A method for manufacturing a carbon fiber sheet, the method including a carbon fiber forming step of heating a resin sheet to a carbonization temperature at a heating rate of 15,000° C./sec or higher, thereby forming a carbon fiber from the resin sheet. In the carbon fiber forming step, the resin sheet is preferably irradiated with an energy ray having an output density of 130 W/mm.sup.2 or higher and an amount of irradiation energy of 0.05 J/mm.sup.2 or more.

A method of preparing a structure, more particularly, a method of preparing a structure capable of ensuring a space for carrying an electrode active material by a simple method which includes an electrospinning process using a double nozzle electrospinning device and a heat treatment process.

A method of preparing a structure, more particularly, a method of preparing a structure capable of ensuring a space for carrying an electrode active material by a simple method which includes an electrospinning process using a double nozzle electrospinning device and a heat treatment process.

A heating element is used, a periphery of the heating element is covered with a net-shaped conductor, the conductor and a carbon fiber bundle are electrically connected with a connecting tool at one end of the heating element, a periphery of the conductor is covered with an outer skin having flexibility, thermal conductivity and an insulating property, and the other end of the heating element is provided with a power supply terminal configured to supply power.

The present invention relates to a high heat-resistant graphene oxide, a method of manufacturing conductive graphene fiber from the same, and conductive graphene fiber manufactured by the method. The technical gist of the present invention is to provide high heat-resistant graphene oxide not having an oxygen-containing functional group such as a lactol group or a carboxyl group on the surface but having an oxygen-containing functional group such as an epoxy group or a hydroxyl group on the surface, thereby exhibiting thermal resistance and stability. In addition, the technical gist is also to provide a method of manufacturing conductive graphene fiber from the high heat-resistant graphene oxide and conductive graphene fiber manufactured by the method.

The present invention relates to a high heat-resistant graphene oxide, a method of manufacturing conductive graphene fiber from the same, and conductive graphene fiber manufactured by the method. The technical gist of the present invention is to provide high heat-resistant graphene oxide not having an oxygen-containing functional group such as a lactol group or a carboxyl group on the surface but having an oxygen-containing functional group such as an epoxy group or a hydroxyl group on the surface, thereby exhibiting thermal resistance and stability. In addition, the technical gist is also to provide a method of manufacturing conductive graphene fiber from the high heat-resistant graphene oxide and conductive graphene fiber manufactured by the method.

The invention relates to a method for the production of a conductive micro-wire from carbon nanotubes by means of carbonization, and the uses thereof in electro-chemical processes and devices, for example, as electrodes in electrical generators. The invention can be included in the field of manufacturing nanomaterials and carbon nanotubes, as well as electrodes for electro-chemical processes and electrical conductors.

A carbon fiber bundle includes single-fibers 40% or more of which have a quasi-oval cross section perpendicular to a fiber direction and meet both Equations (1) and (2): 1.03≤La/Lb≤1.20 (1) and 1.05≤Ld/Lc≤1.25 (2), wherein La is length of a long axis defined as a line segment connecting two points farthest away from each other on a circumference of the quasi-oval cross section of a single-fiber; Lb is length of a short axis defined as a line segment extending perpendicular to the long axis, passing through a midpoint of the long axis, and connecting two points on the circumference; and Lc and Ld are defined as length of a shorter one and that of a longer one, respectively.

A carbon fiber bundle includes single-fibers 40% or more of which have a quasi-oval cross section perpendicular to a fiber direction and meet both Equations (1) and (2): 1.03≤La/Lb≤1.20 (1) and 1.05≤Ld/Lc≤1.25 (2), wherein La is length of a long axis defined as a line segment connecting two points farthest away from each other on a circumference of the quasi-oval cross section of a single-fiber; Lb is length of a short axis defined as a line segment extending perpendicular to the long axis, passing through a midpoint of the long axis, and connecting two points on the circumference; and Lc and Ld are defined as length of a shorter one and that of a longer one, respectively.

A curing process includes providing a hybrid material comprising a conductive filler in contact with a thermosetting resin. In addition, the curing process includes passing an electric current through the hybrid material to provide Joule heating until a temperature of the hybrid material reaches a temperature above a curing temperature of the thermosetting resin.