Activated carbon and method for manufacturing same, and activated carbon electrode and method for manufacturing same

Abstract

An activated carbon wherein, in a cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by a BJH method, the absolute value of the difference between pore diameters yielding volumes of 25% and 75% is 5.00 to 0.60 nm, and the average pore diameter is 5.0 to 1.5 nm. An activated carbon electrode containing activated carbon in which, in a cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by a BJH method, the absolute value of the difference between pore diameters yielding volumes of 25% and 75% is 5.00 to 0.60 nm, and not containing a binder.

Description

Activated carbon and its manufacturing method, as well as activated carbon electrodes and their manufacturing method.

[0001] The present invention relates to activated carbon, a method for producing the same, and an activated carbon electrode and a method for producing the same.

[0002] Activated carbon is a porous carbon material with micropores, and due to its large specific surface area and adsorption capacity, it is used for applications such as the adsorption and separation of trace components. In recent years, activated carbon has also attracted attention as a battery material, and its applications are being developed, for example, as an electrode material for air batteries and as a polarizing electrode material for electric double-layer capacitors (EDLCs). An EDLC is a capacitor that utilizes the capacitance accumulated in the electric double layer formed at the interface between the polarizing electrode and the electrolyte. The structure of an EDLC consists of a pair of polarizing electrodes separated by a separator, a case to house them, an electrolyte, and a current collector.

[0003] The raw materials for activated carbon used as polarizing electrode material include, for example, plant materials such as coconut shells and cellulose, petroleum materials such as coal and petroleum pitch, and resins such as phenolic resins and polyacrylonitrile (PAN). On the other hand, for the electrolyte, aqueous solutions such as sulfuric acid aqueous solution and potassium hydroxide aqueous solution are often used, while for organic solvent systems, electrolytes such as propylene carbonate (PC) in which quaternary onium salts are dissolved are often used. Aqueous EDLCs using aqueous electrolytes are suitable for low equivalent series resistance (ESR) due to the high conductivity of the electrolyte and have excellent environmental characteristics as they are not affected by humidity. Organic EDLCs using organic electrolytes have the advantage of high energy density due to their high voltage resistance and can be miniaturized.

[0004] In recent years, various polarizable electrode materials using activated carbon have been proposed. For example, Patent Document 1 proposes an activated carbon electrode in which the capacitance per unit volume of the electrode is improved when polyvinylidene chloride resin is used as the carbonaceous raw material for activated carbon, and an electric double-layer capacitor with a large capacitance equipped with the activated carbon electrode as a polarizable electrode. Specifically, the pore volume is 0.250 cm³. ３An activated carbon electrode formed using activated carbon obtained by carbonizing and / or activating polyvinylidene chloride resin powder with a concentration of less than / g, and an electric double-layer capacitor equipped with the activated carbon electrode as a polarizing electrode have been proposed.

[0005] Furthermore, for example, Patent Document 2 proposes a spherical carbon material for aqueous EDLC electrodes with a particle size of 500 μm or less that exhibits excellent processability and provides high capacitance in the high discharge current density region. Specifically, it proposes a porous carbon material having numerous pores, in which the median pore diameter of the pore distribution obtained by gas adsorption using carbon dioxide gas is 1 Å to 8.4 Å or 9.3 Å to 12.4 Å, and the peak differential pore volume is 0.073 cc / (g·Å) or more, and the spherical carbon material for aqueous EDLC electrodes with a particle size of 500 μm or less.

[0006] Japanese Patent No. 4394208, Japanese Unexamined Patent Publication No. 2003-173941

[0007] However, when coconut shells, a common raw material for activated carbon, are used, the production of activated carbon requires treatment with sulfuric acid or alkali metal hydroxide, making it inefficient. Furthermore, electric double-layer capacitors equipped with polarizable electrodes formed from such activated carbon generally do not have sufficient capacitance per unit volume. Additionally, the activated carbon described in Patent Document 1 uses polyvinylidene chloride resin as a raw material, which generates hydrogen halides during production, leading to rust on the manufacturing equipment. Moreover, a binder is usually required when producing activated carbon electrodes, making it inefficient. Furthermore, the carbon material for aqueous EDLC electrodes described in Patent Document 2, when using activated carbon made from polyvinylidene chloride resin as a raw material, forms numerous micropores with a sharp pore distribution. However, water molecules and other substances are adsorbed into the ultramicropores, resulting in low capacitance in non-aqueous EDLCs, and there is room for improvement.

[0008] Therefore, the present invention aims to efficiently provide high-performance activated carbon and high-performance activated carbon electrodes.

[0009] As a result of diligent research, the inventors discovered that activated carbon with a specific configuration and activated carbon electrodes with a specific configuration can solve the above problems, and thus completed the present invention.

[0010] In other words, the present invention relates, for example, to the following: [1] Activated carbon in which, in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method, the absolute value of the difference in pore diameters that give volumes 25% and 75% is 5.00 to 0.60 nm, and the average pore diameter is 5.0 to 1.5 nm. [2] CO ２ Gas adsorption capacity is 64 cm ３ [1] Activated carbon having a strength of 1 / g or more. [3] Activated carbon having a Raman D band full width at half maximum of 150 or more. [4] Activated carbon having a Raman D / G band area ratio of 2.7 or more. [5] Activated carbon having a Raman G band full width at half maximum of 64.0 to 41.5. [6] Activated carbon having a Raman D / G band peak intensity ratio of 0.99 or less. [7] Activated carbon having a specific surface area of ​​1150 to 3550 m². ２[1] to [6]. [8] Activated carbon according to any one of [1] to [7], wherein the residual chlorine concentration calculated by X-ray fluorescence is 5.0% by mass or less. [9] Activated carbon according to any one of [1] to [8], comprising a carbonizing and / or activating substance for halogenated resins, or a carbonizing and / or activating substance for halogenated resin molded articles.

[10] Activated carbon according to [9], wherein the halogenated resin or halogenated resin molded article comprises a hydrogen halide neutralizing agent.

[11] Activated carbon according to [9] or

[10] , wherein the halogenated resin in the halogenated resin or halogenated resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

[12] Activated carbon electrode comprising the activated carbon according to any one of [1] to

[11] and a binder.

[13] An electric double-layer capacitor comprising the activated carbon electrode described in

[12] as a polarizing electrode.

[14] A lithium-ion capacitor comprising the activated carbon electrode described in

[12] as a polarizing electrode.

[15] A method for producing activated carbon, comprising the steps of carbonizing and / or activating a halogen-based resin, or carbonizing and / or activating a halogen-based resin molded article.

[16] The method for producing activated carbon according to

[15] , wherein the halogen-based resin or the halogen-based resin molded article comprises a hydrogen halide neutralizing agent.

[17] The method for producing activated carbon according to

[15] or

[16] , wherein the halogen-based resin in the halogen-based resin or the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

[18] An activated carbon electrode containing activated carbon, which does not contain a binder, and in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method, the absolute value of the difference in pore diameters that give volumes 25% and 75% is 5.00 to 0.60 nm.

[19] The CO of the activated carbon ２ Gas adsorption capacity is 64 cm ３

[18] or greater.

[20] An activated carbon electrode according to

[18] or

[19] , wherein the half width at half maximum of the Raman D band of the activated carbon is 150 or greater.

[21] An activated carbon electrode according to any one of

[18] to

[20] , wherein the area ratio of the Raman D / G band of the activated carbon is 2.7 or greater.

[22] An activated carbon electrode according to any one of

[18] to

[21] , wherein the half width at half maximum of the Raman G band of the activated carbon is 64.0 to 41.5.

[23] An activated carbon electrode according to any one of

[18] to

[22] , wherein the peak intensity ratio of the Raman D / G band of the activated carbon is 0.99 or less.

[24] The specific surface area of ​​the activated carbon is 1150 to 3550 m². ２

[18] to

[23] , wherein the activated carbon electrode is

[25] / g.

[26] The activated carbon electrode according to any one of

[18] to

[25] , wherein the average pore size of the activated carbon calculated by the BJH method is 5.0 to 1.5.

[27] The activated carbon electrode according to any one of

[18] to

[26] , wherein the residual chlorine concentration of the activated carbon calculated by the X-ray fluorescence method is 5.0% by mass or less.

[28] The activated carbon electrode according to any one of

[18] to

[26] , wherein the activated carbon contains a carbonizing and / or activating substance for halogenated resins, or a carbonizing and / or activating substance for halogenated resin molded articles.

[29] The activated carbon electrode according to

[27] , wherein the halogenated resin or halogenated resin molded article contains a hydrogen halide neutralizing agent.

[29] The activated carbon electrode according to

[27] or

[28] , wherein the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

[30] An electric double-layer capacitor comprising the activated carbon electrode according to any one of

[18] to

[29] as a polarizing electrode.

[31] A lithium-ion capacitor comprising the activated carbon electrode according to any one of

[18] to

[29] as a polarizing electrode.

[32] A method for producing an activated carbon electrode, comprising the steps of: obtaining activated carbon by carbonizing and / or activating a halogen-based resin, or obtaining activated carbon by carbonizing and / or activating a halogen-based resin molded article; and obtaining an activated carbon electrode by molding the obtained activated carbon without using a binder.

[33] The method for producing an activated carbon electrode according to

[32] , wherein the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent.

[34] The method for producing an activated carbon electrode according to

[32] or

[33] , wherein the halogen resin or the halogen resin in the halogen resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

[0011] According to the present invention, high-performance activated carbon and high-performance activated carbon electrodes can be efficiently provided.

[0012] This is an example of the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method. It is a graph showing the voltage curve when constant current discharge is performed after charging an electric double layer capacitor, as well as the relationship between the change in electrode voltage and the time required for the change.

[0013] Hereinafter, a mode for carrying out the present invention (hereinafter abbreviated as "the present embodiment") will be described in detail. The following embodiments are exemplifications for explaining the present invention, and the present invention is not limited thereto. That is, the present invention can be arbitrarily modified and implemented without departing from the scope of its gist.

[0014] [Activated carbon] The activated carbon of the present embodiment has an absolute value of the difference between the pore diameters giving volumes of 25% and 75% of 5.00 to 0.60 nm in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method, and has an average pore diameter of 5.0 to 1.5 nm. With such characteristics, the activated carbon of the present embodiment has high performance, and for example, when used as an activated carbon electrode, it is suitable as a polarizable electrode for electric double layer capacitors, lithium ion capacitors and the like.

[0015] In the activated carbon of the present embodiment, in the cumulative pore volume distribution calculated by the BJH method, the absolute value of the difference between the pore diameters giving volumes of 25% and 75% is 5.00 to 0.60 nm, preferably 3.00 to 0.60 nm, more preferably 2.00 to 0.60 nm, and still more preferably 1.50 to 0.60 nm. The method for obtaining activated carbon in which the absolute value of the difference between the pore diameters giving volumes of 25% and 75% in the cumulative pore volume distribution calculated by the BJH method falls within the above range is not particularly limited, and for example, a method using a halogen-based resin as a raw material can be mentioned. In the present embodiment, the absolute value of the difference between the pore diameters giving volumes of 25% and 75% in the cumulative pore volume distribution can be specifically measured by the method described in the examples below.

[0016] The activated carbon of the present embodiment has CO ２ gas adsorption capacity of 64.00 cm ３ / g or more, preferably 64.00 cm ３ / g or more and 76.70 cm３ It is more preferable that the amount be less than or equal to 70.00 cm². ３ / g or more, 76.70cm ３ It is even more preferable that it be less than or equal to 74.50 cm². ３ / g or more, 76.70cm ３ It is even more preferable that the amount be less than or equal to 75.40 cm². ３ / g or more, 76.70cm ３ It is particularly preferable that the amount is less than or equal to / g. The activated carbon of this embodiment is CO ２ When the gas adsorption performance is within the aforementioned range, it tends to become even more high-performance. Activated carbon CO ２ The method for controlling the gas adsorption performance within the above range is not particularly limited, but for example, by controlling the average pore size of the activated carbon, CO ２ One method is to adjust the average pore size to be suitable for gas adsorption. In this embodiment, the activated carbon is CO ２ The gas adsorption performance can be measured by the method described in the examples below.

[0017] In this embodiment, the activated carbon preferably has a Raman D band full width at half maximum (FWHM) of 150.00 or more, more preferably 150.00 or more and 181.00 or less, even more preferably 165.00 or more and 181.00 or less, even more preferably 174.00 or more and 181.00 or less, and particularly preferably 177.00 or more and 181.00 or less. The activated carbon of this embodiment tends to perform even better when the Raman D band FWHM is within the above range. There are no particular limitations on the method for controlling the Raman D band FWHM of the activated carbon to be within the above range, but one example is a method of creating physical defects in the graphite structure by forming pores. In this embodiment, the Raman D band FWHM of the activated carbon can be measured by the method described in the later examples.

[0018] In this embodiment, the activated carbon preferably has a Raman D / G band area ratio of 2.70 or more, more preferably 2.70 or more and 2.96 or less, even more preferably 2.82 or more and 2.96 or less, even more preferably 2.91 or more and 2.96 or less, and particularly preferably 2.93 or more and 2.96 or less. The activated carbon of this embodiment tends to perform even better when the Raman D / G band area ratio is within the above range. There are no particular limitations on the method for controlling the Raman D / G band area ratio of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature to increase the crystallinity of the graphite structure. In this embodiment, the Raman D / G band area ratio of the activated carbon can be measured by the method described in the examples below.

[0019] In this embodiment, the activated carbon preferably has a Raman G band full width at half maximum (FWHM) of 64.0 to 41.5. The activated carbon in this embodiment tends to perform even better when the Raman G band FWHM is within the above range. There are no particular limitations on the method for controlling the Raman G band FWHM of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature to increase the crystallinity of the graphite structure. In this embodiment, the Raman G band FWHM of the activated carbon can be measured by the method described in the examples below.

