A method for preparing a multilayer material based on active lithium, by depositing a film of active lithium on a protective layer at a sufficient speed so that substantially no oxidation of the lithium occurs, and/or during a sufficient time for the adhesion of the lithium to develop after contact with the protective layer. The multilayer material, when incorporated in an electrochemical battery as an anode, has excellent impedance stability and no formation of dendrites during the cycling. Batteries where the anode is the multilayer material are particularly efficient in terms of their coulomb efficiency.
