Abstract:High tensile strength copper foil can match the rolling process of high-energy density batteries. Terahydrozolinethioketone was added into the additive for producing 6 μm copper foil. The brightness, glossines, tensile strength and roughness of copper foil were tested. XRD, SEM and 3D Superdepth of field were utilized to analyse the copper foils.The highest tensile strength of copper foil was produced when the amount of terahydrozolinethioketone was 10% of the mass ratio of bis-(sodium sulfopropyl)-disulfide in the original formula, the tensile strength could reach 420 MPa. After being adsorbed on the surface of the cathode roller, unsaturated double bonds and N atoms, p-electrons were repelled by strong negative electric field, which made the ability of the S and N atoms improved. Stable complex were formed when Cu2+ with sp3 hybrid empty orbitals migrated to the electrode surface, the tensile strength of the copper foil was improved.