The high cost of lithium raw materials and the limitation of its natural recourses call for new sources of high-capacity batteries. Sodium systems are alternative to lithium ones. Sodium is extremely common element, and its raw materials are hundred of times cheaper than lithium. Now, the design of Na – containing batteries has many attempts, but some technologic difficulties leaved this question open. One of the ways of solving this problem is using of the complex electrolytes. So, electrochemical properties of the electrolyte system - sodium bis[salicylato(2-)]-borate - γ-butyrolactone (NaBSB-GBL) in the temperature range 17-60 °C were studied in this work using electrochemical complex Autolab. The CVA studies of NaBSB-GBL electrolytes have found that the electrochemical resistance window had been about 4.0 V. Fixed temperature dependence of the conductivity in NaBSB-GBL solutions with a concentration of 0.25-0.75 mol/l have established the appearance of a pseudocapacity at the electrode/solution interface at temperatures below 20 °C, which value had been increased linearly with increasing of temperature. The opposite effect is observed in the concentration of NaBSB 1 M/l. In this concentration range at temperatures up to 60 °C the value of pseudo-capacity insignificantly increases, and at 60 °C this value tended to value of less concentrated solutions. Obtained dependence has a nonlinear character with a minimum point in the temperature range 40 °C. It was proposed the scheme of charge transfer based on our study: coexistence of two transfer pathways, namely hoping and Faraday ones (fig 1). The contribution of the hoping transfer through the active sites of the inorganic polymer ensures the high ionic conductivity of the system, and the Faraday mechanism through the bulk determines the appearance of a pseudo-capacitance. The increasing of the temperature leads to the disorder of the polymer structure and increased the contribution of charge and mass transfer through the bulk of electrolyte. Finally, it caused the rising of leakages and energy loss.  Fig. 1. Chart of charge transfer in NaBSB-GBL electrolytes  It was shown that studied system could be used in a secondary battery with high voltage (up to 3.65 V).