Solid Polymer Electrolyte Films Research Articles

Effect of succinonitrile on the structural, ion conductivity, and dielectric properties of PVDF‐HFP based solid polymer electrolytes

AbstractA detailed account of the poly(vinylidene difluoride‐co‐hexafluoropropylene) (PVDF‐HFP)/succinonitrile (SN)/lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) based solid polymer electrolytes (SPEs) of various compositions is reported. SN is incorporated as plasticizer, while LiTFSI is employed as the source of lithium ions. Fourier transfer infrared (FTIR) spectroscopy reveals the formation of polar and electroactive γ crystal phase by PVDF in pristine PVDF‐HFP and the prepared SPE films. FTIR further confirms the interaction between the host polymer and the salt and between the salt and the plasticizer. The interaction between the salt and plasticizer suggests that SN not only offers the plasticization effect but also facilitates salt dissociation. The ion conductivity increases with increasing salt content up to 20 wt% but beyond that concentration a decline in ion conductivity is observed, which could be attributed to the ion pair association or cluster formation due to the excess salt concentration that reduces the availability of free ions and ultimately leads to the reduction in ion conductivity. After including SN in the SPE formulation, electrochemical impedance spectroscopy reveals a substantial increase in room temperature ion conductivity of the SPE from ~1.08 × 10−5 S cm−1 for pristine SPE with 20 wt% salt to ~2.7 × 10−4 S cm−1 for plasticized SPE with 40 wt% SN and 20 wt% salt. This is attributed to the plasticizing effect of SN that enhances ion mobility through the matrix and to the increased charge carrier concentration (SN facilities salt dissociation). The fabricated SPEs exhibit a significant enhancement in ion conductivity with increasing temperature and the maximum ion conductivity of 1.1 × 10−3 S cm−1 is attained at 393 K by plasticized SPE with 40 wt% SN content. The ion conductivity of all the prepared SPEs follows the temperature dependent Arrhenius behavior, suggesting the thermally activated ion hopping mechanism of ionic conduction. Further, the plasticized SPEs display near unity ion transference number indicating the predominance of the ionic mode of conduction. The dielectric and electric modulus analysis reveal a faster relaxation phenomenon and hence higher ion conductivity of the prepared SPEs with increasing salt and plasticizer content.

Improving supercapacitor performance with novel potato starch-PVA solid polymer electrolyte blend modified by sodium perchlorate-glycerol additives

The synthesis and analysis of Solid Polymer Electrolytes (SPEs) derived from a blend of Potato Starch and Poly Vinyl Alcohol (PS-PVA), enhanced with Sodium perchlorate salt (NaClO4) and Glycerol (GCL) are explored in this work. Our focus is on their suitability for Electrical Double-Layer Capacitor (EDLC) devices. GCL, a non-toxic substance, served as the plasticizer, and sodium perchlorate was incorporated to enhance the ionic conductivity of the SPE film. The conductivity at room temperature for pure PS-PVA blend, in the absence of salt and GCL, was found to be 4.16 × 10−8 S cm−1. Upon adding an optimized quantity of NaClO4 salt, the conductivity increased to 1.02 × 10−5 S cm−1. Subsequent plasticization of the salt-polymer blend with GCL induced NaClO4 dissociation, further augmenting the conductivity by one order of magnitude. A conductivity value of 10.35 × 10−5 S cm−1 was achieved for the film with 30 wt% GCL. Morphological, electrical, and structural analyses revealed that synthesized polymer films exhibited favorable characteristics. The suitability of these electrolytes for Electric Double-Layer Capacitors (EDLC) was studied using electrochemical characterizations and cycling tests for 2000 cycles. The findings demonstrate their potential for use in energy storage devices, showcasing excellent performance in specific capacitance, energy, and power densities.

