• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.75-80
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• 2002

Cycle life tests have been carried out to evaluate the influence of safety valve pressure on valve regulated lead/acid batteries under deep cycling applications. Batteries were cycled at 5 hour rates at 100% DOD, and safety valve pressure was set to 1.08 and 2.00 bar, respectively. The batteries lost 248.3 g and 235.3 g of water for each case after about 1,200 cycles, but the cyclic performances of the batteries were comparable. Most of the gas of the battery during discharging was hydrogen, and the oxygen concentration increased to 18% after 3 hours of charging. The micro structure of the positive active materials was completely changed and the corrosion layer of the positive grid was less than $50{\mu}m$, regardless of the pressure of the safety valve after cycle life tests. The cause of discharge capacity decrease was found to be water loss and the shedding of the positive active materials. The pressure of safety valve does not give little effect to the cyclic performances and the failure modes of the gelled electrolyte valve-regulated lead acid batteries.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.998-1002
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• 2008

The gel electrolytes were prepared with sulfuric acid and phosphoric acid, where hydrophilic fumed silica was used as a gelling agent. The influences of gel electrolyte on performance of the valve regulated lead acid (VRLA) batteries were investigated employing capacity tests, electrochemical impedance spectroscopy and scanning electron microscopy. The initial capacities of the sulfuric gel VRLA batteries were higher than that of phosphoric gel VRLA batteries. The sulfuric gel VRLA battery using 1.210 specific gravity of sulfuric acid with hydrophilic fumed silica exhibited the highest capacity of 0.828Ah. In the impedance measurements, the ohmic and charge transfer resistances for the phosphoric gel VRLA batteries were higher thanthat of sulfuric gel batteries. The morphology of electrodes of phosphoric gel VRLA batteries were more deteriorated in the SEM image.

• 전기학회논문지P
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• 제58권2호
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• pp.214-220
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• 2009

Battery is one of the emergency power and its reliability is a very important to keep up the minimum of building capabilities in case of interruption of electric power. This paper, a comparison was made between three different types of instrument on 30 valve regulated lead acid(VRLA) TYPE 12[V]/100[AH] batteries, and then their indicated measured values(impedance/conductance) were compared with the measured capacity of the battery. As a result, Measured value of instrument is strongly related to battery's capacity in the same group battery and Impedance/Conductance guide line for diagnosis of lead-acid battery's state of health(SOH) is a different from each battery guoup.

• 한국응용과학기술학회지
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• 제21권2호
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• pp.164-173
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• 2004

The capacity and long life of gel electrolyte batteries is connected with gas recombination producting $PbO_2$ and Pb electrode. We prepared with sulfuric acid gel electrolyte to know gel characteristics per density to assemble valve regulated lead-acid (VRLA) batteries. We studied on actions of sulphuric acid gel electrolyte by measuring electrolyte dispersion using Brewster-angle microscope (BAM), charge-discharge cycle, and electrode structure using scanning election microscope (SEM). Sulphuric acid density 1.210 showed excellent gel dispersion in sol condition, electrode condition after fifty cycles in this study.

• Korean Chemical Engineering Research
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• 제56권6호
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• pp.779-783
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• 2018

본 연구에서는 차량용 12 V 납축전지로 주로 사용되는 VRLA (Valve regulated lead acid) 배터리의 충/방전 특성과 노화에 따른 이의 변화를 수학적으로 모델링하였다. 기존에 리튬 이온 배터리의 거동 예측에 주로 이용되어 왔던 수학적 모델링 기법을 상용 70 Ah VRLA 배터리에 적용하였다. 정전류 충/방전에 따른 전압의 변화를 모델링 결과와 비교하였다. 비교 결과로부터 사용된 수학적 모델이 납축전지에도 높은 정확도로 적용될 수 있음을 알 수 있었다. 또한 이를 이용하여 납축전지의 노화를 예측할 수 있음을 확인하였다.

• 전기학회논문지
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• 제59권2호
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• pp.248-254
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• 2010

This paper deals with implementation of the laboratory-scale microgrid using energy storage system. Also, this paper develops a simulation model of the microgrid with same parameters on the laboratory-scale microgrid using PSCAD/EMTDC. The experimental results show good agreement with the simulation results. This shows the validity of the simulation model. A valve regulated lead acid (VRLA) battery is used to store energy. Energy storage system with fast response is able to maintain power quality of sensitive load within the microgrid.

• 한국응용과학기술학회지
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• 제25권4호
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• pp.518-524
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• 2008

In this study, positive plates of lead acid battery of Pb-Ca alloy and Pb-Ca-Sn alloy were fabricated and the mechanical characteristics of positive plates were measured. This study observed how the changes of content of Ca & Sn affect interface corrosion which is located in between grid & active materials and lead acid batteries as well. The mechanical characteristics of grid alloy is better when Ca is 0.05 wt.% then 0.1 wt.%. This study said that the corrosion rate between the active material based on the charge/discharge cycle of lead acid battery and grid interface is much faster than a grid which contains Sn. And furthermore, according to the study the rate 30 of Sn/Ca which is added to grid shows the best performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1382-1384
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• 2002

The flooded type battery is used for solar lighting system. Because the characteristic of flooded type battery is the short life time, the maintenance cost is high. So the using flooded type battery in this system is inappropriate. The valve regulated lead acid batter.(VRLA) is the maintenance free and cycle service purpose. This paper presents the development of control system and monitoring system to applied VRLA battery for maintenance free and long life time in system.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.296-308
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• 2003

The capacity and long life of gel electrolyte batteries is connected with gas recombination producting $PbO_2$ and Pb electrode. We were prepared with phosphoric acid gel electrolyte to know gel characteristics per density to assemble VRLA batteries. We studied by measuring electrolyte dispersion using Brewster-angle microscope(BAM), charge-discharge cycle and electrode structure using scanning election microscope(SEM) per electrolyte density. As a results, phosphoric acid density 1.210 was excellent gel dispersion in sol condition, electrode condition after fifty cycles in this study.

• 전기화학회지
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• 제11권1호
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• pp.33-36
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• 2008

본 연구에서는 겔식 VRLA (valve regulated lead acid번지의 충전상태(SoC) 판단을 위해 임피던스 기법을 이용하여 조사하였다. 임피던스는 VRLA전지 (2V/1.2Ah)의 다양한 충전상태에서 진폭 10mV로 100kHz에서${\sim}$10mHz까지 측정하였다. 측정된 임피던스 데이터로부터 등가회로를 유도하고, CNLS (Complex Non-linear Least Squares) 법을 사용하여 분석하였다. 양극 쪽의 전하전이 저항과 전기이중층 커패시턴스가 음극보다 높았다. 겔 저항은 충전상태가 감소함에 따라 증가하며 이는 VRLA 전지의 충전상태를 판단하는데 중요한 파라미터임을 확인하였다.