Towards the mechanism of Li+ ion transfer in the net solid polymer electrolyte based on polyethylene glycol diacrylate–LiClO4

Abstract

Ion transport in the new three-dimensional network polymer electrolytes that are completely amorphous in the solid state has been studied on the example of the matrix model with a monomer—polyethylene glycol diacrylate, cross-linked by radical polymerization. The nature of ionic conductivity in solid polymer electrolytes based on polyethylene glycol diacrylate at different concentrations of salt LiClO4 was studied by methods of electrochemical impedance, differential scanning calorimetry analysis, Fourier transform infrared spectroscopy and quantum chemical modeling. The maximum value of conductivity in the range of 20–100 °C is realized at 20 wt% content of LiClO4. The reason for the low conductivity of the SPE studied is the small degree of dissociation of contact ion pairs. At the increase in the salt content associates of contact pairs Li+ClO4−, dimers and trimers (at LiClO4 >20 wt%) are formed. The appearances of trimers are accompanied by a decrease in conductivity due to lowering of contact pair content.