Influence of Hydrothermally Synthesized Cubic-Structured BaTiO₃ Ceramic Fillers on Ionic Conductivity, Mechanical Integrity, and Thermal Behavior of P(VDF–HFP)/PVAc-Based Composite Solid Polymer Electrolytes for Lithium-Ion Batteries

Abstract

Solid polymer electrolytes (SPEs) with high ionic conductivity and wide electrochemical window are highly desirable for all-solid-state rechargeable lithium batteries. Herein, we report the use of hydrothermally derived nano-BaTiO3 (BT) as nanofillers in poly­(vinyl acetate)/poly­(vinylidene fluoride–hexafluoro propylene) and its use as composite SPE (CSPE) for Li-ion batteries. The CSPE was prepared by the solution casting technique and lithium bis-trifluoromethanesulfonylimide is used as salt. The molecular interaction among the various constituents and the surface morphology of the CSPEs were characterized by Fourier-transform infrared spectroscopy and field-emission scanning electron microscopy analysis respectively. BT (7.5 wt %) in CSPE was found to be the optimum composition to obtain a high ion conductivity of 2 × 10–3 S cm–1 at ambient temperature. The CSPE exhibits better mechanical strength (6.9 MPa), wider electrochemical window (5.4 V), and higher lithium transference number (0.48) than SPEs. Solid-state lithium cell was demonstrated as a proof of concept using lithium as an anode and LiFePO4 and SPE/CSPE (7.5 wt % BT) as cathode and electrolyte, respectively. The CSPE cell shows an enhanced specific discharge capacity of 132 mA h g–1 at 0.1 C, cycling performance up to 40 cycles, and 99% coulombic efficiency. The properties above well support the CSPE as a potential electrolyte-cum-separator for Li-ion batteries couple with high-voltage cathode material.

Recent progress on core-shell structured BaTiO3@polymer/fluorinated polymers nanocomposites for high energy storage: Synthesis, dielectric properties and applications

“…The addition of silver nanoparticles was found to enhance the mechanical properties of the polymer and also retarded crack propagation and fracture behavior, and thus improved the durability of the denture base. A similar strategy for the same application was also reported by Sasikumar et al [130] who prepared CSPE using BT, PVAc/poly(VDF-co-HFP) and lithium bistrifluoromethanesulfonylimide (LiTFSI) as the salt (Fig. 37).…”

“…Results show that compared with ceramic free SPE, the conductivity was increased to reach a value of 2 x 10 -3 Scm -1 at ambient temperature. Moreover, it was found that in the case of CSPE permission of [130] Copyright 2018 American Chemical Society.…”

“…Another promising field of use of polymer nanocomposite materials is energy storage applications[71,[129][130][131][132][133].Kumar et al [129] used nanocomposite materials consisting on BT nanoparticles and poly(VDF-co-HFP) polymer matrix to prepare a composite solid polymer electrolyte (CSPE) for Li-ion batteries. Since the ionic conductivity of the pure polymer poly(VDF-co-HFP) is not enough to be used as SPE, lithium triflate salt was added and the nanocomposites were synthesized by solution casting technique.…”

Flexible, high-voltage, ion-conducting composite membranes with 3D aramid nanofiber frameworks for stable all-solid-state lithium metal batteries

“…4a, b), suggesting that less triflate-containing anions were in pairs in the ANF-based electrolytes [68]. The intensity of the peak at around 1631 cm −1 with respect to the LiTFSI aggregation [67] also decreased greatly. On the basis of the elemental electronegativity values, FTIR analyses and reports from other researchers [62][63][64], we can easily deduce that the hydrogen bond interactions between the -NH groups in ANF and the TFSI − anions (mainly the F atoms, because of the high F electronegativity and the F-related peak intensity change) resulted in the effective dissolution and dissociation of LiTFSI, which would increase the free ion concentration (C i ).…”

Ανάπτυξη Ανοδικών Και Καθοδικών Νανοδομημένων Υλικών Για Εφαρμογή Σε Μπαταρίες Λιθίου

“…Η μπαταρία είναι μια διάταξη, η οποία μετατρέπει τη χημική ενέργεια σε ηλεκτρική μέσω μιας ηλεκτροχημικής οξειδοαναγωγικής αντίδρασης. Συγκεκριμένα, κατά τη φόρτιση, τα δύο ηλεκτρόδια συνδέονται με μια εξωτερική πηγή ηλεκτρικού ρεύματος και η ενέργεια που δίνεται στο σύστημα αποθηκεύεται στη μπαταρία με τη Παράλληλα, έχει μελετηθεί αρκετά η χρήση του συμπολυμερούς PVdF-HFP (88:12) ως πολυηλεκτρολύτη [190,191], ενώ μια πιο πρόσφατη μελέτη αναφέρει ότι το συμπολυμερές PVDF-HFP/PVA με BaTiO3 [192] παρουσιάζει ιοντική αγωγιμότητα 2 mS cm -1 . Κάποια άλλα συστήματα που έχουν μελετηθεί, περιλαμβάνουν ηλεκτρολύτες από γέλη πολυμερούς (gel polymer electrolytes, GPEs) που βασίζονται σε υβριδικές μεμβράνες με ιονικά υγρά με ιοντικές αγωγιμότητες πάνω από 6 mS cm -1 στους 30 ο C και καλή ηλεκτροχημική σταθερότητα σε δυναμικό πάνω από 5.0 V [193].…”