Cyclic voltammetry, electrochemical impedance and ex situ X-ray diffraction studies of electrochemical insertion and deinsertion of lithium ion into nanostructured organic–inorganic poly(3,4-ethylenedioxythiophene) based hybrids

2007 ◽  
Vol 603 (2) ◽  
pp. 287-296 ◽  
Author(s):  
A. Vadivel Murugan ◽  
M.V. Reddy ◽  
Guy Campet ◽  
K. Vijayamohanan
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Impedance ◽  
Lithium Ion ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
X Ray

A Combined Experimental and Theoretical Study of Lithiation Mechanism in ZnFe2O4 Anode Materials

MRS Advances ◽  
2018 ◽  
Vol 3 (14) ◽  
pp. 773-778 ◽  
Author(s):  
Lei Wang ◽  
Alison McCarthy ◽  
Kenneth J. Takeuchi ◽  
Esther S. Takeuchi ◽  
Amy C. Marschilok
Keyword(s):  
Early Stage ◽  
Deep Understanding ◽  
Lithium Ion ◽  
Oxidation Products ◽  
Ex Situ ◽  
Theoretical Modelling ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption

ABSTRACTZnFe2O4 (ZFO) represents a promising anode material for lithium ion batteries, but there is still a lack of deep understanding of the fundamental reduction mechanism associated with this material. In this paper, the complete visualization of reduction/oxidation products irrespective of their crystallinity was achieved experimentally through a compilation of in situ X-ray diffraction, synchrotron based powder diffraction, and ex-situ X-ray absorption fine structure data. Complementary theoretical modelling study further shed light upon the fundamental understanding of the lithiation mechanism, especially at the early stage from ZnFe2O4 up to LixZnFe2O4 (x = 2).

Electrochemical Performance Cr Doped Spinel LiMn2O4 Cathode for Lithium Ion Batteries

2014 ◽  
Vol 636 ◽  
pp. 49-53
Author(s):  
Si Qi Wen ◽  
Liang Chao Gao ◽  
Jia Li Wang ◽  
Lei Zhang ◽  
Zhi Cheng Yang ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Lithium Ion Batteries ◽  
Electrochemical Impedance ◽  
Sol Gel ◽  
Lithium Ion ◽  
Cycling Performance ◽  
Cycle Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Discharge Test

To improve the cycle performance of spinel LiMn2O4as the cathode of 4 V class lithium ion batteries, spinel were successfully prepared using the sol-gel method. The dependence of the physicochemical properties of the spinel LiCrxMn2-xO4(x=0,0.05,0.1,0.2,0.3,0.4) powders powder has been extensively investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM), charge-discharge test and electrochemical impedance spectroscopy (EIS). The results show that as Mn is replaced by Cr, the initial capacity decreases, but the cycling performance improves due to stabilization of spinel structure. Of all, the LiCr0.2Mn1.8O4has best electrochemical performance, 107.6 mAhg-1discharge capacity, 96.1% of the retention after 50 cycles.

Electrochemical performance of M3(BTC)2·12H2O (M=Co, Ni, and Zn) for Supercapacitors

2011 ◽  
Vol 15 (2) ◽  
pp. 79-82
Author(s):  
Chenmin Liao ◽  
Jiachang Zhao ◽  
Bohejin Tang ◽  
Aomin Tang ◽  
Yanhong Sun ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Impedance ◽  
Metal Organic Frameworks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scan Rate ◽  
Metal Organic ◽  
Acetate Hydrate ◽  
Xrd Patterns ◽  
Maximum Specific Capacitance

A series of Metal-Organic Frameworks (MOFs) based on 1,3,5-benzenetricarboxylic (BTC) acid and M(II) acetate hydrate (M=Co, Ni, and Zn) were successfully synthesized and named as M3(BTC)2·12H2O. These compounds were examined by X-ray diffraction (XRD) patterns. Electrochemical properties of the materials were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in 6 M KOH aqueous solutions. The maximum specific capacitance of Ni3(BTC)2·12H2O is found to be 429 F g-1 at 5 mV s-1 and 154 F g-1 at 200 mV s-1 scan rate.

scholarly journals Electrochemical and electron microscopic characterization of Super-P based cathodes for Li–O2 batteries

