Solid oxide fuel cells (SOFCs) have received considerable interest nowadays, because they promise greater electrical efficiency than that obtained by a conventional heat engine or other types of low temperature fuel cells. Validated mathematical models provide a very powerful tool for the development of improved SOFC designs and operating conditions. From some literature and numerical simulation results, it could be found that the concentration gradient of fuel and oxidant gas is great on the plane which is normal to the SOFC tri-layer, especially in the porous electrode. But the structures in the previous literature and inventions are always focusing on the disturbance of flow on the plane which is parallel to the SOFC tri-layer. In order to lower the concentration polarization of SOFC, We have invented a novel SOFC with bi-layerer interconnector which can disturb the fuel and air gas on the plane which is normal to the SOFC tri-layer and enhance the mass transfer effectively. In this paper, the primary objective is to compare the concentration overpotentials under the different interconnects modes. A 2D half-cell model has been developed to study on concentration overpotentials of fuel side of the SOFC stack with conventional interconnects and novel bi-layer interconnects. The numerical simulation results show that the novel interconnect can disturb the fuel and air gas on the plane which is normal to the SOFC tri-layer and reduce the concentration overpotential of SOFC. It can enhance the mass transfer in porous electrode and improve the performance of SOFC.