EFFECT OF CONCENTRATION AND NATURE OF LITHIUM SALT ON CHARACTERISTICS OF GEL ELECTROLYTES DMSO-PVDF-LiAn

The results of the study of electrolytes based on gel solutions of DMSO-PVDF-lithium salt with concentrations up to 0.05 m.f. and above 0.1 m.f. are presented. It is shown that the conductivity of electrolytes is close to the conductivity of lithium salt solutions in pure DMSO and obeys the Arrhenius equation in the studied range of temperatures and concentrations. The calculated activation energies for electrolytes with a salt concentration of up to 0.05 m.f. are 14–15.4 KJ/Mol, and for electrolytes with a salt concentration above 0.1 m.f. - 16.9–20.6 KJ/Mol indicate a fast ion transfer, which in more concentrated solutions is inhibited by an increase in their crystallinity. The analysis of the equivalent circuit models of the Li-Li systems electrochemical impedance spectra showed the tendency of electrolytes to form capacitive elements at the lithium electrode-electrolyte interface. It was recognized the presence of semi-infinite diffusion in LiClO4 and LiIm with salt concentration of 0.05 m.f., due to the imperfection of the film formed on the electrode surface. The efficiency of using DMSO-PVDF-lithium gel electrolytes on steel and platinum electrodes was analyzed by voltammograms.

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Fast ion transport in new lithium electrolytes gelled with PMMA. 2. Influence of lithium salt concentration

Solid State Ionics ◽

10.1016/0167-2738(93)90033-y ◽

1993 ◽

Vol 66 (1-2) ◽

pp. 105-112 ◽

Cited By ~ 98

Author(s):

O BOHNKE ◽

G FRAND ◽

M REZRAZI ◽

C ROUSSELOT ◽

C TRUCHE

Keyword(s):

Ion Transport ◽

Salt Concentration ◽

Lithium Salt ◽

Fast Ion

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A Comparison of Different Ways of Mixing the Lithium Salt on the Electrochemical Properties for Li[Li0.2Mn0.54Ni0.13Co0.13]O2 Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.744 ◽

2017 ◽

Vol 727 ◽

pp. 744-750

Author(s):

Min Luo ◽

Ran Zhang ◽

Meng Wang ◽

Yun Bo Chen ◽

Mo Chu

Keyword(s):

Discharge Capacity ◽

Cathode Materials ◽

Lithium Salt ◽

Electrochemical Impedance ◽

Rate Capability ◽

Precipitation Method ◽

Electrochemical Impedance Spectra ◽

Primary Particles ◽

Small Primary ◽

Co Precipitation

Li-rich layered cathode materials Li [Li0.2Mn0.54Ni0.13Co0.13]O2 with spherical morphology were synthesized via a co-precipitation method by different ways of mixing the lithium salt. The cathode materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM). The results show that Li [Li0.2Mn0.54Ni0.13Co0.13]O2 with a well-ordered layered structure consists of small primary particles ranging from 180 to 370 nm. By comparation, the primary particles of T2 (mixing with Li2CO3 after preheating carbonate precursor) is smaller. Electrochemical measurements have also been employed, including charge-discharge, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS). It is demonstrated that T2 exhibits significant improvements on the electrochemical performance, especially the rate capability. The discharge capacity is 211 mAh g−1 at 1C for T2 electrode, and still maintains an discharge capacity of 158.8mAh g−1 at 4C. It is believed that the remarkably enhanced rate capability might be ascribed to mixing with Li2CO3 after preheating by changing the way of mixing with Li2CO3.

