| Solid Oxide Fuel Cell (SOFC) was considered as one of the most promising energy sources in the 21st century, so many countries increased financing to research the commercial of SOFC. The efficiency of SOFC was influenced greatly by cell's voltage which related to the density of the electrolyte film, so, many research institutions focu on how to find the effective technology to fabricate dense electrolyte film.In this paper, we successfully developed a screen printing method to fabricate YSZ (yttria-stabilized zirconia) film which was about 31μm thick on NiO-YSZ substrate. The Ni/YSZ/La0.7Sr0.3MnO3 cell performance was investigated as well: the open circuit voltage was 1.07 V and the maximum power density was 1.3 W/cm2 at 850℃.In order to research the screen-printing technology in detail, we investigated the process parameters, including starting YSZ powder, printing times, sintering temperature of YSZ films, printing ink composition, and so on. Thereinto, the starting YSZ powder exerts a crucial influence on the microstructure of the screen-printed YSZ electrolyte films, the film prepared from the YSZ powder without being ball-milled was very porous while the film made from the YSZ powder having been ball milled was dense and gas-tight; At least 7-layer printing was necessary to obtain dense YSZ film and steady cell voltage, and the impedance of the electrolyte did not increased after the film was printed about ten layers; The film fabricated with ball-milled 13 h YSZ powder which was sintered at 1300℃for 4 h was dense, but there was still a little spacing among crystal grains. For the sake of obtaining dense YSZ film and improving the property of SOFC, the film should be sintered at 1400℃.
|
PDF Full Text Request