WO2014204214A1 - Solution de liant pour une anode, bouillie de matériau actif pour une anode comprenant celle-ci, anode utilisant ladite bouillie de matériau actif et dispositif électrochimique comprenant celle-ci - Google Patents

Solution de liant pour une anode, bouillie de matériau actif pour une anode comprenant celle-ci, anode utilisant ladite bouillie de matériau actif et dispositif électrochimique comprenant celle-ci Download PDF

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WO2014204214A1
WO2014204214A1 PCT/KR2014/005376 KR2014005376W WO2014204214A1 WO 2014204214 A1 WO2014204214 A1 WO 2014204214A1 KR 2014005376 W KR2014005376 W KR 2014005376W WO 2014204214 A1 WO2014204214 A1 WO 2014204214A1
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anode
active material
binder
material slurry
binder solution
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PCT/KR2014/005376
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English (en)
Korean (ko)
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양지혜
김장배
이병배
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주식회사 엘지화학
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Priority to CN201480034381.3A priority Critical patent/CN105308780B/zh
Priority claimed from KR1020140074405A external-priority patent/KR20140147052A/ko
Publication of WO2014204214A1 publication Critical patent/WO2014204214A1/fr
Priority to US14/591,135 priority patent/US9515321B2/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • 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
    • 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
    • H01M2004/027—Negative 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 an anode binder solution, an anode active material slurry comprising the same, an anode using the active material slurry, and an electrochemical device comprising the same, and more particularly, to reduce volume expansion of an anode active material due to occlusion and release of lithium.
  • the present invention relates to an anode binder solution for improving durability of an anode to improve life characteristics of an electrochemical device, an anode active material slurry containing the same, an anode using the active material slurry, and an electrochemical device including the same.
  • the electrochemical device is the area that is receiving the most attention in this respect, and the development of a secondary battery capable of charging and discharging has been the focus of attention, and in recent years in the development of such a battery in order to improve the capacity density and specific energy R & D on the design of electrodes and batteries is underway.
  • lithium secondary batteries developed in the early 1990s have a higher operating voltage and greater energy density than conventional batteries such as Ni-MH, Ni-Cd, and sulfuric acid-lead batteries that use an aqueous electrolyte solution. I am in the spotlight.
  • Such electrochemical devices generally include a cathode, an anode, and a separator interposed between the cathode and the anode.
  • the cathode and the anode is dispersed on the surface of each current collector, the electrode active material, the polymer binder and the electrode active material, and coated with an electrode active material slurry containing a solvent for dissolving the polymer binder to dry the electrode active material layer Form.
  • the volume of the anode active material is increased by occluding and releasing lithium.
  • volume expansion may be further intensified.
  • cracks may be formed while the pore size formed on the surface of the anode active material layer increases, and the formation of the cracks causes the anode. Desorption of the active material layer may occur, thereby lowering the charge / discharge characteristics of the electrochemical device, which in turn lowers the life characteristics of the electrochemical device.
  • the problem to be solved by the present invention by reducing the volume expansion of the anode active material due to the occlusion and release of lithium due to the progress of the cycle of the electrochemical device, improve the durability of the anode active material layer to improve the life characteristics of the electrochemical device
  • Anode binder solution for improving the coating stability of the anode active material layer by further maintaining excellent dispersibility of the anode active material slurry, anode active material slurry comprising the same, anode using the active material slurry and electrochemical comprising the same It is to provide an element.
  • a thermal crosslinkable polymer binder crosslinked by heat; And a solvent for dissolving the thermally crosslinkable polymer binder.
  • a binder solution for an anode having a hydrogen ion concentration of pH 2.5 to pH 4.5, preferably pH 3.0 to pH 3.5 is provided.
  • the thermal crosslinkable polymer binder may include a carboxy group as a functional group.
  • the thermally crosslinkable polymer binder including a carboxyl group as a functional group may be polyacrylic acid.
  • the solvent may be acetone, tetra hydrofuran, methylene chloride, chloroform, dimethylform amide, N-methyl-2-pyrrolidone (N). -methyl-2-pyrrolidone, NMP), cyclohexane and any one selected from the group consisting of water or a mixture of two or more thereof.
  • anode binder solution may further include an aqueous binder.
