Solid Polymer Electrolyte Films Research Articles

Synthesis and ion conduction mechanism of a new sodium ion conducting solid polymer electrolytes

Synthesis and ion conduction studies of a new Na+ ion conducting Solid Polymer Electrolytes (SPEs): (1-x) PEO: x NaCl, where 0 ≤ x ≤ 50 wt% have been reported. SPE films have been casted by a novel hot- press/dry technique in place of traditional solution cast method. The conductivity measurements as a function of salt complexation revealed SPE film: [70PEO:30NaCl] as the Optimum Conducting Composition (OCC) with σ ∼ 4.5 × 10-6 S/cm at 27 °C. A conductivity enhancement of approximately three orders of magnitude from that of pure polymeric host has been resulted in SPE OCC due to salt complexation in PEO. Ion conduction mechanism have been explained with the help of some basic ionic parameters viz. ionic conductivity (σ), ionic mobility (μ), mobile ion concentration (n), ionic transference number (tion) and various theoretical models proposed for polymeric electrolyte materials. The temperature dependent conductivity studies have also been done to compute the activation energy (Ea) values from ‘log σ-1/T’ Arrhenius plots.

Microstructural, dielectric, and transport properties of proton-conducting solid polymer electrolyte for battery applications

Poly (vinyl alcohol) (PVA) complexed with ammonium chloride (NH4Cl) solid polymer electrolyte films was prepared using solution casting technique. Complexation of dopant with polymer was studied using Fourier transform infrared spectroscopy (FTIR). X-ray diffraction (XRD) results reflect that degree of crystallinity of the polymer increases with doping level. Surface morphology and topology of the electrolyte were studied using Scanning electron microscopy (SEM) and atomic force microscopy (AFM). Thermogravimetric analysis (TGA) results accounts for the increase of thermal stability of PVA due to the incorporation of NH4Cl. Impedance analysis was carried out to understand relaxation phenomena of polymer electrolyte. Dielectric studies revealed that the mobility of charge carriers follows non-Debye nature of ionic relaxation. Electrical studies reveal that proton conduction occurs in this polymer electrolyte through Grotthus mechanism and maximum conductivity of the polymer electrolyte (7.5 wt% NH4Cl/PVA) has been observed to be 1.81 × 10−3 S/cm at 353 K. Transport parameters have been determined using Wagner’s polarization technique. The observed highest conductivity of polymer electrolyte indicates utilizing this electrolyte for the fabrication of proton battery applications, and accordingly, the cell parameters have been measured.

Synergistic effects of salt concentration and polymer blend composition on the crystal phases, dielectric relaxation, and ion conduction in PVDF/PEO/LiCF3SO3 solid polymer electrolytes

Effects of lithium triflate (LiCF3SO3) salt concentration and compositional weight ratio of poly(vinylidene fluoride) (PVDF)/poly(ethylene oxide) (PEO) blend host matrix on the structural, dielectric relaxation, and ion transport properties of PVDF/PEO/LiCF3SO3 solid polymer electrolyte (SPE) films have been investigated. Variations in the amounts of constituents in these SPEs enormously alter the characteristic crystal phases of polymers and their chain segmental dynamics. Ionic conductivity increases by more than five orders of magnitude on loading LiCF3SO3 amount up to 30 wt% in the 75PVDF/25PEO blend matrix, and by about two orders with the increase of PEO amount from 25 to 90 wt% in the polymer blend host matrix of PVDF/PEO–25 wt% LiCF3SO3 films. Correlation between ionic conductivity and relaxation time confirms that the transport of ions is coupled to the polymer chain segmental motions in these SPEs. Total ion transference number, electrochemical voltage stability, and cyclic performance of these electrolyte materials are determined and appropriately explained.

