Described herein is a method of in situ production of supported nanoparticles using centrifugal spinning to provide a composite fiber structure of polymer or carbon fibers having nanoparticles disposed on the surface. The nanoparticles may be salt particles or elemental metal particles.

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.3Af/(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.

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.

Pyrolysis (carbonization) of various plastics, including recycled plastic, can generate carbonaceous materials cheaply and in bulk, which can then be converted into energy storage device materials, e.g., carbon anode active material for Li-ion batteries. The plastic can be dissolved in a suitable solvent or acid, or can be melted. Once liquefied it can be loaded into vessels for extrusion via an electrospinner. Polymer fibers may be formed from the liquefied plastic on the nano- and micro scales, and collected on a substrate, forming a fabric. These fibers can be converted to high purity carbon and used as electrode materials in batteries and supercapacitors. The fibers can also be coated with Ppy prior to pyrolysis; this helps fibers retain their morphology during carbonization. The fibers can also be loaded with additive particles to enhance their electrochemical performance or alter the composite properties.

Pyrolysis (carbonization) of various plastics, including recycled plastic, can generate carbonaceous materials cheaply and in bulk, which can then be converted into energy storage device materials, e.g., carbon anode active material for Li-ion batteries. The plastic can be dissolved in a suitable solvent or acid, or can be melted. Once liquefied it can be loaded into vessels for extrusion via an electrospinner. Polymer fibers may be formed from the liquefied plastic on the nano- and micro scales, and collected on a substrate, forming a fabric. These fibers can be converted to high purity carbon and used as electrode materials in batteries and supercapacitors. The fibers can also be coated with Ppy prior to pyrolysis; this helps fibers retain their morphology during carbonization. The fibers can also be loaded with additive particles to enhance their electrochemical performance or alter the composite properties.

There is provided a method of making a hollow fiber having improved resistance to microfracture formation at a fiber-matrix interface. The method includes mixing in a first solvent a plurality of nanostructures, one or more first polymers, and a fugitive polymer which is dissociable from the nanostructures and the one or more first polymers, to form an inner-volume portion mixture. The method further includes mixing in a second solvent one or more second polymers to form an outer-volume portion mixture, spinning the inner-volume portion mixture and the outer-volume portion mixture and extracting the fugitive polymer from the inner-volume portion mixture to form a precursor fiber, heating the precursor fiber to oxidize the precursor fiber and to change a molecular-bond structure of the precursor fiber, and obtaining a hollow fiber with the inner-volume portion having the nanostructures and the first polymers, and with the outer-volume portion having the second polymers.

There is provided a method of making a fiber having improved resistance to microfracture formation at a fiber-matrix interface. The method includes mixing a plurality of nanostructures and one or more first polymers in a first solvent to form an inner-volume portion mixture, mixing one or more second polymers in a second solvent to form an outer-volume portion mixture, spinning the inner-volume portion mixture and the outer-volume portion mixture to form a precursor fiber, heating the precursor fiber to oxidize the precursor fiber and to change a molecular-bond structure of the precursor fiber, and obtaining a fiber. The fiber has an inner-volume portion with a first outer diameter, the nanostructures, and with the one or more first polymers, and has an outer-volume portion with a second outer diameter and the one or more second polymers, the outer-volume portion being in contact with and completely encompassing the inner-volume portion.

The present invention relates to a carbon-based fiber sheet and a lithium-sulfur battery including the same.

The carbon-based fiber sheet for the lithium-sulfur battery according to the present invention 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.

The present invention relates to a carbon-based fiber sheet and a lithium-sulfur battery including the same.

The carbon-based fiber sheet for the lithium-sulfur battery according to the present invention 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.

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.