• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.283-287
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• 2007

KIER has been developing the anode-supported flat tubular solid oxide fuel cell unit bundle for the intermediate temperature($700{\sim}800^{\circ}C$) operation. Anode-supported flat tubular cells have Ni/YSZ cermet anode support, 8 moi.% $Y_2O_3$ stabilized $ZrO_2(YSZ)$ thin electrolyte, and cathode multi-layer composed of Sr-doped $LaSrMnO_3(LSM)$, LSM-YSZ composite, and $LaSrCoFeO_3(LSCF)$. The prepared anode-supported flat tubular cell was joined with ferritic stainless steel cap by induction brazing process. Current collection for the cathode was achieved by winding Ag wire and $La_{0.6}Sr_{0.4}CoO_3(LSCo)$ paste, while current collection for the anode was achieved by using Ni wire and felt. For making stack, the prepared anode-supported flat tubular cells with effective electrode area of $90\;cm^2$ connected in series with 12 unit bundles, in which unit bundle consists of two cells connected in parallel. The performance of unit bundle in 3% humidified $H_2$ and air at $800^{\circ}C$ shows maximum power density of $0.39\;W/cm^2$ (@ 0.7V). Through these experiments, we obtained basic technology of the anode-supported flat tubular cell and established the proprietary concept of the anode-supported flat tubular cell unit bundle.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.520-524
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• 2011

The properties of manufactured SOFC unit cell using decalcomania method were investigated. The decalcomania method that used in ceramics, dish, vessel and etc. was the very simple process. The SOFC unit cell manufacturer using decalcomania method is very simple process. Especially, the decalcomania method was the most suitable manufacturing method for the segmented type SOFC. The cathode, prevent diffusion layer (PDL), anode functional layer (AFL) and electrolyte were manufactured using decalcomania method on porous anode support. The sintered electrolyte at 1450$^{\circ}C$ for 2 h using decalcomania method was very dense, and the thickness was about 10 ${\mu}m$. The cathode, the PDL and the AFL were manufactured using decalcomania method and was sintered at 1250$^{\circ}C$ for 2 h, and the sintered electrodes were the porous. As a result, with humidified hydrogen used as fuel, the cell with an 15 ${\mu}m$-thick AFL exhibited maximum power densities of 0.246, 0.364, 0.504W/$cm^2$ at 700, 750, 800$^{\circ}C$, respectively.

• Ceramist
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• v.21 no.4
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• pp.388-405
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• 2018

In this paper, we review about current development of electrode materials for Li-ion batteries and catalysts for fuel cells. We scrutinized various electrode materials for cathode and anode in Li-ion batteries, which include the materials currently being used in the industry and candidates with high energy density. While layered, spinel, olivine, and rock-salt type inorganic electrode materials were introduced as the cathode materials, the Li metal, graphite, Li-alloying metal, and oxide compound have been discussed for the application to the anode materials. In the development of fuel cell catalysts, the catalyst structures classified according to the catalyst composition and surface structure, such as Pt-based metal nanoparticles, non-Pt catalysts, and carbon-based materials, were discussed in detail. Moreover, various support materials used to maximize the active surface area of fuel cell catalysts were explained. New electrode materials and catalysts with both high electrochemical performance and stability can be developed based on the thorough understanding of earlier studied electrode materials and catalysts.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.129-132
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• 2007

Advanced structure of metal-supported solid oxide fuel cells was devised to overcome sealing problem and mechanical instability in ceramic-supported solid oxide fuel cells. STS430 whose dimensions were 26mm diameter, 1mm thickness and 0.4mm channel width was used as metal support. Thin ceramic layer composed of anode(Ni/YSZ) and electrolyte(YSZ) was joined with STS430 metal support by using a cermet adhesive. $La_{0.8}Sr_{0.2}Co_{0.4}Mn_{0.6}O_{3}$ perovskite oxide was used as cathode material. It was noted that oxygen reduction reaction of cathode governed the overall cell performance from oxygen partial pressure dependance.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.769-774
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• 2011

