Structure Analysis And Interconnect Design For MOLB-type Solid Oxide Fuel Cell

Solid Oxide Fuel Cell(SOFC)is considered to be a promising energy conversion device.Due to its high efficiency,cleanness,quiet and other significant advantages to become the focus of energy structure improvement and development in the 21 st century.MOLB-type(Mono-block-layer built type)SOFC as a kind of SOFC,named as its corrugated appearance,the corrugated-shaped PEN(Positive electrode-electrolyte-negative electrode)not only improves the reaction area,but also forms the airway of PEN itself compared with planar SOFC.With the development of MOLB-type SOFC,it’s performance is getting better and better,the output current is increasing,cause the influence of its ohmic polarization is becoming more and more obvious.Therefore,this paper starts from the analysis of MOLB-type SOFC structure,discusses the influence law of key geometric structure parameters on its ohmic polarization and performance,provides the theoretical reference for further improvement of MOLB-type SOFC performance.The main research contents are as follows:1.With the increase of flow channel height,the output power of MOLB-type SOFC is increasing,while the volume power density is decreasing.Compared with planar SOFC,both output power and volume power density of MOLB-type SOFC have obvious advantages,and the advantage increases with the increase of flow channel height.2.The output power and volume power density of MOLB-type SOFC decrease with the increase of anode thickness,so the anode thickness should not be too thick and 500?m is suitable.For the cathode thickness,there is an optimal cathode thickness to make volume power density reach the maximum,while the output power of the cell is basically unchanged when the thickness of the cathode is greater than 250?m,so the suitable thickness of the cathode is 250?m.3.In view of the current flow path is too long and the ohmic polarization is too large caused by the structure of MOLB-type SOFC original design,three new design schemes(scheme a,scheme b and scheme c)are proposed in this paper.Compared with the original design,three new designs shorten the current transmission path,reduce the ohmic polarization by nearly 50%,and the cell performance improved significantly.When the porosity and conductivity are different,the advantages of the three new design schemes compared with the original design remain basically unchanged.The performance of threenew design schemes is not different,but the performance of scheme a is slightly better than that of the other two schemes.4.In this paper,the mechanical model is established for the original design structure and three new design structures.It is found that the maximum Mises stress of scheme b and scheme c is basically the same as the original design structure.However,the maximum Mises stress of scheme a is only 13% of the original design.Therefore,compared with the original design,scheme a not only has outstanding advantage in electrochemical performance,but also its mechanical properties have been greatly improved.