The typical solid oxide fuel cell (SOFC) consists of the dense electrolyte, porous cathode and anode. Among them, the electrolyte is an oxide ceramic material with all-solid-state structure, which is between the cathode and the anode. Electrolyte is one of the core components of SOFC, and it is the decisive factor for cell operating temperature and performance. At present, the research and application of high temperature electrolyte materials have been relatively mature. However, the high temperature operating conditions of the cell will bring a series of defects, such as the interface reaction between electrode and electrolyte, the difficulty of sealing and the shortening of the service life. Therefore, the development of SOFC electrolytes is gradually tending towards inter-temperature or lower. As the operating temperature decreases, the ohmic resistance (Ro) of the electrolyte is increased correspondingly, resulting in a decrease in the conductivity of the cell. On account of its, the performance improvement and optimization of electrolytes at intermediate temperatures have attracted much attention in recent years. In this paper, the latest research progress of several different oxygen ion conductor electrolytes is reviewed, and the main optimization strategies for electrolyte performance improvement under lower temperature operating conditions of SOFC are discussed. |