A method for heat treatment of a cold rolled strip with a surface coating of Ni and/or Co and incorporated non-metallic elements C and/or S, if need be with the addition of Fe, In, Pd, Au and/or Bi, whereby the cold rolled strip has a low carbon content. Since the compounds of C, S, N and P deposited on the grain boundaries bring about the most micro-cracks with the surface coating metal if no recrystallization takes place, the temperature of the heat treatment should be selected lower than the recrystallization temperature and higher than the precipitation temperature. With a recrystallization, the grain sizes would easily attain the thickness of the coating so that the embrittled compounds would migrate with the grain boundaries out of the coating. Due to the choice of temperature of the heat treatment of the surface coating of the invention, in contrast, an optimal embrittlement of the grain boundaries is guaranteed, which is especially advantageous in the manufacture of battery cans. Furthermore the sheet metal which can be manufactured in accordance with the invention and the corresponding battery can are described.