Quasi-Solid-State Electrolyte Synthesized Using a Thiol–Ene Click Chemistry for Rechargeable Lithium Metal Batteries with Enhanced Safety

Abstract

Liquid electrolytes currently used in lithium-ion batteries have critical drawbacks such as high flammability, high reactivity toward electrode materials, and solvent leakage. To overcome these issues, most recent research has focused on synthesis and characterization of highly conductive gel-type polymer electrolytes containing large numbers of organic solvents in the polymer matrix. There are still many hurdles to overcome, however, before they can be applied to commercial-level lithium-ion batteries. Since a large amount of organic solvent is required to achieve high ionic conductivity, battery safety is not significantly enhanced. In our study, we synthesized highly conductive quasi-solid-state electrolytes (QSEs) containing an ionically conductive oligomer (polycaprolactone triacrylate) and a small amount of organic solvent by employing click chemistry. In the QSE, polycaprolactone participates in dissociation of lithium salt and migration of lithium ions, resulting in high ionic conductivity. The Li/ LiNi 0.6 Co 0.2 Mn 0.2 O 2 cell that used this QSE exhibited good cycling performance and enhanced thermal stability, and durability; no organic solvent leakage was observed even under high pressure.

Bifunctional Surface Coating of LiAlO2/Si1–xAlxO2 Hybrid Layer on Ni-Rich Cathode Materials for High Performance Lithium-Ion Batteries

“…The potential interval (Δ V ) of NCM@LSAO at each cycle is lower than that of NCM and NCM@SO. Meanwhile, as compared to NCM and NCM@SO, the CV curves of NCM@LSAO overlap well in the subsequent cycles. − Therefore, these results suggest that the LiAlO 2 /Si 1– x Al x O 2 surface modification could effectively reduce the polarization degree in the electrochemical process.…”

Fabrication of Borate-Based Porous Polymer Electrolytes Containing Cyclic Carbonate for High-Performance Lithium Metal Batteries

“…Furthermore, the peaks can be fitted into three bands, which are free TFSI ions, contact ion pair, and aggregates. 63,64 The Raman spectra of poly(B-Vd)-LiTFSI show that the proportion of free TFSI anions is higher than that of PVDF-LiTFSI or LiTFSI, demonstrating that the interactions between the anions and boron moieties promote the dissociation of lithium salt.…”

Nonflammable Gel Polymer Electrolyte with Ion-Conductive Polyester Networks for Sodium Metal Cells with Excellent Cycling Stability and Enhanced Safety

“…PCL triacrylate (PCL-TA) was synthesized by nucleophilic acyl substitution reaction between PCL-triol and acryloyl chloride, as reported in our previous work . A quaternary solvent mixture was composed of EC, FEC, PC, and TMP (40:20:40– x : x , by volume), and 0.8 M NaFSI was dissolved in the mixed solvent to prepare the liquid electrolyte.…”