Incorporation of Poly(Ionic Liquid) with PVDF-HFP-Based Polymer Electrolyte for All-Solid-State Lithium-Ion Batteries

Abstract

A solid-state polymer electrolyte membrane is formed by blending poly(vinylidene fluoride-co-hexafluoropropylene) with the synthesized copolymer of poly(methyl methacrylate-co-1-vinyl-3-butyl-imidazolium bis(trifluoromethanesulfonyl)imide, in which lithium bis(trifluoromethane)sulfonimide molecules are applied as the source of lithium ions. The accordingly formed membrane that contains 14 wt.% of P(MMA-co-VBIm-TFSI), 56 wt.% of PVDF-HFP, and 30 wt.% of LiTFSI manifests the best electrochemical properties, achieving an ionic conductivity of 1.11 × 10−4 S·cm−1 at 30 °C and 4.26 × 10−4 S·cm−1 at 80 °C, a Li-ion transference number of 0.36, and a wide electrochemical stability window of 4.7 V (vs. Li/Li+). The thus-assembled all-solid-state lithium-ion battery of LiFePO4/SPE/Li delivers a discharge specific capacity of 148 mAh·g−1 in the initial charge–discharge cycle at 0.1 C under 60 °C. The capacity retention of the cell is 95.2% after 50 cycles at 0.1 C and the Coulombic efficiency remains close to 100% during the cycling process.

Understanding the Electrochemical Performance of Spongy C–F Derivative Chains as an Effective Anion Trapping Composite Matrix for Li-Ion Batteries

“…Meanwhile, further work should be needed to improve the electrochemical stability of the CPEs to be competent with high-potential cathodes. 73,74 XPS was employed to investigate the interactions of h-BN with PF 6 − ions. The O 1s and survey scan spectra are shown in Figure S7a,b.…”

“…78,79 Li-ion transference number is considered an essential factor in appreciating the performance of CPEs. 74 For legitimate evaluation, the current−time curve of DC polarization and the corresponding AC impedance responses of the fabricated cells were investigated. The chronoamperometry profile of the prepared PCBN-CPE symmetric cell is shown, and corresponding impedance spectra are inserted in Figure 9a.…”

“…This finding implies that adding h-BN particles increased the electrochemical stability of the CPE membranes. Meanwhile, further work should be needed to improve the electrochemical stability of the CPEs to be competent with high-potential cathodes. , …”

Ionic liquids in the scope of lithium-ion batteries: from current separator membranes to next generation sustainable solid polymer electrolytes

“…58 A more complex poly(methyl methacrylate- co -1-vinyl-3-butyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide P(MMA- co -VBIM-TFSI) was synthesized and combined with PVDF-HFP with a good discharge capacity (148 mA h g −1 ) at 60 °C, and a good capacity retention of 95% after 50 cycles. 89 Dimethylamine-containing Poly ILs with polysubstituted benzene units were synthesized using ion exchange processes with lithium salts. This approach provided a high charge density structure with high thermal stability and good battery operation at room temperature.…”

Phase behavior of binary and ternary fluoropolymer (PVDF-HFP) solutions for single-ion conductors

“…For example, PVDF-HFP has been blended with other molecules such as poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), poly(vinyl acetate) (PVAc), poly(vinyl chloride) (PVC), thermoplastic polyurethane (TPU), poly(methyl methacrylate-co-acrylonitrile-co-lithium methacrylate) (PMAML), poly(ionic liquid), polysiloxane, and carboxymethyl cellulose (CMC). 8,[12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] Here, it is notable that these polymer electrolytes have been developed for solid-state batteries (SSBs), which are one of the post-lithium-ion batteries (PLIBs) including sodium-ion batteries (SIBs), lithium-sulfur batteries (LSBs), and lithium-air batteries (LABs). [27][28][29][30][31][32] Specically, the peruoropolyether-based block copolymer electrolyte was designed for ultra-stable SIBs.…”