[0020] In this embodiment, the activated carbon preferably has a Raman D / G band peak intensity ratio of 0.995 or less, more preferably 0.868 or more and 0.995 or less, even more preferably 0.868 or more and 0.930 or less, even more preferably 0.868 or more and 0.895 or less, and particularly preferably 0.868 or more and 0.883 or less. The activated carbon of this embodiment tends to perform even better when the Raman D / G band peak intensity ratio is within the above range. There are no particular limitations on the method for controlling the Raman D / G band peak intensity ratio of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature and increase the proportion of graphite structure. In this embodiment, the Raman D / G band peak intensity ratio of the activated carbon can be measured by the method described in the examples below.

[0021] The activated carbon of this embodiment has a specific surface area of ​​1150 to 3550 m². ２ It is preferably / g, and 1700 to 3550m ２ It is more preferable that the amount is / g, and the amount is 2450 to 3550 m ２ It is even more preferable that the amount be / g, and 3000 to 3550 m ２ It is even more preferable that the concentration is / g. The activated carbon of this embodiment tends to perform even better when its specific surface area is within the above range. The method for controlling the specific surface area of ​​the activated carbon to be within the above range is not particularly limited, but examples include methods of activating the activated carbon. In this embodiment, the specific surface area of ​​the activated carbon can be measured by the method described in the examples below.

[0022] In this embodiment, the activated carbon preferably has an average pore diameter of 5.00 to 1.50 nm, more preferably 3.00 to 1.50 nm, even more preferably 2.00 to 1.50 nm, and even more preferably 1.70 to 1.50 nm, as calculated by the BJH method. The activated carbon of this embodiment exhibits high performance when its average pore diameter is within the above range. The method for controlling the average pore diameter of the activated carbon calculated by the BJH method to be within the above range is not particularly limited, but examples include methods for activating the activated carbon. In this embodiment, the average pore diameter can be specifically measured by the method described in the examples below.

[0023] In this embodiment, the activated carbon preferably has a residual chlorine concentration of 5.0000% by mass or less, more preferably 0.0010% by mass or more and 5.0000% by mass or less, even more preferably 0.0010% by mass or more and 0.0200% by mass or less, even more preferably 0.0010% by mass or more and 0.0055% by mass or less, particularly preferably 0.0010% by mass or more and 0.0025% by mass or less, and extremely preferably 0.0010% by mass or more and 0.0020% by mass or less. The activated carbon of this embodiment tends to perform even better when the residual chlorine concentration is within the above range. The method for controlling the residual chlorine concentration of the activated carbon, calculated by X-ray fluorescence, to be within the above range is not particularly limited, but for example, a method of neutralizing and removing chlorine with a neutralizing agent such as calcium carbonate can be used. In this embodiment, the residual chlorine concentration can be measured specifically by the method described in the examples below.

[0024] The activated carbon of this embodiment preferably contains a carbonizing and / or activating substance for halogenated resins, or a carbonizing and / or activating substance for halogenated resin molded articles. Activated carbon containing a carbonizing and / or activating substance for halogenated resins tends to be efficiently produced without the need for treatment with sulfuric acid or alkali metal hydroxide during manufacturing.

[0025] Furthermore, it is preferable that the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent. Activated carbon containing a hydrogen halide neutralizing agent can suppress rust on manufacturing equipment caused by the generation of hydrogen halides. In addition, activated carbon obtained by carbonizing the hydrogen halide neutralizing agent and the halogen-based resin together provides a carbon dioxide activation effect and forms sharper pores. In the halogen-based resin or the halogen-based resin molded article, the content of the hydrogen halide neutralizing agent is preferably 0.1% by mass or more, more preferably 0.1 to 91.0% by mass, even more preferably 50.0 to 91.0% by mass, and particularly preferably 65.0 to 91.0% by mass.

[0026] In this embodiment, the neutralizing agent for hydrogen halides is not particularly limited, but examples include calcium carbonate, magnesium carbonate, potassium carbonate, magnesium hydroxide, calcium hydroxide, sodium hydroxide, potassium hydroxide, iron(II) hydroxide, iron(III) hydroxide, zinc oxide, and calcium oxide. Among these, calcium carbonate, sodium hydroxide, potassium hydroxide, zinc oxide, and calcium hydroxide are preferred, calcium carbonate and zinc oxide are more preferred, and calcium carbonate is particularly preferred. Furthermore, when calcium carbonate is used as the neutralizing agent for hydrogen halides, for example, the calcium component is adsorbed onto the ultramicropores (0.6 nm or less) in the activated carbon electrode, reducing the ultramicropores, and tending to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors.

[0027] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is preferably a polyvinylidene chloride resin, a chlorinated polyethylene resin, a polyvinylidene fluoride resin, a polyvinyl fluoride resin, or a fluorinated polyethylene resin; more preferably a polyvinylidene chloride resin, a vinyl chloride resin, a polyvinylidene fluoride resin, or a polyvinyl fluoride resin; even more preferably a polyvinylidene chloride resin or a polyvinylidene fluoride resin; and particularly preferably a polyvinylidene chloride resin.

[0028] The polyvinylidene chloride resin used in this embodiment is not particularly limited as long as it is a resin containing vinylidene chloride. In addition to vinylidene chloride, one or more monomers copolymerizable with vinylidene chloride may be copolymerized, such as vinyl chloride, acrylic acid esters such as methyl acrylate and butyl acrylate; methacrylic acid esters such as methyl methacrylate and butyl methacrylate; acrylonitrile; vinyl acetate, etc.

[0029] The weight-average molecular weight (Mw) of the polyvinylidene chloride resin used in this embodiment is preferably 80,000 to 200,000, more preferably 90,000 to 180,000, and even more preferably 100,000 to 170,000. When the weight-average molecular weight (Mw) of the polyvinylidene chloride resin is within the above range, it tends to maintain the shape of the carbonized precursor in powder form or molded form even when the polyvinylidene chloride resin is thermally decomposed and carbonized. In this embodiment, the carbonized precursor is the original substance before carbonization (carbonization), and refers to halogenated resin or the halogenated resin molded article, etc. A polyvinylidene chloride resin with a weight-average molecular weight within the above range can be obtained, for example, by controlling the charging ratio of vinylidene chloride monomer to vinyl chloride monomer, the amount of polymerization initiator, or the polymerization temperature. In this embodiment, the weight-average molecular weight (Mw) can be determined using gel permeation chromatography (GPC) with a standard polystyrene calibration curve.

[0030] In this embodiment, when the polyvinylidene chloride resin is a copolymer obtained by copolymerizing one or more monomers copolymerizable with vinylidene chloride, the copolymerization ratio of polyvinylidene chloride (constituent units derived from vinylidene chloride) is preferably 70% by mass or more, more preferably 72 to 100% by mass, even more preferably 81 to 100% by mass, even more preferably 85 to 100% by mass, and particularly preferably 85 to 93% by mass, based on the total amount of the polyvinylidene chloride resin. When the copolymerization ratio of polyvinylidene chloride is within the above range, excessive crystallization of the polyvinylidene chloride resin can be suppressed, thereby preventing the pore size from becoming excessively large when carbonized, and the pore size tends to be controlled to a suitable level. Furthermore, it tends to have appropriate flexibility when creating a binderless activated carbon electrode precursor, making it easy to mold.

[0031] [Ratio of constituent units derived from vinylidene chloride and vinyl chloride] The ratio of constituent units derived from vinylidene chloride and vinyl chloride is not particularly limited, but can be measured, for example, using a high-resolution proton nuclear magnetic resonance spectrometer. More specifically, a reprecipitated filtrate of polyvinylidene chloride resin is obtained according to the following procedure. 0.5 g of the sample is dissolved in 10 mL of THF (tetrahydrofuran), and approximately 30 mL of methanol is added to precipitate the resin. The precipitate is then filtered and dried. The reprecipitated filtrate obtained in this way is vacuum dried, and a solution of 5% by mass dissolved in deuterated tetrahydrofuran is measured by H-NMR at a measurement atmosphere of 23±2°C and 50±10% RH (cumulative number of times: 512). The ratio of constituent units derived from vinylidene chloride and the content of constituent units derived from vinyl chloride are calculated using the characteristic chemical shift based on tetramethylsilane in the obtained spectrum.

[0032] The following are constituent units derived from vinylidene chloride (-CH ２ - CCl ２ -) is A, and the constituent unit derived from vinyl chloride (-CH ２ Let -HCl-) be denoted as B, and assign signals 1, 2, and 3 obtained on the spectrum as follows: • Signal 1 (approximately 5.2–4.5 ppm) is assigned to the CH signal of B (methine (CH) group, a constituent unit derived from vinyl chloride). • Signal 2 (approximately 4.2–3.8 ppm) is assigned to the CH2 signal of one of the A's in AA (methylene (CH2) group, a constituent unit derived from vinylidene chloride). • Signal 3 (approximately 3.5–2.8 ppm) is assigned to the CH2 signal of both A's in AB and BA (methylene (CH2) group, a constituent unit derived from vinylidene chloride).

[0033] The mole fractions of each constituent unit were determined from the spectral area values ​​(area of ​​the signal in the NMR spectrum) of these signals. The mole fractions are expressed as follows: • Mole fraction of A (mol%): P(A) • Mole fraction of B (mol%): P(B)

[0034] Based on the area values ​​(peak area in the NMR spectrum) of signals 1, 2, and 3 assigned as described above, the integral values ​​of the signals on the spectrum are assigned as follows: • The integral value of signal 1 (approximately 5.2–4.5 ppm) is equivalent to one 1H of B. • The integral value of signal 2 (approximately 4.2–3.8 ppm) is equivalent to two 1H of A. • The integral value of signal 3 (approximately 3.5–2.8 ppm) is equivalent to four 1H of A.

[0035] The following equation is used to calculate each mole fraction: P(A) + P(B) = 100

[0036] P(A) and P(B) are calculated using the following formulas: • P(B) : P(A) = Integral value of signal 1 : (Integral value of signal 2 + Integral value of signal 3 / 2) / 2 • P(A) = 100 - P(B)

[0037] The constituent unit derived from vinylidene chloride (-CH ２ - CCl ２ The molecular weight of A, which is -), is set to 97.0, and the constituent unit derived from vinyl chloride (-CH ２ Assuming that the molecular weight of B (-HCl-) is 62.5, the following equations hold true, and the mass fractions are calculated using them. Note that each mass fraction is expressed as follows: • Mass fraction of A (mass%): Q(A) • Mass fraction of B (mass%): Q(B) • Q(A) = (P(A) × 97.0) / (P(A) × 97.0 + P(B) × 62.5) × 100 • Q(B) = 100 - Q(A)

[0038] The polyvinylidene chloride resin content is preferably 77% to 94% by mass, and more preferably 85% to 94% by mass, relative to the total amount of the carbonization precursor. By having the polyvinylidene chloride resin content within the above range, the crystallization-inhibiting effect of additives, etc., prevents the pore size from becoming excessively large during carbonization, and tends to allow control to a suitable pore size.

[0039] The method for measuring the content of each component in the carbonization precursor varies depending on the analyte. For example, the content of polyvinylidene chloride resin can be obtained by vacuum drying the re-precipitation filtration product of the carbonization precursor and measuring its mass. On the other hand, the content of epoxidized vegetable oil can be determined using, for example, NMR. Furthermore, the content of citrate esters and dibasic acid esters can be obtained by extracting the additives from the carbonization precursor using an organic solvent such as acetone and analyzing them by gas chromatography.

[0040] In this embodiment, the polyvinylidene chloride resin may contain various additives such as stabilizers, plasticizers, antioxidants, UV absorbers, and lubricants. The polyvinylidene chloride resin also includes resin compositions containing such additives. Furthermore, the resin composition may also contain small amounts of other resins, such as polyvinyl chloride resin or polyacrylonitrile resin.

[0041] The carbonization precursor used in this embodiment may contain various additives in addition to the polyvinylidene chloride resin, as needed. The additives are not particularly limited and include, for example, known stabilizers such as epoxidized vegetable oils, and known plasticizers such as citrate esters, dibasic acid esters, and acetylated fatty acid glycerides.

[0042] <Epoxy Vegetable Oil> The carbonization precursor used in this embodiment preferably contains epoxy vegetable oil from the viewpoint of suppressing color changes of the carbonization precursor. Epoxy vegetable oil also acts as a stabilizer for polyvinylidene chloride resin extrusion processing.

[0043] Epoxidized vegetable oils are not particularly limited, but generally include those produced by epoxidizing edible oils and fats. Specifically, examples include epoxidized soybean oil (hereinafter also referred to as "ESO") and epoxidized linseed oil. Among these, ESO is preferred because it tends to suppress color changes of the carbonization precursor when stored at high temperatures.

[0044] When the carbonization precursor used in this embodiment contains epoxidized vegetable oil, the amount is not particularly limited, but from the viewpoint of suppressing color changes of the carbonization precursor and preventing stickiness due to bleeding, it is preferably 0.5% to 3% by mass, and more preferably 1% to 3% by mass, relative to the total amount of the carbonization precursor. The method for measuring the epoxidized vegetable oil content using NMR follows the procedure below.

[0045] A 50 mg sample is weighed and dissolved in a deuterated solvent (solvent: deuterated THF, internal standard: dimethyl terephthalate, volume: 0.7 mL). A 400 MHz proton NMR (512 cumulative measurements) is performed. The integral ratio is defined as the ratio of the integral value in the 2.23–2.33 ppm range to the integral value in the 8.05–8.11 ppm range. The quantitative value is then calculated using the absolute calibration curve method. Integral ratio = Integral value (2.23–2.33 ppm) / Integral value (8.05–8.11 ppm)

[0046] The carbonization precursor used in this embodiment preferably contains at least one compound selected from the group consisting of citrate esters, dibasic acid esters, and acetylated fatty acid glycerides, from the viewpoint of moldability and other factors. In particular, by including acetylated fatty acid glycerides in the carbonization precursor, the above-mentioned effects of the carbonization precursor in this embodiment tend to become even more pronounced.

