Hee-Chun Lim

수계 테이프 케스팅 법에 의한 봉상 γ-LiAlO₂ 입자 강화 MCFC 매트릭스 제조 공정의 최적화

Rod-shaped particle reinforced LiAlO₂ matrices for MCFC were fabricated by an aqueous tape-casting technique. The hydrolysis reaction and agglomeration of γ-LiAlO₂ particles in aqueous slurries were inhibited by additions of LiOH·H₂O and glycerin to the aqueous γ-LiAlO₂ slurry. The tape-casting, performed using the aqueous slurry containing protein albumin, was fast and led to an effective drying at casting temperature range of 60~65℃. The strength of the particle reinforced matrix was improved about 4 times compared to that of matrix without reinforcement. Pore size distribution (0.1~0.4 ㎛) and porosity (50~60%) of the reinforced matrices were determined to be appropriate for the MCFC matrix. The aqueous tape casting process is not only environmental-friendly but also efficient for fabricating MCFC matrices compared to non-aqueous tape casting.

Effect of Anode Thickness on the Overpotential in a Molten Carbonate Fuel Cell

This work investigated the effect of anode thickness on the anodic overpotential with 100 cm 2 class MCFC single cells. The hydrogen oxidation rate in the molten carbonate is suf- ficiently high, which may lead to weak relation of overpotential with anode geometrical area. The relation of anode surface area and overpotential was analysed in terms of anode thickness in this work. Steady state polarization, inert gas step addition (ISA), and reactant gas addition (RA) methods were employed to the two cells with 0.77 mm and 0.36 mm thickness of anode. The result represented that the anodic overpotential at the cells were identical. It implied that the anodic overpotential was independent on the electrode thickness within the tested range.

Effect of Anodic Gas Compositions on the Overpotential in a Molten Carbonate Fuel Cell

Anodic overpotential has been investigated with gas composition changes in a class molten carbonate fuel cell. The overpotential was measured with steady state polarization, reactant gas addition (RA), inert gas step addition (ISA), and electrochemical impedance spectroscopy (EIS) methods at different anodic inlet gas compositions, i.e.,

Operation Results of the External Reforming Type 75kW Class MCFC Stack

H_2:CO_2:H_2O

Mathematical modeling of a molten carbonate fuel cell (MCFC) stack

A 75kW class pilot scale MCFC stack composed of 128 unit cells was assembled and operated. 10,000cm2 class MCFC stack components are also developed to fabricate the MCFC stack. The separators with the effective area of 10,000 cm2 were adopted new design concepts such as 3-piece architecture, simple channel structure, and flat mask plate to improve the gas flow behavior and wet seal performance. The electrolyte impregnated anode and cathode with the effective area of 10,000 cm2 were fabricated by the ex-situ process to enhance the reliability of the stack during the heat-treatment. Finally, the gas distribution manifold embedded light-weight stack structure was employed. The stack showed the average open circuit voltage of 1.065V that near meet theoretical one and 78.5kW DC in power output. A 125kW class MCFC stack using the same components will be assembled and started to operate by the end of 2009.