• 전력전자학회논문지
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• 제9권4호
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• pp.319-325
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• 2004

무공해 자동차를 만들기 위해 중요한 요소로서는 주행거리와 알맞은 가격이다. 니켈-수소 배터리와 같은 향상된 배터리의 개발은 부분적으로 문제를 해결할 수 있으며, 또 하나의 효과적인 방법은 배터리 관리 시스템이나. 니켈-수소 배터리와 배터리 ECU는 주행거리, 가속도, 등판능력과 같은 무공해 자동차의 성능에 영향을 미치는 중요한 구성품이다. 예컨대 운행 중 쉽게 발생하는 단락, 과방전, 과충전은 배터리와 관계되는 가장 큰 문제점이기 때문에 전용의 HEV용 배터리 ECU의 개발은 필수적이다. 본 논문에서는 배터리 전류적산 및 전압에 기초한 HEV용 SOC 알고리즘을 제안하고 배터리 ECU를 설계 및 해석하였으며, 시험을 통해 타당성을 검증하였다.

• 공업화학
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• 제8권6호
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• pp.1034-1040
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• 1997

전기자동차의 동력원으로 사용되는 90Ah급 Nickel/Metal hydride 전지 11개로 구성된 module의 온도특성을 상용 software인 NISA II를 사용하여 해석하였다. 전지 module에 대한 element수를 감축하기 위하여 열전도도가 다른 여러 층을 통하여 전달되는 열흐름에 대한 해석을 전기저항 등가식을 사용하여 단순화하였으며, Cartesian coordinate의 축별로 다른 열전도도를 삽입하는 orthotropic model을 사용하였다. 전지 module의 온도를 낮추기 위하여 알루미늄 재질의 cooling fin을 전지와 전지사이에 삽입하여 실험을 수행하였고, 전지 module 최외곽에 위치한 fin에 의한 최고온도의 강하 효과는 미미하다는 결과를 얻었다. 전지 module내 전지별 온도차이를 극소화하기 위하여 cooling fin의 개수와 두께 그리고 측면 fin의 복합적인 영향에 대한 실험을 수행하였으며, 1mm 두께의 알루미늄 fin을 4개 사용하여 module내 전지별 최고온도의 차이를 $3^{\circ}C$ 이내로 줄일 수 있었다.

• 전기화학회지
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• 제10권1호
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• pp.31-35
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• 2007

이 리뷰를 통하여, 휴대폰용 리튬이차전지의 최근 기술동향을 설명하였다. 휴대폰용 이차전지로는 니카드, 니켈-금속수소, 리튬이온 혹은 리튬이온폴리머의 세 가지 형태의 전지가 있으며, 리튬 이차전지가 에너지밀도 측면에서 가장 성능이 우수하다. 즉, 동일한 용량을 갖는 이차전지 가운데 가장 작고 가벼운 것은 리튬이차전지이다. 이러한 리튬이차전지의 시장은 매년 약 15%의 높은 성장을 기록하고 있다. 연구개발은 $LiFePO_4$를 포함하는 새로운 양극, $Li_4Ti_5O_{10}$, Si, 주석 등의 새로운 음극소재, 새로운 전해질과 안정성 확보에 관한 것을 중심으로 진행되고 있다.

• 한국수소및신에너지학회논문집
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• 제3권2호
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• pp.9-15
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• 1992

Electroless copper plating method using an alkaline bath have been employed in copper coating of the (LM)Ni4.5Co0.1MnO.2A10.2 hydrogen storage alloy powders for electrode preparation. The plating were conducted without any pretreatment of alloy powders. For the preparation of the electrodes, about 0.12g of the copper coated alloy powder (copper to alloy ratio 1/3 by weight) was compacted with pressure of 6 tons/cm2 at room temperature. The disk-type compacts had a diameter of 10mm and thickness of about 0.24mm. The electrode characteristics were examined through SEM observations and electrochemical measurements in a half cell. The electrochemical measurement showed that the maximum discharge capacity of the electrodes prepared by using alkaline bath were 245mAh per gram of coated alloy (327mAh per gram of alloy) and appeared a considerable degradation with increasing number of cycles. The decrease of the discharge capacity after 100 cycles was about 30% It can be suggested that, with a slight of improvement, this electroless copper plating method could be applied to the preparation of the rare earth-nickel based alloy electrode.

• 한국수소및신에너지학회논문집
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• 제27권2호
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• pp.163-168
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• 2016

Korea has been developing nuclear fusion fuel storage and delivery system (SDS) technologies including a basic scientific study on hydrogen storage. To develop nuclear fusion technology, it is necessary to store and supply hydrogen isotopes needed for Tokamak operation. SDS is used for storing hydrogen isotopes as a metal hydride form. The rapid hydriding of tritium is very important not only for safety reasons but also for the economic design and operation of the SDS. In this study, we designed and fabricated a medium-scale getter bed of depleted uranium (DU). The hydriding of DU has been measured by varying the initial temperature ($100-300^{\circ}C$) of the DU getter bed to investigate the influence of the cooling temperature. Furthermore, we analyzed the effect of a helium blanket on the hydriding performance with 0 - 12% helium content in hydrogen.