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The study of the electrochemical properties of zinc-rich coating on the base of water sodium silicate

Practice of Anticorrosive Protection ◽

10.31615/j.corros.prot.2019.94.4-6 ◽

2019 ◽

Vol 24 (4) ◽

pp. 51-58

Author(s):

Le Hong Quan ◽

Nguyen Van Chi ◽

Mai Van Minh ◽

Nong Quoc Quang ◽

Dong Van Kien

Keyword(s):

Carbon Steel ◽

Electrochemical Properties ◽

Sodium Silicate ◽

Cathodic Protection ◽

Electrochemical Impedance ◽

Steel Substrate ◽

Electrical Contact ◽

Electrochemical Impedance Spectra ◽

Pure Zinc ◽

Electric Circuits

The study examines the electrochemical properties of a coating based on water sodium silicate and pure zinc dust (ZSC, working title - TTL-VN) using the Electrochemical Impedance Spectra (EIS) with AutoLAB PGSTAT204N. The system consists of three electrodes: Ag/AgCl (SCE) reference electrode in 3 M solution of KCl, auxiliary electrode Pt (8x8 mm) and working electrodes (carbon steel with surface treatment up to Sa 2.5) for determination of corrosion potential (Ecorr) and calculation of equivalent electric circuits used for explanation of impedance measurement results. It was shown that electrochemical method is effective for study of corrosion characteristics of ZSC on steel. We proposed an interpretation of the deterioration over time of the ability of zinc particles in paint to provide cathodic protection for carbon steel. The results show that the value of Ecorr is between -0,9 and -1,1 V / SCE for ten days of diving. This means that there is an electrical contact between the zinc particles, which provides good cathodic protection for the steel substrate and most of the zinc particles were involved in the osmosis process. The good characteristics of the TTL-VN coating during immersion in a 3,5% NaCl solution can also be explained by the preservation of corrosive zinc products in the coating, which allows the creation of random barrier properties.

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Antireflection Improvement and Junction Quality Optimization of Si/PEDOT:PSS Solar Cell with the Introduction of Dopamine@Graphene

Energies ◽

10.3390/en13225986 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5986

Author(s):

Tao Chen ◽

Hao Guo ◽

Leiming Yu ◽

Tao Sun ◽

Anran Chen ◽

...

Keyword(s):

Solar Cell ◽

Conversion Efficiency ◽

High Performance ◽

Electrochemical Impedance ◽

Short Circuit ◽

Short Circuit Current ◽

Electrochemical Impedance Spectra ◽

Solar Cell Performance ◽

Photovoltaic Conversion ◽

Photovoltaic Conversion Efficiency

Si/PEDOT: PSS solar cell is an optional photovoltaic device owing to its promising high photovoltaic conversion efficiency (PCE) and economic manufacture process. In this work, dopamine@graphene was firstly introduced between the silicon substrate and PEDOT:PSS film for Si/PEDOT: PSS solar cell. The dopamine@graphene was proved to be effective in improving the PCE, and the influence of mechanical properties of dopamine@graphene on solar cell performance was revealed. When dopamine@graphene was incorporated into the cell preparation, the antireflection ability of the cell was enhanced within the wavelength range of 300~450 and 650~1100 nm. The enhanced antireflection ability would benefit amount of the photon-generated carriers. The electrochemical impedance spectra test revealed that the introduction of dopamine@graphene could facilitate the separation of carriers and improve the junction quality. Thus, the short-circuit current density and fill factor were both promoted, which led to the improved PCE. Meanwhile, the influence of graphene concentration on device performances was also investigated. The photovoltaic conversion efficiency would be promoted from 11.06% to 13.15% when dopamine@graphene solution with concentration 1.5 mg/mL was applied. The achievements of this study showed that the dopamine@graphene composites could be an useful materials for high-performance Si/PEDOT:PSS solar cells.

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Performance of Ba0.5Sr0.5Co0.8Fe0.2O3-δ-Ag Composite Cathode Materials for IT-SOFCs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.2309 ◽

2011 ◽

Vol 311-313 ◽

pp. 2309-2314 ◽

Cited By ~ 2

Author(s):

Wen Xia Zhu ◽

Zhe Lü ◽

Le Xin Wang ◽

Xiao Yan Guan ◽

Xin Yan Zhang

Keyword(s):

Solid Oxide Fuel Cells ◽

Electrochemical Impedance ◽

Composite Cathode ◽

Solid Oxide ◽

Electrode Polarization ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Composite Cathodes ◽