Dielectric relaxation, Li-ion transport, electrochemical, and structural behaviour of PEO/PVDF/LiClO4/TiO2/PC-based plasticized nanocomposite solid polymer electrolyte films

Abstract Poly(ethylene oxide) (PEO)/poly(vinylidene fluoride) (PVDF) (75/25 wt/wt%) host polymer blend matrix, lithium perchlorate (LiClO4) ionic dopant (25 wt%), titanium dioxide (TiO2) inorganic nanofiller (10 wt%), and propylene carbonate (PC) plasticizer (10–30 wt%) based different compositions electrolyte films were prepared. The morphological study reveals that the spherulite and fibril-like microstructures of the 75PEO/25PVDF–25 wt% LiClO4 primary electrolyte film turned highly complex having cracks, pores, and some crumpled fluffier structures when TiO2 and PC were added. X-ray diffractograms of these films confirm their semicrystalline structures having α-, β-, and γ-phase crystals of PVDF, and also the characteristic crystallites of PEO and TiO2 nanoparticles. Complex dielectric permittivity, dielectric loss tangent, ac electrical conductivity, impedance, and electric modulus spectra over the frequency range 20 Hz–1 MHz at 27 °C were reported and analyzed for confirmation of various polarization processes and relaxations in these heterogeneous electrolyte materials. It is found that the dc ionic conductivity of these materials is principally ruled by the ions coupled chain segmental dynamics which promotes the cations hopping mechanism. The results confirm that the electrolyte films containing 10 wt% TiO2 along with PC ≥ 20 wt% have dc ionic conductivity more than two times higher as compared to that of the primary electrolyte film. All these electrolyte films have considerable electrochemical performance and nearly unity value of total ion transference number. The fascinating ionic conduction and electrochemical properties confirm these flexible-type electrolytes as appealing materials for advances in all-solid-state lithium ion conducting devices.

Dielectric Modulus and Conductivity Scaling Approach to the Analysis of Ion Transport in Solid Polymer Electrolytes

Solid polymer electrolyte films (SPEs) based on poly(methyl methacrylate) are prepared using a solution cast technique. The temperature‐dependent behavior of dielectric, modulus spectra and ac conductivity has been investigated. The long tail of the real part of modulus (M′) in the low frequency indicates the capacitive nature of the samples. The frequency dependence of imaginary part of modulus (M″) shows a non‐Debye relaxation that has been explained using the Kohlrausch–Williams–Watts stretched exponential function. The activation energy for the relaxation is almost same as the activation energy for the conduction. The relaxation time obtained from the tangent loss graph (τδ) is about two orders of magnitude larger than that obtained from the imaginary part of modulus graph (τm). The ac conductivity has been found to obey Jonscher's universal power law. Transport parameters show that addition of filler creates additional hopping sites for the charge carriers and also increases the charge carrier density. It is also observed that the higher ionic conductivity at higher temperature is due to increased thermally activated hopping rates accompanied by a significant increase in carrier concentration. The contribution of carrier concentration to the total conductivity is also confirmed from Summerfield scaling. POLYM. ENG. SCI., 60: 297–305, 2019. © 2019 Society of Plastics Engineers

AC conductivity studies of polyethylene oxide-garnet-type Li7La3Zr2O12 hybrid composite solid polymer electrolyte films

We have investigated both AC dielectric permittivity and ionic conductivity of hybrid composite solid polymer electrolyte (CSPE) films (~100 μm) comprised of sub-micron sized aluminum substituted cubic Li7La3Zr2O12 (LLZO) particles dispersed in polyethylene oxide-LiClO4 (PEO-LiClO4) matrix with [EO]:[Li] = 15:1. Homogeneous CSPE films with 50 wt% LLZO (PEO-LLZO-LiClO4) exhibit good flexibility and mechanical robustness up to 120 °C. The electrochemical potential stability window measured for these films was ~5.2 V vs. Li+/Li. The complex AC permittivity and conductivity were determined using the measured electrical impedance spectra in the range of 1 Hz to 300 kHz and found to be heavily affected by the electrode polarization in low frequency region. We have analyzed the data using an expression for complex AC conductivity that generalizes the power-law dependence taking into account the effect of electrode polarization and involving ionic and polymer segmental relaxation times in its description. This expression describes very well the observed behavior of AC dielectric permittivity and conductivity in the entire measured frequency region. The ionic and segmental relaxation times obtained from fitting the experimental data indicate a strong coupling between the ionic motion and segmental dynamics. Further, the observed temperature dependent conductivity follows the Vogel-Tammann-Fulcher (VTF) behavior implying a close correlation between ionic conductivity and segmental relaxation in these polymer electrolytes. The VTF model yields an activation energy of 0.32 eV for PEO-LiClO4 film, and 0.07 eV for PEO-LLZO-LiClO4 composite film, consistent with the observed enhancement in conductivity by two orders of magnitude at 30 °C upon the addition of LLZO particles.