[0047] <Citrate Ester> In this embodiment, the citrate ester contained in the polyvinylidene chloride resin is not particularly limited, but examples include triethyl citrate, tributyl citrate, triethyl acetyl citrate, tributyl acetyl citrate (hereinafter also referred to as "ATBC"), and tri-n-(2-ethylhexyl) acetyl citrate. Among these, ATBC is preferred from the viewpoint of having a high plasticizing effect on the polyvinylidene chloride resin, sufficiently plasticizing the resin even in small amounts, and making the above-mentioned effects even more pronounced. The citrate ester content is not particularly limited, but is preferably 3.0% to 8.0% by mass, more preferably 3.5% to 7.0% by mass, and even more preferably 4.0% to 6.6% by mass, relative to the total amount of the carbonization precursor. When the citrate ester content is within the above range, the above-mentioned effects of the carbonization precursor in this embodiment tend to become even more pronounced.

[0048] <Dibasic Acid Esters> In this embodiment, the dibasic acid esters included in the carbonization precursor are not particularly limited, but examples include adipic acid esters such as dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, and dioctyl adipate; azelaic acid esters such as di-2-ethylhexyl azelaic acid and octyl azelaic acid; and sebacate acid esters such as dibutyl sebacate (hereinafter also referred to as "DBS") and di-2-ethylhexyl sebacate. Among these, DBS is preferred from the viewpoint of having a high plasticizing effect on polyvinylidene chloride resins, sufficiently plasticizing the resin even in small amounts, and making the above-mentioned effect even more pronounced. The content of the dibasic acid ester is not particularly limited, but is preferably 3.0% to 8.0% by mass, more preferably 3.0% to 7.0% by mass, and even more preferably 3.0% to 5.5% by mass, relative to the total amount of the carbonization precursor. When the dibasic acid ester content is within the aforementioned range, the mobility of the molecular chains of the polyvinylidene chloride resin increases, leading to a higher plasticizing effect and a tendency for the aforementioned effects to become even more pronounced.

[0049] <Acetylated Fatty Acid Glycerides> In this embodiment, the acetylated fatty acid glycerides included in the carbonization precursor are not particularly limited, but examples include glycerin diacetyl monolaurate. The content of acetylated fatty acid glycerides is not particularly limited, but is preferably 0.5% to 2.8% by mass, more preferably 0.5% to 2.5% by mass, even more preferably 0.5% to 2.1% by mass, even more preferably 0.5% to 1.5% by mass, and particularly preferably 0.5% to 0.8% by mass, relative to the total amount of polyvinylidene chloride resin. When the content of acetylated fatty acid glycerides is within the above range, the mobility of the molecular chains of the polyvinylidene chloride resin increases, which enhances the plasticizing effect and tends to make the above-mentioned effects even more pronounced. The above reasons are presumed and are not limited thereto.

[0050] <Other Compounds> The carbonization precursor used in this embodiment may contain compounds other than the epoxidized vegetable oil, citrate ester, dibasic acid ester, and acetylated fatty acid glyceride (hereinafter referred to as "other compounds"), such as plasticizers, stabilizers, weather resistance improvers, colorants such as dyes or pigments, antifogging agents, antibacterial agents, lubricants, nucleating agents, oligomers such as polyester, polymers such as MBS (methyl methacrylate-butadiene-styrene copolymer), etc.

[0051] The aforementioned plasticizer is not particularly limited, but specifically, examples include dimethyl phthalate, diethyl phthalate, dioctyl phthalate, glycerin, glycerin esters, waxes, liquid paraffin, and phosphate esters.

[0052] The aforementioned stabilizers are not particularly limited, but specifically include, for example, antioxidants such as 2,5-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4'-thiobis-(6-t-butylphenol), 2,2'-methylene-bis-(4-methyl-6-t-butylphenol), octadecyl-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, and 4,4'-thiobis-(6-t-butylphenol); and heat stabilizers such as laurate, myristicate, palmitate, stearate, isostearate, oleate, ricinoleate, 2-ethylhexylate, isodecanoate, neodecanoate, and calcium benzoate.

[0053] The weather resistance improving agent is not particularly limited, but specifically, examples include ultraviolet absorbers such as ethylene-2-cyano-3,3'-diphenyl acrylate, 2-(2'-hydroxy-5'-methylphenyl)benzolytriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)5-chlorobenzotriazole, 2-hydroxy-4-methoxybenzophenone, and 2,2'-dihydroxy-4-methoxybenzophenone.

[0054] The aforementioned colorants such as dyes or pigments are not particularly limited, but specifically include, for example, carbon black, phthalocyanine, quinacridone, indoline, azo pigments, and red iron oxide.

[0055] The anti-fogging agent is not particularly limited, but specifically, examples include glycerin fatty acid esters, sorbitan fatty acid esters, polyoxyethylene fatty acid alcohol ethers, polyoxyethylene glycerin fatty acid esters, and polyoxyethylene sorbitan fatty acid esters.

[0056] The aforementioned antibacterial agent is not particularly limited, but specifically, examples include silver-based inorganic antibacterial agents.

[0057] The lubricant is not particularly limited, but specifically, examples include fatty acid hydrocarbon lubricants such as ethylene bissteramide, butyl stearate, polyethylene wax, paraffin wax, carnauba wax, myristyl myristate, and stearyl stearate, as well as higher fatty acid lubricants, fatty acid amide lubricants, and fatty acid ester lubricants.

[0058] The nucleating agent is not particularly limited, but specifically, examples include phosphate ester metal salts.

[0059] The content of the other compounds is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.1% by mass or less, based on the total amount of the carbonization precursor.

[0060] [Method for producing activated carbon] The method for producing activated carbon in this embodiment includes the steps of carbonizing and / or activating a halogen-based resin to obtain activated carbon, or carbonizing and / or activating a halogen-based resin molded body to obtain activated carbon. By using a halogen-based resin or a halogen-based resin molded body as a raw material in this manner, the method for producing activated carbon in this embodiment eliminates the need for treatment with sulfuric acid or alkali metal hydroxide, etc., during the production of activated carbon, thus improving efficiency.

[0061] Furthermore, in the method for producing activated carbon of this embodiment, it is preferable that the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent. By including a hydrogen halide neutralizing agent in the halogen-based resin or the halogen-based resin molded article, rust on the manufacturing equipment caused by the generation of hydrogen halides can be suppressed. In addition, by carbonizing the hydrogen halide neutralizing agent and the halogen-based resin together, the activated carbon obtained has a carbon dioxide activation effect and forms sharper pores. In the halogen-based resin or the halogen-based resin molded article, the content of the hydrogen halide neutralizing agent is preferably 0.1% by mass or more, more preferably 0.1 to 91.0% by mass, even more preferably 50.0 to 91.0% by mass, and particularly preferably 65.0 to 91.0% by mass.

[0062] In this embodiment, the neutralizing agent for hydrogen halides is not particularly limited, but examples include calcium carbonate, magnesium carbonate, potassium carbonate, magnesium hydroxide, calcium hydroxide, sodium hydroxide, potassium hydroxide, iron(II) hydroxide, iron(III) hydroxide, zinc oxide, and calcium oxide. Among these, calcium carbonate, sodium hydroxide, potassium hydroxide, zinc oxide, and calcium hydroxide are preferred, calcium carbonate and zinc oxide are more preferred, and calcium carbonate is particularly preferred. Furthermore, when calcium carbonate is used as the neutralizing agent for hydrogen halides, for example, the calcium component is adsorbed onto the ultramicropores (0.6 nm or less) in the activated carbon electrode, reducing the ultramicropores, and tending to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors. The mechanism by which such an effect is exhibited is not clear, but the inventors of the present invention deduce the following: First, calcium carbonate reacts with the generated hydrogen halides to neutralize them. The amount of calcium carbonate required for neutralization is preferably about 1 kg per 1 kg of polyvinylidene chloride resin. However, to enhance the carbonation effect, it is preferable to use at least twice the amount of calcium carbonate relative to the polyvinylidene chloride resin. When calcium carbonate is heated, an endothermic reaction occurs at around 600-800°C, decomposing it into calcium oxide and carbon dioxide. Furthermore, the dechlorination reaction of vinylidene chloride is completed by 600°C (under a nitrogen atmosphere). Therefore, vinylidene chloride + calcium carbonate → vinylidene chloride carbon + calcium chloride + CO2 ２ +H ２ The reaction of O proceeds completely. During this process, the vinylidene chloride carbon is converted to CO ２ As a result, the specific surface area tends to increase due to the activation treatment. In addition, in this embodiment, it is preferable to wash off the calcium chloride with water and then dry to obtain activated carbon. In particular, in the obtained activated carbon, CO ２ Gas adsorption capacity: 64 cm ３A concentration of 1 / g or higher is preferable for this effect to manifest. Calcium ions form a hydrated structure, with an ion size of approximately 3 Å. The molecular size of water molecules is also approximately 3 Å, and the adsorption of calcium components onto activated carbon improves the pore size ratio to approximately 20 Å. The resulting activated carbon has a random carbon structure with small crystallite sizes. Such activated carbon tends to have a large D-band full width at half maximum and a large D / G ratio. As a result, the resulting activated carbon electrodes tend to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors.

[0063] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is preferably a polyvinylidene chloride resin, a vinyl chloride resin, a chlorinated polyethylene resin, a polyvinylidene fluoride resin, a polyvinylidene fluoride resin, or a fluorinated polyethylene resin; more preferably a polyvinylidene chloride resin, a vinyl chloride resin, a polyvinylidene fluoride resin, or a polyvinylidene fluoride resin; even more preferably a polyvinylidene chloride resin or a polyvinylidene fluoride resin; and particularly preferably a polyvinylidene chloride resin. In this embodiment, for example, when a polyvinylidene chloride resin is used, the effects of the present invention tend to be further exhibited by utilizing the fact that a cross-linked structure of polyene (meaning a molecular skeleton structure having -C=C- or -C≡C-) is generated when the polyvinylidene chloride resin is dehydrochlorinated with a basic reagent, followed by a heat carbonization treatment.

[0064] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article may be virgin raw material, recycled raw material, or bio-raw material, or any combination thereof. Here, "virgin raw material" refers to primary production raw material that is unused and has no recycling history. "Recycled raw material" refers to raw material obtained by recycling used or recovered materials from the manufacturing process, and includes post-consumer materials (PCR) and post-industrial materials (PIR). Recycled raw material may be obtained by mechanical recycling or chemical recycling. "Bio-raw material" refers to raw material derived from biomass. The ratio of bio-derived materials is not particularly limited.

[0065] The polyvinylidene chloride resin used in the manufacturing method of this embodiment is not particularly limited as long as it contains vinylidene chloride, and may contain one or more monomers copolymerized with vinylidene chloride, such as vinyl chloride, acrylic acid esters such as methyl acrylate and butyl acrylate; methacrylic acid esters such as methyl methacrylate and butyl methacrylate; acrylonitrile; vinyl acetate, etc.

[0066] The weight-average molecular weight (Mw) of the polyvinylidene chloride resin used in this embodiment is preferably 80,000 to 200,000, more preferably 90,000 to 180,000, and even more preferably 100,000 to 170,000. When the weight-average molecular weight (Mw) of the polyvinylidene chloride resin is within the above range, it tends to maintain the shape of the carbonized precursor in powder form or molded form even when the polyvinylidene chloride resin is thermally decomposed and carbonized. A polyvinylidene chloride resin with a weight-average molecular weight within the above range can be obtained, for example, by controlling the charging ratio of vinylidene chloride monomer to vinyl chloride monomer, the amount of polymerization initiator, or the polymerization temperature. In this embodiment, the weight-average molecular weight (Mw) can be determined using a standard polystyrene calibration curve by gel permeation chromatography (GPC).

[0067] In this embodiment, when the polyvinylidene chloride resin is a copolymer obtained by copolymerizing one or more monomers copolymerizable with vinylidene chloride, the copolymerization ratio of polyvinylidene chloride (constituent units derived from vinylidene chloride) is preferably 70% by mass or more, more preferably 72 to 100% by mass, even more preferably 81 to 100% by mass, even more preferably 85 to 100% by mass, and particularly preferably 85 to 93% by mass, based on the total amount of the polyvinylidene chloride resin. When the copolymerization ratio of polyvinylidene chloride is within the above range, excessive crystallization of the polyvinylidene chloride resin can be suppressed, thereby preventing the pore diameter from becoming excessively large when carbonized, and there is a tendency to be able to control it to a suitable pore diameter.

[0068] In the manufacturing method of this embodiment, activated carbon can be obtained by carbonizing and / or activating a halogen-based resin, or by carbonizing and / or activating a halogen-based resin molded body. To obtain activated carbon from a halogen-based resin or halogen-based resin molded body, only carbonization treatment is required, or only activation treatment is required. Of course, the halogen-based resin or halogen-based resin molded body may be carbonized and then activated. Furthermore, the activated carbon obtained by carbonization and / or activation can be subjected to higher-order activation treatments such as secondary activation and tertiary activation as needed. There are no particular restrictions on the carbonization method and the activation method.

[0069] The carbonization method is not particularly limited, but examples include firing a halogen-based resin or a halogen-based resin molded article in an inert gas such as nitrogen gas, carbon dioxide, helium, argon, xenon, neon, carbon monoxide, or combustion exhaust gas. By heating the halogen-based resin or the halogen-based resin in the halogen-based resin molded article (for example, polyvinylidene chloride), dehydrochlorination proceeds to form a polyene structure, and then carbonization occurs. The halogen-based resin or halogen-based resin molded article becomes activated carbon with a sufficient specific surface area simply by thermal decomposition treatment in an inert gas. The thermal decomposition treatment conditions are preferably such that the heat treatment temperature is 500°C or higher, more preferably 500 to 1000°C, even more preferably 600 to 1000°C, even more preferably 700 to 1000°C, particularly preferably 800 to 1000°C, and most preferably 900 to 1000°C.

