• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1059-1064
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• 1998

We have investigated various kind of graphite and MCMB6-28 to develop carbon negative electrode for lithium ion secondary battery. The interlayer length of them was $3.358{\sim}3.363{\AA}$ and the BET specific surface area was $2.95{\sim}26.15m^2/g$. From this study, When the interlayer of them was large and the BET specific surface area was high, the electrochemical characteristics of them was very excellent. Adding 0, 3, 5, wt% of KJ-Black as conducting agent to various graphitic carbon active materials, interface resistance of electrode and electrolyte was less, but rechargeability was better at 3 wt%. At constant current charge and discharge test, discharge capacity was small according to large current.

• Journal of the Korean Ceramic Society
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• v.47 no.6
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• pp.638-642
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• 2010

The spinel material $Li_4Ti_5O_{12}$ has attracted considerable attention as an anode electrode material for many battery applications owing to its light weight and high energy density. However, the real capacity of $Li_4Ti_5O_{12}$ powder as determined by the solid-state method is lower than the ideal capacity. In this study, we investigated the effect of the dopants in M-doped spinel $Ba_xLi_{4-2x}Ti_5O_{12}$(x=0.005, 0.05, 0.1) powders prepared by the solid-state reaction method and used as the anode material in lithiumion batteries. The results confirmed the effect of the Ba and Sr dopants on the powder properties of the spinel $Li_4Ti_5O_{12}$, which exhibited a pure spinel structure without any secondary phase in its XRD pattern. Moreover, the electrochemical properties of the spinel M-LTO materials were investigated using a half cell. The electrochemical data show that cells with anodes made of undoped $Li_4Ti_5O_{12}$ and Ba- and Sr-doped $Li_4Ti_5O_{12}$ have discharge capacities of 97, 130, and 112 mAh/g, respectively, at the first cycle. Moreover, the Ba- and Sr-doped spinel $Li_4Ti_5O_{12}$ demonstrated good properties in the mid-voltage range at 1.55 V, showing stable cyclic voltammogram properties which surpassed those of the same material without Ba or Sr at 1 C after 100 cycles.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.11
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• pp.1049-1054
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• 1998

The LiCo$O_2$ powder was synthesized by a solution phase reaction. This shows a high (003) peak intensity and low (104) or (101) peak intensities in X-ray diffraction spectra. The LiCo$O_2$/Li cell shows an initial discharge capacity of 102.9mAh/g and an average discharge potential or 3.877V at a current density of 50mA/g between 3.0~4.2V. The peaks of dQ/dV plot are associated with Li ion intercalation/deintercalation reaction. To evaluate the cycleability of an actual battery system, cylindrical lithium ion cell was manufactured using graphitized MPCF anode and LiCoO$_2$ cathode. After 100th cycle, this cel maintains 80% capacity of 10th cycle value. The LiCoO$_2$/MPCF cell has a high discharge voltage of 3.6~3.7V and a good cycle life performance on cycling between 4.2~2.7V.

• Carbon letters
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• v.27
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• pp.98-107
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• 2018

Free-standing electrodes of CuO nanorods in carbon nanotubes (CNTs) are developed by synthesizing porous CuO nanorods throughout CNT webs. The electrochemical performance of the free-standing electrodes is evaluated for their use in flexible lithium ion batteries (LIBs). The electrodes comprising CuO@CNT nanocomposites (NCs) were characterized by charge-discharge testing, cyclic voltammetry, and impedance measurement. These structures are capable of accommodating a high number of lithium ions as well as increasing stability; thus, an increase of capacity in long-term cycling and a good rate capability is achieved. We demonstrate a simple process of fabricating free-standing electrodes of CuO@CNT NCs that can be utilized in flexible LIBs with high performance in terms of capacity and cycling stability.

