WO2013073400A1 - Positive electrode for lithium ion secondary batteries and lithium ion secondary battery using same - Google Patents

Positive electrode for lithium ion secondary batteries and lithium ion secondary battery using same Download PDF

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Publication number
WO2013073400A1
WO2013073400A1 PCT/JP2012/078629 JP2012078629W WO2013073400A1 WO 2013073400 A1 WO2013073400 A1 WO 2013073400A1 JP 2012078629 W JP2012078629 W JP 2012078629W WO 2013073400 A1 WO2013073400 A1 WO 2013073400A1
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Prior art keywords
aluminum silicate
positive electrode
lithium ion
ion secondary
secondary battery
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PCT/JP2012/078629
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French (fr)
Japanese (ja)
Inventor
紘揮 三國
潔 川合
克倫 古田土
裕史 中嶋
片山　秀昭
児島　克典
愛知　且英
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新神戸電機株式会社
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Publication of WO2013073400A1 publication Critical patent/WO2013073400A1/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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—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
    • 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 a positive electrode for a lithium ion secondary battery and a lithium ion secondary battery using the same.
  • Lithium-ion secondary batteries are lighter and have higher input / output characteristics than other secondary batteries such as nickel metal hydride batteries and lead-acid batteries. It is attracting attention as an output power source.
  • impurities for example, magnetic impurities such as Fe, Ni, Cu, etc.
  • impurities for example, magnetic impurities such as Fe, Ni, Cu, etc.
  • the operating temperature of lithium ion secondary batteries may be 40 ° C to 80 ° C, such as in the car in summer.
  • the metal in the Li-containing metal oxide constituting the positive electrode is eluted from the positive electrode, and the characteristics of the battery are deteriorated. For this reason, examination of the trap of impurities and examination of the stabilization of the positive electrode have been made (for example, refer to Patent Document 1).
  • a lithium compound containing Fe or Mn as a metal element is used as a positive electrode active material, and the effective pore diameter is larger than the ion radius of the metal element and 0.5 nm (5 mm) or less.
  • Patent Document 2 a lithium compound containing Fe or Mn as a metal element is used as a positive electrode active material, and the effective pore diameter is larger than the ion radius of the metal element and 0.5 nm (5 mm) or less.
  • an object of the present invention is to provide a positive electrode for a lithium ion secondary battery excellent in metal ion adsorption and metal ion selectivity and a lithium ion secondary battery using the positive electrode.
  • ⁇ 4> The positive electrode for a lithium ion secondary battery according to any one of ⁇ 1> to ⁇ 3>, wherein the element molar ratio Si / Al of the aluminum silicate is 0.4 or more and 0.6 or less. .
  • the aluminum silicate has an area ratio (peak B / peak A) between peak A around -78 ppm and peak B around -85 ppm in the range of 2.0 to 9.0.
  • the positive electrode for a lithium ion secondary battery according to any one of the above items ⁇ 3> to ⁇ 5>.
  • ⁇ 7> The positive electrode for a lithium ion secondary battery according to any one of ⁇ 1> to ⁇ 6>, wherein the aluminum silicate has a BET specific surface area of 250 m 2 / g or more.
  • ⁇ 8> The positive electrode for a lithium ion secondary battery according to any one of ⁇ 1> to ⁇ 7>, wherein the aluminum silicate is provided by a dispersion containing the aluminum silicate.
  • the present invention it is possible to provide a positive electrode for a lithium ion secondary battery excellent in metal ion adsorption and metal ion selectivity and a lithium ion secondary battery using the same.
  • FIG. 2 is a 27Al-NMR spectrum of an aluminum silicate according to Example 1 and Example 2.
  • FIG. 2 is a 29Si-NMR spectrum of aluminum silicate according to Example 1 and Example 2.
  • FIG. 2 is a transmission electron microscope (TEM) photograph of aluminum silicate according to Example 1.
  • FIG. 2 is a transmission electron microscope (TEM) photograph of aluminum silicate according to Example 2.
  • FIG. It is a figure which shows typically what is called tubular imogolite which is an example of this embodiment.
  • 2 is a powder X-ray diffraction spectrum of aluminum silicate according to Example 1 and Example 2.
  • the term “process” is not limited to an independent process, and is included in the term if the intended action of the process is achieved even when it cannot be clearly distinguished from other processes. .
  • a numerical range indicated using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively.
  • the amount of each component in the composition is the sum of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. Means quantity.
  • the positive electrode for a lithium ion secondary battery of the present invention is provided with an aluminum silicate having an Si / Al element molar ratio Si / Al of 0.3 or more and less than 1.0 on the surface.
  • An aluminum silicate having an element molar ratio Si / Al of 0.3 to less than 1.0 (hereinafter sometimes referred to as “specific aluminum silicate”) has many metal ions per unit mass. And has a feature of highly selectively adsorbing metal ions with a high specific surface area.
  • Specified aluminum silicate is an oxide salt of Si and Al and has different valences, so there are many OH groups, and this has ion exchange ability. Therefore, it has a feature of having many metal ion adsorption sites per unit mass and highly selectively adsorbing metal ions with a high specific surface area.
  • the specific aluminum silicate has a specific property of adsorbing unnecessary metal ions even though it hardly adsorbs lithium ions essential for charging and discharging of a lithium ion battery.
  • unnecessary metal ions refer to nickel ions other than lithium ions, manganese ions, copper ions, and the like. These unnecessary metal ions are derived from impurity ions present in the constituent materials of the battery and metal ions eluted from the positive electrode at a high temperature.
  • the specific aluminum silicate is an inorganic oxide, it has excellent thermal stability and stability in a solvent. For this reason, it can exist stably even during charging and discharging.
  • impurity ions are ionized at the positive electrode, and metal ions are eluted from the positive electrode when the operating temperature of the battery is high. This is effective from the viewpoint of maintaining conductivity between substances.
  • the element ratio Si / Al between Si and Al is 0.3 or more and less than 1.0 in terms of metal ion adsorption ability and metal ion selectivity. It is preferably 4 or more and 0.6 or less, and more preferably 0.45 or more and 0.55 or less.
  • the Si / Al molar ratio is less than 0.3, the amount of Al that does not contribute to the enhancement of metal ion adsorption capacity becomes excessive, and the ion adsorption capacity of impurities is poor. If it is 1.0 or more, the amount of Si that does not contribute to the improvement of metal ion selectivity tends to be excessive, and the metal ion selectivity is lowered.
  • the element ratio Si / Al of Si and Al can be measured by an ordinary method using an ICP emission spectrometer (for example, ICP emission spectrometer: P-4010 manufactured by Hitachi, Ltd.).
  • ICP emission spectrometer for example, ICP emission spectrometer: P-4010 manufactured by Hitachi, Ltd.
  • the specific aluminum silicate according to the present embodiment preferably has a peak in the vicinity of 3 ppm in the 27Al-NMR spectrum.
  • the 27Al-NMR measuring apparatus for example, AV400WB type manufactured by Bruker BioSpin can be used, and specific measuring conditions are as follows.
  • FIG. 1 shows a 27Al-NMR spectrum of a specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
  • the specific aluminum silicate according to this embodiment preferably has a peak in the vicinity of 3 ppm in the 27Al-NMR spectrum.
  • the peak around 3 ppm is estimated to be a peak derived from 6-coordinated Al.
  • the peak near 55 ppm is estimated to be a peak derived from tetracoordinated Al.
  • the area ratio of the peak near 55 pm to the peak near 3 ppm in the 27Al-NMR spectrum is 25% or less. Preferably, it is 20% or less, more preferably 15% or less.
  • the specific aluminum silicate according to the present embodiment has an area ratio of a peak near 55 pm to a peak near 3 ppm in the 27Al-NMR spectrum from the viewpoint of metal ion adsorptivity and metal ion selectivity of 1%. Preferably, it is preferably 5% or more, more preferably 10% or more.
  • the specific aluminum silicate according to this embodiment preferably has peaks in the vicinity of ⁇ 78 ppm and in the vicinity of ⁇ 85 ppm in the 29Si-NMR spectrum.
  • Aluminum silicate showing such a specific 29Si-NMR spectrum is excellent in metal ion adsorption and metal ion selectivity.
  • a 29Si-NMR measuring apparatus for measuring a 29Si-NMR spectrum for example, an AV400WB type manufactured by Bruker BioSpin can be used, and specific measurement conditions are as follows.
  • Resonance frequency 79.5 MHz
  • Measuring method MAS (single pulse)
  • MAS rotation speed 6 kHz
  • Measurement area 24 kHz
  • Number of data points 2048 resolution (measurement area / number of data points): 5.8 Hz
  • Pulse width 4.7 ⁇ sec
  • Delay time 600 seconds
  • Chemical shift value criteria TMSP-d4 (3- (trimethylsilyl) (2,2,3,3-2H4) sodium propionate) 1.52
  • window function exponential function
  • Line Broadening coefficient 50 Hz
  • FIG. 2 shows 29Si-NMR spectra of specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
  • the specific aluminum silicate according to this embodiment preferably has peaks in the vicinity of ⁇ 78 ppm and in the vicinity of ⁇ 85 ppm in the 29Si-NMR spectrum.
  • the peak A that appears in the vicinity of ⁇ 78 ppm is derived from a specific aluminum silicate having a crystal structure such as imogolite and allophanes, and is considered to be caused by a structure of HO—Si— (OAl) 3.
  • the peak B appearing around ⁇ 85 ppm is considered to be a specific aluminum silicate having a clay structure or a specific aluminum silicate having an amorphous structure. Therefore, the specific aluminum silicate having peaks near 78 ppm and -85 ppm is a mixture or composite of the specific aluminum silicate having a crystal structure and the specific aluminum silicate having a viscosity structure or an amorphous structure. It is estimated to be.
  • aluminum silicate having a peak A that appears in the vicinity of ⁇ 78 ppm has many OH groups per unit mass. For this reason, it has been found that the aluminum silicate having the peak A that appears in the vicinity of ⁇ 78 ppm is excellent in water adsorption ability.
  • the inventors have newly found that this aluminum silicate has an excellent ability to adsorb metal ions, and in particular selectively adsorbs metal ions which adversely affect the battery. For this reason, in the lithium ion battery containing this specific aluminum silicate, the occurrence of short circuit is remarkably reduced, and as a result, it can be considered that the life characteristics are excellent.
  • the specific aluminum silicate according to this embodiment may not have a peak around ⁇ 110 ppm derived from the layered clay mineral.
  • having no peak means that the displacement from the baseline in the vicinity of ⁇ 110 ppm is below the noise level.
  • the specific aluminum silicate according to this embodiment has an area ratio of a peak A around ⁇ 78 ppm and a peak B around ⁇ 85 ppm in the 29Si-NMR spectrum (from the viewpoint of improving metal ion adsorption ability and metal ion selectivity).
  • Peak B / Peak A) is preferably 0.4 to 9.0, more preferably 1.5 to 9.0, still more preferably 2.0 to 9.0. It is more preferably 0.0 to 7.0, still more preferably 2.0 to 5.0, and particularly preferably 2.0 to 4.0.
  • a baseline is first drawn in the 29Si-NMR spectrum.
  • a straight line connecting -55 ppm and -140 ppm is taken as a baseline.
  • the area of peak A near ⁇ 78 ppm is the area of the region surrounded by the straight line passing through ⁇ 81 ppm perpendicular to the chemical shift axis and the base line, and the area of peak B is chemical through ⁇ 81 ppm. This is the area of a region surrounded by a straight line perpendicular to the shift axis and the base line.
  • FIG. 3 and 4 show an example of a transmission electron microscope (TEM) photograph of the specific aluminum silicate according to the present embodiment.
  • the specific aluminum silicate shown in FIG. 3 is a specific aluminum silicate according to Example 1 described later.
  • the specific aluminum silicate shown in FIG. 4 is a specific aluminum silicate according to Example 2 described later.
  • the specific aluminum silicate according to Example 1 does not have a tubular product having a length of 50 nm or more when observed at a magnification of 100,000 with a transmission electron microscope (TEM).
  • the specific aluminum silicate according to Example 2 is tubular so-called imogolite, as shown in FIG.
  • the specific aluminum silicate according to the present embodiment is a tubular product having a length of 50 nm or more when observed with a transmission electron microscope (TEM) at a magnification of 100,000 from the viewpoint of metal ion adsorption ability and metal ion selectivity. Is preferably absent.
  • TEM transmission electron microscope
  • Observation of a specific aluminum silicate with a transmission electron microscope (TEM) is performed at an acceleration voltage of 100 kV.
  • TEM transmission electron microscope
  • a solution after heating before the second washing step (desalting and solid separation) in the manufacturing method described later is dropped on a support for preparing a TEM observation sample, and then dried to form a thin film.
  • an observation sample is prepared using an appropriately diluted solution after the heat treatment so that a sufficient contrast can be obtained.
  • the specific aluminum silicate in which a tubular product as shown in FIG. 3 is not observed is manufactured by performing a heat treatment of silicate ions and aluminum ions at a specific concentration or more.
  • FIG. 5 is a drawing schematically showing a tubular so-called imogolite (first specific aluminum silicate described in a manufacturing method described later) 10 which is an example of the specific aluminum silicate according to the present embodiment.
  • the fiber structure tends to be formed by the tubular bodies 10 a, and the outer wall (outer periphery) of the tubular body 10 a forming the inner wall 20 in the tube of the tubular body 10 a and the gap 30 between the tubular body 10 a ridges. Surface) can be used as an adsorption site for metal ions.
  • the length of the tubular body 10a in the tube portion length direction is, for example, 1 nm to 10 ⁇ m.
  • the tubular body 10a has, for example, a circular tubular shape, and has an outer diameter of, for example, 1.5 nm to 3.0 nm and an inner diameter of, for example, 0.7 nm to 1.4 nm.
  • Powder X-ray diffraction is measured using CuK ⁇ rays as an X-ray source.
  • a powder X-ray diffractometer manufactured by Rigaku Corporation: Geigerflex RAD-2X (trade name) can be used.
  • FIG. 6 shows a powder X-ray diffraction spectrum of the specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
  • precipitation of aluminum hydroxide can be suppressed by making the heating temperature at the time of heat processing into 160 degrees C or less.
  • content of aluminum hydroxide can be adjusted by adjusting pH at the time of the desalting process by centrifugation.
  • the specific aluminum silicate according to this embodiment has a BET specific surface area of preferably 250 m 2 / g or more, more preferably 280 m 2 / g or more, and 300 m from the viewpoint of improving the metal ion adsorption ability. More preferably, it is 2 / g or more.
  • the BET specific surface area is 250 m 2 / g or more, the adsorbed amount of impurity ions and eluted ions per unit mass is increased, so that the efficiency is good and a high effect is obtained with a small amount.
  • the upper limit of the BET specific surface area is not particularly limited, but if the specific surface area is too large, the amount of moisture adsorbed in the air per unit mass will increase, so the BET specific surface area should be 1500 m 2 / g or less. Is preferably 1200 m 2 / g or less, more preferably 1000 m 2 / g or less.
  • the BET specific surface area of the specific aluminum silicate is measured from the nitrogen adsorption ability at 77K according to JIS Z 8830.
  • the evaluation apparatus for example, AUTOSORB-1 (trade name) manufactured by QUANTACHROME can be used.
  • AUTOSORB-1 trade name manufactured by QUANTACHROME
  • pretreatment for removing moisture by heating is first performed.
  • the measurement cell charged with 0.05 g of the measurement sample is depressurized to 10 Pa or less with a vacuum pump, heated at 110 ° C., held for 3 hours or more, and kept at a normal temperature while maintaining the depressurized state. Cool naturally to (25 ° C).
  • the evaluation temperature is 77K
  • the evaluation pressure range is measured as a relative pressure (equilibrium pressure with respect to saturated vapor pressure) of less than 1.
  • Certain aluminum silicates according to the present embodiment is preferably, 0.12 cm 3 / g or more that the total pore volume is 0.1 cm 3 / g or more More preferably, it is still more preferably 0.15 cm 3 / g or more.
  • the upper limit of the total pore volume is not particularly limited, but if the total pore volume is too large, the amount of moisture adsorbed in the air per unit mass increases, so the total pore volume is 1.5 cm 3. / G or less is preferable, 1.2 cm 3 / g or less is more preferable, and 1.0 cm 3 / g or less is still more preferable.
  • the total pore volume of the specific aluminum silicate is based on the BET specific surface area.
  • the gas adsorption amount closest to the relative pressure 1 is set to the liquid. Calculate by conversion.
  • the average pore diameter of the specific aluminum silicate according to this embodiment is preferably 1.5 nm or more. Since it moves to the site
  • the average pore diameter of the specific aluminum silicate is obtained on the basis of the BET specific surface area and the total pore volume, assuming that all the pores are composed of one cylindrical pore.
  • the specific aluminum silicate according to this embodiment preferably has a moisture content of 10% by mass or less, and more preferably 5% by mass or less.
  • a lithium ion secondary battery is constituted by having a water content of 10% by mass or less, generation of gas due to water causing electrolysis can be suppressed, and battery expansion can be suppressed.
  • the water content can be measured by the Karl Fischer method.
  • a commonly used drying method can be applied without any particular limitation. For example, a method of drying at about 100 ° C. to 300 ° C. for about 6 hours to 24 hours under atmospheric pressure can be mentioned.
  • the method for producing a specific aluminum silicate according to the present invention comprises (a) a step of mixing a solution containing silicate ions and a solution containing aluminum ions to obtain a reaction product, and (b) the reaction product, A step of desalting and separating the solid, (c) a step of subjecting the solid separated in step (b) to a heat treatment in an aqueous medium in the presence of an acid, and (d) a heat treatment in step (c). And a step of desalting and solid separation of the product obtained as described above, and having other steps as necessary.
  • the specific aluminum silicate from which the coexisting ions that inhibit the formation of the regular structure are removed is heat-treated in the presence of an acid, whereby the specific aluminum silicate having a regular structure is formed. It can be considered that the specific aluminum silicate has a regular structure, the affinity for unnecessary metal ions is improved, and the metal ion selectivity is enhanced while efficiently adsorbing the metal ions.
  • Step of obtaining reaction product In the step of obtaining reaction product, a solution containing silicate ions and a solution containing aluminum ions are mixed to contain a specific aluminum silicate and coexisting ions which are reaction products. A mixed solution is obtained.
  • silicate solution When synthesizing a specific aluminum silicate, silicate ions and aluminum ions are required as raw materials.
  • the silicic acid source constituting the solution containing silicate ions (hereinafter also referred to as “silicate solution”) is not particularly limited as long as silicate ions are generated when solvated. Examples thereof include, but are not limited to, tetraalkoxysilanes such as sodium orthosilicate, sodium metasilicate, and tetraethoxysilane.
  • the aluminum source constituting the solution containing aluminum ions is not particularly limited as long as aluminum ions are generated when solvated.
  • examples thereof include, but are not limited to, aluminum chloride, aluminum perchlorate, aluminum nitrate, and aluminum sec-butoxide.
  • a material that can easily be solvated with the silicate source and the aluminum source as raw materials can be appropriately selected and used.
  • water, ethanol or the like can be used. It is preferable to use water from the viewpoint of reducing the coexisting ions in the solution during the heat treatment and ease of handling.
  • the element ratio Si / Al of the Si and Al in the mixed solution is 0.3 to less than 1.0 in molar ratio in accordance with the element ratio Si / Al of Si and Al in the specific aluminum silicate obtained. It adjusts so that it may become 0.4 or more and 0.6 or less, More preferably, it adjusts so that it may become 0.45 or more and 0.55 or less.
  • the element ratio Si / Al is 0.3 or more and less than 1.0, a specific aluminum silicate having a desired regular structure is easily synthesized.
  • the silicon atom concentration of the silicate solution is not particularly limited. Preferably, it is 1 mmol / L to 1000 mmol / L.
  • productivity is improved and specific aluminum silicate can be produced efficiently. Moreover, productivity improves more according to a silicon atom concentration as the silicon atom concentration of a silicic acid solution is 1000 mmol / L or less.
  • the aluminum atom concentration of the aluminum solution is not particularly limited. Preferably, it is 100 mmol / L to 1000 mmol / L.
  • the productivity is improved and specific aluminum silicate can be efficiently produced. Further, when the aluminum atom concentration is 1000 mmol / L or less, the productivity is further improved according to the aluminum atom concentration.
  • a solution containing silicate ions and a solution containing aluminum ions are mixed to produce a specific aluminum silicate containing coexisting ions as a reaction product, and then the specific aluminum silicate containing the coexisting ions is desalted.
  • a first washing step for solid separation In the first washing step, at least a part of the coexisting ions is removed from the mixed solution to reduce the coexisting ion concentration in the mixed solution. By performing the first cleaning step, it is easy to form a desired specific aluminum silicate in the synthesis step.
  • desalting and solid separation include anions other than silicate ions derived from a silicate source and an aluminum source (for example, chloride ions and nitrate ions) and cations other than aluminum ions (for example, sodium ions).
  • anions other than silicate ions derived from a silicate source and an aluminum source for example, chloride ions and nitrate ions
  • cations other than aluminum ions for example, sodium ions
  • the first cleaning step is preferably performed so that the concentration of the coexisting ions is not more than a predetermined concentration.
  • the electrical conductivity of the dispersion is 4.0 S / m. It is preferable to carry out so that it is less than or equal to 1.0 mS / m or more and 3.0 S / m or less, more preferably 1.0 mS / m or more and 2.0 S / m or less. Is more preferable.
  • the desired specific aluminum silicate tends to be more easily formed in the synthesis step.
  • the electrical conductivity is measured at normal temperature (25 ° C.) using FORI 55 manufactured by HORIBA Co., Ltd. and a general electrical conductivity cell of 9382-10D.
  • the first washing step includes a step of dispersing the specific aluminum silicate in an aqueous medium to obtain a dispersion, a step of adjusting the pH of the dispersion to 5 to 7, and a step of precipitating the specific aluminum silicate Are preferably included.
  • the first washing step when the first washing step is performed using centrifugation, it can be performed as follows.
  • the pH is adjusted to 5 to 8 by adding alkali or the like to the mixed solution.
  • the supernatant solution After centrifuging the pH-adjusted solution, the supernatant solution is discharged and the solid is separated as a gel-like precipitate.
  • the separated solid is redispersed in a solvent. In that case, it is preferable to return to the volume before centrifugation.
  • the concentration of the coexisting ions can be reduced to a predetermined concentration or less by repeating the operations of desalting and solid separation by centrifugal separation of the redispersed dispersion in the same manner.
  • the pH is adjusted to, for example, 5 to 8, but preferably 5.5 to 6.8, and more preferably 5.8 to 6.5.
  • the alkali used for pH adjustment is not particularly limited. For example, sodium hydroxide and ammonia are preferable.
  • the centrifugation conditions are appropriately selected according to the production scale and the container used. For example, it can be 1 to 30 minutes at 1200 G or more at room temperature. Specifically, for example, in the case of using SUPREMA23 manufactured by TOMY as a centrifugal separator and its standard rotor NA-16, it can be set at 3000 rpm (1450 G) or more for 5 to 10 minutes at room temperature.
  • a solvent that can easily be solvated with the raw material can be appropriately selected and used.
  • water, ethanol, or the like can be used. From the viewpoint of the reduction of coexisting ions and ease of handling, water is preferably used, and pure water is more preferably used. It should be noted that pH adjustment is preferably omitted when repeated washing is performed a plurality of times.
  • the number of treatments for desalting and solid separation in the first washing step may be appropriately set according to the remaining amount of coexisting ions. For example, it can be 1 to 6 times. If the washing is repeated about three times, the residual amount of coexisting ions is so small that it does not affect the synthesis of the desired specific aluminum silicate.
  • PH measurement at the time of pH adjustment can be performed with a pH meter using a general glass electrode.
  • a general glass electrode Specifically, for example, trade name: MODEL (F-51) manufactured by HORIBA, Ltd. can be used.
  • a specific aluminum silicate having a regular structure is formed by heat-treating a solution (dispersion) containing the specific aluminum silicate with reduced coexisting ions in the first washing step in the presence of an acid. be able to.
  • the synthesis step may be performed as a dilute solution by appropriately diluting the solid separated in the first washing step, or may be carried out as a high-concentration solution after solid separation in the first washing step.
  • a specific aluminum silicate having a structure in which a regular structure is extended into a tubular shape as shown in FIG. 4 (hereinafter also referred to as “first specific aluminum silicate”). ) Can be obtained. Further, by carrying out the synthesis step in a high concentration solution, a specific aluminum silicate having a viscosity structure and an amorphous structure in addition to a regular structure as shown in FIG. Silicate "). In addition, it replaces with the 2nd specific aluminum silicate growing in the tubular thing 50 nm or more in length, and it is estimated that the formation of a viscosity structure and an amorphous structure is increasing.
  • Both the first and second specific aluminum silicates have a specific regular structure, thereby exhibiting excellent metal ion adsorption ability and metal ion selectivity.
  • the silicon atom concentration can be 20 mmol / L or less and the aluminum atom concentration can be 60 mmol / L or less.
  • the silicon atom concentration is 0.1 mmol / L or more and 10 mmol / L or less and the aluminum atom concentration is 0.1 mmol / L or more and 34 mmol / L or less.
  • the atomic concentration is from 0.1 mmol / L to 2 mmol / L and the aluminum atomic concentration is from 0.1 mmol / L to 7 mmol / L.
  • the first specific aluminum silicate can be efficiently produced.
  • the silicon atom concentration can be 100 mmol / L or more and the aluminum atom concentration can be 100 mmol / L or more.
  • the silicon atom concentration is preferably 120 mmol / L or more and 2000 mmol / L or less
  • the aluminum atom concentration is preferably 120 mmol / L or more and 2000 mmol / L or less
  • the silicon atom concentration is 150 mmol. More preferably, the aluminum atom concentration is 150 mmol / L or more and 1500 mmol / L or less.
  • the second specific aluminum silicate can be efficiently produced, and the productivity of the specific aluminum silicate is also improved. To do.
  • the silicon atom concentration and the aluminum atom concentration are the silicon atom concentration and the aluminum element concentration after adjusting the pH to a predetermined range by adding an acidic compound described later.
  • the silicon atom concentration and the aluminum atom concentration are measured using an ICP emission spectrometer (for example, ICP emission spectrometer manufactured by Hitachi, Ltd .: P-4010).
  • a solvent may be added.
  • the solvent one that can easily be solvated with the raw material can be appropriately selected and used. Specifically, water, ethanol, etc. can be used, but the coexisting ions in the solution during the heat treatment can be reduced. From the viewpoint of ease of handling, it is preferable to use water.
  • the synthesis step at least one acidic compound is added before the heat treatment.
  • the pH after adding the acidic compound is not particularly limited. From the viewpoint of efficiently obtaining the desired specific aluminum silicate, the pH is preferably from 3 to less than 7, and more preferably from 3 to 5.
  • the acidic compound added in the synthesis step is not particularly limited, and may be an organic acid or an inorganic acid. Among these, it is preferable to use an inorganic acid. Specific examples of the inorganic acid include hydrochloric acid, perchloric acid, nitric acid and the like. Considering the reduction of coexisting ion species in the solution during the subsequent heat treatment, it is preferable to use an acidic compound that generates an anion similar to the anion contained in the used aluminum source.
  • a specific aluminum silicate having a desired structure can be obtained by performing a heat treatment after adding an acidic compound.
  • the heating temperature is not particularly limited. From the viewpoint of efficiently obtaining the desired specific aluminum silicate, the temperature is preferably from 80 ° C to 160 ° C.
  • the heating temperature is 160 ° C. or lower, precipitation of boehmite (aluminum hydroxide) tends to be suppressed.
  • the heating temperature is 80 ° C. or higher, the synthesis rate of the desired specific aluminum silicate is improved, and the desired specific aluminum silicate tends to be produced more efficiently.
  • the heating time is not particularly limited. From the viewpoint of more efficiently obtaining a specific aluminum silicate having a desired structure, it is preferably within 96 hours (4 days).
  • the desired specific aluminum silicate can be more efficiently produced.
  • the second washing step only needs to be able to remove at least a part of anions other than silicate ions and cations other than aluminum ions, and may be the same operation as the first washing step before the synthesis step or a different operation. Good.
  • the second washing step is preferably performed so that the concentration of coexisting ions is not more than a predetermined concentration.
  • the electrical conductivity of the dispersion is 4.0 S / m. It is preferable to carry out so that it is less than or equal to 1.0 mS / m or more and 3.0 S / m or less, more preferably 1.0 mS / m or more and 2.0 S / m or less. Is more preferable.
  • the second washing step is performed using centrifugation, for example, it can be performed as follows.
  • the pH is adjusted to 5 to 10 by adding alkali or the like to the mixed solution.
  • the supernatant solution is discharged and the solid is separated as a gel-like precipitate.
  • the solid separated is then redispersed in a solvent. In that case, it is preferable to return to the volume before centrifugation.
  • the concentration of the coexisting ions can be reduced to a predetermined concentration or less by repeating the operations of desalting and solid separation by centrifugal separation of the redispersed dispersion in the same manner.
  • the pH is adjusted to, for example, 5 to 10, preferably 8 to 10.
  • the alkali used for pH adjustment is not particularly limited.
  • sodium hydroxide and ammonia are preferable.
  • the centrifugation conditions are appropriately selected according to the production scale and the container used. For example, it can be 1 to 30 minutes at 1200 G or more at room temperature. Specifically, for example, in the case of using SUPREMA23 manufactured by TOMY as a centrifugal separator and its standard rotor NA-16, it can be set at 3000 rpm (1450 G) or more for 5 to 10 minutes at room temperature.
  • a solvent that can easily be solvated with the raw material can be appropriately selected and used.
