MCFC 작동온도인 650˚C에서 음극의 creep과 소결에 의한 구조적 변형을 막기 위해 기계적 합금법에 의한 Ni-WC분말을 합금화하여 변형에 대한 저항성을 증대시키고자 하였다. 80시간동안 어트리션 밀링을 실시한 분말은 XRD 분석결과 결정규칙이 파괴된 비정질 상을 보였다. 제조된 분말은 적당한 점도의 슬러리로 제조후 테이프 캐스팅법에 의해 green sheet를 제조하였다. 제조된 박판의 두께는 0.9mm였고, 평균 기공 크기는 3~5μm, 기공율은 55%였다. 소결체의 XRD 분석결과 2차성은 생성되지 않았으며, SEM 및 dot-Mapping image를 통해 Ni matrix 안에 W 입자가 미세하고 균일하게 분포되어 있어 고용강화 및 분산강화를 통해 Ni 음극의 기계적 특성을 향상시킬 것으로 기대된다.

A dual-porosity filmed agglomerate model for the porous cathode of the molten carbonate fuel has been investigated to predict the cell performance. A phenomenological treatment of molecular, kinetic and electrode parameters has been given. The major physical and chemical phenomena being modeled include mass transfer, ohmic losses and reaction kinetics at the electrodeelectrolyte interface. The model predicts steady-state cell performance given the above conditions that characterize the state of the electrode. Quasi-linearization and finite difference techniques are used to solve the coupled nonlinear differential equations. Also, the effective surface area of electrode pore was obtained by mercury porosimeter. The results of the investigation are presented in the form of plots of overpotential vs. current density with varied the electrode material, gas composition and mechanism. The predicted polarization curves are compared with the empirical data from 1 ㎠ cell. A fair correspondence is observed.

In the development of Molten Carbonate Fuel Cell, one of the serious problems is the dissolution of cathode material. Therefore, the development of the alternative cathode which is stable in molten carbonate is needed. In this research, the LiCoO2 was chosen as alternative cathode material. LiCoO2 powder was synthesized by high temperature calcination method and by citrate sol-gel method. And its structure and physical characteristics were analyzed by XRD, IR TGA and porosimeter. The conductivity and solubility of LiCoO2 electrode were also measured Homogeneous LiCoO2 powder was obtained by citrate sol-gel method at 445℃, however, obtained above 750℃ by high temperature calcination method. Homogeneous particle size distribution and fine powder were obtained by the citrate sol-gel method. LiCoO2 electrode showed higher electric conductivity (1.7 Ω^-1 ㎝^1) than NiO (0.1 Ω^-1 ㎝^-1) at 650℃. The solubilities of LiCoO2 electrode in electrolyte were varies 0.6 to 1.0 ppm during 200 hours. So, the solubilities of LiCoO2 were much lower than that of NiO.