Blend Electrolytes Research Articles

Mg2+ Ion Conducting Biopolymer Blend Electrolytes Based on Starch/P(Vdf-Hfp) for Energy Storage Applications

Mg2+ Ion Conducting Biopolymer Blend Electrolytes Based on Starch/P(Vdf-Hfp) for Energy Storage Applications

INVESTIGATION OF PMMA AND PVdF-HFP WITH NaClO4POLYMER BLEND ELECTROLYTE SYSTEM– APPLICATION TO AN ELECTROCHEMICAL CELL

A solution-cast process was used to prepare pure poly (methyl methacrylate) (PMMA), and pure poly (vinylidene fluoride-hexafluoropropylene) (PVdF-HFP), their blend, and different weight percentages of sodium per chlorate (NaClO4) salt added to PMMA: PVdF-HFP polymer blend electrolyte thin films. The polymer electrolyte film was prepared using the solution cast process, which involves combining sodium per chlorate (NaClO4) ionic slat with poly (methyl methacrylate) (PMMA) and pure poly (vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) blended polymer. These films have been characterized systematically using different experimental techniques to investigate structural, morphological, thermal, and conductivity properties. The degree of crystallinity and porous microstructure of all the thin films were determined by XRD and SEM data and revealed that higher content of the amorphous nature was noticed at higher NaClO4 salt concentration in PMMA:PVdF-HFP polymer blend. When NaClO4 salt was added to a PMMA:PVdF-HFP polymer blend, fair complexation/interaction between polymers and salt was observed.In DSC curves of PMMA and PVdF-HFP polymers, a sharp melting temperature (Tm) was seen, which diminished when NaClO4 salt was added, showing that its amorphous nature had risen to prominence. The ionic conductivity of NaClO4 salt added PMMA:PVdF-HFP polymer blend electrolyte has been investigated, with an optimal value found to be1.55382 x 10-4S/cm at 40% NaClO4 salt. Electrochemical cells have been fabricated and investigated its characteristics in the configuration of Na/[PMMA:PVdF-HFP: NaClO4]/(I2:C).

Studies on H+ Ions Conducting Bio-Polymer Blend Electrolyte Based on Alginate-Pva Doped with Nh4no3

Studies on H+ Ions Conducting Bio-Polymer Blend Electrolyte Based on Alginate-Pva Doped with Nh4no3

Investigate the Thermal Analysis Properties of Polymer Electrolyte

Propylene carbonate (PC) (1:1) have been used as plasticizer to synthesized two series of polymer blend electrolytes (As and Cs) composed of Poly (methyl methacrylate) (PMMA)/Polyacrylonitrile (PAN), (80/20) Wt.% and ethylene carbonate (EC) using solution cast technique. Mixed iodide salts and varying weight ratio of potassium iodide (KI) and cesium iodide (CsI) was used to study the thermal properties of polymer blend electrolytes (GPEs). Differential Scanning Calorimeter (DSC) results show a decrease in the glass transition of electrolytes when increasing the weight percentage of salts, while the melting point increases due to the reduction in the polymer fluidity. Thermogravimetric analysis (TGA) indicates that the increase in the thermal stability can be attributed to the high thermal stability of polymer blend and the existence of the strong interaction between the two polymers. The optimum value of glass transition (Ts) is 104.2 °C found in sample containing 35 Wt.% of KI salt which has a melting point (Tm) 194.7 °C.

Study FTIR and AC Conductivity of Nanocomposite Electrolytes

In the present work polymer electrolytes were formulated using the solvent casting technique. Under special conditions, the electrolyte content was of fixed ratio of polyvinylpyrolidone (PVP): polyacrylonitrile (PAN) (25:75), ethylene carbonate (EC) and propylene carbonate (PC) (1:1) with 10% of potassium iodide (KI) and iodine I2 = 10% by weight of KI. The conductivity was increased with the addition of ZnO nanoparticles. It is also increased with the temperature increase within the range (293 to 343 K). The conductivity reaches maximum value of about (0.0296 S.cm-1) with (0.25 g) ZnO. The results of FTIR for blend electrolytes indicated a significant degree of interaction between the polymer blend (PVP and PAN) and the KI salt. From the electrolyte observations of the nanocomposites, the broad peak became narrower after adding the ZnO nanoparticle to the KI salt. The dielectric reaction decreased with the increase of the frequency at room temperature. The high dielectric permittivity of the polymer at lower frequencies can be attributed to the dipoles having sufficient time to get aligned with the electric field, resulting in higher polarization.

