• 한국전기화학회:학술대회논문집
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• 1999.10a
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• pp.58-58
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• 1999

• Composites Research
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• v.32 no.5
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• pp.296-300
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• 2019

Two dimensional transition metal carbides and/or nitrides, known as MXenes, are a promising electrode material in energy storage due to their excellent electrical conductivity, outstanding electrochemical performance, and abundant functional groups on the surface. Use of $Ti_3C_2$ as electrode material has significantly enhanced electrochemical performance by providing more chemically active interfaces, short ion-diffusion lengths, and improved charge transport kinetics. Here, we reports the efficient method to synthesize $Ti_3C_2$ from MAX phase, and opens new avenues for developing MXene based electrode materials for Lithium-Ion batteries.

• Journal of the Korean institute of surface engineering
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• v.57 no.3
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• pp.214-220
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• 2024

In this study, three-dimensional (3D) networks structure using single-walled carbon nanotubes (SWCNTs) for Si-graphite composite electrode was developed and studied about effects on the electrochemical performances. To investigate the effect of SWCNTs on forming a conductive 3D network structure electrode, zero-dimensional (0D) carbon black and different SWCNTs composition electrode were compared. It was found that SWCNTs formed a conductive network between nano-Si and graphite particles over the entire area without aggregation. The formation of 3D network structure enabled to effective access for lithium ions leading to improve the c-rate performance, and provided cycle stability by alleviating the Si volume expansion from flexibility and buffer space. The results of this study are expected to be applicable to the electrode design for high-capacity lithium-ion batteries.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.540-543
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• 2000

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li polymer battery. The temperature dependence of conductivity, impedance spectroscopy and electrochemical properties of PAN/PVDF electrolytes as a function of a mixed ratio were reported for PAN/PVDF based polymer electrolyte films, which were prepared by thermal gellification method of preweighed PAN/PVDF, plasticizer and Li salt. The conductivity of PAN/PVDF electrolytes was $10^{-3}$S/cm. $PAN_{10}$$PVDF_{10}$$LiClO_4$$PC_{5}$$EC_{5}$ electrolyte has the better conductivity compared to others. The interfacial resistance behavior between the lithium electrode and PAN/PVDF based polymer electrolyte has also been investigated and compare with that between the lithium electrode and the PAN/PVDF based polymer electrolyte.

• Journal of the Korean Applied Science and Technology
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• v.20 no.2
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• pp.130-140
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• 2003

In order to improve the lithium ion battery's performance, the carbon nanofibers were introduced to the anode electrode fabricated with natural graphite particles. The influence of structural adjustment of the particles by the introduction method of carbon nanofibers and the content of carbon nanofibers on the electrical property and charge/discharge characteristics of the electrode were investigated. The electrode fabricated with the mixture of 10 wt% of carbon nanofibers grown separately and 90 wt% of graphite particles showed an excellent discharge capacity of 400 mAh/g and the improved cycle performance. The improved performance could be explained by that the carbon nanofibers shortened and uniformly distributed on the surface of graphite particles by ball milling increased the stability for the intercalation/deintercalation of lithium ion and increased the electrical conductivity due to the closed packing between graphite particles.

• Ceramist
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• v.21 no.4
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• pp.406-415
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• 2018

Lithium ion batteries have been widely adopted as energy storage and the LIB global market has grown fastest. However, LIB players have struggled against maximizing energy density since commercial monolithic electrodes are limited by electrolyte depletion caused by long and tortuous Li-ion diffusion pathways. Recently, new strategies designing the structure of battery electrodes strive for creating fast Li-ion path and alleviating electrolyte depletion problem in monolithic electrodes. In this paper, given the fundamental and experimental approaches, we compare the monolithic to structured electrodes and demonstrate the ways to fabricate high energy, fast chargeable Lithium ion battery.