[0070] Examples of activation methods include gas activation methods using activating gases such as water vapor, carbon dioxide, carbon monoxide, hydrogen halides, and oxygen; and activation methods using the hydrogen halide neutralizing agent mentioned above. The heat treatment conditions vary depending on the type of activation method, but the heat treatment temperature is preferably 850°C or higher, and more preferably 850 to 900°C.

[0071] [First Activated Carbon Electrode] The first activated carbon electrode of this embodiment includes the activated carbon described above and a binder. The first activated carbon electrode of this embodiment is high-performance due to the inclusion of the activated carbon described above. The preferred method for manufacturing the first activated carbon electrode of this embodiment is to knead the activated carbon described above, the binder, and a conductive material as needed, and then mold it into a predetermined electrode shape. In this case, an organic solvent, water, or other solvent (dispersion medium) may be added as needed to form a slurry or paste before molding.

[0072] The binder is not particularly limited, but examples include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinylpyrrolidone, polyimide, and carboxymethylcellulose. The conductive material is not particularly limited, but examples include conductive carbon black, graphite, metal fibers, titanium oxide, and ruthenium oxide. The solvents include water, N-methylpyrrolidone, dimethylformamide, toluene, xylene, methyl ethyl ketone, ethyl acetate, methyl acetate, dimethyl phthalate, ethanol, methanol, and butanol. To improve dispersibility, water-soluble polymers such as polyvinyl alcohol may be added.

[0073] Typical methods for producing polarizing electrodes among activated carbon electrodes include: (1) a method in which a solvent is added to a mixture containing activated carbon, conductive material, etc. to make a mixed slurry, which is then applied to a current collector, or a method in which a current collector plate is immersed in the mixed slurry and dried; and (2) a method in which a solvent is added to a mixture containing activated carbon, conductive material, etc., and kneaded, the resulting paste-like mixture is rolled using a roller to form a sheet, and then the dried sheet is bonded to the surface of a current collector plate via a conductive adhesive, etc., then pressed, and heat-treated and dried.

[0074] [Second Activated Carbon Electrode] The second activated carbon electrode of this embodiment contains activated carbon in which the absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method is 5.00 to 0.60 nm, and does not contain a binder. Due to these characteristics, the second activated carbon electrode of this embodiment is high performance and is suitable as a polarizing electrode for electric double-layer capacitors, lithium-ion capacitors, etc.

[0075] The activated carbon used in the second activated carbon electrode of this embodiment has an absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution calculated by the BJH method being 5.00 to 0.60 nm, preferably 3.00 to 0.60 nm, more preferably 2.00 to 0.60 nm, and even more preferably 1.50 to 0.60 nm. The method for obtaining activated carbon in which the absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution calculated by the BJH method is within the above range is not particularly limited, but for example, a method using a halogen-based resin as a raw material can be mentioned. In this embodiment, the absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution can be specifically measured by the method described in the examples below.

[0076] The activated carbon used in this embodiment is CO ２ Gas adsorption performance is 64.00 cm ３ Preferably, it is 64.00 cm or more. ３ / g or more, 76.70cm ３ It is more preferable that the amount be less than or equal to 70.00 cm². ３ / g or more, 76.70cm ３ It is even more preferable that it be less than or equal to 74.50 cm². ３ / g or more, 76.70cm ３ It is even more preferable that the amount be less than or equal to 75.40 cm². ３ / g or more, 76.70cm ３ It is particularly preferable that the amount is less than or equal to / g. The second activated carbon electrode of this embodiment is made of activated carbon CO ２ When the gas adsorption performance is within the aforementioned range, it tends to become even more high-performance. Activated carbon CO ２ The method for controlling the gas adsorption performance within the above range is not particularly limited, but for example, by controlling the average pore size of the activated carbon, CO ２ One method is to adjust the average pore size to be suitable for gas adsorption. In this embodiment, the activated carbon is CO ２ The gas adsorption performance can be measured by the method described in the examples below.

[0077] The activated carbon used in this embodiment preferably has a Raman D band full width at half maximum (FWHM) of 150.00 or more, more preferably 150.00 or more and 181.00 or less, even more preferably 165.00 or more and 181.00 or less, even more preferably 174.00 or more and 181.00 or less, and particularly preferably 177.00 or more and 181.00 or less. The second activated carbon electrode of this embodiment tends to perform even better when the FWHM of the Raman D band of the activated carbon is within the above range. There are no particular limitations on the method for controlling the FWHM of the Raman D band of the activated carbon to be within the above range, but one example is a method of creating physical defects in the graphite structure by forming pores. In this embodiment, the FWHM of the Raman D band of the activated carbon can be measured by the method described in the later examples.

[0078] The activated carbon used in the second activated carbon electrode of this embodiment preferably has a Raman D / G band area ratio of 2.70 or more, more preferably 2.70 or more and 2.96 or less, even more preferably 2.82 or more and 2.96 or less, even more preferably 2.91 or more and 2.96 or less, and particularly preferably 2.93 or more and 2.96 or less. The second activated carbon electrode of this embodiment tends to perform even better when the Raman D / G band area ratio of the activated carbon is within the above range. There are no particular limitations on the method for controlling the Raman D / G band area ratio of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature and increase the crystallinity of the graphite structure. In this embodiment, the Raman D / G band area ratio of the activated carbon can be measured by the method described in the later examples.

[0079] The activated carbon used in the second activated carbon electrode of this embodiment preferably has a Raman G band full width at half maximum (FWHM) of 64.0 to 41.5. The second activated carbon electrode of this embodiment tends to perform even better when the FWHM of the Raman G band of the activated carbon is within the above range. There are no particular limitations on the method for controlling the FWHM of the Raman G band of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature to increase the crystallinity of the graphite structure. In this embodiment, the FWHM of the Raman G band of the activated carbon can be measured by the method described in the later examples.

[0080] The activated carbon used in the second activated carbon electrode of this embodiment preferably has a Raman D / G band peak intensity ratio of 0.995 or less, more preferably 0.868 or more and 0.995 or less, even more preferably 0.868 or more and 0.930 or less, even more preferably 0.868 or more and 0.895 or less, and particularly preferably 0.868 or more and 0.883 or less. The second activated carbon electrode of this embodiment tends to perform even better when the Raman D / G band peak intensity ratio of the activated carbon is within the above range. There are no particular limitations on the method for controlling the Raman D / G band peak intensity ratio of the activated carbon to be within the above range, but for example, one method is to control the carbonization temperature and increase the proportion of graphite structure. In this embodiment, the Raman D / G band peak intensity ratio of the activated carbon can be measured by the method described in the later examples.

[0081] The activated carbon used in the second activated carbon electrode of this embodiment has a specific surface area of ​​1150 to 3550 m². ２ It is preferably / g, and 1700 to 3550m ２ It is more preferable that the amount is / g, and the amount is 2450 to 3550 m ２ It is even more preferable that the amount be / g, and 3000 to 3550 m ２It is even more preferable that the value is / g. The second activated carbon electrode of this embodiment tends to perform even better when the specific surface area of ​​the activated carbon is within the above range. The method for controlling the specific surface area of ​​the activated carbon to be within the above range is not particularly limited, but examples include methods of activating the activated carbon. In this embodiment, the specific surface area of ​​the activated carbon can be measured by the method described in the later examples.

[0082] The activated carbon used in the second activated carbon electrode of this embodiment preferably has an average pore diameter of 5.00 to 1.50 nm, more preferably 3.00 to 1.50 nm, even more preferably 2.00 to 1.50 nm, and even more preferably 1.70 to 1.50 nm, as calculated by the BJH method. The second activated carbon electrode of this embodiment tends to perform even better when the average pore diameter of the activated carbon calculated by the BJH method is within the above range. There are no particular limitations on the method for controlling the average pore diameter of the activated carbon calculated by the BJH method to be within the above range, but examples include methods for activating the activated carbon. In this embodiment, the average pore diameter can be measured specifically by the method described in the examples below.

[0083] The activated carbon used in the second activated carbon electrode of this embodiment preferably has a residual chlorine concentration of 5.0000% by mass or less, calculated by X-ray fluorescence, more preferably between 0.0010% by mass and 5.0000% by mass, even more preferably between 0.0010% by mass and 0.0200% by mass, even more preferably between 0.0010% by mass and 0.0055% by mass, particularly preferably between 0.0010% by mass and 0.0025% by mass, and most preferably between 0.0010% by mass and 0.0020% by mass. The second activated carbon electrode of this embodiment tends to perform even better when the residual chlorine concentration of the activated carbon is within the above range. The method for controlling the residual chlorine concentration of the activated carbon calculated by X-ray fluorescence within the above range is not particularly limited, but for example, a method of neutralizing and removing chlorine with a neutralizing agent such as calcium carbonate can be used. In this embodiment, the residual chlorine concentration can be measured specifically by the method described in the examples below.

[0084] The activated carbon used in the second activated carbon electrode of this embodiment preferably contains a carbonizing and / or activating substance for halogen-based resins, or a carbonizing and / or activating substance for halogen-based resin molded articles. Activated carbon containing a carbonizing and / or activating substance for halogen-based resins tends to be efficiently produced without the need for treatment with sulfuric acid or alkali metal hydroxide during manufacturing.

[0085] Furthermore, it is preferable that the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent. Activated carbon containing a hydrogen halide neutralizing agent can suppress rust on manufacturing equipment caused by the generation of hydrogen halides. In addition, activated carbon obtained by carbonizing the hydrogen halide neutralizing agent and the halogen-based resin together provides a carbon dioxide activation effect and forms sharper pores. In the halogen-based resin or the halogen-based resin molded article, the content of the hydrogen halide neutralizing agent is preferably 0.1% by mass or more, more preferably 0.1 to 91.0% by mass, even more preferably 50.0 to 91.0% by mass, and particularly preferably 65.0 to 91.0% by mass.

[0086] In this embodiment, the neutralizing agent for hydrogen halides is not particularly limited, but examples include calcium carbonate, magnesium carbonate, potassium carbonate, magnesium hydroxide, calcium hydroxide, sodium hydroxide, potassium hydroxide, iron(II) hydroxide, iron(III) hydroxide, zinc oxide, and calcium oxide. Among these, calcium carbonate, sodium hydroxide, potassium hydroxide, zinc oxide, and calcium hydroxide are preferred, calcium carbonate and zinc oxide are more preferred, and calcium carbonate is particularly preferred. Furthermore, when calcium carbonate is used as the neutralizing agent for hydrogen halides, for example, the calcium component is adsorbed onto the ultramicropores (0.6 nm or less) in the activated carbon electrode, reducing the ultramicropores, and tending to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors.

[0087] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is preferably a polyvinylidene chloride resin, a vinyl chloride resin, a chlorinated polyethylene resin, a polyvinylidene fluoride resin, a polyvinylidene fluoride resin, or a fluorinated polyethylene resin; more preferably a polyvinylidene chloride resin, a vinyl chloride resin, a polyvinylidene fluoride resin, or a polyvinylidene fluoride resin; even more preferably a polyvinylidene chloride resin or a polyvinylidene fluoride resin; and particularly preferably a polyvinylidene chloride resin.

[0088] The polyvinylidene chloride resin used in the second activated carbon electrode of this embodiment is not particularly limited as long as it is a resin containing vinylidene chloride. In addition to vinylidene chloride, one or more monomers copolymerizable with vinylidene chloride may be copolymerized, such as vinyl chloride, acrylic acid esters such as methyl acrylate and butyl acrylate; methacrylic acid esters such as methyl methacrylate and butyl methacrylate; acrylonitrile; vinyl acetate, etc.

[0089] The weight-average molecular weight (Mw) of the polyvinylidene chloride resin used in the second activated carbon electrode of this embodiment is preferably 80,000 to 200,000, more preferably 90,000 to 180,000, and even more preferably 100,000 to 170,000. When the weight-average molecular weight (Mw) of the polyvinylidene chloride resin is within the above range, it tends to maintain the shape of the carbonized precursor, whether in powder form or molded form, even when the polyvinylidene chloride resin is thermally decomposed and carbonized. In this embodiment, the carbonized precursor is the original substance before carbonization (carbonization), and refers to a halogenated resin or a molded halogenated resin, etc. A polyvinylidene chloride resin with a weight-average molecular weight within the above range can be obtained, for example, by controlling the charging ratio of vinylidene chloride monomer to vinyl chloride monomer, the amount of polymerization initiator, or the polymerization temperature. In this embodiment, the weight-average molecular weight (Mw) can be determined using gel permeation chromatography (GPC) with a standard polystyrene calibration curve.

[0090] In this embodiment, when the polyvinylidene chloride resin is a copolymer obtained by copolymerizing one or more monomers copolymerizable with vinylidene chloride, the copolymerization ratio of polyvinylidene chloride (constituent units derived from vinylidene chloride) is preferably 70% by mass or more, more preferably 72 to 100% by mass, even more preferably 81 to 100% by mass, even more preferably 85 to 100% by mass, and particularly preferably 85 to 93% by mass, based on the total amount of the polyvinylidene chloride resin. When the copolymerization ratio of polyvinylidene chloride is within the above range, excessive crystallization of the polyvinylidene chloride resin can be suppressed, thereby preventing the pore size from becoming excessively large when carbonized, and the pore size tends to be controlled to a suitable level. Furthermore, it tends to have appropriate flexibility when creating a binderless activated carbon electrode precursor, making it easy to mold.

