Songgang-dong, South Korea
Songgang-dong, South Korea

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Hossain M.M.,Kyungpook National University | Faisal S.N.,Kyungpook National University | Kim C.S.,Pohang University of Science and Technology | Cha H.J.,Pohang University of Science and Technology | And 2 more authors.
Electrochemistry Communications | Year: 2011

A novel strip-based disposable amperometric proton sensor that can selectively detect organophosphate neurotoxins (i.e., paraoxon) is described. The detection methodology is based on measuring the current change involved in the assisted proton transfer by a proton selective ligand (e.g., ETH 1778) across a microelliptic hole interface between the aqueous and polyvinylchloride-2-nitrophenyloctylether gel phase. The selective detection of paraoxon is achieved by measuring protons released by the specific hydrolysis of paraoxon with the organophosphorus hydrolase enzyme. A two-step process involving the hydrolysis and proton transfer reaction was characterized using cyclic voltammetry and differential pulse stripping voltammetry. A strip-based sensor fabricated using a simple polydimethylsiloxane (PDMS) mold with the resulting device was found to exhibit a linear response over a wide range of paraoxon concentrations (0.5 μM-100 μM) present in aqueous samples. In addition to the excellent detection limit and a wide dynamic range, a superb selectivity in the presence of common interfering agents in agricultural samples is achieved. © 2011 Elsevier B.V. All Rights Reserved.


Song S.-W.,Chungnam National University | Choi H.,Chungnam National University | Park H.Y.,GS Nanotech Co. | Park G.B.,GS Nanotech Co. | And 2 more authors.
Journal of Power Sources | Year: 2010

An investigation is made of the high-rate capability (up to 10 C) of all-solid-state thin-film lithium batteries that comprise of Li/LiPON/LiCoO 2 on a flexible substrate, as well as of the effect of high-rate cycling on the structure of these batteries. Raman spectroscopic analysis results reveal that an increase in the rate promotes film orientation of the LiCoO2 cathode with (1 0 1)/(1 0 4) planes and limited lithium intercalation and deintercalation within the layered hexagonal structure without a phase transition to monoclinic. Although with high-rate cycling the LiCoO2 columnar grains tend to aggregate and lose grain orientation, as observed by scanning electron microscopic imaging, the film morphology is efficiently preserved when there is exterior multilayered encapsulation on thin-film batteries. Encapsulated thin-film batteries at 10 C show excellent capacity retention of 95% over 800 cycles, delivering > 22 μAh cm -2 μm-1. The data contribute to a basic understanding of the structure-rate performance relationship of all-solid-state battery systems. © 2010 Elsevier B.V. All rights reserved.


Yoon Y.S.,Yonsei University | Cho S.B.,Agency for Defense Development | Nam S.C.,GS NanoTech Co.
Electrochimica Acta | Year: 2012

A module with 11 thin film battery (TFB) stacks was fabricated to investigate its internal resistance and charging characteristics to a real capacitor with 150 uF. Each cell consisted of thin layers of LiCoO 2, LiPON and Li on a ceramic substrate, and each layer was deposited by radio frequency (RF) + direct current (DC) hybrid magnetron sputtering, RF reactive sputtering, and thermal evaporation, respectively. In order to increase the effective surface area of the TFB in a limited small volume, 11 cells were stacked and connected in parallel. By designing the thermal switch with a heating source, its capacitor charging performance was well maintained, even at temperatures below -30 °C, as well as at room temperature. Charging to greater than 4 V was completed within 0.06 sec at room temperature and within 0.13 s at -30 ° C due to the heat-up process. A novel battery system consisting of the TFB module with a thermal switch and a heating source proved to be a promising substitute for the ampoule type reserve battery in small sized electrical fuses, even at very low temperatures. © 2012 Elsevier Ltd. All rights reserved.


Yoon Y.S.,Yonsei University | Lee S.H.,Yonsei University | Cho S.B.,Agency for Defense Development | Nam S.C.,GS Nanotech Co.
Journal of the Electrochemical Society | Year: 2011

A crack-free LiCoO2 thin film with a preferred oriented crystalline structure is obtained by adopting a two-step heat treatment with a combination of substrate heating at 300C during sputtering and a rapid thermal annealing (RTA) process. The performances of cells deposited at room temperature and at 600C with and without the RTA process are also compared. The LiCoO 2 cathode thin film deposited at 300C with RTA shows a high specific discharge capacity of 65 Ahcm2+-m at a 1C rate and excellent reversibility of the dQdV curve in a half cell using liquid electrolyte. In a LiLiponLiCoO2 structure, a specific discharge capacity of 63.5 Ahcm2+-m is demonstrated, corresponding to 92 of its theoretical value. During charge and discharge the first specific discharge capacity of 60 Ahcm2+-m is observed even at a 5 C rate, demonstrating superior cycling performance over 500 cycles with no capacity degradation. © 2011 The Electrochemical Society.


