Effect of Anodic Concentration Overvoltage on Power Generation Characteristics of Solid Oxide Fuel Cells
Effect of Anodic Concentration Overvoltage on Power Generation Characteristics of Solid Oxide Fuel Cells
复制标题
阳极浓集过电压对固体氧化物燃料电池发电特性的影响
DOI：
10.1149/1.1837274
复制
发表时间：
1996
影响因子：
3.9
通讯作者：
H. Arai
中科院分区：
文献类型：
--
作者：
K. Eguchi;Y. Kunisa;K. Adachi;H. Arai
测量了具有 8 摩尔% 氧化钇稳定氧化锆 (YSZ) 电解质和 Ni-YSZ 阳极的 H{sub 2} 燃料固体氧化物燃料电池的电流-电压 (I-V) 和阳极极化特性。对于富含H{sub 2}的H{sub 2}-H{sub 2}O体系，I-V曲线的特点是开路电压高，并且在小电流密度区域有明显的凹形弯曲。对于极度稀薄的燃料条件，曲线从电压直线下降开始，然后由于限制电流而导致电压急剧下降。在根据燃料系统中计算的平衡 P{sub O{sub 2}} 确定 I-V 曲线的形状时，提出了浓度过电压的显着贡献。实验获得的阳极极化曲线可以与基于 Ni-YSZ 阳极层浓度差的计算曲线拟合。 Ni-YSZ 金属陶瓷影响阳极极化的有效扩散系数 D{sub eff} 估计为 10{sup {minus}2} 至 10{sup {minus}1} cm{sup 2}/s。电极极化电导率在 P{sub O{sub 2}} = ca 时最大。 10{sup {minus}8} Pa，并随着 P{sub O{sub 2}} 的增加或减少而减少。这种行为可以通过考虑浓度过电压来解释，该浓度过电压基于 log P{sub O{sub 2}}more » 和 H{sub 2} 分数浓度之间的关系。« less
Current-voltage (I-V) and anodic polarization characteristics were measured for the H{sub 2}-fueled solid oxide fuel cell with an 8 mole percent yttria-stabilized zirconia (YSZ) electrolyte and Ni-YSZ anode. For a H{sub 2}-rich H{sub 2}-H{sub 2}O system, the I-V curve was characterized by a high open-circuit voltage and significant concave bending in the small current density region. For an extremely dilute fuel condition, the curve started from a straight decrease of the voltage followed by a sharp voltage drop due to limiting current. Significant contribution of concentration overvoltage was suggested in determining the shape of the I-V curve from the calculated equilibrium P{sub O{sub 2}} in the fuel systems. The experimentally obtained anodic polarization curve could be fitted to the calculated curve based on the concentration difference across the Ni-YSZ anode layer. The effective diffusion coefficient, D{sub eff}, of the Ni-YSZ cermet which affects the anodic polarization, is estimated to be 10{sup {minus}2} to 10{sup {minus}1} cm{sup 2}/s. The electrode polarization conductivity, was maximum at P{sub O{sub 2}} = ca. 10{sup {minus}8} Pa, and decreased with increasing or decreasing P{sub O{sub 2}}. This behavior could be explained by considering the concentration over-voltage based on the relation between log P{sub O{sub 2}}more » and the fractional concentration of H{sub 2}.« less