[0091] [Ratio of constituent units derived from vinylidene chloride and vinyl chloride] The ratio of constituent units derived from vinylidene chloride and vinyl chloride is not particularly limited, but can be measured, for example, using a high-resolution proton nuclear magnetic resonance spectrometer. More specifically, a reprecipitated filtrate of polyvinylidene chloride resin is obtained according to the following procedure. 0.5 g of the sample is dissolved in 10 mL of THF (tetrahydrofuran), and approximately 30 mL of methanol is added to precipitate the resin. The precipitate is then filtered and dried. The reprecipitated filtrate obtained in this way is vacuum dried, and a solution of 5% by mass dissolved in deuterated tetrahydrofuran is measured by H-NMR at a measurement atmosphere of 23±2°C and 50±10% RH (cumulative number of times: 512). The ratio of constituent units derived from vinylidene chloride and the content of constituent units derived from vinyl chloride are calculated using the characteristic chemical shift based on tetramethylsilane in the obtained spectrum.

[0092] The following are constituent units derived from vinylidene chloride (-CH ２ - CCl ２ -) is A, and the constituent unit derived from vinyl chloride (-CH ２ Let -HCl-) be denoted as B, and assign signals 1, 2, and 3 obtained on the spectrum as follows: • Signal 1 (approximately 5.2–4.5 ppm) is assigned to the CH signal of B (methine (CH) group, a constituent unit derived from vinyl chloride). • Signal 2 (approximately 4.2–3.8 ppm) is assigned to the CH2 signal of one of the A's in AA (methylene (CH2) group, a constituent unit derived from vinylidene chloride). • Signal 3 (approximately 3.5–2.8 ppm) is assigned to the CH2 signal of both A's in AB and BA (methylene (CH2) group, a constituent unit derived from vinylidene chloride).

[0093] The mole fractions of each constituent unit were determined from the spectral area values ​​(area of ​​the signal in the NMR spectrum) of these signals. The mole fractions are expressed as follows: • Mole fraction of A (mol%): P(A) • Mole fraction of B (mol%): P(B)

[0094] Based on the area values ​​(peak area in the NMR spectrum) of signals 1, 2, and 3 assigned as described above, the integral values ​​of the signals on the spectrum are assigned as follows: • The integral value of signal 1 (approximately 5.2–4.5 ppm) is equivalent to one 1H of B. • The integral value of signal 2 (approximately 4.2–3.8 ppm) is equivalent to two 1H of A. • The integral value of signal 3 (approximately 3.5–2.8 ppm) is equivalent to four 1H of A.

[0095] The following equation is used to calculate each mole fraction: P(A) + P(B) = 100

[0096] P(A) and P(B) are calculated using the following formulas: • P(B) : P(A) = Integral value of signal 1 : (Integral value of signal 2 + Integral value of signal 3 / 2) / 2 • P(A) = 100 - P(B)

[0097] The constituent unit derived from vinylidene chloride (-CH ２ - CCl ２ The molecular weight of A, which is -), is set to 97.0, and the constituent unit derived from vinyl chloride (-CH ２ Assuming that the molecular weight of B (-HCl-) is 62.5, the following equations hold true, and the mass fractions are calculated using them. Note that each mass fraction is expressed as follows: • Mass fraction of A (mass%): Q(A) • Mass fraction of B (mass%): Q(B) • Q(A) = (P(A) × 97.0) / (P(A) × 97.0 + P(B) × 62.5) × 100 • Q(B) = 100 - Q(A)

[0098] The polyvinylidene chloride resin content is preferably 77% to 94% by mass, and more preferably 85% to 94% by mass, relative to the total amount of the carbonization precursor. By having the polyvinylidene chloride resin content within the above range, the crystallization-inhibiting effect of additives, etc., prevents the pore size from becoming excessively large during carbonization, and tends to allow control to a suitable pore size.

[0099] The method for measuring the content of each component in the carbonization precursor varies depending on the analyte. For example, the content of polyvinylidene chloride resin can be obtained by vacuum drying the re-precipitation filtration product of the carbonization precursor and measuring its mass. On the other hand, the content of epoxidized vegetable oil can be determined using, for example, NMR. Furthermore, the content of citrate esters and dibasic acid esters can be obtained by extracting the additives from the carbonization precursor using an organic solvent such as acetone and analyzing them by gas chromatography.

[0100] In this embodiment, the polyvinylidene chloride resin may contain various additives such as stabilizers, plasticizers, antioxidants, UV absorbers, and lubricants. The polyvinylidene chloride resin also includes resin compositions containing such additives. Furthermore, the resin composition may also contain small amounts of other resins, such as polyvinyl chloride resin or polyacrylonitrile resin.

[0101] The carbonization precursor used in the second activated carbon electrode of this embodiment may contain various additives in addition to the vinylidene chloride resin, as needed. The additives are not particularly limited and include, for example, known stabilizers such as epoxidized vegetable oils, and known plasticizers such as citrate esters, dibasic acid esters, and acetylated fatty acid glycerides.

[0102] <Epoxy Vegetable Oil> The carbonization precursor used in the second activated carbon electrode of this embodiment preferably contains epoxy vegetable oil from the viewpoint of suppressing color changes of the carbonization precursor. Epoxy vegetable oil also acts as a stabilizer for polyvinylidene chloride resin extrusion processing.

[0103] Epoxidized vegetable oils are not particularly limited, but generally include those produced by epoxidizing edible oils and fats. Specifically, examples include epoxidized soybean oil (hereinafter also referred to as "ESO") and epoxidized linseed oil. Among these, ESO is preferred because it tends to suppress color changes of the carbonization precursor when stored at high temperatures.

[0104] When the carbonization precursor used in the second activated carbon electrode of this embodiment contains epoxidized vegetable oil, the amount is not particularly limited, but from the viewpoint of suppressing color changes of the carbonization precursor and preventing stickiness due to bleeding, it is preferably 0.5% to 3% by mass, and more preferably 1% to 3% by mass, relative to the total amount of the carbonization precursor. The method for measuring the epoxidized vegetable oil content using NMR follows the procedure below.

[0105] A 50 mg sample is weighed and dissolved in a deuterated solvent (solvent: deuterated THF, internal standard: dimethyl terephthalate, volume: 0.7 mL). A 400 MHz proton NMR (512 cumulative measurements) is performed. The integral ratio is defined as the ratio of the integral value in the 2.23–2.33 ppm range to the integral value in the 8.05–8.11 ppm range. The quantitative value is then calculated using the absolute calibration curve method. Integral ratio = Integral value (2.23–2.33 ppm) / Integral value (8.05–8.11 ppm)

[0106] The carbonization precursor used in the second activated carbon electrode of this embodiment preferably contains at least one compound selected from the group consisting of citrate esters, dibasic acid esters, and acetylated fatty acid glycerides, from the viewpoint of moldability and other factors. In particular, by including acetylated fatty acid glycerides in the carbonization precursor, the above-mentioned effects of the carbonization precursor of this embodiment tend to become even more pronounced.

[0107] <Citrate Esters> In this embodiment, the citrate esters contained in the polyvinylidene chloride resin are not particularly limited, but examples include triethyl citrate, tributyl citrate, triethyl acetyl citrate, tributyl acetyl citrate (hereinafter also referred to as "ATBC"), and tri-n-(2-ethylhexyl) acetyl citrate. Among these, ATBC is preferred from the viewpoint of having a high plasticizing effect on the vinylidene chloride resin, sufficiently plasticizing the resin even in small amounts, and making the above-mentioned effects even more pronounced. The citrate ester content is not particularly limited, but is preferably 3.0% to 8.0% by mass, more preferably 3.5% to 7.0% by mass, and even more preferably 4.0% to 6.6% by mass, relative to the total amount of the carbonization precursor. When the citrate ester content is within the above range, the above-mentioned effects of the carbonization precursor used in this embodiment tend to become even more pronounced.

[0108] <Dibasic Acid Esters> In this embodiment, the dibasic acid esters included in the carbonization precursor are not particularly limited, but examples include adipic acid esters such as dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, and dioctyl adipate; azelaic acid esters such as di-2-ethylhexyl azelaic acid and octyl azelaic acid; and sebacate acid esters such as dibutyl sebacate (hereinafter also referred to as "DBS") and di-2-ethylhexyl sebacate. Among these, DBS is preferred from the viewpoint of having a high plasticizing effect on vinylidene chloride resins, sufficiently plasticizing the resin even in small amounts, and making the above-mentioned effect even more pronounced. The content of the dibasic acid ester is not particularly limited, but is preferably 3.0% to 8.0% by mass, more preferably 3.0% to 7.0% by mass, and even more preferably 3.0% to 5.5% by mass, relative to the total amount of the carbonization precursor. When the dibasic acid ester content is within the aforementioned range, the mobility of the molecular chains of the polyvinylidene chloride resin increases, leading to a higher plasticizing effect and a tendency for the aforementioned effects to become even more pronounced.

[0109] <Acetylated Fatty Acid Glycerides> In this embodiment, the acetylated fatty acid glycerides included in the carbonization precursor are not particularly limited, but examples include glycerin diacetyl monolaurate. The content of acetylated fatty acid glycerides is not particularly limited, but is preferably 0.5% to 2.8% by mass, more preferably 0.5% to 2.5% by mass, even more preferably 0.5% to 2.1% by mass, even more preferably 0.5% to 1.5% by mass, and particularly preferably 0.5% to 0.8% by mass, relative to the total amount of polyvinylidene chloride resin. When the content of acetylated fatty acid glycerides is within the above range, the mobility of the molecular chains of the polyvinylidene chloride resin increases, which enhances the plasticizing effect and tends to make the above-mentioned effects even more pronounced. The above reasons are presumed and are not limited thereto.

[0110] <Other Compounds> The carbonization precursor used in the second activated carbon electrode of this embodiment may contain compounds other than the epoxidized vegetable oil, citrate ester, dibasic acid ester, and acetylated fatty acid glyceride (hereinafter referred to as "other compounds"), such as plasticizers, stabilizers, weather resistance improvers, colorants such as dyes or pigments, antifogging agents, antibacterial agents, lubricants, nucleating agents, oligomers such as polyester, polymers such as MBS (methyl methacrylate-butadiene-styrene copolymer), etc.

[0111] The aforementioned plasticizer is not particularly limited, but specifically, examples include dimethyl phthalate, diethyl phthalate, dioctyl phthalate, glycerin, glycerin esters, waxes, liquid paraffin, and phosphate esters.

[0112] The aforementioned stabilizers are not particularly limited, but specifically include, for example, antioxidants such as 2,5-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4'-thiobis-(6-t-butylphenol), 2,2'-methylene-bis-(4-methyl-6-t-butylphenol), octadecyl-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, and 4,4'-thiobis-(6-t-butylphenol); and heat stabilizers such as laurate, myristicate, palmitate, stearate, isostearate, oleate, ricinoleate, 2-ethylhexylate, isodecanoate, neodecanoate, and calcium benzoate.

[0113] The weather resistance improving agent is not particularly limited, but specifically, examples include ultraviolet absorbers such as ethylene-2-cyano-3,3'-diphenyl acrylate, 2-(2'-hydroxy-5'-methylphenyl)benzolytriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)5-chlorobenzotriazole, 2-hydroxy-4-methoxybenzophenone, and 2,2'-dihydroxy-4-methoxybenzophenone.

[0114] The aforementioned colorants such as dyes or pigments are not particularly limited, but specifically include, for example, carbon black, phthalocyanine, quinacridone, indoline, azo pigments, and red iron oxide.

[0115] The anti-fogging agent is not particularly limited, but specifically, examples include glycerin fatty acid esters, sorbitan fatty acid esters, polyoxyethylene fatty acid alcohol ethers, polyoxyethylene glycerin fatty acid esters, and polyoxyethylene sorbitan fatty acid esters.

[0116] The aforementioned antibacterial agent is not particularly limited, but specifically, examples include silver-based inorganic antibacterial agents.

[0117] The lubricant is not particularly limited, but specifically, examples include fatty acid hydrocarbon lubricants such as ethylene bissteramide, butyl stearate, polyethylene wax, paraffin wax, carnauba wax, myristyl myristate, and stearyl stearate, as well as higher fatty acid lubricants, fatty acid amide lubricants, and fatty acid ester lubricants.

[0118] The nucleating agent is not particularly limited, but specifically, examples include phosphate ester metal salts.

[0119] The content of the other compounds is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.1% by mass or less, based on the total amount of the carbonization precursor.

[0120] [Method for Manufacturing a Second Activated Carbon Electrode] The method for manufacturing a second activated carbon electrode according to this embodiment includes the steps of obtaining activated carbon by carbonizing and / or activating a halogen-based resin, or by carbonizing and / or activating a halogen-based resin molded body, and obtaining an activated carbon electrode by molding the obtained activated carbon without using a binder. The method for manufacturing a second activated carbon electrode according to this embodiment is efficient because, by using a halogen-based resin or a halogen-based resin molded body as a raw material, treatment with sulfuric acid or alkali metal hydroxide is unnecessary when manufacturing activated carbon. Furthermore, while it is generally necessary to knead activated carbon and a binder and mold it into a predetermined electrode shape to manufacture an activated carbon electrode, the method for manufacturing a second activated carbon electrode according to this embodiment allows for the production of tangible activated carbon, and a high-performance activated carbon electrode can be efficiently obtained without using a binder.

[0121] Furthermore, in the second method for manufacturing the activated carbon electrode of this embodiment, it is preferable that the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent. By including a hydrogen halide neutralizing agent in the halogen-based resin or the halogen-based resin molded article, rust on the manufacturing equipment due to the generation of hydrogen halides can be suppressed. In addition, by carbonizing the hydrogen halide neutralizing agent and the halogen-based resin together, the resulting activated carbon exhibits a carbon dioxide activation effect and forms sharper pores. In the halogen-based resin or the halogen-based resin molded article, the content of the hydrogen halide neutralizing agent is preferably 0.1% by mass or more, more preferably 0.1 to 91.0% by mass, even more preferably 50.0 to 91.0% by mass, and particularly preferably 65.0 to 91.0% by mass.