  • the weight ratio of the thermally crosslinkable polymer binder and the aqueous binder may be 2: 8 to 5: 5, preferably 2: 8 to 4: 6.
  • the aqueous binder may include styrene butadiene rubber, carboxymethyl cellulose, polytetrafluoroethylene, polyethylene, polypropylene, ethylene propylene copolymer, polybutadiene, butyl rubber, fluorine rubber, polyethylene oxide, polyvinylpyrrolidone , Polyepichlorohydrin, polyphosphagen, polyacrylonitrile, polystyrene, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl It may be any one selected from the group consisting of alcohol and hydroxypropyl cellulose or a mixture of two or more thereof.
  • the binder solution for the anode And an anode active material dispersed in the anode binder solution, wherein the anode binder solution is provided with an anode active material slurry, wherein the anode binder solution of the present invention is described above.
  • the hydrogen ion concentration of the anode active material slurry may be pH 2.5 to pH 4.5, preferably pH 3.0 to pH 3.5.
  • the solid content of the anode active material slurry may be 43 to 50% by weight of the active material slurry for the anode.
  • the anode active material may include lithium metal, a carbon material, a metal compound, a metal oxide, or a mixture thereof.
  • the metal compound is Si, Ge, Sn, Pb, P, Sb, Bi, Al, Ga, In, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ag, Mg, Sr, and Ba It may be any one selected from the group consisting of or a mixture of two or more thereof.
  • the metal oxide may be any one selected from the group consisting of silicon oxide, tin oxide, titanium oxide, and lithium vanadium oxide, or a mixture of two or more thereof.
  • the current collector On the other hand, according to another aspect of the invention, the current collector; And an anode active material layer formed on one surface or both surfaces of the current collector, and formed of a result of the drying step of the active material slurry for the anode of the present invention described above.
  • the thermal crosslinkable polymer binder can be crosslinked with each other to form a crosslinked polymer network.
  • the drying step to remove the solvent through the first drying at a temperature of 120 to 140 °C, may be to form the cross-linked polymer network through the secondary drying at a temperature of 140 to 160 °C in a vacuum state. .
  • the current collector And an anode active material layer formed on one or both surfaces of the current collector, wherein the anode active material layer comprises an anode active material and a polymer binder, and the polymer binder is a heat crosslinkable polymer that is crosslinked by heat.
  • the thermally crosslinkable polymer binder may be polyacrylic acid
  • the aqueous binder may be styrene butadiene rubber.
  • the anode in the electrochemical device comprising a cathode, an anode, a separator interposed between the cathode and the anode and the non-aqueous electrolyte, the anode is the electrochemical of the above-described anode of the present invention An element is provided.
  • the electrochemical device may be a lithium secondary battery.
  • the coating stability of the anode active material layer may be improved by maintaining the dispersibility of the active material slurry for the anode.
  • 1 is a graph showing viscoelastic properties of an active material slurry for anode according to Examples and Comparative Examples of the present invention.
  • Figure 2 is a SEM photograph showing the surface of the anode prepared according to an embodiment of the present invention.
  • Figure 3 is an anode prepared according to an embodiment of the present invention, a SEM photograph showing the surface after 70 cycles.
  • Figure 4 is a SEM photograph showing the surface of the anode prepared according to a comparative example of the present invention.
  • FIG. 6 is a graph comparing capacity retention rates for 70 cycles of coin-shaped half cells prepared according to one embodiment and one comparative example of the present invention.
  • the binder solution for the anode according to the present invention comprises a thermal crosslinkable polymer binder crosslinked by heat; And a solvent for dissolving the thermally crosslinkable polymer binder, wherein the hydrogen ion concentration is pH 2.5 to pH 4.5, preferably pH 3.0 to pH 3.5.
  • the anode active material slurry according to the present invention is an anode binder solution; And an anode active material dispersed in the anode binder solution; wherein the anode binder solution is an anode binder solution according to the present invention.
  • the hydrogen ion concentration of the anode active material slurry may be pH 2.5 to pH 4.5, preferably pH 3.0 to pH 3.5.
  • the anode active material used to be applied to the anode of the electrochemical device generates volume expansion upon occlusion and release of lithium.
  • volume expansion may be further intensified.
