 110.
• the insulating layer slurry 1200 is coated onto the positive electrode active material layer slurry 1100.
• the positive electrode active material layer slurry 1100 used in the coating process contains a solvent in addition to the components that make up the positive electrode active material layer 120.
• the components that make up the positive electrode active material layer 120 include a positive electrode active material 121, a positive electrode binder 122, and a positive electrode conductive assistant 123.
• the solvent disperses the components contained in the positive electrode active material layer 120.
• a solvent that is vaporizable at temperatures equal to or higher than room temperature is used.
• the solvent is N-methyl-2-pyrrolidone (NMP).
• the insulating layer slurry 1200 used in the coating process contains a solvent in addition to the materials that make up the insulating layer 130.
• the solvent disperses the insulating material 131 and binder 132 contained in the insulating layer 130.
• a solvent that is vaporizable at temperatures above room temperature is used.
• the solvent is N-methyl-2-pyrrolidone (NMP).
• the manufacturing apparatus 1000 for the positive electrode 100 includes a conveying section 1010, a coating section 1020, a drying section 1030, and a rolling section 1040.
• the conveying unit 1010 conveys the members that constitute the positive electrode 100.
• the conveying unit 1010 includes conveying rollers 1011.
• the conveying section 1010 conveys the positive electrode current collecting layer 110 wound around a first roller (not shown) to the coating section 1020, the drying section 1030, and the rolling section 1040 via conveying rollers 1011 and the like.
• the conveying section 1010 winds the positive electrode current collecting layer 110, to which the positive electrode active material layer 120 and the insulating layer 130 are bonded, around a second roller (not shown).
• the conveying roller 1011 and the first roller in contact with the positive electrode current collecting layer 110 also rotate, conveying the positive electrode current collecting layer 110.
• the conveying direction H of the positive electrode current collecting layer 110 corresponds to the longitudinal direction Y of the positive electrode current collecting layer 110.
• the coating unit 1020 applies slurry to the positive electrode current collecting layer 110 and the like.
• the coating unit 1020 includes a first coating head 1021, a first liquid supply pipe 1022, a second coating head 1023, and a second liquid supply pipe 1024.
• the first coating head 1021 is provided along the conveying direction H of the positive electrode current collecting layer 110, that is, along the short side direction X perpendicular to the longitudinal direction Y of the positive electrode current collecting layer 110.
• the first coating head 1021 has a long opening. The long opening is connected to the first liquid supply pipe 1022.
• the first coating head 1021 is supplied with the positive electrode active material layer slurry 1100 from a tank (not shown) via a pump (not shown) and the first liquid supply pipe 1022.
• the first coating head 1021 faces the conveying roller 1011 via the positive electrode current collecting layer 110.
• the first coating head 1021 applies the positive electrode active material layer slurry 1100 to the positive electrode current collecting layer 110 while the positive electrode current collecting layer 110 is being conveyed.
• the second coating head 1023 is provided along the short direction X of the positive electrode current collecting layer 110, as shown in Figures 5 and 6.
• the second coating head 1023 is aligned with the first coating head 1021 along the conveying direction H of the positive electrode current collecting layer 110.
• the second coating head 1023 is located downstream of the first coating head 1021 in the conveying direction H of the positive electrode current collecting layer 110.
• the second coating head 1023 has a long opening formed therein. The long opening is connected to the second liquid supply pipe 1024.
• the insulating layer slurry 1200 is supplied to the second coating head 1023 from a tank (not shown) via a pump (not shown) and the second liquid supply pipe 1024.
• the second coating head 1023 faces the conveying roller 1011 via the positive electrode current collecting layer 110.
• the second coating head 1023 coats the insulating layer slurry 1200 on the positive electrode active material layer slurry 1100 while the positive electrode current collecting layer 110 is being transported. That is, the insulating layer slurry 1200 is coated so as to cover the positive electrode active material layer slurry 1100.