[0122] In this embodiment, the neutralizing agent for hydrogen halides is not particularly limited, but examples include calcium carbonate, magnesium carbonate, potassium carbonate, magnesium hydroxide, calcium hydroxide, sodium hydroxide, potassium hydroxide, iron(II) hydroxide, iron(III) hydroxide, zinc oxide, and calcium oxide. Among these, calcium carbonate, sodium hydroxide, potassium hydroxide, zinc oxide, and calcium hydroxide are preferred, calcium carbonate and zinc oxide are more preferred, and calcium carbonate is particularly preferred. Furthermore, when calcium carbonate is used as the neutralizing agent for hydrogen halides, for example, the calcium component is adsorbed onto the ultramicropores (0.6 nm or less) in the activated carbon electrode, reducing the ultramicropores, and tending to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors. The mechanism by which such an effect is exhibited is not clear, but the inventors of the present invention deduce the following: First, calcium carbonate reacts with the generated hydrogen halides to neutralize them. The amount of calcium carbonate required for neutralization is preferably about 1 kg per 1 kg of polyvinylidene chloride resin. However, to enhance the carbonation effect, it is preferable to use at least twice the amount of calcium carbonate relative to the polyvinylidene chloride resin. When calcium carbonate is heated, an endothermic reaction occurs at around 600-800°C, decomposing it into calcium oxide and carbon dioxide. Furthermore, the dechlorination reaction of vinylidene chloride is completed by 600°C (under a nitrogen atmosphere). Therefore, vinylidene chloride + calcium carbonate → vinylidene chloride carbon + calcium chloride + CO2 ２ +H ２ The reaction of O proceeds completely. During this process, the vinylidene chloride carbon is converted to CO ２ As a result, the specific surface area tends to increase due to the activation treatment. Furthermore, in this embodiment, it is preferable to wash off the calcium chloride with water and then dry to obtain activated carbon. In particular, in the obtained activated carbon, CO ２ Gas adsorption capacity: 64 cm ３A concentration of 1 / g or higher is preferable for this effect to manifest. Calcium ions form a hydrated structure, with an ion size of approximately 3 Å. The molecular size of water molecules is also approximately 3 Å, and the adsorption of calcium components onto activated carbon improves the pore size ratio to approximately 20 Å. The resulting activated carbon has a random carbon structure with small crystallite sizes. Such activated carbon tends to have a large D-band full width at half maximum and a large D / G ratio. As a result, the resulting activated carbon electrodes tend to exhibit high capacitance when applied to, for example, non-aqueous EDLCs and lithium-ion capacitors.

[0123] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is preferably a polyvinylidene chloride resin, a vinyl chloride resin, a chlorinated polyethylene resin, a polyvinylidene fluoride resin, a polyvinylidene fluoride resin, or a fluorinated polyethylene resin; more preferably a polyvinylidene chloride resin, a vinyl chloride resin, a polyvinylidene fluoride resin, or a polyvinylidene fluoride resin; even more preferably a polyvinylidene chloride resin or a polyvinylidene fluoride resin; and particularly preferably a polyvinylidene chloride resin. In this embodiment, for example, when a polyvinylidene chloride resin is used, the effects of the present invention tend to be further exhibited by utilizing the fact that a cross-linked structure of polyene (meaning a molecular skeleton structure having -C=C- or -C≡C-) is generated when the polyvinylidene chloride resin is dehydrochlorinated with a basic reagent, followed by a heat carbonization treatment. Furthermore, polyvinylidene chloride resins undergo dehydrochlorination easily, allowing for carbonization while relatively maintaining their molded form. By producing tangible activated carbon, the need for capacitor binders is eliminated, and activated carbon electrodes can be obtained more efficiently.

[0124] In this embodiment, the halogen-based resin or the halogen-based resin in the halogen-based resin molded article may be virgin raw material, recycled raw material, or bio-raw material, or any combination thereof. Here, "virgin raw material" refers to primary production raw material that is unused and has no recycling history. "Recycled raw material" refers to raw material obtained by recycling used or recovered materials from the manufacturing process, and includes post-consumer materials (PCR) and post-industrial materials (PIR). Recycled raw material may be obtained by mechanical recycling or chemical recycling. "Bio-raw material" refers to raw material derived from biomass. The ratio of bio-derived materials is not particularly limited.

[0125] The polyvinylidene chloride resin used in the method for producing the second activated carbon electrode of this embodiment is not particularly limited as long as it contains vinylidene chloride. In addition to vinylidene chloride, it may contain one or more monomers copolymerized with vinylidene chloride, such as vinyl chloride, acrylic acid esters such as methyl acrylate and butyl acrylate; methacrylic acid esters such as methyl methacrylate and butyl methacrylate; acrylonitrile; vinyl acetate, etc.

[0126] The weight-average molecular weight (Mw) of the polyvinylidene chloride resin used in the second activated carbon electrode of this embodiment is preferably 80,000 to 200,000, more preferably 90,000 to 180,000, and even more preferably 100,000 to 170,000. When the weight-average molecular weight (Mw) of the polyvinylidene chloride resin is within the above range, it tends to maintain the shape of the carbonized precursor, whether in powder form or molded form, even when the polyvinylidene chloride resin is thermally decomposed and carbonized. A polyvinylidene chloride resin with a weight-average molecular weight within the above range can be obtained, for example, by controlling the charging ratio of vinylidene chloride monomer to vinyl chloride monomer, the amount of polymerization initiator, or the polymerization temperature. In this embodiment, the weight-average molecular weight (Mw) can be determined using a standard polystyrene calibration curve by gel permeation chromatography (GPC).

[0127] In this embodiment, when the polyvinylidene chloride resin is a copolymer obtained by copolymerizing one or more monomers copolymerizable with vinylidene chloride, the copolymerization ratio of polyvinylidene chloride (constituent units derived from vinylidene chloride) is preferably 70% by mass or more, more preferably 72 to 100% by mass, even more preferably 81 to 100% by mass, even more preferably 85 to 100% by mass, and particularly preferably 85 to 93% by mass, based on the total amount of the polyvinylidene chloride resin. When the copolymerization ratio of polyvinylidene chloride is within the above range, excessive crystallization of the polyvinylidene chloride resin can be suppressed, thereby preventing the pore diameter from becoming excessively large when carbonized, and there is a tendency to be able to control it to a suitable pore diameter.

[0128] In the manufacturing method of this embodiment, activated carbon can be obtained by carbonizing and / or activating a halogen-based resin, or by carbonizing and / or activating a halogen-based resin molded body. To obtain activated carbon from a halogen-based resin or halogen-based resin molded body, only carbonization treatment is required, or only activation treatment is required. Of course, the halogen-based resin or halogen-based resin molded body may be carbonized and then activated. Furthermore, the activated carbon obtained by carbonization and / or activation can be subjected to higher-order activation treatments such as secondary activation and tertiary activation as needed. There are no particular restrictions on the carbonization method and the activation method.

[0129] The carbonization method is not particularly limited, but examples include firing a halogen-based resin or a halogen-based resin molded article in an inert gas such as nitrogen gas, carbon dioxide, helium, argon, xenon, neon, carbon monoxide, or combustion exhaust gas. By heating the halogen-based resin or the halogen-based resin in the halogen-based resin molded article (for example, polyvinylidene chloride), dehydrochlorination proceeds to form a polyene structure, and then carbonization occurs. The halogen-based resin or halogen-based resin molded article becomes activated carbon with a high specific surface area simply by thermal decomposition treatment in an inert gas. The thermal decomposition treatment conditions are preferably such that the heat treatment temperature is 500°C or higher, more preferably 500 to 1000°C, even more preferably 600 to 1000°C, even more preferably 700 to 1000°C, particularly preferably 800 to 1000°C, and most preferably 900 to 1000°C.

[0130] Examples of activation methods include gas activation methods using activating gases such as water vapor, carbon dioxide, carbon monoxide, hydrogen halides, and oxygen; and activation methods using the hydrogen halide neutralizing agent mentioned above. The heat treatment conditions vary depending on the type of activation method, but the heat treatment temperature is preferably 850°C or higher, and more preferably 850 to 900°C.

[0131] In the second method for manufacturing an activated carbon electrode of this embodiment, it is preferable to knead the obtained activated carbon and, if necessary, a conductive material, and then mold it into a predetermined electrode shape without using a binder. In this case, if necessary, an organic solvent, water, or other solvent (dispersion medium) can be added to form a slurry or paste before molding.

[0132] The conductive material is not particularly limited, but examples include conductive carbon black, graphite, metal fibers, titanium oxide, and ruthenium oxide. Examples of solvents include water, N-methylpyrrolidone, dimethylformamide, toluene, xylene, methyl ethyl ketone, ethyl acetate, methyl acetate, dimethyl phthalate, ethanol, methanol, and butanol. Water-soluble polymers such as polyvinyl alcohol may be added to improve dispersibility.

[0133] Typical methods for producing polarizing electrodes among activated carbon electrodes include: (1) a method in which a solvent is added to a mixture containing activated carbon, conductive material, etc. to make a mixed slurry, which is then applied to a current collector, or a method in which a current collector plate is immersed in the mixed slurry and dried; and (2) a method in which a solvent is added to a mixture containing activated carbon, conductive material, etc., and kneaded, the resulting paste-like mixture is rolled using a roller to form a sheet, and then the dried sheet is bonded to the surface of a current collector plate via a conductive adhesive, etc., then pressed, and heat-treated and dried.

[0134] [Applications] The electric double-layer capacitor of this embodiment is equipped with the above-mentioned activated carbon electrode as a polarizing electrode. The lithium-ion capacitor of this embodiment is also equipped with the above-mentioned activated carbon electrode as a polarizing electrode.

[0135] The structure of an electric double-layer capacitor is not particularly limited, but for example, in the case of a single-cell electric double-layer capacitor, a separator is sandwiched between two polarizing electrodes, and this is further sandwiched between current-collecting plates (collectoring electrodes), and this structure is sealed in a case containing an electrolyte via packing.

[0136] The solvent for the electrolyte is not particularly limited, but non-aqueous solvents such as propylene carbonate, ethylene carbonate, diethyl carbonate, dimethoxyethane, butylene carbonate, sulfolane, methylsulfolane, dimethyl carbonate, and ethyl methyl carbonate can be used. As the electrolyte, for example, (C ２ H ５ ) ４ NBF ４ , (C ２ H ５ ) (CH ３ ) NBF ４ , (C ２ H ５ ) (CH ３ ) PBF ４ These are some examples. Aqueous electrolytes such as dilute sulfuric acid can also be used. In particular, (C ２ H ５ ) ４ NBF ４An organic electrolyte, such as a propylene carbonate solution, is preferred.

[0137] The current collector plates for the positive and negative electrodes are not particularly limited, but for example, aluminum, stainless steel, nickel, etc. can be used. The shape of the current collector plates is not particularly limited, but for example, they can be foil-shaped, sheet-shaped, plate-shaped, expanded metal-shaped, or metal foam. The separator is not particularly limited, but for example, it can be glass fiber mat, cellulose paper made of Manila hemp or kraft paper, hydrophilic porous PTFE film, or polypropylene nonwoven fabric. The case material is not particularly limited, but for example, it can be aluminum, stainless steel, iron and its alloys, or synthetic resin (e.g., PTFE). The polarizing electrodes can be laminated or wound via a separator depending on the shape of the electric double-layer capacitor, etc.

[0138] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. The elements, arrangement, materials, conditions, shapes, and sizes of the embodiments are not limited to those exemplified and can be modified as appropriate. Furthermore, it is possible to partially substitute or combine the configurations shown in different embodiments.

[0139] The features of the present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited in any way by these. That is, the materials, amounts used, proportions, processing content, processing procedures, etc., shown in the following examples can be changed as appropriate, as long as they do not depart from the spirit of the present invention. Furthermore, the various manufacturing conditions and evaluation result values ​​in the following examples have meaning as preferred upper or lower limits in embodiments of the present invention, and the preferred range may be defined by a combination of the aforementioned upper or lower limits and the values ​​of the following examples or the values ​​of the examples themselves.

[0140] The measurement and evaluation methods in the examples and comparative examples are as follows.

[0141] (1) Area ratio of Raman D / G bands of activated carbon The area ratio of Raman D / G bands of activated carbon was measured as follows. First, the sample was placed on a slide glass with double-sided tape attached, and Raman measurement was performed under the following conditions. (Raman measurement conditions) Apparatus: Renishaw in Via Reflex Excitation wavelength: 532 nm Excitation light intensity: 1% Objective lens: 50x Measurement method: Confocal mode Diffraction grating: 1800 gr / mm Exposure time: 30 sec Integration: 8 scans Next, in the obtained Raman spectrum, the G band (1560-1600 cm⁻¹) was measured. －１ ), D band (1310-1350 cm) －１ For each of the above, peak fitting was performed using the Voigt model for the peaks and a linear model for the baseline, and the respective areas were calculated. From the obtained areas, the Raman D / G band area ratio of the activated carbon was calculated based on the following formula: D / G band area ratio = Area of ​​D band / Area of ​​G band

[0142] (2) Full width at half maximum of the Raman D band and G band of activated carbon The full width at half maximum of the Raman D band and G band of activated carbon were measured as follows. First, the sample was placed on a slide glass with double-sided tape attached, and Raman measurement was performed under the following conditions. (Raman measurement conditions) Apparatus: Renishaw in Via Reflex Excitation wavelength: 532 nm Excitation light intensity: 1% Objective lens: 50x Measurement method: Confocal mode Diffraction grating: 1800 gr / mm Exposure time: 30 sec Integration: 8 scans Next, in the obtained Raman spectrum, the G band (1560-1600 cm) was measured. －１ ), D band (1310-1350 cm) －１ For each of the above, peak fitting was performed using the Voigt model for the peaks and the linear model for the baseline, and the half-width at half maximum of the Raman D band and the half-width at half maximum of the G band of the activated carbon were calculated.

