摘要
固体氧化物燃料电池(SOFC)和固体氧化物电解池(SOEC)电堆的电化学分析和诊断是国际上的研究难点。明确多片电堆的本征电化学反应机理和性能规律,是SOFC/SOEC技术实用化的关键。本研究采用弛豫时间分布法(DRT)耦合阻抗谱差异分析法(ADIS)对电堆在燃料电池模式和电解池模式下的复杂电化学行为进行了研究,通过弛豫时间解析出各个过程对应的特征峰,区分出不同的物理化学过程。研究表明,电堆在SOFC模式运行时,其氢电极含水量应大于20%,而SOEC模式运行时,含水量应小于80%,以最小化电池的气体扩散阻抗。本方法可应用于SOFC/SOEC电堆的分析诊断,简化电堆测量分析的复杂性,有助于电堆衰减机理和原因的实时诊断,并对电堆性能提高给出理论依据和指导建议。
Electrochemical analysis and diagnosis of the SOC stacks, including Solid Oxide Fuel Cells （SOFC） and Solid Oxide Electrolysis Cells （SOEC）, are one of the research challenges in world. In order to optimize performance and realize practical SOC application, it is crucial to investigate kinetic mechanisms and reaction principle of the mul- tiple-cells stack. In this paper, the relaxation time distribution method （DRT） combined with the analysis of difference in impedance spectra method （ADIS） were employed to research the complex electrochemical behavior of SOC stacks under different operation modes. The DRT characteristic peaks were identified through the analysis and as-segment of the relaxation time. The changes in the DRT peaks were correlated with the different electrochemical process. The research achievements indicate that the water content should be more than 20% when operated at SOFC mode, while less than 80% when operated at SOEC mode to minimize the gas diffusion resistance. The research achievements can provide theoretical data and establish technical foundation for the further study and application of this novel method, which can reduce the SOC complexity of EIS analysis, apply for the degradation identification and online diagnosis of stacks, and help to improve the SOC performance.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2016年第12期1279-1288,共10页
Journal of Inorganic Materials
基金
国家自然科学基金(21273128,51202123)
教育部长江学者与创新团队计划(IRT13026)~~
关键词
电化学阻抗谱
弛豫时间分布法
固体氧化物电解池
阻抗谱差异分析法
衰减机理
electrochemical impedance spectroscopy
distribution of relaxation times
solid oxide electrolysis cell
analysis of the difference in impedance spectra
degradation mechanisms
