Ni-PLATED STEEL FOIL FOR NICKEL HYDROGEN SECONDARY BATTERY COLLECTORS, NICKEL HYDROGEN SECONDARY BATTERY COLLECTOR, AND NICKEL HYDROGEN SECONDARY BATTERY

摘要

The present invention provides a high-strength steel foil for nickel hydrogen secondary battery positive/negative electrode collectors, said high-strength steel foil being thin and strong, while using a lightweight and economical steel foil. This high-strength steel foil exhibits excellent rust preventive properties and metal dissolution resistance. The present invention also provides a high-strength steel foil for nickel hydrogen secondary battery positive/negative electrode collectors, said high-strength steel foil exhibiting excellent elongation properties. An Ni-plated steel foil for hydrogen secondary battery collectors, said Ni-plated steel foil containing, in mass%, from 0.0001% to 0.0200% of C, from 0.0001% to 0.0200% of Si, from 0.005% to 0.300% of Mn, from 0.001% to 0.020% of P, from 0.0001% to 0.0100% of S, from 0.0005% to 0.1000% of Al, from 0.0001% to 0.0040% of N and 0.800% or less of Ti and/or Nb, respectively, with the balance being made up of Fe and impurities, while having an Ni-plating layer on both surfaces. The respective thicknesses of the Ni-plating layers on both surfaces of the Ni-plated steel foil are 0.15 μm or more; the thickness of the Ni-plated steel foil is from 5 μm to 50 μm; the tensile strength of the Ni-plated steel foil is more than 400 MPa but not more than 1,200 MPa; and both surfaces of the Ni-plated steel foil have a surface defect area ratio of 5.00% or less.