  • water, ethanol, or the like can be used. From the viewpoint of ease of handling, it is preferable to use water, and it is more preferable to use pure water.
  • pH adjustment is preferably omitted when repeated washing is performed a plurality of times.
  • the number of treatments for desalting and solid separation in the second washing step may be set according to the residual amount of coexisting ions, but is preferably 1 to 6 times, and if the washing is repeated about 3 times, the coexistence in the specific aluminum silicate The remaining amount of ions is sufficiently reduced.
  • the concentration of chloride ions and sodium ions that particularly affect the adsorption ability of metal ions is reduced. That is, when the aluminum silicate after washing in the second washing step is prepared by dispersing the aluminum silicate in water to prepare an aqueous dispersion having a concentration of 400 mg / L, the chloride ion concentration in the aqueous dispersion is 100 mg. / L or less and a sodium ion concentration of 100 mg / L or less are preferable. When the chloride ion concentration is 100 mg / L or less and the sodium ion concentration is 100 mg / L or less, the adsorption ability can be further improved.
  • the chloride ion concentration is more preferably 50 mg / L or less, and still more preferably 10 mg / L or less.
  • the sodium ion concentration is more preferably 50 mg / L or less, and still more preferably 10 mg / L or less. Chloride ion concentration and sodium ion concentration can be adjusted according to the number of treatments in the washing step and the type of alkali used for pH adjustment.
  • the chloride ion concentration and sodium ion concentration are measured under normal conditions by ion chromatography (for example, DX-320 and DX-100 manufactured by Dionex).
  • concentration of the dispersion of the specific aluminum silicate is based on the mass of the solid obtained by drying the separated solid at 110 degrees for 24 hours.
  • the “dispersion after the second washing step” described here means a dispersion in which the volume is returned to the volume before the second washing step after the second washing step by using a solvent.
  • a solvent that easily solvates with the raw material can be appropriately selected and used. Specifically, water, ethanol or the like can be used, but the residual amount of coexisting ions in the specific aluminum silicate It is preferable to use water from the viewpoint of reduction of the amount and ease of handling.
  • the BET specific surface area of the specific aluminum silicate according to the present invention is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution) Then, the specific aluminum silicate remaining as a gel-like precipitate is redispersed in a solvent, and the process of returning to the volume before centrifugation is repeated once or a plurality of times.
  • the total pore volume of the specific aluminum silicate is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution).
  • the specific aluminum silicate remaining as a gel-like precipitate can be adjusted by a method of redispersing in a solvent and returning to the volume before centrifugation once or a plurality of times.
  • the average pore diameter of the specific aluminum silicate is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution).
  • the specific aluminum silicate remaining as a gel-like precipitate can be adjusted by a method of redispersing in a solvent and returning to the volume before centrifugation once or a plurality of times.
  • the positive electrode for a lithium ion secondary battery of the present invention is provided with the specific aluminum silicate on the surface thereof. Since the specific aluminum silicate is applied to the surface of the positive electrode, impurity ions ionized at the positive electrode are captured, so that it is possible to suppress the metal ions from being reduced and the metal from being precipitated at the negative electrode. Thereby, the short circuit of a battery is suppressed. Moreover, since it is suppressed that a metal ion elutes from a positive electrode, the electroconductivity between positive electrode active materials can be hold
  • a layer containing a positive electrode active material (hereinafter sometimes referred to as a “positive electrode layer”) is provided on a current collector.
  • a positive electrode provided with a layer containing a specific aluminum silicate on the surface can be given.
  • the layer containing specific aluminum silicate if the specific aluminum silicate is provided to the surface of the positive electrode layer, it may not be layered.
  • a normal current collector used for a positive electrode for a lithium ion secondary battery can be applied.
  • a normal current collector used for a positive electrode for a lithium ion secondary battery can be applied.
  • aluminum, titanium, stainless steel A band-like material made of a metal such as steel or an alloy such as a foil shape, a perforated foil shape, or a mesh shape can be used.
  • Positive electrode layer The positive electrode layer is provided on the current collector and contains a positive electrode active material.
  • a positive electrode active material usually used for a positive electrode for a lithium ion secondary battery can be applied.
  • a positive electrode active material usually used for a positive electrode for a lithium ion secondary battery can be applied.
  • metal compounds, metal oxides, metal sulfides that can be doped or intercalated with lithium ions Or a conductive polymer material for example, metal compounds, metal oxides, metal sulfides that can be doped or intercalated with lithium ions Or a conductive polymer material.
  • lithium cobaltate LiCoO 2
  • lithium nickelate LiNiO 2
  • lithium manganate LiMnO 2
  • lithium manganese spinel LiMn 2 O 4
  • lithium vanadium compound V 2 O 5 , V 6 O 13 , VO 2 , MnO 2
  • TiO 2 , MoV 2 O 8 TiS 2 , V 2 S 5 , VS 2 , MoS 2 , MoS 3 , Cr 3 O 8 , Cr 2 O 5
  • olivine type LiMPO 4 M: Co, Ni, Mn Fe
  • polyacetylene polyaniline
  • polypyrrole polythiophene
  • polyacene polyacene
  • polyacetylene polyaniline
  • polypyrrole polythioph
  • the positive electrode layer may contain a binder.
  • the binder include styrene-butadiene copolymer; ethylenically unsaturated carboxylic acid ester (for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylonitrile, hydroxyethyl (meth ) Acrylate, etc.), and (meth) acrylic copolymers obtained by copolymerizing ethylenically unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, etc.); polyvinylidene fluoride , Polymer compounds such as polyethylene oxide, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, polyimide, and polyamideimide.
  • Examples of a method for forming the positive electrode layer on the current collector include a method in which a positive electrode mixture slurry containing the positive electrode active material, the binder, and a solvent is applied on the current collector and dried.
  • the paste-like positive electrode mixture slurry may be formed into a sheet shape, a pellet shape, or the like and integrated with the current collector.
  • the viscosity of the positive electrode mixture slurry is preferably adjusted as appropriate in accordance with the coating method.
  • the solvent examples include alcohols, glycols, cellosolves, amino alcohols, amines, ketones, carboxylic acid amides, phosphoric acid amides, sulfoxides, carboxylic acid esters, phosphoric acid esters, and ethers. , Nitriles, water and the like.
  • a highly polar solvent In order to obtain the solubility of the binder and the dispersion stability of the conductive agent, it is preferable to use a highly polar solvent.
  • the solvent include amide solvents obtained by dialkylating nitrogen such as N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, Examples include, but are not limited to, N-methylpyrrolidone, hexamethylphosphoric triamide, dimethyl sulfoxide, and the like. Two or more types can be used in combination.
  • a thickener may be added to the positive electrode mixture slurry in order to adjust the viscosity.
  • the thickener for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
  • a conductive agent may be mixed in the positive electrode mixture slurry as necessary.
  • the conductive agent include carbon blacks such as ketjen black, acetylene black, channel black, furnace black, lamp black, and thermal black; natural graphite such as flake graphite, graphite such as artificial graphite, and expanded graphite
  • Conductive fibers such as carbon fibers and metal fibers
  • metal powders such as copper, silver, nickel, and aluminum
  • organic conductive materials such as polyphenylene derivatives
  • the method for applying the positive electrode mixture slurry to the current collector is not particularly limited, and a known method can be used. Specific examples include a die coating method, a dip coating method, a roll coating method, a doctor coating method, a spray coating method, a gravure coating method, a screen printing method, and an electrostatic coating method. Moreover, you may perform the rolling process by a lithographic press, a calender roll, etc. after application
  • the integration of the positive electrode mixture slurry and the current collector formed into a sheet shape, a pellet shape, or the like can be performed by a known method such as a roll, a press, or a combination thereof.
  • the thickness of the positive electrode layer is generally 1 ⁇ m or more and 500 ⁇ m or less, preferably 10 ⁇ m or more and 300 ⁇ m or less.
  • the layer containing the specific aluminum silicate is provided on the positive electrode layer, and may be formed by any method.
  • the specific aluminum silicate can be uniformly dispersed on the positive electrode, and thereby, unnecessary metal ions can be effectively adsorbed. Preferably it is formed.
  • the dispersion can be prepared, for example, by kneading the specific aluminum silicate together with a binder and a solvent by a dispersing device such as a stirrer, a ball mill, a super sand mill, or a pressure kneader. This dispersion can be applied onto the positive electrode layer to form a layer containing a specific aluminum silicate.
  • a dispersing device such as a stirrer, a ball mill, a super sand mill, or a pressure kneader.
  • the method for applying the dispersion on the positive electrode layer is not particularly limited.
  • known methods such as a metal mask printing method, an electrostatic coating method, a dip coating method, a spray coating method, a roll coating method, a doctor blade method, a gravure coating method, and a screen printing method can be used.
  • After the application it is preferable to perform a rolling process using a flat plate press, a calender roll or the like, if necessary.
  • Examples of the solvent for the dispersion include water, 1-methyl-2-pyrrolidone, alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2 -Methyl-2-propanol, etc.), and water is more preferable from the viewpoint of reducing environmental burden.
  • alcohols methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2 -Methyl-2-propanol, etc.
  • the content of the specific aluminum silicate in the dispersion is, for example, preferably 0.01% by mass to 50% by mass, more preferably 0.1% by mass to 30% by mass. More preferably, the content is from 20% by mass to 20% by mass.
  • Application amount of the specific aluminum silicate in the positive electrode for a lithium ion secondary battery it is preferably, 0.05g / m 2 ⁇ 30g / m 2 is 0.01g / m 2 ⁇ 50g / m 2 about More preferably, it is more preferably 0.1 g / m 2 to 20 g / m 2 .
  • the dispersion preferably further contains a binder.
  • the specific aluminum silicate is fixed to the positive electrode by adding a binder to the dispersion of the specific aluminum silicate. For this reason, when producing a battery, since specific aluminum silicate does not fall off and can exist on a positive electrode also at the time of charging / discharging, an unnecessary metal ion can be adsorb
  • the binder to be contained in the dispersion is not particularly limited, but is preferably a binder used for the positive electrode material layer as a binder from the viewpoint of a battery constituent material.
  • the content ratio of the binder in the layer containing the specific aluminum silicate is preferably 0.1 parts by mass to 15 parts by mass with respect to 100 parts by mass in total of the specific aluminum silicate and the binder. More preferably, it is 3 to 10 parts by mass.
  • the content ratio of the binder is 0.1 parts by mass or more
  • the specific aluminum silicate is effectively fixed to the positive electrode, and the effect of providing the specific aluminum silicate is continuously obtained.
  • suction efficiency per mass can be raised because it is 15 mass parts or less.
  • a thickener may be added to the dispersion to adjust the viscosity.
  • the thickener for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
  • an underlayer for improving the adhesion between the current collector and the positive electrode layer may be provided between the current collector and the positive electrode layer.
  • the underlayer preferably contains a polymer that does not dissolve or swell in the solvent of the electrolytic solution, and may contain a conductive substance in order to reduce the electrical resistance of the electrode and ensure conductivity.
  • the lithium ion secondary battery of this invention is comprised including the above-mentioned positive electrode, a negative electrode, and electrolyte solution.
  • the specific aluminum silicate is provided on the surface.
  • Negative electrode As an aspect of a negative electrode, the thing provided with the layer (henceforth a "negative electrode layer”) containing a negative electrode active material on the electrical power collector is mentioned, for example.
  • a normal current collector used for a negative electrode for a lithium ion secondary battery can be applied.
  • aluminum, copper, nickel, titanium, stainless steel Or the like may be used in the form of a foil, a punched foil, a mesh or the like.
  • a porous material such as porous metal (foamed metal) or carbon paper can also be used.
  • the negative electrode layer is provided on the current collector and contains a negative electrode active material.
  • negative electrode active material normal materials used for negative electrodes for lithium ion secondary batteries can be applied.
  • carbon materials, metal compounds, metal oxides, metal sulfides capable of doping or intercalating lithium ions can be used.
  • conductive polymer materials For example, natural graphite, artificial graphite, silicon, lithium titanate and the like can be used alone or in combination.
  • the negative electrode may contain a binder.
  • the binder is not particularly limited.
  • styrene-butadiene copolymer (meth) acrylic copolymer [ethylenically unsaturated carboxylic acid ester (for example, methyl (meth) acrylate, ethyl (meth) acrylate, Butyl (meth) acrylate, hydroxyethyl (meth) acrylate, etc.), (meth) acrylonitrile, ethylenically unsaturated carboxylic acid (for example, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, etc.) Copolymer obtained], polyvinylidene fluoride, polyethylene oxide, polyepichlorohydrin, polyphosphazene, polyimide, polyamideimide, and the like.
  • carboxylic acid ester for example, methyl (meth) acrylate, ethyl (meth) acrylate
  • a negative electrode mixture slurry is prepared by kneading the negative electrode active material and the binder together with a solvent by a dispersing device such as a stirrer, a ball mill, a super sand mill, and a pressure kneader. And a method of applying this onto the current collector and drying it.
  • the paste-like negative electrode mixture slurry may be formed into a sheet shape, a pellet shape, or the like and integrated with the current collector.
  • the binder content in the negative electrode layer of the negative electrode is preferably 0.5 parts by mass to 20 parts by mass with respect to 100 parts by mass in total of the negative electrode active material and the binder, and is 1 part by mass to 10 parts by mass. It is more preferable.
  • the content ratio of the binder is 0.5% by mass or more, the adhesion is good, and the negative electrode is prevented from being broken due to expansion / contraction during charge / discharge. On the other hand, it can suppress that electrode resistance becomes large because it is 20 mass% or less.
  • a conductive agent may be mixed in the negative electrode mixture slurry as necessary.
  • the conductive agent include carbon black, graphite, acetylene black, or conductive oxides and nitrides.
  • the amount of the conductive agent used may be about 0.1% by mass to 20% by mass with respect to the negative electrode active material.
  • a thickener may be added to the negative electrode mixture slurry in order to adjust the viscosity.
  • the thickener for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
  • the method for applying the negative electrode mixture slurry to the current collector is not particularly limited.
  • known methods such as a metal mask printing method, an electrostatic coating method, a dip coating method, a spray coating method, a roll coating method, a doctor blade method, a gravure coating method, and a screen printing method can be used.
  • After the application it is preferable to perform a rolling process using a flat plate press, a calender roll or the like, if necessary.
  • the integration of the negative electrode mixture slurry and the current collector formed into a sheet shape, a pellet shape or the like can be performed by a known method such as a roll, a press, or a combination thereof.
  • the thickness of the negative electrode layer is generally 1 ⁇ m or more and 500 ⁇ m or less, preferably 10 ⁇ m or more and 300 ⁇ m or less.
  • the negative electrode layer formed on the current collector and the negative electrode layer integrated with the current collector are preferably heat-treated according to the binder used.
  • heat treatment is preferably performed at 100 to 180 ° C.
  • heat treatment is preferably performed at 150 to 450 ° C.
  • This heat treatment increases the strength by removing the solvent and curing the binder, and improves the adhesion between the particles and between the particles and the current collector.
  • These heat treatments are preferably performed in an inert atmosphere such as helium, argon, nitrogen, or a vacuum atmosphere in order to prevent oxidation of the current collector during the treatment.
  • the negative electrode is pressure-pressed (pressure treatment) after the heat treatment.
  • the electrode density can be adjusted by applying pressure treatment.
  • the electrode density is preferably 1.0 g / cm 3 to 2.0 g / cm 3 .
  • Electrolyte used for the lithium ion secondary battery of the present invention is not particularly limited, and a known one can be used.
  • a non-aqueous lithium ion secondary battery is obtained by using an electrolytic solution in which an electrolyte is dissolved in an organic solvent.
  • lithium salts that generate anions that are difficult to solvate such as LiC (CF 3 SO 2 ) 3 , LiCl, and LiI.
  • the concentration of the electrolyte is not particularly limited.
  • the electrolyte is preferably 0.3 to 5 mol, more preferably 0.5 to 3 mol, and particularly preferably 0.8 to 1.5 mol with respect to 1 L of the electrolyte. preferable.
  • organic solvent examples include carbonates (propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, methyl propyl carbonate, butyl methyl carbonate, ethyl propyl carbonate, butyl ethyl carbonate.
  • the organic solvent may be used alone or as a mixed solvent of two or more.
  • the lithium ion secondary battery of the present invention may have a separator.
  • a separator for example, a nonwoven fabric mainly composed of polyolefin such as polyethylene and polypropylene, cloth, microporous film, or a combination thereof can be used.
  • the positive electrode and the negative electrode of the lithium ion secondary battery to be manufactured are not in direct contact, it is not necessary to use a separator.
  • the structure of the lithium ion secondary battery of the present invention is not particularly limited. Usually, a positive electrode and a negative electrode, and a separator provided as necessary are wound in a flat spiral shape to form a wound electrode group. In general, these are laminated as a flat plate to form a laminated electrode plate group, and the electrode plate group is generally enclosed in an exterior body.
  • the lithium ion secondary battery of the present invention is not particularly limited, but is used as a paper-type battery, a button-type battery, a coin-type battery, a laminated battery, a cylindrical battery, a square battery, or the like.
  • Examples 1 to 4 and Comparative Examples 1 to 3 below metal ion adsorption ability of specific aluminum silicate in water was evaluated as a preliminary test.
  • the model electrolyte was used as a model electrolyte. The metal ion adsorption ability was evaluated.
  • Example 7 a lithium ion secondary battery was produced, and the initial capacity, charge / discharge characteristics, and impedance were measured.
  • Example 1 ⁇ Preparation of aluminum silicate> A concentration: 350 mmol / L sodium orthosilicate aqueous solution (500 mL) was added to a 700 mmol / L aluminum chloride aqueous solution (500 mL), and the mixture was stirred for 30 minutes. To this solution, 330 mL of an aqueous sodium hydroxide solution having a concentration of 1 mol / L was added to adjust the pH to 6.1.
  • centrifugal separation was performed for 5 minutes at a rotation speed of 3,000 rpm using a TOMY Corporation: Suprema 23 and standard rotor NA-16 as a centrifugal separator. After centrifugation, the supernatant solution was discharged, the gel precipitate was redispersed in pure water, and returned to the volume before centrifugation. Such desalting treatment by centrifugation was performed three times.
  • the gel-like precipitate obtained after the third desalting of the desalting treatment was dispersed in pure water so as to have a concentration of 60 g / L, using HORIBA: F-55 and conductivity cell: 9382-10D.
  • the electrical conductivity measured at room temperature (25 ° C.) was 1.3 S / m.
  • the gel-like precipitate obtained after the third desalting of the desalting treatment was dispersed in pure water so as to have a concentration of 60 g / L, using HORIBA: F-55 and conductivity cell: 9382-10D.
  • the electrical conductivity measured at room temperature (25 ° C.) was 0.6 S / m.
  • sample A The gel precipitate obtained after the third desalting of the desalting treatment was dried at 60 ° C. for 16 hours to obtain 30 g of powder. This powder was designated as sample A.
  • As the evaluation device AUTASORB-1 (trade name) manufactured by QUANTACHROME was used. When performing these measurements, after pre-treatment of the sample described later, the evaluation temperature is 77K, and the evaluation pressure range is less than 1 in relative pressure (equilibrium pressure with respect to the saturated vapor pressure).
  • the measurement cell charged with 0.05 g of sample A was automatically degassed and heated with a vacuum pump.
  • the detailed conditions of this treatment were set such that the pressure was reduced to 10 Pa or less, heated at 110 ° C., held for 3 hours or more, and then naturally cooled to room temperature (25 ° C.) while maintaining the reduced pressure.
  • the BET specific surface area of Sample A was 363 m 2 / g, the total pore volume was 0.22 cm 3 / g, and the average pore diameter was 2.4 nm.
  • FIG. 1 shows the 27Al-NMR spectrum of Sample A. As shown in FIG. 1, it had a peak around 3 ppm. A slight peak was observed around 55 ppm. The area ratio of the peak near 55 ppm to the peak near 3 ppm was 15%.
  • FIG. 2 shows the 29Si-NMR spectrum of Sample A. As shown in FIG. 2, there were peaks at around -78 ppm and around -85 ppm.
  • FIG. 3 shows a transmission electron microscope (TEM) photograph of sample A observed at a magnification of 100,000.
  • the TEM observation was performed using a transmission electron microscope (H-7100FA, manufactured by Hitachi High-Technologies Corporation) at an acceleration voltage of 100 kV.
  • a sample A to be observed with TEM was prepared as follows. That is, the solution after heating (aluminum silicate concentration of 47 g / L) before the final desalting treatment process was diluted 10 times with pure water and subjected to ultrasonic irradiation for 5 minutes. It was prepared by dropping it onto a support and then drying it naturally to form a thin film.
  • Metal ion adsorption capacity in water was evaluated by ICP emission spectroscopic analysis (ICP emission spectrophotometer: P-4010 (manufactured by Hitachi, Ltd.)).
  • a 100 ppm metal ion solution was prepared for each of Li + , Ni 2+, or Mn 2+ using each metal sulfate and pure water. It added so that the sample A might be 1.0 mass% with respect to the prepared solution, and it left still, after mixing sufficiently. Then, each metal ion concentration before and after the addition of sample A was measured by ICP emission spectroscopic analysis.
  • Sample B was commercially available activated carbon (manufactured by Wako Pure Chemical Industries, Ltd., activated carbon, crushed, 2 to 5 mm). Regarding the metal ion adsorption capacity in water, the concentrations after addition of Sample B were 50 ppm for Ni 2+ , 60 ppm for Mn 2+ , and 100 ppm for Li + .
  • Sample C was a commercially available silica gel (manufactured by Wako Pure Chemical Industries, Ltd., small granular (white)). Regarding the metal ion adsorption ability in water, the concentrations after addition of Sample C were 100 ppm for Ni 2+ , 100 ppm for Mn 2+ , and 80 ppm for Li + .
  • Example 2 ⁇ Preparation of aluminum silicate> A concentration: 74 mmol / L sodium orthosilicate aqueous solution (500 mL) was added to an aluminum chloride aqueous solution (500 mL) having a concentration of 180 mmol / L, followed by stirring for 30 minutes. To this solution, 93 mL of a 1 mol / L sodium hydroxide aqueous solution was added to adjust the pH to 7.0.
  • centrifugal separation was performed for 5 minutes at a rotation speed of 3,000 rpm using a TOMY Corporation: Suprema 23 and standard rotor NA-16 as a centrifugal separator. After centrifugation, the supernatant solution was discharged, the gel precipitate was redispersed in pure water, and returned to the volume before centrifugation. Such desalting treatment by centrifugation was performed three times.
  • the gel-like precipitate obtained after the third desalting of the desalting treatment was adjusted so as to have a concentration of 60 g / L, and it was used at normal temperature using FORI 55: F-55 and conductivity cell: 9382-10D.
  • the electrical conductivity was measured at 25 ° C. and found to be 1.3 S / m.
  • Pure water was added to the gel-like precipitate obtained after the supernatant was discharged for the third time in the desalting treatment to make the volume 12 L.
  • the silicon atom concentration and the aluminum atom concentration in the solution at this time were measured using an ICP emission spectrometer: P-4010 (manufactured by Hitachi, Ltd.), the silicon atom concentration was 2 mmol / L and the aluminum atom concentration was 4 mmol. / L.
  • the gel-like precipitate obtained after the third desalting of the desalting treatment was adjusted so as to have a concentration of 60 g / L, and it was used at normal temperature using FORI 55: F-55 and conductivity cell: 9382-10D.
  • the electric conductivity was measured at 25 ° C., it was 0.6 S / m.
  • the BET specific surface area of Sample E was 323 m 2 / g, the total pore volume was 0.22 cm 3 / g, and the average pore diameter was 2.7 nm.
  • FIG. 1 shows the 27Al-NMR spectrum of Sample E. As shown in FIG. 1, it had a peak around 3 ppm. A slight peak was observed around 55 ppm. The area ratio of the peak around 55 ppm to the peak around 3 ppm was 4%.
  • FIG. 2 shows the 29Si-NMR spectrum of Sample E. As shown in FIG. 2, there were peaks near ⁇ 78 ppm and ⁇ 85 ppm. The peak areas around ⁇ 78 ppm and ⁇ 85 ppm were measured by the above method. As a result, when the area of peak A near ⁇ 78 ppm was 1.00, the area of peak B near ⁇ 85 ppm was 0.44.
  • FIG. 4 the transmission electron microscope (TEM) photograph when the sample E is observed by 100,000 times by the same method as Example 1 is shown.
  • TEM transmission electron microscope
  • Example 3 The sample A prepared in Example 1 was used, and the ability to adsorb metal ions in water was evaluated by the method described in Example 1 except that the addition amount of Sample A was changed as shown in the following table. The results are shown in the table below.
  • Example 4 Using the sample A prepared in Example 1, the metal ion adsorption ability in water was evaluated by the method described in Example 1 except that the metal ion species was changed to Cu 2+ and the metal ion adjustment concentration was changed to 400 ppm. . The pH at this time was 5.1. The concentration after addition of Sample A was 160 ppm for Cu 2+ .
  • DEC diethyl carbonate
  • EC ethylene carbonate
  • the specific aluminum silicates of Examples 1 and 2 exhibited Ni 2+ ion adsorption ability superior to silica gel, zeolite 4A, and zeolite 13X.
  • Example 6 The Ni 2+ ion adsorption ability in the model electrolyte was evaluated by the method described in Example 5 except that the amount of sample A added was changed as shown in the table below. The results are shown in the table below.
  • the positive electrode active material used in this example is LiMn 2 O 4 powder having an average particle size of 20 ⁇ m and a maximum particle size of 80 ⁇ m.
  • This positive electrode active material, natural graphite, and a 1-methyl-2-pyrrolidone solution of polyvinylidene fluoride were mixed and sufficiently kneaded to obtain a positive electrode slurry.
  • the mixing ratio of LiMn 2 O 4 , natural graphite, and polyvinylidene fluoride was 90: 6: 4 by mass ratio.
  • This slurry was applied to the surface of a positive electrode current collector made of an aluminum foil having a thickness of 20 ⁇ m by a doctor blade method so that the coating amount after drying was 250 g / m 2 .
  • This positive electrode was dried at 100 ° C. for 2 hours.
  • Specified aluminum silicate dispersion obtained by adding polyvinylidene fluoride as a binder to 15% by mass aqueous dispersion of the specific aluminum silicate (sample A) prepared in Example 1 to 5% by mass with respect to sample A was applied onto the positive electrode sheet by a doctor blade method and vacuum dried at 120 ° C. to prepare a positive electrode A.
  • the amount of sample A applied to the positive electrode A was 5 g / m 2 .
  • the negative electrode was produced by the following method. Artificial graphite powder having an average particle size of 10 ⁇ m was used as the negative electrode active material. Artificial graphite powder and polyvinylidene fluoride were mixed at a mass ratio of 90:10, 1-methyl-2-pyrrolidone was added as an organic solvent, and the mixture was sufficiently kneaded to prepare a negative electrode slurry. This slurry was applied to the surface of a negative electrode current collector made of a copper foil having a thickness of 10 ⁇ m by a doctor blade method so that the coating amount after drying was 75 g / m 2, and dried at 100 ° C. for 2 hours. A negative electrode was produced.
  • a polyethylene porous sheet having a thickness of 25 ⁇ m was used as a separator, and a solution obtained by dissolving LiPF 6 in a mixed solvent of 1: 1 volume ratio of diethyl carbonate and ethylene carbonate to a concentration of 1 mol / l was used as an electrolytic solution.
  • An aluminum laminate cell was produced.
  • An aluminum laminate cell uses a three-layer laminate film made of nylon film-aluminum foil-modified polyolefin film as an exterior material, and the lithium ion secondary in which the positive electrode, negative electrode, separator, electrolyte, etc. are enclosed in the exterior material. It is a battery.
  • the cell with sample A applied to the positive electrode showed similar initial capacity compared to the cell without sample A applied.
  • the battery was charged with a constant current until it reached 4.2 V with a current value of 0.2 C, and then was charged with a constant voltage at 4.2 V until the current value reached 0.01 mA. After standing for 30 minutes after the completion of charging, constant current discharge was performed at a current value of 0.5 C until the lithium ion secondary battery reached 3V.
  • the discharge capacity was measured with the current values of 1C, 2C, 3C, and 5C after charging under the same charging conditions, and the dependence of the discharge capacity on the discharge conditions was evaluated.
  • the cell in which the sample A was applied to the positive electrode had a lower discharge capacity reduction rate than the cell in which the sample A was not applied.
  • the cell in which the sample A was applied to the positive electrode had a smaller rate of increase in impedance after being left for 1 week at 50 ° C. than the cell in which the sample A was not applied.
  • Sample A applied to the positive electrode surface contributes to the extension of cell life and safety. This is presumed to be due to the adsorption of impurities eluted from the positive electrode from the evaluation results of the ion adsorption ability of sample A.

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Abstract

Provided is a positive electrode for lithium ion secondary batteries, which has excellent metal ion adsorbability and excellent metal ion selectivity. A positive electrode for lithium ion secondary batteries of the present invention is provided with an aluminum silicate salt, which has an element molar ratio of Si to Al, namely Si/Al of 0.3 or more but less than 1.0, on the surface.

Description

リチウムイオン二次電池用正極及びそれを用いたリチウムイオン二次電池Positive electrode for lithium ion secondary battery and lithium ion secondary battery using the same
　本発明は、リチウムイオン二次電池用正極及びそれを用いたリチウムイオン二次電池に関する。 The present invention relates to a positive electrode for a lithium ion secondary battery and a lithium ion secondary battery using the same.
