METAL OXIDE ELECTRODES COATED WITH A POROUS METAL FILM A POROUS METALOXIDE FILM OR A POROUS CARBON FILM ITS FABRICATION METHOD AND LITHIUM SECONDARY BATTERY USING IT

摘要

PURPOSE: A metal oxide electrode coated with porous metal, metal oxide or carbon thin film, its preparation method and a lithium secondary battery using the electrode are provided, to improve the capacity of a battery, the efficiency of charging/discharging and the lifetime. CONSTITUTION: The metal oxide electrode is such that it is coated with a thin film comprising porous metal, porous metal oxide or porous carbon by the thickness of several Angstrom to several micrometers. The method comprises the steps of placing a metal oxide electrode roll in a vacuum chamber; evaporating metal, metal oxide or carbon to coat the electrode with porous metal, porous metal oxide or porous carbon with unwinding the electrode from the roll at regular speed and winding it to another roll; and placing the electrode at a specific temperature under vacuum to stabilize the electrode. Preferably the porous metal is selected from the group consisting of Li, Al, Sn, Bi, Si, Sb, Ni, Cu, Ti, V, Cr, Mn, Fe, Co, Zn, Mo, W, Ag, Au, Pt. Ir, Ru or their alloys; and the metal oxide electrode comprises an active material which is prepared by using LiCoO2, LiMn2O4, LiNiO2, V6O13 or V2O5.