摘要
使用对称氧电极电池研究了La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)-Gd_(0.1)Ce_(0.9)O_(1.95)氧电极厚度与其电化学性能间的依赖关系。使用电化学阻抗谱测试方法在开路电压条件下测试了厚度为5μm~22μm的氧电极的电化学阻抗谱。同样制备并测试了不同厚度氧电极的燃料极支撑纽扣电池的电化学阻抗谱和循环伏安曲线。结果表明,随着氧电极厚度的变化,总极化阻抗Rp也随之变化。总极化阻抗来源于氧离子传输、氧表面交换和氧气的扩散过程;解析不同过程的阻抗可以发现,高频的氧离子传输过程与氧电极厚度的依赖性较弱;而氧表面交换过程和氧气的扩散过程与氧电极的依赖性强。通过优化氧电极的厚度能够优化氧电极的电化学性能;当氧电极为12μm时,其阻抗值达到最小值;750℃为0.034Ω·cm^(2。)基于此,在800℃、燃料气为3vol.%H_(2)O+97vol.%H2条件下,燃料极支撑纽扣电池(NiO-YSZ||YSZ||20GDC||LSCF-10GDC)的最大功率密度达到1098 mW·cm^(-2)。由于所获得电池氧电极的最优厚度仅为目前同类电池氧电极厚度的约一半,提出可商业化电池的“高性能薄膜氧电极”概念。
The relationship between the thickness and electrochemical performance of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)-Gd_(0.1)Ce_(0.9)O_(1.95)oxygen electrode was studied by using a symmetrical oxygen electrode cell.Electrochemical impedance spectroscopies of the oxygen electrode with thicknesses of 5–22μm were measured at various open-circuit voltages.The electrochemical impedance spectra and cyclic voltammetry curves of the fuel supported button cells with oxygen electrodes of different thicknesses were also tested.It is found that the total polarization impedance(Rp)changes with thickness change of the oxygen electrode.The total polarization impedance is derived from oxygen ion transfer,oxygen surface exchange and oxygen diffusion.By analyzing the impedances of different processes,it can be found that the high frequency oxygen ion transport process has a weak dependence on the oxygen electrode thickness.The surface exchange and diffusion of oxygen are strongly dependent on thickness of the oxygen electrode.The electrochemical performance of the oxygen electrode can be improved by optimizing the thickness.The lowest value of resistance is reached at 12μm,which is 0.034Ω·cm2 at 750℃.Accordingly,the maximum power density of the fuel electrode supported button cell(NiO-YSZ||YSZ||20GDC||LSCF-10GDC)is 1098 mW·cm^(−2),with 3 vol.%H2O+97 vol.%H2 as fuel and static air as oxidant at 800℃.Because the optimal thickness of the oxygen electrode obtained is only about half of the thickness of the currently similar oxygen electrode,the concept of“thin film oxygen electrode”was proposed for possible commercialization.
作者
王章苇
罗凌虹
程亮
王乐莹
徐序
余剑锋
刘邵帅
张双双
WANG Zhangwei;LUO Linghong;CHENG Liang;WANG Leying;XU Xu;YU Jianfeng;LIU Shaoshuai;ZHANG Shuangshuang(School of Materials Science and Engineering,Jingdezhen Ceramic University,Jingdezhen 333403,Jiangxi,China;National Engineering Research Center for Domestic&Building Ceramics,Jingdezhen Ceramic University,Jingdezhen 333001,Jiangxi,China;Jiangxi Provincial Key Laboratory of Fuel Cell Materials and Devices,Jingdezhen 333001,Jiangxi,China)
出处
《陶瓷学报》
CAS
北大核心
2023年第4期751-760,共10页
Journal of Ceramics
基金
江西省自然科学基金重点项目(20224ACB204010)
江西省教育厅科技落地计划(KJLD13072)
江西省教育厅科技项目(GJJ2201009,GJJ2201010)。
