Preparation And Properties Of Electrolyte-Supported SOFCs With Ultra-Thin Honeycomb Structure

Solid oxide fuel cells（SOFCs）are all solid state power generation devices that can directly convert the chemical energy of fuel into electrical energy.They have the advantages of wide fuel adaptability,high energy conversion efficiency,modular assembly,zero pollution and so on.At present,the main problem of electrolyte supported SOFCs is that the thick electrolyte leads to high operating temperature.The preparation of honeycomb electrolyte can effectively solve this problem,thin areas are used to conduct O^2-,and thick areas play a supporting role to achieve the combination of electrochemical performance and mechanical stability.In this research,3D printing technology is mainly used to prepare ultra-thin honeycomb electrolyte supported SOFCs and study their performance.The main research results are as follows:First of all,based on the previous work,the effects of the types of ultraviolet absorbers,the amount of ultraviolet absorbers and the amount of photoinitiators added on the curing depth of the slurry were investigated,and the high solid phase（50 vol.%）,low viscosity(≤3.731 Pa·s at a shear rate of 10 s^-1)and low curing depth（60.5μm）,and explored the influence of exposure time on the curing depth of single-layer honeycomb structure,successfully prepared a honeycomb structure model that meets the requirements,laying a foundation for the subsequent electrolyte preparation of honeycomb electrolyte supported solid oxide fuel cells.Secondly,the above 8YSZ slurry was used to print test samples and conduct three-point bending test.Honeycomb structure samples with different parameters were also tested,mainly including changing the honeycomb pattern,honeycomb size,support edge width,adding chamfers and steps to the honeycomb to explore the honeycomb structure samples with the best mechanical properties.The results showed that the electrolyte with square honeycomb structure had the best mechanical properties,and the highest average failure load was 1.01 N.Finally,the above 8YSZ slurry was used to print electrolyte with honeycomb structure,and an electrolyte supported primary cell was prepared.Finally,its electrochemical performance was studied,and it was found that its power density could reach 215.4 m W/cm^-2,which was about twice as high as the flat primary cell 114 m W/cm^-2 prepared by the same method.To sum up,in this study,we successfully prepared a honeycomb structure model that meets the requirements by exploring the effects of the type of UV absorber,the amount of UV absorber added and the printing parameters on the curing depth of the slurry,and tested honeycomb structure samples with different parameters to find out that the mechanical properties of the electrolyte in the square honeycomb structure are the best,Finally,the printed electrolyte was assembled into a complete primary cell and its electrochemical performance was tested.The results show that the electrochemical performance of electrolyte-supported SOFCs with honeycomb structure is about one time higher than that of the flat cell prepared by the same method.