Tuning Electrochemical Performance of Polymer Electrolyte Films through Metal Oxide Incorporation

AbstractWith the escalating global energy demand, the exploration of alternative, easily accessible, and cost‐effective energy sources has become imperative. The diminishing reserves of conventional energy resources underscore the urgency to transition towards renewable energy. Solid polymer electrolytes (SPEs) have gained prominence for energy storage electrochemical devices due to their high flexibility and favorable electrode–electrolyte interactions. This study focuses on synthesizing nano cuprous oxide (CuO) semiconductors via the precipitation method. The prepared CuO nanofiller is homogeneously dispersed into a polymer electrolyte solution. Utilizing the solution cast method, free‐standing polymer electrolyte films are fabricated, exhibiting commendable mechanical stability. Polyvinyl alcohol (PVA) serves as the host material, with potassium iodide (KI) salt, forming the basis for the polymer electrolyte. The resultant electrolyte films underwent comprehensive characterization for their electrical and optical properties. The investigation aims to identify the optimal composition of the electrolyte film with superior conductivity. The selected composition will be employed in the fabrication of various electrochemical devices, demonstrating the potential for enhanced energy storage applications. This work not only contributes to the synthesis of advanced solid polymer electrolyte films but also paves the way for the development of efficient and sustainable energy storage solutions in the realm of renewable energy technologies.

Compositional dependence of electrochemical properties in biopolymer blend-based solid electrolytes doped with sodium perchlorate for EDLC applications

Biopolymer-based blends of solid electrolytes capable of conducting sodium ions were prepared via solution casting by incorporating sodium carboxymethyl cellulose (NaCMC) and polyvinyl alcohol (PVA) with varying concentrations of sodium perchlorate monohydrate (NaClO4.H2O), which was used as the dopant. The prepared electrolytes were characterized to reveal their structural, vibrational, electrical, and electrochemical properties that make them promising as solid polymer electrolytes (SPEs). X-ray diffraction (XRD) analysis showed that the amorphous nature of the sample increased with the addition of NaClO4.H2O salt concentrations of up to 30 wt.%. The complexation between the polymers and salt was confirmed by Fourier-Transform Infrared (FTIR) analysis. The SPE exhibited an optimal ionic conductivity of (1.90 ± 0.05) ×10−5 S cm−1, which is three orders higher than that of the pristine polymer blend with (5.31 ± 0.61) ×10−8 S cm−1, as determined by electrochemical impedance spectroscopy (EIS) analysis. Scaling studies conducted based on AC conductivity and tangent loss revealed that these measurements could be represented by a single master curve, which suggests that the optimal sample adheres to the time-temperature superposition principle (TTSP). The temperature dependence of Jonscher's exponent indicates that the conduction mechanism can be effectively represented by the Quantum Mechanical Tunneling model (QMT). Both transference number measurement (TNM) and linear sweep voltammetry (LSV) analyses validated the electrolyte's suitability for energy device applications by demonstrating its high ion transference number and electrochemical potential window of 3.93 V. The optimized SPE film was subsequently utilized in an electrochemical double-layer capacitor (EDLC) device to evaluate its performance as both an electrolyte and separator. The supercapacitor exhibited an impressive energy density of 15.18 Wh kg−1 and a power density of 4512.5 W kg−1, along with remarkable stability in terms of cycle life.

Structural, electrical, and transport properties of a PVB: NH4Br complexed solid polymer electrolyte films for electrochemical cell applications

ABSTRACT Polymer electrolytes are a key development in advancing battery technology, enabling more efficient energy storage. This study focused on developing a solid-state polymer electrolyte film by doping NH4Br with Polyvinyl Butyral (PVB) using a solution-cast method. X-ray diffraction (XRD) was employed to evaluate the amorphousness and crystallinity of the films, while Fourier Transform Infrared Spectroscopy (FTIR) confirmed complex formation between the salt and polymer. The glass transition temperature (Tg) of the electrolyte film was estimated using Differential Scanning Calorimetry (DSC). Ionic conductivity was measured through AC impedance spectroscopy, revealing that the PVB-NH4Br electrolyte doped with 30 wt% NH4Br at 30 °C had an ionic conductivity of 1.47 × 10−7 S cm−1. This conductivity followed an Arrhenius relationship, where conductivity increased with temperature. Dielectric studies showed that at low frequencies, the dielectric constant and loss were higher, while both decreased at higher frequencies. DC Wagner’s polarization technique verified that ion transport was the dominant conduction mechanism. Discharge testing of the electrolyte film using a Swagelok cell showed an open-circuit voltage (OCV) of 1.2 V and a short-circuit current (SCC) of 0.42 mA, indicating promising performance for battery applications.

