scholarly journals A single cation or anion dendrimer-based liquid electrolyte

2016 ◽  
Vol 7 (5) ◽  
pp. 3390-3398 ◽  
Author(s):  
Sudeshna Sen ◽  
Rudresha B. Jayappa ◽  
Haijin Zhu ◽  
Maria Forsyth ◽  
Aninda J. Bhattacharyya
Keyword(s):  
Ion Transport ◽  
Transference Number ◽  
Liquid Electrolyte ◽  
Ion Conductor ◽  
Ionic Transference Number ◽  
Anion Diffusion

The proposed dendrimer based liquid electrolyte is a single-ion conductor where ion transport is altered by the nature of the chemical functionalities leading to large variations in anion diffusion and hence ionic transference number.

scholarly journals Structural, Electrical and Electrochemical Properties of Glycerolized Biopolymers Based on Chitosan (CS): Methylcellulose (MC) for Energy Storage Application

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1183
Author(s):  
Shujahadeen B. Aziz ◽  
Ahmad S. F. M. Asnawi ◽  
Mohd Fakhrul Zamani Kadir ◽  
Saad M. Alshehri ◽  
Tansir Ahamad ◽  
...  
Keyword(s):  
Energy Storage ◽  
Ion Transport ◽  
Ammonium Thiocyanate ◽  
Transference Number ◽  
Ionic Mobility ◽  
Transport Parameters ◽  
Ionic Transference Number ◽  
Energy Storage Application ◽  
Electrochemical Double Layer ◽  
Ion Conducting

In this work, a pair of biopolymer materials has been used to prepare high ion-conducting electrolytes for energy storage application (ESA). The chitosan:methylcellulose (CS:MC) blend was selected as a host for the ammonium thiocyanate NH4SCN dopant salt. Three different concentrations of glycerol was successfully incorporated as a plasticizer into the CS–MC–NH4SCN electrolyte system. The structural, electrical, and ion transport properties were investigated. The highest conductivity of 2.29 × 10−4 S cm−1 is recorded for the electrolyte incorporated 42 wt.% of plasticizer. The complexation and interaction of polymer electrolyte components are studied using the FTIR spectra. The deconvolution (DVN) of FTIR peaks as a sensitive method was used to calculate ion transport parameters. The percentage of free ions is found to influence the transport parameters of number density (n), ionic mobility (µ), and diffusion coefficient (D). All electrolytes in this work obey the non-Debye behavior. The highest conductivity electrolyte exhibits the dominancy of ions, where the ionic transference number, tion value of (0.976) is near to infinity with a voltage of breakdown of 2.11 V. The fabricated electrochemical double-layer capacitor (EDLC) achieves the highest specific capacitance, Cs of 98.08 F/g at 10 mV/s by using the cyclic voltammetry (CV) technique.

Effect of Plasticizers on Ion Transport Properties of PEO+NH4PF6 Polymer Electrolyte System – Dielectric Studies

2011 ◽  
Vol 110-116 ◽  
pp. 278-284
Author(s):  
Kuldeep Mishra ◽  
D.K. Rai
Keyword(s):  
Ion Transport ◽  
Polymer Electrolyte ◽  
Room Temperature ◽  
Humidity Sensor ◽  
Transference Number ◽  
Electrolyte System ◽  
Free Standing ◽  
Casting Technique ◽  
Ionic Transference Number ◽  
Solution Casting Technique

Dielectric properties of proton conducting polymer electrolyte system, containing polyethylene oxide (PEO) as host polymer and ammonium hexfluorophosphate (NH4PF6) as complexing salt plasticized with EC and EC:PC, are investigated. The free standing films of thickness ~ 200 - 300µm are synthesized by solution casting technique. The electrical conductivity studies show that plasticization of the polymer electrolyte results into an enhancement in its conductivity by about two orders of magnitude. The maximum room temperature bulk conductivity is obtained to be ~ 10-5 S/cm for the plasticized polymer electrolyte. To understand the ion transport mechanism, different frequency dependent parameters are measured like dielectric permittivity, loss tangent and AC conductivity. The ionic transference number of the prepared systems is found to be close to unity which shows ion dominant charge transport in the electrolyte system. The conductivity of the polymer electrolyte has been found to be very sensitive to the relative humidity, which makes it a good candidate for its application for humidity sensor.

