CATHODE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY AND BATTERY USING THE ANODE

摘要

PURPOSE: A nonaqueous electrolyte secondary battery is provided, to increase the lifetime, to improve the energy density and the electrical power by employing a sheet-shaped anode with high density of active material and excellent workability. CONSTITUTION: The nonaqueous electrolyte secondary battery comprises a sheet-shaped cathode(2) containing a lithium-containing transition metal oxide as an active material and a particulate binder; a sheet-shaped anode(3) containing a carbon material; a separator(4) interposed between the anode and the cathode; and a nonaqueous electrolyte containing lithium salts, wherein the anode and the cathode are wound by the separator to form an electrode assembly and the density of the active material in the cathode is 3.0-4.0 g/ml. Preferably the binder comprises an elastomer containing a 2-ethylhexylacrylate unit, an acrylic acid unit and an acrylonitrile unit. The cross-section of the electrode assembly is ellipse-shaped and the ratio of a longer axis to a shorter axis of the ellipse is 4-10.