Self-healing and recyclable polyurethane-based solid-state polymer electrolyte via Diels-Alder dynamic network

Compared with liquid electrolytes, solid-state polymer electrolytes (SPEs) with better thermal, mechanical stability and processablilty are urgently required for the development of next-generation flexible energy storage devices. Herein, a series of polyurethane-based solid polymer electrolytes (PUBXSPE) with cross-linking structure were prepared by Diels-Alder reaction. The hydrogen bonding between the urea groups and dynamic Diels-Alder reaction endows the solid polymer electrolyte with excellent self-healing ability without external stimuli at room temperature. The PUBXSPE also displays good liquid affinity and superior recyclable properties, which provide a practical idea for the design of multifunctional polymer electrolytes. Although the cross-linking solid polymer electrolytes films display unsatisfied ionic conductivity about 10−6 S cm−1 at 60°C, the ionic conductivity value of the self-healing and recycled PUB1SPE were close to their pristine one. The wide working voltage window of PUBXSPE (>5.0 V) indicate that they can meet the requirements of most cathode materials. Moreover, the Li|PUB1SPE|LiFePO4 maintained a good coulombic efficiency (> 98.0 %) throughout all the cycle at 60°C, and the flexible cells can successfully light the blue diode under harsh conditions. This work provides new insights and concepts to design flexible, reliable, and safe polymer electrolytes for electronic devices at high-temperature.

AC Impedance Analysis of Blend Polymer Electrolyte of PVP – PPA with Magnesium Salts as an Ionic Dopant for Potential Battery Applications

Abstract Solid polymer electrolyte films containing blend polymer electrolyte of Polyvinylpyrrolidone (PVP) and Poly p - amino benzoic acid (PPA) with varying ratios of magnesium salts were synthesized by solution casting method. Their conduction and relaxation mechanisms were studied by impedance spectroscopy (AC) at room temperature. The dependence of electrical data on frequency was analyzed by Cole – Cole plot and Jonscher’s power law. The semicircle seen in the plot represents the double relaxation process and shows how bulk electrolyte and the interfacial effect contribute to non-Debye and electrical conduction. The ac and dc conductivity values were calculated and the conductivity variation for the blend polymer PVP – PPA doped with different concentrations of magnesium salts was explained by the ionic contribution of the electrolytes. The dielectric constant and dielectric loss were measured by the dielectric investigations. The relaxation phenomenon of these electrolytes is provided by the dissipation factor analysis and electric modulus value. The conductivity of the system determines the suitability of the thin film concentration for potential battery applications as a polymer electrolyte.

Effect of Lithium Triflate (LiTf) Salt on the Properties of the Pectin-based Polymer Electrolytes Films

Currently, liquid electrolytes (LEs) that have been used in many electrochemical devices, face safety concerns due to leakage problems. Consequently, solid polymer electrolytes (SPE) consisting of a natural polymer host that is leak-proof, biodegradable, and flexible are widely studied. In the current study, the effect of various weight percentages (%) (i.e.: 10, 20, 30, 40, and 50 wt.%) of lithium triflate (LiTf) salt on the structural and electrochemical properties of pectin-based SPE films was investigated. The SPE films were prepared using the solvent casting technique. Solid, flexible, and self-supporting films of pectin-based SPE were successfully acquired by the addition of up to 50 wt.% of LiTf. As proven by FTIR analyses, there occur interactions between the lithium cation and the pectin coordinating sites (OH and C=O). These interactions minimized the formation of hydrogen bonding between pectin chains, hence explaining the formation of flexible films. Also, the polymer-salt interactions contributed to the improvement in the amorphous phase of the system. The minimized formation of hydrogen bonding, improvement in the amorphous phase, and the increased amount of charge carriers in the LiTf-doped pectin-based SPE had contributed to the increase in the ionic conductivity of the system with salt content. The highest conducting sample, P5 (50 wt.% LiTf) exhibited the ionic conductivity of 3.87 × 10-5 S cm-1 which was four orders of magnitude higher than pure pectin film of 2.24 × 10-9 S cm-1.

