Abstract: A carbon fiber bundle may have a total fineness of 2 g/m or more and a variation rate of a thickness of the fiber bundle of 30% or less in a width direction of the fiber bundle. A manufacturing method of a carbon fiber bundle may include applying a sizing agent to the carbonized fiber bundle, drying the carbonized fiber bundle, then passing the carbonized fiber bundle such that one surface of the carbonized fiber bundle in the width direction and one opposite surface thereof are alternately brought into contact with two or more parallel rods, and winding the carbonized fiber bundle on a bobbin.

Abstract: A hydrophilic porous carbon electrode which has excellent hydrophilicity, which has high reaction activity when used for a battery, and with which excellent battery characteristics is able to be obtained is provided. A hydrophilic porous carbon electrode is a sheet-form hydrophilic porous carbon electrode in which a carbon fiber is bonded using a resin carbide and has a contact angles ?A of water on both surfaces in a thickness direction being 0 to 15° and a contact angle ?B of water in a middle portion in the thickness direction being 0 to 15°. The hydrophilic porous carbon electrode is obtained by forming the carbon fiber and a binder fiber into a sheet, impregnating the sheet into a thermosetting resin, subjecting it to heat press processing, and then subjecting it to carbonization at 400 to 3000° C. in an inert atmosphere. The hydrophilic porous carbon electrode is transported and is subjected to a heat treatment while an oxidizing gas flows at 400 to 800° C.

Abstract: Provided is a porous electrode substrate capable of reducing a drop in electromotive force when used in a battery. This porous electrode substrate comprises a carbon fiber sheet wherein carbon fibers are bound by a binder. For dust of 0.3 ?m or more in particle size, the dust generation amount per 1 m2 of the porous electrode substrate is 120,000/m2 or less, as determined by the following method: dust particles in a gas obtained by suctioning at 47.2 mL/s for 40 minutes using a dust collecting hood having an opening of 500 mm×100 mm while traveling the sheet at a speed of 10 m/min from a position 200 mm below the sheet are used; the number of dust particles having a diameter within a predetermined range is measured by a particle counter; and the measured value is divided by 200 m2, which is a suction area, and the resulting value is defined as a dust generation amount per 1 m2.

Abstract: A hydrophilic porous carbon electrode which has excellent hydrophilicity, which has high reaction activity when used for a battery, and with which excellent battery characteristics is able to be obtained is provided. A hydrophilic porous carbon electrode is a sheet-form hydrophilic porous carbon electrode in which a carbon fiber is bonded using a resin carbide and has a contact angles ?A of water on both surfaces in a thickness direction being 0 to 15° and a contact angle ?B of water in a middle portion in the thickness direction being 0 to 15°. The hydrophilic porous carbon electrode is obtained by forming the carbon fiber and a binder fiber into a sheet, impregnating the sheet into a thermosetting resin, subjecting it to heat press processing, and then subjecting it to carbonization at 400 to 3000° C. in an inert atmosphere. The hydrophilic porous carbon electrode is transported and is subjected to a heat treatment while an oxidizing gas flows at 400 to 800° C.

Abstract: A hydrophilic porous carbon electrode which has excellent hydrophilicity, which has high reaction activity when used for a battery, and with which excellent battery characteristics is able to be obtained is provided. A hydrophilic porous carbon electrode is a sheet-form hydrophilic porous carbon electrode in which a carbon fiber is bonded using a resin carbide and has a contact angles ?A of water on both surfaces in a thickness direction being 0 to 15° and a contact angle ?B of water in a middle portion in the thickness direction being 0 to 15°. The hydrophilic porous carbon electrode is obtained by forming the carbon fiber and a binder fiber into a sheet, impregnating the sheet into a thermosetting resin, subjecting it to heat press processing, and then subjecting it to carbonization at 400 to 3000° C. in an inert atmosphere. The hydrophilic porous carbon electrode is transported and is subjected to a heat treatment while an oxidizing gas flows at 400 to 800° C.

Abstract: A hydrophilic porous carbon electrode which has excellent hydrophilicity, which has high reaction activity when used for a battery, and with which excellent battery characteristics is able to be obtained is provided. A hydrophilic porous carbon electrode is a sheet-form hydrophilic porous carbon electrode in which a carbon fiber is bonded using a resin carbide and has a contact angles ?A of water on both surfaces in a thickness direction being 0 to 15° and a contact angle ?B of water in a middle portion in the thickness direction being 0 to 15°. The hydrophilic porous carbon electrode is obtained by forming the carbon fiber and a binder fiber into a sheet, impregnating the sheet into a thermosetting resin, subjecting it to heat press processing, and then subjecting it to carbonization at 400 to 3000° C. in an inert atmosphere. The hydrophilic porous carbon electrode is transported and is subjected to a heat treatment while an oxidizing gas flows at 400 to 800° C.

Abstract: Provided is a porous electrode substrate capable of reducing a drop in electromotive force when used in a battery. This porous electrode substrate comprises a carbon fiber sheet wherein carbon fibers are bound by a binder. For dust of 0.3 ?m or more in particle size, the dust generation amount per 1 m2 of the porous electrode substrate is 120,000/m2 or less, as determined by the following method: dust particles in a gas obtained by suctioning at 47.2 mL/s for 40 minutes using a dust collecting hood having an opening of 500 mm×100 mm while traveling the sheet at a speed of 10 m/min from a position 200 mm below the sheet are used; the number of dust particles having a diameter within a predetermined range is measured by a particle counter; and the measured value is divided by 200 m2, which is a suction area, and the resulting value is defined as a dust generation amount per 1 m2.