Electrical and mechanical property of the polyvinyl alcohol based solid electrolyte film contains alum

The solid polymer electrolyte film is prepared using polyvinyl alcohol and alum by the reactive blending method. Different wt% of alum is used for the preparation of the films. Temperature dependent properties of the films were characterized by IR, A/C conductivity, dielectric, conductance, DSC and TGA. The X-ray diffraction pattern of the synthesized film showed an increased crystallinity over pure PVA. The constituent present in the polymer film is found out by EDX measurement. The spin state in which metals present in the film is found out by XPS analysis. The thermal stability of the film is increased over pure PVA. The tensile curve of the polymer sample contains 0.15 wt% of alum showed a strain induced crystallisation behavior due to plasticizing effect of the embedded salt. The polymer sample contains 0.15 wt% of alum showed conductivity (AC) of 1.73 × 10−4 S cm−1. Conduction pattern is studied by dielectric loss experiments.

Selection of best composition of Na+ ion conducting PEO-PEI blend solid polymer electrolyte based on structural, electrical, and dielectric spectroscopic analysis

In this paper, we report the investigation on structural, electrical, dielectric properties, and ion dynamics of novel blend polymer electrolyte matrix (PEO-PEI) complexed with sodium hexafluorophosphate salt. All the solid polymer electrolyte films have been synthesized via solution cast method. The SPE films were characterized by the X-ray diffraction, field emission scanning electron microscope, impedance-dielectric spectroscopy, and thermogravimetric analysis. The morphology of the SPE alters with salt addition and confirms the blend polymer complex formation. The FTIR analysis evidenced the complex formation, and increase in the fraction of free ions is achieved. The ionic conductivity exhibits a maximum at the stoichiometric ratio O/Na = 10 and follows the Arrhenius behavior. The fraction of free ions is maximum for the SPE film with the highest ionic conductivity. The optimum electrolyte possesses a voltage stability window of about 4 V, excellent thermal stability up to 380 °C, and high ionic transference number (~ 1). The complex permittivity and conductivity have been simulated in whole frequency window to extract relaxation time and dielectric strength. The dielectric constant and relaxation time exhibited sequentially a maximum and minimum for the SPE film with the highest ionic conductivity. The loss tangent peak shifts toward high frequency with addition of salt, and it infers the faster ion dynamics in the polymer matrix. Then the ion transport parameters number density of charge carriers (n), ion mobility (μ), and diffusion coefficient (D) have been obtained by three methods (FTIR, impedance spectroscopy, and loss tangent method) and are in absolute correlation with the impedance results. An ion transport mechanism has been proposed based on experimental findings.

Effect of Al2O3 on structural and dielectric properties of PVP-CH3COONa based solid polymer electrolyte films for energy storage devices

Nanocomposite polymer (NCP) films were prepared by doping sodium acetate (CH3COONa) in polymer of polyvinyl pyrrolidone (PVP) by complete dispersion of aluminum oxide (Al2O3) with different wt% proportions using solution cast method. The acquired NCP films were systematically characterized. The crystalline structure of the prepared NCP films was confirmed by XRD. The little agglomeration and grain sizes involved in the films were analyzed by SEM. The chemical bond formation and interchange reaction between the host, dopant salt and the nanofiller were confirmed by FTIR and Raman. The lowest energy bandgap values were observed to be 3.0 eV for the synthesized film with wt% ratio of PVP + CH3COONa:Al2O3 (80:20:1%). The highest ionic conductivity was found to be 1.05 × 10−3 S/cm for the prepared film with wt% ratio of PVP + CH3COONa:Al2O3 (80:20:1%). From the charge discharge characteristics it was concluded that the film with wt% ratio of PVP + CH3COONa:Al2O3 (80:20:1%) possesses long durability when compared to the other prepared films.

Lithium ion conduction in PVA-based polymer electrolyte system modified with combination of nanofillers

Nanocomposite solid polymer electrolyte films based on poly-vinyl alcohol were synthesized using solution cast technique. The effects of electric field on the ionic conductivity were investigated. The addition of nanofillers such as BaTiO3, SrTiO3, Al2O3, and MMT to PVA has been found to increase the DC electrical conductivity of the SPE films. The structural change induced in the sample due to the addition of nanofillers was investigated using DSC and XRD techniques. The XRD and DSC results show that amorphosity of the sample increased as the combination of nanofillers was added to the polymer matrix. The temperature dependence of the DC electrical conductivity was carried out between 298–323 K and varying the electric fields from 0 to 100 Vcm−1. The obtained results reveal that ionic conductivity of the electrolyte film increased non-linearly with electric field. The electric field and temperature-dependent conductivity of the polymer electrolyte films were explained using the mathematical model proposed earlier. The field factor and activation energy for the PVA-based system were evaluated.