　リチウムイオン二次電池は、ニッケル水素電池、鉛蓄電池等の他の二次電池に比べて軽量で、高い入出力特性を有することから、近年、電気自動車、ハイブリッド型電気自動車等に用いられる高入出力用電源として注目されている。 Lithium-ion secondary batteries are lighter and have higher input / output characteristics than other secondary batteries such as nickel metal hydride batteries and lead-acid batteries. It is attracting attention as an output power source.
　しかし、電池の構成材料中に不純物（例えばＦｅ、Ｎｉ、Ｃｕ等の磁性不純物）が存在すると充放電時に負極上に析出してしまう。そして、これらがセパレータを破り正極に到達することで、短絡の原因となる。 However, if impurities (for example, magnetic impurities such as Fe, Ni, Cu, etc.) are present in the constituent materials of the battery, they are deposited on the negative electrode during charge / discharge. These break the separator and reach the positive electrode, causing a short circuit.
　また、リチウムイオン二次電池は、夏場の車中など使用温度が４０℃～８０℃となる場合がある。このとき、正極から正極を構成するＬｉ含有金属酸化物中の金属が溶出し、電池の特性を低下させるという問題がある。このため、不純物の捕捉材の検討や正極の安定化の検討がなされている（例えば、特許文献１参照。）。 Also, the operating temperature of lithium ion secondary batteries may be 40 ° C to 80 ° C, such as in the car in summer. At this time, there is a problem in that the metal in the Li-containing metal oxide constituting the positive electrode is eluted from the positive electrode, and the characteristics of the battery are deteriorated. For this reason, examination of the trap of impurities and examination of the stabilization of the positive electrode have been made (for example, refer to Patent Document 1).
　そこで例えば、非水系リチウムイオン二次電池において、金属元素としてＦｅ又はＭｎを含むリチウム化合物を正極活物質とし、有効細孔径が前記金属元素のイオン半径より大きく０．５ｎｍ（５Å）以下であるゼオライトを前記正極活物質に対して０．５～５ｗｔ％で含有する正極が開示されている（例えば、特許文献２参照）。 Therefore, for example, in a non-aqueous lithium ion secondary battery, a lithium compound containing Fe or Mn as a metal element is used as a positive electrode active material, and the effective pore diameter is larger than the ion radius of the metal element and 0.5 nm (5 mm) or less. Has been disclosed (see, for example, Patent Document 2).
特開２０００－７７１０３号公報JP 2000-77103 A 特開２０１０－１２９４３０号公報JP 2010-129430 A
　しかしながら、既知の吸着剤では不純物を高選択的に吸着できないことや単位質量あたりの吸着能の向上が課題となっていた。 However, known adsorbents have been unable to adsorb impurities with high selectivity and have improved the adsorption capacity per unit mass.
　そこで本発明は、金属イオン吸着性と金属イオン選択性に優れるリチウムイオン二次電池用正極及びそれを用いたリチウムイオン二次電池を提供することを課題とする。 Therefore, an object of the present invention is to provide a positive electrode for a lithium ion secondary battery excellent in metal ion adsorption and metal ion selectivity and a lithium ion secondary battery using the positive electrode.
　前記課題を解決するための具体的手段は以下の通りである。 Specific means for solving the above-mentioned problems are as follows.
＜１＞　集電体と、前記集電体の上に設けられた正極活物質を含有する層とを有し、前記正極活物質を含有する層の表面に、Ｓｉ及びＡｌの元素モル比Ｓｉ／Ａｌが０．３以上１．０未満のアルミニウムケイ酸塩が付与されてなるリチウムイオン二次電池用正極。 <1> A current collector and a layer containing a positive electrode active material provided on the current collector, and an element molar ratio Si of Si and Al on the surface of the layer containing the positive electrode active material / A positive electrode for a lithium ion secondary battery provided with an aluminum silicate having an Al content of 0.3 or more and less than 1.0.
＜２＞　前記アルミニウムケイ酸塩が、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺にピークを有する前記＜１＞に記載のリチウムイオン二次電池用正極。 <2> The positive electrode for a lithium ion secondary battery according to <1>, wherein the aluminum silicate has a peak in the vicinity of 3 ppm in a 27Al-NMR spectrum.
＜３＞　前記アルミニウムケイ酸塩が、２９Ｓｉ－ＮＭＲスペクトルにおいて、－７８ｐｐｍおよび－８５ｐｐｍ近辺にピークを有する前記＜１＞又は＜２＞に記載のリチウムイオン二次電池用正極。 <3> The positive electrode for a lithium ion secondary battery according to <1> or <2>, wherein the aluminum silicate has peaks in the vicinity of −78 ppm and −85 ppm in a 29Si-NMR spectrum.
＜４＞　前記アルミニウムケイ酸塩の前記元素モル比Ｓｉ／Ａｌが０．４以上０．６以下である前記＜１＞～＜３＞のいずれか１項に記載のリチウムイオン二次電池用正極。 <4> The positive electrode for a lithium ion secondary battery according to any one of <1> to <3>, wherein the element molar ratio Si / Al of the aluminum silicate is 0.4 or more and 0.6 or less. .
＜５＞　前記アルミニウムケイ酸塩が、Ｘ線源としてＣｕＫα線を用いた粉末Ｘ線回折スペクトルにおいて２θ＝２６．９°及び４０．３°近辺にピークを有し、層状粘土鉱物に由来する２０°及び３５°近辺にはピークを有しない前記＜１＞～＜４＞のいずれか１項に記載のリチウムイオン二次電池用正極。 <5> The aluminum silicate has peaks in the vicinity of 2θ = 26.9 ° and 40.3 ° in a powder X-ray diffraction spectrum using CuKα ray as an X-ray source, and is derived from a layered clay mineral 20 The positive electrode for a lithium ion secondary battery according to any one of <1> to <4>, wherein the positive electrode has no peak in the vicinity of ° and 35 °.
＜６＞　前記アルミニウムケイ酸塩が、２９Ｓｉ－ＮＭＲスペクトルにおける－７８ｐｐｍ近辺のピークＡと、－８５ｐｐｍ近辺のピークＢとの面積比率（ピークＢ／ピークＡ）が、２．０～９．０である前記＜３＞～＜５＞のいずれか１項に記載のリチウムイオン二次電池用正極。 <6> In the 29Si-NMR spectrum, the aluminum silicate has an area ratio (peak B / peak A) between peak A around -78 ppm and peak B around -85 ppm in the range of 2.0 to 9.0. The positive electrode for a lithium ion secondary battery according to any one of the above items <3> to <5>.
＜７＞　前記アルミニウムケイ酸塩のＢＥＴ比表面積が、２５０ｍ２／ｇ以上である前記＜１＞～＜６＞のいずれか１項に記載のリチウムイオン二次電池用正極。 <7> The positive electrode for a lithium ion secondary battery according to any one of <1> to <6>, wherein the aluminum silicate has a BET specific surface area of 250 m 2 / g or more.
＜８＞　前記アルミニウムケイ酸塩が、前記アルミニウムケイ酸塩を含む分散液によって付与されてなる前記＜１＞～＜７＞のいずれか１項に記載のリチウムイオン二次電池用正極。 <8> The positive electrode for a lithium ion secondary battery according to any one of <1> to <7>, wherein the aluminum silicate is provided by a dispersion containing the aluminum silicate.
＜９＞　前記分散液が更にバインダを含有する前記＜８＞に記載のリチウムイオン二次電池用正極。 <9> The positive electrode for a lithium ion secondary battery according to <8>, wherein the dispersion further contains a binder.
＜１０＞　前記＜１＞～＜９＞のいずれか１項に記載のリチウムイオン二次電池用正極と、
　負極と、
　電解質と、
を有するリチウムイオン二次電池。 <10> The positive electrode for a lithium ion secondary battery according to any one of <1> to <9>,
A negative electrode,
Electrolyte,
A lithium ion secondary battery.
　本明細書は本願の優先権の基礎である日本国特許出願２０１１－２５００４７号の明細書および／または図面に記載される内容を包含する。 This specification includes the contents described in the specification and / or drawings of Japanese Patent Application No. 2011-250047 which is the basis of the priority of the present application.
　本発明によれば、金属イオン吸着性と金属イオン選択性に優れるリチウムイオン二次電池用正極及びこれを用いたリチウムイオン二次電池を提供することができる。 According to the present invention, it is possible to provide a positive electrode for a lithium ion secondary battery excellent in metal ion adsorption and metal ion selectivity and a lithium ion secondary battery using the same.
実施例１及び実施例２に係るアルミニウムケイ酸塩の２７Ａｌ－ＮＭＲスペクトルである。2 is a 27Al-NMR spectrum of an aluminum silicate according to Example 1 and Example 2. FIG. 実施例１及び実施例２に係るアルミニウムケイ酸塩の２９Ｓｉ－ＮＭＲスペクトルである。2 is a 29Si-NMR spectrum of aluminum silicate according to Example 1 and Example 2. FIG. 実施例１に係るアルミニウムケイ酸塩の透過型電子顕微鏡（ＴＥＭ）写真である。2 is a transmission electron microscope (TEM) photograph of aluminum silicate according to Example 1. FIG. 実施例２に係るアルミニウムケイ酸塩の透過型電子顕微鏡（ＴＥＭ）写真である。2 is a transmission electron microscope (TEM) photograph of aluminum silicate according to Example 2. FIG. 本実施形態の一例である、管状のいわゆるイモゴライトを模式的に示す図である。It is a figure which shows typically what is called tubular imogolite which is an example of this embodiment. 実施例１及び実施例２に係るアルミニウムケイ酸塩の粉末Ｘ線回折スペクトルである。2 is a powder X-ray diffraction spectrum of aluminum silicate according to Example 1 and Example 2. FIG.
　本明細書において「工程」との語は、独立した工程だけではなく、他の工程と明確に区別できない場合であってもその工程の所期の作用が達成されれば、本用語に含まれる。また本明細書において「～」を用いて示された数値範囲は、「～」の前後に記載される数値をそれぞれ最小値及び最大値として含む範囲を示す。さらに本明細書において組成物中の各成分の量は、組成物中に各成分に該当する物質が複数存在する場合には、特に断らない限り、組成物中に存在する当該複数の物質の合計量を意味する。 In this specification, the term “process” is not limited to an independent process, and is included in the term if the intended action of the process is achieved even when it cannot be clearly distinguished from other processes. . In the present specification, a numerical range indicated using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively. Further, in this specification, the amount of each component in the composition is the sum of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. Means quantity.
＜リチウムイオン二次電池用正極＞
　本発明のリチウムイオン二次電池用正極は、Ｓｉ及びＡｌの元素モル比Ｓｉ／Ａｌが０．３以上１．０未満のアルミニウムケイ酸塩が表面に付与されてなる。Ｓｉ及びＡｌの元素モル比Ｓｉ／Ａｌが０．３以上１．０未満のアルミニウムケイ酸塩（以下、「特定アルミニウムケイ酸塩」と称する場合がある）は、単位質量あたりに多くの金属イオンの吸着サイトを持ち、高比表面積で金属イオンを高選択的に吸着する特徴を有する。この特定アルミニウムケイ酸塩を正極の表面に付与することで金属イオン吸着性と金属イオン選択性に優れるリチウムイオン二次電池用正極が得られる。また、かかるリチウムイオン二次電池用正極を用いたリチウムイオン二次電池では、短絡の発生が抑制され、寿命特性に優れる。 <Positive electrode for lithium ion secondary battery>
The positive electrode for a lithium ion secondary battery of the present invention is provided with an aluminum silicate having an Si / Al element molar ratio Si / Al of 0.3 or more and less than 1.0 on the surface. An aluminum silicate having an element molar ratio Si / Al of 0.3 to less than 1.0 (hereinafter sometimes referred to as “specific aluminum silicate”) has many metal ions per unit mass. And has a feature of highly selectively adsorbing metal ions with a high specific surface area. By applying this specific aluminum silicate to the surface of the positive electrode, a positive electrode for a lithium ion secondary battery excellent in metal ion adsorption and metal ion selectivity can be obtained. Moreover, in the lithium ion secondary battery using such a positive electrode for a lithium ion secondary battery, the occurrence of a short circuit is suppressed and the life characteristics are excellent.
　特定アルミニウムケイ酸塩は、ＳｉとＡｌの酸化物塩でありその価数が異なるため、ＯＨ基が多く存在し、これがイオン交換能を有している。したがって、単位質量あたりに多くの金属イオンの吸着サイトを持ち、高比表面積で金属イオンを高選択的に吸着する特徴を有する。特に、特定アルミニウムケイ酸塩は、リチウムイオン電池の充放電に必須なリチウムイオンを殆ど吸着しないにもかかわらず、不要な金属イオンを吸着するという特異的な性質を有する。なお、本発明において不要な金属イオンとは、リチウムイオン以外のニッケルイオン、マンガンイオン、銅イオンなどをいう。これらの不要な金属イオンは、電池の構成材料中に存在する不純物イオンや、高温下で正極から溶出する金属イオンに由来する。 Specified aluminum silicate is an oxide salt of Si and Al and has different valences, so there are many OH groups, and this has ion exchange ability. Therefore, it has a feature of having many metal ion adsorption sites per unit mass and highly selectively adsorbing metal ions with a high specific surface area. In particular, the specific aluminum silicate has a specific property of adsorbing unnecessary metal ions even though it hardly adsorbs lithium ions essential for charging and discharging of a lithium ion battery. In the present invention, unnecessary metal ions refer to nickel ions other than lithium ions, manganese ions, copper ions, and the like. These unnecessary metal ions are derived from impurity ions present in the constituent materials of the battery and metal ions eluted from the positive electrode at a high temperature.
　また、特定アルミニウムケイ酸塩は無機酸化物であるため、熱安定性や、溶剤中での安定性に優れている。このため充放電中でも安定に存在できる。 Moreover, since the specific aluminum silicate is an inorganic oxide, it has excellent thermal stability and stability in a solvent. For this reason, it can exist stably even during charging and discharging.
　この特定アルミニウムケイ酸塩をリチウムイオン二次電池の正極の表面に付与することで、電池中の不要な金属イオンが特定アルミニウムケイ酸塩に吸着されるため、電池中での不要な特定の金属イオンの濃度上昇を選択的に抑制することが可能となる。かかるリチウムイオン二次電池用正極を用いたリチウムイオン二次電池では、短絡の発生が抑制され、寿命特性に優れる。 By applying this specific aluminum silicate to the surface of the positive electrode of the lithium ion secondary battery, unnecessary metal ions in the battery are adsorbed on the specific aluminum silicate. It is possible to selectively suppress an increase in ion concentration. In a lithium ion secondary battery using such a positive electrode for a lithium ion secondary battery, the occurrence of a short circuit is suppressed and the life characteristics are excellent.
　特に不純物イオンは正極でイオン化すること、及び電池の使用温度が高いと正極から金属イオンが溶出することから、特定アルミニウムケイ酸塩は正極の表面に付与することが、短絡を防止しつつ正極活物質間の導電性を保持する観点から効果的である。 In particular, impurity ions are ionized at the positive electrode, and metal ions are eluted from the positive electrode when the operating temperature of the battery is high. This is effective from the viewpoint of maintaining conductivity between substances.
　以下では、特定アルミニウムケイ酸塩について詳細に説明する。 In the following, the specific aluminum silicate will be described in detail.
（アルミニウムケイ酸塩）
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着能及び金属イオン選択性の観点から、Ｓｉ及びＡｌの元素比Ｓｉ／Ａｌがモル比で０．３以上１．０未満であり、０．４以上０．６以下であることが好ましく、０．４５以上０．５５以下であることがより好ましい。Ｓｉ／Ａｌがモル比で０．３未満の場合には、金属イオンの吸着能向上に寄与しないＡｌの量が過剰となり、不純物のイオン吸着能が乏しい。１．０以上では、金属イオンの選択性向上に寄与しないＳｉの量が過剰になりやすく、金属イオン選択性が低下する。 (Aluminum silicate)
In the specific aluminum silicate according to this embodiment, the element ratio Si / Al between Si and Al is 0.3 or more and less than 1.0 in terms of metal ion adsorption ability and metal ion selectivity. It is preferably 4 or more and 0.6 or less, and more preferably 0.45 or more and 0.55 or less. When the Si / Al molar ratio is less than 0.3, the amount of Al that does not contribute to the enhancement of metal ion adsorption capacity becomes excessive, and the ion adsorption capacity of impurities is poor. If it is 1.0 or more, the amount of Si that does not contribute to the improvement of metal ion selectivity tends to be excessive, and the metal ion selectivity is lowered.
　Ｓｉ及びＡｌの元素比Ｓｉ／Ａｌは、ＩＣＰ発光分光装置（例えば、日立製作所社製ＩＣＰ発光分光装置：Ｐ－４０１０）を用いて、常法により測定できる。 The element ratio Si / Al of Si and Al can be measured by an ordinary method using an ICP emission spectrometer (for example, ICP emission spectrometer: P-4010 manufactured by Hitachi, Ltd.).
　本実施形態に係る特定アルミニウムケイ酸塩は、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺にピークを有することが好ましい。２７Ａｌ－ＮＭＲ測定装置としては、例えば、ブルカー・バイオスピン製ＡＶ４００ＷＢ型を用いることができ、具体的な測定条件は以下の通りである。 The specific aluminum silicate according to the present embodiment preferably has a peak in the vicinity of 3 ppm in the 27Al-NMR spectrum. As the 27Al-NMR measuring apparatus, for example, AV400WB type manufactured by Bruker BioSpin can be used, and specific measuring conditions are as follows.
　共鳴周波数：１０４ＭＨｚ
　測定方法：ＭＡＳ（シングルパルス）
　ＭＡＳ回転数：１０ｋＨｚ
　測定領域：５２ｋＨｚ
　データポイント数：４０９６
　ｒｅｓｏｌｕｔｉｏｎ（測定領域／データポイント数）：１２．７Ｈｚ
　パルス幅：３．０μｓｅｃ
　遅延時間：２秒
　化学シフト値基準：α－アルミナを３．９４ｐｐｍ
　ｗｉｎｄｏｗ関数：指数関数
　Ｌｉｎｅ　Ｂｒｏａｄｅｎｉｎｇ係数：１０Ｈｚ
　図１に、本実施形態に係る特定アルミニウムケイ酸塩の一例として、後述の実施例１及び実施例２に係る特定アルミニウムケイ酸塩の２７Ａｌ－ＮＭＲスペクトルを示す。 Resonance frequency: 104MHz
Measuring method: MAS (single pulse)
MAS rotation speed: 10 kHz
Measurement area: 52 kHz
Number of data points: 4096
resolution (measurement area / number of data points): 12.7 Hz
Pulse width: 3.0 μsec
Delay time: 2 seconds Chemical shift value standard: 3.94 ppm of α-alumina
window function: exponential function Line Broadening coefficient: 10 Hz
FIG. 1 shows a 27Al-NMR spectrum of a specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
　図１に示すように、本実施形態に係る特定アルミニウムケイ酸塩は、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺にピークを有することが好ましい。３ｐｐｍ近辺のピークは、６配位のＡｌに由来するピークであると推定される。更に、５５ｐｐｍ付近にピークを有していてもよい。５５ｐｐｍ付近のピークは、４配位のＡｌに由来するピークであると推定される。 As shown in FIG. 1, the specific aluminum silicate according to this embodiment preferably has a peak in the vicinity of 3 ppm in the 27Al-NMR spectrum. The peak around 3 ppm is estimated to be a peak derived from 6-coordinated Al. Furthermore, you may have a peak around 55 ppm. The peak near 55 ppm is estimated to be a peak derived from tetracoordinated Al.
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着性と金属イオン選択性の観点から、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺のピークに対する、５５ｐｍ付近のピークの面積比率が、２５％以下であることが好ましく、２０％以下であることがより好ましく、１５％以下であることが更に好ましい。 In the specific aluminum silicate according to the present embodiment, from the viewpoint of metal ion adsorption and metal ion selectivity, the area ratio of the peak near 55 pm to the peak near 3 ppm in the 27Al-NMR spectrum is 25% or less. Preferably, it is 20% or less, more preferably 15% or less.
　また、本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着性と金属イオン選択性の観点から、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺のピークに対する、５５ｐｍ付近のピークの面積比率は、１％以上であることが好ましく、５％以上であることがより好ましく、１０％以上であることが更に好ましい。 In addition, the specific aluminum silicate according to the present embodiment has an area ratio of a peak near 55 pm to a peak near 3 ppm in the 27Al-NMR spectrum from the viewpoint of metal ion adsorptivity and metal ion selectivity of 1%. Preferably, it is preferably 5% or more, more preferably 10% or more.
　本実施形態に係る特定アルミニウムケイ酸塩は、２９Ｓｉ－ＮＭＲスペクトルにおいて、－７８ｐｐｍ近辺および－８５ｐｐｍ近辺にピークを有することが好ましい。かかる特定の２９Ｓｉ－ＮＭＲスペクトルを示すアルミニウムケイ酸塩は、金属イオン吸着性と金属イオン選択性により優れる。 The specific aluminum silicate according to this embodiment preferably has peaks in the vicinity of −78 ppm and in the vicinity of −85 ppm in the 29Si-NMR spectrum. Aluminum silicate showing such a specific 29Si-NMR spectrum is excellent in metal ion adsorption and metal ion selectivity.
　２９Ｓｉ－ＮＭＲスペクトルを測定するための２９Ｓｉ－ＮＭＲ測定装置としては、例えば、ブルカー・バイオスピン製ＡＶ４００ＷＢ型を用いることができ、具体的な測定条件は以下の通りである。 As a 29Si-NMR measuring apparatus for measuring a 29Si-NMR spectrum, for example, an AV400WB type manufactured by Bruker BioSpin can be used, and specific measurement conditions are as follows.
　共鳴周波数：７９．５ＭＨｚ
　測定方法：ＭＡＳ（シングルパルス）
　ＭＡＳ回転数：６ｋＨｚ
　測定領域：２４ｋＨｚ
　データポイント数：２０４８
　ｒｅｓｏｌｕｔｉｏｎ（測定領域／データポイント数）：５．８Ｈｚ
　パルス幅：４．７μｓｅｃ
　遅延時間：６００秒
　化学シフト値基準：ＴＭＳＰ－ｄ４（３－（トリメチルシリル）（２，２，３，３－２Ｈ４）プロピオン酸ナトリウム）を１．５２ｐｐｍ
　ｗｉｎｄｏｗ関数：指数関数
　Ｌｉｎｅ　Ｂｒｏａｄｅｎｉｎｇ係数：５０Ｈｚ
　図２に、本実施形態に係る特定アルミニウムケイ酸塩の一例として、後述の実施例１及び実施例２に係る特定アルミニウムケイ酸塩の２９Ｓｉ－ＮＭＲスペクトルを示す。 Resonance frequency: 79.5 MHz
Measuring method: MAS (single pulse)
MAS rotation speed: 6 kHz
Measurement area: 24 kHz
Number of data points: 2048
resolution (measurement area / number of data points): 5.8 Hz
Pulse width: 4.7 μsec
Delay time: 600 seconds Chemical shift value criteria: TMSP-d4 (3- (trimethylsilyl) (2,2,3,3-2H4) sodium propionate) 1.52 ppm
window function: exponential function Line Broadening coefficient: 50 Hz
FIG. 2 shows 29Si-NMR spectra of specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
　図２に示すように、本実施形態に係る特定アルミニウムケイ酸塩は、２９Ｓｉ－ＮＭＲスペクトルにおいて、－７８ｐｐｍ近辺および－８５ｐｐｍ近辺にピークを有することが好ましい。－７８ｐｐｍ近辺に現れるピークＡは、イモゴライト・アロフェン類など結晶構造の特定アルミニウムケイ酸塩に由来し、ＨＯ－Ｓｉ－（ＯＡｌ）３という構造に起因すると考えられる。 As shown in FIG. 2, the specific aluminum silicate according to this embodiment preferably has peaks in the vicinity of −78 ppm and in the vicinity of −85 ppm in the 29Si-NMR spectrum. The peak A that appears in the vicinity of −78 ppm is derived from a specific aluminum silicate having a crystal structure such as imogolite and allophanes, and is considered to be caused by a structure of HO—Si— (OAl) 3.
　また－８５ｐｐｍ近辺に現れるピークＢは、粘土構造の特定アルミニウムケイ酸塩又は非晶質構造の特定アルミニウムケイ酸塩と考えられる。したがって、７８ｐｐｍ近辺および－８５ｐｐｍ近辺にピークを有する特定アルミニウムケイ酸塩は、結晶構造の特定アルミニウムケイ酸塩と、粘度構造又は非晶質構造の特定アルミニウムケイ酸塩との混合物又は複合体であると推定される。 Further, the peak B appearing around −85 ppm is considered to be a specific aluminum silicate having a clay structure or a specific aluminum silicate having an amorphous structure. Therefore, the specific aluminum silicate having peaks near 78 ppm and -85 ppm is a mixture or composite of the specific aluminum silicate having a crystal structure and the specific aluminum silicate having a viscosity structure or an amorphous structure. It is estimated to be.
　特に－７８ｐｐｍ近辺に現れるピークＡを有するアルミニウムケイ酸塩は、単位質量あたりにＯＨ基が多く存在する。このため－７８ｐｐｍ近辺に現れるピークＡを有するアルミニウムケイ酸塩は、水分吸着能に優れていることは知見されていた。これに対して発明者らは、このアルミニウムケイ酸塩が金属イオン吸着能にすぐれ、特に電池に悪影響を与える金属イオンを選択的に吸着することを新たに見出した。このため、この特定アルミニウムケイ酸塩を含むリチウムイオン電池では短絡の発生が著しく少なくなり、結果として寿命特性に優れると考えることができる。 In particular, aluminum silicate having a peak A that appears in the vicinity of −78 ppm has many OH groups per unit mass. For this reason, it has been found that the aluminum silicate having the peak A that appears in the vicinity of −78 ppm is excellent in water adsorption ability. On the other hand, the inventors have newly found that this aluminum silicate has an excellent ability to adsorb metal ions, and in particular selectively adsorbs metal ions which adversely affect the battery. For this reason, in the lithium ion battery containing this specific aluminum silicate, the occurrence of short circuit is remarkably reduced, and as a result, it can be considered that the life characteristics are excellent.
　なお、本実施形態に係る特定アルミニウムケイ酸塩は、層状粘土鉱物に由来する－１１０ｐｐｍ近辺のピークを有さなくてもよい。ここでピークを有さないとは、－１１０ｐｐｍ付近におけるベースラインからの変位がノイズレベル以下であることを意味する。 Note that the specific aluminum silicate according to this embodiment may not have a peak around −110 ppm derived from the layered clay mineral. Here, having no peak means that the displacement from the baseline in the vicinity of −110 ppm is below the noise level.
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着能及び金属イオン選択性が向上する観点から、２９Ｓｉ－ＮＭＲスペクトルにおける－７８ｐｐｍ近辺のピークＡと、－８５ｐｐｍ近辺のピークＢの面積比率（ピークＢ／ピークＡ）が、０．４～９．０であることが好ましく、１．５～９．０であることがより好ましく、２．０～９．０であることが更に好ましく、２．０～７．０であることが更に好ましく、２．０～５．０であることが更に好ましく、２．０～４．０であることが特に好ましい。 The specific aluminum silicate according to this embodiment has an area ratio of a peak A around −78 ppm and a peak B around −85 ppm in the 29Si-NMR spectrum (from the viewpoint of improving metal ion adsorption ability and metal ion selectivity). Peak B / Peak A) is preferably 0.4 to 9.0, more preferably 1.5 to 9.0, still more preferably 2.0 to 9.0. It is more preferably 0.0 to 7.0, still more preferably 2.0 to 5.0, and particularly preferably 2.0 to 4.0.
　２９Ｓｉ－ＮＭＲスペクトルにおける前記ピークの面積比率を求める際には、まず２９Ｓｉ－ＮＭＲスペクトルにおいてベースラインを引く。図２では、－５５ｐｐｍと－１４０ｐｐｍとを結んだ直線をベースラインとする。 When calculating the area ratio of the peak in the 29Si-NMR spectrum, a baseline is first drawn in the 29Si-NMR spectrum. In FIG. 2, a straight line connecting -55 ppm and -140 ppm is taken as a baseline.
　次に、－７８ｐｐｍ近辺に現れるピークＡと－８５ｐｐｍ近辺のピークＢとの谷に当たる化学シフト値（図２では、－８１ｐｐｍ付近）で区切る。 Next, it is divided by a chemical shift value (in the vicinity of −81 ppm in FIG. 2) corresponding to the valley between the peak A appearing near −78 ppm and the peak B near −85 ppm.
　－７８ｐｐｍ近辺のピークＡの面積は、図２においては化学シフト軸と直行し－８１ｐｐｍを通る直線と上記ベースラインに囲まれた領域の面積であり、ピークＢの面積は、－８１ｐｐｍを通り化学シフト軸と直行する直線と上記ベースラインに囲まれた領域の面積である。 In FIG. 2, the area of peak A near −78 ppm is the area of the region surrounded by the straight line passing through −81 ppm perpendicular to the chemical shift axis and the base line, and the area of peak B is chemical through −81 ppm. This is the area of a region surrounded by a straight line perpendicular to the shift axis and the base line.
　なお、上記各ピークの面積は、ＮＭＲ測定装置に組み込まれた解析ソフトにより求めてもよい。 In addition, you may obtain | require the area of each said peak with the analysis software integrated in the NMR measuring apparatus.
　図３及び図４に、本実施形態に係る特定アルミニウムケイ酸塩の透過型電子顕微鏡（ＴＥＭ）写真の一例を示す。図３に示す特定アルミニウムケイ酸塩は、後述の実施例１に係る特定アルミニウムケイ酸塩である。図４に示す特定アルミニウムケイ酸塩は、後述の実施例２に係る特定アルミニウムケイ酸塩である。 3 and 4 show an example of a transmission electron microscope (TEM) photograph of the specific aluminum silicate according to the present embodiment. The specific aluminum silicate shown in FIG. 3 is a specific aluminum silicate according to Example 1 described later. The specific aluminum silicate shown in FIG. 4 is a specific aluminum silicate according to Example 2 described later.