2013 ◽  
Vol 4 ◽  
pp. 665-670 ◽  
Author(s):  
Mario Marinaro ◽  
Santhana K Eswara Moorthy ◽  
Jörg Bernhard ◽  
Ludwig Jörissen ◽  
Margret Wohlfahrt-Mehrens ◽  
...  
Keyword(s):  
Lithium Salt ◽  
Electrochemical Impedance ◽  
Ex Situ ◽  
Cathode Side ◽  
Li Ion Batteries ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Li Ion

Aprotic rechargeable Li–O2 batteries are currently receiving considerable interest because they can possibly offer significantly higher energy densities than conventional Li-ion batteries. The electrochemical behavior of Li–O2 batteries containing bis(trifluoromethane)sulfonimide lithium salt (LiTFSI)/tetraglyme electrolyte were investigated by galvanostatic cycling and electrochemical impedance spectroscopy measurements. Ex-situ X-ray diffraction and scanning electron microscopy were used to evaluate the formation/dissolution of Li2O2 particles at the cathode side during the operation of Li–O2 cells.

Electrochemical Performance of Mg-Doped Li2FeSiO4/C as Cathode Material for Lithium-Ion Batteries

2013 ◽  
Vol 310 ◽  
pp. 90-94 ◽  
Author(s):  
Xiao Bing Huang ◽  
Hong Hui Chen ◽  
Huang Rong Li ◽  
Qian Peng Yang ◽  
Shi Biao Zhou ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Rate Capability ◽  
Lithium Ion ◽  
Impedance Spectra ◽  
X Ray Diffraction ◽  
Electrochemical Impedance Spectra ◽  
Solid State Method ◽  
X Ray ◽  
Mg Doped ◽  
Discharge Test

Li2FeSiO4/C and Li1.97Mg0.03FeSiO4/C composites were successfully prepared by a solid-state method. Both samples were systematically investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), the charge-discharge test and electrochemical impedance spectra measurement, respectively. It was found that the Li1.97Mg0.03FeSiO4/C composite exhibited an excellent rate capability with a discharge capacity of 144mAh g-1 at 0.2C and 97mAh g-1 at 5C, and after 100 cycles at 1 C, 96% of its initial capacity was retained.

Surface Modification of Spinel LiMn2O4 with Y2O3 for Lithium-Ion Battery

2011 ◽  
Vol 391-392 ◽  
pp. 1069-1074 ◽  
Author(s):  
Ying Bai ◽  
Feng Wu ◽  
Hua Tong Yang ◽  
Yu Zhong ◽  
Chuan Wu
Keyword(s):  
Surface Modification ◽  
Chemical Process ◽  
Electrochemical Impedance ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
Discharge Characteristics ◽  
X Ray ◽  
Passivating Films ◽  
Discharge Capacities ◽  
Charge Discharge

Spinel LiMn2O4was modified with Y2O3coating by a chemical process. The crystal structures of the as-prepared samples were investigated by X-ray diffraction (XRD). The charge/discharge characteristics of the modified samples were evaluated at different rates between 3.0 and 4.4V. The discharge capacities of 2.0 wt.% Y2O3-coated LiMn2O4are 116 mAh•g−1, 99.7mAh•g−1, 93.3mAh•g−1and 82.9mAh•g−1at 0.1C, 0.5C, 1C and 2C rates (at 20◦C). The cycle abilities improvement of the spinel LiMn2O4coated with Y2O3are demonstrated at elevated temperature (55◦C) and high rates (2C). From the analysis of electrochemical impedance spectroscopy (EIS), the improvement of cycle ability may be attributed to the suppression on the formation of the passivating films and the reduction of Mn dissolution, which result from the surface modification with Y2O3.