  • cracks may be formed while the pore size formed on the surface of the anode active material layer increases, and the formation of such cracks causes desorption of the anode active material layer.
  • the conductivity between the active material and the current collector is lowered, and the conductivity between the anode active material is lowered, thereby lowering the charge / discharge characteristics of the electrochemical device, which in turn lowers the life characteristics of the electrochemical device.
  • a heat crosslinkable polymer binder crosslinked by heat is used as the polymer binder used in the production of the anode.
  • the thermally crosslinkable polymer binder When the anode active material slurry including the thermally crosslinkable polymer binder is applied to at least one surface of a current collector and then dried, the thermally crosslinkable polymer binder is crosslinked with each other to form a crosslinked polymer network, and the crosslinked polymer network is an active material layer.
  • the binder solution and the active material slurry dispersibility may be expressed by expressing a liquid behavior having a very high viscosity compared to elasticity. Maintained to be excellent to improve the coating stability of the anode active material layer.
  • the solid amount of the active material slurry for the anode may be 43 to 50% by weight of the active material slurry for the anode.
  • an appropriate viscosity of the active material slurry for the anode may be maintained and uniformly coated on the current collector, and the amount of moisture to be dried is not excessive so that the drying time can be properly maintained.
  • the thermally crosslinkable polymer binder may be one containing a carboxyl group as a functional group. Since the carboxyl group is crosslinked by heat, it forms anhydrous carboxylic anhydride groups other than hydrogen bonds between molecules, so that the linear polymer chain may be partially changed into a crosslinked polymer network to mitigate volume expansion of the anode active material.
  • the thermally crosslinkable polymer binder including a carboxyl group as a functional group may be polyacrylic acid.
  • the weight average molecular weight of the polyacrylic acid may be 400,000 to 800,000, but is not limited thereto.
  • the anode binder solution may further include an aqueous binder.
  • the weight ratio of the thermal crosslinkable polymer binder and the aqueous binder may be 2: 8 to 5: 5, preferably 2: 8 to 4: 6.
  • the weight ratio of the aqueous binder exceeds the upper limit of the numerical range, the mechanical properties of the electrode active material layer may be improved, but there is a concern that the resistance of the electrode active material layer may be increased.
  • the weight ratio of the thermally crosslinkable polymer binder exceeds the upper limit of the numerical range, the mechanical properties of the electrode active material layer may decrease, and the stability of the electrode active material slurry may decrease. Therefore, when the weight ratio is satisfied, an appropriate amount of the crosslinked polymer network is formed, thereby alleviating the volume expansion of the anode active material layer.
  • the water-based binder refers to a water-soluble or water-dispersible binder polymer, styrene butadiene rubber, carboxymethyl cellulose, polytetrafluoroethylene, polyethylene, polypropylene, ethylene propylene copolymer, polybutadiene, butyl rubber , Fluororubber, polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphagen, polyacrylonitrile, polystyrene, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin , Acrylic resin, phenol resin, epoxy resin, polyvinyl alcohol and hydroxypropyl cellulose may be any one selected from the group consisting of or a mixture of two or more thereof.
  • anode active material may be a conventional anode active material that can be used in the anode of the conventional electrochemical device, in particular may include lithium metal, carbon material, metal compounds, metal oxides or mixtures thereof. have.
  • a lithium adsorption material such as carbon, petroleum coke, activated carbon, graphite, or other carbons may be used.
  • the metal compound may be Si, Ge, Sn, Pb, P, Sb, Bi, Al, Ga, In, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ag, Mg, Sr, and Ba. It may be any one selected from the group consisting of or a mixture of two or more thereof.
  • the metal oxide may be any one selected from the group consisting of silicon oxide, tin oxide, titanium oxide, and lithium vanadium oxide, or a mixture of two or more thereof.
  • the solvent may be acetone, tetra hydrofuran, methylene chloride, chloroform, dimethylform amide, N-methyl-2-pyrrolidone (N). -methyl-2-pyrrolidone, NMP), cyclohexane, and any one selected from the group consisting of water or a mixture of two or more thereof, but is not limited thereto.
  • the solvent may be removed in the manufacturing process of the electrochemical device, since the solvent may cause various side reactions when remaining in the finally manufactured electrochemical device.