　図３に示されるように、実施例１に係る特定アルミニウムケイ酸塩は、透過型電子顕微鏡（ＴＥＭ）において１００，０００倍で観察したときに、長さ５０ｎｍ以上の管状物が存在していない。実施例２に係る特定アルミニウムケイ酸塩は、図４に示されるように、管状のいわゆるイモゴライトである。 As shown in FIG. 3, the specific aluminum silicate according to Example 1 does not have a tubular product having a length of 50 nm or more when observed at a magnification of 100,000 with a transmission electron microscope (TEM). . The specific aluminum silicate according to Example 2 is tubular so-called imogolite, as shown in FIG.
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着能と金属イオン選択性の観点から、透過型電子顕微鏡（ＴＥＭ）において１００，０００倍で観察したときに、長さ５０ｎｍ以上の管状物が存在していないことが好ましい。 The specific aluminum silicate according to the present embodiment is a tubular product having a length of 50 nm or more when observed with a transmission electron microscope (TEM) at a magnification of 100,000 from the viewpoint of metal ion adsorption ability and metal ion selectivity. Is preferably absent.
　特定アルミニウムケイ酸塩の透過型電子顕微鏡（ＴＥＭ）の観察は、１００ｋＶの加速電圧で行う。また観察試料としては、後述する製造方法における第二洗浄工程（脱塩及び固体分離）前の加熱後溶液をＴＥＭ観察試料調製用の支持体上に滴下し、次いで乾燥して薄膜としたものを用いる。尚、ＴＥＭ画像のコントラストが充分に得られない場合には、コントラストが充分に得られるように加熱処理後の溶液を適宜希釈したものを用いて観察試料を調製する。 Observation of a specific aluminum silicate with a transmission electron microscope (TEM) is performed at an acceleration voltage of 100 kV. In addition, as an observation sample, a solution after heating before the second washing step (desalting and solid separation) in the manufacturing method described later is dropped on a support for preparing a TEM observation sample, and then dried to form a thin film. Use. When the contrast of the TEM image cannot be obtained sufficiently, an observation sample is prepared using an appropriately diluted solution after the heat treatment so that a sufficient contrast can be obtained.
　図４に示されるような管状物は、後述の特定アルミニウムケイ酸塩の製造方法において、ケイ酸イオン及びアルミニウムイオンを特定の濃度以下で加熱処理を実施することで製造される。他方、図３に示されるような管状物が観察されない特定アルミニウムケイ酸塩は、ケイ酸イオン及びアルミニウムイオンを特定の濃度以上で加熱処理を実施することで製造される。 4 is manufactured by performing a heat treatment of silicate ions and aluminum ions at a specific concentration or less in a method for manufacturing a specific aluminum silicate described later. On the other hand, the specific aluminum silicate in which a tubular product as shown in FIG. 3 is not observed is manufactured by performing a heat treatment of silicate ions and aluminum ions at a specific concentration or more.
　図５は、本実施形態に係る特定アルミニウムケイ酸塩の一例である、管状のいわゆるイモゴライト（後述の製造方法で説明する第一の特定アルミニウムケイ酸塩）１０を模式的に示す図面である。図５に示すように、管状体１０ａ同士により繊維構造が形成される傾向があり、管状体１０ａの筒内の内壁２０や、管状体１０ａ 間の隙間３０を形成する管状体１０ａの外壁（外周面）を金属イオンの吸着サイトとして利用できる。管状体１０ａの管部長さ方向の長さは、例えば１ｎｍ～１０μｍである。管状体１０ａは、例えば円管状を呈しており、外径は例えば１．５ｎｍ～３．０ｎｍであり、内径は例えば０．７ｎｍ～１．４ｎｍである。 FIG. 5 is a drawing schematically showing a tubular so-called imogolite (first specific aluminum silicate described in a manufacturing method described later) 10 which is an example of the specific aluminum silicate according to the present embodiment. As shown in FIG. 5, the fiber structure tends to be formed by the tubular bodies 10 a, and the outer wall (outer periphery) of the tubular body 10 a forming the inner wall 20 in the tube of the tubular body 10 a and the gap 30 between the tubular body 10 a ridges. Surface) can be used as an adsorption site for metal ions. The length of the tubular body 10a in the tube portion length direction is, for example, 1 nm to 10 μm. The tubular body 10a has, for example, a circular tubular shape, and has an outer diameter of, for example, 1.5 nm to 3.0 nm and an inner diameter of, for example, 0.7 nm to 1.4 nm.
　なお、管状特定アルミニウムケイ酸塩であるいわゆるイモゴライトの繊維が透過型電子顕微鏡（ＴＥＭ）写真で観察される場合には、２９Ｓｉ－ＮＭＲスペクトルにおいて、前記ピークＢの面積が小さくなる方向にある。 When the so-called imogolite fiber, which is a tubular specific aluminum silicate, is observed with a transmission electron microscope (TEM) photograph, the area of the peak B tends to decrease in the 29Si-NMR spectrum.
　本実施形態に係る特定アルミニウムケイ酸塩は、Ｘ線源としてＣｕＫα線を用いた粉末Ｘ線回折スペクトルにおいて、２θ＝２６．９°及び４０．３°近辺にピークを有することが好ましい。粉末Ｘ線回折は、Ｘ線源としてＣｕＫα線を用いて測定される。例えば、リガク社製：Ｇｅｉｇｅｒｆｌｅｘ　ＲＡＤ－２Ｘ（商品名）の粉末Ｘ線回折装置を用いることができる。 The specific aluminum silicate according to this embodiment preferably has peaks in the vicinity of 2θ = 26.9 ° and 40.3 ° in a powder X-ray diffraction spectrum using CuKα rays as an X-ray source. Powder X-ray diffraction is measured using CuKα rays as an X-ray source. For example, a powder X-ray diffractometer manufactured by Rigaku Corporation: Geigerflex RAD-2X (trade name) can be used.
　図６に、本実施形態に係る特定アルミニウムケイ酸塩の一例として、後述の実施例１及び実施例２に係る特定アルミニウムケイ酸塩の粉末Ｘ線回折スペクトルを示す。 FIG. 6 shows a powder X-ray diffraction spectrum of the specific aluminum silicate according to Example 1 and Example 2 described later as an example of the specific aluminum silicate according to the present embodiment.
　図６に示すように、本実施形態に係る特定アルミニウムケイ酸塩は、粉末Ｘ線回折スペクトルにおいて、２θ＝２６．９°、４０．３°近辺にピークを有する。２θ＝２６．９°及び４０．３°近辺のピークは、アルミニウムケイ酸塩に由来するピークと推定される。 As shown in FIG. 6, the specific aluminum silicate according to this embodiment has a peak in the vicinity of 2θ = 26.9 °, 40.3 ° in the powder X-ray diffraction spectrum. The peaks around 2θ = 26.9 ° and 40.3 ° are presumed to be peaks derived from aluminum silicate.
　なお、本実施形態に係る特定アルミニウムケイ酸塩は、粉末Ｘ線回折スペクトルにおいて、２θ＝２０°及び３５°近辺にブロードなピークを有さなくてもよい。２θ＝２０°及び３５°近辺のピークは、層状の粘土鉱物のｈｋ０面の反射から得られるピークと考えられる。 Note that the specific aluminum silicate according to the present embodiment may not have broad peaks in the vicinity of 2θ = 20 ° and 35 ° in the powder X-ray diffraction spectrum. The peaks around 2θ = 20 ° and 35 ° are considered to be peaks obtained from reflection of the hk0 plane of the layered clay mineral.
　ここでピークを有さないとは、２θ＝２０°及び３５°近辺におけるベースラインからの変位がノイズレベル以下であることを意味し、具体的にはベースラインから変位がノイズ幅の１００％以下であることを意味する。 Here, having no peak means that the displacement from the baseline in the vicinity of 2θ = 20 ° and 35 ° is less than the noise level, specifically, the displacement from the baseline is less than 100% of the noise width. It means that.
　更に、実施例１に係る特定アルミニウムケイ酸塩のように、本実施形態の特定アルミニウムケイ酸塩は、２θ＝１８．８°、２０．３°、２７．８°、４０．６°及び５３．３°近辺にピークを有してもよい。２θ＝１８．８°、２０．３°、２７．８°、４０．６°及び５３．３°近辺のピークは、副生物である水酸化アルミニウムに由来するピークと推定される。なお、後述の特定アルミニウムケイ酸塩の製造方法において、加熱処理時の加熱温度を１６０℃以下とすることで水酸化アルミニウムの析出を抑えることができる。また、遠心分離による脱塩処理時のｐＨを調整することによって、水酸化アルミニウムの含有量を調整することができる。 Furthermore, like the specific aluminum silicate according to Example 1, the specific aluminum silicate of this embodiment has 2θ = 18.8 °, 20.3 °, 27.8 °, 40.6 ° and 53 It may have a peak around 3 °. The peaks around 2θ = 18.8 °, 20.3 °, 27.8 °, 40.6 °, and 53.3 ° are presumed to be peaks derived from by-product aluminum hydroxide. In addition, in the manufacturing method of the specific aluminum silicate mentioned later, precipitation of aluminum hydroxide can be suppressed by making the heating temperature at the time of heat processing into 160 degrees C or less. Moreover, content of aluminum hydroxide can be adjusted by adjusting pH at the time of the desalting process by centrifugation.
　また、実施例２に係る特定アルミニウムケイ酸塩のように、本実施形態の特定アルミニウムケイ酸塩は、２θ＝４．８°、９．７°及び１４．０°近辺にピークを有してもよい。更に、２θ＝１８．３°近辺にピークを有していてもよい。２θ＝４．８°、９．７°、１４．０°及び１８．３°近辺のピークは、筒状特定アルミニウムケイ酸塩であるいわゆるイモゴライトの単繊維が平行に凝集して束状構造をとっていることに由来するピークと推定される。 Moreover, like the specific aluminum silicate which concerns on Example 2, the specific aluminum silicate of this embodiment has a peak in the vicinity of 2θ = 4.8 °, 9.7 ° and 14.0 °. Also good. Further, it may have a peak in the vicinity of 2θ = 18.3 °. The peaks around 2θ = 4.8 °, 9.7 °, 14.0 °, and 18.3 ° show a bundle structure in which single fibers of so-called imogolite, which is a cylindrical specific aluminum silicate, aggregate in parallel. It is presumed to be a peak derived from taking it.
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオン吸着能が向上する観点から、ＢＥＴ比表面積が２５０ｍ２／ｇ以上であることが好ましく、２８０ｍ２／ｇ以上であることがより好ましく、３００ｍ２／ｇ以上であることが更に好ましい。ＢＥＴ比表面積が２５０ｍ２／ｇ以上であると、単位質量あたりの不純物イオンや溶出イオン吸着量が大きくなるため効率がよく、少量で高い効果が得られる。 The specific aluminum silicate according to this embodiment has a BET specific surface area of preferably 250 m 2 / g or more, more preferably 280 m 2 / g or more, and 300 m from the viewpoint of improving the metal ion adsorption ability. More preferably, it is 2 / g or more. When the BET specific surface area is 250 m 2 / g or more, the adsorbed amount of impurity ions and eluted ions per unit mass is increased, so that the efficiency is good and a high effect is obtained with a small amount.
　また、ＢＥＴ比表面積の上限値は特に制限が無いが、比表面積が大きすぎると単位質量当たりの空気中の水分吸着量が多くなってしまうため、ＢＥＴ比表面積は１５００ｍ２／ｇ以下であることが好ましく、１２００ｍ２／ｇ以下であることがより好ましく、１０００ｍ２／ｇ以下であることが更に好ましい。 The upper limit of the BET specific surface area is not particularly limited, but if the specific surface area is too large, the amount of moisture adsorbed in the air per unit mass will increase, so the BET specific surface area should be 1500 m 2 / g or less. Is preferably 1200 m 2 / g or less, more preferably 1000 m 2 / g or less.
　特定アルミニウムケイ酸塩のＢＥＴ比表面積は、ＪＩＳ　Ｚ　８８３０に準じて７７Ｋでの窒素吸着能から測定する。評価装置としては、例えば、ＱＵＡＮＴＡＣＨＲＯＭＥ社製：ＡＵＴＯＳＯＲＢ－１（商品名）などを用いることができる。ＢＥＴ比表面積の測定を行う際には、試料表面及び構造中に吸着している水分がガス吸着能に影響を及ぼすと考えられることから、まず、加熱による水分除去の前処理を行う。 The BET specific surface area of the specific aluminum silicate is measured from the nitrogen adsorption ability at 77K according to JIS Z 8830. As the evaluation apparatus, for example, AUTOSORB-1 (trade name) manufactured by QUANTACHROME can be used. When measuring the BET specific surface area, it is considered that the moisture adsorbed on the sample surface and the structure affects the gas adsorption capacity. Therefore, pretreatment for removing moisture by heating is first performed.
　前記前処理では、０．０５ｇの測定試料を投入した測定用セルを、真空ポンプで１０Ｐａ以下に減圧した後、１１０℃で加熱し、３時間以上保持した後、減圧した状態を保ったまま常温（２５℃）まで自然冷却する。この前処理を行った後、評価温度を７７Ｋとし、評価圧力範囲を相対圧（飽和蒸気圧に対する平衡圧力）にて１未満として測定する。 In the pretreatment, the measurement cell charged with 0.05 g of the measurement sample is depressurized to 10 Pa or less with a vacuum pump, heated at 110 ° C., held for 3 hours or more, and kept at a normal temperature while maintaining the depressurized state. Cool naturally to (25 ° C). After performing this pretreatment, the evaluation temperature is 77K, and the evaluation pressure range is measured as a relative pressure (equilibrium pressure with respect to saturated vapor pressure) of less than 1.
　本実施形態に係る特定アルミニウムケイ酸塩は、金属イオンの吸着能が向上する観点から、全細孔容積が０．１ｃｍ３／ｇ以上であることが好ましく、０．１２ｃｍ３／ｇ以上であることがより好ましく、０．１５ｃｍ３／ｇ以上であることが更に好ましい。また、全細孔容積の上限値は特に制限が無いが、全細孔容積が大きすぎると単位質量当たりの空気中の水分吸着量が多くなってしまうため、全細孔容積は１．５ｃｍ３／ｇ以下であることが好ましく、１．２ｃｍ３／ｇ以下であることがより好ましく、１．０ｃｍ３／ｇ以下であることが更に好ましい。 Certain aluminum silicates according to the present embodiment, from the viewpoint of improving the adsorption capacity of the metal ion, is preferably, 0.12 cm 3 / g or more that the total pore volume is 0.1 cm 3 / g or more More preferably, it is still more preferably 0.15 cm 3 / g or more. The upper limit of the total pore volume is not particularly limited, but if the total pore volume is too large, the amount of moisture adsorbed in the air per unit mass increases, so the total pore volume is 1.5 cm 3. / G or less is preferable, 1.2 cm 3 / g or less is more preferable, and 1.0 cm 3 / g or less is still more preferable.
　特定アルミニウムケイ酸塩の全細孔容積は、前記ＢＥＴ比表面積に基づき、相対圧が０．９５以上１未満の範囲で得られたデータの中、相対圧１に最も近いガス吸着量を液体に換算して求める。 The total pore volume of the specific aluminum silicate is based on the BET specific surface area. Among the data obtained in the range where the relative pressure is 0.95 or more and less than 1, the gas adsorption amount closest to the relative pressure 1 is set to the liquid. Calculate by conversion.
　不純物イオンのイオン半径が０．０１ｎｍ～０．１ｎｍ程度であるため、本実施形態に係る特定アルミニウムケイ酸塩の平均細孔直径は１．５ｎｍ以上であることが好ましく、この不純物イオンは配位子を伴った状態で吸着するサイトまで移動するため、２．０ｎｍ以上であることがさらに好ましい。また、平均細孔直径の上限値は特に制限が無いが、平均細孔直径が大きい場合、比表面積を低下させてしまうことから、５０ｎｍ以下であることが好ましく、２０ｎｍ以下であることがより好ましく、５．０ｎｍ以下であることが更に好ましい。 Since the ion radius of the impurity ions is about 0.01 nm to 0.1 nm, the average pore diameter of the specific aluminum silicate according to this embodiment is preferably 1.5 nm or more. Since it moves to the site | part which adsorb | sucks in the state with a child, it is more preferable that it is 2.0 nm or more. Further, the upper limit value of the average pore diameter is not particularly limited, but when the average pore diameter is large, the specific surface area is decreased, so that it is preferably 50 nm or less, and more preferably 20 nm or less. More preferably, it is 5.0 nm or less.
　特定アルミニウムケイ酸塩の平均細孔直径は、前記ＢＥＴ比表面積及び全細孔容積に基づき、全細孔を１つの円筒形細孔で構成されていると仮定して求める。 The average pore diameter of the specific aluminum silicate is obtained on the basis of the BET specific surface area and the total pore volume, assuming that all the pores are composed of one cylindrical pore.
　本実施形態に係る特定アルミニウムケイ酸塩は、水分含有率が１０質量％以下であることが好ましく、５質量％以下であることがより好ましい。水分含有率が１０質量％以下であることでリチウムイオン二次電池を構成した場合に、水分が電気分解を起こすことに起因するガスの発生を抑制することができ、電池膨張を抑制できる。 The specific aluminum silicate according to this embodiment preferably has a moisture content of 10% by mass or less, and more preferably 5% by mass or less. When a lithium ion secondary battery is constituted by having a water content of 10% by mass or less, generation of gas due to water causing electrolysis can be suppressed, and battery expansion can be suppressed.
　なお、水分含有率はカールフィッシャー法にて測定することができる。 The water content can be measured by the Karl Fischer method.
　特定アルミニウムケイ酸塩の水分含有率を１０質量％以下とする方法としては、通常用いられる乾燥方法を特に制限無く適用することができる。例えば、大気圧下で、１００℃～３００℃程度、６時間～２４時間程度の間、乾燥処理する方法が挙げられる。 As a method for setting the moisture content of the specific aluminum silicate to 10% by mass or less, a commonly used drying method can be applied without any particular limitation. For example, a method of drying at about 100 ° C. to 300 ° C. for about 6 hours to 24 hours under atmospheric pressure can be mentioned.
（特定アルミニウムケイ酸塩の製造方法）
　本発明に係る特定アルミニウムケイ酸塩の製造方法は、（ａ）ケイ酸イオンを含む溶液及びアルミニウムイオンを含む溶液を混合して反応生成物を得る工程と、（ｂ）前記反応生成物を、脱塩及び固体分離する工程と、（ｃ）前記工程（ｂ）で固体分離されたものを水性媒体中、酸の存在下で加熱処理する工程と、（ｄ）前記工程（ｃ）で加熱処理して得られたものを、脱塩及び固体分離する工程と、を有し、必要に応じてその他の工程を有して構成される。 (Production method of specific aluminum silicate)
The method for producing a specific aluminum silicate according to the present invention comprises (a) a step of mixing a solution containing silicate ions and a solution containing aluminum ions to obtain a reaction product, and (b) the reaction product, A step of desalting and separating the solid, (c) a step of subjecting the solid separated in step (b) to a heat treatment in an aqueous medium in the presence of an acid, and (d) a heat treatment in step (c). And a step of desalting and solid separation of the product obtained as described above, and having other steps as necessary.
　反応生成物である特定アルミニウムケイ酸塩を含む溶液から共存イオンを脱塩処理した後に、酸の存在下で加熱処理することで、金属イオン吸着能及び金属イオン選択性に優れる特定アルミニウムケイ酸塩を効率よく製造することができる。 After desalting coexisting ions from a solution containing the specific aluminum silicate that is the reaction product, heat treatment in the presence of an acid allows the specific aluminum silicate to have excellent metal ion adsorption ability and metal ion selectivity. Can be manufactured efficiently.
　これは例えば以下のように考えることができる。規則的な構造の形成を阻害する共存イオンが除去された特定アルミニウムケイ酸塩を、酸の存在下で加熱処理することで、規則的な構造を有する特定アルミニウムケイ酸塩が形成される。特定アルミニウムケイ酸塩が規則的な構造を有することで、不要な金属イオンに対する親和性が向上し、効率よく金属イオンを吸着しつつ金属イオン選択性が高まると考えることができる。 This can be considered as follows, for example. The specific aluminum silicate from which the coexisting ions that inhibit the formation of the regular structure are removed is heat-treated in the presence of an acid, whereby the specific aluminum silicate having a regular structure is formed. It can be considered that the specific aluminum silicate has a regular structure, the affinity for unnecessary metal ions is improved, and the metal ion selectivity is enhanced while efficiently adsorbing the metal ions.
（ａ）反応生成物を得る工程
　反応生成物を得る工程では、ケイ酸イオンを含む溶液と、アルミニウムイオンを含む溶液とを混合して反応生成物である特定アルミニウムケイ酸塩及び共存イオンを含む混合溶液を得る。 (A) Step of obtaining reaction product In the step of obtaining reaction product, a solution containing silicate ions and a solution containing aluminum ions are mixed to contain a specific aluminum silicate and coexisting ions which are reaction products. A mixed solution is obtained.
　特定アルミニウムケイ酸塩を合成する際、原料には、ケイ酸イオン及びアルミニウムイオンが必要となる。ケイ酸イオンを含む溶液（以下、「ケイ酸溶液」ともいう）を構成するケイ酸源としては、溶媒和した際にケイ酸イオンが生じるものであれば特に制限されない。例えば、オルトケイ酸ナトリウム、メタケイ酸ナトリウム、テトラエトキシシラン等のテトラアルコキシシランなどが挙げられるが、これらに限定されるものではない。 When synthesizing a specific aluminum silicate, silicate ions and aluminum ions are required as raw materials. The silicic acid source constituting the solution containing silicate ions (hereinafter also referred to as “silicate solution”) is not particularly limited as long as silicate ions are generated when solvated. Examples thereof include, but are not limited to, tetraalkoxysilanes such as sodium orthosilicate, sodium metasilicate, and tetraethoxysilane.
　また、アルミニウムイオンを含む溶液（以下、「アルミニウム溶液」ともいう）を構成するアルミニウム源は、溶媒和した際にアルミニウムイオンが生じるものであれば特に制限されない。例えば、塩化アルミニウム、過塩素酸アルミニウム、硝酸アルミニウム、アルミニウムｓｅｃ－ブトキシド等が挙げられるが、これらに限定されるものではない。 Further, the aluminum source constituting the solution containing aluminum ions (hereinafter also referred to as “aluminum solution”) is not particularly limited as long as aluminum ions are generated when solvated. Examples thereof include, but are not limited to, aluminum chloride, aluminum perchlorate, aluminum nitrate, and aluminum sec-butoxide.
　溶媒としては、原料であるケイ酸源及びアルミニウム源と溶媒和し易いものを適宜選択して使用することができる。具体的には、水、エタノール等を使用することができる。加熱処理時における溶液中の共存イオンの低減、及び、取扱の容易さから、水を用いることが好ましい。 As the solvent, a material that can easily be solvated with the silicate source and the aluminum source as raw materials can be appropriately selected and used. Specifically, water, ethanol or the like can be used. It is preferable to use water from the viewpoint of reducing the coexisting ions in the solution during the heat treatment and ease of handling.
　これらの原料をそれぞれ溶媒に溶解させて原料溶液（ケイ酸溶液及びアルミニウム溶液）を調製した後、原料溶液を互いに混合して混合溶液を得る。混合溶液中のＳｉ及びＡｌの元素比Ｓｉ／Ａｌは、得られる特定アルミニウムケイ酸塩におけるＳｉ及びＡｌの元素比Ｓｉ／Ａｌに合わせて、モル比で０．３以上１．０未満となるように調整し、好ましくは０．４以上０．６以下となるように調整し、より好ましくは０．４５以上０．５５以下となるように調整する。元素比Ｓｉ／Ａｌを０．３以上１．０未満とすることで、所望の規則的な構造を有する特定アルミニウムケイ酸塩が合成され易くなる。 These raw materials are dissolved in a solvent to prepare raw material solutions (silicic acid solution and aluminum solution), and then the raw material solutions are mixed with each other to obtain a mixed solution. The element ratio Si / Al of the Si and Al in the mixed solution is 0.3 to less than 1.0 in molar ratio in accordance with the element ratio Si / Al of Si and Al in the specific aluminum silicate obtained. It adjusts so that it may become 0.4 or more and 0.6 or less, More preferably, it adjusts so that it may become 0.45 or more and 0.55 or less. When the element ratio Si / Al is 0.3 or more and less than 1.0, a specific aluminum silicate having a desired regular structure is easily synthesized.
　また、原料溶液の混合の際には、アルミニウム溶液に対してケイ酸溶液を徐々に加えることが好ましい。このようにすることで、所望の特定アルミニウムケイ酸塩の形成阻害要因となりうる、ケイ酸の重合を抑えることができる。 In addition, when mixing the raw material solution, it is preferable to gradually add the silicic acid solution to the aluminum solution. By doing in this way, the polymerization of silicic acid which can become a formation inhibition factor of desired specific aluminum silicate can be suppressed.
　ケイ酸溶液のケイ素原子濃度は、特に制限されるものではない。好ましくは１ｍｍｏｌ／Ｌ～１０００ｍｍｏｌ／Ｌである。 The silicon atom concentration of the silicate solution is not particularly limited. Preferably, it is 1 mmol / L to 1000 mmol / L.
　ケイ酸溶液のケイ素原子濃度が１ｍｍｏｌ／Ｌ以上であると、生産性が向上し、効率よく特定アルミニウムケイ酸塩を製造することができる。またケイ酸溶液のケイ素原子濃度が１０００ｍｍｏｌ／Ｌ以下であると、ケイ素原子濃度に応じて生産性がより向上する。 When the silicon atom concentration of the silicate solution is 1 mmol / L or more, productivity is improved and specific aluminum silicate can be produced efficiently. Moreover, productivity improves more according to a silicon atom concentration as the silicon atom concentration of a silicic acid solution is 1000 mmol / L or less.
　アルミニウム溶液のアルミニウム原子濃度は、特に制限されるものではない。好ましくは１００ｍｍｏｌ／Ｌ～１０００ｍｍｏｌ／Ｌである。 The aluminum atom concentration of the aluminum solution is not particularly limited. Preferably, it is 100 mmol / L to 1000 mmol / L.
　アルミニウム溶液のアルミニウム原子濃度が１００ｍｍｏｌ／Ｌ以上であると、生産性が向上し、効率よく特定アルミニウムケイ酸塩を製造することができる。またアルミニウム原子濃度が１０００ｍｍｏｌ／Ｌ以下であると、アルミニウム原子濃度に応じて生産性がより向上する。 When the aluminum atom concentration of the aluminum solution is 100 mmol / L or more, productivity is improved and specific aluminum silicate can be efficiently produced. Further, when the aluminum atom concentration is 1000 mmol / L or less, the productivity is further improved according to the aluminum atom concentration.
（ｂ）第一洗浄工程（脱塩及び固体分離）
　ケイ酸イオンを含む溶液とアルミニウムイオンを含む溶液とを混合し、反応生成物として共存イオンを含む特定アルミニウムケイ酸塩を生成させた後、生成した共存イオンを含む特定アルミニウムケイ酸塩を脱塩及び固体分離する第一洗浄工程を行う。第一洗浄工程では、混合溶液中から共存イオンの少なくとも一部を除去して混合溶液中の共存イオン濃度を低下させる。第一洗浄工程を行うことで、合成工程において所望の特定アルミニウムケイ酸塩を形成し易くなる。 (B) First washing step (desalting and solid separation)
A solution containing silicate ions and a solution containing aluminum ions are mixed to produce a specific aluminum silicate containing coexisting ions as a reaction product, and then the specific aluminum silicate containing the coexisting ions is desalted. And a first washing step for solid separation. In the first washing step, at least a part of the coexisting ions is removed from the mixed solution to reduce the coexisting ion concentration in the mixed solution. By performing the first cleaning step, it is easy to form a desired specific aluminum silicate in the synthesis step.
　第一洗浄工程で、脱塩及び固体分離する方法は、ケイ酸源及びアルミニウム源に由来するケイ酸イオン以外のアニオン（例えば塩化物イオン、硝酸イオン）及びアルミニウムイオン以外のカチオン（例えばナトリウムイオン）の少なくとも一部を除去（脱塩）して固体分離できればよく、特に制限されるものではない。第一洗浄工程としては例えば、遠心分離を用いる方法、透析膜を用いる方法、イオン交換樹脂を用いる方法等が挙げられる。 In the first washing step, desalting and solid separation include anions other than silicate ions derived from a silicate source and an aluminum source (for example, chloride ions and nitrate ions) and cations other than aluminum ions (for example, sodium ions). There is no particular limitation as long as at least a part of the solution can be removed (desalted) and separated into solids. Examples of the first washing step include a method using centrifugation, a method using a dialysis membrane, and a method using an ion exchange resin.
　第一洗浄工程は、共存イオンの濃度が所定の濃度以下になるように行うことが好ましい。具体的には例えば第一洗浄工程で得られる固体分離されたものを、濃度が６０ｇ／Ｌとなるように純水に分散させた場合に、その分散液の電気伝導率が４．０Ｓ／ｍ以下となるように行なうことが好ましく、１．０ｍＳ／ｍ以上３．０Ｓ／ｍ以下となるように行なうことがより好ましく、１．０ｍＳ／ｍ以上２．０Ｓ／ｍ以下となるように行なうことがより好ましい。 The first cleaning step is preferably performed so that the concentration of the coexisting ions is not more than a predetermined concentration. Specifically, for example, when the solid separated product obtained in the first washing step is dispersed in pure water so as to have a concentration of 60 g / L, the electrical conductivity of the dispersion is 4.0 S / m. It is preferable to carry out so that it is less than or equal to 1.0 mS / m or more and 3.0 S / m or less, more preferably 1.0 mS / m or more and 2.0 S / m or less. Is more preferable.
