Korea Kumho Petrochemical Co., Ltd.

Sang-Hyo Ryu

Youngchan Jang

Wan Sung Lee

Hyun-Kyung Sung

Dong Hwan Kim

Namsun Choi

Jee-Hwan Jang

Dong-Hwan Kim

Hyung-Song Lee

Im Goo c/o 106-1301 Hanbit Apt Choi

Dong Hwan c/o 101-507 Daelim Dure Apt Kim

Namsum c/o 110-307 Daelim Dure Apt Choi

Youngchan c/o 105-906 Chonggu Narae Apt Jang

Seung Yeon c/o 202 Woojoo Villa Jang

Kwangyoung c/o 505-1601 Yeolmae Maeul Apt Lee

The present invention relates to a process for preparing catalyst composition for the synthesis of carbon nanotube with high yields using the spray pyrolysis method. More particularly, this invention relates to a process for preparing catalyst composition for the synthesis of carbon nanotube comprising the steps of i) dissolving multi-component metal precursors of catalyst composition in de-ionized water; ii) spraying obtained catalytic metal precursor solution into the high temperature reactor by gas atomization method; iii) forming the catalyst composition powder by pyrolysis of gas atomized material; and iv) obtaining the catalyst composition powder, wherein said catalyst composition comprises i) main catalyst selected from Fe or Co, ii) Al, iii) optional co-catalyst at least one selected from Ni, Cu, Sn, Mo, Cr, Mn, V, W, Ti, Si, Zr or Y, iv) inactive support of Mg. Further, the catalyst composition prepared by this invention has a very low apparent density of 0.01&#x2dc;0.50 g/ml as well as the catalyst composition affords high production yield (1,000&#x2dc;1,800%) of carbon nanotube.

Process for preparing catalyst composition for the synthesis of carbon nanotube with high yields using the spray pyrolysis method

The present invention relates to a catalyst composition for the synthesis of thin multi-walled carbon nanotube(MWCNT). More particularly, this invention relates to a multi-component metal catalyst composition comprising i) main catalyst of Co and Al, ii) inactive support of Mg and iii) optional co-catalyst at least one selected from Ni, Cr, Mn, Mo, W, Pb, Ti, Sn, or Cu. Further, the present invention affords thin multi-walled carbon nanotube having 5&#x2dc;20 nm of diameter and 100&#x2dc;10,000 of aspect ratio in a high yield.

Catalyst composition for the synthesis of thin multi-walled carbon nanotube

The present invention relates to a catalyst for preparing a carbon nanotube having desired apparent density by controlling the adding amount of co-precipitating agent in the process of preparing a catalyst in order to obtain a catalyst having a minimized particle size. More specifically, this invention relates to a catalyst for preparing carbon nanotube having desired apparent density based upon the reverse-correlation between the amount of co-precipitating agent added in the process of preparing catalyst and the apparent density of catalyst. The carbon nanotube prepared by the catalyst having low apparent density shows excellent electrical conductivity and highly uniformed dispersion in the polymer/carbon nanotube composite.

Catalyst for preparing carbon nanotubes by controlling its apparent density

The present invention relates to a catalyst composition for preparing carbon nanotube containing multi-component support materials of amorphous Si, Mg and Al as well as a bulk scale preparation process for preparing carbon nanotube using said catalyst composition. More specifically, this invention relates to a process for preparing carbon nanotube using the catalyst composition comprising a transition metal catalyst and support materials of amorphous Si, Mg and Al.

Catalyst for preparing carbon nanotube comprising multi-component support materials containing amorphous silicon particles and the bulk scale preparation of carbon nanotube using the same

The present invention relates to a catalyst composition for the synthesis of thin multi-walled carbon nanotube (MWCNT) and a method for manufacturing a catalyst composition. More particularly, this invention relates to a multi-component metal catalyst composition comprising i) main catalyst of Fe and Al, ii) inactive support of Mg and iii) optional co-catalyst at least one selected from Co, Ni, Cr, Mn, Mo, W, V, Sn, or Cu. Further, the present invention affords thin multi-walled carbon nanotube having 5&#x2dc;20 nm of diameter and 100&#x2dc;10,000 of aspect ratio in a high yield.

Catalyst composition for the synthesis of thin multi-walled carbon nanotube and its manufacturing method

The present invention relates to a method for evaluating an initial capacity of secondary batteries and, more specifically, to a method for evaluating an initial capacity of secondary batteries that involves mathematical operation of specific internal resistance components obtained from an equivalent circuit model of an impedance spectrum measured for a short time period instead of using direct discharge characteristics, thereby allowing selection of batteries having a different initial discharge characteristic.

Method for evaluating capacity of secondary battery using mathematical calculation of specific resistance components of equivalent circuit model fitted from impedance spectrum

A method for grouping unit cells of a similar impedance spectrum uses pattern matching technology to optimize the performance of a battery pack made of primary or secondary batteries as the unit cells connected in series, in parallel or in combination of them. To make an optimal battery pack with unit cells of a different internal characteristic, the method includes measuring the impedance spectrum of the individual unit cell in a wide frequency region at the same temperature and in the same state of charge (SOC), digitizing the difference in impedance spectrum among the unit cells into a relative value using the pattern matching technology, and selecting unit cells of a most similar impedance spectrum (i.e., a smallest relative difference in impedance spectrum) to make a battery pack.

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Daejeon, South Korea

Sang-Hyo Ryu