Polymer Blend Electrolytes for Batteries and Beyond

Polymer blend electrolytes are reemerging as an exciting class of industrially relevant electrolytes. They replace both the solvent and the salt of conventional electrolytes with polymers: termed p...

Extrusion of Polymer Blend Electrolytes for Solid-State Lithium Batteries: A Study of Polar Functional Groups

Extrusion of Polymer Blend Electrolytes for Solid-State Lithium Batteries: A Study of Polar Functional Groups

Structural and electrical properties of polyvinyl alcohol (PVA):Methyl cellulose (MC) based solid polymer blend electrolytes inserted with sodium iodide (NaI) salt

This paper studies the structural and electrical properties of solid polymer blend electrolytes based on polyvinyl alcohol (PVA) and methylcellulose (MC) incorporated with sodium iodide (NaI). The polymer electrolyte films were assembled through a solution casting technique. The host matrix, which is doped with different NaI salt concentrations between 10 and 50 wt%, utilizes the most amorphous blend compositions (60 wt% Polyvinyl alcohol and 40 wt% methylcellulose). The structural behaviour of the electrolyte films was examined utilizing X-ray diffraction (XRD) and Fourier transformation infrared (FTIR) techniques. The semi crystalline nature of PVA:MC with inserted NaI was derived from the X-ray diffraction studies, while the XRD analysis suggests that the highest ion conductive sample displays the minimum crystalline nature. The interaction between polymer blends and inserted salt was conceived from the FTIR investigation. Shifting of peaks and variation in the intensity of FTIR bands was detected. To investigate the structural properties and calculate the degree of crystallinity of the films, the (XRD) technique was employed, while electrical impedance spectroscopy (EIS) was utilized for studying the conductivity of the samples. In order to comprehend all of the electrical properties of the ion-conducting systems, the EIS outcome of each electrolyte was matched with Equivalent Electrical Circuits ( EEC) s. Ion transport parameters including mobility, carrier density and diffusion are well assessed for the samples and the dielectric properties were compared with the conductivity measurement. At lower frequencies, the dielectric constant was elevated and dielectric loss was detected. Loss tangent and electric modulus plots were used to study the relaxation nature of the samples. The highest ambient temperature conductivity of PVA loaded 50 wt% of NaI was determined to be 1.53 × 10 −5 S/cm. The loss tangent relaxation peak shifts towards high-frequency side which indicates the decrease of relaxation time and faster ion dynamics.

Design of plasticized proton conducting Chitosan:Dextran based biopolymer blend electrolytes for EDLC application: Structural, impedance and electrochemical studies

In this work, for the use of an electrical double-layer capacitor (EDLC) device applications, the fabrication and characterization of solid polymer electrolytes (SPEs) based on chitosan-dextran (CS-DN) blended polymer doped and plasticized with ammonium thiocyanate (NH 4 SCN) and glycerol are studied, respectively. The Fourier transform infrared (FTIR) spectroscopy method has been used to investigate the structural behavior of electrolytes. It was observed that the FTIR bands are shifted and decreased in their intensities with the increased glycerol plasticizer content and it results in the complex formation. According to the electrical impedance spectra (EIS), the electrolyte incorporated with high contents of plasticizer (42 wt%) revealed the highest ionic conductivity of (3.08 × 10 −4 S/cm). The electrical equivalent circuits (EEC) were used to investigate the circuit elements of the electrolytes further. Increasing glycerol plasticizers verified an improvement in ions density number (n), mobility (μ), and diffusion coefficient (D). The transference number measurements (TNM) indicated that the predominant charge carriers in the conduction process are ions where the ( t ion ) is 0.95. According to the linear sweep voltammetry (LSV) study, the uppermost conducting sample was found to have sufficient anode stability with a breakdown voltage of 1.9 V that can be used in electrochemical devices. The absence of peaks in the cyclic voltammetry (CV) demonstrated that the charge storage mechanism within the constructed EDLC is fully capacitive. Based on this finding, the starting specific capacitance ( C s ), energy density ( E d ), and power density ( P d ) have been identified to be 118F/g, 13.2 Wh/kg, and 1560 W/kg, respectively. Throughout its 100 cycles, the equivalence series resistance ESR value was between 53 and 117 Ω.

