• 제목/요약/키워드: active electrode

검색결과 569건 처리시간 0.025초

Ketjenblack 전도제 혼합량에 따른 EDLC용 탄소나노섬유 전극의 특성 (Characterization of Carbon Nanofiber Electrode with different Ketjenblack Conducting Material Mixing Amount Using EDLC)

  • 최원경
    • 한국수소및신에너지학회논문집
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    • 제19권2호
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    • pp.163-170
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    • 2008
  • Carbon nanofibers with nano-sized structures were evaluated as a active material using supercacitor electrode which could store electrochemical energy reversibly. A feasibility of EDLC electrode was estimated with specific surface area measurement by BET method and mesopore structure of carbon nanofiber surface could be explained electrochemical absorption-desorption in aqueous electrolyte. A capacitance of carbon nanofiber electrode was increased gradually, depending on the ratio of Ketjenblack as a conducting material. Ketjen Black $20{\sim}25\;wt.%$ ratio in electrode was observed a suitable amount of conducting material by cyclic voltametry results.

소결식 니켈극 제조기술 개발 (Development of Preparation Technique of Sintered Ni Electrode)

  • 김찬중;김대룡
    • 한국수소및신에너지학회논문집
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    • 제10권3호
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    • pp.159-170
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    • 1999
  • Recently Ni/MH secondary battery have been studied very extensively because of containing no pollutants as well as superior performance. However comparing to widely studying high capacity of hydrogen storage alloys electrode, the capacity of Ni electrode is inferior. Using for high capacity Ni/MH battery as a anodic materials, the study about high capacity Ni electrode is necessary. To making high capacity Ni electrode, active materials were impregnated in various polarization impregnation conditions. Plaque, milling for 6hr and sintered at $800^{\circ}C$, indicated porosity over 80%, and porosity were increased with proper condition electrochemical etching treatment. Proper impregnation condition was 40~80mA/cm, polarizing time was 5~10min.

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수직형구조 GaN계 발광다이오드에서 전극구조 모양에 따른 3차원 전류분포 해석 (Analysis of 3-Dimensional Current Flow by n-electrode Pattern Shape in GaN-based Vertical LED)

  • 윤주선;심종인
    • 한국광학회:학술대회논문집
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    • 한국광학회 2008년도 동계학술발표회 논문집
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    • pp.231-232
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    • 2008
  • The effect of n-electrode patterns on the current distribution in active region is investigated in GaN-based blue vertical light emitting diodes (VLEDs). A 3-dimension circuit model is adopted to analyze the current flow patterns in VLEDs. We had fabricated VLEDs having different n-electrode patterns, measured their current-voltage characteristics, and compared to the numerical simulation. It turns out that the current spreading in VLEDs is strongly dependent on the n-electrode pattern. Some design guidelines for n-electrode patterns to produce uniform current injection are presented.

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중첩형 다단전극에 의한 효율적인 전해 이온수 발생 특성 (Effective Electrolytic Water Generation Characteristics by Overlapped Multi-layer Electrode)

  • 신동화;황덕현;정재승;김형표;김진규
    • 조명전기설비학회논문지
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    • 제30권3호
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    • pp.59-64
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    • 2016
  • Applications of electrolytic ion water generated by the oxidation-reduction have gradually been expanded due to their strong sterilizing power and a surface active force. We demonstrate the effect of the multi-layer type electrode for effective ion water generation. The multi-layer type electrode has ability to generate stronger acid and alkali water by increase of the electrode reactive area. Also power consumption efficiency enhances because the electrodes disposed in middle position of the reactive cell raise the usage rate by overlapped effect as an electrolysis electrode.

다황화암모늄에 의해 제조된 황화니켈을 이용한 리튬전지의 전기 화학적 특성 평가 (Electrochemical Properties of Lithium Batteries with Nickel Sulfide by Ammonium Polysulfide)

  • 유호석
    • 한국수소및신에너지학회논문집
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    • 제32권6호
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    • pp.612-617
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    • 2021
  • In the case of a metal sulfide electrode, it is used as an anode or cathode active material in a lithium battery. The reason is that the voltage exists between 0.8 and 2.0 V via lithium electrode and the discharge and charge capacity is high. In order to manufacture nickel sulfide for electrode, which are widely used, nano-nickel powder was sulfided using ammonium polysulfide, and single-phase NiS electrodes were manufactured through heat treatment. The prepared NiS electrode had a high initial capacity of 500 mAh/g or more, and was stabilized after 20 cycles to maintain a capacity of 400 mAh/g or more until 100 cycles.

INVESTIGATION OF "STEPPED" DISCHARGE CURVES IN SINTERED TYPE NICKEL-CADMIUM CELL

  • SASAKI, Y.;YAMASHITA, T.
    • 한국표면공학회지
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    • 제32권3호
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    • pp.360-362
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    • 1999
  • Formation of the nickel-cadmium alloy in the negative electrode of nickel-cadmium cell subjected to continuous charging at elevated temperatures ($40~45^{\circ}C$) is shown to be one of the causes of the 'stepped' discharge curves. The alloy has been characterized by electrode potential measurement and X-ray diffraction method. The potential lowering during discharge is related to discharge of the alloy. X -ray diffraction suggests that the nickel-cadmium alloy can be formed during charge in negative electrode by interaction of the two metals. Addition of Ni $(OH)_2$ into $Cd{\;}(OH)_2$ active material is found to form the alloy more readily than sintered negative electrode alone.ode alone.