Porous carbon nanofibers(CNF) were synthesized via NaOH activation at 700~$900^{\circ}C$, and the porous CNF-supported PtRu catalysts were evaluated for the anode in direct methanol fuel cells. The change of surface characteristics by NaOH activation was examined by analyses of the specific surface area and pore size distribution. The morphological and structural modification was investigated under scanning electron microscopy. The activity of catalysts supported on porous CNFs was examined by cyclic voltammograms and single cell tests. The pore formation on CNF by the NaOH activation was discussed, concerning the catalyst activity, when they were applied as catalyst supports.

• Carbon letters
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• v.4 no.3
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• pp.121-125
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• 2003

The Pt-Ru/Carbon as an anode catalyst supported on the commercial activated carbon (AC) having high surface area and micropore was characterized for application of Direct Methanol Fuel Cell (DMFC). The Pt-Ru/AC anode catalyst used in this experiment showed the performance of $600\;mA/cm^2$ current density at 0.3 V. The borohydride reduction process using $NaBH_4$, denoted as a process A, showed much higher current and power densities than process B prepared by changing the reduction and washing process of process A. The particle sizes are strongly affected by the reduction process than the specific surface area of raw active carbon and the sizes are almost constant when the specific surface area of carbon are over than the $1200\;m^2/g$. Smaller particle size of catalyst and more narrow intercrystalite distance increased the performance of DMFC.

• Carbon letters
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• v.20
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• pp.47-52
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• 2016

Physical and electrochemical qualities were analyzed after KOH activation of a direct methanol fuel cell using needle coke as anode supporter. The results of research on support loaded with platinum-ruthenium suggest that an activated KOH needle coke container has the lowest onset potential and the highest degree of catalyst activity among all commercial catalysts. Through an analysis of the CO stripping voltammetry, we found that KOH activated catalysis showed a 21% higher electrochemical active surface area (ECSA), with a value of 31.37 m² /g, than the ECSA of deactivated catalyst (25.82 m² /g). The latter figure was 15% higher than the value of one specific commercial catalyst (TEC86E86).

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.6
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• pp.467-471
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• 2013

In present work, optimized the manufacturing process of anode-supported tubular SOFCs cell and stack were studied. For this purpose, we first developed a high performance tubular SOFC cell, and then made electrical connection in series to get high voltage. The gas sealing was established by attaching single cells to alumina jig with ceramic bond. Through these process, we can obtain such high OVP as around 15V, which means that the electrical connection and gas sealing were optimized. Finally we developed a new tubular SOFC stack which shows a maximum power of 65W @ $800^{\circ}C$.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.77-82
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• 2011

In this study, a metal-supported SOFC was fabricated using a relatively cheap and simple process. The adhesion process between ceramic cell and metal support was performed in high temperature over $1400^{\circ}C$ and the deformation of large metal-supported cell happened in this process. Using bi-layered metal support fabricated by diffusion bonding, the deformation of the metal-supported cell can be minimized and the sealing efficiency of anode and cathode was improved. The flatness of the cell was improved by over 20% and the maximum power density of over 0.5 $Wcm^{-2}$ was obtained at the operation condition of $800^{\circ}C$.

• Transactions on Electrical and Electronic Materials
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• v.12 no.1
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• pp.1-6
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• 2011

This paper summarized concept, manufacture and results of the micro-tubular solid oxide fuel cells (SOFCs). The cells were fabricated by co-sintering of extruded micro-tubular anode support and electrolyte coating layer, and then additional cathode coating. The cells showed quick voltage rising within 1 minute, and the electrochemical performances were closely related to the balance of fuel utilization and performance loss. And a thermal-fluid simulation model was also reported in combination with the electrochemical evaluation results on the GDC-based micro-tubular SOFCs.