The data presented in this article are related to the research article entitled “Structure and electrochemical characterization of SnO_x/Sn@MWCNT composites formed by pulsed ion beam irradiation” (Korusenko et al., 2019). This article presents the effect of irradiation by pulsed ion beam (PIB) irradiation at various modes on the structure multi-walled carbon nanotubes (MWCNTs) and composites based on MWCNTs and tin oxide as well as cycling performance of these composites. The article also presents the results of the analysis of the structure of the electrodes, obtained on the basis of the initial and irradiated composites.