Lithium Ion Conducting Poly(ethylene oxide)-Based Solid Electrolytes Containing Active or Passive Ceramic Nanoparticles

Abstract

Polymer-based solid electrolytes containing ceramic nanoparticles are attractive alternatives to liquid electrolytes for high-energy density Li batteries. In this study, three different types of fillers have been dispersed in poly­(ethylene) oxide (PEO) polymer matrices, and the effects on the resulting ionic conductivity of the nanocomposites have been examined. In this respect, the efficacy of one active, liquid-feed flame spray pyrolysis synthesized amorphous Li1.3Al0.3Ti1.7(PO4)3 (LATP), and two passive filler materials, TiO2 and fumed silica nanoparticles, are compared. Nanocomposite electrolytes are prepared with up to 20 wt % particle loadings. PEO/LiClO4 with 10 wt % LATP nanoparticles exhibits an ionic conductivity of 1.70 × 10–4 S·cm–1 at 20 °C, the highest among the surveyed systems, despite exhibiting comparable or higher degrees of crystallinity and glass transition temperatures than the systems containing passive fillers. The ionic conductivity of the composites with LATP nanoparticles exceed that of the polymer matrix by 1 to 2 orders of magnitude. We attribute this remarkable enhancement to cation transport within the interphase region surrounding the particles, which achieves percolation at low nanoparticle loading. The development of this interphase structure is influenced by the active nature of the LATP filler, and we estimate the inherent conductivity of the interphase to be 3 to 4 times higher than the maximum measured value.

Rheology and Microscopic Heterogeneity of Poly(ethylene oxide) Solid Polymer Electrolytes

“…[20] Figure 3 presents the plot of G' and G" versus frequency of PEO 1 at Y S ¼ 0, 0.07, 0.10 and 0.15 measured at three different temperatures. The same trend was observed for PEO 4 which is not shown in Figure 3. The samples in solid (at T ¼ 30 C) and liquid (at T ¼ 80 C) states reveal distinct difference in viscoelastic properties.…”

“…In Figure 1(a), the DSC thermograms show a single T g value that increases gradually with a sharper transition as more LiClO 4 salt was added to PEO 1 (as well for PEO 4 which is not shown in Figure 1(a). The single T g value affirms the absence of microphase separation between PEO and salt at all salt concentrations.…”

“…Poly(ethylene oxide) (PEO)/lithium salt (Li) as a model for SPE system was chosen here as PEO is known to have high solvating power and the related system shows acceptable ionic conductivity. [4][5][6][7][8][9][10][11][12] In general, the glass transition temperature (T g ) of SPEs [11,[14][15][16] shows a gradual increase at low salt concentration where the polymer continuously solvates the cations generated from the addition of salt. Upon reaching solubility limit of polymer, T g value levels off.…”

Symmetric electric double‐layer capacitor containing imidazolium ionic liquid‐based solid polymer electrolyte: Effect of TiO2 and ZnO nanoparticles on electrochemical behavior

“…Inorganic fillers are also able to inhibit the crystallization of the polymer phases. Most of the fillers studied are passive fillers (non‐Li + conductive nanoparticles) instead of Li + conductive nanoparticles, which act as source of charge carriers or make extended migration pathways instead of contributing ionic conductivity to the electrolytes . The intrinsic dielectric constant of fillers plays role on ionic conduction in polymer electrolyte and controls capacitance of polymer electrolyte base double‐layer capacitor.…”

Core–Shell Hybrid Nanowires with Protein Enabling Fast Ion Conduction for High‐Performance Composite Polymer Electrolytes

“…Among various emerging energy storage devices, lithium‐ion batteries (LIBs) have been intensively investigated to satisfy the ever‐growing demands for cutting‐edge technologies of portable devices, large‐scale energy systems, electric vehicles, etc . For current LIBs, the expansive use of organic liquid electrolytes, however, poses potential hazards due to their volatility and flammability . In this regard, solid‐state electrolytes made of polymers or inorganic materials, which feature appropriate mechanical strength and safety to suppress dendrite growth, hold great promise in replacing the liquid electrolytes.…”