We have been applying our original in-situ material processing technology called ‘Ultra-Centrifuging (UC) Treatment’ to prepare a novel ultrafast nano-crystalline Li4
(nc-LTO) /carbon nano fiber (CNF) composite electrode for the generation-II capacitive energy storage device of ‘Nanohybrid Capacitor’ producing more than triple
energy density of a conventional electrochemical capacitor.
For the further improvement in the energy density of ‘Nanohybrid Capacitor’, LTO alternatives are needed. Among different candidates, TiO2
(B) possesses several advantages such as its 2-folds theoretical capacity (335 mAh g-1
) of LTO
(175 mAh g-1
) and the comparable redox potential (1.6 V vs.
). In addition, TiO2
(B) is an industrially attractive material because of its inexpensive raw materials and its environmentally benign synthesis using only aqueous solution (e.g., water-soluble complexes 
) without any Li-sources.[2-4]
(B) has intrinsic problems; its low electronic conductivity and Li+
diffusivity due to the b-axis oriented growth of TiO2
. In this report, we successfully synthesized b-axis shortened and hyper-dispersed nc-TiO2
(B)/CNF composites, which has a potential to substitute nc-LTO/CNF as a negative electrode of ‘Nanohybrid capacitor’. Inhibition of b-axis growth and hyper dispersion of TiO2
(B) into the carbon matrix were simultaneously achieved by the UC treatment and the subsequent hydrothermal method 
. The prepared nc-TiO2
/CNF exhibited 236 mAh g-1
(active material) at high rate of 300 C, which even exceeds that of nc-LTO/CNF composites. A significant decrease of peak intensity corresponding to the C-site intercalation around 2 V vs
indicates that the Li+
was directly accommodated into A1 and A2 site of TiO2
(B) owing to the limitation of b-axis growth. Furthermore, the combined analysis of the N2
adsorption experiment and electochemical characterization suggests that the "dispersibility" of nc-TiO2
(B) on CNF matrix correlates closely with its electrochemical performance.
 K. Naoi, et al., Energy & Environ. Sci., RSC, 5, (2012) 9363.
 a) M. Kobayashi, et al., Chem. Mater., 19, (2007) 5373.
 A. R. Armstrong et al., Chem. Mater., 22, (2010), 6426.
 Y. Ren, et al., Angewandte. Chem. Int. Ed, 51, (2012) 2164.