High-performance solid-state Li-ion batteries enabled by homogeneous, large-area ferroelectric PVDF-TrFE solid polymer electrolytes via horizontal centrifugal casting method

Solid polymer electrolytes (SPEs) have emerged as promising alternatives for enhancing the safety features of lithium-ion batteries (LIBs) while remaining compatible with established LIB manufacturing processes. However, a persistent challenge has been the relatively limited yield achieved via traditional fabrication techniques such as solution casting and doctor blade methods. In this study, we present a novel strategy to produce extensive and uniform films of solid polymer electrolytes using a ferroelectric polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) polymer. This approach employs horizontal centrifugal casting (HCC), a technique hitherto unutilized for SPE production. The substantial centrifugal forces generated during the HCC process yield SPE films characterized by uniform thickness across the surface and elevated ionic conductivity at ambient temperature. Compared to conventional solution casting techniques, the Li//Li cell featuring the SPE derived from HCC manifests stable electrochemical performance and increased cycle endurance. Additionally, a full cell incorporating a Li iron phosphate cathode displays consistent electrochemical behavior at room temperature. Notably, a 3 × 4 cm2 pouch cell maintains its performance attributes even under mechanical stress conditions such as folding and punching. These findings underscore the potential effectiveness of employing the HCC method in the development of high-performance SPE-based LIB systems.

To Study the Effect of Nanoparticle TiO2 on Sodium (Na+) – Ion Conducting Solid Polymer Electrolyte System: [80PEO:20NaPF6

AbstractTo study the effect of nanofiller particle TiO2 on sodium (Na+) – ion conducting solid polymer electrolyte (SPE) film: [80PEO:20NaPF6] and nanocomposite polymer electrolyte (NCPE): [80PEO:20NaPF6] + xTiO2, where x = 1–9 wt. (%) have been prepared. SPE film composition: [80PEO:20NaPF6] selects as Ist‐phase host and nano‐sized (<100 nm) filler materials TiO2 as IInd‐phase dispersoid. Both SPE and NCPE films have been prepared by the hot‐press technique. Filler particle‐dependent conductivity study reveals the NCPE system: [80PEO:20NaPF6] + 8TiO2 as the highest conducting composition with σrt − 3.53 × 10−6 S cm−1, which is approximately one order of magnitude higher than the SPE optimum conducting composition (OCC) (σrt) ≈ 7.78 × 10−7 S cm−1. Ion transport properties for both SPE and NCPE system have been evaluated in terms of ionic conductivity (σ) and total ionic (tion)/cationic (t+) transference numbers using combined AC/DC techniques in order to evaluate its usefulness in all‐solid‐state battery applications. Structural/thermal properties have been characterized using X‐ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques. A cyclic voltammetry (CV) study has been performed in SPE and NCPE OCC film to evaluate the electrochemical performance for battery application.

Poly(Vinylidene Fluoride‐CO‐Hexafluoropropylene) (PVDF‐HFP) Incorporated Acetylene Black: Electrical, Optical, and Structural Studies

AbstractThe primary goal of this study is to synthesize a high‐conducting polymer electrolyte film. The PVDF‐HFP and NaSCN film are prepared which showed the highest conductivity at 30 wt% dopant of NaSCN in the Polymer PVDF‐HFP which is 1.24× 10−4 S cm−1. Therefore, here the base polymer is taken as PVDF‐HFP and NaSCN (30 wt%) and further Acetylene Black is added to check the variation in the conductivity of the polymer film. Solution casting technique is used to create solid polymer electrolyte films using poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) with salt sodium thiocyanate and Acetylene Black. Polarized optical microscopy (POM) is used to evaluate the morphology of the polymer film surface. Fourier transform infrared spectroscopy (FTIR) to check the presence of functional group is used, impedance spectroscopy is used for the measurement of the conductivity of the sample, linear sweep voltammetry for finding electrical stability window, and transference number measurements for concentration of charge carriers are done for the electrical studies of polymeric films. The 1 wt% Acetylene Black doped polymer electrolyte film is found to have the maximum ionic conductivity, which is 1.95 × 10−3 S cm−1. The solid polymer electrolyte film has an electrochemical stability window (ESW) of 4.8 V and tion value of 0.83.

