ELECTRODEPOSITED COPPER FOIL AND ELECTRODEPOSITED COPPER FOIL FOR SECONDARY BATTERY COLLECTOR

摘要

PURPOSE: Provided are an electrodeposited copper foil with a low surface roughness and an electrodeposited copper foil suitable for the collector of a cathode of a secondary battery. CONSTITUTION: The electrodeposited copper foil has a surface roughness at a deposition surface at ordinary temperature smaller than 2.5 micrometer in terms of 10 point average roughness Rz, a minimum distance between base foil peaks of at least 5 micrometer, an ordinary temperature tensile strength of not more than 40 kg/mm2, and a drop in ordinary temperature tensile strength after heat treatment at 130 deg.C for 15 hours of less than 15%. The foil does not soften under heat after the heat treatment. The elongation rate at ordinary temperature is at least 14% at a thickness of 35 micrometer and the elongation rate increases along with a rise in temperature in an atmosphere from ordinary temperature to 200 deg.C.