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Enhancement of Quick-Charge Performance by Fluoroethylene Carbonate additive from the Mitigation of Electrode Fatigue During Normal C-rate Cycling

  • Tae Hyeon Kim;Sang Hyeong Kim;Sung Su Park;Min Su Kang;Sung Soo Kim;Hyun-seung Kim;Goojin Jeong
    • Journal of Electrochemical Science and Technology
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    • 제14권4호
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    • pp.369-376
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    • 2023
  • The quick-charging performance of SiO electrodes is evaluated with a focus on solid electrolyte interphase (SEI)-reinforcing effects. The study reveals that the incorporation of fluoroethylene carbonate (FEC) into the SiO electrode significantly reduced the electrode fatigue, which is from the the viscoelastic properties of the FEC-derived SEI film. The impact of FEC is attributed to its ability to minimize the mechanical failure of the electrode caused by additional electrolyte decomposition. This beneficial outcome arises from volumetric stain-tolerant characteristics of the FEC-derived SEI film, which limited exposure of the bare SiO surface during 0.5 C-rate cycling. Notably, FEC greatly improves Li deposition during quick-charge cycles following aging at 0.5 C-rate cycling due to its ability to maintain a strong electrical connection between active materials and the current collector, even after extended cycling. Given these findings, we assert that mitigating SEI layer deterioration, which compromises the electrode structure, is vital. Hence, enhancing the interfacial attributes of the SiO electrode becomes crucial for maintaining kinetic efficiency of battery system.

격자 볼츠만법을 이용한 리튬이온전지의 활물질 혼합비에 대한 함침성의 영향 (Effect of Mixing Ratio of Active Material on the Wettability in Lithium-Ion Battery Using Lattice Boltzmann Method)

  • 전동협
    • 대한기계학회논문집B
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    • 제40권1호
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    • pp.47-53
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    • 2016
  • 격자 볼츠만법을 이용하여 리튬이온전지의 전극 내 발생하는 전해액 함침 현상에 관하여 연구하였다. 최근 리튬이온전지는 용량 증가 및 에너지밀도 향상을 위하여 전극 설계시 활물질에 미세입자를 혼합하고 있어, 이로 인하여 전해액 함침성에 영향을 미치게 될 수 있다. 본 연구에서는 활물질 혼합율에 따른 전해액 분포와 포화도 변화를 알아보았다. 활물질 혼합비의 변화는 전극 내 전해액 함침 메커니즘에 영향을 주어, 전해액 함침속도와 함침도가 변화함을 확인하였다.

Active Vibration Control of Composite Shell Structure using Modal Sensor/Actuator System

  • Kim, Seung-Jo;Hwang, Joon-Seok;Mok, Ji-Won
    • International Journal of Aeronautical and Space Sciences
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    • 제7권1호
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    • pp.106-117
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    • 2006
  • The active vibration control of composite shell structure has been performed with the optimized sensor/actuator system. For the design of sensor/actuator system, a method based on finite element technique is developed. The nine-node Mindlin shell element has been used for modeling the integrated system of laminated composite shell with PVDF sensor/actuator. The distributed selective modal sensor/actuator system is established to prevent the effect of spillover. Electrode patterns and lamination angles of sensor/actuator are optimized using genetic algorithm. Continuous electrode patterns are discretized according to finite element mesh, and orientation angle is encoded into discrete values using binary string. Sensor is designed to minimize the observation spillover, and actuator is designed to minimize the system energy of the control modes under a given initial condition. Modal sensor/actuator for the first and the second mode vibration control of singly curved cantilevered composite shell structure are designed with the method developed on the finite element method and optimization. For verification, the experimental test of the active vibration control is performed for the composite shell structure. Discrete LQG method is used as a control law.

수중 방전과 공간전하제어에 의한 효과적인 산화성물질 발생특성 (Effective Oxidant Generation and Ion Precipitation Characteristics of Electrolyzing Cell by Discharge and Space Charge Control)

  • 김진규;이대희;문재덕
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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    • pp.9-12
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    • 2000
  • A new type electrolyzing cell with slits on parallel plate electrodes and wire-to-cylinder type electrode system has been proposed instead of the conventional parallel plate type. An investigation was carried out on the effect of the number and size of slits on ion precipitation and oxidant generation characteristics, evidenced by eliminated space charge limiting action and by elevated electric fields in active interelectrode spacing. And it is also studied on the effect of the diameter of wire electrode to ion precipitation and oxidant generation characteristics. With electrode with 48 slits, very oxidants generation water of 3.1 [ppmm] and 19.0 [ppmm] in positive electrode side were obtained with tap water and 0.1 [wt%] NaCl dissolved tap waterfed. In addition, with wire-to-cylinder type electrode system, it is found that oxidant contained water of 0.48 [ppmm] and 5.46 [ppmm] in positive electrode side were obtained with tap water and 0.1 [wt%] NaCl dissolved tap water fed for the case of discharge electrode diameter of 0.5 [$mm{\phi}$]. Consequently, very high ion precipitation and dense oxidant generation characteristics can be realized by having slits on the electrodes of conventional cell as these slits increase the electric fields and decrease the space charge limiting actions in interelectrode spacing.

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