  • the current collector On the other hand, according to an aspect of the present invention, the current collector; And an anode active material layer formed on one surface or both surfaces of the current collector, and formed of a result of the drying step of the active material slurry for the anode of the present invention described above.
  • non-limiting examples of the current collector include a foil made by copper, gold, nickel or a copper alloy or a combination thereof.
  • the drying step the solvent is removed, the thermal crosslinkable polymer binder can be cross-linked with each other to form a crosslinked polymer network, wherein the drying step, the first drying at a temperature of 120 to 140 °C The solvent may be removed, and the crosslinked polymer network may be formed through secondary drying at a temperature of 140 to 160 ° C. in a vacuum state.
  • the current collector And an anode active material layer formed on one or both surfaces of the current collector, wherein the anode active material layer comprises an anode active material and a polymer binder, and the polymer binder is a heat crosslinkable polymer that is crosslinked by heat.
  • the weight ratio of the thermally crosslinkable polymer binder and the aqueous binder if the weight ratio of the aqueous binder exceeds the upper limit of the numerical range, the mechanical properties of the electrode active material layer can be improved, but the resistance of the electrode active material layer There is a fear of increasing.
  • the weight ratio of the thermally crosslinkable polymer binder exceeds the upper limit of the numerical range, the mechanical properties of the electrode active material layer may decrease, and the stability of the electrode active material slurry may decrease. Therefore, when the weight ratio is satisfied, an appropriate amount of the crosslinked polymer network is formed, thereby alleviating the volume expansion of the anode active material layer.
  • the thermally crosslinkable polymer binder may be polyacrylic acid
  • the aqueous binder may be styrene butadiene rubber.
  • the anode in the electrochemical device comprising a cathode, an anode, a separator interposed between the cathode and the anode and the non-aqueous electrolyte, is characterized in that the anode of the present invention described above An electrochemical device is provided.
  • the electrochemical device of the present invention includes all devices that perform an electrochemical reaction, and specific examples include capacitors such as all kinds of primary, secondary, fuel, solar, or supercapacitor devices.
  • capacitors such as all kinds of primary, secondary, fuel, solar, or supercapacitor devices.
  • a lithium secondary battery including a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery or a lithium ion polymer secondary battery among the secondary batteries is preferable.
  • the electrochemical device according to the present invention may perform stacking, lamination, folding, and stacking / folding processes of the separator and the electrode.
  • the external shape of the electrochemical device is not particularly limited, but may be cylindrical, square, pouch or coin type using a can.
  • the cathode to be applied to the electrochemical device according to the present invention is not particularly limited, and the cathode active material may be manufactured in a form bound to the current collector according to conventional methods known in the art.
  • Non-limiting examples of the cathode active material may be a conventional cathode active material that can be used for the cathode of the conventional electrochemical device, in particular lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron oxide or a combination of these lithium composites Oxides can be used.
  • non-limiting examples of the cathode current collector is a foil produced by aluminum, nickel or a combination thereof.
  • the separator used in the present invention can be used as long as it is a porous substrate commonly used in the art, for example, a polyolefin-based porous membrane (membrane) or non-woven fabric may be used, but is not particularly limited thereto.
  • polyolefin-based porous membrane examples include polyethylene, polypropylene, polybutylene, polypentene, such as high density polyethylene, linear low density polyethylene, low density polyethylene, ultra high molecular weight polyethylene, respectively, or a mixture thereof
  • polyolefin-based polymers such as polyethylene, polypropylene, polybutylene, polypentene, such as high density polyethylene, linear low density polyethylene, low density polyethylene, ultra high molecular weight polyethylene, respectively, or a mixture thereof
  • polyethylene such as polyethylene, polypropylene, polybutylene, polypentene, such as high density polyethylene, linear low density polyethylene, low density polyethylene, ultra high molecular weight polyethylene, respectively, or a mixture thereof
  • polypentene such as high density polyethylene, linear low density polyethylene, low density polyethylene, ultra high molecular weight polyethylene, respectively, or a mixture thereof
  • the nonwoven fabric may be, for example, polyethylene terephthalate, polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, or polycarbonate. ), Polyimide, polyetheretherketone, polyethersulfone, polyphenyleneoxide, polyphenylenesulfide, polyethylenenaphthalene, etc., alone or separately
  • the nonwoven fabric formed from the polymer which mixed these is mentioned.