• the insulating layer slurry 1200 may be coated on the positive electrode current collecting layer 110 so as to extend beyond the end of the positive electrode active material layer slurry 1100 in the short direction X and along the long direction Y of the positive electrode active material layer slurry.
• the drying section 1030 dries the slurry.
• the drying section 1030 is provided downstream of the coating section 1020 in the conveying direction H of the positive electrode current collecting layer 110.
• the drying section 1030 includes a dryer 1031.
• the dryer 1031 is provided along the transport direction H of the positive electrode current collecting layer 110, i.e., the longitudinal direction Y of the positive electrode current collecting layer 110.
• the dryer 1031 dries the positive electrode active material layer slurry 1100 and the insulating layer slurry 1200 while the positive electrode current collecting layer 110 is being transported.
• the dryer 1031 is equipped with multiple heat sources along the transport direction H of the positive electrode current collecting layer 110.
• the dryer 1031 uses the multiple heat sources to dry the positive electrode active material layer slurry 1100 and the insulating layer slurry 1200 under multiple conditions.
• the positive electrode active material layer slurry 1100 forms the positive electrode active material layer 120 by evaporating the solvent.
• the positive electrode active material layer slurry 1100 dries by evaporating the NMP contained in the positive electrode active material layer slurry 1100.
• the thickness of the positive electrode active material layer slurry 1100 decreases along the stacking direction Z.
• the positive electrode active material layer 120 is bonded to the positive electrode current collecting layer 110.
• the insulating layer slurry 1200 forms the insulating layer 130 by evaporating the solvent.
• the insulating layer slurry 1200 dries by evaporating the NMP contained in the insulating layer slurry 1200.
• the thickness of the insulating layer slurry 1200 decreases along the stacking direction Z.
• the insulating layer 130 is bonded to the positive electrode active material layer 120.
• the rolling section 1040 rolls the positive electrode current collecting layer 110, the positive electrode active material layer 120, and the insulating layer 130, which are bonded together.
• the rolling section 1040 is provided downstream of the drying section 1030 in the conveying direction H of the positive electrode current collecting layer 110.
• the rolling section 1040 includes a rolling roller 1041 and a driven roller 1042.
• the rolling roller 1041 is provided along the short side direction X of the positive electrode current collecting layer 110 as shown in FIG. 5.
• the rolling roller 1041 faces the insulating layer 130 of the positive electrode 100.
• the driven roller 1042 is provided along the short side direction X of the positive electrode current collecting layer 110 as shown in FIG. 5.
• the driven roller 1042 faces the rolling roller 1041 across the positive electrode 100.
• the driven roller 1042 faces the positive electrode current collecting layer 110 of the positive electrode 100.
• the rolling section 1040 determines the thickness of the positive electrode active material layer 120 and the insulating layer 130 by the distance between the rolling roller 1041 and the driven roller 1042.
• the configuration described with reference to Figures 5 and 6 is a configuration in which the positive electrode active material layer 120 and the insulating layer 130 are bonded to one side of the positive electrode current collecting layer 110. That is, the method for manufacturing the positive electrode 100 shown in Figures 5 and 6 is a so-called single-sided coating method for manufacturing the positive electrode 100.
• the positive electrode 100 has the positive electrode active material layer 120 and the insulating layer 130 bonded to both sides of the positive electrode current collecting layer 110. That is, the positive electrode 100 shown in Figure 3 is configured by so-called double-sided coating. Therefore, in the method for manufacturing the positive electrode 100, after the configuration described with reference to Figures 5 and 6, the positive electrode active material layer 120 and the insulating layer 130 are bonded to the other side of the positive electrode active material layer 120.
• the insulating layers in conditions 1 and 2 correspond to the insulating layer 130 of the positive electrode 100 of the embodiment.
• the insulating layers in conditions 3 and 4 correspond to the insulating layer of the comparative positive electrode.