Electro-Oxidation of Ethanol on the Preparation of Electroless Ni-P Alloy Electrode

2011 ◽  
Vol 311-313 ◽  
pp. 1361-1364
Author(s):  
Shu Guang Xie ◽  
Zhan Chang Pan ◽  
Guang Hui Hu ◽  
Zhi Gang Wei ◽  
Chu Min Xiao ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Catalytic Effect ◽  
Electrochemical Impedance ◽  
Textural Properties ◽  
Alloy Electrode ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electro Oxidation ◽  
Electroless Ni ◽  
Oxidation Of Ethanol

Ni-P alloy electrode was prepared by electroless plating on the Cu-Zn substrate. The surface morphology and textural properties of electrode were characterized by Scanning electron microscope(SEM), Energy dispersive spectroscopy(EDS) and X-ray diffraction(XRD). The performance of Ni-P alloy electrode was tested by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy.The results of cyclic voltammetry showed that: At room temperature, Ni-P alloy electrode had significant catalytic effect on the electrocatalytic oxidation of ethanol in alkaline solution. Results of chronoamperometry and electrochemical impedance spectroscopy further confirmed the catalytic effect of Ni-P alloy electrode on the electrochemical oxidation of ethanol.

scholarly journals Microwave-Assisted Synthesis and Characterization of γ-MnO2 for High-Performance Supercapacitors

2021 ◽  
Author(s):  
Lorena Cuéllar-Herrera ◽  
Elsa Arce-Estrada ◽  
Antonio Romero-Serrano ◽  
José Ortiz-Landeros ◽  
Román Cabrera-Sierra ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
High Performance ◽  
Pore Diameter ◽  
Electrochemical Impedance ◽  
High Specific Capacitance ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
20 Nm

AbstractTwo hydrothermal techniques under microwave irradiation were used to synthesize γ-MnO2 from 90°C to 150°C in 10−30 min. The first technique is based on reducing KMnO4 with MnSO4, and the second one involves liquid-phase oxidation between MnSO4 and (NH4)2S2O8. The structures and morphologies of the samples were analyzed using X-ray diffraction, scanning electron microscopy, and N2 physisorption measurements. The electrochemical properties were evaluated through cyclic voltammetry and electrochemical impedance spectroscopy. The γ-MnO2 materials obtained by the first technique mainly exhibited nanorods with diameters of 40–60 nm, and the samples obtained by the second technique showed flower-like microspheres with diameters of 1−2 µm; each flower was composed of nanosheets with a thickness of 10−20 nm. The processing time directly depends on the size of the nanorods. The sample synthesized by the first technique at 150°C and 10 min has the highest specific surface area of up to 59.08 m2 g−1 and mean pore diameter of 34.11 nm. Furthermore, this sample exhibits a near-rectangular cyclic voltammetry curves and high specific capacitance of 331.3 F g−1 in 0.1 M Na2SO4 solution at 5 mV s−1 scan rate. Graphic abstract

scholarly journals Hydrothermally Synthesized Nanostructured LiMnxFe1-xPO4 (x = 0-0.3) Cathode Materials With Enhanced Properties for Lithium-Ion Batteries

2021 ◽  
Author(s):  
Dung V. Trinh ◽  
Mai T. T. Nguyen ◽  
Hue T. M. Dang ◽  
Dung T. Dang ◽  
Hang T. T. Le ◽  
...  
Keyword(s):  
Cathode Materials ◽  
Electrochemical Impedance ◽  
Lithium Ion ◽  
Slight Reduction ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
X Ray ◽  
Capacity Loss ◽  
Galvanostatic Intermittent Titration Technique ◽  
Mn Doped

Abstract Nanostructured cathode materials based on Mn-doped olivine LiMnxFe1-xPO4 (x = 0, 0.1, 0.2, and 0.3) were successfully synthesized via a hydrothermal route. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (SEM), and Raman spectroscopy indicated that the synthesized samples possessed a sphere-like nanostructure and a relatively homogeneous size distribution in the range of 100 - 200 nm. Electrochemical experiments and analysis showed that the Mn doping increased the redox potential and boosted the capacity. While the undoped olivine (LiFePO4) had a capacity of 169 mAh g-1 with a slight reduction (10%) in the initial capacity after 50 cycles (150 mAh g-1), the Mn-doped olivine samples (LiMnxFe1-xPO4) demonstrated reliable cycling tests with negligible capacity loss, reaching 151, 147, and 157 mAh g-1 for x = 0.1, 0.2, and 0.3, respectively. The results from electrochemical impedance spectroscopy (EIS) accompanied by the galvanostatic intermittent titration technique (GITT) confirmed that the Mn substitution for Fe promoted the charge transfer process and hence the rapid Li transport. These findings indicate that the LiMnxFe1-xPO4 nanostructures are promising cathode materials for lithium ion battery applications.

Sign in / Sign up

Export Citation Format

Share Document