The present invention relates to a method for pretreatment of substrates containing
copper and / or alloys thereof, the method comprising at least step 1), namely contacting at least one surface of the at least one substrate, said surface being made of
copper and / or at least one
alloy thereof, at least in portion with an aqueous composition and thereby forming a film at least in portion on said surface, wherein the aqueous composition comprises, besides water, at least one of constituents a1) and a2), namely at least one of
zirconium,
titanium and
hafnium cations as constituent(s) a1) in an amount in a range of from 5 to 2000 mg / L, and / or at least one organosilane and / or a
hydrolysis and / or condensation product thereof as constituent(s) a2), wherein contacting step 1) is performed in an
electrolytic cell arrangement with the substrate made of
copper and / or alloys thereof being the
cathode during performance of step 1), a method of applying at least one
coating film onto the surface of the pretreated substrate, a substrate obtainable by one of these methods, current collectors, conductors, copper clad laminates,
anode materials and battery cells obtainable therefrom, and to a use of aforementioned aqueous composition for electrolytically forming films on substrates made of copper and / or alloys thereof.