Xylose- and Nucleoside-Based Polymers via Thiol-ene Polymerization toward Sugar-Derived Solid Polymer Electrolytes.

A series of copolymers have been prepared via thiol-ene polymerization of bioderived α,ω-unsaturated diene monomers with dithiols toward application as solid polymer electrolytes (SPEs) for Li+-ion conduction. Amorphous polyesters and polyethers with low Tg's (-31 to -11 °C) were first prepared from xylose-based monomers (with varying lengths of fatty acid moiety) and 2,2'-(ethylenedioxy)diethanethiol (EDT). Cross-linking by incorporation of a trifunctional monomer also produced a series of SPEs with ionic conductivities up to 2.2 × 10-5 S cm-1 at 60 °C and electrochemical stability up to 5.08 V, a significant improvement over previous xylose-derived materials. Furthermore, a series of copolymers bearing nucleoside moieties were prepared to exploit the complementary base-pairing interaction of nucleobases. Flexible, transparent, and reprocessable SPE films were thus prepared with improved ionic conductivity (up to 1.5 × 10-4 S cm-1 at 60 °C), hydrolytic degradability, and potential self-healing capabilities.

The Effect of Sodium Acetate on Biodegradable Rice Starch-Based Solid Polymer Electrolyte for Supercapacitor

This study examined the use of sodium acetate salt as an ionic dopant in biodegradable solid polymer electrolyte (SPE). In the solution casting method for making polymer electrolyte, rice starch is used as the host polymer and glycerol is used as the plasticizer. The characteristics of SPE film were investigated using X-Ray Diffraction (XRD), Fourier Transform Infrared (FT-IR), and Thermogravimetric Analysis (TGA). Salt enhances the amorphous structure by decreasing the crystallinity of the polymer. Alternatively, it decreases the temperature of thermal breakdown. In addition, the biodegradability of SPE was investigated using the soil burial method. Electrochemical Impedance Spectroscopy (EIS) was used to evaluate the ionic conductivity behavior and temperature dependent of SPE. The 35% sodium acetate salt addition makes the supercapacitor's electrolyte have the highest ionic conductivity at room temperature, which is 5.57x10-4 S/cm.

MXene nanofiller doped ion conducting polyethylene oxide for electrochemical devices

AbstractNanofiller‐doped polymer electrolyte‐based electrochemical devices are now emerged as a novel material for electrochemical devices. This paper reports a solid polymer electrolyte film doped with a new nanofiller synthesized by the solution casting technique. Electrical, optical, and photoelectrochemical characterization are presented in detail. Electrochemical impedance spectroscopy (EIS) shows with the dispersion of nanofillers conductivity increases attains maxima and decreases. The maximum conductivity was at 0.04 wt% nanofiller concentration of 2.05 × 10−4 S/cm. The calculated ionic transference value was 0.92 which shows the dormancy of the system as ionic. The linear sweep voltammetry confirms a high electrochemical stability window (ESW) of 4.01V. Sandwitched electrical double‐layer capacitors (EDLC) have been developed using carbon‐based electrodes and sandwitched nanofiller dispersed polymer electrolyte, showing a high specific capacitance value of ~200 F/g.

