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In this work, a poly(vinylidene fluoride) (PVDF)-based copolymer is synthesized by grafting two kinds of monomer, 2, 2, 3, 4, 4,-hexafluorobutyl methacrylate (HFMA) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS), onto the PVDF powder with pre-irradiation grafting copolymerization. Then a new single lithium-ion conducting polymer electrolyte (SIPE) is prepared by solution casting of the radiation grafted PVDF-based copolymer powder with subsequent lithiation process. Its chemical structure, crystal form, and membrane morphology are characterized by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), etc. The mechanical properties exhibit the elongation at break of 72% and the tensile strength of 28 MPa. Comparatively high values of ionic conductivity, up to 2.08 × 10−5 S cm−1 at 30 °C, are obtained, combined with lithium-ion transference number of 0.93 and stable electrochemically oxidation voltage as high as 4.4 V vs Li/Li+. Except for these promising features, the SIPE cell with lithium ion conduction network has a stable charge/discharge cycling performance with various C-rates at room temperature. As-prepared SIPE shows a great prospect for the application in lithium-ion batteries.

A novel way to manufacture single-ion conductor gel polymer electrolyte was reported in this work. Firstly, the γ-ray co-irradiation grafting is introduced to solve the difficulty on how to prepare single-ion conductor with considerable physical and chemical properties. Here, the PVDF-HFP is chosen as the polymer backbone for its excellent performance for polymer electrolyte while 2-acrylamido-2-methylpropanesulfonic acid (AMPS), a common and easily obtained double bond monomer with higher degree of negative charge delocalization, is chose to be the grafting monomer. To further promote the dissociation of Li+ ions from the polyanions, the prepared grafting copolymer is spun into a nonwoven membrane with high porosity. Besides, the grafting copolymer nonwoven fabric transforms the crystal form of PVDF-HFP to a better β-phase with higher polarity and maintains an approximative thermal stability. After plasticized by EC/DMC solvent, this prepared single-ion conductor gel polymer electrolyte (SIC-GPE) presence a high lithium-ion transference number (LTN) of 0.97 with an outstanding electrochemical stability and an appropriate battery performance.