Solvation-Free Fabrication of PEO/LiTFSI/SiO₂ Composite Electrolyte Membranes with High Ionic Conductivity Based on a Novel Elongational Flow Field

Abstract

Poly­(ethylene oxide) (PEO)-based composite electrolyte membranes, which silica (SiO2) and lithium bis­(trifluoromethylsulf)­imide (LiTFSI) were introduced into, were successfully prepared by a self-developed eccentric rotor mixer based on an elongational flow field. Characterization results of electrolyte membranes showed that the eccentric rotor mixer can realize the uniform dispersion of LiTFSI in all electrolyte membranes. This produced a high ionic conductivity of the electrolyte membrane. Among all as-prepared membranes, the ionic conductivity of PEO5 exhibited the highest value of 2.96 × 10–4 S·cm–1 at room temperature due to reaching an extremely uniform dispersion of SiO2. After 90 charge–discharge cycles, the Coulomb efficiency of the LPF/PEO5/Li was still close to 100%, and the discharge specific capacity weakly decreased, revealing an extremely good electrochemical performance of PEO5. Therefore, the eccentric rotor mixer provides an effective strategy for facilitating the development of high-efficiency all-solid-state lithium-ion batteries.

Impact of Nano‐sized Inorganic Fillers on PEO‐based Electrolytes for Potassium Batteries

“…reported [59] room temperature ionic conductivities of up to 0.22 mS cm −1 for a PEO 9 LiTFSI 1 composite with 10 wt.% porous Al 2 O 3 (104 μm particle size; 155 m 2 g −1 ). Similar values were reported in a recent study by Yang et al [60] . for SiO 2 (7–40 nm) composites (PEO 15 LiTFSI 1 ).…”

“…For example, Jayathilaka et al reported [59] room temperature ionic conductivities of up to 0.22 mS cm À 1 for a PEO 9 LiTFSI 1 composite with 10 wt.% porous Al 2 O 3 (104 μm particle size; 155 m 2 g À 1 ). Similar values were reported in a recent study by Yang et al [60] for SiO 2 (7-40 nm) composites (PEO 15 LiTFSI 1 ). This is largely in agreement with previous conductivity comparisons [18,61] between the monovalent cations Li + , Na + and K + , where PEO-based electrolytes with ATFSI (A = Li, Na, K) salts also displayed similar ionic conductivities, independent of the cation (an increase in transference number for larger cations could be shown by Oteo et al [61] ).…”

“… In literature, the effect of ceramic fillers beyond reported improvements of mechanical properties is controversially discussed [38,62] . For Li‐SPEs, ceramic fillers were studied in a variety of different electrolyte salts for PEO‐LiX composite electrolytes (X=BETI, [62,63] TFSI [59,60,64] or triflate (SO 3 CF 3 − ) [39] ). The composition with an EO:Li molar ratio of 20 : 1 seemed particularly favoured, which is interesting from the perspective of its high degree of crystallinity of over 50 % [65] .…”

Preparation and Properties of Biodegradable Shape Memory Polylactic Acid/Poly(ε‐caprolactone) Blends under Volume Elongational Deformation

“…Detailed information about the ERM can be found in previous reports. [ 20 ] The inner mixing system of the ERM is composed of the eccentric rotor, left and right stator, and top cover, while the mixing chamber is airtight. According to the different functions, it can be divided into three sections, i.e., compression zone A, reflux zone B, and compression zone C. The eccentric rotor rotates accompanied by revolution.…”

Enhanced Electrochemical Performance of Hybrid Solid Polymer Electrolytes Encompassing Viologen for All-Solid-State Lithium Polymer Batteries

“…Generally, the incorporation of inert ceramic oxides as filler in a polymeric host reduces its crystallinity, facilitates the ionic conduction, and helps preserving the mechanical properties and shear modulus, fundamental to mitigate lithium dendrite formation. The most studied fillers have been nanometric oxides such as SiO 2 , , ZrO 2 , Al 2 O 3 , , and TiO 2 . Also, the ferroelectric BaTiO 3 was found to significantly enhance the ionic conductivity depending on the grain size and crystal structure .…”