电化学阻抗技术在固体氧化物燃料电池中的应用

Application of Electrochemical Impedance Spectroscopy in Solid Oxide Fuel Cells

摘要:

固体氧化物燃料电池（SOFC）在高温条件下长时间运行会发生性能衰减，表现为电池电压下降，阻抗增加，故通过研究电池阻抗变化规律可以分析电池性能衰减原因。作为一种无损在线检测技术—电化学阻抗谱技术(EIS)可分析各衰减因素对单电池阻抗增长的影响规律，如材料结构的退化、毒化等衰减因素导致的电池片欧姆阻抗或极化阻抗的增长。结合弛豫时间分布法（DRT）和等效电路（ECM）拟合等方式，可进一步确定导致电池性能衰减的部件和各衰减因素对电池总阻抗增加的占比率。详细论述了电化学阻抗分析技术在阳极支撑Ni-8YSZ/8YSZ/GDC/LSCF电池片衰减机制中的应用，同时针对其具体失效原因给出有效的解决方案，对制备高性能、低衰减单电池具有重要意义。

Abstract:

Solid oxide fuel cell （SOFC） will experience performance degradation when it operates at high temperature for a long time， which is manifested as a decrease in cell voltage and an increase in impedance. Therefore， the cause of cell performance degradation can be analyzed by studying the change law of cell impedance. As a nondestructive on-line detection technology， electrochemical impedance spectroscopy （EIS） can analyze the influence of various attenuation factors on the growth of cell impedance， such as the increase of the ohmic or polarization resistance caused by degradation or poisoning of the material structure. Combined with the relaxation time distribution method （DRT） and equivalent circuit （ECM） fitting， it is possible to further determine the components that cause cell performance attenuation and the proportion of each attenuation factor to the increase in the total cell impedance. This review discusses in detail the application of electrochemical impedance analysis technology in the attenuation mechanism of anode-supported Ni-8YSZ/8YSZ/GDC/LSCF cells， and provides an effective solution for the specific failure reasons， which is of great significance for the preparation of high-performance， low-attenuation single cells.