• condition 1 the ratio of insulating material 131 in insulating layer 130 was set to 98%. In condition 1, the ratio of binder 132 in insulating layer 130 was set to 1.9%. In condition 1, the ratio of solids in insulating layer slurry 1200 was set to 30%. The solids consisted of insulating material 131, binder 132, and additive 133. In condition 1, the viscosity of insulating layer slurry 1200 was 325 mPa ⁇ s.
• condition 2 the solids ratio in the insulating layer slurry 1200 was set to 15%. In other words, in condition 2, the proportion of solvent in the insulating layer slurry 1200 was increased compared to condition 1. In condition 2, the viscosity of the insulating layer slurry 1200 became 100 mPa ⁇ s.
• condition 3 unlike condition 1, the ratio of insulating material in the insulating layer was set to 99.5%. Also, under condition 3, the ratio of binder in the insulating layer was set to 0.4%. In other words, under condition 3, the ratio of insulating material in the insulating layer was increased and the ratio of binder was decreased compared to condition 1. Under condition 3, the viscosity of the insulating layer slurry was 100 mPa ⁇ s.
• condition 4 set the ratio of insulating material in the insulating layer to 90%. Also, condition 4 set the ratio of binder in the insulating layer to 9.9%. In other words, in condition 4, the ratio of insulating material in the insulating layer was reduced and the ratio of binder was increased compared to condition 1. In condition 4, the viscosity of the insulating layer slurry was 800 mPa ⁇ s or more.
• condition 5 the solids ratio in the insulating layer slurry 1200 was set to 10%. In other words, in condition 5, the proportion of solvent in the insulating layer slurry 1200 was increased compared to conditions 1 and 2. In condition 5, the viscosity of the insulating layer slurry 1200 became 3 mPa ⁇ s.
• the insulating layer 130 under condition 1 was sufficiently bonded to the positive electrode active material layer 120.
• the insulating layer 130 under condition 1 had a very good interface with the positive electrode active material layer 120. In other words, the insulating layer 130 under condition 1 had relatively little overlap with the positive electrode active material layer 120.
• the positive electrode 100 provided with the insulating layer 130 under condition 1 was able to suppress an increase in resistance.
• the insulating layer 130 under condition 2 was sufficiently bonded to the positive electrode active material layer 120.
• the insulating layer 130 under condition 2 had a good interface with the positive electrode active material layer 120. In other words, the insulating layer 130 under condition 2 had relatively little overlap with the positive electrode active material layer 120.
• the positive electrode 100 provided with the insulating layer 130 under condition 2 was able to suppress an increase in resistance.
• the insulating layer 130 under condition 3 could not be sufficiently bonded to the positive electrode active material layer 120. This is because, compared to condition 1, under condition 3, the ratio of insulating material in the insulating layer was increased and the ratio of binder was decreased. If the binder ratio is too low, it is difficult to adhere the insulating layer to the positive electrode active material layer.
• the insulating layer 130 under condition 3 had a good interface with the positive electrode active material layer 120.
• the positive electrode 100 equipped with the insulating layer 130 under condition 3 was able to suppress an increase in resistance.
• the insulating layer 130 under condition 4 was sufficiently bonded to the positive electrode active material layer 120.
• the insulating layer 130 under condition 4 had a very good interface with the positive electrode active material layer 120. That is, the insulating layer 130 under condition 4 had relatively little overlap with the positive electrode active material layer 120.
• the positive electrode 100 equipped with the insulating layer 130 under condition 4 was unable to suppress an increase in resistance. This is because, compared to condition 1, under condition 4 the ratio of insulating material in the insulating layer was reduced and the ratio of binder was increased. The binder does not contribute to the battery reaction.
• the insulating layer 130 of condition 5 was not sufficiently bonded to the positive electrode active material layer 120.
• the insulating layer 130 of condition 5 had a poor interface with the positive electrode active material layer 120.
