Disclosed is a carbon-based fiber sheet and a lithium-sulfur battery including the same. The carbon-based fiber sheet for the lithium-sulfur battery is doped with a high concentration of nitrogen and thus plays a role of preventing diffusion by adsorbing lithium polysulfide eluted from a positive electrode during charging and discharging, thereby suppressing a shuttle reaction and thus improving capacity and lifecycle properties of the lithium-sulfur battery.

Disclosed is a carbon-based fiber sheet and a lithium-sulfur battery including the same. The carbon-based fiber sheet for the lithium-sulfur battery is doped with a high concentration of nitrogen and thus plays a role of preventing diffusion by adsorbing lithium polysulfide eluted from a positive electrode during charging and discharging, thereby suppressing a shuttle reaction and thus improving capacity and lifecycle properties of the lithium-sulfur battery.

A method for joule carbonization of fibers includes subjecting the fibers, made from an intrinsically electrically-conductive material, to a current density sufficient to heat the fibers to a carbonization temperature of between 900-2000° C. whereby the fibers are carbonized into carbon fibers. A method for joule graphitization of fibers includes subjecting the fibers, made from an intrinsically electrically-conductive material, to a current density sufficient to heat the fibers to a graphitization temperature of between 2400-3000° C. whereby the fibers are graphitized into graphitic carbon fiber.

A method for joule carbonization of fibers includes subjecting the fibers, made from an intrinsically electrically-conductive material, to a current density sufficient to heat the fibers to a carbonization temperature of between 900-2000° C. whereby the fibers are carbonized into carbon fibers. A method for joule graphitization of fibers includes subjecting the fibers, made from an intrinsically electrically-conductive material, to a current density sufficient to heat the fibers to a graphitization temperature of between 2400-3000° C. whereby the fibers are graphitized into graphitic carbon fiber.

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.

Provided is a manufacturing method of a graphene-based liquid crystal fiber including: polymerizing a first aromatic monomer on a graphene-based compound to prepare a graphene composite in which a first aromatic polymer is surface-polymerized on the graphene-based compound; wet-spinning the graphene composite to manufacture a hydrogel fiber; and polymerizing a second aromatic monomer on the hydrogel fiber to fill pores of the hydrogel fiber with a second aromatic polymer.

Provided is a manufacturing method of a graphene-based liquid crystal fiber including: polymerizing a first aromatic monomer on a graphene-based compound to prepare a graphene composite in which a first aromatic polymer is surface-polymerized on the graphene-based compound; wet-spinning the graphene composite to manufacture a hydrogel fiber; and polymerizing a second aromatic monomer on the hydrogel fiber to fill pores of the hydrogel fiber with a second aromatic polymer.

A method of producing a fiber is provided, the method including extruding, from a spinneret, a spinning dope solution containing a fiber-forming polymer dissolved in a solvent, once allowing the solution to run in air, and then guiding the solution into the liquid of a coagulation bath to allow coagulation, wherein a gas-phase portion formed in a vertically downward direction from an extrusion surface of the spinneret to the liquid surface of the coagulation bath has a unidirectional air flow, and has an air flow rate per unit time (Af) which satisfies, in relation to the amount of the solvent in the spinning dope solution per unit time (As) in the gas-phase-portion volume (Vh), the relational expression 0.0008 m.sup.3≤Af/(As/Vh)≤0.0015 m.sup.3. A method of producing a fiber, which, in dry-jet wet spinning, suppresses occurrence of dew condensation in the spinneret, and reduces deterioration of the appearance caused by winding on rollers in the subsequent process or by fuzzing or yarn break in the stretching process, to enable significant improvement of the productivity and the appearance as a whole, is provided.

Lithium ion batteries, electrodes, nanofibers, and methods for producing same are disclosed herein. Provided herein are batteries having (a) increased energy density; (b) decreased pulverization (structural disruption due to volume expansion during lithiation/de-lithiation processes); and/or (c) increased lifetime. In some embodiments described herein, using high throughput, water-based electrospinning process produces nanofibers of high energy capacity materials (e.g., ceramic) with nanostructures such as discrete crystal domains, mesopores, hollow cores, and the like; and such nanofibers providing reduced pulverization and increased charging rates when they are used in anodic or cathodic materials.