Significant roles of the polymer matrix in the resistive switching behavior of polymer-based atomic switches

The impacts of the polymer matrix material on the resistive switching of solid polymer electrolyte (SPE)-based atomic switches are investigated. The switches consist of a spin-coated SPE film using silver salt incorporated polyethylene oxide, polyvinyl alcohol, or polyvinyl pirrolidone, which is sandwiched between Ag and Pt electrodes. The switching characteristics depend strongly on the structural, thermal, and transport properties of the polymer matrix, such as its crystallinity, glass transition temperature, and ionic conductivity. The temperature behavior of resistive switching can be explained by competition between increased segmental mobility and water evaporation in the polymer matrix. It is found that crystalline and semi-crystalline polymer electrolytes are likely to perform better than amorphous polymer electrolytes in realizing stable switching characteristics. These findings will contribute to the understanding and control of the device performance of SPE-based atomic switches.

In situ strain dependent electrochemical characterization of a stretchable-sliding battery

Stretchable batteries are needed to accommodate deformable geometries in tantalizing applications such as smart textiles, biomedical implants, and stretchable electronics. An increasing number of studies have focused on flexible and bendable batteries, but very few have investigated a stretchable lithium ion battery in which some or all components, including the electrodes, electrolyte, and encapsulation may be stretched. Here, we report the design, fabrication and characterization of a stretchable-sliding battery where the electrodes can slide, and the solid polymer electrolyte is stretched. The battery consists of a single solid polymer electrolyte film sandwiched between two sliding layered electrodes on each side. The two cathode layers are based on LiFePO4 active material, and the two anode layers are graphite based. The stretchable polymer electrolyte is composed of a specific blend of polyethylene oxide (PEO) of 100k and 600k molecular weights to enhance both the ionic conductivity and mechanical properties. Results show that the capacity of the stretchable-sliding battery increases at small tensile strains, but can degrade at larger strains. Tensile stress-strain curves of the stretchable battery and its components until failure are also presented. In situ strain-dependent electrochemical measurements provide critical insights on the stretching and sliding mechanisms in the battery. This study further validates the dual-functionality of the PEO solid electrolyte as both a stretchable film and a lithium ion conductor in a charged/discharged battery. This stretchable-sliding battery configuration can offer an experimental platform for in situ characterizations of solid polymer electrolyte films subjected to stretching inside an active electrochemical cell.

An Interaction of Chloro Substituted Alkoxy Thiourea as Dopant in Carboxymethyl Cellulose (CMC) for Solid Polymer Electrolyte

Alkoxy substituted aryl-thiourea derivatives provide excellent electronic properties due to the present of rigid π-systems within their molecular framework. This study introduces new thiourea derivative with general formula A-ArC(O)NHC(S)NHAr-D which was successfully synthesized with A is noted as aryl group containing chloro (-Cl) substituent ( 1A ), in which acts as electron acceptor, while D represented as –OC n H 2n+1 , the alkoxy chain tail acts as electron donor. Due to its characteristic of D-π-A system, alkoxy thiourea derivatives are applied as dopant in Carboxymethyl Cellulose (CMC) host material in order to form a conductive biopolymer solid polymer electrolyte (SPE) film. The formation of biopolymer-thiourea complex ( 1A-CMC ) has been analyzed through Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD) to determine the interaction between CMC and thiourea derivative in the form of film as well as Electrical Impedance Spectroscopy (EIS) for their ionic conductivity behavior. The highest conductivity at ambient temperature (303K) exhibits 1.44 x 10 -7 S cm -1 for CMC-thiourea complexation featuring chloro substitution ( 1A ). Indeed, biopolymer electrolyte materials featuring thiourea derivative as dopant has great potential to be developed as electrical conductor. Due to these findings, these so-called molecular wires candidate has opened wide possibilities to be applied in many micro-electronic devices in the near future.