• the insulating layer 130 of condition 5 overlapped with the positive electrode active material layer 120 relatively frequently. This was because the viscosity of the insulating layer slurry 1200 in condition 5 was very low (3 mPa ⁇ s).
• the positive electrode 100 with the insulating layer 130 of condition 5 was unable to suppress the increase in resistance.
• the positive electrode 100 has an insulating layer 130 (insulating layer).
• the insulating layer 130 is laminated and bonded to the positive electrode active material layer 120 (active material layer) and contains an insulating material 131 having insulating properties.
• the insulating material 131 has an average particle diameter (D50) of 0.5 ⁇ m or more and 5.0 ⁇ m.
• the insulating layer 130 has a porosity of 25% or more and 70% or less.
• the insulating layer 130 and the positive electrode active material layer 120 overlap each other by 0.001% or more and 30% or less along the stacking direction Z. The overlapping of the insulating layer 130 and the positive electrode active material layer 120 is based on the volume ratio.
• the overlapping of the insulating layer 130 that does not contribute to the battery reaction with the positive electrode active material layer 120 that contributes to the battery reaction can be suppressed to a certain level or less.
• the insulating layer 130 can be sufficiently impregnated with the electrolyte, allowing the lithium ions to propagate smoothly.
• a positive electrode 100 can be obtained in which the increase in internal resistance is suppressed.
• a battery 1 can be obtained that includes a positive electrode 100 in which the increase in internal resistance is suppressed.
• the insulating layer 130 and the positive electrode active material layer 120 overlap by 1% or less along the stacking direction Z. With this configuration, the overlap between the insulating layer 130 and the positive electrode active material layer 120 is suppressed to 1% or less, so that a positive electrode 100 can be obtained in which the increase in internal resistance is further suppressed.
• the insulating layer 130 and the positive electrode active material layer 120 overlap by 0.5% or less along the stacking direction Z. With this configuration, the overlap between the insulating layer 130 and the positive electrode active material layer 120 is suppressed to 0.5% or less, so that a positive electrode 100 can be obtained in which the increase in internal resistance is further suppressed.
• the insulating material 131 contains boehmite or alumina. With this configuration, the insulating material 131 can be made of a highly versatile material.
• the insulating layer 130 has a thickness along the stacking direction Z of 1.0 ⁇ m or more and 10.0 ⁇ m or less. With this configuration, the proportion of the insulating layer 130 in the positive electrode 100 can be suppressed to a certain percentage or less. As a result, the energy density of the positive electrode 100 can be maintained at a certain level or more.
• the insulating layer 130 faces the negative electrode 200 in the stacking direction Z via the separator 300 (insulator). With this configuration, the insulation between the positive electrode 100 and the negative electrode 200 can be supplemented by the separator 300.
• the battery of the present invention is not limited to the configuration of the battery described in the embodiment, and can be appropriately configured based on the contents described in the claims.
• the positive electrode active material is not limited to nickel (Ni), cobalt (Co) and manganese (Mn) based materials.
• the positive electrode active material of the present invention may be, for example, Fe (olivine iron) based.
• the negative electrode active material is not limited to carbon-based.
• the negative electrode active material of the present invention may be, for example, silicon-based.
• the battery of the present invention is not limited to a configuration in which the charging/discharging body is sealed by a container and a lid.
• the battery of the present invention can be applied to a configuration in which the charging/discharging body is sealed by a laminate film.
• the battery of the present invention is not limited to a lithium-ion battery.
• the battery of the present invention can be applied to, for example, a nickel-metal hydride battery.
• the battery of the present invention is not limited to a secondary battery.
• the battery of the present invention can be applied to a primary battery.
• the charging/discharging body is not limited to a wound type in which a positive electrode, separator, and negative electrode each formed in a long shape are bundled and wound.