Characteristics of Plasticized Lithium Ion Conducting Green Polymer Blend Electrolytes Based on CS: Dextran with High Energy Density and Specific Capacitance.

The solution cast process is used to set up chitosan: dextran-based plasticized solid polymer electrolyte with high specific capacitance (228.62 F/g) at the 1st cycle. Fourier-transform infrared spectroscopy (FTIR) pattern revealed the interaction between polymers and electrolyte components. At ambient temperature, the highest conductive plasticized system (CDLG–3) achieves a maximum conductivity of 4.16 × 10−4 S cm−1. Using both FTIR and electrical impedance spectroscopy (EIS) methods, the mobility, number density, and diffusion coefficient of ions are measured, and they are found to rise as the amount of glycerol increases. Ions are the primary charge carriers, according to transference number measurement (TNM). According to linear sweep voltammetry (LSV), the CDLG–3 system’s electrochemical stability window is 2.2 V. In the preparation of electrical double layer capacitor devices, the CDLG–3 system was used. There are no Faradaic peaks on the cyclic voltammetry (CV) curve, which is virtually rectangular. Beyond the 20th cycle, the power density, energy density, and specific capacitance values from the galvanostatic charge–discharge are practically constant at 480 W/Kg, 8 Wh/Kg, and 60 F g−1, for 180 cycles.

Ionic Transport and Thermodynamic Interaction in Precision Polymer Blend Electrolytes for Lithium Batteries

AbstractSingle‐ion conducting polymer electrolytes are of interest for use with advanced battery electrodes such as lithium metal, but achieving sufficiently high conductivity has been challenging. In this work, a model system containing charged sites that are precisely spaced along the polymer backbone is explored. Precision sulfonated poly(4‐phenylcyclopentene) lithium salt (p5PhS‐Li) with a high degree of sulfonation (> 90%) is synthesized and blended with poly(ethylene oxide) (PEO) to investigate the thermodynamic and transport properties. Melting point depression is measured via differential scanning calorimetry, ionic conductivity,κ, is determined using electrochemical impedance spectroscopy, and the fraction of current carried by Li+is estimated based on steady‐state current measurements. In conjunction with a density measurement, melting point depression is used to find an effective Flory–Huggins interaction parameter,χeff= − 0.21, suggesting miscibility of the blend.κspans a large range from 2 × 10−11to 2 × 10−7S cm−1over the composition and temperature range investigated. The fraction of charge carried by lithium ions also spans a significant range from 0.12 in majority PEO blend to 0.98 in majorityp5PhS‐Li blend. This study addresses several limitations of sulfonated polystyrene and opens up the possibility of precisely controlling the spacing of other anion types.

