Galvanostatic charge–discharge tests, 57Fe and 119Sn Mössbauer and XRD measurements on novel Sn-Ni-Fe electrodeposits

Li0.95Na0.05Ti2(PO4)3/C nanocomposite was prepared by sol-gel method.The structure and morphology of the samples were characterized by XRD, SEM which showed the particles had typical NASICON structure and diameter range from 400~500nm. The electrochemical performance were tested by cyclic voltammetry and galvanostatic charge–discharge. Results show Li0.95Na0.05Ti2(PO4)3/C nanocomposite exhibitsmuch better electrochemical performance than bare Li0.95Na0.05Ti2(PO4)3.

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Preparation and Electrochemical Properties of LaMnO3 Powder as a Supercapacitor Electrode Material

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.698 ◽

2017 ◽

Vol 727 ◽

pp. 698-704 ◽

Cited By ~ 3

Author(s):

Xian Wei Wang ◽

Xiao Er Wang ◽

Hui Chao Zhang ◽

Qian Qian Zhu ◽

Dong Li Zheng ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Electrochemical Properties ◽

Electrode Material ◽

Raw Materials ◽

Sol Gel ◽

Galvanostatic Charge ◽

Supercapacitor Electrode ◽

Lanthanum Manganate ◽

Pure Phase ◽

Charge Discharge

The structural and electrochemical properties of lanthanum manganate (LaMnO3) powder prepared by the sol-gel method are researched in this article. The powder calcined at 600 °C showed amorphous, and the powder calcined at 700-800 °C showed the pure phase of the LaMnO3. The grains with the size of about 80-120 nm were agglomerating together. Cyclic voltammetry and galvanostatic charge-discharge were used to characterize the electrochemical properties in alkaline environment. The electrochemical properties calcined at 700 °C showed a specific capacitance of 73 F/g at the current density of 0.5 A/g. The raw materials for preparing the LaMnO3 powder are cheap, and the operation method is simple.

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High Rate Charge/Discharge Characteristics in Composite Film of Mesoporous TiO2 and Polyaniline for Photorechargeable Battery

MRS Proceedings ◽

10.1557/opl.2014.335 ◽

2014 ◽

Vol 1606 ◽

Cited By ~ 1

Author(s):

Teruaki Nomiyama ◽

Kenta Sakamoto ◽

Tomohito Yoshida ◽

Akinori Kagiyama ◽

Yuji Horie

Keyword(s):

Composite Film ◽

High Performance ◽

Specific Capacity ◽

Electrical Energy ◽

High Rate ◽

Galvanostatic Charge ◽

Discharge Characteristics ◽

Electrical Energy Storage ◽

Charging Rate ◽

Charge Discharge

ABSTRACTOne of promising photorechargeable electrode, which has two functions of photovoltaic and electrical energy storage, is a composite film of mesoporous TiO2 and conducting polymer polyaniline. Galvanostatic charge/discharge characteristics of the TiO2-polyaniline composite were examined to reveal how fast the film was charged. The film with a specific capacity 60-120 mAh g–1 was found to be fully charged at high charging rate 20 mA cm–2 which is comparable to high performance solar cells. Such high charging rate was achieved by the compact polyaniline layer covering the large specific surface area of mesoporous TiO2 film.

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Influence of Heating Temperature on Structure, Morphology and Electrochemical Performance of LiV3O8 Cathode for Lithium-Ion Batteries Application

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1010.314 ◽

2020 ◽

Vol 1010 ◽

pp. 314-320

Author(s):

Mohamad Izha Ishak ◽

Khairel Rafezi Ahmad ◽

Rozana A.M. Osman ◽

Mohd Sobri Idris

Keyword(s):

Electrochemical Performance ◽

Lithium Ion Batteries ◽

Layered Structure ◽

Heating Temperature ◽

Lithium Ion ◽

Galvanostatic Charge ◽

Heat Treated ◽

Structure Morphology ◽

Performance Results ◽

Charge Discharge

LiV3O8 layered structure was successfully synthesized by a conventional solid-state approach and subsequent heat-treated at 400, 450, 500 and 550 oC. The samples were characterized by XRD, SEM, TEM, BET. Electrochemical performance of LiV3O8 was investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge. The results showed that high purity of LiV3O8 with layered structure was formed. The morphology of the samples were mixed between nanorods and nanosheets structure. For electrochemical performance, results showed that LiV3O8 heat-treated at 500 oC performed a highest charge and discharge capacity of 212 and 172 mAh g-1, respectively. From electrochemical performance results made them a good candidate for cathode material for lithium-ion batteries application.

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How to Measure and Calculate Equivalent Series Resistance of Electric Double-Layer Capacitors

Molecules ◽

10.3390/molecules24081452 ◽

2019 ◽

Vol 24 (8) ◽

pp. 1452 ◽

Cited By ~ 9

Author(s):

Rafael Vicentini ◽

Leonardo Morais Da Silva ◽

Edson Pedro Cecilio Junior ◽

Thayane Almeida Alves ◽

Willian Gonçalves Nunes ◽

...