　分散液の電気伝導率が４．０Ｓ／ｍ以下であると、合成工程において所望の特定アルミニウムケイ酸塩がより形成しやすくなる傾向がある。 When the electrical conductivity of the dispersion is 4.0 S / m or less, the desired specific aluminum silicate tends to be more easily formed in the synthesis step.
　尚、電気伝導率は、ＨＯＲＩＢＡ社製：Ｆ－５５及び同社の一般的な電気伝導率セル：９３８２－１０Ｄを用いて、常温（２５℃）で測定される。 The electrical conductivity is measured at normal temperature (25 ° C.) using FORI 55 manufactured by HORIBA Co., Ltd. and a general electrical conductivity cell of 9382-10D.
　第一洗浄工程は、前記特定アルミニウムケイ酸塩を水性媒体に分散して分散物を得る工程と、前記分散物のｐＨを５～７に調整する工程と、特定アルミニウムケイ酸塩を析出させる工程とを含むことが好ましい。 The first washing step includes a step of dispersing the specific aluminum silicate in an aqueous medium to obtain a dispersion, a step of adjusting the pH of the dispersion to 5 to 7, and a step of precipitating the specific aluminum silicate Are preferably included.
　例えば第一洗浄工程を、遠心分離を用いて行なう場合、以下のようにして行うことができる。混合溶液にアルカリ等を加えてｐＨを５～８に調整する。ｐＨを調整した溶液を遠心分離した後、上澄み溶液を排出してゲル状沈殿物として固体分離する。固体分離されたものを溶媒に再分散させる。その際、遠心分離前の容積に戻すことが好ましい。再分散させた分散液を同様にして遠心分離して脱塩及び固体分離する操作を繰り返すことで、共存イオンの濃度を所定の濃度以下にすることができる。 For example, when the first washing step is performed using centrifugation, it can be performed as follows. The pH is adjusted to 5 to 8 by adding alkali or the like to the mixed solution. After centrifuging the pH-adjusted solution, the supernatant solution is discharged and the solid is separated as a gel-like precipitate. The separated solid is redispersed in a solvent. In that case, it is preferable to return to the volume before centrifugation. The concentration of the coexisting ions can be reduced to a predetermined concentration or less by repeating the operations of desalting and solid separation by centrifugal separation of the redispersed dispersion in the same manner.
　第一洗浄工程においてはｐＨを例えば５～８に調整するが、５．５～６．８であることが好ましく、５．８～６．５であることがより好ましい。ｐＨ調整に用いるアルカリは特に制限されない。例えば水酸化ナトリウム、アンモニア等が好ましい。 In the first washing step, the pH is adjusted to, for example, 5 to 8, but preferably 5.5 to 6.8, and more preferably 5.8 to 6.5. The alkali used for pH adjustment is not particularly limited. For example, sodium hydroxide and ammonia are preferable.
　また遠心分離の条件は製造規模や使用する容器等に応じて適宜選択される。例えば、室温下、１２００Ｇ以上で１～３０分間とすることができる。具体的には例えば、遠心分離装置としてＴＯＭＹ社製：Ｓｕｐｒｅｍａ２３、及び同社のスタンダードロータＮＡ－１６を用いる場合、室温下、３０００ｒｐｍ（１４５０Ｇ）以上で５～１０分間とすることができる。 Also, the centrifugation conditions are appropriately selected according to the production scale and the container used. For example, it can be 1 to 30 minutes at 1200 G or more at room temperature. Specifically, for example, in the case of using SUPREMA23 manufactured by TOMY as a centrifugal separator and its standard rotor NA-16, it can be set at 3000 rpm (1450 G) or more for 5 to 10 minutes at room temperature.
　第一洗浄工程における溶媒としては、原料と溶媒和し易いものを適宜選択して使用することができ、具体的には、水、エタノール等を使用することができるが、加熱合成時における溶液中の共存イオンの低減、及び、取扱の容易さから、水を用いることが好ましく、純水を用いることより好ましい。尚、繰り返し複数回の洗浄を行う際は、ｐＨ調整を省略することが好ましい。 As the solvent in the first washing step, a solvent that can easily be solvated with the raw material can be appropriately selected and used. Specifically, water, ethanol, or the like can be used. From the viewpoint of the reduction of coexisting ions and ease of handling, water is preferably used, and pure water is more preferably used. It should be noted that pH adjustment is preferably omitted when repeated washing is performed a plurality of times.
　第一洗浄工程における脱塩及び固体分離の処理回数は、共存イオンの残存量に応じて適宜設定すればよい。例えば１～６回とすることができる。３回程度の洗浄を繰り返すと、共存イオンの残存量が所望の特定アルミニウムケイ酸塩の合成に影響しない程少なくなる。 The number of treatments for desalting and solid separation in the first washing step may be appropriately set according to the remaining amount of coexisting ions. For example, it can be 1 to 6 times. If the washing is repeated about three times, the residual amount of coexisting ions is so small that it does not affect the synthesis of the desired specific aluminum silicate.
　ｐＨ調整する際のｐＨ測定は、一般的なガラス電極を用いたｐＨメータによって測定できる。具体的には、例えば、株式会社堀場製作所製の商品名：ＭＯＤＥＬ（Ｆ－５１）を使用することができる。 PH measurement at the time of pH adjustment can be performed with a pH meter using a general glass electrode. Specifically, for example, trade name: MODEL (F-51) manufactured by HORIBA, Ltd. can be used.
（ｃ）合成工程
　合成工程では、第一洗浄工程で固体分離されたものを水性媒体中、酸の存在下で加熱処理を行う。 (C) Synthesis step In the synthesis step, the solid separated in the first washing step is heat-treated in an aqueous medium in the presence of an acid.
　第一洗浄工程において共存イオンを低減させた特定アルミニウムケイ酸塩を含む溶液（分散液）を、酸の存在下に加熱処理することで、規則的な構造を有する特定アルミニウムケイ酸塩を形成することができる。 A specific aluminum silicate having a regular structure is formed by heat-treating a solution (dispersion) containing the specific aluminum silicate with reduced coexisting ions in the first washing step in the presence of an acid. be able to.
　合成工程は、第一洗浄工程で固体分離されたものを適宜希釈して希薄溶液として行なってもよく、また第一洗浄工程で固体分離されたものを高濃度溶液として行なってもよい。 The synthesis step may be performed as a dilute solution by appropriately diluting the solid separated in the first washing step, or may be carried out as a high-concentration solution after solid separation in the first washing step.
　合成工程を希薄溶液中で行なうことで、図４に示すような、規則的な構造が管状に伸展した構造を有する特定アルミニウムケイ酸塩（以下、「第一の特定アルミニウムケイ酸塩」ともいう）を得ることができる。また合成工程を高濃度溶液中で行なうことで、図３に示すような、規則的な構造に加えて粘度構造及び非晶質構造を有する特定アルミニウムケイ酸塩（以下、「第二の特定アルミニウムケイ酸塩」ともいう）を得ることができる。なお、第二の特定アルミニウムケイ酸塩は、長さ５０ｎｍ以上の管状物に成長するのに代えて、粘度構造及び非晶質構造の形成が増大しているものと推測される。 By performing the synthesis step in a dilute solution, a specific aluminum silicate having a structure in which a regular structure is extended into a tubular shape as shown in FIG. 4 (hereinafter also referred to as “first specific aluminum silicate”). ) Can be obtained. Further, by carrying out the synthesis step in a high concentration solution, a specific aluminum silicate having a viscosity structure and an amorphous structure in addition to a regular structure as shown in FIG. Silicate "). In addition, it replaces with the 2nd specific aluminum silicate growing in the tubular thing 50 nm or more in length, and it is estimated that the formation of a viscosity structure and an amorphous structure is increasing.
　第一及び第二のいずれの特定アルミニウムケイ酸塩も特定の規則的な構造を有することにより、優れた金属イオン吸着能及び金属イオン選択性を示す。 Both the first and second specific aluminum silicates have a specific regular structure, thereby exhibiting excellent metal ion adsorption ability and metal ion selectivity.
　合成工程において第一の特定アルミニウムケイ酸塩を得る場合の希釈条件としては、例えばケイ素原子濃度が２０ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度が６０ｍｍｏｌ／Ｌ以下とすることができる。中でも金属イオン吸着能及び金属イオン選択性の観点から、ケイ素原子濃度が０．１ｍｍｏｌ／Ｌ以上１０ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度が０．１ｍｍｏｌ／Ｌ以上３４ｍｍｏｌ／Ｌ以下であることが好ましく、ケイ素原子濃度が０．１ｍｍｏｌ／Ｌ以上２ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度が０．１ｍｍｏｌ／Ｌ以上７ｍｍｏｌ／Ｌ以下であることがより好ましい。 As dilution conditions for obtaining the first specific aluminum silicate in the synthesis step, for example, the silicon atom concentration can be 20 mmol / L or less and the aluminum atom concentration can be 60 mmol / L or less. Among these, from the viewpoint of metal ion adsorption ability and metal ion selectivity, it is preferable that the silicon atom concentration is 0.1 mmol / L or more and 10 mmol / L or less and the aluminum atom concentration is 0.1 mmol / L or more and 34 mmol / L or less. More preferably, the atomic concentration is from 0.1 mmol / L to 2 mmol / L and the aluminum atomic concentration is from 0.1 mmol / L to 7 mmol / L.
　ケイ素原子濃度を２０ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度を６０ｍｍｏｌ／Ｌ以下とすることで、第一の特定アルミニウムケイ酸塩を効率よく製造することができる。 By setting the silicon atom concentration to 20 mmol / L or less and the aluminum atom concentration to 60 mmol / L or less, the first specific aluminum silicate can be efficiently produced.
　また合成工程において第二の特定アルミニウムケイ酸塩を得る場合の高濃度条件としては、例えば、ケイ素原子濃度が１００ｍｍｏｌ／Ｌ以上且つアルミニウム原子濃度が１００ｍｍｏｌ／Ｌ以上とすることができる。中でも金属イオン吸着能及び金属イオン選択性の観点から、ケイ素原子濃度が１２０ｍｍｏｌ／Ｌ以上２０００ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度が１２０ｍｍｏｌ／Ｌ以上２０００ｍｍｏｌ／Ｌ以下であることが好ましく、ケイ素原子濃度が１５０ｍｍｏｌ／Ｌ以上１５００ｍｍｏｌ／Ｌ以下且つアルミニウム原子濃度が１５０ｍｍｏｌ／Ｌ以上１５００ｍｍｏｌ／Ｌ以下であることがより好ましい。 In addition, as a high concentration condition when obtaining the second specific aluminum silicate in the synthesis step, for example, the silicon atom concentration can be 100 mmol / L or more and the aluminum atom concentration can be 100 mmol / L or more. Among these, from the viewpoint of metal ion adsorption ability and metal ion selectivity, the silicon atom concentration is preferably 120 mmol / L or more and 2000 mmol / L or less, and the aluminum atom concentration is preferably 120 mmol / L or more and 2000 mmol / L or less, and the silicon atom concentration is 150 mmol. More preferably, the aluminum atom concentration is 150 mmol / L or more and 1500 mmol / L or less.
　ケイ素原子濃度を１００ｍｍｏｌ／Ｌ以上且つアルミニウム原子濃度を１００ｍｍｏｌ／Ｌ以上とすることで、第二の特定アルミニウムケイ酸塩を効率よく製造することができ、さらに特定アルミニウムケイ酸塩の生産性も向上する。 By setting the silicon atom concentration to 100 mmol / L or more and the aluminum atom concentration to 100 mmol / L or more, the second specific aluminum silicate can be efficiently produced, and the productivity of the specific aluminum silicate is also improved. To do.
　尚、上記ケイ素原子濃度及びアルミニウム原子濃度は、後述する酸性化合物を加えてｐＨを所定の範囲に調整した後のケイ素原子濃度及びアルミニウム素子濃度である。 The silicon atom concentration and the aluminum atom concentration are the silicon atom concentration and the aluminum element concentration after adjusting the pH to a predetermined range by adding an acidic compound described later.
　また、ケイ素原子濃度及びアルミニウム原子濃度は、ＩＣＰ発光分光装置（例えば、日立製作所社製ＩＣＰ発光分光装置：Ｐ－４０１０）を用いて測定される。 Also, the silicon atom concentration and the aluminum atom concentration are measured using an ICP emission spectrometer (for example, ICP emission spectrometer manufactured by Hitachi, Ltd .: P-4010).
　ケイ素原子濃度及びアルミニウム原子濃度が所定の濃度となるように調整する際には、溶媒を加えてもよい。溶媒としては、原料と溶媒和し易いものを適宜選択して使用することができ、具体的には、水、エタノール等を使用することができるが、加熱処理時における溶液中の共存イオンの低減、及び取扱の容易さから、水を用いることが好ましい。 When adjusting the silicon atom concentration and the aluminum atom concentration to be predetermined concentrations, a solvent may be added. As the solvent, one that can easily be solvated with the raw material can be appropriately selected and used. Specifically, water, ethanol, etc. can be used, but the coexisting ions in the solution during the heat treatment can be reduced. From the viewpoint of ease of handling, it is preferable to use water.
　合成工程においては、加熱処理の前に酸性化合物の少なくとも１種を加える。酸性化合物を加えた後のｐＨは特に制限されない。所望の特定アルミニウムケイ酸塩を効率よく得る観点から、ｐＨ３以上７未満であることが好ましく、ｐＨ３以上５以下であることがより好ましい。 In the synthesis step, at least one acidic compound is added before the heat treatment. The pH after adding the acidic compound is not particularly limited. From the viewpoint of efficiently obtaining the desired specific aluminum silicate, the pH is preferably from 3 to less than 7, and more preferably from 3 to 5.
　合成工程において加える酸性化合物は特に制限されるものではなく、有機酸であっても無機酸であってもよい。中でも無機酸を用いることが好ましい。無機酸として具体的には、塩酸、過塩素酸、硝酸等を挙げることができる。後に続く加熱処理時における溶液中の共存イオン種の低減を考慮すれば、使用したアルミニウム源に含まれるアニオンと同様のアニオンを生成する酸性化合物を用いることが好ましい。 The acidic compound added in the synthesis step is not particularly limited, and may be an organic acid or an inorganic acid. Among these, it is preferable to use an inorganic acid. Specific examples of the inorganic acid include hydrochloric acid, perchloric acid, nitric acid and the like. Considering the reduction of coexisting ion species in the solution during the subsequent heat treatment, it is preferable to use an acidic compound that generates an anion similar to the anion contained in the used aluminum source.
　酸性化合物を加えた後、加熱処理を行うことで、所望の構造を有する特定アルミニウムケイ酸塩を得ることができる。 A specific aluminum silicate having a desired structure can be obtained by performing a heat treatment after adding an acidic compound.
　加熱温度は特に制限されない。所望の特定アルミニウムケイ酸塩を効率よく得る観点から、８０℃～１６０℃であることが好ましい。 The heating temperature is not particularly limited. From the viewpoint of efficiently obtaining the desired specific aluminum silicate, the temperature is preferably from 80 ° C to 160 ° C.
　加熱温度が１６０℃以下であると、ベーマイト（水酸化アルミニウム）が析出することを抑制することができる傾向がある。また加熱温度が８０℃以上であると、所望の特定アルミニウムケイ酸塩の合成速度が向上し、より効率よく所望の特定アルミニウムケイ酸塩を製造できる傾向がある。 When the heating temperature is 160 ° C. or lower, precipitation of boehmite (aluminum hydroxide) tends to be suppressed. When the heating temperature is 80 ° C. or higher, the synthesis rate of the desired specific aluminum silicate is improved, and the desired specific aluminum silicate tends to be produced more efficiently.
　加熱時間は特に制限されるものではない。所望の構造を有する特定アルミニウムケイ酸塩をより効率的に得る観点から、９６時間（４日）以内であることが好ましい。 The heating time is not particularly limited. From the viewpoint of more efficiently obtaining a specific aluminum silicate having a desired structure, it is preferably within 96 hours (4 days).
　加熱時間が９６時間以下であると、より効率的に所望の特定アルミニウムケイ酸塩を製造することができる。 When the heating time is 96 hours or less, the desired specific aluminum silicate can be more efficiently produced.
（ｄ）第二洗浄工程（脱塩及び固体分離）
　合成工程において加熱処理して得られたものは、第二洗浄工程において脱塩及び固体分離される。これにより優れた金属イオン吸着能及び金属イオン選択性を有する特定アルミニウムケイ酸塩を得ることができる。これは例えば以下のように考えることができる。すなわち合成工程において加熱処理して得られたものは、特定アルミニウムケイ酸塩の吸着サイトが共存イオンで塞がれている場合があり、期待する程の金属イオン吸着能は得られない場合がある。そのため、合成工程で得られた特定アルミニウムケイ酸塩から共存イオンの少なくとも一部を除去する第二洗浄工程によって、脱塩及び固体分離することで優れた金属イオン吸着能及び金属イオン選択性を有する特定アルミニウムケイ酸塩を得ることができると考えることができる。 (D) Second washing step (desalting and solid separation)
What was obtained by heat treatment in the synthesis step is desalted and separated into solids in the second washing step. Thereby, the specific aluminum silicate which has the outstanding metal ion adsorption ability and metal ion selectivity can be obtained. This can be considered as follows, for example. That is, what is obtained by heat treatment in the synthesis step may be that the adsorption site of the specific aluminum silicate is clogged with coexisting ions, and the metal ion adsorption ability as expected may not be obtained. . Therefore, it has excellent metal ion adsorption ability and metal ion selectivity by desalting and solid separation by the second washing step that removes at least part of the coexisting ions from the specific aluminum silicate obtained in the synthesis step. It can be considered that a specific aluminum silicate can be obtained.
　第二洗浄工程は、ケイ酸イオン以外のアニオン及びアルミニウムイオン以外のカチオンの少なくとも一部を除去できればよく、合成工程前の第一洗浄工程と同様の操作であっても、異なる操作であってもよい。 The second washing step only needs to be able to remove at least a part of anions other than silicate ions and cations other than aluminum ions, and may be the same operation as the first washing step before the synthesis step or a different operation. Good.
　第二洗浄工程は、共存イオンの濃度が所定の濃度以下になるように行うことが好ましい。具体的には例えば第二洗浄工程で得られる固体分離されたものを、濃度が６０ｇ／Ｌとなるように純水に分散させた場合に、その分散液の電気伝導率が４．０Ｓ／ｍ以下となるように行なうことが好ましく、１．０ｍＳ／ｍ以上３．０Ｓ／ｍ以下となるように行なうことがより好ましく、１．０ｍＳ／ｍ以上２．０Ｓ／ｍ以下となるように行なうことがより好ましい。 The second washing step is preferably performed so that the concentration of coexisting ions is not more than a predetermined concentration. Specifically, for example, when the solid separated product obtained in the second washing step is dispersed in pure water so as to have a concentration of 60 g / L, the electrical conductivity of the dispersion is 4.0 S / m. It is preferable to carry out so that it is less than or equal to 1.0 mS / m or more and 3.0 S / m or less, more preferably 1.0 mS / m or more and 2.0 S / m or less. Is more preferable.
　分散液の電気伝導率が４．０Ｓ／ｍ以下であると、優れた金属イオン吸着能及び金属イオン選択性を有する特定アルミニウムケイ酸塩を得られやすくなる傾向がある。 When the electrical conductivity of the dispersion is 4.0 S / m or less, a specific aluminum silicate having excellent metal ion adsorption ability and metal ion selectivity tends to be easily obtained.
　第二洗浄工程を、遠心分離を用いて行なう場合、例えば以下のようにして行うことができる。混合溶液にアルカリ等を加えてｐＨを５～１０に調整する。ｐＨを調整した溶液を遠心分離した後、上澄み溶液を排出してゲル状沈殿物として固体分離する。次いで固体分離されたものを溶媒に再分散させる。その際、遠心分離前の容積に戻すことが好ましい。再分散させた分散液を同様にして遠心分離して脱塩及び固体分離する操作を繰り返すことで、共存イオンの濃度を所定の濃度以下にすることができる。 When the second washing step is performed using centrifugation, for example, it can be performed as follows. The pH is adjusted to 5 to 10 by adding alkali or the like to the mixed solution. After centrifuging the pH-adjusted solution, the supernatant solution is discharged and the solid is separated as a gel-like precipitate. The solid separated is then redispersed in a solvent. In that case, it is preferable to return to the volume before centrifugation. The concentration of the coexisting ions can be reduced to a predetermined concentration or less by repeating the operations of desalting and solid separation by centrifugal separation of the redispersed dispersion in the same manner.
　第二洗浄工程においてはｐＨを例えば５～１０に調整するが、８～１０であることが好ましい。ｐＨ調整に用いるアルカリは特に制限されない。例えば水酸化ナトリウム、アンモニア等が好ましい。 In the second washing step, the pH is adjusted to, for example, 5 to 10, preferably 8 to 10. The alkali used for pH adjustment is not particularly limited. For example, sodium hydroxide and ammonia are preferable.
　また遠心分離の条件は製造規模や使用する容器等に応じて適宜選択される。例えば、室温下、１２００Ｇ以上で１～３０分間とすることができる。具体的には例えば、遠心分離装置としてＴＯＭＹ社製：Ｓｕｐｒｅｍａ２３、及び同社のスタンダードロータＮＡ－１６を用いる場合、室温下、３０００ｒｐｍ（１４５０Ｇ）以上で５～１０分間とすることができる。 Also, the centrifugation conditions are appropriately selected according to the production scale and the container used. For example, it can be 1 to 30 minutes at 1200 G or more at room temperature. Specifically, for example, in the case of using SUPREMA23 manufactured by TOMY as a centrifugal separator and its standard rotor NA-16, it can be set at 3000 rpm (1450 G) or more for 5 to 10 minutes at room temperature.
　第二洗浄工程における溶媒としては、原料と溶媒和し易いものを適宜選択して使用することができ、具体的には、水、エタノール等を使用することができるが、共存イオンの低減、及び、取扱の容易さから、水を用いることが好ましく、純水を用いることより好ましい。尚、繰り返し複数回の洗浄を行う際は、ｐＨ調整を省略することが好ましい。 As a solvent in the second washing step, a solvent that can easily be solvated with the raw material can be appropriately selected and used. Specifically, water, ethanol, or the like can be used. From the viewpoint of ease of handling, it is preferable to use water, and it is more preferable to use pure water. It should be noted that pH adjustment is preferably omitted when repeated washing is performed a plurality of times.
　第二洗浄工程における脱塩及び固体分離の処理回数は、共存イオンの残存量によって設定すればよいが、１～６回が好ましく、３回程度の洗浄を繰り返すと、特定アルミニウムケイ酸塩における共存イオンの残存量が充分に低減される。 The number of treatments for desalting and solid separation in the second washing step may be set according to the residual amount of coexisting ions, but is preferably 1 to 6 times, and if the washing is repeated about 3 times, the coexistence in the specific aluminum silicate The remaining amount of ions is sufficiently reduced.
　第二洗浄工程後の分散液については、残存する共存イオンの中でも、特に金属イオンの吸着能に影響を与える塩化物イオン及びナトリウムイオンの濃度が低減されていることが好ましい。すなわち、第二洗浄工程における洗浄後のアルミニウムケイ酸塩は、当該アルミニウムケイ酸塩を水に分散させて濃度４００ｍｇ／Ｌの水分散液を調製したとき、当該水分散液において塩化物イオン濃度１００ｍｇ／Ｌ以下及びナトリウムイオン濃度１００ｍｇ／Ｌ以下を与えることが好ましい。塩化物イオン濃度１００ｍｇ／Ｌ以下且つナトリウムイオン濃度１００ｍｇ／Ｌ以下であると、吸着能を更に向上させることができる。塩化物イオン濃度は、５０ｍｇ／Ｌ以下がより好ましく、１０ｍｇ／Ｌ以下が更に好ましい。ナトリウムイオン濃度は、５０ｍｇ／Ｌ以下がより好ましく、１０ｍｇ／Ｌ以下が更に好ましい。塩化物イオン濃度及びナトリウムイオン濃度は、洗浄工程の処理回数やｐＨ調整に使用するアルカリの種類により調整することができる。 In the dispersion after the second washing step, it is preferable that among the remaining coexisting ions, the concentration of chloride ions and sodium ions that particularly affect the adsorption ability of metal ions is reduced. That is, when the aluminum silicate after washing in the second washing step is prepared by dispersing the aluminum silicate in water to prepare an aqueous dispersion having a concentration of 400 mg / L, the chloride ion concentration in the aqueous dispersion is 100 mg. / L or less and a sodium ion concentration of 100 mg / L or less are preferable. When the chloride ion concentration is 100 mg / L or less and the sodium ion concentration is 100 mg / L or less, the adsorption ability can be further improved. The chloride ion concentration is more preferably 50 mg / L or less, and still more preferably 10 mg / L or less. The sodium ion concentration is more preferably 50 mg / L or less, and still more preferably 10 mg / L or less. Chloride ion concentration and sodium ion concentration can be adjusted according to the number of treatments in the washing step and the type of alkali used for pH adjustment.
　尚、塩化物イオン濃度及びナトリウムイオン濃度は、イオンクロマトグラフィー（例えば、ダイオネクス社製ＤＸ－３２０及びＤＸ－１００）により通常の条件で測定される。 The chloride ion concentration and sodium ion concentration are measured under normal conditions by ion chromatography (for example, DX-320 and DX-100 manufactured by Dionex).
　また、特定アルミニウムケイ酸塩の分散物の濃度は、固体分離されたものを１１０度、２４時間乾燥して得られる固体の質量を基準とする。 Further, the concentration of the dispersion of the specific aluminum silicate is based on the mass of the solid obtained by drying the separated solid at 110 degrees for 24 hours.
　尚、ここで述べる「第二洗浄工程後の分散液」とは、第二洗浄工程を終了した後に、第二洗浄工程を行う前の容積に、溶媒を用いて容積を戻した分散液を意味する。用いる溶媒は、原料と溶媒和し易いものを適宜選択して使用することができ、具体的には、水、エタノール等を使用することができるが、特定アルミニウムケイ酸塩における共存イオンの残存量の低減、及び、取扱の容易さから、水を用いることが好ましい。 The “dispersion after the second washing step” described here means a dispersion in which the volume is returned to the volume before the second washing step after the second washing step by using a solvent. To do. As the solvent to be used, a solvent that easily solvates with the raw material can be appropriately selected and used. Specifically, water, ethanol or the like can be used, but the residual amount of coexisting ions in the specific aluminum silicate It is preferable to use water from the viewpoint of reduction of the amount and ease of handling.
　本発明に係る特定アルミニウムケイ酸塩のＢＥＴ比表面積は、第二洗浄工程の処理方法（例えば、合成溶液にアルカリを加えてｐＨを５～１０に調整し、遠心分離した後、上澄み溶液を排出してゲル状沈殿物として残った特定アルミニウムケイ酸塩を溶媒に再分散させ、遠心分離前の容積に戻す処理を一度もしくは複数回繰り返す方法）により調整することができる。 The BET specific surface area of the specific aluminum silicate according to the present invention is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution) Then, the specific aluminum silicate remaining as a gel-like precipitate is redispersed in a solvent, and the process of returning to the volume before centrifugation is repeated once or a plurality of times.
　また特定アルミニウムケイ酸塩の全細孔容積は、第二洗浄工程の処理方法（例えば、合成溶液にアルカリを加えてｐＨを５～１０に調整し、遠心分離した後、上澄み溶液を排出してゲル状沈殿物として残った特定アルミニウムケイ酸塩を溶媒に再分散させ、遠心分離前の容積に戻す処理を一度もしくは複数回繰り返す方法）により調整することができる。 The total pore volume of the specific aluminum silicate is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution). The specific aluminum silicate remaining as a gel-like precipitate can be adjusted by a method of redispersing in a solvent and returning to the volume before centrifugation once or a plurality of times.
　また特定アルミニウムケイ酸塩の平均細孔直径は、第二洗浄工程の処理方法（例えば、合成溶液にアルカリを加えてｐＨを５～１０に調整し、遠心分離した後、上澄み溶液を排出してゲル状沈殿物として残った特定アルミニウムケイ酸塩を溶媒に再分散させ、遠心分離前の容積に戻す処理を一度もしくは複数回繰り返す方法）により調整することができる。 The average pore diameter of the specific aluminum silicate is determined by the processing method of the second washing step (for example, adding alkali to the synthesis solution to adjust the pH to 5-10, centrifuging, and discharging the supernatant solution). The specific aluminum silicate remaining as a gel-like precipitate can be adjusted by a method of redispersing in a solvent and returning to the volume before centrifugation once or a plurality of times.
（リチウムイオン二次電池用正極の構成）
　本発明のリチウムイオン二次電池用正極は、前記特定アルミニウムケイ酸塩が表面に付与されている。特定アルミニウムケイ酸塩が正極の表面に付与されることで、正極でイオン化した不純物イオンが捕捉されるため、負極で金属イオンが還元されて金属が析出するのを抑えることができる。これにより、電池の短絡が抑えられる。また、正極から金属イオンが溶出するのが抑えられるため、正極活物質間の導電性を保持でき、電池特性の低下が抑制される。 (Configuration of positive electrode for lithium ion secondary battery)
The positive electrode for a lithium ion secondary battery of the present invention is provided with the specific aluminum silicate on the surface thereof. Since the specific aluminum silicate is applied to the surface of the positive electrode, impurity ions ionized at the positive electrode are captured, so that it is possible to suppress the metal ions from being reduced and the metal from being precipitated at the negative electrode. Thereby, the short circuit of a battery is suppressed. Moreover, since it is suppressed that a metal ion elutes from a positive electrode, the electroconductivity between positive electrode active materials can be hold | maintained and the fall of a battery characteristic is suppressed.