[0143] (3) Peak intensity ratio of Raman D / G bands of activated carbon The peak intensity ratio of Raman D / G bands of activated carbon was measured as follows. First, the sample was placed on a slide glass with double-sided tape attached, and Raman measurement was performed under the following conditions. (Raman measurement conditions) Apparatus: Renishaw in Via Reflex Excitation wavelength: 532 nm Excitation light intensity: 1% Objective lens: 50x Measurement method: Confocal mode Diffraction grating: 1800 gr / mm Exposure time: 30 sec Integration: 8 scans Next, in the obtained Raman spectrum, the G band (1560-1600 cm⁻¹) was measured. －１ ), D band (1310-1350 cm) －１ For each of the above, the maximum peak intensity was calculated. From the obtained maximum peak intensities, the Raman D / G band peak intensity ratio of the activated carbon was calculated based on the following formula: D / G peak intensity ratio = Maximum peak intensity of the D band / Maximum peak intensity of the G band

[0144] (4) Absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution The absolute value (nm) of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution (integral curve of differential pore volume distribution) was measured as follows. First, the gas adsorption test was performed using N ２The measurement was carried out under the condition of 77 K using gas. In this process, the pretreatment was performed by vacuum heating at 250° C. for 18 hours. Next, in the adsorption process, the pore volume at each pore diameter was evaluated based on the BJH method. As shown in FIG. 1, in the obtained pore size distribution, the cumulative pore volume distribution was calculated by summing the pore volumes from the measurement end point (A) to each measurement point (B). In this cumulative pore volume distribution, the cumulative pore volume distribution obtained by summing the pore volumes from the measurement end point (A) to the measurement start point (C) was defined as 100%. Further, the proportion of the cumulative pore volume distribution at each measurement point was calculated by the following formula. [{Cumulative pore volume distribution up to each measurement point (B) (cm ３ / g)} / {Cumulative pore volume distribution up to measurement start point (C) (cm ３ / g)}] × 100 (%) As shown in FIG. 1, regarding the proportion of the cumulative pore volume distribution at each measurement point, the pore diameter providing 25% of the volume was calculated by interpolation from the point (D) closest to 25%. That is, the pore diameter providing 25% of the volume was calculated by the following formula. [{Pore diameter of point (D) (nm)} / {Proportion of cumulative pore volume distribution up to point (D) (%)}] × 25 (%) Similarly, the pore diameter providing 75% of the volume was calculated by the following formula. That is, as shown in FIG. 1, regarding the proportion of the cumulative pore volume distribution at each measurement point, the pore diameter providing 75% of the volume was calculated by interpolation from the point (E) closest to 75%. [{Pore diameter of point (E) (nm)} / {Proportion of cumulative pore volume distribution up to point (E) (%)}] × 75 (%) In the cumulative pore volume distribution thus obtained, the absolute value of the difference between the pore diameters that provide 25% and 75% of the volume was calculated.

[0145] (5) Specific surface area of activated carbon The specific surface area of activated carbon (m ２ / g) was measured as follows. First, a gas adsorption test was carried out with N ２ gas under the condition of 77 K. In this process, the pretreatment was performed by vacuum heating at 250° C. for 18 hours. Next, the specific surface area of each sample was calculated based on the BET method.

[0146] (6) Average pore diameter of activated carbon The average pore diameter (nm) of activated carbon was measured as follows. First, a gas adsorption test was carried out with N ２The measurement was carried out under the condition of 77 K using gas. In this process, the pretreatment was carried out by vacuum heating at 250°C for 18 hours. Next, in the adsorption process, the total pore volume was evaluated based on the BJH method. Additionally, the total pore volume was calculated from the one-point method total pore volume obtained by setting the pore diameter to 98 nm. Furthermore, the average pore diameter (nm) of the activated carbon was calculated by the following formula. 4 × total pore volume (cm ３ / g) / specific surface area (m ２ / g) × 1000 (nm)

[0147] (7) CO ２ gas adsorption performance of activated carbon The CO ２ gas adsorption performance (cm ３ / g) of activated carbon was measured as follows. First, a gas adsorption test was conducted using CO ２ gas to obtain an adsorption isotherm under the condition of 25°C, and the adsorption amount at an absolute pressure of 760 mmHg was adopted. In this process, the pretreatment was carried out by vacuum heating at 250°C for 18 hours. The obtained CO ２ gas adsorption amount (cm ３ / g) was taken as the CO ２ gas adsorption performance.

[0148] (8) Capacitance density The capacitance density of an electric double layer capacitor was measured as follows. (8-1) Preparation of the first activated carbon electrode (1) Drying of activated carbon After drying activated carbon in a vacuum dryer at 150°C for 1 minute, it was placed in a sample bottle, sealed by wrapping with sealing tape, placed in a desiccator containing silica gel, and cooled to room temperature (this process took about 15 minutes). (2) Kneading of activated carbon 10% by mass of conductive acetylene black was ground in a mortar. 80% by mass of the dried activated carbon was quickly weighed, placed in a mortar, and thoroughly kneaded with the conductive acetylene black. Next, 10% by mass of polytetrafluoroethylene (PTFE) powder was added into the mortar and thoroughly stirred, then kneaded with a pestle to gather the whole mixture into a gum-like state. This gum-like substance was wrapped in powder paper and left in the atmosphere for 1 hour to prepare an electrode sample. (3) Fabrication of the electrode The above gum-like electrode sample was chopped with a razor blade, placed in a circular mold, and pressed at 500 MPa / cm ２The first activated carbon electrode was fabricated by press molding under pressure for 5 minutes. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. (8-2) Preparation of binderless activated carbon electrode (second activated carbon electrode) 10% by mass of conductive acetylene black was ground in a mortar. 90% by mass of halogen-based resin powder and neutralizing agent were quickly weighed and placed in the mortar, and thoroughly mixed with conductive acetylene black. Next, these samples were placed in a circular mold and subjected to pressure of 500 MPa / cm². ２ An activated carbon precursor was prepared by compression molding at 150°C for 5 minutes under pressure. The activated carbon precursor thus obtained was carbonized in a heating furnace at a predetermined temperature for 1 hour under a nitrogen atmosphere to prepare a binderless activated carbon electrode (second activated carbon electrode). The thickness of the electrode was measured with a thickness gauge and the volume was calculated. (8-3) Fabrication of an electric double-layer capacitor A conductive paste consisting of a mixture of conductive carbon black, hydroxymethylcellulose, and water was applied to each of two current collector plates made of SUS-316, and the electrodes were attached while they were semi-dry. A glass fiber filter (ADVANTEC: GA-200) was used as a separator, sandwiched between the two electrodes, and assembled into a PTFE cell. After that, it was dried in a vacuum dryer at 150°C for 3 hours and cooled in a glove box with a dew point of -90°C or lower. Next, the electrolyte was added and the cell was assembled. As the electrolyte, (C ２ H ５ ) ４ NBF ４ / A propylene carbonate (1 mol / L) solution was used. (8-4) Charge / Discharge Test The test was performed using a charge / discharge test machine (TOSCAT-3100U) from Toyo Systems Co., Ltd. Charging was first performed with a constant current of 5 mA until the voltage reached 2.3 V, then switched to low-voltage charging at 2.3 V, and the total charging time was set to 2.5 hours. Next, discharge was performed with a constant current of 5 mA, and the voltage was set to around 1 V. １ Time T to reach (bolt) １ (seconds), voltage V around 0.5V ０．５ Time T to reach (bolt) ０．５ We calculate (seconds). These relationships are shown in Figure 2. The capacitance (F) of the electric double-layer capacitor was calculated using the following formula: Capacitance (F) = I × (T０．５ -T １ ) / (V １ -V ０．５ Here, I is the discharge current in amperes. The capacitance of the electric double-layer capacitor obtained in this way is divided by the mass of activated carbon in the electrodes (total of positive and negative electrodes) and the volume of the electrodes (total of positive and negative electrodes) to obtain the capacitance per unit mass (F / g) and the capacitance per unit volume (F / cm²), respectively. ３ ) was defined as the volume per unit volume (F / cm³). ３ The capacitance per unit electrode volume (F / g) is the capacitance per unit mass of activated carbon that contributes to the capacitance. ３ The ranking criteria were as follows: 1: 180 F / cm ３ Below ~150F / cm ３ More than 2:150F / cm ３ Less than 135 F / cm ３ More than 3:135F / cm ３ Less than 120 F / cm ３ More than 4:120F / cm ３ Less than 105 F / cm ３ More than 5:105F / cm ３ Less than 95 F / cm ３ More than 6:95F / cm ３ Less than 90 F / cm ３ 7:90F / cm ３ Less than 85 F / cm ３ More than 8:85F / cm ３ Less than 80 F / cm ３ 9:80F / cm ３ Less than 76 F / cm ３ More than 10:76F / cm ３ Less than 73 F / cm ３ 11:73F / cm ３ Less than 70 F / cm ３ 12:70F / cm ３ Less than 67 F / cm ３ 13:67F / cm ３ Less than 64 F / cm ３ 14:64F / cm ３ Less than 62 F / cm３ 15:62F / cm ３ Less than 60 F / cm ３ More than 16:60F / cm ３ Less than 58 F / cm ３ 17:58F / cm ３ Less than 30 F / cm ３ or more 18:30F / cm ３ less than

[0149] (9) Residual Chlorine Concentration of Activated Carbon The residual chlorine concentration of activated carbon was measured by X-ray fluorescence as follows. Approximately 10 g of activated carbon was measured using a total X-ray fluorescence analyzer system 3270 manufactured by Rigaku Denki Co., Ltd. Note that the measuring device is not limited to the above description and can be measured using general equipment. The criteria for the XRF analysis rank of the residual chlorine concentration (mass%) of activated carbon were as follows: 1: Less than 0.0020 mass% to 0.0010 mass% or more 2: Less than 0.0025 mass% to 0.0020 mass% or more 3: Less than 0.0055 mass% to 0.0025 mass% or more 4: Less than 0.0200 mass% to 0.0055 mass% or more 5: Less than 5.0000 mass% to 0.0200 mass% or more 6: 5.0000 mass% or more

[0150] (10) Resistance to rusting during capacitor processing The resistance to rusting during capacitor processing was evaluated by creating a capacitor using the activated carbon described above, conducting charge and discharge tests, and then comparing the rusting state of the surfaces of two SUS-316 current collector plates with that of a standard plate (rusting degree 0 to 6). Each rusting degree represents the following state: 1: No rust. 2: Very slight rust occurs. 3: Very slight rust occurs. 4: Very minor rust occurs. 5: Minor rust occurs. 6: Very minor rust occurs.

[0151] (11) Resistance to rusting in the carbonization process The resistance to rusting in the carbonization process was evaluated by comparing the rusting state on the inner surface of the heating furnace with that of a standard plate (rusting degree 0 to 7) after firing the halogen-based resin or halogen-based resin molded body. Each rusting degree represents the following state: 1: No rust. 2: Very slight rust occurs. 3: Very slight rust occurs. 4: Very slight rust occurs. 5: Slight rust occurs. 6: Very slight rust occurs. 7: Slight rust occurs.

[0152] (12) Efficiency during capacitor fabrication The efficiency during capacitor fabrication was determined by the number of manufacturing steps involved. When using general activated carbon, four main steps are required: (i) drying of activated carbon, (ii) mixing of activated carbon with binder, (iii) creation of electrodes, and (iv) creation of electric double-layer capacitor. On the other hand, with binderless activated carbon electrodes, a capacitor can be created in only two steps: (I) creation of binderless activated carbon electrodes and (II) creation of electric double-layer capacitor. For this reason, binderless activated carbon electrodes are superior in efficiency during capacitor fabrication. Accordingly, the efficiency during capacitor fabrication was evaluated as follows: 1: Capacitor fabricated in 2 steps. 2: Capacitor fabricated in 4 steps.

[0153] [First Activated Carbon Electrode] [Example 1] Activated carbon was produced as follows, and various physical properties and evaluations of the obtained activated carbon were carried out by the above method. A total of 4000 g of raw materials, consisting of a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of vinylidene chloride-derived constituent units (PVDC) and 11% by mass of vinyl chloride-derived constituent units (PVC)) and calcium carbonate (Kanto Chemical Co., Ltd.), were mixed in proportions of 99.9% by mass and 0.1% by mass, respectively, and mixed in a Henschel mixer for 5 minutes and aged for 24 hours or more to obtain a polyvinylidene chloride resin composition. The activated carbon precursor thus obtained was carbonized in a heating furnace at 900°C for 1 hour under a nitrogen atmosphere. Thereafter, steam at 850°C was introduced and activated for 60 minutes to produce activated carbon. The obtained activated carbon was dried in a vacuum dryer at 150°C for 1 minute, then placed in a sample bottle, sealed with sealing tape, and cooled to room temperature in a silica gel desiccator (for approximately 15 minutes). 100 g of conductive acetylene black was ground in a mortar. 800 g of the dried activated carbon was quickly weighed and placed in the mortar, and thoroughly mixed with the conductive acetylene black. Next, 100 g of polytetrafluoroethylene (PTFE) powder was placed in the mortar and stirred well, then kneaded with a pestle until the mixture formed a gum-like substance. This gum-like substance was wrapped in weighing paper and left in the air for 1 hour to prepare the electrode sample. The above gum-like electrode sample was cut with a razor blade, placed in a circular mold, and subjected to 500 MPa / cm². ２Electrodes were fabricated by pressure molding for 5 minutes under the specified pressure. The thickness of the electrodes was measured with a thickness gauge, and the volume was calculated. The evaluation results of the obtained activated carbon electrodes are shown in Table 1.

[0154] [Example 2] An activated carbon electrode was prepared in the same manner as in Example 1, except that the carbonization temperature was set to 800°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0155] [Example 3] An activated carbon electrode was prepared in the same manner as in Example 1, except that the carbonization temperature was set to 700°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0156] [Example 4] An activated carbon electrode was prepared in the same manner as in Example 1, except that the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0157] [Example 5] An activated carbon electrode was prepared in the same manner as in Example 1, except that the carbonization temperature was set to 500°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0158] [Example 6] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0159] [Example 7] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in proportions of 9.0% by mass and 91.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 1.