The Effect of Carboxymethyl Cellulose as Bio Filler on Ionic Conductivity and Physical Property of Waste Cooking Oil Based Polyurethane Composite Polymer Electrolyte

Waste cooking oil (WCO) is an under-utilized, highly abundant raw material from food industry. In this study, WCO was used to prepare solid polymer electrolyte (SPE) films via solvent-free method. WCO was first pretreated and converted into polyol using epoxidation and hydroxylation reaction. Then, WCO-based polyol was combined with diisocyanate, LiCF3SO3 and carboxymethyl cellulose (CMC) to obtain polyurethane SPE films. CMC was added to SPE as bio-filler to observe the effect on ionic conductivity and mechanical properties of SPE. SPE films were characterized using Fourier transformed infrared spectroscopy, electrochemical impedance spectroscopy, x-ray diffraction spectrometer (XRD), differential scanning calorimetry and tensile strength. Addition of CMC resulted in increase of ionic conductivity up to 1.19 x 10-5 S/cm for 15% CMC. The ionic conductivity supported with reduced crystalline peaks intensity in XRD to show that the amorphous nature of SPE increased as more CMC added. Tensile strength also increased with addition of CMC and peaked at 10% CMC (34.17 MPa) due to effective hydrogen bond interaction between CMC and PU or salt. However, increased CMC amount further to 15% reduced tensile strength due to agglomeration of CMC particles. As a conclusion, addition of CMC is a viable method to improve both ionic conductivity and mechanical property of SPE.

Probing the dielectric relaxation processes and their correlation with ions transportation in the complexes of plasticized nanocomposite solid polymer electrolyte

Plasticized nanocomposite solid polymer electrolyte (PNSPE) film consisted of poly(ethylene oxide) and poly(methyl methacrylate) blend as host matrix, lithium perchlorate salt as ions dopant, ethylene carbonate as plasticizer, and montmorillonite clay nanoplatelets as inorganic nanofiller has been prepared by solution cast followed by the melt pressing. X-ray diffraction study of the PNSPE film confirms its amorphous structure with the existence of exfoliated nanoplatelets of the nanofiller. Dielectric and electrical dispersion of the film has been characterized systematically by employing the dielectric relaxation spectroscopy in the frequency range 2 × 101 to 1 × 106 Hz, at different temperatures. The relaxation times attributed to the various processes of structural dynamics of the PNSPE film have been probed by considering the individual spectrum of all the dielectric and electrical functions which are further validated by their master plot representation. The relaxation times corresponding to the dynamics of the electric double layers, electrode polarization, and interfacial polarization-affected polymer chain segments, cations coordinated polymers chain segments, and also the ionic conductivity in the ion–dipolar–nanofiller coordinated structures of the film have been determined. A generalized behaviour of these relaxation processes for probing the dynamical structures in all the solid polymer electrolytes has been demonstrated. It is further explored that these relaxation times of the PNSPE film exhibit a correlation with the dc ionic conductivity, and their temperature-dependent variation obeys the Arrhenius behaviour of nearly the same relaxation activation energies which are also found in good agreement with the conductivity activation energy.

Transport and Diffusion Properties in PEO-BaCl2 Polymer Electrolytes for Battery Applications

Barium chloride (BaCl2) doped polyethylene oxide (PEO) based solid polymer electrolyte (SPE) films are prepared using solution cast technique. Impedance analysis reveals that the ionic conductivity of pure PEO polymer enhances with frequency as well as BaCh concentrations, the maximum ac - ionic conductivity (1.09 × 10−4 Scm1) is observed at 10 wt% BaCl2 doped PEO polymer electrolyte films at high frequency. The temperature dependent conductivity studies were carried out for 10 wt% of BaCl2 concentration, here the maximum dc - ionic conductivity achieved is 1.44 × 10−2 Scm−1 at 333K temperature. From transport properties, it is observed that the transference number of ions in the polymer electrolyte system is 0.98 and electronic transference number are 0.019. Hence ions are the majority charge carriers than the electrons in BaCl2 doped PEO based solid polymer electrolytes. Diffusion coefficient study confirms the cations play a major role for the conduction mechanism with in the electrolyte system.