Enhanced Ion Transport in an Ether Aided Super Concentrated Ionic Liquid Electrolyte for Long-Life Practical Lithium Metal Battery Applications

2020 ◽  
Author(s):  
Urbi Pal ◽  
Fangfang Chen ◽  
Derick Gyabang ◽  
Thushan Pathirana ◽  
Binayak Roy ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ion Transport ◽  
Current Density ◽  
Coulombic Efficiency ◽  
High Energy ◽  
Liquid Electrolyte ◽  
High Mass ◽  
Lithium Metal ◽  
Ionic Liquid Electrolyte ◽  
Lithium Metal Battery

We explore a novel ether aided superconcentrated ionic liquid electrolyte; a combination of ionic liquid, <i>N</i>-propyl-<i>N</i>-methylpyrrolidinium bis(fluorosulfonyl)imide (C<sub>3</sub>mpyrFSI) and ether solvent, <i>1,2</i> dimethoxy ethane (DME) with 3.2 mol/kg LiFSI salt, which offers an alternative ion-transport mechanism and improves the overall fluidity of the electrolyte. The molecular dynamics (MD) study reveals that the coordination environment of lithium in the ether aided ionic liquid system offers a coexistence of both the ether DME and FSI anion simultaneously and the absence of ‘free’, uncoordinated DME solvent. These structures lead to very fast kinetics and improved current density for lithium deposition-dissolution processes. Hence the electrolyte is used in a lithium metal battery against a high mass loading (~12 mg/cm<sup>2</sup>) LFP cathode which was cycled at a relatively high current rate of 1mA/cm<sup>2</sup> for 350 cycles without capacity fading and offered an overall coulombic efficiency of >99.8 %. Additionally, the rate performance demonstrated that this electrolyte is capable of passing current density as high as 7mA/cm<sup>2</sup> without any electrolytic decomposition and offers a superior capacity retention. We have also demonstrated an ‘anode free’ LFP-Cu cell which was cycled over 50 cycles and achieved an average coulombic efficiency of 98.74%. The coordination chemistry and (electro)chemical understanding as well as the excellent cycling stability collectively leads toward a breakthrough in realizing the practical applicability of this ether aided ionic liquid electrolytes in lithium metal battery applications, while delivering high energy density in a prototype cell.

Electronic/Ionic Conductivity and Oxygen Diffusion Coefficient af the Sr-Fe-Co-O System

1995 ◽  
Vol 393 ◽  
Author(s):  
B. Ma ◽  
J.-H. Park ◽  
C. U. Segre ◽  
U. Balachandran
Keyword(s):  
Diffusion Coefficient ◽  
Ionic Conductivity ◽  
Oxygen Diffusion ◽  
Ionic Conductivities ◽  
Transference Number ◽  
Transference Numbers ◽  
Oxygen Diffusion Coefficient ◽  
Ionic Transference Number ◽  
Local Fitting ◽  
Oxide Ion

ABSTRACTOxides in the Sr-Fe-Co-O system exhibit both electronic and ionic conductivities. Recently, the Sr-Fe-Co-O system attracted great attention because of its potential to be used for oxygen-permeable membranes that can operate without electrodes or external electrical circuitry. Electronic and ionic conductivities of two compositions of the Sr-Fe-Co-O system, named SFC-1 and SFC-2, have been measured at various temperatures. The electronic transference number is much greater than the ionic transference number in SFC-1, whereas the electronic and ionic transference numbers are very similar in SFC-2. At 800°C, the electronic and ionic conductivities are ≈76 and ≈4 S•cm−1, respectively, for SFC-1; whereas, for SFC-2, the electronic and ionic conductivities are ≈10 and ∼1 S•cm−1, respectively. By performing a local fitting to the equation σ • T = Aexp(-Ea / kT), we found that the oxide ion activation energies are 0.92 and 0.37 eV, respectively, for SFC-1 and SFC-2. The oxygen diffusion coefficient of SFC-2 is ≈ 9 x 10−7cm2/sec at 900°C.

Ionic Conductivity, Morphology and Transport Number of Lithium Ions in PMMA Based Gel Polymer Electrolytes

2013 ◽  
Vol 334-335 ◽  
pp. 137-142 ◽  
Author(s):  
Lisani Othman ◽  
Khairul Bahiyah Md. Isa ◽  
Zurina Osman ◽  
Rosiyah Yahya
Keyword(s):  
Ionic Conductivity ◽  
Salt Concentration ◽  
Polymer Electrolytes ◽  
Ethylene Carbonate ◽  
Transference Number ◽  
Gel Polymer Electrolytes ◽  
Casting Technique ◽  
Ionic Transference Number ◽  
Temperature Dependence Of Conductivity ◽  
Solution Casting Technique