• 한국수소및신에너지학회논문집
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• 제27권1호
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• pp.22-28
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• 2016

It is necessary to store and supply hydrogen isotopes for Tokamak operation. A storage and delivery system (SDS) is used for storing hydrogen isotopes as a metal hydride form. We designed and fabricated a depleted uranium (DU) bed to store hydrogen isotopes. The rapid storage of hydrogen isotopes is very important not only for safety reasons but also for the economic design and operation of the SDS. The delivery rate at the desorption temperatures without the operation of a dry pump was analyzed in comparison with that with the operation of the dry pump. The effect of the initial desorption temperatures on the dehydriding of the DU without the operation of the dry pump was measured. The effect of the initial desorption temperatures on the dehydriding of DU with the operation of the dry pump was also measured and analyzed. The primary pressure on the desorption temperatures without the operation of the dry pump was analyzed in comparison with that with the operation of the dry pump. The temperature gradient of the coil heater and the primary vessel was also analyzed. Our results will be used to develop pilot scale hydrogen isotope processes. It was confirmed that dehydriding of a medium-scale DU bed has enabled without the operation of the dry pump.

• 한국재료학회지
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• 제27권12호
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• pp.672-678
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• 2017

In the production of zirconium cladding tube, a pickling acid solution is used to remove surface contaminants, which generates tons of pickling acid waste. The waste pickling solution is a valuable resource of Hf-free Zr. Many studies have investigated separating the Hf-free Zr source from the waste pickling acid. The results showed that $Ba_2ZrF_8$ precipitates prepared from the waste pickling acid were useful as an electrolyte for the electrorefining of Zr in molten salt. In the present work, electrorefining was performed in a $Ba_2ZrF_8-LiF$ binary electrolyte to recover Zr from a Hf-free CuZr ingot anode prepared by electroreduction. Before electrorefining, two pretreatments are performed. First, electrolyte melting was carried out to determine the eutectic temperature, and second, the electrolyte was treated to eliminate impurities, mainly hydride. After electrorefining, the cathode deposits were analyzed by $O_2$ gas analyzer and SEM-EDX to explore the possibility of recovering nuclear-grade Zr metal. Moreover, the anode was analyzed by SEM-EDX to determine the Zr dissolution depth.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.897-900
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• 2005

This paper presents temperature control of aluminum plate using Peltier module. As one of the thermoelectric effect, Peltier effect is heat pumping phenomena by electric energy. So if current is charged to Peltier module, it absorbs heat from low temperature side and emits heat to high temperature side. In this experiment, Peltier module is used to control the temperature of small aluminum plate with heating and cooling ability of Peltier module with current control and fan On/OFF control. And current control of Peltier module was accomplished by PWM method. As a results of experiments, it takes about 125sec to control temperature of aluminium plate between $30^{\circ}C\;and\;70^{\circ}C$ and about 70sec between $40^{\circ}C\;and\;60^{\circ}C$, in ambient temperature $29^{\circ}C$ while operating cooling fan only while cooling duration. Future aim is to realize more rapid temperature control and develop SMHA(special metal hydride actuator) by using Peltier module as a heating and cooling source.

• 대한금속재료학회지
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• 제50권2호
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• pp.183-190
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• 2012

Hydrogen was generated by the reaction of metal hydride with water. The variation of hydrogen generation with the kind of powders (milled $MgH_2$, and $MgH_2$ milled with various contents of MgO, $MgCl_2$ or $Ni+Nb_2O_5$) was investigated. $MgH_2$ powder with a hydrogen content of 6.05 wt% from Aldrich Company was used. Hydrogen is generated by the reaction of Mg as well as $MgH_2$ with water, resulting in the formation of byproduct $Mg(OH)_2$. For about 5 min of reaction time, milled $95%MgH_2+5%MgO$ has the highest hydrogen generation rate among milled $MgH_2+x%MgO$ (x=0, 5, 10, 15 and 20) samples. Milled $90%MgH_2+10%MgCl_2$ has the highest hydrogen generation rate among all the samples.

• 한국수소및신에너지학회논문집
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• 제7권2호
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• pp.157-164
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• 1996

The AB5-type metal hydride electrodes using $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$(LM : Lanthaniumrich Mischmetal) alloy powders(${\leq}200$mesh) which were coated with 25wt% copper in an acidic bath were prepared with or without addition of 10wt% PTFE as a binder. Prior to electrochemical measurements, the electrodes were sintered at $40^{\circ}C$ for 1 and 2hrs in vacuum with Mm(mischmetal) and sponge type Ti getters. The properties such as maximum capacity, cycle life and mechanical strength of the negative electrode have been investigated. The surface analysis of the electrode was also obtained before and after charge-discharge cycling using scanning electron microscope(SEM). From the observations of electrochemical behavior, it was found that the sintered electrode shows a lower maximum discharge capacity compared with non-sintered electrode but it shows a better cycle life. For the both electrodes with or without addition of PTFE binder, the values of mechanical strength were obtained, and their values increased with increasing sintering time. However, there is little difference of discharge capacity for both electrodes.