Poly(ionic liquid) block copolymers based on TFSI or imidazole ionic liquids are innovative classes of polymers electrolytes because they possess advanced properties of ionic liquids like thermal stability, non-flammability, high ionic conductivity while preventing their inherent problems such as leakage, low mechanical strength [1]. Most studies of neat poly(ionic liquids) (without salts) have focused on conductivity [2,3], some of them interpreting the direct current conductivity based on ion-pair repetitive formation/dissociation process and the translational diffusion of the counteranions [4]. Besides that, by elevating temperature, poly(ionic liquids) electrolytes (with salts) exhibit an increase in lithium transport number which is interpreted by the improvement of ion dissociation [5]. These have given the motivation to use 7Li and 19F NMR longitudinal relaxation and self-diffusion coefficients measurements (by PFG-NMR) to study the dynamics of ionic species (Li+, FSI-, TFSI-) in poly(ionic liquids) electrolytes. The results are expected to elucidate the ions transport mechanism, which will help to design novel electrolytes for lithium-metal batteries.