　このように特定アルミニウムケイ酸塩による不要な金属イオンの捕捉が効果的に行われるという観点から、特定アルミニウムケイ酸塩は正極の表面に付与されていれば、その他の構成は特に制限されない。例えば、具体的なリチウムイオン二次電池用正極の態様としては、集電体の上に正極活物質を含有する層（以下「正極層」と称する場合がある）が設けられ、前記正極層の表面に、特定アルミニウムケイ酸塩を含有する層が設けられた正極を挙げることができる。なお、特定アルミニウムケイ酸塩を含有する層と称するが、正極層の表面に特定アルミニウムケイ酸塩が付与されていれば、層状となっていなくともよい。 From the viewpoint that unnecessary metal ions are effectively trapped by the specific aluminum silicate as described above, other configurations are not particularly limited as long as the specific aluminum silicate is applied to the surface of the positive electrode. For example, as a specific aspect of the positive electrode for a lithium ion secondary battery, a layer containing a positive electrode active material (hereinafter sometimes referred to as a “positive electrode layer”) is provided on a current collector. A positive electrode provided with a layer containing a specific aluminum silicate on the surface can be given. In addition, although called the layer containing specific aluminum silicate, if the specific aluminum silicate is provided to the surface of the positive electrode layer, it may not be layered.
１）集電体
　本発明のリチウムイオン二次電池用正極における集電体は、リチウムイオン二次電池用正極に用いられる通常の集電体を適用することができ、例えば、アルミニウム、チタン、ステンレス鋼等の金属や合金を、箔状、穴開け箔状、メッシュ状等にした帯状のものを用いることができる。 1) Current collector As the current collector in the positive electrode for a lithium ion secondary battery of the present invention, a normal current collector used for a positive electrode for a lithium ion secondary battery can be applied. For example, aluminum, titanium, stainless steel A band-like material made of a metal such as steel or an alloy such as a foil shape, a perforated foil shape, or a mesh shape can be used.
２）正極層
　正極層は、前記集電体の上に設けられ、正極活物質を含有する。 2) Positive electrode layer The positive electrode layer is provided on the current collector and contains a positive electrode active material.
　前記正極活物質としては、通常リチウムイオン二次電池用正極に用いられる正極活物質を適用することができ、例えば、リチウムイオンをドーピング又はインターカレーション可能な金属化合物、金属酸化物、金属硫化物、又は導電性高分子材料を挙げることができる。具体的には例えば、コバルト酸リチウム（ＬｉＣｏＯ２）、ニッケル酸リチウム（ＬｉＮｉＯ２）、マンガン酸リチウム（ＬｉＭｎＯ２）、及びこれらの複酸化物（ＬｉＣｏｘＮｉｙＭｎｚＯ２、ｘ＋ｙ＋ｚ＝１、０＜ｘ、０＜ｙ；ＬｉＮｉ２－ｘＭｎｘＯ４、０＜ｘ≦２）、リチウムマンガンスピネル（ＬｉＭｎ２Ｏ４）、リチウムバナジウム化合物、Ｖ２Ｏ５、Ｖ６Ｏ１３、ＶＯ２、ＭｎＯ２、ＴｉＯ２、ＭｏＶ２Ｏ８、ＴｉＳ２、Ｖ２Ｓ５、ＶＳ２、ＭｏＳ２、ＭｏＳ３、Ｃｒ３Ｏ８、Ｃｒ２Ｏ５、オリビン型ＬｉＭＰＯ４（Ｍ：Ｃｏ、Ｎｉ、Ｍｎ、Ｆｅ）、ポリアセチレン、ポリアニリン、ポリピロール、ポリチオフェン、ポリアセン等の導電性ポリマー、多孔質炭素などを単独或いは混合して使用することができる。 As the positive electrode active material, a positive electrode active material usually used for a positive electrode for a lithium ion secondary battery can be applied. For example, metal compounds, metal oxides, metal sulfides that can be doped or intercalated with lithium ions Or a conductive polymer material. Specifically, for example, lithium cobaltate (LiCoO 2 ), lithium nickelate (LiNiO 2 ), lithium manganate (LiMnO 2 ), and double oxides thereof (LiCo x Ni y Mn z O 2 , x + y + z = 1, 0 <x, 0 <y; LiNi 2 -xMn x O 4 , 0 <x ≦ 2), lithium manganese spinel (LiMn 2 O 4 ), lithium vanadium compound, V 2 O 5 , V 6 O 13 , VO 2 , MnO 2 , TiO 2 , MoV 2 O 8 , TiS 2 , V 2 S 5 , VS 2 , MoS 2 , MoS 3 , Cr 3 O 8 , Cr 2 O 5 , olivine type LiMPO 4 (M: Co, Ni, Mn Fe), polyacetylene, polyaniline, polypyrrole, polythiophene, polyacene and other conductive polymers, porous carbon, etc. alone or Can be used as a mixture.
　正極層はバインダを含有してもよい。バインダとしては、例えば、スチレン－ブタジエン共重合体；エチレン性不飽和カルボン酸エステル（例えば、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ブチル（メタ）アクリレート、（メタ）アクリロニトリル、ヒドロキシエチル（メタ）アクリレート等）、及びエチレン性不飽和カルボン酸（例えば、アクリル酸、メタクリル酸、イタコン酸、フマル酸、マレイン酸等）を共重合して得られる（メタ）アクリル共重合体；ポリ弗化ビニリデン、ポリエチレンオキサイド、ポリエピクロルヒドリン、ポリホスファゼン、ポリアクリロニトリル、ポリイミド、ポリアミドイミドなどの高分子化合物が挙げられる。 The positive electrode layer may contain a binder. Examples of the binder include styrene-butadiene copolymer; ethylenically unsaturated carboxylic acid ester (for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylonitrile, hydroxyethyl (meth ) Acrylate, etc.), and (meth) acrylic copolymers obtained by copolymerizing ethylenically unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, etc.); polyvinylidene fluoride , Polymer compounds such as polyethylene oxide, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, polyimide, and polyamideimide.
　集電体上に正極層を形成する方法としては、前記正極活物質と前記バインダと溶媒とを含む正極合剤スラリーを集電体上に塗布し乾燥する方法等が挙げられる。又は、ペースト状の正極合剤スラリーをシート状、ペレット状等の形状に成形し、これを集電体と一体化して得てもよい。正極合剤スラリーの粘度は、塗工方法に合わせて適宜調整することが好ましい。 Examples of a method for forming the positive electrode layer on the current collector include a method in which a positive electrode mixture slurry containing the positive electrode active material, the binder, and a solvent is applied on the current collector and dried. Alternatively, the paste-like positive electrode mixture slurry may be formed into a sheet shape, a pellet shape, or the like and integrated with the current collector. The viscosity of the positive electrode mixture slurry is preferably adjusted as appropriate in accordance with the coating method.
　前記溶媒としては、例えば、アルコール類、グリコール類、セロソルブ類、アミノアルコール類、アミン類、ケトン類、カルボン酸アミド類、リン酸アミド類、スルホキシド類、カルボン酸エステル類、リン酸エステル類、エーテル類、ニトリル類、水等が挙げられる。バインダの溶解性や、導電剤の分散安定性を得るためには、極性の高い溶剤を使用することが好ましい。 Examples of the solvent include alcohols, glycols, cellosolves, amino alcohols, amines, ketones, carboxylic acid amides, phosphoric acid amides, sulfoxides, carboxylic acid esters, phosphoric acid esters, and ethers. , Nitriles, water and the like. In order to obtain the solubility of the binder and the dispersion stability of the conductive agent, it is preferable to use a highly polar solvent.
　具体的な前記溶媒としては、例えば、Ｎ，Ｎ－ジメチルホルムアミド、Ｎ，Ｎ－ジエチルホルムアミド、Ｎ，Ｎ－ジメチルアセトアミド、Ｎ，Ｎ－ジエチルアセトアミド等の様な窒素をジアルキル化したアミド系溶剤、Ｎ－メチルピロリドン、ヘキサメチル燐酸トリアミド、ジメチルスルホキシドなどが挙げられるが、これらに限定されない。二種類以上を併用することもできる。 Specific examples of the solvent include amide solvents obtained by dialkylating nitrogen such as N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, Examples include, but are not limited to, N-methylpyrrolidone, hexamethylphosphoric triamide, dimethyl sulfoxide, and the like. Two or more types can be used in combination.
　また正極合剤スラリーには、粘度を調整するために増粘剤を添加してもよい。増粘剤としては、例えば、カルボキシメチルセルロース、メチルセルロース、ヒドロキシメチルセルロース、エチルセルロース、ポリビニルアルコール、ポリアクリル酸（塩）、酸化スターチ、リン酸化スターチ、カゼインなどを使用することができる。 Further, a thickener may be added to the positive electrode mixture slurry in order to adjust the viscosity. As the thickener, for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
　また、前記正極合剤スラリーには、必要に応じて導電剤を混合してもよい。前記導電剤としては、例えば、ケッチェンブラックやアセチレンブラック、チャンネルブラック、ファーネスブラック、ランプブラック、サーマルブラック等のカーボンブラック類；鱗片状黒鉛のような天然黒鉛や人造黒鉛、膨張黒鉛などのグラファイト類；炭素繊維や金属繊維などの導電性繊維類；銅や銀、ニッケル、アルミニウム等の金属粉末類；ポリフェニレン誘導体等の有機導電性材料；などが挙げられる。また、これらを単体で用いてもよいし、複数を混合して用いてもよい。導電剤の含有率は、正極活物質に対して０．１質量％～２０質量％程度とすればよい。 In addition, a conductive agent may be mixed in the positive electrode mixture slurry as necessary. Examples of the conductive agent include carbon blacks such as ketjen black, acetylene black, channel black, furnace black, lamp black, and thermal black; natural graphite such as flake graphite, graphite such as artificial graphite, and expanded graphite Conductive fibers such as carbon fibers and metal fibers; metal powders such as copper, silver, nickel, and aluminum; organic conductive materials such as polyphenylene derivatives; These may be used alone or in combination. The content of the conductive agent may be about 0.1% by mass to 20% by mass with respect to the positive electrode active material.
　前記正極合剤スラリーを集電体に塗布する方法については、特に制限はなく公知の方法を用いることができる。具体的には、ダイコーティング法、ディップコーティング法、ロールコーティング法、ドクターコーティング法、スプレーコーティング法、グラビアコーティング法、スクリーン印刷法、静電塗装法等が挙げられる。又、塗布後に平版プレスやカレンダーロール等による圧延処理を行ってもよい。 The method for applying the positive electrode mixture slurry to the current collector is not particularly limited, and a known method can be used. Specific examples include a die coating method, a dip coating method, a roll coating method, a doctor coating method, a spray coating method, a gravure coating method, a screen printing method, and an electrostatic coating method. Moreover, you may perform the rolling process by a lithographic press, a calender roll, etc. after application | coating.
　また、シート状、ペレット状等の形状に成形された正極合剤スラリーと集電体との一体化は、例えば、ロール、プレス、もしくはこれらの組み合わせ等、公知の方法により行うことができる。 Further, the integration of the positive electrode mixture slurry and the current collector formed into a sheet shape, a pellet shape, or the like can be performed by a known method such as a roll, a press, or a combination thereof.
　正極層の厚みとしては、一般的には１μｍ以上５００μｍ以下であり、好ましくは１０μｍ以上３００μｍ以下である。 The thickness of the positive electrode layer is generally 1 μm or more and 500 μm or less, preferably 10 μm or more and 300 μm or less.
３）特定アルミニウムケイ酸塩を含有する層
　前記特定アルミニウムケイ酸塩を含有する層は、前記正極層の上に設けられ、いずれの方法によって形成されていてもよい。そのなかでも、正極上に均一に特定アルミニウムケイ酸塩を分散させることができ、それにより不要な金属イオンを効果的に吸着することができる観点から、前記特定アルミニウムケイ酸塩を含む分散液によって形成されることが好ましい。 3) Layer containing specific aluminum silicate The layer containing the specific aluminum silicate is provided on the positive electrode layer, and may be formed by any method. Among them, the specific aluminum silicate can be uniformly dispersed on the positive electrode, and thereby, unnecessary metal ions can be effectively adsorbed. Preferably it is formed.
　前記分散液は、例えば、前記特定アルミニウムケイ酸塩をバインダや溶剤とともに撹拌機、ボールミル、スーパーサンドミル、加圧ニーダ等の分散装置により混練して調製することができる。この分散液を前記正極層の上に塗布して特定アルミニウムケイ酸塩を含有する層を形成することができる。 The dispersion can be prepared, for example, by kneading the specific aluminum silicate together with a binder and a solvent by a dispersing device such as a stirrer, a ball mill, a super sand mill, or a pressure kneader. This dispersion can be applied onto the positive electrode layer to form a layer containing a specific aluminum silicate.
　上記分散液を正極層上に塗布する方法としては、特に限定されない。例えば、メタルマスク印刷法、静電塗装法、ディップコート法、スプレーコート法、ロールコート法、ドクターブレード法、グラビアコート法、スクリーン印刷法など公知の方法が挙げられる。塗布後は、必要に応じて平板プレス、カレンダーロール等による圧延処理を行うことが好ましい。 The method for applying the dispersion on the positive electrode layer is not particularly limited. For example, known methods such as a metal mask printing method, an electrostatic coating method, a dip coating method, a spray coating method, a roll coating method, a doctor blade method, a gravure coating method, and a screen printing method can be used. After the application, it is preferable to perform a rolling process using a flat plate press, a calender roll or the like, if necessary.
　前記分散液の溶媒としては、水、１－メチル－２－ピロリドン、アルコール類（メタノール、エタノール、１－プロパノール、２－プロパノール、１－ブタノール、２－ブタノール、２－メチル－１－プロパノール、２－メチル－２－プロパノール等）などが挙げられ、環境負荷の低減の観点から水であることがより好ましい。 Examples of the solvent for the dispersion include water, 1-methyl-2-pyrrolidone, alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2 -Methyl-2-propanol, etc.), and water is more preferable from the viewpoint of reducing environmental burden.
　前記分散液中の前記特定アルミニウムケイ酸塩の含有率は、例えば、０．０１質量％～５０質量％であることが好ましく、０．１質量％～３０質量％であることがより好ましく、１質量％～２０質量％であることが更に好ましい。 The content of the specific aluminum silicate in the dispersion is, for example, preferably 0.01% by mass to 50% by mass, more preferably 0.1% by mass to 30% by mass. More preferably, the content is from 20% by mass to 20% by mass.
　リチウムイオン二次電池用正極における前記特定アルミニウムケイ酸塩の付与量は、０．０１ｇ／ｍ２～５０ｇ／ｍ２程度であることが好ましく、０．０５ｇ／ｍ２～３０ｇ／ｍ２であることがより好ましく、０．１ｇ／ｍ２～２０ｇ／ｍ２であることが更に好ましい。 Application amount of the specific aluminum silicate in the positive electrode for a lithium ion secondary battery, it is preferably, 0.05g / m 2 ~ 30g / m 2 is 0.01g / m 2 ~ 50g / m 2 about More preferably, it is more preferably 0.1 g / m 2 to 20 g / m 2 .
　前記分散液は、更にバインダを含有することが好ましい。特定アルミニウムケイ酸塩の分散液にバインダを添加することで特定アルミニウムケイ酸塩が正極に固定化される。このため、電池を作製する際に特定アルミニウムケイ酸塩が粉落ちすることない上、充放電時でも正極上に存在できるので効率よく不要な金属イオンを吸着することができる。 The dispersion preferably further contains a binder. The specific aluminum silicate is fixed to the positive electrode by adding a binder to the dispersion of the specific aluminum silicate. For this reason, when producing a battery, since specific aluminum silicate does not fall off and can exist on a positive electrode also at the time of charging / discharging, an unnecessary metal ion can be adsorb | sucked efficiently.
　前記分散液に含有させるバインダとしては、特に制限されないが、電池の構成材料という観点からバインダとして、正極材層に用いられるバインダであるとより好ましい。 The binder to be contained in the dispersion is not particularly limited, but is preferably a binder used for the positive electrode material layer as a binder from the viewpoint of a battery constituent material.
　前記特定アルミニウムケイ酸塩を含有する層中のバインダの含有比率は、特定アルミニウムケイ酸塩とバインダの合計１００質量部に対して０．１質量部～１５質量部であることが好ましく、０．３質量部～１０質量部であることがより好ましい。 The content ratio of the binder in the layer containing the specific aluminum silicate is preferably 0.1 parts by mass to 15 parts by mass with respect to 100 parts by mass in total of the specific aluminum silicate and the binder. More preferably, it is 3 to 10 parts by mass.
　バインダの含有比率が０．１質量部以上であることで特定アルミニウムケイ酸塩が効果的に正極に固定化され、特定アルミニウムケイ酸塩を付与した効果が持続的に得られる。一方、１５質量部以下であることで、質量当たりの金属吸着効率を上げることができる。 When the content ratio of the binder is 0.1 parts by mass or more, the specific aluminum silicate is effectively fixed to the positive electrode, and the effect of providing the specific aluminum silicate is continuously obtained. On the other hand, the metal adsorption | suction efficiency per mass can be raised because it is 15 mass parts or less.
　また分散液には、粘度を調整するために増粘剤を添加してもよい。増粘剤としては、例えば、カルボキシメチルセルロース、メチルセルロース、ヒドロキシメチルセルロース、エチルセルロース、ポリビニルアルコール、ポリアクリル酸（塩）、酸化スターチ、リン酸化スターチ、カゼインなどを使用することができる。 Further, a thickener may be added to the dispersion to adjust the viscosity. As the thickener, for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
４）その他の層
　本発明のリチウムイオン二次電池用正極では、その他の層を設けてもよい。例えば、集電体と正極層との間に、集電体と正極層との密着性の向上のための下地層を設けてもよい。前記下地層は、電解液の溶媒に溶解、膨潤しないポリマーを含むことが好ましく、また、電極の電気抵抗を低減して導電性を確保するために、導電性物質を含有してもよい。 4) Other layers In the positive electrode for lithium ion secondary batteries of the present invention, other layers may be provided. For example, an underlayer for improving the adhesion between the current collector and the positive electrode layer may be provided between the current collector and the positive electrode layer. The underlayer preferably contains a polymer that does not dissolve or swell in the solvent of the electrolytic solution, and may contain a conductive substance in order to reduce the electrical resistance of the electrode and ensure conductivity.
＜リチウムイオン二次電池＞
　本発明のリチウムイオン二次電池は、上述の正極と、負極と、電解液とを含んで構成される。本発明の正極は、前記特定アルミニウムケイ酸塩が表面に付与されている。 <Lithium ion secondary battery>
The lithium ion secondary battery of this invention is comprised including the above-mentioned positive electrode, a negative electrode, and electrolyte solution. In the positive electrode of the present invention, the specific aluminum silicate is provided on the surface.
１）負極
　負極の態様としては、例えば、集電体の上に、負極活物質を含有する層（以下「負極層」と称する場合がある）が設けられたものが挙げられる。 1) Negative electrode As an aspect of a negative electrode, the thing provided with the layer (henceforth a "negative electrode layer") containing a negative electrode active material on the electrical power collector is mentioned, for example.
　本発明のリチウムイオン二次電池用負極における集電体は、リチウムイオン二次電池用負極に用いられる通常の集電体を適用することができ、例えば、アルミニウム、銅、ニッケル、チタン、ステンレス鋼等を、箔状、穴開け箔状、メッシュ状等にした帯状のものを用いればよい。また、多孔性材料、例えばポーラスメタル（発泡メタル）やカーボンペーパーなども使用可能である。 As the current collector in the negative electrode for a lithium ion secondary battery of the present invention, a normal current collector used for a negative electrode for a lithium ion secondary battery can be applied. For example, aluminum, copper, nickel, titanium, stainless steel Or the like may be used in the form of a foil, a punched foil, a mesh or the like. A porous material such as porous metal (foamed metal) or carbon paper can also be used.
　負極層は、前記集電体の上に設けられ、負極活物質を含有する。 The negative electrode layer is provided on the current collector and contains a negative electrode active material.
　負極活物質としては、リチウムイオン二次電池用負極に用いられる通常のものを適用することができ、例えば、リチウムイオンをドーピング又はインターカレーション可能な炭素材料、金属化合物、金属酸化物、金属硫化物、導電性高分子材料などを挙げることができる。例えば、天然黒鉛、人造黒鉛、ケイ素、チタン酸リチウムなどを単独或いは併用して使用することができる。 As the negative electrode active material, normal materials used for negative electrodes for lithium ion secondary batteries can be applied. For example, carbon materials, metal compounds, metal oxides, metal sulfides capable of doping or intercalating lithium ions can be used. And conductive polymer materials. For example, natural graphite, artificial graphite, silicon, lithium titanate and the like can be used alone or in combination.
　前記負極はバインダを含有してもよい。前記バインダとしては、特に限定されず、例えば、スチレン－ブタジエン共重合体、（メタ）アクリル系共重合体［エチレン性不飽和カルボン酸エステル（例えば、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ブチル（メタ）アクリレート、ヒドロキシエチル（メタ）アクリレート等）、（メタ）アクリロニトリル、エチレン性不飽和カルボン酸（例えば、アクリル酸、メタクリル酸、イタコン酸、フマル酸、マレイン酸等）を共重合して得られる共重合体］、ポリ弗化ビニリデン、ポリエチレンオキサイド、ポリエピクロルヒドリン、ポリホスファゼン、ポリイミド、ポリアミドイミドなどの高分子化合物が挙げられる。 The negative electrode may contain a binder. The binder is not particularly limited. For example, styrene-butadiene copolymer, (meth) acrylic copolymer [ethylenically unsaturated carboxylic acid ester (for example, methyl (meth) acrylate, ethyl (meth) acrylate, Butyl (meth) acrylate, hydroxyethyl (meth) acrylate, etc.), (meth) acrylonitrile, ethylenically unsaturated carboxylic acid (for example, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, etc.) Copolymer obtained], polyvinylidene fluoride, polyethylene oxide, polyepichlorohydrin, polyphosphazene, polyimide, polyamideimide, and the like.
　集電体上に負極層を形成する方法としては、前記負極活物質及び前記バインダを溶媒とともに撹拌機、ボールミル、スーパーサンドミル、加圧ニーダ等の分散装置により混練して負極合剤スラリーを調製し、これを前記集電体上に塗布して乾燥する方法が挙げられる。又は、ペースト状の負極合剤スラリーをシート状、ペレット状等の形状に成形し、これを集電体と一体化して得てもよい。 As a method of forming a negative electrode layer on a current collector, a negative electrode mixture slurry is prepared by kneading the negative electrode active material and the binder together with a solvent by a dispersing device such as a stirrer, a ball mill, a super sand mill, and a pressure kneader. And a method of applying this onto the current collector and drying it. Alternatively, the paste-like negative electrode mixture slurry may be formed into a sheet shape, a pellet shape, or the like and integrated with the current collector.
　前記負極の負極層中のバインダの含有比率は、負極活物質とバインダの合計１００質量部に対して０．５質量部～２０質量部であることが好ましく、１質量部～１０質量部であることがより好ましい。 The binder content in the negative electrode layer of the negative electrode is preferably 0.5 parts by mass to 20 parts by mass with respect to 100 parts by mass in total of the negative electrode active material and the binder, and is 1 part by mass to 10 parts by mass. It is more preferable.
　前記バインダの含有比率が０．５質量％以上であることで密着性が良好で、充放電時の膨張・収縮によって負極が破壊されることが抑制される。一方、２０質量％以下であることで、電極抵抗が大きくなることを抑制できる。 When the content ratio of the binder is 0.5% by mass or more, the adhesion is good, and the negative electrode is prevented from being broken due to expansion / contraction during charge / discharge. On the other hand, it can suppress that electrode resistance becomes large because it is 20 mass% or less.
　また、上記負極合剤スラリーには、必要に応じて、導電剤を混合してもよい。導電剤としては、例えば、カーボンブラック、グラファイト、アセチレンブラック、あるいは導電性を示す酸化物や窒化物等が挙げられる。導電剤の使用量は、負極活物質に対して０．１質量％～２０質量％程度とすればよい。 In addition, a conductive agent may be mixed in the negative electrode mixture slurry as necessary. Examples of the conductive agent include carbon black, graphite, acetylene black, or conductive oxides and nitrides. The amount of the conductive agent used may be about 0.1% by mass to 20% by mass with respect to the negative electrode active material.
　また負極合剤スラリーには、粘度を調整するために増粘剤を添加してもよい。増粘剤としては、例えば、カルボキシメチルセルロース、メチルセルロース、ヒドロキシメチルセルロース、エチルセルロース、ポリビニルアルコール、ポリアクリル酸（塩）、酸化スターチ、リン酸化スターチ、カゼインなどを使用することができる。 Further, a thickener may be added to the negative electrode mixture slurry in order to adjust the viscosity. As the thickener, for example, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (salt), oxidized starch, phosphorylated starch, casein and the like can be used.
　上記負極合剤スラリーを集電体に塗布する方法としては、特に限定されない。例えば、メタルマスク印刷法、静電塗装法、ディップコート法、スプレーコート法、ロールコート法、ドクターブレード法、グラビアコート法、スクリーン印刷法など公知の方法が挙げられる。塗布後は、必要に応じて平板プレス、カレンダーロール等による圧延処理を行うことが好ましい。 The method for applying the negative electrode mixture slurry to the current collector is not particularly limited. For example, known methods such as a metal mask printing method, an electrostatic coating method, a dip coating method, a spray coating method, a roll coating method, a doctor blade method, a gravure coating method, and a screen printing method can be used. After the application, it is preferable to perform a rolling process using a flat plate press, a calender roll or the like, if necessary.
　また、シート状、ペレット状等の形状に成形された負極合剤スラリーと集電体との一体化は、例えば、ロール、プレス、これらの組み合わせ等、公知の方法により行うことができる。 Further, the integration of the negative electrode mixture slurry and the current collector formed into a sheet shape, a pellet shape or the like can be performed by a known method such as a roll, a press, or a combination thereof.
　負極層の厚みとしては、一般的には１μｍ以上５００μｍ以下であり、好ましくは１０μｍ以上３００μｍ以下である。 The thickness of the negative electrode layer is generally 1 μm or more and 500 μm or less, preferably 10 μm or more and 300 μm or less.
　前記集電体上に形成された負極層及び集電体と一体化した負極層は、用いたバインダに応じて熱処理することが好ましい。例えば、ポリアクリロニトリルを主骨格としたバインダを用いた場合は、１００～１８０℃で、ポリイミド、ポリアミドイミドを主骨格としたバインダを用いた場合には１５０～４５０℃で熱処理することが好ましい。 The negative electrode layer formed on the current collector and the negative electrode layer integrated with the current collector are preferably heat-treated according to the binder used. For example, when a binder having polyacrylonitrile as the main skeleton is used, heat treatment is preferably performed at 100 to 180 ° C., and when using a binder having polyimide or polyamideimide as the main skeleton, heat treatment is preferably performed at 150 to 450 ° C.
　この熱処理により溶媒の除去、バインダの硬化による高強度化が進み、粒子間及び粒子と集電体間の密着性が向上できる。尚、これらの熱処理は、処理中の集電体の酸化を防ぐため、ヘリウム、アルゴン、窒素等の不活性雰囲気、又は真空雰囲気で行うことが好ましい。 This heat treatment increases the strength by removing the solvent and curing the binder, and improves the adhesion between the particles and between the particles and the current collector. These heat treatments are preferably performed in an inert atmosphere such as helium, argon, nitrogen, or a vacuum atmosphere in order to prevent oxidation of the current collector during the treatment.
　また、熱処理後に、負極は加圧プレス（加圧処理）することが好ましい。加圧処理することで電極密度を調整することができる。例えば、天然黒鉛を負極材として用いたリチウムイオン二次電池用負極では、電極密度が１．０ｇ／ｃｍ３～２．０ｇ／ｃｍ３であることが好ましい。電極密度については、高いほど体積容量が向上する。 Moreover, it is preferable that the negative electrode is pressure-pressed (pressure treatment) after the heat treatment. The electrode density can be adjusted by applying pressure treatment. For example, in a negative electrode for a lithium ion secondary battery using natural graphite as a negative electrode material, the electrode density is preferably 1.0 g / cm 3 to 2.0 g / cm 3 . About electrode density, volume capacity improves, so that it is high.
２）電解液
　本発明のリチウムイオン二次電池に用いる電解液は特に制限されず、公知のものを用いることができる。例えば、電解質を有機溶媒に溶解させた電解液を用いることにより、非水系リチウムイオン二次電池となる。 2) Electrolyte The electrolyte used for the lithium ion secondary battery of the present invention is not particularly limited, and a known one can be used. For example, a non-aqueous lithium ion secondary battery is obtained by using an electrolytic solution in which an electrolyte is dissolved in an organic solvent.