Reduced Temperature ◽

Resistance Value

°Abstract. In order to develop new cathodes for reduced temperature SOFCs, Ba0.5Sr0.5Co0.8Fe0.2O3-δ-Ag composite cathode was investigated in intermediate-temperature Solid Oxide Fuel Cells (IT-SOFCs). The XRD results suggested that no chemical reactions between BSCF and Ag in the composite cathode were found. The resistance measurements showed that the addition of Ag into BSCF improved electrical conductivity of pure BSCF, and the improved conductivity resulted in attractive cathode performance. In addition, electrochemical impedance spectra exhibited the better performance of BSCF-Ag composite cathodes than pure BSCF, e.g., the polarization resistance value of BSCF-Ag was only 0.36Ω cm2 at 650°C, which was nearly 80% lower than that of BSCF electrode. Polarization curves showed the overpotential decreased with the addition of Ag. The current density value of BSCF-Ag was 0.88Acm-2 under –120mV, about five times of that BSCF measured at 650°C. As a summary, compared to a pure BSCF cathode, it was found that adding Ag in the cathode enhanced the BSCF performance significantly.

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Effect of lithium salt concentration in PVAc/PMMA-based gel polymer electrolytes

Ionics ◽

10.1007/s11581-009-0329-1 ◽

2009 ◽

Vol 16 (1) ◽

pp. 27-32 ◽

Cited By ~ 34

Author(s):

S. Rajendran ◽

V. Shanthi Bama ◽

M. Ramesh Prabhu

Keyword(s):

Salt Concentration ◽

Polymer Electrolytes ◽

Lithium Salt ◽

Gel Polymer Electrolytes

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Electrochemical Performance Optimization of Li2NixFe1−xSiO4 Cathode Materials for Lithium-Ion Batteries

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4036318 ◽

2017 ◽

Vol 14 (2) ◽

Cited By ~ 1

Author(s):

Atef Y. Shenouda ◽

M. M. S. Sanad

Keyword(s):

Performance Optimization ◽

Electrochemical Impedance ◽

Coulombic Efficiency ◽

Sol Gel ◽

Lithium Ion ◽

Electrochemical Impedance Spectra ◽

Cell Parameters ◽

Sol Gel Process ◽

Eis Measurements ◽

And Function

Li2NixFe1−xSiO4 (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) samples were prepared by sol–gel process. The crystal structure of prepared samples of Li2NixFe1−xSiO4 was characterized by XRD. The different crystallographic parameters such as crystallite size and lattice cell parameters have been calculated. Scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) investigations were carried out explaining the morphology and function groups of the synthesized samples. Furthermore, electrochemical impedance spectra (EIS) measurements are applied. The obtained results indicated that the highest conductivity is achieved for Li2Ni0.4Fe0.6SiO4 electrode compound. It was observed that Li/Li2Ni0.4Fe0.6SiO4 battery has initial discharge capacity of 164 mAh g−1 at 0.1 C rate. The cycle life performance of all Li2NixFe1−xSiO4 batteries was ranged between 100 and 156 mAh g−1 with coulombic efficiency range between 70.9% and 93.9%.

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Interaction between Sodium Molybdate and FSWed Wled of 5083 Effected by Time

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.699.645 ◽

2013 ◽

Vol 699 ◽

pp. 645-649

Author(s):

Chang Bin Shen

Keyword(s):

Inhibition Efficiency ◽

Electrochemical Impedance ◽

Electrochemical Corrosion ◽

Sodium Molybdate ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Friction Stir ◽

Base Materials ◽

Corrosion Behaviors ◽

5083 Aluminum Alloy

Similar welds composed of 5083 were produced by friction stir welding. In the solution of 0.2 M NaHSO3 and 0.6 M NaCl, with the addition of a given concentration sodium molybdate as the inhibitor, the electrochemical corrosion behaviors of the friction stir welds (FSW) and 5083 were comparatively investigated by potentiodynamic polarization curve tests and electrochemical impedance spectra (EIS) at the ambient temperature for different test periods. The results indicated that : with the extension of period, the inhibition efficiencies (IE) for both the weld and 5083 base materials enhanced, at the same period, the inhibition efficiency (IE) for the weld was beyond that for 5083 base materials, sodium molybdate may be thought of as an effective inhibitor for 5083 aluminum alloy, the interaction between inhibitor and weld is stronger than that between inhibitor and base materials.

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