• Title/Summary/Keyword: Discharge Properties

검색결과 1,330건 처리시간 0.026초

Synthesis and Characterization of Silver Vanadium Oxide as a Cathode for Lithium Ion Batteries

  • Nguyen, Van Hiep;Gu, Hal-Bon
    • Transactions on Electrical and Electronic Materials
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    • 제17권3호
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    • pp.139-142
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    • 2016
  • β-AgVO3 nanorods have been successfully synthesized using a soft chemistry route followed by heat treatment. They were characterized by X-ray diffraction and field emission scanning electron microscopy, and their electrochemical properties were investigated using cyclic voltammetry, impedance spectra, and charge-discharge tests. The results showed that the smooth-surfaced nanorods are very uniform and well dispersed, with diameters of ~100-200 nm and lengths of the order of several macrometers. The nanorods deliver a maximum specific discharge capacity of 275 mAh g-1 at 30 mA g-1. They also demonstrated good rate capability with a discharge capacity at the 100th cycle of 51 mAh g-1.

Fabrication and Characterization of Electrical Discharge Machinable $Si_3N_4$-TiN Composites

  • Park, Heon-Jin;Kim, Young-Wook;Lee, June-Gunn;Lee, Soo W.;Chung, Soon-Kil
    • The Korean Journal of Ceramics
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    • 제1권2호
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    • pp.101-105
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    • 1995
  • Electrical discharge machinable $Si_3N_4$ was fabricated with the addtion of 20-60 vol% TiN by gas pressure sintering. Their sinterability, microstructure, mechanical and electrical properties were characterized as a function of the TiN content. The addition of TiN up to 20 vol% increased the flexural strength and fracture toughness as compared with those of the monolithic Si3N4. For the TiN content higher than 40 vol%, the electrical resistivity was lower than $1062\Omega$.cm. The $Si_3N_4$ with the addition of 40 vol% of TiN appears to have the optimum considerable sinterability, mechanical and electrical properties, and machinability. A microstructural analysis showed that the enhanced toughening was due to the crack deflection.

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Properties of Electrical Discharge Machinable $SiC-TiB_2$ Composites

  • Kim, Young-Wook;Park, Heon-Jin;Lee, June-Gunn;Lee, Soo W.;Chung, Soon-Kil
    • The Korean Journal of Ceramics
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    • 제1권3호
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    • pp.125-130
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    • 1995
  • Electrical discharge machinable $SiC-TiB_2$ composites were fabricated by hot-pressing. Their mechanical and electrical properties were determined as a function of $TiB_2$ content. The addition of $TiB_2$ to SiC matrix increased the strength and toughness and decreased electrical resistivity. The flexural strength and fracture toughness of SiC-40 vol% $TiB_2$ composited were approximately 50% higher than those of monolithic SiC ceramics. Microstructural analysis showed that the toughening was mainly due to the crack deflection, with some possible contribution from crack branching or microcracking.

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군집 최적화를 이용한 열화 진단 알고리즘 개발 (The Algorithm Development of Aging Diagnosis Using Swarm Optimization)

  • 김기준
    • 한국전기전자재료학회논문지
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    • 제26권2호
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    • pp.151-157
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    • 2013
  • In this paper, properties of pattern using LBG (Linde-Buzo-Gray) Algorithm was explored including the exactness of K-means algorithm and process time of EM (Expectation Maximization) algorithm in order to develop analysis algorithm of partial discharge pattern in a cable using acoustic data analysis system. Partial discharge was measured by generating inner fault due to lamination of XLPE which is used for cable insulation material. Discharge pattern was analysed by changing the number of swarm article to 2, 4, and 6 in order to interpret swarm structure and properties.

방전처리에 따른 Poly(ethylene terephthalate) 필름의 표면특성에 관한 연구 (A Study on the Surface Properties of Poly(ethylene terephthalate) films by Discharge Treatment)

  • 임경범;이백수;이상희;황명환;박구범;박종관;김영일;임헌찬;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.1587-1589
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    • 2000
  • In this paper the weight loss, surface potential decay, surface resistivity and dielectric constant are measured to investigate the surface properties, insulation characteristic changes of PET film according to the discharge treatment. As a result of the test, up to the 10[min] the surface potential decay and surface resistivity have increased. Also, from the result of dielectric constant has decreased. On the other hand, the insulation characteristic of PET film have decreased after 10[min] in the discharge treatment.