Keyword(s):

Double Layer ◽

Electric Double Layer ◽

Series Resistance ◽

Voltage Drop ◽

Equivalent Series Resistance ◽

Galvanostatic Charge ◽

Applied Current ◽

Double Layer Capacitors ◽

Charge Discharge ◽

Electric Double Layer Capacitors

Electric double-layer capacitors (EDLCs) are energy storage devices that have attracted attention from the scientific community due to their high specific power storage capabilities. The standard method for determining the maximum power (Pmax) of these devices uses the relation Pmax = U2/4RESR, where U stands for the cell voltage and RESR for the equivalent series resistance. Despite the relevance of RESR, one can observe a lack of consensus in the literature regarding the determination of this parameter from the galvanostatic charge-discharge findings. In addition, a literature survey revealed that roughly half of the scientific papers have calculated the RESR values using the electrochemical impedance spectroscopy (EIS) technique, while the other half used the galvanostatic charge discharge (GCD) method. RESR values extracted from EIS at high frequencies (>10 kHz) do not depend on the particular equivalent circuit model. However, the conventional GCD method better resembles the real situation of the device operation, and thus its use is of paramount importance for practical purposes. In the latter case, the voltage drop (ΔU) verified at the charge-discharge transition for a given applied current (I) is used in conjunction with Ohm’s law to obtain the RESR (e.g., RESR = ΔU/ΔI). However, several papers have caused a great confusion in the literature considering only applied current (I). In order to shed light on this important subject, we report in this work a rational analysis regarding the GCD method in order to prove that to obtain reliable RESR values the voltage drop must be normalized by a factor of two (e.g., RESR = ΔU/2I).

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The Use of Succinonitrile as an Electrolyte Additive for Composite-Fiber Membranes in Lithium-Ion Batteries

Membranes ◽

10.3390/membranes10030045 ◽

2020 ◽

Vol 10 (3) ◽

pp. 45 ◽

Cited By ~ 2

Author(s):

Jahaziel Villarreal ◽

Roberto Orrostieta Chavez ◽

Sujay A. Chopade ◽

Timothy P. Lodge ◽

Mataz Alcoutlabi

Keyword(s):

Ionic Liquid ◽

Ionic Conductivity ◽

Lithium Ion Batteries ◽

Specific Capacity ◽

Lithium Ion ◽

Composite Fiber ◽

Galvanostatic Charge ◽

Lithium Anode ◽

Charge Discharge ◽

Licoo2 Cathode

In the present work, the effect of temperature and additives on the ionic conductivity of mixed organic/ionic liquid electrolytes (MOILEs) was investigated by conducting galvanostatic charge/discharge and ionic conductivity experiments. The mixed electrolyte is based on the ionic liquid (IL) (EMI/TFSI/LiTFSI) and organic solvents EC/DMC (1:1 v/v). The effect of electrolyte type on the electrochemical performance of a LiCoO2 cathode and a SnO2/C composite anode in lithium anode (or cathode) half-cells was also investigated. The results demonstrated that the addition of 5 wt.% succinonitrile (SN) resulted in enhanced ionic conductivity of a 60% EMI-TFSI 40% EC/DMC MOILE from ~14 mS·cm−1 to ~26 mS·cm−1 at room temperature. Additionally, at a temperature of 100 °C, an increase in ionic conductivity from ~38 to ~69 mS·cm−1 was observed for the MOILE with 5 wt% SN. The improvement in the ionic conductivity is attributed to the high polarity of SN and its ability to dissolve various types of salts such as LiTFSI. The galvanostatic charge/discharge results showed that the LiCoO2 cathode with the MOILE (without SN) exhibited a 39% specific capacity loss at the 50th cycle while the LiCoO2 cathode in the MOILE with 5 wt.% SN showed a decrease in specific capacity of only 14%. The addition of 5 wt.% SN to the MOILE with a SnO2/C composite-fiber anode resulted in improved cycling performance and rate capability of the SnO2/C composite-membrane anode in lithium anode half-cells. Based on the results reported in this work, a new avenue and promising outcome for the future use of MOILEs with SN in lithium-ion batteries (LIBs) can be opened.

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Effect of Synthesis Conditions on Pseudocapacitance Properties of Nitrogen-Doped Porous Carbon Materials

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.59.112 ◽

2019 ◽

Vol 59 ◽

pp. 112-125

Author(s):

Volodymyr Boichuk ◽

Volodymyr Kotsyubynsky ◽

Andrii Kachmar ◽

Sergiy Budzulyak ◽

Ivan Budzulyak ◽

...