Impact of nano-titania and ultrasonic irradiation on the physical properties of polymer blend electrolytes

Nanocomposite polymer blend electrolytes (NCPBEs) consisting of poly(ethylene oxide) and poly(vinylidene fluoride-co-hexafluoropropylene) as polymers, lithium triflate (LiCF3SO3) as an electrolyte and nano-titania (TiO2) as a filler were prepared by both conventional stirring and ultrasonic irradiation methods. Complex formation and an increase in the amorphicity of the sample were confirmed through X-ray diffraction analysis. From alternating current impedance spectroscopy studies, it was observed that the ultrasonically irradiated NCPBEs exhibited maximum ionic conductivity compared with the NCPBEs prepared through conventional mechanical stirring. The Arrhenius behavior was observed from temperature-dependent ionic conductivity studies. Wagner’s polarization studies revealed that the charge transport in the prepared NCPBEs was predominantly due to ions. The dielectric behavior was analyzed by complex dielectric permittivity (ε*) and loss tangent studies. Notable morphological changes of the samples were observed from scanning electron microscopy and atomic force microscopy studies. From thermogravimetry–differential thermal analysis, the sample with the maximum ionic conductivity was found to be thermally stable up to 300°C.

Structural and electrochemical studies of proton conducting biopolymer blend electrolytes based on MC:Dextran for EDLC device application with high energy density

This study shows preparation and characterization of solid biopolymer electrolyte based on glycerolized methylcellulose (MC): dextran-doped with ammonium thiocyanate (NH4SCN). The nature of electrolyte composition in terms of interaction is characterized using Fourier transform infrared (FTIR) technique. Lowering and shifting in the intensity of the bands are observed with increasing the quantity of glycerol as a plasticizer, confirming complexation between electrolyte components. Ion transport parameters are determined using both of the methods of EIS and FTIR where the parameters are found to be increased with glycerol concentration. The transport number measurement indicates that ions are the primary charge carrier in the conduction mechanism where tion is found to be 0.961. The maximum DC ionic conductivity value is achieved that found to be 1.63 × 10−3 S cm−1. The ESR values are ranged from 300 to 580 Ω throughout 450 cycles. The technique of linear sweep voltammetry (LSV) shows the electrochemical stability window of 2 V for the conducting samples. The response of cyclic voltammetry (CV) shows an almost rectangular shape without Faradaic peaks. A galvanostatic charge–discharge investigation has shown the initial specific capacitance, energy density, and power density are 133 F g−1, 18.3 Wh Kg−1, and 680 W Kg−1, respectively.

Correlation Study on Biopolymer-Blended Cobalt and Iodine Gel Electrolytes to Enhance the Efficiency of Natural Dye-Based DSSCs

In this study, we prepared a new natural sensitizer from blood berry extract (BB dye) and coupled it with a series of biopolymer gel electrolytes consisting of Co2+/3+ or I–/I3–, such as GE 1, GE 2, GE 3, GE 4, GE 5, and GE 6. An as-prepared natural dye was characterized via UV–visible spectroscopy to confirm the behavior of the dye, which showed an absorption range at 484 nm. The interaction between the TiO2 surface and the BB dye was analyzed by density functional theory (DFT) studies. All six biogel electrolytes were characterized using Fourier transform infrared (FTIR), UV, X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and cyclic voltammetry (CV) techniques to validate the integration of redox mediators into polymer hosts. The bioelectrolytes GE 1, GE 2, GE 4, and GE 5 contain a single polymer matrix (xanthan gum or gelatin) and showed a very low photo-conversion efficiency. At the same time, GE 3 and GE 6 contain a blended polymer matrix (xanthan gum and gelatin) and achieved a higher power conversion efficiency (PCE) of 0.86 and 2.06%, respectively, under 1 sun illumination. The redox mediator Co2+/3+ or I–/I3– incorporated into both single and blended polymer matrixes played a vital role in regenerating the BB dye. In this case, the bioblended polymer gel electrolyte (GE 6) consisting of a Co2+/3+ redox pair attained a high conductivity of 5.97 × 10–5 S/cm–1 and a chemical capacitance of 15.02 ×10–6 F compared to the I–/I3–-incorporated electrolyte. The PCE reports were sustained by the electrochemical impedance spectrum results such as a larger charge at the Pt/electrolyte interface, a lower charge transfer resistance at the TiO2/dye/electrolyte interface, and a higher chemical capacitance. The introduction of a biopolymer cobalt redox-based gel electrolyte with the natural BB dye improves the electron lifetime and readily reduces the recombination reaction. The integration of a natural dye with a blended biopolymer gel electrolyte can pave the way to generate new eco-friendly dye-sensitized solar cells (DSSCs) with high stability.