[0160] [Example 8] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0161] [Example 9] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (70% by mass of constituent units derived from vinylidene chloride and 30% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0162] [Example 10] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the proportions of 99.9% by mass and 0.1% by mass, respectively, and the carbonization temperature was set to 600°C and the activation temperature to 900°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0163] [Example 11] An activated carbon electrode was prepared in the same manner as in Example 1, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 99.9% by mass and 0.1% by mass, respectively, and the carbonization temperature was set to 600°C and the activation temperature to 900°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0164] [Example 12] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 20.0% by mass and 80.0% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0165] [Example 13] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 25.0% by mass and 75.0% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0166] [Example 14] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 33.3% by mass and 66.7% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 2.

[0167] [Example 15] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0168] [Example 16] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 19.9% ​​by mass, 80.0% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0169] [Example 17] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 24.9% by mass, 75.0% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0170] [Example 18] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 33.2% by mass, 66.7% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0171] [Example 19] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0172] [Example 20] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), sodium hydroxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0173] [Example 21] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), potassium hydroxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively. The carbonization temperature was set to 950°C, and an activated carbon electrode was prepared in the same manner as in Example 1, except that no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 3.

[0174] [Comparative Example 1] An activated carbon electrode was prepared in the same manner as in Example 4, except that steam-activated activated carbon made from coconut shells was used and calcium carbonate was not used. The evaluation results of the obtained activated carbon electrode are shown in Table 4.

[0175] [Comparative Example 2] An activated carbon electrode was prepared in the same manner as in Example 4, except that polyethylene terephthalate resin (PET) was used as the raw material and calcium carbonate was not used. The evaluation results of the obtained activated carbon electrode are shown in Table 4.

[0176] [Comparative Example 3] An activated carbon electrode was prepared in the same manner as in Example 1, except that 100.0% by mass of polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (85% by mass of constituent units derived from vinylidene chloride and 15% by mass of constituent units derived from vinyl chloride) was used, the carbonization temperature was set to 700°C, and no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 4.

[0177] [Comparative Example 4] An activated carbon electrode was prepared in the same manner as in Example 1, except that 100.0% by mass of polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) was used in that order, the carbonization temperature was set to 700°C, and then an activation treatment was carried out at 700°C using zinc chloride. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 4.

[0178]

[0179]

[0180]

[0181]

[0182] [Second Activated Carbon Electrode] [Example 1-2] An activated carbon electrode was manufactured as follows, and various physical properties and evaluations of the obtained activated carbon electrode were carried out using the method described above. The results are shown in Table 1-2. A total of 900 g of raw materials, consisting of a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of vinylidene chloride-derived constituent units (PVDC) and 11% by mass of vinyl chloride-derived constituent units (PVC)) and calcium carbonate (Kanto Chemical Co., Ltd.), were mixed in the proportions of 99.9% by mass and 0.1% by mass, respectively, and mixed in a Henschel mixer for 5 minutes and aged for 24 hours or more to obtain a polyvinylidene chloride resin composition. 100 g of conductive acetylene black was ground in a mortar. The above polyvinylidene chloride resin composition was quickly placed in a mortar and kneaded well with the conductive acetylene black. Next, these samples were placed in a circular mold and subjected to 500 MPa / cm². ２ An activated carbon precursor was prepared by compression molding at 150°C for 5 minutes under pressure. The resulting activated carbon precursor was carbonized in a heating furnace at 900°C for 1 hour under a nitrogen atmosphere. Subsequently, steam at 850°C was introduced and activated for 60 minutes to produce a binderless activated carbon electrode. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0183] [Example 2-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that the carbonization temperature was set to 800°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0184] [Example 3-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that the carbonization temperature was set to 700°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0185] [Example 4-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0186] [Example 5-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that the carbonization temperature was set to 500°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0187] [Example 6-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0188] [Example 7-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in proportions of 9.0% by mass and 91.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 1-2.

[0189] [Example 8-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0190] [Example 9-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (70% by mass of constituent units derived from vinylidene chloride and 30% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0191] [Example 10-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in proportions of 99.9% by mass and 0.1% by mass, respectively, and the carbonization temperature was set to 600°C and the activation temperature to 900°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0192] [Example 11-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in proportions of 99.9% by mass and 0.1% by mass, respectively, and the carbonization temperature was set to 600°C and the activation temperature to 900°C. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0193] [Example 12-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 20.0% by mass and 80.0% by mass, respectively, and the carbonization temperature was set to 950°C, without performing an activation treatment. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0194] [Example 13-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 25.0% by mass and 75.0% by mass, respectively, and the carbonization temperature was set to 950°C, without performing an activation treatment. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0195] [Example 14-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in proportions of 33.3% by mass and 66.7% by mass, respectively, and the carbonization temperature was set to 950°C, and no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 2-2.

[0196] [Example 15-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride) and calcium hydroxide (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 950°C, and no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0197] [Example 16-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 19.9% ​​by mass, 80.0% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, with no activation treatment performed. The electrode thickness was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0198] [Example 17-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 24.9% by mass, 75.0% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, with no activation treatment performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0199] [Example 18-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 33.2% by mass, 66.7% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, with no activation treatment performed. The electrode thickness was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0200] [Example 19-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), zinc oxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, with no activation treatment performed. The electrode thickness was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0201] [Example 20-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), sodium hydroxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, and no activation treatment was performed. The electrode thickness was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0202] [Example 21-2] A binderless activated carbon electrode was prepared in the same manner as in Example 1-2, except that a polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (89% by mass of constituent units derived from vinylidene chloride and 11% by mass of constituent units derived from vinyl chloride), potassium hydroxide (Kanto Chemical Co., Ltd.), and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in the following proportions: 49.9% by mass, 50.0% by mass, and 0.10% by mass, respectively, and the carbonization temperature was set to 950°C, with no activation treatment performed. The electrode thickness was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained binderless activated carbon electrode are shown in Table 3-2.

[0203] [Comparative Example 1-2] A polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride, 0% by mass of constituent units derived from vinyl chloride) and calcium carbonate (Kanto Chemical Co., Ltd.) were mixed in a ratio of 50.0% by mass and 50.0% by mass, respectively, and the carbonization temperature was set to 600°C. An activated carbon electrode was prepared in the same manner as in Example 1-2, except that a binder was used to prepare the electrode for the capacitor. The preparation of the activated carbon electrode using a binder was carried out in the following procedure: (1) Dry activated carbon The dried activated carbon was dried in a vacuum dryer at 150°C for 1 minute, then placed in a sample bottle, sealed with sealing tape, and cooled to room temperature in a silica gel desiccator (for about 15 minutes). (2) Kneading activated carbon 100 g of conductive acetylene black was ground in a mortar. 800 g of dried activated carbon was quickly weighed out and placed in a mortar and kneaded well with conductive acetylene black. Next, 100 g of polytetrafluoroethylene (PTFE) powder was placed in a mortar and stirred well, then kneaded with a pestle until the mixture formed a gum-like substance. This gum-like substance was wrapped in weighing paper and left in the air for 1 hour to prepare the electrode sample. (3) Electrode preparation The above gum-like electrode sample was cut with a razor blade and placed in a circular mold, and subjected to 500 MPa / cm ２ Electrodes were fabricated by pressure molding for 5 minutes under the specified pressure. The thickness of the electrodes was measured with a thickness gauge, and the volume was calculated. The evaluation results of the obtained activated carbon electrodes are shown in Table 4-2.

[0204] [Comparative Example 2-2] An activated carbon electrode was prepared in the same manner as in Comparative Example 1-2, except that steam-activated activated carbon made from coconut shells was used. The evaluation results of the obtained activated carbon electrode are shown in Table 4-2.

[0205] [Comparative Example 3-2] An activated carbon electrode was prepared in the same manner as in Comparative Example 1-2, except that polyethylene terephthalate resin (PET) was used as the raw material. The evaluation results of the obtained activated carbon electrode are shown in Table 4-2.

[0206] [Comparative Example 4-2] An activated carbon electrode was prepared in the same manner as in Comparative Example 1-2, except that 100.0% by mass of polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (85% by mass of constituent units derived from vinylidene chloride and 15% by mass of constituent units derived from vinyl chloride) was used, the carbonization temperature was set to 700°C, and no activation treatment was performed. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 4-2.

[0207] [Comparative Example 5-2] An activated carbon electrode was prepared in the same manner as in Comparative Example 1-2, except that 100.0% by mass of polyvinylidene chloride resin with a weight-average molecular weight of 120,000 (100% by mass of constituent units derived from vinylidene chloride and 0% by mass of constituent units derived from vinyl chloride) was used in that order, the carbonization temperature was set to 700°C, and then an activation treatment was carried out at 700°C using zinc chloride. The thickness of the electrode was measured with a thickness gauge and the volume was calculated. The evaluation results of the obtained activated carbon electrode are shown in Table 4-2.

[0208]

[0209]

[0210]

[0211]

[0212] This application is based on Japanese Patent Application No. 2025-048855 and Japanese Patent Application No. 2025-048908, both filed on March 24, 2025, the contents of which are incorporated herein by reference.

Claims

1. Activated carbon in which, in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method, the absolute value of the difference in pore diameters that give volumes 25% and 75% is 5.00 to 0.60 nm, and the average pore diameter is 5.0 to 1.5 nm.

2. CO ２ Gas adsorption capacity is 64 cm ３ The activated carbon according to claim 1, wherein the amount is 1g or more.

3. The activated carbon according to claim 1 or 2, wherein the half-width of the Raman D band is 150 or more.

4. The activated carbon according to claim 1 or 2, wherein the area ratio of the Raman D / G bands is 2.7 or more.

5. The activated carbon according to claim 1 or 2, wherein the half-width of the Raman G band is 64.0 to 41.

5.

6. The activated carbon according to claim 1 or 2, wherein the peak intensity ratio of the Raman D / G bands is 0.99 or less.

7. Specific surface area of ​​1150 to 3550 m² ２ The activated carbon according to claim 1 or 2, wherein the amount is / g.

8. The activated carbon according to claim 1 or 2, wherein the residual chlorine concentration calculated by X-ray fluorescence is 5.0% by mass or less.

9. The activated carbon according to claim 1 or 2, comprising a carbonizing and / or activating substance for halogenated resins, or a carbonizing and / or activating substance for a halogenated resin molded article.

10. The activated carbon according to claim 9, wherein the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent.

11. The activated carbon according to claim 9, wherein the halogen-based resin or the halogen-based resin in the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

12. An activated carbon electrode comprising the activated carbon described in claim 1 or 2 and a binder.

13. An electric double-layer capacitor comprising the activated carbon electrode described in claim 12 as a polarizing electrode.

14. A lithium-ion capacitor comprising the activated carbon electrode described in claim 12 as a polarizing electrode.

15. A method for producing activated carbon, comprising the steps of carbonizing and / or activating a halogen-based resin, or carbonizing and / or activating a halogen-based resin molded article.

16. The method for producing activated carbon according to claim 15, wherein the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent.

17. The method for producing activated carbon according to claim 15 or 16, wherein the halogen-based resin or the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

18. An activated carbon electrode containing activated carbon, without a binder, in which the absolute value of the difference in pore diameters that give volumes 25% and 75% in the cumulative pore volume distribution (integral curve of differential pore volume distribution) calculated by the BJH method is 5.00 to 0.60 nm.

19. CO2 from the activated carbon ２ Gas adsorption capacity is 64 cm ３ The activated carbon electrode according to claim 18, wherein the amount is 1g or more.

20. The activated carbon electrode according to claim 18 or 19, wherein the half width at half maximum of the Raman D band of the activated carbon is 150 or more.

21. The activated carbon electrode according to claim 18 or 19, wherein the area ratio of the Raman D / G bands of the activated carbon is 2.7 or more.

22. The activated carbon electrode according to claim 18 or 19, wherein the half width at half maximum of the Raman G band of the activated carbon is 64.0 to 41.

5.

23. The activated carbon electrode according to claim 18 or 19, wherein the peak intensity ratio of the Raman D / G band of the activated carbon is 0.99 or less.

24. The specific surface area of ​​the activated carbon is 1150 to 3550 m². ２ The activated carbon electrode according to claim 18 or 19, wherein the value is / g.

25. The activated carbon electrode according to claim 18 or 19, wherein the average pore size of the activated carbon, calculated by the BJH method, is 5.0 to 1.

5.

26. The activated carbon electrode according to claim 18 or 19, wherein the residual chlorine concentration of the activated carbon, calculated by X-ray fluorescence, is 5.0% by mass or less.

27. The activated carbon electrode according to claim 18 or 19, wherein the activated carbon comprises a carbonizing and / or activating substance for halogen-based resins, or a carbonizing and / or activating substance for a halogen-based resin molded article.

28. The activated carbon electrode according to claim 27, wherein the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent.

29. The activated carbon electrode according to claim 27, wherein the halogen-based resin or the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

30. An electric double-layer capacitor comprising the activated carbon electrode according to claim 18 or 19 as a polarizing electrode.

31. A lithium-ion capacitor comprising the activated carbon electrode according to claim 18 or 19 as a polarizing electrode.

32. A method for producing an activated carbon electrode, comprising the steps of: obtaining activated carbon by carbonizing and / or activating a halogen-based resin; or obtaining activated carbon by carbonizing and / or activating a halogen-based resin molded body; and obtaining an activated carbon electrode by molding the obtained activated carbon without using a binder.

33. The method for producing an activated carbon electrode according to claim 32, wherein the halogen-based resin or the halogen-based resin molded article contains a hydrogen halide neutralizing agent.

34. The method for producing an activated carbon electrode according to claim 32 or 33, wherein the halogen-based resin or the halogen-based resin molded article is a polyvinylidene chloride resin, and the copolymerization ratio of polyvinylidene chloride in the polyvinylidene chloride resin is 70% by mass or more.

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