Lee B.G.,Inha University | Nam S.-C.,GS Nanotech Co. | Choi J.,Inha University
Current Applied Physics | Year: 2012

We investigate the possibility of using a TiO 2 anode as an alternative to the Li electrode in Li-air and Li-ion rechargeable batteries. TiO 2 nanotube layer is fabricated by the anodization method and optional thermal treatment is conducted. The electrochemical charge/discharge profile of the TiO 2/liquid electrolyte/LiCoO 2 structured cell is measured under the flowing of O 2, N 2 and Ar, respectively. The elevation of the upper cut-off voltage from 3 to 4.5 V leads to an increase in the specific capacity by a factor of more than three. We suppose this to be a novel mechanism in which the TiO 2/LiCoO 2 system under the oxygen atmosphere works in Li-air battery mode up to 3 V and then works in Li-ion battery mode from 3 V to 4.5 V. This idea is confirmed by ICP-OES analysis. © 2012 Elsevier B.V. All rights reserved.


Yoon Y.S.,Yonsei University | Jee S.H.,Yonsei University | Lee S.H.,Yonsei University | Nam S.C.,GS Nanotech Co.
Surface and Coatings Technology | Year: 2011

Nano-sized silicon particles were uniformly coated onto a natural graphite surface by a 1 ton/month-based semi-mass production ball milling method in order to prepare Si-based anodes for Li ion batteries. The structure, surface morphology and Si coating properties of the as-synthesized powders were analyzed by XRD, Raman, SEM, TEM and EDS mapping tools. The initial gravimetric discharge capacity of the Si-coated graphite measured using a half cell was 761 mAh/g at a rate of 0.2. C. Additionally, the discharge capacity retention of a full cell system was 71.4% at a 1 C rate even after 300 cycles as well as 96.6% of initial coulombic efficiency. The cycled composite powders were further analyzed by SEM and EDS mapping techniques. This method is proposed for commercial extension to the manufacture of lithium secondary batteries. © 2011 Elsevier B.V.


Lee S.H.,Yonsei University | Jee S.H.,Yonsei University | Lee K.S.,Yonsei University | Nam S.C.,GS NanoTech Co. | Yoon Y.S.,Yonsei University
Electrochimica Acta | Year: 2013

SnPxOy thin films were deposited on stainless steel substrates by electron-beam evaporation for use as anodes in thin-film lithium ion batteries. The thin films were heat-treated at various temperatures for 4 h, and their composition, microstructure, and electrochemical properties were characterized by Rutherford backscattering spectroscopy (RBS), X-ray diffraction (XRD), cyclic voltammetry (CV), and AC impedance spectroscopy. The specific discharge capacity of the as-deposited SnPxOy thin film anode decreased rapidly to 12 μAh cm-2-μm within 10 cycles. However, after heat treatment for 4 h at 500 °C, it maintained a high specific discharge capacity of 136 μAh cm-2-μm and excellent cyclability even after 300 cycles, in contrast to pure SnOx thin film. © 2012 Elsevier Ltd.


Provided is a thin film battery, including: a base substrate; a cathode current collector pattern and an anode current collector pattern being formed on the base substrate to be electrically separated from each other; a cathode pattern being formed on the cathode current collector pattern; an electrolyte pattern being formed on the cathode pattern; and an anode pattern being formed on the electrolyte pattern. At least one pattern of the cathode current collector pattern and the anode current collector pattern may include a non-noble metal based alloy.


The present invention relates to a method for packaging a thin film battery. The method for packaging the thin film battery comprises: a first step of measuring a stacking depth of a package housing stacking space; a second step of correcting a stacking position of each unit battery in order to equalize the average depth formed by stacking each unit battery and the stacking depth of the package housing stacking space, and then sequentially stacking the unit batteries at the corrected stacking positions thereof in the stacking space; and a third step of thermosetting the unit batteries that have finished being stacked. The present invention also relates to an apparatus for a thin film battery package.


Patent
GSNanotech Co. | Date: 2013-10-16

The present invention relates to a thin film battery package. The thin film battery package includes: a case having an open top side and defining a predetermined space therein, wherein the case has one side at which first and second electrodes formed of a metal material are exposed and electrically connected to the outside; a battery block on which a plurality of unit batteries are stacked so that the plurality of unit batteries is electrically connected between a first terminal and a second terminal, wherein the battery block is seated within the case so that the first and second terminals of the unit battery disposed at one end thereof are electrically connected to the first and second electrodes; and a cover sealed and coupled to the top surface of the case. According to the present invention, each of the unit batteries constituting the thin film battery package may be protected against the external environment, principally to prevent charging/discharging efficiency from being significantly reduced under a high temperature atmosphere. Also, since the case is manufactured using a sintering process, the electrodes may be disposed at various positions of the case and have various shapes. Thus, the thin film battery package may be used as a power source for various electrical devices.

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