多孔Fe24Cr金属支撑体厚度对SOFC性能的影响  

Effect of Thickness of Porous Fe24Cr Metal Support on SOFC Performance

作　　者：王丕 宋琛 董东东 曾德长[1] 刘太楷 文魁 毛杰 刘敏 WANG Pi;SONG Chen;DONG Dongdong;ZENG Dengchang;LIU Taikai;WEN Kui;MAO Jie;LIU Min(School of Materials Science and Engineering,South China University of Technology,Guangzhou 510641,China;National Engineering Laboratory for Modern Materials Surface Engineering Technology,Key Lab of Guangdong for Modern Surface Engineering Technology,Institute of New Materials,Guangdong Academy of Sciences,Guangzhou 510650,China)

机构地区：[1]华南理工大学材料科学与工程学院,广州510641 [2]广东省科学院新材料研究所,现代材料表面工程技术国家工程实验室,广东省现代表面工程技术重点实验室,广州510650

出　　处：《材料导报》2025年第1期115-121,共7页Materials Reports

基　　金：国家重点研发计划(2023YFE0108000);国家自然科学基金(52201069);中国科协青年人才托举项目(2022QNRC001);广东省科学院项目(2022GDASZH-2022010201;2022GDASZH-2022010203-003;2022GDASZH-2022030501-06);广东省科学院新材料研究所专项资金项目(2023GINMZX-202301020104)。

摘　　要：金属支撑型固体氧化物燃料电池(MS-SOFC)因成本低、力学性能好、可快速启停等优点,有望应用于无人机、便携式、移动式电源领域。为提高MS-SOFC性能与寿命,金属支撑体不仅需要与电解质热膨胀系数匹配以减少应力,还需要高透气性以提高燃料气体的扩散及反应速度。因此,本工作制备了厚度分别为1 mm、0.8 mm、0.5 mm的三种不同Fe24Cr支撑体,对比研究其与传统430支撑体的热膨胀系数,系统探究了厚度对支撑体透气性和SOFC电化学性能的影响。研究结果表明,Fe24Cr支撑体的热膨胀系数为12.74×10^(-6)K^(-1),比传统430支撑体更加适配氧化锆基电解质。0.5 mm厚Fe24Cr支撑体可明显缩短气体传输路径,相较1 mm厚Fe24Cr支撑体透气量提高约5倍,输出性能增长15%以上;800℃下电池的极化阻抗和欧姆阻抗分别降至0.203Ω·cm^(2)和0.118Ω·cm^(2),峰值功率密度达1.215 W/cm^(2)。采用弛豫时间分布(DRT)方法分析的结果表明,支撑体厚度的减薄对SOFC的欧姆阻抗和H_(2)扩散至三相反应界面的速率有较大贡献,可以和电池的电化学性能规律吻合良好。The metal-supportedsolid oxide fuel cel(MS-SOFC)is expected to be used in unmanned aerial vehicles,portable power and mobile powers due to its advantages such as low cost,good mechanical properties and fast start-stop capability.In order to improve the performance and lifetime of MS-SOFC,the metal support not only needs to match the thermal expansion coefficient of electrolyte to reduce stress,but also needs high permeability to improve the diffusion and reaction rate of fuel gas.In this work,three kinds of Fe24Cr supports with different thickness of 1 mm,0.8 mm and 0.5 mm were prepared,and their coefficient of thermal expansion were compared with the traditional 430 support.Mean-while,the effects of the thickness on the air permeability and electrochemical performance of the support were investigated.The results showed that the coefficient of thermal expansion of Fe24Cr support is 12.74x10^(-6)K^(-1),which is more suitable for zirconia-based electrolyte than the tradi-tional 430 support.Comparing with the 1 mm thick support,the 0.5 mm thick Fe24Cr support can significantly shorten the gas transmission path,increase the gas permeability by about 5 times and increase the output performance by more than 15%.At 800℃the polarization impedance and ohmic impedance of the cell decrease to 0.203Ω·cm^(2) and 0.118Ω·cm^(2) respectively,and the peak power density reaches 1.215 W/cm^(2).The distribution of relaxation times(DRT)analysis showed that the reduction of the support thickness contributes greatly to the ohmic impedance of SOFC and the rate of H_(2) diffusion to the three-phase reaction interface,which can be matched well with the electrochemical perfomance results of the cell.

关 键 词：金属支撑型SOFC 支撑体厚度 热膨胀系数 透气性 电化学性能 

分 类 号：TK91[动力工程及工程热物理]