　前記電解質としては、例えば、ＬｉＰＦ６、ＬｉＣｌＯ４、ＬｉＢＦ４、ＬｉＣｌＦ４、ＬｉＡｓＦ６、ＬｉＳｂＦ６、ＬｉＡｌＯ４、ＬｉＡｌＣｌ４、ＬｉＮ（ＣＦ３ＳＯ２）２、ＬｉＮ（Ｃ２Ｆ５ＳＯ２）２、ＬｉＣ（ＣＦ３ＳＯ２）３、ＬｉＣｌ、ＬｉＩなどの溶媒和しにくいアニオンを生成するリチウム塩を例示することができる。 As the electrolyte, for example, LiPF 6, LiClO 4, LiBF 4, LiClF 4, LiAsF 6, LiSbF 6, LiAlO 4, LiAlCl 4, LiN (CF 3 SO 2) 2, LiN (C 2 F 5 SO 2) 2 Examples thereof include lithium salts that generate anions that are difficult to solvate, such as LiC (CF 3 SO 2 ) 3 , LiCl, and LiI.
　また前記電解質の濃度は特に限定されない。例えば、電解液１Ｌに対して電解質０．３モル～５モルであることが好ましく、０．５モル～３モルであることがより好ましく、０．８モル～１．５モルであることが特に好ましい。 Further, the concentration of the electrolyte is not particularly limited. For example, the electrolyte is preferably 0.3 to 5 mol, more preferably 0.5 to 3 mol, and particularly preferably 0.8 to 1.5 mol with respect to 1 L of the electrolyte. preferable.
　前記有機溶剤としては、カーボネート類（プロピレンカーボネート、エチレンカーボネート、ジエチルカーボネート、ジメチルカーボネート、ブチレンカーボネート、ビニレンカーボネート、フルオロエチレンカーボネート、エチルメチルカーボネート、メチルプロピルカーボネート、ブチルメチルカーボネート、エチルプロピルカーボネート、ブチルエチルカーボネート、ジプロピルカーボネート等）、ケトン類（シクロペンタノン等）、ラクトン類（γ－ブチロラクトン等）、エステル類（酢酸メチル、酢酸エチル等）、鎖状エーテル類（１，２－ジメトキシエタン、ジメチルエーテル、ジエチルエーテル等）、環状エーテル類（テトラヒドロフラン、２－メチルテトラヒドロフラン、ジオキソラン、４－メチルジオキソラン等）、ケトン類（シクロペンタノン等）、スルホラン類（スルホラン、３－メチルスルホラン、２，４－ジメチルスルホラン等）、スルホキシド類（ジメチルスルホキシド等）、ニトリル類（アセトニトリル、プロピオニトリル、ベンゾニトリル等）、アミド類（Ｎ，Ｎ－ジメチルホルムアミド、Ｎ，Ｎ－ジメチルアセトアミド等）、ウレタン類（３－メチル－１，３－オキサゾリジン－２－オン等）、ポリオキシアルキレングリコール類（ジエチレングリコール等）などの非プロトン性溶媒を例示することができる。 Examples of the organic solvent include carbonates (propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, methyl propyl carbonate, butyl methyl carbonate, ethyl propyl carbonate, butyl ethyl carbonate. , Dipropyl carbonate, etc.), ketones (cyclopentanone, etc.), lactones (γ-butyrolactone, etc.), esters (methyl acetate, ethyl acetate, etc.), chain ethers (1,2-dimethoxyethane, dimethyl ether, Diethyl ether, etc.), cyclic ethers (tetrahydrofuran, 2-methyltetrahydrofuran, dioxolane, 4-methyldioxolane, etc.), (Cyclopentanone, etc.), sulfolanes (sulfolane, 3-methylsulfolane, 2,4-dimethylsulfolane, etc.), sulfoxides (dimethylsulfoxide, etc.), nitriles (acetonitrile, propionitrile, benzonitrile, etc.), Non-amides (N, N-dimethylformamide, N, N-dimethylacetamide, etc.), urethanes (3-methyl-1,3-oxazolidine-2-one, etc.), polyoxyalkylene glycols (diethylene glycol, etc.), etc. A protic solvent can be illustrated.
　有機溶剤は、単独で用いてもよく２種以上の混合溶剤として用いてもよい。 The organic solvent may be used alone or as a mixed solvent of two or more.
３）セパレータ
　本発明のリチウムイオン二次電池は、セパレータを有してもよい。前記セパレータとしては、例えば、ポリエチレン、ポリプロピレン等のポリオレフィンを主成分とした不織布、クロス、微孔フィルム又はそれらを組み合わせたものを使用することができる。なお、作製するリチウムイオン二次電池の正極と負極が直接接触しない構造の場合は、セパレータを使用する必要はない。 3) Separator The lithium ion secondary battery of the present invention may have a separator. As the separator, for example, a nonwoven fabric mainly composed of polyolefin such as polyethylene and polypropylene, cloth, microporous film, or a combination thereof can be used. In the case where the positive electrode and the negative electrode of the lithium ion secondary battery to be manufactured are not in direct contact, it is not necessary to use a separator.
４）構成
　本発明のリチウムイオン二次電池の構造は、特に限定されないが、通常、正極及び負極と、必要に応じて設けられるセパレータとを、扁平渦巻状に巻回して巻回式極板群としたり、これらを平板状として積層して積層式極板群としたりし、これら極板群を外装体中に封入した構造とするのが一般的である。 4) Structure The structure of the lithium ion secondary battery of the present invention is not particularly limited. Usually, a positive electrode and a negative electrode, and a separator provided as necessary are wound in a flat spiral shape to form a wound electrode group. In general, these are laminated as a flat plate to form a laminated electrode plate group, and the electrode plate group is generally enclosed in an exterior body.
　本発明のリチウムイオン二次電池は、特に限定されないが、ペーパー型電池、ボタン型電池、コイン型電池、積層型電池、円筒型電池、角型電池などとして使用される。 The lithium ion secondary battery of the present invention is not particularly limited, but is used as a paper-type battery, a button-type battery, a coin-type battery, a laminated battery, a cylindrical battery, a square battery, or the like.
　次に、本発明を実施例及び比較例に基づいて具体的に説明するが、本発明は、以下の実施例に限定されるものではない。 Next, the present invention will be specifically described based on examples and comparative examples, but the present invention is not limited to the following examples.
　なお、下記実施例１～４、比較例１～３では、予備試験として、特定アルミニウムケイ酸塩の水中での金属イオン吸着能の評価を行い、実施例５および６では、モデル電解液中での金属イオン吸着能の評価を行った。 In Examples 1 to 4 and Comparative Examples 1 to 3 below, metal ion adsorption ability of specific aluminum silicate in water was evaluated as a preliminary test. In Examples 5 and 6, the model electrolyte was used as a model electrolyte. The metal ion adsorption ability was evaluated.
　実施例７では、リチウムイオン二次電池を作製し、初期容量、充放電特性およびインピーダンスの測定を行った。 In Example 7, a lithium ion secondary battery was produced, and the initial capacity, charge / discharge characteristics, and impedance were measured.
［実施例１］
＜アルミニウムケイ酸塩の作製＞
　濃度：７００ｍｍｏｌ／Ｌの塩化アルミニウム水溶液（５００ｍＬ）に、濃度：３５０ｍｍｏｌ／Ｌのオルトケイ酸ナトリウム水溶液（５００ｍＬ）を加え、３０分間攪拌した。この溶液に、濃度：１ｍｏｌ／Ｌの水酸化ナトリウム水溶液を３３０ｍＬ加え、ｐＨ＝６．１に調整した。 [Example 1]
<Preparation of aluminum silicate>
A concentration: 350 mmol / L sodium orthosilicate aqueous solution (500 mL) was added to a 700 mmol / L aluminum chloride aqueous solution (500 mL), and the mixture was stirred for 30 minutes. To this solution, 330 mL of an aqueous sodium hydroxide solution having a concentration of 1 mol / L was added to adjust the pH to 6.1.
　ｐＨ調整した溶液を３０分間攪拌後、遠心分離装置としてＴＯＭＹ社製：Ｓｕｐｒｅｍａ２３及びスタンダードロータＮＡ－１６を用い、回転速度：３，０００回転／分で、５分間の遠心分離を行った。遠心分離後、上澄み溶液を排出し、ゲル状沈殿物を純水に再分散させ、遠心分離前の容積に戻した。このような遠心分離による脱塩処理を３回行った。 After the pH-adjusted solution was stirred for 30 minutes, centrifugal separation was performed for 5 minutes at a rotation speed of 3,000 rpm using a TOMY Corporation: Suprema 23 and standard rotor NA-16 as a centrifugal separator. After centrifugation, the supernatant solution was discharged, the gel precipitate was redispersed in pure water, and returned to the volume before centrifugation. Such desalting treatment by centrifugation was performed three times.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物を、濃度が６０ｇ／Ｌとなるように純水に分散し、ＨＯＲＩＢＡ社製：Ｆ－５５及び電気伝導率セル：９３８２－１０Ｄを用いて、常温（２５℃）で、電気伝導率を測定したところ、１．３Ｓ／ｍであった。 The gel-like precipitate obtained after the third desalting of the desalting treatment was dispersed in pure water so as to have a concentration of 60 g / L, using HORIBA: F-55 and conductivity cell: 9382-10D. The electrical conductivity measured at room temperature (25 ° C.) was 1.3 S / m.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物に、濃度：１ｍｏｌ／Ｌの塩酸を１３５ｍＬ加えてｐＨ＝３．５に調整し、３０分間攪拌した。このときの溶液中のケイ素原子濃度及びアルミニウム原子濃度を、ＩＣＰ発光分光装置：Ｐ－４０１０（日立製作所社製）を用いて、常法により測定したところ、ケイ素原子の濃度は２１３ｍｍｏｌ／Ｌ、アルミニウム原子の濃度は４２６ｍｍｏｌ／Ｌであった。 135 mg of hydrochloric acid having a concentration of 1 mol / L was added to the gel-like precipitate obtained after the third supernatant discharge of the desalting treatment to adjust to pH = 3.5, followed by stirring for 30 minutes. When the silicon atom concentration and the aluminum atom concentration in the solution at this time were measured by an ordinary method using an ICP emission spectrometer: P-4010 (manufactured by Hitachi, Ltd.), the silicon atom concentration was 213 mmol / L, aluminum The concentration of atoms was 426 mmol / L.
　次に、この溶液を乾燥器に入れ、９８℃で４８時間（２日間）加熱した。 Next, this solution was put in a drier and heated at 98 ° C. for 48 hours (2 days).
　加熱後溶液（アルミニウムケイ酸塩濃度４７ｇ／Ｌ）に、濃度：１ｍｏｌ／Ｌの水酸化ナトリウム水溶液を１８８ｍＬ添加し、ｐＨ＝９．１に調整した。ｐＨ調整により溶液中のアルミニウムケイ酸塩を凝集させ、上記同様の遠心分離でこの凝集体を沈殿させることで、上澄み液を排出した。これに純水を添加して遠心分離前の容積に戻すという脱塩処理を３回行った。 188 mL of a 1 mol / L sodium hydroxide aqueous solution was added to the solution after heating (aluminum silicate concentration 47 g / L) to adjust the pH to 9.1. The aluminum silicate in the solution was agglomerated by adjusting the pH, and the agglomerate was precipitated by centrifugation similar to the above, thereby discharging the supernatant. The desalting process of adding pure water to this and returning to the volume before centrifugation was performed 3 times.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物を、濃度が６０ｇ／Ｌとなるように純水に分散し、ＨＯＲＩＢＡ社製：Ｆ－５５及び電気伝導率セル：９３８２－１０Ｄを用いて、常温（２５℃）で電気伝導率を測定したところ、０．６Ｓ／ｍであった。 The gel-like precipitate obtained after the third desalting of the desalting treatment was dispersed in pure water so as to have a concentration of 60 g / L, using HORIBA: F-55 and conductivity cell: 9382-10D. The electrical conductivity measured at room temperature (25 ° C.) was 0.6 S / m.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物を、６０℃で１６時間乾燥して３０ｇの粉末を得た。この粉末を試料Ａとした。 The gel precipitate obtained after the third desalting of the desalting treatment was dried at 60 ° C. for 16 hours to obtain 30 g of powder. This powder was designated as sample A.
＜元素比Ｓｉ／Ａｌ＞
　試料Ａについて、常法のＩＣＰ発光分光分析（ＩＣＰ発光分光装置：Ｐ－４０１０（日立製作所社製））から求めたＳｉ及びＡｌの元素比Ｓｉ／Ａｌは、０．５であった。 <Element ratio Si / Al>
For sample A, the elemental ratio Si / Al of Si / Al determined by a conventional ICP emission spectroscopic analysis (ICP emission spectrophotometer: P-4010 (manufactured by Hitachi, Ltd.)) was 0.5.
＜ＢＥＴ比表面積、全細孔容積、平均細孔直径＞
　試料ＡのＢＥＴ比表面積、全細孔容積、及び平均細孔直径を、窒素吸着能から測定した。評価装置には、ＱＵＡＮＴＡＣＨＲＯＭＥ社製：ＡＵＴＯＳＯＲＢ－１（商品名）を用いた。これらの測定を行う際には、後述する試料の前処理を行った後、評価温度を７７Ｋとし、評価圧力範囲を相対圧（飽和蒸気圧に対する平衡圧力）にて１未満としている。 <BET specific surface area, total pore volume, average pore diameter>
The BET specific surface area, total pore volume, and average pore diameter of Sample A were measured from the nitrogen adsorption capacity. As the evaluation device, AUTASORB-1 (trade name) manufactured by QUANTACHROME was used. When performing these measurements, after pre-treatment of the sample described later, the evaluation temperature is 77K, and the evaluation pressure range is less than 1 in relative pressure (equilibrium pressure with respect to the saturated vapor pressure).
　前処理として、０．０５ｇの試料Ａを投入した測定用セルに、真空ポンプで脱気及び加熱を自動制御で行った。この処理の詳細条件は、１０Ｐａ以下に減圧した後、１１０℃で加熱し、３時間以上保持した後、減圧した状態を保ったまま常温（２５℃）まで自然冷却するという設定とした。 As pretreatment, the measurement cell charged with 0.05 g of sample A was automatically degassed and heated with a vacuum pump. The detailed conditions of this treatment were set such that the pressure was reduced to 10 Pa or less, heated at 110 ° C., held for 3 hours or more, and then naturally cooled to room temperature (25 ° C.) while maintaining the reduced pressure.
　評価の結果、試料ＡのＢＥＴ比表面積は３６３ｍ２／ｇ、全細孔容積は０．２２ｃｍ３／ｇ、そして平均細孔直径は２．４ｎｍであった。 As a result of the evaluation, the BET specific surface area of Sample A was 363 m 2 / g, the total pore volume was 0.22 cm 3 / g, and the average pore diameter was 2.4 nm.
＜２７Ａｌ－ＮＭＲ＞
　２７Ａｌ－ＮＭＲスペクトルの測定装置として、ブルカー・バイオスピン製ＡＶ４００ＷＢ型を用い、下記条件で測定を行った。 <27Al-NMR>
The measurement was performed under the following conditions using a Bruker BioSpin AV400WB model as a 27Al-NMR spectrum measuring apparatus.
　共鳴周波数：１０４ＭＨｚ
　測定方法：ＭＡＳ（シングルパルス）
　ＭＡＳ回転数：１０ｋＨｚ
　測定領域：５２ｋＨｚ
　データポイント数：４０９６
　ｒｅｓｏｌｕｔｉｏｎ（測定領域／データポイント数）：１２．７Ｈｚ
　パルス幅：３．０μｓｅｃ
　遅延時間：２秒
　化学シフト値基準：α－アルミナを３．９４ｐｐｍ
　ｗｉｎｄｏｗ関数：指数関数
　Ｌｉｎｅ　Ｂｒｏａｄｅｎｉｎｇ係数：１０Ｈｚ
　図１に試料Ａの２７Ａｌ－ＮＭＲのスペクトルを示す。図１に示されるように、３ｐｐｍ近辺にピークを有した。また５５ｐｐｍ近辺に若干のピークが見られた。３ｐｐｍ近辺のピークに対する、５５ｐｐｍ付近のピークの面積比率は、１５％であった。 Resonance frequency: 104MHz
Measuring method: MAS (single pulse)
MAS rotation speed: 10 kHz
Measurement area: 52 kHz
Number of data points: 4096
resolution (measurement area / number of data points): 12.7 Hz
Pulse width: 3.0 μsec
Delay time: 2 seconds Chemical shift value standard: 3.94 ppm of α-alumina
window function: exponential function Line Broadening coefficient: 10 Hz
FIG. 1 shows the 27Al-NMR spectrum of Sample A. As shown in FIG. 1, it had a peak around 3 ppm. A slight peak was observed around 55 ppm. The area ratio of the peak near 55 ppm to the peak near 3 ppm was 15%.
＜２９Ｓｉ－ＮＭＲ＞
　２９Ｓｉ－ＮＭＲスペクトル測定装置としては、ブルカー・バイオスピン製ＡＶ４００ＷＢ型を用い、下記条件で測定を行った。 <29Si-NMR>
As a 29 Si-NMR spectrum measuring apparatus, an AV400WB type manufactured by Bruker BioSpin was used, and measurement was performed under the following conditions.
　共鳴周波数：７９．５ＭＨｚ
　測定方法：ＭＡＳ（シングルパルス）
　ＭＡＳ回転数：６ｋＨｚ
　測定領域：２４ｋＨｚ
　データポイント数：２０４８
　ｒｅｓｏｌｕｔｉｏｎ（測定領域／データポイント数）：５．８Ｈｚ
　パルス幅：４．７μｓｅｃ
　遅延時間：６００秒
　化学シフト値基準：ＴＭＳＰ－ｄ４（３－（トリメチルシリル）（２，２，３，３－２Ｈ４）プロピオン酸ナトリウム）を１．５２ｐｐｍ
　ｗｉｎｄｏｗ関数：指数関数
　Ｌｉｎｅ　Ｂｒｏａｄｅｎｉｎｇ係数：５０Ｈｚ
　図２に試料Ａの２９Ｓｉ－ＮＭＲのスペクトルを示す。図２に示されるように、－７８ｐｐｍ近辺及び－８５ｐｐｍ近辺にピークを有した。－７８ｐｐｍ及び－８５ｐｐｍ近辺のピークの面積を上記方法により測定した。その結果、－７８ｐｐｍのピークＡの面積を１．００としたとき、－８５ｐｐｍのピークＢの面積は２．６１であった。 Resonance frequency: 79.5 MHz
Measuring method: MAS (single pulse)
MAS rotation speed: 6 kHz
Measurement area: 24 kHz
Number of data points: 2048
resolution (measurement area / number of data points): 5.8 Hz
Pulse width: 4.7 μsec
Delay time: 600 seconds Chemical shift value criteria: TMSP-d4 (3- (trimethylsilyl) (2,2,3,3-2H4) sodium propionate) 1.52 ppm
window function: exponential function Line Broadening coefficient: 50 Hz
FIG. 2 shows the 29Si-NMR spectrum of Sample A. As shown in FIG. 2, there were peaks at around -78 ppm and around -85 ppm. The peak areas around −78 ppm and −85 ppm were measured by the above method. As a result, when the area of the peak A at −78 ppm was 1.00, the area of the peak B at −85 ppm was 2.61.
＜透過型電子顕微鏡（ＴＥＭ）写真観察＞
　図３に、試料Ａを１００，０００倍で観察したときの透過型電子顕微鏡（ＴＥＭ）写真を示す。尚、ＴＥＭ観察は、透過型電子顕微鏡（日立ハイテクノロジーズ社製、Ｈ－７１００ＦＡ型）を用いて、１００ｋＶの加速電圧で行なった。また、ＴＥＭ観察対象の試料Ａは以下のようにして調製した。すなわち、最終の脱塩処理工程前の、加熱後溶液（アルミニウムケイ酸塩濃度４７ｇ／Ｌ）を純水で１０倍に希釈し、超音波照射処理を５分間行ったものをＴＥＭ観察試料調整用の支持体上に滴下し、次いで自然乾燥して薄膜とすることで調製した。 <Transmission electron microscope (TEM) photo observation>
FIG. 3 shows a transmission electron microscope (TEM) photograph of sample A observed at a magnification of 100,000. The TEM observation was performed using a transmission electron microscope (H-7100FA, manufactured by Hitachi High-Technologies Corporation) at an acceleration voltage of 100 kV. A sample A to be observed with TEM was prepared as follows. That is, the solution after heating (aluminum silicate concentration of 47 g / L) before the final desalting treatment process was diluted 10 times with pure water and subjected to ultrasonic irradiation for 5 minutes. It was prepared by dropping it onto a support and then drying it naturally to form a thin film.
　図３に示されるように、長さ５０ｎｍ以上の管状物が存在していない。 As shown in FIG. 3, there is no tubular product having a length of 50 nm or more.
＜粉末Ｘ線回折＞
　粉末Ｘ線回折は、リガク社製：Ｇｅｉｇｅｒｆｌｅｘ ＲＡＤ－２Ｘ（商品名）を用い、Ｘ線源としてＣｕＫα線を用いて行なった。図６に、試料Ａの粉末Ｘ線回折のスペクトルを示す。２θ＝２６．９°近辺、そして４０．３°近辺にブロードなピークが観測された。また２θ＝１８．８°、２０．３°、２７．８°、４０．６°、そして５３．３°近辺にシャープなピークが観測された。２θ＝２０°及び３５°近辺にはピークが観測されなかった。 <Powder X-ray diffraction>
Powder X-ray diffraction was performed using Rigaku Corporation: Geigerflex RAD-2X (trade name) and CuKα rays as an X-ray source. FIG. 6 shows a powder X-ray diffraction spectrum of Sample A. Broad peaks were observed around 2θ = 26.9 ° and around 40.3 °. In addition, sharp peaks were observed in the vicinity of 2θ = 18.8 °, 20.3 °, 27.8 °, 40.6 °, and 53.3 °. No peaks were observed around 2θ = 20 ° and 35 °.
＜水中での金属イオン吸着能＞
　金属イオン吸着能評価はＩＣＰ発光分光分析（ＩＣＰ発光分光装置：Ｐ－４０１０（日立製作所社製））によって行った。 <Metal ion adsorption capacity in water>
The metal ion adsorption ability was evaluated by ICP emission spectroscopic analysis (ICP emission spectrophotometer: P-4010 (manufactured by Hitachi, Ltd.)).
　金属イオン吸着能の評価に当たり、まず、Ｌｉ＋、Ｎｉ２＋又はＭｎ２＋について、各々の金属硫酸塩及び純水を用いて１００ｐｐｍの金属イオン溶液を調製した。その調製溶液に対し試料Ａが１．０質量％となるように添加し、十分混合した後、静置した。そして、試料Ａ添加前後の各々の金属イオン濃度をＩＣＰ発光分光分析にて測定した。 In evaluating the metal ion adsorption capacity, first, a 100 ppm metal ion solution was prepared for each of Li + , Ni 2+, or Mn 2+ using each metal sulfate and pure water. It added so that the sample A might be 1.0 mass% with respect to the prepared solution, and it left still, after mixing sufficiently. Then, each metal ion concentration before and after the addition of sample A was measured by ICP emission spectroscopic analysis.
　試料Ａ添加後の濃度はＮｉ２＋が５ｐｐｍ未満、Ｍｎ２＋が１０ｐｐｍとなった。これに対して、Ｌｉ＋は９０ｐｐｍであり、殆ど吸着されていなかった。したがって、試料Ａはリチウムイオン二次電池に不要なＮｉ２＋及びＭｎ２＋を吸着させるが、充放電に必須なＬｉ＋は殆ど吸着しないため、電池の性能を阻害せずに短絡を抑えることができることが分かる。 Concentrations after addition of sample A were less than 5 ppm for Ni 2+ and 10 ppm for Mn 2+ . On the other hand, Li + was 90 ppm and was hardly adsorbed. Therefore, although sample A adsorbs Ni 2+ and Mn 2+ unnecessary for the lithium ion secondary battery, it hardly adsorbs Li + essential for charge and discharge, and can suppress a short circuit without impairing the performance of the battery. I understand.
［比較例１］
　市販品の活性炭（和光純薬工業社製、活性炭素、破砕状、２～５ｍｍ）を試料Ｂとした。水中での金属イオン吸着能について、試料Ｂ添加後の濃度はＮｉ２＋が５０ｐｐｍ、Ｍｎ２＋が６０ｐｐｍ、Ｌｉ＋が１００ｐｐｍとなった。 [Comparative Example 1]
Sample B was commercially available activated carbon (manufactured by Wako Pure Chemical Industries, Ltd., activated carbon, crushed, 2 to 5 mm). Regarding the metal ion adsorption capacity in water, the concentrations after addition of Sample B were 50 ppm for Ni 2+ , 60 ppm for Mn 2+ , and 100 ppm for Li + .
［比較例２］
　市販品のシリカゲル（和光純薬工業社製、小粒状（白色））を試料Ｃとした。水中での金属イオン吸着能について、試料Ｃ添加後の濃度はＮｉ２＋が１００ｐｐｍ、Ｍｎ２＋が１００ｐｐｍ、Ｌｉ＋が８０ｐｐｍとなった。 [Comparative Example 2]
Sample C was a commercially available silica gel (manufactured by Wako Pure Chemical Industries, Ltd., small granular (white)). Regarding the metal ion adsorption ability in water, the concentrations after addition of Sample C were 100 ppm for Ni 2+ , 100 ppm for Mn 2+ , and 80 ppm for Li + .
［比較例３］
　市販品のゼオライト４Ａ（和光純薬工業社製、モレキュラシーブス４Ａ、Ｓｉ／Ａｌのモル比＝１．０）を試料Ｄとした。水中での金属イオン吸着能について、試料Ｄ添加後の濃度はＮｉ２＋が３０ｐｐｍ、Ｍｎ２＋が１０ｐｐｍ、Ｌｉ＋が６０ｐｐｍとなった。 [Comparative Example 3]
Sample D was commercially available zeolite 4A (manufactured by Wako Pure Chemical Industries, Ltd., molecular sieves 4A, Si / Al molar ratio = 1.0). Concerning metal ion adsorption ability in water, the concentrations after addition of sample D were 30 ppm for Ni 2+ , 10 ppm for Mn 2+ , and 60 ppm for Li + .
　なお、ゼオライト４Ａを添加したＭｎ２＋溶液は静置すると茶色く濁った。
Figure JPOXMLDOC01-appb-T000001
 In addition, the Mn2 + solution to which zeolite 4A was added turned brown and cloudy when left standing.
Figure JPOXMLDOC01-appb-T000001
［実施例２］
＜アルミニウムケイ酸塩の作製＞
　濃度：１８０ｍｍｏｌ／Ｌの塩化アルミニウム水溶液（５００ｍＬ）に、濃度：７４ｍｍｏｌ／Ｌのオルトケイ酸ナトリウム水溶液（５００ｍＬ）を加え、３０分間攪拌した。この溶液に、濃度：１ｍｏｌ／Ｌの水酸化ナトリウム水溶液を９３ｍＬ加え、ｐＨ＝７．０に調整した。 [Example 2]
<Preparation of aluminum silicate>
A concentration: 74 mmol / L sodium orthosilicate aqueous solution (500 mL) was added to an aluminum chloride aqueous solution (500 mL) having a concentration of 180 mmol / L, followed by stirring for 30 minutes. To this solution, 93 mL of a 1 mol / L sodium hydroxide aqueous solution was added to adjust the pH to 7.0.
　ｐＨ調整した溶液を３０分間攪拌後、遠心分離装置としてＴＯＭＹ社製：Ｓｕｐｒｅｍａ２３及びスタンダードロータＮＡ－１６を用い、回転速度：３，０００回転／分で、５分間の遠心分離を行った。遠心分離後、上澄み溶液を排出し、ゲル状沈殿物を純水に再分散させ、遠心分離前の容積に戻した。このような遠心分離による脱塩処理を３回行った。 After the pH-adjusted solution was stirred for 30 minutes, centrifugal separation was performed for 5 minutes at a rotation speed of 3,000 rpm using a TOMY Corporation: Suprema 23 and standard rotor NA-16 as a centrifugal separator. After centrifugation, the supernatant solution was discharged, the gel precipitate was redispersed in pure water, and returned to the volume before centrifugation. Such desalting treatment by centrifugation was performed three times.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物を、濃度が６０ｇ／Ｌとなるように調整し、ＨＯＲＩＢＡ社製：Ｆ－５５及び電気伝導率セル：９３８２－１０Ｄを用いて、常温（２５℃）で、電気伝導率を測定したところ、１．３Ｓ／ｍであった。 The gel-like precipitate obtained after the third desalting of the desalting treatment was adjusted so as to have a concentration of 60 g / L, and it was used at normal temperature using FORI 55: F-55 and conductivity cell: 9382-10D. The electrical conductivity was measured at 25 ° C. and found to be 1.3 S / m.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物に純水を加え、容積を１２Ｌとした。その溶液に濃度：１ｍｏｌ／Ｌの塩酸を６０ｍＬ加えてｐＨ＝４．０に調整し、３０分間攪拌した。このときの溶液中のケイ素原子濃度及びアルミニウム原子濃度をＩＣＰ発光分光装置：Ｐ－４０１０（日立製作所社製）を用いて測定したところ、ケイ素原子濃度は２ｍｍｏｌ／Ｌであり、アルミニウム原子濃度は４ｍｍｏｌ／Ｌであった。 Pure water was added to the gel-like precipitate obtained after the supernatant was discharged for the third time in the desalting treatment to make the volume 12 L. The solution was adjusted to pH = 4.0 by adding 60 mL of hydrochloric acid having a concentration of 1 mol / L and stirred for 30 minutes. When the silicon atom concentration and the aluminum atom concentration in the solution at this time were measured using an ICP emission spectrometer: P-4010 (manufactured by Hitachi, Ltd.), the silicon atom concentration was 2 mmol / L and the aluminum atom concentration was 4 mmol. / L.
　次に、この溶液を乾燥器に入れ、９８℃で９６時間（４日間）加熱した。 Next, this solution was put in a dryer and heated at 98 ° C. for 96 hours (4 days).