  • the structure of the nonwoven can be a spunbond nonwoven or melt blown nonwoven composed of long fibers.
  • the thickness of the porous substrate is not particularly limited, but may be 5 ⁇ m to 50 ⁇ m, and the pore size and pore present in the porous substrate are also not particularly limited, but may be 0.01 ⁇ m to 50 ⁇ m and 10 to 95%, respectively.
  • At least one surface of the porous substrate may further include a porous coating layer including inorganic particles and a polymer binder.
  • the inorganic particles are not particularly limited as long as they are electrochemically stable. That is, the inorganic particles that can be used in the present invention are not particularly limited as long as the oxidation and / or reduction reactions do not occur in the operating voltage range (for example, 0 to 5 V on the basis of Li / Li + ) of the applied electrochemical device.
  • the ionic conductivity of the electrolyte may be improved by contributing to an increase in the dissociation degree of the electrolyte salt, such as lithium salt, in the liquid electrolyte.
  • the polymer binder may be polyvinylidene fluoride-hexafluorofluoropropylene (polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP)), polyvinylidene fluoride-chlorotrifluorofluoroethylene (polyvinylidene fluoride-co -chlorotrifluoroethylene, polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polybutylacrylate, polyacrylonitrile, polyvinyl Pyrrolidone (polyvinylpyrrolidone), polyvinylacetate, ethylene vinyl-co-vinyl acetate, polyethylene, polyethylene oxide, polyarylate, cellulose acetate ( cellulose acetate), cellulose acetate butyrate, Cellulose acetate propionate, cyanoethylpullulan, cyanoethylpolyvinylalcohol
  • the polymer binder is coated on a part or the entire surface of the inorganic particles, and the inorganic particles are connected and fixed to each other by the polymer binder in close contact with each other, and an empty space existing between the inorganic particles. Due to the pores are preferably formed. That is, the inorganic particles of the porous coating layer are in close contact with each other, and the empty space generated when the inorganic particles are in close contact with the pores of the porous coating layer.
  • the size of the void space present between the inorganic particles is preferably equal to or smaller than the average particle diameter of the inorganic particles.
  • the electrolyte salt contained in the nonaqueous electrolyte solution that can be used in the present invention is a lithium salt.
  • the lithium salt may be used without limitation those conventionally used in the lithium secondary battery electrolyte.
  • organic solvent included in the nonaqueous electrolyte described above those conventionally used in the lithium secondary battery electrolyte may be used without limitation, and for example, ethers, esters, amides, linear carbonates, and cyclic carbonates may be used alone or in combination of two or more. It can be mixed and used.
  • carbonate compounds which are typically cyclic carbonates, linear carbonates, or mixtures thereof may be included.
  • cyclic carbonate compound examples include ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate, vinylene carbonate, vinylethylene carbonate and any one selected from the group consisting of halides thereof or mixtures of two or more thereof.
  • halides include, for example, fluoroethylene carbonate (FEC), but are not limited thereto.
  • linear carbonate compounds may be any one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, ethylmethyl carbonate (EMC), methylpropyl carbonate and ethylpropyl carbonate. Mixtures of two or more of them may be representatively used, but are not limited thereto.
  • ethylene carbonate and propylene carbonate which are cyclic carbonates among the carbonate-based organic solvents, are high viscosity organic solvents and have a high dielectric constant, so that they can dissociate lithium salts in the electrolyte better, and cyclic carbonates such as dimethyl carbonate and diethyl carbonate.
  • cyclic carbonates such as dimethyl carbonate and diethyl carbonate.
  • any one selected from the group consisting of dimethyl ether, diethyl ether, dipropyl ether, methylethyl ether, methylpropyl ether, and ethylpropyl ether, or a mixture of two or more thereof may be used. It is not limited to this.
  • esters in the organic solvent include methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ⁇ -butyrolactone, ⁇ -valerolactone, ⁇ -caprolactone, ⁇ -valerolactone and One or a mixture of two or more selected from the group consisting of ⁇ -caprolactone may be used, but is not limited thereto.
