The Effect of TiO₂ Nanoparticles and the Liquid-Phase Therapy on the Resistance of the Interphase Lithium/Polymer Electrolyte with the Introduction of Ionic Liquid

It is studied how the treatment of a metal lithium surface with a 1 M LiN(CF₃SO₂)₂ solution in the 1,3-dioxolane/1,2-dimethoxyethane (2 : 1) mixture affects the resistance of the interphases formed by lithium with the polymer and nanocomposite electrolytes based on the 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid. The liquid-phase therapy is shown to reduce the resistance at the Li/electrolyte interphase by a factor of 2.5 at room temperature and extend the working temperature range to –30°C. The introduction of TiO₂ nanoparticles into the polymer electrolyte, along with the liquid-phase therapy of both the cathode and the Li-anode, provides a high and stable discharge capacity of the Li//LiFePO₄ battery for 100 charge–discharge cycles.