Simulation study of anode gas and potential distribution of fuel cell based on lattice Boltzmann method

[Background] The lattice Boltzmann method (LBM) is suitable for studying the transport of microscopic particles in the complex porous anode electrochemical reaction process of solid oxide fuel cell (SOFC). [Purpose] This study aims at the microstructure change, gas and current density distribution in the process of SOFC anode electrochemical reaction in order to understand the cause of performance attenuation in the process of battery operation and provide reference for the optimization of anode structure. [Methods] First of all, the three-dimensional structure of SOFC anode samples after running 2 h and 20 h were obtained. Then, based on previous studies, the ion transport effects in the electrochemical reaction of anode was performed by using LBM to obtain the concentration distributions of hydrogen and water in anode, and the current density distribution of oxygen ions. [Results] After 20 h of SOFC operation, Ni particles migrate and aggregate, resulting in the increase of local Ni phase volume fraction and the decrease of effective three-phase interface length of anode. As the electrochemical reaction occurs at an effective three-phase boundary, the reduced length of the three-phase interface results in a reduction of SOFC performance. At the same time, as fuel cells run, hydrogen consumption decreased, oxygen ion consumption decreased, and water production decreased. [Conclusion] It is shown that LBM can be used to simulate an SOFC anode at microscale and evaluate the effect of structural parameters on the transport processes. (authors)