Aqueous electrolyte presents in batteries have high ionic conductivity. They are economic, non-flammable and offer high energy density. However, restricted thermodynamic electrochemical stable potential window of water and its spilling suppresses the use of these batteries. To address these problems, development of a polymer-based electrolyte system is an upcoming area of research. Even, the uses of sodium salts in battery electrolytes are gaining importance over lithium salts due to their abundance and economic feasibility. The present study examines the self-aggregation of star block copolymer Tetronic® 1107 in aqueous medium in the presence of sodium salts viz. sodium chloride, sodium fluoride, sodium nitrate, sodium hexafluoro phosphate and disodium hydrogen phosphate with different anions by cloud point (CP), gelation, dynamic light scattering (DLS) and small angle neutron scattering (SANS). Conductivity and DC polarization measurements are also performed for polymeric systems in the absence and also in the presence of these salts. The gelation behaviour of the block copolymer to reduce leakage problems and proper ionic conductivity of it in the presence of sodium salts make the system a credible choice as a polymer gel electrolyte (PGE). Display omitted •A systematic study defining the role of Tetronics® 1107 as a PGE component is reported.•Phase and gelation behaviour of block copolymer under the influence of sodium salts are discussed.•DLS and SANS are utilised for identifying shape and size of the micelles.•Ionic conductivity, transport number measurements are performed for polymer in the presence and absence of salts.•Decrease of CP and an enhanced micellar size and conductivity is observed in the presence of salts.