The present invention relates to polymers used as rolling lubricating agents, to compositions comprising said polymers, and to alkali metal films including the polymers or compositions on the surface(s) thereof. The use of said polymers and compositions is also described for strip-rolling alkali metals or alloys thereof in order to obtain thin films. Methods for producing said thin films, which are suitable for use in electrochemical cells, are also described. The present invention proposes an improved lubricant according to formula I, which, for example, achieves enhanced conductivity, and/or enables the production of electrochemical cells having an improved life span in cycles.