A blended gel polymer electrolyte for dendrite-free lithium metal batteries

Solid-state lithium metal batteries (SSLMBs) are promising candidates for the application in electric vehicles (EVs) because of their higher energy density and safer properties compared to the traditional liquid organic electrolyte-based lithium-ion batteries (LIBs). However, SSLMBs with solid polymer electrolyte (SPE) suffer from the serious lithium dendrite problem, which results in the poor cycling performance and the short circuit of batteries. In this work, a thin and flexible blended gel polymer electrolyte (GPE) was prepared for dendrite free SSLMBs. The as-prepared GPE has a strong strain at 529.94 ± 10%, a high ion transference number (tLi+) of 0.66, and a wide electrochemical window of 5.23 V (vs. Li+/Li). Mechanism study shows that the addition of fluoroethylene carbonate (FEC) into the GPE promotes the formation of LiF-coating solid electrolyte interphase (SEI). As a result, a stable GPE/Li-metal interface and dendrite-free SSLMB was achieved. Moreover, the solid-state battery with Li-metal anode, as-prepared SPE and LiFePO4 can deliver a specific capability of 150 mAh g−1 and a capacity retention of 94.8 % after 500 cycles at 0.3C, 20 ℃.

Dual-Salt Electrolytes to Effectively Reduce Impedance Rise of High-Nickel Lithium-Ion Batteries

Simply mixing several lithium salts in one electrolyte to obtain blended salt electrolytes has been demonstrated as a promising strategy to formulate advanced electrolytes for lithium metal batteries (LMBs) and lithium-ion batteries (LIBs). In this study, we report the use of dual-salt electrolytes containing lithium hexafluorophosphate (LiPF6) and lithium difluorophosphate (LiDFP) in ethylene carbonate/ethyl methyl carbonate (EC/EMC) mixture and tested them in layered high-nickel LIB cells. LiNi0.94Co0.06O2 was synthesized through a coprecipitation method and was used as a representative high-nickel cathode for the U.S. DOE realizing next-generation cathode (RNGC) deep dive program. The ionic conductivity of dual-salt electrolytes can be maintained by controlling the amount of LiDFP. Techniques including 1H Nuclear Magnetic Resonance (NMR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-mass spectrometry (ICP-MS), and differential voltage analysis (DVA) were used to understand the improved performance. The multifaceted benefits of using the dual-salt electrolytes include (1) reduced transesterification, (2) formation of a stable cathode electrolyte interface, and (3) mitigation of cathode degradation at high voltages, especially stabilization of oxide particles during the H2 ↔ H3 transformation.

Preparation and characterization of proton conducting polymer blend electrolytes (PVC/PMMA/NH4SCN)

Preparation and characterization of proton conducting polymer blend electrolytes (PVC/PMMA/NH4SCN)

Structural, morphological and electrical properties of chitosan/methylcellulose blend polymer doped with different concentrations of NH4NO3

Polymer blend electrolytes based on chitosan: methylcellulose loaded with ammonium nitrate (NH4NO3) were fabricated by solution cast method and characterized by XRD, FTIR, EIS, FESEM, and TNM techniques. XRD is used to show the decrease of the crystalline structure. FTIR method is used to confirm the interaction between electrolyte elements. The maximum room temperature DC conductivity of 3.54 × 10−4 S cm−1 is provided by the highest conducting system using EIS data. The FESEM method showed that the morphology of the film has a uniform smooth surface at the highest salt concentration. This is in good agreement with the XRD, FTIR, and EIS results. The dielectric constant is high at the low frequency region due to electrode polarization. Transference number measurement (TNM) is used to show the dominant charge carriers. The values of the transference number of electron (telectron) and ion (tion) showed that the ions are dominant. The TNM measurement shows the compatibility of the system for electrochemical energy storage device application.