Amorphous Magnesium-Doped Chitosan films as solid polymer electrolytes for energy storage device applications

Magnesium ion-conducting biodegradable solid polymer electrolyte (SPE) films of magnesium perchlorate [Mg(ClO4)2] doped Chitosan [CS] were prepared using the solution casting technique at room temperature. XRD study shows that amorphous nature of the polymer matrix increases upon doping. FTIR deconvolution confirm the complexation generated between the salt and the polymer. The current–voltage measurement exhibited electrochemical stability window for all samples above 2.14 V. The ionic transference number for the highest conducting sample was 0.99. The impedance analysis was done for each SPE film, and the sample with the highest concentration (40 wt%) exhibited the highest conductivity, 5.7 × 10-4 Scm−1. The prepared primary magnesium battery using the highest conducting SPE showed open circuit potential of 2.112 V. Due to its exceptional qualities, this prepared electrolyte may be a strong contender for energy storage systems.

(Invited) Electrolytes for Next-Generation Sodium Metal Batteries

Developing reliable and cost-effective electrical energy storage systems (EESs) for portable electronics, electric vehicles, and grid storage applications is vital. Na-ion batteries are the most promising alternative technology owing to their natural abundance and low sodium cost.[1] Solid-state batteries (SSBs) have garnered extensive attention for their ability to suppress the safety hazards of organic liquid electrolytes by replacing them with solid electrolytes.[2] Among the various solid electrolytes being explored, our group mainly focuses on NASICON (Sodium superionic conductor) type silicate and solid polymer electrolytes. Sodium silicates are a class of materials with composition, NaxMxSixOx (M = rare-earth metals, x = integer (1-10)).[3] They have the advantage of low sintering temperature (~1050 °C) and 3D framework structure containing MO6 octahedra and SiO4 tetrahedra providing facile ionic movement.[4] Solid polymer electrolytes (SPE) are known for their flexibility and electrode compatibility. Highly conductive, filler-free composite solid polymer electrolyte films were prepared using poly(vinylidene fluoride), poly(vinyl pyrrolidone) (PVP), and NaPF6.[5] PVP binder played an essential role in improving Na ion conductivity and excellent plating−stripping performance. This talk will present an overview of these solid electrolytes for next-generation sodium metal batteries.

(Best Poster Award - 1st Place) Characterisation of the Li Metal|Electrolyte Interface of PEO-Based SPEs with Borate Salts, Using in Situ Li Deposition PES Measurements Aided by AIMD Simulations

Lithium metal and anode-free batteries has the potential to increase the energy density and specific energy of the batteries drastically. However, when regular electrolyte materials are tried for these concepts they are plagued with problems due to degradation of the electrolyte at the interface and processes like dendrite formation which leads to poor capacity retention.[1] A strategy to mitigate these problems is to use Solid Polymer Electrolytes (SPEs), as these have better stability towards lithium metal. In order to find appropriate chemistries to use in SPE-based cells it is important to investigate and understand their anode interface, as this is where the Solid Electrolyte Interphase (SEI) is created from the degradation products during cycling.This work investigates three polyethylene oxide (PEO)-based SPEs, using lithium tetrafluoroborate (LiBF4), lithium bis(oxalate)borate (LiBOB), and lithium difluoro(oxalate)borate (LiDFOB) as the lithium conducting salts. The interfaces of these SPEs (PEO:LiBF4, PEO:LiBOB, and PEO:LiDFOB) was studied using Photo-Electron Spectroscopy (PES) with in situ lithium deposition, where lithium atoms are evaporated on top of the SPE film. The analysis of the core-level spectra before and after lithium deposition is compared to Ab Initio Molecular Dynamics (AIMD) simulations of the interface, where lithium atoms are gradually added during the simulation. These experimental and theoretical methods are meant to mimic the electrochemical plating of lithium at the lithium|SPE interface during charging of a lithium metal or anode-less cell.The interfaces of PEO:LiBOB and PEO:LiBF4 show, among other compounds, polyethylene as a breakdown product at the interface. PEO:LiDFOB shows a much lesser degree of degradation compared to the other two systems. The degradation layer is however still effective at protecting the SPE from further breakdown, as PEO:LiDFOB has a relatively high capacity retention compared to PEO:LiBF4 and PEO:LiBOB. Suggested is that the LiF provides a better electrochemical stability, while the boron and oxalate breakdown products provides a higher mechanical stability at the interface.[1] Huang WZ, Zhao CZ, Wu P, Yuan H, Feng WE, Liu ZY, Lu Y, Sun S, Fu ZH, Hu JK, Yang SJ. Anode‐Free Solid‐State Lithium Batteries: A Review. Advanced Energy Materials. 2022 Jul;12(26):2201044. Figure 1