• Journal of the Korean Electrochemical Society
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• v.5 no.2
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• pp.52-56
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• 2002

Tin oxide was coated on graphite particle by sol-gel method and an electrode with this material having microcrystalline structure for lithium ion battery was obtained by heat treatment in the range $400-600^{\circ}C$. The content of tin oxide was controlled within the range of $2.25wt\%\~11.1wt\%$. The discharge capacity increased with the content of tin oxide and also initial irreversible capacity increased. The discharge capacity of tin oxide electrode showed more than 350 mAh/g at the initial cycle and 300 mAh/g after the 30th cycle in propylene carbonate(PC) based electrolyte whereas graphite electrode without surface modification showed 140 mAh/g. When the charge and discharge rate was changed from C/5 to C/2, The discharge capacity of tin oxide and graphite electrode showed $92\%\;and\;77\%$ of initial capacity, respectively. It has been considered that such an enhancement of electrode characteristics was caused because lithium $oxide(Li_2O)$ passive film formed from the reaction between tin oxide and lithium ion prevented the exfoliation of graphite electrode and also reduced tin enhanced the electrical conduction between graphite particles to improve the current distribution of electrode.

• Journal of Electrochemical Science and Technology
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• v.2 no.1
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• pp.8-13
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• 2011

Interfacial compatibility between the Si-Cu electrode and diluted ionic liquid electrolyte containing 50 vol.% of 1M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/1-methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide (MPP-TFSI) and 50 vol.% dimethyl carbonate (DMC) in a lithium cell and dilution effect on surface chemistry are examined. ex-situ ATR FTIR analysis results reveal that the surface of the Si-Cu electrode cycled in the diluted ionic liquid electrolyte is effectively passivated with the SEI layer mainly composed of carboxylate salts-containing polymeric compounds produced by the decomposition of DMC. Surface species by the decomposition of TFSI anion and MPP cation are found to be relatively in a very low concentration level. Passivation of electrode surface with the SEI species contributes to protect from further interfacial reactions and to preserve the electrode structure over 200 cycles, delivering discharge capacity of > 1670 $mAhg^{-1}$ and capacity retention of 88% of maximum discharge capacity.

• Journal of the Korean Electrochemical Society
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• v.23 no.2
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• pp.47-55
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• 2020

Highly loaded LiCoO₂ positive electrodes are prepared to construct high-energy density lithium-ion batteries, their electrochemical performances are evaluated. For the standard electrode, a loading of about 2.2 mAh/㎠ is used, and for a high-loading electrode, an electrode is manufactured with a loading level of about 4.4 mAh/㎠. The content of carbon black as electronic conducting additive, and the porosity of the electrode are configured differently to compare the effects of electron conduction and ionic conduction in the highly loaded LiCoO₂ electrode. It is expected that the electrochemical performance is improved as the amount of the carbon black increases, but the specific capacity of the LiCoO₂ electrode containing 7.5 weight% carbon black is rather reduced. When the conductive material is excessively provided, an increase of electrode thickness by the low content of the LiCoO₂ active material in the same loading level of the electrode is predicted as a cause of polarization growth. When the electrode porosity increases, the path of ionic transport can be extended, but the electron conduction within the electrode is disadvantageous because the contact between the active material and the carbon black particles decreases. As the electrode porosity is lowered through the sufficient calendaring of the electrode, the electrochemical performance is improved because of the better contact between particles in the electrode and the reduced electrode thickness. In the electrode design for the high-loading, it is very important to construct the path of electron conduction as well as the ion transfer and to reduce the electrode thickness.

• Carbon letters
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• v.3 no.1
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• pp.17-24
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• 2002

The electrochemical behavior of the $LiCoO_2$ electrode, containing carbon black as a conductor, depends upon the nature and characteristics of carbon black. In this study, six different kinds of carbon blacks were employed to investigate the relationship between the properties of carbon blacks and electrochemical characteristics of the electrode. The larger amount of surface oxygen functional groups brought the lower electrical conductivity for the carbon blacks. The electrical conductivity of carbon blacks was closely related to the impurities such as ash and volatile content. The rate capability and cyclability of the electrode were improved with the higher conductivity of carbon blacks used. So, it can be concluded that high conductive carbon black plays an important role as a conductor for high rate of charge-discharge capability and initial efficiency.