Electrochemical Properties of Carbon-Coated NbO2 as a Negative Electrode for Lithium-Ion Batteries

We investigated the electrochemical properties of carbon-coated niobium dioxide (NbO2) as a negative electrode material for lithium-ion batteries. Carbon-coated NbO2 powders were synthesized by ball-milling using carbon nanotubes as the carbon source. The carbon-coated NbO2 samples were of smaller particle size compared to the pristine NbO2 samples. The carbon layers were coated non-uniformly on the NbO2 surface. The X-ray diffraction patterns confirmed that the inter-layer distances increased after carbon coating by ball-milling. This lead to decreased charge-transfer resistance, confirmed by electrochemical impedance spectroscopy, allowing electrons and lithium-ions to quickly transfer between the active material and electrolyte. Electrochemical performance, including capacity and initial coulombic efficiency, was therefore improved by carbon coating by ball-milling.

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Electrochemical Properties of Chemically Etched-NbO2 as a Negative Electrode Material for Lithium Ion Batteries

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.115 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 115-118 ◽

Cited By ~ 3

Author(s):

Yong Hoon Cho ◽

Soon Ki Jeong ◽

Yang Soo Kim

Keyword(s):

Electrochemical Properties ◽

Lithium Ion Batteries ◽

Electrode Material ◽

Photoelectron Spectroscopy ◽

Active Material ◽

Negative Electrode ◽

Lithium Ion ◽

Electrode Performance ◽

Niobium Dioxide ◽

Negative Electrode Material

The electrochemical properties niobium dioxide (NbO2) was investigated as a negative electrode material for lithium ion batteries. The NbO2electrode showed a large irreversible capacity and small discharge capacity. The results of X-ray photoelectron spectroscopy indicate that the poor electrode performance of NbO2may be caused by niobium pentoxide (Nb2O5) formed on the surface of active material. The Nb2O5could be removed by chemical etching to some extent, thus improving the electrode performance.

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Electrochemical Decomposition of Poly(Vinylidene Fluoride) Binder for a Graphite Negative Electrode in Lithium-Ion Batteries

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.127 ◽

2017 ◽

Vol 893 ◽

pp. 127-131 ◽

Cited By ~ 1

Author(s):

Min Ji Kim ◽

Chang Hee Lee ◽

Mun Hui Jo ◽

Soon Ki Jeong

Keyword(s):

Lithium Ion Batteries ◽

Vinylidene Fluoride ◽

Electrochemical Impedance ◽

Negative Electrode ◽

Reduction Process ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Electrode Resistance ◽

Poly Vinylidene Fluoride

To clarify the electrochemical decomposition of poly (vinylidene fluoride) (PVdF) used as a binder for lithium-ion batteries while simultaneously verifying the correlation between electrode resistance and the PVdF content in graphite negative electrodes, in this study, we applied lithium bis (trifluoromethanesulfonyl) imide, which suppresses graphite exfoliation, as a salt. As a result, the electrochemical decomposition of PVdF was observed at a higher potential than that at which the electrolyte was decomposed during the reduction process. Additionally, this study demonstrated (through electrochemical impedance spectroscopy analysis) that electrode resistances such as solid electrolyte interface and charge transfer resistance proportionally increased with the PVdF content.

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Enhancing the performance of Li3VO4 by combining nanotechnology and surface carbon coating for lithium ion batteries

Journal of Materials Chemistry A ◽

10.1039/c5ta02094h ◽

2015 ◽

Vol 3 (21) ◽

pp. 11253-11260 ◽

Cited By ~ 39

Author(s):

Gaoqi Shao ◽

Lin Gan ◽

Ying Ma ◽

Huiqiao Li ◽

Tianyou Zhai

Keyword(s):

Lithium Ion Batteries ◽

Ball Milling ◽

Carbon Coating ◽

Coulombic Efficiency ◽

Specific Capacity ◽

Lithium Ion ◽

Surface Carbon ◽

Conductive Additive ◽

Carbon Coated ◽

Coating Layers

Carbon-coated nanosized Li3VO4 was successfully obtained by combination of ball milling and CVD techniques. The thin and full coating layers of carbon can greatly decrease the amount of conductive additive in the electrode and enhance the first coulombic efficiency, specific capacity and rate performances of Li3VO4.

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Electrochemical Properties of NbO as a Negative Electrode Material for Lithium Secondary Batteries

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.835.126 ◽

2016 ◽

Vol 835 ◽

pp. 126-130 ◽

Cited By ~ 1

Author(s):

Kyoung Soo Park ◽

Soon Ki Jeong ◽

Yang Soo Kim

Keyword(s):

Electrochemical Properties ◽

Ball Milling ◽

Electrode Material ◽

Negative Electrode ◽

Lithium Ion ◽

Reversible Capacity ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Lithium Secondary Batteries ◽

Negative Electrode Material

The electrochemical properties of niobium monoxide, NbO, were investigated as a negative electrode material for lithium-ion batteries. Lithium ions were inserted into and extracted from NbO material at potentials < 1.0 V versus Li/Li+, involving formation of a solid electrolyte interface (SEI) on the NbO surface in the first cycle. Its reversible capacity is ~67 mAh g–1 with the capacity retention of ~109% after 50 cycles. The magnitude of charge transfer resistance was greatly decreased by ball-milling the pristine NbO, whereas the ball-milling had no effect on the SEI resistance.

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