  • the injection of the nonaqueous electrolyte may be performed at an appropriate step in the manufacturing process of the electrochemical device, depending on the manufacturing process and the required physical properties of the final product. That is, it may be applied before the electrochemical device assembly or the final step of the electrochemical device assembly.
  • anode active material a mixture of KSC1064 (SiO: C, Shin-Etsu Co., Ltd.) and MAG-V2 (artificial graphite / natural graphite mixture, Hitachi Chemical Co., Ltd.) (weight ratio of KSC1064 and MAG-V2 is 1: 2) was used.
  • binder polyacrylic acid (Sigma Aldrich) having a weight average molecular weight of about 450,000 and a styrene butadiene rubber as an aqueous binder were used, and carbon nanotubes were mixed as a conductive material, and an anode active material slurry having a pH of 3.3 was used.
  • the anode active material, the binder and the conductive material were mixed in a weight ratio of 90: 7: 3, the binder was adjusted so that the weight ratio of styrene butadiene rubber and polyacrylic acid is 7: 3.
  • An anode active material slurry was prepared in the same manner as in Example 1 except that the hydrogen ion concentration of the anode active material slurry was pH 7.3.
  • An anode active material slurry was prepared in the same manner as in Example 1 except that carboxymethyl cellulose was used as the polymer binder.
  • 1 is a graph showing viscoelastic properties of an active material slurry for anode according to Examples and Comparative Examples of the present invention.
  • Example 1-1 the elasticity of the solid phase is stronger than that of the viscosity, whereas in Example 1-1, the viscosity is low according to the shear rate and the viscosity is higher than the elasticity. Since it exhibits very high liquid phase behavior, it can be said that the dispersibility of Example 1-1 is the best.
  • the anode active material slurry prepared in Example 1-1 was coated on a copper (Cu) foil current collector in a conventional manner to prepare an anode.
  • a coin-type half cell was prepared using an electrode assembly made of a polyethylene porous membrane interposed between the anode and the lithium metal.
  • a coin-type half cell was prepared in the same manner as in Example 1-2 except for using the anode active material slurry prepared in Comparative Example 1-1 as the anode active material slurry.
  • a coin-type half cell was prepared in the same manner as in Example 1-2 except for using the anode active material slurry prepared in Comparative Example 2-1 as the anode active material slurry.
  • the capacity was measured under continuous charge and discharge conditions. Then, the surface of the anode was observed through SEM to confirm the degree of degradation of the anode before and after the cycle.
  • FIGS. 4 and 5 show the initial anode prepared according to Comparative Example 2-2 and 70 respectively. The anode surface after the cycle is shown.
  • Comparative Example 2-2 it was confirmed that the crack length is long during the course of the cycle due to small pores or small cracks already formed before the cycle.
  • Example 1-2 the size of the pores or cracks is formed smaller than that of Comparative Example 2-2, and the change in the size of the cracks was significantly smaller during the cycle, and rather the size of the pores was smaller. I could confirm it.
  • Example 2-2 the stress due to the volume expansion of the anode active material with the progress of the cycle is solved in the direction of increasing the size of the crack
  • Example 1-2 the stress in the direction of decreasing the pore size It can be judged to solve the problem.
  • Figure 6 shows the capacity retention rate according to the cycle progress of the coin-type half cell prepared in Example 1-2 and Comparative Example 2-2. Referring to FIG. 6, after 70 cycles, the capacity retention rate of 94.2% was shown in the case of the example, but the capacity retention rate of the comparative example was 70.2%.

Abstract

La présente invention porte sur une solution de liant pour une anode ayant une concentration d'ions d'hydrogène de pH 2,5 à pH 4,5, une bouillie de matériau actif pour une anode comprenant celle-ci, une anode utilisant la bouillie de matériau actif et un dispositif électrochimique comprenant l'anode, la solution de liant pour une anode comprenant : un liant de polymère à réticulation thermique qui est réticulé par chaleur ; et un solvant pour dissoudre le liant de polymère à réticulation thermique. Selon un exemple de la présente invention, par atténuation de l'expansion volumétrique d'un matériau actif d'anode en raison de l'absorption et de la libération de lithium qui se produisent lorsqu'un dispositif électrochimique parcourt ses cycles, la durabilité d'une couche d'un matériau actif d'anode est améliorée pour ainsi permettre à la caractéristique de durée de vie du dispositif électrochimique d'être améliorée, et la dispersibilité de bouillie de matériau actif pour une anode reste exceptionnelle pour ainsi permettre à la stabilité d'enrobage du matériau actif d'anode d'être améliorée.