• the charging/discharging body of the battery of the present invention can be a stacked type in which multiple positive electrodes, separators, and negative electrodes each formed in a rectangular shape are stacked alternately.
• the charge/discharge body can be a stacked type in which a single separator formed in a long shape is used, and multiple positive electrodes and multiple negative electrodes formed in a relatively short shape are arranged alternately while facing each other through the separator.
• the separator is folded and stacked, so that the positive electrodes and negative electrodes face each other through the separator.
• the charging/discharging body is not limited to a rectangular prism type.
• the charging/discharging body of the battery of the present invention can be a cylindrical or columnar type.
• the charge/discharge body is not limited to a configuration in which an insulating separator is provided between the positive electrode and the negative electrode.
• the battery of the present invention can be applied to a configuration in which an insulating layer is provided on at least one of the positive electrode and the negative electrode without providing a separator. Such a configuration corresponds to a so-called separatorless configuration.
• the battery of the present invention is not limited to a configuration in which only one charging/discharging element is provided.
• the battery of the present invention can be applied to a configuration in which two or more charging/discharging elements are provided.
• the electrodes (positive and negative electrodes) of the present invention are not limited to a configuration in which the ends of the current collecting layer are joined to the current collecting plate.
• the electrodes of the battery of the present invention can be applied to a type in which an electrode tab protruding outward from the edge of the current collecting layer is joined to the current collecting plate.
• the electrodes (positive and negative electrodes) of the present invention are not limited to a configuration in which an active material layer is bonded to both sides of a current collecting layer.
• the electrodes can be applied to a configuration in which an active material layer is bonded to only one side of a current collecting layer.
• the method for manufacturing electrodes (positive and negative electrodes) of the present invention is not limited to a configuration in which an active material layer and an insulating layer are formed by simultaneously applying and drying an active material layer slurry and an insulating layer slurry.
• the method for manufacturing electrodes (positive and negative electrodes) of the present invention can be applied to a configuration in which an active material layer is first formed by applying and drying an active material layer slurry to a current collecting layer. In such a configuration, an insulating layer is then formed by applying and drying an insulating layer slurry to an active material layer.
• the manufacturing method of the electrodes (positive and negative electrodes) of the present invention is not limited to a configuration in which the first and second coating heads are provided independently.
• the manufacturing method of the electrodes (positive and negative electrodes) of the present invention can be applied to a configuration in which the first and second coating heads are integrated.
• 1 battery 10 Charge/discharge body, 50 Exterior body, 51 container, 52 lid, 53 filling tap, 54 split valve, 60 external terminal, 61 positive electrode terminal, 62 negative electrode terminal, 100 positive electrode (electrode), 110 Positive electrode current collecting layer (current collecting layer), 110a positive electrode current collecting portion, 120 positive electrode active material layer (active material layer), 121 Positive electrode active material (active material), 122 positive electrode binder, 123 Positive electrode conductive assistant, 130 insulating layer, 131 Insulating material, 132 Binder, 133 Additives, 200 negative electrode, 210 negative electrode current collecting layer, 210a negative electrode current collecting part, 220 negative electrode active material layer, 221 negative electrode active material, 222 negative electrode binder, 223 Negative electrode conductive assistant, 300 Separator (insulator), 1000 manufacturing equipment, 1010 conveying unit, 1011 Conveying roller, 1020 Coating section, 1021 first coating head, 1022 first liquid supply pipe, 1023 second coating head, 1024 second liquid delivery tube, 1030 Drying section, 1031 Dryer, 1040 Roll

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• 2024
  • 2024-03-13 WO PCT/JP2024/009797 patent/WO2024224859A1/ja not_active Ceased
  • 2024-03-13 JP JP2025516592A patent/JPWO2024224859A1/ja active Pending
  • 2024-03-13 EP EP24796617.9A patent/EP4704157A1/en active Pending
  • 2024-03-13 CN CN202480004500.4A patent/CN120077486A/zh active Pending

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