Effect of Sodium Iodide on Structural, Electrical and Optical Properties of Polyethylene Oxide/ Carboxymethyl Cellulose Blends

The production of highly potential Solid Polymer Electrolyte (SPE) materials has been the subject of extensive research. Due to their high flexibility, superior processability and enhanced resistance to electrodes during the charging/discharging process, they found to exhibit wide applications when compared to liquid or gel. In the present study, SPE films with 30/70 composition of Polyethylene oxide/Carboxymethyl cellulose blend, doped with Sodium Iodide (NaI) were prepared using a simple solution cast technique. The optical properties of the prepared samples were studied by UV–Vis spectroscopy technique and the results show that, the energy band gap decreases with the increase of salt concentration which is due to the enhancement of amorphous nature with the concentration of salt and is as evidenced from X-Ray diffraction studies. The electrical properties of the samples were studied using impedance analyser. The dielectric constant of the prepared samples decreases exponentially with frequency of applied electric field. In addition, the AC conductivity of the blend was found to increase with increase in salt concentration and the maximum conductivity was observed for 0.03% NaI salt doped Polyethylene oxide/Carboxymethyl cellulose blend. Thus, the said samples can be used in the preparation of SPE’s

Investigation of the electrochemical performance of Mg-ion batteries based on PVDF-HFP thin polymer electrolyte films

In the present work, poly(vinylidene fluoride-hexafluoropropylene):magnesium trifluoromethanesulfonate (PVDF-HFP:MgTf) polymer electrolytic films with a porous structure were developed using the solution-casting method. With its high performance and versatility, PVDF-HFP has been widely employed in the development of solid polymer electrolyte films (SPEFs). In this study, metal salt particles are successfully included as an inorganic filler into solid PVDF-HFP films, reducing pore size and boosting the amorphous character of the films. Fourier transform infrared spectroscopy is used to examine the chemical structure of the produced SPEFs, and scanning electron microscopy is used to evaluate the surface morphology and locate pores in the SPEFs. The surface nature of the PVDF-HFP films and the PVDF-HFP:MgTf is confirmed by X-ray diffraction. The electrochemical stability of PVDF-HFP and PVDF-HFP:MgTf films is studied through a differential scanning calorimetry experiment. Results revealed that PVDF-HFP:MgT films could be stabilized when filled with electrolytes and electrodes and made less porous by adding inorganic salt particles. Further, electrochemical impedance spectroscopy is used to measure electrical conductivity between 303 and 423 K. At room temperature, PVDF-HFP and PVDF-HFP/Mg2+ SPEFs have optimal ionic conductivities of 3.38 × 10−7 and 1.08 × 10−6 SS ccmm−1−1 respectively. Ionic conductivity was found to increase with temperature. The modulus of the imaginary part of the loss tangent (M′ and M″) was found to be related to dielectric and conductivity relaxation.

Correlations between the dopant concentration and ion transport properties of plasticized NaCMC-Pectin polyblend electrolyte membranes for electrochemical device applications

This study explores the structural and electrical properties of sodium carboxymethyl cellulose (NaCMC)–pectin (PC)–glycerol–NH4Br electrolyte films and investigates their potential applications in proton batteries. Plasticized solid polymer electrolyte (SPEs) films were fabricated using the solution casting method. The interaction between the salt and polymer blends was verified using Fourier-transform infrared (FTIR) analysis. Incorporation of various salt concentrations (up to 25 wt%) was found to enhance the amorphous phase of the polymer blend, as evidenced by X-ray diffraction (XRD) results. Additionally, the decrease in the glass transition temperature, as confirmed by DSC analysis, indicates that the inclusion of both plasticizer and salt contributed to this effect. An electrolyte with 25% wt. of NH4Br has the highest room temperature conductivity of 4.68 ×10−4 S cm−1. This electrolyte was employed to fabricate the proton battery for energy storage application.