ИСТИНА

Polymer electrolytes have numerous advantages over traditional liquid electrolytes for many electrochemical applications including advanced metal-ion batteries. However, they usually have low conductivity, which may limit their practical use. Finding ways to improve the conductivity of polymer electrolytes is an important scientific and technical problem. In this work, a polyacrylonitrile-based gel-polymer electrolyte for sodium-ion batteries is described that features sodium-ion conductivity greater than 1•10-3 Ом-1 см-1 at room-temperature. Complete sodium-ion cells with these gel-polymer electrolytes are tested. They are capable of withstanding several hunderds charge-discharge cycles without significant deterioration of the parameters of the electrolyte both at room temperature and at -20C. Practical aspects of conductivity measurements in polymer electrolytes are also discussed, including such issues as the cell design, types of electrodes to be used, treatment and interpretation of the impedance data to extract the electrolyte conductivity. The work was supported by the Russian Science Foundation, grant no. 17-73-30006.