Process for fabrication of a fully dense electrolyte layer embedded in membrane electrolyte assembly of solid oxide fuel cell

A manufacturing process for producing a planar solid oxide fuel cell (SOFC-MEA) having a fully dense electrolyte layer, the process uses tape casting process to produce planar SOFC-MEA anode and electrolyte green tapes, and then cuts and laminates the electrolyte green tape and anode green tape to produce SOFC half cell, under specially designed and controlled sintering condition, the process can produce planar solid oxide fuel cell that has a fully dense and airtight electrolyte layer (8YSZ/GDC/LSGM), comprising the following steps:

• a. Using tape casting process to produce planar SOFC-MEA anode and electrolyte green tapes;
• b. Building of the electrolyte green tape thin layer onto the electrode green tape and through lamination with proper pressure, temperature and system vacuum, produce SOFC green half cell;
• c. Using lamination technology the green tapes of electrolyte and electrode are tightly combined;
• the anode/electrolyte composite green tape is subject to high-temperature sintering to produce ceramic half cell, it is about 1500° C. for 5 hours;
• SEM is used to inspect the result to assure the full densification of electrolyte layer, if a fully dense structure is achieved, go to Step d, if open pores still exist, use spin coating or sputtering coating processes for improvement or adjust sintering condition until fully dense electrolyte layer is achieved, then the half cell is named HC-fd;
• d. Using screen printing to build a layer of cathode material onto the electrolyte layer of HC-fd., and conducting sintering at about 1200° C. for about 3 hours to complete the manufacturing of unit cell, sintering temperature rising/dropping rate is, but not limited to 3° C./min;
• e. Conducting testing on the produced unit cell for electrical operation and power density measurement to verify its electric performance.