PCT/KR2014/005376 2013-06-18 2014-06-18 Solution de liant pour une anode, bouillie de matériau actif pour une anode comprenant celle-ci, anode utilisant ladite bouillie de matériau actif et dispositif électrochimique comprenant celle-ci WO2014204214A1 (fr)

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Application Number Priority Date Filing Date Title
CN201480034381.3A CN105308780B (zh) 2013-06-18 2014-06-18 一种负极以及含有该负极的电化学器件
US14/591,135 US9515321B2 (en) 2013-06-18 2015-01-07 Binder solution for anode, active material slurry for anode comprising the binder solution, anode using the slurry and electrochemical device comprising the anode

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KR20130069920 2013-06-18
KR10-2013-0069920 2013-06-18
KR10-2014-0074405 2014-06-18
KR1020140074405A KR20140147052A (ko) 2013-06-18 2014-06-18 애노드용 바인더 용액, 그를 포함하는 애노드용 활물질 슬러리, 그 활물질 슬러리를 이용한 애노드 및 이를 포함하는 전기화학소자

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US14/591,135 Continuation US9515321B2 (en) 2013-06-18 2015-01-07 Binder solution for anode, active material slurry for anode comprising the binder solution, anode using the slurry and electrochemical device comprising the anode

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116093331A (zh) * 2023-04-06 2023-05-09 宁德新能源科技有限公司 二次电池和电子装置
CN116111100A (zh) * 2023-04-12 2023-05-12 深圳好电科技有限公司 锂离子电池负极材料及其制备方法、锂离子电池

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20020018393A (ko) * 2000-09-01 2002-03-08 김순택 수명특성이 개선된 리튬 설퍼 2차 전지
KR20040009328A (ko) * 2002-07-23 2004-01-31 삼성에스디아이 주식회사 가교 바인더를 포함하는 리튬 설퍼 전지용 극판 및 이극판을 포함하는 리튬 설퍼 전지
KR20060110235A (ko) * 2005-04-19 2006-10-24 주식회사 엘지화학 가교 고분자의 도입에 의해 안전성이 향상된 전극 및 이를포함하는 전기 화학 소자
KR20090119895A (ko) * 2007-03-16 2009-11-20 세키스이가가쿠 고교가부시키가이샤 전극 바인더, 전극, 막-전극 접합체 및 고체 고분자형 연료 전지
KR20110060094A (ko) * 2009-11-30 2011-06-08 현대자동차주식회사 고분자 전해질 연료전지용 전극 및 이를 이용한 막-전극 어셈블리 제조 방법

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20020018393A (ko) * 2000-09-01 2002-03-08 김순택 수명특성이 개선된 리튬 설퍼 2차 전지
KR20040009328A (ko) * 2002-07-23 2004-01-31 삼성에스디아이 주식회사 가교 바인더를 포함하는 리튬 설퍼 전지용 극판 및 이극판을 포함하는 리튬 설퍼 전지
KR20060110235A (ko) * 2005-04-19 2006-10-24 주식회사 엘지화학 가교 고분자의 도입에 의해 안전성이 향상된 전극 및 이를포함하는 전기 화학 소자
KR20090119895A (ko) * 2007-03-16 2009-11-20 세키스이가가쿠 고교가부시키가이샤 전극 바인더, 전극, 막-전극 접합체 및 고체 고분자형 연료 전지
KR20110060094A (ko) * 2009-11-30 2011-06-08 현대자동차주식회사 고분자 전해질 연료전지용 전극 및 이를 이용한 막-전극 어셈블리 제조 방법

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116093331A (zh) * 2023-04-06 2023-05-09 宁德新能源科技有限公司 二次电池和电子装置
CN116111100A (zh) * 2023-04-12 2023-05-12 深圳好电科技有限公司 锂离子电池负极材料及其制备方法、锂离子电池
CN116111100B (zh) * 2023-04-12 2023-09-19 深圳好电科技有限公司 锂离子电池负极材料及其制备方法、锂离子电池

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