パルスCVI 法によるリチウムイオン電池用電極の作製

Abstract

Using pressure-pulsed chemical vapor infiltration (PCVI) technique, TiN was partially infiltrated at 850 °C from gas system of TiCl4(1%)-N2(20%)-H2 into the highly porous carbon preforms prepared by the carbonization of commercial cotton-cloth, cotton-wool and wood at 1000 °C in Ar for 4 h. After 10000 pulses of PCVI, electro-conductive porous substrates were obtained, which had the porosity of 80 % and more, the resistivity of 0.1 mΩ cm, and the average pore sizes of 10 - 40 μm. The positive and negative electrodes were prepared by PCVI of titanium sulfide and pyrolytic carbon into the electro-conductive porous substrates, respectively. The electrodes possessed the three-dimensionally continuous current paths without the organic binders and the additional conductive fillers. Pyrocarbon or titanium sulfide films adhered tightly to the substrate TiN as current collector. It is expected that these macro-structures of electrodes are effective in improving the charge/discharge performance at high rate.