• Journal of Adhesion and Interface
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• v.24 no.1
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• pp.9-16
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• 2023

Silicon has been studied as an anode material for next-generation lithium ion batteries due to its high theoretical electrochemical capacity. However, the extreme volume change during the lithiation/delithiation and the inherently low electronic conductivity of silicon hamper the practical application of silicon anodes. Conductive polymer binders are effective means to solve these problems, and it has been reported that the performance of the silicon anode can be greatly improved through the proper molecular design of the conductive polymer binders. In this paper, representative recent studies on conductive polymer binders for silicon anodes will be introduced, and through this, binder design strategies to overcome the limitations of silicon anodes will be explored.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.5
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• pp.335-340
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• 2018

Transition metal oxide materials have attracted widespread attention as Li-ion battery electrode materials owing to their high theoretical capacity and good Li storage capability, in addition to various nanostructured materials. Here, we fabricated a CoO Li-ion battery in which Co nanoparticles (NPs) are deposited into a current collector through electrophoretic deposition (EPD) without binding and conductive agents, enabling us to focus on the intrinsic electrochemical properties of CoO during the conversion reaction. Through optimized Co NP synthesis and electrophoretic deposition (EPD), CoO Li-ion battery with 630 mAh/g was fabricated with high cycle stability, which can potentially be used as a test platform for a fundamental understanding of conversion reaction.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.241-246
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• 1999

In this research, electrokinetic remediation test was experimented with contaminated kaoline specimen at below, above the cation-exchange capacity of the mineral. The changes of the flow in electro-osmosis with open electrodes and current were presented, and lead removal results were evaluated through the extraction test. As a result, it was showed that removal efficiency was 20-30%, 67-87% In the anode As lead transport continues, the lead precipitation within a narrow zone very close to the cathode can go significantly high. This high lead precipitation near the cathode could block the flow path, decrease the conductivity, and thus the electroosmotic flow. The net effect will cause a decrease in the efficiency of electrokinetic processing. Therefore, in this study, citric acid and surfactant solution was used at the cathode as enhancement techniques.

• Journal of the Korean Electrochemical Society
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• v.16 no.2
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• pp.81-84
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• 2013

We demonstrate rutile $TiO_2$ branched nanostructure ($TiO_2$-BN) electrodes synthesized by seeding method for enhanced lithium intercalation properties. The morphology and crystalline nature of the $TiO_2$-BN were clearly observed by field-emission transmission electron microscopy and fast Fourier transform pattern. The $TiO_2$-BN electrodes showed excellent capacity and high rate performance. The improved lithium-ion intercalation properties of the $TiO_2$- BN may be attributed to relatively large specific surface area and short transport distance of the branched nanostructure.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.319-322
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• 2009

Gel polymer electrolytes were prepared by immersing a porous poly(vinylidene fluoride-co-hexafluoropropylene) membrane in an electrolyte solution containing small amounts of polymerizable additive (3,4-ethylenedioxythiophene, thiophene, biphenyl). The organic additives were electrochemically oxidized to form conductive polymer films on the electrode at high potential. With the gel polymer electrolytes containing different organic additive, lithium-ion polymer cells composed of carbon anode and LiCo$O_2$ cathode were assembled and their cycling performances were evaluated. Adding small amounts of thiophene or 3,4-ethylenedioxythiophene to the gel polymer electrolyte was found to reduce the charge transfer resistance in the cell and it thus exhibited less capacity fading and better high rate performance.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.384-391
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• 2020

Due to its characteristics of light weight, high energy density, good safety, long service life, no memory effect, and environmental friendliness, lithium-ion batteries (LIBs) are widely used in various portable electronic products. The capacity and performance of LIBs largely depend on the performance of electrode materials. Therefore, the development of better positive and negative materials is the focus of current research. The application of metal organic framework materials (MOFs) derivatives in energy storage has attracted much attention and research. Using MOFs as precursors, porous metal oxides and porous carbon materials with controllable structure can be obtained. In this paper, rod-shaped Co-MOF-74 was grown on Ni Foam (NF) by hydrothermal method, and then Co-MOF-74/NF precursor was heat-treated to obtain rodshaped Co₃O₄/NF. Ni Foam was skeleton structured, which effectively relieved. The change of internal stress changes and destroys the structural volume of the electrode material and reduces the capacity attenuation. Co₃O₄/NF composite material has a specific discharge capacity of up to 1858 mA h/g for the first time, and a reversible capacity of up to 902.4 mA h/g at a current density of 200 mA/g, and has excellent rate and impedance performance. The synthesis strategy reported in this article opens the way to design high-performance electrodes for energy storage and electrochemical catalysis.