Lg Chem, Ltd

Kyung Yeon Kang

Dong Hyun Cho

Sung Jin Kim

Jae Keun Yoon

Jihee Woo

Jin Do Kim

Sang Hoon Choy

Hyun Joon Kang

Seungyong Lee

Hyungsik Jang

Ki Soo Lee

Ye Lin Kim

SungJin Kim

Jong Heon Seol

Yelin Kim

Ji Hee Woo

Seung Yong Lee

Jung Keun Yoo

JaeKeun Yoon

Seok Won Kim

Jindo Kim

Soon Ki Jeong

The present invention relates to a method for preparing carbon nanotubes, the method including: preparing a support including AlO(OH) by primary heat treatment of Al(OH); preparing an active carrier by supporting a mixture including a main catalyst precursor and a cocatalyst precursor on the support; drying the active carrier through multi-stage drying including vacuum drying; preparing a supported catalyst by secondary heat treatment of the dried active support; and preparing carbon nanotubes in the presence of the supported catalyst, and the carbon nanotubes prepared by the method as described above can remarkably improve conductivity.

Method for preparing carbon nanotubes

The present invention relates to carbon nanotubes having a pore volume of 0.94 cm/g or more, and being an entangled type, a method of manufacturing the same, and a positive electrode for a primary battery which comprises the same.

Carbon nanotubes, method of manufacturing same, and positive electrode for primary battery comprising same

The present invention relates to a method for preparing a carbon nanotube dispersion, the method including mixing a dispersion solution including a dispersion solvent and a dispersant with carbon nanotubes to prepare carbon nanotube paste, extruding the paste to obtain solid carbon nanotubes, and introducing a second solvent to the solid carbon nanotubes, and homogenizing the carbon nanotubes, wherein the weight ratio of the dispersion solution and the carbon nanotubes is 1:1 to 9:1. According to the present invention, the mixing of a dispersant and carbon nanotubes is increased and the particle size is controlled by a wet method, so that a carbon nanotube dispersion having a viscosity controlled to a low level, excellent resistance properties, and a high concentration, may be provided.

Method for preparing carbon nanotube dispersion

In the present invention, by dry pulverizing carbon nanotubes to control wettability index of the carbon nanotubes, the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent can be increased and the workability of the carbon nanotube dispersion can be improved. Further, from this, it is possible to more easily predict the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent.

Method for producing carbon nanotube dispersion with improved workability

The apparatus for manufacturing carbon nanotube pellets according to the present invention provides carbon nanotube pellets with increased apparent density by using only a small amount of solvent. The carbon nanotube pellets produced by the apparatus according to the present invention can improve various problems generated by scattering of powders. And since the density of the pellet form is high, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.

Apparatus for manufacturing carbon nanotube pellets

The present invention provides: a conductive material dispersed liquid containing a conductive material, a dispersant, and a dispersion medium, wherein the conductive material comprises bundle-type carbon nanotubes having a bulk density in a range of 10-50 kg/mand a conductivity satisfying the conditions of Equation 1 below, thereby exhibiting excellent dispersibility and conductivity; and a lithium secondary battery, which is manufactured using the conductive material dispersed liquid and thus can exhibit excellent battery functions, especially, excellent output characteristics at low temperatures:&#x2212;&#x2264;10 log&#x2264;&#x2212;0.6&#x2003;&#x2003;[Equation 1]

Conductive material dispersed liquid and lithium secondary battery manufactured using the same

The carbon nanotubes according to the present invention can provide higher conductivity by allowing the BET and crystal size to satisfy the conditions expressed by formula 1 below, and consequently, can improve the conductivity of a carbon composite material containing the carbon nanotubes.&#xd7;[Specific surface area of CNT (cm/g)]&#x3e;80&#x2003;&#x2003;[Formula 1]

Highly conductive carbon nanotubes and method for manufacturing same

The present invention provides a conductive material for a secondary battery, and a secondary battery containing the same, the conductive material comprising carbon nanotubes, having a secondary structure in which carbon nanotube units having a diameter of 20-150 nm are entangled, having a ratio of true density to bulk density (TD/BD) of 30-120, having a metal content of 50 ppm or less, and having both excellent dispersibility and high purity, thereby being capable of improving, by increasing the conductivity within an electrode, battery performance, particularly, battery performance at room temperature and low temperature when applied to a battery.

Conductive material for secondary battery, and secondary battery containing same

The method for producing carbon nanotube pellets according to the present invention can reduce the particle size of the carbon nanotubes contained in the pellet by a repetitive extrusion process to produce pellets having improved dispersion characteristics in a solvent. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.

Carbon nanotube pellets and method for manufacturing same

The carbon nanotube pellets according to the present invention are produced by using only a small amount of solvent and have increased apparent density. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet rather than carbon nanotubes in the form of powder in composite materials. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.

Disclosed is a method for manufacturing a homogeneous supported catalyst for carbon nanotubes. Advantageously, the method induces deep impregnation of a catalyst in micro pores of a support by using high-temperature aging impregnation, thus providing a high CNT yield.

Method for manufacturing homogeneous supported catalyst for carbon nanotubes

Disclosed are carbon nanotubes and a method for manufacturing the same. Advantageously, the method provides a high yield of potato or sphere-shaped non-bundled carbon nanotubes having a bulk density of 80 to 250 kg/m, an ellipticity of 0.9 to 1.0 and a particle diameter distribution (Dcnt) of 0.5 to 1.0 using a two-component carbon nanotube catalyst comprising a catalyst component and an active component.

Carbon nanotubes and method for manufacturing the same

Disclosed are carbon nanotubes and a method for manufacturing the same wherein the carbon nanotubes (CNTs) which comprise a three-component carbon nanotube catalyst containing a catalytic component and an active component and have a potato or spherical shape with a particle diameter distribution (Dcnt) of 0.5 to 1.0 can be manufactured at a high yield using an impregnated supported catalyst by simultaneously removing activity and a fine powder of the impregnated supported catalyst in an attempt to solve a drawback of conventional impregnation methods for producing CNTs, namely, the difficulty in improving a yield of CNTs.

Growing community of inventors

Daejeon, South Korea

Kyung Yeon Kang