Effect of ionic liquid on structural, thermal and electrical transport properties of PVA-PVP based polymer blend electrolyte membrane

The present paper deals with the loading effect of ionic liquid (IL), 1-ethyl-3-methylimidazolium methylsulfate [EMIM][MS] on structural and electrical transport properties of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG)- salt, sodium methyl sulfate (MeSO4Na) based polymer blend electrolyte (PBE) films. The samples were prepared using conventional solution cast method. The x-ray Diffraction (XRD) result shows that PBE films has characteristic peak with broad halo appeared in the range 2θ = 19.95° to 22.72° reveals the amorphous nature (semi-crystalline).The % degree of crystalinity (X c ) of prepared IL based PBE films were found to decreases with increasing IL content. Fourier transform infrared (FTIR) in total attenuated reflectance (ATR) mode analysis reveals the interaction between the functional groups (C=O and O–H) of polymer electrolyte with the cation, EMIM+/anion of IL/salt. Thermogravimetric analysis (TGA) shows that IL based PBE samples decomposes in multistep and Td,onset/peak value decreases with IL loading. Sample containing 30 wt%IL shows optimum dc conductivity value ∼1.5 × 10−4 S cm−1 at 30 °C with minimum activation energy ∼0.21 eV. Logσ versus 1000/T plot for all PBE sample follow the Arrhenius type thermally activated process and activation energy decreased with increasing IL content in PBE films. Frequency dependent conductivity behavior for IL based PBE film follow the Jonscher’s power law with power law exponent, n value<1 (amorphous polymeric system). AC conductivity spectra and loss tangent spectra (tanδ) with respect to IL/temperature content scalled successfully. Dielectric relaxation behavior and conductivity relaxation were analyses with respect to IL content and temperature. Mobility, total number of charge/ion density, ion diffusivity was estimated. Ionic transference number (ITN) measurement (tion ∼0.98, tele ∼0.02) reveals that ions are principal charge carriers in present system. Linear sweep voltametry (LSV) and cyclic voltamerty (CV) measurements show that 30 wt%IL containing sample has electrochemical stability window (ESW) ∼±2.7volt and Faradic oxidation reduction peaks were observed, respectively.

Titanium dioxide nano-ceramic filler in solid polymer electrolytes: Strategy towards suppressed dendrite formation and enhanced electrochemical performance for safe lithium ion batteries

Solid polymer electrolytes (SPEs) in lithium-ion batteries (LIBs) are emerging as promising alternative for liquid electrolytes. However, one of the drawbacks of SPEs is incompatibility between lithium metal anode/electrolyte that leads to the low ionic conductivity and lower cycling performance of LIBs. The present study show that fabrication of free-standing flexible hybrid solid polymer electrolyte (HSPE) based on poly(vinylidene fluoride-co-hexafluoro propylene)/poly(vinyl acetate) polymer blend electrolyte with TiO2 nano-ceramic filler (NCF). The incorporation of TiO2-NCF aids in simultaneous improvements of the ionic conductivity and mechanical properties of host matrix. HSPE with 7.5 wt% TiO2 exhibits highest ionic conductivity of 2.69 × 10−3 S cm−1 at 30 °C, which is ~2.5 time higher than ceramic free HSPE. In addition, the incorporation of TiO2 enhances the high thermal stability (thermal degradation at 350 °C) and mechanical strength (stress 8.4 MPa) of the HSPE. Remarkably, HSPE with 7.5 wt% TiO2-NCF possess large Li+ transference number (0.53) with extended electrochemical stability window (5.4 V) and superior compatibility with lithium metal which is highly desirable for high voltage LIBs. The Li/HSPE/LiFePO4 cell showed superior charge discharge properties, cycling stability and rate capability. Suppression of growth and proliferation of Li dendrites was demonstrated by time dependent impendence analysis. Furthermore, density functional theory (DFT) calculations confirm the mutual interactions between TFSI− and ions in electrolytes and that between TiO2 segments and polymer segments. This work exemplifies the significant role of TiO2-NCF in enhanced electrochemical performance of polymer based free standing flexible HSPE.