　加熱後溶液（アルミニウムケイ酸塩濃度０．４ｇ／Ｌ）に、濃度：１ｍｏｌ／Ｌの水酸化ナトリウム水溶液を６０ｍＬ添加し、ｐＨ＝９．０に調整した。ｐＨ調整により溶液を凝集させ、遠心分離でこの凝集体を沈殿させ、第一洗浄工程と同様の遠心分離でこの凝集体を沈殿させることで、上澄み液を排出した。これに純水を添加して遠心分離前の容積に戻すという脱塩処理を３回行った。 After heating, 60 mL of a 1 mol / L sodium hydroxide aqueous solution was added to the solution (aluminum silicate concentration 0.4 g / L) to adjust the pH to 9.0. The solution was aggregated by adjusting the pH, the aggregate was precipitated by centrifugation, and the aggregate was precipitated by centrifugation similar to the first washing step, whereby the supernatant was discharged. The desalting process of adding pure water to this and returning to the volume before centrifugation was performed 3 times.
　脱塩処理３回目の上澄み排出後に得たゲル状沈殿物を、濃度が６０ｇ／Ｌとなるように調整し、ＨＯＲＩＢＡ社製：Ｆ－５５及び電気伝導率セル：９３８２－１０Ｄを用いて、常温（２５℃）で電気伝導率を測定したところ、０．６Ｓ／ｍであった。 The gel-like precipitate obtained after the third desalting of the desalting treatment was adjusted so as to have a concentration of 60 g / L, and it was used at normal temperature using FORI 55: F-55 and conductivity cell: 9382-10D. When the electric conductivity was measured at 25 ° C., it was 0.6 S / m.
　脱塩処理後に得たゲル状沈殿物を、６０℃で７２時間（３日間）乾燥して４．８ｇの粉末を得た。この粉末を試料Ｅとした。 The gel-like precipitate obtained after the desalting treatment was dried at 60 ° C. for 72 hours (3 days) to obtain 4.8 g of powder. This powder was designated as Sample E.
＜元素比Ｓｉ／Ａｌ＞
　常法のＩＣＰ発光分光分析（ＩＣＰ発光分光装置：Ｐ－４０１０（日立製作所社製））から求めたＳｉ及びＡｌの元素比Ｓｉ／Ａｌは、０．５であった。 <Element ratio Si / Al>
The element ratio Si / Al of Si and Al determined by a conventional ICP emission spectroscopic analysis (ICP emission spectrophotometer: P-4010 (manufactured by Hitachi, Ltd.)) was 0.5.
＜ＢＥＴ比表面積、全細孔容積、平均細孔直径＞
　実施例１と同様の方法で、ＢＥＴ比表面積、全細孔容積、及び平均細孔直径を、窒素吸着能から測定した。 <BET specific surface area, total pore volume, average pore diameter>
In the same manner as in Example 1, the BET specific surface area, the total pore volume, and the average pore diameter were measured from the nitrogen adsorption ability.
　評価の結果、試料ＥのＢＥＴ比表面積は３２３ｍ２／ｇ、全細孔容積は０．２２ｃｍ３／ｇ、そして平均細孔直径は２．７ｎｍとなった。 As a result of the evaluation, the BET specific surface area of Sample E was 323 m 2 / g, the total pore volume was 0.22 cm 3 / g, and the average pore diameter was 2.7 nm.
＜２７Ａｌ－ＮＭＲ＞
　図１に試料Ｅの２７Ａｌ－ＮＭＲのスペクトルを示す。図１に示すように、３ｐｐｍ近辺にピークを有した。また５５ｐｐｍ近辺に若干のピークが見られた。３ｐｐｍ近辺のピークに対する、５５ｐｐｍ近辺のピークの面積比率は、４％であった。 <27Al-NMR>
FIG. 1 shows the 27Al-NMR spectrum of Sample E. As shown in FIG. 1, it had a peak around 3 ppm. A slight peak was observed around 55 ppm. The area ratio of the peak around 55 ppm to the peak around 3 ppm was 4%.
＜２９Ｓｉ－ＮＭＲ＞
　図２に試料Ｅの２９Ｓｉ－ＮＭＲのスペクトルを示す。図２に示されるように、－７８ｐｐｍ及び－８５ｐｐｍ近辺にピークを有した。－７８ｐｐｍ及び－８５ｐｐｍ近辺のピークの面積を上記方法により測定した。その結果、－７８ｐｐｍ近辺のピークＡの面積を１．００としたとき、－８５ｐｐｍ近辺のピークＢの面積は０．４４であった。 <29Si-NMR>
FIG. 2 shows the 29Si-NMR spectrum of Sample E. As shown in FIG. 2, there were peaks near −78 ppm and −85 ppm. The peak areas around −78 ppm and −85 ppm were measured by the above method. As a result, when the area of peak A near −78 ppm was 1.00, the area of peak B near −85 ppm was 0.44.
＜透過型電子顕微鏡（ＴＥＭ）写真観察＞
　図４に、試料Ｅを実施例１と同様の方法により１００，０００倍で観察したときの透過型電子顕微鏡（ＴＥＭ）写真を示す。図４に示されるように管状物が生成しており、管状体１０ａの管部長さ方向の長さは、１ｎｍ～１０μｍ程度であり、外径は１．５～３．０ｎｍ程度であり、内径は０．７～１．４ｎｍ程度であった。 <Transmission electron microscope (TEM) photo observation>
In FIG. 4, the transmission electron microscope (TEM) photograph when the sample E is observed by 100,000 times by the same method as Example 1 is shown. As shown in FIG. 4, a tubular product is generated, the length of the tubular body 10a in the tube portion length direction is about 1 nm to 10 μm, the outer diameter is about 1.5 to 3.0 nm, and the inner diameter is Was about 0.7 to 1.4 nm.
＜粉末Ｘ線回折＞
　実施例１と同様の方法で、試料Ｅの粉末Ｘ線回折を行った。図６に、試料Ｅの粉末Ｘ線回折のスペクトルを示す。２θ＝４．８°、９．７°、１４．０°、１８．３°、２７．３°、そして４０．８°近辺にブロードなピークを有していた。２θ＝２０°及び３５°近辺にはピークが観測されなかった。 <Powder X-ray diffraction>
In the same manner as in Example 1, powder X-ray diffraction of Sample E was performed. FIG. 6 shows the powder X-ray diffraction spectrum of Sample E. It had broad peaks around 2θ = 4.8 °, 9.7 °, 14.0 °, 18.3 °, 27.3 °, and 40.8 °. No peaks were observed around 2θ = 20 ° and 35 °.
＜水中での金属イオン吸着能＞
　実施例１と同様の方法で、水中でのＭｎ２＋イオン吸着能を評価したところ、試料Ｅは試料Ａと同様の金属イオン吸着能を示した。 <Metal ion adsorption capacity in water>
When the Mn 2+ ion adsorption ability in water was evaluated in the same manner as in Example 1, Sample E showed the same metal ion adsorption ability as Sample A.
［実施例３］
　実施例１で作製した試料Ａを用い、試料Ａの添加量を下記表に示すように変更した以外は実施例１で説明した方法で、水中での金属イオン吸着能を評価した。その結果を下表に示す。
Figure JPOXMLDOC01-appb-T000002
 [Example 3]
The sample A prepared in Example 1 was used, and the ability to adsorb metal ions in water was evaluated by the method described in Example 1 except that the addition amount of Sample A was changed as shown in the following table. The results are shown in the table below.
Figure JPOXMLDOC01-appb-T000002
　上表に示されるように、試料Ａを０．５質量％添加すると、Ｍｎ２＋イオン濃度が半減した。そして、試料Ａを２．０質量％添加したときには、Ｍｎ２＋イオンが９５％捕捉された。 As shown in the above table, when 0.5% by mass of sample A was added, the Mn 2+ ion concentration was halved. When 2.0% by mass of sample A was added, 95% of Mn 2+ ions were trapped.
［実施例４］
　実施例１で作製した試料Ａを用い、金属イオン種をＣｕ２＋に、また金属イオン調整濃度を４００ｐｐｍに代えた以外は実施例１で説明した方法で、水中での金属イオン吸着能を評価した。このときのｐＨは５．１であった。試料Ａ添加後の濃度はＣｕ２＋が１６０ｐｐｍとなった。 [Example 4]
Using the sample A prepared in Example 1, the metal ion adsorption ability in water was evaluated by the method described in Example 1 except that the metal ion species was changed to Cu 2+ and the metal ion adjustment concentration was changed to 400 ppm. . The pH at this time was 5.1. The concentration after addition of Sample A was 160 ppm for Cu 2+ .
［実施例５］
＜モデル電解液中での金属イオン吸着能＞
　リチウムイオン二次電池への適用を想定し、モデル電解液中での金属イオン吸着能を評価した。溶媒としてジエチルカーボネート（ＤＥＣ）とエチレンカーボネート（ＥＣ）とを、体積比でＤＥＣ／ＥＣ＝１／１となるように混合した溶液を用い、溶質としてテトラフルオロほう酸ニッケルを初期Ｎｉ２＋イオン濃度が１００ｐｐｍとなるように加え、モデル電解液とした。 [Example 5]
<Metal ion adsorption capacity in model electrolyte>
Assuming application to lithium ion secondary batteries, the ability to adsorb metal ions in a model electrolyte was evaluated. Using a solution in which diethyl carbonate (DEC) and ethylene carbonate (EC) were mixed as a solvent so that the volume ratio was DEC / EC = 1/1, nickel tetrafluoroborate as an solute had an initial Ni 2+ ion concentration of 100 ppm. In addition, a model electrolyte was obtained.
　前記モデル電解液の３０ｍＬをガラス瓶に入れ、ここに試料Ａを０．３ｇ投入した。溶液を数分間攪拌した後、数時間静置した。試料添加前後の濃度変化をＩＣＰ発光分光分析（ＩＣＰ発光分光装置：ＳＰＳ５１００（エスアイアイ・ナノテクノロジー社製））にて測定した。なお、測定試料の前処理には酸分解（マイクロウェーブ法）を行った。 30 mL of the model electrolyte was put into a glass bottle, and 0.3 g of sample A was put therein. The solution was stirred for several minutes and then allowed to stand for several hours. The concentration change before and after the sample addition was measured by ICP emission spectroscopic analysis (ICP emission spectroscopic device: SPS5100 (manufactured by SII Nanotechnology)). In addition, acid decomposition (microwave method) was performed for the pretreatment of the measurement sample.
　上記において、試料Ａに代えて、前記試料Ｃ、前記試料Ｄ、前記試料Ｅ、及び市販品のゼオライト１３Ｘ（和光純薬工業社製、モレキュラシーブス１３Ｘ、Ｓｉ／Ａｌのモル比＝１．２）である試料Ｆを用いて、Ｎｉ２＋の吸着量を測定した。結果を下表に示す。
Figure JPOXMLDOC01-appb-T000003
 In the above, instead of the sample A, the sample C, the sample D, the sample E, and a commercially available zeolite 13X (manufactured by Wako Pure Chemical Industries, Ltd., molecular sieves 13X, Si / Al molar ratio = 1.2) Using the sample F, the adsorption amount of Ni 2+ was measured. The results are shown in the table below.
Figure JPOXMLDOC01-appb-T000003
　上表に示されるように、モデル電解液中で、実施例１及び２の特定アルミニウムケイ酸塩は、シリカゲル、ゼオライト４Ａ、ゼオライト１３Ｘよりも優れたＮｉ２＋イオン吸着能を示した。 As shown in the above table, in the model electrolyte, the specific aluminum silicates of Examples 1 and 2 exhibited Ni 2+ ion adsorption ability superior to silica gel, zeolite 4A, and zeolite 13X.
［実施例６］
　試料Ａの添加量を下表に示すように変更した以外は実施例５で説明した方法で、モデル電解液中でのＮｉ２＋イオン吸着能を評価した。その結果を下表に示す。
Figure JPOXMLDOC01-appb-T000004
 [Example 6]
The Ni 2+ ion adsorption ability in the model electrolyte was evaluated by the method described in Example 5 except that the amount of sample A added was changed as shown in the table below. The results are shown in the table below.
Figure JPOXMLDOC01-appb-T000004
　上表に示されるように、試料Ａを１．０質量％添加すると、Ｎｉ２＋イオンを８０％吸着した。そして、試料Ａを２．０質量％添加すると、Ｎｉ２＋イオンを９５％吸着した。 As shown in the table above, when Sample A was added by 1.0 mass%, Ni 2+ ions were adsorbed by 80%. When 2.0 mass% of sample A was added, 95% of Ni 2+ ions were adsorbed.
［実施例７］
＜正極の作製＞
　本実施例で使用した正極活物質は、平均粒径２０μｍ、最大粒径８０μｍのＬｉＭｎ２Ｏ４粉末である。この正極活物質と天然黒鉛、ポリフッ化ビニリデンの１－メチル－２－ピロリドン溶液を混合し、充分に混練したものを正極スラリーとした。ＬｉＭｎ２Ｏ４、天然黒鉛、ポリフッ化ビニリデンの混合比は、質量比で９０：６：４とした。このスラリーを、ドクターブレード法によって、乾燥後の塗布量が２５０ｇ／ｍ２となるように厚さ２０μｍのアルミニウム箔からなる正極集電体の表面に塗布した。この正極を１００℃で２時間乾燥した。 [Example 7]
<Preparation of positive electrode>
The positive electrode active material used in this example is LiMn 2 O 4 powder having an average particle size of 20 μm and a maximum particle size of 80 μm. This positive electrode active material, natural graphite, and a 1-methyl-2-pyrrolidone solution of polyvinylidene fluoride were mixed and sufficiently kneaded to obtain a positive electrode slurry. The mixing ratio of LiMn 2 O 4 , natural graphite, and polyvinylidene fluoride was 90: 6: 4 by mass ratio. This slurry was applied to the surface of a positive electrode current collector made of an aluminum foil having a thickness of 20 μm by a doctor blade method so that the coating amount after drying was 250 g / m 2 . This positive electrode was dried at 100 ° C. for 2 hours.
　実施例１で作製した特定アルミニウムケイ酸塩（試料Ａ）の１５質量％水分散液に、バインダとしてポリフッ化ビニリデンを試料Ａに対して５質量％となるよう添加した特定アルミニウムケイ酸塩分散液を、上記正極シート上にドクターブレード法によって塗布し、１２０℃で真空乾燥させ、正極Ａを作製した。正極Ａにおける試料Ａの付与量は５ｇ／ｍ２であった。 Specified aluminum silicate dispersion obtained by adding polyvinylidene fluoride as a binder to 15% by mass aqueous dispersion of the specific aluminum silicate (sample A) prepared in Example 1 to 5% by mass with respect to sample A Was applied onto the positive electrode sheet by a doctor blade method and vacuum dried at 120 ° C. to prepare a positive electrode A. The amount of sample A applied to the positive electrode A was 5 g / m 2 .
＜負極の作製＞
　負極は以下の方法で作製した。負極活物質として、平均粒径１０μｍの人造黒鉛粉末を用いた。人造黒鉛粉末とポリフッ化ビニリデンを、質量比９０：１０で混合し、有機溶媒として１－メチル－２－ピロリドンを添加して、十分に混練して負極スラリーを調製した。このスラリーを、ドクターブレード法によって、乾燥後の塗布量が７５ｇ／ｍ２となるように厚さ１０μｍの銅箔からなる負極集電体の表面に塗布し、１００℃で２時間乾燥して、負極を作製した。 <Production of negative electrode>
The negative electrode was produced by the following method. Artificial graphite powder having an average particle size of 10 μm was used as the negative electrode active material. Artificial graphite powder and polyvinylidene fluoride were mixed at a mass ratio of 90:10, 1-methyl-2-pyrrolidone was added as an organic solvent, and the mixture was sufficiently kneaded to prepare a negative electrode slurry. This slurry was applied to the surface of a negative electrode current collector made of a copper foil having a thickness of 10 μm by a doctor blade method so that the coating amount after drying was 75 g / m 2, and dried at 100 ° C. for 2 hours. A negative electrode was produced.
＜リチウムイオン二次電池の作製＞
　セパレータとして厚さ２５μｍのポリエチレン製多孔質シートを用い、また、ジエチルカーボネートとエチレンカーボネートの体積比１：１の混合溶媒にＬｉＰＦ６を１ｍｏｌ／ｌの濃度になるように溶解させたものを電解液として用い、アルミラミネートセルを作製した。アルミラミネートセルとは、外装材としてナイロンフィルム－アルミニウム箔－変性ポリオレフィンフィルムからなる三層ラミネートフィルムを用い、その外装材内に前記の正極、負極、セパレータ、電解液などを封入したリチウムイオン二次電池である。 <Production of lithium ion secondary battery>
A polyethylene porous sheet having a thickness of 25 μm was used as a separator, and a solution obtained by dissolving LiPF 6 in a mixed solvent of 1: 1 volume ratio of diethyl carbonate and ethylene carbonate to a concentration of 1 mol / l was used as an electrolytic solution. An aluminum laminate cell was produced. An aluminum laminate cell uses a three-layer laminate film made of nylon film-aluminum foil-modified polyolefin film as an exterior material, and the lithium ion secondary in which the positive electrode, negative electrode, separator, electrolyte, etc. are enclosed in the exterior material. It is a battery.
＜電池特性の測定＞
　上記作製したリチウムイオン二次電池について、下記方法により初期容量、充放電特性、インピーダンスを測定した。その後５０℃の恒温槽に１週間放置した後、再度充放電測定及びインピーダンス測定を行った。 <Measurement of battery characteristics>
About the produced lithium ion secondary battery, the initial stage capacity | capacitance, charging / discharging characteristic, and impedance were measured with the following method. Then, after being left in a thermostatic bath at 50 ° C. for 1 week, charge / discharge measurement and impedance measurement were performed again.
（初期容量の測定）
　作製したリチウムイオン二次電池を充放電測定装置（東洋システム製　ＴＯＳＣＡＴ－３１００）に接続し、活物質の量より算出される、１時間で満充電に達する理論電流値を１Ｃとした時の０．２Ｃの電流値により、４．２Ｖに達するまで定電流で充電し、その後電流値が０．０１ｍＡとなるまで４．２Ｖで定電圧充電を行った。充電終了後に３０分静置した後、０．２Ｃの電流値でリチウムイオン二次電池が３Ｖに達するまで定電流放電を行った。放電終了後は次の充電まで３０分静置した。上記の操作を２回行った時の２回目の放電容量をその電池の放電容量とした。 (Measurement of initial capacity)
Connected the prepared lithium ion secondary battery to a charge / discharge measuring device (TOSCAT-3100 manufactured by Toyo System Co., Ltd.), calculated from the amount of active material, the theoretical current value that reaches full charge in 1 hour is 1C. The battery was charged at a constant current until a current value of 4.2 C reached 4.2 V, and then charged at a constant voltage of 4.2 V until the current value reached 0.01 mA. After standing for 30 minutes after the end of charging, constant current discharge was performed at a current value of 0.2 C until the lithium ion secondary battery reached 3V. After the end of discharging, it was left for 30 minutes until the next charge. The discharge capacity at the second time when the above operation was performed twice was defined as the discharge capacity of the battery.
　試料Ａを正極に塗布したセルは、試料Ａを塗布していないセルと比較して、同様の初期容量を示した。 The cell with sample A applied to the positive electrode showed similar initial capacity compared to the cell without sample A applied.
（充放電特性の測定）
　０．２Ｃの電流値により４．２Ｖに達するまで定電流で充電し、その後電流値が０．０１ｍＡとなるまで４．２Ｖで定電圧充電を行った。充電終了後に３０分静置した後、０．５Ｃの電流値でリチウムイオン二次電池が３Ｖに達するまで定電流放電を行った。同様の充電条件により充電後に１Ｃ、２Ｃ、３Ｃ、５Ｃの電流値で放電容量を測定し、放電容量の放電条件依存性を評価した。 (Measurement of charge / discharge characteristics)
The battery was charged with a constant current until it reached 4.2 V with a current value of 0.2 C, and then was charged with a constant voltage at 4.2 V until the current value reached 0.01 mA. After standing for 30 minutes after the completion of charging, constant current discharge was performed at a current value of 0.5 C until the lithium ion secondary battery reached 3V. The discharge capacity was measured with the current values of 1C, 2C, 3C, and 5C after charging under the same charging conditions, and the dependence of the discharge capacity on the discharge conditions was evaluated.
　試料Ａを正極に塗布したセルは、試料Ａを塗布していないセルと比較して、放電容量の低下率が小さくなった。 The cell in which the sample A was applied to the positive electrode had a lower discharge capacity reduction rate than the cell in which the sample A was not applied.
（インピーダンス測定）
　充放電特性を測定後のリチウムイオン二次電池を３０分静置後、デジタルマルチメーター（北斗電工製　ＨＺ－５０００と周波数応答解析装置を組み合わせたもの）を用いてＣｏｌｅ－Ｃｏｌｅ　Ｐｌｏｔを測定し、代表値として周波数１ｋＨｚにおけるインピーダンスを比較した。 (Impedance measurement)
After leaving the lithium ion secondary battery after measuring the charge / discharge characteristics for 30 minutes, measure the Cole-Cole Plot using a digital multimeter (combined Hokuto Denko HZ-5000 and frequency response analyzer), The impedance at a frequency of 1 kHz was compared as a representative value.
　試料Ａを正極に塗布したセルは、試料Ａを塗布していないセルと比較して、５０℃１週間放置後のインピーダンスの上昇率が小さくなった。 The cell in which the sample A was applied to the positive electrode had a smaller rate of increase in impedance after being left for 1 week at 50 ° C. than the cell in which the sample A was not applied.
　前記の初期容量、充放電特性、インピーダンスの測定結果から、正極表面に付与した試料Ａは、セルの長寿命化や安全性向上に寄与することが確認された。これは、試料Ａのイオン吸着能の評価結果から、正極から溶出した不純物を吸着したことによるものと推測される。 From the measurement results of the initial capacity, charge / discharge characteristics, and impedance, it was confirmed that Sample A applied to the positive electrode surface contributes to the extension of cell life and safety. This is presumed to be due to the adsorption of impurities eluted from the positive electrode from the evaluation results of the ion adsorption ability of sample A.
　本明細書で引用した全ての刊行物、特許および特許出願をそのまま参考として本明細書にとり入れるものとする。 All publications, patents and patent applications cited in this specification shall be incorporated into the present specification as they are.
１０　　第一の特定アルミニウムケイ酸塩
１０ａ　管状体
２０　　内壁
３０　　隙間 10 1st specific aluminum silicate 10a Tubular body 20 Inner wall 30 Crevice

Claims (10)

  1. 　集電体と、前記集電体の上に設けられた正極活物質を含有する層とを有し、前記正極活物質を含有する層の表面に、Ｓｉ及びＡｌの元素モル比Ｓｉ／Ａｌが０．３以上１．０未満のアルミニウムケイ酸塩が付与されてなるリチウムイオン二次電池用正極。 A current collector and a layer containing a positive electrode active material provided on the current collector, and an element molar ratio Si / Al of Si and Al is formed on the surface of the layer containing the positive electrode active material. A positive electrode for a lithium ion secondary battery provided with an aluminum silicate of 0.3 or more and less than 1.0.
  2. 　前記アルミニウムケイ酸塩が、２７Ａｌ－ＮＭＲスペクトルにおいて、３ｐｐｍ近辺にピークを有する請求項１に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to claim 1, wherein the aluminum silicate has a peak in the vicinity of 3 ppm in a 27Al-NMR spectrum.
  3. 　前記アルミニウムケイ酸塩が、２９Ｓｉ－ＮＭＲスペクトルにおいて、－７８ｐｐｍおよび－８５ｐｐｍ近辺にピークを有する請求項１又は請求項２に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to claim 1 or 2, wherein the aluminum silicate has peaks in the vicinity of -78 ppm and -85 ppm in a 29 Si-NMR spectrum.
  4. 　前記アルミニウムケイ酸塩の前記元素モル比Ｓｉ／Ａｌが０．４以上０．６以下である請求項１～請求項３のいずれか１項に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to any one of claims 1 to 3, wherein the element molar ratio Si / Al of the aluminum silicate is 0.4 or more and 0.6 or less.
  5. 　前記アルミニウムケイ酸塩が、Ｘ線源としてＣｕＫα線を用いた粉末Ｘ線回折スペクトルにおいて２θ＝２６．９°及び４０．３°近辺にピークを有し、層状粘土鉱物に由来する２０°及び３５°近辺にはピークを有しない請求項１～請求項４のいずれか１項に記載のリチウムイオン二次電池用正極。 The aluminum silicate has peaks in the vicinity of 2θ = 26.9 ° and 40.3 ° in a powder X-ray diffraction spectrum using CuKα ray as an X-ray source, and 20 ° and 35 derived from a layered clay mineral. The positive electrode for a lithium ion secondary battery according to any one of claims 1 to 4, which has no peak in the vicinity of °.
  6. 　前記アルミニウムケイ酸塩が、２９Ｓｉ－ＮＭＲスペクトルにおける－７８ｐｐｍ近辺のピークＡと、－８５ｐｐｍ近辺のピークＢとの面積比率（ピークＢ／ピークＡ）が、２．０～９．０である請求項３～請求項５のいずれか１項に記載のリチウムイオン二次電池用正極。 In the 29Si-NMR spectrum, the aluminum silicate has an area ratio (peak B / peak A) between a peak A around -78 ppm and a peak B around -85 ppm (2.0 to 9.0). The positive electrode for a lithium ion secondary battery according to any one of claims 3 to 5.
  7. 　前記アルミニウムケイ酸塩のＢＥＴ比表面積が、２５０ｍ２／ｇ以上である請求項１～請求項６のいずれか１項に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to any one of claims 1 to 6, wherein the aluminum silicate has a BET specific surface area of 250 m 2 / g or more.
  8. 　前記アルミニウムケイ酸塩が、前記アルミニウムケイ酸塩を含む分散液によって付与されてなる請求項１～請求項７のいずれか１項に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to any one of claims 1 to 7, wherein the aluminum silicate is provided by a dispersion containing the aluminum silicate.
  9. 　前記分散液が更にバインダを含有する請求項８に記載のリチウムイオン二次電池用正極。 The positive electrode for a lithium ion secondary battery according to claim 8, wherein the dispersion further contains a binder.
  10. 　請求項１～請求項９のいずれか１項に記載のリチウムイオン二次電池用正極と、
    　負極と、
    　電解質と、
    を有するリチウムイオン二次電池。     A positive electrode for a lithium ion secondary battery according to any one of claims 1 to 9,
    A negative electrode,
    Electrolyte,
    A lithium ion secondary battery.
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Publication number Priority date Publication date Assignee Title
JP5879943B2 (en) * 2011-11-15 2016-03-08 日立化成株式会社 Lithium ion secondary battery
WO2016098553A1 (en) * 2014-12-17 2016-06-23 日立化成株式会社 Lithium ion secondary cell
JP6245382B2 (en) * 2014-12-17 2017-12-13 日立化成株式会社 Lithium ion secondary battery
JP6960176B2 (en) * 2018-03-12 2021-11-05 Ａｔｔａｃｃａｔｏ合同会社 Skeleton forming agent, electrodes using it, and method for manufacturing electrodes
JP6678358B2 (en) * 2018-03-12 2020-04-08 Ａｔｔａｃｃａｔｏ合同会社 Skeleton forming agent, electrode using the same, and method for producing electrode
JP6635616B2 (en) * 2018-10-10 2020-01-29 Ａｔｔａｃｃａｔｏ合同会社 Positive electrode for non-aqueous electrolyte secondary battery and battery using the same
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11260416A (en) * 1998-03-11 1999-09-24 Ngk Insulators Ltd Lithium secondary battery
JP2000077103A (en) * 1998-08-31 2000-03-14 Hitachi Ltd Lithium secondary battery and apparatus
JP2001064010A (en) * 1999-08-30 2001-03-13 Agency Of Ind Science & Technol Synthetic method of tubular aluminum silicate from high concentration inorganic solution
JP2008179533A (en) * 2006-12-27 2008-08-07 National Institute Of Advanced Industrial & Technology Amorphous aluminum silicate having excellent moisture adsorption/desorption characteristics in medium humidity range
WO2009084632A1 (en) * 2007-12-27 2009-07-09 National Institute Of Advanced Industrial Science And Technology Aluminum silicate complex, and high-performance adsorbent comprising the same
JP2012146477A (en) * 2011-01-12 2012-08-02 Hitachi Ltd Nonaqueous electrolyte battery
WO2012124222A1 (en) * 2011-03-11 2012-09-20 日立化成工業株式会社 Aluminum silicate, metal ion adsorbent, and method for producing same

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11260416A (en) * 1998-03-11 1999-09-24 Ngk Insulators Ltd Lithium secondary battery
JP2000077103A (en) * 1998-08-31 2000-03-14 Hitachi Ltd Lithium secondary battery and apparatus
JP2001064010A (en) * 1999-08-30 2001-03-13 Agency Of Ind Science & Technol Synthetic method of tubular aluminum silicate from high concentration inorganic solution
JP2008179533A (en) * 2006-12-27 2008-08-07 National Institute Of Advanced Industrial & Technology Amorphous aluminum silicate having excellent moisture adsorption/desorption characteristics in medium humidity range
WO2009084632A1 (en) * 2007-12-27 2009-07-09 National Institute Of Advanced Industrial Science And Technology Aluminum silicate complex, and high-performance adsorbent comprising the same
JP2012146477A (en) * 2011-01-12 2012-08-02 Hitachi Ltd Nonaqueous electrolyte battery
WO2012124222A1 (en) * 2011-03-11 2012-09-20 日立化成工業株式会社 Aluminum silicate, metal ion adsorbent, and method for producing same

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