Electrolytic Copper Foil for Lithium Rechargeable Battery and Process for Producing the Copper Foil

Abstract

An electrolytic copper foil for a lithium rechargeable (secondary) battery, wherein the 0.2% proof stress is 18 to 25 kgf/mm2 and the elongation rate is 10% or more; and a process for producing an electrolytic copper foil for a lithium rechargeable battery, wherein an electrolytic copper foil whose 0.2% proof stress is 18 to 25 kgf/mm2 and elongation rate is 10% or more is manufactured by subjecting the electrolytic copper foil to an annealing treatment at a temperature within the range of 175° C. to 300° C. The present invention provides such an electrolytic copper foil used for a lithium rechargeable battery that has good proof stress and elongation rate and will not be easily broken due to electrode breakage caused by charge and discharge of the lithium rechargeable battery; and the invention also provides a process for producing such an electrolytic copper foil.

Dependencies are inferred from the claim text.