Abstract:
PURPOSE: A negative electrode active material is provided to improve initial charging and discharging efficiency, capacity maintenance, and high voltage properties of a high capacity lithium battery by using multi-layered nanotubes. CONSTITUTION: A negative electrode active material comprises: an inner layer which comprises an inner surface of metal nanotubes, and an outer layer which comprises an outer surface of the metal nanotubes. The inner layer comprises a first metal of which an atomic number is 13 or more. The outer layer comprises multilayered metal nanotubes which comprise a second metal different with the first metal. The second metal has a lower resistivity than the resistivity of the first metal. The diffusivity of lithium ions is high and volume expansion at charging is low. [Reference numerals] (AA) Metal oxide nanorod; (BB) Conductive substrate; (CC) First metal coating; (DD) Metal oxide template etching; (EE) First metal nanotube; (FF) Second metal coating; (GG) First metal; (HH) Second metal; (II) Inner and outer layer structures
Abstract:
An electrode for a secondary battery is provided to improve the capacity of electrode and cycle of a battery by improving the uniformity of an active material layer through the printing of low point ink. An electrode for a secondary battery comprises a current collector(10) and an active material layer formed by printing and drying ink(11) having the viscosity of 500 mPa . s on the current collector. The surface roughness Ra the current collector is 0.025-1.0 micron. The thickness the active material layer is 0.1-10 micron. The current collector is surface-treated with UV or the plasma.