Reconstruction of solid oxide fuel cell electrode microstructure and analysis of its effective conductivity

作     者：Keqing Zheng Meng Ni 

作者机构：Building Energy Research Group Department of Building and Real Estate The Hong Kong Polytechnic University Environmental Energy Research Group Research Institute for Sustainable Urban Development (RISUD) The Hong Kong Polytechnic University 

出 版 物：《Science Bulletin》 (科学通报（英文版）)

年 卷 期：2016年第61卷第1期

页      面：78-85页

核心收录：

学科分类：0808[工学-电气工程] 080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080401[工学-精密仪器及机械] 0804[工学-仪器科学与技术] 0803[工学-光学工程] 

基　　金：supported by a grant from Research Grant Council University Grants Committee Hong Kong SAR(Poly U 152127/14E) 

主　　题：Fuel cell Electrode Conductivity Modeling Random particle packing 

摘      要：The effective conductivity （aeff） of solid oxide fuel cell （SOFC） electrode is an important parameter for predicting the ohmic loss in SOFC. This paper investigates the effective conductivity of SOFC electrodes recon- structed numerically by packing spherical particles in a computational domain, followed by a dilation process to simulate the sintering procedure. The effects of various parameters on the effective conductivity of the electrodes are investigated, including material composition, porosity, particle size and contact angle. Results show that the effective conductivity ratio （aeff/ao） of the computed con- ducting phase is mainly affected by its total volume frac- tion （VF） in electrode （including the porosity）. The effective conductivity can be improved by increasing the VF, electrode particle size or the contact angle between electrode particles. Based on the numerical results, the conventional percolation model for the calculation of O＇eft is improved by adjusting the Bruggeman factor from 1.5 to 2.7. The results are useful for understanding the microstructure properties of SOFC composite electrode and for subsequent electrode optimization.