The gel polymer electrolytes (GPEs) composed of polymethylmethacrylate (PMMA) with lithium trifluoromethanesulfonate (LiCF3SO3) salt dissolved in a binary mixture of ethylene carbonate (EC) and propylene carbonate (PC) organic solvents have been prepared by the solution casting technique. The samples are prepared by varying the salt concentrations from 5 wt.% to 30 wt.%. Impedance spectroscopy measurement has been carried out to determine the ionic conductivity of the samples. The sample containing 25 wt.% of LiCF3SO3salt exhibits the highest room temperature ionic conductivity of 2.56 x 10-3S cm-1. The conductivity of the GPEs has been found to depend on the salt concentration added to the sample, while at higher salt concentration reveals a decrease in the ionic conductivity due to ions association. The temperature dependence of conductivity from 303 K to 373 K is found to obey the Arrhenius law. The ionic transference number,tiof GPEs has been estimated by the DC polarization method and the value is found to be 0.98, 0.93, and 0.97 for the sample containing 25 wt.%, 5 wt.% and 30 wt.% respectively. This result is consistent with the conductivity studies.

scholarly journals The Study of Structural, Impedance and Energy Storage Behavior of Plasticized PVA:MC Based Proton Conducting Polymer Blend Electrolytes

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5030 ◽  
Author(s):  
Shujahadeen B. Aziz ◽  
Iver Brevik ◽  
M. A. Brza ◽  
A. S. F. M. Asnawi ◽  
Elham M. A. Dannoun ◽  
...  
Keyword(s):  
Energy Storage ◽  
Ionic Conductivity ◽  
Specific Capacitance ◽  
High Efficiency ◽  
Ammonium Thiocyanate ◽  
Transference Number ◽  
Equivalent Series Resistance ◽  
Ionic Transference Number ◽  
Main Charge ◽  
Electrochemical Double Layer

In this study, structural characterization, electrical properties and energy storage performance of plasticized polymer electrolytes based on polyvinyl alcohol/methylcellulose/ammonium thiocyanate (PVA/MC-NH4SCN) were carried out. An X-ray diffraction (XRD) study displayed that the plasticized electrolyte system with the uppermost value of direct current (DC) ionic conductivity was the most amorphous system. The electrolyte in the present work realized an ionic conductivity of 2.903 × 10−3 Scm−1 at room temperature. The main charge carrier in the electrolyte was found to be the ions with the ionic transference number (tion) of 0.912, compared to only 0.088 for the electronic transference number (telec). The electrochemical stability potential window of the electrolyte is 2.1 V. The specific capacitance was found to reduce from 102.88 F/g to 28.58 F/g as the scan rate increased in cyclic voltammetry (CV) analysis. The fabricated electrochemical double layer capacitor (EDLC) was stable up to 200 cycles with high efficiency. The specific capacitance obtained for the EDLC by using charge–discharge analysis was 132.7 F/g at the first cycle, which is slightly higher compared to the CV plot. The equivalent series resistance (ESR) increased from 58 to 171 Ω throughout the cycles, which indicates a good electrolyte/electrode contact. Ions in the electrolyte were considered to have almost the same amount of energy during the conduction process as the energy density is approximately at 14.0 Wh/kg throughout the 200 cycles. The power density is stabilized at the range of 1444.3 to 467.6 W/kg as the EDLC completed the cycles.

Structural, Electrical and Electrochemical Properties of Mg0.55Si1.9Al0.1Fe0.1(PO4)3 Ceramic Electrolytes

2017 ◽  
Vol 20 (3) ◽  
pp. 135-140 ◽  
Author(s):  
Nurul Akmaliah Dzulkurnain ◽  
N. A. Mustaffa ◽  
N. S. Mohamed
Keyword(s):  
Electrochemical Properties ◽  
Ion Mobility ◽  
Sol Gel ◽  
Linear Sweep Voltammetry ◽  
Transference Number ◽  
X Ray Diffraction ◽  
Ionic Transference Number ◽  
Ceramic Electrolytes ◽  
Gel Technique ◽  
Mobile Ions

This study was undertaken to investigate the structural, electrical and electrochemical properties of Fe3+ substituted Mg0.55Si1.9Al0.1(PO4)3 compound synthesized by water-based sol–gel technique. X-ray diffraction showed that the compound crystallized in monoclinic crystalline phase with a space group of P1 21/c1. The sample sintered at 850 ˚C exhibited the highest conductivity of 1.42 × 10-6 S cm-1 at 373 K since it contained the highest number of mobile ions. It also exhibited the highest value of ion mobility, μ of 1.13 × 10-11 cm2 V-1 s-1 at ambient temperature which was attributed to the optimum size of migration channel as indicated by its unit cell volume. Linear sweep voltammetry result showed that the Mg0.55Si1.9Al0.1Fe0.1(PO4)3 was electrochemically stable up to 3.0 V. Meanwhile, its ionic transference number of 0.99 suggested that the majority of the mobile charge carriers were mainly to ions, expected to be Mg2+ ions.

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