Performance of a Li-Polyimide Battery with Electrolytes of Various Types

Abstract

—The effect of various types of electrolyte on the behavior of lithium-polyimide batteries was studied. The electrolyte systems used included the liquid 1 M LiPF6 electrolyte in ethylene carbonate/dimethyl carbonate (1: 1), plasticized polymer electrolyte based on the polyvinylidene fluoride copolymer with hexafluoropropylene, and nanocomposite electrolyte with SiO₂ nanoparticles introduced in different amounts. The structure rearrangement of polyimide during lithiation—delithiation was studied by cyclic voltammetry (CV), charge—discharge cycling, and quantum—chemical modeling using four types of electrolyte. The use of the polymer and nanocomposite electrolyte was shown to increase the discharge capacity of the polyimide cathode compared to that of the cell with liquid electrolyte, but the structural degradation of the polyimide cathode cannot be avoided.