Keyword(s):

Carbon Materials ◽

Aqueous Electrolyte ◽

Electrochemical Impedance ◽

Galvanostatic Charge ◽

Discharge Data ◽

Synthesis Conditions ◽

Capacitive Properties ◽

Charge Discharge ◽

Redox Capacitance

The electrochemical properties of the nitrogen-enriched carbons obtained by plant raw treatment as electrode material for supercapacitors were investigated by electrochemical impedance spectroscopy, cycling voltammetry and galvanostatic charge-discharge cycling in KOH aqueous electrolyte. The effect of activation agent (NaOH) concentration and carbonization temperature were analyzed. The separation of double layer and redox capacitance components was done. The dominating role of microporosity for capacitive properties was demonstrated. The capacitance of model capacitors based on carbons obtained at different modes was calculated from both from cycling voltammetry and galvanostatic charge-discharge data. The maximal values of specific capacitance of carbon materials carbonized at 600°C and 900°C are about 100 and 120 F/g, respectively.

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Electrochemical behavior of Bi4B2O9towards lithium-reversible conversion reactions without nanosizing

Physical Chemistry Chemical Physics ◽

10.1039/c7cp07693b ◽

2018 ◽

Vol 20 (4) ◽

pp. 2330-2338 ◽

Cited By ~ 5

Author(s):

Florian Strauss ◽

Gwenaëlle Rousse ◽

Dmitry Batuk ◽

Mingxue Tang ◽

Elodie Salager ◽

...

Keyword(s):

Electrochemical Behavior ◽

Galvanostatic Charge ◽

Conversion Reaction ◽

Voltage Hysteresis ◽

Small Voltage ◽

Charge Discharge ◽

Discharge Curves

Galvanostatic charge–discharge curves for a Bi4B2O9/C macrocomposite, highlighting the small voltage hysteresis for the conversion reaction around 300 mV.

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Influence of Separator Thickness on the Performance of Electric Double Layer Supercapacitors in Aqueous Electrolyte

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1012.109 ◽

2020 ◽

Vol 1012 ◽

pp. 109-113

Author(s):

D.V. Silva ◽

G.S. Galdino ◽

Lusinete Pereira Barbosa ◽

J.C.S. Casini ◽

R.N. Faria

Keyword(s):

Electric Double Layer ◽

Room Temperature ◽

Aqueous Electrolyte ◽

Carbon Electrodes ◽

Galvanostatic Charge ◽

Homogeneous Microstructure ◽

X Ray ◽

Morphological Evaluation ◽

Charge Discharge ◽

Discharge Curves

The effects of the separator thickness (δ) upon the equivalent series resistances (ESR) and specific capacitances (Cs) of supercapacitors electrodes have been investigated using commercially available porous filter paper (δ=150 μm, pores size=7.5 μm, 80 gm-2). Commercial activated carbon electrodes immersed in 1molL-1 KOH electrolyte (25°C) have been employed in this study. The specific capacitances were calculated from cyclic voltammetry curves at room temperature employing various scan rates (5, 10, 15 and 30 mVs-1). Internal series resistances of the supercapacitors were measured using the galvanostatic charge discharge curves also at room temperature. A maximum of 28 separators (δ=4200 μm) have been employed in this investigation. It has been shown that the ESR increases substantially with separator thickness (from 3.1 to 7.9 Ωcm2). The specific capacitance decreased somewhat with increasing separator thickness and scan rates (from 64 to 52 Fg-1; at 5 mVs-1). The microstructures of the electrode material have been investigated using scanning electron microscopy (SEM) and chemical microanalyses employing energy dispersive X-ray analysis (EDX). A compositional and morphological evaluation of these electrodes showed a very homogeneous microstructure.

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Template Synthesis of Activated Carbon for Supercapacitor

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.568 ◽

2010 ◽

Vol 663-665 ◽

pp. 568-571

Author(s):

Ren Qing Wang ◽

Qin Fang ◽

Mei Gen Deng

Keyword(s):

Cyclic Voltammetry ◽

Activated Carbon ◽

Phenolic Resin ◽

Tween 80 ◽

Galvanostatic Charge ◽

N2 Adsorption ◽

Power Property ◽

Capacitance Characteristics ◽

A Current ◽

Charge Discharge

Activated carbon was fabricated by using phenolic resin as carbon source, tween-80 as organic template, KOH as activator. The samples were analyzed by N2 adsorption, scanning electron microscopy (SEM). Cyclic voltammetry and galvanostatic charge-discharge were used to characterize the electrochemical performance of the samples. The results showed that specific surface area of the prepared sample was 1935.99 m2/g, pore size was mainly in the range of 1.0～4.0 nm and showed typical capacitance characteristics in cyclic voltammetry. At a current density of 15mA/cm2, a specific capacitance of 246.18F/g was achieved and the resistance was 1.11Ω. Supercapacitors based on the sample had low ESR and excellent power property.

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