Method for laser treatment of a lithium surface

A method for treating a surface of a strip or film, said strip or film being made of lithium or a lithium-based alloy, the method comprising a step of laser beam irradiation of at least a portion of a surface of said strip or film, the irradiation step being carried out under controlled atmosphere, the entire surface area of said at least one surface portion of the strip or film being irradiated by the laser beam,

• the method comprising a succession of trajectories of the laser beam above said at least one portion of a surface of the strip or film, the spacing between two trajectories being less than the size of the focal spot of the laser, so that the portion of the surface irradiated by the laser beam does not include a geometric pattern, regardless of the angle of observation, and is modified without forming edges.