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침 전극에 의한 초고압 케이블 절연재료의 부분방전 특성 (Partial Discharge Characteristics of Ultra-High Voltage Cable Insulators by Needle Electrode)

  • 김균식;최범규;변두균;조경순;김귀열;이충호;홍진웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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    • pp.477-480
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    • 2004
  • In other to estimate an electrical properties of the cross linked polyethylene cable, the partial discharge properties due to charge of electrode shape(needle and bar) and void size were investigated at room temperature. Fast trip and breakdown time were appeared by the closed of needle electrode. The trip and breakdown voltage depend on insulator thickness. As the result, confirmed larger effect of void size than effect of insulator thickness. The effect of voids size than influence of insulation thickness was dominated by internal an electrode of inner insulators.

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보강제 변화에 따른 실리콘 고무의 트래킹 열화 특성에 관한 연구 (A Study on Tracking Degradation Properties of Silicone Rubber due to Reinforcing Agent)

  • 이성일
    • 한국전기전자재료학회논문지
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    • 제27권12호
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    • pp.841-846
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    • 2014
  • It found that the maximum temperature of the arc discharge occurred on the Silicone rubber sample significantly decreased with increasing the reinforcing agent. It was confirmed that the current value decreased with increasing the aluminium trihydrate($Al(OH)_3$) and the current value increased with reducing the primary resistance over time. Regarding these results, may be it is because the degradation due to the electro-conductive carbonization was improved and the properties of dielectric breakdown was reduced by the flame retardant reinforcing agent. It found that the electro-conductive carbonized road has not happened by increasing the flame retardant reinforcing agent. Regarding to the arc discharge, this study show that the arc arising near the lower electrode of sample has disappeared.

PPP-based Carbon/Li cell의 임피던스 특성 (The Impedance Properties of Poly(p-phenylene)-based Carbon/Li cell)

  • 류현옥;홍성문;김주승;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.283-285
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    • 1997
  • We have obtained disordered carbon by pyrolyzing PPP in a nitrogen atmosphere for 8 hour at 700$^{\circ}C$. AC impedance property was measured with the PPP-based carbon/EC-DEC/Li cell. The impedance spectra of the cell were measured during the 1st discharge proceed. As the result of measurement the cell resistance decreased in intial discharge, but increase in final discharge.

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Polyaniline 필름의 산화환원 특성 및 리튬 2차 전지 응용 (Redox Properties of Polyaniline Films and Its Application to Lithium Secondary Batteries)

  • 김현철;박영철;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.144-148
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    • 1997
  • We synthesized polyaniline films electrochemically under constant current conditions, which exhibited electric conductivity as high as 100 S/cm. By charge and discharge cycling of polyaniline films, we obtained specific discharge capacity as high as 195 mAH/g using HSO$_4$- doped polyaniline. For the polyaniline synthesized using H$_2$SO$_4$ and HClO$_4$ composite electrolyte. we also obtained specific discharge capacity as high as 134 mAHg which rivals inorganic electro- active materials.

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Preparation and Electrochemical Properties of Carbon Cryogel for Supercapacitor

  • Song, Min-Seob;Nahm, Sahn;Oh, Young-Jei
    • 한국세라믹학회지
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    • 제45권11호
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    • pp.662-666
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    • 2008
  • Electrochemical properties of carbon cryogel electrode for the application of composite electrode materials mixed with metal oxide in supercapacitor have been studied. Carbon cryogels were synthesized by sol-gel polycondensation of resorcinol with form aldehyde, followed by a freeze drying, and then pyrolysis in an inert atmosphere. Physical properties of carbon cryogel were characterized by BET, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that carbon cryogel is amorphous material. The electrochemical properties of carbon cryogel were measured by cyclic voltammetry as a function of concentration of liquid electrolyte, galvanostatic charge-discharge with different scan rates and electrochemical impedance measurements. The result of cyclic voltammetry indicated that the specific capacitance value of a carbon cryogel electrode was approximately 150.2 F/g (at 5 mV/s in 6M KOH electrolyte).