Dielectric relaxations and transport properties parameter analysis of novel blended solid polymer electrolyte for sodium-ion rechargeable batteries

A novel blended solid polymer electrolyte comprising polyethylene oxide and polyvinylpyrrolidone polymers for blending and sodium nitrate (NaNO3) as ion conducting species has been optimized via standard solution-cast technique. XRD, FESEM, and FTIR were performed to obtain the information about the structural changes, morphology, and microstructural changes (polymer–ion and ion–ion interactions) of the solid polymer electrolyte films. The electrochemical impedance spectroscopy, linear sweep voltammetry, and i–t characteristics were performed to evaluate the ionic conductivity, voltage stability window, and ion transference number. The impedance study was done in a broad temperature range (40–100 °C). The DSC and TGA were used to obtain information about the thermal transitions and thermal stability of prepared films. The ion dynamics is further investigated by analyzing the complex permittivity, loss tangent, and complex conductivity. All the plots were fitted through established theoretical model/expressions in whole frequency window to obtain dielectric strength, ion conduction path behavior, and relaxation time. Transport parameters such as number density (n), mobility (μ), and diffusion coefficient (D) of mobile ions were obtained by three methods and compared satisfactorily. Lastly, a coherent mechanism for the migration of charge transport carriers within the solid polymer composites has been proposed based on the performed experimental outcome.

Novel solid polymer electrolyte based on PMMA:CH3COOLi effect of salt concentration on optical and conductivity studies

Novel solid polymer electrolyte (SPE) films based on poly(methyl methacrylate) (PMMA) and lithium acetate (CH3COOLi) with different weight ratios of PMMA:CH3COOLi wt% (60:40, 70:30, 80:20 wt%) were prepared by solution casting technique. XRD analysis confirmed the amorphous nature of Li–PMMA SPE films. FTIR analysis revealed the structural changes in polymer by complexation with Li salt. From the optical absorbance studies, the value of lowest energy band gap was found to be 3.06 eV for the composition, PMMA:CH3COOLi (60:40 wt%). From AC impedance studies, the highest value of ionic conductivity 8.21 × 10−5 S/cm at 303 K for the SPE film PMMA:CH3COOLi (60:40 wt%) is observed compared to the reported literature. From the results of Li–PMMA SPE film with high ionic conductivity, it is a promising material for the application of solid-state battery.

Electrochemically Controlled Deposition of Ultrathin Polymer Electrolyte on Complex Microbattery Electrode Architectures

Solid state microbatteries are highly sought after for emerging microsensor technologies. To overcome the problem of the dwarfing capacity resulting from the miniaturization of the battery, 3D-structured platform consisting of high surface area micropillar-shaped electrodes are used. However, applying a conformal and continuous solid polymer electrolyte films onto the intricate 3D electrodes is a crucial step toward achieving functional microbatteries. In this work, we present our approach for the development of polyethylene oxide (PEO)-acrylate based ion conducting polymer thin films which function as solid polymer electrolyte (SPE) and a separator. The SPEs were electrochemically deposited on the 3D electrodes resulting in ultrathin, continuous, conformal, and pinhole-free polymer films. The electrochemical and Li+ ions transport properties of the SPEs were characterized by EIS measurements and cyclic voltammetry. Furthermore, the homogenous composition of the SPEs at various depths were confirmed by XPS depth profiling techniques.

Impact of shape (nanofiller vs. nanorod) of TiO2 nanoparticle on free‐standing solid polymeric separator for energy storage/conversion devices

ABSTRACTWe report the investigation on examining the impact of nanofiller (NF)‐ versus nanorod (NR)‐shaped titanium oxide (TiO2) nanoparticle on the structural, electrochemical, transport, thermal, and dielectric properties of the solid polymer electrolyte (SPE). Thin SPE films comprising of poly(ethylene oxide), sodium hexafluorophosphate, and dispersed with TiO2 NF, TiO2 NR (synthesized by hydrothermal route) has been prepared via solution cast technique. The shape of nanoparticle influences the morphological and structural properties as observed in field emission scanning electron microscope and X‐ray diffraction analysis. The highest ionic conductivity was exhibited by the NR dispersed system and is higher than NF dispersed system for all recorded concentration consistently. It is attributed to the formation of the long‐range conductive path with NR when compared with NF. In addition, the electrochemical stability window is much higher (~5 V) than the NF‐doped system. Furthermore, the dielectric properties of SPE were investigated and fitted in the complete frequency window (1 Hz–1 MHz; T = 40–100 °C @ 10 °C). It is observed that the NR dispersed system shows higher dielectric strength and low relaxation time with respect to NF dispersed system. The results suggest that the NR dispersed SPE possess enhanced properties and is more appropriate for an application in high energy density solid‐state Na ion batteries. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47361.