Investigation Study Of Anode Microstructure On The Performance Of Planer IT-SOFC Single Cell

Solid oxide fuel cell (SOFC) is a kind of highly effective power system, which has attracted much attention because of its remarkable advantages such as flexibility of fuels, whole solid structure and no noble metal catalysts. Nowadays, one of the main trends is to reduce the operating temperature of SOFC from 1000?C to intermediate temperature below 800?C, which is beneficial for the commercialization, and civilian of SOFC. The thickness of the electrolyte has direct relationship with anode cation conduction, the ionic conductivity will be much higher when the thickness of the electrolyte is thinner. It is beneficial for reducing the operation temperature reduction of SOFC. One of the effective methods to reduce the operation temperature is preparing the electrolyte thin film with high performance, and the electrolyte thin film adheres to the porous anode. So the anode supported structure is mainly discussed in the paper.In this paper, YSZ electrolyte layer and anode layer were prepared by aqueous tape casting method. The main purpose of adding pore formers was to increase the porosity and to optimize the microstructure of anode. The effect of the content of single pore former on the porosity and microstructure of anode, the electrochemical properties of single cell have been investigated using polymethl metharylate (PMMA) and graphite as the single pore former. The results showed that the optimal pore formers (PMMA and graphite) content is 20wt.%, which made the optimum electrochemical properties. The OCV of the single cell was nearly 1.1V and the maximum power density achieved 0.81W/cm2 and 0.91 W/cm2 at 800?C with 3%H2O+H2/O2 as the operating gases.The effect of different ratio of PMMA and graphite on anode and the electrochemical performance of cell were investigated. The results showed that the best proportion of the pore formers is PMMA: graphite=1:1. The strength of the anode prepared by composite pore formers was much higher than prepared by single pore formers. There was no significant difference between the porosities of anodes prepared using single pore formers and complex pore former with the same pore former content. When the proportion of the pore formers was 1:1, the connected pores were distributed homogeneously in the anode. The area-specific resistance (ASR) of the obtained single cell was found to be the smallest as 0.54 ?cm2, and the maximum power density of the single cell achieved 1.06 W/cm2 at 800?C with 3%H2O+H2/O2 as the operating gases. The sintering shrinkage of the anode and electrolyte were matched well with each other.The sintering shrinkage of anode and electrolyte matched well with each other by adding optimum amount ofα-Al₂O₃ to the anode. The influence of the amount ofα-Al₂O₃ on sintering shrinkage and microstructure of anode and the performance of single cell with the optimalα-Al₂O₃ content was investigated. When the optimum amount ofα-Al₂O₃ was 3wt.%, the anode and electrolyte matched well with each other, and the pores were distributed well in the anode, the anode has good thermal shock resistance. The electrochemical performance of the single cell was not affected by addingα-Al₂O₃, and the maximum power density achieved 1.02 W/cm2, which was useful for preparing large area and flat planar anode supported SOFC.